Note: Descriptions are shown in the official language in which they were submitted.
CA 02722682 2010-10-26
1
DESCRIPTION
SMOKING ARTICLE
Technical Field
The present invention relates to a smoking
article, especially a smoking article comprising a
filter containing a flavor component.
Background Art
A smoking article, for example, a cigarette, is
composed of various materials, such as tobacco shreds,
paper, a filter, and activated carbon occasionally
filled in the filter. Further, the cigarette and other
smoking articles are loaded with various flavor
components to create the taste and aroma peculiar to
each cigarette product. In recent years, in order to
offer a broader spectrum of flavor, it has been the
practice to incorporate a flavor component in the
filter attached to the cigarette so that the flavor
exhibited by the cigarette per se can be altered or
reinforced.
Heretofore, there have been employed a method in
which a flavor component is directly incorporated in a
filter, and a method in which a flavor component is
adsorbed on porous particles, such as activate carbon,
and the resultant porous particles are added to a
filter, and the like, as a method for incorporating a
CA 02722682 2010-10-26
2
flavor component in a cigarette filter. However, it is
likely for the cigarette with a filter having a flavor
component directly incorporated therein to be unable to
ensure stable flavoring because of the migration of the
flavor component from the filter section to another
tobacco material section due to the adsorption
equilibrium within the package through the distribution
stage of the cigarette product. The cigarette with a
filter containing porous particles having a flavor
component adsorbed thereon cannot attain satisfactory
release of the flavor component because of the
incomplete desorption of the flavor component from the
porous particles at the time of smoking.
Moreover, for example, Jpn. Pat. Appin. KOKAI
Publication No. H4-75578 and Jpn. UM Appin. KOKOKU
Publication No. H5-45198 disclose cigarettes of such a
type that a filter is loaded with particles wherein a
flavoring material is covered with a natural
polysaccharide and at the time of smoking, the
particles are collapsed to thereby release the flavor
component. Further, Jpn. Pat. Appin. KOKAI Publication
No. H10-279986 discloses a cigarette with a filter
loaded with a flavor component-including cyclodextrin.
Still further, Jpn. UM Appin. KOKOKU Publication
No. S48-40719 discloses a filter loaded with a
flavoring material capsule in which the covering is
made of polyvinyl alcohol or the like. However, none
, CA 02722682 2010-10-26
3
of these cigarettes can ensure stable retention of a
flavor component during the non-smoking period but
immediate release of the flavor component at the time
of smoking.
Disclosure of Invention
Therefore, it is an object of the present
invention to provide a smoking article that can ensure
stable retention of a flavor component but immediate
release of the flavor component at the time of smoking.
In order to stably retain a flavor component in a
filter during the non-smoking period, it is preferred
to fix the flavor component in the filter. To this
end, it would be best to incorporate the flavor
component in an appropriate matrix material.
Additionally, taking into account the efficient release
of the flavor component at the time of smoking, it is
preferred for the matrix material to be one not only
easily soluble in the moisture contained in the aerosol
generated during smoking but also having a large
surface area for contact with the aerosol. Therefore,
it is preferred to incorporate the flavor component in
a water-soluble matrix with a particle diameter as
small as possible. Taking this knowledge into account,
the inventors have conducted extensive and intensive
studies. As a result, they found that the intended
object can be attained by incorporating the flavor
component in water-soluble matrix particles having
CA 02722682 2012-07-10
4
particle diameters ranging from 1 to 100 pm and having
an average particle diameter of 20 pm or less.
Thus, according to the present invention, there is
provided a smoking article comprising an aerosol-generating
section and a filter section attached to the aerosol-
generating section, the filter section containing a plurality
of flavor-releasing particles each containing a water-soluble
matrix containing a flavor component, the plurality of flavor-
releasing particles having respective particle diameters
ranging from 1 to 100 pm and having an average particle
diameter of 20 pm or less, wherein with respect to the flavor-
releasing particles, the number of particles each having a
diameter from 1 pm to 50 pm accounts for 90% or more of a
total number of particles.
