NOVEL AIRTIGHT PROTECTIVE MASK

BACKGROUND OF THE INVENTION
Technical Field

The present invention is related to a mask, and in particular, to a novel airtight protective mask.

Description of Related Art

In recent years, due to the rapid development of industries and cities, waste gases are exhausted by various factories, coal-fired power plants and large amount of vehicles and motorcycles, causing serious air pollution. The haze (fine suspended particles PM2.5), pollen and dust in the environment are able to enter human bodies via respiratory tracks, leading to decrease of human immunity and various types of diseases, such that the human health is significantly affected. In particular, the World Health Organization (WHO) announced in 2013 that among the top ten causes of death, seven of such causes were closely related to air pollution, promoting countries around the world to enhance their prevention against haze while stimulating the general public to wear various types of masks. The WHO further published a report on Oct. 29, 2018, indicating that about 93% of the world's population, equivalent to 1.8 billion children under the age of 15, were exposed to air pollution, and this was a stunning news to all sectors around the globe.

In view of the serious health hazards caused by haze PM2.5, China formulated and published national standards for haze preventive masks in 2016/2017 in accordance with the standards for U.S. N95 series of masks and European FFP dust masks. However, according to the test method of D2 tightness of China National Standards CNS14774 and 14755 protective masks (N95/FFP), the mask tightness must be able to reach 100. However, according to the one-hundred-people test from the Taiwan Institute of Labor (Institute of Labor, Occupational Safety and Health), the average tightness values of the two types of N95 masks available in the market are 13.9 and 21.8 respectively, while the average value of general planar surgical masks is 3.10 only, equivalent to the air leakage rate of 32.3% (i.e., the tightness is 67.7%), meaning that the bacterial filtration efficiency (BFE) is 67.7% only. Normally when the standard test for N95 is applied to surgical masks with BFE of 99%, meaning that 85 L is used instead of 32 L for the wind speed test, and the efficiency of filtering haze (PM2.5) is approximately 60% only; and if the air leakage rate is taken into consideration, the overall protection effect is approximately 40.6%. With the progress of production technology in recent years, the salt mist filtration efficiency of N95 dust masks is able to reach more than 99%; however, excellent masks still require to be equipped with the characteristics of proper tightness and low pressure difference. Nevertheless, the pressure difference (respiration resistance) of conventional N95 series of masks is relatively high such that they are not suitable for long-term wear, and such masks are particularly not suitable to the use by three groups of children, pregnant women and people with lung illnesses. As a result, even if the condition of haze is severe, they are still not suitable for wearing.

Furthermore, in recent years, various bacterial viruses and influenza have continuously attacked humans in the living environment, such as severe acute respiratory syndrome (SARS), avian influenza (H7N9), swine influenza (H1N1), etc., are severe hazards to human health, which also indicates that high-quality masks, and especially masks with excellent tightness and low pressure difference, are extremely important to the protection of human health.

As shown in FIG. 23, the patent document of the patent publication number TW201526945A discloses a mask A3 comprising a mask main body A10, and ear hook portions A12 formed at the two ends of the mask main body A10 in the lateral direction, as well as a plurality of fold marks A14 formed thereon. The plurality of fold marks A14 are secured by fused portions A22 formed via heat sealing. The fused portions A22 are located at the two sides of the mask main body A10 in the lateral direction and are arranged to be equally spaced apart from each other on the mask main body A10 in the longitudinal direction in order to form a linear shape. Furthermore, spacing between adjacent fused portions A22 is 3 mm (millimeter) and above. The two ends of the mask main body A10 in the lateral direction are covered by the side straps A30, and the ear hook portions A12 are installed on the aforementioned side straps A30. The two ends of the aforementioned mask main body A10 contacting with the sides of the face of the wearer in the lateral direction are formed of side area sections A32 covering the gap between the aforementioned face and the aforementioned mask main body A10. The side area sections A32 are formed by sandwiching one end of the wide-strap shaped side insulation strap A31 between the mask main body A10 and the side strap A30 in order to allow the side portion of the mask main body A10 to attach to the face properly and tightly, thereby preventing any gap formed between the mask main body A10 and the face of the wearer in order to prevent micro-particles from intruding into the mask.

