CN1501779A - Strapless respiratory mask - Google Patents

Abstract

The present invention relates to a mask for controlling and improving the quality of inhaled air. What is claimed and described is a respiratory mask that includes a flange and a filter layer. The flange having an inner edge and an outer edge, and a first width and a second width between the inner edge and the outer edge and measured orthogonal to the inner edge, characterized by: the first width is greater than the second width. More preferably, the mask is strapless and instead is secured and closed onto the face by a hydrogel adhesive. Further claimed and described are: improved coverings for such mask adhesives.

Description

Strapless breathing mask

field of invention

The present invention relates to a mask for controlling and improving the quality of inhaled air. What is claimed and described is a breathing mask including a flange and a filter layer. The flange has an inner edge and an outer edge, and a first width and a second width measured between the inner edge and the outer edge and perpendicular to the inner edge, wherein the first width is greater than the second width. Even better, the mask is strapless, instead relying on a hydrogel adhesive to secure and seal the mask to the face. Further claimed and described are improved cover layers for such mask adhesives.

Background of the invention

Many face shields are already known in the industry and seen on the market. Including reusable and disposable masks, medical masks, especially for surgeons, masks for professionals whose work environment requires the use of masks to inhale air, and personal masks, such as to prevent the spread of infection, these masks are used in Asian countries The most widely used.

Prior art in the field of face masks is included in the following documents:

US 4,966,140, issued October 30, 1999, discloses a protective surgical mask comprising substantially vertical fastening straps and a seal along the upper edge.

US 5,735,270, issued on April 7, 1998, discloses a disposable foldable mask, which includes a roughly rectangular filter material sheet and a foam seal, and a mask knotted part connected to the upper two corners.

US 5,724,964, issued March 10, 1998, discloses a disposable face mask which is secured to the wearer's head by a braided headband. Face masks use a variety of gasket-type sealing materials, such as plastic films, and/or hydrogels or other deformable types of materials, such as open cell and closed cell foam materials. In particular, hydrogel-based adhesives are not contemplated in this invention.

JP10-248,948, filed March 11, 1997, discloses a nose and mouth covering mask that includes adhesive material around the edges of the mask.

WO00/07636, filed 30 July 1999, discloses novel hydrogel adhesives, particularly suitable for disposable absorbent articles, but also suitable for use in respiratory masks.

US 4,240,420, issued December 23, 1980, and its continuation-in-part US 4,354,4889, issued October 19, 1982, disclose filtering masks comprising separate filter elements for the wearer's mouth and nose.

The state of the art in the general application of adhesives for fixing to the skin has developed in particular in articles such as Band-Aids, adhesive plasters and bandages.

In order to provide the adhesiveness required for such bandages, the prior art generally discloses the use of certain adhesives such as rubber-based adhesives and acrylics with very high bond strengths. These adhesives are then applied in thick layers, strengthening its bond and keeping the bandage in place on the wearer's skin.

US 4,699,146 discloses a hydrophilic elastic pressure sensitive adhesive suitable for use with Ostomy device bandages, ulcer pads, sanitary napkins, diapers and sports pads. The adhesive comprises at least one radiation crosslinked organic polymer and an adhesive plasticizer.

GB 2 115 431 discloses adhesives for bandages, wound or burn dressings, adhesives for electrocardiogram measurements, sanitary napkins, diapers and ulcer pads. The adhesive includes a radiation crosslinking organic polymer, such as polyvinylpyrrolidine, and an adhesive plasticizer.

However, in order to use an appliance like a respirator satisfactorily, i.e. to be worn for an extended period of time, it is important that the adhesive has a skin-compatible composition that does not roughen or damage the skin, or cause skin irritation or inflamed. It is even more advantageous if the adhesive conforms to the wearer's skin so as to obtain a maximum contact surface between the adhesive and the skin. Furthermore, it would be desirable to provide an adhesive that allows the respirator to be easily removed from the wearer's face without unacceptable pain or residue. This is especially important in some cases, such as when you have to take off the mask one or more times for better communication, eating, etc., and put it on again, ensure that the mask is worn on sensitive skin (such as an elderly wearer) Use this mask on your face. On the other hand, however, although it should be painless, the mask's required adhesion will of course be maintained during multiple repeated wearings.

In wet skin conditions, the problem of achieving the desired adhesion becomes more severe. On some occasions, the skin must be cleansed before wearing the mask, so the skin is usually wet. Also, during wearing the mask, for example, due to high ambient temperature, or engaging in strenuous physical labor, sweating increases. Existing adhesives, such as those containing hydrogel particles, often do not immediately adhere firmly to the skin, but need to be fixed in place until sufficient minimal adhesion develops. Furthermore, the overall bonding capacity of such adhesives is significantly reduced on an already moist skin surface. Such application of pressure to the mask during wear, such as by facial movements, generally fails to maintain affixation to the skin.

Another particularly common problem in the use of respiratory masks is the ability of the adhesive to adhere to oily skin surfaces. The amount and type of oils and sebum naturally present on the skin vary from person to person. Also, the adhesive should adhere reliably to hairy skin and be peelable painlessly.

For example, WO-A-97/24149 (3M) describes a lipophilic polar pressure sensitive adhesive which is said to have increased adhesion to oily skin. The adhesive comprises a hydrophilic polymer matrix, a polar organic plasticizer and at least 9% (w/w) surfactant having a HLB between 10-17. It is pointed out that the hydrophilic polymer matrix can be selected from a group of polymers including homopolymers and copolymers, for example, (meth)acrylic acid and its salts, acrylamide, N-vinylpyrrolidone and arylaminopropane Sulphonic acid and its salts. The adhesive is produced by polymerization in a homogeneous water mixture.

In view of the above prior art, there remains a need to provide an improved respiratory mask. It needs to serve the following purposes:

-The mask is comfortable and safe to wear.

- The mask is cheap to manufacture and can be used as a single-use item, however on the other hand it can be reused many times.

- The mask facilitates facial movements, i.e. opening the mouth at least slightly, speaking, coughing, etc., while maintaining a reliable face seal.

- Face shields are available in sizes that fit a broad range of consumers.

-Masks function well on wet, oily, and especially hairy skin.

- The mask adheres reliably to the human skin for an extended period of time.

- The mask can be easily and comfortably removed.

Another object of the present invention is to provide the adhesive layer with a cover that the mask preferably includes that is easily peelable from the adhesive for optimal adhesion of the mask to the wearer's face.

It has now surprisingly been found that the above objects can be achieved by providing a breathing mask and a cover layer for an adhesive layer on the mask, the mechanical properties of the adhesive and the adhesives preferably contained are described hereinafter.

Summary of the invention

The present invention relates to a mask for controlling and improving the quality of inhaled air. What is claimed and described is a respiratory mask including a flange and a filter layer. The flange has an inner edge and an outer edge, and a first width and a second width measured between the inner edge and the outer edge and perpendicular to the inner edge, wherein the first width is greater than the second width. Even better, the mask is strapless, and instead relies on a hydrogel adhesive to secure and seal the mask to the face. Further claimed and described are improved cover layers for such mask adhesives.

Brief description of the drawings

It is believed that the invention will be more clearly understood in conjunction with the following drawings.

Figure 1 is a front view on the side of the wearer's face of the preferred embodiment of the invention.

Figure 1a is a front view on the face side of the wearer of the preferred embodiment of the invention, this figure also shows that the axis A delimits the sector on the flange.

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

Figure 3 is a front view on the side of the wearer's face of the preferred embodiment, the adhesive being provided by release paper.

Detailed Description of the Invention

summary

The present invention relates to a face mask for controlling and improving the quality of inhaled air, which is sometimes called a breathing mask, and is also referred to here as a face mask (10) or a hood (10) for brevity. The cover comprises at least one flange (20) and at least one air control module, such as a filter layer (30), which may be integral or connected, and which may be a removable or non-removable piece.

The breathing mask (10) of the present invention can be designed to only seal the mouth of the wearer or only the nose of the wearer, but is preferably designed to seal these two respiratory organs, and possesses known fixing means in the art, such as Headbands or straps wrap around the head and neck or around the wearer's ears. The preferred fixing method according to the present invention is an adhesive fixing method, such as providing a layer of adhesive on the wearer's face side of the flange (20).

Furthermore, the breathing mask (10) can be provided with sealing means known in the art, such as foam materials. However, in a preferred embodiment of the present invention, an adhesive layer is provided on the mask (10), which acts both as a fixation and as a seal.

The breathing mask (10) provided by the present invention is hereinafter referred to as protective mask (10), the mask (10) or hood (10) comprising the main key elements - the flange (20) and the filter layer (30). Figures 1 and 2 show a preferred embodiment. These embodiments are initially suitable for use in disposable face masks for personal protection against infection.

flange

Flange (20) seals and preferably secures cover (10) to the wearer's face. The flange is not intended to cover the wearer's respiratory organs (mouth and nose). If the flange is designed to cover the wearer's mouth and nose, then typically the flange contacts the wearer's nose, cheek, and chin.

The flange has an inner edge (22) surrounding the wearer's respiratory organs and an outer edge (24) which generally defines the outer contour of the mask (10), see FIGS. 1 and 2 .