Brief Description of Drawings
FIG. 1 is a schematic sectional view illustrating
one form of combustion-type smoking article according
to the present invention.
FIG. 2 is a schematic sectional view illustrating
another form of combustion-type smoking article
according to the present invention.
FIG. 3 is a schematic sectional view illustrating
one form of non-combustion-type smoking article
according to the present invention.
FIG. 4 is a schematic sectional view illustrating
CA 02722682 2012-07-10
4a
a further form of combustion-type smoking article
according to the present invention.
FIG. 5 is a schematic sectional view illustrating
still a further form of combustion-type smoking article
CA 02722682 2010-10-26
5
according to the present invention.
FIG. 6 is a schematic sectional view illustrating
yet still a further form of combustion-type smoking
article according to the present invention.
FIG. 7 is a graph illustrating the particle size
distribution of flavor-releasing particles according to
the present invention.
Best Mode for Carrying Out the Invention
A smoking article according to the present
invention has a filter containing a plurality of
flavor-releasing particles fitted to one end of an
aerosol-generating section.
Each of the flavor-releasing particles comprises a
water-soluble matrix containing a flavor component.
Each flavor-releasing particle has a particle diameter
ranging from 1 to 100 pm, preferably 1 to 50 pm, and
the plurality of flavor-releasing particles contained
in the filter have an average particle diameter of
pm or less, preferably 10 pm or less. Especially
20 preferred flavor-releasing particles each have a
particle diameter ranging from 1 to 50 pm and have an
average particle diameter of 10 pm or less, usually 1
to 10 pm. In the present invention, both the particle
diameter and average particle diameter are those
measured by a laser diffraction/scattering method. The
average particle diameter refers to a volume average
diameter. The flavor-releasing particles according to
CA 02722682 2010-10-26
6
the present invention have a narrow particle size
distribution. The number of particles each having a
diameter greater than zero but not exceeding 50 pm can
account for 90% or more of the total number of
particles. Preferably, the number of particles each
having a diameter greater than zero but not exceeding
30 pm can account for 80% or more of the total number
of particles.
The water-soluble matrix in which the flavor
component is contained (incorporated) is not
particularly limited as long as after the incorporation
of the flavor component, the flavor component is not
released during the non-smoking period (including the
period of keeping and storage) of the smoking article.
As the material of the matrix, use can be made of a
water-soluble polymer, for example, dextrin, gelatin,
gum arabic, polyvinyl alcohol, carboxymethylcellulose
or the like. Dextrin is most preferred because of its
high solubility in water. Dextrin can be dissolved in
water in an amount of SO% by weight or more.
The flavor component for use in the present
invention is not particularly limited as long as it
satisfies the human palate through the taste and smell.
Both hydrophobic and hydrophilic flavor components can
be used. As examples of the hydrophobic flavor
components, there can be mentioned menthol, esters (for
example, isoamyl acetate, linalyl acetate, isoamyl
CA 02722682 2010-10-26
7
propionate, linalyl butyrate and the like), natural
essential oils (plant essential oils, such as a vanilla
extract, spearmint, peppermint, cassia and jasmine, and
animal essential oils, such as musk, amber, civet and
castor) and simple flavoring materials (for example,
anethole, limonene, linalool, eugenol and the like).
As examples of the hydrophilic flavor components, there
can be mentioned a leaf tobacco extract, natural plant
flavoring materials (for example, licorice, St. John's
bread, a plum extract, a peach extract and the like),
acids (for example, malic acid, tartaric acid, citric
acid and the like), sugars (for example, glucose,
fructose, isomerized sugar and the like) and polyhydric
alcohols (propylene glycol, glycerol, sorbitol and the
like). These components can be used singly or in
combination.
The configuration of the flavor-releasing
particles is not particularly limited. However, being
spherical is especially preferred.
