JPH0532535A - Coating film type skin protecting agent - Google Patents

Abstract

PURPOSE:To obtain a skin protecting agent capable of forming a thin transparent coating film, having good feeling in use, excellent water resistance, readily washable with alkali soap. CONSTITUTION:A coating film type skin protecting agent substantially comprising (a) about 1-3 pts.wt. copolymer of methyl methacrylate and methacrylic acid in a ratio of 2:1, (b) about 0.05-0.6 pt.wt. terpolymer of ethyl acrylate, methyl methacrylate and methacryloyloxyethyl trimethylammonium chloride in a ratio of 1:2:0.1 and (c) the rest of a hydrous alcohol.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin protectant capable of forming a water-resistant and alkali-soluble film by combining known acrylic copolymers.

[0002]

2. Description of the Related Art It has been quite a while since many hand rashes such as housewife's eczema occurred among skin diseases, and it has been a problem for a long time, but the number is still declining. . This disease occurs as a result of the excessive removal of sebum from the skin by a household detergent with strong degreasing power, such as a kitchen neutral detergent, making it more susceptible to external irritation,
In hair profession, mechanic, profession such as farming, hair dye,
It is caused by frequent contact with skin-toxic substances such as machine oil and pesticides.

Topical steroids for the treatment of this disease,
Replenishment of oils, use of sebum secretagogues, use of external preparations containing moisturizers, replenishment of skin constituents and the like are performed. Also,
As a preventive measure, in order to prevent contact with detergents and other harmful substances, rubber or vinyl gloves are worn during cooking and washing, and a film-forming type skin protectant is used instead.

In particular, the film-forming type skin protectant is intended to form a film by applying or spraying on the skin surface to protect the skin. Heretofore, as film-forming type skin protectants, those using a silicone base, those dissolving a cellulose derivative in a strong organic solvent, and those using a novel acrylic polymer have been known. When a silicon-based base was used, film formation was not sufficient, and there were problems such as stickiness during application and easy removal from the skin surface by water and oil. When a cellulose derivative is used, there are problems that the solvent such as acetone and ethyl acetate irritates the skin and mucous membranes, or it is not easy to remove the formed film from the skin. Acrylic copolymers, which have been conventionally used as film coating bases for pharmaceuticals and are known to have high safety, have recently been applied to the skin as the main base of film-type external preparation compositions (JP 3-77820,
JP-A-3-128316) has been proposed. However, in all cases, the characteristics of the coating are defined mainly for the purpose of promoting or controlling the percutaneous absorption of the active ingredient, and therefore, when these are used as skin-protecting agents of the film-forming type, the film strength against neutral detergent is unsatisfactory. It was not suitable for use as a film-forming type skin protector because it was sufficient and was inferior in water resistance and usability. However, recently, a new acrylic copolymer (Japanese Patent Publication No. 2-9006) in which the drawbacks of known acrylic polymers as the base material for the above-mentioned applications are improved has been proposed, but it is still not sufficient.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have found that the following properties are desired for a film-type skin protectant: 1) A thin and transparent film can be formed. 2) It has water resistance and can be easily applied from the skin surface with an alkaline soap. 3) Make a stretchable film and adhere to the skin 4) Have little odor and irritation 5) Do not penetrate neutral detergent 6) Dissolve in alcohol or hydrous alcohol 7) Breathability and It has water vapor permeability, does not get sticky during coating, does not get sticky, and does not feel slippery. 8) As a result of intensive research, we focused on the fact that it dries in a relatively short time after application. It is used as a base, and by combining known acrylic copolymers that are highly safe but unsuitable for skin protectants, the above properties desired as skin protectants can be obtained. The present invention has been completed by finding that it can be exerted.

