CONFORMABLE FACE MASK
A face mask comprising an elastic sheet and a filtering web. The elastic sheet defines inner and outer surfaces, and an elongated shape. The elongated shape forms a central portion. A cut-out is formed through a thickness of the elastic sheet at the central portion. The filtering web forms at least one pleat, and is bonded to the outer surface of the elastic sheet along a bondline. The bondline borders a chamber region at least partially established by the filtering web, with the cut-out being fluidly open to the chamber region. When worn, the inner surface is placed against the user's face, and a mouth and a portion of the nose of the user is inserted through the at least one cut-out. In some embodiments, the filtering web forms two vertical pleats that are located at opposite sides of a centerline of the face mask.
Protective face masks are useful in a number of fields. In the health care field, a face mask may be useful for protecting both the patient and the health care provider from airborne pathogens or for preventing the transfer of pathogens that reside in the bodily fluids or other liquids. Wearing protective face masks may also be useful in many industrial settings.
Many protective face masks are constructed to have a front panel that covers the nose and mouth of a user and a securing device (e.g., manual tie straps) that can attach this front panel securely to the head of the user. Often, the front panel and the tie straps are created separately in separate processes and then attached to one another (e.g., using adhesives, staples, or other mechanical fasteners). Face masks constructed from separate parts that must be joined together suffer from disadvantages. The attachment point between the front panel and the tie strap may be broken, for example, by pulling on the tie strap. Also, the separate manufacturing processes of the separate parts and the subsequent joining steps may result in a process that is relatively costly and time consuming. Additionally, the attachment points may be sites of weakness in the face mask. For example, the attachment of the two parts may result in apertures in the face mask that allow for the transfer of pathogens to or from the wearer of the face mask.
So-called single piece face masks are known. In this type of face mask, the front panel is formed integrally with side panels that otherwise provide openings that are used to attach the face mask to the wearer. The front panel and the side panels may be die cut from a web of material and may be formed at the same time. Some of these masks are stretchable to achieve a better fit on the face of the wearer. However, a stretchable, single piece face mask may not have the filtering efficiencies desired for some applications. Moreover, additional components are often required (e.g., a metal nose piece) to achieve the desired fit with the particular wearer's face. As a point of reference, the nose root (or bridge) can vary widely in shape and size from person-to-person. Many existing surgical face masks require additional medical nose piece components in order to comply with the nose root of the particular wearer.
Reliable face masks and convenient manufacturing processes for making them continue to be desired.
SUMMARYSome aspects of the present disclosure relate to a face mask comprising an elastic sheet and a filtering web. The elastic sheet defines an inner surface, an outer surface, and an elongated shape. The elongated shape forms a central portion and opposing, first and second lateral end portions extending from opposite sides of the central portion, respectively. An aperture is formed in each of the first and second lateral end portions. Finally, at least one cut-out is formed through a thickness of the elastic sheet at the central portion. The filtering web forms at least one pleat, and is bonded to the outer surface of the elastic sheet along a perimeter bondline. The perimeter bondline borders a chamber region that is at least partially established by the filtering web, with the at least one cut-out being fluidly open to the chamber region. With this construction, the face mask is configured to provide a worn state in which the inner surface is placed against the user's face, and a mouth and a portion of the nose of the user passes through the at least one cut-out. In the worn state, portions of the inner surface of the elastic sheet contact the user's face to create a substantially continuous line of engagement circumscribing the chamber region, effectively sealing the chamber region relative to user's breathing passages, with the pleated filtering web able to expand in shape via the pleat(s) as the user exhales. In some embodiments, the filtering web forms two vertical pleats that are located at opposite sides of a centerline of the face mask. When the face mask is fastened to a user, the two vertical pleats facilitate compliance of the face mask with the user's nose root. In other embodiments, the cut-out is relatively large, and has a teardrop like-shape through which a user's mouth and portion of the nose readily pass. In other embodiments, slits or lines of perforations are utilized as the cut-out. In yet other embodiments, one or more flaps are provided by the face mask that promotes sealing or compliance with the user's facial anatomy. Regardless, a protection chamber for the mouth and nose of the wearer is created.
