Respiratory protection device and method of manufacturing the same

Abstract

A disposable respirator includes a pleated media layer. The pleated media includes a first series of substantially parallel unbonded elastic material between a first nonwoven porous web and a second nonwoven porous web. The first nonwoven porous web is directly bonded to the second nonwoven porous web. At least a portion of the pleated media is elastically extensible under tension. The respirator further includes a fit feature that includes the pleated media.

Description

Technical Field

[0001] Breathing devices with pleated, expandable filter media are used as facial seals and / or nose pads, enhancing wearer fit and comfort. These devices offer flexibility, low pressure drop, and high particulate loading capacity, reducing breathing resistance and providing enhanced comfort and fit for the wearer. Summary of the Invention

[0002] The aim is to improve the fit, comfort, and performance of respiratory protective devices.

[0003] The present invention provides a disposable respirator comprising a wrinkled medium layer. The wrinkled medium comprises a first series of substantially parallel, non-bonded elastic materials between a first nonwoven porous mesh and a second nonwoven porous mesh. The first nonwoven porous mesh is directly bonded to the second nonwoven porous mesh. At least a portion of the wrinkled medium is elastically stretchable under tension. The respirator also includes a fitting feature comprising the wrinkled medium.

[0004] The above description is not intended to illustrate every embodiment. Details of one or more embodiments of the invention are also set forth in the following detailed description. Other features, objectives, and advantages will become apparent from this specification and the claims. Attached Figure Description

[0005] Figure 1 This is a schematic diagram showing a pleated filter medium that can be used in the embodiments described herein.

[0006] Figure 2 This is a schematic cross-sectional view of the pleated filter media, showing its structure.

[0007] Figure 3 This is a schematic diagram of manufacturing a pleated filter media according to one embodiment of the present disclosure.

[0008] Figures 4A to 4D An example of a cup-shaped respirator with a nasal pad according to an embodiment of this document is illustrated.

[0009] Figures 5A to 5D An example of a horizontal three-fold respirator with a nasal pad according to an embodiment of this article is shown.

[0010] Figures 6A to 6D An example of a nose pad according to the embodiment described herein is shown.

[0011] Figures 7A to 7K Examples of cup-shaped respirators with and without facial seals according to embodiments of this document are illustrated.

[0012] Figure 8An example is illustrated of a method for forming a respirator with fitting features according to an embodiment of this article.

[0013] Figures 9A to 9B An example is given comparing the internal temperatures of respirators with different surface areas.

[0014] It should be understood that those skilled in the art can devise many other modifications and embodiments that fall within the scope and spirit of the principles of this disclosure. The illustrations may not be drawn to scale. Detailed Implementation

[0015] As used herein, the terms “an,” “a,” and “the” are used interchangeably and refer to one or more; and “and / or” is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0016] Furthermore, in this document, the ranges expressed by the endpoints include all numbers contained within that range (e.g., 1 to 10 includes 1.4, 1.9, 2.33, 5.75, 9.98, etc.).

[0017] Furthermore, in this document, the expression "at least one" includes all numbers that are one or greater than one (e.g., at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.).

[0018] As used in this article, "containing at least one of A, B, and C" means containing only element A, containing only element B, containing only element C, containing both A and B, containing both A and C, containing both B and C, and combinations containing all three.

[0019] As used herein, the term "respirator" refers to a close-fitting face covering that filters particles and droplets from inhaled and exhaled air. As described herein, respirators can be designed to seal against the user's face along a continuous, sealed perimeter (often referred to as a "runway"). This feature distinguishes respirators from cloth masks, surgical masks, and the like. In some embodiments, the respirator described herein contains charged fibers to attract particles, thereby increasing load capacity.

[0020] Disposable respirators are used in a variety of environments and industries. They were ubiquitous at the height of the COVID-19 pandemic, and come in a variety of brands and models. They can be discarded after a single use, or after a day, a week, or even longer. Some obstacles to the use and compliance of disposable respirators include user comfort and respirator fit when wearing the device.

[0021] Many different configurations of disposable respirators exist on the market. However, the vast majority of them have a fixed shape and size that cannot be stretched to accommodate the wearer's facial movements, such as yawning, laughing, or talking. In some cases, the respirator may slip or move with the wearer's facial movements, resulting in poor fit, leakage, or even scratches. Some respirator designs that offer stretch flexibility involve bulky plastic structures that can be heavy, or have limited stretchability and additional filter media. Implementations described herein feature flexible, stretchable, and resilient fit characteristics that can be used with a variety of respirator models. Such fit characteristics can help allow different respirator models to accommodate a wider range of facial sizes, potentially increasing respirator compliance in the workplace.

[0022] Respirator fit also involves whether the respirator seals adequately against the wearer's face. An example area of ​​concern is the bridge of the nose. Nose pads have been described in PCT Publication WO 2022 / 235472, published November 10, 2022, and in US PAP 2008 / 0099022, published May 1, 2008. However, the described nose pads are not stretchable. US Patent 10,136,687, published November 27, 2018, describes a nasal notch or cavity area that receives the user's nose, but is limited to a single, fixed shape and therefore only contributes to a limited range of nasal bridge height and width.

[0023] PCT publication WO 2014 / 110075, published on July 17, 2014, describes a face seal, but the face seal is not stretchable and is not formed of a filter material.

[0024] The desired respirator fit feature improves the fit of the disposable respirator to the wearer and increases the fit range for facial size and contour—for example, the fit feature described herein improves the fit of the respirator to an individual and increases the number of individuals to whom the respirator can be used.

[0025] As described, for example, in U.S. Provisional Patent Applications 63 / 496,002 and 63 / 496,003, both filed April 13, 2023, the use of pleated media in respirators provides a larger surface area than flat sheet media while maintaining a more compact or lower profile than pleats with good conformability.

[0026] As used herein, the term "pleated medium" refers to a type of functional medium laminate that has optional mesh support throughout the respirator design. The functionality of pleated medium is described in more detail in the Embodiments section of U.S. Provisional Patent Application 63 / 434365, filed December 21, 2022, which is incorporated herein by reference. The terms "pleated medium" and "pleated medium" are used interchangeably herein.

[0027] The embodiments described herein use a pleated medium to form a fit feature that improves the fit of a disposable respirator. The fit feature of this invention exhibits tensile strength and tensile elasticity. The fit feature of this invention can increase the fit and / or comfort of the respirator. The fit feature of this invention can be incorporated into the respirator during the respirator manufacturing process, potentially without adding a rate-limiting transition step.

[0028] In some embodiments, the fit feature includes a nose pad that allows for active stretching and contraction as the wearer's face and head move, thereby maintaining contact and a good seal. The nose pads in the embodiments described herein are formed of a filter medium having the same or higher filtration performance as the respirator body, such that aerosol penetration will not reduce the efficiency rating of the FFR. The nose pads in the embodiments described herein exhibit low contact pressure, thereby increasing user comfort.

[0029] Traditional nose pads are typically supplied in roll form for application in the machine direction or transverse machine direction. The number of splices (e.g., joining foam lengths to form a longer length) is limited, which affects manufacturing productivity. Pleated media are self-supporting and provide the required compliance to ensure a fit around the nose, thus allowing for the application of splice-free, continuous lengths.

[0030] In some embodiments, the fit feature includes a face seal made of a pleated medium having low contact pressure and the same or higher filtration performance as the medium used for the respirator body. The face seal described herein actively stretches and acts as a “spacer” to help the respirator better fit narrower or shorter faces. The stretchability and elasticity of the face seal described herein help maintain a fit during the wearer’s facial and head movements. The face seal described herein can be manufactured to fit any respirator style, shape, or size—such as a cup style, a vertically folded style, a horizontally folded style, etc.

[0031] Some embodiments described herein include an adhesive feature formed from materials selected for sustainability and / or recyclability. Existing respirator constructions typically utilize polyurethane foam, which crosslinks during formation to maintain the structure. In some embodiments, the adhesive feature described herein is formed from a remeltable material.

[0032] Figure 1 The image shown is a top view of an exemplary embodiment of the pleated filter media of this disclosure. The pleated filter media 10 includes a plurality of spaced-apart elastic filaments. The plurality of elastic filaments are sandwiched between two nonwoven porous fiber webs. During the manufacture of the pleated filter media (referred to herein as "pleated media"), the elastic filaments are stretched under tension such that when the tension is released, the nonwoven porous fiber webs become pleated. Figure 2 The image shown is a side view of the filter medium 20, which shows a first nonwoven porous fiber web 24 and a second nonwoven porous fiber web 26, with elastic filaments 22 positioned between them. Figure 2 The diagram shows a first nonwoven porous fiber web 24 in direct contact with a second nonwoven porous fiber web 26. Based on the resulting article, it is believed that when an adhesive is used, the two nonwoven porous fiber webs bond together with the filaments between them. It is assumed that the bonding of the first and second nonwoven porous fiber webs is discontinuous, and that the nonwoven porous fiber webs may not be bonded to the filaments along their entire length (e.g., by adhesive).

[0033] Material List - Nonwoven Media

[0034] Table 1 lists the nonwoven webs used to manufacture pleated media as described in U.S. Provisional Patent Application 63 / 434365, filed December 21, 2022, and Table 2 lists their initial pressure drop (dP) and permeability in NaCl and DOP tests.

[0035] The effective fiber diameter (EFD) can be estimated by using the method shown in CN Davies, Air Filtration (Academic, London, 1973), by measuring the pressure drop through a filter of known material.

[0036]

[0037] As described in U.S. Provisional Patent Application 63 / 434365, filed December 21, 2022, the media network in Table 1 is corrugated. Table 2 lists the initial pressure drop and permeability of the networks that include the media listed in Tables 1 and 2.

[0038] Table 2. Initial dP and permeability of flat and wrinkled nets in NaCl test

[0039] The elastic filaments or elastic fibers of this application (which may comprise one or more elastic filaments) include copolymers and are elastic in nature, meaning that the fibers are capable of recovering or at least partially recovering their length after being stretched.

[0040] As used herein, the term "fiber" refers to a plurality of "filaments" joined together. It should be noted that while a term may be used relative to a particular embodiment, embodiments herein may use a single elastic filament or a plurality of elastic filaments joined together to form an elastic fiber.

[0041] An example of an elastic fiber roll may be traded under the name "100% Lycra Spandex 235 Multifil", DTEX737, 210 denier, obtained from Invista Company, Wichita, Kansas. Another example of an elastic filament is made from a propylene-ethylene copolymer with a density of 0.85-0.9 g / cc. Exemplary types of polymeric materials that can be used for the filaments of this application include: natural rubber, synthetic rubber, polyether-polyurethane, polyamide, polyisoprene, copolymers of isoprene and chloroprene rubber, polymers of 2-chloro-1,3-butadiene, polyether-polyurea copolymers (e.g., synthetic elastic fiber (Lycra)), and polyurethane (e.g., spandex). Other examples include Kraton. ™ Copolymers. These are elastic triblock polymers comprising high-Tg end blocks made of polystyrene and low-Tg center blocks made of one or more isoprene, butadiene, etc.

[0042] In one embodiment, the filament or fiber has a diameter of at least 1 micrometer, 5 micrometers, 10 micrometers, or even 20 micrometers, and at most 25 micrometers, 50 micrometers, 100 micrometers, 200 micrometers, 400 micrometers, 600 micrometers, 800 micrometers, 1000 micrometers, or 1200 micrometers. In one embodiment, the filament has a denier of at least 100, 150, 175, 200, 210, 220, 250, or even 500. In one embodiment, the filament has a denier of at most 1200, 900, 800, 700, 600, 500, 400, 350, 300, 250, or even 225.