In the present invention, especially preferred
flavor-releasing particles are microparticles having
particle diameters ranging from 1 to 50 pm and having
an average particle diameter of 10 pm or less, usually
1 to 10 pm. Thus, the particles can be appropriately
produced by means of a special spray dryer of a four-
fluid nozzle spray type (Micromist dryer MDL-050M
manufactured by Fujisaki Electric Co., Ltd.). The
CA 02722682 2010-10-26
8
particles that can be produced by conventional spray
dryers generally sold on the market have diameters
whose average generally exceeds 30 pm, and the particle
size distribution thereof is also broad.
In the production of flavor-releasing particles in
which a hydrophobic flavor component has been
incorporated, an emulsifying agent is used to emulsify
the hydrophobic flavor component. The type of
emulsifying agent is not limited. For example, use can
be made of a sucrose fatty acid ester, a polyglycerol
fatty acid ester, a glycerol fatty acid ester, a
sorbitan fatty acid ester, lecithin or the like. Of
the mentioned emulsifying agents, a sucrose fatty acid
ester is especially preferred.
In the production of flavor-releasing particles
containing a hydrophobic flavor component, first, a
requisite amount of emulsifying agent is added to water
and agitated at a temperature higher than the melting
point of the emulsifying agent (for example, 50 to
60 C), thereby dissolving the emulsifying agent.
Thereafter, a water-soluble matrix material (water-
soluble polymer) is added and dissolved therein.
Further, a hydrophobic flavor component is added and
emulsified at 50 to 60 C by means of a homogenizing
mixer so that the average particle diameter of the
emulsion becomes 2 pm or less, preferably 0.5 pm or
less. The resultant emulsion is spray dried (120 to
CA 02722682 2010-10-26
9
200 C) by means of the above micromist dryer. Thus,
desired flavor-releasing particles can be obtained.
In the production of flavor-releasing particles
containing a hydrophilic flavor component, it is not
needed to add an emulsifying agent. The production can
be accomplished by adding a hydrophilic flavor
component to an aqueous solution of a water-soluble
matrix material (water-soluble polymer), agitating the
mixture to thereby obtain a solution, and spray drying
the solution (120 to 200 C) by means of the above
micromist dryer.
It is preferred for the amount of each of the
components of the flavor-releasing particles to be as
follows. The amount of water-soluble matrix material
is in the range of 40 to 95% by weight, especially 70
to 90% by weight. The amount of emulsifying agent is
in the range of 0.5 to 5% by weight, especially 1 to 2%
by weight. The amount of flavor component is in the
range of trace to SO% by weight, especially 10 to 30%
by weight. One type or two or more types of flavor-
releasing particles can be added to a filter.
It has been ascertained that even when the flavor-
releasing particles according to the present invention
are stored for a prolonged period of time under the
conditions of 55 C and 35% relative humidity or 22 C
and 60% relative humidity, no release of the flavor
component is found, exhibiting an extremely high
CA 02722682 2010-10-26
10
retention stability, while the flavor component is
released only after the particles are placed under
high-humidity conditions of 22 C and 75% relative
humidity.
The flavor-releasing particles are contained in a
filter section. The material for constructing the
filter is not particularly limited as long as the
material can be applied to ordinary smoking. As
examples of the filter materials, there can be
mentioned, for example, cellulose acetate, paper, a
non-woven sheet of natural pulp (filter fabricated by
rolling this sheet into a rod form is commercially
available from Japan Filter Technology, Ltd., under the
trade name of Neo Filter), polypropylene and rayon.