An aspect of the present invention is to provide a mask (10) with a substantially improved flange (20). It has surprisingly been found that providing the mask (10) with flanges (20) of varying edge width greatly improves the seal of the mask (10) to the wearer's face.

The term "width" as used herein refers to the distance between the inner edge (22) of the flange (20) and the outer edge (24) of the flange (20), measured perpendicular to the direction of the inner edge (22).

More specifically, it has been found beneficial to have a greater width in the portion of the flange (20) adjacent the nasal bones and center of the chin of the wearer. It has further been found to be beneficial to have a narrower width in the portion of the flange (20) between the wearer's nose and cheeks, and at the corners of the mouth. Accordingly, it is an aspect of the invention that the first plurality of widths measured across the flange is greater than the second plurality of widths measured across the flange. Preferably at least one of the above-mentioned first widths is at least 10% larger than at least one of the above-mentioned second widths, more preferably at least 20% larger, still more preferably at least 30% larger, even more preferably at least 40% larger, even more 50% larger %, preferably 80% larger.

The breathing mask (10) provided according to the invention is preferably symmetrical about the longitudinal axis reflecting the symmetry of the left and right sides of the human face. The central point adopted here, as shown in FIG. 1a, is the point on the longitudinal axis from the outer edge of the nose (26) to the outer edge (29) of the middle of the chin.

With regard to the angle measured clockwise between the longitudinal axis and the reference axis intersecting at the center point (see figure (a), the area of smaller width should exist in the following sectors: first the sector of 20°-80° Zone, preferably 30°-70° sector, best 40°-60° sector, and secondly 100°-150° sector, preferably 105°-140° sector, best 110 °-130 ° sector, and there are two corresponding mirror-symmetrical sectors on the other side of the longitudinal axis. These areas are also referred to as the cheek area (27) and the corner of the mouth area (28). Refer to the other side of Fig. 1.

In another important aspect, the aforementioned smaller width flange (20) portion, also referred to herein as the narrow portion of the flange, acts as a hinge to facilitate facial movement. Without wishing to be bound by theory, this hinge action is believed to be due to the higher flexibility of the flange (20) due to the use of less material in the narrow portion of the flange. When strain is applied to the flange (20), the narrower portion wrinkles less than the wider portion. These wrinkles are believed to be the source of the lack of a seal.

The mask (10) of the present invention may have any shape, such as circular, oval, square, rectangular or triangular. An oval shape is preferred. In general, the shape of the mask (10) is primarily given by the outer edge (24) of the flange. If the mask is provided for an adult wearer, the outer edge (24) of the flange (20) should have the following shape, which is between 5-15cm in height along the longitudinal axis, preferably 8-12cm; The measured width of the horizontal axis is 8-20, preferably 10-15cm. The height should be chosen to allow for some facial movement and opening. It has surprisingly been found that eg the face mask (10) of the present invention even allows talking and coughing, which provides both comfort and safety benefits.

It has surprisingly been found that the above-mentioned provisions in the design of the flange (20) provide a greatly improved fit and comfort of the cover (10). In particular, it has been found that, together with the adhesives disclosed below, both improved sealing and secure fixation can be achieved without the use of overly strong adhesives and without relying on further fixation methods according to preferred embodiments of the present invention, Such as strips or bands etc.

Without wishing to be bound by theory, it is believed that providing a smaller width allows the flange (20) to have a generally flat or two-dimensional shape prior to use, to more accurately follow the three-dimensional contours of a person's face without wrinkling. However, such wrinkles are generally detrimental to the sealing of the cover (10).

In some embodiments of the invention, an air control module (30) has more than one flange (20). For example, the flanges (20) may be arranged one above the other so that the used flange (20) can be peeled off to reveal a new flange (20) comprising a fresh layer of adhesive. The superimposed arrangement is joined by an adhesive layer on the flange (20) for fastening to the wearer's face. In this embodiment, only the outermost flange (20) should be covered with the release sheet (40) before use.

air control module

The preferred air control module of the present invention is the filter layer (30). The filter layer (30) may be provided by a wide variety of materials and combinations of materials. Preferred materials include nonwoven materials, woven materials such as silk, hemp or cotton and tissue paper. It can also be any material known to be used in the absorbent article industry, ie sanitary napkins, pantiliners and diapers, for use in the topsheet or backsheet of such absorbent articles. The known materials used as topsheets have good liquid permeability and thus also good air permeability and are also suitable for skin contact. Known materials used as backsheets are generally somewhat less breathable, but recently developed materials are also highly vapor and air permeable and are now fully considered for use. Due to the humidity of the exhaled air, it is most preferred that the material provide good breathability, which avoids a wet feeling during wearing of the mask. On the other hand, the filter layer (30) should be able to better filter out some moisture in the exhaled air, such as traces of saliva or blood, so as to inhibit the spread of infection.

In some preferred embodiments of the present invention, the cover (10) and preferably the filter layer (30) also contain an odor absorbing compound such as activated carbon or zeolite.

The filter layer (30) comprised by the mask (10) of the present invention should be selected to have some flexibility. The flexibility can better fit the contours of the wearer's face, reduce the stress on the adhesive area when the face moves, and facilitate its packaging. The above aspects should be considered for selection.

However, the selected filter layer (30) included in the mask (10) should have some rigidity. According to a particular embodiment of the invention, the rigidity of the flexible sheet prevents the sheet from protruding into the wearer's mouth if opened. Some wearers may find it unpleasant to touch the sheet with their tongue, for example because of the unpleasant taste of the nonwoven material.

If the slightly stiffer, or at least not too thin material has stretching means such as folds (32), the requirement of stiffness on the one hand and flexibility on the other hand can be reconciled. Numerous pleat patterns can be used as stretching devices. Preferably the filter layer (30) immediately adjacent the wearer's mouth has no folds (32). Thus, the folds are preferably located just above the wearer's upper lip and slightly below the lower lip, and the folds may optionally be in the area of the wearer's nose. In a preferred embodiment of the present invention, there are 2 or 4 folds (32) above the wearer's upper lip and below the lower lip, preferably 1 or 2 folds respectively. In the preferred embodiment shown in Figure 2 there are four folds. Although the pleats can be arranged symmetrically, it is better to arrange them asymmetrically so that they are more stretchable in the nose than in the mouth.

In another embodiment of the present invention, the air control module (30) also includes more complex components to control the inhaled and/or exhaled air. In a preferred embodiment of the present invention, the air control module (30) includes control means, specifically for example adding oxygen to the inhaled air, such as used in artificial respiration devices in medical activities. In another preferred embodiment, the air control module (30) includes means for analyzing exhaled air. Such means are designed to analyze trace amounts of alcohol in the feed, such as the method used by the police in alcohol testing. From the perspective of expanding medical purposes, it is also planned to use the method of analyzing exhaled air to judge someone's metabolic level.

In some embodiments of the present invention, the air control module (30) is detachably fixed on the flange (20), so the air control module (30) can be replaced. Replacing the air control module (30) without the mask (10) provides at least the benefit of making the flange (20) economically reusable, or it can be worn on other occasions if the working environment has different filtering requirements Replace when wearing the mask, without taking it off and fixing it on the flange (20) again.

Best Adhesive

According to the present invention, the adhesive on the wearer's face side of the mask (10) can be applied in any pattern, symmetrical or asymmetrical, such as a dotted or striped pattern. The adhesive is preferably only applied to the flange (20) of the respirator (10), while the filter layer (30) is free of adhesive.

The adhesive is applied in a layer with a thickness c (measured in millimeters (mm)) to one or several areas on the face side of the respiratory mask (10), (hereinafter also referred to as "device"). Preferably all adhesive-applied areas (20) are of constant thickness, but may vary in thickness.

Preferably the thickness of the adhesive layer applied to at least a portion of the face side of the device is constant, or the thickness of the adhesive layer applied along the surface of interest may vary. The adhesive can be applied to the face side of the device by any means known in the industry, such as slot coating, spiral or bead application of printing . Generally speaking, the basis weight of the coated adhesive is between 20g/m ² -2500g/m ² , preferably between 500g/m ² -2000g/m ² , most preferably between 700g/m ² -1500g/m 2 ^m2 , depending on the intended end use.

A detailed analysis of the sequence of occurrences of common conditions from the device to the moment of removal of this type of device shows that the specific characteristics of the adhesive need to be well fulfilled in order for it to achieve the required performance goals, in particular guaranteeing initial fixation, guaranteeing durability during use. Fixation, and painless removal after wearing. The properties considered here are elastic modulus, which describes the elastic behavior of a material, and viscous modulus, which describes the viscous behavior of an adhesive material.

The viscous behavior of the adhesive can be understood as representing the ability of the adhesive to fix quickly and firmly adhere to a specific surface; while the elastic behavior can be understood as representing the "hard" behavior of the adhesive, which is a value for the initial good Sticking is also important. The combination of the two is considered an indicator of the force required to peel. The relationship between the elastic modulus and the viscous modulus is considered an indicator that part of the debonding energy will be dissipated inside the adhesive and part of which is used to trigger the actual debonding.

