EP4015048A1 - Medical face mask - Google Patents

Abstract

The invention relates to a medical mouth-nose mask, having a rectangular filter element (1) for covering a mouth and/or nose area of a person, with opposite transverse and longitudinal edges (2, 3) and at least one opposite end that can be stretched elastically (7) having a headband (6) for attaching the filter element (1) to a person's head, one end (7) being attached to each transverse edge (2) associated with a longitudinal edge (3), so that the non-stretched headband (6) extends along the longitudinal edge (3), a length of the non-stretched headband (6) between the ends (7) corresponds to a length of the longitudinal edge (3) between the transverse edges (2), and the transverse edges (2) adjacent to the fasten ends (7) of the headband (6) spring back in the direction of the non-stretched headband (6).

Description

technical field

The invention relates to a medical mouth-nose mask, having a rectangular filter element for covering a mouth and/or nose area of a person with opposite transverse and longitudinal edges and at least one elastically stretchable headband having opposite ends for fastening the filter element to a head of the person, each transverse edge having an end attached associated with a longitudinal edge such that the unstretched headband extends along the longitudinal edge, and a length of the unstretched headband between the ends corresponds to a length of the longitudinal edge between the transverse edges. The invention also relates to a method for producing a medical mouth-nose mask, having a rectangular filter element for covering a mouth and/or nose area of a person, each having opposite transverse and longitudinal edges and at least one elastically stretchable headband having opposite ends for attachment the filter element on a head of the person having an end associated with a longitudinal edge of each lateral edge such that the unstretched headgear extends along the longitudinal edge, with a length of the unstretched headgear between the ends of a length of the longitudinal edge between the transverse edges corresponds to

Background of the Invention

Protective masks, masks for short, are used to protect the face, parts of it and the respiratory organs. As filter masks or fresh air masks, protective masks protect against gases, vapours, liquid mist, coarse and respirable fine dust, pathogens, viruses and/or annoying odours. Masks are differentiated, for example, in everyday masks, so-called makeshift masks made of fabric or community masks, as medical mouth and nose protection, MNS, for example according to EN 14683, filtering masks, for example according to EN 149, FFP1 mask, FFP2 mask, N95 mask , or FFP3 mask. The aforementioned FFP masks are usually used as part of personal protective equipment as part of occupational safety in areas where there are harmful substances in the air.

Such protective masks are usually attached to the head with a strap, which is guided either behind the ears or behind the head in order to fix a filter element of the mask to a person's mouth and/or nose area. Higher quality masks have two flexible head attachment straps, also called head straps, that are pulled over the head to secure the mask. Basically, in order to achieve a sufficient filtering effect, it is important that the protective mask can be attached to the head easily and in a defined and sealing manner.

A disadvantage of the aforementioned headbands, however, is that the rubber bands used have a technical limit, ie they can only be stretched by a certain factor compared to their non-stretched state, which defines a maximum head circumference. If you lengthen the headbands so that people with a larger head circumference can use the mask, the manufacturing process becomes more complex and the mask takes up much more space in the packaging. If not only the headband but also the filter element is lengthened, the lengthened filter element leads to an uncomfortable wearing comfort for many people.

Description of the invention

Proceeding from this situation, it is an object of the present invention to specify a mask which, compared to the masks known from the prior art, can be worn comfortably by people with a comparatively larger spectrum of head circumferences.

The object of the invention is solved by the features of the independent claims. Advantageous configurations are specified in the dependent claims.

• ein rechteckartiges Filterelement zum Bedecken einer Mund- und/oder Nasenpartie einer Person mit jeweils gegenüberliegenden Quer- und Längsrändern und
• wenigstens einem elastisch streckbaren, gegenüberliegende Enden aufweisenden Kopfband zum Befestigen des Filterelements an einem Kopf der Person, wobei
• an jedem Querrand einem Längsrand zugeordnet ein Ende befestigt ist, so dass sich das nicht-gestreckte Kopfband entlang des Längsrandes erstreckt,
• eine Länge des nicht-gestreckten Kopfbandes zwischen den Enden einer Länge des Längsrandes zwischen den Querrändern entspricht, und
• die Querränder neben den befestigen Enden des Kopfbandes in Richtung des nicht-gestreckten Kopfbandes zurückspringen.

