WO2022185142A1

WO2022185142A1 - Respirator mask

Info

Publication number: WO2022185142A1
Application number: PCT/IB2022/051500
Authority: WO
Inventors: Claude RIESER
Original assignee: Flawa Consumer Gmbh
Priority date: 2021-03-01
Filing date: 2022-02-20
Publication date: 2022-09-09

Abstract

A respirator mask (1) for protection of the mouth and nose region of a user from dusts and aerosols comprises a filter part (7, 2) that consists of a flat, flexible filter medium (70, 24), which in turn is mechanically reinforced by a flat stiffening structure (71, 22). The stiffened filter part is flexible and/or can be reversibly deformed by application of mechanical force.

Description

RESPIRATOR

field of technology

The invention relates to respiratory protection masks and methods for producing such respiratory protection masks.

Technological background

The terms respirator, protective mask, mask and protective face mask are used synonymously in this description. Respirators are devices that either cover a person's entire face (full face masks) or the wearer's mouth and nose area excluding the eye area (half face masks). Respiratory masks serve to protect the wearer from inhaling potentially harmful substances, in particular toxic or infectious dusts and aerosols. The air is passed through a suitable filter before it is inhaled, in which the unwanted substances are retained. Furthermore, protective masks can additionally or alternatively also be designed to conversely protect the environment from excretions from the wearer. An example of this is medical face masks. Respirator masks are usually fixed to the wearer's head with straps. Protective masks for solid and liquid substances are divided into different classes, depending on the protective effect they have and the filter performance they have. Medical hygiene protective masks are divided into classes I, II and IIR according to the European standard EN 14683 and serve as simple hygiene protection for everyday medical and private use. Hygiene masks primarily protect against liquid drops and coarse dust. Such masks are made from a textile web with three layers of nonwoven fabric, which is gathered in folds and ultrasonically welded at the edges of the mask before the masks are then cut out. Such masks only seal insufficiently at the edges because of the simple and unstable structure. The tighter sealing particle-filtering half masks or fine dust masks are divided into classes FFP1, FFP2 and FFP3 according to the European standard EN 149. Such masks are made from a textile web with several layers of non-woven fabrics. The web is folded, the necessary connections are made by ultrasonic welding and the individual masks are then cut out of the web. This results in a spherical curvature which, if dimensioned appropriately, can close off a user's mouth and nose area well.

WO 96/28217 A1 shows a half-mask that can be folded flat and has a front part and an upper part or lower part which is sealingly connected to the front part above or below it and seals the mask against the face in the nose area or chin area. The three parts consist of a flexible textile filter medium and form a three-dimensional mask body when unfolded.

US 2008/0271739 A1 shows a similar three-part half mask with a front part, an upper part and a lower part. The filter medium of the three parts consists of several textile layers, namely an inner cover layer, an outer cover layer and a filter layer arranged in between. In the front part, between the two cover layers, there is also a stiffening structure in the form of an additional fabric layer, which mechanically reinforces the flexible material in the front part in order to prevent the mask from collapsing when inhaling due to the resulting negative pressure. The top and bottom remain relatively compliant to seal against the user's face. The additional layer in the front part increases the flow resistance, which can lead to more air flowing through the upper part when exhaling. In the case of spectacle wearers, this leads to fogging of the spectacle lenses due to the humid breathing air, especially in cold temperatures.

In FIGS. 1 and 2, WO 2008/085546 A2 shows a two-part half mask that can be folded flat and has two side parts made of a filter medium.

US 2013/0291876 A1 shows a half mask with a one-piece mask body. A rigid mesh is attached to a three-layer filter fleece and formed into a rigid three-dimensional mask body. Rigid three-dimensional skirt will not collapse upon inhalation. However, they are not adaptable to different face shapes. In addition, respirators with a permanently three-dimensional mask body require more volume when stored. With conventional respirators, the wearer's mouth area is not visible. This is problematic when, in support of or as a substitute for acoustic communication, a conversation partner relies on visually recognizing what is being said through the speaker's lip movements (lip reading), or on reading facial expressions as an integral part of sign language. In order to solve this problem, half masks were created in which a viewing window is built into the front part in the area of the mouth.

CN 212088294 U shows a breathing protection mask with a front part and an upper part or lower part which is sealingly connected to this above or below the front part and which seals the mask against the face in the nose area or chin area. The front part consists of a central section made of a transparent film through which the wearer's mouth is visible, and two adjacent sections made of filter material. This multi-part structure of the front part makes the manufacture of such respirators more complex. KR 20200144518 A shows a respirator mask in which a central recess is formed in the filter material of the front part, in which a piece of transparent film is placed as a viewing window. The film viewing window must be placed individually and piece by piece on the front part before it is connected to the filter material along the perimeter. Production accordingly requires additional work steps that are technically complex and error-prone.

A medical hygiene mask made of a transparent, semipermeable membrane is known from WO 2018/140841 A1.

A transparent filter material for protective masks was developed by EPF Lausanne and EM PA St. Gallen ("Project HelloMask"), for which a patent application was filed in March 2020. The fleece fibers are produced by means of electrospinning, resulting in a significantly smaller fiber thickness than with the conventional meltblow process. The transparent filter material shows high flexibility and low rigidity. For the production of medical face masks from this filter medium, it would be necessary to fold the flat structure in a gathered manner, which, however, can have a negative effect on the transparency of the material and the mechanical strength. At the same time, the low rigidity makes the transparent fleece material unsuitable for more complex mask structures such as the three-part mask body from WO 96/28217 A1 and US 2008/0271739 A1.

There is a general need for improvement in this area. Presentation of the invention

An object of the invention is to provide a respirator which does not have at least one of the disadvantages mentioned above and others. In particular, such a respirator should be simple, efficient and inexpensive to produce.

A respiratory protection mask according to the invention should have a low breathing resistance, in particular when inhaling. A respirator according to the invention should not collapse when inhaled. It should be safe and easy to use.

Another object of the invention is to provide an advantageous method of manufacturing respirator masks.

These and other objects are achieved by a respiratory protection mask according to the invention and a manufacturing method according to the invention, according to the independent claims. Further preferred embodiments are given in the dependent claims. A first aspect of the invention relates to an advantageous breathing mask for protecting the mouth and nose area of a user from dust and aerosols. Such a protective mask comprises a filter part consisting of a flat, flexible filter medium which is mechanically reinforced by a flat stiffening structure. The stiffened filter part is flexible and/or can be reversibly deformed by mechanical force.

