ES2266307T3 - FACIAL MASK WITHOUT HOLDING STRIPS. - Google Patents

Abstract

The present invention relates to face masks to control and improve the quality of inhaled air. Claimed and described is a respiratory face mask comprising a flange and a filter layer, the flange having an inner periphery and an outer periphery and a first and a second width measured perpendicular to the inner periphery between the inner periphery and the outer periphery, characterised in that the first width is greater than the second width. Preferably, such face masks are strapless and rely on a hydrogel adhesive for attachment and sealing. Further claimed and described is an improved cover layer for an adhesive of such a face mask. <IMAGE>

Description

Facial mask without braces.

Technical sector to which the invention belongs

The present invention relates to masks facials to control and improve the quality of inhaled air. Be claims and describes a respiratory facial mask that it comprises a crown-shaped flange and a filter layer, said crown-shaped flange having an internal periphery and an outer periphery as well as a first and second widths measured perpendicular to the inner periphery, between the inner periphery and outer periphery, characterized in that The first width is greater than the second width. Preferably, said facial masks lack strips of clamping and rely on a hydrogel adhesive for coupling and sealing. In addition, a layer of enhanced coating for an adhesive of said mask facial.

Background of the invention

A series of masks and are on the market, including masks Reusable and single-use facial masks for medical use, typically by surgeons, masks facials for professional use in which the air inhaled in the work environment requires it, and facial masks to private use, for example, for propagation prevention of infections, which are widely used in countries Asians

The prior art, referring to masks facial, includes the following documents:

US 4,966,140, issued October 30, 1999, which unveils a face mask for protection of the surgeon who performs the operation. The face mask substantially comprises vertical fixing strips and a strip sealing formed along its marginal part higher.

US 5,735,270, issued April 7, 1998, which unveils a folding, single-use face mask, comprising a generally rectangular sheet of material of filter, a sealing strip of a spongy material and a mask fastening device attached to the corners superior.

US 5,724,964, issued March 10, 1998, which reveals single-use, fixed face masks by a knitted band, to be held on the head of the user, which uses several elements of material from sealing of the type of a joint, such as an element of plastic sheets and / or hydrogels or other types of materials deformable, such as open cell spongy materials and closed cells. It is interesting to note that in this invention no types of adhesive hydrogels are provided.

JP 1-248.948, presented at 11 March 1997, unveils a face mask intended for cover the nose and mouth, which comprises an adhesive material in the periphery of the face mask.

WQ 00/07636, filed on July 30, 1999, unveils new particularly suitable adhesive hydrogels for single-use absorbent articles, but also usable for respiratory facial masks.

US 4,240,420, granted on December 23, 1980, and its continuation in part US 4,354,4889, granted on 19 October 1982, unveil filter masks comprising separate filter elements for the nose and mouth of the Username.

The prior art, in the general field of adhesives for fixing to the skin, it is especially developed in the field of articles such as auxiliary bands, patches and bandages.

In order to achieve the desired level of adhesion of said bandages, the elements of the prior art typically disclose the use of certain adhesives which have high cohesive forces, such as adhesive based in rubber and acrylics. These adhesives are then applied in shape of thick layers to maximize adhesive strength, whereby the bandage is fixed to the user's skin.

US 4,699,146 discloses adhesives sensitive to the pressure in hydrophilic elastomers, suitable for their use with ostomy devices, bandages, pads for ulcers, sanitary mats, diapers and mats for athletes. The adhesive comprises at least one crosslinked organic polymer by radiation and an adhesive plasticizer.

GB 2115431 discloses bandage adhesives, wound or burn gauze, EKG adhesives, mats sanitary, diapers and ulcer pads. The adhesive comprises an organic polymer crosslinked by irradiation, such as polyvinylpyrrolidine and an adhesive plasticizer.

However, for satisfactory use with a device such as a respiratory facial mask, which It can be carried for long periods of time, it is important that the adhesive has a skin compatible composition and that Do not be harsh or aggressive with respect to the skin or cause skin irritation or inflammation. It is also preferable that the Adhesive suits the user's skin in a way that get maximum skin surface contact between the Adhesive and skin. In addition, it is also desirable to disclose a adhesive such that the respiratory facial mask can be easily removed from the user, without the user experiencing any Unacceptable pain and no residue. This is particularly important in circumstances in which the device is removed and a new application is required once or even a series of times, for example, to allow better communication, to eat or others, and to ensure the application of said Sensitive skin devices, for example, in an old user advanced However, on the other hand, the desired level of adhesion, apart from being painless, must, of course, be maintained during said multiple applications of the device.

The problem of getting the level of adhesion desired is further increased in wet skin conditions. In some cases, before the placement of the device, the skin is cleaned and as a result it is usually wet. In addition, sweat moisture can develop while wearing the mask, for example, due to high ambient temperature or hard physical work. The commonly available adhesives, such as those containing hydrocolloid particles, not However, they often do not adhere strongly so immediate to the skin and it may be necessary to hold them in place until sufficient minimum adhesion occurs. Besides, the general adhesive capacity of said adhesives tends to be reduced significantly on moist skin surfaces because of its nature, so that the device will remain, so typical, fixed to the skin during use if any pressure on the device, for example, movements facial

Another problem especially prevalent in the Respiratory face mask utilization is the ability of the adhesive to adhere to greasy skin surfaces or oily The levels and types of fat and tallow naturally present in the skin, they vary from one person to another. In addition, the Adhesive must be reliably glued to skin with hair population and should allow its painless withdrawal from it.

For example, the document WO-A-97/24149 (3M) describes a polar pressure sensitive adhesive, lipophilic, which is said to it has an improved adhesion to greasy skin, including the adhesive a hydrophilic polymer matrix, a plasticizer organic polar and at least 9% by weight of a surfactant that it has an HLB (hydrophilic lipophilic balance) value of 10 to 17. It generally indicates that the hydrophilic polymer matrix is You can select from a wide range of polymers, including homopolymers and copolymers, for example, methacrylic acid and salts thereof, acrylamide, N-vinyl pyrrolidone and acid sulfonic acrylamidopropane and salts thereof. The adhesive is prepared by polymerization in a homogeneous aqueous mixture.

Taking into account the prior art that has been mentioned, there is a need to publicize a mask Enhanced respiratory facial, which meets the following objectives:

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The Mask is comfortable and safe in use.

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The mask is economical to manufacture, so that it can serve as single use item, however, can be reusable alternatively many times.

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The mask allows facial movement, namely at least open in certain measure the mouth, talk, cough and the like, keeping a reliable closure on the face.

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The mask can adopt a single dimension to fit a Wide variety of consumers.

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The mask works well on moist, greasy skin and, in particular, skin populated with hair.

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The mask reliably adheres to human skin throughout of prolonged periods of time.

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The Mask can be removed easily and conveniently.

Another objective of The present invention consists in disclosing a layer of coating for an adhesive layer, preferably formed by the face mask, said coating layer being easy to Peel off the adhesive and facilitate optimal application from the mask to the user's face.

It has been discovered, surprisingly, that the above objectives can be achieved by unveiling a face mask respiratory and a coating layer for an adhesive layer on the face mask, both with mechanical characteristics defined below, and preferably comprising a adhesive such as the one defined below.

Characteristics of the invention.

The present invention relates to facial masks for controlling and improving the quality of inspired air. A facial respiratory mask comprising a ring-shaped area and a filter layer is claimed and described, the ring-shaped area having an inner periphery and an outer periphery as well as a first and second widths measured perpendicular to the inner periphery between the inner periphery and the outer periphery, characterized in that the first width is greater than the second width. Preferably, said facial masks do not have fastening strips and are based on a hydrogel adhesive for fixing and sealing. An improved coating layer for an adhesive of said mask is further claimed and described.
facial.

Brief description of the drawings

The present invention will be better understood in relationship with the attached drawings, in which:

Figure 1 is a plan view of the side directed towards the user, of a preferred embodiment of the present invention

Figure 1a is a plan view of the face addressed to the user of a preferred embodiment of the present invention, the figure also showing the axis (A) defining sectors of the annular edge zone.

Figure 2 is a side view of it preferred embodiment of the present invention.

Figure 3 is a plan view of the face addressed to the user, of a preferred embodiment of a layer of adhesive coating equipped with protective papers removable

Detailed description of the invention Generalities

The present invention relates to masks facials to control and improve inspired air quality, that sometimes also receive the designation of masks respiratory facials, and in this description and for the purpose of greater simplicity, will be designated as face masks (10) or masks (10). Said masks (10) comprise at least an annular edge zone (20) and at least one control module of air, such as a filter layer (30), which can be integral or of type attached to the mask, being able to be separable pieces or not separable

A respiratory facial mask (10), of In accordance with the present invention, it can be designed to cover only the user's mouth, or only the nose of the user, but preferably it is designed to cover both organs respiratory, being able to be equipped with known fixing means in this technique, such as headbands or fastening strips in the head, which can run around the head and neck or that can run around the user's ears. They are highly preferable means, in accordance with the present invention, adhesive fixing means such as an adhesive layer arranged on the face directed towards the user of the element of annular shaped edge (20).

In addition, the respiratory facial mask (10) it can be equipped with sealing means known in the technique, for example, a spongy material. In most of preferred embodiments of the present invention, however, the layer of adhesive is arranged in the face mask (10), serving both as a means of fixation and as a means of tightness

A respiratory facial mask (10), at referred to below as a face mask protective (10), face mask (10) or mask (10), performed according to the present invention, it comprises as elements essential an annular shaped edge element (20) and a layer of filter (30). Preferred embodiments are shown in Figure 1 and in figure 2. These embodiments are, in principle, suitable as single-use masks for private users who want infection prevention

Annular Shape Edge Element

The annular shaped edge element (20) serves for sealing and, preferably, fixing the mask (10) to the user's face. Said edge element of annular shape is not intended to coat the respiratory organs (mouth and nose) of the user. If the mask is designed to cover the user's mouth and nose, the edge element of ring shape will typically be in contact with the nose, the Cheeks and chin of the user.