The relationship between the modulus of elasticity and the modulus of viscosity, as well as their dynamic behavior, are also important in order for the adhesive to have a reliable initial and long-term sticking effect as well as easy and painless release.

The elastic modulus of the adhesive at 37°C (100°F) is abbreviated as G'37; the viscous modulus at 37°C (100°F) is abbreviated as G"37, and at 25°C (77°F) ) is abbreviated as G"25.

Adhesive of the present invention preferably meets the following conditions:

G'37(1rad/sec) between 500Pa-20000Pa, preferably between 700Pa-15000Pa,

The best is between 1000Pa-10000Pa.

G"37(1rad/sec) between 100Pa-15000Pa, preferably between 100Pa-10000Pa,

The best is between 300Pa-5000Pa.

And the ratio of G'37(1rad/sec) to G"37(1 rad/sec) is between 1-30.

As long as the above rheological conditions are satisfied, the adhesive will also satisfy conditions such as sufficient cohesion (to prevent adhesive residue on the skin). This condition is important for the commercial application of this type of adhesive and is well known to those skilled in the art. Any adhesive composition that can meet the above criteria can be used as the device adhesive, as long as it can also meet the common requirements for safety during use on human or animal skin and after the device is discarded.

From a hygienic appearance standard, it is often preferred that such adhesive compositions be clear or white after application.

The thickness of the adhesive layer (or Calliper C, thickness in mm) generally coated on at least a part of the face side of the device, and the viscosity modulus of the adhesive at about 100 rad/sec were measured. G"25. It is related to applying such an adhesive on at least a portion of the facial side of the device and securing the device to the wearer's skin to provide an easy and painless release from the wearer's skin. Correlates with the extent of peeling on the skin.

Therefore, the adhesive layer provided by the present invention preferably has a thickness C such that the viscosity modulus G"25 (100rad/sec) and the thickness C preferably satisfy the following empirical formula:

G”25≤[(7.00+C)×3000]Pa

And preferably the following empirical formula:

G”25≤[(5.50+C)×1700]Pa

Although in the preferred implementation method of the present invention, adhesive layer thickness C is constant, but this kind of adhesive layer also can have different thicknesses on the face side different positions of this device, as long as each position In any case, the above-mentioned relational expression between C and G"25 can be satisfied.

In general, the skin of the person who wears this device is not the same and varies widely. In particular, the type and amount of oil and sebum secreted vary from person to person, and vary greatly. However, it is generally known that the face, especially in the vicinity of the chin, secretes a lot of sebum and that even if some of it is removed, for example by wiping on the corresponding skin area, this sebum is quickly re-secreted. Furthermore, the person wearing the device applies a clearing cream, such as a skin cream, etc., to the area of the skin that is in contact with the adhesive. It is therefore important to provide an adhesive that sticks to oily skin. Therefore the present invention provides a kind of adhesive with dry initial peel strength (PDI) and oily initial peel strength (PGI), the ratio of PDI and PGI measured by test method described herein is at 1: 1-1.0: 0.2 Between, preferably between 1:1-1:0.3. Usually, the adhesive used in this device has a dry initial peel strength (PDI) between 0.1N/cm-7.0N/cm, preferably between 0.1N/cm-5.0N/cm, more preferably between Between 0.5N/cm-3N/cm. The oil initial peel strength (PCI) value is preferably the same as the dry initial peel strength value. However, usually the value obtained is lower, the acceptable range is between 0.1N/cm-5N/cm, preferably between 0.1N/cm-3N/cm, more preferably between 0.1N/cm-2N/cm between. Furthermore, it is best to maintain the adhesion to oily skin for a period of time, so the ratio of oily initial peel strength (PGI) to oily final peel strength (PGF) is between 1:1-1:0.25, preferably between 1:1 and 1:0.25. Between 1:1-1:0.5.

Due to the characteristics and environment in which this type of device is used, the adhesive preferably has a water absorption capacity of at least 3% of the weight of the adhesive as specified in the test (so that the adhesive can be directly pasted on wet or wet skin. superior). In particular, the ratio of the adhesive peel strength measured by the test method here is preferably maintained at a constant value, that is, the ratio of the initial peel strength PDI to the final peel strength PWF is between 2:1-1:4, preferably 2 : between 1.25-2:4, preferably between 2.0:1.5-2.0:2.5. Usually, the initial peel strength of the device should be between 0.1N/cm-7.0N/cm to dry, preferably wet skin, preferably between 0.1N/cm-5.0N/cm, more preferably between Between 0.5N/cm-3.0N/cm.

Furthermore, it is preferred to maintain its peel strength for a period of time even in the presence of water and have a water absorption of less than 15%, preferably less than 10%, more preferably less than 7%. Without intending to be bound by theory, it is believed that in order to be able to stick directly to wet skin and maintain its constant adhesive performance during wear, even when in contact with excess liquid or in high humidity environments, the water absorption capacity of the adhesive needs to be considered question. In particular, it has been determined that not only the absolute water absorption of the adhesive, but also its rate of water absorption must be considered in order for the adhesive to meet the performance parameters given above.

For example, adhesives comprising hydrogel particles known in the art, comprising a three-dimensional rubber matrix and colloidal absorbent particles dispersed within the matrix, can only absorb a limited amount of water through the colloidal particles rather than the matrix. In addition, the speed of water absorption is slow. Therefore, these prior art adhesives cannot stick to wet surfaces.

On the other hand, the hydrogel adhesives in the prior art can not only absorb a large amount of water, but also have a fast water absorption rate, so this type of adhesive can also stick to wet surfaces. However, due to the fast water absorption rate and the large absolute amount of water absorption, the combination of the two causes this type of adhesive to quickly lose its bond strength under excessive water or high humidity conditions.

Correspondingly, the adhesive of the present invention not only exhibits the ability to directly stick to wet skin, but also has the minimum absolute water absorption and a certain water absorption rate, so it can maintain its peel strength within the specified range during wearing.

The adhesive generally has a preferred pattern on the wearer's face side of the device, and the thickness of the adhesive layer is preferably kept constant. The layer is preferably continuous, or discontinuous, ie dotted, spirally or strip-shaped.

Although the adhesive is used on the hairy and mucous tissues of human skin like a pressure sensitive adhesive, it is understood that it is difficult to consider the present adhesive composition to be A typical pressure sensitive adhesive (hereinafter referred to as PSA).

In fact, as known to those of ordinary skill in the adhesive industry, the most characteristic feature that distinguishes PSA from other substances that can temporarily stick objects (such as water between two glass plates) is their rheological parameters, especially The elastic modulus G' changes drastically with the applied stress frequency. More specifically, as noted below, the G' of the PSA increases by several order of magnitude.

Therefore, as a first consequence, it is not possible to determine whether a material can be used as an adhesive by a given rheological parameter value, especially the G' value at a certain fixed frequency. This can be misleading because the absence of other properties, such as surface chemistry, would include materials of no practical value. So it has to be on a kinetic basis. Consideration of rheological properties is necessary. This applies not only to the elastic modulus G', but also to the viscous modulus G", and thus tan(d) = G"/G'.

It is well known that a typical PSA not only has a large variation of G" in the considered frequency range, but also a larger variation of G", and G" can be close to or even higher than the value of G', that is, tan(d) is close to or even greater than 1, especially when the frequency represents the debonding frequency.

Without wishing to be bound by theory, the fact that most of the energy exerted by debonding is dissipated within the adhesive (so that debonding cannot be effectively produced) and at the adhesive and skin interface results in the fact that the visually documented Very high adhesion.

As noted above, the materials used as adhesives in the present invention have rheological properties measured at a reference temperature of 37°C (eg, normal human body temperature) and over a frequency range. It has been found that once the adhesive-bearing device is attached, adhesive contact is formed at low frequencies, while debonding occurs at the speed at which the device is peeled off. The speed is expressed as a frequency of 100 rad/sec, while the low frequency for forming an adhesive bond is 1 rad/sec. Thus according to the invention the frequency range used is between 1-100 rad/sec.

In order to provide good bonding conditions, i.e. at a frequency of about 1rad/sec, the absolute value of the modulus of elasticity should not be too high, otherwise the adhesive will be too hard and will not bond or form tightly to the surface to which it is intended to adhere superior. It is also important to have a small absolute value of G” in order to have good adhesion while the material remains soft and adheres lightly to the skin.

The ratio of G'37 (1 rad/sec) to G'37 (1 rad/sec) is important to ensure that these two values are balanced when applied to the skin.

Importantly, $\frac{G\text{'}37(100\mathrm{rad}/\sec )-G\text{'}\text{'}37(100\mathrm{rad}/\sec )}{G\text{'}37(1\mathrm{rad}/\sec )-G\text{'}\text{'}37(1\mathrm{rad}/\sec )}$ The ratio of must be large enough to ensure that the dynamic behavior of elastic modulus and viscous modulus maintain a relationship that provides strong adhesion and painless and easy peeling.

Finally, those skilled in the art also recognize that the glass transition temperature Tg (glass transition temperature), specific heat capacity, and specific thermal conductivity of an adhesive composition are parameters used to more fully define a class of useful adhesives.