In the smoking article of the present invention,
the configuration of the filter section is not
particularly limited as long as a filter containing the
flavor-releasing particles according to the present
invention is included therein. The filter section can
include a charcoal filter. The charcoal filter is
preferably disposed upstream of the filter containing
the flavor-releasing particles according to the present
invention in the direction of smoking in order to avoid
the adsorption of flavor released at the time of
smoking on charcoal. As examples of the structures of
the filter sections, there can be mentioned a plain
structure (only a filter containing the
CA 02722682 2010-10-26
11
flavor-releasing particles according to the present
invention), a dual structure (for example, a
combination of a filter containing the flavor-releasing
particles according to the present invention and a
cellulose acetate filter, a combination of a charcoal
filter and a filter containing the flavor-releasing
particles according to the present invention, or the
like), a triple filter (for example, a combination of a
charcoal filter, a filter containing the flavor-
releasing particles according to the present invention
and a cellulose acetate filter, or the like), a
multisegment structure (for example, a combination of a
cellulose acetate filter, a charcoal filter, a filter
containing the flavor-releasing particles according to
the present invention and a cellulose acetate filter,
or the like), a recess filter (for example, a cavity
portion provided at a mouthpiece portion in each of
these filter structures), a core-sheath dual concentric
filter, a CVD (channel ventilation dam) filter, a
thermoformed filter such as a filter provided at its
central area with a hole (for example, a conical hole),
and the like.
The smoking articles of the present invention
include a combustion-type smoking article configured
to, like usual cigarettes, generate an aerosol when
combusted to thereby permit flavor tasting, and a non-
combustion-type smoking article configured to generate
CA 02722682 2010-10-26
12
an aerosol by heating, involving substantially no
combustion of smoking material. The non-combustion-
type smoking article generally comprises an aerosol-
generating section containing an aerosol-generating
substance capable of generating an aerosol when heated,
and a heating source disposed at the distal end of the
aerosol-generating section and separated physically
from the aerosol-generating section, the heating source
capable of heating the aerosol-generating substance by
the heat of combustion. The expression "separated
physically" means that the aerosol-generating section
and the heat source are disposed as physically separate
items (separate bodies).
The aerosol-generating section of the combustion-
type smoking article contains a usual combustible
smoking material, such as tobacco shreds. That is, the
combustion-type smoking article of the present
invention can have the same structure as that of usual
cigarettes except that the filter section includes a
filter containing the flavor-releasing particles
according to the present invention.
The aerosol-generating section of the non-
combustion-type smoking article contains an aerosol-
generating substance capable of generating an aerosol
when heated. As the aerosol-generating substance, use
can be made of, for example, a polyhydric alcohol, such
as glycerol, propylene glycol, triethylene glycol or
CA 02722682 2010-10-26
13
tetraethylene glycol, or an aliphatic ester of
carboxylic acid, such as methyl stearate, dimethyl
dodecanedioate or dimethyl tetradecanedioate. The
aerosol-generating substance is usually supported on an
appropriate carrier, thereby providing an aerosol-
generating member. A porous material, such as paper or
activated carbon, can be used as the carrier. The
aerosol-generating substance is absorbed into or
adsorbed on the porous material. Alternatively, a
glucan gel, such as curdlan, described in the
specification of Japanese Patent No. 3,118,462 can be
used as the carrier. Specifically, an aerosol-
generating substance is added to an aqueous dispersion
of heat-irreversibly coagulating glucan, and the
resultant dispersion is cast in the form of a thin-film
sheet on a support (for example, a stainless steel
belt). Thereafter, the cast sheet is dried by heating
to thereby gel the glucan. The thus obtained glucan
gel holding the aerosol-generating substance can be
shredded or pulverized for use. The carrier carrying
the aerosol-generating substance (aerosol-generating
member) can be accommodated in a cylindrical body
formed of a nonflammable/heat insulating material, such
as a paper sheet containing glass fibers, a ceramic or
a paper sheet lined with a metal foil, thereby
providing the aerosol-generating section. The
heating source fitted to the distal end of the
CA 02722682 2010-10-26
14
aerosol-generating section generally comprises a
carbonaceous material.
Now, the present invention will be described with
reference to the appended drawings. Through the
drawings, the same reference numerals are used to
denote the same elements, and any further repetitive
descriptions of the same elements will be omitted.