The annular shaped edge element has a inner periphery (22) surrounding the respiratory organs of the user, and an external periphery (24) that typically defines the external contour of the mask (10), see figures 1 and 2.

According to one aspect of the invention, the same It consists of the realization of a face mask (10) with a annular shaped edge element (20) greatly improved. By way of surprising, it has been discovered that by providing the face mask (10) of an annular shaped edge element (20) with width not uniform, significantly improves the sealing of the mask facial (10) with respect to the user's face.

The term "width" used in this description indicates the distance between the inner periphery (22) of the annular element (20) and the outer periphery (24) of said element annular (20), measured in the direction perpendicular to the periphery internal (22).

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More particularly, it has been found advantageous arranging parts of an annular element (20) with a remarkable width adjacent to the nasal bone and the center of the chin of the Username. In addition, it has been observed that it is advantageous to have part of said annular element (20), with reduced width in the areas located between the nose and cheeks, and around the corners from the user's mouth. Therefore, in one aspect of the present invention, a series of first widths can be measured in said annular element, whose width is greater than that of a series of second widths that can be measured in said annular element. Preferably, at least, one of said first widths is at least 10%, more preferably at least 20% and still  more preferably at least 30%, and even more preferably, at least 40%, but still more preferably 50%, and more preferably 80% higher than, at least one of said second widths.

Preferably, the face mask respiratory (10), performed in accordance with the present invention, it can be symmetric around a longitudinal axis, reflecting the symmetry between the left half and the right half of the face human The "center point", as used in this description, it will be the point of the longitudinal axis that cuts in two equal distances the distance from the outer periphery from the nasal part (26) to the outer periphery of the part of the Chin (29), as shown in Figure 1a.

Referring to the angle measured in the clockwise, between the longitudinal axis and the axis of reference (A) that crosses the center point, see figure 1a, preferably smaller areas are present in the following sectors: first, in a sector that extends from 20º to 80º, preferably from 30º to 70º, more preferably from 40º to 60º, and secondly, in a sector that it extends from 100º to 150º, preferably from 105º to 140º, more preferably from 110º to 130º, and in corresponding sectors symmetrical specular shape on the other side of the longitudinal axis. These areas are also designated as cheek areas (27) and zones (28) of the corners of the mouth, see figure 1.

In another important aspect, the parts of annular shaped edge element (20) having more width reduced, as described above, to which it is made reference in this description also as "parts narrow, "provide a hinge effect that allows facial movements Without wishing to be limited by any theory, it is believed that this hinge effect can be attributed to the greater flexibility of the annular element (20) in said zones more narrow, since less material is available therein. It is also believed that fewer folds are created in more areas narrow compared to wider areas when they are exercised efforts, for example, due to facial movements, about annular element (20). These folds are believed to be the origin of a poor sealing.

The face mask (10) of the present invention can have any shape, such as circular, oval, square, rectangular or triangular. Forms are preferred oval Typically, the shape of the face mask (10) comes essentially determined by the outer periphery (24) of the tab (20). If it is intended for an adult user, the periphery external (24) of the flange (20) must be shaped so that have a height along the longitudinal axis of 5 cm to 15 cm, preferably 8 cm to 12 cm, and having a width, measured at length of the transverse axis, through the central point, from 8 cm to 20 cm and preferably from 10 cm to 15 cm. Height is chosen preferably in a way that certain movements are possible facial and mouth opening. It has been discovered so surprising that the face mask (10), according to the present invention, allows even talk and cough, which provides comfort and safety.

The arrangement of the flange (20), in a design such as the one described above, has been discovered that surprisingly provides a very coupling improved and comfort for the use of the mask (10). In In particular, it has been found that, in combination with adhesives that will be released then you can get both improved sealing as reliable, unused fixation an excessively strong adhesive and, preferably, according to the present invention, without relying on other fixing means, such as tapes or header bands.

Without wishing to limit any theory, it believes that the arrangement of parts of smaller width allows the tab (20), which typically before use has flattened or two-dimensional shape, follow the three-dimensional contours of the human face more precisely and without them occurring folds, which are typically detrimental to the tightness of the mask (10).

In some embodiments of the present invention, an air control module (30) is arranged with more  of a tab (20). For example, tabs (20) can be arranged in a stacking arrangement, so that a tab used (20) can be separated by peeling and a new tab (20) comprising a new layer of adhesive. The stacking arrangement is maintained unitary by layers of adhesive arranged on the eyelashes (20) for user fixation In this embodiment, before use, only the outer flange (20) must be covered by a sheet removable (40).

Air control module

A very preferred air control module, of According to the present invention, it is a filter layer (30). The filter layer (30) may be constituted by a series of materials and different combinations thereof. Are included Within the preferred materials, non-woven materials, textile materials, for example, silk, linen or cotton, and paper soft cellulosic type. You can also use any material which is known in the art of absorbent articles, especially sanitary mats, panty liners and diapers, to be used as top sheet or back sheet of said absorbent articles. Known materials for use on a top sheet provide good liquid permeability and, therefore, also good air permeability, while which are also suitable for skin contact. The Known materials for use on a back sheet typically provide a lower degree of permeability to air, but the newly developed materials provide a high permeability to water vapor and air, so They may consider favorably for the present use. Due to the humidity of the expelled air, the materials that provide good water vapor permeability are highly preferred, to avoid the sensation of humidity during use of the face mask. Moreover, the layer of filter (30) should preferably filter a certain humidity of the air expelled, for example, traces of saliva or blood, to suppress the spread of infections.

In some preferred embodiment of the present invention, the mask (10) and, more preferably, the layer filter (30) will also comprise an absorption compound of odors, for example, activated carbon or zeolites.

The filter layer (30) formed by the mask facial (10), according to the present invention should be select, so that you have a certain degree of flexibility. The flexibility provides better adaptation to facial contour of the individual user, less tensions on the areas of adhesion during facial movement, and comfortable packaging of the device, and It must be selected with all this in mind.

However, the filter layer (30) formed by the face mask (10) must also be selected so that Have a certain degree of stiffness. Depending on the realization specific to the present invention, the stiffness of the flexible sheet prevents the blade from extending into the user's mouth (if open). The tongue contact with this sheet can be consider unpleasant by some users, for example, given that the taste of a non-woven material can be perceived as little nice.

The requirement of rigidity aside and the requirement of flexibility on the other side can be reconciled if a somewhat rigid material, or at least not inconsistent with a medium stretching, such as folds (32). A wide variety of models folding can be used to achieve stretching means. Preferably, the area of the filter layer (30) directly Adjacent to the user's mouth is free of folds (32). For the so, preferably, the folds are arranged slightly above the upper lip and below the lower lip of the user, being able to optionally arrange other folds in the nasal part of the user. In highly preferred embodiments of the present invention, two or four folds (32) are arranged, plus preferably, one or two folds, respectively, above the upper lip and below the user's lower lip. A preferred embodiment with four folds is as shown in figure 2. While the folds can be arranged so symmetrical, it is even more preferred to arrange them asymmetric to achieve greater stretching capacity in the area of the nose that in the mouth area.

In alternative embodiments of the present invention, the air control module (30) may comprise a more complex coating material, to control the air inhaled and / or expelled. In a preferred embodiment of the present invention, the air control module (30) comprises means to control, in particular, to enrich the air inhaled, for example, with oxygen, as used in the apparatus for artificial respiration in medical practice. In other preferred embodiment, the air control module (30) comprises means to analyze the expelled air. These means can be designed to analyze traces of alcohol consumed, as used for example in alcohol tests conducted by police forces, also considering using means to analyze the air expelled with respect to the metabolism of a person for broader medical goals.

In some embodiments of the present invention, the air control module (30) is fixed with detachability to the flange (20), so it can be replace the air control module (30). The module change (30) air control can be carried out when the mask (10) is not used, providing at least the advantage of the economic reuse of the tab (20) or, in others cases, can be carried out while using the mask (for example, to adapt to different filtering requirements in a work environment) without removing the tab (20) and reconnect it.

Preferred adhesives

In accordance with the present invention, the adhesive on the side of the face mask (10) corresponding to the User face can be applied in any way, symmetrical or asymmetric, for example, in the form of a dotted drawing or of lines. Preferably, the adhesive is disposed only on the tab (20) of the face mask (10), and the filtering layer (30) is free of adhesive.

The adhesive is arranged in one or several areas from the side corresponding to the face of the mask user respiratory tract (10), to which reference will be made below also as a "device", in the form of a layer that has a certain thickness or gauge C measured in millimeters (mm). Preferably, gauge C is constant for all areas (20) equipped with an adhesive coating, but gauge C It can also be variable.

The adhesive can be applied at least on part of the side corresponding to the user's face of these devices forming a layer with a thickness or gauge that is preferably constant, but which may alternatively vary on the surface interested in the application of the adhesive. He Adhesive can be applied to the side of the device directed towards the user's face by any means known in this technique, such as coating by a groove, spiral application or by application of drops, or by impression. Typically, the adhesive it is applied with a basis weight of 20 g / m2 up to 2500 g / m2, preferably from 500 g / m2 to 2000 g / m2, or more preferably 700 g / m2, at 1500 g / m2, depending on the intended final use.

The detailed analysis of the sequence of common situations that take place in the devices, in the moment of their withdrawal, has shown that Specific characteristics of the adhesive must be satisfied preferably to achieve performance goals desired, in particular, for a secure initial fixation, a secure fixation during use and removal without pain after of utilization The characteristics that have been considered in this context is the elastic module that describes the behavior elastic material and viscous module that describes the viscous behavior of the adhesive material.

