CN116867394A - Improvements relating to face masks - Google Patents

Abstract

A mask with improved stability includes a filtering face mask that includes a face mask having a sealing member depending from a mask body to engage a wearer's face, the mask body including a nose portion (27) for receiving the nose of the wearer, a mouth portion (26) for receiving the mouth of the wearer, and a cheek portion (28) extending laterally over the cheek of the wearer.

Description

Improvements relating to face masks

Technical Field

The present invention relates to a mask, a method of manufacturing a mask, and a mask produced by the disclosed method.

Background

Masks are used for a variety of reasons including treatment, and for personal protection (in both medical and non-medical applications).

Some masks require filtering particulate matter from the air, i.e., filtering masks. Such masks are typically one of two types. In particular, the mask may have a mask body that itself serves to filter out particulate matter from the air, and filtering masks of this type are generally lightweight and relatively inexpensive, and thus single-use and disposable. Alternatively, the mask may have a mask body adapted to receive the filter cartridge pieces. Such filter cartridge assemblies may be replaceable so that the mask can be reused.

The filtering face mask may be worn in a work or public environment to protect against dust, smoke and other toxic substances, and to protect against pathogens such as viruses or bacteria. For example, in a healthcare environment, filtering face masks are used to prevent inhalation of pathogens from the environment by preventing particles, such as droplets and aerosols, from passing through the face mask. The filtering face mask may also protect others from pathogens exhaled by the wearer.

Filtering face masks typically include a filter, such as a sheet of woven or nonwoven filter material, and include means for retaining the mask on the wearer's head, such as by elastic loops placed around the ears. In use, the filter covers the mouth and nose of the user, or air is otherwise directed through the filter such that any air inhaled by the wearer passes through the filter. To protect others from pathogens exhaled by the wearer, the filter may be arranged such that any air exhaled by the wearer passes through the filter.

A filtering face mask worn in a work environment, such as by a healthcare worker, must remain in close proximity to the face and be comfortable for long wear in environments where the risk of contamination may be high. Such a mask must closely conform to the face of the wearer and preferably form a seal against the face so that inhaled and exhaled air cannot bypass the edges of the mask.

Filter masks are typically single use products and are mass produced and sold. In order for this type of product to be commercially viable, manufacturing costs and complexity must be kept to a minimum.

In many cases, it is desirable for the mask to seal to the wearer's face to prevent air from entering or exiting around the perimeter of the mask. Forming an effective seal against different facial contours can be challenging and typically employs a cushion seal formed of an elastomeric material that compresses against the face to form a seal. However, such seals may move during facial movement of the wearer (e.g., during speech), and may be prone to lateral displacement on the face.

Disclosure of Invention

A mask and method for producing a mask that overcomes or substantially alleviates the above-identified and/or other problems associated with the prior art has now been developed.

According to an aspect of the present invention, there is provided a filtering face mask comprising a support frame, a filter, and a sealing member, wherein the sealing member is secured to the support frame and the filter.

The support frame and the filter may together define a mask body that forms a cavity for receiving the mouth and nose of a wearer. The mask body may be curved at least in a transverse plane.

The support frame may be made of a plastic material such as polypropylene, poly (styrene-butadiene-styrene) (SBS), polycarbonate, plastomer, thermoplastic elastomer, thermoset material, or a blend or combination of the foregoing.

The support frame may have an outer face portion and an inner face portion, the inner face portion facing the wearer in use and the outer face portion facing away from the wearer in use.

The support frame may support at least a portion of the filter, e.g., the support frame may support at least a portion of the filter to prevent deformation of the sheet of filter material. The support frame may provide rigidity to the mask. The support frame may hold the filter media at a distance from the face, thereby preventing direct contact of the filter media with the mouth and/or nose, and reducing or preventing degradation and contamination of the filter, and increasing the comfort of the wearer.

The support frame may take the form of a rim portion which matches the shape of the filter material piece, for example. The rim portion may have the form of a closed loop. The rim portion may define an aperture through which, in use, inhaled and/or exhaled gas flows. The support frame may extend around the periphery of the filter when the filter is placed on the support frame. The support frame may include a shoulder extending from the inner edge of the rim portion to provide a surface on which the filter may be positioned to assist in retaining the filter in the mold prior to injection molding of the sealing member. The filter may be located on an inner face of the support frame. The periphery of the filter may seal against the support frame such that air cannot flow between the edge of the filter and the support frame; the inhaled air must pass through the filter.

Instead of or in addition to the rim portion, the support frame may include one or more ribs, such as a plurality of ribs, configured to abut a surface of the filter to provide support for the filter and rigidity to the mask. The one or more ribs may have a shape corresponding to the shape of the surface of the filter. The one or more ribs may be shaped such that the one or more ribs extend over the surface of the filter. The one or more ribs may extend between the rim portion or the opposite sides of the support frame and be shaped to abut a surface of the filter. The one or more ribs may have an arcuate shape. Such ribs may provide structure and/or rigidity to the rim portion or support frame to help maintain the shape of the mask and prevent deformation of the filter material.

The outer portion of the support frame may further comprise a barrier portion, which in the filter mask according to the invention extends over at least a part of the surface of the filter. The barrier may be separate from the filter and may be positioned at the front of the filter such that air may flow between the barrier and the filter, for example during inhalation before air is inhaled by the wearer via the filter. Thus, there may be a space or void between the barrier and the filter. Inlet apertures through which air may be inhaled by the wearer's inhalation may be defined between the edges of the barrier and the surface of the filter. The barrier may not contact the filter.

The barrier may provide a barrier against which particles in the environment impinge. Thus, the barrier may reduce the amount of particles incident on the filter during use, and thus may extend the effective life of the filter and thus the effective life of the filter mask. The separation between the barrier and the filter enables the incoming air to flow through the filter over the entire surface of the filter, even if the barrier is impermeable or substantially impermeable. The barrier may also provide reinforcement to the mask, preventing the mask from collapsing longitudinally and maintaining the mask in the correct position relative to the nose and chin of the wearer.

The barrier may be formed from a plastics material. This may form a strong barrier to deflect particles and may reduce the risk of physical damage to the filter by providing a protective barrier. The barrier portion may form a rigid barrier portion.

Alternatively, the barrier may be a composite barrier formed from two or more components. The composite barrier may include a sheet of filter material (barrier filter) and a barrier frame, the barrier filter covering and being attached to the barrier frame. The barrier frame may be a plastic frame and may form part of the support frame. The barrier frame may include a barrier rim portion that is substantially the same shape as the intended barrier and/or barrier filter, the barrier rim portion being attached to the perimeter of the barrier filter. Such a composite barrier may actively absorb and block contaminants and may reduce moisture accumulation in the mask, thereby increasing wearer comfort. The composite barrier may be removably secured to the mask such that the composite barrier may be replaced when the composite barrier becomes saturated; the entire composite barrier may be removable and replaceable, or only the sheet of filter material may be replaceable.

In the following paragraphs, unless otherwise indicated, references to "barrier" refer to both a barrier formed of a plastic material and a composite barrier formed of a barrier frame and a barrier filter. In addition, unless otherwise specified, reference to "a filter" refers to a main filter, i.e., a filter held by a support frame, and reference to "a barrier filter" refers to a filter that forms part of a composite barrier.

The surface area of the barrier may be at least 50%, at least 60%, at least 70%, or at least 80%, or at least 90%, or at least 95% of the surface area of the filter. The surface area of the barrier may be up to 110% of the surface area of the filter, or up to 105% of the surface area of the filter, or up to 100% of the surface area of the filter, or up to 95% of the surface area of the filter. The barrier may extend over at least 50%, at least 60%, at least 70%, or at least 80%, or at least 90%, or at least 95%, or up to 100% of the surface area of the filter.

The barrier may extend over the entire surface area of the filter or may extend beyond the periphery of the filter such that the barrier overhangs the edge of the filter. Alternatively, the barrier may extend over less than 100% of the surface area of the filter such that a portion of the filter is exposed at the periphery of the barrier. Alternatively or in addition, the barrier may have openings formed therein through which the sheet of filter material is exposed, which may assist in air flow and assist in evenly distributing the particulate load across the filter. Alternatively, the barrier may not have an aperture, but rather form a continuous barrier. Thus, the barrier may comprise a continuous surface extending over a majority of the surface of the filter material member.

The support frame may include a barrier portion extending over at least a portion of the outwardly facing surface of the filter, and at least a portion of the perimeter of the barrier portion is separate from the support frame. One or more inlet apertures may be defined between the barrier portion and the support frame through which air is inhaled when the wearer inhales.

The support frame may also include one or more seal support members. The support frame may include one or more seal support members located at any location where the seal needs to be reinforced. The support frame may include one or more seal support members located in the chin region, nose region, and/or cheek region. In particular, the support frame may comprise one or more seal support members located in the chin area. The one or more seal support members may provide additional support to the seal and help prevent the seal from collapsing and improve fit. The one or more seal support members may extend outwardly from the support frame so as to abut the seal member, and the one or more seal support members may have a shape corresponding to a shape of a portion of the seal member that abuts the seal support member. The one or more seal support members may have an arcuate shape.

The at least one seal support member may be located in a chin area, and the chin area of the support frame may include the at least one seal support member hanging down. The at least one seal support member may include a protrusion extending outwardly from the support frame and may extend downwardly in a direction generally perpendicular to the support frame. The at least one seal support member may extend to the distal edge of the seal member or may extend over only a portion of the depth of the seal member. The at least one seal support member may be bonded to the seal and/or the seal may be overmolded to the seal support member during the overmolding process. The seal support member provides additional reinforcement in the chin area, helping to prevent the seal from collapsing in this area. This helps to improve and maintain the sealing properties.

