Note: Descriptions are shown in the official language in which they were submitted.
WO 2021/198656
PCT/GB2021/050755
AEROSOL GENERATING COMPONENT COMPRISING A CAPILLARY
STRUCTURE
Field
The present invention relates to a delivery system, in particular to a non-
combustible
aerosol delivery system and to components of said aerosol delivery system. The
present
invention further relates to methods of generating and delivering an aerosol
using the non-
combustible aerosol delivery system and components disclosed herein.
Background
Non-combustible aerosol delivery systems which generate an aerosol for
inhalation by a
user are known in the art. Such systems typically comprise an aerosol
generator which is
capable of converting an aerosolisable material into an aerosol. In some
instances, the aerosol
generated is a condensation aerosol whereby an aerosolisable material is first
vaporized and
then allowed to condense into an aerosol. In other instances, the aerosol
generated is an
aerosol which results from the atomization of the aerosolisable material. Such
atomization may
be brought about mechanically, e.g. by subjecting the aerosolisable material
to vibrations so as
to form small particles of material that are entrained in airflow.
Alternatively, such atomization
may be brought about electrostatically, or in other ways, such as by using
pressure etc.
Since such aerosol delivery systems are intended to generate an aerosol which
is to be
inhaled by a user, consideration should be given to the characteristics of the
aerosol produced.
These characteristics can include the size of the particles of the aerosol,
the total amount of the
aerosol produced, etc.
Where the aerosol delivery system is used to simulate a smoking experience,
e.g. as an
e-cigarette or similar product, control of these various characteristics is
especially important
since the user may expect a specific sensorial experience to result from the
use of the system.
It would be desirable to provide aerosol delivery systems which have improved
control of these
characteristics.
Summary
In one aspect there is provided an aerosol generating component comprising a
capillary
structure, wherein the capillarity of a first portion of the capillary
structure varies relative to the
capillarity of a second portion of the capillary structure.
The first portion and the second portion may have different rates of
vaporisation of
aerosolisable material.
The capillarity may be greater in those areas having a greater rate of
vaporisation.
1
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
The different rates of vaporisation may correspond with portions having
greater and
lesser propensity for the flow of electrical current.
The portions having greater and lesser propensity for the flow of electrical
current may
have different densities.
The portions having a greater rate of vaporization may have a density of up to
300% of
the density of the portions having a lesser rate of vaporization. The portions
having a greater
rate of vaporization may have a density of up to 250% of the density of the
portions having a
lesser rate of vaporization. The portions having a greater rate of
vaporization may have a
density of up to 200% of the density of the portions having a lesser rate of
vaporization.
The portions having a greater rate of vaporisation may be disposed, relative
to the
longitudinal axis of the aerosol generating component, inwardly of the
portions having a lesser
rate of vaporisation.
The portions having a greater rate of vaporisation may be disposed, relative
to the
longitudinal axis of the aerosol generating component, outwardly of the
portions having a lesser
rate of vaporisation.
The component for transferring aerosolisable material to the aerosol
generating
component comprises a feed aperture.
The at least one feed aperture may be located in greater proximity to the
portions of the
aerosol generating component having a greater rate of vaporisation than the
portions of the
aerosol generating component having lesser rate of vaporisation.
The at least one feed aperture may be located at the boundary of the portions
having
greater and lesser rates of vaporisation.
The profile of the boundary between the portions having greater and lesser
rates of
vaporisation may be non-linear.
The portions having a lesser propensity for the flow of electrical current may
be disposed
at the periphery of the aerosol generating component.
The aerosol generating component may be formed from a woven or weave
structure,
mesh structure, fabric structure, open-pored fiber structure, open-pored
sintered structure,
open-pored foam or open-pored deposition structure.
The first portion may have a different thickness to the second portion.
The aerosol generating component may be substantially rectangular.
The aerosol generating component may comprise one or more apertures, which may
be
one or more slots.
2
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
The one or more apertures/slots may originate from the periphery of the
aerosol
generating component.
In a further aspect, there is provided an article comprising an aerosol
generating as
defined herein, the aerosol generating component being suspended within an
aerosol
generating chamber.
The aerosol generating chamber may comprise at least one air inlet and at
least one air
outlet.
The air inlet and air outlet may be aligned substantially parallel to the
plane of the
aerosol generating component.
The air inlet and air outlet may be are aligned substantially transverse to
the plane of the
aerosol generating component.
The article may comprise a store for aerosolisable material.
The store may extend annularly around the aerosol generating chamber.
An external wall of the aerosol generating chamber may form an internal wall
of the
store.
The store may comprise aerosolisable material.
A further aspect of the present invention provides a non-combustible aerosol
provision
system comprising the article as defined herein and a device comprising a
power source and a
control unit.
A further aspect of the present invention provides a method of forming an
aerosol
generating component, the method comprising the steps of: providing an aerosol
generating
component having a capillary structure, and compressing the aerosol generating
component in
one or more portions to increase the density in those compressed portions.
The aerosol generating component formed by the method may be characterized in
accordance with the various features for the aerosol generating component
described herein.
Brief Description of the Drawings
Various embodiments will now be described in detail by way of example only
with
reference to the accompanying drawings in which:
Figure 1 provides a schematic overview of certain components of a non-
combustible
aerosol delivery system as described herein;
Figure 2 provides an exploded view of an atomizer and associated components
which
according to various aspects of the present disclosure;
Figure 3 provides a view of certain components of Figure 2 in a stage of
assembly;
3
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Figure 4 provides a view of certain components of Figure 2 in a further stage
of
assembly relative to that shown in Figure 3;
Figure 5 provides a view of certain components of Figure 2 in a further stage
of
assembly relative to that shown in Figure 4;
Figure 6 provides a view of certain components of Figure 2 in a further stage
of
assembly relative to that shown in Figure 5;
Figure 7 provides a schematic cross section parallel to the longitudinal axis
though the
atomizer depicted in Figures 2 to 6;
Figure 8 provides a perspective view of an exemplary aerosol generating
component
according to the present disclosure;
Figure 8a provides a schematic illustration of aerosolisable material being
fed to the
periphery of an aerosol generating component in a plane parallel to the
aerosol generating
component;
Figure 8b provides a schematic illustration of aerosolisable material being
fed to the
periphery of an aerosol generating component in a plane perpendicular to the
aerosol
generating component;
Figure 8c provides an exploded view of capillary frame elements and aerosol
generating
component according to the present disclosure;
Figure 9a provides a perspective view of a schematic illustration of an
aerosol
generating component held within a capillary frame according to the present
disclosure;
Figure 9b provides a schematic cross section perpendicular to the longitudinal
axis of an
aerosol generating chamber of an aerosol generating component held within a
capillary frame
according to the present disclosure;
Figure 9c provides a schematic cross-section of a capillary frame having an
aerofoil
edge profile;
Figures 9d to 9f provide images of exemplary aerosol generating components
according
to the present disclosure;
Figures 10a and 10b provide schematic cross sectional views parallel to the
longitudinal
axis of a reservoir of an article according to the present disclosure;
Figure 10c provides a schematic cross sectional plan perpendicular to the
longitudinal
axis of a reservoir of an article according to the present disclosure;
Figure 11a provides a perspective image of an exemplary aerosol generating
component
and capillary gap according to the present disclosure;
4
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Figure llb provides a perspective image of another exemplary aerosol
generating
component according to the present disclosure;
Figure 12 provides a schematic plan view of an exemplary aerosol generating
component projecting into a capillary gap according to the present disclosure;
Figure 13 provides a schematic illustration of an aerosol generating chamber
comprising
an aerosol generating component;
Figure 13a provides a schematic illustration of an aerosol generating chamber
comprising an aerosol generating component suspended therein;
Figure 13b provides a schematic plan view of an aerosol generating component
wherein
respective areas of different vaporisation efficiency are depicted;
Figures 14a and 14b provide schematic illustrations of an aerosol generating
chamber
comprising an aerosol generating component, with the aerosol generating
chamber having one
or more air inlets in accordance with the present disclosure;
Figure 15a provides an end view of an air inlet configuration of an aerosol
generating
chamber according to the present disclosure;
Figures 15b and 15c show air inlet configurations in accordance with the
aerosol
generating chamber shown in Figures 14a and 14b respectively;
Figure 15d provides a graph showing the effect of varying the air inlet
configuration on
the particle size of an aerosol generated by an aerosol generating component
as described
herein;
Figures 16a to 16f show various air inlet configurations according to the
present
disclosure.
Figure 17a provides a cross-sectional view parallel to the longitudinal axis
of an article
according to the present disclosure;
Figure 17b provides a cross-sectional view of the article of Figure 17a, the
cross-section
being taken in Figure 17b perpendicular to the longitudinal axis of the
article;
Figures 18a and 18b provide a graphic illustration of different temperature
profiles along
a flow path between an air inlet and an air outlet of an aerosol generating
chamber as described
herein;
Figure 18c provides a schematic image of an aerosol generating component
according
to the present disclosure.
Detailed Description
5
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Aspects and features of certain examples and embodiments are discussed /
described
herein. Some aspects and features of certain examples and embodiments may be
implemented
conventionally and these are not discussed / described in detail in the
interests of brevity. It will
thus be appreciated that aspects and features of apparatus and methods
discussed herein
which are not described in detail may be implemented in accordance with any
conventional
techniques for implementing such aspects and features.
As described above, the present disclosure relates to (but is not limited to)
non-
combustible aerosol provision systems and devices that release compounds from
an aerosol-
generating material (or aerosolisable material) without combusting the aerosol-
generating
material. Examples of such systems include electronic cigarettes, tobacco
heating systems,
and hybrid systems (which generate aerosol using a combination of aerosol-
generating
materials). In some examples, the non-combustible aerosol provision system is
an electronic
cigarette, also known as a vaping device or electronic nicotine delivery
system (END), although
it is noted that the presence of nicotine in the aerosol-generating material
is not a requirement.
In some examples, the non-combustible aerosol provision system is an aerosol-
generating
material heating system, also known as a heat-not-burn system. An example of
such a system
is a tobacco heating system. In some examples, the non-combustible aerosol
provision system
is a hybrid system to generate aerosol using a combination of aerosol-
generating materials, one
or a plurality of which may be heated. Each of the aerosol-generating
materials may be, for
example, in the form of a solid, liquid or gel and may or may not contain
nicotine. In some
examples, the hybrid system comprises a liquid or gel aerosol-generating
material and a solid
aerosol-generating material. The solid aerosol-generating material may
comprise, for example,
tobacco or a non-tobacco product.
Throughout the following description the terms "e-cigarette" and "electronic
cigarette"
may sometimes be used; however, it will be appreciated these terms may be used
interchangeably with non-combustible aerosol (vapor) provision system or
device as explained
above.
In some examples, the present disclosure relates to consumables for holding
aerosol-
generating material, and which are configured to be used with non-combustible
aerosol
provision devices. These consumables are sometimes referred to as articles
throughout the
present disclosure.
The non-combustible aerosol provision system typically comprises a device part
and a
consumable/article part. The device part typically comprises a power source
and a controller.
The power source is typically an electric power source.
6
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
In some examples, the non-combustible aerosol provision system may comprise an
area
for receiving the consumable, an aerosol generator, an aerosol generation area
(which may be
within the consumable/article), a housing, a mouthpiece, a filter and/or an
aerosol-modifying
agent.
In some examples, the consumable/article for use with the non-combustible
aerosol
provision device may comprise aerosol-generating material, an aerosol-
generating material
storage area, an aerosol-generating material transfer component, an aerosol
generator, an
aerosol generation area, a housing, a wrapper, a filter, a mouthpiece, and/or
an aerosol-
modifying agent.
The systems described herein typically generate an inhalable aerosol by
vaporisation of
an aerosol generating material. The aerosol generating material may comprise
one or more
active constituents, one or more flavours, one or more aerosol-former
materials, and/or one or
more other functional materials.
Aerosol-generating material may, for example, be in the form of a solid,
liquid or gel
which may or may not contain an active substance and/or flavourants. In some
examples, the
aerosol-generating material may comprise an "amorphous solid", which may
alternatively be
referred to as a "monolithic solid" (i.e. non-fibrous). In some examples, the
amorphous solid
may be a dried gel. The amorphous solid is a solid material that may retain
some fluid, such as
liquid, within it. In some examples, the aerosol-generating material may for
example comprise
from about 50wV/0, 60wV/0 or 70wr/o of amorphous solid, to about 90wr/o,
95wtcY0 or 100wt% of
amorphous solid.
The term "active substance" as used herein may relate to a physiologically
active
material, which is a material intended to achieve or enhance a physiological
response. The
active substance may for example be selected from nutraceuticals, nootropics,
psychoactives.
The active substance may be naturally occurring or synthetically obtained. The
active substance
may comprise for example nicotine, caffeine, taurine, theine, vitamins such as
B6 or B12 or C,
melatonin, cannabinoids, or constituents, derivatives, or combinations
thereof. The active
substance may comprise one or more constituents, derivatives or extracts of
tobacco, cannabis
or another botanical.