The viscous behavior of the adhesive can be interpret that represents an indication of the ability of the adhesive and to adhere quickly safely to a determined surface. The elastic behavior can be interpreted as an indication of the "hardness" behavior of adhesive. Its value is also important for a good coupling initial. Its combination is believed to be an indicator of strength required at the time of decoupling. The relationship between The elastic and viscous modules are considered to be an indication what is the fraction of decoupling energy that is will dissipate inside the adhesive and what fraction is available to cause true decoupling.

In order to provide adhesives for a safe and prolonged initial coupling, as well as for a easy and painless decoupling, the relationship between the elastic module and the viscous module, as well as its behavior dynamic.

The adhesive has a viscous module in the temperature of 37ºC (100º Fahrenheit) of G'37, a viscous module at a temperature of 37ºC (100º Fahrenheit) of G''37, and a module viscous at the temperature of 25 ° C (77 ° Fahrenheit) of G''25.

The adhesive, according to the present invention, preferably satisfies the following conditions;

G'37 (1 rad / sec)

in the range of 500 Pa to 20,000 Pa, preferably 700 Pa to 15000 Pa, more preferably 1000 Pa a 10000 Pa.

G''37 (1 rad / sec)

in the 100 Pa range to 15000 Pa, preferably 100 Pa to 10000 Pa, more preferably 300 Pa a 5000 Pa.

and the proportion of G'37

(1 rad / sec) / G''37 (1 rad / sec) se It is between 1 and 30.

On condition that the conditions are met rheological mentioned above, the adhesives will satisfy also conditions such as sufficient cohesiveness (to prevent adhesive residues on the skin) that are important for use commercial of said adhesives and evident to the technicians in the matter. Adhesive compounds that meet the criteria Above can be used as adhesives for the device provided that they also meet the common requirements of safety for use in humans or in animal skin during use and, in general, after the removal of device.

Frequently, the criteria for hygienic appearance so that the adhesive compounds are transparent or white in your application.

It has been determined that the relationship that the ratio between thickness or gauge C, measured in millimeters (mm), of the layer in which the adhesive is disposed, typically, on, at least a part of the surface of the targeted device towards the user, and the viscous module G''25 at approximately 100 rad / sec of the adhesive, is relevant in order to provide an easy and painless removal from the user's skin of the applied adhesive, at least on a part of the surface of the device directed towards the user for fixing the device in the user's skin.

The adhesive of the present invention is arranged, therefore, preferably in the form of a layer with a thickness C, such that the viscous module G''25 (100 rad / sec) and the thickness C fully satisfy the following equation empirical:

G''25 \ leq [(7.00 \ + \ C) \ x \ 3000] \ Pa

and preferably also the next equation empirical:

G''25 \ leq [(5.50 \ + \ C) \ x \ 1700] \ Pa

While in a preferred embodiment of the present invention of the thickness C of the adhesive layer is constant, said adhesive layer may also have different thicknesses in different parts of the surface of the device directed towards the user when it is applied, provided it is satisfied, in in any case and anywhere, the aforementioned relationship between C and G''25.

The skin of the user to which they are applied in a manner typical these devices will vary considerably from one person to another. In particular, the type and amount of fat or tallow produced It can vary considerably from one person to another. However, the facial area, and particularly around the chin, is known to produce high levels of sebum and reproduce it with speed, even if a part is removed, for example, by cleaning of the corresponding areas of the skin. In addition, users of These devices can apply creams to the skin area that makes contact with adhesives, for example, creams moisturizers Therefore, it is important to have an adhesive that Adheres to greasy skin. Accordingly, this invention provides an adhesive that has an initial strength dry peel (PDI) and an initial peel strength in fat (PGI) determined by the test method described, in which the ratio of PDI to PGI is 1: 1 to 1.0: 0.2, preferably from 1: 1 to 1: 0.3. Typically, for use For devices, the initial dry peel strength is (PDI) from 0.1 N / cm to 7.0 N / cm, preferably from 0.1 N / cm to 5.0 N / cm, and more preferably from 0.5 N / cm to 3 N / cm. The value of the initial resistance of peeling with grease is preferably equal than the initial dry peel. However, typically achieves a lower level and is acceptable for levels of 0.1 N / cm at 5 N / cm, preferably 0.1 N / cm to 3 N / cm, more preferably from 0.1 N / cm to 2 N / cm. It is also preferable that skin adhesion greasy hold during a period of use such that the ratio between initial peel strength with grease (PGI) and resistance to final peeling with grease (PGF) ranges from 1: 1 to 1: 0.25 preferably from 1: 1 to 1: 0.5.

Due to the nature and environment in the that these devices are used, a characteristic such that the adhesive has an absorption capacity of water as defined in the test, which is indicated by, as minimum, 3% by weight of said adhesive (so that the adhesive is adheres directly on wet or damp skin). In particular, the proportion of the peel strength of the adhesive, determined in test methods, it should be more preferably maintained in a constant value, so that the proportion of resistance initial peeling (PDI) and final peeling resistance (PWF) is between 2: 1 to 1: 4, preferably from 2: 1.25 to 2: 4, plus preferably from 2.0: 1.5 to 2.0: 2.5. Typically, for these devices, initial peel strength for dry skin and, more preferably, also for moist skin, it should be 0: 1 N / cm a 0.0 N / cm, 0.1 N / cm at 5.0 N / cm, preferably 0.5 N / cm at 3.0 N / cm

In addition, it is preferable that the adhesive, in addition to maintain peel strength for a period of time even with the presence of water, also absorb less than 15%, preferably less than 10%, and more preferably less than 7% of Water. Although it is not desired to be bound by any theory, it is believed which, in order to obtain direct adhesion on wet skin and maintain constant adhesion behavior throughout a certain period of use, even when exposed to liquids in excess or high humidity, the ability of the adhesive to absorb Water has to be considered. In particular, it has been discovered that not only the absolute capacity of the adhesive has to be taken into account, but also the proportion of water absorption to effects of providing an adhesive that meets the parameters of behavior indicated above.

For example, hydrocolloid particles that contain adhesives known in the art, comprising a three-dimensional rubber matrix and colloidal absorbent particles scattered inside, they are only able to absorb limited amounts of water through the particles themselves colloidal and not of the matrix itself. Besides, the proportion to which water is absorbed is slow. Therefore these  adhesives of the previously known type do not adhere to wet surfaces

Moreover, hydrogel adhesives previously known are not only able to absorb large  quantities of water, but also at a fast speed. How As a result, said adhesives may be able to adhere to wet surfaces, however, due to the combination of a fast absorption speed and rapid water absorption in values Absolute, these adhesives lose their adhesive strength with rapidity in the presence of excess water or high humidity.

Accordingly, the adhesives of the present invention simultaneously have the ability to adhere directly to moist skin, having a minimum capacity of absolute water absorption in combination with a speed of absorption such that the peel strength remains within defined values throughout the period of use.

The adhesive is provided in the preferred manner, typically on the device surface directed towards the user, in the form of a layer that has a thickness or gauge C preferably constant. The layer may preferably be continuously or alternatively discontinuous, for example in the form of points, spirals or lines.

Although adhesives are used as pressure sensitive adhesives on human skin and tissues of the mucous, it will be understood that the adhesive compounds hardly could be considered typical pressure sensitive adhesives (to be indicated below PSA) based on the behavior most characteristic rheological that identifies these materials.

Actually, as technicians know in the matter, the characteristic that best distinguishes a PSA from others substances that can temporarily adhere to objects (for example, as water could do between two glass plates) it is the fact that its rheological parameters and, especially, the Elastic Module G 'varies significantly with the frequency of applied efforts. More particularly, G 'of PSA can increase in several orders of magnitude, while the frequency of applied stress varies from a typical frequency of attachment to a typical separation frequency, that is, 1 rad / sec to 100 rad / sec, as indicated below.

As a first consequence, it is inadmissible so both define materials intended for use as "adhesives" giving rheological parameter values, and in special of G ', at a fixed frequency value. This could be object of confusion because in the absence of other characteristics, such as surface chemistry, would include materials that do not They have practical value. Therefore, it is necessary that rheological characteristics based on considerations dynamic This is not only applicable to Elastic Module G 'but also to the viscous module G '' and, therefore, also for tan (d) = G '' / G '.

It is well known that typical PSAs have, not only a high variation of G 'according to the frequencies considered, but also that there is even greater variation of G '' that may be closer or higher than the value of G ', that is, tan (d) is similar or even greater than 1, in particular at frequencies that are typically separation.

Without wishing to be bound by any theory specific, this phenomenon can be interpreted with the meaning that a high fraction of the energy applied to the separation dissipates within the adhesive (therefore, it is not effective in producing separation) and through the interface of adhesive and skin while this fact causes macroscopically registering a very high level of force adhesive

As indicated above, the materials useful as adhesives, in accordance with this invention, they have rheological characteristics that are measured at a reference temperature of 37 ° C (such as usual temperature of the body of humans) and in a range of frequencies. It has been discovered that, in the application of a device with a adhesive, the adhesive contact forms at low frequency, while separation takes place at withdrawal speed Of the device. This speed is expressed as a frequency of 100 rad / sec, while the link formation low frequency Adhesive has been observed to be of the order of 1 rad / sec. For the therefore, the range of use, according to the present invention, is between 1 and 100 rad / sec.

In order to provide good conditions of union, that is, at an approximate frequency of 1 radian / second, the absolute values of the Elastic Mode should not be too many high, otherwise the adhesive is too hard and is not able to bond intimately or mold on the surface to which it You want it to adhere. It is important to have a low absolute value of G '', in order to have good cohesion while the material remain soft and able to adhere gently to the skin.

