FR3111771A1 - FILTERING MASK - Google Patents

Abstract

The present invention relates to a filtering mask (1) for protecting an individual against the inhalation of infectious agents transmissible by air, characterized in that it comprises:- a frame (10) adapted to be positioned on the face of the individual, said frame (10) comprising a cavity (16) capable of receiving at least the nose and the mouth of the individual, a peripheral part (13) adapted to come into contact with the face of the individual in a waterproof manner the air, and a through orifice (17) placing the cavity and the outside of the frame in communication, - a first filter (20), comprising a textile material, adapted to be positioned against an external face (14) of the frame so as to cover at least the through hole (17) and hold the frame in place, said first filter ensuring a first filtration of an incoming air flow,- a second filter (30), adapted to be positioned in the through hole (17), said second filter providing second filtration of the incoming air flow, in which the first filter (20) and the second filter (30) are adapted to be removably positioned on the frame (10). Figure for abstract: Fig. 2

Description

FILTERING MASK

Technical field of the invention

The present invention relates to a filtering mask making it possible to protect an individual against the inhalation of infectious agents transmissible by air.

Technology background

Respiratory protection masks are classified into two general categories: surgical masks, and filtering masks commonly called FFP (“Filtering Face Piece”).

A surgical mask is a medical device. This type of mask makes it possible to avoid the projection towards people near the individual wearing the mask, of the droplets emitted by this individual. This type of mask also protects the individual wearing the mask against the projection of droplets emitted by people nearby. On the other hand, it does not protect against the inhalation of very small particles in suspension in the air, of the order of a few micrometers, which can correspond to infectious agents transmissible by air.

A filter mask is a respiratory protective device. This type of mask protects the individual wearing the mask against inhalation of both droplets and airborne infectious agents.

Wearing a filter mask is restrictive, since it causes breathing difficulties. Indeed, the air inspired by the individual wearing the mask is filtered by the mask filter, which already represents an additional respiratory effort compared to breathing without a mask. The exhaled air is partially blocked by the mask, and by a peripheral seal which provides a theoretical seal between the mouth of the individual and the external environment. Thus, the exhaled air accumulates at the level of the nose and the mouth of the individual, both covered by the mask, thus limiting the expiration and therefore the breathing of the individual.

In addition to respiratory discomfort, wearing a filter mask causes thermal discomfort, since the exhaled air that accumulates in the nose and mouth of the individual is hot air. The accumulation of hot air also causes humidification of the mask, which is very unpleasant for the individual.

In addition, once the mask has been used, it must be thrown away, when it is a single-use mask. In addition to being impractical, this generates large amounts of waste, and incurs significant expenses for users who are forced to acquire large quantities of masks.

When the mask is reusable, it is necessary to wash it. The mask then becomes unusable during washing and drying, and it is therefore necessary to use another mask while waiting to be able to reuse the first mask.

Brief description of the invention

An object of the invention is to provide a filtering mask that makes it possible to overcome the drawbacks mentioned above.

The invention aims in particular to provide a filtering mask which is more comfortable to wear, in particular by reducing the discomfort usually caused by the wetting of the mask caused by the breathing of the user.

The invention aims in particular to provide a filtering mask, allowing the individual who wears the mask to maintain a good level of breathing.

Another object of the invention is to provide a filtering mask making it possible to reduce the quantities of waste generated when the masks are thrown away, while reducing the costs of using these masks.

To this end, the invention proposes a filtering mask to protect an individual against the inhalation of infectious agents transmissible by air, mainly characterized in that it comprises:
- a frame adapted to be positioned on the face of the individual, said frame comprising a cavity capable of receiving at least the nose and the mouth of the individual, a peripheral part adapted to come into contact with the face of the individual of airtight manner, and a through orifice placing the cavity and the outside of the frame in communication,
- a first filter, comprising a textile material, adapted to be positioned against an outer face of the frame so as to cover at least the through hole and hold the frame in place, said first filter ensuring a first filtration of a incoming air flow,
- a second filter, adapted to be positioned in the through hole, said second filter providing a second filtration of the incoming air flow,
wherein the first filter and the second filter are adapted to be removably positioned on the frame.

