Note: Descriptions are shown in the official language in which they were submitted.
CA 02819723 2013-07-02
MEDICAL FACE MASK WITH SEALING STRIP
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U.S.C. 119(e) to U.S.
Provisional Patent Application No. 61/819,969 filed May 6, 2013, which is
incorporated
by reference herein in its entirety.
BACKGROUND OF THE INVENTION
Face masks are often used as personal protective equipment in a variety of
situations, such as during medical treatment or in dusty environments. Medical
personnel,
such as nurses and surgeons, often need to wear face masks when providing care
to a
patient. Such face masks are generally designed to filter airborne
contaminants from the
air being inhaled by the user in order to protect the user from inhaling
pathogens and
other contaminants, while also protecting people near the user from inhaling
contaminants exhaled by the user. Such airborne contaminants may include
aerosolized
saliva, bacteria, viruses, dust, or any other type of particle that can be
suspended in air.
Face masks currently available are typically produced with one of two
types of protection. Both types of masks are made by a variety of different
manufacturers. The type of mask with the highest level of protection is the
N95 mask,
which refers to an efficiency rating determined by the National Institute for
Occupational
Safety and Health (NIOSH). The "N95" designation corresponds to a mask that
blocks
about 95% of particles that are 0.3 microns or larger. With testing for proper
fit, these
masks can provide good protection against inhaling harmful particles.
On the other hand, the type of mask used most frequently in healthcare
environments is the "surgical" or "procedure" mask. The surgical masks
presently
available do not provide a complete seal with the user's face, resulting in a
lower filtering
capability compared to N95 masks. However, these surgical masks are
significantly less
expensive than N95 masks. These surgical masks are typically constructed from
a fiat,
pleated filter material that spreads when the mask is worn. When the mask is
secured to
the user's face, gaps between the filter material and the wearer's face can
occur. While
these masks may protect the wearer from particles impacting directly against
the mask,
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they offer little or no protection from contaminants suspended in air that can
pass around
the edges of the mask into the wearer's lungs.
Thus, there is a continuing need in the art for a surgical face mask that
provides an improved seal with the user's face, but is less expensive than a
N95 mask.
The present invention addresses this unmet need in the art.
SUMMARY OF THE INVENTION
The present invention relates to a face mask for filtering contaminants
from air, comprising: an air-permeable body having an outer surface, an inner
surface,
and a perimeter, wherein the body is sized to cover the nose and mouth of a
subject when
worn by the subject; an inner seal connected to the inner surface of the body;
and at least
one strap connected to the body for securing the face mask to the subject's
face. In one
embodiment, the face mask may further comprise an outer seal connected to the
perimeter of the body.
In one embodiment, the air-permeable body is substantially rectangular in
shape. In one embodiment, a portion of at least one corner of the air-
permeable body is
folded towards the inner surface, thereby creating at least one two-layered
region of the
air-permeable body when worn by the subject. Accordingly, the width of the air-
permeable body at the two-layered region may be less than the width of the air-
permeable
body at it widest point. In another embodiment, the portion of the at least
one corner of
the air-permeable body that is folded towards that inner surface is attached
to the inner
surface of the air-permeable body.
In various embodiments, the face mask may comprise different lengths, for
example about 160 mm, 180 mm, 220 mm, or 230 mm. Further, in various
embodiments,
the face mask may comprise different widths at its widest point, for example
about 65 mm,
70 mm, 75 mm, or 85 mm. Further still, in various embodiments, the inner seal
may
comprise different widths, for example about 101 mm, 111 mm, or 134 mm
In one embodiment, the inner seal of the face mask of the present
invention is configured to form a seal around the subject's nose and mouth
when worn by
the subject. In other embodiment, the inner seal comprises at least one
leaflet for
conforming a portion of the inner seal to the subject's nose. In another
embodiment, the
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inner seal is connected to the inner surface of the body by at least one
connector strip or
connector tab.