The term “nonwoven” as used in this disclosure when referring to a sheet or web means having a structure of individual fibers or threads that are interlaid, but not in an identifiable manner as in a knitted fabric. Nonwoven fabrics or webs can be formed from various processes such as meltblowing processes, spunbonding processing, spunlacing processes and bonded carded web processes.
The term “elastic” as used in this disclosure refers to any material, including a film, fiber, nonwoven web or combination thereof, which exhibits recovery from stretching or deformation.
One embodiment of a face mask 20 in accordance with principles of the present disclosure is shown in
With additional reference to
The elastic sheet 22 has, in some embodiments, an elongated shape generally defining a central portion 50 and first and second lateral end portions 52, 54 flanking the central portion 50 on opposite sides, respectively. The central portion 50 is configured for wearing over a mouth and at least a portion of a nose of a person, and the first and second lateral end portions 52, 54 are each configured to at least partially extend around opposite sides of a person's face in a manner facilitating engagement with an ear of a person. In the illustrated embodiment, the first lateral end portion 52 can be configured to extend around the left side of a person's face, and the second lateral end portion 54 can be configured to extend around the right side of a person's face. In some embodiments, the first lateral end portion 52 forms an aperture 60 that can be used to engage a person's ear, and the second lateral end portion 54 has an aperture 62 to engage the person's other ear. In other embodiments, punch-out members can be used instead of apertures 60, 62, and the punch-out portion of the punch-out member can be removed to form the corresponding aperture. In yet other embodiments described below, the lateral end portions 52, 54 can be omitted, and other user-engaging features provided.
As a point of reference, a perimeter of the elastic sheet 22 (and thus of the face mask 20) can inherently define an intended orientation for wearing by a user. For example, and with specific reference to
With the desired orientation of the face mask 20 when worn in mind, the cut-out 28 is formed through an entire thickness of the elastic sheet 22 and is located in the central portion 50. With this arrangement, the cut-out 28 is fluidly open to the chamber region 26 (
The shape-related features illustrated and described with respect to the cut-out 28 of
In another embodiment, elastic sheet 22″ incorporates a plurality of cut-outs 28″ as shown in
In yet other embodiments, and as illustrated for elastic sheet 22′″ of
Returning to
The elastic sheet 22 can have a color other than white or could have a pattern of multiple colors. In other embodiments, the elastic sheet 22 can be imparted with a graphic. The term “graphic” means any design, shape, pattern or picture that is visible on the face mask 20, and specifically includes text (e.g., including one or more alphanumeric symbol), pictorial images that include one or more pictures, and combinations thereof. Color patterns and/or graphics may provide enjoyment for the wearer, for example, when the wearer is a child.
In some embodiments, the central portion 50 and the first and second lateral end portions 52, 54 are formed from the same material and form a unitary structure. In other words, the central portion 50 and the first and second lateral end portions 52, 54 are not formed as three separate pieces that are subsequently joined together. Rather, the central portion 50 and the first and second lateral end portions 52, 54 form a continuous structure. Thus, while the central portion 50 may not be clearly demarcated in the elastic sheet 22 as a standalone structure, bonding of the filtering web 24 can be viewed as effectively defining a region of the central portion 50. Also, face masks according to and/or made according to the present disclosure typically have a flat (i.e., planar) shape when they are not being worn. The term “flat” means any of the multiple portions are substantially parallel (i.e., within 10, 7.5 or 5 degrees of parallel) to a plane defined by the elastic sheet 22. The term “flat” also means that the face masks disclosed herein typically do not have means (e.g., seals, seams or bonding) to urge the face mask as a whole into a bent or permanently curved or folded position.
