U.S. patent application number 12/002064 was filed with the patent office on 2009-06-18 for respirator with stretch-panels.
Invention is credited to Eric C. Steindorf, Debra N. Welchel.
Application Number | 20090151733 12/002064 |
Document ID | / |
Family ID | 40751608 |
Filed Date | 2009-06-18 |
United States Patent
Application |
20090151733 |
Kind Code |
A1 |
Welchel; Debra N. ; et
al. |
June 18, 2009 |
Respirator with stretch-panels
Abstract
A disposable respirator made from a filter body having at least
one stretch-panel incorporated therein. The stretch-panel allows
the respirator to better conform to the wearer's face during
movement due to talking, coughing, or general head or neck
movement. There may be one or more stretch-panels located
underneath the chin or over the cheeks of the wearer.
Inventors: |
Welchel; Debra N.;
(Woodstock, GA) ; Steindorf; Eric C.; (Roswell,
GA) |
Correspondence
Address: |
KIMBERLY-CLARK WORLDWIDE, INC.;Catherine E. Wolf
401 NORTH LAKE STREET
NEENAH
WI
54956
US
|
Family ID: |
40751608 |
Appl. No.: |
12/002064 |
Filed: |
December 13, 2007 |
Current U.S.
Class: |
128/863 |
Current CPC
Class: |
A41D 13/113 20130101;
A62B 23/025 20130101 |
Class at
Publication: |
128/863 |
International
Class: |
A41D 13/11 20060101
A41D013/11 |
Claims
1. A disposable respirator which defines an area surrounded by a
periphery, the disposable respirator extending across a wearer's
nose bridge, across each of the wearer's cheeks, and underneath the
wearer's chin for covering the nose and mouth of the wearer, the
disposable respirator comprising: a filter body comprising a
non-elastic material defining a body outer surface area; and a
first stretch-panel comprising an elastic material and having an
outer edge defining a portion of the mask periphery, the first
stretch-panel defining a panel outer surface area, wherein the
panel outer surface area is less than the filter outer surface
area.
2. The disposable respirator of claim 1 wherein the first
stretch-panel comprises a stretch direction that is about parallel
with the outer edge of the first stretch-panel.
3. The disposable respirator of claim 1 wherein the first
stretch-panel is substantially triangular in shape.
4. The disposable respirator of claim 1 wherein the first
stretch-panel is air impermeable.
5. The disposable respirator of claim 1 wherein the first
stretch-panel is attached to the filter body with a thermal
bond.
6. The disposable respirator of claim 1 further comprising a head
strap, wherein the head strap is connected to the filter body.
7. The disposable respirator of claim 1 further comprising a second
stretch-panel, wherein the first stretch-panel and the second
stretch-panel are attached to the filter body, and wherein the
panel outer surface area is defined by the outer surface area of
the first stretch-panel and the outer surface area of the second
stretch-panel.
8. The disposable respirator of claim 7 wherein the first and the
second stretch-panels are substantially triangular in shape.
9. The disposable respirator of claim 7 wherein the first and the
second stretch-panels comprise four-sided polygons.
10. The disposable respirator of claim 7 wherein the first
stretch-panel and the second stretch-panel are spaced apart and
arranged to fit over each of the wearer's cheeks.
11. The disposable respirator of claim 7 wherein the first
stretch-panel and the second stretch-panel are connected
together.
12. The disposable respirator of claim 1 further comprising an
exhalation vent located on the filter body or the first
stretch-panel.
13. The disposable respirator of claim 1 wherein the filter body
comprises a sheet-like blank that is symmetric about a fold
line.
14. The disposable respirator of claim 13 wherein the first
stretch-panel comprises a fold line such that when the respirator
is in a flat configuration, the stretch-panel is folded inward
toward a body-facing surface of the respirator.
15. The disposable respirator of claim 13 wherein the first
stretch-panel is symmetrically disposed on the mask with respect to
the fold line.
16. The disposable respirator of claim 15 wherein the connection
between the filter body and the first stretch-panel is air
impermeable.
17. The disposable respirator of claim 1 wherein the first
stretch-panel comprises an elastic film.
18. The disposable respirator of claim 17 wherein the first
stretch-panel comprises a stretch bonded laminate.