Accordingly, the object is achieved by a medical mouth-nose mask having

• a rectangular filter element for covering a mouth and/or nose part of a person with respective opposite transverse and longitudinal edges and
• at least one elastically stretchable headband having opposite ends for securing the filter element to a head of the person, wherein
• one end is attached to each transverse edge associated with a longitudinal edge, so that the non-stretched headband extends along the longitudinal edge,
• a length of the unstretched headband between the ends corresponds to a length of the longitudinal edge between the transverse edges, and
• the transverse edges adjacent the fixed ends of the headgear spring back towards the unstretched headgear.

An essential point of the proposed mask lies in the fact that the filter element is not designed to be rectangular, but is set back at its transverse edges next to the attached flat ends. In the case of two headbands, the receding transverse edge is designed, for example, semi-elliptically, so that the longitudinal extent of the filter element is smaller in a central region between the opposite longitudinal edges than at the longitudinal edges. As a result of this, the mask has a greater extension at the head straps provided on the longitudinal edges and such longer head straps that are longer than the middle area. This means that with the same length in the middle area and the associated high wearing comfort due to the comparatively longer headbands, the proposed mask can also be worn by people with a larger head circumference and thus by a larger spectrum of head circumferences compared to the prior art.

In practice, it has also been shown that the proposed rectangular shape with receding transverse edges is better suited to sealing the filter element from the mouth and/or nose area than a rectangular shape known from the prior art. In other words, the proposed mask, while using the more comfortable form for medical mouth-nose masks, still allows the standard for particle-filtering FFP masks to be achieved, However, without having the form of an FFP mask that is less comfortable to wear in comparison.

Medical mouth and nose protection, abbreviated MNS, mask, also called medical mouth and nose mask, surgical mask, medical face mask, hospital mask, OP face mask or hygiene mask, is basically understood as a medical product to reduce the transmission of pathogens through secretion droplets . The filter element generally has three layers of non-woven fabric, of which the middle layer absorbs virus- and bacteria-carrying droplets with fibers that are significantly finer than the outer layers. The filter element should fit snugly against the mouth and/or nose of the person wearing the mask to filter both inhaled and exhaled air. For this purpose, the at least one elastically stretchable headband is provided, which can be guided around the head to fasten the filter element.

The headband is preferably designed as a rubber band, which is surrounded by a fabric, in particular a non-woven fabric, for increased wearing comfort. The opposite ends of the headband are attached to the opposite transverse edges, for example by welding, in particular ultrasonic welding, gluing or embossing. The headband preferably reaches up to the transverse edge and/or has a width of 10 or 15 mm. Correspondingly, the length of the unstretched headband between the ends equals the length of the longitudinal edge between the transverse edges means that the headband can be exactly the same length as the extension of the filter element at the transverse edge, but also up to 1%, 2%, 5% or 10% longer or shorter. The headband is preferably attached to the filter element only at its ends, so that by stretching the headband an opening is formed between the headband and the longitudinal edge, through which the head can be guided in order to attach the mask to it.

Set back means in particular that the transverse edges next to the fastened ends are set back in the direction of a center point of the filter element, for example are cut out in a semi-elliptical shape, so that the longitudinal extent of the filter element in the cut-out central area is less than at the longitudinal edges. With In other words, the headband extends longitudinally at the longitudinal edge beyond the recessed area. In the central, recessed area, the filter element preferably has a longitudinal extension of typically 175 mm, as is also usual with filter elements in masks known from the prior art. The proposed filter element and thus also the headbands have a longitudinal extent of typically 200 mm on the longitudinal edges, so that the transverse edges on the longitudinal edges project beyond the central, recessed area on both transverse sides by 12.5 mm each. Springing back next to the fastened ends of the headband means in particular that the transverse edge does not spring back in the area of the headband.

The mask is preferably designed as a respirator, in particular designed as a half mask, preferably for use as a filtering mask (FFP), in particular for preventing the inhalation of harmful particles and for reducing infection with pathogens through the mouth and/or nose, and/or for use in particular as an aerosol-filtering respiratory mask and/or filter particle mask, more particularly to prevent the transmission of pathogens by droplet infection and/or in particular to reduce a germ load, in particular a viral load, for example in the event of an epidemic or pandemic spread of infectious diseases such as COVID-19. The protective mask is preferably designed as a particle-filtering half mask in accordance with EN 149:2001 or EN 149:2001+A1:2009, in particular an FFP-1, FFP-2 or FFP-3 mask. Furthermore, the mask can be designed according to EN standards 136, 140, 143, 149, 1827, 12941 and/or 12942.

According to a preferred development, the mask has two headbands that are assigned to the opposite longitudinal edges. The headbands are preferably spaced apart and arranged opposite one another. Using the two headbands, the mask can be securely fastened to the upper back of the head and once to the lower back of the head.