The aerosol-former material may comprise one or more constituents capable of
forming
an aerosol. In some examples, the aerosol-former material may comprise one or
more of
glycerol, propylene glycol, diethylene glycol, triethylene glycol,
tetraethylene glycol, 1,3-butylene
glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl
suberate, triethyl citrate,
7
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate,
tributyrin, lauryl acetate,
lauric acid, myristic acid, and propylene carbonate.
The one or more other functional materials may comprise one or more of pH
regulators,
colouring agents, preservatives, binders, fillers, stabilizers, and/or
antioxidants.
As used herein, the term "component" is used to refer to a part, section,
unit, module,
assembly or similar of an electronic cigarette or similar device that
incorporates several smaller
parts or elements, possibly within an exterior housing or wall. An electronic
cigarette may be
formed or built from one or more such components, and the components may be
removably or
separably connectable to one another, or may be permanently joined together
during
manufacture to define the whole electronic cigarette. The present disclosure
is applicable to (but
not limited to) systems comprising two components separably connectable to one
another and
configured, for example, as a consumable/article component capable of holding
an aerosol
generating material (also referred to herein as a cartridge, cartomiser or
consumable), and a
device/control unit having a battery for providing electrical power to operate
an element for
generating vapor from the aerosol generating material.
Figure 1 is a highly schematic diagram (not to scale) of an example
aerosol/vapor
provision system such as an e-cigarette 10. The e-cigarette 10 has a generally
cylindrical
shape, extending along a longitudinal axis indicated by a dashed line, and
comprises two main
components, namely a control or power component or section 20 and a cartridge
assembly or
section 30 (sometimes referred to as a cartomizer, or clearomiser) that
operates as a vapor
generating component.
The cartridge assembly 30 includes a reservoir 3 containing an aerosolisable
material
comprising a liquid formulation from which an aerosol is to be generated, for
example containing
nicotine. As an example, the aerosolisable material may comprise around 1 to
3% nicotine and
50% glycerol, with the remainder comprising roughly equal measures of water
and propylene
glycol, and possibly also comprising other components, such as flavourings.
The reservoir 3 has
the form of a storage tank, being a container or receptacle in which
aerosolisable material can
be stored such that the aerosolisable material is free to move and flow within
the confines of the
tank. Alternatively, the reservoir 3 may contain a quantity of absorbent
material such as cotton
wadding or glass fibre which holds the aerosolisable material within a porous
structure. The
reservoir 3 may be sealed after filling during manufacture so as to be
disposable after the
aerosolisable material is consumed, or may have an inlet port or other opening
through which
new aerosolisable material can be added. The cartridge assembly 30 also
comprises an
electrical aerosol generating component 4 located externally of the reservoir
tank 3 for
8
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
generating the aerosol by vaporisation of the aerosolisable material. In many
devices, the
aerosol generating component may be a heating element (heater) which is heated
by the
passage of electrical current (via resistive or inductive heating) to raise
the temperature of the
aerosolisable material until it evaporates. A liquid conduit arrangement such
as a wick or other
porous element (not shown) may be provided to deliver aerosolisable material
from the
reservoir 3 to the aerosol generating component 4. The wick has one or more
parts located
inside the reservoir 3 so as to be able to absorb aerosolisable material and
transfer it by wicking
or capillary action to other parts of the wick that are in contact with the
vapor generating
element 4. This aerosolisable material is thereby vaporised, to be replaced by
new
aerosolisable material transferred to the vapor generating element 4 by the
wick.
A heater and wick combination, or other arrangement of parts that perform the
same
functions, is sometimes referred to as an atomiser or atomiser assembly, and
the reservoir with
its aerosolisable material plus the atomiser may be collectively referred to
as an aerosol source.
Various designs are possible, in which the parts may be differently arranged
compared to the
highly schematic representation of Figure 1. For example, the wick may be an
entirely separate
element from the aerosol generating component, or the aerosol generating
component may be
configured to be porous and able to perform the wicking function directly (a
metallic mesh, for
example).
Arrangements of this latter type, where the functions of the vapor generation
and wicking
are combined in a single element, are discussed further below. In some cases,
the conduit for
delivering liquid for vapor generation may be formed at least in part from one
or more slots,
tubes or channels between the reservoir and the aerosol generating component
which are
narrow enough to support capillary action to draw source liquid out of the
reservoir and deliver it
for vaporisation. In general, an atomiser can be considered to be an aerosol
generating
component able to generate vapor from aerosolisable material delivered to it,
and a liquid
conduit (pathway) able to deliver or transport liquid from a reservoir or
similar liquid store to the
aerosol generating component by a capillary force.
Typically, the aerosol generating component is located within an aerosol
generating
chamber that forms part of an airflow channel through the electronic
cigarette/system. Vapor
produced by the aerosol generating component is driven off into this volume,
and as air passes
through the volume, flowing over and around the vapor generating element, it
collects the vapor
whereby it condenses to form the required aerosol. The volume can be
designated as a aerosol
generating chamber.
9
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Returning to Figure 1, the cartridge assembly 30 also includes a mouthpiece 35
having
an opening or air outlet through which a user may inhale the aerosol generated
by the aerosol
generating component 4, and delivered through the airflow channel.
The power component 20 includes a cell or battery 5 (referred to herein after
as a
battery, and which may be re-chargeable) to provide power for electrical
components of the e-
cigarette 10, in particular the aerosol generating component 4. Additionally,
there is a printed
circuit board 28 and/or other electronics or circuitry for generally
controlling the e-cigarette. The
control electronics/circuitry connect the vapor generating element 4 to the
battery 5 when vapor
is required, for example in response to a signal from an air pressure sensor
or air flow sensor
(not shown) that detects an inhalation on the system 10 during which air
enters through one or
more air inlets 26 in the wall of the power component 20 to flow along the
airflow channel. When
the aerosol generating component 4 receives power from the battery 5, the
aerosol generating
component 4 vaporises aerosolisable material delivered from the reservoir 3 to
generate the
aerosol, and this is then inhaled by a user through the opening in the
mouthpiece 35. The
aerosol is carried from the aerosol source to the mouthpiece 35 along the
airflow channel (not
shown) that connects the air inlet 26 to the aerosol source to the air outlet
when a user inhales
on the mouthpiece 35. An airflow path through the electronic cigarette is
hence defined,
between the air inlet(s) (which may or may not be in the power component) to
the atomiser and
on to the air outlet at the mouthpiece. In use, the air flow direction along
this airflow path is from
the air inlet to the air outlet, so that the atomiser can be described as
lying downstream of the
air inlet and upstream of the air outlet.
In this particular example, the power section 20 and the cartridge assembly 30
are
separate parts detachable from one another by separation in a direction
parallel to the
longitudinal axis, as indicated by the solid arrows in Figure 1. The
components 20, 30 are joined
together when the device 10 is in use by cooperating engagement elements 21,
31 (for
example, a screw, magnetic or bayonet fitting) which provide mechanical and
electrical
connectivity between the power section 20 and the cartridge assembly 30. This
is merely an
example arrangement, however, and the various components may be differently
distributed
between the power section 20 and the cartridge assembly section 30, and other
components
and elements may be included. The two sections may connect together end-to-end
in a
longitudinal configuration as in Figure 1, or in a different configuration
such as a parallel, side-
by-side arrangement. The system may or may not be generally cylindrical and/or
have a
generally longitudinal shape. Either or both sections may be intended to be
disposed of and
replaced when exhausted (the reservoir is empty or the battery is flat, for
example), or be
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
intended for multiple uses enabled by actions such as refilling the reservoir,
recharging the
battery, or replacing the atomiser. Alternatively, the e-cigarette 10 may be a
unitary device
(disposable or refillable/rechargeable) that cannot be separated into two or
more parts, in which
case all components are comprised within a single body or housing. Embodiments
and
examples of the present invention are applicable to any of these
configurations and other
configurations of which the skilled person will be aware.
As mentioned, a type of aerosol generating component, such as a heating
element, that
may be utilised in an atomising portion of an electronic cigarette (a part
configured to generate
vapor from a source liquid) combines the functions of heating and liquid
delivery, by being both
electrically conductive (resistive) and porous. Note here that reference to
being electrically
conductive (resistive) refers to components which have the capacity to
generate heat in
response to the flow of electrical current therein. Such flow could be
imparted by via so-called
resistive heating or induction heating. An example of a suitable material for
this is an electrically
conductive material such as a metal or metal alloy formed into a sheet-like
form, i.e. a planar
shape with a thickness many times smaller than its length or breadth. Examples
in this regard
may be a mesh, web, grill and the like. The mesh may be formed from metal
wires or fibres
which are woven together, or alternatively aggregated into a non-woven
structure. For example,
fibres may be aggregated by sintering, in which heat and/or pressure are
applied to a collection
of metal fibres to compact them into a single porous mass.
These structures can give appropriately sized voids and interstices between
the metal
fibres to provide a capillary force for wicking liquid. Thus, these structures
can also be
considered to be porous since they provide for the uptake and distribution of
liquid. Moreover,
due to the presence of voids and interstices between the metal fibres, it is
possible for air to
permeate through said structures. Also, the metal is electrically conductive
and therefore
suitable for resistive heating, whereby electrical current flowing through a
material with electrical
resistance generates heat. Structures of this type are not limited to metals,
however; other
conductive materials may be formed into fibres and made into mesh, grill or
web structures.
Examples include ceramic materials, which may or may not be doped with
substances intended
to tailor the physical properties of the mesh.
A planar sheet-like porous aerosol generating component of this kind can be
arranged
within an electronic cigarette such that it lies within the aerosol generating
chamber forming part
of an airflow channel. The aerosol generating component may be oriented within
the chamber
such that air flow though the chamber may flow in a surface direction, i.e.
substantially parallel
to the plane of the generally planar sheet-like aerosol generating component.
An example of
11
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
such a configuration can be found in W02010/045670 and W02010/045671, the
contents of
which are incorporated herein in their entirety by reference. Air can thence
flow over both sides
of the heating element, and gather vapor. Aerosol generation is thereby made
very effective. In
alternative examples, the aerosol generating component may be oriented within
the chamber
such that air flow though the chamber may flow in a direction which is
substantially transverse
to the surface direction, i.e. substantially orthogonally to the plane of the
generally planar sheet-
like aerosol generating component. An example of such a configuration can be
found in
W02018/211252, the contents of which are incorporated herein in its entirety
by reference.
The aerosol generating component may have any one of the following structures:
a
woven or weave structure, mesh structure, fabric structure, open-pored fiber
structure, open-
pored sintered structure, open-pored foam or open-pored deposition structure.
Said structures
are suitable in particular for providing a aerosol generating component with a
high degree of
porosity. A high degree of porosity may ensure that the heat produced by the
aerosol
generating component is predominately used for evaporating the liquid and high
efficiency can
be obtained. A porosity of greater than 50% may be envisaged with said
structures. In one
embodiment, the porosity of the aerosol generating component is 50% or
greater, 60% or
greater, 70% or greater. The open-pored fiber structure can consist, for
example, of a non-
woven fabric which can be arbitrarily compacted, and can additionally be
sintered in order to
improve the cohesion. The open-pored sintered structure can consist, for
example, of a
granular, fibrous or flocculent sintered composite produced by a film casting
process. The open-
pored deposition structure can be produced, for example, by a CVD process, PVD
process or
by flame spraying. Open-pored foams are in principle commercially available
and are also
obtainable in a thin, fine-pored design.
In one embodiment, the aerosol generating component has at least two layers,
wherein
the layers contain at least one of the following structures: a plate, foil,
paper, mesh, woven
structure, fabric, open-pored fiber structure, open-pored sintered structure,
open-pored foam or
open-pored deposition structure. For example, the aerosol generating component
can be
formed by an electric heating resistor consisting of a metal foil combined
with a structure
comprising a capillary structure. Where the aerosol generating component is
considered to be
formed from a single layer, such a layer may be formed from a metal wire
fabric, or from a non-
woven metal fiber fabric. Individual layers are advantageously but not
necessarily connected to
one another by a heat treatment, such as sintering or welding. For example,
the aerosol
generating component can be designed as a sintered composite consisting of a
stainless steel
foil and one or more layers of a stainless steel wire fabric (material, for
example AISI 304 or
12
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
AISI 316). Alternatively the aerosol generating component can be designed as a
sintered
composite consisting of at least two layers of a stainless steel wire fabric.
. The layers may be
connected to one another by spot welding or resistance welding. Individual
layers may also be
connected to one another mechanically. For instance, a double-layer wire
fabric could be
produced just by folding a single layer. Instead of stainless steel, use may
also be made, by
way of example, of heating conductor alloys-in particular NiCr alloys and
CrFeAl alloys
("Kanthal") which have an even higher specific electric resistance than
stainless steel. The
material connection between the layers is obtained by the heat treatment, as a
result of which
the layers maintain contact with one another-even under adverse conditions,
for example during
heating by the aerosol generating component and resultantly induced thermal
expansions.
Alternatively, the aerosol generating component may be formed from sintering a
plurality of
individual fibers together. This, the aerosol generating component can be
comprised of sintered
fibers, such as sintered metal fibers.
The aerosol generating component may comprise, for example, an electrically
conductive thin layer of electrically resistive material, such as platinum,
nickel, molybdenum,
tungsten or tantalum, said thin layer being applied to a surface of the
vaporizer by a PVD or
CVD process, or any other suitable process. In this case, the aerosol
generating component
may comprise an electrically insulating material, for example of ceramic.