The purpose of the filter medium is to retain fine dust and aerosols in the air as it flows through the filter medium. Suitable filter media are advantageously equipped as flexible textile fabrics. In order to achieve the desired properties, filter media can be made up of several layers of different materials. For example, a fine-pored filter layer can be arranged between two non-woven cover layers. A possible advantageous structure of a filter medium for a respiratory mask according to the invention can, for example, comprise a first and a second cover fleece made of polypropylene (PP) spunbonded fleece (thermally bonded, 25 g/m2 according to DIN EN 29073 T1 A4, manufacturer: Technitex Sachsen GmbH, DE, type : 00617.02), as well as a porous filter layer made of polypropylene meltblown fleece (25 g/m2, thickness 0.35 or 0.3 mm, manufacturer: Shandong Dawn Polymer Co. Ltd., CN; type: Nantong/Autefa MB25; or alternatively) arranged in between Sandler AG, DE; Type: Sawascreen 8605). Instead of opaque fleece material, the transparent filter medium discussed above can also be used as the filter medium, for which EPF Lausanne and EMPA St. Gallen applied for a patent in March 2020. The disclosure content of this patent application is hereby incorporated in its entirety by reference into this description. Said flexible, transparent filter material can be mechanically stabilized by the stiffening structure in such a way that a mask can be made from it that does not collapse when inhaled.

The stiffened filter part prevents the mask from collapsing when inhaling due to the negative pressure that occurs inside the mask. The stiffening structure determines the mechanical properties of the filter part. If the stiffening structure is designed to be elastically flexible, for example in the form of an elastically flexible, semi-rigid film, then the filter part with the flexible filter medium connected to the stiffening structure is also elastically flexible and semi-rigid. If, on the other hand, the stiffening structure is designed to be permanently deformable by mechanical force, for example in the form of a deformable wire mesh, then the filter part with the flexible filter medium connected to the stiffening structure is also permanently deformable by mechanical force.

The stiffening structure advantageously rests on a surface of the filter medium of the filter part and is permanently connected to it. This external arrangement of the stiffening structure enables a simple construction of the flat filter medium and a simple production of such a mask.

The flat stiffening structure of the filter part can be arranged on a side of the filter part facing away from the face or on a side of the filter part facing the face. The arrangement of the stiffening structure within the filter medium is also conceivable, for example the stiffening structure can be arranged between the outer layers of the filter medium in the case of a multi-layer filter medium. Such a configuration has the advantage that the stiffening structure can also be fixed in a form-fitting manner within the filter medium. The planar stiffening structure of the filter part of a respirator according to the invention is advantageously designed as a grid or as a film which rests on a surface of the filter medium of the filter part and is connected to the filter medium. In a breathing protection mask according to the invention, the area of the stiffening structure of the filter part which overlaps the active area of the filter medium of the filter part is smaller than the area of the active area of the filter medium of the filter part.

The planar stiffening structure of the filter part of a breathing protection mask according to the invention is advantageously designed as a film which has one or more recesses.

This allows the foil to be configured as a frame with a framework structure arranged therein, so that the necessary overall rigidity of the filter part is achieved with a minimum of foil area in the region of the active filter area of the filter part.

The planar stiffening structure of the filter part of a breathing protection mask according to the invention is also advantageously designed as a transparent film.

The surface of the filter medium remains visible, in particular printed written data or graphic decorative elements. If the filter medium itself is transparent, the transparency is not impaired by the film, which is also transparent.

If a transparent film is used, it is advantageously equipped with a suitable anti-reflection layer. Corresponding coatings are known, for example, from the field of plastic spectacle lenses.

Alternatively or additionally, when using a transparent film, this is advantageously coated in such a way that the film does not fog up in humid air, because fogging of the film, i.e. condensation of a large number of very fine water droplets from the humidity on the film, makes the film opaque .

To prevent fogging, the surface of the film is hydrophilic, so that the condensation of water on the surface of the film leads to a closed, invisible film of water instead of droplets. Various technical solutions are known for this. It is known, for example, for polymer films to incorporate monomers with hydrophilic groups, for example with short PEG chains, into the polymer structure. Anti-fog polymeric films are used in particular for packaging fresh vegetables and meat in trays. In a breathing mask according to the invention, the flat stiffening structure of the filter part is advantageously connected to the filter medium of the filter part along a line on the upper and/or lower outer edge and/or a lateral outer edge of the filter part.

The stiffening structure and filter medium can be connected by sewing, stapling, gluing or welding. The connecting line can be designed, for example, as a continuous welding line, as a welding point area or as a sequence of shorter welding lines. The connection is advantageously made by ultrasonic welding.

Fastening means can be provided on the filter part of a breathing mask according to the invention for fastening the breathing mask to a user's head or to protective equipment.

For example, ear straps in the form of elastic cord loops, which are each attached to a lateral end of the front part and are hung behind the user's ears during use, are customary in order to fasten the mask to the user's head. Also common are head straps, in which two elastic straps are placed between the two lateral ends of the mask. In use, these straps then pass around the head of the mask wearer. This variant is particularly suitable for wearers of protective suits that cover the ears. Loose, non-elastic straps that are reversibly knotted behind the button are also possible.

Depending on the material, the straps can be attached to the mask body by tacking or ultrasonic welding.

For example, elastic braided cords can be used for the straps (e.g.: 1: 96% polyester, 4% elastane, diameter 3 mm round; manufacturer: JHCO Elastic; type: 12045; e.g. 2: 40% polyester, 60% elastodiene, diameter 5 mm flat; extensibility 280%; manufacturer: JHCO Elastic; type: 10800). Due to the high extensibility, such straps are particularly well suited for head-spanning straps. Due to the material, the aforementioned straps cannot be ultrasonically welded and are instead stapled to the front part. For example, a hollow cord 2.5 mm x 1 mm made of 77.2% polyamide and 22.8% elastane is well suited for ear straps, which can be bonded to the front part by ultrasonic welding (extensibility 120%; manufacturer: Baumeister; type: A708294). The head straps (head attachment) undergo plastic deformation when the mask is used. In a breathing protection mask according to the invention, a clamping bracket that can be deformed by the action of mechanical force can also be provided on the filter part in the region of the upper outer edge.

Such a clamping bracket allows the flexible material of the upper part to be adapted to the irregular surface of the face in the area of the nose and eyes, which is individual for each mask wearer, and thus to optimize the sealing effect.

Such a clamping bracket can be equipped, for example, as a wire, as a double wire, as a sheet metal strip or as a wire mesh. The clamping bracket can be fastened to the outer surface of the upper part or arranged between the cover layers of the filter medium.

In a breathing protection mask according to the invention, a face-side sealing pad can also be arranged on the filter part in the area of the upper outer edge.

Such a sealing pad, in particular in conjunction with a clamping bracket in the nose area, serves to increase the sealing effect of the breathing mask in the area of the nose and eyes in order to minimize the air flow between the outer edge of the upper part and the skin when exhaling. Among other things, this is intended to prevent fogging of the lenses of spectacle wearers. Foam rubber, for example, or another elastic foam material can be used as a sealing pad. An example of a suitable material is PE foam (thickness 1-2 mm, supplied from a roll and self-adhesive on one side; type: Top-Cell; manufacturer: Topplast).