The support frame is typically formed from a plastics material which retains the shape of the support frame in use. The support frame may comprise a rim portion, and/or a barrier portion or barrier portion frame, and/or one or more connection members, and/or one or more seal support members. Where multiple components are provided, the entire support frame may be integrally formed, such as by injection molding, or the support frame may be formed as two or more components that are joined together, such as by gluing, welding, or mechanical fastening. Thus, in case the support frame comprises a rim portion and a barrier portion or barrier portion frame, the rim portion and the barrier portion or barrier portion frame may be integrally formed in one injection moulding step, or the rim portion and the barrier portion or barrier portion frame may be formed separately before being chemically or mechanically bonded together.

The filter may be formed of a filter substrate that is sufficiently dense to prevent the passage of most airborne particles, such as dust particles, droplets, and aerosols. The mask of the present invention may filter out at least 80%, or at least 85%, or at least 90%, or at least 95% or at least 99% of airborne particles.

In the united kingdom and the european union, etc., the FFP standard specifies the requirements of filtering face masks as respiratory protection devices. The EN149 standard defines three stage filter efficiencies, FFP1, FFP2 and FFP3. The mask of the present invention may be, for example, an FFP3 mask, the FFP3 mask filtering out at least 99% of airborne particles at an air flow of 95L/min under EN149 standard, and a total inward leakage of less than 2%. The mask of the present invention may be an FFP2 mask, the FFP2 mask filtering out at least 94% of airborne particulates at a flow rate of 95L/min, and a total inward leakage of less than 8%. In the united states, the National Institute of Occupational Safety and Health (NIOSH) specifies an N95 rating for air filtration, and the mask of the present invention may be an N95 mask, meaning that the mask of the present invention can filter at least 95% of airborne particles.

Materials suitable for use as filter substrates are known in the art and any suitable material may be used for the filter material sheet in the present invention. For example, the filter may be a nonwoven material, an electrostatic material, a meltblown material, a spunbond material, a woven material, nanofibers, or a nanofiber web material, or formed from a glass fiber medium. The filter may include multiple layers to enhance the performance of the filter and increase the comfort of the wearer. Thus, the filter may comprise one or more layers selected from nonwoven materials, electrostatic materials, meltblown materials, spunbond materials, textile materials, nanofiber web materials, and/or nanofiber materials. For example, the filter may include layers of nonwoven materials, electrostatic materials, and meltblown materials, as well as woven layers, to increase the comfort of the wearer and to provide structure to the filter. The filter may be of any suitable configuration, for example, the surface of the filter may be smooth, for example the surface of the filter may be flat or planar, or the filter may be pleated. The filter (pleated or uncreped) may have a flat or planar area around the periphery of the filter to facilitate the overmolding process. The filter may also include one or more additives, such as an antimicrobial agent, to enhance the effectiveness of the filter in reducing or preventing the transmission of pathogens.

The use of pleated filters increases the surface area of the filter, thereby increasing the efficiency of the filter. Crimping a filter can increase the surface area by 5% to 50%, or 5% to 30%, or 10% to 20% as compared to a filter without pleats. For receiving the pleated filter, the shape of the support frame may correspond to the shape of the pleated filter, thereby ensuring a tight fit between the two components and preventing leakage. For example, in the case of a filter abutting a shoulder or rim on a support frame, the shoulder or rim may comprise a series of corrugations corresponding to corrugations in the filter such that: when the filter contacts the shoulder or rim, the corrugations nest with the pleats of the filter to ensure a snug fit. The filter may be formed with corrugations before the filter is located in the mold with the support frame and the sealing member is overmolded to secure the sealing member, support frame and filter together. Alternatively, compressing a filter without pleats (i.e., flat or planar) between a corrugated rim or shoulder of a support frame and a correspondingly shaped mold may form pleats in the filter prior to overmolding the sealing member to secure the sealing member, support frame, and filter together.

The filter in the mould in the method of the invention may comprise only the filter base and may be in flexible form. The filter may not include a support for the filter base until secured to the support frame and the sealing member.

The filter may be cut into the correct shape from a larger filter substrate sheet, for example using a die. When the filter is formed of multiple layers, the filter may be cut to size and sealed edges in a single hot stamping process, wherein heat is used to seal the peripheral portion of the filter during the cutting process. In use, the sealed peripheral edge prevents moisture or contaminants from entering the interior between the layers of the filter material. The size and shape of the filter may correspond to the size and shape of at least a portion of the support frame. For example, the size and shape of the filter may correspond to the size and shape of the rim portion of the support frame such that the filter may be positioned on the rim portion, e.g., on a shoulder extending inwardly from the rim portion, such that the support frame extends around the periphery of the filter.

In some embodiments, the filtering face mask may include a single filter. In some embodiments, the filtering face mask may include two or more filters. The filtering face mask may include a first filter located at a first side of the mask and a second filter located at a second side of the mask. Each of the first filter and the second filter may be in contact with the support frame before each of the first filter and the second filter is secured to both the support frame and the sealing member by over-molding the sealing member. In this embodiment, the support frame may include a housing having a first aperture and a second aperture, and the first filter and the second filter may be positioned in the first aperture and the second aperture. The size and shape of each filter may correspond to the size and shape of the associated aperture in the support frame such that the filter may be positioned on the support frame, for example on a shoulder extending inwardly from the periphery of the aperture such that the support frame extends around the periphery of each filter.

The sealing member may be shaped to closely conform to and seal against the face of the wearer such that all air inhaled by the wearer passes through the filter material. To increase comfort and sealing effect, the sealing member may be in the form of a bumper. That is, the sealing member may form an elastically compressible region between the support frame and the wearer's face, thereby increasing comfort and improving sealability.

Additives may be used to enhance the effectiveness of the mask in preventing the passage of pathogens. According to another aspect of the present invention, there is provided a filtering face mask comprising a support frame, a filter, and a sealing member, wherein the sealing member is secured to the support frame and the filter, and wherein at least a portion of the filtering face mask comprises one or more additives selected from the group consisting of antimicrobial agents, antiviral agents, and antifungal agents.

Any aspect of the support frame and/or seal and/or filter may include one or more additives including, but not limited to, antimicrobial, antiviral, and/or antifungal agents to help improve the effectiveness of the mask in reducing or preventing the transmission of bacteria or other pathogens. In particular, additives containing Silver ions (e.g., in Silver Knight ^TM Form) incorporated into the plastic of the support frame and/or the seal. Silver ions have been found to catalyze the inactivation of pathogenic bacteria and prevent the proliferation of pathogenic bacteria, thereby reducing microbial growth in and on the surface of the mask.

The sealing member, and thus the mask, may also extend laterally over the cheeks of the wearer such that a seal is formed between the mask seal and the tissue of the cheeks and the inner cavity of the mask extends over the cheeks.

During speech, most of the movement of the face, including vertical separation of the nose and chin, occurs in the chin, while the amount of movement of the cheeks is relatively small. In addition, the tissues of the cheek are softer and more compliant than the tissues of the nose or chin. This means: the sealing member requires a lower degree of flexibility than the rest of the face to achieve an effective seal with cheek tissue. Furthermore, sealing at a location remote from the mouth and mouth movement helps to provide stability and maintain a constant seal.

According to another aspect of the present invention there is provided a mask comprising a mask body defining a cavity for receiving, in use, a nose and mouth of a wearer and from which the wearer inhales breathing gas, and a sealing member depending from the mask body for engagement with the face of the wearer, the mask body comprising a nose portion for receiving the nose of the wearer, a mouth portion for receiving the mouth of the wearer, and a cheek portion extending laterally over the cheek of the wearer.

The sealing member may extend around the periphery of the mask such that the sealing member includes corresponding cheek portions that extend laterally over the cheeks of the wearer.

It has been found that the additional lateral stability provided when the mask body extends laterally over the cheeks of the wearer makes it easier for the user to position the mask correctly and helps prevent the mask from slipping to either side during use. This lateral stability and the resulting effective seal make the mask body and seal structure suitable for use in other types of masks, including gas delivery masks and gas delivery filtering masks (e.g., oxygen or aerosol delivery).

The cheek portion may extend over the cheek of the wearer between an upper edge of the cheekbone and a lower edge of the mandible of the wearer. The laterally extending cheek portions of the mask may form a portion of the mask having a longest dimension in a horizontal direction (i.e., a width direction, extending from a first side edge of the mask to an opposite side edge of the mask). The distance between the first side edge of the mask body and the opposite side edge of the mask body, measured along the surface of the mask body, may be between 1.2 and 2 times, or between 1.2 and 1.8 times, or between 1.3 and 1.7 times, or between 1.4 and 1.6 times the distance between the top edge of the mask body in the nose region and the bottom edge of the mask body in the chin region, measured along the surface of the mask body.

The first and second side edges of the mask in the cheek regions may include straight or substantially straight or linear edges. The first side edge and the second side edge may not be arcuate.

The cheek portions may each have a first edge that extends from a left or right edge of the nose portion such that the first edge of the cheek portion is received over the cheekbone of the wearer. The first edge may extend along an arcuate path. The first edge may be a concave outer edge. The transition between the first edge of the cheek portion and the left or right edge of the nose portion may be in the form of an arch.

The transition between the first edge (between the nose portion and the cheek portion) and the first side edge and/or the second side edge (in the cheek portion) may be angled. The transition between the first edge and the first side edge and/or the second side edge may be at an angle between 70 degrees and 110 degrees, or between 80 degrees and 100 degrees, or about 90 degrees.

The first side edge may connect the first edge and the second edge at a distal end of the cheek portion (e.g., near the wearer's ear). The second side edge may connect the first edge and the second edge at a distal end of the opposite cheek portion (e.g., near the other ear of the wearer).

The cheek portions may each have a second edge that extends from a left or right edge of the mouth portion such that the second edge of the cheek portion is received over a lower edge of the mandible of the wearer. The second edge may extend along an arcuate path. The second edge may be a concave outer edge. The transition between the second edge of the cheek portion and the left or right edge of the mouth portion may be in the form of an arch.

The transition between the second edge (between the mouth portion and the cheek portion) and the first side edge and/or the second side edge (in the cheek portion) may be angled. The transition between the second edge and the first side edge and/or the second side edge may be at an angle between 70 degrees and 110 degrees, or between 80 degrees and 100 degrees, or about 90 degrees.