The frame makes it possible to maintain a space between the first filter (and the second filter which is housed in the frame), and the face of the individual. This makes the mask more comfortable to wear by reducing the discomfort usually caused by the wetting of a textile filter caused by the individual's breathing, while ensuring the individual a good level of breathing. The first filter and the second filter are of course in fluid communication (air) with each other. The air exhaled by the individual is routed from the cavity to the external environment, successively passing through the second filter via the through hole and then the first filter.

The peripheral part of the frame prevents the passage of air at the edge of the mask, that is to say between said peripheral part of the frame and the face of the individual. The air is therefore forced to pass through the first filter and the second filter, thus ensuring optimal protection of the individual against the inhalation of infectious agents transmissible by air.

As indicated above, the first filter and the second filter are removably positioned on the frame. In other words, the frame, the first filter, and the second filter are three separable parts adapted to form the mask of the invention when they are assembled. These three parts make it possible to obtain a modular mask: each of the first filter, second filter, and frame can be individually separated from the other parts, in particular to be washed and then repositioned, or replaced by another similar part. This significantly reduces waste and cost of using the mask.

The first filter provides a first filtration of the airflow on inspiration, and the second filter provides a second filtration of the airflow already filtered by the first filter. The use of a second filter thus makes it possible to further improve the filtration rate compared to the first filter alone positioned on the frame.

In addition, the second filter clogs much less quickly thanks to the presence of the first filter, since the latter already filters most of the particles, in particular the larger particles. The second filter therefore needs to be washed or replaced less often.

According to other aspects, the filtering mask according to the invention has the following different characteristics taken alone or according to their technically possible combinations:

• the frame comprises a material chosen from: polyamide, polypropylene, polyester, polyvinyl chloride, polycarbonate, polyethylene, silicone, or mixtures thereof;
• the first filter comprises one or more straps making it possible to hold the first filter in position on the face of the individual, said strap being attached to the first filter, for example sewn to the first filter, or said strap being in one piece with the first filter;
• the first filter comprises a knit of threads filtering at least 98% of the particles of characteristic size greater than or equal to 3 micrometers;
• the second filter comprises a textile material. The textile material of the second filter can be identical to or different from that of the first filter;
• the second filter includes an activated carbon filter;
• one or more of the frame, the first filter, and the second filter, is washable and reusable;
• the first filter is in the form of a one-piece knitted tubular headband, adaptable to the morphology of the individual's head, the tubular headband comprising a front part adapted to at least partially cover the frame and a rear part adapted to come to rest against the neck of the individual, and in which the strap is in one piece with the headband and corresponds to the rear part of said headband. In this case, the flange is an integral part of the first filter. The first filter and the flange are knitted in one piece, and there is no seam between the flange and the first filter;
• the through hole is adapted to face the mouth of the individual when the frame is positioned on the face of the individual;
• the filtering mask does not have an air outlet valve. The masks provided with valves are typically FFP3 masks which are intended to protect the wearer against the inhalation of dust, gas or toxic vapor, which is not the case of the mask of the invention. The latter ensures good breathability of the individual without the need for a valve. Indeed, the frame allows to have a space of several centimeters between the face and the filters.

Description of figures

Other advantages and characteristics of the invention will appear on reading the following description given by way of illustrative and non-limiting example, with reference to the following appended figures:

is a perspective view of one embodiment of the filtering mask according to the invention;

is an exploded perspective view of the filter mask of Figure 1;

is a perspective view of the frame alone positioned on the individual's face;

is another perspective view of the frame alone positioned on the individual's face;

is a side view of an embodiment of the first filter, according to which said first filter is in the form of a band; in this case the flange is an integral part of the filter.

Detailed description of embodiments of the invention

The invention relates to a filtering mask for protecting an individual wearing the mask against the inhalation of infectious agents transmissible by air. The mask also protects the individual and the people close to him against the transmission of infectious agents transmissible by way of droplets, unlike a mask containing a valve. In fact, in the case of a mask fitted with a valve, the user can contaminate nearby people during exhalation, because the valve blocks the flow of air during inspiration but allows the flow to pass. of air during exhalation.

An embodiment of the mask of the invention is shown in Figures 1 and 2.

The filter mask 1 comprises three parts adapted to be assembled together, including an armature 10, a first filter 20, and a second filter 30.

The frame 10 is adapted to be positioned on the face of the individual, so as to cover at least the nose and the mouth of the individual. The armature 10 is shown in more detail in Figures 3 and 4.