The proportion of G'37 (1 rad / sec) with respect to G''37 (1 rad / sec) is important to ensure that these two values They are balanced in adhesion to the skin.

Importantly, the proportion

\hskip0.3cm

-

\hskip0.3cm

G''37 (100 \ rad/seg)}{G'37 (1 \ rad/seg)

\hskip0.3cm

-

\hskip0.3cm

G''37 (1 \ rad/seg)}\ frac {G'37 (100 \ rad / sec)

 \ hskip0.3cm 

-

 \ hskip0.3cm 

G''37 (100 \ rad / sec)} {G'37 (1 \ rad / sec)

 \ hskip0.3cm 

-

 \ hskip0.3cm 

G''37 (1 \ rad / sec)}

must be large enough to ensure that the dynamic behavior of the elastic modules and viscous is maintained in a relationship that provides a secure adhesion and easy removal without pain.

Finally, technicians in the field They will also observe that the Transition Temperature to Vitreous state Tg of the adhesive compound, the specific heat capacity and the Specific thermal conductivity are useful parameters to define more completely the group of useful adhesives.

The following set of features is due preferably satisfy for the adhesive herein invention:

the proportion

\hskip0.3cm

-

\hskip0.3cm

G''37 (100 \ rad/seg)}{G'37 (1 \ rad/seg)

\hskip0.3cm

-

\hskip0.3cm

G''37 (1 \ rad/seg)}\ frac {G'37 (100 \ rad / sec)

 \ hskip0.3cm 

-

 \ hskip0.3cm 

G''37 (100 \ rad / sec)} {G'37 (1 \ rad / sec)

 \ hskip0.3cm 

-

 \ hskip0.3cm 

G''37 (1 \ rad / sec)}

is not less than 0.5, preferably from 0.7 to 3, and more preferably from 1 to 1.8.

The value of the G'37 / G''37 ratio at least for the previously indicated frequency range of 1 rad / sec up to 100 rad / sec should preferably not be less than 0.5, preferably from 0.7 to 10 and more preferably, from 1 to 7.

Rheological behavior can also be related to Transition Temperature values in Vítrio Tg state. For topical adhesives, in accordance with this invention, Tg should preferably be less than 0 ° C, more preferably less than -5 ° C, and still more preferably, less than -10 ° C.

In circumstances where adherence and sealing on skin endowed with hair is desirable, such as occurs frequently when the face mask is used by a male, particularly those who wear a beard, has to be considered the following, additionally, with respect to the optimal rheology of the adhesive:

As indicated above, the materials useful as adhesives, in accordance with this invention, they have rheological characteristics that are measured at a reference temperature 37 ° C (usual body temperature in human) and in a range of frequencies. It has been discovered that, in the application of articles with an adhesive, the adhesive contact remains constituted at low frequency, while the separation has place at the speed of withdrawal of the article. This speed is expressed as a frequency of 100 rad / sec, while the frequency  Low adhesive bond formation has been observed to be of order of 1 rad / sec. Therefore, the frequency range of use, in accordance with the present invention, is comprised between 1 and 100 rad / sec.

In order to provide good conditions of the union, that is, at an approximate frequency of 1 rad / sec, the absolute values of the elastic modules G 'must not be too much high, since otherwise the adhesive is too hard and cannot be intimately joined or molded with the surface to which It is expected to adhere. It is also important to have a value reduced absolute of G '', in order to have good cohesion, while the material remains soft and able to adhere gently to the skin.

In order to ensure the penetration of hair to through the hydrogel adhesive so that the adhesive is able to establish contact with the skin surface and join the same, and in such a way that the hair can be easily uncoupled of the hydrogel adhesive when removed without pain or without leaving waste, it has been discovered that an elastic module and the module viscous adhesive must be within certain absolute values, showing a minimum delta value.

The following set of features should Be satisfied by the adhesive of the present invention:

G'37 (1 rad / sec)

It is within the range from 100 Pa to 4000 Pa, preferably from 300 Pa to 2500 Pa, more preferably from 400 Pa to 1500 Pa.

G''37 (1 rad / sec)

It is within the range from 100 Pa to 5000 Pa, preferably from 200 Pa to 2000 Pa, more preferably from 300 Pa to 2000 Pa.

G'37 (1 rad / sec)

it is at least 50 Pa.

G''37 (1 rad / sec)

preferably a minimum of 150 Pa, more preferably, at least 200 Pa, more preferably at least 300 Pa.

In addition, in order to ensure adherence initial required with the skin, and preferably throughout the period of use, the adhesive has a resistance to peeled between 0.1 N / cm and 5 N / cm, preferably 0.2 N / cm at 3 N / cm, as determined according to the method described

The values of the elastic module, viscous module and peel strength can be selected from the ranges of values indicated above, depending on the final use planned.

The nature of the hair itself also affects its ability to penetrate the hydrogel adhesive, in particular thickness, length, density and wavy character of Hair are important. It has been discovered that the possibility that a certain type of hair is embedded inside the adhesive of hydrogel can be determined by the following equation based on hair of an area of 1 cm2.

W x C x G'25 (1 rad / sec) <24

in the that:

W

= weight (assuming constant specific gravity)

V

= volume

C

= ripple (proportion of stretched hair length and length of unstretched hair).

In order to provide adhesive compounds that meet the requirements of rheological characteristics and above physical properties of an adhesive, can be used pressure sensitive adhesives and substantially insoluble in water, which are medically appropriate, which they comprise a polymer that forms a three-dimensional matrix that It meets these characteristics.

In accordance with the present invention, the matrix three-dimensional referred to as gel comprises a essential component of a polymer that can be crosslinked physically or chemically. The multimeter can be natural or synthetic. The uncrosslinked polymer comprises repetitive units. or monomers derived from vinyl alcohols, vinyl ethers and its copolymers, carboxyvinyl monomer, vinyl ester monomers, carboxyvinyl esters monomers, vinyl amide monomers, vinyl hydroxy monomers, cationic vinyl monomers containing quaternary amines or groups, monomer of N-vinyl lactam, polyethylene oxides, polyvinyl pyrrolidone (PVP), polyurethanes, acrylics such as methyl acrylate, 2-hydroxyethyl methacrylate, methoxydiethoxyethyl methacrylate and hydroxydiethoxyethyl methacrylate, acrylamides and sulfonated polymers such as sulfonated acrylamide polymers, for example, 2 acrylamido methylpropane sulfonic acid (AMP) and acid Acrylic (3-sulfopropyl) ester (SPA), and mixtures of the same. Also acrylonitrile, methacrylamide, N, N-dimethylacrylamide (NNDMA), acrylic esters such as methyl, ethyl and butyl acrylates. Alternatively, the uncrosslinked polymer can be a homopolymer or copolymer of a polyvinyl ether, or a copolymer derived from the ester half of maleic ester. Similarly, any units of Compatible polymer monomers can be used as copolymers such as, for example, polyvinyl alcohol and acid polyacrylic or ethylene and vinyl acetate.

As another alternative, the polymers can be thermoplastic elastomers of block copolymers, such as ABA block copolymers such as styrene-olefin-styrene block copolymers or ethylene-propylene block copolymers. More preferably, these polymers include styrene / ethylene butylene / styrene (SEBS), styrene / isoprene / es-
tyrene (SIS), and styrene / ethylene-propylene / styrene (SEPS) in hydrogenated quality.

Especially preferred polymers are Acrylics, sulfonated polymers such as sulfonated polymers of acrylamide, vinyl alcohols, vinyl pyrrolidone, oxide polyethylene and mixtures thereof. The most preferred are nitrogen containing polymers.

In accordance with the present invention, the matrix three-dimensional adhesive also essentially comprises a plasticizer that is preferably a liquid at temperature ambient. This material is selected in such a way that the polymer can be solubilized or dispersed within the plasticizer For realizations in which they have to take After irradiation crosslinking, the plasticizer must also be compatible with irradiation crosslinking so that no inhibits the process of crosslinking by irradiation of the polymer. He Plasticizer can be hydrophilic or hydrophobic.

Suitable plasticizers include water, alcohols, polyhydric alcohols such as glycerol and sorbitol, and glycols and ether glycols such as mono or diesters of polyalkylene glycol, mono or polyalkylene glycol diesters, polyethylene glycols (typically at a molecular weight of 600 approximately), glycolate, glycerol, sorbitan esters, esters of citric and tartaric acid, amphoteric surfactants derived from imidazoline, lactams, amides, polyamides, ammonium compounds quaternaries, esters such as phthalates, adipates, stearates, palmitates, sebacatos, or myristates, and combinations thereof. Particularly preferred are polyhydric alcohols, polyethylene glycol (with a molecular weight that reaches 600 approximately), glycerol, sorbitol, water and mixtures of same.

Typically, the adhesive comprises a ratio of polymer to plasticizer by weight from 1: 100 to 100: 1, more preferably from 50: 1 to 1:50. However, the quantities and exact proportions of the polymer and plasticizer will depend, to a large extent, the exact nature of the polymer and the plasticizers used, and can be easily selected by The technician in the field. For example, a high polymer material molecular weight will require a greater amount of plasticizer than a low molecular weight polymer.

In addition, the adhesive may comprise in addition to Preferred mode, a polymer for lipid micellation, is that is, a polymer of the type called hyper-rolled ("hypercoiling"). This polymer works by micellizing and removing rolled grease bags from the interface gel-skin

The hyper-rolled polymer has the ability to more effectively solvate the surfactant micelles primary that establish contact with the hydrophobic contaminant of the skin, such as skin lipid or skin cream. The consequence of this functionality is that the adhesion work between the adhesive and the skin is progressively less affected by the presence of active tense or hydrophobic contaminant of the skin.