Examples of suitable
electrically resistive material include stainless steels, such as AISI 304 or
AISI 316, and heating
conductor alloys-in particular NiCr alloys and CrFeAl alloys ("Kanthal"), such
as DIN material
number 2,4658, 2,4867, 2,4869, 2,4872, 1,4843, 1,4860, 1,4725, 1,4765 and
1,4767.
As described above, the aerosol generating component may be formed from a
sintered
metal fiber material and may be in the form of a sheet. Material of this sort
can be thought of a
mesh or irregular grid, and is created by sintering together a randomly
aligned arrangement or
array of spaced apart metal fibers or strands. A single layer of fibers might
be used, or several
layers, for example up to five layers. As an example, the metal fibers may
have a diameter of 8
to 12 pm, arranged to give a sheet of thickness 0.16 mm, and spaced to produce
a material
density of from 100 g/m2 to 1500 g/m2, such as from 150 g/m2 to 1000 g/m2, 200
g/m2 to 500
g/m2, or 200 to 250 g/m2, and a porosity of 84%. The sheet thickness may also
range from
0.1mm to 0.2mm, such as 0.1mm to 0.15mm. Specific thicknesses include 0.10 mm,
0.11 mm,
0.12mm, 0.13 mm, 0.14 mm, 0.15 mm or 0.1 mm. Generally, the aerosol generating
component has a uniform thickness. However, it will be appreciated from the
discussion below
that the thickness of the aerosol generating component may also vary. This may
be due, for
example, to some parts of the aerosol generating component having undergone
compression.
13
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Different fiber diameters and thicknesses may be selected to vary the porosity
of the aerosol
generating component. For example, the aerosol generating component may have a
porosity
of 66% or greater, or 70% or greater, or 75% or greater, or 80% or greater or
85% or greater, or
86% or greater.
The aerosol generating component may form a generally flat structure,
comprising first
and second surfaces. The generally flat structure may take the form of any two
dimensional
shape, for example, circular, semi-circular, triangular, square, rectangular
and/ or polygonal.
Generally, the aerosol generating component has a uniform thickness.
A width and/or length of the aerosol generating component may be from about 1
mm to
about 50mm. For example, the width and/or length of the vaporizer may be from
1 mm, 2 mm,
3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm or 10 mm. The width may generally be
smaller
than the length of the aerosol generating component.
Where the aerosol generating component is formed from an electrically
resistive
material, electrical current is permitted to flow through the aerosol
generating component so as
to generate heat (so called Joule heating). In this regard, the electrical
resistance of the aerosol
generating component can be selected appropriately. For example, the aerosol
generating
component may have an electrical resistance of 2 ohms or less, such as 1.8ohms
or less, such
as 1.7ohms or less, such as 1.6ohms or less, such as 1.5ohms or less, such as
1.4ohms or
less, such as 1.3ohms or less, such as 1.2ohms or less, such as 1.1 ohms or
less, such as
1.00hm or less, such as 0.9ohms or less, such as 0.8ohms or less, such as
0.70hms or less,
such as 0.6ohms or less, such as 0.5ohms or less. The parameters of the
aerosol generating
component, such as material, thickness, width, length, porosity etc. can be
selected so as to
provide the desired resistance. In this regard, a relatively lower resistance
will facilitate higher
power draw from the power source, which can be advantageous in producing a
high rate of
aerosolization. On the other hand, the resistance should not be so low so as
to prejudice the
integrity of the aerosol generator. For example, the resistance may not be
lower than 0.5 ohms.
Planar aerosol generating components, such as heating elements, suitable for
use in
systems, devices and articles disclosed herein may be formed by stamping or
cutting (such as
laser cutting) the required shape from a larger sheet of porous material. This
may include
stamping out, cutting away or otherwise removing material to create openings
in the aerosol
generating component. These openings can influence both the ability for air to
pass through the
aerosol generating component and the propensity for electrical current to flow
in certain areas.
The reservoir of aerosolisable material can take on any shape and in some
examples
forms an annular shape surrounding the aerosol generation chamber and divided
therefrom by
14
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
a wall. The heating element generally extends across the aerosol generation
chamber and is
supported in place by its edges passing through the dividing wall or resting
in gaps in the wall.
In this way, edge portions of the heating element can be positioned in contact
with the reservoir
interior and can collect liquid therefrom by capillary action. This liquid is
then drawn into more
central portions of the heating element. Electrical connections are provided
on the heating
element which enable the passage of electrical current, producing the required
heating to
vaporise the liquid held in the porous structure of the heating element. Vapor
is delivered into
the aerosol generation chamber for collection by the flow of air along the
airflow channel.
Alternatively, as mentioned above, the heating current may comprise eddy
currents generated
by electromagnetic induction, requiring an electromagnet to produce a rapidly
alternating
magnetic field penetrating the aerosol generating component.
Figure 2 shows an exploded perspective view of various components of an
example
atomiser of this format. Figures 3 to 6 show perspective views of the
components represented
in Figure 2 at different stages of assembly.
The atomiser 160 comprises a first carrier component (first part) 101 and a
second
carrier component (second part) 102. These two components 101, 102 play a role
in supporting
a planar heating element 103, and in this regard may sometimes be referred to
as providing a
heating element cradle. Thus, the first and second components 101, 102
represented in Figure
2 may for convenience, and having regard to the orientation represented in the
figures, also be
referred to as an upper cradle 101 and a lower cradle 102. The atomiser 160
further comprises
the heating element 103, a first electrical contact element 104 for connecting
to a first end of the
heating element 103 and a second electrical contact element 105 for connecting
to a second
end of the heating element 103.
The upper and lower cradle components 101, 102 may be moulded from a plastics
material having a high glass fibre content (e.g. 50%) to provide improved
rigidity and resistance
to high temperatures, for example temperatures around 230 degrees centigrade.
The respective
upper and lower cradle components are broadly speaking of a generally semi-
circular cross-
section (although with variations in size and shape along their lengths as
discussed further
below). Each cradle component is provided with a recess 120 (only visible for
lower cradle
component 102 in Figure 2) running along its length on what would otherwise be
their flattest
faces so that when the two cradle components are brought together to sandwich
the heating
element 103 as discussed further below they form a cradle having a generally
tubular
configuration with an airflow path (defined by the respective recesses 120)
running down the
interior of the tube and in which the heating element 103 is disposed. The
airflow path formed
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
by the two recessed 120 comprises the aerosol generation chamber of the
atomiser 160. It is
noted that the cradle need not take on an elongate form, but may have width
and length
dimensions which are similar. Moreover, the dimensions of the respective
recesses 120 may
be varied as described further below.
The first and second electrical contact elements 104, 105 may be formed of a
sheet
metal material, for example comprising copper strips formed into an
appropriate shape having
regard to the shape and configuration of the other elements of the apparatus
in accordance with
conventional manufacturing techniques, or may comprise conventional flexible
wiring. Of
course, in examples where electrical energy is inductively coupled to the
heating element it will
be understood that such contact elements are not required.
The planar heating element 103 is formed from a sintered metal fibre material
and is
generally in the form of a sheet. However, it will be appreciated that other
porous conducting
materials may equally be used. In this particular example the heating element
103 comprises a
main portion 103A with electrical contact extensions 103B at each end for
connecting to the
respective electrical contact elements 104, 105. In this example, the main
portion 103A of the
heating element is generally rectangular with a longitudinal dimension (i.e.
in a direction running
between the electrical contact extensions 103B) of around 20 mm, and a width
of around 8 mm.
In the example of Figure 2, the longitudinal dimension corresponds to the
direction of
airflow through the vaporisation chamber (note that in other examples, the
longitudinal
dimension need not be the longest dimension of the heating element). The
thickness of the
sheet comprising the heating element 103 in this example is around 0.15 mm. As
can be seen
in Figure 2, the generally-rectangular main portion 103A of the heating
element 103 has a
plurality of openings in the form of slots extending inwardly from each of the
longer sides (sides
parallel to the longitudinal direction). The slots extend inwardly by around
4.8 mm and have a
width of around 0.6 mm. The slots extending inwardly are separated from one
another by
around 5.4 mm on each side of the heating element with the slots extending
inwardly from the
opposing sides being offset from one another by around half this spacing. In
other words, the
slots are alternately positioned along the longitudinal sides. A consequence
of this arrangement
of slots in the heating element is that current flow along the heating element
is in effect forced to
follow a meandering path which results in a concentration of current, and
hence electrical
power, around the ends of the slots. In this regard, and due to the presence
of the slots, the
heating element has been constructed such that some areas of the heating
element (in this
example the meandering path) have a greater propensity for current flow than
others.
16
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
The different current / power densities at different locations on the heating
element give
areas of relatively high current density that become hotter than areas of
relatively low current
density. This provides the heating element with a range of different
temperatures and increases
temperature gradients, which can be desirable in the context of aerosol
provision systems. This
is because different components of a source liquid may aerosolise / vaporise
at different
temperatures, so providing a heating element with a range of temperatures can
help
simultaneously aerosolise a range of different components in the source
liquid.
A process of assembling the components represented in Figure 2 to provide an
atomiser
160 such as for use in a cartridge assembly 30 of an electronic cigarette 10
is now described
with reference to Figures 3 to 6.
As can be seen in Figure 3, the first and second electrical contact elements
104, 105
have been mounted to the lower cradle component 102 and the heating element
103 is
represented above the lower cradle component 102 ready to be put in place. The
second
electrical contact element 105 is mounted at a second end of the lower cradle
component 102
(the leftmost end for the orientation in Figure 3). One end of the second
electrical contact
element 105 provides a second electrical contact element clamp portion 105A
for receiving one
of the electrical contact extensions 103B of the heating element 103 while the
other end of the
second electrical contact element 105 extends away from the lower cradle
component 102 as
shown in the figure. The first electrical contact element 104 is mounted so as
to run along the
length of the lower cradle component 102 adjacent a wall of the recess 120.
One end of the first
electrical contact element 104 extends away from the second end of the lower
cradle
component 102 as schematically represented in the figure. The other end of the
first electrical
contact element 104 provides a first electrical contact element clamp portion
105A arranged at a
first end of the lower cradle component 102 (rightmost end in Figure 3) for
receiving the other of
the electrical contact extensions 103B of the heating element 103.
An upper surface of the lower cradle component 102 comprises a plurality of
locating
pegs 110 which align with the slots in the heating element discussed above and
corresponding
locating holes in the upper cradle 101 (not shown in the figures). Although
not essential, these
locating pegs are for helping to align the upper cradle 101 with the lower
cradle 102, and for
helping to align the heating element 103 relative to the upper and lower
cradles 102 when
assembled.
Figure 4 shows the heating element 103 mounted to the lower cradle 102
containing the
first and second electrical contact elements 104, 105. The heating element 103
is mounted to
the lower cradle simply by being placed on the upper surface of the lower
cradle 102 with the
17
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
locating pegs 110 aligned with the slots of the heating element 103. Slightly
raised portions of
the upper surface of the lower cradle element 102 provide locating walls 111
in the vicinity of
the electrical contact extensions 103B at each end of the heating element 103
to further help
align the heating element. In this example, the locating walls are separated
by slightly more
than the size of the heating element and the locating pegs are slightly
smaller than the size of
the slots so the heating element is overall free to move slightly in the
horizontal plane, for
example by around 0.1 mm. This is to allow for thermal expansion and
contraction when the
heating element is in use to help avoid buckling. The first and second
electrical contact element
clamping portions 104A, 105A are bent down so as to clamp around respective
ones of the
electrical contact extensions 103B at each end of the heating element 103,
thus providing an
electrical connection between the portions of the electrical contact elements
104, 105 extending
away from the lower cradle component 102 and the ends of the heating element
103. In this
example the electrical connections between the electrical contact elements
104, 105 and the
heating element 103 rely solely on physical contact, but in other
implementations other
techniques may be used, for example welding or soldering.
Figure 5 shows the combined lower cradle component 102, first and second
electrical
contact elements 104, 105 and the heating element 103 as represented in Figure
4, but with the
other cradle component 101 shown ready to be mounted to the lower cradle
component.
Figure 6 schematically shows the upper cradle component 101 mounted to the
lower
cradle component 102 (and other elements represented in Figure 4) to provide
an assembled
atomiser 160. The upper cradle component 101 is mounted to the lower cradle
component 102
by simply placing them together with the locating pegs 110 of the lower cradle
component
aligned with corresponding locating holes (not shown) in the upper cradle
component 101. As
can be seen in Figures 4 and 5, the locating pegs 110 are each provided with a
shoulder 110A.
The shoulders 110A have a height above the upper surface of the lower cradle
component 102
that matches the height of the locating walls 111 but is slightly larger than
the thickness of the
heating element 103. The shoulders 110A are sized and arranged so as to fall
within the slots of
the heating element. However, the corresponding locating holes in the upper
cradle are sized
only to receive the locating pegs, and not their shoulders. Thus, when the
upper cradle
component 101 is mounted to the lower cradle component 102 they are separated
by a gap 205
corresponding to the height of the shoulders 110A and the locating walls 111.
