JPH0797317A - Film-forming agent for external use - Google Patents

Abstract

PURPOSE:To obtain a safe film-forming external agent quickly drying to form a water-soluble coating film free from tackiness and keeping the coating film even in the presence of water or sweat by using an N-vinylacetamide polymer or its copolymer essentially as the film-forming resin. CONSTITUTION:This external agent composition contains a homopolymer or copolymer of N-vinylacetamide as a film-forming resin to give a water-soluble coating film and is useful for cosmetic, external medicine, exterior skin material, quasi-drug, etc. The N-vinylacetamide polymer is preferably a copolymer of N-vinylacetamide and one or more kinds of ethylenic monomers of the formula {R1 is H or methyl; X is COOM [M is alkali metal or COOCnH2n+1 ((n) is 0-8), etc.]} and containing the ethylenic monomers and the N-vinylacetamide in an amount of >=50% of the total monomer. A coating film can be formed on the skin or mucosa by applying the film-forming external agent to the skin, etc., to enable effective application of the active component to the skin. It can be removed with water and is safe to the skin and inner tissue of human and animal.

Description

Detailed Description of the Invention

[0001]

The present invention relates to cosmetics, external medicines,
The present invention relates to an external preparation composition used for external skin products, quasi-drugs, and the like, and more specifically, to form a film by applying it on the skin, mucous membranes, etc., and effectively apply the active ingredient to the skin. The present invention relates to a film-forming external preparation characterized by the following: It can be applied to antiperspirants, insect repellents, antibacterial agents, antiphlogistics and analgesics, etc. by changing the active ingredients. Further, the present invention relates to a film-forming external preparation having a water-soluble film formed, which is inexpensive such as water, can be easily removed with a readily available and safe solvent, and is safe on the skin and body of humans and animals.

[0002]

2. Description of the Related Art Conventionally, there have been liquid application agents, ointments, patches, etc. as external preparations for skin application, and since they are administration means more efficient than oral administration, various products have been developed so far. Has been done. However, as mentioned above,
Although external preparations have advantages, they have various problems due to their physical properties and the like. For example, in the case of a liquid application agent, the penetration of the medicinal component into the skin was not sufficient, and it was difficult to continuously release the medicinal component to the skin surface. In ointments, the release of the medicinal component from the base is low, and because the ointment adheres to clothes and the like due to contact with clothes during operation, the medicinal component often decreases, and the medicinal effect is often reduced. Wasn't enough either. In patches such as poultices and plasters, where the skin expands and contracts due to the movement of joints or where the shape is complicated, the skin does not adhere sufficiently to the skin surface and easily peels off. There is also a problem with skin problems such as skin irritation due to long-term use.

In recent years, in order to solve such drawbacks, a film-forming external preparation has been proposed which uses a resin which is liquid or gel at the time of application and forms a film by drying after application. For example, Japanese Patent Application Laid-Open No. 51-75745 discloses a composition for polymer bandage, which comprises an acrylic copolymer and a plasticizer. However, since this composition is based on an acrylic copolymer, it lacks water resistance, and when used in high temperature and high humidity such as in summer, the cohesive force due to a large amount of sweat (particularly salts in the skin) on the skin surface As a result, the adhesion of the coating to the skin is reduced. Although these polymers have low skin irritation, the problem of toxicity of residual monomers still remains, and when applied to the skin or the like, the skin irritation of residual monomers occurs even if the skin adhesion is good. Further, this film-forming external preparation uses a water-soluble resin as a film-forming resin, and since it is a solvent mainly composed of water, its drying property is poor and it takes time to form a film.

On the other hand, Japanese Unexamined Patent Publication Nos. 3-275619 and 2
No. 145512 discloses that a water-insoluble polymer is used as a film forming resin. Although these have excellent water resistance, they cannot be easily removed when removing the coating from the skin,
In particular, when repeatedly applied, the applied product remains and the drug absorbability is reduced. In addition, all of the above compounds had low affinity with the drug, and were poor in drug release from the coating and in skin absorbability.

[0005]

In view of the above circumstances, the present invention solves the above-mentioned problems of the prior art, is quick-drying and non-greasy, and maintains a good film even in the presence of water, sweat, etc. The purpose of the present invention is to provide a film-forming external preparation that can be easily removed with water, forms a water-soluble film with high safety and high drug migration.