The hyper-rolled polymer comprises preferably any of the following components alone or in combination: poly (maleic acid styrene), poly (maleic acid butyl vinyl ether), poly (maleic acid propyl vinyl ether), poly (maleic acid ethyl vinyl ether) and poly (ethyl acrylic acid acrylate).

An especially preferred example is a copolymer that alternates styrene and maleic anhydride. As it explained below, the adhesive tries to provide a Biphasic structure in polymerization. These two phases are hydrophilic and hydrophobic. The hydrophobic phase can be provided by a hydrophobic monomer that is initially maintained as part of the homogeneous reaction mixture by reactive solvent bridge. Alternatively and / or additionally, the hydrophobic component is provided in the form of polymer that separates from the aqueous phase at the time of polymerization.

The exact amounts and proportions of hyper-rolled polymer will depend, to a large extent, on nature  of the components.

Under certain circumstances, the reaction mixture preferably comprises from 3% to 20%, and more preferably from 8% at 18% by weight of the reaction mixture, of a dispersion of stabilized polymer that is used to provide a system Stable phase separated. The polymer preferably comprises any of the following compounds alone or in combination: dioctyl maleate vinyl acetate copolymer or copolymer of ethylene vinyl acetate. It is preferable ethylene vinyl acetate copolymer, such as the marketed under the trade name DM137 of Harlow Chemicals

The adhesive also preferably comprises surfactants, such as nonionic, cationic surfactants, anionic, amphoteric and any mixtures thereof.

They are included as non-ionic surfactants, not suitable reagents, without any limitation to those indicate, those of the group consisting of condensation products of a long chain aliphatic alcohol, such as a fatty alcohol, which contains 8 to 20 carbon atoms, in a configuration of straight or branched chain, condensed with about 3 to 100 moles, preferably 5 to 40 moles and, more preferably, about 5 to 20 moles of ethylene oxide. Examples of such surfactants are non-ionic ethoxylated fatty alcohols Tergitol.TM. 15, S series of Union Carbide and surfactants Brij.TM. of ICI. Surfactants Tergitol.TM. 15 S, comprise polyethylene glycol ethers of secondary alcohols C.sub.11-C.sub.15. He Brij.TM 58 surfactant is polyoxyethylene (20) cetyl ether, and the Brij.TM.76 surfactant is polyoxyethylene (10) stearyl ether.

Other non-ionic, non-reactive surfactants suitable include, without limitation, selected from the group consisting of polyethylene condensates oxide of one mole of alkyl phenol, containing approximately 6 to 12 carbon atoms in a straight chain configuration or branched, having about 3 to 100 moles of oxide of ethylene. Examples of non-ionic surfactants are Igepal.TM. Rhone-Poulenc CO and CA series. Surfactants Igepal.TM.CO comprise nonylphenoxy poly (ethyloxy) ethanes. Igepal.TM.CA surfactants include octylphenoxy poly (ethyleneoxy) ethanes.

Another group of non-ionic surfactants, not Reagents that can be used include, but do not serve as limitation, those selected from the group consisting of copolymers block of ethylene oxide and propylene oxide, or butylene

Examples of such surfactants are non-ionic block copolymer Pluronic.TM series. and Tetronic.TM. of BASF surfactants. Pluronic.TM surfactants. understand block copolymers of ethylene oxide-propylene oxide. The Tetronic.TM surfactants. comprise oxide block copolymers of ethylene-propylene oxide. Suitable examples are Pluronic L68 and Tetronic 1307. Pluronic are particularly suitable examples L64 and Tetronic 1107.

Other non-ionic, non-reactive surfactants satisfactory include, without limitation, the selected from the group consisting of acid sorbitan esters fatty, polyoxyethylene sorbitan fatty acid esters and stearates of polyoxyethylene. Examples of such nonionic surfactants of fatty acid esters the surfactants Span.TM., Tween.TM., and Myrj.TM. of ICI. Span.TM. Surfactants include monoesters C.sub. 12-C.sub. 18 sorbitan. The surfactants of Tween.TM. include poly (ethylene oxide) C.sub. 12-C.sub. 18 sorbitan monoesters. Surfactants Myrj.TM. include poly (ethylene oxide) stearates.

Suitable anionic surfactants will include normally a hydrophobic fraction selected from the group that It consists of groups (approximately C.sub.6 to C.sub.20) alkyl, alkylaryl and alkenyl, and an anionic group selected from the group consisting of sulfate, sulphonate, phosphate, polyoxyethylene sulfate, polyoxyethylene sulfonate, polyoxyethylene sulfonate, polyoxyethylene phosphate and alkali metal salts, ammonium salts and aminotercial salts of said anionic groups.

They are included among the anionic surfactants that they can be used in the present invention, although this does not serves as a limitation, those selected from the group consisting of (approximately C.sub.6 to C.sub.20) alkyl or alkylaryl sulfates or sulfonates, such as sodium lauryl sulfate (available commercially as the company's Polystep.TM B-3 Stepan Co.) and dodecyl benzene sodium sulfonate (available commercially according to the Siponate.TM brand. DS-10 of Rhone-Poulenc); polyoxyethylene (approximately C.sub.6 to C.sub.20) alkyl or alkylphenol ether sulfates with the repeating ethylene oxide unit in the surfactant below of about 30 units, preferably below about 20 units, more preferably below about 15 units, such as Polystep.TM.B-1 commercially available from Stepan Co. and Alipal.TM.EP 110 and 115 of Rhone-Poulenc; (approximately C.sub.6 to C.sub.20) alkyl or alkylphenoxy poly (ethyleneoxy) ethyl monoesters and diesters of phosphoric acid and its salts, with the repeating ethylene oxide unit in the surfactant below of 30 units, preferably below 20 units, more preferably below about 15 units, such as Gafac.TM.RE-510 and Gafac.TM.RE-610 of GAF.

They are included among cationic surfactants useful according to the present invention, without this serving as limitation, those selected from the group consisting of salts quaternary ammonium, in which at least one weight group high molecular weight and two or three groups of lower molecular weight are linked with a common nitrogen atom to produce a cation and, in which the electric equilibrium anion is selected between the group consisting of a halide (bromide, chloride, etc.), acetate, nitrite, and short chain alcosulfates (methosulfate, etc.). The substituent or substituents of high molecular weight in the nitrogen are frequently (a) long chain alkyl groups, containing approximately 10 to 20 carbon atoms, and the low molecular weight substituents can be chain alkyl cuts from about 1 to 4 carbon atoms, such as methyl or ethyl, which may be substituted, such as hydroxy, in some cases. One or more of the substituents may include a aryl fraction or may be substituted by an aryl, such as benzyl or phenyl.

In a particularly preferred embodiment of the invention, the surfactant comprises at least one copolymer propylene oxide / ethylene oxide block, for example, such as the one supplied by BASF Plc with the Pluronic L64 brand. Mix The reaction ideally comprises 0.1% to 5% by weight of the reaction mixture of the surfactant.

The surfactant works by removing fat from the skin and forming the removed fat in insulated bags inside the hydrogel without reducing the adhesion work of the coating.

Other common additives known in this technique, such as preservatives, antioxidants, pigments, fillers minerals and mixtures thereof may also be included within the adhesive compound in amounts that reach 10% in weight of each of them, respectively.

In accordance with the present invention, the polymer component of the adhesive may be physically crosslinked or chemically in order to form the matrix 3-dimensional. Physical crosslinking refers to polymers that have crosslinks that are not covalent bonds chemicals, but are physical in nature, such as areas that they exist in a three-dimensional matrix that has high crystallinity or areas that have a high state transition temperature vitreous. Chemical crosslinking refers to polymers that are linked by chemical bonds. Preferably, the polymer is chemically crosslinked by radiation techniques, such as thermal radiation, E-ray radiation, UV rays, gamma or microwave.

In addition, when they are formed in the system chemical crosslinks, a crosslinker can be found present  polyfunctional and / or a free radical initiator in the premix to initiate crosslinking when irradiation occurs. This initiator can be present in quantities that arrive at 5% by weight, preferably from 0.02% to 2% and, more preferably from 0.02% to 0.2%. Suitable photoinitiators include  of the type α-hydroxyketones and benzyl dimethyl ketals, for example, Irgacure 651 which are believed to form with benzoyl radical irradiation that They start the polymerization. Photoinitiators of this type that are Preferred do not carry substituents in position for the ring aromatic. Especially preferred is the I-hydroxycyclohexylphenyl ketone (available with the Irgacure 184 trade name of Ciba Specialty Chemicals), Darocur 1173 is also preferred (2-hydroxy-2-propylphenyl ketone) and mixtures of Irgacure 184 and Darocur 1173. In addition, also 0.02% to 2% of thermal initiators can be used.

The resulting adhesive compound is mainly hydrophilic. Hydrophobic and phase compounds Mixed depend on the nature of the adhesive components. In addition, a mixture of hydrophilic, or hydrophilic monomers and hydrophobic, may result in a single phase or mixed phase of a minimum of 2 phases. Preferably, the adhesives herein Invention are mixed hydrophilic and hydrophobic phase.

A mixture of monomers that can result in 1, 2 or more phases. The mixed phase adhesives are compounds in which both hydrophobic and hydrophilic components, preferably in both plasticizers and polymers, they form two or more separate phases In these cases, an emulsifier is found preferably present in adequate amount to form stable emulsions between incompatible phases.