In one embodiment, the body of the face mask of the present invention
comprises pleats for allowing the shape of the body to be adjusted. In another
embodiment, the body comprises a non-woven material. In one embodiment, the at
least
one strap comprises a clasp. In one embodiment, the face mask of the present
invention
filters at least about 95% of contaminants in air that are 0.3 microns or
larger, i.e., the
face mask meets N95 requirements.
In various embodiments, the inner seal and outer seal of the face mask of
the present invention comprise an elastomeric material. In one embodiment, the
inner seal
comprises silicone. In one embodiment, the outer seal comprises a TPE/EVA,
polyurethane (PU), or TPE/EVA/PU foam.
BRIEF DESCRIPTION OF THE DRAWINGS
The following detailed description of preferred embodiments of the
invention will be better understood when read in conjunction with the appended
drawings. For the purpose of illustrating the invention, there are shown in
the drawings
embodiments which are presently preferred. It should be understood, however,
that the
invention is not limited to the precise arrangements and instrumentalities of
the
embodiments shown in the drawings.
Figure 1 is an illustration showing the outside of a facial mask, according
to one embodiment of the present invention.
Figure 2 is an illustration showing a perspective view of the inside of a
facial mask, according to one embodiment of the present invention.
Figure 3 is an illustration showing the inside of a facial mask, according to
one embodiment of the present invention.
Figure 4 is an illustration showing the inside of a facial mask, according to
one embodiment of the present invention.
Figure 5 is an illustration showing the outside of a facial mask, according
to one embodiment of the present invention.
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Figure 6 is an illustration showing a perspective view of the outside of a
facial mask, according to one embodiment of the present invention.
Figure 7 is an illustration showing a perspective view of the inside of a
facial mask, according to one embodiment of the present invention.
Figure 8 is an illustration showing a perspective view of the inside of a
facial mask, according to one embodiment of the present invention.
Figure 9 is a set of illustrations showing the inner seal of a facial mask,
according to one embodiment of the present invention, wherein the inner seal
is
positioned on a user's face.
Figure 10 is an illustration showing a perspective view of the inside of a
facial mask, according to one embodiment of the present invention.
Figure 11 is a set of illustrations showing the inside of various
embodiments of the facial mask of the present invention.
Figure 12 is a set of illustrations of facial masks. Fig. 12A shows an inside
view and side view of a facial mask, according to one embodiment of the
present
invention. Fig. 12 13 shows an inside view and side view of a common facial
mask, i.e., a
mask currently available in the art.
Figure 13 is an illustration showing a perspective view of the inside of a
facial mask, according to one embodiment of the present invention.
Figure 14 is an illustration showing a perspective view of the outside of a
facial mask, according to one embodiment of the present invention.
DETAILED DESCRIPTION
It is to be understood that the figures and descriptions of the present
invention have been simplified to illustrate elements that are relevant for a
clear
understanding of the present invention, while eliminating, for the purpose of
clarity,
many other elements found in medical face masks. Those of ordinary skill in
the art may
recognize that other elements and/or steps are desirable and/or required in
implementing
the present invention. However, because such elements and steps are well known
in the
art, and because they do not facilitate a better understanding of the present
invention, a
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discussion of such elements and steps is not provided herein. The disclosure
herein is
directed to all such variations and modifications to such elements and methods
known to
those skilled in the art.
Unless defined otherwise, all technical and scientific terms used herein
have the same meaning as commonly understood by one of ordinary skill in the
art to
which this invention belongs. Although any methods, materials and components
similar
or equivalent to those described herein can be used in the practice or testing
of the present
invention, the preferred methods and materials are described.
As used herein, each of the following terms has the meaning associated
with it in this section.
The articles "a" and "an" are used herein to refer to one or to more than
one (i.e., to at least one) of the grammatical object of the article. By way
of example, "an
element" means one element or more than one element.
"About" as used herein when referring to a measurable value such as an
amount, a temporal duration, and the like, is meant to encompass variations of
20%,
10%, 5%, 1%, or 0.1% from the specified value, as such variations are
appropriate.
The terms "contaminant," "particle," and the like may be used
interchangeably herein, and refer to a constituent or impurity in the air or
environment
surrounding the user of the mask of the present invention that can adversely
affect the
user if inhaled.