The following set of properties should preferably meet the requirements of the present invention for the adhesive:

$\frac{G\text{'}37(100\mathrm{rad}/\sec )-G\text{'}\text{'}37(100\mathrm{rad}/\sec )}{G\text{'}37(1\mathrm{rad}/\sec )-G\text{'}\text{'}37(1\mathrm{rad}/\sec )}$ The ratio is not less than 0.5, preferably between 0.7-3, most preferably between 1-1.8.

The ratio of G'37/G"37 should not be less than 0.5 at least in the frequency range of 1rad/sec-100rad/sec, the preferred value is between 0.7-10, and the best value is between 1-7.

Rheological behavior is also related to the glass transition temperature Tg value. For the relevant adhesives of the present invention, the Tg value should preferably be lower than 0°C, more preferably lower than -5°C, most preferably lower than -10°C.

Where adhesion and sealing over hairy skin is required, as is often the case when face shields are worn by male wearers, particularly bearded male wearers, the following additional considerations should be made regarding optimal rheological properties of the adhesive.

As previously indicated, the material for which the adhesive of the present invention is used has rheological properties measured at a reference temperature of 37° C. (eg normal human body temperature) and in the range of angular frequencies. It has been found that once the bonded article is applied, adhesive contact is formed at a low frequency, while debonding occurs at the speed at which the article is peeled off. This speed is expressed as a frequency of 100 rad/sec, while the low frequency range for forming an adhesive bond is 1 rad/sec. Thus according to the invention the frequency range used is between 1-100 rad/sec.

In order to provide good bonding conditions, i.e. at a frequency of about 1rad/sec, the absolute value of the elastic modulus G' should not be too high, otherwise the adhesive will be too hard and cannot be tightly bonded or shaped in the desired adhesion on the surface. It is also important to have a small absolute value of G” in order to have good adhesion while the material remains soft and adheres lightly to the skin.

In order to ensure that the hair penetrates the hydrogel adhesive, so that the adhesive can contact and bond to the skin surface, and the hair can be easily separated from the hydrogel adhesive when peeled off without pain or leaving residue, It has now been found that the modulus of elasticity and modulus of viscosity of the adhesive must be within certain absolute values with a minimum Δ.

The following set of properties should satisfy the requirements of the present invention for adhesives:

G'37(1rad/sec) is between 100Pa-4000Pa, preferably between 300Pa-2500Pa,

The best is between 400Pa-1500Pa.

G"37(1rad/sec) is between 100Pa-5000Pa, preferably between 200Pa-2000Pa,

The best is between 300Pa-2000Pa.

G'37(1rad/sec) is at least 50Pa

G”37(1rad/sec) preferably at least 150Pa

Better at least 200Pa

Optimal at least 300 Pa

In addition to ensuring the required initial skin adhesion, and preferably also maintain adhesion during the wearer's entire period, the adhesive peel strength measured according to the test method described in the present invention is in the range of 0.1N/cm-5N/ cm, preferably between 0.2N/cm-3N/cm.

The elastic modulus, viscous modulus and peel strength can be selected within the above ranges depending on the intended end use.

The properties of the hair itself can also affect the ability of the hair to penetrate the hydrogel adhesive. In particular, the thickness, length, thickness and curl of the hair are very important. It has now been found that suitability for a particular hair species embedded within a hydrogel adhesive can be determined by the following formula based on a 1 ^cm2 reference area of hair:

W×C×G’25(1rad/sec)＜24

In the formula:

W = weight (assuming the same specific gravity)

V = volume

C = Curl (ratio of stretched hair length to non-stretched hair length)

Any medically suitable substantially water-insoluble pressure-sensitive adhesive comprising a polymer capable of forming a three-dimensional matrix possessing these properties in order to provide an adhesive composition that meets the aforementioned rheological and physical property requirements for an adhesive agents can be used.

According to the present invention, the three-dimensional matrix, referred to herein as a gel, comprises a chemically or physically crosslinkable polymeric major component. The polymer can be natural or synthetic. Non-crosslinked polymers include repeating units or monomers derived from: vinyl alcohol, vinyl ether and their copolymers, carboxy vinyl monomers, vinyl ester monomers, carboxy vinyl ester monomers, vinyl amide monomers , hydroxy vinyl monomers, cationic vinyl monomers containing amines or quaternary amines, N-vinyllactam monomers, polyethylene oxide, polyvinylpyrrolidone (PVP), polyurethanes, acrylic polymers, such as Methyl acrylate, 2-hydroxyethyl methacrylate, methoxydiethoxyethyl methacrylate and hydroxydiethoxyethyl methacrylate, acrylamide, and sulfonated polymers such as acrylamide sulfonated polymers substances, for example, 2-acrylamidomethylpropanesulfonic acids (AMPs) and (3-sulfopropyl)acrylic acid (SPA), and mixtures thereof. Also, acrylonitrile, methacrylamide, N,N, dimethylacrylamide (NNDMA), acrylates such as methyl, ethyl and butyl acrylate. Alternatively, the non-crosslinked polymer may be a homopolymer or copolymer of polyvinyl ether, or a copolymer derived from a half ester of a maleic ester. Similarly, any other compatible polymer monomer units can be used as copolymers, for example, polyvinyl alcohol and polyacrylic acid or ethylene and vinyl acetate.

As another alternative, the polymer may be a block copolymer thermoplastic elastomer, such as an ABA block copolymer, such as a styrene-olefin-styrene block copolymer or an ethylene-propylene block copolymer. More preferably such polymers include hydrogenated grades of styrene/ethylene-butylene/styrene (SEBS), styrene/isoprene/styrene (SIS) and styrene/ethylene-propylene/styrene (SEPS) .

Particularly preferred polymers are acrylic polymers, sulfonated polymers such as acrylamide sulfonated polymers, vinyl alcohol, vinyl pyrrolidone, polyethylene oxide and mixtures thereof. Most preferred are nitrogen-containing polymers.

According to the invention, the three-dimensional adhesive matrix essentially also contains a plasticizer which is preferably liquid at room temperature. The material is selected such that the polymer is dissolved or dispersed within the plasticizer. For those embodiments employing radiation crosslinking, the plasticizer must also be suitable for radiation crosslinking such that it does not inhibit the radiation crosslinking process of the polymer. The plasticizer can be hydrophilic or hydrophobic.

Suitable plasticizers include: water, alcohols such as glycerol and sorbitol, and polyols such as diols, and ether diols such as mono- or diethers of polyalkylene glycols, mono- or diesters Polyalkylene glycols, polyethylene glycols (usually molecular weight up to about 600), glycolates, glycerol, sorbitan esters, citrates and tartrates, imidazoline-derived amphoteric surfactants, lactams , amides, polyamides, quaternary ammonium compounds, esters such as terephthalate, adipate, stearate, palmitate, sebacate, or myristate and mixtures thereof. Particularly preferred are polyols, polyethylene glycols (molecular weights up to about 600), glycerol, sorbitol, water and mixtures thereof.

Typical adhesives have a polymer to plasticizer ratio (weight/weight) between 1:100 and 100:1, preferably between 50:1 and 1:50. However, the precise amounts and ratios thereof depend largely on the nature of the polymers and plasticizers employed and can be readily selected by those skilled in the art. For example, high molecular weight polymers require much more plasticizer than low molecular weight polymers.

In addition, the binder preferably also comprises micellized lipid polymers, so-called hypercoiling polymers. This polymer acts to micellize and remove built-up oil pockets from the gel-skin interface.

The supercoiled polymers have the ability to more effectively solvate primary surfactant micelles that come into contact with hydrophobic skin soils such as sebum or crème. The result of this functionality is that the bond between the adhesive and the skin is less and less affected by the surfactant or skin fouling capabilities.

The supercoiled polymer preferably comprises any one or combination of the following individual polymers: poly(maleic acid-styrene), poly(maleic acid-butyl vinyl ether), poly(maleic acid-propylene vinyl ether), poly(maleic acid-ethyl vinyl ether) and poly(acrylic acid-ethyl acrylate).

A particularly preferred example is an alternating copolymer of styrene and maleic anhydride. As will be discussed below, the binder seeks to form a biphasic structure when polymerized. These two phases are hydrophilic and hydrophobic. The hydrophobic phase is composed of hydrophobic monomers initially maintained as a homogeneously reacted mixed portion by means of active solvent bridges. Alternatively, the hydrophobic component may also be constituted by a polymer separated from the aqueous phase during the polymerization reaction.

The exact amounts and ratios of supercoiled polymers will depend largely on the nature of these components.

In some cases, the reaction mixture preferably comprises 3%-20% (w/w), most preferably 8%-18% (w/w) of the reaction mixture for providing a stable phase-separated system. polymer dispersion. Such polymers preferably include the following polymers alone or in combination: vinyl acetate-dioctyl maleate copolymer or ethylene-vinyl acetate copolymer. An ethylene-vinyl acetate copolymer such as that available from Harlow Chemical Company under the tradename DM137 is preferred.

The binder preferably also contains a nonionic, cationic, anionic, amphoteric surfactant or any mixture thereof.