While you don't want to be limited by any theory, it is believed that the peel strength improved with liquid stability, particularly with respect to water of the adhesives, is obtained from a mixture of monomers that comprises hydrophilic monomers, for example, polar and / or monomers ionic, preferably, a water soluble ionic monomer and hydrophobic monomers, that is, water insoluble. Preferably, the proportion of hydrophilic monomers to hydrophobic monomers should be in a range of 5: 1 to 1: 5, preferably from 3: 1 to 1: 3 and, more preferably, from 2: 1 to 1: 2 The hydrophilicity and hydrophobicity of a component Monomer is always relative to the other component. Adhesives of Typical hydrogel of the prior art comprise monomers hydrophilic only, as a result of which they have a high proportion of water absorption and do not maintain the adhesion after exposure to excess fluid. While it is not desired to be limited by any theory, it is believed that the presence of a hydrophobic component in the adhesive matrix reduces the water absorption rate of the adhesive. How As a result, the distribution of water absorbed by the adhesive is more uniform As a consequence, a water film is not generated between the surface of the skin and the adhesive, which, in case if it existed, it would prevent the formation of bonds between the skin and the adhesive and, therefore, its own adherent capacity adhesive.

Therefore, the present invention is proposed disclose a homogeneously dispersed reaction mixture comprising both hydrophobic and hydrophilic components that, in polymerization, it is separated into a biphasic structure or multi-phase It was observed that the phases have, in some cases, an approximate thickness of 100 microns +/- 50 microns. The mixture of reaction may contain one or more surface active agents that may  help or may favor phase separation, but in the course of the polymerization are anistropically distributed among the resulting phases.

The presence of a monomer or polymer hydrophobic may be necessary in the initial homogeneous dispersion in order to more effectively promote the separation of phases

It is a consequence of the present invention that the phase separated material contains relatively regions hydrophobic, which allow the polymer to function as pressure sensitive adhesives, and regions substantially hydrophilic, which allow the surfactant to work in an aqueous medium at the interface between the polymer and the skin of the mammal. When the polymer is placed in contact with the skin, the nature and quantity of the surfactant are chosen to produce the elimination of natural or synthetic hydrophobic material,  such as skin lipid or skin cream, surface of the skin without adversely decreasing adhesion work between the hydrophobic domains and the skin surface. Given the both the polymer adhesive formed in the present invention and the skin with which it makes contact are deformable in the normal use conditions, a situation of balance between phases, in which a certain will take place spatial exchange of hydrophobic regions and regions hydrophobic on the surface of the skin.

They are suitable preferred hydrophilic monomers Acrylic acid and its salts, 2-acrylamide acid methylpropan sulfonic, acrylic acid (3-sulfopropyl) ester, and salts and combinations of the same. An especially preferred example is sodium salt of the acid 2-acrylamide-2-methylpropan sulfonic, usually known as NaAMP available commercially from Lubrizol in the form of an aqueous solution 50% (reference code LZ 2405) or a 58% solution (code reference LZ 2405 A). They are hydrophobic monomer components suitable methyl-, ethyl-, n-butyl, hexyl, iso octyl- and isodecyl acrylates and methacrylate, vinyl ethers, vinyl pyrrolidone,  glycidyl acrylate and ethoxy ethyl acrylate, tetrahydrofurfuryl acrylate, hydroxypropyl acrylate, vinyl propionate and vinyl butyrate, and combinations of same. Especially preferred are ethoxy ethyl acrylate or butyl acrylate

When the adhesive comprises a component hydrophobic, such as butyl acrylate as well as a monomer hydrophilic (i.e. the water-soluble ionic monomer before mentioned), such as NaAMPS, the presence of a soluble monomer in non-ionic water, for example, NNDMA is preferable to act as a so-called "reactive solvent bridge" to provide an intimate mix of the different components apparently incompatible reaction mixture before polymerization. The reaction mixture therefore has a homogeneous structure. which contains hydrophilic and hydrophobic components that are intimately mixed, since NNDMA acts as a solvent for both hydrophilic and hydrophobic materials, providing a transparent compatible coating solution or dispersion. To the polymerize the reactive solvent bridge and being removed, by therefore, essentially of the reaction mixture, the stability of the system is adversely affected and solutions or dispersions of the compatible coating suffer phase separation, providing a diphasic structure.

In a preferred embodiment of the invention, the above-mentioned non-ionic, water soluble monomer will comprise  at least one mono- or di-N-alkylacrylamide or the like. He term "analog" in this context refers to non-monomers ionic, water soluble, containing an alkyl or alkyl group substituted linked to a double bond carbon-carbon with intermediate of an amido function or alkylamido (-CO.NH- or CO.NR-). They are included among the examples of said diacetone acrylamide analogs (N-1,1-dimethyl-3-oxobutyl-acrylamide), N-alkylated acrylamides, acrylamides N, N-dialkylated, N-vinyl pyrrolidone and acryloyl morpholine. The N, N-dimethylacrylamide (NNDMA) and / or analogs of the same. The reaction mixture preferably comprises 15% to 30% approximately and, ideally, from approximately 15% to 25%, by weight of the reaction mixture of the water soluble monomer, not ionic.

The term "reactive solvent bridge" that used in this description refers to a monomer soluble in water, nonionic, partially lipophilic that has the ability to division between the hydrophobic and aqueous phases, so that the hydrophobic monomer is substantially solubilized in the mixture of homogeneous reaction before starting the polymerization. The bridge solvent is reactive because it is a monomer polymerizable that takes part in the polymerization reaction. Without wishing to be limited by any theory, it is believed that the function Solvent bridge of water-soluble, non-ionic monomer is predominantly exerted before the polymerization reaction and in the initial phases of it, and it is reduced by continuing the polymerization reaction.

In the preparation of adhesive compounds of according to the invention, the ingredients will usually be given mixed to achieve a homogeneous reaction mixture in form of an initial liquid formulation, based on a aqueous pre-gel and this is converted below in a gel by a free radical polymerization reaction. This can be achieved, for example, using primers. Conventional thermal and / or photoinitiators or radiation ionizing Photoinitiation is a preferred method and will be applied usually subjecting the reaction mixture pre-gel, which contains a photoinitiation agent appropriate to UV light, after being extended or applied as coating in the form of a layer on release paper siliconed or other solid substrate. The intensity of UV radiation incident, at the wavelength in the range of 240 to 420 nm, is ideally 400 mW / cm2. The process will be carried out in general in a controlled manner, involving a sequence predetermined and precise mixing and heat treatment or record.

The UV irradiation time should ideally be less than 60 seconds, and preferably less than 10 seconds to form a gel with a conversion greater than 95% of the monomers, and for a conversion greater than 99.95% of exposure to UV light less 60 seconds and preferably less than 40 seconds. Technicians in the matter they will appreciate that the magnitude of irradiation will depend of the thickness of the reaction mixture, concentration of photoinitiator and nature of the substrate on which it is applied as coating the reaction mixture and the UV source.

These times are for arc lamps of medium pressure mercury as the source of UV running at 100 W / cm The intensity of UV @ 254 nm and 313 nm that reaches the substrate surface is approximately 150 µW / cm2 and 750 µW / cm2. For a given lamp, the UV intensity It is a function of the operational action itself and the distance of the Reactive mixture with respect to the UV source.

To minimize and preferably eliminate the presence of any residual monomers, it is important ensure that the reaction is over. This depends on a series of factors such as the substrate on which the adhesive, the type and intensity of ultraviolet light and the number of past of ultraviolet light. Preferably, the conversion of The hydrophilic monomers present, such as NaAMPS, must be 98%, preferably 99% and more preferably 99.9%, so that the amount of monomer inside the adhesive is 4600 microg / g or less, preferably 2300 microg / g or less, more preferably 230 microg / g or less. Similarly, the conversion of the hydrophobic monomers present such as NNDMA, must be 99%, preferably 99.9% and more preferably 99.99%, of so that the amount of monomer present in the adhesive is of 2200 microg / g or less, preferably 220 microg / g or less, more preferably 22 microg / g or less.

The adhesive is therefore formed of typical way by polymerization of an aqueous reaction mixture  homogeneous comprising from 5 to 50%, preferably from 30% to 50% in weight of the hydrophilic monomer reaction mixture, that is, a ionic water soluble monomer, from 10% to 50%, preferably from 15% to 45% by weight of the reaction mixture of a plasticizer (other than water), up to 50%, preferably 10% to 50%, more preferably from 15% to 30% and more preferably from 15% to 25% in weight of the reaction mixture of a monomer, nonionic, soluble in water up to 40%, preferably 0.05% to 40%, more preferably from 3 to 40% by weight of the reaction mixture, of water. If the The present reaction mixture comprises up to 10%, preferably of 0.05% to 9%, and more preferably less than 8% by weight of the mixture reaction of a surfactant. Similarly, the mixture of reaction may also comprise from 0.1% to 5% by weight of the mixture reaction, of a lipid micellant polymer, and can comprise at least 1% to 30% by weight of the reaction mixture of a hydrophobic monomer.

The term "aqueous reaction mixture homogeneous "used in this description refers to a substantially solubilized system in which substantially no phase segregation takes place before the reaction of polymerization. For example, an emulsion, microemulsion or mixture of separate phase in which a polymerization reaction takes place subsequent is not a homogeneous aqueous reaction mixture, as it is comprises for the purposes of the present invention. If that the reaction mixture includes hydrophobic components, they will have to take special measures to achieve homogeneity, as described in more detail.

Surface characteristics of the materials polymerized

It is a consequence of the present invention that the polymerized material with phase separation contain at least relatively hydrophobic regions on its surface, which allow that the polymer functions as a pressure sensitive adhesive, and substantially hydrophilic regions that enable the agent surfactant works in an aqueous medium at the interface between the polymer and mammalian skin. When the polymer is put in skin contact, the nature and amount of surfactant they are chosen to achieve the elimination of hydrophobic material synthetic or natural, such as skin lipid or skin cream skin, from the surface of the skin without diminishing so unfavorable adherence work between domains hydrophobic and skin surface. Since both the adhesive polymer formed in the present invention as the skin with which contact sets are deformable under conditions of use normal, a situation of equilibrium between phases is created in which a certain spatial exchange of hydrophobic regions will take place and hydrophobic regions on the surface of the skin.