In the aforementioned published patent, for the formation of the mask side area sections A32, the upper and lower ends of the side insulation strap 31 are fused to the first mesh seal A17 and the second mesh seal A24 first and then secured to the upper and lower sides of the mask main body A10/Next, the side strap A30 is used to cover one side of the side insulation strap A31 and the mask main body A10, which is then subsequently fused for completion. Consequently, the formation of the mask involves numerous steps and the manufacturing process is complicated. Moreover, the method of covering the side tape A30 onto the side insulation strap A31 and the mask main body A10 side adopted can also cause waste of the mask raw materials and increase the production cost.

BRIEF SUMMARY OF THE INVENTION

Regarding the aforementioned drawbacks, an objective of the present invention is to provide a novel airtight protective mask, utilizing an airtight sheet to cover one side of a mask body and fixedly attached to an outer layer and an inner layer in order to achieve a single-pass formation. As a result, the manufacturing process and structure of the airtight protective mask of the present invention are simple and its manufacturing cost is low.

Another objective of the present invention is to provide an airtight protective mask, using upper and lower fixation areas in an L shape for the fusion of the lanyards. During the fusion of the lanyards at the two ends, it is able to prevent the problem of the entire rear section of the lanyards being fused completely.

To achieve the aforementioned objectives, the present invention adopts the following technical solution: a novel airtight protective mask, characterized in that, comprising: a mask body sequentially having at least an outer layer, a middle layer and an inner layer; at least two airtight sheets fixedly attached to two sides of the mask body respectively; each one of the aright sheets comprising a fixation portion and a sealing portion extending from the fixation portion; the fixation portion configured to cover one side of the mask body and fixedly attached to the outer layer and the inner layer; the sealing portion arranged corresponding to a direction of the inner layer; two fixed attachment area sets, and each one of the fixed attachment area sets connected to the airtight sheets and the mask body; the fixed attachment area set comprising an upper fixation area and a lower fixation area; the upper and lower fixation areas fused to the mask body corresponding to two upper and lower ends of the sealing portion respectively; and a lanyard set, comprising two lanyards; the two lanyards connected to the two sides of the mask body respectively.

Furthermore, the airtight sheet is a single-layer structure or a multi-layer structure.

Furthermore, a fold cross section of the mask body is of an Ω shape or a zigzag shape.

Furthermore, the lanyard set is positioned on the outer layer or the inner layer and is arranged to face toward an inner side direction of the mask body.

Furthermore, the airtight protective mask further comprises an upper airtight sheet fixedly attached to an upper side of the mask body.

Furthermore, the airtight protective mask further comprises a lower airtight sheet fixedly attached to a lower side of the mask body.

Furthermore, the mask body is formed of two longitudinal folds.

Furthermore, the airtight protective mask further comprises an exhalation valve installed on the mask body.

Furthermore, the airtight protective mask further comprises an embedded nose pad arranged on a top portion of the mask body and between the inner layer and the outer layer.

With the adoption of the aforementioned technical solution, the present invention is able to achieve the following advantages: 1. The perimeter of the mask is able to fit to the face properly, and the two left and right sides as well as the bottom edge of the mask are able to attach to the face tightly. The contact surface is evenly distributed around the mouth and nose, thereby reducing any gap and preventing dust and particles from infiltrating through the gap. Consequently, the mask tightness is significantly increased, it is also able to achieve greater safety and comfort of the wearing of the mask. 2. The upper anti-fog airtight patch has an increased area to effectively block uprising fog, thereby preventing lenses above the mask from fogging. 3. The embedded nose bridge press strip is close to the nose bridge in order to effectively prevent dust and particles from infiltrating through the gap of the nose bridge. 4. Soft ear lanyards are provided to achieve comfortable wearing on the ears, such that the ears would not feel pain or discomfort after a long period of wearing of the mask. 5. The double-fold Ω three-dimensional structure is able to keep the mask at a distance from the lip such that the wearer would not feel any obstruction during breathing, and a comfortable mouth and nose spaces can be maintained while reducing the feeling of stuffiness and discomfort. 6. The mask has a special diamond shaped three-dimensional structure, and it is comfortable and appealing for wearing. During the wearing of the mask, the mask is not attached to the mouth and nose of the wearer, such that the wearer is able to breathe smoothly and to talk naturally without having any lip print on the mask, and perfect facial appearance can be maintained. 7. Medical grade filter material is used, and the mask body has 0.1 μm submicron particle filtration efficiency (Particulate Filtration Efficiency, PFE)≥99.9%, and bacterial filtration efficiency (Bacterial Filtration Efficiency, BFE)≥99.9%, complying with the standard for medical grade masks. 8. The filtering efficiency of the airtight sheet can reach above 95%, such that it is able to effectively block more than 95% of particles of size less than 0.1 μm (i.e., unit: micrometer) suspended in the air. It is also applicable to N95 grade anti-haze masks. Furthermore, depending on different filter materials of the mask, the airtight sheet used can also comply with the American standards for N95/N99/N100 series of dust masks, the EU standards for FFP1/FFP2/FFP3 series of masks or other specifications and standards of equivalent grade. 9. The mask is able to effectively prevent pollen, high-density dust, sand, smog and haze pollution and other harmful substances from inhaling by human bodies. In addition, the mask is able to effectively block PM 2.5 and achieve the isolation effect of isolating 99.9% of germs and air particles in the air. The mask can also be used as a protective means for cold, sneezing, flu and pollen, etc. Moreover, the mask is the first choice for smog and haze.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a novel airtight protective mask according to the first embodiment of the present invention;