Suitable non-reactive nonionic surfactants include, but are not limited to, those selected from higher aliphatic alcohols. (such as fatty alcohol containing about 8-20 carbon atoms, straight chain or branched chain configuration) and about 3-100 moles, preferably about 5-40 moles, and most preferably about 5-20 moles of ethylene oxide Comprehensive product. Examples of such nonionic ethoxylated fatty alcohol surfactants are the Tergitol.TM. 15-S series from Union Carbide and the Brij.TM surfactants from ICI Corporation. Tergitol.TM.15-S series surfactants include C ₁₁ -C ₁₅ secondary alcohol polyglycol ethers. The Brij.TM58 surfactant is polyoxyethylene (20) cetyl ether, and the Brij.TM.76 surfactant is polyoxyethylene (10) stearyl ether.

Other suitable non-reactive nonionic surfactants include, but are not limited to, those selected from 1 mole of alkylphenols containing about 6-12 carbon atoms in a linear or branched configuration with about 3-100 moles of ethylene oxide Polyethylene oxide condensates of alkanes. Examples of nonionic surfactants are the lgepal.TM.CO and CA series from the company Rhone-Poulenc. Igepal.TM.CO surfactants include nonylphenoxypoly(oxyethylene)ethanol. Igepal.TM.CA surfactants include octylphenoxypoly(oxyethylene)ethanol.

Another group of useful non-reactive nonionic surfactants includes, but is not limited to, those block copolymers selected from ethylene oxide and propylene oxide or butylene oxide.

Examples of these nonionic block copolymer surfactants are the Pluronic.TM. and Tetronic.TM. series surfactants from BASF. Pluronic.TM. surfactants include ethylene oxide-propylene oxide block copolymers. Tetronic.TM. surfactants include ethylene oxide-propylene oxide block copolymers. Suitable examples are Pluronic L68 and Tetronic 1307. Particularly suitable examples are Pluronic L64 and Tetronic 1107.

Still other satisfactory non-reactive nonionic surfactants include, but are not limited to, those selected from the group consisting of sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters and polyoxyethylene stearates. Examples of such fatty acid ester nonionic surfactants are Span.TM. and Tween.TM. and Myrj.TM. surfactants from ICI Corporation. Span.TM. surfactants include _C12 - _C18 sorbitan monoesters. Tween.TM. surfactants include poly(oxyethylene) C ₁₂ -C ₁₈ sorbitan monoesters. Myrj.TM. surfactants include poly(oxyethylene) stearates.

Suitable anionic surfactants generally include a hydrophobic moiety selected from about _C6 - _C20 alkyl, alkaryl, and alkenyl groups, and an anionic group selected from sulfate, sulfonate, phosphate, and poly Oxyethylene sulfate, polyoxyethylene sulfonate, polyoxyethylene phosphate and alkali metal, ammonium and tertiary amine salts of such anionic groups.

Anionic surfactants used in the present invention include, but are not limited to, those selected from alkyl or alkaryl sulfates or sulfonates containing about _C6 - _C20 , such as sodium lauryl sulfate (Polystep. -3) and sodium dodecylbenzenesulfonate (Siponate.TM.DS-10 produced by Rhone-Poulene Company); polyoxyethylene (about C ₆ -C ₂₀ ) alkyl or alkylphenol ether sulfate, in The ethylene oxide repeating unit in the surfactant is less than about 30, preferably less than about 20, most preferably less than about 15, such as Polystep.TM.B-1 available from Stepan Company and Polystep.TM.B-1 available from Rhone-Poulene Alipal.TM.EP110 and 115; about C ₆ -C ₂₀ alkyl or alkylphenoxy poly(oxyethylene) ethyl phosphate monoesters and diesters and salts thereof, repeating ethylene oxide in surfactants Units are less than about 30, preferably less than about 20, most preferably less than about 15, such as Gafac.TM.RE-510 and 610 from GAF.

Cationic surfactants used in the present invention include, but are not limited to, those selected from quaternary ammonium salts in which at least one higher molecular weight group and two or three lower molecular weight groups are attached to a common nitrogen atom to form a cation, and The anionic group that plays a charge balancing role is selected from halides (bromide, chloride, etc.), acetate nitrite, and lower alkyl sulfate (methyl sulfate, etc.). The higher molecular weight substituents on the nitrogen atom are usually higher alkyl groups containing about 10-20 carbon atoms, and the lower molecular weight substituents may be lower alkyl groups containing about 1-4 carbon atoms, such as methyl or ethyl, It can sometimes be substituted by hydroxyl. One or more substituents may include an aryl moiety or be substituted with an aryl group such as phenyl or benzyl.

In a particularly preferred example of the present invention, the surfactant comprises at least one propylene oxide/ethylene oxide block copolymer, such as the trade name Pluronic L64 provided by BASFPlc. Desirable reaction mixtures contain 0.1% to 5% (w/w) surfactant of the reaction mixture.

The surfactant acts to degrease the skin and pockets the removed oil within the hydrogel without causing loss of coating adhesion.

Other common additives known in the industry, such as preservatives, antioxidants, pigments, inorganic fillers and mixtures thereof, are also included in the adhesive composition, each in an amount of up to 10% (w/w) each.

According to the invention, in order to be able to form a three-dimensional matrix, the polymer components of the adhesive may be physically or chemically crosslinked. Physical crosslinking means that the polymers are crosslinked not by chemical covalent bonds, but by their physical properties, ie the three-dimensional matrix has regions of high crystallinity, or regions of high glass transition temperature. Chemically crosslinked means that the polymers are crosslinked by chemical bonds. The polymers are preferably chemically crosslinked by irradiation techniques, such as heat, electron beam, ultraviolet, gamma-ray or microwave irradiation.

In addition, when chemical crosslinking is performed in the system, a multifunctional crosslinking agent and/or a free radical initiator may be present in the premix to initiate the crosslinking reaction under irradiation. The amount of this initiator can be up to 5% (weight/weight), preferably 0.02%-2%, most preferably 0.02%-0.2%. Suitable photoinitiators include 1-α-hydroxy ketones and benzil dimethyl ketals, such as Irgacure 651, which are believed to generate benzoyl radicals upon irradiation to initiate polymerization. Such photoinitiators preferably do not carry any substituents in the para position of the aromatic ring. Preferably 1-hydroxycyclohexyl phenyl ketone (available from Ciba Specialty Chemicals Company, trade name Irgacure 184), also preferably Darocur 1173 (2-hydroxyl-2-propyl phenyl ketone) and the combination of Irgacure 184 and Darocur 1173 mixture. In addition, 0.02% to 2% (w/w) thermal initiators can also be used.

The resulting adhesive composition is predominantly hydrophilic. Hydrophobicity and mixed phase composition depend on the nature of the adhesive components. In addition, mixtures of monomers, whether hydrophilic or hydrophilic and hydrophobic, result in a single phase or a mixture of at least two phases. Preferably, the adhesive of the present invention is a mixed phase of hydrophilic and hydrophobic properties.

Monomer mixtures capable of forming one, two or more phases are preferred. Mixed phase adhesives are compositions in which the hydrophobic and hydrophilic components of both the plasticizer and the polymer form two or more separate phases, preferably. In this case, it is best to add an appropriate amount of emulsifier to form a stable emulsion between the incompatible phases.

Without intending to be bound by theory, it is believed that the liquid phase stability of the adhesive after improved peel strength, especially to water, results from the inclusion of hydrophilic, such as polar and/or ionic monomers, preferably A mixture of ionic water-soluble monomers and hydrophobic, ie water-insoluble monomers is obtained. The ratio of hydrophilic monomer to hydrophobic monomer is preferably between 5:1-1:5, preferably between 3:1-1:3, most preferably between 2:1-1:2. The hydrophilicity and hydrophobicity of a monomeric component are always relative to other components. Typically prior art hydrogel adhesives contain only hydrophilic monomers and thus these adhesives have a high rate of water absorption and do not maintain adhesion in the presence of excess liquid. Without intending to be bound by theory, it is believed that the presence of a hydrophobic component in the adhesive matrix reduces the rate at which the adhesive absorbs water. As a result, the adhesive has a more uniform water absorption distribution. In this way, a layer of water film will not be formed between the skin surface and the adhesive. If anything, it prevents the bond from forming between the skin and the adhesive, which in turn reduces the adhesive's ability to bond itself.

Accordingly, the present invention seeks to provide a homogeneously dispersed reaction mixture containing both hydrophobic and hydrophilic components which, during polymerization, separate into a two-phase or multi-phase architecture. The phases have been observed to have a thickness of about 100±50 μm in some instances. The reaction mixture may contain one or more surfactants which assist or promote phase separation but are anisotropically distributed between the phases formed during the course of the polymerization reaction.

In order to promote phase separation more efficiently, the presence of hydrophobic monomers or polymers in the initial homogeneous dispersion is necessary.