19. A disposable respirator for a wearer, the respirator
comprising: a filter body sized to fit over the mouth and nose of
the wearer, the filter body having a top edge arranged to extend
across the nose and cheeks of the wearer, a bottom edge arranged to
extend along a wearer's jaw line, and a seam edge arranged to
extend between the wearer's nose to the wearer's chin; and a
triangular stretch-panel attached to the bottom edge of the filter
body, wherein the stretch-panel is arranged to fit underneath the
wearer's chin.
20. A disposable respirator for a wearer, the respirator
comprising: a filter body sized to fit over the mouth and nose of
the wearer, the filter body having a top edge arranged to extend
across a nose and upper cheeks of the wearer, and a bottom edge
arranged to extend along lower cheeks and underneath a chin of the
wearer, wherein the bottom edge has two spaced apart notched
portions; and a seam edge arranged to extend between the wearer's
nose to the wearer's chin; and a stretch-panel disposed within each
of the of notched portions and attached to the filter body.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to filter masks which isolate both the
mouth and nostrils of a wearer from the surrounding environment.
More particularly, the invention relates to a conforming,
collapsible filter mask which requires only a headband to secure
the filter mask to the wearer's head.
[0002] There are many situations today where it is necessary to
filter the air which is inhaled and exhaled. Such filtration is
primarily concerned with removal of small particulate matter, such
as dirt or bacteria, as opposed to gases or liquids, from the air.
Perhaps the most common instance in which a filter mask is used is
in the medical arts. However, the same filter masks which have
application in the medical arts are also, in many cases, well
suited for use in industrial and domestic applications.
[0003] In the medical arts, filter masks are often used to prevent
substances exhaled by the wearer from entering the surrounding
environment. The same mask may also be used to protect the wearer
from inhaling harmful microorganisms. One of the more common
applications of filter masks in the medical arts is the wearing of
masks by a surgical team while performing surgical procedures. A
mask worn during surgical procedures, for example, desirably
provides proper air filtration while still being comfortable for
the wearer who may be wearing the same mask for several hours.
[0004] In the industrial arts it is often necessary for individuals
working in "clean room" environments to avoid the introduction of
any substances which may be exhaled by the wearer, into the clean
room environment. As in the medical arts applications, industrial
applications may require the workers to wear their filter masks for
extended periods of time. Therefore, it is desirable that a mask be
comfortable and durable.
[0005] Other industrial applications require the filtration of the
air which is inhaled by the wearer. Often construction or
agricultural workers will be working in a "dirty" environment in
which the air would be harmful to breathe if it were not filtered.
Many times filter masks are used in such circumstances to protect
the wearer from harm. Unfortunately, many workers will simply go
without a protective mask if they deem it too uncomfortable.
[0006] Besides the medical and industrial applications there are
domestic applications for such masks in the home such as home
improvement projects, particularly those involving sanding or
cutting, yard work, and many hobbies.
[0007] Regardless of the application, the full benefits of the
filter mask will not be realized if inhaled or exhaled air is
allowed to leak around the edges of the mask when held against the
wearer's face. However, it is challenging to construct a mask that
will fit the facial configuration of all wearers without
constructing the mask specifically for each individual face.
Compounding this challenge is the fact that a wearer's face
naturally moves and changes in shape while wearing a mask. This can
happen when the wearer talks, chews, yawns, stretches, or the
like.
[0008] It is therefore very desirable to design a mask that is
relatively quick and easy to place on the face, and that will
remain in the proper position while the wearer continues his or her
ordinary activities. It is further desirable to design a mask that
is compact. Generally, a flat storage configuration provides for
the most compact storage. Moreover, it is desirable that a mask be
economical, since most users of filter masks dispose of the mask
after limited use.
SUMMARY OF THE INVENTION
[0009] The present invention includes a disposable respirator which
defines an area surrounded by a periphery, the disposable
respirator extending across a wearer's nose bridge, across each of
the wearer's cheeks, and underneath the wearer's chin for covering
the nose and mouth of the wearer. The disposable respirator
includes a filter body comprising a non-elastic material defining a
first area, and a first stretch-panel having an outer edge defining
a portion of the mask periphery, the first stretch-panel defining a
second area. The first stretch-panel is an elastic material. The
area of the first stretch-panel is less than the area of the filter
body.
