Note: Descriptions are shown in the official language in which they were submitted.
SILVER NANOPARTICLE FUNCTIONALIZED FACE MASK
AND INSERT FOR A FACE MASK
FIELD
The present technology is directed to a face mask or mask insert for a mask
that can be
worn by a user to protect them from airborne microbes, including bacteria,
fungus and
viruses. More specifically, it is a face mask or mask insert that traps the
microbes and
kills a substantial percentage of them on contact.
BACKGROUND
It is well known that filters need to have a 0.2 micrometer (micron) pore size
or smaller to
sterilize liquids and gases. Despite this, disposable masks for protecting
against disease
have much larger pore sizes. For example, the N95 mask, which is promoted as
the
mask of choice for the general public to wear, has a pore diameter of 0.3
microns. As the
name suggests, the mask is supposed to remove 95% of particulate matter that
is 0.3
microns or larger in diameter. Unfortunately, many bacteria are smaller than
0.3 microns.
For example, Haemophilus influenzae ranges in diameter from about 0.2 microns
to about
0.3 microns. Viruses are generally smaller than bacteria and may range is
diameter from
30 nanometers (0.03 microns) for the polio virus to 120-150 nanometers (0.120-
0.150
microns) for the HIV-1 virus. The COVID-19 virus is reported to range in
diameter
between about 0.06 microns to about 0.14 microns. Based on the foregoing, it
is apparent
that the N95 mask is insufficient to protect a user from some bacteria and
most viruses,
both of which are the most common pathogens.
Another problem with the disposable masks is contamination. Even if the mask
can
reduce the passage of pathogens from the ambient to the user, the mask is then
contaminated. If the mask is not properly disposed of or is reused, it then
becomes a
source of infection.
Yet another problem with disposable masks is air flow. As the pore size
restricts air flow,
these masks are not suitable for users with breathing issues, such as
decreased lung
capacity and shortness of breath. In one study, breathing through N95 mask
materials
have been shown to impede gaseous exchange and impose an additional workload
on
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the metabolic system. Specifically, N95-mask materials reduced mean tidal
volume by
23.0 % (95 A CI -33.5 A to -10.5 %, p< 0.001) and lowered minute ventilation
by
25.8 % (95 A CI -34.2 A to -15.8 A, p< 0.001), with no significant change
in breathing
frequency compared to breathing ambient air. Volumes of oxygen consumption
(V02) and
carbon dioxide expired (VCO2) were also significantly reduced; V02 by 13.8 %
(95 % CI
-24.2% to -3 %, p = 0.013) and VCO2 by 17.7%, (95% CI -28.1 % to
-8.6 A, p= 0.001).
As disclosed in US Patent No. 8,815,131 "Although a hybrid nanostructure in
which a
silver nanoparticle is bound to a carbon nanotube is disclosed in the prior
art (Korean
Patent Publication No. 2011-78136), since the silver nanoparticle is not
dissolved in a
solvent, the binding efficiency of the silver nanoparticle to the carbon
nanotube is very
poor when a hybrid nanostructure is formed by dispersing the silver
nanoparticle and the
carbon nanotube in a solvent according to the method of the present
disclosure."
Chinese Patent Application No. 111617563 discloses a degerming antibacterial
graphene
filter element for a vehicle-mounted air conditioner, which belongs to the
field of air
filtration and is characterized by comprising a supporting seat, a fixing
layer and a plurality
of sleeve pipe assemblies, wherein the supporting seat comprises a first
support and a
second support; the sleeve assembly comprises a first filtering sleeve, a
second filtering
sleeve and a third filtering sleeve, wherein the first filtering sleeve is
composed of a first
non-woven fabric layer, an activated carbon filtering layer and a first non-
woven fabric
layer which are sequentially arranged, the activated carbon layer is clamped
between the
two first non-woven fabric layers, the second filtering sleeve is sleeved
outside the first
filtering pipe and is composed of a second non-woven fabric layer, a graphene
silver
nanoparticle filtering layer and a second non-woven fabric layer which are
sequentially
arranged, and the graphene silver nanoparticle filtering layer is clamped
between the two
second non-woven fabric layers; aims to solve the problems that the filter
element of the
vehicle-mounted air conditioner filter has short service life, needs to be
replaced
frequently, is inconvenient to replace and operate and the like.