The gap is
greater than the thickness of the heating element, so the heating element is
loosely sandwiched
between the upper and lower cradle components, rather than being fixedly
clamped in place. As
18
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
noted above, this loose mounting of the heating element is to allow for
thermal expansion and
contraction of the heating element during use.
Thus the assembled atomiser 160 is generally tubular with a central passageway
forming an aerosol generation chamber defined by the respective recesses 120
in the upper
and lower carrier components, providing an airflow path through the atomiser
that will connect
to an air inlet and an air outlet in a complete electronic cigarette. In use,
the particular atomiser
160 of Figure 6 is annularly surrounded by the reservoir of source liquid. The
gap 205 is in fluid
communication with the reservoir and hence provides a capillary channel (one
each side) which
extends along both sides of the heating element 103 and through which
aerosolisable material
may be drawn from the reservoir to the heating element where it enters the
pores of the heating
element for vaporisation to generate a vapor in the aerosol generation chamber
120 during use.
The passing air collects the vapor to generate an aerosol to be drawn out of
the vaporisation
chamber and along a further part of the airflow path through the electronic
cigarette 10 to exit
through the air outlet as a user inhales on the electronic cigarette 10.
When installed in an electronic cigarette, an atomiser may be arranged such
that the
longitudinal dimension of the heating element, corresponding to the direction
of airflow through
the atomiser from the upstream to downstream ends, is aligned parallel to the
longitudinal axis
of the electronic cigarette for an end-to-end device such as the Figure 1
example, or at least the
longitudinal axis of the cartridge component in a side-by-side device having a
power component
arranged to the side of a cartridge component. This is not compulsory,
however, and in the
current description, the term "longitudinal" is intended to refer to the
dimensions and orientation
of the atomiser, in particular the dimension of the heating element along the
airflow path from an
atomiser inlet at the upstream end of the atomiser, and through the
vaporisation chamber to the
atomiser outlet at the downstream end of the atomiser.
Figure 7 shows a highly simplified longitudinal cross-sectional side view of
the example
atomiser 160 in use, where the section is orthogonal to the plane of the
heating element 103.
The upper and lower cradle components 101 and 102 (or similar housing to form
the aerosol
generation chamber and support the heater) form outer walls which divide the
interior of the
atomiser 160 from the surrounding reservoir 3. The interior forms the aerosol
generation
chamber 120. The heating element 103, which is shown edge-on, extends
longitudinally through
the vaporisation chamber 120, and generates vapor into the aerosol generation
chamber as
discussed. An upstream end (shown left) of the aerosol generation chamber 120
connects with
an upstream part of the airflow channel through the electronic cigarette,
leading from one or
more air inlets (not shown in Figures 6 and 7). A downstream end (shown right)
of the
19
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
vaporisation chamber 120 connects with a downstream part of the airflow
channel, leading to
the mouthpiece air outlet. Consequently, when a user inhales through the air
outlet, air drawn in
through the inlet(s) enters the aerosol generation chamber 120 and follows a
longitudinal path,
able to flow over both surfaces of the planar heating element 103 before
recombining at the far
end to travel on to the air outlet. This is shown by the arrows A in the
figure. Accordingly, the
path length through the aerosol generation chamber 120 and over the heating
element surfaces
is relatively long, comprising effectively the full length of the heating
element 103. The flowing
air is hence able to collect a large amount of vapor, which condenses to form
aerosol droplets.
The airflow path through the atomiser 160 can influence the formation of
aerosol in the
aerosolization chamber and it has been found that certain configurations of
the aerosol
generating component (heater) with respect to the aerosol generating chamber
can lead to
variations in the size of aerosol particles formed. Such variations in
particle size may lead to
aerosols which are more acceptable to consumers.
There will now be described an aspect of the present disclosure relating to
the supply of
aerosolisable material to the aerosol generating component. In particular,
this aspect relates to
an article for use with an electrically operated non-combustible aerosol
delivery system, the
article comprising a generally planar aerosol generating component suspended
within an
aerosol generating chamber, wherein the periphery of the aerosol generating
component is
coupled to one or more feed apertures such that liquid aerosolisable material
may be fed
directly to the majority of the periphery.
In this regard, liquid being "fed directly" means that liquid reaching the
periphery does so
from a location outwardly, e.g. radially outwardly, of the periphery, rather
than reaching the
periphery as a result of internal movement from another location within the
aerosol generating
component.
In this regard, it is also noted that reference is generally made to liquid
aerosolisable
material being fed to the aerosol generating component in the context of this
aspect. This does
not preclude the aerosolisable material being in another state, e.g. a gel, in
another part of the
system and being converted to liquid for delivery to the aerosol generating
component.
In some embodiments, the aerosolisable material may be fed directly to
substantially all
of the periphery of the aerosol generating component. For example, the
aerosolisable material
may be fed directly to 80% or more of the periphery of the aerosol generating
component. For
example, the aerosolisable material may be fed directly to 90% or more of the
periphery of the
aerosol generating component. For example, the aerosolisable material may be
fed directly to
95% or more of the periphery of the aerosol generating component. In some
embodiments, the
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
aerosolisable material may be fed directly to the entirety of the periphery of
the aerosol
generating component.
Figure 8 shows a heating element 103a. Heating element 103a may be to be fed
with
aerosolisable material around the majority of its periphery. In this regard,
the periphery of the
heating element 103a is considered to be, for the heating element 103a, the
broadly rectangular
outer profile shown by dotted line P excluding the perimeter sections which
form the slots in the
heating element. Indeed, although heating element 103a includes slots, they
are not essential
in the context of the present aspect. As a result of being arranged to receive
aerosolisable
material around the majority of its periphery, it is possible to increase the
feeding of
aerosolisable material to the heating element 103a relative to other heating
elements which are
only fed via one or two sides (such as the heating element 103 referred to in
Figures 2 to 7).
The ability to feed aerosolisable material around the periphery of the heating
element
103a has implications for the design of the cradle sections, the coupling of
electrical energy to
the heating element, and also the aerosol generating chamber of the article.
For example,
electrical contact with the heating element may be effected through means
other than the
electrical contact extensions 103B, such as via electrical contacts embedded
in the cradle
sections as appropriate. Alternatively, where energy is inductively coupled to
the heating
element it will be understood that no electrical contacts are in fact
required, and this is another
advantage of configuring the aerosol generating component such that it is
configured to be fed
with aerosolisable material around its entire periphery.
Delivery of the aerosolisable material directly to the periphery of the
aerosol generating
component may be achieved in a number of ways. In some embodiments, the
aerosolisable
material is fed to the periphery of the aerosol generating component 103 in a
plane which is
parallel to the plane of the aerosol generating component. Such a feed
arrangement is shown in
Figure 8a. In some embodiments, the aerosolisable material is fed to the
periphery of the
aerosol generating component 103 substantially orthogonally to the plane of
the aerosol
generating component. Such a feed arrangement is shown in Figure 8h.
In some examples, the at least one feed aperture is a capillary gap. The
capillary gap
may be formed in a wall of the aerosol generating chamber. The capillary gap
may extend
around the aerosol generating chamber in a plane parallel to the plane of the
aerosol generating
component. In some examples, the capillary gap extends around at least 90% of
the perimeter
of the aerosol generating component. The capillary gap may extend
intermittently around the
aerosol generating chamber. Alternatively, the capillary gap may extend
continuously around
the aerosol generating chamber.
21
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Figure 8c shows an embodiment whereby the aerosol generating component is fed
with
aerosolisable material via a capillary gap. In particular, aerosol generating
component 103a is
shown has having a generally rectangular profile. Above and below aerosol
generating
component 103a are capillary forming elements 170 and 180. Each capillary
element has a
profile which generally corresponds to that of the aerosol generating
component 103a. Thus, in
this example the profile is generally rectangular, but it will be understood
that when the profile of
the aerosol generating component varies then the profile of the capillary
forming elements 170,
180 can vary accordingly. In a similar fashion to that described above with
respect to cradles
101 and 102, in use capillary forming elements 170 and 180 are arranged just
above and below
the aerosol generating component 103a such that the perimeter of the aerosol
generating
component 103a is located in a capillary gap formed by the capillary elements.
Due to the
profile of the capillary elements generally corresponding to that of the
aerosol generating
component 103a, the capillary gap can extend around the entire periphery of
the aerosol
generating component. This can allow for liquid to be fed to the entire
periphery of the aerosol
generating component 103a.
Capillary forming elements 170 and 180 can form part of the wall which defines
the
aerosol generating chamber, or can alternatively form part of a capillary
frame which is located
within the aerosol generating chamber. The capillary frame might take any
shape conforming to
the perimeter of the aerosol generating component. For example, where the
aerosol generating
component is circular, the frame may take the form of a torus extending around
the perimeter of
the aerosol generating component. For example, as shown in Figure 9a, the
aerosol generating
component 103a is located within a capillary frame 190. The aerosol generating
component
103a extends into a capillary gap (not shown) formed in the frame. The frame
is then fed with
aerosolisable material via one or more capillary conduits 181, 182. The
capillary conduits
181,182 are in fluid communication with the system reservoir and thus provide
a route for liquid
aerosolisable material to travel from the reservoir to the capillary frame and
thus to the aerosol
generating component. By locating the aerosol generating component in such a
capillary frame
it is possible to ensure that liquid is fed directly to the entire periphery
of the aerosol generating
component, whilst at the same time allowing for airflow to be channelled
across the surface of
the aerosol generating component 103a. Such a frame 190 (which can be a single
piece or
formed from two or more capillary frame elements) can be located within an
aerosol generating
chamber 200. In order to ensure that the frame does not significantly disrupt
the airflow over
the aerosol generating component, it may be that the total frame thickness HF
is less than 20%
of the total height H3 of the aerosol generating chamber 200 as is illustrated
in Figure 9b.
22
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Preferably the frame height is minimised so as to cause a minimal amount of
disruption to the
airflow flowing across the aerosol generating component.
In some examples where the air flow is across the surface of the aerosol
generating
component such that it has to by-pass the capillary frame, the frame may have
a profile which
influences the velocity of the airflow across it. For example, as shown in
Figure 9c, frame 190a
is provided with a leading face 192. Face 192 projects towards air entering
the aerosol
generating chamber and thus the geometry of face 192 can influence the
resultant downstream
flow of air. In Figure 9c, face 192 is shown as having a profile similar to
that of the leading edge
of an aircraft wing, e.g. it may be configured as an aerofoil. As incoming air
(shown by the
arrows in Figure 9c) flows over the face 192, the different in profile between
section 191 and
193 of the face 192 results in air travelling at different speeds. By changing
the profile of the
face 192 it is possible to influence the speed of the airflow over the aerosol
generating
component. Accordingly, in one broad aspect, there is provided an article
comprising an
aerosol generating component suspended within an aerosol generating chamber,
wherein
airflow travelling through the chamber and over the surface of the aerosol
generating
component has been influenced by an aerofoil shaped component. It will be
appreciated that in
Figure 9c the aerofoil shaped component is the leading edge of the capillary
frame but it will be
appreciated that other aerofoil shaped components could be located within the
chamber/at the
air inlet so as to influence the airflow. It is also possible that the
trailing edge of the capillary
frame may be provided with a profile which modifies the velocity of the
airflow across it.
In other examples, the at least one feed aperture is part of the wall of the
aerosol
generating chamber. Figure 10a shows a cross-section through an annular
reservoir 3
configured such that the central aperture through the reservoir forms the
aerosol generating
chamber 200. As shown in Figure 10a, the aerosol generating component 103a can
be located
within a feed aperture forming a capillary gap 205a which is in fluid
communication with the
reservoir 3. The internal walls of the reservoir 3a also serve to form the
aerosol generating
chamber 200 which forms part of the airflow channel through the device. It
will be understood
that in this embodiment airflow is configured to pass through the aerosol
generating component
rather than across its surface as shown by the direction of the arrows.
It is also envisaged that the at least one feed aperture could be located
outside of the
plane of the aerosol generating component. For example, and as illustrated
schematically in
Figures 10b and 10c, the aerosol generating component 103a is located at the
base of the
reservoir 3 such that a feed aperture 205b is located in proximity to the
periphery P of the
aerosol generating component 103a. This arrangement allows for direct gravity
feeding to the
23
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
periphery of the aerosol generating component without the need to arrange the
feed aperture in
the form of a capillary gap. This can be advantageous as lesser manufacturing
tolerances are
required when forming the gravity fed aperture compared to the capillary gap.
In Figure 10b, the
reservoir has been depicted having a base 3b. This can be useful so as to
minimise leakage
from the reservoir. Airflow in this embodiment can be arranged by providing
the base 3b with
one or more airflow apertures (not shown), in which case they could be equated
to air inlets into
the aerosol generating chamber. Alternatively, air flow can be directed so
that air passes past
the ends of the reservoir 3 so as to entrain aerosol as shown by the arrows in
Figure 10b.
It is also envisaged that the feed of aerosolisable material can be correlated
to certain
areas of the aerosol generating component. Thus, in another aspect of the
present disclosure,
the aerosol generating component is fluidly coupled to at least one component
for transferring
aerosolisable material to the aerosol generating component such that
aerosolisable material is
preferentially delivered to portions of the aerosol generating component
configured to vaporise
the aerosolisable material at a higher rate than other areas of the aerosol
generating
component. For example, aerosolisable material is preferentially fed to those
areas of the
aerosol generating component which are configured to dissipate higher energy
during use, e.g.
in the form of higher temperature. Such higher energy dissipation may result
from more power
being provided to a particular portion of the aerosol generating component.