[0010] In another aspect of the present invention, the respirator
is made with a filter body sized to fit over the mouth and nose of
the wearer, the filter body having a top edge arranged to extend
across the nose and cheeks of the wearer, a bottom edge arranged to
extend along a wearer's jaw line, and a seam edge arranged to
extend between the wearer's nose to the wearer's chin; and a
triangular elastic panel attached to the bottom edge of the filter
body, wherein the stretch-panel is arranged to fit underneath the
wearer's chin.
[0011] In yet another aspect of the present invention, the
respirator is made from a filter body sized to fit over the mouth
and nose of the wearer, the filter body having a top edge arranged
to extend across a nose and upper cheeks of the wearer; a bottom
edge arranged to extend along lower cheeks and underneath a chin of
the wearer, wherein the bottom edge has two spaced apart notched
portions; and a seam edge arranged to extend between the wearer's
nose to the wearer's chin; and a stretch-panel disposed within each
of the of notched portions and attached to the filter body.
[0012] Other aspects and features will be in part apparent and in
part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A full and enabling disclosure of the present invention,
including the best mode thereof, directed to one of ordinary skill
in the art, is set forth more particularly in the remainder of the
specification, which makes reference to the appended figures in
which:
[0014] FIG. 1 is a side elevation of one embodiment of the
respirator of the present invention in a flat folded
configuration.
[0015] FIG. 2 is an exploded plan view of the various parts used to
construct the respirator of FIG. 1, prior to assembly.
[0016] FIG. 3 is a rear elevation of the respirator shown in FIG.
1, in an unfolded configuration.
[0017] FIG. 4 is a front perspective view of the respirator in FIG.
1 shown on the face of a wearer with his head in a rearward tilt
position.
[0018] FIG. 5 is a front perspective view of the respirator of FIG.
1, shown on the face of a wearer with his head in an upright
position.
[0019] FIG. 6 is a front elevation of a second embodiment of the
respirator of the present invention in a flat-fold
configuration.
[0020] FIG. 7 is a side elevation of a second embodiment of the
respirator of the present invention shown on the face of a
wearer.
[0021] FIG. 8 is a side elevation of a third embodiment of the
respirator of the present invention.
[0022] FIG. 9 is a side elevation of a fourth embodiment of the
respirator of the present invention.
[0023] FIG. 10 is a side elevation of a fifth embodiment of the
respirator of the present invention.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
[0024] The following definitions are used in the description of the
present invention.
[0025] "Attach" and its derivatives refer to the joining, adhering,
connecting, bonding, sewing together, or the like, of two elements.
Two elements will be considered to be attached together when they
are integral with one another or attached directly to one another
or indirectly to one another, such as when each is directly
attached to intermediate elements. "Attach" and its derivatives
include permanent, releasable, or refastenable attachment. In
addition, the attachment can be completed either during the
manufacturing process or by the end user.
[0026] "Connect" and its derivatives refer to the joining,
adhering, bonding, attaching, sewing together, or the like, of two
elements. Two elements will be considered to be connected together
when they are connected directly to one another or indirectly to
one another, such as when each is directly connected to
intermediate elements. "Connect" and its derivatives include
permanent, releasable, or refastenable connection. In addition, the
connecting can be completed either during the manufacturing process
or by the end user.
[0027] The terms "disposed on," "disposed along," "disposed with,"
or "disposed toward" and variations thereof are intended to mean
that one element can be integral with another element, or that one
element can be a separate structure bonded to or placed with or
placed near another element.
[0028] "Layer" when used in the singular can have the dual meaning
of a single element or a plurality of elements.
[0029] "Spunbonded fibers" refers to small diameter fibers which
are formed by extruding molten thermoplastic material as filaments
from a plurality of fine, usually circular capillaries of a
spinneret with the diameter of the extruded filaments then being
rapidly reduced to fibers as by, for example, in U.S. Pat. No.
4,340,563 to Appel et al., and U.S. Pat. No. 3,692,618 to Dorschner
et al., U.S. Pat. No. 3,802,817 to Matsuki et al., U.S. Pat. Nos.