The elastic sheet 22 is configured to stretch in one or more directions. In some embodiments, the elastic sheet 22 has elongation of at least 5 (in some embodiments, at least 10, 25, 40, 50, 75, or 100) percent and up to about 150, 200, 250, 300, 350, or 500 percent in at least one direction. The elongation in terms of percent stretch is [(the extended length−the initial length)/the initial length] multiplied by 100. For example, if a material having an initial length of 1 cm can be stretched 0.50 cm, that is to an extended length of 1.50 cm, the material can be said to have an elongation of 50 percent. In some embodiments, the elastic sheet 22 can stretch in both the transverse direction T and the longitudinal direction L. In some embodiments, all of the central portion 50 and lateral end portions 52, 54 can be stretched in one or more directions. The ability of the elastic sheet 22 to stretch in at least one of the transverse T or longitudinal L directions will typically allow for fuller coverage of the wearer's face and provide for more flexibility in accommodating variously sized faces of potential users. In particular, horizontal and vertical stretching in the central portion 50 will typically allow for better fitting on the face.
The elastic sheet 22 also exhibits recovery from stretching. Recovery refers to a contraction of a stretched material upon termination of biasing force following stretching of the material by application of the biasing force. For example, if a material having a relaxed, unbiased length of 1.0 cm is elongated 50 percent by stretching to a length of 1.5 cm and subsequently contracts to a length of 1.1 cm after release of the stretching force, the material would have recovered 80% (0.4 cm) of its elongation. The elastic sheet 22 can have a recovery of, for example, at least 25, 50, 60, 70, 75, or 80 percent.
In some embodiments, different segments of the central portion 50 may have different elongations in the same direction. For example, at the lower and upper edges 70, 72 along the central portion 50, the elongation may be up to 5 (in some embodiments 4, 3, 2, or 1) percent in the transverse direction T, while between the lower and upper edges 70, 72, the elongation may be greater than 5 and up to 15 (in some embodiments 14, 13, 12, 11, or 10) percent in the transverse direction T. In other embodiments, at the lower and upper edges 70, 72 along the central portion 50, the elongation may be up to 5 (in some embodiments 4, 3, 2, or 1) percent in the longitudinal direction L, while between the lower and upper edges 70, 72, the elongation may be at least 70 (in some embodiments, at least 75, 80, or 85) percent in the transverse direction T. Reduced elongation at the lower and upper edges 70, 72 may be useful, for example, for providing a good seal against the user's face. In some embodiments, the central portion 50 has elongation of less than 10 (in some embodiments, up to 7.5, 5, 2.5, or 2, or 1) percent in the transverse direction T. In some embodiments, the first lateral end portion 52 and the second lateral end portion 54 each have an elongation of at least 15 (in some embodiments, at least 20, 25, 30, 40, 50, 75, or 90 or 100) percent and up to about 500 (in some embodiments, up to 350, 300, 250, or 200) percent in at least one of the longitudinal direction L or transverse direction T. The amount of elongation in the central portion 50 can be controlled, for example, by the choice of materials, the extent of attachment of the filtering web 24 to the central portion 50, and other features provided by the filtering web 24. Limiting the elongation of the central portion 50 may allow for better filtration properties.
Various materials can be employed for the elastic sheet 22. For example, in some constructions, the elastic sheet 22 is an elastic nonwoven web. In some embodiments, the elastic nonwoven web or portion thereof comprises a spunbonded, meltblown, or spunlace nonwoven. The term “spunbonded” refers to small diameter fibers that 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. Spunbond fibers are generally continuous and have diameters generally greater than about 7 microns, more particularly, between about 10 and about 20 microns. The term “meltblown” refers to fibers formed by extruding a molten thermoplastic material through a plurality of fine, usually circular, die capillaries as molten threads or filaments into converging high velocity, usually hot, gas (e.g., air) streams which attenuate the filaments of molten thermoplastic material to reduce their diameter, which may be to microfiber diameter. Thereafter, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly dispersed meltblown fibers. Meltblown fibers are generally microfibers which may be continuous or discontinuous with diameters generally less than 10 microns. Spunlacing uses high-speed jets of water to strike a web to intermingle the fibers of the web. Spunlacing is also known as hydroentangling and can be carried out on fibrous webs made, for example, using carded webs and air-laid webs.