The surfactant polymerized with phase separation is observed to include hydrophobic phases predominantly well defined, embedded in a matrix hydrophilic, in which water is predominantly contained. The hydrophobic phases have a generally elongated shape, with a dimension transverse above the wavelength of light (by example, about 0.5 to 100 microns). Therefore, it they can visualize with a light microscope on a sample stained with a dye that preferably binds to the phase hydrophobic

The superficial morphology of the phases Elongated hydrophobic can vary widely. Not wanting to stay limited by any theory, it is believed that variations of the surface tension at the hydrophobic / hydrophilic interface, at take place the polymerization reaction, can cause the Morphologies vary in the final polymer. This surface tension may be affected by the nature and amount of both the bridge reactive solvent such as surfactant, and other factors.

Therefore, it is possible that the phases elongated hydrophobic of the surface of the polymerized material is  meet in a group arrangement, or alternatively in a relatively open layout. The hydrophobic phase visualized microscopically it can appear, for example, as linear bands and / or discontinuous branched, or closed loops, embedded in the hydrophilic matrix

The polymerized material is typically not bicontinuous At least one of the hydrophobic phases and hydrophilic exists in the form of discrete regions within the polymerized material, and both phases do not extend simultaneously  on the polymerized material (bicontinuity).

The adhesive is arranged, typically so less on a part of the surface of the device directed to the user, as a layer with thickness or gauge C preferably constant, or alternatively it may vary on the surface of adhesive application.

When the phase of removal of an adhesive compound for fixation on the skin of a user, it is usually recognized that they get good removal conditions, that is, an approximate frequency of 100 rad / sec, of the adhesive applied at least in a part of the surface of the device aimed at the user, when the adhesive it can be easily removed from the skin and, particularly, from the body hair that may exist in this area of the skin, in which the device establishes contact with the body, without causing pain to the user, therefore, without adhering too much resistant in removal to the skin and hair of the user. In addition, a satisfactory removal or removal implies that the adhesive does not Leaves residue on skin or hair.

The ratio between the thickness or gauge C measured in millimeters (mm) of the adhesive layer, typically over at least a part of the surface of the device directed to the user, and the G''25 viscosity module at 25 ° C at about 100 rad / sec of the topical adhesive, provides an indication of easy removal and no pain of the adhesive with respect to the skin.

Without wishing to be limited by any theory, It is believed that for higher values of G''25 to 100 rad / sec, that, in general, they correspond to a superior adhesion of the compound, a higher gauge or thickness C of the layer is needed adhesive, so that the energy applied for withdrawal or elimination is distributed more regularly within the mass of adhesive and, therefore, is transferred more gently to the skin, avoiding, therefore, maximum energy values that typically They cause a sensation of pain in the user. In other words, the Thin layers of adhesive require adhesion with values Bottoms of G''25 to 100 rad / sec to get a feeling reduced pain in the withdrawal of the device.

Test methods Peel Adhesion Method

This is a quantitative method to determine the average peel strength, required to remove an item laminate the skin according to a peeling angle and speed specified.

quad

Team

Scissors

Convenient supplier

Standard rule

Convenient supplier

Roller steel

Weight 0.5 kg, diameter 13 cm and 4.5 cm wide with 0.5 mm rubber coating.

Movie polyester

PET 23 µ of the firm EFFEGIDI S.p.A, 43052 Colorno, Italy.

Adhesive transfer

3 M 1524 of the 3M signature Italia S.p.a, 20090 Segrate Italia.

Chronometer

Convenient supplier

Tester traction

Instron mod: 6021 (or equivalent)

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Test procedure A) Stripping tester stripping settings

Cell load

10 N

Speed of verification

1000 mm / min

Jaw distance a jaw

25 mm

Preload

0.2 N

Test path "LM"

50 mm

Measurement variable

F average (N) in "LM"

B) Skin condition and preparation

The sample is removed by stripping the forearm. Three skin conditions are checked:

1) Dry: The forearm has not been treated or has cleaned before the test or between repetitions.

       \ newpage
    

2) Wet: It is added to a cotton pad (Demak'up diameter 5.5 cm, approximate weight 0.6 g), 3 ml of water distilled Then the disc is scrubbed with a pressure Light three times over the forearm testing area. (The area of forearm testing is approximately a rectangle that has 2 cm more width and length than the adhesive area).

3) Greasy: They are added to a cotton disk (Demak'up diameter 5.5 cm, approximate weight 0.6 g) 4 drops (approximately 0.2 g) of "Nivea Body". The disk is folded to continuation on itself to ensure that the cream is absorbed.  Then the disc is scrubbed with light pressure three times over the test area on the forearm. (The testing area of forearm is approximately a rectangle that has 2 cm more than width and length than the adhesive area).

C) Sample preparation

1. Let the samples adapt to the environmental conditions (23 ± 2 Celsius and 50 ± 2% RH) during About an hour.

2. Prepare rectangular adhesive samples 260 mm ± 2 in length and 20 mm ± 2 in width.

3. Fix on the sample surface the polyester film (using the transfer adhesive to fix the polyester to the surface of the substrate).

4. Each of the samples must be prepared individually and tested immediately.

5. Remove the removable paper from the adhesive without touching it Fix one end to the skin (see section B).

6. Roll the steel roller along 160 mm according to the adhesive strip, once in each direction.

D) Test medium

There are 2 means of proof in which you can test the adhesive:

1) Conditioning enclosure according to C1.

2) Wet environment. In this case, after the step C4, the sample is removed and placed in a stove with humidity controlled for 3 hours at 85 ° C. It is then taken out and carry out steps C5, C6.

E) Realization

One minute after stage C6, the free end of the sample (approximately 100 mm length) and it inserted into the upper end of the machine checking adherence. It will ensure that the sample is forming a 90º angle to the forearm. Start the machine Check

F) Registration

Record the average resistance to stripped of five tests. Individual values are the basis for Calculate the standard deviation between the samples.

Residual monomer test method Sample of evidence

A sample of 1 gram of hydrogel is taken and immerse in 100 ml of 0.9% saline water.

The sample is left in the saline solution at 40 ° C for 24 hours

An aliquot of the liquid is diluted and analyzed by LC / MS / MS electrospray.

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Calibration sample

1 gram of the reference monomers (per example, NaAmps) is dissolved in 100 ml of saline solution at 0.9%

An aliquot of the liquid is diluted and analyzed by LC / MS / MS electrospray.

Evaluation

The concentration of the test and the sample of calibration are determined by linear regression analysis using a set of software such as VG Mass Lynx.

Examples

All formulations indicated below in detail they were applied as a coating on foam of polyurethane (EV1700X from Caligen) with a coating weight of 0.8 at 1.6 kg per square meter, and exposure curing was performed to ultraviolet radiation emitted from an arc lamp of medium pressure mercury, operating at a power of 100 W / cm for 10 seconds

Example one

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.5 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add 30 g of glycerol to the above and stir for 5 minutes, followed by 40 g NaAMPS (58%). Shake for another 5 minutes. Add 0.13 g of solution A and stir the total formulation for 1 hour before utilization.

Example 2

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.5 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add to it 10 g of Mowilith DM137 (50% dispersion of ethylene copolymer Vinyl acetate in water of the Harco brand and stir for 5 minutes. Add 30 g of glycerol to the above and stir for 5 minutes, followed by 40 g of NaAMPS (58%). Shake for another 5 minutes. Add 0.13 g of solution A and stir the total formulation for 1 hour before use.

Example 3

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.5 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add to it 10 g of Mowilith DM137 (50% dispersion of ethylene vinyl copolymer acetate in water from Harco) and stir for 5 minutes. Add 30 g of glycerol and stir for 5 minutes, followed by 40 g NaAMPS (58%). Shake for another 5 minutes. Add 0.5 g of Pluronic L64 poly (ethylene glycol) -block-poly (propylene glycol) -block-poly (ethylene  glycol) commercially available from BASF). Add 0.13 g of solution A and stir the total formulation for 1 hour before of use.

Example 4

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.4 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add to it 2 g of Mowilith DM137 (50% dispersion of ethylene vinyl copolymer acetate in water from Harco) and stir for 5 minutes. Add 36 g of glycerol to it and stir for 5 minutes, followed of 40.36 g of NaAMPS (58%). Shake for another 5 minutes. Add 0.5 g Pluronic L64 (poly (ethylene glycol) -block-poly (propylene glycol) -block-propylene glycol-block-poly (ethylene glycol) from the firm BASF). To this add 0.8 g of a solution 30% aqueous poly sodium salt (styrene-alt-maleic acid) available from Aldrich and stir for 10 minutes. Add 0.13 g of solution A and stir the whole formulation for 1 hour before utilization.

Example 5

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.4 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add to it 10 g of Mowilith DM137 (50% dispersion of ethylene vinyl copolymer acetate in water from Harco) and stir for 5 minutes. Add 36 g of glycerol and stir for 5 minutes, followed by 40.36 g of NaAMPS (58%). Shake for another 5 minutes. Add 0.25 g Pluronic L64 (poly (ethylene glycol-block-poly (propylene glycol) -block-poly (ethylene  glycol) available from BASF). Add 0.8 g of a solution 30% aqueous poly sodium salt (styrene-alt-maleic acid) available from the firm Aldrich and stir for 10 minutes. Add 0.13 g of solution A and shake the whole formulation for 1 hour before utilization.

Example 6

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.4 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add 10 g of Mowilith DM137 (50% dispersion of ethylene vinyl copolymer acetate in water from Harco) and stir for 5 minutes. Add 36 g of glycerol and stir for 5 minutes, followed by 40.36 g of NaAMPS (58%). Shake for another 5 minutes. Add 0.5 g Pluronic L64 (poly (ethylene glycol) -block-poly (propylene glycol) -block-poly (ethylene glycol) from the firm BASF). Add 0.8 g of an aqueous solution to the 30% poly (ethylene-alt-molecular acid) sodium salt from the Aldrich firm and stir for 10 minutes. Add 0.13 g of solution A and shake the formulation as a whole for 1 hour before use. Optical phase contrast microscopy showed that the resulting gel regularly had a surface of segregated phase (see figure 1).