A particularly advantageous embodiment of a respiratory protection mask according to the invention for protecting the mouth and nose area of a user from dust and aerosols comprises a front part consisting of a flat, flexible filter medium which is mechanically reinforced by a flat stiffening structure; an upper part connected to the front part on a first side of the front part along a first connecting line; and a lower part which is connected to the front part along a second connecting line on a second side of the front part remote from the first side. The front part, the upper part and the lower part together form a concave mask body when the breathing mask is in an open state. The planar stiffening structure of the front part is designed as a film which rests on an outer surface of the filter medium of the front part and is connected to the filter medium. The area of the stiffening structure which overlaps with the area of the filter medium of the front part that is active as a filter is smaller than the area of the area of the filter medium of the front part that is active as a filter. The stiffened front part prevents the mask body from collapsing when inhaling due to the resulting negative pressure inside the mask, while the flexible lower and upper part allows the mask body to fit flush and tightly against the user's face. The stiffening takes place via the foil, which rests on the outer surface of the filter medium of the front part and is mechanically connected to it. This external arrangement of the stiffening structure enables a significantly simpler construction of the flat filter medium, which can be configured identically in the area of the upper part, the front part and the lower part, and also simpler production of such a mask.

The surface of the filter medium of the front part that is active as a filter is that surface of the filter medium through which air can potentially flow back and forth between the half-space of the mask on the face side (i.e. the inside of the mask) and the half-space of the mask facing away from the face (i.e. the outside of the mask). Since the area of the stiffening sheet which overlaps this active filter area of the front part is smaller than this active filter area, part of the active filter area of the front part remains open and the air flow is not blocked by the stiffening sheet. Overall, the flow resistance of the front part is the same or less than with a continuous stiffening layer inside the filter medium, as is known from the prior art.

The front part can be connected to the upper part along the first connecting line, or the front part can be connected to the lower part along the second connecting line, for example by sewing, stapling, gluing or welding. The connection is advantageously made by ultrasonic welding, which, however, requires suitable thermoplastic materials for this purpose.

A polymer film is advantageously used for the film of the stiffening structure, for example a film made from unstretched polypropylene (CPP) with a thickness of 0.13 mm. The film is particularly advantageously transparent

The film can be provided with an anti-fog coating and/or an anti-reflection coating.

Polypropylene (PP) films or polyethylene terephthalate (PET) films, for example, can also be used. However, other flat, flexible structures such as cardboard or thin sheet metal are also suitable as stiffening structures. However, thermoplastic polymer films have the advantage, among other things, that they can be firmly bonded to the filter medium by ultrasonic welding. Instead of opaque non-woven material, the transparent filter medium discussed above can also be used as the filter medium, for which EPF Lausanne and EM PA St. Gallen applied for a patent in March 2020.

Said flexible, transparent filter material can be mechanically stabilized by an advantageously transparent stiffening film, as discussed above, in such a way that a mask of the three-part type described can be produced from it.

The film of the stiffening structure of the front part of the respirator mask can be arranged on the side of the front part facing away from the face, ie the outside of the mask, or on the side of the front part facing the face, ie the inside of the mask.

In an advantageous embodiment of a respirator mask, the foil of the stiffening structure of the front part has one or more recesses.

This allows the foil to be designed as a frame with a framework structure arranged therein, so that the necessary overall rigidity of the front part is achieved with a minimum of foil area in the region of the active filter area of the front part.

The foil of the stiffening structure of the front part is advantageously transparent.

On the one hand, the surface of the filter medium remains visible, in particular printed written data or graphic decorative elements. If the filter medium itself is transparent, the transparency is not impeded by the film, which is also transparent.

On the other hand, the film can also act as a viewing window, which will be discussed below.

In a particularly advantageous embodiment of a respirator mask, the filter medium of the front part has a recess which is completely covered with the foil of the stiffening structure of the front part. Said film closes said recess in a sealing manner. Said film is transparent.

In this way, the transparent film together with the recess in the filter medium forms a viewing window in the front part of the breathing mask. If the recess is placed in such a way that the recess lies over the mouth of the mask wearer when the mask is used as intended, then a third person can see the mouth image of the mask wearer. In this way, people with hearing impairments can communicate using lip reading or sign language despite wearing a protective mask. In connection with respiratory protection masks according to the invention, a tight connection does not necessarily mean a fluid-tight connection. In connection with respirator masks, any connection can be described as tight if the flow resistance is several orders of magnitude higher than the flow resistance of the filter medium, so that for this reason alone there is no gas flow through this connection. For example, by means of a large number of focal points or lines, two filter media or a film and a filter medium can be sealingly connected, although there is no closed welding line. In the area between the welding points, however, the two layers are so close together that the flow resistance between the two layers is much higher than the flow resistance of the filter medium perpendicular to the filter surface.

Advantageously, in such an embodiment of a breathing mask, the film of the stiffening structure of the front part is sealingly connected to the filter medium along the circumference of the recess of the filter medium of the front part. The film of the stiffening structure of the front part is also advantageously coated in such a way that the film does not fog up in moist air. A fogging of the film, ie a condensation of a large number of very fine water droplets from the humidity, especially in the breathing air, is unfavorable in view of the additional effect of the film as a viewing window and should therefore be avoided to advantage. The same applies when using a transparent filter medium.

As an alternative or in addition, the film can also be equipped with a suitable anti-reflection layer in a breathing mask according to the invention. Corresponding coatings are known, for example, from the area of plastic spectacle lenses. Avoiding reflections on a transparent foil improves the view from the outside through the viewing window of the mouth area, since the reflection of light on the foil is avoided. This can be the case in particular with direct sunlight or point-shaped light sources.

The foil of the stiffening structure of the front part is advantageously connected to the filter medium along a line on the upper and/or lower outer edge of the front part.

The foil and filter medium can be connected by sewing, stapling, gluing or welding. The connecting line can, for example, be a continuous welding line, a welding spot area or a series of shorter ones Weld lines be configured. The connection is advantageously made by ultrasonic welding.

The connecting line particularly advantageously coincides with the corresponding connecting line between the front part and the upper part or the lower part.

Fastening means are advantageously provided for attaching the respirator to the head of a user or to a protective equipment with a respirator on the front part. Suitable fasteners have already been discussed above.

In an advantageous embodiment variant of a respirator mask, a clamping bracket is arranged on the upper part in the area of the outer edge, which can be deformed by mechanical force. Suitable clamping brackets have already been discussed above.