FIG. 1 illustrates one form of smoking article of
the present invention having the configuration of usual
cigarettes. The illustrated smoking article
(cigarette) 10 comprises a cylindrical aerosol-
generating member (for example, tobacco shreds) 111
formed of a combustible smoking material (for example,
tobacco shreds) usable for smoking, the circumference
of which is wrapped with a wrapping paper 112, thereby
constructing an aerosol-generating section 11. A
filter section 12 is fitted to one end of the aerosol-
generating section 11. In the cigarette of FIG. 1, the
filter section 12 comprises a filter composed of a
cylindrical filter material 121 with the same diameter
as that of the aerosol-generating section 11 and a
wrapping paper 122 enclosing the circumference thereof.
The filter material 121 is loaded with dispersed
flavor-releasing particles 123 according to the present
invention. The aerosol-generating section 11 and the
filter section 12 are joined together by means of a
tipping paper 101. The tipping paper 101 can be
CA 02722682 2010-10-26
15
provided with ventilation holes 101a in the same
fashion as in usual cigarettes. The distal end of the
aerosol-generating section 11 is ignited, and the
aerosol-generating member is combusted, so that smoke
can be drawn at the filter section 12. Smoke particles
are brought into contact with the flavor-releasing
particles incorporated in the filter section, and the
flavor-releasing particles are dissolved and
disintegrated by the moisture contained in the smoke
particles, thereby releasing flavor. Thus, the flavor
can be tasted.
FIG. 2 illustrates one form of smoking article of
the present invention having the configuration of usual
cigarettes which includes, in addition to a filter
containing the flavor-releasing particles according to
the present invention, a charcoal filter. The
illustrated smoking article (cigarette) 20 comprises an
aerosol-generating section 11 and, attached to one end
thereof, a filter section 21 composed of a charcoal
filter 13 and a filter 12 containing the flavor-
releasing particles according to the present invention.
The charcoal filter 13 is composed of a cylindrical
filter material 131 and a wrapping paper 132 enclosing
the circumference thereof. In the filter material 131,
charcoal (activated carbon) particles not illustrated
are dispersed. Alternatively, the charcoal filter 13
may be one in which the space to be filled with the
CA 02722682 2010-10-26
16
filter material 131 is left as it is as a cavity and
activated carbon particles are filled therein. The
filter 12 and the filter 13 are integrated together by
means of a wrapping paper not illustrated. The filter
section 21 is joined to the aerosol-generating section
11 by means of a tipping paper 101 which may be
provided with ventilation holes. The charcoal filter
13 is disposed upstream of the filter 12 containing the
flavor-releasing particles according to the present
invention in the direction of smoking, so that the
flavor released from the flavor-releasing particles
according to the present invention are substantially
not adsorbed by the charcoal filter 13.
FIG. 3 illustrates one form of non-combustion-type
smoking article according to the present invention.
The illustrated non-combustion-type smoking article 30
includes a heat insulating cylindrical body 31, the
interior of which is partitioned into four sections.
In the first section disposed on the distal-end side of
the cylindrical body 31, for example, a columnar
carbonaceous heat source 32 provided on its
circumference with a plurality of grooves (not
illustrated) along the longitudinal direction thereof
is inserted in the form of being accommodated in a heat
insulating cylindrical body 33 formed of, for example,
glass fibers. The second section succeeding the first
section is filled with an aerosol-generating member 34
CA 02722682 2010-10-26
17
capable of generating an aerosol when heated. Tobacco
shreds 35 can be accommodated in the third section
succeeding the second section. The interior of the
fourth section succeeding the third section is filled
with a filter material 36 loaded with dispersed flavor-
releasing particles 37 according to the present
invention. The circumference of the cylindrical body
31 can further be covered with a paper material 38. In
this non-combustion-type smoking article, a charcoal
filter (not illustrated) can be disposed between the
third section and the fourth section.