3,338,992 and 3,341,394 to Kinney, U.S. Pat. No. 3,502,763 to
Hartman, and U.S. Pat. No. 3,542,615 to Dobo et al., the contents
of which are incorporated herein by reference in their entirety.
Spunbond fibers are generally continuous and have diameters
generally greater than about 7 microns, more particularly, between
about 10 and about 20 microns.
[0030] "Stretch bonded laminate" refers to a composite material
having at least two layers in which one layer is a gatherable layer
and the other layer is an elastic layer. The layers are joined
together when the elastic layer is extended from its original
condition so that upon relaxing the layers, the gatherable layer is
gathered. Such a multilayer composite elastic material may be
stretched to the extent that the non-elastic material gathered
between the bond locations allows the elastic material to elongate.
One type of stretch bonded laminate is disclosed, for example, by
U.S. Pat. No. 4,720,415 to Vander Wielen et al., the content of
which is incorporated herein by reference in its entirety. Other
composite elastic materials are disclosed in U.S. Pat. No.
4,789,699 to Kieffer et al., U.S. Pat. No. 4,781,966 to Taylor and
U.S. Pat. Nos. 4,657,802 and 4,652,487 to Morman and U.S. Pat. No.
4,655,760 to Morman et al., the contents of which are incorporated
herein by reference in their entirety.
[0031] "Necking" or "neck stretching" interchangeably refer to a
method of elongating a nonwoven fabric, generally in the machine
direction, to reduce its width (cross-machine direction) in a
controlled manner to a desired amount. The controlled stretching
may take place under cool, room temperature or greater temperatures
and is limited to an increase in overall dimension in the direction
being stretched up to the elongation required to break the fabric,
which in most cases is about 1.2 to 1.6 times. When relaxed, the
web retracts toward, but does not return to, its original
dimensions. Such a process is disclosed, for example, in U.S. Pat.
No. 4,443,513 to Meitner and Notheis, U.S. Pat. Nos. 4,965,122,
4,981,747 and 5,114,781 to Morman and U.S. Pat. No. 5,244,482 to
Hassenboehier Jr. et al., the contents of which are incorporated
herein by reference in their entirety.
[0032] "Ultrasonic bonding" refers to a process in which materials
(fibers, webs, films, etc.) are joined by passing the materials
between a sonic horn and anvil roll. An example of such a process
is illustrated in U.S. Pat. No. 4,374,888 to Bornslaeger, the
content of which is incorporated herein by reference in its
entirety.
[0033] "Thermal point bonding" involves passing materials (fibers,
webs, films, etc.) to be bonded between a heated calender roll and
an anvil roll. The calender roll is usually, though not always,
patterned in some way so that the entire fabric is not bonded
across its entire surface, and the anvil roll is usually flat. As a
result, various patterns for calender rolls have been developed for
functional as well as aesthetic reasons. Typically, the percent
bonding area varies from around 10 percent to around 30 percent of
the area of the fabric laminate. As is well known in the art,
thermal point bonding holds the laminate layers together and
imparts integrity to each individual layer by bonding filaments
and/or fibers within each layer.
[0034] "Elastic" refers to any material, including a film, fiber,
nonwoven web, or combination thereof, which upon application of a
biasing force in at least one direction, is stretchable to a
stretched, biased length which is at least about 110 percent,
suitably at least about 130 percent, and particularly at least
about 150 percent, its relaxed, unstretched length, and which will
recover at least 15 percent of its elongation upon release of the
stretching, biasing force. In the present application, a material
need only possess these properties in at least one direction to be
defined as elastic.
[0035] "Recover" or "recovery" refers to a contraction of a
stretched material upon termination of a biasing force following
stretching of the material by application of the biasing force. For
example, if a material having a relaxed, unbiased length of one (1)
inch is elongated 50 percent by stretching to a length of one and
one half (1.5) inches the material would have a stretched length
that is 150 percent of its relaxed length. If this exemplary
stretched material contracted, that is recovered to a length of one
and one tenth (1.1) inches after release of the biasing and
stretching force, the material would have recovered 80 percent (0.4
inch) of its elongation.