Chinese Patent No. 103738944 discloses a method to prepare nanoparticle doped
three-
dimensional graphene. Technical solution of the present invention includes:
make
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Date Recue/Date Received 2021-01-18
graphene oxide lamella using graphite as stock, by nanoparticle appendix on
graphene
oxide lamella, and by being self-assembly of three-dimensional graphene
between the
rare lamella of graphite. By regulating reaction temperature and graphene
oxide solution
concentration, the three-dimensional graphene of perforate, closed pore
(different
densities) is provided. The three-dimensional graphene prepared by the present
invention can be widely used in the fields such as ultracapacitor, oil
suction,
desalinization.
United States Patent Application Publication No. 20200376305 discloses
personal
protection systems against COVID-19 including face masks and methods, systems
or
devices of managing, regulating and/or filtering airflow during travel on an
aircraft, train,
or bus. A mesh of nonwoven polypropylene fabric with silver nanoparticles is
disclosed.
United States Patent Application Publication No. 20160113336 discloses a mask
has a
mask body and a pair of ear straps. The mask body includes an outer layer
sheet and an
intermediate layer sheet. The outer layer sheet is formed of hydrophobic
fibers. The
intermediate layer sheet is laid on the outer layer sheet so as to be located
on a wearer's
side of the outer layer sheet when the mask is worn. The intermediate layer
sheet includes
a first fiber layer which is formed of polyolefin fibers, which may be non-
woven
polypropylene, containing an inorganic antimicrobial agent, which may be
silver ions and
a second fiber layer which is formed of polyolefin fibers and has a larger
fiber diameter
than the first fiber layer. The fiber diameter of the first fiber layer is
within a range of 0.5
to 2.8 p and the ratio of a particle diameter of the inorganic antimicrobial
agent with
respect to the fiber diameter is within the range of 0.1 to 6Ø
What is needed is a face mask or mask insert that kills a substantial
percentage of
airborne microbes on contact and additionally traps the microbes, while
minimally
restricting air flow to the user. It would be preferable if it was inexpensive
to manufacture.
It would be further preferable if the face mask was form-fitting to a user's
face, covering
the chin, mouth and nostrils. It would be further preferable if the mask
insert could be
removed and replaced.
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Date Recue/Date Received 2021-01-18
SUMMARY
The present technology is a face mask or mask insert that kills a substantial
percentage
of airborne microbes on contact and additionally traps the microbes, while
minimally
restricting air flow to the user. It is inexpensive to manufacture. The face
mask is form-
fitting to a user's face, covering the chin, mouth and nostrils. The mask
insert can be
removed and replaced.
In one embodiment, a face mask is provided comprising a mask body, which
includes a
margin, and straps attached to the mask body proximate the margin for
releasably
retaining the mask on a user's face, the mask body including: an inner layer,
which is a
breathable material with interstitial spaces, and which has an inner surface
and an outer
surface; and a graphene layer which abuts the outer surface and is
functionalized with a
plurality of silver nanoparticles, to provide a functionalized graphene layer.
The face mask may further comprise an outer layer, which is breathable
material with
interstitial spaces and which has an inner surface and an outer surface, the
inner surface
abutting the functionalized graphene layer.
In the face mask, the breathable material may be non-woven polypropylene.
In the face mask, the breathable material may be a woven fabric.
In the face mask, the inner layer and the outer layer may define a pocket in
which the
functionalized graphene layer is releasably retained.
In another embodiment, an insert for a face mask is provided, the insert
comprising a
graphene layer which is functionalized with silver nanoparticles, the insert
shaped to be
inserted into a face mask.
In another embodiment, a method of reducing pathogens in air inhaled and
exhaled by a
user is provided, the method comprising providing a face mask comprising a
mask body,
which includes a margin, and straps attached to the mask body proximate the
margin for
releasably retaining the mask on a user's face, the mask body including: an
inner layer,
which is a breathable material with interstitial spaces, and which has an
inner surface and
an outer surface; and a graphene layer which abuts the outer surface and is
functionalized
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Date Recue/Date Received 2021-01-18
with a plurality of silver nanoparticles, to provide a functionalized graphene
layer; the user
locating the face mask on their face such that their mouth and nostrils are
covered; and
the user breathing through the face mask.