The tangential angle between the tangent of the first edge and/or the second edge of each cheek portion and the x-axis may decrease with increasing lateral position. The angle between the tangents to the first and second edges of each cheek portion may decrease with increasing lateral position. The first and second edges may be substantially parallel at a distal end of the cheek portion, e.g., near the ear of the wearer. At the distal end of the cheek portion, the first edge may be generally horizontal and/or linear (extending in a direction across the wearer's face in use), while the second edge is arcuate or generally arcuate. The first side edge and/or the second side edge of each of the cheek portions may be substantially linear and may be aligned with the longitudinal axis (i.e., y-axis) of the mask. The distal region of each cheek portion may be generally rectangular in shape. This may increase the surface area of the mask body that covers the cheeks of the wearer.

The mask body may extend a greater distance in a lateral direction over the face of the wearer relative to the distance the mask body extends in a longitudinal direction over the face of the wearer. The greater distance may be in terms of the surface of the wearer's face, i.e., the distance may be the dimension along the surface of the face, rather than the linear dimension.

The mask body may extend a greater distance in the lateral direction relative to the distance the mask body extends in the longitudinal direction. The greater distance may be in terms of the face of the mask, i.e., the distance may be along or parallel to the face of the mask, rather than a linear dimension.

The nose portion and chin portion of the sealing member may seal against or around the nose and chin, while the cheek portion extends laterally over and seals against the cheek of the wearer. The chin portion may seal against the front of the wearer's chin or may seal under the chin. The chin portion of the sealing member may not extend below the mandible. The sealing member may not extend around the wearer's eyes and/or forehead.

The depth of the sealing member in the cheek portion may be less than the depth of the sealing member in the nose portion. The depth of the mask body in the cheek portion may be less than the depth of the mask body in the nose portion. Thus, the portion of the interior cavity formed by the cheek portion of the mask around the cheek may be shallower than the portion of the interior cavity formed by the nose portion and mouth portion of the mask around the nose and mouth. The portion of the interior cavity formed by the cheek portion of the mask around the cheek may have a smaller interior volume than the interior volume of the portion of the interior cavity formed by the nose region and the mouth region of the mask around the nose and the mouth.

The sealing member in the cheek region may comprise a first portion that extends rearwardly from the peripheral portion of the support frame in use, and a second portion. The first portion may include a proximal edge secured to the support frame and include a distal edge. The second portion may include an outwardly depending lip extending from the distal edge of the first portion. The second portion may define a face contacting surface. The outwardly depending lip of the second portion may extend from the distal edge of the first portion by a dimension of between 1mm and 10mm, or between 2mm and 6 mm. The thickness of the material forming the first portion may be greater than the thickness of the material forming the second portion. It has been found that the incorporation of an outwardly depending lip in the cheek region helps to form an effective seal in that region and to maintain such a seal even during facial movement.

At least a portion of the sealing member in the chin region may comprise a first portion and a second portion, the first portion extending rearwardly from the peripheral portion of the support frame in use. The first portion may include a proximal edge secured to the support frame and include a distal edge. The depth of the first portion may vary along the length of the first portion. The second portion may include both an inwardly depending lip and an outwardly depending lip, wherein the second portion is secured to the distal edge of the first portion. The second portion may define a face contacting surface. The outwardly depending lip of the second portion may extend from the distal edge of the first portion by a dimension of between 1mm and 20mm, or between 5mm and 20 mm. The inwardly depending lip of the second portion may extend from the distal edge of the first portion by a dimension of between 1mm and 15mm, or between 5mm and 15 mm. The thickness of the material forming the first portion may be greater than the thickness of the material forming the second portion.

The portion of the mask body that receives the nose and mouth of the wearer may have an outer surface that is generally arcuate in shape, e.g., in a transverse plane, while the portion of the mask body that receives the cheeks of the wearer may have an outer surface that is generally flatter in shape, e.g., in a transverse plane. The mask and the internal cavity of the mask may extend laterally over the cheeks of the wearer such that the edges of the mask lie within 5cm, or within 4cm, or within 3cm, or within 2cm of the wearer's ears in use. The mask may extend laterally over the cheeks of the wearer such that the edges or corner portions of the mask are positioned in use on or around the cheekbones, or on or around the zygomatic processes. Thus, the mask may substantially cover the cheeks of the wearer.

The mask body may include a sidewall that extends around at least a portion of the perimeter of the mask body. The side walls may form part of the support frame. The depth of the side wall in the nose region may be greater than the depth of the side wall in the cheek region to accommodate the nose of the wearer. The depth of the side wall in the nose region may be greater than the depth of the side wall in the chin region or cheek region. The depth of the sidewall in the chin area may be approximately the same as the depth of the sidewall in the cheek area. The cheek region may not include a sidewall.

The depth of the side wall may taper between the nose region and the cheek region such that the region of the side wall having the greatest depth is in the nose region and the region of the side wall having the smallest depth is in the cheek region. The depth of the sidewall may be substantially constant between the chin area and the cheek area. Where one or more seal support members are provided, the one or more seal support members may extend outwardly from the side wall, for example, the seal support members may extend outwardly from a central point in the chin area.

The first region of the side wall may extend between the nose region and the cheek region. The first region of the side wall may be generally arcuate in shape and may extend rearwardly from the rim portion of the support frame (i.e. towards the face of the wearer in use). At least a portion of the first region of the side wall may extend rearwardly from the rim portion of the support frame at an obtuse angle relative to the front face of the mask. The portion of the first region adjacent the nose region may extend outwardly at an obtuse angle relative to the front face of the mask. At least a portion of the first region of the side wall may extend rearwardly from the rim portion of the support frame at right angles to the front face portion of the mask, i.e. in a direction perpendicular to the front face portion of the mask. The portion of the first region adjacent the cheek region may extend rearwardly from the rim portion at right angles to the front face of the mask.

The second region of the sidewall may extend between the chin region and the cheek region. The shape of the second region of the sidewall may be a generally arcuate shape.

In the case where the mask is a filtering mask, the mask body may be defined by a support frame and a filter. The sealing member may extend around the periphery of the support frame, for example around the periphery of the rim portion. The shape of at least a portion of the support frame and the shape of at least a portion of the filter may correspond to the shape of the proximal edge of the sealing member. The support frame and filter may extend laterally over the cheeks of the wearer. The portion of the mask body extending over the cheeks of the wearer forms a chamber between the mask and the face of the wearer that is shallower than the chamber formed between the mask and the face of the wearer by the portion of the mask body extending over the nose and mouth of the wearer.

The extension of the mask over the cheeks increases the surface area of the sheet of filter material, thereby increasing the amount of air that can pass through the filter. At the same time, the shallower cavity in this region of the mask reduces dead space within the mask.

Embodiments in which the cheek portion extends laterally over the cheek of the wearer may be advantageous in therapeutic masks including, but not limited to: nebulizer masks, sleep apnea masks, CPAP masks, oxygen delivery masks, NIV masks, and aerosol masks. The amplitude (break) of the mask in the cheek regions provides a more stable fit over the wearer's face, making the mask less likely to move or be removed during use.

The mask according to this embodiment of the invention may be particularly advantageous in situations where the user is significantly moving, for example, for treating sleep apnea and for CPAP and non-invasive ventilation. In this case, the wearer is typically a patient who is likely to move and roll, and the low profile of the mask and increased stability provided by the lateral extension of the cheek portions allows the wearer to move more easily, even while sleeping, without removing the mask. Furthermore, the lateral extension of the seal on the cheek enables a good seal to be obtained with less force in this area for elderly patients or other patient groups who may lose some teeth. The seal may be overmolded onto the mask body or may be manufactured as a separate component attached to the mask body. Suitable materials for producing the mask body and the seal, and the suitability of these materials for overmolding, will be apparent to those skilled in the relevant arts (e.g., materials science). The mask may not include a filter. The mask may include a filter that may provide a controlled air leak at a particular pressure. Typically, a controlled leak in the mask will cause noise to the irritating wearer, and the use of a filter or other permeable material, such as a textile material, to provide a controlled leak will reduce or prevent noise.

The mask according to this embodiment of the invention may further comprise a connector for connection to the nebulizer. As described above, the cheek portion may extend laterally between the upper edge of the cheekbone and the lower edge of the mandible of the wearer. Nebulizers are cumbersome devices and the weight of the nebulizer may cause the mask to shift on the face. The lateral extension of the cheek portion provides stability, reducing or preventing mask displacement and improving sealing. The nebulizer mask may also include at least one filter. The nebulizer mask may include one filter or two filters. In the case of a nebulizer mask comprising two filters, the nebulizer mask may comprise a first filter at a first side of the mask and a second filter at a second side of the mask, and the connector for connecting to the nebulizer is located between the two filters. The support frame may include: a housing having a first opening and a second opening for receiving the two filters; and an integrally formed connector for connection to the atomizer.

Since the effectiveness of a mask increases with increased fit (and reduced leakage), it is useful to have such a mask: the mask can accommodate faces of different sizes and is effective even in situations where the wearer is moving and performing active actions, such as a filtering mask for use by healthcare professionals.

According to another aspect of the present invention there is provided a filtering face mask comprising a support frame and a sheet of filtering material, the support frame and sheet of filtering material defining a mask body adapted to provide a cavity around the mouth and nose of a wearer in use, and the filtering face mask comprising a sealing member depending from at least a portion of a peripheral portion of the mask body, the sealing member comprising an inwardly depending lip portion and an outwardly depending lip portion relative to the peripheral portion of the mask body.