Throughout this disclosure, various aspects of the invention can be
presented in a range format. It should be understood that the description in
range format
is merely for convenience and brevity and should not be construed as an
inflexible
limitation on the scope of the invention. Accordingly, the description of a
range should
be considered to have specifically disclosed all the possible subranges as
well as
individual numerical values within that range. For example, description of a
range such
as from 1 to 6 should be considered to have specifically disclosed subranges
such as from
1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc.,
as well as
individual numbers within that range, for example, 1, 2, 2.7, 3, 4, 5, 5.3, 6
and any whole
and partial increments therebetween. This applies regardless of the breadth of
the range.
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The present invention relates to a face mask that filters contaminants from
air during inhalation and exhalation. The face mask of the present invention
provides a more
complete seal than face masks in the prior art, thereby decreasing the risk of
contaminants
bypassing the face mask's filter during inhalation or exhalation. In one
embodiment, the
face mask comprises a seal within the mask that fits around the nose and mouth
of the user,
i.e., an inner seal. In another embodiment, the face mask comprises two seals
for sealing the
mask to the user's face: an inner seal and also a seal around the edge of the
mask, i.e., an
outer seal. The mask also comprises an air-permeable body that serves to
filter contaminants
from air and a mechanism for securing the mask to the user's face, for example
a strap that
connects to the mask and can be positioned around the user's head.
Referring now to the drawings, Fig. 1 is an illustration of one embodiment of
a face mask 10 of the present invention. Fig. 1 shows the outside of face mask
10,
comprising an air-permeable body 12 and straps 14. Straps 14 may be used to
secure face
mask 10 to the user's face by placing straps 14 around the user's ears. Air-
permeable body
12 of face mask 10 comprises a number of pleats 13 that allow for air-
permeable body 12 to
be stretched and configured without damaging or compromising the structural
integrity of
air-permeable body 12.
In one embodiment of the face mask of the present invention, the air-
permeable body 12 comprises a non-woven material or fabric. Non-woven
materials are
materials comprising fibers or filaments that are bound together mechanically,
thermally, or
chemically. The fibers or filaments are typically composed of synthetic
polymers, but can be
composed of any material suitable for both filtering particulates and
contacting human skin,
as would be understood by a person with ordinary skill in the art.
In one embodiment, straps 14 are configured to be placed around the ears of
the user. In another embodiment, the straps are configured to be placed around
the head or
neck of the user. In one embodiment, the straps comprise an elastomeric
material suitable
for securing the mask to the user's face. In another embodiment, the straps
further comprise
a clasping mechanism for securing the straps around the user's head or neck.
Referring to Fig. 2, an illustration of a perspective view of the inside of
face
mask 10 is shown, i.e., the side of face mask 10 that is in contact with the
user's face when
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face mask 10 is worn. Face mask 10 comprises air-permeable body 12, an inner
seal 16 and
an outer seal 18.
In one embodiment of the present invention, the inner seal 16 of the face
mask of the present invention comprises a relatively soft material that forms
a substantially
circular or elliptical shape around the user's nose and mouth when the mask is
worn.
Referring to Fig. 9, a series of illustrations shows inner seal 16 conforming
to a user's face.
In one embodiment, inner seal 16 further comprises wider or thicker regions,
also referred to
herein as leaflets 20, that conform to the shape of the user's face on either
side of the user's
nose to improve the sealing characteristics of inner seal 16. In one
embodiment, inner seal
16 comprises a region 22 between leaflets 20 that forms a seal with the bridge
of the user's
nose. In various embodiments, the length of region 22 may be sized
appropriately so that
leaflets 20 form a seal with the sides of the user's nose, i.e., so an optimal
seal is formed in
the area of the user's face where there are creases between the user's nose
and cheeks.