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Example 7

Mix 6.0 g of Irgacure 184 with 20 g of IRR280 (PEG400 diacrylate) from UCB (Solution A). At 0.07 g of Irgacure 184 23.4 g of NNDMA is added and stirred for one hour (keep the container protected from light). Add to it 20 g of Mowilith DM137 (50% dispersion of ethylene vinyl copolymer acetate in water from Harco) and stir for 5 minutes. Add 36 g of glycerol and stir for 5 minutes, followed by 40.36 g of NaAMPS (58%). Shake for another 5 minutes. Add 0.5 g Pluronic L64 (poly (ethylene glycol) -block-poly (propylene glycol) -block-poly (ethylene  glycol from BASF). Add 0.8 g of an aqueous solution to the 30% sodium salt of poly (ethylene-alt-acid maleic) available from Aldrich and shake for 10 minutes. Add 0.13 g of solution A and stir the whole formulation for 1 before use.

Example 8

To parts of glycerol were added 40.4 parts of a 58% solution of the acidic sodium salt 2-acrylamide-2-methylpropan  sulfonic acid (NaAMPS) (LZ2405A) together with 0.5 parts of Pluronic LF64 (BASF), and the solution was stirred to ensure uniform mixing. 0.13 parts of solution containing 20 were added to the solution polyethylene glycol diacrylate parts (PEG600) (UCB product Chemicals, marketed under the trademark Ebacryl 11) in the that 6 parts of 1-hydroxycyclohexylphenyl ketone (product of Ciba and marketed under the brand name Irgacure 184). A premixed solution of 8 parts butyl acrylate and 15.7 parts  of N, N-dimethylacrylamide (Kohjin) were added to this reaction mixture and this final solution was cured by exposure to UV light as in example 1. The application of optical microscope with phase contrast showed that the gel resulting had a surface with regular phase segregation and improved adhesion to the skin, which had been previously treated with skin cream (Nivea) (see figure 2 below).

Example 9

To 30 parts of glycerol were added 0.5 parts of a 30% aqueous solution of poly (styrene-alt-molecular acid) sodium salt of Aldrich and 40 parts of a 58% solution of the sodium salt of acid 2 -acrylamide-2-methylpropan sulfonic (NaAMPS) (LZ2405A) together with 0.5 parts of Pluronic P65 (BASF) and the solution was stirred to ensure a uniform mixture. 0.13 parts were added to the solution containing 20 parts of polyethylene glycol diacrylate (PEG600) (product of UCB Chemicals sold under the trademark Ebacryl 11) in which 6 parts of 1-hydroxycyclohexalphenyl ketone had been dissolved (product of Ciba and marketed under the commercial designation Irgacure 184). A premixed solution of 6 parts of ethoxyethyl acrylate and 18 parts of N, N-dimethylacrylamide (Kohjin) were added so that the reaction mixture and this final solution were subjected to curing by exposure to UV radiation as in Example 5. The Optical microscope application showed that the resulting gel had a surface with regular phase segregation (see figure 7 and the explanation below
nation).

Results

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100

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Microscope

The gels of examples 6, 8 and 9 were examined using a Leitz Dialux 20 microscope with a camera docked "Wild MPS photoautomat". The microscope was gifted of a 12.5 X eyepiece. The image can be enlarged by a number of objectives of which the most commonly used were x4, x10 (phaco) and x25 (phaco). Phase e contrast was used bright lighting.

Had

The sample of example 9 was stained before the Microscope observation. A saturated red solution of Bromopyrogalol in methanol was used to dye so differential hydrophobic areas of the hydrogel surface. The solution is applied to the surface of the sample, which is then rinsed with methanol to remove any excess of dyeing solution and dyed solid. The criteria used in the selection of dyes are indicated below.

The selection of a dye to dye differentially the most hydrophobic and most hydrophilic areas of These gels are influenced by many factors, which can, be illustrated by a comparison of bromopyrogalol red and sodium fluorescein that were preserved in varying degrees in Different types of polymers. The two main factors are the load and hydrophobicity. The bromine red, pyrogallol is dominated by acid groups -SO3H and -COOH, and sodium fluorescein by a slightly acid group -COOH. The most basic polymer zones they have the highest affinity for acid dye and acid areas Less affinity for acid dye. You can also see that a material with a higher water content allows absorption faster dye. In conventional hydrogels, it comes influenced by the fact that water content materials higher will often contain slightly basic groups n-vinyl pyrrolidone or N, N-dimethylacrylamide that attract dyes that they contain acidic groups, for example, -SO3H and -COOH.

Like the acidity and basicity of the dyes and of the polymers, the partition coefficients of the dyes they also have a marked effect on their retention Inside the materials. This property is characterized by conventional and usual way by measuring the coefficient of Dye partition between octanol and water (KOW). The red of Bromopyrogalol has a KOW log of -0.49, and sodium fluorescein It has a KOW log of -0.98. Both dyes are capable of partition between the aqueous and non-aqueous components of the polymers used

However, bromopiengalol red appears more likely in the more hydrophobic phase than the more aqueous phase hydrophilic, compared to sodium fluorescein that I would prefer the aqueous medium. This preference is illustrated by the fact that hydrogels conventions based on N-vinyl pyrrolidone or N, N-dimethylacrylamide tend to retain approximately 30% of the bromopyrogalol red dye inside the polymer network.

The most intense color of bromopyrogalol red coupled with its highest affinity for hydrophobic domains and its methanol solubility make it much more suitable than the sodium fluorescein to indicate by differential staining the presence of hydrophobic and hydrophilic regions on the surface of polymer gels.

Coating layer

Before using an adhesive present in the face of the face mask (10) addressed to the user, is coated  preferably by a layer that can be constituted, by for example, by a removable sheet (40) or removable paper, such like silicone paper.

In accordance with the present invention, it has been discovered that it is very preferable to arrange a coating layer  for an article for the respiratory organs of the user of a minimum of two removable sheets (40).

Preferably, any of said sheets removable (40) extends from the outer periphery (24) of the tab (20) to the filter layer (30), and more preferably to the central point of the facial mask (10). This realization allows peelable removal of the removable sheet (40), starting from the center instead of starting from the outer periphery of the face mask (10).

In very preferred embodiments of the present invention, the removable sheets (40) are provided with edges straight, which most preferably are parallel to the axis Longitudinal face mask. This realization has been shown in figure 3.

It is also preferable that the removable sheet (40) provide overlap with the coating layer, so that at least a part of at least one of the removable sheets is not in contact with the adhesive, in order to facilitate easier separation by peeling. The external contours of the removable sheets (40) can be chosen so that they have the same shape as the outer periphery (24) of the flange (20) or it they can choose so that they have another way that is comfortable to manufacture.

It has been discovered that the face mask (10), In accordance with the present invention, it provides the best coupling and comfort if the adhesive contact of the flange (20) It is done, first, in the nasal area and the chin area of the user, and the adhesive contact in the cheek area and around the corners of the mouth is done later. This facilitates the symmetrical application of the facial mask (10) so that the longitudinal axis of said facial mask (10) matches the axis of symmetry of the user's face. The provision of a minimum of two removable sheets, which has been explained above, allows the user to apply the facial mask (10) in this preferred manner.

While a coating layer made by a minimum of two removable sheets (40) it is very beneficial as soon as it is used as a face mask (10), such as indicated above, this coating layer can be also used beneficially for any other article intended to cover the respiratory organs of a Username. Such items include anti-noise devices, for example, those disclosed in the patent application European pending 00120457.7 (bearing the CM agent number 2409 CF).

Claims (9)

1. Respiratory facial mask (10), comprising a flange (20) and an air control module (30), said flange (20) having an internal periphery (22) and an external periphery (24) as well as a first and second widths measured perpendicularly to said inner periphery (22) between said inner periphery (22) and said outer periphery (24), characterized in that said first width is greater than said second width, said second width being measured on the cheek part (27) and / or in the corner part (28) of the mouth, and said air control module (30) being provided with stretchable means (32). 2. Respiratory facial mask (10) according to claim 1, characterized in that the first width is at least 10% greater than said second width. 3. Respiratory facial mask (10) according to any of the preceding claims, characterized in that said first width is measured in the central nasal part (26) and / or in the part of the central chin (29). 4. Respiratory facial mask (10), according to any of the preceding claims, whose flange comprises a side directed to the user and a side directed to the garment, characterized in that the user directed side of said flange (20) is provided with a layer of adhesive. 5. Respiratory facial mask (10) according to claim 4, characterized in that said adhesive is a hydrogel adhesive. 6. Respiratory facial mask (10) according to claim 5, characterized in that said adhesive is a pressure sensitive adhesive substantially insoluble in water, comprising a polymer forming a three-dimensional matrix, and comprising less than 10%, preferably less 5%, by weight of said hydrocolloid particle adhesive. 7. Respiratory facial mask (10) according to claim 5, characterized in that said adhesive comprises - a polymer selected from acrylics, sulfonated polymers, vinyl alcohol, vinyl pyrrolidone, oxide polyethylene or mixtures thereof and - a plasticizer selected from alcohol polyhydric, polyethylene glycol, sorbitol, water or mixtures of same. 8. Apparatus for controlling inhaled air, such as an apparatus for artificial respiration, comprising a respiratory facial mask (10) according to any of the previous claims. 9. Apparatus for analysis of the expelled air, such as an alcohol tester, which comprises a face mask respiratory (10) according to any of the claims previous.