[0006]

Means for Solving the Problems That is, the present invention comprises: a) about 1 to 3 parts of a 2: 1 copolymer of methyl methacrylate and methacrylic acid b) ethyl acrylate, methyl methacrylate and meta 1: with trimethylammonium ethyl acrylate
A copolymer of 2: 0.1 and / or a copolymer of 1: 2: 0.2 about 0.05 to 0.6 parts c) A film-type skin protectant having a basic composition of residual amount of hydrous alcohol. And more preferably, a) about 2 to 1 part of a 2: 1 copolymer of methyl methacrylate and methacrylic acid a ') 1: 1 of methyl methacrylate and methacrylic acid.
About 6 parts or less (however, the sum of the copolymers of a) and a ') is about 1 to 7 parts) b) of ethyl acrylate, methyl methacrylate and trimethylammonium ethyl methacrylate. 1:
2: 0.1 copolymer and / or 1: 2: 0.2 copolymer about 0.05 to 0.6 parts c) A film-type skin protectant having a basic composition of residual amount of hydrous alcohol. .

[0007]

The skin protective agent of the present invention forms a hydrophobic colorless transparent thin film in a short time when applied to the skin, has breathability and water vapor permeability, and is a stimulant from the outside for a long time. On the other hand, it has the property of protecting the skin and being able to be easily washed off with an alkaline soap when removing the film.

The copolymers a), a ') and b) used in the present invention are all known and have been widely used as a film coating base for pharmaceuticals. The copolymers a) and a ') both have an average molecular weight of about 13.5.
Since it is soluble in water at pH 7 or higher and pH 6 or higher, it is a polymer compound conventionally used as an enteric base. The copolymer b) has an average molecular weight of about 150,000, is pH-independent and is insoluble in water, and is therefore a polymer compound conventionally used as a sustained-release base. In each of the above-mentioned copolymers, a) is Eudragit S, for example, S100, a ') from Germany's Röhm Pharma GmbH, Eudragit L, for example, L100, b) is Eudragit RS, for example, RS100, RSPM, RS10
It is marketed under the trade name of 0L, RSPML and the like.

Of the above-mentioned components, the copolymer of a),
The copolymer of b) and hydrous alcohol are essential components.
When the amount of the copolymer a) is small, the film strength is insufficient and the film is easily peeled off from the skin. In the skin protectant of (1), about 1 to 3 parts is suitable. By blending the copolymer of b), the strength or permeability of the coating can be adjusted, but if the blending amount is too small, the coating will be too thin to peel off easily from the skin, and if too large, it will adhere strongly to the skin. Since it cannot be easily removed with an alkaline soap, a blending amount of about 0.05 to 0.6 part is suitable, and a blending amount of about 0.1 to 0.2 part is particularly preferable. The blending ratio of the copolymer of b) to the copolymer of a) is about 1/60 to 3/5.

Examples of the alcohol used in the skin protectant of the present invention include ethanol and isopropanol. These may be used alone or in combination. In order to adjust the drying time at the time of applying the skin protectant of the present invention, water can be added to make a hydroalcoholic solution, but the amount of water is preferably about 1 to 30% with respect to the skin protectant. Is.

In order to further improve the feeling of use of the skin protectant of the present invention (transparency of coating, smooth feeling, etc.) and to facilitate removal of the coating with an alkaline soap, the above a ') is added in addition to the above essential components. Can be blended. in this case,
The blending amount of the copolymer of a ') above is appropriately about 6 parts or less for the skin protecting agent alone, but in order to prevent the skin from feeling tingling and whitening, It is suitable to make the total amount of compounding about 1 to 7 parts.

If desired, the skin protectant of the present invention may contain a cellulose derivative or a plasticizer. Examples of the cellulose derivative include ethyl cellulose, hydroxypropyl cellulose, methyl cellulose, hydroxypropyl methyl cellulose and the like, with ethyl cellulose and hydroxypropyl cellulose being particularly preferable. The cellulose derivative is useful for preventing the coating film from spreading to a part other than the necessary part when applying the skin protectant, and the compounding amount thereof is about 2 parts or less, preferably about 0.4 to 0.8 part. Is.
Examples of the plasticizer include triethyl citrate, polyethylene glycol, diethyl phthalate, 1,3-butylene glycol, dipropylene glycol and triacetin, and these may be blended alone or in combination. Of the above plasticizers, especially triethyl citrate, 1,3
-Butylene glycol is preferred. The thickness of the formed film can be adjusted by these plasticizers, and the amount thereof is about 15 parts or less, preferably about 3 to 10 parts.