According to another preferred development, the transverse edges recede in the shape of a semi-ellipse, a circle or a rectangle. The recessed area can be designed in this way, for example, in the manner of a semicircle. According to yet another preferred development the headband extends in the non-stretched state parallel and/or flush to the longitudinal edge and/or lies in contact with the filter element. The headband, also known as a head attachment band, is preferably designed as a textile, rubber-like, elastic and/or flat band, in particular as a flat band.

According to another preferred development, the filter element has several layers of non-woven material, which layers are connected to one another along the transverse and longitudinal edges and the connection of the transverse edges is set back next to the fastened ends of the headband. The layers are in particular provided on top of one another and are preferably glued, connected and/or sewn to one another. The layers can comprise a woven fabric, knitted fabric, knitted fabric, embroidered fabric, scrim and/or a textile composite, in particular a fleece or woven fabric. In this way, the filter element can consist of textile fibers and/or have textile fibers, with natural fibers, preferably wool or cotton, and/or synthetic fibers, preferably synthetic fibers (man-made fibers) such as cellulosic fibers, for example viscose fibers, being used as textile fibers, in particular made of the group of polyesters (PES), polyolefins such as polyethylene (PE) and polypropylene (PP), polyvinyl chloride (CLF), polyvinylidene chloride (CLF), acetate (CA), triacetate (CTA), polyacrylic (PAN), polyamide (PA) , polyvinyl alcohol (PVAL), polyurethanes, polyvinyl esters, (meth)acrylates and mixtures thereof. The aforementioned abbreviations for the textile fibers come from DIN 60001-4 (August 1991). The mask can contain further layers of fabric, for example as intermediate layers with different functions, for example for additional filtering, sealing, moisture absorption, etc.

Furthermore, for the purpose of the filtering effect, the filter element can have a flexible, porous fabric that belongs to the textile composites and is not produced by classic methods of weaving warp and weft or by knitting, but by intertwining and/or cohesive and/or adhesive connections of textile fibers . Fleeces are generally loose materials made from staple fibers or filaments, in particular from synthetic fibers or man-made fibers, for example polypropylene, polyester, viscose, etc., which are held together by the adhesion inherent in the fibers. Individual fibers can have a preferred direction, so-called oriented or cross-ply nonwovens, or they can also be non-directional, so-called tangled webs. The average diameter of the textile fibers of the filter element is preferably at most 100 μm, in particular at most 30 μm, preferably at most 20 μm, preferably at most 10 μm, particularly preferably at most 5 μm, very particularly preferably at most 2 μm. In general, the diameter of the textile fibers of the filter element should be in the range from 0.05 to 50 μm, in particular 0.1 to 50 μm, preferably 0.2 to 30 μm, particularly preferably 0.2 to 20 μm, very particularly preferably 0. 5 to 10 µm.

The nonwovens can be mechanically strengthened by needling, meshing or by swirling using sharp water jets, so-called spunlaced nonwovens. Nonwovens can also be produced, for example, by spunbonding, meltblow processes and preferably by electrospinning. Adhesively bonded nonwovens can be created by bonding the fibers with liquid binders, for example acrylate polymers, SBR/NBA, polyvinyl ester or polyurethane dispersions, or by melting or dissolving so-called binding fibers that are mixed into the nonwoven during manufacture. In the case of cohesive bonding, the fiber surfaces are dissolved using suitable chemicals and connected by pressure or welded at elevated temperatures. Nonwovens made from so-called spunbonded nonwovens, i.e. fabrics produced by spinning and then depositing, inflating or sponging onto a conveyor belt, are called spunbonded nonwovens. The shape of the filter element can be adapted to the person's face to form a so-called CUP mask or be designed to be foldable to form a so-called folding mask.

The filter element can have an average pore size or average mesh size—depending on the type of fabric layer—of greater than 1 μm, in particular greater than 10 μm, preferably greater than 50 μm, particularly preferably greater than 100 μm, or more than 200 μm. In this way, a good separation rate with regard to particles and aerosols and/or a low breathing resistance can be achieved. Furthermore or additionally, the filter element can comprise an electrostatic material, in particular an electret, through which small dust particles and liquid droplets can be bound by electrostatic forces. The ratio or the quotient of the average pore size or mesh size to the average diameter of the textile fibers of the filter element is particularly preferably in the range from 0.1 to 2000, especially 1 to 500, preferably 5 to 350, more preferably 10 to 300, most preferably 25 to 250. In particular, the ratio or the quotient of the average pore size or mesh size to the average diameter of the textile fibers of the filter element should be no more than 2,000, in particular no more than 500, preferably no more than 350, particularly preferably no more than 300, very particularly preferably no more than 250. However, the ratio or the quotient of the average pore size or mesh size to the average diameter of the textile fibers of the filter element should be at least 0.1, in particular at least 1, preferably at least 5, particularly preferably at least 10, very particularly preferably at least 25, even more preferably at least 40 , amount. In this way, particularly efficient separation rates with regard to pathogens and aerosols are achieved.