Further, in one embodiment, inner seal 16 comprises a side loop 23 that fits
around the side
of user's cheek in order to provide an optimal seal with the user's face. In
one embodiment,
the inner seal is made of silicone. In another embodiment, the inner seal may
comprise any
elastomeric material such as a thermoplastic elastomer (TPE), or a combination
of materials
such as TPE with ethylene-vinyl acetate (EVA) and/or polyurethane (PU),
suitable for
forming an air-tight seal around the user's nose and mouth.
In one embodiment, the outer seal 18 of the present invention comprises a
relatively soft material that can conform to the contours of the user's face
in order to form an
air-tight seal between the air-permeable body of the present invention and the
user's face. In
one embodiment, the outer seal comprises foam made from a TPE/EVA blended
resin. In
another embodiment, the foam of the outer seal comprises polyurethane. In
another
embodiment, the outer seal may comprise any material, or combination of
materials, suitable
for forming an air-tight seal between the mask and the user's face. In yet
another
embodiment, the face mask of the present invention may comprise only one seal,
wherein
the single seal is an outer seal instead of an inner seal.
In one embodiment, a mild adhesive may be used in conjunction with the
inner seal, outer seal, or both, in order to further improve the quality of
the seal between the
mask and the user's face. In another embodiment, the inner seal, outer seal,
or both, may
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comprise an elastomeric material that is formulated to produce a sticky or
tacky effect, in
order to further improve the quality of the seal between the mask and the
user's face
Referring to Fig. 3, an illustration of the inside of face mask 10 is shown.
Face mask 10 comprises straps 14, inner seal 16, and outer seal 18. Inner seal
16 is attached
to face mask 10 at two points via connector strips 15. The dimensions of
various parts of an
exemplary embodiment of face mask 10 are also shown in Fig. 3, in millimeters
(mm). Fig.
3 shows one possible configuration of face mask 10, in which air-permeable
body 12 and
inner seal 16 are not stretched vertically, i.e., the inner seal is in a
relaxed state. Specifically,
the height of air-permeable body 12 is about 60 mm at all points, while the
width of inner
seal 16 is about 150 mm. The overall width of air-permeable body 12 is about
230 mm.
In various embodiments, the face mask of the present invention can be
configured or adjusted to fit the contours of the user's face. In one
embodiment, pleats 13 in
the air-permeable body 12 allow for the body to be stretched to match the
dimensions of the
user's face. In one embodiment, outer seal 18 is suitably flexible to stretch
or adjust in
conjunction with air-permeable body 12 without separating or detaching from
air-permeable
body 12.
In one embodiment, inner seal 16 is attached to air-permeable body 12 via at
least one connector strip 15. In a preferred embodiment, inner seal 16 is
attached to air-
permeable body 12 via two connector strips, such that the inner seal 16 can
maintain
sufficient flexibility to change shape when air-permeable body 12 is adjusted
vertically,
while remaining connected to air-permeable body 12. In one embodiment, each
connector
strip 15 serves to fasten inner seal 16 to air-permeable body 12 in a single
location, thereby
leaving the remaining portion of inner seal 16 unconnected to air-permeable
body 12. In
such an embodiment, most of inner seal 16 is free-floating, i.e., unconnected
to air-
permeable body 12 or any other part of face mask 10, in order to allow inner
seal 16 to
adjust and conform to the user's face when worn by the user. In one
embodiment, inner seal
16 is forced against air-permeable body 12 when worn by the user, thereby
forming a seal
between inner seal 16 and air-permeable body 12, in addition to the seal
formed between
inner seal 16 and the user's face. In such an embodiment, the seal formed
between inner seal
16 and air-permeable body 12 is a mechanical seal resulting from the pressure
of inner seal
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16 against air-permeable body 12 caused by the force of the user's face
pushing against
inner seal 16.
Referring to Fig. 4, an illustration of the inside of face mask 10 is shown,
in
which a portion of face mask 10 has been stretched to match the dimensions of
a user's face,
i.e., to cover the user's nose and mouth. Specifically, the height of air-
permeable body 12 is
about 130 mm at its fully expanded point, while the width of inner seal 16 is
about 100 mm
(compared to 150 mm in Fig. 3). Notably, the overall width of air-permeable
body 12 is
about 230 mm, i.e., the same as in Fig. 3. Therefore, as depicted in Fig. 4,
inner seal 16 and
a portion of air-permeable body 12 have been stretched vertically without
substantially
changing the overall width of air-permeable body 12. Further, the shape of
outer seal 18 has
been adjusted accordingly with air-permeable body 12.