The frame 10 is a structural part which acts as a support for the first filter 20 and the second filter 30. The frame, also referred to as a support structure or a support shell, is defined as being a structure having a sufficient structural integrity to retain its original shape when using the filter mask.

To this end, the frame 10 is preferably rigid or at least slightly deformable by applying pressure from the individual, in particular when positioning the filtering mask on the face of the individual.

The frame 10 is preferably in the form of a solid piece, except for the housing used to accommodate the second filter which will be described in more detail later in this text. This gives better mechanical strength to the frame, compared to a perforated frame and guarantees sealing against the external environment and therefore optimal protection of the individual.

The frame 10 comprises a main part 11, and a peripheral part 13 adapted to come into contact with the face of the individual in a sealed manner. Further, the armature includes an outer surface 14, and an inner surface 15 opposite the outer surface with respect to the armature.

As shown in particular in Figure 4, the frame 10 is bulging, that is to say convex. The vertex 18 of the convex curvature of the frame is directed in the opposite direction to the face of the individual. The bulge of the armature 10 defines a cavity 16 delimited by the inner surface 15 of the armature. The cavity 16 is adapted to receive the face of the individual, in particular his nose and his mouth.

As illustrated in Figures 2, 3 and 4, the frame 10 includes a through hole 17, formed in the thickness of the frame. The through hole 17 is advantageously located at the level of the top 18 of the main part 11 of the frame, facing the mouth of the individual when the mask is worn.

The through hole 17 is a housing adapted to receive the second filter 30, the latter being described in more detail later in this text.

Preferably, the frame 10 further comprises a grid 12 arranged in the through orifice 17. The grid includes openings 19 which allow the circulation of air from the outside to the inside of the filter mask, this is i.e. in the direction of inspiration, and also from the inside out, i.e. in the direction of expiration.

The frame 10 preferably comprises a material chosen from: polyamide, polypropylene, polyester, polyvinyl chloride, polycarbonate, polyethylene, silicone, or mixtures thereof. These materials provide a frame 10 that meets the structural integrity requirements of the frame.

Preferably, the peripheral part 13 of the frame 10 comprises a material comprising at least one silicone polymer. A silicone material ensures a soft contact between the filtrate mask and the face of the individual, makes the filter mask comfortable for the individual, while ensuring an optimal seal of the cavity 16 to the outside air.

Referring to Figures 1 and 2, the first filter 20 is in the form of a layer of textile material adapted to be positioned on the outer surface 14 of the frame 10 so as to cover said frame.

The first filter 20 comprises a filtering part 21 which ensures the filtration of the infectious agents transmissible by air. The filtering part 21 can be arranged over the entire surface of the first filter, or over only part of the first filter. The filtering part 21 is arranged at least on a central part 22 of the first filter which is intended to cover the through hole 17 of the frame 10.

Once positioned on the frame 10, the first filter 20 at least partially covers the main part 11 of the frame, thus covering the through hole 17. The first filter 20 also covers, preferably, the chin of the individual , in order to cover the entire lower part of the individual's face. The first filter 20 can extend beyond the peripheral part 13 of the frame and at least partially cover the cheeks and cheekbones of the individual, as shown in Figure 1.

The first filter 20 conforms at least in part to the frame 10, and remains in this conformation when using the filter mask.

The first filter 20 is adapted to be removably positioned against the frame 10. This means that the individual can position the first filter against the frame or remove the first filter from the frame, and this in a simple and rapid manner. , taking the first filter in hand and moving it relative to the armature. In other words, the frame 10 and the first filter 20 are two separate parts capable of being assembled one on the other to use the mask of the invention.

Therefore, when the first filter 20 is dirty, it is possible to separate it from the frame 10 in order to wash it, then to reposition it on the frame. Alternatively, it is possible to position a new first filter on the armature. The frame itself can be washed separately from the first filter.

According to one embodiment, the first filter 20 comprises flanges 23 comprising one end connected to the peripheral part 13, and a free end adapted to be attached to the head of the individual, for example to the ears of the individual.

The flanges 23 make it possible to maintain the first filter 20 in position on the face of the individual.

The flanges 23 can be attached, for example sewn to the first filter 20, or else be in one piece with the first filter 20, that is to say seamless.