In a further advantageous embodiment variant of a respirator mask, a sealing pad is attached to the upper part in the area of the outer edge on the side facing the face. Suitable sealing pads have already been discussed above

A second aspect of the invention relates to a method for manufacturing a folded breathing mask, comprising the steps:

providing a web of sheet-like filter media;

Creating the edge contours of an upper part and a lower part of a respirator mask, for example by ultrasonic welding;

- Separating the material lying outside the edge contours along the created edge contours of the upper part and the lower part;

- Placing a film web on the filter medium web in the area of a front part of the respirator;

folding the web of filter media so that the portions of the top, bottom, and face are superimposed;

Creating a sealing connection between the front part and the upper part and between the front part and the lower part, for example by ultrasonic welding;

- Separating the material lying outside the outer contours of the front part along the outer contours of the front part;

Providing the isolated, folded mask body for further processing. The foil web can be placed on the filter medium web before or after the filter medium is folded.

Recesses in the foil are advantageously cut out of the foil before the foil is placed on the filter medium. If necessary, outer contours can also be cut into the film.

In an advantageous variant of such a method, after the foil web has been placed on the filter medium web, the foil is welded to the filter medium.

In a further advantageous variant of such a method, a recess is cut out in the web area of the front part before the foil web is placed on the filter medium web.

If the mask to be produced is provided with a clamping element, this can be placed on the finished filter medium or on one of the layers of the filter medium before the various layers are brought together. Advantageously, the clamping element is supplied from a roll, cut to length and made available in this way. A sealing pad is advantageously supplied from a roll, cut out to fit and placed at the appropriate point on the future upper part before the filter medium is folded.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, reference is made to the drawings below. These only show exemplary embodiments of the subject matter of the invention. In the figures and the associated description, parts that are the same or have the same effect are provided with the same or at least similar reference symbols. FIG. 1 schematically shows an advantageous protective mask in a front view.

FIG. 2 schematically shows another advantageous protective mask in a front view.

FIG. 3 schematically shows a further advantageous protective mask in a front view. FIG. 4 schematically shows another advantageous protective mask in a front view.

FIG. 5 shows in perspective an advantageous protective mask fastened to a user's head. FIG. 6 shows the protective mask from FIG. 5 in a perspective side view.

FIG. 7 shows, separately and schematically, the individual parts of the protective mask from FIG. 5, with (a) the upper part, (b) the front part, and (c) the lower part of the protective mask.

FIG. 8 shows a perspective view of the protective mask from FIG. 5 in the folded state from the rear.

FIG. 9 schematically shows the front part of a further embodiment of an advantageous protective mask without a viewing window, in the folded state with a view of the front part.

FIG. 10 schematically shows three further embodiments of advantageous protective masks without a viewing window, in the open state, worn by a user.

FIG. 11 schematically shows the individual work steps of an advantageous method for producing an advantageous protective mask. Ways to carry out the invention

The examples given below are given to better illustrate the present invention, but are not intended to limit the invention to the features disclosed herein.

Various exemplary embodiments of a respirator mask 1 according to the invention with a one-piece filter part 7 are shown schematically in FIGS. 1, 2, 3 and 4, with a view of the front side facing away from the face.

The respirator mask 1 shown in FIG. 1 comprises a one-piece filter part 7 and two lateral fastening means 5 fastened to it in the form of elastic ear loops. The filter part 7 consists of an essentially rectangular, flat filter medium 70 and a flat stiffening structure 71 fastened to the filter medium 70.

The flat filter medium 70 can be constructed, for example, as a three-layer filter, with an outer cover fleece, an inner cover fleece and a filter fleece lying in between. Alternatively, the flat filter medium can also be designed as a transparent filter medium. A protective mask 1 with a transparent filter medium allows the mouth area of the mask wearer to be seen from the outside, so that the facial expressions and in particular the mouth image remain visible.

The planar stiffening structure 71 is designed as a lattice network 72 with a plurality of thin rods lying at right angles to one another. The area of the filter medium 70 covered by the grid 72 is comparatively small, so that the flow resistance of the filter medium is not adversely affected. At the same time, with a transparent filter medium, the view through the filter medium is essentially unhindered. The grid 72 can be designed, for example, as a one-piece grid structure made of polymer, or can be made by joining horizontal and vertical rods together. If the filter part is to have elastic, semi-rigid properties as a whole, a grid made of an elastic plastic material is particularly suitable as a stiffening means. If, on the other hand, the filter part is to be deformable or formable as a whole, a grid in the form of a deformable metal wire grid is particularly well suited.

The grid can be connected to the filter medium, for example, by gluing, or by welding, in particular ultrasonic welding. Compatible materials are advantageously used in ultrasonic welding, particularly advantageously essentially identical thermoplastic polymers. With a wire mesh, the wire may be coated with polymer.

Instead of connecting the entire grid to the filter medium, it can also be attached only along the outer edges. In such a case, however, the filter medium can lift off from the stiffening structure in the case of negative pressure. Such an embodiment variant is therefore particularly useful when the stiffening structure is connected to the face-side surface of the filter medium. This prevents the filter medium from collapsing when inhaled, since it is supported by the stiffening structure despite the lack of a connection. The planar stiffening structure 71 in the form of the wire mesh 72 can also be connected to the filter medium 70 at a plurality of connection points 711 . Such connection points can be designed in particular as ultrasonic welding points or adhesive points. Such an embodiment of a protective mask 1 according to the invention is shown, for example, in FIG. 2, in two variants. Elements that are the same as in FIG. 1 are not dealt with separately.

On one side to the right of the dashed auxiliary line, the grid 72 is connected to the filter medium with connection points 711 (black points) at all node points of the grid. As an alternative to this, connection points 711 can also only be provided at every second node of the grid, as shown on the page to the left of the dashed auxiliary line.

The specific arrangement of the connection points in this figure 2 is primarily intended to illustrate the principle. As a rule, however, the arrangement of the connection points is chosen to be essentially symmetrical. However, it is possible that more or fewer connection points are used in different zones of the filter part. This allows the mechanical properties of the filter part to be designed differently in the zones. For example, only every second node of the grid can be connected to the filter medium in a central zone of the rectangular filter medium, and every node in an outer region. A further variant of a respirator mask 1 according to the invention is shown in FIG. In this exemplary embodiment, the flat stiffening medium 71 is designed as a foil 73, which is essentially congruent with the filter medium 70 underneath. The foil 73 has a plurality of hexagonal recesses 731, so that the remaining material of the foil 73 has a framework structure of webs 732 forms.

The foil 70 preferably consists of the same polymer material as the filter medium 70. If the filter medium is made of polypropylene fleece, for example, the foil is preferably also made of polypropylene. On the one hand, this allows the various components to be easily connected by ultrasonic welding. On the other hand, the uniform material makes it easier to recycle the protective masks.

The flat stiffening medium 71 designed as a film 73 is advantageously connected to the filter medium 70 along the circumference, for example by ultrasonic welding. In addition, the film 73 can be selectively connected to the filter medium 70 at the webs 732 and/or the nodal points of the webs, for example by ultrasonic welding. The corresponding connection points are not shown in the figure.