Such areas of
greater power will have a propensity to convert the aerosolisable material to
a vapor more
rapidly than those areas with a lower power. Thus, and where for example
aerosolization
occurs via resistive heating, by matching the feeding of aerosolisable
material to those areas
with the greatest rate of vaporisation, a more efficient system can be
provided with less risk of
overheating the aerosolisable material.
In some examples, the at least one component for transferring aerosolisable
material is
selected from a wick, a pump, or a capillary gap. In some examples, the
portions of the aerosol
generating configured to vaporise the aerosolisable material at a higher rate
than other areas of
the aerosol generating component, are areas which are configured to be heated
to a higher
temperature during use. An example of an aerosol generating component
configured such that
some areas/portions are configured to dissipate more energy during use
compared to other
areas/portions is an aerosol generating component having portions with a
relatively greater
propensity for flow of electrical current. When an electrical current is
passed through such an
aerosol generating component, current will preferentially flow through those
portions having a
high propensity for electrical current flow. This will lead to greater
resistive heating in those
areas compared to others and thus greater power dissipation due to P = I2R.
24
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
In some examples, the portions of greater and lesser propensity for current
flow are
generated by creating areas of extremely high resistance in the aerosol
generating component.
For example, the aerosol generating component can be provided with apertures
or slots (as
described above) which effectively serve to prevent current flow. If, for
example, such apertures
or slots extend from the perimeter of the aerosol generating component,
electrical current will
preferentially flow through more central regions of the aerosol generating
component and those
areas will be subject to greater resistive heating.
In some examples where the aerosol generating component has portions of
greater and
lesser rates of vaporisation, this may result from the portions having
different densities.
In some examples, the portions having greater and lesser propensity for the
flow of
electrical current are formed from different materials.
The particular shape of the portions having greater or lesser propensity for
current flow
(or indeed rate of vaporisation in the broadest aspect) is not particularly
limited and can be
chosen based on other factors such as the configuration of the airflow through
the aerosol
generating chamber.
Figure lla shows an example of an aerosol generating component 103d having
portions
with a greater propensity for electrical current flow. In particular, Figure
lla shows an aerosol
generating component formed from a material such as stainless steel. The
aerosol generating
component 103d has a capillary structure by virtue of it being formed from a
plurality of stainless
steel fibres which have been sintered together such that the interstices
between the fibres form
a capillary structure. The capillary structure is not, however, visible in
Figure 11a. The aerosol
generating component 103d comprises a plurality of slots 130. These slots are
as described
elsewhere in the present disclosure. It is noted that the presence of the
slots is not essential
and they may be omitted, but in this embodiment they serve to create portions
having a greater
propensity for electrical current flow. The aerosol generating component 103d
also includes an
area having a greater propensity for electrical current flow 114 and an area
having a lesser
propensity for electrical current flow 115. In the embodiment of Figure 11a,
the areas having a
greater propensity for electrical current flow 114 take a serpentine shape and
result from the
presence of slots 130 which serve to influence the preferred flow of
electrical current through
the aerosol generating component 103d. In particular, the flow of electrical
current will be
greatest in proximity to the rounded apexes 133 of each slot 130a. The
specific configuration of
the slots may vary as explained more generally in the present disclosure.
As has been explained above, in some examples it can be desirable to
preferentially
deliver aerosolisable material to said portions having a greater propensity
for current flow. This
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
can be achieved in a number of ways. For example, a component for transferring
aerosolisable
material can be configured to preferentially deliver aerosolisable material to
the desired areas.
In some examples, the component for transferring aerosolisable material
comprises a wick (or a
plurality of wicks) and the (or each) wick contacts the portions having a
greater propensity for
current flow. In this way, aerosolisable material can be delivered directly to
those portions
having a greater propensity for current flow rather than having to flow
through the other areas of
the aerosol generating component as is the case for the embodiment described
in Figures 2 to
6.
Alternatively, if a pump or other mechanical means is used as the component
for
transferring aerosolisable material, the pump can be configured so as to
deliver liquid at a faster
rate to portions having a greater propensity for current flow (or indeed
energy dissipation) than
to other sections.
Alternatively, if a capillary gap is used as the component for transferring
aerosolisable
material, the capillary gap can be configured so as to have its edge located
in proximity to the
portions having a greater propensity for current flow. Thus, contrary to the
embodiments of
Figures 2 to 10 where aerosolisable material must flow through the outer
sections of the aerosol
generating component 103 in order to reach the central areas having a greater
temperature, in
the present embodiment it is possible for aerosolisable material to be
delivered directly in
proximity to portions having a greater propensity for current flow. Such an
arrangement is
shown in Figure 11a. In Figure 11a there is depicted in outline the edge of a
continuous
capillary gap 205. The capillary gap 205 takes a serpentine or zig-zag shape
with the ends and
points of inflection being located in proximity to the apexes 133 of each
slot. By configuring the
capillary gap 205 to track the portions having a greater propensity for
current flow, it is therefore
possible to allow aerosolisable material to by-pass the portions of the
aerosol generating
component having a lesser propensity for current flow.
Referring now to Figure 12, there is shown a schematic plan view of aerosol
generating
component 103a extending into a capillary gap 205 of a capillary frame 190.
The capillary gap
205 has a mouth section 206 and a body section 207. As can be seen, the
aerosol generating
component 103a extends past the mouth section 206 and into the body section
207. The mouth
section is formed by an edge which is non-linear. It will be appreciated that
the edge of the
mouth section may take other forms so as to correspond to the portions having
a greater
propensity for current flow. In some examples the edge may be circular (as
depicted in Figure
10c), elliptical, sinusoidal or polygonal. The periphery of the aerosol
generating component
103a extends into the body 207 of the capillary gap such that the mouth
section 206 of the
26
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
capillary gap 205 is in proximity to the boundary between the portions having
greater and lesser
propensity for the flow of electrical current.
It will be understood that this aspect of the present disclosure is not
limited to aerosol
generating components which are heated by electrical resistance heating, but
also extends to
other aerosol generating components having portions with respective greater
and lesser rates of
vaporisation.
In this regard, the portions having a greater rate of vaporisation may be
disposed,
relative to the longitudinal axis of the aerosol generating component,
inwardly of the portions
having a lesser rate of vaporisation. The portions having a lesser rate of
vaporisation may be
disposed at the periphery of the aerosol generating component.
Alternatively, the portions having a greater rate of vaporisation may be
disposed, relative
to the longitudinal axis of the aerosol generating component, outwardly of the
portions having a
lesser rate of vaporisation. The portions having a greater rate of
vaporisation may be disposed
at the periphery of the aerosol generating component.
The boundary between the portions having greater and lesser rates of
vaporisation
(propensity for the flow of electrical current) may be linear or non linear.
In some examples the
boundary is circular, elliptical, sinusoidal or polygonal.
It is further envisaged that the air inlet into the aerosol generating chamber
is arranged
so as to align with specific sections of the aerosol generating component.
Thus, in another
aspect of the present disclosure, there is provided an article for use with an
electrically operated
non-combustible aerosol delivery system, the article comprising a generally
planar aerosol
generating component suspended within an aerosol generating chamber, the
aerosol
generating component having a portion configured to vaporise aerosolisable
material at a higher
rate than other portions of the aerosol generating component, wherein said
chamber has an air
inlet and one or more air outlets defining a flow path therebetween, the flow
path being
arranged to track said portion of the aerosol generating component configured
to vaporise
aerosolisable material at a higher rate than other portions of the aerosol
generating component.
For example, the air inlet and outlet are preferably arranged with respect to
the aerosol
generating component such that the flow path between the inlet and outlet is
preferentially
distributed over those portions of the aerosol generating component which are
configured to
vaporise aerosolisable material at a greater rate during use. For example,
such portions may
be configured to dissipate greater power during use and thus have the
potential to reach a
higher temperature during use (and thus which are configured to vaporise
aerosolisable
material at a higher rate). Such higher temperature areas will have a
propensity to convert the
27
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
aerosolisable material to a vapor more rapidly than those areas with a lower
temperature. By
preferentially arranging the flow path with those areas of the aerosol
generating component with
the greatest ate of vaporisation, a more efficient system can be provided. In
this regard, the
flow path may be understood as the direct path between inlet and outlet in the
sense of being
the shortest linear path between then inlet and outlet, and thus may be
referred to as the "direct
flow path". Reference to "arranged to track" means that the majority of the
direct flow path is
within the area to be tracked. For example, where the aerosol generating
component and the
inlet and outlet are positioned at respective longitudinal ends of the
component so that the direct
flow path between the inlet and outlet will extends parallel to the aerosol
generating component,
the the direct flow path is arranged to travel directly above (or beneath)
those portions of the
aerosol generating component which are configured to vaporise aerosolisable
material at a
greater rate during use In some examples, more than 60% of the direct flow
path is within the
area to be tracked. In some examples, more than 65% of the direct flow path is
within the area
to be tracked. In some examples, more than 70% of the direct flow path is
within the area to be
tracked. In some examples, more than 80% of the direct flow path is within the
area to be
tracked. In some examples, more than 85% of the direct flow path is within the
area to be
tracked. In some examples, more than 90% of the direct flow path is within the
area to be
tracked.
Any of the above examples of aerosol generating components configured such
that
some areas/portions are configured to vaporise aerosolisable material faster
than other areas,
e.g. by reaching a higher temperature during use compared to other
areas/portions, may be
employed in the context of the present aspect. For example, an aerosol
generating component
having portions with a greater propensity for flow of electrical current may
be used. As
explained above, when an electrical current is passed through such an aerosol
generating
component, current will preferentially flow through those areas having a
higher propensity for
electrical current flow. This will lead to greater resistive heating in those
areas compared to
others.
Referring in this regard to Figure 13, an aerosol generating chamber 200 of an
aerosol
delivery system is shown. Generally, the aerosol delivery system comprises an
aerosol
generating component 300 located within, or in proximity to, the aerosol
generation chamber
200. The aerosol generation chamber 200 generally comprises an inlet 201 and
an outlet 202,
which together facilitate airflow "A" through the aerosol generation chamber.
During use of the
system, aerosolisable material (not shown), is energized so as to form a vapor
"V". The
produced vapor undergoes condensation in the aerosol generation chamber such
that particles
28
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
"Pa" are formed and entrained in the airflow through the chamber. Such
particles entrained in
the airflow form the aerosol of the aerosol delivery system. It will of course
be appreciated that
the aerosol is also composed of non-condensed vapor "V" and for particular
systems there will
be a particular partitioning between the particles and the vapor making up the
aerosol. Thus, it
is generally understood that for a condensation aerosol, there will be a
"particulate phase" and a
"gas or vapor phase".
Referring now to Figure 13a, an aerosol generating chamber 200a is shown.
Similarly to
aerosol generating chamber 200, aerosol generating chamber 200a comprises an
air inlet 201a
and an air outlet 202a. Aerosol generating component 300a is shown suspended
within aerosol
generating chamber 200a. In this regard, the term "suspended" generally refers
to the aerosol
generating component forming a bridge from one side of the aerosol generating
chamber to
another. As will be apparent from Figure 13a, inlet 201a and outlet 202a are
both located on
the same side of the aerosol generating component. Thus, air travelling
between the inlet 201a
and outlet 202a does so in an orientation that is generally aligned with the
longitudinal extent of
the aerosol generating component 300a. Indeed, the airflow travels generally
along a surface of
the aerosol generating component 300a. Such an airflow configuration may be
referred to as
"parallel" airflow, since the airflow is generally parallel to the surface of
the aerosol generating
component. A similar arrangement is shown with respect to Figure 7 above.
Air inlet 201a may take a range of shapes, as described below. However, in
some
examples the largest lateral dimension Ad of the air inlet 201a is less than
the width W of the
aerosol generating component 300a. Moreover, the air inlet 201a is located in
the aerosol
generating chamber 200d such that it is generally positioned in alignment with
the portion of the
aerosol generating component configured to vaporize aerosolisable material at
a higher rate
than other portions of the aerosol generating component. In some examples,
said portion
having a higher rate of vaporization is located towards the center of the
aerosol generating
component. In some examples, said portion having a higher rate of vaporization
301 spans a
lateral extent of the aerosol generating component as shown in Figure 13b. The
portion 301
has a width P, which is less than the width W of the aerosol generating
component 300a. The
air inlet 201a is aligned with the portion 301 such that the perimeter of air
inlet 201a is within the
boundaries of the portion 301. In general, P, is greater than Ad, since this
ensures that the air
inlet 201a is within the portion 301.