[0043] Nonwoven porous fiber web

[0044] Elastic fibers or filaments are positioned between two nonwoven porous fiber webs (referred to herein as nonwoven webs). For example, the nonwoven webs of this disclosure can be manufactured by wet web forming, carding web forming, air-blowing web forming, jet web forming, spunbond, meltblown, or a combination thereof. The nonwoven webs of this disclosure can also be formed from fibrillated membrane fibers. The nonwoven webs of this disclosure can also be formed from fibrillated membranes (e.g., fibrillated membranes as described in U.S. Patent RE32171, published June 3, 1986).

[0045] In some embodiments, the nonwoven web may undergo a re-fluffing step after formation to increase its bulk. The nonwoven web may also comprise, or be composed of, a loose fabric or a knotted web. The nonwoven web may include nanofibers produced by methods such as electrospinning. Spunbond fibers are formed by extruding molten thermoplastic polymers as filaments through multiple fine, typically circular capillaries via a spinneret, wherein the diameter of the extruded fibers decreases rapidly. Meltblown fibers are typically formed by extruding molten thermoplastic material as molten threads or filaments into a high-speed, typically heated gas (e.g., air) stream through multiple fine, typically circular die capillaries, which thins the molten thermoplastic material filaments to reduce their diameter. Subsequently, the meltblown fibers are transported by the high-speed gas stream and deposited on a collecting surface to form randomly dispersed meltblown fibers. Any of these nonwoven webs may be made from a single type of fiber or two or more fibers that differ in type and / or thickness of thermoplastic polymer.

[0046] Suitable thermoplastic polymer materials include, but are not limited to, polyolefins (such as polypropylene or polyethylene), poly(isoprene), poly(butadiene), chlorinated polymers, polyamides, polyimides, polyethers, poly(ether sulfone), poly(sulfone), poly(vinyl acetate), polyesters such as poly(lactic acid), copolymers of vinyl acetate, such as poly(ethylene)-co-poly(vinyl alcohol), poly(phosphazene), poly(vinyl ester), poly(vinyl ether), poly(vinyl alcohol), and poly(carbonate).

[0047] Suitable polyolefins include, but are not limited to, poly(ethylene), poly(propylene), poly(1-butene), poly-4-methyl-1-butene, copolymers of ethylene and propylene, α-olefin copolymers (such as copolymers of ethylene or propylene with 1-butene, 1-hexene, 1-octene and 1-decene), poly(ethylene-co-1-butene), and poly(ethylene-co-1-butene-co-1-hexene).

[0048] Suitable polyamides include, but are not limited to, typical nylon polymers such as poly(iminoadiminohexamethylene), poly(iminoadiminodecamethylene), and polycaprolactam. Suitable polyimides include, but are not limited to, poly(pyromellitictetramethylene).

[0049] Suitable poly(ether sulfone) includes, but is not limited to, poly(diphenyl ether sulfone) and poly(diphenyl sulfone-co-diphenyl sulfone oxide).

[0050] Suitable vinyl acetate copolymers include, but are not limited to, poly(ethylene-co-vinyl acetate) and those copolymers in which at least some of the acetate groups have been hydrolyzed to provide a variety of poly(vinyl alcohols).

[0051] The fibers selected for nonwoven webs depend on the type of particles to be filtered. Particularly useful fibers include meltblown fiber webs, such as those disclosed in Wente, Van A.'s "Superfine Thermoplastic Fibers" (Industrial Engineering Chemistry, Vol. 48, p. 1342 and later (1956)). Meltblown fiber webs provide a particularly good filtration layer when used in a persistently charged form (see U.S. Patent No. 4,215,682 to Kubik et al.). Preferably, these meltblown fibers are microfibers having an effective diameter of at least 4 micrometers, 6 micrometers, 8 micrometers, or even 10 micrometers, and at most 12 micrometers, 14 micrometers, 16 micrometers, or even 20 micrometers. Other particularly useful filtration fibers are charged fibrillated membrane fibers, such as those disclosed in U.S. Patent RE 31,285 to Van Turnhout. Rosin wool fiber webs and glass fiber webs are also useful, as are solution-spun fibers or electrostatically sprayed fibers, especially fibers that exist in the form of microfibers.

[0052] Nonwoven webs are porous, meaning that the outer surface of one side of the nonwoven web is in fluid communication with the outer surface of the opposite side of the same nonwoven web. This ensures the flow of steam, air, or liquid through the nonwoven web. Nonwoven webs are co-extruded, meaning that the web is a single, continuous layer of nonwoven material without cracks or tears.

[0053] In one embodiment, at least one nonwoven web of the present disclosure comprises electret fibers. An electret is a dielectric material having a semi-permanent charge or dipole polarization. Electrets are typically improved by incorporating charging additives into a polymer material and then inducing charge onto the polymer material using corona treatment, triboelectric charging treatment, water charging treatment, or combinations thereof. In one embodiment, the electret fiber is a monocomponent fiber. In another embodiment, the electret fiber is a bicomponent fiber, such as a core-sheath fiber, side-by-side fibers, etc. In one embodiment, the electret fiber is a core-sheath fiber comprising a core having a co-elongated sheath disposed thereon. In one embodiment, the core comprises a charge-reinforcing additive. In one embodiment, the sheath comprises a charge-reinforcing additive. In one embodiment, the electret fiber is a side-by-side fiber, wherein the fiber comprises two components adjacent to each other along the length of the fiber. In one embodiment, the electret fiber is a so-called "island-type" extruder, wherein multiple fiber cores (i.e., more than one, two, four, or even six cores) are distributed within a polymer matrix, which also forms a sheath.

[0054] Many charge-enhancing additives for manufacturing electret-containing fiber webs are known in the art. Exemplary charge-enhancing additives may include pigments, light stabilizers, primary and secondary antioxidants, metal passivators, hindered amines, hindered phenols, metal salts, triphosphites, phosphates, and combinations thereof. Preferably, the charge-enhancing additive is solid under ambient conditions to prevent migration within the resin and does not decompose at moderate temperatures. In one embodiment, the charge-enhancing additive is solid at temperatures of at least 25°C, 30°C, 40°C, 50°C, 60°C, 80°C, or even 100°C. In one embodiment, the charge-enhancing additive does not decompose, for example, when measured by thermogravimetric analysis at a heating rate of 10°C / min to 235°C under nitrogen, there is no significant weight loss (i.e., less than 5 wt%, 1 wt%, or even 0.1 wt%).

[0055] Particularly preferred charge-enhancing additives include hindered amine-based additives, triazine-based additives, and hindered phenol-based additives.

[0056] Specific examples of additives based on hindered amines or triazines include: (poly[[6-(l,l,3,3-tetramethylbutyl)amino]-s-triazine-2,4-diyl][[(2,2,6,6-tetramethyl-4-piperidinyl)imino]hexamethylene[(2,2,6,6-tetramethyl-4-piperidinyl)imino]]), which is available under the trade name "CHIMASSORB 944" from BASF, Ludwigshafen, Germany; dimethyl succinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidin condensate, which is available under the trade name "TINUVIN 622" from BASF; di-tert-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentamethyl-4-piperidinyl), which is available under the trade name "TINUVIN 144” is available from BASF; condensation polymers of dibutylamine-1,3,5-triazine-N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl-1,6-hexamethylenediamine-N-(2,2,6,6-tetramethyl-4-piperidinyl)butylamine, which are available from BASF under the trade name “CHIMASSORB 2020”; 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-((hexyl)oxy)-phenol, which are available from BASF under the trade name “TINUVIN 1577”; N-substituted amino aromatic compounds, particularly triamino-substituted compounds, such as 2,4,6-triphenylamino-p-(carbon-2'-ethylhexyl-1'-oxy)-1,3,5-triazine, which are available under the trade name “UVINUL”. T-150 is obtained from BASF; and 2,4,6-tris-(octadecylamino)triazine, also known as tristearate melamine (“TSM”).

[0057] Additives based on hindered phenols have hydroxyl groups as terminal functional groups. There are no particular limitations on additives based on hindered phenols, and specific examples include: pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010, manufactured by BASF), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (Irganox 1076, manufactured by BASF), tris-(3,5-di-tert-butyl-4-hydroxybenzyl)-isocyanurate (Irganox 3114, manufactured by BASF), 3,9-bis-{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)-propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro-[5,5]undecane (Sumilizer-GA-80, manufactured by Sumitomo Chemical Co., Ltd.), etc.

[0058] Additional thermally stable organic triazine compounds or oligomers are disclosed in U.S. Patents Nos. 6,268,495, 5,976,208, 5,968,635, 5,919,847 and 5,908,598 to Rousseau et al., which contain at least one nitrogen atom in addition to those nitrogen atoms located on the triazine ring.

[0059] Other examples of charge-enhancing additives are provided in U.S. Publication No. 2011 / 0137082 (Li et al.), U.S. Patent No. 8,613,795 (Li et al.), No. 7,390,351 (Leir et al.), U.S. Patent No. 5,057,710 (Nishiura et al.), and U.S. Patent Nos. 4,652,282 and 4,789,504, both of which are granted to Susumu et al., and U.S. Patent No. 8,790,449 B2 (Li et al.).

[0060] Any suitable amount of charge-enhancing additive can be added. The charge-enhancing additives disclosed herein can be effective even in relatively small amounts. Typically, the charge-enhancing additive is present in the blend in an amount ranging from up to about 10% by weight, more typically from 0.02% by weight to 5% by weight, based on the total weight of the thermoplastic resin and the charge-enhancing additive blend. In some embodiments, the charge-enhancing additive is present in an amount ranging from 0.1% by weight to 3% by weight, 0.1% by weight to 2% by weight, 0.2% by weight to 1.0% by weight, or 0.25% by weight to 0.5% by weight.

[0061] Membranes with adsorbents and nonwoven porous meshes

[0062] Alternatively or additionally, porous membranes may be used to replace and / or combine with nonwoven fiber webs. The membrane may be a polyolefin porous membrane, a polyacrylonitrile porous membrane, a polycarbonate porous membrane, a polyester porous membrane, a cellulose ester porous membrane, a polyamide porous membrane, a polyethersulfone porous membrane, a polysulfone porous membrane, a polyacrylonitrile nanofiber membrane, a PVDF nanofiber membrane, a cellulose ester nanofiber membrane, a polyvinyl acetate or polyvinyl alcohol nanofiber membrane, a nylon membrane, or a polyvinyl butyral nanofiber membrane.

[0063] The membrane can be manufactured by, for example, TIPS (thermal phase separation), SIPS (solvent phase separation), VIPS (vapor phase separation), stretching, track etching, or electrospinning (e.g., PAN fiber membrane).

[0064] For example, the above can be used relative to Figures 1 to 2The described technique is used to wrinkle the membrane. In some embodiments, elastic fibers or filaments are positioned between the membrane layer and one or more nonwoven porous webs. However, it is explicitly envisioned that in some embodiments, multiple elastic filaments are positioned between a first membrane layer and a second membrane layer, which may have the same or different compositions. The membrane layer may comprise a membrane and one or more stacked, laminated, or bonded nonwoven webs.

[0065] Alternatively or additionally, the nonwoven porous mesh may include an adsorbent material. Adsorbent particles may be disposed on the surface of the nonwoven mesh or throughout its entire depth. An example of an adsorbent material is untreated or chemically treated activated carbon. Other examples of porous adsorbent structures include silica gel and activated alumina. Other adsorbents include crystalline aluminosilicate or zeolite or molecular sieve adsorbents and metal-organic frameworks (MOFs). Other adsorbent materials may also be functionalized polymer adsorbents as described in US 10,780,416B2.