[0006]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention have substantially made an N-vinylacetamide polymer or its copolymer a film-forming resin, and the film formed is water-soluble. It was found that the film-forming external preparation characterized by being excellent in film-forming ability solves the above problems.

That is, according to the present invention, a homopolymer of N-vinylacetamide or a copolymer of N-vinylacetamide and a copolymerizable monomer thereof is used as a film-forming resin, and the film formed is water-soluble. The present invention relates to a characteristic film-forming external preparation.

The present invention also provides a compound represented by the general formula (1)

[Chemical 2] (In the formula, R ₁ is hydrogen, a methyl group, X is COOM, and M is
Is an alkali metal, COOC _n H _{2n + 1} where n = 0 to 8 is an integer, COOC _n H _2n OH is n = 1 to 5 is an integer, C
OOC _n H _2n OC _m H _{2m + 1} where n = 1 to 3 is an integer, m
= Indicates an integer of 1 to 4, OC _n H _{2n + 1} where n = 1 to 8 integer, an integer of OCOC _n H _{2n + 1} where n = 1 to 3. ) A copolymer of one or more ethylenic monomers represented by) and N-vinylacetamide, wherein the ethylenic monomer and N-vinylacetamide are contained in an amount of 50% or more of all monomers. The film-forming external preparation is characterized in that the above-mentioned copolymer is used as a film-forming resin, and the film formed is water-soluble.

The film-forming external preparation of the present invention is generally said to have weak acidity because the N-vinylacetamide polymer or copolymer used is substantially nonionic. It is considered that when the polymer or copolymer is applied to the anionic surface of the skin to form a film, the skin adhesion is higher than that of an ionic film-forming resin, and the presence of water and salt. Even underneath, the cohesive force can be maintained without the polymer chain expanding and contracting due to the interaction of ions,
The shape retention of the coating is suppressed, and it is possible to prevent the coating from swelling, collapsing and falling off. This is particularly effective for athlete's foot medicines, tinea medicines and the like which are used in the areas where sweat is easily sweated. Further, since the polymer or copolymer has nitrogen and oxygen atoms, the polarity of the formed film is increased and the solubility of the drug is improved, so that the drug can be prevented from precipitating as crystals, Also, the skin adhesiveness can be improved. Therefore, the film-forming external preparation of the present invention has excellent drug release from the film and skin absorbability.
In addition, since the polymer or copolymer is water-soluble, the hydrophilicity of the film is improved and absorbs water secreted on the skin surface, so that the skin adhesion of the pharmaceutical preparation is maintained and a satisfactory pharmacological effect is sufficiently obtained. It is obtained and an equilibrium state is established between it and the water vapor in the external environment, which prevents the skin from becoming moist and rash. Further, N-vinylacetamide has low toxicity such as skin irritation.

The ethylenic monomer represented by the general formula (1) used in the present invention is a polymer having flexibility and / or
Alternatively, it is added for the purpose of improving the thickening property. Specific examples of the monomer represented by the general formula (1) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, Hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, vinyl acetate, vinyl propionate, vinyl methyl ether, vinyl ethyl ether, hydroxyethyl (meth) acrylate, 2
-Hydroxypropyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth)
Acrylate, propylethyl (meth) acrylate,
Examples thereof include butoxyethyl (meth) acrylate, (meth) acrylic acid, sodium (meth) acrylate, potassium (meth) acrylate, and the like, or one or two of them.
More than one species can be used.

The film-forming external preparation of the present invention contains N-vinylacetamide and the general formula (1) as long as the formed film is water-soluble and does not impair the performance as a film-forming resin.
A monomer other than the ethylenic monomer represented by can be used in an amount of 0 to 50% by weight based on the total amount of the monomer. Examples of the monomer that can be copolymerized include functional monomers such as itaconic acid, maleic acid, maleic anhydride, crotonic acid, and acrylonitrile, and vinyl monomers, but not limited thereto.