[0036] "Polymer" generally includes but is not limited to,
homopolymers, copolymers, such as for example, block, graft, random
and alternating copolymers, terpolymers, etc. and blends and
modifications thereof. Furthermore, unless otherwise specifically
limited, the term "polymer" shall include all possible geometrical
configurations of the molecule. These configurations include, but
are not limited to isotactic, syndiotactic and random
symmetries.
[0037] These terms may be defined with additional language in the
remaining portions of the specification.
[0038] Reference will now be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation of the
invention, and not meant as a limitation of the invention. For
example, features illustrated or described as part of one
embodiment can be used with another embodiment to yield still a
third embodiment. It is intended that the present invention include
these and other modifications and variations.
[0039] The present invention is a respirator 10 that is generally
constructed from a filter body 12 and one or more stretch-panels
14, exemplified by panels 14A and 14B in FIGS. 1-10. As shown,
respirator 10 preferably has the general shape of a cup defining an
opening 11 that is generally against the wearer's face when worn
(see, FIG. 3). The filter body portion of the mask 10 is preferably
held away from the wearer's nostrils and mouth. Such "off-the-face"
style masks provide a breathing chamber to permit cooler wear and
easier breathing.
[0040] The respirator is intended to be disposable, that is, used
for a limited period of time and disposed of rather than washed or
otherwise rejuvenated for reuse. The stretch-panel(s) 14 may be
located at various locations of the respirator providing that it
coincides with the mask periphery 16. Thus, a stretch-panel 14 at
the mask periphery 16 may desirably stretch in a direction that is
approximately tangent or parallel to the periphery 16 so that the
periphery 16 can selectively increase in size as needed. More
detailed non-limiting examples of the present invention are
described below.
[0041] A first exemplary embodiment of the respirator 10, shown in
FIGS. 1-5, may be constructed from a unitary filter body 12 and a
single stretch-panel 14, specifically referred to as panel 14A.
Desirably, filter body 12 is formed from one of more layers of
material as described below. The filter body may be cut into a
blank that is symmetric about a fold line 18. A fold is formed at
fold line 18 when the constructed mask 10 is in a flat
configuration (see FIGS. 1 and 2). Instead of the unitary body
blank shown in FIG. 2, it is contemplated that two or more separate
parts may form the filter body 12.
[0042] Referring now to FIG. 2, the overall shape of filter body 12
is defined by a top edge 22 flanked by a pair of side edges 24,
which together extend across the nose bridge and along the cheeks
of the wearer; a pair of bottom edges 25 that when joined together,
extend along the lower jaw of a wearer (see FIG. 4); and a pair of
seam edges 26 that converge together from the inner end of each
bottom edge 25 to the lower end of the fold line 18. Each edge 22,
24, 25 and/or 26 may be curved as shown, or a may have an angular
configuration. It is desirable to have the some type of headband
attachment structure located near each junction of edges 22 and 24,
referenced as points "A" and "B" in FIG. 2. For instance, side edge
24 may be shaped to define tab members 27, used to accommodate a
headband attachment structure as described below.
[0043] Respirator 10 has an outer surface area (viewable when the
mask is worn), and an opposite inner surface area. The outer
surface area of the respirator 10 is defined as the sum of the
filter body 12 outer surface area and the stretch-panel 14A outer
surface area, minus any margins used to connect these components
together. For embodiments having more than one stretch-panel, the
outer surface of stretch-panel 14 is the sum of the individual
outer surface areas for each stretch-panel.
[0044] Independent of any particular embodiment of respirator 10,
the type of filter materials and/or media used may depend on the
intended end use of the respirator by a consumer. For instance,
different uses will require different levels of filtration, which
is beyond the scope of the present invention. Desirably, the
combined layers of the filter body provide structural stiffness
such that mask 10 does not collapse against the nose and mouth
while being worn.
[0045] As noted, suitable materials for the filter body 12 may
include one or more layers of material. In one embodiment, there
are two layers of material. Outer layer 60 may be formed from a
material that is (a) gas permeable such that it permits air to pass
through filter body 12 in both directions, and (b) liquid
impermeable such that it prevents liquid from passing through layer
60 in at least one direction. Layer 60 is preferably arranged to
help prevent the passage of liquids from the exterior of mask 10 to
the interior of mask 10.