When the carbonaceous heat source 32 is ignited
and a draught from the smoking article is taken, air is
drawn through the grooves disposed on the circumference
of the carbonaceous heat source 32, thereby heating the
aerosol-generating members 34, 35 and thus generating
an aerosol (smoke particles). The generated smoke
particles are brought into contact with the flavor-
releasing particles 37 incorporated in the filter
material 36, so that the flavor-component holding
material is dissolved and disintegrated by the moisture
contained in the smoke particles, thereby releasing
flavor.
FIG. 4 illustrates one form of combustion-type
smoking article (cigarette) with a dual concentric
filter. The illustrated cigarette 40 has a dual
concentric filter 41 attached to the posterior end of
CA 02722682 2010-10-26
18
the filter 12 of the cigarette illustrated in FIG. 1.
The dual concentric filter 41 comprises a core portion
42 through which smoke passes and a sheath portion 43
enclosing the core portion 42. The core portion 42 is
composed of a filter material 421 loaded with dispersed
flavor-releasing particles 422 according to the present
invention. The dual concentric filter 41 is wrapped
with a wrapping paper 411. The sheath portion 43 is
formed of a filter material 431. The filters 12 and 41
are integrated together by means of a wrapping paper
not illustrated, and joined to an aerosol-generating
section 11 by means of a tipping paper 101. The
tipping paper 101 is provided with a plurality of
ventilation holes 101a at a position corresponding to
an area including the boundary of the filters 12 and
41. Outside air (diluent air) introduced thorough the
ventilation holes 101a flows through the sheath portion
43 while smoke flows through the core portion.
FIG. 5 illustrates another form of combustion-type
smoking article (cigarette) with a dual concentric
filter. In the illustrated cigarette 50, a dual
concentric filter 41 having a structure different from
that of the dual concentric filter 51 of FIG. 4 is
attached to the posterior end of the filter 12 of the
cigarette illustrated in FIG. 1. The dual concentric
filter 51 comprises a core portion 52 through which
smoke passes and a sheath portion 53 enclosing the core
CA 02722682 2010-10-26
19
portion 52. The core portion 52 is formed of a filter
material 521. The sheath portion 53 is composed of a
filter material 531 loaded with dispersed flavor-
releasing particles 532 according to the present
invention. The dual concentric filter 51 is wrapped
with a wrapping paper 511. The filters 12 and 51 are
integrated together by means of a wrapping paper not
illustrated, and joined to an aerosol-generating
section 11 by means of a tipping paper 101. The
tipping paper 101 is provided with a plurality of
ventilation holes 101a at a position corresponding to
an area including the boundary of the filters 12 and
41. Each of the ventilation holes runs through the
tipping paper 101, wrapping paper not illustrated and
wrapping papers 122, 511 and reaches the core portion
52. Outside air (diluent air) introduced thorough the
ventilation holes 101a flows through the core portion
52 while smoke flows through the sheath portion 53.
FIG. 6 illustrates one form of smoking article
(cigarette) with a multisegment filter section
including a dual concentric filter. The illustrated
cigarette 60 includes an aerosol-generating section 11
in the same fashion as in the cigarette of FIG. 1. The
same charcoal filter 13 as illustrated in FIG. 2, the
same filter 12 containing the flavor-releasing
particles 123 according to the present invention as in
FIG. 1, the same dual concentric filter 41 as
CA 02722682 2010-10-26
20
illustrated in FIG. 4 and a usual filter 61 comprising
a filter material 611 wrapped in a wrapping paper 612
are in this order fitted to one end of the aerosol-
generating section 11. These four filters 13, 12, 41
and 61 are integrated together by means of a wrapping
paper not illustrated, and joined to the aerosol-
generating section 11 by means of a tipping paper 101.
The tipping paper 101 is provided with a plurality of
ventilation holes 101a at a position corresponding to
an area including the boundary of the filters 12 and
41. Outside air (diluent air) introduced thorough the
ventilation holes 101a flows through the sheath portion
43 of the filter 41 while smoke flows through the core
portion 42 and is drawn through the filter 61 into the
smoker's mouth.