Similarly, other polymers may be added as the film-forming resin, and those which are sufficiently compatible with the copolymer, or are compatible with each other to the extent that they become cloudy are preferred. . For example, these polymers include silicone rubber, polyisobrengone, styrene-block copolymer rubber, acrylic rubber, guar gum, locust bean gum, rubber-based thickening substances such as natural rubber, polyvinyl alkyl ether, polyvinyl alcohol, poly Vinyl acetate, vinyl ether, polyvinylpyrrolidone, carboxyl vinyl polymer, vinylpyrrolidone, vinylpyrrolidone vinyl acetate alkylamino acrylic acid copolymer, metacarboxybetaine metacarboxyester copolymer, styrene maleic acid copolymer, ethylene-vinyl acetate copolymer Copolymers, vinyl thickening substances such as vinyl acetate-polyvinyl alcohol copolymer, starch, pullulan, ethyl cellulose, cellulose acetate, hydroxyethyl cellulose, hydroxymethyl cellulose. Loin, hydro waist methyl cellulose, hydroxypropyl cellulose, hydroxypropyl cellulose phthalate methyl cellulose, carboxymethyl such cellulosic adhesive material methylcellulose, (meth) thickening material mainly composed of acrylic acid alkyl ester (meth) acrylate,
Polyether-based thickening substances such as polyethylene oxide may be mentioned, but these are added to such an extent that they do not affect the hydrophilicity of the film-forming external preparation.

Among the film-forming resins used in the present invention, N-
Vinyl acetamide and the ethylenic monomer represented by the general formula (1) are copolymerized to such an extent that the water-solubility of the film-forming resin is not impaired, and the total amount thereof is 50 to 100 of the total amount of the monomers.
% By weight, preferably 80-100% by weight.
When it is less than 50% by weight, the film-forming ability and the alcohol-philicity are remarkably lowered, and stickiness, stringiness and the like occur. The weight ratio thereof is preferably in the range of 95: 5 to 10:90, and when it exceeds this range, the solubility with the plasticizer, the alcohol-philicity and the salt resistance are significantly lowered. Further, it is more preferably 90:10 to 30:70, and the effect becomes remarkable in this range.

The polymer or copolymer can be produced by polymerizing or copolymerizing a desired monomer by a known technique using an initiator. For example, it is produced by aqueous solution polymerization, precipitation precipitation polymerization, reverse phase suspension polymerization, or the like. When the polymerization is complete, a viscous liquid, agar-like or powdery product is obtained. It was found that the polymer or copolymer obtained here has extremely good solubility in water and alcohols, and an extremely excellent film-forming resin can be obtained. Especially, since it is alcohol-philic, it is possible to prepare a film-forming external preparation that can form a water-soluble film without using water as a solvent, so it is more dry than conventional film-forming external preparations using water-soluble polymers. Excellent in performance. Further, the film-forming external preparation obtained by the present invention has a simple composition of only a film-forming resin, a plasticizer and / or a low boiling point solvent, has a high film-forming ability, can be prepared at an extremely low cost, and is formed. Due to the water solubility of the coating, it can be removed quickly and completely with water.

Examples of the plasticizer used in the present invention include polyhydric alcohols, polyether polyols, isopropyl myristate, diethyl sebacate, diethyl phthalate, diisopropyl adipate, glycerin monooleate, polyethylene glycol and polypropylene glycol. However, among these, polyhydric alcohols are particularly desirable, and as polyhydric alcohols, propylene glycol,
Ethylene glycol, diethylene glycol, triethylene glycol, butylene glycol (dihydric alcohol), glycerin, trioxyisobutane (trihydric alcohol), erythritol, pentaerythritol (tetrahydric alcohol), xylit, adonite (penthydric alcohol), allozlucit, Sorbit (hexahydric alcohol)
Etc., but not limited to this. It is known that polyhydric alcohols enhance the transdermal absorbability of a medicinal component by increasing the solubility of the medicinal component in the skin and the moisturizing property of the skin. In addition, propylene glycol has an antiseptic action, and glycerin and 1,3-butanediol have an action to alleviate the skin irritation of ethanol. By this,
It can be said that the composition of the film-forming external preparation of the present invention can be simplified by using a polyhydric alcohol as the plasticizer.

Since the film-forming external preparation is also alcohol-philic, alcohols such as ethanol and isopropyl alcohol can be incorporated. Ethanol and isopropyl alcohol have a sterilizing and disinfecting action on the skin surface, and if these can be incorporated into a film-forming external preparation, they are expected to be effective in preventing skin irritation due to bacterial growth and sterilizing and disinfecting wounds. Further, since it is alcoholic and nonionic, it absorbs alcohol solutions such as antiseptic solutions, sweat containing salt, body fluids, etc., and the adhesiveness to the skin is maintained, and the adhesiveness is maintained.