[0066] Manufacturing method

[0067] In one embodiment, the pleated filter media of this application can be manufactured by stretching a first series comprising multiple elastic fibers or filaments. The fibers or filaments are generally not bonded together (e.g., the fibers or filaments of this disclosure are not loosely woven). The multiple elastic fibers or filaments in the first series are held (e.g., using spacers) such that each of the fibers or filaments is substantially parallel to each other and spaced apart by a given distance. Typically, substantially parallel fibers or filaments should not contact the nearest adjacent fiber or filament in the working portion of the finished product. In one embodiment, the elastic fibers or filaments are held at a spacing of at least 2, 4, 5, or even 6 fibers or filaments per inch. In one embodiment, the elastic fiber filaments are held at a spacing of up to 8, 10, 12, 15, 20, or even 25 filaments per inch. Typically, the spacing of the fibers or filaments is chosen to achieve the desired pleating of the nonwoven web without causing significant pressure variations.

[0068] Figure 3The diagram shows an exemplary configuration of the first series of fibers 32, wherein the fibers are knotted at either end and combs 35 and 37 are used at both ends to keep the fibers substantially parallel. The first series of filaments is placed between a first nonwoven porous fiber web 34 and a second nonwoven porous fiber web 36. Either or both of the nonwoven porous webs 34 and 6 may contain adsorbent particles. The nonwoven web 36 is placed below a plurality of stretched parallel fibers, with the adhesive side contacting the fibers. A second adhesive-coated web 34 is placed above the plurality of stretched parallel fibers, with the adhesive side contacting the fibers. Additional and optional nonwoven or woven porous webs may be sprayed with adhesive and placed on the aforementioned laminate. A paperboard roller then gently compresses the laminate to remove any air pockets, causing the nonwoven and / or woven webs to bond together with the filaments positioned between the two webs.

[0069] The manual holding of the stretched parallel fibers is then released, allowing the filaments to relax, thereby causing the laminated medium (web-adhesive-fiber-adhesive-web-optional-adhesive-web) to wrinkle. Additional details on how the wrinkled medium can be made can be found in U.S. Provisional Patent Application 63 / 434365, filed December 21, specifically in paragraphs [0027-0037], which are incorporated herein by reference.

[0070] The fiber or filament may preferably be stretched to a desired length before reaching its elastic limit or yield point. As used herein, % stretch is defined as the difference between the length of the stretched fiber or filament and the length of the initially relaxed fiber or filament, divided by the length of the initially relaxed fiber or filament, and converted to a percentage. In one embodiment, the elastic fiber is stretched to 50% to 250%. The filament or fiber may be stretched beyond 250%, provided that the filament does not exceed its elastic limit of deformation or breakage during the manufacture of the pleated medium disclosed herein.

[0071] The first and second nonwoven webs are positioned on either side of the drawn filament. The first and second nonwoven webs can be the same or different. These nonwoven webs are selected based on the desired performance characteristics. The selected nonwoven webs can differ in composition, basis weight, thickness, porosity, etc.

[0072] A first nonwoven web and a second nonwoven web are directly bonded together such that the first nonwoven web contacts the second nonwoven web, optionally using an adhesive as shown in the examples below. In one embodiment, an adhesive is used to directly bond (or adhere) the first and second nonwoven webs together. Such adhesives may include pressure-sensitive adhesives or hot-melt adhesives. Pressure-sensitive adhesives are known in the art and are typically adhesives that adhere based on room temperature conditions when pressure (e.g., finger pressure) is applied. Exemplary pressure-sensitive adhesives include natural latex or synthetic polymers such as (meth)acrylates. Commercially available pressure-sensitive adhesives include spray adhesives available from 3M Company, Maplewood, MN, USA, under the trade name “3M Super 77 Multipurpose Adhesive”. Hot-melt adhesives are adhesives that are thermoplastic polymers that, when heated above their softening point and applied to a surface in their softened state, penetrate the surface and cure to ensure cohesion. Exemplary hot-melt adhesives include: Bostik HM-9041, available from Bostik Inc., Wauwatosa, WI, USA; and Tailored HM011BA, available from Tailored Chemical Products Inc., Hickory, NC, USA. In embodiments of this application, when the adhesive is applied, the weight of the adhesive used per unit area is less than the unit area weight of the nonwoven web. In one embodiment, the unit area weight of the adhesive is less than 0.5%, 0.4%, 0.3%, 0.2%, or even 0.1% of the unit area weight of the nonwoven porous fiber web in the article. Ideally, the adhesive should not affect the performance of the article and should be foldable, meaning that the adhesive can maintain adhesion (or maintain the bond between two layers of nonwoven web) during manufacturing when the stretched fibers or filaments are relaxed. In one embodiment, the adhesive in the pleated article is at least 1 gsm, 2 gsm, 4 gsm, 5 gsm, or even 6 gsm (grams per square meter). In another embodiment, the adhesive in the pleated article is at most 8 gsm, 10 gsm, 15 gsm, 20 gsm, 40 gsm, 60 gsm, 80 gsm, or even 100 gsm. In yet another embodiment, the first nonwoven web and the second nonwoven web are directly welded together, such that the first nonwoven porous fiber web and the second nonwoven porous fiber web are in close contact. Such welding techniques are known in the art and include thermal bonding or ultrasonic welding.

[0073] After bonding (or adhering) the first and second nonwoven porous fiber webs together, tension is released on the stretched elastic fibers or filaments, and the resulting product becomes wrinkled or gathered, as... Figure 1 As illustrated schematically. Typically, after the tension on the stretched elastic fiber or filament is released, it may take hours or days for a gathered fabric to reach its final gathered state as the structure reaches equilibrium. In one embodiment, heat can be used to achieve this stabilization state more quickly.

[0074] In addition to the first and second nonwoven webs, additional layers (e.g., a third layer) can be added to the pleated article to provide additional functionality. The third nonwoven or woven layer can be added before the tension on the filament or fiber is released, such that the third layer is also pleated or gathered. In another embodiment, the third layer is added after the tension on the filament or fiber is released, such that the third layer is a flat layer bonded to the pleated or gathered article. Exemplary third layers include cover netting, which serves to protect the underlying article from abrasion, contamination, etc. The third layer can also provide aesthetic and visual functionality.

[0075] In another embodiment, in addition to the first series of elastic fibers or filaments, a second series of fibers or filaments may be used, wherein the first series of elastic fibers or filaments and the second series of elastic fibers or filaments are positioned non-parallel to each other (e.g., at least 45 degrees or at least 90 degrees). The pleated article is manufactured as described above, except that both series of elastic fibers or filaments are placed between two nonwoven webs. When tension is released on both series of filaments, the resulting article has a more complex pleated pattern, as shown in the embodiment portion of U.S. Provisional Patent Application 63 / 434365, filed December 21, 2023.

[0076] In yet another embodiment, the series of elastic fibers or filaments can be stretched to different percentages, such that when the tension is released, the resulting pleated material includes areas with more pleats and areas with fewer pleats.

[0077] The article disclosed herein is elastically stretchable under tension, meaning that when the pleated article is pulled in the same direction as the length of the elastic fiber or filament, the pleated article can elongate (or flatten) and, when the tension is released, the elongated article returns to its pleated form. In one embodiment, the pleated article is elastically stretchable to at least two or even three times its relaxed length. In some embodiments, the pleated article includes at least one portion that is elastically stretchable under a first tension, wherein a second portion of the pleated filter medium is under a second tension.

[0078] Because the articles of this disclosure have a pleated (or gathered) appearance, the resulting articles have a higher basis weight than the original flat or unpleated nonwoven porous fiber webs. In one embodiment, the gathered articles of this disclosure have a basis weight of at least 20 g / m², 30 g / m², 40 g / m², 50 g / m², 100 g / m², or even 200 g / m². In another embodiment, the gathered articles of this disclosure have a basis weight of up to 200 g / m², 300 g / m², 400 g / m², 500 g / m², 600 g / m², 800 g / m², 1000 g / m², or even 1500 g / m².

[0079] The resulting pleated media is self-supporting, meaning that no additional layers are needed to provide support for the nonwoven web / fiber or filament / nonwoven web construction, optionally including an adhesive. Such articles can be used to filter out unwanted particles from fluids, such as dust, mold, oil mist aerosols, cigarette smoke, pet dander, viruses, bacteria, etc.

[0080] The filter media described herein can have a variety of suitable air permeability. In one embodiment, the air permeability of the filter media is greater than or equal to 2 CFM / sqft, 5 CFM / sqft, 10 CFM / sqft, 15 CFM / sqft, 20 CFM / sqft, 25 CFM / sqft, 30 CFM / sqft, 40 CFM / sqft, 50 CFM / sqft, 75 CFM / sqft, 100 CFM / sqft, 120 CFM / sqft, 150 CFM / sqft, 170 CFM / sqft, 200 CFM / sqft, 275 CFM / sqft, 300 CFM / sqft, 350 CFM / sqft, 400 CFM / sqft, or even 450 CFM / sqft. In some implementations, the air permeability of the filter medium is less than or equal to 450 CFM / sqft, 400 CFM / sqft, 350 CFM / sqft, 325 CFM / sqft, 300 CFM / sqft, 275 CFM / sqft, 250 CFM / sqft, 225 CFM / sqft, 200 CFM / sqft, 170 CFM / sqft, 150 CFM / sqft, 120 CFM / sqft, 100 CFM / sqft, 75 CFM / sqft, 60 CFM / sqft, 50 CFM / sqft, 40 CFM / sqft, 35 CFM / sqft, 30 CFM / sqft, or even 25 CFM / sqft. Combinations of the above ranges are also possible (e.g., greater than or equal to 20 CFM / sqft and less than or equal to 350 CFM / sqft, greater than or equal to 35 CFM / sqft and less than or equal to 170 CFM / sqft, or greater than or equal to 20 CFM / sqft and less than or equal to 350 CFM / sqft). Other ranges are also possible. The air permeability of the filter media can be determined according to ASTM test standard D737 (1996).

[0081] The filtration performance test results of the pleated media articles are discussed in more detail in U.S. Provisional Patent Application 63 / 434365, filed December 21, and are specifically incorporated herein by reference in the embodiments.

[0082] Test methods

[0083] The media examples were evaluated using the following test methods. Unless otherwise specified, at least two samples were tested and the average value was taken for each example (EX) and comparative example (CE).

[0084] Unless otherwise stated, all initial and loaded NaCl permeability and pressure drop tests of the network were conducted at an upwind velocity of 13.9 cm / sec. The network performance listed in Table 3 is based on actual measurements using the listed test methods.

[0085] The respirator sample is mounted on a retainer designed for a specific respirator type, located in the corresponding test chamber for testing. For example, when applicable, a horizontally folded respirator like the Aura respirator is first removed from the headband and pins. The fold is then opened to fit onto an open cylindrical retainer with the respirator outlet or downstream side facing upwards. The sides of the headband, which are pinned or welded, are unfolded and positioned into two recesses on the cylindrical retainer. Optionally, the support has a dome-shaped opening structure in the opening area to provide support for the respirator. With the respirator fully open and mounted on the retainer, a slightly larger cylindrical ring is pushed onto the periphery of the mounted respirator, thus clamping the respirator periphery between the retainer and the ring to form a tight seal. The mounted assembly is then placed in a test chamber that provides further compression during testing to ensure a good seal.

[0086] In another example, a cup-shaped respirator can be mounted in a retainer in a similar manner, but the retainer size is designed for a specific cup style. The retainer with the respirator mounted on it is then positioned and aligned on a testing instrument such as TSI. ™ The test was performed using the Model 8130 High-Speed ​​Automatic Filter Tester (available from TSI Inc., Shoreview, Minnesota). Alternatively, larger cup-shaped respirators or cup-shaped respirator samples with extended circumferences and sufficient mechanical resistance to prevent deformation or collapse under airflow can be placed directly on the TSI. ™ The Model 8130 high-speed automatic filter tester (available from TSI Corporation, Shoreview, Minnesota) features a lower chuck on top, with its outlet or downstream side facing upwards. As the upper chuck descends upon a test command, the respirator periphery is compressed and sealed under pressure between the upper and lower chucks.