The connection points can be arranged according to the desired mechanical properties of the filter part. For example, the number and arrangement of the connection points can be selected so that, on the one hand, the desired mechanical stabilization of the filter medium is achieved and, on the other hand, when inhaling, the filter medium can lift itself off a stiffening structure arranged away from the face so far due to the negative pressure that the filter surface can also be damaged is exposed under part of the foil. In this way, the inhalation resistance of the protective mask can be minimized. For example, in the area of the webs 732, every second node at which three webs meet can be connected to the filter medium.

If a transparent filter medium is used, the foil is also advantageously transparent so that the view through the transparent filter medium is not restricted. The shape and distribution of the recesses in the foil can be chosen in such a way that the desired mechanical properties of the stiffening structure are achieved. Corresponding variants will be discussed further below, for example in FIGS. 9 and 10.

Another embodiment of a protective mask 1 according to the invention is shown in FIG. A flat stiffening structure 71 in the form of a grid 72 analogous to FIGS. 1 and 2 is arranged within a filter medium made of two or more layers.

The filter medium 70 can consist, for example, of an outer cover fleece, an inner cover fleece and a filter fleece lying in between. Alternatively, the flat filter medium can also consist of two layers of a transparent filter medium, for example. The layers of the multi-layer filter medium are preferably connected to one another along the circumference, for example by ultrasonic welding. The grid 72 arranged between two layers of the multi-layer filter medium 70 is thus fixed in the filter part 7 in a form-fitting manner. In order to achieve the mechanical stabilization of the filter medium 70 by the stiffening structure 71 in the inner area, the individual layers of the multi-layer filter medium 70 are connected to one another at a plurality of connection points 701 perpendicularly to the filter plane. This can easily be achieved, for example, by means of an ultrasonic spot weld. One results additional positive fixation of the grid 72 in the inner area of the filter part, and thereby indirectly a mechanical stabilization of the filter medium.

The connection points 701 (black points) are arranged in all gaps of the grid on one side to the right of the dashed auxiliary line. As an alternative to this, connection points 701 can also only be provided in every second gap in the grid, as shown on the page to the left of the dashed auxiliary line. The arrangement of the connection points in this Figure 4 is again intended for illustration. The arrangement of the connection points is advantageously chosen to be essentially symmetrical. It is possible that more or fewer connection points are used in different zones of the filter part. This allows the mechanical properties of the filter part to be made different in the zones. For example, a connection point can be provided in a central zone of the rectangular filter medium only in every second gap of the grid, and in an outer area in every gap of the grid.

Instead of the grid 72, a foil-shaped stiffening structure can also be used in such an embodiment, for example the foil 93 from FIG.

Since no direct connection of the stiffening structure to the filter medium is necessary, the corresponding materials do not have to be compatible.

The form-fitting fixing of the stiffening structure within the filter medium also makes it possible to use a plurality of linear rods that are not connected to one another instead of a lattice network. For example, elastically flexible polymer filaments of a certain thickness can be provided from a roll, cut to length and placed on a first partial layer of the filter medium. The second partial layer of the filter medium is then placed on the first partial layer and the stiffening structure, and the layers of the filter medium are connected to one another along the circumference and at the connection points provided.

Such manufacture can reduce manufacturing costs because the manufacturing step for the lattice structure is eliminated. Furthermore, it is also possible to select different distances between the individual rods in order to also influence the mechanical properties of the filter part. Likewise, different materials can be used, for example, for the horizontal and vertical bars of the stiffening structure. For example, it is possible to fabricate the horizontal bars 721 from an elastic polymer filament and the vertical bars 722 from a malleable metal wire. All of the exemplary embodiments of protective masks according to the invention discussed above can be provided with a clamping element, for example a double-wire clip, which is fastened to an upper edge of the filter part. Such a clamping element serves to adapt the upper edge of the filter part to the shape of the nose area and thus to improve the sealing effect.

The aforementioned exemplary embodiments of protective masks according to the invention have an essentially flat filter part. When the mask is put on, this is deformed in such a way that a three-dimensional mask body is created, which can seal the mouth and nose of the wearer. As an alternative, the above-mentioned design variants can also be implemented analogously to the known medical hygiene masks with a filter part gathered at the side. For this purpose, the finished filter part made of filter medium and stiffening structure is gathered at the lateral edges so that several horizontal folds are formed. As a result, the side edges are shortened, with the horizontal folds being unfolded again when the mask is put on in the inner area, and a concave mask body is created. In contrast to the conventional medical hygiene masks, however, such masks according to the invention are stiffer because of the additional stiffening element, so that they collapse less when inhaled, or a thinner filter medium can be used with the same stiffness.

Analogously to the protective masks according to the invention discussed above, more complicated mask geometries can also be produced from the shown advantageous combination of flat filter medium and flat stiffening structure. Thus, protective masks with a two-part or three-part filter part, as known for example from WO 96/28217 A1, US 2008/0271739 A1 or WO 2008/085546 A2, can be manufactured with a filter part according to the invention. In this way, such more complex protective masks can also be realized from a less dimensionally stable transparent filter medium such as the already discussed filter medium from EPFL and EMPA.

In a possible variant, the flat filter medium and the flat connection structure are connected to one another as disclosed above. The resulting flat structure is then processed into the two-part or three-part mask bodies like a conventional filter medium.

Stiff, three-dimensional mask bodies, as shown by way of example in US 2013/0291876 A1, can also be manufactured with a filter part according to the invention For example, to make a protective mask from the less dimensionally stable transparent filter medium from EPFL and EM PA. For this purpose can

In a possible variant, the flat filter medium and the flat connection structure are in turn connected to one another to form a flat structure. This can then be brought into the desired three-dimensional shape, for example by pressing the flat filter structure into a concave shape with a convex die. The filter part forms folds in a controlled manner. The three-dimensional structure of the filter part can then be fixed in that the regions of the filter part folded over one another are connected to one another at the periphery, for example by ultrasonic welding.

In another variant, the flat stiffening structure and the flat filter medium are pressed into the concave shape independently of one another. For example, first the stiffening structure and then the filter medium can be pressed into the mold. The connection between the stiffening structure and the filter medium then only takes place in the three-dimensional structure.

In the aforementioned manufacturing processes, the planar stiffening structure is advantageously designed in such a way that it is not mechanically damaged during forming or pressing into the mold. Even more advantageously, the planar stiffening structure is designed in such a way that after the shaping step in the three-dimensional shape, the elements of the stiffening structure are arranged at the intended location.