Preferably, the first filter makes it possible to maintain the frame 10 in position against the face of the individual, by applying a force on said frame oriented towards the face of the individual, when it is attached to the head of the individual via flanges 23.

The straps 23 include, for example, straps adapted to be wrapped around the head of the individual and tied together behind the head at the level of the occiput. It can also be straps forming loops suitable to be positioned around the ears of the individual. They can also be adhesive strips, in particular of the Velcro® type, adapted to be wrapped around the head of the individual and glued to each other behind the head at the level of the occiput.

According to an embodiment illustrated in FIG. 5, the first filter 20 is in the form of a one-piece knitted tubular strip. In this embodiment, the flange 23 is an integral part of the first filter 20.

Preferably, the first filter 20 in the form of a band is symmetrical between the left and right sides, and asymmetrical between the front 24 and the rear 25, with a maximum height on the front and a minimum on the rear. For example, the back height is about two-thirds the front height of the headband. Thus, the headband is higher in the front part 24 provided to cover the face of the individual.

Still according to this embodiment, the first filter 20 in the form of a band is preferably elastic (under normal conditions of temperature and pressure CNTP), which gives it a capacity for morphological adaptation to the head of the individual, especially his face.

The headband 20 includes a through opening to pass the head. Once put on, the headband rests forward on the individual's face, covering the nose, mouth and chin, and rests backward on the individual's neck.

In the case of a headband, the flange 23 is an integral part of the headband, and corresponds to the rear part 25 of the headband, intended to bear against the neck of the individual.

The filtering part 21 of the first filter 20 preferably comprises a knit of elastic threads (in CNTPs), the materials and arrangement of which make it possible to obtain the following performances:

- filtration of 3 µm particles greater than 98%;

- filtration of particles of 1 µm greater than 94%;

- filtration of fine particles of 0.2 µm greater than 60%;

- air permeability greater than 150 l/m².s-1 under a depression of 100 Pa.

These performances allow a classification of the mask in category 1: individual mask for professionals in contact with the public (classification of barrier masks AFNOR SPEC S76-001).

Preferably, the first filter 20 comprises at least 95% by weight of polyamide and elastane fibers, preferably at least 99%. In other words, the filtering part 21 of the first filter 20 mainly comprises polyamide and elastane, but may comprise other materials. More precisely, the filtering part 21 comprises between 85 and 95% by mass of polyamide and between 5 and 15% by mass of elastane.

Preferably, at least the filtering part 21 of the first filter 20 comprises an antibacterial treatment. For simplicity, the entire first filter 20 may comprise an antibacterial treatment. The treatment can be carried out on the threads constituting the first filter during the manufacture of the mask, or on the finished mask.

The second filter 30 is adapted to be positioned in the through hole 17 forming a housing in the main part of the frame 10.

The second filter 30 is completely configurable, that is to say it can be any type of filter, which is chosen according to the filtration performance desired for the combination of the first filter of the second filter.

The second filter 30 is adapted to be removably positioned on the frame 10. This means that the individual can position the second filter on the frame or remove the second filter from the frame, and this in a simple and fast manner. , taking the second filter in hand and moving it relative to the armature. In other words, the frame 10 and the second filter 30 are two separate parts able to be assembled with each other to use the mask of the invention.

Therefore, when the second filter 30 is dirty, it is possible to separate it from the frame 10 in order to wash it, then to reposition it on the frame. Alternatively, it is possible to position a new second filter on the frame. The frame itself can be washed separately from the second filter.

The second filter 30 makes it possible to further improve the filtration rate compared to the first filter 20 alone positioned on the frame.

In particular, when the first filter 20 filters at least 98% of the particles of characteristic size greater than or equal to 3 micrometers, the second filter 10 can be adapted to filter at least part of the remaining 2% of particles of characteristic size greater than or equal to to 3 micrometers, and at least a part of the particles of characteristic size less than 3 micrometers.

In addition, the second filter 30 becomes clogged much less quickly thanks to the presence of the first filter, since the latter already filters the majority of the particles, in particular the larger particles.

Preferably, the second filter 30 is an activated carbon filter.

Alternatively, the second filter 30 is preferably a textile filter. The textile material of the second filter 30 can be chosen from among the materials described above for the first filter 20. The textile material of the second filter 30 can be identical to or different from that of the first filter 20.