The present invention contemplates that phase separated materials contain relatively hydrophobic regions and substantially hydrophilic regions, relatively hydrophobic regions. This enables the polymer to function as a pressure sensitive adhesive, while the substantially hydrophilic regions enable the surfactant to function in an aqueous environment at the interface between the polymer and mammalian skin. When the polymer is placed in contact with the skin, the nature and amount of the surfactant are chosen such that natural or synthetic hydrophobic materials, such as sebum or skin creams, are released from the skin surface and reduced between the hydrophobic microdomains and the skin surface. bonding function between. Since both the polymeric adhesive formed according to the invention and the skin in contact with it are deformable under normal application conditions, an equilibrium interface condition is achieved in which hydrophobic and hydrophobic regions occur on the skin surface. Some space swapping.

Preferred suitable hydrophilic monomers are acrylic acid and its salts, 2-acrylamidomethylpropanesulfonic acid, (3-sulfopropyl)acrylate acid and its salts, and mixtures thereof. A particularly preferred example is 2-acrylamide-2-methylpropanesulfonic acid sodium salt, commonly referred to as NaAMPS, available from Lubrizol as a 50% aqueous solution (reference number: LZ2405) or a 58% solution (reference number: LZ2405A) . Suitable hydrophobic monomer components are methyl, ethyl, n-butyl, hexyl, isooctyl and isodecyl acrylate and methacrylate, vinyl ether, vinylpyrrolidone, glycidyl acrylate and ethoxy acrylate ethyl ethyl ester, tetrahydrofurfuryl acrylate, hydroxypropyl acrylate, vinyl propionate and vinyl butyrate and mixtures thereof. Particularly preferred are ethoxyethyl acrylate or butyl acrylate.

When the adhesive contains a hydrophobic component, such as butyl acrylate, and a hydrophilic monomer (ie, the water-soluble ionic monomer noted above) such as NaAMPS, the presence of a non-ionic water-soluble monomer, such as NNDMA , it acts as a so-called "active solvent bridge" (reactive solvent bridge), so that the components of the seemingly incompatible reaction mixture can be mixed evenly before the polymerization reaction. In this way, the reaction mixture has both hydrophilic groups It is a homogeneous system that contains hydrophobic components and is evenly mixed. When NNDMA is used as a solvent for hydrophilic and hydrophobic substances, a transparent and compatible coating solution or dispersion is formed. Because the active solvent bridge is polymerized , so it is basically removed from the reaction mixture, the system stability is adversely affected, and the compatible coating liquid or dispersion undergoes phase separation, thus forming a two-phase structure.

In a preferred embodiment of the present invention, the above-mentioned non-ionic water-soluble monomer will contain at least one mono- or di-N-alkylacrylamide or their analogs. Herein "analogue" refers to a nonionic water-soluble compound containing an alkyl group or a substituted alkyl group linked to a C=C double bond via an amido or alkylamido group (-CO, NH- or -CO, NR-). monomer. Examples of such analogs include diacetone acrylamide (N-1,1-dimethyl-3-oxobutylacrylamide), N-alkylated acrylamide, N,N-dialkylated acrylamide, N-vinylpyrrolidone and acryloylmorpholine. N, N, dimethylacrylamide (NNDMA) and/or its analogues are preferred. The reaction mixture crude contains from about 15% to 30% (w/w) nonionic water-soluble monomer by weight of the reaction mixture, desirably between about 15% to 25% (w/w).

The "active solvent bridge" used here refers to a partially lipophilic non-ionic water-soluble monomer, which has a certain distribution ability between the hydrophobic phase and the water phase, so that the hydrophobic monomer is basically Dissolved in a homogeneous reaction mixture. The solvent bridge is active, ie it is a polymerizable monomer that participates in the polymerization reaction. Without wishing to be bound by theory, it is believed that the solvent bridging of the nonionic water-soluble monomers is primarily active prior to polymerization or in the early stages of the reaction, with less effect as the polymerization progresses.

When preparing the adhesive composition of the present invention, the components are usually mixed into a homogeneous reaction mixture to form a pregel water-based liquid preparation, which is then converted into a gel by free-radical polymerization, for example, using conventional heat Initiators and/or photoinitiators or by ionizing radiation can be accomplished. Photoinitiation is the preferred method and is usually performed by UV irradiation after coating a pre-gelled reaction mixture containing a suitable photoinitiator on a siliconized release paper or other solid substrate. The intensity of the incident ultraviolet rays in the wavelength range of 240-420 nm is substantially ideally 40 mW/cm ² . Processing is usually carried out under controlled conditions, involving precisely predetermined sequences of mixing and heat treatment.

The time of ultraviolet irradiation should ideally be less than 60 seconds, preferably less than 10 seconds, and more than 95% of the monomers are converted into gels. The ultraviolet irradiation time is shorter than 60 seconds, preferably shorter than 40 seconds, and the conversion rate is higher than 99.95%. Those skilled in the art will appreciate that the level of irradiation will depend on the thickness of the reaction mixture, the concentration of photoinitiator and the nature of the substrate used to coat the reaction mixture, as well as the UV light source.

These irradiation times are for a medium pressure mercury arc lamp UV source operating at 100 W/cm. The measured intensities of ultraviolet rays on the substrate surface at 254 nm and 313 nm are about 150 μW/cm ² and 750 μW/cm ² , respectively. For a given UV lamp, its UV intensity will vary with the operating power and the distance of the reaction mixture from the UV light source.

In order to reduce and preferably eliminate the presence of any residual monomers, it is important to ensure that the reaction is complete. It depends on several factors, such as the substrate on which the adhesive is applied, the type and intensity of UV light, and the amount of UV radiation. The conversion rate of hydrophilic monomers such as NaAMPS should be 98%, preferably 99%, and most preferably 99.9%; such that the amount of monomer in the adhesive is 4600 μg/g or less, preferably 2300 μg/g or less, optimally 230 μg/g or less. The hydrophobic monomer such as NNDMA also has a similar situation, and its conversion rate is 99%, preferably 99.9%, and the best is 99.99%; the amount of monomer in the adhesive is 2200 μ g/g or less, preferably 220 μ g /g or less, preferably 22 μg/g or less.

Thus, the binder is formed by polymerization of a homogeneous aqueous reaction mixture. The reaction mixture comprises a hydrophilic monomer (ie, an ionic water-soluble monomer), a plasticizer (other than water), a non-ionic water-soluble monomer, and water. The amount of hydrophilic monomer is between 5%-50% of reaction mixture weight, preferably between 30%-50%; The weight of plasticizer is between 10%-50% of reaction mixture weight, relatively Preferably between 15%-45%; non-ionic water-soluble monomer up to 50% by weight of the reaction mixture, preferably at 10%-50%, more preferably at 15%-30%, most preferably at 15%- 25%; water up to 40% by weight of the reaction mixture, preferably 0.05%-40%, most optimally 3%-40%. If present, the reaction mixture also includes a surfactant in an amount up to 10% by weight of the reaction mixture, preferably between 0.05% and 9%, most preferably 8%. Similarly, the reaction mixture also contains from 0.1% to 5% by weight of the lipid vesicle gelling polymer, and from 1% to 30% by weight of the reaction mixture of at least one hydrophobic monomer.

The term "homogeneous aqueous reaction mixture" as used herein means a substantially dissolved system in which no phase separation occurs prior to polymerization in the liquid system. For example, emulsions, microemulsions or phase-separated mixtures which are subsequently polymerized are not to be understood as homogeneous aqueous reaction mixtures in the context of the present invention. Therefore special measurements are required to obtain homogeneity when the reaction mixture contains hydrophobic components. This article will explain in more detail.

Surface properties of polymeric materials

According to the present invention, the phase-separated polymeric material contains, at least on its surface, relatively hydrophobic regions and substantially hydrophilic regions, the relatively hydrophobic regions enable the polymer to function as a pressure sensitive adhesive, and the substantially hydrophilic regions Enables the surfactant to function in an aqueous environment at the interface between the polymer and mammalian skin. When the polymer is placed in contact with the skin, the nature and amount of the surfactant is chosen to allow the release of natural or synthetic hydrophobic materials, such as sebum or skin creams, from the skin surface without detrimentally reducing the polymer's ability to absorb water. Adhesive function between aqueous microdomains and skin surface. Since the polymeric adhesive formed by the present invention and the skin in contact with it are deformable under normal application conditions, an equilibrium interface condition is achieved in which hydrophobic and hydrophobic regions will occur on the skin surface. Some space swapping.

Phase-separated polymeric surface materials consist essentially of a distinct hydrophobic phase embedded within a hydrophilic matrix that is predominantly water-containing. The hydrophobic phase is usually elongated, and its lateral dimension is wider than the wavelength of light (eg, 0.5-100 μm). Thus, on samples stained with dyes that bind preferentially to hydrophobic phases, these hydrophobic phases can be visualized under the microscope.

The surface morphology of the elongated hydrophobic phase is variable. Without wishing to be bound by theory, it is believed that the surface tension at the hydrophobic/hydrophilic interface changes as the polymerization progresses, causing its morphology to change in the final polymer. This surface tension can be affected by the active solvent bridge and the nature and amount of surfactant, among other factors.

Therefore, the elongated hydrophobic phases on the surface of the polymeric material may be clustered, or relatively open (open) arrangement. Microscopically hydrophobic phases, eg, appearing as intermittent and/or dendritic strands or closed loops embedded in a hydrophilic matrix.