Exemplary useful materials for making the elastic nonwoven web or portion thereof (e.g., sheet) include thermoplastic elastomers such as ABA block copolymers, polyurethane elastomers, polyolefin elastomers (e.g., metallocene polyolefin elastomers), polyamide elastomers, ethylene vinyl acetate elastomers, and polyester elastomers. An ABA block copolymer elastomer generally is one where the A blocks are polystyrenic, and the B blocks are conjugated dienes (e.g., lower alkylene dienes). The A block is generally formed predominantly of substituted (e.g., alkylated) or unsubstituted styrenic moieties (e.g., polystyrene, poly(alphamethylstyrene), or poly(t-butylstyrene)), having an average molecular weight from about 4,000 to 50,000 grams per mole. The B block(s) is generally formed predominantly of conjugated dienes (e.g., isoprene, 1,3-butadiene, or ethylene-butylene monomers), which may be substituted or unsubstituted, and has an average molecular weight from about 5,000 to 500,000 grams per mole. The A and B blocks may be configured, for example, in linear, radial, or star configurations. An ABA block copolymer may contain multiple A and/or B blocks, which blocks may be made from the same or different monomers. A typical block copolymer is a linear ABA block copolymer, where the A blocks may be the same or different, or a block copolymer having more than three blocks, predominantly terminating with A blocks. Multi-block copolymers may contain, for example, a certain proportion of AB diblock copolymer, which tends to form a more tacky elastomeric film segment. In some embodiments, the elastic nonwoven sheet useful for practicing the present disclosure is made from a variety of useful materials (e.g., polypropylene, polypropylene-polyethylene copolymers, and thermoplastic polyurethanes). In some embodiments, the elastic nonwoven web is made, for example, from multi-component (e.g., bi-component such as core-sheath) fibers. In some embodiments, the elastic nonwoven web is a multi-layer laminate of different materials (e.g., the materials described above) in the layers. For example, the elastic nonwoven web may comprise a layer of meltblown fibers between two layers of spunbonded fibers.
Materials can be selected for the elastic nonwoven portion or sheet, for example, depending on how they feel against the skin. The elastic nonwoven sheet can be made from materials that feel soft against the skin. The elastic nonwoven sheet can also be made from materials that have a rubbery feeling so that they can stay in place.
Several materials useful for making the elastic nonwoven sheet are commercially available, for example, polyolefins from ExxonMobil, Houston, Tex., under the trade designation “VISTAMAXX” and thermoplastic polyurethane elastomers from Huntsman, The Woodlands, Tex., under the trade designation “IROGRAN”. In some embodiments, the elastic nonwoven sheet comprises a matrix nonwoven material. In some embodiments, the elastic nonwoven sheet comprises a spunbond nonwoven available from Idemitsu Kosan Co., Ltd., Tokyo, Japan, under the trade designation “STRAFLEX”. In other embodiments, the elastic sheet is a bicomponent elastic nonwoven web employing a styrenic block copolymer core material and a sheath material. For example, a bicomponent elastic nonwoven web of styrenic block copolymer core available from Kraton Polymers LLC, Houston, Tex. (under the trade designation G1643, MD6705, or MD6717) and a polypropylene sheath. The core:sheath radio can be 85:15 or 80:20, for example.
Filtering Web 24The filtering web 24 is bonded to the central portion 50 as described in greater detail below. The term “filtering” with respect to the filtering web 24 described herein refers to separating or removing a portion of the exhalation from the face mask wearer, or a portion of the inhalation encountered by the face mask wearer. The filtering web 24 is typically capable of at least one of providing a barrier to the transmission of pathogenic microorganisms to or from the wearer, trapping allergens (e.g., pollen), trapping particulates, trapping or masking odors, trapping or providing a barrier to liquids, removing cold air (i.e., providing thermal insulation), or reducing viral or bacterial contamination.