[0046] In another embodiment, filter body 12 is a three layer
structure that includes an outer mask layer 60, an inner mask layer
62, and a middle layer (not shown). In one particular embodiment,
filter body 12 may include outer mask layer 60 that is constructed
from a spun-bonded polypropylene that may have a 30.5 gsm basis
weight. Alternative materials for outer mask layer 60 include, but
are not limited to, thermally-formed polyester-bonded carded web,
bi-component and/or powder bonded polyethylene or polypropylene
nonwovens, wet-laid nonwovens, cellulosic tissue, or a spunbond
polyester. The basis weight of these materials may range from about
15 to about 200 gsm.
[0047] Inner mask layer 62 may be constructed from the same
materials as layer 60, or a in the alternative, a composite made
from bicomponent polyethylene and polypropylene, or a composite
made from bicomponent polyethylene and polyester. Layer 62 may also
be constructed from a polyester and/or polyethylene material or a
cellulosic tissue. In one particular embodiment, layer 62 is a
thermally formed blended fiber bonded carded web. Desirably, layer
62 may have a basis weight of about 17 gsm.
[0048] Selection of the number and type of the middle layers of
filter media, which may be disposed between outer mask layer 60 and
inner mask layer 62, can depend on the degree and type of
filtration required by the wearer. Suitable mediums for the middle
layer include, but are not limited to, melt-blown polypropylene,
extruded polycarbonate, melt-blown polyester, or melt-blown
urethane, bicomponent spunbond and/or an expanded
polytetrafluoroethylene (PTFE) membrane. In one particular
embodiment, the middle layer may be a filtrating material such as
electret-treated meltblown polypropylene having a basis weight of
roughly 70 gsm, or alternatively, in the range of about 30 to about
120 gsm. Further, the middle layer may be a combination of lighter
weight layers which together, add up to the desired basis weight.
In one non-limiting example, the middle layer may be a laminate
formed from a two plies of 50 gsm sheets.
[0049] Stretch-panel 14A may have various shapes. For example, as
seen in FIG. 2, stretch-panel 14A is basically a triangular wedge.
It is contemplated that stretch-panel 14A may be asymmetric or
symmetric as shown. Further, stretch-panel 14A may be a truncated
ovoid, a rectangle, or even a decorative shape such as a lightning
bolt. If there is more than one stretch-panel (as seen in latter
embodiments of the present invention) they do not need to be
identical shapes. Regardless of the exact shape of any
stretch-panel 14, it will characteristically have an edge, such as
edge 28, coincides with the periphery 16. Because the stretch-panel
is designed to stretch, the shape desirably provides adequate area
adjacent the edge 28, and an adequate length for edge 28, so as not
to prevent or limit stretching.
[0050] In the specific embodiment of FIG. 2, stretch-panel 14 is
symmetric in shape and has a pair of sides 25' which correspond in
length to the bottom edges 25 on filter body 12. Desirably, the
length of side 25 is about equal to the length of side 25'. Most
desirably, the triangular shape is truncated to create a short side
29. The purpose of truncation is to lessen the amount of material
that comes together when seam 26 is created, specifically, at the
outer end 30 of seam edges 26. This reduction of material will
create a cleaner and more flexible seam.
[0051] Regardless of the stretch-panel location, stretch-panel 14
is desirably constructed from a material that is stretchable in at
least one direction, and air impermeable. The term "stretchable"
describes a material that can stretch yet substantially recover to
its initial pre-stretched dimension. The term "air impermeable"
means that for all practical purposes, the wearer cannot breathe
through the stretch-panel 14. One direction of stretch will
substantially align with the periphery edge 16. If periphery edge
16 is a straight edge, it is desirable that the stretch direction
be about parallel with periphery 16. If periphery 16 is a curved
edge, it is desirable that the stretch direction be about parallel
with a tangent of periphery 16 taken at about the midpoint of a
stretch-panel edge 28.