As described above, the frame 10, the first filter 20, and the second filter 30 are in the form of separate parts suitable for being assembled to form the mask 1.

The mask 1 according to the invention is modular, and it is thus possible:
- assembling the armature 10, the first filter 20, and the second filter 30, to use the mask, or
- assemble only the frame 10 and the first filter 20, to use the mask, without the second filter 30.

This modularity makes it possible to precisely modulate the filtration rate of the mask: use only the first filter 20 for standard filtration, or use the second filter 30 in addition to the first filter 20 to obtain a higher filtration rate.

The use of the first filter 20 and second filter 30 can in particular make it possible to obtain an FFP2 type filter, which is characterized by a percentage of filtration of aerosols of average size 0.6 μm of at least 94%, and a rate of inward leakage less than or equal to 8%, according to European standards EN 143 and EN 149.

This modularity also makes it possible to individually wash or replace the frame 10, the first filter 20, or the second filter 30, without having to wash or replace the entire mask.

Furthermore, the mask according to the invention does not include an inspiratory or expiratory valve (also called a valve). Indeed, this type of valve improves the breathability of masks whose filters are pressed against the mouth of the individual, and masks with a high filtration rate. In the mask of the invention, good breathability is already ensured by the frame 10 which leaves a space between the first textile filter 20 and the face of the individual, via the cavity 16.

With regard to the operation of the mask, during inspiration, the air circulates from the external environment, passes through the first filter 20 then the second filter 30, until it reaches the cavity 16 then at the level of the nose or the individual's mouth. During expiration, the air circulates from the cavity 16, crosses the second filter 30 then the first filter 20, until reaching the external environment. Thus, the inspired air and the expired air take the same path, in two opposite directions, without crossing a valve.

Claims (9)

Filtering mask (1) to protect an individual against the inhalation of infectious agents transmissible by air, characterized in that it comprises:
- a frame (10) adapted to be positioned on the face of the individual, said frame (10) comprising a cavity (16) capable of receiving at least the nose and the mouth of the individual, a peripheral part (13) adapted to come into contact with the face of the individual in an airtight manner, and a through orifice (17) communicating the cavity and the outside of the frame,
- a first filter (20), comprising a textile material, adapted to be positioned against an outer face (14) of the frame so as to cover at least the through hole (17) and hold the frame in place, said first filter ensuring a first filtration of an incoming air flow,
- a second filter (30), adapted to be positioned in the through hole (17), said second filter providing a second filtration of the incoming air flow,
wherein the first filter (20) and the second filter (30) are adapted to be removably positioned on the frame (10). Filtering mask (1) according to Claim 1, characterized in that the frame (10) comprises a material chosen from: polyamide, polypropylene, polyester, polyvinyl chloride, polycarbonate, polyethylene, silicone, or mixtures thereof. Filtering mask (1) according to Claim 1 or Claim 2, characterized in that the first filter (20) comprises one or more flanges (23) making it possible to hold the first filter (20) in position on the face of the individual , said flange (23) being attached to the first filter (20) or said flange (23) being integral with the first filter (20). Filtering mask (1) according to any one of the preceding claims, characterized in that the first filter (20) comprises a knit of threads filtering at least 98% of the particles of characteristic size greater than or equal to 3 micrometers. Filtering mask (1) according to any one of the preceding claims, characterized in that the second filter (30) comprises a textile material. Filter mask (1) according to any one of claims 1 to 4, characterized in that the second filter (30) comprises an activated carbon filter. Filter mask (1) according to any one of the preceding claims, characterized in that one or more of the frame (10), the first filter (20), and the second filter (30), is washable and reusable. Filtering mask (1) according to any one of the preceding claims in combination with claim 3, characterized in that the first filter (20) is in the form of a one-piece knitted tubular band, adaptable to the morphology of the head of the individual, the tubular headband comprising a front part (24) adapted to at least partially cover the frame (10) and a rear part (25) adapted to bear against the neck of the individual , and wherein the flange (23) is in one piece with the headband and corresponds to the rear part (25) of said headband. Filtering mask (1) according to any one of the preceding claims, characterized in that the through orifice (17) is adapted to face the mouth of the individual when the frame (10) is positioned on the face of the individual.