FIG. 2 is a rear view of a novel airtight protective mask according to the first embodiment of the present invention;

FIG. 3 is a cross sectional view taken along A-A in FIG. 2;

FIG. 4 is a cross sectional view taken along B-B in FIG. 2;

FIG. 5 is a schematic view showing a wearer wearing a novel airtight protective mask according to the first embodiment of the present invention;

FIG. 6 is a schematic view showing the structure of a novel airtight protective mask according to the second embodiment of the present invention;

FIG. 7 is a schematic view showing the structure of a novel airtight protective mask according to the third embodiment of the present invention;

FIG. 8 is a schematic view showing the structure of a novel airtight protective mask according to the fourth embodiment of the present invention;

FIG. 9 is a front view of a novel airtight protective mask according to the fifth embodiment of the present invention;

FIG. 10 is a rear view of a novel airtight protective mask according to the fifth embodiment of the present invention;

FIG. 11 is a cross sectional view taken along C-C in FIG. 10;

FIG. 12 is a schematic view showing the structure of a novel airtight protective mask according to the sixth embodiment of the present invention;

FIG. 13 is a schematic view showing the structure of a novel airtight protective mask according to the seventh embodiment of the present invention;

FIG. 14 is a cross sectional view taken along D-D in FIG. 13;

FIG. 15 is a schematic view showing the structure of a novel airtight protective mask according to the eighth embodiment of the present invention;

FIG. 16 is a schematic view showing the structure of a novel airtight protective mask according to the ninth embodiment of the present invention;

FIG. 17 is a schematic view showing the structure of a novel airtight protective mask according to the tenth embodiment of the present invention;

FIG. 18 is a schematic view showing the structure of a novel airtight protective mask according to the eleventh embodiment of the present invention;

FIG. 19 is a cross sectional view taken along E-E in FIG. 18;

FIG. 20 is a schematic view showing the structure of a novel airtight protective mask according to the twelfth embodiment of the present invention;

FIG. 21 is a schematic view showing the structure of a novel airtight protective mask according to the thirteenth embodiment of the present invention;

FIG. 22 is a schematic view showing the structure of a novel airtight protective mask according to the fourteenth embodiment of the present invention; and

FIG. 23 is a perspective view of a mask of a known art.

In the drawings: 10—mask body; 11—outer layer; 13—middle layer; 15—inner layer; 16—horizontal fold; 17—longitudinal fold; 19—nose bridge piece; 20—airtight sheet; 21—fixation portion; 23—sealing portion; 30—fixed attachment area set; 31—upper fixation area; 33—lower fixation area; 40—lanyard set; 41—lanyard; 43—fastening strap; 50—upper airtight sheet; 60—lower airtight sheet; 70—exhalation valve; 80—embedded nose pad; 81—nose bridge strip; 811—iron wire; 812—plastic member; 83—elastic member.