The sealing member may extend around the entire peripheral portion of the mask body. The portion of the peripheral portion of the support frame around which the inwardly depending lip portion and the outwardly depending lip portion extend includes a chin portion. The inwardly depending lip portion may extend around a majority of the peripheral portion of the support frame. The inwardly depending lip portion may extend around only a portion of the peripheral edge portion of the support frame. The portion of the peripheral portion of the support frame around which the inwardly depending lip portion extends may comprise a chin portion and/or the portion of the peripheral portion of the support frame around which the inwardly depending lip portion extends may comprise a nose portion. The portion of the peripheral portion of the support frame around which the inwardly depending lip portion extends may not include cheek portions to facilitate removal of the seal from the mold. The portion of the peripheral portion of the support frame around which the inwardly depending lip portion extends may include cheek portions to provide improved sealing. The outwardly depending lip portion may extend around a majority of the peripheral portion of the support frame. The outwardly depending lip portion may extend around only a portion of the peripheral portion of the support frame, e.g., the chin and cheek areas. The nose portion of the sealing member may not include an outwardly depending lip portion.

It has been found that the utility of the above features is beyond its use in a filtering face mask and that seals having the above features can be applied to any face mask where an effective seal is required.

Accordingly, there is provided a mask comprising a sealing member depending from at least a portion of a peripheral portion of a mask body, the sealing member comprising a chin region, a nose region, and a cheek region intermediate the chin region and the nose region, and the sealing member comprising both an inwardly depending lip portion and an outwardly depending lip portion relative to the peripheral portion of the mask body, wherein the inwardly depending lip portion extends around the chin region and the nose region of the sealing member, and the outwardly depending lip portion extends around the chin region and the cheek region of the sealing member.

It is important that a good seal against the face is formed without increasing manufacturing costs and complexity. It has been found that while the inwardly depending lip portion provides a good seal against the face, manufacturing is hindered by the increased difficulty in removing the seal from the mold. By providing an inwardly depending lip portion in the chin area and nose area with the greatest shape/dimensional change, the seal is improved. Cheeks are generally flatter and formed of softer tissue and thus more easily form a good seal against the cheeks. Thus, only the outwardly depending lip portions in these areas are sufficient to provide a good seal while facilitating manufacture.

The inwardly depending lip portion may be in a generally planar form. The inwardly depending lip portion may take the form of an upstanding wall which follows the contour of the peripheral portion of the body. The inwardly depending lip portion may include a discontinuity therein which assists in deforming the inwardly depending lip portion.

At least a portion of the outwardly depending lip portion may have a contact surface that is concave in shape. The outwardly depending lip portion may be shaped to provide a table or shelf structure under the chin of the wearer. The outwardly depending lip portion may take the form of an upstanding wall which follows the contour of the peripheral portion of the body. At least a portion of the outwardly depending lip portion may be planar and encircle the face of the wearer, for example in the chin region and/or cheek region. The proximal portion of the outwardly depending lip portion may engage the chin of the wearer, while the distal portion of the outwardly depending lip portion flexes and extends below the chin of the wearer. The outwardly depending lip structure may be formed in the shape of a chin cup. In use, the chin cup may house at least a portion of a wearer's chin. The outwardly depending lip portion may be shaped to provide both a front lip portion and a lower lip portion.

The inwardly depending lip portion may contact a lower portion of the wearer's face, for example, the wearer's chin, to form a seal. In the case of a user having a greater facial height, the outwardly depending lip portion may fit snugly under the wearer's chin, thereby providing an additional seal. The outwardly depending lip portion may provide an alignment guide for placement of the mask on the face, and helps to maintain the mask in the correct position on the face during use, even when the chin is moving, for all wearers.

The peripheral edge of the support frame in the vicinity of the inner and outer lip portions may be shaped at a first radius in the chin area from a center point or area of the mask. The inwardly depending lip portion generally has an inner edge having a radius less than the first radius. The outwardly depending lip portion generally has an outer edge having a radius greater than the first radius.

The nose portion of the sealing member may include an inwardly depending lip portion that may have a convex surface for contacting the face of the wearer. The nose portion of the sealing member may include reinforcing structures, such as reinforcing structures on each side of the nose, or reinforcing structures around the entire nose region. It has been found that the stiffening structure in the nose region can provide stability to the mask, preventing inadvertent movement and/or collapse of the seal, while maintaining the lateral flexibility required to accommodate different face sizes to help form a reliable seal. This reduces unnecessary deformation of this area or unnecessary folding of the seal, thereby improving fit and making the mask easier to wear properly.

Such a filtering face mask may include cheek portions that extend laterally over the cheeks of the wearer, as in the previously described embodiments, and such a filtering face mask may include any of the features of this embodiment, the cheek portions extending laterally between the upper edge of the cheekbones and the lower edge of the mandible of the wearer. This increases the stability of the mask on the face.

According to another aspect of the present invention there is provided a mask comprising a support frame defining a mask body adapted to provide a cavity in use around the mouth and nose of a wearer, and a sealing member depending from at least a portion of a peripheral portion of the mask body and comprising a nose portion which in use forms a seal against or adjacent the nose of the wearer, the nose portion comprising at least one stiffening member.

The mask may be a filtering mask or a mask containing a filtering element. The mask may also include a sheet of filter material. The support frame and the sheet of filter material may together define a mask body adapted to provide a cavity around the nose and mouth of a wearer in use.

In use, the nose portion of the seal extends over and around the nose of the wearer, forming a seal in the nose region.

The at least one reinforcing member may be located on an inner wall of the sealing member. The at least one reinforcing member may be located on an outer wall of the sealing member. The at least one stiffening member may be located on both the inner wall and the outer wall of the sealing member. The at least one reinforcing member may be integrally formed with the sealing member, i.e., the at least one reinforcing member may be integrally formed with the sealing member by injection molding at the same time as the sealing member is formed.

The at least one stiffening member may include one or more ribs positioned on each side of the nose region of the sealing member such that: in use, one or more ribs are positioned on each side of the nose. The nose region may include 2, or 3, or 4, or 5, or 6, or 7, or 8 or more ribs positioned on each side of the nose region of the sealing member. Each of the one or more ribs may extend in a direction generally perpendicular to the mask body. Each of the one or more ribs may extend from an edge of the sealing member proximate the mask body and may extend to an edge of the sealing member distal from the mask body. Each of the one or more ribs may extend only over a central portion of the sealing member and may not reach one or both of the proximal and distal edges of the sealing member. Each of the one or more ribs may have a uniform depth or may have a depth that varies along its length, and the depth of each of the one or more ribs may be greater in the central region than in the end regions. Each of the one or more ribs may have a width of 0.5mm to 3mm, or 0.5mm to 2 mm.

The at least one stiffening member may comprise a corrugated region, and/or a fan-like region, and/or at least one ridge.

The at least one stiffening member may include a corrugated region on each side of the nose portion. The corrugated region may include a series of parallel ridges and grooves that provide increased rigidity to the affected region of the seal. The bellows may extend in a direction generally perpendicular to the mask body. The corrugations may extend from the proximal edge of the sealing member to the distal edge of the seal, or the corrugations may extend over only a portion of the side wall of the seal, such as only a central portion, and may not reach one or both of the proximal and distal edges of the sealing member. Each bellows may have a proximal end and a distal end, wherein the proximal end and/or the distal end of each bellows has a height that tapers to zero relative to the sealing member. Alternatively, the proximal and/or distal ends of each bellows may form discrete shoulders. The corrugated region may be located on an inner or outer surface of the sealing member. The bellows may include a thickened region of the sealing member. The thickened region may be located on the inner or outer surface of the sealing member. The thickened regions may extend through the wall of the sealing member or discrete thickened regions may be provided on both the inner and outer surfaces of the sealing member (which may or may not be aligned with each other) such that the discrete thickened regions are visible on both the inner and outer surfaces of the sealing member. Alternatively, the corrugations may be formed from the side walls of the sealing member such that the side walls of the sealing member are shaped to form the corrugations. Such corrugations may be seen on both the inner and outer surfaces of the sealing member. The side walls of the sealing member shaped to form the corrugations may have a uniform thickness.

The at least one stiffening member may include a fan-like region on each side of the nose portion. The fan-like region may include a series of undulations on the wall of the sealing member that are on the inner or outer surface of the sealing member. The fan may comprise a thickened region of the sealing member. The thickened region may be located on the inner or outer surface of the sealing member. The thickened regions may extend through the wall of the sealing member or discrete thickened regions may be provided on both the inner and outer surfaces of the sealing member (the discrete thickened regions may or may not be aligned with each other) such that the discrete thickened regions are visible on both the inner and outer surfaces of the sealing member. Alternatively, the fan may be formed from the side wall of the sealing member such that the side wall of the sealing member is shaped to form the fan. Such a fan may be visible on both the inner and outer surfaces of the sealing member. The side walls of the sealing member shaped to form the fan-like portion may have a uniform thickness. The fan may extend in a direction substantially perpendicular to the sealing member. The fan may extend from the proximal edge of the sealing member to the distal edge of the sealing member and through the inner or outer surface of the sealing member, or the fan may be formed within the wall of the sealing member such that the fan is visible on both the inner and outer surfaces. Alternatively, the fan may extend only over a central portion (e.g., sidewall) of the sealing member, and may not reach one or both of the proximal and distal edges of the sealing member. Each fan may have a proximal end and a distal end, wherein the proximal end and/or the distal end of each bellows has a height that tapers to zero relative to the sealing member. Alternatively, the proximal and/or distal ends of each fan may form discrete shoulders. The smooth profile of the fan-like region may provide the required stability while ensuring that the sealing member can be easily removed from the mould.

The at least one reinforcing member may comprise at least one ridge. The at least one ridge may be positioned on an inner surface, an outer surface, or both the inner and outer surfaces of the sealing member. The at least one ridge may comprise a thickened portion of the sealing member which extends circumferentially around the nose region or in a direction generally perpendicular to the sealing member. The at least one ridge may extend from the proximal edge of the sealing member to the distal edge of the sealing member, or the at least one ridge may extend only over a central portion of the sealing member, and may not reach one or both of the proximal and distal edges of the sealing member.