[0087] Other types of respirators, such as 3M VFlex ® The respirator, or a vertically folding respirator purchased from 3M Company, Maplewood, MN, USA under the trade name “3M Disposable Respirator 9105 or 9010”, can be mounted on a retainer specifically designed for its shape and size and tested in a similar manner.

[0088] Respirator retainers and test chambers can be made of a variety of materials. Some are chosen because of their transparency, which facilitates observation of the test. Examples include plexiglass, polycarbonate, acrylic, and polystyrene.

[0089] NaCl initial test and quality factor : The pressure drop and osmotic percentage of the respirator can be measured using a punch containing NaCl particles, delivered at a flow rate of 85 liters / minute or LPM, and using TSI. ™ The Model 8130 high-speed automatic filter tester (available from TSI Corporation, Shorevell, Minnesota) is used for determination. The pressure drop (dP, mm H2O) of the filter medium passing through the filter sample can be measured using an MKS pressure transducer (available from MKS Instruments, Andover, Massachusetts).

[0090] For transient NaCl tests conducted at 85 liters per minute (LPM) using particles with a diameter of 0.075 µm, the particles are generated from a 2% NaCl solution to provide an aerosol containing particles at a gaseous concentration of approximately 16 mg / m³–23 mg / m³. This automated filter tester can operate with both the heater and particle neutralizer functioning. The initial NaCl permeation and pressure drop tests last approximately 19 seconds.

[0091] NaCl particles were forced to pass through an opening with a diameter of 11.4 cm or an opening of 102 cm at a rate of 85 LPM. 2 The medium sample.

[0092] The percentage of NaCl penetration is defined by the following formula: %Pen = (downstream concentration / upstream concentration) × 100 The percentage permeability and pressure drop of NaCl are used to calculate the quality factor "QF" using the following formula:

[0093] A higher initial QF value indicates better initial filtration performance. A lower QF value is effectively associated with lower filtration performance.

[0094] NaCl load test : According to the procedures described in the tester manual, in TSI ™Loading tests were performed on a Model 8130 high-speed automatic filter tester (available from TSI Inc., Shoreview, Minnesota, USA). Samples were subjected to continuous NaCl testing at 85 LPM with the particulate ion generator running. The flat sample being tested had a diameter of 100.2 cm. 2 The exposed area, the nominal windward velocity of flat and pleated media sheets is 13.9 cm / sec.

[0095] The sample can be loaded with NaCl particles until a predetermined amount of NaCl particles is reached or until the pressure drop reaches a predetermined threshold. Particle concentration and the percentage particle permeability through the filter can be measured at the filter inlet and outlet using a calibrated photometer.

[0096] like Figures 1 to 3 As described herein, pleated media can be used as filter media for respiratory protection. For example, pleated media can be used in disposable respirators to form one or more layers of the respirator body, or in reusable respirators to form layers or portions of pleats. These and other examples are discussed in more detail in U.S. Provisional Patent Application Serial Nos. 63 / 496002 and 63 / 496003, both filed April 13, 2023.

[0097] Pleated media can also be used to improve the fit of respirators. Because pleated media is stretchable and elastic, it can conform to different face shapes and sizes. Fit features (e.g., features added to the respirator body to improve fit) can also have lower contact pressure while having the same or higher levels of filtration performance as the respirator media.

[0098] Fit features made of pleated media can act as spacers to help the respirator fit better to multiple facial features—such as narrower or shorter faces. Stretching can also help maintain the respirator's fit as the user changes facial expressions or moves their head.

[0099] The conformal features formed by the pleated filter media also increase the filtration area of ​​the respirator. The increased filtration area reduces the ambient temperature inside the respirator (which is typically warmer than the ambient air due to the wearer's exhaled breath).

[0100] The fit features described herein are illustrated with respect to several exemplary breathing patterns in the accompanying drawings. However, it is explicitly contemplated that the fit features described herein can be modified to suit any number of respirator patterns, such as those described or illustrated in U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023, the entire contents of which are incorporated herein by reference.

[0101] Figures 4 through 7 illustrate the nose pad according to the embodiments described herein. As described in Figures 4 through 7, the nose pad offers many advantages over conventional foam nose pads. How the respirator conforms to the wearer's nose is a significant contributor to wearer comfort. Sealing formation requires the nose pad to conform to the user's nasal bridge while maintaining a rigid position upon placement. This is inconsistent with the requirements for comfort in order to improve compliance.

[0102] Many respirators include a formable nose clip (usually metal) and a nose pad. Traditionally, the nose pad is made of open-cell or closed-cell foam, which is cut and placed below or near the rigid nose clip. After the user shapes the metal nose clip for the bridge of the nose, the metal nose clip will experience some "rebound." A compliant nose pad helps maintain a seal. Additionally, the nose pad helps distribute the contact pressure exerted by the nose clip on the user's face, which helps improve comfort. However, improvements are still needed. Previous designs have attempted to allow for more cushioning by using multiple layers of material (e.g., folds). However, while multiple layers provide more cushioning when compressed, they do not expand as the respirator moves across the user's face (e.g., talking, smiling, shaking the head).

[0103] This document describes a nose pad that can be used with or without conventional nose pads. The nose pad described herein is formed of a pleated medium and therefore allows for active stretching and contraction as the wearer's face moves, thereby maintaining a good seal. The nose pad described herein is formed of a pleated filter medium, such that the nose pad has the same or higher filtration performance, ensuring that the permeation of aerosols through it will not reduce the filtration efficiency level of the filter. In some embodiments, the nose pad of this document may be formed from recyclable materials.

[0104] Traditional nasal pads are typically made of polyurethane. The respirator market strongly favors a shift towards more sustainable and recyclable materials. Foams, such as polyurethane foam, are formed through cross-linking and therefore cannot be remelted, which is essential for recyclability.

[0105] Traditional nose pads are typically manufactured by supplying them in roll form. In contrast, the nose pad described in this paper can be formed using a standard respirator manufacturing process. The self-supporting properties of the pleated medium mesh provide compliance to form a fit around the bridge of the nose, while the manufacturing process produces a seamless, continuous length.

[0106] Figures 4A to 4DA cup-shaped respirator 400 with a nose pad 406 is illustrated. The respirator 400 includes a nose clip (not shown) and a conventional nose pad 404. In the illustrated embodiment, the nose pad 406 is sealed to the respirator 400 along one edge (e.g., along a sealing edge 408). In some embodiments, the nose pad 406 may be welded, bonded, spot-bonded, sewn, or sealed to the respirator body 400 by another suitable method. In some embodiments, the nose pad 406 is adhered to the respirator body, for example, using a heat-melt, pressure-sensitive, or other suitable adhesive. Sealing the nose pad 406 to the respirator body 400 allows filtration of ambient air entering the gap formed between the nose pad 404 and the nose pad 406. In some embodiments herein, the nose pad 406 provides the same or greater filtration efficiency as the respirator body 400.

[0107] The nose pad 406 is formed from a pleated medium according to an embodiment of the herein, making it stretchable and fully elastic, such as from Figures 4B to 4D The transition is illustrated. When the applied force is removed, the nose pad 406 returns to or substantially returns to its original state. Figure 4B The relaxed position. As used in this article, essentially recovery means that the nose pad 406 recovers at least 80%, or at least 85%, or at least 90%, or at least 95%, or at least 99%.

[0108] Figure 4B An initial length 410 of the nose pad in a static stretched state is illustrated. It is explicitly envisioned that, in some embodiments herein, length 410 may represent some stretching of the nose pad from its true static state (e.g., the state of the pleated medium forming the nose pad without applied compression or tension). When a wearer puts on the respirator 400, the wearer's nose engages with the nose pad 406, and as illustrated by lengths 420 and 430, the nose pad 406 stretches. In some embodiments, the nose pad may stretch from a length of 8 cm in the static state to a length of 10 cm in the stretched state. In some embodiments, the nose pad may stretch at least 5% along its longest diameter. In some embodiments, the nose pad may stretch at least 10% along its longest diameter. In some embodiments, the nose pad may stretch up to 25%, or more than 50%, or even at least 100% along its longest diameter. In some embodiments, the stretchability is limited by the length of the inner perimeter—for example, the nose pad material may be able to stretch up to 50% of its relaxed length, but may only stretch 25% before mating with the inner perimeter of the respirator body 400. When the user removes the respirator 400, the length returns to or essentially returns to the length 410.

[0109] Although the respirator 400 is in Figures 4A to 4DThe embodiment is illustrated as having both nose pad 406 and nose pad 404, but it is explicitly envisioned that the embodiment described herein may utilize nose pad 406 without nose pad, so that the nose pad is primarily responsible for distributing contact pressure along the bridge of the nose area.

[0110] The nose pad 406 is illustrated as having an edge 408 that seals to the respirator body 402; however, it is explicitly contemplated that in some embodiments, the nose pad 406 seals only along an additional edge—for example, the nose pad 406 may seal along at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or along the entire periphery of the nose pad. The nose pad 406 may also take any suitable shape. For example, the nose pad 406 may be rectangular, square, triangular, circular, etc. The nose pad 406 may also have an irregular shape cut therein to better conform to the bridge of the nose. For example, in Figure 6A and Figure 6C Some example shapes are shown in the figure.

[0111] Figures 5A to 5D An example of a horizontally folding respirator according to an embodiment of this document is shown. Figure 5A An example is shown of a nose pad 504 welded along weld 502 to the respirator body 500. The nose pad 504 is formed from a folded sheet of corrugated medium to increase cushioning. However, it is explicitly envisioned that some embodiments utilize a single sheet of corrugated medium to form the nose pad. As described herein, the corrugated medium can be made from nonwoven mesh of varying thicknesses, thus allowing for customization of the amount of compliance of the nose pad 504.

[0112] like Figure 5B As illustrated, the nose pad 520 has a bridge length 522 and a width 524. The nose pad 520 is sealed to the respirator 500. In some embodiments, the nose pad is sealed along the edge of the respirator body. In some embodiments, the nose pad is sealed along a sealing line within the respirator body along its edge.

[0113] Figures 5A to 5D The illustration shows a nose pad sealed to the top panel of the respirator 500. The presence of the nose pad 502 on the top panel helps reduce the flow and accumulation of humid exhaled air, which can cause glasses to fog up.

[0114] from Figures 5C to 5D The transformation illustrates how the nose pad stretches from a relaxed state 530 to a stretched state 540 under tension.

[0115] The nose pad 504 is illustrated as having a sealing edge 502; however, it is explicitly envisioned that in some embodiments, the nose pad 504 may seal only along an additional edge—for example, the nose pad 504 may seal along at least 50% of the periphery of the nose pad 504, or at least 60% of the periphery of the nose pad 504, or at least 70% of the periphery of the nose pad 504, or at least 80% of the periphery of the nose pad 504, or at least 90% of the periphery of the nose pad 504, or at least 95% of the periphery of the nose pad 504, or along the entire periphery of the nose pad.

[0116] Figures 6A to 6D An example of a respirator body with a nasal pad according to an embodiment of this document is shown. Figure 6A An example of a cup-shaped respirator 610 according to an embodiment of this document is illustrated, which has a nose pad 612 welded along the top sealing line of a respirator 620. The nose pad 612 has a notch in the middle, which can be tailored to various shapes and sizes to facilitate conformity in the nasal region—a rounded triangle is illustrated. Figures 6A to 6D In the exemplary embodiment, the nose pad 612 is formed of two pleated media layers (such as... Figure 6C (As illustrated). The pleats of the nose pad 612 are oriented generally vertically, causing the nose pad to stretch horizontally. In some embodiments, the pleated medium selected for the nose pad 612 can provide the same or higher filtration efficiency of ambient air as the respirator body.