As shown in
The pleat 100 is arranged in the filtering web 24 such that upon final assembly of the filtering web 24 to the elastic sheet 22, the pleat 100 (or the fold lines 102, 104) extends substantially parallel (i.e., within 10 degrees of parallel) of the longitudinal direction L, and thus can be referred to as a vertical pleat (i.e., when the face mask 20 is worn by a user, the pleat 100 (as defined by a direction of the fold lines 102, 104) has a vertical orientation). While a single vertical pleat 100 is illustrated, in other embodiments, two vertical pleats can be provided. For example, with the alternative face mask 20′ of
In yet other embodiments, and with reference to
Returning to
In some embodiments, the filtering web 24 is useful, for example, for protecting the face mask wearer from unpleasant odors. In some of these embodiments, the filtering web 24 is loaded with activated carbon or other particles. In related embodiments, the filtering web 24 may include two or more layers of material, for example in the form of a pad. The filtering web 24 may also be a nonwoven web with the particles uniformly dispersed throughout the nonwoven web using conventional techniques. Or the filtering web 24 can be formed with the particles embedded in the nonwoven, for example an activated carbon fiber nonwoven available, for example from Kuraray Chemical Co., Osaka, Japan. In other embodiments, the filtering web 24 is provided with a fragrance (e.g., for masking the unpleasant odors).
In some embodiments, the filtering web 24 or portion thereof is a nonwoven web of microfibers that are thermally insulating. For example, the filtering web 24 may comprise a mixture of microfibers and crimped staple fibers as described in U.S. Pat. No. 4,118,531, the disclosure of which is incorporated herein by reference in its entirety. In some of these embodiments, the filtering web 24 can include two or more layers of material, for example in the form of a pad.
In yet other embodiments, the filtering web 24 includes an antiviral, antibacterial, or antifungal agent. Suitable agents of this type include citric acid, boric acid, and silver oxide. In some of the embodiments, the filtering web 24 comprises a nonwoven web onto which the antiviral, antibacterial, or antifungal agent is applied (e.g., by rolling or spraying as described, for example, in U.S. Pat. No. 4,856,509). The antiviral, antibacterial or antifungal agents may be used for killing airborne pathogens and for pathogens in bodily fluids or other liquids that may come into contact with the face mask.
In yet other embodiments, the filtering web 24 or a portion thereof is microfiber insulation available from 3M Company, St. Paul, Minn., under the trade designation “THINSULATE”.
In some embodiments, the filtering web 24 or portions thereof provides a barrier to liquids, for example by virtue of having a low-surface-energy coating, on at least one surface, or a low-surface-energy material embedded in the web. The low-surface-energy coating or material can be provided, for example, with a wax, a silicone, or fluorochemical additive. Suitable fluorochemical additives include those described in U.S. Pat. Nos. 5,025,052; 5,099,026; 5,706,804; and 6,127,485. Filtering webs providing a barrier to liquids (i.e., fluid resistance) may be useful, for example, for a surgical mask. While some filtering web constructions can be designed to exhibit multiple functions, face masks according to the present disclosure may include two different filtering web portions, with each filtering web portion having the same or different functionality. For example, the face mask may include both a first filtering web portion that is charged to remove particles and a second filtering web portion that is designed to provide thermal insulation. Combinations of any of the functionalities as described can be employed. To make face masks according to these embodiments, two different filtering web portions with the desired functionality are used, and combine to define the filtering web 24.
Elastic sheet 22/Filtering Web 24 Bonding
Regardless of the materials employed for the elastic sheet 22 and the filtering web 24, the filtering web 24 is bonded, either directly or indirectly, to the outer surface 40 of the elastic sheet 22 along a perimeter bondline 122. As best shown in
With specific reference to
Returning to
Once the face mask 20′ is applied to the wearer, the pleats 110, 112 (or any of the other pleat configurations described above) can freely expand as necessary to accommodate contours of the user's face 166, as well as inhaled and exhaled breaths.
Enhanced ContactAnother embodiment face mask 180 in accordance with principles of the present disclosure is shown in
Another embodiment face mask 200 in accordance with principles of the present disclosure is shown in
Another embodiment face mask 220 in accordance with principles of the present disclosure is shown in
Some methods of making a face mask according to the present disclosure involves bonding a filtering web and optionally a second web to a central lane of an elastic web (e.g., an elastic nonwoven web) to form a layered web, and subsequently stamping a face mask into the layered web. With these optional techniques, a plurality of face mask can be manufactured on a continuous basis, and can be temporarily maintained with one another in roll form. The layered web may be of any size, and the face mask may be stamped therefrom in any number, shape, or size.