Referring to Fig. 5, an illustration of the outside of face mask 10 is shown,
in
which air-permeable body 12 has been configured to cover the user's nose and
mouth. As
described herein, air-permeable body 12 comprises pleats 13 that enable air-
permeable body
12 to be stretched without reducing or compromising the structural integrity
of air-
permeable body 12.
Referring to Fig. 6, an illustration of a perspective view of the outside of
face
mask 10 is shown. Connector strips 15 are used to attach the inner seal 16
(not shown) to
air-permeable body 12 of face mask 10. In this view, face mask 10 is
configured to the
approximate shape of face mask 10 when it is secured to a user's face. In this
embodiment,
straps 14 may be secured around the user's ears to secure face mask 10 to the
user's face,
while air-permeable body 12 is configured to cover the user's nose and mouth.
Referring to Fig. 7, an illustration of a perspective view of the inside of
face
mask 10 is shown. In this embodiment, air-permeable body 12 and inner seal 16
are
configured to cover the user's nose and mouth, similarly to Fig. 6. Outer seal
18 maintains
the shape of the perimeter of air-permeable body 12. Connector strips 15
connect inner seal
16 to air-permeable body 12. Further, inner seal 16 comprises leaflets 20,
i.e., a wider region
of the inner seal, that provide an optimal fit of inner seal 16 to the bridge
of the user's nose.
As contemplated herein, inner seal may include additional leaflet regions to
provide
additional depth and/or thickness to better conform to the user's facial
contours, such as
around the cheeks, mouth and portion of the chin.
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Referring to Fig. 8, an illustration of a perspective view of face mask 10,
comprising inner seal 16 is shown.
Referring to Fig. 10, an illustration of the inside of another embodiment of
the face mask of the present invention is shown. Face mask 30 comprises an air-
permeable
body 12, straps 14, and an inner seal 16.Inner seal 16 is connected to air-
permeable body 12
via connector tabs 26. Inner seal 16 comprises a bottom region 24 that is
wider than other
areas of inner seal 16, much like leaflets 20. Bottom region 24 may be
suitable for forming a
seal with an area on user's chin. Air-permeable body 12 of face mask 30
comprises angled
regions 32, wherein the height of air-permeable body 12 reduces from its
widest point to its
narrowest point near the part of face mask 30 where straps 14 are connected.
In one
embodiment, angled region 32 is created by manufacturing air-permeable body 12
in a
shape that is generally rectangular, but with a sloping angle near the ends of
the rectangle,
i.e., a reduced width at each of the four corners of the rectangle as compared
to the width at
the center of the rectangle.
In another embodiment, angled regions 32 are created by manufacturing air-
permeable body 12 in the shape of a rectangle, then folding each of the four
corners of the
rectangle toward the inside surface of air-permeable body 12. An example of
such an
embodiment is shown in Figure 11. In Fig. 11, four embodiments of face mask 30
are
shown, wherein each embodiment comprises the same shape and features, but with
different
dimensions, as indicated. Angled regions 32 are shown on air-permeable body
12, wherein a
portion of air-permeable body 12 has been folded to create flaps 34 at each
corner of air-
permeable body 12. Accordingly, a region near each of the four comers of air-
permeable
body 12 has two layers of material where flaps 34 have been folded. Flaps 34
may improve
the seal between the user's face and air-permeable body 12 by increasing the
stiffness of at
least a portion of air-permeable body 12, which may prevent undesired folding
of face mask
when worn by the user. Further, flaps 34 may be used to secure, or aid in
securing, straps
14 to air-permeable body 12. In one embodiment, flaps 34 may be secured to the
inner
surface of air-permeable body by any means that would be understood by a
person of
ordinary skill, for example, but not limited to, an adhesive or a clamp.