Typically, polymeric materials are not bicontinuous. At least one of the hydrophobic phase and the hydrophilic phase has a discontinuous region in the polymeric material, and the two phases do not extend to the entire polymeric material at the same time (bicontinuity).

Provided that the thickness c of the adhesive layer applied to at least a portion of the face of the wearer of the device is preferably constant, or may vary across the adhesive-applied surface.

When considering in particular the peeling of adhesive compositions fixed to the wearer's skin, good conditions for peeling of adhesives applied to at least a portion of the wearer's face side of the device have been recognized, i.e. at about 100 rad/ sec frequency, when the adhesive can be easily peeled off from the skin, and especially from the body hair on the part where the device contacts the skin, does not cause pain to the wearer, and thus does not adhere so strongly that it is difficult to peel off from the skin Can only be obtained when stripped from the hair of the wearer. Plus, good release means no adhesive residue on the skin or in the hair.

Typically the thickness C of the adhesive layer on at least a portion of the face side of the device, measured in mm, is related to the amount of sticky film G of the topical adhesive at 25°C at about 100 rad/sec" The relationship between 25 gives an indication of painless and easy peeling of the adhesive from the skin.

Without wishing to be bound by theory, it is believed that higher values for G"25 at 100 rad/sec correspond to higher adhesiveness of the composition, requiring a thicker adhesive layer so that the energy used for peeling is more evenly distributed across the adhesive. In the mixture material, it is transmitted to the skin more smoothly, avoiding the energy peaks that generally cause pain to the wearer. In other words, a thinner adhesive layer must be made with a lower G”25 of the adhesive at 100rad/sec. Pain relief when the device is peeled off.

Test Methods

Peel Adhesive Method

This is a quantitative method of determining the average peel force required to peel the skin at a given peel angle and speed.

equipment

scissors local materials

Standard ruler local materials

The steel pressure roller weighs 5.0kg, has a diameter of 13cm, a width of 4.5cm, and is covered with 0.5mm thick rubber.

Polyester film PET23μ, available from EFFEGIDI S.p.A. 43052, Colorno, Italy

Transfer adhesive 3M 1524, available from 3M Italia S.p.a. 20090 in Segrate, Italy

stopwatch local materials

Tensile testing machine Instron Model 6021 (or equivalent)

test steps

A) Tensile testing machine peel settings:

Load Cell 10N

Test speed 1000mm/min

Distance between fixtures 25mm

Preload 0.2N

Test path "LM" 50mm

Measured variable F mean in "LM" (N)

B) Skin condition and preparation

Samples were peeled from the forearm and tested for three skin conditions:

1) Dry: The forearm was left untreated and was not wiped before the test or between repetitions.

2) Moisture: Add 3ml of distilled water to a cotton disk (Demak'up diameter 5.5cm, weight about 0.6g), and then gently wipe the test site on the forearm three times with the cotton disk. (The forearm test site was a rectangle approximately 2 cm wider and longer than the adhesive area).

3) Oiliness: add 4 drops of NeviaBody (about 0.2g) to a cotton disc (Demak'up diameter 5.5cm, weight about 0.6g), then fold it up to ensure the absorption of Nevia ointment. Dab three swipes (forearm test site is a rectangle approximately 2 cm wider and longer than the adhesive area).

C) Sample preparation

1. Place the sample in an air-conditioned room for about 1 hour (23±2°C, relative humidity 50±2%).

2. Prepare a rectangular adhesive sample (length 260mm±2mm, width 20mm±2mm).

3. Attach polyester film to sample surface (use transfer adhesive to fix polyester to substrate surface).

4. Each test sample needs to be prepared separately and measured immediately.

5. Peel off the release paper from the adhesive, do not touch it. Secure one end to the skin (see part B).

6. Use a steel pressure roller to roll along the adhesive strip for 160mm, once in each direction.

D) Test environment

Adhesives can be tested in two environments:

1) Air-conditioned room as described in C1.

2) Humid environment: After step C4, the sample is placed in a humidity-controlled furnace at 85° C. for 3 hours, and then taken out to carry out steps C5 and C6.

E) perform an action

One minute after step C6, hold the free end of the sample (about 100 mm long) and insert it into the upper end of the adhesion tester, keeping the sample at a 90° angle to the forearm. Start the test machine.

F) report

Record the average value of 5 peel strength tests, and the single value is the basis for calculating the standard deviation between samples.

Residual Monomer Test Method

testing sample

Take 1g hydrogel sample and soak in 100ml 0.9% saline. The samples were placed in brine at 40°C for 24 hours. Aliquots were diluted and subjected to electrospray (LC/MS) analysis.

calibration sample

Dissolve 1 g of a reference monomer (such as NaAMPS) in 1000 ml of 0.9% saline.

Aliquots were diluted and subjected to electrospray LC/MS analysis.

evaluate

Determine the concentration of test samples and calibration samples, and use software such as VGMass Lynx for linear regression analysis.

Example

All formulations described below were coated on polyurethane foam (EV1700x from Caligen). The coating weight is 0.8-1.6kg/m ² , and then irradiated for 10 seconds with a medium-pressure mercury arc lamp operating under ultraviolet light at a power of 100W/cm.

Example 1

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.5g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). Add 30g glycerol and stir for 5 minutes; add 40g NaAMPS (58%) and stir for another 5 minutes. 0.13 g of Solution A was added and finally the whole formulation was stirred for 1 hour before use.

Example 2

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.5g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). Add 10g Mowilith DM137 (50% ethylene-vinyl acetate copolymer dispersion in water, produced by Harco) and stir for 5 minutes, then add 30g glycerol and stir for 5 minutes, then add 40g NaAMPS (58%), and stir again 5 minutes. 0.13 g of Solution A was added and finally the whole formulation was stirred for 1 hour before use.

Example 3

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.5g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). Add 10g Mowilith DM137 (50% ethylene-vinyl acetate copolymer dispersion in water, produced by Harco) and stir for 5 minutes, then add 30g glycerol and stir for 5 minutes, then add 40g NaAMPS (58%), and stir again 5 minutes. Add 0.5 g of Pluronic L64 (poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) block copolymer, available from BASF). 0.13 g of Solution A was added and finally the whole formulation was stirred for 1 hour before use.

Example 4

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.4g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). Add 2 g of Mowilith DM137 (50% dispersion of ethylene-vinyl acetate copolymer in water, manufactured by Harco) and stir for 5 minutes. An additional 36 g of glycerol was added and stirred for 5 minutes, followed by 40.36 g of NaAMPS (58%) and stirred for an additional 5 minutes. Add 0.25 g of Pluronic L64 (poly(ethylene glycol)-poly(propylene glycol)-polyethylene glycol) block copolymer, available from BASF). Add 0.8 g of 30% poly(styrene-maleic acid copolymer) in sodium salt solution (Aldrich) and stir for 10 minutes. Add 0.13 g of Solution A and finally stir the entire formulation for 1 hour before use.

Example 5

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.4g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid). To this was added 10 g of Mowilith DM137 (a dispersion of 50% ethylene-vinyl acetate copolymer in water, produced by Harco) and stirred for 5 minutes. Add 36g of glycerol and stir for 5 minutes, then add 40.36g of NaAMPS (58%) and stir for another 5 minutes. Add 0.25 g of Pluronic L64 (poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) block copolymer, available from BASF), to which add 0.8 g of 30% poly(styrene-maleic acid) Aqueous solution of alternating copolymer sodium salt (Aldrich) was stirred for 10 minutes. 0.13 g of solution A was added and the whole preparation was finally stirred for 1 hour before use.

Example 6

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.4g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). To this was added 10 g of Mowilith DM137 (a dispersion of 50% ethylene-vinyl acetate copolymer in water, produced by Harco) and stirred for 5 minutes. Add 36g glycerol, stir for 5 minutes, add 40.36g NaAMPS (58%), and stir for 5 minutes; add 0.5g Pluronic L64 (poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) embedded Segment copolymer, available from BASF), add 0.8g 30% poly(styrene-maleic acid) alternating copolymer sodium salt aqueous solution (produced by Aldrich), and stir for 10 minutes. 0.13 g of Solution A was added and finally the whole formulation was stirred for 1 hour before use. Optical contrast microscopy revealed that the resulting gel had a normal phase-separated surface (see Figure 1).

Example 7

Mix 6.0g Irgacure 184 with 20g IRR280 (PEG400 diacrylate, produced by UCB) (solution A). Add 23.4g NNDMA to 0.07g Irgacure 184, stir for 1 hour, (cover the container to avoid light). 20 g of Mowilith DM137 (50% dispersion of ethylene-vinyl acetate copolymer in water, manufactured by Harco) was added and stirred for 5 minutes. Add 36g glycerol, stir for 5 minutes, add 40.36g NaAMPS (58%), and stir for 5 minutes; add 0.5g Pluronic L64 (poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) embedded Segment copolymer, available from BASF), add 0.8g 30% poly(styrene-maleic acid) alternating copolymer sodium salt aqueous solution (produced by Aldrich), and stir for 10 minutes. 0.13 g of Solution A was added and finally the whole formulation was stirred for 1 hour before use.