In another embodiment, a method of reducing pathogens in air inhaled and
exhaled by a
user is provided, the method comprising providing a face mask comprising a
mask body,
which includes a margin, and straps attached to the mask body proximate the
margin for
releasably retaining the mask on a user's face, the mask body including: an
inner layer,
which is a breathable material with interstitial spaces, and which has an
inner surface and
an outer surface; a graphene layer which abuts the outer surface and is
functionalized
with a plurality of silver nanoparticles, to provide a functionalized graphene
layer; and an
outer layer, which is breathable material with interstitial spaces and which
has an inner
surface and an outer surface, the inner surface abutting the functionalized
graphene
layer; the user locating the face mask on their face such that their mouth and
nostrils are
covered; and the user breathing through the face mask.
The method may further comprise the user removing the functionalized graphene
layer
and laundering a remainder of the face mask to provide a laundered remainder
of the
face mask.
The method may further comprise the user inserting a new functionalized
graphene layer
into the laundered remainder of the face mask.
The method may further comprise the user reinserting the functionalized
graphene layer
into the laundered remainder of the face mask.
FIGURES
Figure 1 is a face view of the mask of the present technology.
Figure 2 is a sectional view along lines A-A of Figure 1.
Figure 3 is a sectional view of an alternative embodiment.
Figure 4A is a sectional view of a mask with a mask insert; Figure 4B is a
face view of the
mask of Figure 4A.
Date Recue/Date Received 2021-01-18
Figure 5 is microscopic view of the functionalized graphene layer of the mask
and the
mask insert of the present technology.
DESCRIPTION
Except as otherwise expressly provided, the following rules of interpretation
apply to this
specification (written description and claims): (a) all words used herein
shall be construed
to be of such gender or number (singular or plural) as the circumstances
require; (b) the
singular terms "a", "an", and "the", as used in the specification and the
appended claims
include plural references unless the context clearly dictates otherwise; (c)
the antecedent
term "about" applied to a recited range or value denotes an approximation
within the
deviation in the range or value known or expected in the art from the
measurements
method; (d) the words "herein", "hereby", "hereof", "hereto", "hereinbefore",
and
"hereinafter", and words of similar import, refer to this specification in its
entirety and not
to any particular paragraph, claim or other subdivision, unless otherwise
specified; (e)
descriptive headings are for convenience only and shall not control or affect
the meaning
or construction of any part of the specification; and (f) "or" and "any" are
not exclusive
and "include" and "including" are not limiting. Further, the terms
"comprising," "having,"
"including," and "containing" are to be construed as open-ended terms (i.e.,
meaning
"including, but not limited to,") unless otherwise noted.
Recitation of ranges of values herein are merely intended to serve as a
shorthand method
of referring individually to each separate value falling within the range,
unless otherwise
indicated herein, and each separate value is incorporated into the
specification as if it
were individually recited herein. Where a specific range of values is
provided, it is
understood that each intervening value, to the tenth of the unit of the lower
limit unless
the context clearly dictates otherwise, between the upper and lower limit of
that range
and any other stated or intervening value in that stated range, is included
therein. All
smaller sub ranges are also included. The upper and lower limits of these
smaller ranges
are also included therein, subject to any specifically excluded limit in the
stated range.
Unless defined otherwise, all technical and scientific terms used herein have
the same
meaning as commonly understood by one of ordinary skill in the relevant art.
Although
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Date Recue/Date Received 2021-01-18
any methods and materials similar or equivalent to those described herein can
also be
used, the acceptable methods and materials are now described.
Definitions:
Pathogen ¨ in the context of the present technology, a pathogen is a living
microbe that
causes disease. Pathogens include but are not limited to a bacterium, a fungus
or a virus.
Aerosol ¨ in the context of the present technology an aerosol is a suspension
of solid
and/liquid particles in a gas.
Fluid ¨ in the context of the present technology, a fluid is a gas, a liquid
or both.
Airborne ¨ in the context of the present technology, airborne includes
aerosols and
particles in the air.
Silver nanoparticle ¨ in the context of the present technology, silver
nanoparticles are
particles that range in size from 1 nanometer to 100 nanometers in diameter.
The
nanoparticles include elemental silver and silver oxide.