Further, if desired, the skin protective agent of the present invention may include a medicinal ingredient preferable for skin, such as γ-oryzanol, tocopherol acetate, glycyrrhetinic acid, etc. which are used in external medicines, quasi drugs or cosmetics. You may further mix.

The known acrylic copolymer used in the skin protectant of the present invention, that is, the above a),
The prior art in which a ') and b) are combined to form a film has been proposed as a "drug-release controlling film for sustained-release preparations" in the field of film coating of drugs (JP-A-3-72).
No. 38). However, in this case, the blending ratio of the copolymer of b) is about 1.5 to the copolymer mixture of a) and a ').
It is as high as 5.7 times, which is significantly different from the same mixing ratio of the present invention of about 0.6 times or less. The properties of the proposed composition (Comparative Examples 6 and 7) as a skin protectant were confirmed, but it was shown that the composition strongly adheres to the skin and cannot be easily removed with an alkaline soap. It turned out to be unsuitable for the use of skin protectants.

[0015]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 20 parts of purified water was added to 3 parts of triethyl citrate, and 50 parts of isopropanol was further mixed, and then, 1.5 parts of Eudragit S100, 1.5 parts of L100 and RS100.
L to 0.1 part and hydroxypropylcellulose to 0.
Dissolve 6 parts sequentially and make up to the total amount with isopropanol.

Example 2 10 parts of purified water was added to 50 parts of isopropanol, 1 part of Eudragit S100 and 0.5 part of RSPML were sequentially dissolved, and isopropanol was added to the total amount.

Example 3 To 0.5 part of triethyl citrate, 20 parts of ethanol was added, and further 50 parts of isopropanol were mixed, 1.5 parts of Eudragit S100 and 1.5 parts of L100,
0.5 parts of RSPML and 2 parts of 1,3-butylene glycol are sequentially dissolved and mixed, and the total amount is made up with isopropanol.

Example 4 20 parts of purified water was added to 50 parts of isopropanol, 1.5 parts of Eudragit S100 and 1.5 parts of L100.
Parts and RSPML are sequentially dissolved in 0.1 part, and the total amount is made up with isopropanol.

Example 5 To 3 parts of triethyl citrate was added 20 parts of purified water, and 50 parts of isopropanol was further mixed. Then, 1.5 parts of Eudragit S100, 1.5 parts of L100 and RSPML were mixed.
0.1 part is sequentially dissolved, and the total amount is made up with isopropanol.

Example 6 To 5 parts of triethyl citrate was added 30 parts of purified water, and 50 parts of isopropanol was further mixed, and 1 part of Eudragit S100, 6 parts of L100 and 0.1 parts of RS100 were mixed.
Parts and 0.1 parts of ethyl cellulose are sequentially dissolved, and the total amount is made up with isopropanol.

Example 7 To 3 parts of triethyl citrate was added 20 parts of purified water, and 50 parts of isopropanol was further mixed. 3 parts of Eudragit S100, 0.2 part of RS100L and 0.6 part of hydroxypropyl cellulose were mixed. Dissolve in order and make up to the total volume with isopropanol.

Example 8 To 3 parts of triethyl citrate was added 20 parts of purified water, and 50 parts of isopropanol was further mixed, and then, 3 parts of Eudragit S100, 0.2 part of RS100 and 0.6 part of hydroxypropyl cellulose were mixed. Dissolve in order and make up to the total volume with isopropanol.

Example 9 20 parts of purified water was added to 3 parts of triethyl citrate, and 50 parts of isopropanol was further mixed, 3 parts of Eudragit S100, 0.3 part of RS100, 0.3 part of RSPML and hydroxy. 0.6 parts of propylcellulose are sequentially dissolved, and the total amount is made up with isopropanol.