[0052] Suitable materials for the stretch-panel 14 include, but are
not limited to, films, nonwovens, or laminates that may include an
elastic component such as natural rubber latex, urethanes, elastic
block copolymers (e.g. KRATON.RTM. from Kraton Polymers LLC or
VISTAMAXX.TM. from ExxonMobil Chemical Co.). Laminates may be in
the form of necked materials such as necked bonded nonwovens, or
single- or dual-faced elastic film laminates such as stretch bonded
laminates. Desirably, these stretch-panel 14 materials can be
stretched to at least about 30% of an original length. However, it
may be more desirable that such materials may be stretchable up to
about 100% of an original length, and most desirable that such
materials may be stretchable up to about 200% of an original
length. The stretch-panel material may be air impermeable, or have
a greater filtration performance (e.g. higher density, less porous,
etc.) throughout the entire range of stretch than filter body
12.
[0053] Referring to FIG. 1, inside of top edge 22 of the mask 10,
there may be an elongated malleable strip 52 as shown in FIGS. 1-3
and 5. Malleable strip 52, known in the respirator art, is provided
so that top edge 22 of mask 10 can be configured to closely fit the
contours of the nose of the wearer. In order to reduce "blow-by"
associated with normal breathing of the wearer, malleable strip 52
is preferably positioned at about the center of top edge 22 and has
a length in the range of about 40 percent to about 70 percent of
the total length of the top edge 22, defined as the distance
between points A and B (see FIG. 2). Malleable member 52 is
preferably constructed from an aluminum-alloy strip with a
rectangular cross-section, but may also be a moldable or malleable
metal or plastic member. Desirably, strip 52 is located between
layers 60, 62, and may be held in position by adhesive, or by a
border that is stitched or heat sealed to closely surround strip 52
to prevent slippage. Malleable strip 52 may be used in any
embodiment of the present invention.
[0054] The present invention may further include devices for
attaching mask 10 to the face of the wearer. Any type of
conventional attachment devices are within the scope and spirit of
the invention. For example, the mask 10 may include at least one
strap for securing about the wearer's head. Alternatively, the mask
may include straps extending from the top and bottom edges thereof
for being tied around the wearer's head (not shown). In an
alternative embodiment, the mask may include loops for being fitted
over the ears of a wearer (not shown). A vast number of attaching
devices are well known to those skilled in the art and any manner
of such device may be incorporated in the present invention. It
should be appreciated that a number of configurations and
alternative embodiments may be employed in the present invention,
and that the invention is not limited to any particular type of
attachment method to the face of the wearer. It is most desirable
that the attaching device allows a wearer to place the respirator
10 onto the wearer in a manner that no gapping between the wearer's
face and the periphery 16 occurs accidentally.
[0055] In one exemplary embodiment of the present invention, a
simple headband attachment device is a strap 42, and one of the
ways to adjustably connect the headband strap 42 to a respirator 10
is through an aperture such as a slit 44. However, it is
contemplated that additional clips, snaps, loops, hook and loop,
buttons, or other mechanical fasteners may be used to selectively
and/or adjustably attach a headband straps 42 to respirator 10. For
some applications, headband straps 42 are preferably constructed
from resilient polyurethane, but may be constructed from elastic
rubber or a covered stretch yarn. The covered stretch yarn may
consist of an elastomeric material wrapped with nylon or polyester.
For other applications, headband straps 42 may be double knitted
headbands such as circle knitted polyester/LYCRA or nylon/LYCRA.
Any flexible strip that is tolerated by the wearer may be used as a
strap.
[0056] The assembly of mask 10 is as follows. Filter body 12 may be
formed by cutting and connecting layers 60, 62 and optional middle
layer (or other layers) to each other along margins adjacent the
periphery 16. Such connections are preferably provided along top
edge 22 and side edges 24, respectively. Referring to FIG. 1, the
corresponding margins 65 may be formed by sewing, glue, heat
sealing, welding, thermal point bonding, ultrasonic bonding and/or
any other suitable connection procedure. In addition, a margin 67
may surround slit 33 for structural reinforcement. After the
margins are formed on the filter body, the body-facing surface of
the mask may be brought together by folding the blank about fold
line 18.
[0057] The stretch-panel edges 25' are aligned with the filter body
edges 25 and bonded together to form outwardly facing fin seams 71.
The edges 26 may be further be bonded together in a like manner to
create an outwardly facing fin seam 73. The junction between seams
71 and 73 is bonded to prevent air leakage. Top edge 22, side edge
24, and exposed edge 28 of the stretch-panel 14A cooperate with
each other to define the periphery 16 at the opening 11 of mask
10.