The flavor-component holding material employed in
the smoking article of the present invention exhibits
the following characteristics. The particle diameter
thereof is small, so that the area of contact with
smoke particles is large. Further, the matrix material
forming the flavor-releasing particles has a high
solubility in water, so that not only can appropriate
flavor release occur from the initial puff but also a
high ratio of flavor release (12% or higher in the
ratio of the migration of flavor component into smoke)
can be attained.
The present invention will be described by way of
CA 02722682 2010-10-26
21
its Examples. However, the present invention is in no
way limited to these Examples.
Example 1
Sucrose fatty acid ester (HLB value: 11) as an
emulsifying agent was added in an amount of 0.5 parts
by weight to 59.5 parts by weight of purified water,
and agitated at about 60 C for 10 minutes to thereby
dissolve the ester in the water. Thereafter, 40.0
parts by weight of dextrin (dextrose equivalent value:
18) was added to the solution and dissolved therein.
The temperature of the thus obtained solution was
adjusted to 50 to 60 C, and 10.125 parts by weight of
menthol was added to the solution and dissolved
therein. Emulsification of the solution was carried
out by means of a TK HOMO Mixer at 12,000 rpm for
10 minutes, thereby obtaining a spray liquid. The
spray liquid consisted of an emulsion of 0.2 pm
particle diameter. This spray liquid while maintaining
its temperature at 50 to 60 C was fed to a spray dryer
(spray dryer MDL-050M manufactured by Fujisaki Electric
Co., Ltd.), and spray dried at 180 C, thereby obtaining
desired flavor-releasing particles. The particle size
distribution of these flavor-releasing particles was
determined by means of a laser diffraction/scattering
particle size distribution measuring apparatus (LA-920
manufactured by Horiba, Ltd.) (ethanol used as a
particle dispersion medium). The results are given in
CA 02722682 2010-10-26
22
FIG. 7. As apparent from FIG. 7, the particles
produced by means of the four-fluid nozzle spray dryer
have small diameters (particle diameters ranging from
1.151 to 44.938 pm), and the particle size distribution
thereof is also very narrow. The volume average
diameter of the obtained flavor-releas.ing particles was
9.2879 pm (median diameter: 8.2563 pm). It was found
by an analysis that the obtained flavor-releasing
particles consisted of 79% by weight of dextrin, 1% by
weight of sucrose fatty acid ester and 20% by weight of
menthol.
The above flavor-releasing particles were stored
for three months under each of the condition of 55 C
and 35% relative humidity and the condition of 22 C and
60% relative humidity, thereby studying the storage
stability thereof. As a result, no release of menthol
from the flavor-releasing particles was found under
both the storage conditions, thereby attesting to an
extremely high flavor retention stability. When the
flavor-releasing particles were stored under the
condition of 22 C and 75% relative humidity, for the
first time, the release of menthol was found.
Further, a cellulose acetate filter of 2.8Y35000
and 18 mm length was loaded with 26 mg (amount of
menthol: 6.3 mg) of these flavor-releasing particles in
dispersed form, and fitted to the tobacco column
portion of commercially available Mild Seven Super
CA 02722682 2010-10-26
23
Light by means of a tipping paper. The tipping paper
was provided with ventilation holes allowing the
dilution ratio of mainstream smoke to be 40%. The thus
obtained cigarette was smoked under the standard
smoking conditions prescribed in ISO. The release of
menthol concurrent with smoking was found, exhibiting
the same puff pattern as that of usual menthol
cigarette products. The tar quantity was
7.1 mg/cigarette, and the nicotine quantity was
0.5 mg/cigarette. The amount of menthol released was
0.78 mg/cigarette, and the ratio of menthol migrated
into smoke was 12.4%. The amount of menthol released
was equivalent to or superior to that exhibited by
usual menthol cigarettes with substantially the same
tar value (0.4 to 0.6 mg/cigarette).
As described above, the smoking article of the
present invention can stably retain a flavor component
and, at the time of smoking, can immediately release
the flavor component.