Turning to Figure 14a, air inlet 201a in aerosol generating chamber 200d is
formed by
two discrete apertures 205d and 206d respectively. Aerosol generating
component 300d is
visible in Figure 2a via aperture 205d. In this example, aerosol generating
component 300d is
29
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
located such that the surface of aerosol generating component 300d is
horizontal (at 90 to a
common axis through each of apertures 205d and 206d), and is equidistant from
apertures
205d and 206d. Due to the displacement of apertures 205d and 206d away from
the surface of
the aerosol generating component, air entering chamber 200d generally does so
at a distance
from the surface of the aerosol generating component. Aerosol generating
component 300d
projects into capillary gap 400d so as to enable feeding of aerosolisable
liquid from the store of
aerosolisable material (as described generally above). The reservoir of
aerosolisable material
may surround the aerosol generating chamber, such that the walls of the
aerosol generating
chamber form an inner wall of the reservoir and an outer wall of the article
forms an outer wall of
reservoir. By ensuring air enters the chamber at a distance from the surface
of the aerosol
generating component, the particle size of the resulting aerosol can be
controlled so as to be
relatively larger than when air enters at a point which is closer to the
surface of the aerosol
generating component. Moreover due to the location of the apertures 205d and
206d, the air
inlets are aligned with the portion of the aerosol generating component 300d
having a greater
rate of vaporization.
It has also been surprisingly found that by configuring the position of the
air inlet relative
to the aerosol generating component, it is possible to influence the size of
the particles formed
in the aerosol generation chamber. Controlling the size of the particles is
considered to be
important in connection with aerosol delivery systems used as simulated
cigarettes, such as e-
cigarettes or related devices as described herein. This is because the user
expects a certain
sensorial experience to be associated with the use of such a system and this
experience will be
influenced by the size of the particles present in the aerosol. In this
regard, relatively smaller
particles may not be deposited greatly in the buccal cavity of the user and
instead are deposited
predominately further along the respiratory system. By contrast, relatively
larger particles may
be more likely to be deposited in the buccal cavity of the user and with
relatively less deposition
occurring further along the respiratory system.
Further, it has been surprisingly found that by configuring the position of
the air inlet
relative to the aerosol generating component, it is possible to influence the
total amount of
aerosol delivered by the system. Controlling the amount of aerosol delivered
to the user is
considered to be important in connection with aerosol delivery systems used as
simulated
cigarettes, such as e-cigarettes or related devices as described herein. This
is because the
user is able to perceive the amount of aerosol delivered per inhalation and
associate a
particular sensorial experience with that amount. For example, inhalations
that are considered
to have a relatively high amount of aerosol may be perceived by the user to
provide a more
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
fulsome mouthfeel. Additionally, for a given system and aerosolisable
material, increasing the
amount of aerosol per inhalation will result in an increase in the amount of
active compounds
delivered per inhalation. Moreover, increasing the total amount of aerosol
delivered to the user
per inhalation gives an indication of the efficiency of the system. Indeed, it
has been
surprisingly found that the position of the air inlet relative to the aerosol
generating component
can influence the amount of aerosol that is delivered from the system. For
example, it has been
found that it is possible to increase the amount of aerosol delivered by the
system even though
other parameters which might affect aerosol generation (such as type of
aerosolisable material,
power used to generate the aerosol) remain unchanged.
Figure 14b shows a further air inlet configuration in accordance with the
present
disclosure. In particular, air inlet 201e is formed in aerosol generating
chamber 200e. Air inlet
201e forms a single aperture which is shaped so as to bias the air entering
the chamber to be
distanced from the surface of the aerosol generating component. For example,
air inlet takes
the form of a "dumb-bell", "dog-bone", or "hour-glass" shape such that
aperture areas of
generally larger cross-sectional area are joined by an area of relatively
smaller cross-sectional
area. Aerosol generating component 300e projects into capillary gap 400e so as
to enable
feeding of aerosolisable liquid from the store of aerosolisable material (as
described above). As
will be appreciated, air entering the chamber will be delivered preferentially
to areas which are
at a greater distance along the normal from the surface of the aerosol
generating component. It
has been surprisingly found that by biasing air so as to be further from the
surface of the
aerosol generating component, the particle size can be increased.
Referring now to Figure 15, end on views of various air inlet configurations
are shown.
Each of Figures 15a, 15b and 15c show end on views of an external face of an
aerosol
generating chamber including an air inlet. It will be understood that in these
figures the external
face of the chamber has a circular cross section. However, the specific shape
of the aerosol
generating chamber is not limited in the context of the present disclosure.
Rather, what is
important is the placement of the aerosol generating component within the
chamber relative to
the distribution of the one or more air inlets. In particular, air inlet 201c
is formed by a circular
aperture and is located such that equal proportions of the aperture are
distributed above and
below the generally planar aerosol generating component 300c. Such a
configuration leads to
the majority of air entering the chamber through inlet 201c being distanced
relatively nearer to
the surface of the aerosol generating component. However, the air inlet 201c
is still configured
so as to be aligned with the portion of the aerosol generating component 300d
having a greater
rate of vaporization.
31
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
Figure 15b shows an air inlet configuration in accordance with the aerosol
generating
chamber shown in Figure 14a. In particular, air inlet 201d in aerosol
generating chamber 200d
is formed by two discrete apertures 205d and 206d respectively. Although the
aerosol
generating component 300d is not visible in Figure 15b, it is located such
that the surface of the
aerosol generating component is horizontal and equidistant from apertures 205d
and 206d.
Due to the displacement of apertures 205d and 206d away from the surface of
the aerosol
generating component, air entering chamber 200d generally does so at a
distance from the
surface of the aerosol generating component. By ensuring air enters the
chamber at a distance
from the surface of the aerosol generating component, the particle size of the
resulting aerosol
can be controlled so as to be relatively larger than when air enters at a
point which is closer to
the surface of the aerosol generating component.
Figure 15c shows an air inlet configuration in accordance with the aerosol
generating
chamber shown in Figure 14b. In particular, air inlet 201 is formed from a
single aperture which
is shaped so as to bias the air entering the chamber to be distanced from
surface of the aerosol
generating component. For example, air inlet can take the form of a "dumbbell"
or "dog-bone"
shape such that areas of generally larger cross-sectional area are joined by
an areas of
relatively smaller cross-sectional area. As will be appreciated, air entering
the chamber will be
delivered preferentially to areas which are at a greater distance along the
normal from the
surface of the aerosol generating component. It has been surprisingly found
that by biasing air
so as to be further from the surface of the aerosol generating component, the
particle size can
be increased. In this regard, tests were conducted to assess the impact of
varying the relative
position of the air inlet with respect to the aerosol generating component. In
particular, the
particle size (D50) of an aerosol produced from an electrically heated aerosol
generating
component as described generally with respect to Figures 2 to 7 located within
the chamber
was assessed. Particle size measurements were conducted using a Malvern
Spraytech
analyzer. The location and geometry of the air inlet relative to the aerosol
generating
component were varied and aerosols were produced at different power levels for
a range of
different electrical powers. In particular, the locations and geometries
depicted in Figure 15a,
Figure 15b and Figure 15c respectively were each assessed at different power
levels. The air
flow through the system was maintained for each inlet configuration. The air
outlet for the
system was a generally circular aperture located so as to be horizontally
bisected by the
generally planar aerosol generating component. The results are shown in Figure
15d. As can
be seen, when the air inlet was varied so as to bias delivery of air to a
greater distance from the
surface of the aerosol generating component the particle size was increased.
The increase in
32
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
particle size was maintained across a range of power levels. The increase in
particle size was
greatest for the system where the air inlet was positioned so that no air was
delivered in line
with the aerosol generating component (the inlet configuration of Figure 15b).
Comparing the
results for the inlet configuration of Figures 15b and 15c shows that when
more air is biased
away from the surface of the aerosol generating component, the particle size
can be increased.
Figures 16a to 16f show a range of different air inlet configurations that can
be adopted
so as to bias the distribution of air entering the chamber away from the
surface of the aerosol
generating component. In each case, the aerosol generating component 300f is
shown in
dotted line. Figure 16a show the air inlet 201f having a triangular aperture
cross-section, with
the apex of the triangle projecting towards the surface of the aerosol
generating component.
Figure 16b shows the air inlet 201f being formed a plurality of circular
apertures, the apertures
being arranged such that a greater number are located at a greater distance
from the surface of
the aerosol generating component. Figures 16c, 16d and 16e respectively show
air inlet 201f
configurations of rectangular, oval and circular aperture cross-sections.
Figure 16f shows a
single air inlet 201f with an "hour-glass" shape, with the neck of the "hour-
glass" traversing the
aerosol generating component.
The one or more air inlets of the aerosol generating chamber may span opposing
sides
of the generally planar aerosol generating component. Alternatively, the one
or more air inlets
of the aerosol generating chamber may be solely located on one side of the
aerosol generating
component. Such a configuration may be particularly suitable whereby vapor is
released from
only one surface of the aerosol generating component.
The air inlets and/or air outlets may form apertures having a cross-sectional
shape
selected from circular, semi-circular, triangular, square, rectangular and/ or
polygonal.
Exemplary aperture cross-sections may include slot, dumb-bell, hour-glass etc.
Where the air
inlet and/or air outlet is formed from a single aperture, and that aperture
spans opposing sides
of the aerosol generating component, the cross-sectional shape is selected so
as to
preferentially distribute air entering the chamber away from the surface of
the aerosol
generating component. For example, where the aperture cross-sections is a dumb-
bell, the
"neck" of the dumb-bell may be horizontally bisected by the aerosol generating
component.
The relative orientation between the one or more air inlets and the aerosol
generating
component may be fixed. Alternatively, the orientation between the one or more
air inlets and
the aerosol generating component may be capable of being modified by the user.
This may be
achieved by moving either the aerosol generating component, the one or more
air inlets or both.
Likewise, the geometry of the one or more air inlets may be modified so as to
alter their
33
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
aperture cross-section. Likewise, where there are multiple air inlets, it may
be possible to
modify the extent to which air enters through one or more of the inlets. For
example, one or
more of the air inlets may be reduced in effective cross-sectional area (or
closed completely) so
as to change the distribution of air entering the chamber. This has the
advantage of allowing
the user control over the distribution of air entering the chamber and thus
the particle size of the
produced aerosol.
The precise width Ad of the air inlet may vary as described above, but it may
be that the
air inlet has an aperture width of less than 1.5mm.
The one or more air inlets may be configured such that air entering the
chamber is
preferentially distributed away from the surface of the aerosol generating
component.
The aerosol generating chamber may comprise more than one air inlet. For
example,
the chamber may comprise two, three, four, five, six or more inlets. The
inlets may be evenly
located on respective sides of the generally planar aerosol generating
component, or may be
unevenly located on respective sides of the generally planar aerosol
generating component.
Having air inlets spanning both sides of the aerosol generating component may
be
advantageous where vapor is produced from each surface of the aerosol
generating component
and thus delivery of air to the proximity of both surfaces serves to increase
the aerosol delivered
by the device.
In this regard, the relative number, geometry and location of air inlets may
be selected
so as to alter the proportion of air being delivered to one side or other of
the generally planar
aerosol generating component (noting always that air entering the chamber is
preferentially
distributed away from the surface of the aerosol generating component). For
example, a
plurality of air inlets having a relatively smaller aperture cross-sectional
area may provide the
same overall aperture size as a single aperture having a relatively larger
cross-sectional area.
Where the aerosol generating chamber comprises more than one air inlet, they
may be
symmetrically oriented with respect to the plane of the aerosol generating
component.
Alternatively, where the aerosol generating chamber comprises more than one
air inlet, they
may be asymmetrically oriented with respect to the plane of the aerosol
generating component.
The article generally comprises one air outlet. However, the chamber may
comprise
more than one air outlet. For example, the aerosol generating chamber may
comprise two,
three, four, five, six or more outlets. It may be that the configuration of
the outlets matches the
configuration of the inlets. Alternatively, where there are multiple inlets,
there may only be one
outlet (or vice versa). At least a portion of the one or more air inlets may
be linearly aligned with
34
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
at least a portion of the one or more air outlets. This ensures that airflow
through the chamber
is preferentially linear and is not diverted to any significant extent through
the chamber.
According to another aspect of the present disclosure, the dimensions of the
aerosol
generating chamber are configured such that the velocity of air flow through
the chamber is in
the range of 0.05m/s to 25m/s. For example, the velocity may be 0.05m/s to
20m/s, 0.05m/s to
15m/s, 0.05m/s to 10m/s, 0.05m/s to 5m/s, 0.05m/s to 3m/s, 0.05m/s to 2m/s,
0.05nrils to
1.25m/s or 0.05m/s to 1m/s.
In particular, the above velocities may be imparted to the airflow through the
chamber
when a certain pressure drop is applied across the air inlet and air outlet of
the chamber. For
example, the pressure drop may be in a range of from 5mmWG to 120mmWG, such as
from
30mmWG to 90mmWG, 30mmWG to 80mmWG, 30mmWG to 70mmWG, 30mmWG to
60mmWG, 30mmWG to 50mmWG, or 30mmWG to 45mmWG. The above velocities may be
achieved at specific pressure drops, such as 30mmWG, 35mmWG, 40mmWG, 45mmWG,
50mmWG, 55mmWG, 60mmWG, 65mmWG, 70mmWG, 75mmWG, 80mmWG, 85mmWG,
90mmWG, 95mmWG, or 100mmWG. It has been found that by controlling the
dimensions of
the aerosol generating chamber such that the above velocity range is achieved,
the particle size
of an aerosol entrained in the airflow can be influenced positively.