[0117] Figure 6A A nasal foam 614 is illustrated behind the nasal pad 612. However, it is explicitly envisioned that embodiments described herein include other configurations. For example, the respirator 610 may be formed having a nasal pad 612 formed of only one or more media layers. The nasal pad 612 may be formed of a pleated media configured to be horizontal, vertical, or stretched in both directions. In some embodiments, the nasal pad 612 may be formed of a substantially unstretched media. The nasal pad 612 in Figure 6B The shape is exemplified as concave; however, it is explicitly envisioned that other shapes are possible, such as convex, irregular, or other suitable shapes. Furthermore, although... Figures 6A to 6C The nose pad 614 is illustrated herein, but it is clearly envisioned that in some embodiments herein, the nose pad is not present.

[0118] Figure 6B An example is shown of a cup-shaped respirator with a nose pad 620 welded along its inner surface. (Compared to...) Figure 6A and Figure 6C In contrast, the nose pad 620 is solid and has no convex or incision features.

[0119] Figure 6CAn example is illustrated of a cup-shaped respirator having a nose pad 630, which has an additional cover pad 632 welded along its inner surface. The cover pad 632 may or may not have the same shape and dimensions as the nose pad 630. Both the nose pad 630 and the cover pad 632 are formed of two corrugated media layers. The two stretchable, flexible corrugated material layers provide additional cushioning and sealing. Although two corrugated media layers are illustrated, it is clearly envisioned that additional layers may be possible in some embodiments.

[0120] Figure 6D An example is a cup-shaped respirator 640 having a nose pad 642 welded along the inner surface of the body of the respirator 640. Figure 6D The illustrated nose pad 642 is made of a pleated medium and replaces a portion of the cup-shaped respirator body 640 surrounding the nasal region, thereby allowing the nasal region to be more flexible and stretchable than the rest of the respirator body. While a circular nose pad shape 642 is illustrated, it is explicitly envisioned that other shapes and sizes are possible in other embodiments. The medium selected for the nose pad 642 may have the same or better filtration efficiency as the medium used for the respirator body 640. In some embodiments, the nose pad 642 may be combined with a nose clip to conform to a range of nasal bridge sizes.

[0121] Another area of ​​respirator discomfort involves filtering face mask respirators (FFRs) that include a face seal. The presence of a face seal results in a high fit factor, which is required in many industries. Face seals are typically made of impermeable materials (e.g., rubber or PVC), which are uncomfortable. Some FFRs have moisture-permeable face seals, such as those described in PCT Publication WO 2014 / 110075, published on 7 July 2014. However, the manufacturing cost of such permeable face seals is generally prohibitive.

[0122] Figures 7A to 7H A cup-shaped respirator with a face seal is illustrated according to some embodiments of this document. Figure 7A An external view 702 of a cup-shaped respirator 700 is shown. Figure 7B An internal view 704 of a cup-shaped respirator 700 is illustrated. The illustrated respirator 700 is the 8210Plus respirator, available from 3M Corporation in St. Paul, Minnesota, USA. However, while the 8210Plus respirator is illustrated, it is explicitly envisioned that the embodiments described herein can be applied to other cup-shaped respirator designs. Furthermore, it is explicitly envisioned that other respirator designs, such as horizontal three-fold, vertical fold, and duckbill types, can also benefit from the face seal described herein.

[0123] Figures 7C to 7D An example is a respirator 710 with an added face sealing layer 712. Figure 7CAn example is a pleated medium layer 712 that is sealed to the periphery of the respirator opening under tension (as illustrated by reference numeral 716 in the figure). Figure 7D A layer 712 is illustrated, in which an opening is cut out to form a face seal 718 having an inner periphery 714. The face seal has a region extending substantially from the periphery of the respirator body to the inner periphery 714. The face seal layer 712 is stretched in the direction indicated by arrow 718. However, while horizontal stretching in direction 718 is illustrated, it is clearly envisioned that in some embodiments, the corrugated medium may be welded to the respirator body such that it is configured to stretch in a vertical direction.

[0124] The resulting respirator 714 has a smaller opening (peripheral 714) than the original 8210Plus respirator. The face seal 712 illustrates only one example shape, but it is clearly envisioned that other shapes with larger or smaller areas, or different peripheral shapes, can be formed. For example, while the peripheral 714 is typically circular, it can also be oval or irregular in shape—for example, with a notch removed for the wearer's nose or chin. Additionally, in some embodiments, smaller or larger openings may be present.

[0125] Figure 7E An embodiment of a respirator 720 according to this document is illustrated, the respirator having a pleated medium welded to the periphery of its opening to form a face seal 724. The face seal 724 has a notch 722 around a nasal region for better conforming to the wearer's nose. The pleats of the pleated medium forming the face seal 724 are vertically oriented such that the face seal 724 is stretched in the direction indicated by arrow 726.

[0126] Figure 7F An example of a respirator 730 according to an embodiment herein is illustrated, the respirator having a pleated medium welded to form a face seal 734. The face seal 734 also has a notch 732 removed from an originally substantially annular face seal. The pleats of the pleated medium forming the face seal 734 are horizontally oriented such that the face seal 734 is stretched in the direction indicated by arrow 736. However, Figures 7E to 7F Examples are shown that are essentially stretched only vertically or horizontally. It is explicitly envisioned that a respirator according to an embodiment of this document may have a face seal layer that stretches in both the vertical and horizontal directions, or have multiple face seal layers that overlap with different fold orientations, such that the multi-layer face seal can stretch in different orientations.

[0127] Figures 7G to 7IDifferent views of a respirator 740 formed of pleated media according to an embodiment of this document are illustrated. A cup shape is formed using an 8210Plus shell, available from 3M Inc. in St. Paul, Minnesota. However, it is explicitly contemplated that other shell shapes may be used according to the embodiments of this document. To form the respirator 740, a filter layer 742 of pleated media is stretched on the outer or concave side of the shell 746 while a face seal layer 744 is placed under tension on the inner side of the cup shape. The three layers (filter layer, shell, and face seal) are then welded around the perimeter. In the embodiments of this document, the pleated media used as the filter layer covering the shell may have the same or different composition as the pleated media used for the face seal layer.

[0128] In addition, although relative to Figures 7G to 7I Only a single filter layer and a single face seal layer are described, but it is explicitly envisioned that multiple layers of pleated media could be used to form the face seal 744 and / or the filter layer 742. In this embodiment, the pleats in the face seal layer 744 are oriented in a substantially vertical direction, such that the face seal can be stretched in a generally horizontal direction. However, it is explicitly envisioned that a respirator according to the embodiments herein may have one or more face seal layers made of pleated media configured to stretch in any of the vertical, horizontal, mixed horizontal and vertical directions, or in an angled direction. Figure 7H An internal view of a respirator 740 is shown, in which a portion of the face seal 744 has been removed, leaving a substantially annular face seal 752. Figure 7I A side view of a respirator 740 is shown, illustrating the pleated medium in both the respirator body and the face seal.

[0129] Figures 7C to 7I An example is illustrated where one or more pleated media layers are used to form a face seal on a respirator. It is explicitly envisioned that a respirator according to an embodiment herein may have a face seal layer having the same or different composition as the respirator body. For example, as... Figures 7C to 7F As illustrated, the respirator body is formed of a non-wrinkled medium, while the face seal is formed of a wrinkled medium. However, it is also explicitly envisioned that the respirator body could be formed of a first wrinkled medium, and the face seal layer of a second wrinkled medium, such as... Figures 7G to 7I The illustrated respirator 740. For example, it may be desirable to have a different composition, such as a face seal with greater thickness to improve comfort, or a filtration capacity with higher filtration efficiency.

[0130] In some embodiments described herein, the formation of the facial seal from the facial sealing layer can be completed during manufacturing in the same steps as forming the cup-shaped respirator (or other breathing design). For example, ultrasonic welding can be used to attach the respirator filter layer to the cup-shaped structure. In embodiments where both the respirator filter layer and the facial sealing layer are corrugated media, the facial seal can be added during the same steps. However, other attachment mechanisms, such as bonding, spot bonding, adhesives, stitching, etc., can also be used.

[0131] Although Figures 7A to 7H The formation of a facial seal within a facial sealing layer is described by cutting orifices in the layer, but it is explicitly envisioned that other methods may be used. Examples include die-cutting, laser cutting, high-energy light cutting, and ultrasonic cutting. The facial sealing layer can be sealed using a mold with orifices and can be sliced ​​prior to respirator formation to create the facial seal (e.g., sealing a filter layer and a facial sealing layer together).

[0132] Figures 7J to 7K An embodiment of this invention with a harness-fit feature is illustrated. Many breathing designs require straps or harnesses to hold the respirator body against the wearer's face. Some strap and harness designs may cause irritation over time due to the need for taut straps or uncomfortable placement to maintain a proper seal between the respirator body and the wearer's face. However, pleated media can provide sufficient holding force while reducing irritation.

[0133] Figure 7J and Figure 7K The illustration shows a respirator 760 comprising a strip 762 formed of a corrugated medium. In some embodiments, the strip 762 is formed from a first portion of the corrugated medium, while the body of the respirator 760 is formed from a second portion having a corrugated medium composition that is the same as or different from the first portion. However, in some embodiments, a single corrugated medium portion forms both the strip portion 762 and the respirator body 760, thus forming a single article of articles.

[0134] In some implementations, the strip 762 has a strip diameter 766 that is similar in size to the height 767 of the respirator body. However, the strip 762 can have any suitable strip diameter 766. A wider strip diameter 766 can distribute the holding force over a wider area of ​​the user's head, thereby reducing the irritation experienced by the wearer.

[0135] In some implementations, an opening or slit 764 is provided in the restraint 762, which is configured to fit the user's ear, as the wearer may find it more comfortable to leave their ear uncovered by the restraint 762.

[0136] According to the embodiments described herein, the restraint 762 is formed of a pleated medium having pleats oriented such that it is configured to stretch as indicated by arrow 768, so that the circumference of the respirator 760 can be expanded to accommodate wearers with different head circumferences.

[0137] Although Figure 1 Figures 7 illustrate embodiments of the fit feature in horizontally folded and cup-shaped models of the respirator, but it is clearly envisioned that other respirator models may benefit from the fit feature described herein. Nasal pads and facial seals formed from pleated media can be used in a variety of disposable respirator models to provide improved breathability while maintaining high filtration capacity. Some examples of respirator models that may benefit from pleated media include: tri-fold respirators (such as U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023). Figure 4A As illustrated in Figure 4E, this U.S. provisional patent application is incorporated herein by reference, as well as cup-shaped respirators (such as U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023). Figure 5A As illustrated in Figure 5E, this U.S. provisional patent application is incorporated herein by reference, and vertically folding respirators (such as U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023). Figure 6A As illustrated, the U.S. provisional patent application is incorporated herein by reference), folding respirators, pleated respirators (such as U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023). Figure 6B The illustrated U.S. provisional patent application is incorporated herein by reference, and the "duckbill" respirator (such as U.S. Provisional Patent Application Serial No. 63 / 496002, filed April 13, 2023). Figure 6C As illustrated, the U.S. provisional patent application is incorporated herein by reference.

[0138] Figure 8 A method for manufacturing a respiratory protective device according to an embodiment of this document is illustrated. Method 800 can be used to form a respirator of any disposable respirator type that can benefit from the nose pad or face seal as described herein.