In FIG. 23: In the known art, A3—mask; A10—mask main body; A12—ear hook portion; A14—fold marks; A22—fused portion; A30—side strap; A32—side area section; A31—side insulation strap; A17—first mesh seal, A24—second mesh seal.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is further described below in conjunction with specific embodiments. It can be understood that the embodiments are provided to illustrate the present invention such that they shall not be treated as limitations to the scope of the present invention. In addition, it can be understood that after reading the disclosure of the present invention, person skilled in the art in the field of the present invention may make any changes or modifications to the present invention; however, all equivalent changes and modifications shall be considered to fall within the scope defined by the claims of the present application.

As shown in FIG. 1 to FIG. 4, according to a first embodiment of the present invention, the present invention provides a novel airtight protective mask, comprising a mask body 10, an airtight sheet 20, a fixed attachment area set 30 and a lanyard set 40, as described in the following:

The mask body 10 is sequentially formed of a plurality of horizontal folds 16, and its internal includes at least an outer layer 11, a middle layer 13 and an inner layer 15. The outer layer 11 can be a water-repellent layer, such as a water-repellent nonwoven fabric (or a nonwoven fabric equipped with water-repellent function), capable of preventing infiltration of moisture and liquid. The middle layer 13 can be a filter layer, such as an electrostatic high-density meltblown nonwoven fabric (or electrostatic high-density meltblown nonwoven fabric) capable of blocking haze, virus and bacteria. The inner layer 15 can be a hydrophilic layer, such as hydrophilic ultra-fine composite fiber nonwoven (or hydrophilic ultra-fine composite fiber nonwoven fibric) that is soft and comfortable and is capable of absorbing moisture effectively. The horizontal folds 16 of the mask body 10 has a cross sectional shape of an Ω shape (as shown in FIG. 4). The double-fold Ω three-dimensional structure is able to maintain a certain distance between the mask and the lip, such the wearer would not have any obstruction feeling during breathing, and a comfortable mouse and nose space is maintained in order to reduce any stuffiness and discomfort.

The at least two airtight sheets 20 are fixedly attached to the two sides of the mask body 10 respectively. Each one of the airtight sheets 20 comprises a fixation portion 21 and a sealing portion 23 extending from the fixation portion 21 (as shown in FIG. 3). The fixation portion 21 covers one side of the mask body 10 and is fixedly attached to the outer layer 11 and the inner layer 15. The sealing portion 23 is arranged corresponding to the direction of the inner layer 15. In addition, each one of the airtight sheets 20 is a separable or composite nonwoven fabric with a two-layer structure, which is composed of two layers of spunbond and meltblown nonwoven fabric (or non-woven fabric) (Spunbond+Meltblown Nonwovens, SM). It is a spunbonded and meltblown composite products, capable of filtering out dust, particles and dirty air, etc. entering from the two sides of the mask.

For the two fixed attachment area sets 30, each one of the fixed attachment area sets 30 is connected to the airtight sheets 20 and the mask body 10. The fixed attachment area set 30 comprises an upper fixation area 31 and a lower fixation area 33. The upper fixation area 31 and the lower fixation area 33 are fused to the mask body 10 corresponding to two upper and lower ends of the sealing portion 23 respectively.

The lanyard set 40 comprises two lanyards 41 (such as ear straps), which can be ear-wearing type and fixed to the two left and right sides of the mask body 10 respectively. One end of the lanyards 41 is fixedly attached to the upper end of the mask body 10 and another end is fixedly attached to the lower end thereof. The lanyards 41 can be ear straps, fastening straps or head straps; however, the present invention is not limited to such types of straps only.

When a user wears the mask of the present invention, as shown in FIG. 5, the user holds the mask with the hands first, and the fold portion is expanded to form a three-dimensional space. The nose bridge piece 19 faces outward, and the lanyards are worn on the ears, allowing the mask to cover the mouth, nose and chin completely. The user then uses fingers to press the nose bridge piece 19, allowing the mask to fit tightly onto the nose and cheeks. In addition, the sealing portions 23 of the airtight sheets 20 can be expanded to fit closely to the face in order to reduce any gaps and to prevent dust and particles from entering the gaps. As a result, the mask tightness can be significantly increase and the wearing of the mask is safer and more comfortable.

Furthermore, the airtight sheets 20 cover one side of the mask body and are fixedly attached to the outer layer 11 and the inner layer 15 to achieve single-pass formation; therefore, the manufacturing process and structure of the mask are simple, and the production cost thereof is low.