In particular, there is provided an article for use with an electrically
operated non-
combustible aerosol delivery system, the article comprising an aerosol
generating chamber
having one or more air inlets and one or more outlets defining a flow path
therebetween, and a
generally planar aerosol generating component suspended within the aerosol
generating
chamber such that the flow path is substantially parallel to the plane of the
aerosol generating
component, wherein respective first and second faces of the aerosol generating
component
project towards corresponding first and second walls of the chamber, with each
wall being
distanced from its respective face such that the velocity of air across each
face is in the range
0.05m/s to 25m/s.
Figure 17a shows a cross sectional view of an article of similar construction
to that
shown in Figures 2 to 6. The section is shown along the longitudinal axis of
the article. Figure
17a shows an aerosol generating component 103a held between an upper cradle
101a and a
lower cradle 102a. The upper and lower cradles of Figure 17a are slightly
different to those
depicted in Figures 2 to 6 above, but their principles of construction and
liquid feeding to the
aerosol generating component 103a are the same. Similarly to the cradles of
Figures 2 to 6, a
recess 120a is provided in each cradle and together these recesses form the
aerosol generating
chamber 200 with the aerosol generating component 103a positioned therein. An
inner wall
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
1 01 b of the upper cradle and inner wall 102b of the lower cradle define the
recesses. The
aerosol generating component 103a is comprised of an upper face 103a' which
projects
towards upper cradle 101a and a lower face 103a" which projects towards the
lower cradle
102a. Air enters the aerosol generating chamber 200 via the air inlet 201a and
travels
substantially parallel to the upper and lower faces of the aerosol generating
component 103a.
It has been found that the velocity at which air flows through the aerosol
generating
chamber can influence the particle size of the aerosol produced. In
particular, greater velocities
have been found to be able to suppress the particle size growth of the
aerosol. In some
examples, the internal geometry of the aerosol generating chamber 200 is
configured to provide
for a velocity of air across each face of the aerosol generating component of
between 0.05m/s
to 25m/s. In order to achieved this, a pressure drop of from 5mmWG to 120mmWG
may be
applied across the air inlet and air outlet. One way of achieving this is to
configure the distance
between the inner walls 101b and 102b of the cradles, and the respective upper
and lower
faces of the aerosol generating component 103a' and 103a" appropriately. In
this regard,
Figure 17b shows a cross-section through the chamber 200 of Figure 17a
perpendicular to the
longitudinal axis of the article. The aerosol generating chamber 200 of
Figures 17a and 17b
generally has a square-cross section (noting the slightly rounded corners
shown in Figure 17b).
Although other cross-sections of chambers are possible, generally the cross-
section of the
chamber will be generally square or rectangular. The distance between the
upper face 103a'
and the upper wall 101b is shown by H1. The distance between the lower face
103a" and the
lower wall 102b is shown by H2. The total height between the upper and lower
walls 101b, 102b
is shown by H3. It has been found that by reducing Hi and H2 the velocity
through the chamber
200 can be increased such that particle size of the aerosol can be controlled.
In some
examples, H1 and H2 are the same. In some examples, H1 and H2 are different.
By choosing
different heights H1 and H2 it is possible to tailor the final particle size.
H1 and H2 may be the
same or different and have a value of less than 4m, less than 3m, or less than
2mm, such as
1.9mm, 1.8mm, 1.7mm, 1.6mm, 1.5mm, 1.4mm, 1.3mm, 1.2mm, 1.1 mm or about 1mm.
H3
may have a value of less than 8mm, less than 7mm, less than 6mm, less than
5mm, or less
than 4mm, such as 3.9mm, 3.8mm, 3.7mm, 3.6mm, 3.5mm, 3.4nnm, 3.3mm, 3.2mnn,
3.1 mm,
3.0mm, 2.9mm, 2.8mm, 2.7mm, 2.6mm, 2.5mm, 2.4mm, 2.3mm, 2.2mm, 2.1 mm or about
2mm.
It has been found that by controlling the respective distances mentioned
above, it is
possible to reduce the particle size of an aerosol produced by the system. In
particular, for a
system using the same aerosol generating component, aerosolisable material and
power
36
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
output, reducing each of H1 and H2 from 2mm to 1mm resulted in a significant
reduction in
aerosol particle size.
According to another aspect of the present disclosure, it has been found
possible to also
optimise the aerosol generating component. In particular, in some examples the
aerosol
generating component comprises a capillary structure, wherein the capillarity
of a first portion of
the capillary structure varies relative to the capillarity of a second portion
of the capillary
structure. The first portion and the second portion may have different rates
of vaporisation of
aerosolisable material. Thus, the capillarity of different portions of the
capillary structure varies
in accordance with the ability of the respective portion to effect
vaporisation of aerosolisable
material.
As has been described above, aerosol generating components can be prepared
whereby some portions of the aerosol generating component are able to effect
vaporisation of
aerosolisable material at a greater rate than other areas. This might be due
to the fact that
some portions of the aerosol generating component are configured to dissipate
more energy
during use (for example, by virtue of such portions having a higher propensity
for electrical
current flow). By varying the capillarity of such portions dependent on the
rate at which they are
able to effect vaporisation of aerosolisable material, it is possible to
provide that those portions
having a greater rate of vaporisation are able to be fed with aerosolisable
material in a more
optimised manner.
In this regard, it will be understood that the capillarity of a particular
capillary channel is a
function of the cross-sectional dimensions of that channel. Assuming the
channel to have a
generally circular cross-section, a relatively smaller radius will lead to a
relatively greater
capillarity. In some examples, the capillarity of the portions able to effect
vaporisation of
aerosolisable material at a greater rate is greater than the capillarity of
the portions able to
effect vaporisation of aerosolisable material at a lesser rate. Thus, where C
is capillarity, in
some examples Cportions of greater rate of vaporisation
> Cportions of lesser rate of vaporisation. Therefore, those
portions which vaporise aerosolisable material more quickly have a
correspondingly greater
capillarity. In some examples, the average pore size of the portions able to
effect vaporisation
of aerosolisable material at a greater rate is smaller than the average pore
size of the portions
able to effect vaporisation of aerosolisable material at a lesser rate. Thus,
there is also provided
an aerosol generating component having a capillary structure, wherein the
aerosol generating
component has portions having different average pore sizes. Thus, one or more
portions of the
aerosol generating component may have an average pore size in the range of
511m to 3011m,
and one or more other portions may have an average pore size which is
different and in the
37
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
range of 20 m to 40 m. Average pore size may be determined in this regard
using a digital
microscope, for example a VHX-6000 series from Keyence. For example, for each
particular
portion of sample being tested, the digital microscope assesses the size of
each pore in the
portion by distinguishing between the respective pores and fibres (using the
different contrast
imaged for pore and fibre). The pore sizes are then averaged over the portion
being measured.
In some examples where the aerosol generating component has areas of greater
and
lesser rates of vaporisation, the portions may have different densities. For
example, the
portions having a greater rate of vaporisation have a density of up to 300 %,
such as up to
250%, such as up to 250%, relative to the density of the portions having a
lesser rate of
vaporisation. The difference in density is typically reflective of a
difference in capillarity, with
areas of greater density typically having greater capillarity. The variations
in density may result
from sections of the aerosol generating component being compressed relative to
other sections.
This compression leads to a greater density (and thus reduced average pore
sizes and
increased capillarity).
Accordingly, there is also provided a method for producing an aerosol
generating
component having a capillary structure, the method comprising the steps of
providing an
aerosol generating component having a capillary structure, and compressing the
aerosol
generating component in one or more portions to increase the density in those
portions.
Compressing may be carried out as is known to the skilled person, e.g. by
using a stamp, roller
or the like.
Figure 11 b shows an example of an aerosol generating component 103e where the
capillarity of a portion of the capillary structure varies in accordance with
the ability of that
portion to effect vaporisation of aerosolisable material.
In particular, aerosol generating
component 103e is formed from stainless steel fibres which have been sintered
together to form
a generally planar component as described generally above. The aerosol
generating
component 103e has slots 130 as described elsewhere herein. The aerosol
generating
component 103e also comprises a portion of relatively greater capillarity 140a
and a portion of
relatively lesser capillarity 140b. The portion of relatively greater
capillarity 140a generally
coincides with the portion of the aerosol generating component able to effect
vaporisation of
aerosolisable material at a greater rate. In the example of Figure llb this is
achieved through
the use of slots 130 directing current flow, but this could also be achieved
in other ways as is
described herein.
As described herein, the aerosol generating component may comprise one or more
apertures which inhibit the flow of electrical current through therethrough.
Variations in aperture
38
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
shape, size and number are described throughout this document and such
variations in
aperture configuration can be applied to the present aspect. Similarly, the
present disclosure
describes how the aerosol generating component is configured to be fed with
aerosolisable
material. The various variations described with respect to transferring
aerosolisable material to
the aerosol generating component can be equally applied to this aspect.
In some examples, the portions having greater and lesser propensity for the
flow of
electrical current are formed from different materials. For example, portions
may be formed
from different materials selected from stainless steels, such as AISI 304 or
AISI 316, and
heating conductor alloys, in particular NiCr alloys and CrFeAl alloys. It is
also envisaged that the
number/geometry of the aperture/slot features of the aerosol generating
components described
herein may be varied so as to influence the airflow through the aerosol
generating component
and/or vaporisation profile of the aerosol generating component.
Thus, according to another aspect of the present disclosure, there is provided
an aerosol
generating component which comprises a plurality of differently sized
apertures. Any of the
aspects described herein may comprise an aerosol generating component with a
plurality of
differently sized apertures. In some examples, one or more of the apertures
may be slot
shaped. It may also be possible for one or more of the slot widths and/or
lengths to vary.
Generally, the one or more slots extend inwardly from the periphery of the
aerosol generating
component. Apertures or slots extending inwardly from the periphery of the
aerosol generating
component may reach or extend past the midpoint of the aerosol generating
component.
Apertures or slots may extend from opposite peripheral edges of the aerosol
generating
component. In this regard, it is to be understand that "apertures" or "slots"
does not include
surface or structural pores that may be present as an inherent part of the
aerosol generating
component. Rather, the terms "apertures" or "slots" mean openings which extend
continuously
from one surface of the generally planar aerosol generating component to the
opposite surface.
The slots may take a particular form, and an exemplary slot is shown in Figure
11b. For
example, each slot may have an opening 131, a body section 132 and an apex
133. Body
section 132 may be linear as shown in Figure 11b. However, it is also possible
for the body of
the slot to be non-linear, or wavy. The apex (or termination as referred to
above) 133 may be
rounded as shown in Figure 11b. However, other configurations are possible
such as angular,
oval or droplet shaped. An advantage of having different apex configurations
is that the apex
configuration can be modified to as to influence the flow of electrical
current in the aerosol
generating component. It is also possible to have combinations of apex
configurations, and/or
for the apex configurations to take the same overall shape but to be oriented
differently. Figure
39
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
9d provides an example of an aerosol generating component 103g having four
slots and a
circular apex 133, where the width of the circular apex is enlarged relative
to the width of the
slot. Figure 9e provides an example of an aerosol generating component 103g
having four slots
and a curved apex 133. Figure 9f provides an example of an aerosol generating
component
103g having two slots and a oval apex 133. Any combination of slot number and
apex
configuration is envisaged. For example, the aerosol generating component may
have one, two,
three, four, five or six slots. As shown in Figure 11 b, the opening 131 may
also be flared to an
extent.
In some embodiments, the number, size and shape of the apertures are
distributed
throughout the aerosol generating component so as to influence airflow in the
aerosol
generating chamber. For example, where airflow through the chamber is
configured to pass
through the aerosol generating component, the number, size and shape of the
apertures can be
selected so as to normalize airflow exiting the aerosol generating component.
By "normalize" it
is meant that airflow exiting the aerosol generating component is less
turbulent than airflow
approaching the aerosol generating component. For example, there is provided
an article for
use with an electrically operated non-combustible aerosol delivery system, the
article
comprising an aerosol generating chamber having one or more air inlets and one
or more
outlets defining a flow path therebetween, and a generally planar aerosol
generating component
suspended within the aerosol generating chamber such that the flow path is
substantially
transverse to the plane of the aerosol generating component, wherein the
aerosol generating
component comprises a plurality of differently sized apertures.
In another aspect of the present disclosure, it is envisaged that a
temperature profile
within the aerosol generating chamber varies from the one or more air inlets
to the one or more
air outlets.
In particular, it is envisaged that during activation of the aerosol
generating
component a first temperature profile having a negative gradient is
established along a portion
of the flow path from inlet to outlet. It has been surprisingly found that
when such a temperature
profile having a negative gradient is established, particle size growth of the
aerosol can be
suppressed. Therefore, by controlling the gradient of the temperature profile,
it is possible to
control the particle size of the aerosol, which can be positive from a
sensorial aspect.
Accordingly, there is provided an article for use with an electrically
operated non-
combustible aerosol delivery system, the article comprising a generally planar
aerosol
generating component suspended within an aerosol generating chamber, the
chamber having
one or more air inlets and one or more outlets defining a flow path
therebetween, wherein
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
during activation of the aerosol generating component a first temperature
profile having a
negative gradient is established along a portion of the flow path from inlet
to outlet.