It has been found that a stiffening member extending in a direction generally perpendicular to the sealing member serves to support the wall of the sealing member, thereby providing a compliant cushion that reduces or prevents collapse of the sealing member in the nose region, and improving the overall seal formed by the sealing member. It has also been found that such stiffening members reduce or prevent inversion. The stiffening members may extend over a portion of the side wall of the mask, such as the central portion, and/or the stiffening members may extend to or near the proximal edge of the sealing member, and/or the stiffening members may extend to or near the distal edge of the sealing member. In the event that the stiffening member extends to or near the distal edge of the sealing member, it has also been found that the stiffening member may help fix the relative position of the distal and proximal portions of the sealing member, thereby reducing or preventing inversion of the seal during fitting and/or donning, and making proper donning of the mask simpler. The stiffening member may also extend toward the proximal edge of the sealing member or may extend near the proximal edge of the sealing member, thereby providing additional support.

Alternatively, the at least one stiffening member may be a thickened region in the nose region of the sealing member. The at least one stiffening member may comprise a thickened region which, in use, is located on either side of the nose region, i.e. on both sides of the nose. Alternatively, the at least one stiffening member may comprise a continuous thickened region extending around the nose region. The thickened region may comprise a narrower band extending along a central portion of the sealing member, or the thickened region may comprise substantially the entire side wall of the seal.

It is important that any additional features, such as reinforcing members, do not interfere with or prevent removal of the seal from the mold. Smaller and/or narrower raised features may be particularly difficult to remove from the mold and may require manual removal. Larger structures, such as corrugations, fans, ridges and thickened areas, are generally easier to remove from the mold using ejector pins without damage.

A mask according to the invention may comprise means for securing the mask to a wearer in use. Such means may comprise one or more straps or bands, such as elastic straps or bands, which are worn around the wearer's head to urge the filtering face mask against the wearer's face.

One or more of the strings or straps may be formed as a separate component and then attached to the filtering face mask by inserting through an aperture or slot and tying or sealing, or by bonding the strings or straps to the face mask. The string or strap may be bonded to the mask by an adhesive or chemical bond, or by over-molding. The string or belt may be worn over the ears of the wearer or around the back of the wearer's head. This may help prevent the mask from slipping off and/or lifting up from the wearer's face during use.

Two cords or straps may be provided to extend around each ear of the wearer, or around the back of the head, one over the ears of the wearer and one under the ears of the wearer. A single cord may be provided that extends around the back of the wearer's head.

Alternatively, a single cord may pass twice over the back of the wearer's head.

The elastic cord or band may include means for indicating that the desired fit has been achieved. The elastic cord or band may include indicia that indicate to the user that the desired fit has been achieved. The elastic cord or belt may include a dimensional guide. When a mask according to the present invention has been worn and adjusted to provide the correct fit, for example using a fit test, the user may use the indicia to adjust any additional mask to the correct size without the need for an additional fit test. .

Where the mask is a filtering mask, the mask may include openings in the filter. The aperture may provide a conduit through the filter or the aperture may comprise a further device, such as an exhalation valve, or the aperture may be adapted to receive a further device, such as an exhalation valve. The openings may bypass the filter material. The openings in the filter material piece may be mounted and/or sealed to the openings in the support frame, or the openings in the filter material piece may be mounted and/or sealed to the device mounted to the support frame. Further, during injection molding of the sealing member, the polymeric material injected into the mold to form the sealing member may engage with the filter and with the aperture in the support frame, or with a device mounted to the support frame, to seal the filter around the aperture or device.

The mask may include one or more vents or valves, such as exhalation valves. During use, the exhalation valve may enable exhaled air to escape from the filter mask without passing through the filter, thus reducing the heat and moisture retained by the filter. However, in situations where a filtering face mask is required to protect other people from pathogens exhaled by the wearer, for example in a healthcare environment, inclusion of an exhalation valve may be undesirable. The vent or valve may be located in the barrier portion or in the rim portion of the support frame. The valve may be inserted into an aperture in the barrier or rim portion, or may form part of the barrier or rim portion. In the event that the valve is inserted into or forms part of the barrier, the valve may also extend through the filter material piece, and the over-moulding step forming the sealing member may be used to additionally provide a seal between the valve and the filter material piece and/or a seal between the aperture in the support frame for receiving the valve and the filter material piece. In case the valve is inserted into or forms part of the rim, a part of the rim may be shaped to house the valve, for example in the chin area.

In the case of a valve, the injection molding step for forming the sealing member may also form the valve member. Thus, the sealing member and the valve member may be integrally formed. After molding of the sealing member/exhalation valve, the valve may be inserted through openings in the filter and barrier portions, or through openings in the rim portion. Tension between the valve and the surrounding material (barrier, filter or rim) biases the valve closed. This allows exhaled air to flow from the mask interior to the exterior, but prevents air from flowing in the opposite direction.

The support frame, e.g. the barrier and/or the filter, may be formed with an aperture to which the exhalation valve or the releasable cover may be fitted. The over-moulding step of forming the sealing member may be used to additionally provide a seal between the aperture in the support frame for receiving the valve or cover and the piece of filter material. For example, the releasable cover may be secured over the aperture with a snap fit or screw fit connection, the cover being removed and replaced with an exhalation valve when desired. This enables the production of a single mask that may or may not be used with an exhalation valve. The size of the opening will be a suitable size for attaching the exhalation valve and may have a diameter of 10mm to 50mm, or a diameter of 15mm to 40mm, or a diameter of 15mm to 30 mm. Typically, the diameter of the openings will be about 20mm.

The filtering face mask may also include a socket that may be used to connect the face mask to a tube to introduce gas into or remove gas from the face mask and/or wearer. Thus, the filtering face mask can be used as an oxygen delivery face mask or respirator, with the added protection that inhaled and exhaled air (in addition to the delivered oxygen) must pass through the filter. In the same way as the exhalation valve, the socket may be releasably attached to the aperture in the barrier portion and optionally to the aperture in the filter. The aperture may be sized to receive a socket having a diameter of 10mm to 50mm, or a diameter of 15mm to 40mm, or a diameter of 15mm to 30 mm. Alternatively, the aperture may be sized to receive a socket having a diameter of 2mm to 10mm, or a diameter of 2mm to 8mm, or a diameter of 4mm to 8 mm. Alternatively, the socket may be integrally formed with the barrier portion, or the socket may be integrally formed with another portion of the support frame.

The filtering face mask may include a filter and a gas inlet (e.g., a mouthpiece) and is suitable for use as a high concentration face mask, an oxygen face mask, a CPAP face mask, or a high flow face mask. Conventional masks for delivering high concentrations of oxygen require the attachment of a storage bag to the inlet to provide an oxygen reservoir for inhalation in the event that the patient breathes beyond what is met by the oxygen supply. It should be appreciated that the masks described herein having a greater internal volume may eliminate the need for additional storage bags when compared to conventional masks, particularly where the mask extends laterally over the wearer's cheeks. Furthermore, the need to control infection and contaminant transmission means that: it is highly desirable to include a filter to protect both the patient and the personnel providing treatment to the patient.

The filtering face mask may include a gas inlet (e.g., a socket) that extends through or is integrally formed with the support frame or the mask body, and a filter. The gas inlet and filter may be located in different parts of the support frame or mask body. The gas inlet and filter may be located in the first and second regions of the support frame or mask body. In use, the first region and the second region may be located on different sides of the nose and mouth of the wearer. The filter may be located in a first cheek region of the support frame and the gas inlet is located in a second cheek region of the support frame such that oxygen flows from the gas inlet to the filter, rushing through the mouth and nose of the wearer, thereby providing a continuous flow of oxygen and helping to expel exhaled gases.

The support frame or mask body may include a housing having a first aperture in which the filter may be received and a second aperture through which the gas inlet may be inserted. Alternatively, the gas inlet may be at least partially integrally formed within the support frame or mask body. It should be appreciated that the air reservoir held within the filtering face mask may eliminate the need for an additional storage bag. In addition, the need for an anti-asphyxia valve is reduced or eliminated, as in the event of a failure of the oxygen supply, the wearer may inhale ambient air through the filter. The elimination of a storage bag and anti-asphyxia valve reduces manufacturing complexity and cost.

Accordingly, there is provided a mask comprising a mask body defining a cavity for receiving a nose and mouth of a wearer and a sealing member depending from the mask body for engagement with the face of the wearer, the mask body comprising:

a) A filter located in a first region of the mask body and a gas inlet located in a second region of the mask body; and

b) A nose portion for receiving the nose of a wearer, a mouth portion for receiving the mouth of a wearer, and a cheek portion extending laterally over the cheek of the wearer.

The mask body may be transparent so that the wearer's face (particularly the lips) can be seen through the mask, thereby enabling early identification of respiratory problems.

Alternatively, the filtering face mask may not include a socket. Such filtering face masks may not be suitable for use as oxygen delivery face masks or respiratory face masks.

The filtering face mask may additionally or alternatively include an access port. For example, the filtering face mask may include an access port for an endoscope, nasal cannula, or high flow nasal cannula so that endoscopy may be performed or the cannula worn while still providing the patient and medical practitioner with the protection provided by the filtering face mask. A mask having cheek portions extending laterally over the cheek may be particularly advantageous for use as an endoscopic mask because: the additional stability provided by the lateral extensions reduces the need for additional headgear to stabilize the endoscopic mask. The drug or oxygen may be delivered through a high flow nasal cannula and this type of treatment is characterized by: aerosolized particles may be generated and released into the environment. Depending on the nature of the patient's disease, such aerosolized particles may contaminate and risk nearby persons. Thus, wearing a filtering mask that allows access to the airway to deliver a high flow of nasal cannula, but that accommodates any aerosol generated, provides a safer environment for the clinician and other personnel in the vicinity. The access port may include an aperture in the filtering face mask. The apertures may include pairs of apertures in a support frame, such as a barrier, and a sheet of filter material, the pairs of apertures being aligned with one another such that a cannula may pass through both apertures. The over-molding step of forming the sealing member may be used to additionally provide a seal between the openings in the support frame and the openings of the filter material. The openings in the support frame, barrier and/or filter material may be provided with removable covers so that these openings may be covered when not in use.