A further exemplary embodiment of a respirator mask 1 according to the invention is shown in FIGS. 5, 6, 7 and 8. The mask body of the respirator mask 1 consists of an upper part 3, a front part 2 and a lower part 4. The upper part 3 is sealingly connected to the front part 2 along a connecting line 11. The lower part 4 is in turn connected to the front part 2 in a sealing manner along a connecting line 12 . Because of the curved connecting lines 11, 12, the upper part 3, the front part 2 and the lower part 4 together form a three-dimensional, concave mask body. Together with a suitable shape of the outer edges 35, 45 of the upper and lower part 4, the concave mask body can thus seal off the mouth and nose area of a mask wearer, so that air can essentially only flow from the outside through the filter medium 24, 34, 44 into the mask interior 13 can get (inhalation of the mask wearer) or can only get through the filter medium 24, 34, 44 from the inside of the mask to the outside 14 (exhalation of the mask wearer). The upper part 3 consists of the flat filter medium 34, with an outer cover fleece 341, an inner cover fleece 342 and a filter layer lying in between (not visible). A sealing pad 33 is arranged in the area of the outer edge 35 on a side 13 facing the face. When the mask 1 is worn, this sealing pad 33 rests on the nose and face of the mask wearer. A clamping element 32 is arranged on the side 14 of the upper part of the respirator mask which faces away from the face. The clamping element 32 consists of a deformable wire element, which is deformed to fit the shape of the nose and eye area in order to adapt the upper part 3 precisely. In this way, the facial region can be sealed off as tightly as possible by the upper part.

In a spot welding zone 31 on the outer edge 35 of the upper part 3, the various layers of the filter medium 34 are firmly connected with a large number of ultrasonic welding points throughout the entire thickness of the filter medium.

The lower part 4 consists of the same three-layer filter medium 44 as the upper part 3. In the case of the lower part 4, the various layers of the filter medium 44 are also connected in a spot welding zone 41 on the outer edge 45 of the lower part 4 with a large number of ultrasonic welding points through the entire thickness of the filter medium . The lower part 4 seals off the mask interior in the chin area of the mask wearer against the face.

The front part 2 consists of the same three-layer filter medium 24 as the three-layer filter medium 34, 44 of the upper part 3 or lower part 4. The filter medium 24 has a recess 23 in a central area above the mouth of the mask wearer. A stiffening film 22 is attached to the filter medium 24 on the side 14 of the front part 2 facing away from the face. The stiffening film 22 has three recesses 221 in each of the two lateral areas next to the recess 23 of the filter medium 24 , in which the filter medium 24 is not covered by the film 22 . In the area of the recess 23 of the filter medium 24, however, the film 22 has no recess and covers the entire recess 23. A weld seam 26 runs around the recess 23 and connects the film 22 and the filter medium 24 in a materially bonded manner. The recess 23 is thus closed by the fluidically tight film 22 .

The foil 22 is transparent. As a result, the mouth of the mask wearer is visible from the outside through the viewing window formed from the recess 23 and the overlying film 22 . A third party can thus recognize both the facial expressions and the mouth image of the mask wearer. At an upper edge of the front part 2, the film 22 is materially bonded along a weld seam 25 on the connecting line 11 to the filter medium 24 of the front part 2 and to the filter medium 34 of the upper part 3 by ultrasonic welding. Analogously, the film 22 is materially bonded along a weld seam 27 on the connecting line 12 to the filter medium 24 of the front part 2 and to the filter medium 44 of the lower part 4 by ultrasonic welding.

In the exemplary embodiment shown, the weld seam 27 coincides with the peripheral weld seam 26 in the central area. However, analogous to the upper edge of the front part 2, it would be possible to design the two weld seams 26, 27 separately. The upper part 3, the front part 2 with the filter medium 24 and foil 22 and the lower part 4 are bonded to one another laterally in the spot welding zone 21, 31', 41'. In the area of the spot welding zone 21, fastening means 5 in the form of elastic ear loops are also connected to the front part 2 in a materially bonded manner by ultra-welding. The recesses 221 in the film 22 form webs 222 of the film 22 which rest on the outer non-woven cover fabric 241 of the filter medium 24 . The webs 222 are designed in such a way that the stiffening film 22 in conjunction with the weld seams 25, 26, 27 mechanically reinforces the very flexible filter medium 24 in such a way that when inhaling, despite the negative pressure forming inside the mask 13, the front part does not move too far in the direction of the face is pressed, so the mask does not collapse.

At the same time, the recesses 221 are designed in such a way that a sufficiently large active filter area of the filter medium 24 remains, in which the filter medium is not covered by the foil 22 and air can flow through the filter medium.

The breathing resistance of the filter medium of the front part is not negatively influenced. When inhaling, the filter medium 24 is pushed slightly towards the inside 13 of the mask due to the pressure difference. As a result, the filter media 24 lifts away from the ridges 222 and the surface of the filter media 24 underlying the ridges 222 is also temporarily exposed. When inhaling, the entire surface of the filter medium 24 is therefore available for the air to flow through. This means that the breathing resistance is as low as possible, especially when inhaling.

Depending on the design of the webs 222, it is also possible to connect the film 22 to the underlying filter medium 24 at certain points of the webs in order to optimize the mechanical stability of the entire front part 2. In the figures 5 and 6, the respirator mask 1 shown is shown in the three-dimensional open configuration. The upper part 3 and the lower part 4 can be folded onto the front part 2 along the connecting lines 11, 12 in such a way that the mask body is flat in a closed configuration (cf. FIG. 8). This closed configuration also results directly from the manufacture of the respirators. The corresponding procedure will be discussed further below.

The front part 2 of a respirator mask 1 according to the invention can also be designed without a recess 23 in the filter medium 24 of the front part 2 . The advantageous effect of an external stiffening of the flexible filter medium 24 is also given in such an embodiment. A possible exemplary embodiment of such an advantageous front part 2 of a respirator mask 1 is shown in FIG. A foil-shaped stiffening structure 22 is arranged on the filter medium 24 and is connected to the filter medium 24 by ultrasonic welding along two connecting lines 11 and 12, analogously to the previous exemplary embodiment. The stiffening film 22 has several recesses 221, resulting in a structure of webs and crossing points 222 which, in cooperation with the connecting seams 27 and 25 on the outer edges of the front part 2, bring about the desired stiffening of the front part.

In this exemplary embodiment of a front part 2, the surface covered by the film 22 of the underlying filter medium 24, which is in operative connection with the inside of the mask, is significantly smaller than the surface of the recesses 221 in the film 22. The active filter surface of the front part 2 is thus covered by the film 22 reduced only to a small extent. The increase in flow resistance is the same as or less than it would be if an additional stiffening layer were introduced within the filter medium over the entire active filter surface, as is known from the prior art.

When inhaling, the filter medium 24 of the front part 2 is additionally pressed in the direction of the mask interior due to the negative pressure when inhaling, so that the surface of the filter medium 24 below the film 22 is also exposed and is available for the air to flow through.