A schematic illustration of an embodiment of a method of making a face mask according to the present disclosure is illustrated in
For a face mask according to and/or made according to the present disclosure, the first lateral end portion, the second lateral portion, and the central portion of the elastic sheet may all be integrally formed with one another and stamped from the continuous elastic web in one piece. Stamping includes cutting the layered web, for example, with continuous cuts or with discontinuous cuts (e.g., perforations). The cuts (e.g., continuous or discontinuous cuts) may be made, for example, using die cutting (e.g., rotary die cutting) or laser cutting. Referring again to
The continuous web manufacturing of the plurality of face masks described above is advantageous in that separate manufacturing steps are reduced or eliminated. Continuous web manufacturing is possible because the central portion 50 and first and second lateral end portions 52, 54 can be formed simultaneously during the stamping process. Furthermore, the configuration of the face mask is such that a filtering web, and elastic nonwoven web, and an optional second web that are continuous in the machine direction may be used.
A plurality of the face masks according to and/or made according to the present disclosure can be formed or provided as a roll of face masks 300 as shown
In the illustrated embodiment, the roll 300 is formed around a core. In some embodiments, the continuous layered web is formed into a roll without a core, and the face masks can be dispensed from inside the roll, for example, from a dispenser in the general form of a canister. For the continuous layered web according to the present disclosure, the plurality of face masks may be stamped into the continuous web 304 but not removed from the continuous web 304 so that the web may be formed, for example, into a roll or otherwise dispensed from the continuous web 304. The solid lines shown in
Regardless of whether the plurality of face masks are temporarily maintained in a roll,
Another embodiment face mask 400 in accordance with principles of the present disclosure is shown in
The filtering web 24 can have any of the forms described above, and is assembled to the elastic sheet 402 as previously described. The loops 404, 406 can be strips of conformable material (e.g., elastic straps, fabric, etc.), and are attached to a corresponding one of the side edges 408, 410. For example, the first loop 404 extends between opposing ends 414, 416. The ends 414, 416 are attached (e.g., bonded, welded, mechanically fastened, etc.) to at least one of the elastic sheet 402 and the filtering web 24 at or adjacent the first side edge 408 in a spaced apart fashion. The second loop 406 is similarly attached to at least one of the elastic sheet 402 and the filtering web 24 at or adjacent the second side edge 410. With this construction, the loops 404, 406 are available for engaging a wearer's ears and thus serve as earloops.
A related embodiment face mask 400′ is shown in
Another embodiment face mask 450 in accordance with principles of the present disclosure is shown in
Face masks, and related methods of use and making thereof, of the present disclosure provide a marked improvement over previous designs. The single piece, elastic sheet in combination with a pleated, outside-facing filtering web advantageously conforms or complies with contours of a wearer's face with a construction that is highly cost effective to manufacture. The cut-out(s) formed in the elastic sheet promote straight forward placement of the wearer's breathing passages with the chamber region of the face mask, with the optional vertical pleats enhancing conformance to a variety differently-shaped nose roots.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the present invention.
Claims
1. A face mask comprising:
- an elastic sheet defining: an inner surface, an outer surface, an elongated shape forming a central portion and opposing first and second lateral end portions extending from opposite sides, respectively, of the central portion, a first aperture in the first lateral end portion, a second aperture in the second lateral end portion, at least one cut-out through a thickness of the elastic sheet in the central portion;
- a filtering web forming at least one pleat, the filtering web being bonded to the outer surface of the elastic sheet along a perimeter bondline;
- wherein a chamber region is at least partially established by the filtering web and is bordered by the perimeter bondline;
- and further wherein the at least one cut-out is fluidly open to the chamber region.
2. The face mask of claim 1, wherein the face mask is configured to provide a worn state in which the inner surface is placed against the user's face, and a mouth and at least a portion of a nose of the user are inserted through the at least one cut-out.
3. The face mask of claim 2, wherein the face mask is configured to form a substantially continuous line of contact with a user's face in the worn state that circumscribes the chamber region.