In use, a wearer of the mask may exhale exhaled air into the internal cavity. Thus, a mask according to the present invention, which may be a filtering mask, may also include a device for detecting CO in exhaled air ₂ Concentration sensors, such as those described in GB2019236.5 (GB 2019236.5, incorporated herein by reference).

In this embodiment, the mask body and/or support frame may be formed of an IR transparent material. The sensor may be mountable relative to the sensor portion of the mask. The sensor may be an emitter of electromagnetic radiation and a receiver of electromagnetic radiation, wherein the enclosure wall of the mask body has a sensor portion comprising a first sensor window portion and a second sensor window portion, a portion of the interior cavity defined by the enclosure wall being defined between the first sensor window portion and the second sensor window portion, and the sensor is mounted relative to the sensor portion of the respiratory mask such that, in use, electromagnetic radiation from the emitter is emitted through the first sensor window portion of the sensor portion of the enclosure wall, through the portion of the interior cavity defined between the first sensor window portion and the second sensor window portion, through the second sensor window portion, and to the receiver. A mask with a sensor as described above may be advantageous because: the sensor portion formed in the enclosure wall of the mask body allows the sensor to monitor the patient's exhaled gas before it exits the mask body, thereby reducing the delay between the gas being exhaled and the measurement being taken. In contrast, with conventional respiratory masks that are connected to a sensor via an exhalation tube or sampling tube, the exhaled gas exhaled by the wearer must travel from the respiratory mask to the sensor, e.g., a respiratory monitoring unit, before the exhaled gas exhaled by the wearer can be monitored.

"each of the first sensor window and the second sensor window may have an inner surface and an outer surface. The sensor may be mounted relative to the sensor portion of the respiratory mask, wherein the transmitter is disposed adjacent an outer surface of the first sensor window and the receiver is disposed adjacent an outer surface of the second sensor window. "

The electromagnetic radiation "emitted by the emitter and received by the receiver may be infrared radiation. Infrared radiation may refer to radiation having a wavelength between about 700nm and about 1 mm. "

The first sensor window and the second sensor window may transmit electromagnetic radiation emitted by the emitter. For example, the first sensor window and the second sensor window may transmit infrared radiation, i.e. may transmit radiation having a wavelength between about 700nm and about 1 mm. The first and second sensor window portions may also transmit other wavelengths of light, such as visible light. The first sensor window and the second sensor window may transmit electromagnetic radiation emitted by the emitter to a greater extent than with respect to the mask body, the enclosure wall of the mask body, and the remainder of any one or any combination of the sensor portions. "

"the first sensor window and the second sensor window may transmit at least 50%, 60%, 70%, 80%, 90% or 100% of the electromagnetic radiation emitted by the emitter. To obtain accurate and/or viable readings, the sensor may require: a minimum amount of electromagnetic radiation, or a minimum proportion of electromagnetic radiation emitted by the transmitter, is received by the receiver. Thus, the first and second sensor window portions may transmit electromagnetic radiation emitted by the emitter such that at least 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90% of the electromagnetic radiation is received at the receiver after passing through a portion of the internal cavity defined between the first and second sensor window portions. "

"the first sensor window portion and the second sensor window portion may have a reduced thickness relative to the mask body, the enclosure wall of the mask body, and the remainder of any one or any combination of the sensor portions. The first sensor window and the second sensor window may have a thickness of up to 0.5mm, up to 0.4mm, up to 0.3mm, up to 0.2mm, up to 0.1mm, or up to 0.05 mm. The thickness of the first and second sensor window portions may refer to a distance between an inner surface and an outer surface of each sensor window portion. "

The inner surfaces of the "first and second sensor window portions, for example, the first and second sensor window portions, may be spaced apart by a distance between 2mm and 50mm, or a distance between 5mm and 30mm, that is, a portion of the internal cavity defined between the first and second sensor window portions may have a distance between 2mm and 50mm, or a distance between 5mm and 30 mm. "

Alternatively, the mask may be configured such that the sheet of filter material is replaceable. This means: the entire mask need not be replaced after use, but rather only the filter material, and the mask frame including the support frame and seal may be reused multiple times. This reduces both costs and waste.

The mask with replaceable filter according to this embodiment may be produced using the same principles as have been previously described and in a method involving a single over-molding step to fix the relative positions of the support frame and the seal.

According to another aspect of the present invention, there is provided a method for manufacturing a filtering face mask comprising a support frame having a housing for receiving a filter, and a sealing member, wherein the method comprises:

a) Providing a support frame in the mold; and

b) Injecting a polymeric material into the mold to form a first sealing member for sealing against the face of the wearer and a second sealing member for sealing against a filter received by the housing,

wherein the sealing member is engaged with the support frame during injection molding of the sealing member to secure the sealing member to the support frame.

According to another aspect of the present invention, there is provided a filter mask manufactured according to the above method. A filter mask is also provided that includes a support frame that further includes a housing for receiving a filter, and a sealing member, wherein the sealing member is secured to the support frame. Any of the features described above or below in connection with the filtering face masks of the present invention may be present in this embodiment, including but not limited to: a barrier section; and/or laterally extending cheek portions; and/or one or more reinforcing members; and/or a sealing member comprising an inwardly depending lip portion and an outwardly depending lip portion; and/or include a valve or an access port; and/or a plurality of filters.

The filter may comprise only a filter base which may be releasably attached to the support frame by any suitable means, for example, the filter base may be releasably attached to the support frame by clamps, or by an interference fit, or by a releasable adhesive, for example an adhesive tape covered by a releasable liner which is removed before the filter material sheet is inserted immediately.

Alternatively, the filter may include a filter base held within a cartridge or other support that is connectable to a support frame. For example, the cartridge may be connected to the outer surface of the support frame by one or more snap-fit connectors, or clamps, or by friction fit, or ports may be provided in the support frame for receiving the cartridge. In this embodiment, and where the mask includes a barrier portion, the barrier portion may form part of the cartridge or other support such that when the cartridge is attached to the outer surface of the mask, the barrier portion is positioned on the outer surface of the filter, at least a portion of the perimeter of the barrier portion being separate from the support frame. Alternatively, the barrier may be hingedly attached to the support frame such that the barrier may be opened to allow the filter cartridge piece to be inserted adjacent the outer surface of the support frame and then closed. The filter cartridge pieces may be held in place by one or more clamps or other attachment members, or an hingedly attached barrier may hold the filter cartridge pieces in place.

Alternatively, the filter cartridge members may be connected to the inner surface of the support frame by one or more snap fit connectors or clamps. In this embodiment, the barrier (if present) may be provided as shown in the figures and as described previously. For example, the filter mask may comprise a barrier portion which extends over at least a portion of the outwardly facing surface of the filter in use, at least a portion of the perimeter of the barrier portion being separate from the support frame and/or the barrier portion being integrally formed with the support frame.

The cartridge may take the form of a rim made of plastic, such as injection molded plastic, that matches the shape and size of the filter base and is secured around the circumference of the filter base. At least a portion of the cartridge may be overmolded around the circumference of the filter base. Alternatively, the entire cartridge may be overmolded around the periphery of the filter base. Thus, the cartridge does not restrict the flow of air through the filter base.

Methods for manufacturing the sealing member are known in the art, and any suitable method may be used in combination with the present invention. In particular, the sealing member may be manufactured at least in part using a gas-assisted injection moulding process as described in WO2021/037768 and GB2013108.2 (both of which are incorporated herein by reference). These documents describe the use of gas-assisted injection moulding in the manufacture of sealing members for respiratory devices. A filter mask for personal protection needs a very effective seal and it has surprisingly been found that a sealing member can be produced by this method which provides the required efficient seal in a filter mask.

According to another aspect of the present invention, there is provided a method of manufacturing a sealing member for use in a filtering face mask, the method comprising the steps of:

(a) Providing a mold having a cavity, a polymer injection port, and a gas inlet port;

(b) Injecting a polymer into a cavity of a mold through a polymer injection port; and

(c) Gas is introduced into the cavity of the mold through the gas inlet port,

thereby forming a sealing member of the filtering face mask, wherein at least a portion of the sealing member of the filtering face mask comprises an interior chamber at least partially defined by an elastically deformable enclosure wall formed of a polymer, the enclosure wall comprising a face contacting surface having a shape defined by a cavity of a mold and providing an anatomical fit to a user.

It has been found that when used to manufacture at least a portion of the sealing member of a filtering face mask, the outer surface of the elastically deformable enclosure wall may be shaped to provide an anatomically conforming shape to the wearer or face of the wearer, thereby providing the sealing member with effective sealing properties, while the interior chamber defined by the enclosure wall is also capable of urging the sealing member against the wearer, for example against the wearer's face, if improved sealing is desired. An effective seal is particularly important for filtering face masks because: in the event of a leak, the air will bypass the filter and the mask will lose efficacy.

According to the above method, only a part of the sealing member can be produced. The use of the above-described method to produce the nose region of the sealing member of a filtering face mask is particularly advantageous.

It should be understood that any feature described in relation to one aspect of the invention may be applied to any other aspect of the invention. Thus, any of the structural features described with respect to a mask having an integral filter, such as the shield, the first and second attachment structures, the exhalation valve, and/or the mouthpiece, may be applied to a mask having a replaceable filter as described above.