In order to achieve an efficient separation rate with regard to pathogens, the filter element can have an average efficiency Em according to DIN EN 779 (July 1993) of at least 40%, in particular at least 50%, preferably at least 70%, particularly preferably at least 90%, very particularly preferably at least 95%. For this purpose, the filter element can also have an average degree of separation Am according to DIN EN 779 (July 1993) of at least 50%, in particular at least 70%, preferably at least 90%, particularly preferably at least 95%, very particularly preferably at least 99%. The filter element is advantageously designed in such a way that, at an inflow velocity of 0.1 m/s, it has an average separation rate of at least 80%, in particular at least 90%, preferably at least 95%, for particles and/or aerosols with diameters in the range from 1 to 100 µm %, having.

According to yet another preferred development, the mask has a foam bracket which is arranged centrally on one of the longitudinal edges. The foam bracket can have an integrated flexible metal bracket which is integrated into the longitudinal edge. The foam bracket allows the mask to be adapted to the bridge of the nose in order to keep a field of vision free and to minimize the entry and exit of breathing air upwards, so that the filter element rests in particular around the mouth and/or nose area.

• ein rechteckartiges Filterelement zum Bedecken einer Mund- und/oder Nasenpartie einer Person mit jeweils gegenüberliegenden Quer- und Längsrändern und
• wenigstens einem elastisch streckbaren, gegenüberliegende Enden aufweisenden Kopfband zum Befestigen des Filterelements an einem Kopf der Person, mit dem Schritt:
  • Befestigen an jedem Querrand einem Längsrand zugeordnet ein Ende, so dass sich das nicht-gestreckte Kopfband entlang des Längsrandes erstreckt, wobei
  • eine Länge des nicht-gestreckten Kopfbandes zwischen den Enden einer Länge des Längsrandes zwischen den Querrändern entspricht, und
  • die Querränder neben den befestigen Enden des Kopfbandes in Richtung des nicht-gestreckten Kopfbandes zurückspringen.

The object is also achieved by a method for producing a medical mouth-nose mask

• a rectangular filter element for covering a mouth and/or nose part of a person with respective opposite transverse and longitudinal edges and
• at least one elastically stretchable headband having opposite ends for attaching the filter element to a head of the person, comprising the step of:
  • Attaching to each transverse edge an end associated with a longitudinal edge such that the unstretched headband extends along the longitudinal edge, wherein
  • a length of the unstretched headband between the ends corresponds to a length of the longitudinal edge between the transverse edges, and
  • the transverse edges adjacent the fixed ends of the headgear spring back towards the unstretched headgear.

The end is attached to the transverse edge, for example by gluing, welding, sewing or embossing. The end is connected to the filter element in particular in a planar manner, for example in a square end area.

According to a preferred development, the method has the step:
Shorten the transverse edges adjacent to the attached ends of the headgear in the direction of the unstretched headgear to obtain the recessed transverse edges.

The shortening can be done by punching, cutting out or lasering, in particular in an automated process. Alternatively, the filter element can already be provided as a starting material in the form of a rectangle with receding transverse edges.

According to another preferred development, the method has the step:
Half-elliptical, circular or rectangular shortening of the transverse edges.

According to yet another preferred development, the filter element has several layers of nonwoven fabric and the method has the following step:
Joining the layers together along the lateral and longitudinal edges, the joining of the lateral edges springing back adjacent the attached ends of the headband. According to another preferred development, in the unstretched state, the headband extends parallel and/or flush to the longitudinal edge and/or lies in contact with the filter element.

Further configurations and advantages of the method result for the person skilled in the art in analogy to the mask described above.

Brief description of the drawings

The invention is explained in more detail below with reference to the accompanying drawings using preferred exemplary embodiments.