As shown in FIG. 6, according to a second embodiment, a preferred embodiment of the present invention, the difference between the second embodiment and the aforementioned embodiment relies in that the airtight protective mask may further comprise an upper airtight sheet 50, or an anti-fog airtight patch, fixedly attached to the upper side of the mask body 10. Accordingly, as the area is increased, it is able to effectively block the uprising fog and prevent lenses from fogging. In addition, this embodiment is also able to achieve the same functions and technical effects described above.

As shown in FIG. 7, according to a third embodiment, a preferred embodiment of the present invention, the difference between the third embodiment and the aforementioned all of embodiments relies in that the airtight protective mask may further comprise a lower airtight sheet 60 fixedly attached to the lower side of the mask body 10. Accordingly, it is able to effectively fill the gap between the chin and the mask, thereby allowing the mask to fit to the shape of the face more completely and tightly.

As shown in FIG. 8, according to a fourth embodiment, a preferred embodiment of the present invention, the difference between the fourth embodiment and the aforementioned all of embodiments relies in that the airtight protective mask may further comprise an upper airtight sheet 50 and a lower airtight sheet 60 fixedly attached to the two upper and lower sides of the mask body 10 respectively, thereby achieving the function and technical effect of the aforementioned embodiments as shown in FIG. 6 and FIG. 7.

As shown in FIG. 9 to FIG. 11, according to a fifth embodiment, a preferred embodiment of the present invention, the difference between the fifth embodiment and the aforementioned all of embodiments relies in that the mask body 10 is formed of two longitudinal folds 17 (as shown in FIG. 11). Accordingly, when the mask body 10 is expanded, it is able to form a special diamond three-dimensional structure, providing comfortable and appealing wearing of the mask. In addition, during the wearing of the mask, the mask can be prevented from attaching to the mouth and nose, thereby allowing smooth breathing and natural talking behaviors without any lip prints, such that a perfect facial appearance can be maintained.

As shown in FIG. 12, according to a sixth embodiment, a preferred embodiment of the present invention, the difference between the sixth embodiment and the aforementioned all of embodiments relies in that the airtight protective mask further comprises an exhalation valve 70 installed on the mask body 10. Accordingly, during the breathing of the wearer, the user would not feel any obstruction, and comfortable mouth and nose space can be maintained, thereby reducing the feelings of stuffiness and discomfort.

As shown in FIG. 13 to FIG. 14, according to a seventh embodiment, a preferred embodiment of the present invention, the difference between the seventh embodiment and the aforementioned all of embodiments relies in that the airtight protective mask further comprises an embedded nose pad 80 or a nose bridge press strip structure, embedded at the top portion of the mask body 10 (as shown in FIG. 14). The embedded nose pad 80 comprises a nose bridge strip 81 and an elastic member 83. The nose bridge strip 81 is formed by a plastic member 812 and an iron wire 811 covered thereby. The elastic member 83 can be, such as, a foam. Accordingly, the embedded nose pad 80 or nose bridge strip structure is able to attach closely to the nose bridge, thereby effectively prevent dust and particles from infiltrating through the nose bridge gap.

As shown in FIG. 15, according to an eight embodiment, a preferred embodiment of the present invention, the difference between the eighth embodiment and the aforementioned all of embodiments relies in that the airtight sheet 20 is a separable or composite nonwoven fabric of a three-layer or four-layer structure, and it can be a nonwoven (or non-woven) composed of three layers of sheets of Spunbond+Meltblown+Spunbond Nonwoven (SMS) or four layers of sheets of Spunbond+Meltblown+Meltblown+Spunbond Nonwoven (SMMS) in order to form a composite product of spunbond and meltblown, thereby filtering out dust, particles, and dirty air that may enter from the sides of the mask. In addition, the airtight sheet 20 can also use a five-layer structure that can be the SMMS plus an additional antibacterial layer.

As shown in FIG. 16, according to a ninth embodiment, a preferred embodiment of the present invention, the difference between the ninth embodiment and the aforementioned all of embodiments relies in that the lanyard set 40 is positioned on the outer layer 11 and is arranged to face toward the inner side direction of the mask body 10 (forming inner ear straps), such that the convenience of the mask packaging can be increased. In addition, the upper and lower fixation areas 31, 33 in an L shape are used for the fusion of the lanyards 41, characterized in that when the two ends of the lanyards 41 are fused, problem of the entire rear end of the lanyards 41 being fused completely can be prevented.