It is also possible to connect the foil 22 to the underlying filter medium 24 at one or more additional connection points in order to influence the overall stability of the front part in the desired manner. As an example, a connecting weld seam 28 is shown in Figure 9 along a center line of the front part 2, along which the foil 22 with the underlying filter medium 24 connected is. In this way, the lifting of the filter medium 24 from the foil 22 during inhalation is controlled in such a way that essentially the full area of the active filter medium 24 is available without the filter medium 24 touching the nose or mouth area of the mask wearer. Further exemplary embodiments of advantageous breathing masks 1 are shown in FIG. In a first example in FIG. 10(a), four recesses 221 are arranged in the film 22, resulting in a reduced web structure 222 with five webs and two crossing points. As in the previous exemplary embodiments, two connecting lines 11 and 12 are provided on the upper and lower edges of the front part, along which the film 22 and the filter medium of the front part 2 are connected to one another.

Practically the entire surface of the filter medium 24 is accessible to the air flowing through. The film 22 can optionally be connected to the underlying filter medium 24 along webs or at individual points. For example, a connecting seam (not shown) can be provided along the horizontal web between the two crossing points, along which the film 22 is cohesively connected to the filter medium 24 of the front part 2 by ultrasonic welding. In this way, the possible lifting of the filter medium 24 from the foil structure 22 during inhalation can be determined in a suitable manner. Another example of a respirator according to the invention is shown in Figure 10(b). In addition to a central recess 221 in the film 22, two smaller recesses 221 are provided in the film 22 on the side. The result is two individual webs of the film 22 spanning the filter medium 24, which connect the upper connecting line 11 and the lower connecting line 12 of the film to one another and thus mechanically stabilize the film. Again, the filter medium 24 can optionally be connected to the underlying filter medium 24 along the webs 222 or at individual points of these webs.

Yet another example of a respirator according to the invention is shown in Figure 10(c). In this embodiment, the film 22 has a larger number of recesses 221, resulting in a more complex framework structure of webs and crossing points 222. In such an embodiment, the filter medium 24 is advantageously only connected to the filter medium 24 at individual connection points if it is to be possible for the filter medium to be lifted off the webs 222 . Since the framework structure is very stable due to the large number of webs and crossing points, the width of the webs can be reduced to a minimum. In this way, only a small surface area of the filter medium 24 is blocked by the foil 22, so that lifting of the filter medium 24 would no longer significantly reduce the resistance during inhalation. In such a case, the film 22 can also be connected to the filter medium 24 along all webs or at all crossing points, which would further stabilize the front part.

In addition to the advantageous technical effects of the discussed respirators per se, such respirators can also be manufactured in an efficient manner.

For the production of three-part respirators with a front part, an upper part and a lower part, it is known from the prior art to provide a generally multi-layered filter medium as an endless web, the different layers of the filter medium along the outer edges of the future upper parts and lower parts To connect ultrasonic welding, and to fold the two outer web segments, on which the future tops and bottoms are located, respectively, onto the central web segment lying in between, on which the future front parts are located. The connections between the upper part and the front part or between the lower part and the front part are created by ultrasonic welding along suitable connecting lines. Overhanging material is cut off along the outer edges of the front part and the individual finished masks are separated from the continuous web. Fastening means, such as ear straps or head straps, can then be attached to these individual, completely folded masks.

A method according to the invention for the production of one of the prescribed breathing masks allows the production to be carried out in a continuous manner without additional more complex production steps. In particular, a complex production of the filter medium with inserts to be positioned precisely and the placement of individual components such as viewing windows can be dispensed with.

An example of an advantageous manufacturing method for breathing masks according to the exemplary embodiments discussed above is shown in FIG. In a first step S21, the filter medium is provided as a continuous web, in that a continuous web of the outer cover fleece, the filter fleece and the inner cover fleece are brought together and laid flat on top of one another. The filter medium of the upper part, the lower part and the front part of a respirator mask will later be formed from this web of filter medium. In a next step S22, the three layers of the filter medium are bonded by ultrasonic welding along the outer edges of the future lower part and the future upper part and are thus fixed to one another in an immovable manner for the further manufacturing process. If it is provided that the breathing mask has a clamping element, then in a separate step S11 a wire element can be cut to length off the roll and fixed on the filter medium at the intended location on the future upper part. The clamping element is advantageously designed to be self-adhesive on one side in order to achieve efficient, irreversible fixing. Alternatively, the clamping element can be placed on one of the layers, in particular on an inner layer of the filter medium, before the various fleece layers of the filter medium are brought together.

If the respirator is intended to have a sealing element in the nose area, then in a separate step (not shown) S11, a corresponding sealing pad, for example made of PE foam, can be supplied from a roll, cut out to fit and placed on the filter medium at the intended location on the future top to be fixed. The sealing layer is advantageously designed to be self-adhesive on one side in order to achieve efficient, irreversible fixing.

In a next step S23, protruding edge material of the filter medium web is cut off S23a along the outer edges of the future upper part and lower part of the respirator mask. Advantageously, in the same step S23, the recess for the future viewing window of the front part is cut S23b in the filter medium web, if such a viewing window is provided.

Parallel to this, in a preparatory step S12, an endless web of film is provided and the intended recesses are cut into the film. This film web is then placed on the filter medium web in a step S24. Then, in a further step S25, the film is connected to the filter medium by ultrasonic welding along the circumference of the window recess in the filter medium. The film is now also immovably connected to the filter medium. Depending on the configuration of the front part, additional or alternative connection points can be provided between the film and the filter medium, which can be created in this step S25. Even if, in addition to the connecting seams that are still to be created, there are no further connection points between the film and filter medium in the finished front part, temporary connection points can be created for temporarily fixing the film on the filter medium in that area of the filter medium that will be cut away later.

In a next step S26, the two outer web segments of the filter medium are folded onto a central area in such a way that the front part, the bottom part and the top part of the future breathing mask lie on top of one another in the correct orientation. The film is not folded because it does not overlap with the web areas of the bottom and top. In a next step S27, the films lying on top of one another are then welded along a first connecting line 11, 25 between the front part and the upper part and a second connecting line 12, 27 between the front part and the lower part and in the spot welding zones 21, 31', 4 at the two lateral ends of the mask - Layer and filter medium layer of the front part and the film layer of the upper part or the film layer of the lower part connected to each other by ultrasonic welding.

Fastening straps in the form of ear loops are cut to length from an elastic braided cord in a preparatory step S13, placed on the front of the front part in the area of the welding zone 21 in a step S28 and fastened to the front part in a step S29.

If fastening straps are designed as straps spanning the head, two cords are advantageously fed from a roll parallel to the path of the filter medium and fastened on the front side of the front part in the area of the welding zone 21 on the front part. A separate detachment of the fastening straps from the roll is not necessary here, since the detachment takes place during the detachment S30 of the masks from the continuous web, which is described below.

If the material of the cord used is suitable, this can be done by ultrasonic welding. Otherwise, the straps can also be attached to the front part by stapling or gluing.