By "temperature profile with a negative gradient" it is meant that a
temperature at an
upstream location of the aerosol generating chamber is greater than a
temperature at an
corresponding downstream location of the aerosol generating chamber. Thus, the
temperature
is generally higher at an upstream end of the chamber than at a downstream
end.
Typically, the aerosol generating component defines a longitudinal axis which
extends
along the flow path. In some examples, the negative temperature gradient is
established along
less than 50% of the flow path. In some examples, the negative temperature
gradient is
established along less than 20% of the flow path. In some examples, the
negative temperature
gradient is established along less than 5% of the flow path. In this regard,
for a given starting
temperature, limiting the extent to which the negative temperature gradient
extends influences
the rate at which the temperature drops within the chamber.
In some examples, the peak temperature is established in proximity to the one
or more
air inlet(s) of the aerosol generating chamber. For example, the peak
temperature may be
established within 20%, 15%, 10% or 5% from the opening of the air inlet(s)
into the aerosol
generating chamber. In this regard, the `)/0 proximity is based upon a linear
pathway from the air
inlet to the air outlet of the aerosol generating chamber.
Establishing a temperature profile with a negative gradient may be achieved in
a number
of ways. For example, it may be that an additional heater is located in
proximity to the one or
more air inlets such that incoming air is subjected to heating. As the airflow
moves through the
aerosol generating chamber it is subjected to relatively less heating than at
an upstream
location and subsequently cools thus establishing the negative temperature
gradient. Other
ways of establishing such a gradient will be apparent to the skilled person.
It should be noted in
this regard that under normal circumstances in prior art devices the airflow
that has travelled
past the heater will begin to cool and thus a negative temperature gradient
will be established at
some point in time over the total flow path. However, in the system described
herein, the
aerosol generating component is generally disposed parallel to the airflow
through the device.
This has the effect that incoming air is continually heated as it travels the
length of the aerosol
generating component. This is illustrated in Figure 18a, where the Y axis
represents the
temperature of the airflow as it travels a distance through the aerosol
generating chamber,
represented by the X-axis. Ta represents the temperature of the incoming
"ambient" air, and Tp
represents the peak temperature within the aerosol generating chamber of the
device. It will be
observed that the temperature of the airflow rises rapidly on entering the
aerosol generating
41
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
chamber and then continues to rise up to Tp due to the cumulative heating it
experiences. The
temperature of the air then drops rapidly upon exiting the aerosol generating
chamber. Figure
18b illustrates the temperature profile of an aerosol generating chamber
configured according to
the present aspect of the disclosure. Similarly to in Figure 18a, the
temperature rises rapidly
from Ta upon entry into the aerosol generating chamber. However, contrary to
in Figure 18a,
according to the present aspect Tp is established at an upstream location of
the aerosol
generating chamber. The temperature then decays along the chamber until the
same rapid
drop in temperature is experienced upon exit.
Other ways of establishing a negative temperature gradient within the chamber
are also
possible. For example, the aerosol generating component may be configured to
dissipate
greater energy, i.e. heat, at an upstream location relative to a downstream
location. This might
be achieved in a number of ways. For example, the aerosol generating component
may be
configured with a capillary structure at an upstream portion which has a
capillarity inferior in
terms of feed rate compared to a capillary structure at a corresponding
downstream portion.
This will result in aerosolisable material being fed less rapidly to the
upstream portion. Since the
presence of aerosolisable material effectively acts to moderate the
temperature of the aerosol
generating component during heating, where less aerosolisable material is
being provided there
will be a greater localised temperature. Alternatively, a similar effect can
be achieved by
configuring the aerosol generating component such that an upstream portion
experiences
relatively greater resistive heating than a corresponding downstream portion.
In some
examples, this is achieved by configuring an upstream portion of the aerosol
generating
component such that said portion has a higher resistance than a corresponding
downstream
portion. This higher resistance can, for example, be imparted to the portion
by forming said
portion of a material with a higher electrical resistance or by modifying the
geometry of said
portion. An example of the resistance being modified by modifying the geometry
is shown in
Figure 18c. Figure 18c shows an aerosol generating component 103g generally
similar to the
aerosol generating component 103 described above with respect to Figures 2 to
7. Thus,
aerosol generating component 103g is in this embodiment formed from stainless
steel fibres
which have been sintered together to form a generally planar aerosol
generating component
with a capillary structure. Aerosol generating component 103g has slots 130 as
also described
elsewhere. However, aerosol generating component 103g has an upstream portion
135 which
has an electrical resistance which is higher than that of a subsequent
downstream portion 136.
In this regard, although portions 135 and 136 are formed from the same
material and have the
same general structure, portion 135 has a width W1 which is smaller than the
width W2 of
42
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
portion 136. In general the width of the upstream portion will be constant,
but in some
examples the width of the upstream portions varies. For example, the width may
vary due to
the slot body being angular thus forming a somewhat tapered profile. It is
also possible that the
width of an upstream portion is reduced relative to other portions of the
aerosol generating
component as a result of a deviation in the perimeter of the aerosol
generating component at
the relevant portion. Thus, it may be that a notch or other indentation into
the aerosol
generating component restricts the width of the upstream portion. For example,
Figures 9d to
Figures 9f show examples of the aerosol generating components where a notch
137 is present
on the most upstream portion of the aerosol generating component (where the
direction of flow
is from left to right). The notch serves to restrict current flow through the
upstream portion and
therefore leads to an increase in resistance and thus heat generation. It will
be appreciated that
any form of notch, cut-out etc. can be formed in this portion provided that it
is sufficient to result
in an increase in the electrical resistance of the portion compared to the
next downstream
portion. In Figures 9d and 9f, notches 137 have a curved profile. In Figure
9e, the notch has a
somewhat liner profile. The dimensions and/or number of notches/cut-outs can
be varied so as
to achieve the desired electrical resistance of the upstream portion. It will
also be noted that in
Figures 9d to 9f there is a corresponding notch/cut-out at the downstream most
portion of the
aerosol generating component. This additional notch is provided so as to allow
for ease of
manufacturing. More particularly, by providing a notch/cut-out at the
respective most upstream
and most downstream portions of the component, it is possible to prepare an
aerosol generating
component that has a degree of rotational symmetry. This means that it is
easier to orientate
the aerosol generating component correctly during manufacture. Accordingly, in
a further
aspect, there is provided an aerosol generating component having a degree of
rotational
symmetry. The degree of rotational symmetry may be 2-fold. The aerosol
generating
component may be substantially flat or planar and the degree of rotational
symmetry is with
respect to the plane of the aerosol generating component. The aerosol
generating component
may comprise one or more apertures, such as slots as described herein. The
slots may
terminate at an apex. The apex may be take a variety of profiles as described
herein. The
aerosol generating component may be configured such that the electrical
resistance of the
component varies between an upstream portion and a downstream portion as
described herein.
In the specific example of Figure 18c, portion 135 has a constant width of
1.3mm and
portion 136 has a constant width of 2.0mm. Thus, in some embodiments the
ration of Wi to W2
less than 1, such as less than 0.9, less than 0.8, less than 0.7, or less than
0.6. Limits on the
ratio between portions may mean that a lower limit of the ratio may be about
0.5. As a result of
43
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
this ratio, electrical current passing through portion 135 experiences a
relatively greater
resistance compared to when it travels through portion 136. Since P = I2R, the
greater
resistance experienced through portion 135 leads to greater power being
distributed to portion
135. This greater power leads to a relatively increased temperature locally in
portion 135.
Moreover, this is exacerbated due to the relatively reduced amount of material
in portion 135
compared to portion 136, and thus there is less material in 135 to distribute
the relatively
increased power. Such a result leads to portion 135 being heated to a
temperature higher than
portion 136. Since further downstream portions 136, 138 and 139 are
dimensioned similarly to
portion 135, they will be heated to a similar extent as portion 136. Thus a
negative temperature
gradient is established from an upstream location to a downstream location.
Accordingly, in
some examples, the aerosol generating component has an upstream portion having
a relatively
greater electrical resistance than a subsequent downstream portion. In some
examples,
respective portions of the aerosol generating component may be defined by an
opening
extending from the perimeter of the aerosol generating component. The opening
may be a slot
which extends generally perpendicularly to the longitudinal axis of the
aerosol generating
component. As described above, the width of an upstream portion may be less
than the width
of a downstream portion. In some examples, the aerosol generating component
comprises two,
three, four, five or six portions. At least one of the upstream portions may
have a width less
than the width of a downstream portion. Alternatively, two or more of the
upstream portions
may each have a width less than the width of a portion downstream (of each of
the upstream
portions).
In some examples, the temperature gradient may be divided into two or more
segments
having different gradients of temperature change. Each segment may comprise
one or more
upstream/downstream portions as described above in the context of portions 135
to 139. Thus,
a second or subsequent temperature profile may be established along a
subsequent portion of
the flow path. The second or subsequent temperature profile may have a
positive, neutral or
negative temperature gradient. Where it has a negative gradient, it may be
smaller than the first
temperature profile. Alternatively, the second or subsequent temperature
profile may have a
negative gradient which is greater than the first temperature profile. The
second or subsequent
temperature profile may extend for the remainder of the flow path to the air
outlet.
In line with the above aspect, there is also envisaged an aerosol generating
component
for use with an electrically operated non-combustible aerosol delivery system,
wherein the
aerosol generating component defines a longitudinal-axis and is configured to
be heated
heterogeneously along its longitudinal axis. For example, during activation of
the aerosol
44
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
generating component a first temperature profile with a negative gradient is
established along a
portion of the longitudinal axis of the aerosol generating component. The
negative gradient may
be established along less than 50%, less than 20%, less than 15%, less than
10% or less than
5% of its longitudinal axis. Heterogeneous heating may be imparted to the
aerosol generating
component as described above, e.g. by varying the feeding of aerosolisable
material to portions
of the aerosol generating component, or by altering the flow of current
through
upstream/downstream portions/segments of the aerosol generating component as
described
above.
Due to the upstream/downstream configuration of the above mentioned portions
135 to
139, it is clear that the impact on temperature within the aerosol generating
chamber will also
take a corresponding upstream/downstream configuration. However, as described
above in
connection with the broader disclosure, the aerosol generating component may
be one having
portions of greater and lesser rates of vaporisation configured in other ways
which generally
result in a lateral temperature gradient being established. Any of the
embodiments described
above with respect to the modulation of rates of vaporisation of the aerosol
generating
component may be employed in the context of the present aspect.
The articles described herein may further comprise a mouthpiece which is in
fluid
communication with the one or more air outlets of the aerosol generating
chamber.
The articles described herein may comprise an outer housing within which the
aerosol
generating chamber and aerosol generating component are located. However, it
may be that
the article is composed of just the aerosol generating chamber and aerosol
generating
component. Where such an outer housing is present, it may further accommodate
the store for
aerosolisable material mentioned above. Such a housing may also accommodate
the
mouthpiece and any connectors required to ensure connection with an
electrically operated
aerosol delivery device (discussed further below). The outer housing may
surround the aerosol
generating chamber so as to form the above mentioned store for aerosolisable
material.
The articles described herein are typically for use with an electrically
operated aerosol
delivery system. For example, the electrically operated aerosol delivery
system may comprise
the article described herein and an electrically operated aerosol delivery
device. The article and
the device may be connected so as to form the electrically operated aerosol
delivery system. In
this regard, the electrically operated aerosol delivery device generally
comprises a power
source and a controller. Both the article and the electrically operated
delivery device may
comprise electrical connectors which mate with each other so as to facilitate
current flow to the
article. Alternatively, the device may include an inductor coil which is used
to generate an
CA 03172016 2022- 9- 15
WO 2021/198656
PCT/GB2021/050755
alternating magnetic field which can be used to induce electrical current flow
within the aerosol
generating component of the article. The controller of the device operates to
direct power from
the power source to the article when instructed to do so by a user. For
example, the device
may include some form of user interface, e.g. a touch sensor, button or the
like, which may be
operated by the user when an aerosol is to be generated. Alternatively, or
additionally, the
controller may receive a signal from one or more sensors (located either on
the device or
article) following the detection that an aerosol is to be produced. In
response to such a signal,
the controller operates to direct power from the power source to the article.
Such sensors
include air flow sensors, pressure sensors etc.
Upon connection of the article and the electrically operated aerosol delivery
device, an
airflow path may be created which facilitates the passage of air from the
external environment to
the one or more air inlets described herein, through the aerosol generating
chamber, through
the one or more air outlets and through a mouthpiece of the article.
The various embodiments described herein are presented only to assist in
understanding and teaching the claimed features. These embodiments are
provided as a
representative sample of embodiments only, and are not exhaustive and/or
exclusive. It is to be
understood that advantages, embodiments, examples, functions, features,
structures, and/or
other aspects described herein are not to be considered limitations on the
scope of the
invention as defined by the claims or limitations on equivalents to the
claims, and that other
embodiments may be utilised and modifications may be made without departing
from the scope
of the claimed invention. Various embodiments of the invention may suitably
comprise, consist
of, or consist essentially of, appropriate combinations of the disclosed
elements, components,
features, parts, steps, means, etc., other than those specifically described
herein. In addition,
this disclosure may include other inventions not presently claimed, but which
may be claimed in
future.
46
CA 03172016 2022- 9- 15