[0139] At frame 810, a respirator medium is obtained. A pleated medium 812 may be obtained for use in one or more layers or panels of a respirator and may be used as a respirator filter layer. In some embodiments, the respirator medium may include a face sealing layer. In some embodiments, the respirator medium may also include a nasal pad layer.

[0140] A flat medium 814 can be obtained for one or more layers or panels. Other media 816 can also be used. For example, a medium with anti-fogging properties can be obtained for a part of a respirator. Alternatively, a shell layer can be obtained for use as, for example, the shell of a cup-shaped respirator.

[0141] At frame 820, one or more of these layers undergo one or more processes. For example, the cup shell may be formed 822. One or more layers may be electret 824 to exhibit electret properties that attract and bind microparticles and droplets. Other processes 828 may be performed.

[0142] The preforming step 826 required for the cup-shaped respirator may be a rate-limiting step in respirator manufacturing because the shell curvature must be conformed to the flat medium in multiple directions, which may include cutting and welding the medium in a sinusoidal shape. Note that some embodiments in this paper that use dashed slit layers (sometimes called skip slit layers) to form the cup-shaped structure do not require a preforming step.

[0143] The dashed slit layer consists of a surface that has been cut (e.g., trimmed) with a dashed pattern. US PAP 2019 / 0187345 describes and exemplifies several patterns that may be used in embodiments herein. The slit pattern may be a diamond-shaped slit pattern, such as that in US 2019 / 0187345. Figure 1 The slit patterns illustrated in Figures 4 and 12 are incorporated herein by reference. Slit patterns can also be non-diamond slit patterns, which also allow expansion in at least one direction, as shown in Figure 5 of US2019 / 0187345, for example. Figure 8 Figures 10, 11, and 14 are illustrated herein and are incorporated herein by reference. Slit patterns may also have two openings of different sizes or shapes, as illustrated in Figures 6 and 15 of US 2019 / 0187345, which are incorporated herein by reference. Slit patterns may also have three openings of different sizes or shapes, as illustrated in Figures 7, 9, and 13 of US 2019 / 0187345, which are incorporated herein by reference. Slit patterns may also have two openings of different sizes or shapes that allow expansion in two directions, as illustrated in Figures 16 and 18 of US 2019 / 0187345. Slit patterns may also have three openings of different sizes or shapes that converge to provide expansion in at least three directions, as illustrated in Figure 19 of US 2019 / 0187345.

[0144] However, other shell solutions can also be used. In some implementations, an elastic mesh can be used as the shell. The elastic mesh can be formed by molding, extrusion, or another suitable method.

[0145] At frame 830, a laminate is formed. The laminate may consist of one or more filter layers 832. Filter layers 832 may be corrugated media and / or flat media layers. The laminate 832 may include a face sealing layer. The face sealing layer may have a pre-formed inner diameter from a previous cutting step (not shown). The laminate 832 may also include a nose pad layer. The laminate may include a cover mesh 834. The laminate may include a housing 836, such as a jump-slit housing, a corrugated housing, or another suitable housing component. The laminate may include a layer 838 that incorporates an adsorbent capable of adsorbing or absorbing gases, vapors, etc. An example of an adsorbent commonly used in filtration is activated carbon. The layer containing activated carbon may be a corrugated media layer or a flat media layer. The activated carbon layer may be a single layer, such as having carbon attached to the surface of a fiber mesh or another suitable adsorbent. Other layers 839 may be present, such as fluid-resistant layers or reinforcing layers. Although activated carbon is described herein as an adsorbent material, other adsorbent materials are clearly anticipated to be suitable. For example, polymeric adsorbents can be used in the embodiments described herein.

[0146] At frame 840, a sealing layer stack is formed. The sealing layer stack may include applying a weld 842, a seam 844, an adhesive 846, or other suitable method 848 to join two or more respirator media layers. Additionally, while weld 842 or adhesive 844 is illustrated, it is explicitly envisioned that these may not be complete—for example, dashed or spot welds or adhesives may be used in embodiments herein, which would allow stretching along the seal edge. Similarly, stretching along the seal edge is desirable, and seam 844 may comprise elastic filaments. A seal occurs such that each layer is in close contact with the adjacent layer. Suitable welding techniques are known in the art and include thermal bonding or ultrasonic welding.

[0147] In some embodiments, the sealing layer stack includes sealing a nasal pad to the respirator media layer. Sealing the nasal pad may be performed in the same sealing step as the respirator filter media layer, in a subsequent step, or as a step prior to sealing 840.

[0148] At frame 850, add an accessory. A nose clip 852 can be applied. The nose clip can be used to mold the respirator so that the nasal portion along the runway forms a seal with the wearer's face. The nose clip 852 may include a moldable metal or plastic strip or other suitable mechanism. The nose clip can be applied before or after the layers are sealed, for example, so that it is not visible on the outside or inside of the respirator.

[0149] Nose pads 854 can also be added to increase comfort and improve seal. For example, a custom nose pad is described in PCT Publication WO 2022 / 235472, published on November 10, 2022, however, other foam types and placements are clearly envisioned.

[0150] In addition to, or as a substitute for, a nasal pad may be applied. As described above, a nasal pad may be provided before, during, or after the respirator body formation step.

[0151] An exhalation valve 856 may be added. In some embodiments, the valve-containing portion of the respirator has less stretch than the valveless portion. A restraint 858 may be applied to maintain contact between the respirator and the wearer's face. In some embodiments, the restraint 858 includes strips or ear loops integral with or extending from the pleated media layer of the respirator. In some embodiments, the restraint 858 is a separate component welded, sewn, glued, or otherwise attached to the respirator body. Other accessories 859 may also be added.

[0152] Other pressure-resistant features may be present to help maintain the shape of the respirator before and during use. For example, U.S. Patent No. 6,923,182 B2, published August 2, 2005; U.S. Patent No. 8,640,704, published February 4, 2014; and U.S. Patent No. 6,394,090, published May 28, 2002, all describe features that can be used according to embodiments herein to improve the structural integrity of the respirator body before and during use.

[0153] Figures 9A to 9B An example is given comparing the internal temperatures of respirators with different surface areas. Figure 9A Examples of using Figure 9B The illustrated setup represents internal temperature measurements of three different respirator designs. Respirators 1-3 have different surface areas, with respirator 1 having the smallest internal surface area, respirator 2 having a larger internal surface area than respirator 1, and respirator 3 having the largest internal surface area. With increasing surface area, air velocity increases, allowing the heat from the wearer's exhaled breath to escape the respirator more quickly. Therefore, the embodiments described herein are similarly expected to exhibit a higher degree of comfort relative to temperature—for example, the wearer will feel “cooler” wearing a respirator with additional fit features made of a pleated medium that increases the total surface area for air to pass through.

[0154] In some embodiments described herein, a horizontally folding respirator is provided with one or more fitting features. A horizontally folding respirator is a respirator formed by three panels: a top panel that engages with the wearer's nose, a bottom panel that engages with the wearer's chin, and a central panel extending between the top and bottom panels. The top panel is joined to the central panel along its periphery by a fold, seam, weld, or adhesive, the fold, seam, weld, or adhesive of the first panel extending substantially in common with the edge of the central panel. The bottom panel has an edge defined by its periphery joined to the central panel by a fold, seam, weld, or adhesive, the fold, seam, weld, or adhesive of the second panel extending substantially in common with the edge of the central panel. This type of respirator can be folded flat for storage and, during use, can form a cup-shaped air chamber over the wearer's nose and mouth. This design of the respirator is commonly referred to as a three-fold respirator, a three-panel respirator, a folding respirator, or a horizontally folding respirator, all of which are used interchangeably.

[0155] In some embodiments described herein, the cup-type respirator is provided with one or more fitting features. The cup-type respirator may include a respirator filter layer formed around or to the shell.

[0156] According to the embodiments described herein, other respirator styles with one or more fitting features are also envisioned, such as vertically folding respirators, pleated respirators (such as those in U.S. Patent No. 8,640,704). Figure 1 The respirator illustrated in Figure 4 and column 4, row 25 to column 5, row 29 (this U.S. Patent is incorporated herein by reference), duckbill respirators (such as the respirator described in U.S. Patent 5,322,061 to Bruson).

[0157] Although the respirator described in this article is illustrated as having white filaments in a pleated medium, it is clearly envisioned that naturally colored or dyed filaments could be used, for example, to visually distinguish the model of the respirator.

[0158] Disposable respirators, composed of different layers or panels, are typically sealed around their perimeter to ensure air is forced through the filter material. Seams are usually achieved using welding, bonding, or stitching. However, some embodiments described herein use spot welding or spot bonding to create a sufficient seal while allowing the respirator to stretch. Some embodiments use elastic filaments to form the seams, allowing the filaments to stretch along with the pleated medium.

[0159] Foreseeable modifications and alterations to the invention will be apparent to those skilled in the art without departing from its scope and spirit. The invention should not be limited to the embodiments shown in this application for illustrative purposes. In the event of any conflict or contradiction between the disclosure in this written specification and any document incorporated herein by reference, the written specification shall prevail.

[0160] A disposable respirator includes a wrinkled medium layer. The wrinkled medium comprises a first series of substantially parallel, non-bonded elastic materials between a first nonwoven porous mesh and a second nonwoven porous mesh. The first nonwoven porous mesh is directly bonded to the second nonwoven porous mesh. At least a portion of the wrinkled medium is elastically stretchable under tension. The respirator also includes a fitting feature comprising the wrinkled medium.

[0161] The respirator can be implemented such that the fitting feature includes a nose pad.

[0162] The respirator can be configured such that the nasal pad is sealed to the body of the disposable respirator, the body including the pleated medium layer.

[0163] The respirator can be configured such that at least 10% of the periphery of the nasal pad is sealed to the body.

[0164] The respirator can be implemented such that the periphery includes a straight edge, and the nose pad is sealed to the body along the edge.

[0165] The respirator can be configured such that at least 25% of the periphery is sealed to the body.

[0166] The respirator can be configured such that at least 50% of the periphery is sealed to the body.

[0167] The respirator can be implemented such that the pleated medium layer includes a first pleated medium composition, and the nasal pad includes a second pleated medium composition different from the first pleated medium composition.

[0168] The respirator can be implemented such that the nasal pad includes a first pleated medium having a first thickness, the pleated medium layer includes a second pleated medium, and the first pleated medium is thicker than the second pleated medium.

[0169] The respirator can be implemented such that the nasal pad and the pleated medium layer have the same pleated medium composition.

[0170] The respirator can be configured such that the nasal pad comprises a stretchable material, such that the nasal pad at least partially recovers from a stretched state to a relaxed state, the relaxed state including the nasal pad being sealed to the respirator body, and the stretched state including the nasal pad being subjected to tension while being sealed to the respirator body.

[0171] The respirator can be implemented such that the nasal pad is configured to recover at least 50%.

[0172] The respirator can be implemented such that the nasal pad is configured to recover at least 80%.

[0173] The respirator can be implemented such that the nasal pad is configured to recover at least 90%.

[0174] The respirator can be implemented such that the nasal pad is configured to recover at least 99%.

[0175] The respirator can be configured such that the nasal pad has an extended length in the stretched state, which is 10% longer than the relaxed length in the relaxed state.

[0176] The respirator can be configured such that the stretched length is at least 15% longer than the relaxed length.

[0177] The respirator can be implemented such that the stretched length is at least 30% longer than the relaxed length.

[0178] The respirator can be implemented such that the stretch length is at least 50% of the relaxation length.

[0179] The respirator can be implemented such that the stretch length is at least 100% of the relaxation length.

[0180] The respirator can be implemented such that the fitting feature includes a facial seal.