Example 10 To 8 parts of triethyl citrate, 28 parts of ethanol was added, and further 50 parts of isopropanol were mixed, 1.5 parts of Eudragit S100, 1.5 parts of L100 and RSP were mixed.
0.1 part of ML and 0.
6 parts and 0.5 part of γ-oryzanol are sequentially dissolved, and the total amount is made up with isopropanol.

Comparative Example 1 To 1.5 parts of diethyl phthalate, 20 parts of purified water was added, and 50 parts of isopropanol was further mixed. Then, 3 parts of Eudragit S100 and 1 part of hydroxypropylcellulose were sequentially dissolved, and isopropanol was added to the whole amount. And

COMPARATIVE EXAMPLE 2 4 parts of Eudragit L100 and 0.6 parts of hydroxypropylcellulose were sequentially dissolved in 3 parts of triethyl citrate and 20 parts of purified water and 50 parts of isopropanol, and the total amount was added with isopropanol. And

Comparative Example 3 20 parts of purified water was added to 3 parts of triethyl citrate, and 50 parts of isopropanol was further mixed. Then, 1.5 parts of Eudragit S100, 1.5 parts of L100 and 0.1 parts of hydroxypropyl cellulose were added. Dissolve 6 parts sequentially and make up to the total amount with isopropanol.

Comparative Example 4 3 parts of triethyl citrate was added with 20 parts of purified water, and 50 parts of isopropanol was further mixed, and then, 3 parts of Eudragit L100, 0.1 part of RSPML and 0.6 part of hydroxypropyl cellulose were mixed. Dissolve in order and make up to the total volume with isopropanol.

Comparative Example 5 3 parts of triethyl citrate was added with 20 parts of purified water, and 50 parts of isopropanol was further mixed. 3 parts of Eudragit L100, 0.1 part of RS100 and 0.6 part of hydroxypropyl cellulose were added. Dissolve in order and make up to the total volume with isopropanol.

Comparative Example 6 20 parts of purified water was added to 3 parts of triethyl citrate, and 50 parts of isopropanol was further mixed, and then 1.5 parts of Eudragit S100, 1.5 parts of L100 and RS10.
4.5 parts of 0 are sequentially dissolved, and the total amount is made up with isopropanol.

COMPARATIVE EXAMPLE 7 20 parts of purified water was added to 3 parts of triethyl citrate, and 50 parts of isopropanol was further mixed, 0.5 parts of Eudragit S100, 0.5 parts of L100 and RS100 were mixed.
1 part of L, 3 parts of RS100 and 0.6 parts of hydroxypropylcellulose are sequentially dissolved, and the total amount is made up with isopropanol.

Comparative Example 8 1 part of Eudragit L100 was added to 60 parts of ethanol to dissolve, and a mixed solution of 37 parts of purified water and 1 part of isopropanol was added to this solution and stirred until a uniform solution was obtained.

[0034]

To confirm the characteristics of the film-type skin protectant of the present invention, a composition not containing a known acrylic copolymer which is an essential component of the present invention and a known acrylic copolymer having a different blending ratio from the present invention are used. The following tests were carried out with a representative composition of the prior art relating to the polymer combination as a control.

Specimens: Compositions of Examples 1 to 10 (skin protectant compositions of the present invention) Compositions of Comparative Examples 1 to 3 (compositions containing no copolymer of the above b)) Comparative Examples 4 and 5 (Composition containing no copolymer of the above a)) Compositions of Comparative Examples 6 and 7 (Representative compositions of JP-A-3-7238) Compositions of Comparative Example 8 (JP-A-3-77820) Representative composition of No.)

Test Example 1 (Sensory Test) Each of the above samples was applied to the back of a human hand, and a sensory test was conducted on the adhesiveness and tackiness at the time of application and the adhesiveness after drying, transparency, elongation, and feeling of smoothness. The results are shown in Table 1.