To prepare the film-forming external preparation of the present invention, it is necessary to mix the film-forming resin or an aqueous solution or solvent solution thereof with a plasticizer, if desired, in the presence of water and / or a low boiling point solvent. If any, heat to dissolve.
The film-forming external preparation thus obtained is applied to the skin, nails and the like with a brush, fingertips, spray or the like, and a film is formed immediately as the low boiling point solvent is evaporated.

The low boiling point solvent used in the above is not particularly limited as long as it has a low boiling point and is volatile, but alcohols such as methanol, ethanol, butanol, isobutanol and propanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, etc. In addition to water-miscible organic solvents such as ketones, cellosolve, dioxane, dimethylformamide, and N-methylpyrrolidone, water-immiscible organic solvents such as ethyl acetate can be used. Of these, propanol and ethanol are particularly preferable from the viewpoint of odor after coating and drying. These can be used alone or in combination of two or more, and when a solvent miscible with water such as a lower alcohol is used, purified water can be added if necessary. The compounding ratio of the solvent is determined in terms of the viscosity of the composition, the solubility of the composition, the storage stability of the solution, the drying property, and the like.

The polymer or copolymer as the film-forming resin of the present invention is further used for percutaneous absorption or transmucosal treatment for the purpose of developing its properties more or improving the processability / moldability and quality. When used as a drug for absorption, for the purpose of improving the dispersibility and stability of the drug, it can be arbitrarily selected and selected from the substances acceptable as a drug according to the purpose. These include medicines, stabilizers, fillers, UV absorbers, fragrances, colorants, usability improvers, preservatives, preservatives, plasticizers, antiaging agents, softening agents, surfactants, deterioration inhibitors, etc. There is. These are arbitrarily added within a range that does not affect the properties of the obtained film-forming external preparation.

In order to use the formulation according to the invention as a vehicle for the administration of drugs, the drug can be included in the solution stage (or gel suspension stage). There are many drugs that can be administered in this way, for example glycol salicylate, methyl salicylate, piroxicam, triamcinolone, hydrocortisone acetate, indomethacin, ketoprofen, ibufenac, loxoprofen, thiaprofen, planoprofen, fenfen, diclofenac, felpinac, Ketronac,
Vermoprofen, napumetone, naproxen, flurbiprofen, fluocinonide, clobetasol propionate and other anti-inflammatory analgesics, clotrimazole, tolnaftate, econazole nitrate, omoconazole nitrate, thioconazole nitrate, ketoconazole nitrate, miconazole nitrate, isoconazole nitrate, virolnitrin Antifungal agents such as bimafucin, antibiotics such as tetracycline hydrochloride and chloramphenicol, antihistamines such as diphenhydramine and chlorpheniramine maleate, antiperspirants such as diethylamide and camphor, angina treatment such as nitroglycerin and isosorbide nitrate. Drugs, local anesthetics such as lidocaine and dibucaine, hormones, veterinary drugs, sleeping pills,
Antidepressants, sedatives, cardiovascular drugs, brain metabolism stimulants, fungicides, vitamins, enzyme preparations, keratoses therapeutics, anti-rheumatic drugs, anti-gout agents, antihypertensive agents, anticoagulants, etc. However, the drug is not limited thereto, and two or more kinds of these drugs can be used in combination as required.
Further, an auxiliary agent that promotes absorption of these drugs can be added, and examples of the absorption promoter include ethyl alcohol, isopropyl alcohol, butanol, 1,3-butanediol, propylene glycol, polyethylene glycol # 400, glycerin, Crotamiton, benzyl alcohol, phenylethyl alcohol, propylene carbonate, hexyldecanol, propanol, salicylic acid, urea, allantoin, dimethyl sulfoxide, dimethylacetamide, dimethylformamide, diisopropyl adipate, diethyl sebacate, ethyl laurate, lanolin, azone and nonionic There are substances such as a surface active agent, and one or more kinds thereof can be added if necessary. The amount to be added is determined in consideration of the balance between the film-forming property and the adhesive force to the skin.

The present invention is also used for a peelable eyeliner and a pack, and a cosmetic containing a perfume, an antiperspirant and the like can be prepared.

[0022]

EXAMPLES The usefulness of the present invention will be described below with reference to examples, but the present invention is not limited thereto.