Fig. 1

aus dem Stand der Technik bekannte medizinische Mund-Nasen-Maske in rückseitiger Draufsicht,

Fig. 2

eine medizinische Mund-Nasen-Maske gemäß einem bevorzugten Ausführungsbeispiel in vorderseitiger Draufsicht, und

Fig. 3

die medizinische Mund-Nasen-Maske gemäß dem bevorzugten Ausführungsbeispiel in rückseitiger Teildraufsicht.

Show in the drawings

1

medical mouth-nose mask known from the prior art in rear plan view,

2

a medical mouth-nose mask according to a preferred embodiment in a front plan view, and

3

the medical mouth-nose mask according to the preferred embodiment in a rear partial top view.

Detailed description of the exemplary embodiments

1 shows a rear plan view of a medical mouth-nose mask known from the prior art, which has a filter element 1 for covering a part of the mouth and/or nose of a person. The filter element 1 has a rectangular, flat shape with linearly extending transverse and longitudinal edges 2, 3 opposite each other.

The filter element 1 consists of three rectangular layers 4 of non-woven fabric, of which the middle layer 4 has much finer tangled fibers than the outer layers 4 in order to absorb droplets carrying viruses and bacteria. The outer layers 4 have spunbond materials, while the middle layer is made using the meltblown process. Likewise, the filter element 1 can only have two layers 4, with the meltblown layer 4 being provided on the outside. The individual layers 4 of nonwoven fabric extend up to the transverse and longitudinal edges 2, 3. Along the circumference and spaced apart from the transverse and longitudinal edges 2, 3, the layers 4 of nonwoven fabric are connected to one another in a stationary manner by means of an embossing 5. In the present case, the embossing 5 is carried out by stamping, but it can also include gluing or welding or sewing.

The mask also has two elastically stretchable head straps 6, by means of which the filter element 1 can be attached to a person's head. The opposite ends 7 of the headbands 6 are attached to the opposite transverse edges 2 of a respective longitudinal edge 3 by means of embossing 5 . The length of each non-stretched headband 6 between the ends 7 corresponds to a length of the longitudinal edge 3 between the transverse edges 2, so that the non-stretched headband 6 extends along the longitudinal edge 3, as shown in the lower figure in 1 illustrated headband 6 can be seen. In this way, in the non-stretched state, the headband 6 extends parallel and flush to the upper longitudinal edge 2 and lies in contact with the filter element along its extension. The upper in 1 The headband 6 shown is lifted off the filter element 1 by one of the person's hands and stretched in such a way that the mask can be placed on the head with an opening formed between the stretched headband 6 and the longitudinal edge 3 and clamps on the head to attach it to the head.

2 shows a medical mouth-nose mask according to a preferred embodiment in a front plan view. In the 2 The mask shown is analogous to that in 1 Mask designed, for example, with three layers of 4 non-woven fabric. However, the transverse edges 2 of the in 2 shown mask next to the attached ends 7 of the headband 6 in the direction of the non-stretched headband 6, so that the transverse edges 2 opposite the linear extension in 1 now a semi-elliptical shape directed towards the center of the filter element 1 between the respective ends 7 of the headbands Have 6 on each transverse edge 2. Alternatively, the two transverse edges 2 can also be set back in the form of a circle or a rectangle towards the center point of the filter element 1 .

In the 1 The mask shown has a length of 175 mm along each of its longitudinal edges 3 . The headbands 6 have the same extension of 175 mm. In the 2 The mask shown also has a longitudinal extension of 175 mm between the transverse edges 2 and between respective ends 7 of the headbands 6, as shown in FIG 3 seen in the mask of 2 shown in rear view. In contrast, the in 2 shown mask along their longitudinal edges 3 each have a longitudinal extension of 200 mm. The headbands 6 also have a length of 200 mm in the non-stretched state.

The proposed in 2 The mask shown is therefore longer in the area of the longitudinal edges 3 than in 1 shown mask known from the prior art, while the mask in the central area between the respective ends 7 of the headbands 6 is the same size at a transverse edge 2 or narrower compared to the longitudinal edges 3. As a result, the proposed mask can also be worn by people with a larger head circumference, with the fit of the mask in the middle area being just as comfortable. The proposed mask is therefore not rectangular in plan view but rather rectangular in shape, which allows for longer headbands 6 with a narrower shape with a central area. In this way, due to the narrow shape, the proposed mask lies close to the person's face in the central area and filters both inhaled and exhaled air. Correspondingly, the embossing 5 jumps back to connect the transverse edges 3 next to the fastened ends 7 of the headband 6 .