Drawings

Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings:

fig. 1 is a perspective view of a support frame of a filtering face mask according to the present invention;

FIG. 2 is a side view of the support frame of FIG. 2;

FIG. 3 is a perspective view of a filter of a filtering face mask according to the present invention;

fig. 4a is a perspective view of a filter positioned within a support frame of a first embodiment of a filter mask according to the present invention during manufacture;

FIG. 4b is the view of FIG. 4a without the filter;

FIG. 5 is a perspective view of the support frame and filter of FIG. 4 and the core of a mold used during manufacture of a first embodiment of a filter mask according to the present invention;

FIG. 6 is a side view of a filtering face mask according to the present invention;

FIG. 7 is a rear perspective view of a filter mask according to the present invention;

FIG. 8 is a schematic diagram showing the connection between a support frame and a piece of filter material formed by over-molding a sealing member;

fig. 9a and 9b are front and rear perspective views of another embodiment of a filtering face mask according to the invention;

fig. 10a and 10b are front and rear perspective views of another embodiment of a filtering face mask according to the invention;

FIG. 11 is a rear perspective view of a filter mask according to another embodiment of the invention;

fig. 12a and 12b show front and rear perspective views of a filter mask according to another embodiment of the present invention;

figures 13a to 13d illustrate a mask according to the present invention having stiffening members on each side of the nose region; and

fig. 14 shows a configuration of stiffening members that may be present in a mask according to the invention.

Detailed Description

A support frame 10 for use in a filtering face mask according to the present invention is shown in fig. 1 and 2. The support frame 10 has a substantially curved shape and includes an integrally formed rim portion (rim) 11, a barrier portion 12, a pair of first attachment structures (formations) 13, and a pair of second attachment structures 14. The shape of the barrier portion 12 is substantially the same as the shape of the rim portion 11, but the barrier portion 12 is smaller than the rim portion 11, and the barrier portion 12 is offset from the rim portion 11 by about 1cm. The barrier portion 12 is attached to the rim portion 11 by four connecting members 16, the four connecting members 16 being equally spaced around the circumference of the rim portion and the four connecting members 16 being attached to the barrier portion at points near the rim. The space 15 between the barrier portion 12 and the rim portion 11 extends around the periphery of the barrier portion and is only interrupted by the connecting member 16. The seal support member 31 extends downward from a central portion of the bottom edge of the rim portion 11. The seal support member 31 is an arcuate shaped projection that depends downwardly from the rim portion 11 and curves toward the rear of the support frame 10. The support frame 10 is an integrally formed component, all features of the support frame 10 being manufactured in a single injection molding step.

Extending outwardly from a first side of the rim portion 11 are pairs of first attachment formations 13, the pairs of first attachment formations 13 being positioned in use adjacent a first ear of a wearer. The first attachment structure 13 takes the form of a key-hole slot through which a string or strap (not shown) may be passed and secured by a knot or clamping device.

Extending outwardly from the second side of the rim portion are pairs of second attachment formations 14, the pairs of second attachment formations 14 being positioned in use adjacent the second ear of the wearer. The second attachment structure 14 comprises a groove (not visible) covered by the protrusion 17. The tab 17 has a series of teeth 18 that provide a grip. A rope or belt (not shown) passes from the inside of the support frame through the slot in the attachment structure 14 to the outside of the support frame between the protrusion 17 and the edge of the slot. The teeth 18 grip the cord and reduce or prevent movement of the cord in the opposite direction.

In use, the rope or strap is secured in the upper first attachment structure 13, from inside through the upper second attachment structure 14 to outside, from outside through the lower second attachment structure 14 to inside, and finally secured in the lower first attachment structure 13. Thus, the strap passes twice behind the wearer's head, forming a loop on the outside of the support frame and between the pair of second attachment structures 14. When the wearer applies tension to the ring, for example by pulling on the ring, the string will be pulled through the aperture past the teeth 18 on the tab 17. This release of tension, for example by the wearer releasing the loop of the cord, will allow the teeth 18 to grip the cord, preventing the cord from sliding back through the slot unless a significant force is applied. In this way, the mask can be easily adjusted with one hand to fit the wearer's head.

The support frame 10 is produced using injection molding, the support frame 10 being an integrally formed unit produced in a single step from injection molded polypropylene.

In the case of an automated manufacturing of the filtering face mask, the support frame 10 is ejected from the mold onto a vacuum chuck on a robotic arm. The pneumatic die pushes the sheet 22 of filter material from the roll of filter material into the support frame 10, the roll of filter material comprising a continuous series of pre-punched sheets of filter material heat sealed around a peripheral portion thereof. The sheet of filter material 22 is shown in fig. 3.

The sheet of filter material is positioned on the inner side of the support frame 10, i.e. the side of the support frame 10 that will face the wearer in use. The sheet of filter material is positioned on an inwardly extending shoulder and is held in place around the periphery of the shoulder by retaining tabs 19 at the sides of the rim. The support frame/filter material assembly is shown in fig. 4a and 4 b.

The support frame/filter material assembly is transferred into the first half of the mold and mounted to the mold core 30. The second half of the mold is sealed against the first half of the mold, thereby forming a mold cavity. In the injection molding step, the sealing member 25 is over-molded to the support frame/filter material assembly so as to surround the periphery of the filter material sheet 22 and adhere the filter material sheet 22 to the support frame 10, and the sealing member 25 is formed in a single over-molding step. The filter mask 20 is removed from the mold, such as by peeling the filter mask 20 from the core 30 using a larger pin of 20mm, and the filter mask 20 is transferred to manually attach the elastic cord and then packaged.

The connection between the filter, the sealing member and the support frame is schematically shown in fig. 8. The periphery of the filter 91 is placed against a shoulder 94 extending laterally from the rim portion of the support frame 93 before or after the support frame is placed in the mold. Thermoplastic elastomer (TPE) 92 is injected into the mold to form the sealing member. The portion of TPE92 shown in fig. 8 represents only the proximal edge of the sealing member. TPE92 is pressed between the peripheral edge of filter 91 and the rim and shoulder 94 of support frame 93 by a die. TPE92 surrounds the peripheral portion of filter 91 and impregnates the peripheral portion of filter 91, adhering filter 91 to rim portion and shoulder 94 of support frame 93, the impregnated area of the periphery being indicated at 95. As shown in fig. 8, the tool closure prevents TPE92 from entering filter 91 beyond the periphery 95 of the filter, thereby ensuring that the filtering action of filter 91 is not inhibited by TPE. In addition to helping the support frames 93, 94 adhere to the filter, impregnating the peripheral edge portion 95 of the filter 91 with TPE may also help form a seal at the edges of the filter by heat sealing, thereby preventing moisture or other contaminants from penetrating into the structure of the filter.

In fig. 6, a side view of a filter mask 20 according to the present invention is shown. The support frame 21 is the same as the support frame described in relation to fig. 1 and 2. The sheet 22 of filter material is positioned behind the support frame 21 and is visible around the periphery of the barrier portion 23 in the gap between the barrier portion 23 and the rim portion 24. This allows air to easily flow through the barrier 23 and through the filter material 22 while still benefiting from the barrier's protection of the entire filter material piece.

The sealing member 25 is over-molded to the support frame 21 and the filter material 22 so as to fix the relative positions of the support frame 21 and the filter material 22. The sealing member 25 includes a chin engaging portion 26, a nose engaging portion 27, and a cheek engaging portion 28. Cheek engagement portions 28 extend laterally over the cheek to form a seal against softer skin on the cheek and improve the overall seal of the mask.

The sealing member 25 is formed of an elastomeric material. The sealing member 25 provides a compressible area between the support frame 21 and the wearer's face, enabling the elastomeric material to conform to the contours of the wearer's face and providing a good seal against the wearer's face.

The downwardly depending seal support member 31 abuts the seal in the chin area, thereby enhancing the seal in this area and enhancing the seal against the wearer's chin.

Fig. 4a and 4b show a support frame/filter member assembly with filter material and a support frame/filter member assembly without filter material, respectively. The support frame 10 includes a rim portion 11. The rim portion 11 has an inwardly extending shoulder 41 on which shoulder 41 the pre-cut piece 22 of filter material is placed. A first attachment structure 13 extends from a first side of the rim and a second attachment structure 14 extends from a second side of the rim. The support frame 10 further includes a barrier portion 12. A series of vertical ribs 29 on the back of the barrier 12 ensure: the spacing between the barrier 12 and the filter material 22 is maintained.

Another embodiment of a filtering face mask in accordance with the present invention can be seen in fig. 9a and 9b and is indicated generally at 100. The construction of the mask is substantially the same as that described in relation to the first embodiment depicted in figures 6 and 7, except that the mask 100 also includes a mushroom valve 101 (shown in a closed position). In the chin area, the rim portion 102 of the support frame includes an upward protruding portion 103, and the shapes of the barrier portion 104 and the filter material member 105 correspond to the shape of the inner periphery of the rim portion 102, so that the barrier portion 104 and the filter material member 105 are accommodated in the upward protruding portion 103. The filter material piece 105 is sealed by the peripheral rim portion of TPE106 along the periphery of the rim portion 102 of the support frame including the upwardly projecting portion 103. The upwardly protruding portion includes an aperture in which the spool valve 101 is formed as part of an over-molding step that also forms the sealing member 107. The mushroom valve 101 allows exhaled air to escape without passing through the filter material 105. The mushroom valve 101 may alternatively be housed within the barrier 104.

Another embodiment of a filtering face mask, indicated generally at 110, shown in fig. 10a and 10b has substantially the same structure as described in relation to the second embodiment of fig. 9a and 9b, but shows an elbow connection 111 instead of a mushroom valve. Elbow connection 111 allows mask 110 to be connected to other medical devices such as a nebulizer.

Another embodiment of the filtering face mask of the present invention is shown in fig. 11. The filtering face mask has all of the features described with respect to fig. 6 and 7, but the filtering face mask also includes a series of corrugations 121 at each side of the nose of the sealing member to provide reinforcement to the seal. The bellows 121 extends in a direction perpendicular to the support frame and extends over a central portion of the seal. The corrugation 121 is integrally formed in the wall of the sealing member such that the corrugation 121 is visible from both the inside and the outside of the sealing member.