4. The face mask of claim 1, wherein the elongated shape of the elastic sheet in a flattened state defines a transverse direction generally extending between the first and second apertures, and a longitudinal direction perpendicular to the transverse direction, and further wherein the at least one pleat includes a first vertical pleat having a fold line substantially parallel to the longitudinal direction.
5. The face mask of claim 4, wherein the fold line runs continuously from a first location at the perimeter bondline to a second location on the perimeter bondline opposite the first location.
6. The face mask of claim 4, wherein the at least one pleat includes a second vertical pleat having a fold line substantially parallel to the longitudinal direction.
7. The face mask of claim 6, wherein the elongated shape defines a centerline in the longitudinal direction and bi-secting the central portion, and further wherein the first and second vertical pleats are located at opposite sides of the centerline.
8. The face mask of claim 6, wherein the first and second vertical pleats are configured to cause the elastic sheet to comply with contours of a user's nose root region in the worn state.
9. The face mask of claim 1, wherein the elongated shape of the elastic sheet in a flattened state defines a transverse direction generally extending between the first and second apertures, and a longitudinal direction perpendicular to the transverse direction, and further wherein the at least one pleat includes a horizontal pleat having a fold line substantially parallel to the transverse direction.
10. The face mask of claim 9, wherein the at least one pleat includes a second horizontal pleat having a fold line substantially parallel to the transverse direction.
11. The face mask of claim 9, wherein the at least one pleat includes a first vertical pleat having a fold line substantially parallel to the longitudinal direction.
12. The face mask of claim 1, wherein the elongated shape of the elastic sheet in a flattened state defines a transverse direction generally extending between the first and second apertures, a longitudinal direction perpendicular to the transverse direction, and a centerline in the vertical longitudinal and bi-secting the central portion, and further wherein an edge of the face mask tapers in height from the centerline toward the first and second lateral end portions.
13. The face mask of claim 1, wherein the elastic sheet includes an elastic nonwoven web.
14. The face mask of claim 3, wherein the elastic sheet further includes a polymeric film laminated to the elastic nonwoven web, and further wherein the filtering web is bonded to the polymeric film.
15. The face mask of claim 1, wherein the filtering web includes a filtering layer and a polymeric film layer, and further wherein the polymeric film layer faces the outer surface of the elastic sheet.
16. The face mask of claim 1, wherein the at least one cut-out is an oblong shape.
17. The face mask of claim 1, wherein the at least one cut-out includes a plurality of slits.
18. The face mask of claim 17, wherein the plurality of slits includes first and second slits forming an X shape.
19. The face mask of claim 1, wherein at least one of the elastic sheet and the filtering web forms a flap configured to be folded toward the inner surface and contact a user's face.
20. A method of using a face mask, the method comprising:
- receiving a face mask including: an elastic sheet defining: an inner surface, an outer surface, an elongated shape forming a central portion and opposing first and second lateral end portions extending from opposite sides, respectively, of the central portion, a first aperture in the first lateral end portion, a second aperture in the second lateral end portion, at least one cut-out through a thickness of the elastic sheet in the central portion, a filtering web forming at least one pleat, the filtering web being bonded to the outer surface of the elastic sheet along a perimeter bondline, wherein a chamber region is at least partially established by the filtering web and is bordered by the perimeter bondline, and further wherein the at least one cut-out is fluidly open to the chamber region;
- fastening the face mask to a user's head, including: placing the first and second apertures over ears of the user, respectively, inserting a mouth and nose region of the user's head through the cut-out, forming a substantially continuous line of contact between a face of the user and the inner surface, the line of contact circumscribing the chamber region; and
- expanding the at least one pleat in response to an exhaled breath of the user.
21. A method of claim 20, wherein the step of fastening the face mask further includes a region of the inner surface conforming to a shape of a user's face in a vicinity of the user's nose root.
Type: Application
Filed: Feb 25, 2013
Publication Date: Jun 25, 2015
Inventor: Alexander C. Tsuei (Woodbury, MN)
Application Number: 14/408,910