[0181] The respirator can be implemented such that the face seal includes an outer periphery and an inner periphery, and the outer periphery is sealed to the respirator body.

[0182] The respirator can be implemented such that the outer periphery is sealed to the pleated medium layer.

[0183] The respirator can be implemented such that the outer periphery is sealed to the shell.

[0184] The respirator can be implemented such that the facial seal stretches to confirm the 3D shape of the face.

[0185] The respirator can be implemented such that the disposable respirator has an inner surface, and the face seal is configured to stretch to the extent that it contacts the inner surface of the respirator along the inner periphery of the face seal.

[0186] The respirator can be implemented such that the seal includes welding, bonding, spot bonding or stitching.

[0187] The respirator can be implemented such that the disposable respirator is a horizontally folding respirator.

[0188] The respirator can be implemented such that the disposable respirator is a cup-shaped respirator, and the cup-shaped respirator includes a shell.

[0189] The respirator can be implemented such that the disposable respirator is a vertically folding respirator.

[0190] The respirator can be implemented such that the disposable respirator is a pleated respirator.

[0191] The respirator can be implemented such that the disposable respirator is a duckbill respirator.

[0192] The respirator may include: a nose clip, a nasal foam, a valve, or a harness.

[0193] The respirator may include a strip, and the strip is combined with the pleated media layer to form an integral pleated media article.

[0194] The respirator can be implemented such that the strip includes an opening configured to receive the wearer's ear.

[0195] The respirator can be implemented such that one of the first and second nonwoven layers includes a membrane.

[0196] The respirator can be implemented such that one of the first and second nonwoven layers comprises a fibrous nonwoven material.

[0197] The respirator can be implemented such that the elastic material comprises filaments.

[0198] The respirator can be implemented such that the elastic material includes fibers.

[0199] The respirator can be implemented such that the elastic material comprises a loosely woven fabric.

[0200] A disposable respirator includes: a respirator body including a respirator filter layer; a nose clip attached to the respirator body, the nose clip comprising a formable material; a nose pad attached to the respirator body, the nose pad including a pleated medium, the nose pad being configured to stretch from a relaxed state having a relaxed length to a stretched state having a stretched length when a wearer wears the respirator; and a strip configured to pull the respirator body toward the wearer's face when the disposable respirator is worn.

[0201] The disposable respirator can be implemented such that the pleated medium comprises: a first series of substantially parallel, non-bonded elastic filaments between a first nonwoven porous web and a second nonwoven porous web, and the first nonwoven porous web is directly bonded to the second nonwoven porous web.

[0202] The disposable respirator can be configured such that the pleated medium is a first pleated medium, and the respirator filter layer includes a second pleated medium.

[0203] The disposable respirator can be implemented such that the first pleated medium contains a different composition than the second pleated medium.

[0204] The disposable respirator can be implemented such that the respirator filter layer includes a flat medium.

[0205] The disposable respirator can be implemented such that the flat medium has a flat medium stretch length in the flat medium stretch state that is less than 10% greater than the flat medium relaxation length in the flat medium relaxation state.

[0206] The disposable respirator can be configured such that the nasal pad is at least partially restored from a stretched state to a relaxed state, the relaxed state including the nasal pad being sealed to the respirator body, and the stretched state including applying tension to the nasal pad while the nasal pad is sealed to the respirator body.

[0207] The respirator can be implemented such that the nasal pad is configured to recover at least 50%.

[0208] The respirator can be implemented such that the nasal pad is configured to recover at least 80%.

[0209] The respirator can be implemented such that the nasal pad is configured to recover at least 90%.

[0210] The respirator can be implemented such that the nasal pad is configured to recover at least 99%.

[0211] The respirator can be implemented such that the nasal pad is sealed to the respirator body.

[0212] The respirator can be implemented such that the seal includes welding, bonding, spot bonding or stitching.

[0213] The respirator can be configured to seal at least 30% of the nasal pad around its periphery.

[0214] The respirator can be configured to seal at least 50% of the nasal pad around its periphery.

[0215] The respirator can be configured to seal at least 90% of the nasal pad around its periphery.

[0216] The respirator can be implemented such that the nasal pad is sealed to the inner surface of the respirator body.

[0217] The respirator can be implemented such that the nasal pad is sealed to the outer surface of the respirator body.

[0218] The respirator may include a nasal foam attached to the inner surface of the respirator body.

[0219] The respirator may include a face seal that is attached to the inner surface of the respirator body.

[0220] The respirator can be implemented such that the facial seal comprises a third pleated medium.

[0221] The respirator can be implemented such that the strip and the second pleated medium are combined to form an integrated pleated medium article.

[0222] The respirator can be implemented such that the formable material includes metal.

[0223] The respirator can be implemented such that the disposable respirator is a horizontally folding respirator.

[0224] The respirator can be implemented such that the disposable respirator is a cup-shaped respirator, and the cup-shaped respirator includes a shell.

[0225] The respirator can be implemented such that the disposable respirator is a vertically folding respirator.

[0226] The respirator can be implemented such that the disposable respirator is a pleated respirator.

[0227] The respirator can be implemented such that the disposable respirator is a duckbill respirator.

[0228] A disposable respirator includes: a respirator body including a respirator filter layer; a nose clip attached to the respirator body, the nose clip comprising a formable material; a face seal attached to the interior of the respirator body, the face seal including a corrugated medium; and a strip configured to pull the respirator body toward the wearer's face when the disposable respirator is worn.

[0229] The disposable respirator may include a first series of substantially parallel, non-bonded elastic filaments between a first nonwoven porous web and a second nonwoven porous web, wherein the first nonwoven porous web is directly bonded to the second nonwoven porous web.

[0230] The disposable respirator can be configured such that the pleated medium is a first pleated medium, and the respirator filter layer includes a second pleated medium.

[0231] The disposable respirator can be implemented such that the first pleated medium contains a different composition than the second pleated medium.

[0232] The disposable respirator can be implemented such that the respirator filter layer includes a flat medium.

[0233] The disposable respirator can be implemented such that the flat medium has a flat medium stretch length in the flat medium stretch state that is less than 10% greater than the flat medium relaxation length in the flat medium relaxation state.

[0234] The disposable respirator can be configured such that the face seal includes an outer periphery and an inner periphery, and the outer periphery is sealed to the respirator body.

[0235] The disposable respirator can be implemented such that the outer periphery is sealed to the pleated medium layer.

[0236] The disposable respirator can be implemented such that the outer periphery is sealed to the shell.

[0237] The disposable respirator can be implemented such that the facial seal stretches to confirm the 3D shape of the face.

[0238] The disposable respirator may be implemented such that the respirator includes an inner surface configured to receive the wearer's exhalation, the face seal includes an inner periphery, and the face seal is configured to stretch such that the inner periphery contacts the inner surface of the respirator.

[0239] The disposable respirator can be made to allow for sealing by welding, bonding, spot bonding, or stitching.

[0240] The disposable respirator can be implemented such that it is a horizontally folding respirator.

[0241] The disposable respirator can be implemented such that it is a cup-shaped respirator, and the cup-shaped respirator includes a shell.

[0242] The disposable respirator can be implemented such that it is a vertically folding respirator.

[0243] The disposable respirator can be implemented such that it is a pleated respirator.

[0244] The disposable respirator can be configured to be a duckbill respirator.

[0245] The disposable respirator may include: a nose clip, nasal foam, a valve, or a harness.

[0246] The disposable respirator may include a strip, and the strip is combined with the pleated media layer to form an integral pleated media article.

[0247] The disposable respirator can be implemented such that one of the first nonwoven layer and the second nonwoven layer includes a membrane.

[0248] The disposable respirator can be implemented such that one of the first and second nonwoven layers comprises a fibrous nonwoven material.

[0249] A method of manufacturing a respirator includes obtaining a fitting feature comprising a corrugated medium layer. At least a portion of the corrugated medium is elastically stretchable under tension. The method further includes: forming a respirator body comprising a stack of medium layers; and sealing the stack of medium layers such that the respirator body is coupled to the corrugated medium layer.

[0250] The method can be implemented such that the fitting feature includes a nose pad.

[0251] The method can be implemented such that the stack of sealing media layers includes sealing the pleated media layer to the inner surface of the respirator body.

[0252] The method can be implemented such that the stack of sealing media layers includes sealing the pleated media layer to the outer surface of the respirator body.

[0253] The method can be implemented such that the stack of sealing media layers includes sealing the periphery of the pleated media layer to the respirator body.

[0254] The method can be implemented such that the seal includes sealing at least 30% of the pleated media layer to the respirator body.

[0255] This method can be implemented such that at least 50% of the periphery of the nose pad is sealed to the body.

[0256] The method can be implemented such that the fitting feature includes a facial seal.

[0257] The method can be implemented such that the face seal comprises a stretchable material, such that the face seal is at least partially restored from a stretched state to a relaxed state, the relaxed state including the face seal being attached to the respirator body, and the stretched state including the face seal being subjected to tension while it is attached to the respirator body.

[0258] The method can be implemented such that the facial seal is configured to recover at least 50%.

[0259] The method can be implemented such that the facial seal is configured to restore at least 80%.

[0260] The method can be implemented such that the facial seal is configured to recover at least 90%.

[0261] The method can be implemented such that the facial seal is configured to restore at least 99%.

[0262] The method can be implemented such that the formed respirator includes an inner surface configured to receive the user's exhaled breath, the face seal has an inner periphery, and the face seal is configured to stretch such that the inner periphery contacts the inner surface of the formed respirator.

[0263] The method can be implemented such that the stack of sealing media layers includes sealing the pleated media layer to the inner surface of the respirator body.

[0264] The method can be implemented such that the stack of sealing media layers includes sealing the pleated media layer to the outer surface of the respirator body.

[0265] The method can be implemented such that the stack of sealing media layers includes sealing the periphery of the pleated media layer to the respirator body.

[0266] The method can be implemented such that the seal includes sealing at least 30% of the pleated media layer to the respirator body.

[0267] The respirator can be configured such that at least 50% of the periphery of the nasal pad is sealed to the body.

[0268] The method may include: a preformed dielectric layer stack, wherein the preformation shapes the dielectric layer stack into a cup shape.

[0269] This method can be implemented such that one of the layers in a stack of dielectric layers includes a shell layer.

[0270] Methods may include adding one of a nose clip, nose foam, valve, or harness to a stack of media layers before or after sealing.

[0271] This method can be implemented such that the seal includes welding, spot welding, bonding or spot bonding, or the formation of a joint.

[0272] The method can be implemented such that the stack of media layers also includes one of a cover mesh, an adsorbent layer, a filter layer, or a shell layer.

[0273] This method can be implemented to make the respirator a horizontal three-fold respirator.

[0274] This method can be implemented such that the respirator is a vertically folding respirator.

[0275] This method can be implemented to make the respirator a cup-shaped respirator.

[0276] This method can be implemented to make the respirator a pleated respirator.

[0277] This method can be implemented to make the respirator a duckbill respirator.

[0278] The method can be implemented such that the pleated medium layer comprises: a first series of substantially parallel, non-bonded elastic filaments between a first nonwoven porous web and a second nonwoven porous web, and the first nonwoven porous web is directly bonded to the second nonwoven porous web.

[0279] The method can be implemented such that the wrinkled dielectric layer is a first wrinkled dielectric layer, and the stack of dielectric layers includes a second wrinkled dielectric layer.

[0280] The respirator can be implemented such that the first layer and the second layer have the same composition.

[0281] The respirator can be implemented such that the first layer has a different composition than the second layer.

[0282] The respirator can be implemented such that the first layer has a different thickness than the second layer.