Fig. 12a and 12b depict a filtering face mask 140, the filtering face mask 140 comprising a filter 141, a gas inlet 142, a mask body 143, a sealing member 144 depending from the periphery of the mask body 143, and a pair of first attachment members 145 and a pair of second attachment members 146 as described with respect to fig. 4 a-4 b. The gas inlet 142 may be a socket. The aperture in the first side of the mask body 143 accommodates the filter 141, while the gas inlet 142 is inserted through or integrally formed with the second side of the mask body 143 such that: in use, the filter 141 and the gas inlet 142 are located on different sides of the nose and mouth of the wearer. During use, oxygen flows from gas inlet 142 to filter 141, rushing across the mouth and nose of the wearer, providing a continuous flow of oxygen and helping to expel exhaled gases.

Fig. 13 b-13 d show cross-sections of the mask 150 taken along line X-X marked on fig. 13 a. These figures show the stiffening member in the nose region.

Fig. 13b shows a series of ribs 151 on either side of the nose region of the sealing member 152. The rib 151 extends in a direction perpendicular to the mask body and is located on an inner side wall of the sealing member 152. The ribs provide reinforcement to the sealing member 152, thereby preventing deformation of the sealing member 152 in the nose region.

Fig. 13c and 13d show reinforcing members 153, 154 integrally formed within the wall of the sealing member 152. The stiffening members 153, 154 take the form of corrugations or scallops in the side walls of the sealing member, each corrugation 153 or scallop 154 extending in a direction perpendicular to the mask body. The wall of the sealing member 152 maintains a uniform thickness in the region of the reinforcing members 153, 154. The reinforcement members 153, 154 support the sealing member 152 in the nose region. Other arrangements of stiffeners are shown in fig. 14.

Claims (43)

1. A mask, the mask comprising: a mask body defining a cavity for receiving, in use, a nose and mouth of a wearer and from which the wearer inhales breathing gas; and a sealing member depending from the mask body for engagement with the face of the wearer, the mask body including a nose portion for receiving the nose of the wearer, a mouth portion for receiving the mouth of the wearer, and a cheek portion extending laterally over the cheek of the wearer.

2. The mask of claim 1, wherein the cheek portion is configured to extend laterally over the cheek of the wearer between an upper edge of a cheekbone and a lower edge of a mandible of the wearer.

3. A mask according to claim 1 or claim 2, wherein the mask extends laterally over the cheeks of the wearer such that: the edge of the mask being located within 5cm of the wearer's ear in use; alternatively, the edge of the mask is located within 4cm of the wearer's ear in use; alternatively, the edge of the mask is located within 3cm of the wearer's ear in use; alternatively, the edge of the mask is located within 2cm of the wearer's ear in use.

4. A mask according to any one of claims 1 to 3, wherein the distance between a first side edge of the mask body and an opposite side edge of the mask body measured along a surface of the mask body can be between 1.2 and 2 times the distance between a top edge of the mask body in the nose region and a bottom edge of the mask body in the chin region measured along the surface of the mask body.

5. A mask as claimed in any one of claims 1 to 3, wherein the mask substantially covers the cheeks of the wearer.

6. A mask according to any preceding claim, wherein the portion of the mask body extending over the cheeks of the wearer forms a chamber between the mask body and the face of the wearer that is shallower than the chamber formed between the mask body and the face of the wearer by the portion of the mask body extending over the nose and the mouth of the wearer.

7. The mask according to any one of claims 1-5, wherein the cheek portions each have a first edge that extends from a left or right side edge of the nose portion and is received on the cheekbone of the wearer and a second edge that extends from a left or right side edge of the mouth portion such that the second edge of the cheek portion is received on a lower edge of the jawbone of the wearer, wherein an angle between a tangent to the first edge and a tangent to the second edge of each cheek portion decreases with increasing lateral position.

8. The mask of claim 7, wherein the cheek portions each further comprise a side edge that extends between a distal end of the first edge and a distal end of the second edge.

9. The mask of claim 8, wherein the side edges comprise substantially linear edges.

10. The mask of claim 8 or 9, wherein an angle between the side edge and the first edge is between 70 degrees and 110 degrees.

11. The mask according to any one of claims 7-10, wherein the first edge is concave in shape.

12. The mask according to any one of claims 1-11, wherein the mask is a filtering mask and the mask body is defined by the support frame and a filter.

13. The mask of claim 12, wherein the sealing member extends around a perimeter of the support frame.

14. A mask according to claim 12 or claim 13, wherein the support frame and the filter extend laterally in the cheek portion of the mask body over a wearer's cheek.

15. A filtering face mask comprising a support frame and a sheet of filtering material defining a mask body adapted to provide a cavity around the mouth and nose of a wearer in use, the filtering face mask comprising a sealing member depending from at least a portion of a peripheral portion of the mask body, the sealing member comprising an inwardly depending lip portion and an outwardly depending lip portion relative to the peripheral portion of the mask body.

16. The filtering face mask of claim 15, wherein the following portions of the peripheral portion of the support frame can include chin portions: the inwardly depending lip portion and the outwardly depending lip portion extend around the portion of the peripheral edge portion of the support frame.

17. The filtering face mask of claim 16, wherein the outwardly depending lip structure has a contact surface that is concave in shape.

18. The filtering face mask of any one of claims 15 to 17, wherein the outwardly depending lip portion is shaped to provide a plateau or rest structure below the wearer's mandible.

19. The filtering face mask of any one of claims 15 to 18, wherein a proximal portion of the outwardly depending lip portion engages the chin of the wearer and a distal portion of the outwardly depending lip portion curves and extends below the chin of the wearer.

20. The filtering face mask of any one of claims 15 to 19, wherein the outwardly depending lip structure is shaped in the form of a chin cup.

21. The filtering face mask of any one of claims 15 to 19, wherein the peripheral edge of the support frame in the vicinity of the inner and outer lip portions is shaped at a first radius from a central point or region of the mask, and the inwardly depending lip portion has an inner edge having a radius less than the first radius.

22. The filtering face mask of any one of claims 15 to 21, wherein the peripheral edge of the support frame in the vicinity of the inner and outer lip portions is shaped at a first radius from a central point or region of the mask, and the outwardly depending lip portion has an outer edge having a radius greater than the first radius.

23. The filtering face mask of any one of claims 15 to 22, wherein the nose portion of the sealing member includes an inwardly depending lip portion having a convex surface for contacting the wearer's face.

24. The filtering face mask of any one of claims 15 to 23, wherein the nose portion of the sealing member includes stiffening structures on each side of the nose.

25. A filtering face mask according to any one of claims 15 to 24, wherein the sealing member is further capable of extending laterally over the cheeks of the wearer, and therefore the filtering face mask is further capable of extending laterally over the cheeks of the wearer.

26. A mask comprising a sealing member depending from at least a portion of a peripheral portion of a mask body, the sealing member comprising a chin region, a nose region, and a cheek region intermediate the chin region and the nose region, and the sealing member further comprising both an inwardly depending lip portion and an outwardly depending lip portion relative to the peripheral portion of the mask body, wherein the inwardly depending lip portion extends around the chin region and the nose region of the sealing member, and the outwardly depending lip portion extends around the chin region and the cheek region of the sealing member.

27. The mask of claim 26, wherein the outwardly depending lip structure in the chin area has a contact surface that is concave in shape.

28. The mask of claim 27, wherein the outwardly depending lip portion in the chin region is shaped to provide a plateau or shelf structure below the wearer's mandible.

29. A mask according to claims 26-28, wherein the cheek regions extend laterally over the cheeks of the wearer.

30. The mask of claim 29, wherein the cheek portion is configured to extend laterally over the cheek of the wearer between an upper edge of a cheekbone of the wearer and a lower edge of a mandible.

31. The mask of any one of claims 29-30, wherein a distance between a first side edge of the mask body and an opposite side edge of the mask body measured along a surface of the mask body can be between 1.2 and 2 times a distance between a top edge of the mask body in the nose region and a bottom edge of the mask body in the chin region measured along the surface of the mask body.

32. A mask according to any one of claims 29-31, wherein the cheek portions each have a first edge that extends from a left or right side edge of the nose portion and is received on a cheekbone of the wearer and a second edge that extends from a left or right side edge of the mouth portion such that the second edge of the cheek portion is received on a lower edge of a jawbone of the wearer, wherein an angle between a tangent to the first edge and a tangent to the second edge of each cheek portion decreases with increasing lateral position.

33. The mask of claim 32, wherein the cheek portions each further comprise a side edge that extends between a distal end of the first edge and a distal end of the second edge.

34. The mask of claim 33, wherein the side edges comprise substantially linear edges.

35. The mask of claim 33 or 34, wherein an angle between the side edge and the first edge is between 70 degrees and 110 degrees; alternatively, the angle between the side edge and the first edge is between 80 degrees and 100 degrees; alternatively, the angle between the side edge and the first edge is about 90 degrees.

36. A mask according to any one of claims 32-35, wherein the first edge is concave in shape.

37. A mask comprising a support frame and a sealing member, the support frame defining a mask body adapted to provide a cavity around the mouth and nose of a wearer in use, and the sealing member depending from at least a portion of a peripheral portion of the mask body, and the sealing member comprising a nose portion which forms a seal against or adjacent the nose of a wearer in use, the nose portion comprising at least one stiffening member.

38. The mask of claim 37, wherein the at least one stiffening member comprises one or more ribs, corrugations, or scallops positioned on each side of a nose region of the sealing member.

39. A mask according to claim 38, wherein the at least one stiffening member comprises one or more corrugations or scallops, wherein a sidewall of the sealing member is shaped to form the one or more corrugations or scallops, and wherein a portion of the sidewall shaped to form the one or more corrugations or scallops has a uniform thickness.

40. A mask according to claim 37 or claim 38, wherein the at least one stiffening member is located on an inner wall of the sealing member.

41. A mask according to any one of claims 37-40, further comprising a sheet of filter material.

42. A mask according to any one of claims 1 to 14 or 26 to 41 or a filtering mask according to any one of claims 15 to 25, the mask or filtering mask further comprising a port, wherein the port is an inlet for breathing gas or inhalation gas.

43. A mask according to any one of claims 1 to 14 or 26 to 41 or a filtering mask according to any one of claims 15 to 25, the mask or filtering mask further comprising an additive comprising silver ions.