In a final step S30, the protruding material of the future mask, both the filter medium and the foil, and possibly the headband, is cut off along the outer contours of the front part and the individual masks are separated from the continuous web. The individual masks that have already been folded can now be processed further, in particular stacked and/or packaged. As long as the mask bodies are still in the continuous web, the relative position of the mask bodies with respect to the processing devices of the production line is clearly defined and can be easily checked, which simplifies the execution of steps S28, S29. Alternatively, steps S28, S29 can also be carried out after the mask bodies have been separated. However, this increases the effort required to carry out the necessary processing steps reliably.

The present invention is not limited in scope to the specific embodiments described herein. Rather, for the person skilled in the art, from the description and the associated figures, in addition to the examples disclosed here, various further modifications of the present invention result, which also fall within the scope of protection of the claims. In addition, various references are cited in the description, the disclosure content of which is hereby incorporated in its entirety by reference into the description.

Reference List

1 respirator

11 first connecting line

12 second connecting line

13 Inside of the mask, side facing the face

14 Outside of the mask, facing away from the face

2 front part

21 spot welding zone

22 flat stiffening structure, foil

221 recess in foil

222 footbridge

23 Window recess in the mouth area

24 flat filter medium

241 Outer surface of the flat filter medium, outer fleece layer

242 inner surface of the flat filter medium, inner fleece layer

25 upper connection weld

26 all-round connection weld seam

27 lower connection weld

28 connection weld

3 top

31 spot welding zone

32 clamps 33 waterproofing pad

34 flat filter medium

341 outer fleece layer

342 inner fleece layer 35 outer edge

4 base

41 spot welding zone

44 flat filter medium 441 outer fleece layer 442 inner fleece layer

45 outer edge

5 fasteners

7 filter part

70 flat filter medium 701 attachment points

701 outer surface of the flat filter medium

702 inner surface of the sheet-like filter medium

71 planar stiffening structure

711 attachment points 72 grids

721 horizontal bar

722 vertical grid bar

73 slide

731 recess 732 bar

Claims

patent claims

1. Respirator mask (1) for protecting the mouth and nose area of a user from dust and aerosols, comprising a filter part (7, 2) consisting of a flat, flexible filter medium (70, 24) which is strengthened by a flat structure (71, 22) is mechanically reinforced; wherein the stiffened filter part is flexible and/or can be reversibly deformed by the action of mechanical force.

2. Respiratory protection mask according to claim 1, wherein the planar stiffening structure (71, 22) of the filter part (7, 2) is arranged on a face-facing side (14) of the filter part or on a face-facing side (13) of the filter part.

3. Respiratory protection mask according to claim 1 or 2, wherein the flat stiffening structure of the filter part (7, 2) is designed as a grid (72) or as a film (73, 22) which is attached to a surface (701, 241, 702, 242) of the Filter medium (70, 24) of the filter part rests and is connected to the filter medium (25, 26, 27, 28).

4. Respiratory protection mask according to one of the preceding claims, wherein the area of the stiffening structure (71, 22) of the filter part (7, 2) which overlaps with the active as a filter area of the filter medium (70, 24) of the filter part is smaller than the surface area of the filter medium of the filter part that is active as a filter.

5. Respiratory protection mask according to one of the preceding claims, wherein the planar stiffening structure of the filter part (7, 2) is designed as a film (73, 22) which has one or more recesses (731, 221).

6. Respiratory protection mask according to one of the preceding claims, wherein the planar stiffening structure of the filter part (7, 2) is designed as a transparent film (73, 22).

7. Respiratory protection mask according to one of the preceding claims, wherein the planar stiffening structure of the filter part (7, 2) along a line (25, 27) on the upper and/or lower outer edge and/or a lateral outer edge of the filter part with the filter medium ( 70, 24) of the filter part.

8. Respiratory mask (1) according to one of the preceding claims for protecting the mouth and nose area of a user from dust and aerosols, comprising a front part (2) consisting of a flat, flexible filter medium (24) which ches by a flat stiffening structure (22) is mechanically reinforced; an upper part (3) which is connected to the front part on a first side of the front part along a first connecting line (11); and a lower part (4) which is connected to the front part along a second connecting line (12) on a second side of the front part remote from the first side; wherein the front part, the upper part and the lower part together form a concave mask body in an open state of the respirator mask; wherein the flat stiffening structure of the front part is designed as a film (22) which rests on an outer surface (241) of the filter medium of the front part and is connected (25, 26, 27, 28) to the filter medium, and wherein the surface of the stiffening structure, which overlaps with the surface of the filter medium of the front part that is active as a filter, is smaller than the surface of the surface of the filter medium of the front part that is active as a filter.

9. Respiratory protection mask according to claim 8, wherein the film (22) of the stiffening structure of the front part (2) is arranged on the face-away side (14) of the front part or on the face-facing side (13) of the front part.

10. Respiratory protection mask according to claim 8 or 9, wherein the film (22) of the stiffening structure of the front part (2) has one or more recesses (221).

11. Respiratory protection mask according to one of claims 8 to 10, wherein the film (22) of the stiffening structure of the front part (2) is transparent.

12. Respiratory protection mask according to claim 11, wherein the filter medium (24) of the front part (2) has a recess (23) which is completely covered with the foil (22) of the stiffening structure of the front part, said foil sealingly closing said recess and wherein said film is transparent.

13. Respiratory protection mask according to claim 12, wherein the foil (22) of the stiffening structure of the front part (2) is sealingly connected (26) to the filter medium (26) along the circumference of the recess (23) of the filter medium (24) of the front part (2).

14. Respiratory protection mask according to claims 8 to 13, wherein the foil (22) of the stiffening structure of the front part (2) is connected to the filter medium along a line (25, 27) at the upper and/or lower outer edge of the front part.

15. A method of making a folded respirator, comprising the steps of:

providing (S21) a web of a flat filter medium (24,34,44);

Creation (S22) of the edge contours (35, 45) of an upper part (3) and a lower part (4) of a breathing mask (1), for example by ultrasonic welding (31, 41);

- Separating (S23a) the material lying outside the edge contours along the created edge contours (35, 45) of the upper part and the lower part;

- Placing (S24) a film web (22) on the filter medium web in the area of a front part (2) of the respirator;

Folding (S26) the web of filter media so that the portions of the top, bottom and front portions are superimposed;

Creation (S27) of a sealing connection (11,12,25,27,21,31',41') between the front part (2) and the upper part (3) and between the front part (2) and the lower part (4), for example by ultrasonic welding;

Separating (S30) the material lying outside the outer contours of the front part along the outer contours of the front part;

Providing the isolated, folded mask body (2,3,4) for further processing; wherein the laying of the web of film onto the web of filter medium takes place before or after the folding of the filter medium.

16. The method according to claim 15, wherein after the laying (S24) of the film web (22) on the filter medium web (24), the film is welded to the filter medium (S25).

17. The method according to claim 15 or 16, wherein before the laying (S24) of the film web (2p2) on the filter medium web (24), a recess (23) is cut out (S23b) in the web area of the front part (2). .