Graphene ¨ in the context of the present technology, graphene is an allotrope
of carbon
consisting of a single layer of atoms arranged in a two-dimensional honeycomb
lattice.
Functionalized graphene ¨ in the context of the present technology,
functionalized
graphene is graphene with silver nanoparticles on at least a portion of the
surface of the
lattice.
Detailed Description:
A disposable face mask, generally referred to as 2 is shown in Figure 1. The
mask 2 has
a mask body 4, a margin 6, a nose piece 8 and two straps 10. The nose piece 8
is
formable and is preferably aluminum or a pliable plastic, which when molded on
a user's
nose retains its shape. The straps 10 are preferably elastomeric and are
retained on the
mask body 4 or margin 6. The mask body 4 is sufficiently resilient to maintain
its shape
when in use. It may be, as shown, cup-shaped.
As shown in Figure 2, the mask body 4 consists of two layers, an inner non-
woven
polypropylene layer 12 and an outer functionalized graphene layer 14. The
inner non-
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Date Recue/Date Received 2021-01-18
woven polypropylene layer 12 has interstitial spaces that allow for air flow
through the
mask body 4, hence it is breathable. An adhesive layer 16 is on the margin 6
to hold the
inner non-woven polypropylene layer 12 and the outer functionalized graphene
layer 14
in place, with the outer functionalized graphene layer abutting the outer
surface 15 of the
inner non-woven polypropylene layer 12.
In an alternative embodiment shown in Figure 3, the mask body 4 consists of
three layers,
an inner non-woven polypropylene layer 12, a middle, functionalized graphene
layer 14
and an outer non-woven polypropylene layer 18.
Both the inner non-woven
polypropylene layer 12 and the outer non-woven polypropylene layer 18 have
interstitial
spaces that allow for air flow through the mask body 10, hence they are
breathable. The
inner surface 20 of the outer non-woven polypropylene layer 18 abuts the
functionalized
graphene layer 14.
In an alternative embodiment shown in Figure 4A, a mask insert 30 is provided.
As shown
in Figure 4A, the mask insert 30 is retained between two layers of fabric, an
inner layer
32 and an outer layer 34, to form a reusable mask 36. Both layers are woven
fabric, for
example, cotton and have interstitial spaces that allow for air flow, hence
they are
breathable. The inner layer 32 and the outer layer 34 are stitched or glued or
otherwise
adhered to one another along most of an outer margin 38 to form a pocket 40
which has
an opening 42 to the ambient environment to allow for inserting and removing
the mask
insert 30. As shown in Figure 4B, the mask 36 is shaped to fit over the mouth,
chin and
at least the nostrils of the user's nose and is held in place with two straps
44 which may
fit over the user's ears. The mask insert 30 is a functionalized graphene
layer 14.
Returning to Figure 4A, the mask insert 30 abuts the outer surface 46 of the
inner layer
32 and an inner surface 48 of the outer layer 32 in the pocket 40.
As shown in Figure 5, the functionalized graphene layer 14 is one molecular
layer thick
and has hexagonal pores 24 created by a honeycomb lattice 26. Silver
nanoparticles 28
adhere to or are bound to or are associated with the surfaces of the lattice
26 and pores
24. The pores 24 allow for air flow.
The mask or mask insert is manufactured by dipping, spraying or otherwise
applying an
aqueous mixture of silver nanoparticles in water on the graphene layer which
has been
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cut to shape prior to wetting. The aqueous mixture is 10 ppm silver
nanoparticles. The
functionalized graphene layer is then allowed to dry and is pressed onto the
margins 6 of
the mask body 4 or is inserted into the pocket 40 of the reusable mask 36.
When the
reusable mask 36 is laundered, the mask insert 30 is removed and either
replaced with a
new mask insert 30 or the existing mask insert 30 is returned to the pocket
40.
While example embodiments have been described in connection with what is
presently
considered to be an example of a possible most practical and/or suitable
embodiment, it
is to be understood that the descriptions are not to be limited to the
disclosed
embodiments, but on the contrary, is intended to cover various modifications
and
equivalent arrangements included within the spirit and scope of the example
embodiment.
Those skilled in the art will recognize or be able to ascertain using no more
than routine
experimentation, many equivalents to the specific example embodiments
specifically
described herein.
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