Test Example 2 (Washing test) A 1% aqueous solution of sodium copper chlorophyllin as a dye is applied to the back of a hand, and after drying, each of the above samples is applied.
After drying, it was washed with an alkaline soap to visually confirm from the remaining amount of the dye whether or not the coating was removed, and the results are shown in Table 1.

Test Example 3 (Film Strength Test) Each of the above specimens was placed in a hermetically sealed container and had a diameter of 17 m.
After putting a glass ball of m into the surface of the glass, the surface of the glass ball was sufficiently wet and then air-dried at room temperature. A test solution (pH about 7.7) prepared by adding 5 ml of kitchen neutral detergent to 900 ml of purified water is injected into a disintegration tester with an auxiliary plate (described in the disintegration test method of the Japanese Pharmacopoeia),
After putting the above coated glass beads and moving up and down for 20 minutes, the glass beads are taken out and the state of coating is visually confirmed. The results are shown in Table 1.

[0039]

[Table 1]

As a result of the above-mentioned tests, the skin protectant of the present invention had a sensory characteristic and a medium level as compared with the compositions of Comparative Examples 1 to 5 which did not contain the copolymer a) and / or the copolymer b). It was clearly superior in terms of film strength against a mild detergent. Also, b)
In comparison with the representative compositions (Comparative Examples 6 and 7) of the oral film coating (Japanese Patent Application Laid-Open No. 3-7238) in which the proportion of the copolymer is large, the removal of the coating with the alkaline soap was extremely easy. It was clearly excellent. Further, it was clearly superior in the film strength to a neutral detergent as compared with the representative film composition (Comparative Example 8) in which the active ingredient of the film-type external preparation (JP-A-3-77820) was removed.

As described above, the skin protectant of the present invention is thin and has a feeling of use when it is combined by limiting the proportion of known acrylic copolymers, which have been conventionally unsuitable for forming a film for skin protection. Good, does not penetrate neutral detergent,
It has come to exhibit unexpectedly good film properties for skin protection such as excellent water resistance and easy cleaning with alkaline soap. Therefore, the skin protectant of the present invention can be used as an adjunct to the prevention or treatment of hand eczema for housewives at home, professional equipment cleaners, or users of liquid medicine.

Claims (8)

[Claims] 1. A film-type skin protectant essentially consisting of the following basic components. a) about 2 to 1 part of a 2: 1 copolymer of methyl methacrylate and methacrylic acid b) 1: 1 of ethyl acrylate, methyl methacrylate and trimethylammonium ethyl methacrylate.
2: 0.1 copolymer and / or 1: 2: 0.2 copolymer about 0.05 to 0.6 parts c) hydrous alcohol residual amount 2. The copolymer of a) has an average molecular weight of about 13.5.
The skin protectant according to claim 1, which is soluble in water having a pH of 7 or more. 3. The skin protectant according to claim 1, wherein the copolymer b) has an average molecular weight of about 150,000, is pH-independent and is insoluble in water. 4. The skin protective agent according to claim 1, wherein the alcohol is ethanol or isopropanol. 5. A film-type skin protectant essentially consisting of the following basic components. a) 2: 1 copolymer of methyl methacrylate and methacrylic acid about 1-3 parts a ') 1: 1 of methyl methacrylate and methacrylic acid
About 6 parts or less (however, the sum of the copolymers of a) and a ') is about 1 to 7 parts) b) of ethyl acrylate, methyl methacrylate and trimethylammonium ethyl methacrylate. 1:
2: 0.1 copolymer and / or 1: 2: 0.2 copolymer about 0.05 to 0.6 parts c) hydrous alcohol residual amount 6. The skin protectant according to claim 5, wherein both the copolymers a) and a ′) have an average molecular weight of about 135,000 and are soluble in water having a pH of 7 or more. 7. The skin protectant according to claim 5, wherein the copolymer of b) has an average molecular weight of about 150,000, is pH-independent, and is insoluble in water. 8. The skin protective agent according to claim 5, wherein the alcohol is ethanol or isopropanol.