30 In addition, the width of the region of air-permeable body 12 that
has been
folded to form flaps 34 is less than other regions of air-permeable body 12.
In one
CA 02819723 2013-07-02
embodiment, this reduced width at the ends of air-permeable 12 may improve the
seal of the
face mask of the present invention to the user's face by providing a narrower
region where
straps 14 can connect to face mask 30. Such a narrow region may reduce the
possibility of
folds or gaps being created when the straps are attached to the user, for
example when straps
14 are placed around the user's ears.
As shown in Fig. 11, in various embodiments, face mask 30 may comprise
different lengths, for example 160 mm, 180 mm, 220 mm, or 230 mm. Further,
face mask
30 may comprise different widths at its widest point, for example 65 mm, 70
mm, 75 mm,
or 85 mm. Further still, inner seal 16 may comprise different widths, for
example 101 mm,
111 mm, or 134.36 mm. However, as would be understood by a person with
ordinary skill
in the art, the present invention is not limited to the dimensions described
herein.
In one embodiment, face mask 30 differs from face mask 10 by eliminating
the outer seal of face mask 10. Accordingly, flaps 34 may create an air-tight
seal between
the user's face and face mask 30 without the need for an outer seal. However,
in another
embodiment, at least a portion of the perimeter of air-permeable body 12 of
face mask 30
comprises an outer seal.
Referring to Fig. 12, a comparison between an embodiment of the face mask
of the present invention and an embodiment of a face mask currently available
is shown,
including some relevant dimensions of both face masks. The diagram at the left
of Fig. 12A
shows the inside of face mask 30 of the present invention, wherein the diagram
at the right
shows the profile of face mask 30. The image at the left of Fig. 12 B shows
the inside of a
face mask of a type currently available wherein the image at the right shows
the profile of
the face mask currently available. As can been seen in Fig. 12, this
embodiment of face
mask 30 differs from the currently available face mask in a number of respects
such as, but
not limited to: face mask 30 is substantially longer than the face mask in
Fig. 12B (220 mm
vs, 175 mm, excluding the size of the ear straps); face mask 30 comprises an
inner seal 16,
whereas the mask in Fig. 12B does not; and ear straps 14 of face mask 30 are
connected to
the mask to allow for flaps 34 to be folded, while the mask in Fig. 12B does
not have such
flaps, and could not have such flaps, because the ear straps of the mask in
Fig. 12B are
connected close to the edge of the corners of the rectangle.
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Accordingly, these differences between face mask 30 and the face mask in
Fig. 12B, at least, result in improved sealing of face mask 30 to the user's
face when
compared to the mask in Fig. 12B. For example, the longer size of face mask
30, along with
flaps 34, optimizes the seal of the mask at the sides of the user's face,
i.e., the area of the
user's face closest to the user's ears. In addition, the inner seal of face
mask 30 creates an
air-tight seal around the user's nose and mouth. Conversely, the face mask in
Fig. 12B
allows for gaps between the mask and the user's face when worn by the user,
created, for
example, by the body of the mask folding or bunching, or by the lack of a
mechanism
properly adhere the mask to the different contours of the user's face.
Accordingly, the mask
in Fig. 12B cannot provide an optimal, air-tight seal to all portions of the
user's face.
Referring to Fig. 13, an illustration of one embodiment of the inside of face
mask 30 is shown, comprising angled regions 32. In this embodiment, an
embodiment of
inner seal 16 is shown, wherein inner seal 16 comprises a region 22 between
leaflets 20 that
is wide enough to form an optimal seal with the bridge of the user's nose.
Referring to Fig. 14, an illustration of a perspective view of the outside of
face mask 30 is shown.
The disclosures of each and every patent, patent application, and
publication cited herein are hereby incorporated herein by reference in their
entirety.
While this invention has been disclosed with reference to specific
embodiments, it is apparent that other embodiments and variations of this
invention may
be devised by others skilled in the art without departing from the true spirit
and scope of
the invention. The appended claims are intended to be construed to include all
such
embodiments and equivalent variations.
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