As rudimentarily in 3 indicated, the mask also has a foam bracket 8 which is arranged centrally on one of the longitudinal edges 3 . The foam bracket 8 has an integrated, flexible metal bracket, by means of which the filter element 1 can be adapted to the bridge of the person's nose, in order to keep the person's field of vision free and to minimize breathing air entering and exiting upwards.

To produce the mouth-nose mask, first the rectangular filter element 1 for covering the mouth and/or nose area of the person with opposite transverse and longitudinal edges 2, 3 and at least one elastic, stretchable headband 6 for fastening the filter element 1 to the head of the person with opposite ends 7 are provided. In a first step, an end 7 assigned to a longitudinal edge 3 of each transverse edge 2 is attached by means of an embossing 5, so that the non-stretched headband 6 extends along the longitudinal edge 3 and the length of the non-stretched headband 6 between the ends 7 of the Length of the longitudinal edge 3 between the transverse edges 2 corresponds. In a second step, the transverse edges 2 next to the fastened ends 7 of the headband 6 are shortened in the direction of the non-stretched headband 6 in order to obtain the recessed transverse edges 2 in the manner of a semi-ellipse.

The exemplary embodiments described are merely examples that can be modified and/or supplemented in many ways within the scope of the claims. Each feature described for a particular embodiment can be used on its own or in combination with other features in any other embodiment. Each feature described for an embodiment of a particular category can also be used in a corresponding manner in an embodiment of another category.

Reference List

filter element 1 cross border 2 long edge 3 location 4 embossing 5 headband 6 End 7 foam hanger 8th

Claims (11)

Medical mouth and nose mask, having a rectangular filter element (1) for covering a person's mouth and/or nose with opposite transverse and longitudinal edges (2, 3) and at least one elastically stretchable headband (6) having opposite ends (7) for attaching the filter element (1) to a head of the person, wherein one end (7) assigned to a longitudinal edge (3) is attached to each transverse edge (2), so that the non-stretched headband (6) extends along the longitudinal edge (3), a length of the unstretched headband (6) between the ends (7) corresponds to a length of the longitudinal edge (3) between the transverse edges (2), and the transverse edges (2) next to the fixed ends (7) of the headband (6) recede in the direction of the non-stretched headband (6). Mask according to the preceding claim, comprising two headbands (6) associated with opposite longitudinal edges (3). Mask according to one of the preceding claims, wherein the transverse edges (2) are set back in the manner of a semi-ellipse, a circle or a rectangle. Mask according to one of the preceding claims, wherein the headband (6) in the non-stretched state extends parallel and/or flush with the longitudinal edge (3) and/or lies in contact with the filter element (1). Mask according to one of the preceding claims, wherein the filter element (1) has several layers (4) of nonwoven fabric, which layers (4) are connected to one another along the transverse and longitudinal edges (2, 3) and the connection of the transverse edges (2) adjacent to the fasten the ends (7) of the headband (6) springs back. Mask according to one of the preceding claims, with a foam bracket (8) which is arranged centrally on one of the longitudinal edges (3). Method for producing a medical mouth-nose mask, comprising a rectangular filter element (1) for covering a person's mouth and/or nose with opposite transverse and longitudinal edges (2, 3) and at least one elastically stretchable headband (6) having opposite ends (7) for attaching the filter element (1) to a head of the person, comprising the steps of; Attaching to each transverse edge (2) associated with a longitudinal edge (3) an end (7) so that the unstretched headband (6) extends along the longitudinal edge (3), wherein a length of the unstretched headband (6) between the ends (7) corresponds to a length of the longitudinal edge (3) between the transverse edges (2), and the transverse edges (2) next to the fixed ends (7) of the headband (6) recede in the direction of the non-stretched headband (6). Method according to the preceding method claim, with the step:
Shortening the transverse edges (2) next to the fixed ends (7) of the headband (6) in the direction of the non-stretched headband (6) to obtain the recessed transverse edges (2). Method according to the preceding method claim, with the step:
Shortening of the transverse edges in the form of a semi-ellipse, a circle or a rectangle (2). Method according to one of the preceding method claims, wherein the filter element (1) has several layers (4) of nonwoven fabric, with the step:
Joining the layers (4) together along the transverse and longitudinal edges (2, 3), the junction of the transverse edges (2) springing back adjacent the fixed ends (7) of the headband (6). Method according to one of the preceding method claims, in which the headband (6) in the non-stretched state extends parallel and/or flush with the longitudinal edge (3) and/or lies in contact with the filter element (1).

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