As shown in FIG. 17, according to a tenth embodiment, a preferred embodiment of the present invention, the difference between the tenth embodiment and the aforementioned all of embodiments relies in that the lanyard set 40 is positioned on the inner layer 15 and is arranged to face toward the inner side direction of the mask body 10 (forming inner ear straps), such that the convenience of the mask packaging is increased.

As shown in FIG. 18 and FIG. 19, according to an eleventh embodiment, a preferred embodiment of the present invention, the difference between the eleventh embodiment and the aforementioned all of embodiments relies in that the cross section of the horizontal folds 16 of the mask body 10 is of a zigzag shape (as shown in FIG. 19), and it is applicable to a mask adopting the conventional folding method.

As shown in FIG. 20, according to a twelfth embodiment, a preferred embodiment of the present invention, the difference between the twelfth embodiment and the aforementioned all of embodiments relies in that the airtight sheet 20 is a nonwoven of a single-layer structure, and it can be Spunbond Nonwovens or Meltblown Nonwovens such that it is able to filter out dust, particles and dirty air, etc. from entering the two sides of the mask.

As shown in FIG. 21, according to a thirteenth embodiment, a preferred embodiment of the present invention, the difference between the thirteenth embodiment and the aforementioned all of embodiments relies in that the lanyard set 40 comprises at least two fastening straps 43, and each fastening straps 43 are fixedly attached along the left side and right side of the mask body 10 respectively. In addition to that the two ends extend out of the mask body 10, the length of the fastening strap 43 is preferably between 40 cm and 95 cm. During the use of the mask, fastening strap 43 can be fastened to the head portion for securement.

As shown in FIG. 22, according to a fourteenth embodiment, a preferred embodiment of the present invention, the difference between the fourteenth embodiment and the aforementioned all of embodiments relies in that the lanyard set 40 comprises at least two fastening straps 43, and each fastening strap 43 is fixedly attached to the upper side edge and the lower side edge of the mask body 10 respectively. In addition to that the two ends of the fastening strap extend out of the mask body 10, the length of the fastening strap 43 is preferably between 40 cm and 95 cm. During the use of the mask, fastening strap 43 can be fastened to the head portion for securement.

It shall be noted that the airtight sheet 20 may also be provided with an activated carbon layer, capable of absorbing ozone and organic odors. Alternatively, it may use an air impermeable material or film, etc., in order to block dust, particles and dirty air from entering the sides of the mask.

The mask of the present invention is able to effectively prevent harmful substances of pollen, high-density dust, sand, smog and haze pollution, etc. from being inhaled by human bodies; therefore, it is able to effectively filter out PM 2.5 and is the priority choice necessary for protection against smog and haze weather. Furthermore, the mask of the present invention is also suitable for colds, sneezing, flu, pollen and other means of protection, as well as means for preventing infections in places such as offices, public transit of mass rapid transit (MRT) and buses, or it may also be used as a means of protection for hospitals.

In view of the above, in comparison with the known art, the present invention has the following characteristics: Since the airtight sheets 20 cover one side of the mask body 10 and are fixedly attached to the outer layer 11 and the inner layer 15 in order to achieve single-pass formation, consequently, the manufacturing process and structure of the mask are simple, and its production cost is low.

In addition, the present invention also includes other features: The two left and right sides, bottom edge and upper edge of the mask are able to fit to the face closely and tightly such that the tightness of the mask is significantly improved. The double-fold Ω three-dimensional structure is able to maintain a certain distance between the mask and the mouth. Accordingly, during breathing, the wearer would not have any feeling of obstruction, and a comfortable mouth and nose space can be maintained, thereby reducing any feeling of stuffiness and discomfort. Furthermore, the soft ear lanyards provide comfortable wearing at the ears, and the mask can be worn for a long time without feeling any ear pain or discomfort.

The above describes preferred embodiments of the present invention only and such embodiments shall not be used to limit the scope of the present invention. The structure, dimension, arrangement location and shape of all parts can be changed and modified. However, all improvements and equivalent transformations of any parts of the present invention based on the principle of the present invention shall be considered to be within the scope of protection of the present invention.

NOVEL AIRTIGHT PROTECTIVE MASK

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