[0283] Example

[0284] Adhesion test panel

[0285] Facial fit performance of Comparative Example (CE) 1 and Examples (EX) 1 to 3

[0286] Facial fit testing is used to determine the amount of leakage between a respirator user's face and the tightly fitting seal of the respirator. The amount of leakage through the facial seal between the respirator and the user's face can be quantified by measuring the concentration of test aerosols (e.g., NaCl particles suspended in the air) inside and outside the respirator. Available facial fit tests have been developed that selectively detect particles 60 nanometers (nm) or smaller. See U.S. Patent No. 6,125,845 to Halvorson et al. A commercially available instrument suitable for facial fit testing is the TSI PortaCount. ® Pro+ (TSI Inc., Shoreview, MN). Another suitable instrument is the TSI PortaCount. ® Plus N95-Companion ™ (TSI Company).

[0287] Eleven samples were prepared for each of CE 1 and EX 1 through 3 for facial fit testing on test subjects. CE 1 was a cup-shaped respirator, available under the trade name "3M Disposable Respirator 8210 Plus" from 3M Co., Maplewood, MN, USA. Figure 7A and Figure 7BAs shown. Sample EX1 was manufactured using a shaped pleated medium welded to the CE 1 respirator to form a facial seal. The facial seal material was W4-150 medium as specified in Table 2. The pleats in the facial seal medium were oriented parallel to the nose-to-chin direction on the respirator. Sample EX2 was manufactured using the same medium welded to the CE 1 respirator as the facial seal, wherein the pleats in the facial seal medium were oriented perpendicular to the nose-to-chin direction on the respirator. Sample EX3 was manufactured using two layers of the same W4-150 medium welded to the nasal area of ​​the CE 1 respirator to form a nasal pad. Figure 7E , Figure 7F , Figure 6A They respectively exhibit the configurations of EX 1, EX 2 and EX 3.

[0288] A sample probe holder (TSI Inc) was attached to each sample to allow determination of the aerosol concentration within the sample during facial fit testing. Eleven subjects with a range of facial length and width were selected. The measured facial length and width corresponded to the menton-sellion length and zygomatic distance, respectively, as described in Z. Zhuang et al., Novel Respirator Fit Test Panel Representing the Current US Civilian Workforce, *Journal of Occupational and Environmental Medicine*, 2007, 4:647-659. All subjects were tested using CE 1 and each of EX 1 through EX 3.

[0289] Facial fit testing was conducted in a test chamber (with filtered air ventilation) approximately 2.5m high × 2m wide × 1.5m deep. A TSI Model 8026 particle generator (TSI Inc., Shoreview, Minnesota) was used to generate a NaCl aerosol containing 2% NaCl (by weight / volume) in distilled water, with particles having an approximate count median diameter of 50 nm. The atomizer was adjusted to allow for the use of a PortaCount atomizer. ® The bonding test system, consisting of Plus and N95-Companion™, obtains readings from 500 particles / cc to 1,500 particles / cc in “count mode”.

[0290] For each fit test, the subject wears a sample respirator, enters the testing chamber, and attaches the respirator to the fit testing system via a sample probe and tubing. The subject is then asked to perform eight exercises, as defined in 29 CFR 1910, 134, Appendix A, Part IA14. During these exercises, particle concentration data are collected from the fit testing system using a microcomputer. Data can also be obtained without a microcomputer by running the fit testing system in “counting mode” and manually recording data from the fit testing system reader. Specific exercises, their duration, and data collection protocols are detailed below.

[0291] Table 3 shows the facial fit test practice and data collection. Start and end times were measured in seconds after the start of the practice.

[0292]

[0293] Fit factors were calculated for all exercises except for making faces. The fit factor was equal to the test chamber aerosol concentration divided by the internal respirator aerosol concentration. For each exercise, the test chamber aerosol concentration used was the average of the test chamber concentrations measured immediately before and after the internal respirator concentration. The mean fit factor for each subject wearing each sample respirator was obtained by calculating the harmonic mean of seven fit factors for the first normal breath, deep breath, head up-and-down movement, head left-and-right movement, rainbow message reading, waist bending, and the second normal breath exercise. The harmonic mean was obtained by calculating the reciprocal of the arithmetic mean of the inverses of the fit factors for each exercise. The results of facial fit tests using samples CE 1 and EX 1 to 3 are shown in Table 4 below:

[0294] Compared to comparative sample CE 1, nine out of eleven subjects showed significantly higher fit factors in Examples 1 to 3 of the present invention, indicating a significant reduction in facial seal leakage. Only two subjects (subjects 8 and 9) had lower fit factors in Example EX 1 than comparative sample CE 1. Only one subject (subject 9) had a lower fit factor in Example EX 2 than comparative sample CE 1.

[0295] Various modifications and alterations may be made to this invention without departing from its spirit and scope. Therefore, this invention is not limited to the above-described embodiments, but is subject to the limitations set forth in the following claims and any of their equivalents.

[0296] The present invention may also be practiced appropriately in the absence of any elements not specifically disclosed herein.

[0297] All patents and patent applications cited above, including those in the background section, are incorporated herein by reference in their entirety. In the event of any conflict or discrepancy between the disclosure in such incorporated documents and the foregoing specification, the foregoing specification shall prevail.

Claims

1. A disposable respirator, the disposable respirator comprising: The pleated medium layer, wherein the pleated medium comprises: A first series of substantially parallel non-bonded elastic materials between the first nonwoven porous mesh and the second nonwoven porous mesh, and The first nonwoven porous mesh is directly bonded to the second nonwoven porous mesh; and At least a portion of the folded medium is capable of elastic stretching under tension; and The bonding feature includes a wrinkled medium.

2. The respirator according to claim 1, wherein the fitting feature includes a nose pad.

3. The respirator of claim 2, wherein the nasal pad is sealed to the body of the disposable respirator, wherein the body includes the pleated medium layer.

4. The respirator of claim 3, wherein at least 10% of the periphery of the nasal pad is sealed to the body.

5. The respirator of claim 3, wherein the periphery includes a straight edge, and wherein the nose pad is sealed to the body along the edge.

6. The respirator of claim 2, wherein the pleated medium layer comprises a first pleated medium composition, and wherein the nasal pad comprises a second pleated medium composition different from the first pleated medium composition.

7. The respirator of claim 2, wherein the nasal pad comprises a first pleated medium having a first thickness, the pleated medium layer comprises a second pleated medium, and wherein the first pleated medium is thicker than the second pleated medium.

8. The respirator according to claim 2, wherein the nasal pad and the pleated medium layer have the same pleated medium composition.

9. The respirator of claim 3, wherein the nasal pad comprises a stretchable material such that the nasal pad at least partially recovers from a stretched state to a relaxed state, wherein the relaxed state includes the nasal pad being sealed to the respirator body, and wherein the stretched state includes applying tension to the nasal pad while it is being sealed to the respirator body.

10. The respirator of claim 9, wherein the nasal pad is configured to recover at least 50%.

11. The respirator of claim 9, wherein the nasal pad has an extended length in the stretched state, the extended length being 10% longer than the relaxed length in the relaxed state.

12. The respirator according to any one of claims 1 to 11, wherein the fitting feature includes a face seal.

13. The respirator of claim 12, wherein the face seal comprises an outer periphery and an inner periphery, and wherein the outer periphery is sealed to the respirator body.

14. The respirator of claim 12, wherein the disposable respirator has an inner surface, and wherein the face seal is configured to stretch to the extent that it contacts the inner surface of the respirator along the inner periphery of the face seal.

15. The respirator according to any one of claims 1 to 14, wherein the disposable respirator is a horizontally folding respirator, a cup-shaped respirator, a vertically folding respirator, a pleated respirator, or a duckbill respirator.

16. The respirator according to any one of claims 1 to 15, further comprising: Nose clips, nasal foam, valves, or harnesses.

17. The respirator according to any one of claims 1 to 15, wherein the respirator further comprises a strip, and wherein the strip is combined with the pleated medium layer to form an integral pleated medium article.

18. A disposable respirator, the disposable respirator comprising: A respirator body, the respirator body including a respirator filter layer; A nose clip, which is attached to the respirator body, the nose clip comprising a formable material; A face seal, the face seal being connected to the interior of the respirator body, the face seal including a corrugated medium; A strip, the strip being configured to pull the body of the respirator toward the wearer's face when the disposable respirator is worn.

19. The disposable respirator of claim 18, wherein the pleated medium comprises: A first series of substantially parallel, non-bonded elastic filaments between the first and second nonwoven porous webs; and The first nonwoven porous mesh is directly bonded to the second nonwoven porous mesh.

20. The disposable respirator of claim 18 or 19, wherein the pleated medium is a first pleated medium, and wherein the respirator filter layer comprises a second pleated medium.

21. The disposable respirator of claim 20, wherein the first pleated medium comprises a composition different from that of the second pleated medium.

22. The disposable respirator according to any one of claims 18 to 21, wherein the respirator filter layer comprises a flat medium.

23. The disposable respirator according to any one of claims 18 to 22, wherein the face seal comprises an outer periphery and an inner periphery, and wherein the outer periphery is sealed to the respirator body.

24. The disposable respirator of claim 23, wherein the outer periphery is sealed to the pleated medium layer.

25. The disposable respirator of claim 24, wherein the outer periphery is sealed to the shell.

26. The disposable respirator of claim 25, wherein the respirator includes an inner surface configured to receive the wearer's exhalation, wherein the face seal includes an inner periphery, and wherein the face seal is configured to stretch such that the inner periphery contacts the inner surface of the respirator.

27. The disposable respirator according to any one of claims 18 to 26, wherein the disposable respirator is a horizontally folding respirator, a cup-shaped respirator, a vertically folding respirator, a pleated respirator, or a duckbill respirator.

28. A method of manufacturing a respirator, the method comprising: A bonding feature is obtained, the bonding feature comprising a wrinkled medium layer, wherein at least a portion of the wrinkled medium is elastically stretchable under tension; A respirator body is formed, wherein the respirator body comprises a stack of media layers; The stack of the sealing medium layers is such that the respirator body is connected to the pleated medium layer.

29. The method of claim 28, wherein the fitting feature includes a nose pad.

30. The method of claim 29, wherein sealing the stack of the media layer comprises sealing the pleated media layer to the inner surface of the respirator body.

31. The method of claim 29, wherein sealing the stack of the media layer comprises sealing the pleated media layer to the outer surface of the respirator body.

32. The method of claim 30, wherein sealing the stack of the media layers comprises sealing the periphery of the pleated media layer to the respirator body.

33. The method according to any one of claims 28 to 32, wherein the fitting feature includes a facial seal.

34. The method of claim 33, wherein the face seal comprises a stretchable material such that the face seal at least partially recovers from a stretched state to a relaxed state, wherein the relaxed state includes the face seal being attached to the respirator body, and wherein the stretched state includes applying tension to the face seal while the face seal is attached to the respirator body.

35. The method of claim 33, wherein sealing the stack of the media layer comprises sealing the pleated media layer to the inner surface of the respirator body.

36. The method of claim 33, wherein sealing the stack of the media layer comprises sealing the pleated media layer to the outer surface of the respirator body.

37. The method of claim 33, wherein sealing the stack of the media layers comprises sealing the periphery of the pleated media layer to the respirator body.

38. The method of claim 37, wherein sealing comprises sealing at least 30% of the pleated medium layer to the respirator body.

39. The method according to any one of claims 28 to 38, further comprising: Preforming the stack of the dielectric layers, wherein the preforming forms the stack of the dielectric layers into a cup shape.

40. The method according to any one of claims 28 to 38, wherein the wrinkled dielectric layer comprises: A first series of substantially parallel, non-bonded elastic filaments between the first and second nonwoven porous webs; and The first nonwoven porous mesh is directly bonded to the second nonwoven porous mesh.

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