Example 8

Add 40.4 parts of 58% sodium 2-acrylamido-2-methylpropanesulfonate solution (NaAMPS) (LZ2405A) and 0.5 parts of Pluronic LF64 (BASF) to part of the glycerin, and stir the solution until it is evenly mixed. Add 0.13 part of solution in this solution, this solution contains 20 parts of polyethylene glycol diacrylate (PEG600) (produced by chemical company, trade name is Ebacryl 11), wherein 6 parts of 1-hydroxycyclohexyl phenyl ketone (Ciba Produced by the company, the trade name is Irgacure 184) has been dissolved in it. A promising solution containing 8 parts of butyl acrylate and 15.7 parts of N,N dimethylacrylamide (Kohjin) was added to the reaction mixture. As in Example 1, the solution was finally cured by UV radiation. Optical contrast microscopy revealed that the resulting gel had a normal phase-separated surface and enhanced adhesion to skin previously treated with Nevia skin cream (see Figure 2).

Example 9

To 30 parts of glycerol, add 0.5 parts of 30% poly(styrene-maleic acid) alternating copolymer sodium salt solution (produced by Aldrich) and 40 parts of 58% 2-acrylamido-2-methylpropanesulfonate sodium solution (NaAMPS) (LZ2405A) and 0.5 parts of Pluronic P65 (BASF), the solution was stirred until uniformly mixed. Add 0.13 parts of solution in this solution, this solution contains 20 parts of polyethylene glycol diacrylate (PEG600) (produced by UCB chemical company, trade name is Ebycryl 11), wherein 6 parts of 1-hydroxycyclohexyl phenyl ketone ( Produced by Ciba Company, trade name is Irgacure 184) has been dissolved in it. To the reaction mixture was added 6 parts of ethoxyethyl acrylate and 18 parts of N,N dimethylacrylamide (Kohjin). As in Example 5, the solution was finally cured by UV radiation. Optical contrast microscopy revealed that the resulting gel had a normal phase-separated surface (see Figure 7 and the related Discussion section below).

result Subject 1 subject 2 Example Dry (PDI) Oily (PGI) Dry (PDI) Oily (PGI) 1min 10min 1min 10min 1 1.75 0.13 - 1.57 0.19 - 2 2.96 0.16 - 3.18 0.44 - 3 2.81 0.52 0.33 2.46 0.67 0.61 4 0.81 0.15 0.26 0.96 0.29 0.47 5 1.2 0.52 0.69 2.2 0.83 0.88 6 1.6 0.45 0.6 2.2 0.64 0.56 7 1.2 0.49 0.62 1.6 0.74 0.88

microscope

The gels of Examples 6, 8, and 9 were observed with a Leitg Dialux 20 microscope with a "Wild MPS Photoautomat" camera attachment. A 12.5x eyepiece is mounted on the microscope. Images are magnified through a set of objectives, typically 4x, 10x (Phaco) and 25x (Phaco), using objectives with phase contrast and brightfield illumination.

dyeing

The sample of Example 9 was stained before microscopic observation. Hydrophobic differential regions of the hydrogel surface were stained using a saturated solution of bromopyrogallol red in methanol. This solution was applied to the sample surface, and excess dye solution, as well as solid dye, was washed away with methanol.

The following are the criteria for choosing dyes.

The choice of stain to differentially stain the more hydrophobic or more hydrophilic regions of these gels was influenced by several factors, as illustrated by a comparison of bromopyrogallol red with sodium fluorescein, both of which Dyes are taken up or retained in different polymers to varying degrees. The two main factors are charge and hydrophobicity. Bromopyrogallol red mainly contains acidic -SO ₃ H and -COOH groups, while fluorescein sodium mainly contains slightly acidic -COOH groups. The basic region of the polymer has the greatest affinity for acid dyes, while the acidic region has a slightly weaker affinity for acid dyes. It can also be observed that the higher the moisture content of the material, the faster the dye will be absorbed. In the case of ordinary hydrogels, the higher the water content of the material, it often contains slightly basic N-vinylpyrrolidone or N, N-dimethylacrylamide groups, which can attract acidic groups such as -SO ₃ H and -COOH groups.

In addition to the acidity and basicity of the dye and the polymer, the partition coefficient of the dye also has a significant impact on the retention of the dye in the material. This property can be characterized by conventional common measurement methods, such as measuring the partition coefficient (KOW) of the dye between octanol and water. The logKOW of bromopyrogallol red=-0.49 and that of sodium luciferin=-0.98. Both dyes are capable of partitioning between the aqueous and non-aqueous components of the polymer used.

However, bromopyrogallol red may be more hydrophilic and more hydrophobic than the more hydrophilic environment of sodium luciferin. This preference can be illustrated by the fact that common N-vinylpyrrolidone or N,N-dimesoacrylamide based hydrogels readily occlude about 30% bromopyrogallol within the polymeric network red.

Bromopyrogallol red has a higher affinity for hydrophobic regions resulting in a darker color, and its solubility in methanol makes it more suitable than sodium fluorescein for differential staining of hydrophobic and hydrophilic regions on the surface of polymer gels. the existence of the area.

Overlay

The adhesive present on the face side of the face mask (10) before use is preferably covered with a cover layer, such as at least one release sheet (40) or paper, such as siliconized paper.

In accordance with the present invention, it has been found advantageous to provide at least two release sheets (40) for the wearer's respiratory appliance.

Preferably such release tabs (40) extend from the outer edge (24) of the flange (20) to the filter layer (30), preferably to the midpoint of the mask (10). Such an embodiment may allow peeling of the release sheet (40) to begin at the center rather than from the outer edge of the mask (10).

In a preferred embodiment of the present invention, the release sheet (40) is provided with straight sides, preferably parallel to the longitudinal axis of the mask. This embodiment is shown in FIG. 3 .

It is also preferred that the release sheets (40) are provided with a cover layer superimposed such that at least a portion of at least one release sheet is not in contact with the adhesive, facilitating easier release. The outer profile of the release sheet (40) can take the same shape as the outer edge (24) of the flange (20), or it can take other shapes that are convenient for production.

It has been found that the mask (10) provided in accordance with the present invention fits best if the adhesive contact of the flange (20) is first formed in the wearer's nose and chin area, and then in the cheek and corner of the mouth area. comfortable. This facilitates symmetrical application of the mask (10), whereby the longitudinal axis of the mask (10) coincides with the axis of symmetry of the wearer's face. In the preferred embodiment, there are at least two release sheets for the wearer to apply the mask (10) as described above.

As disclosed herein, the cover provided by at least two release sheets (40) is very beneficial when used in a mask (10). Such coverings may also be used in other devices intended to cover the wearer's respiratory organs. Such appliances include anti-snoring devices such as disclosed in pending EPO patent application 00120457.7 (Attorney Docket No. CM 2409 FQ).

Claims (12)

1. A breathing mask (10) comprising a flange (20) and an air control module (30), said flange (20) having an inner edge (22) and an outer edge (24), and said Between the inner edge (22) and the outer edge (24), the first width and the second width measured at a place perpendicular to the inner edge (22), are characterized in that: the first width is greater than the second width. 2. Respiratory mask (10) according to claim 1, characterized in that the first width is at least 10% larger than the second width. 3. Respiratory mask (10) according to any one of the preceding claims, characterized in that said first width is measured at the middle of the nose (26) and/or the middle of the chin (29). 4. Respiratory mask (10) according to any one of the preceding claims, characterized in that said second width is measured at the cheeks (27) and/or mouth corners (28). 5. The breathing mask (10) according to any one of the preceding claims, characterized in that said air control module (30) is provided with stretching means (32). 6. The breathing mask (10) according to any one of the preceding claims, wherein said flange comprises one side of the wearer's face and the outside, characterized in that: one side of the wearer's face of said flange (20) There is an adhesive layer. 7. The breathing mask (10) according to claim 6, characterized in that: the adhesive is a hydrogel adhesive. 8. The respiratory mask (10) of claim 7, wherein the adhesive is a substantially water-insoluble pressure-sensitive adhesive comprising a polymer forming a three-dimensional matrix, and Contains less than 10%, preferably less than 5% of hydrogel particles by weight of the binder. 9. The breathing mask (10) according to claim 7, characterized in that: the adhesive comprises: - a polymer selected from acrylic polymers, sulfonated polymers, vinyl alcohol, vinyl pyrrolidine, polyethylene oxide or mixtures thereof, and - a plasticizer selected from polyols, polyethylene glycol, sorbitol, water or mixtures thereof. 10. A device for controlling the inhalation of air, such as an artificial respirator, comprising a breathing mask (10) according to any one of the preceding claims. 11. A device for analyzing exhaled air, such as a breathalyzer, comprising a breathing mask (10) according to any one of the preceding claims. 12. A device (10) covering the respiratory organs of a wearer, said device having a wearer's face side and an outside, said wearer's face side comprising a plurality of continuous adhesive layers, characterized in that each of said continuous The adhesive layer is covered with at least two release sheets (40).

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