[0058] Desirably, each of the bonded seams 71, 73 share the
characteristic of being air impermeable. Thought it is contemplated
that lap seams or other connection methods may be used. It is most
desirable that seams 71 and 73 be created via an air impermeable
bond such as a pressure or ultrasonic bond.
[0059] A second exemplary embodiment of the respirator 10, shown in
FIG. 6, has not one, but two stretch-panels 14, designated as
"14B." Of course, more than two stretch-panels may make up the
overall surface area of mask 10. However, if stretch-panel 14 is
air impermeable, it may not be desirable to incorporate too much
stretch-panel material into the mask configuration as the mask 10
breathability could be compromised.
[0060] The shape of filter body 12 differs from that shown in FIG.
2 in that it is larger. The filter body 12 is symmetric about the
fold line 18. Because there is no stretch-panel 14A located under
the chin, the seam edges 26 extend all the way to edges 24. Seam
edges 26 extend between points "C" and "E." A fin seam 73 (or other
seam type mentioned previously) formed by connecting the seam edges
26 together. Desirably, fin seam 73 is air impermeable as in the
previous embodiment.
[0061] As described above, stretch-panels 14B may be triangular as
shown, or the other various shapes mentioned. Desirably, each
stretch-panel is located over the wearer's cheeks in a symmetric
configuration. In the embodiment of FIG. 6, each stretch-panel 14B
is located between the headband structure, tab 27 at about point
"D" and the end of seam 26 at point "C." The stretch-panel 14B has
an edge 28 that is shorter in length than the distance 80 between
points "C" and "D." Desirably, the length 82 of edge 28 is between
about 0.2 to about 0.33 the length of distance 80. More desirably,
length 82 is less than about 0.25 to about 0.5 of the length of
distance 80.
[0062] Referring now to FIG. 8, the side panels 14B may be
positioned to coincide with the tab member 27, and may have strap
42 or another headband attachment device connected thereto.
[0063] Referring to FIGS. 9 and 10, the panels 14B as shown in
FIGS. 6 and 8 may be elongated and meet at the edge 26. It is
further contemplated in these embodiments; the stretch-panels 14B
may be clear or translucent so that one may be able to see the
wearer's mouth.
[0064] Desirably, in the embodiments shown in FIGS. 6-10, like
seams 71 of the first embodiment, seams 77 are outwardly facing fin
seams created by an air impermeable bond such as a pressure or
ultrasonic bond.
[0065] It is further contemplated that a direction of stretch may
coincide with the anticipated movement of the wearer. For instance,
chewing may cause the wearer's jaw to move in direction 84 (see
FIG. 6). Thus, the stretch direction of panel 14B may substantially
align with direction 84. So as not to "lock up" the stretchability
of panel 14B, the periphery may also be configured to align with
the anticipated direction of movement.
[0066] The embodiment of respirator 10 as shown in FIG. 7 differs
from the previous embodiment in that an exhalation attachment
device 100 replaces the slit 44 and strap 42 (described in the
embodiment of FIG. 1). This device 100 bypasses the filtration
media of the respirator during exhalation enabling faster expulsion
of the hot humid exhaled breath. This improves the comfort of the
respirator. Generally, vent 100 is defined by a vent body having a
fastening system attached thereto. The fastening system comprises
at least one pull-strap fastening component 102 being formed
integrally with a fastening component 104. Additional details
regarding the vent 100 are disclosed in U.S. patent application
Ser. No. 11/840,031, filed Aug. 16, 2007, and incorporated herein
to the extent it is consistent with the present invention. Other
applicable exhalation vents are shown and described in U.S. patent
application Ser. No. 11/840,046, filed Aug. 16, 2007, and
incorporated herein to the extent it is consistent with the present
invention.
[0067] Although only a few exemplary embodiments of this invention
have been described in detail above, those skilled in the art will
readily appreciate that many modifications are possible in the
exemplary embodiments without materially departing from the novel
teachings and advantages of this invention. The mask may be
configured as any number of conventional masks. For example, the
mask may be formed as a traditional molded cup or cone-shaped mask.
Various configurations and shapes of masks are well known to those
skilled in the art and any and all such conventional masks are
within the scope and spirit of the present invention.
* * * * *