Example 1 A 1-liter three-necked separable flask was equipped with a thermometer and a nitrogen introducing tube, and N-vinylacetamide 9 was attached thereto.
An aqueous solution prepared by dissolving 5 g and 5 g of sodium acrylate in 740 g of deionized water was charged. After introducing nitrogen gas to drive out dissolved oxygen, adjust the liquid temperature to 30 ° C., add 10 g of a 1% aqueous solution of 2,2′-azobis-2-amidinopropane dihydrochloride as a polymerization initiator, and insulate It was polymerized for 7 hours. The obtained polymer was chopped, poured into an acetone solution for dehydration, and then vacuum-dried to obtain a dried polymer. 50 g of the N-vinylacetamide copolymer obtained above was dissolved in 60 g of propylene glycol, 50 g of Eudragit E100 (EUDRAGID-E100 ROHM PHARMA CORPORATION), 3 g of indomethacin and 20 g of water with heating, and then ethanol was added thereto in an appropriate amount to homogenize. To obtain a film-forming external preparation.

Example 2 A thermometer and a nitrogen introducing tube were attached to a 1-liter three-necked separable flask, and N-vinylacetamide 1 was added thereto.
An aqueous solution prepared by dissolving 0 g and 90 g of acrylic acid in 740 g of deionized water was charged. After introducing nitrogen gas to drive out dissolved oxygen, adjust the liquid temperature to 30 ° C., add 10 g of a 1% aqueous solution of 2,2′-azobis-2-amidinopropane dihydrochloride as a polymerization initiator, and insulate It was polymerized for 7 hours. The obtained polymer was chopped, poured into an acetone solution for dehydration, and then vacuum-dried to obtain a dried polymer. 40 g of the N-vinylacetamide copolymer obtained above was dissolved in 50 g of 1,3-butanediol, 1 g of miconazole nitrate, 0.1 g of zinc oxide and 20 g of water under heating,
Then, an appropriate amount of isopropyl alcohol was added and uniformly mixed to obtain a film-forming external preparation.

Example 3 A 1-liter, 3-neck separable flask was equipped with a thermometer, a nitrogen introducing tube and a stirring rod, and 450 g of water was put therein, and the temperature was raised to 70 ° C. Then, stirring is started, and the polymerization initiator 2,
2'-azobis-2-aminodipropane dihydrochloride 80m
g in water at once and dissolved, 147 g of N-vinylacetamide, 63 g of methoxyethyl acrylate,
A mixed solution of 40 g of water was quantitatively added dropwise over 1 hour for reaction, and the mixture was aged for 3 hours. During this time, the reaction system is 7
I kept it at 0 ° C. 90 g of polyethylene oxide, 10 g of isosorbide dinitrate, 10 g of 1,3-butanediol and 210 g of water were added to this solution and uniformly dissolved to obtain a film-forming external preparation.

Example 4 A thermometer, a nitrogen introducing tube, and a stirring rod were attached to a 1-liter three-necked separable flask and 450 g of water was put therein, and the temperature was raised to 70 ° C. Then, stirring is started, and the polymerization initiator 2,
2'-azobis-2-aminodipropane dihydrochloride 80m
g in water at once and dissolved, 30 g of N-vinylacetamide and 70 g of hydroxyethylmethacrylate
g, and 40 g of water were added quantitatively dropwise over 1 hour to react, and aged for 3 hours. During this period, the reaction system was kept at 70 ° C. 70 g of polyethylene oxide, 5 g of fragrance and 210 g of water were added to this solution and uniformly dissolved to obtain a film-forming external preparation.

Example 5 A 1-liter, 3-neck separable flask was equipped with a thermometer, a nitrogen introducing tube and a stirring rod, and 450 g of water was put therein, and the temperature was raised to 70 ° C. Then, stirring is started, and the polymerization initiator 2,
2'-azobis-2-aminodipropane dihydrochloride 80m
g in water at once and dissolved, 20 g of N-vinylacetamide, 40 g of methyl acrylate, 40 g of hydroxyethyl methacrylate, and 40 g of water were added quantitatively dropwise over 1 hour to react, and further 3 Aged for hours. During this period, the reaction system was kept at 70 ° C. 90 g of polyethylene oxide, 50 g of N-methylpyrrolidone and 20 g of hydroxypropyl cellulose are added to this liquid.
And 210 g of water were added and uniformly dissolved to obtain a film-forming external preparation.

Example 6 A thermometer, a nitrogen introducing tube, and a stirring bar were attached to a 1-liter three-necked separable flask and 450 g of water was put therein, and the temperature was raised to 70 ° C. Then, stirring is started, and the polymerization initiator 2,
2'-azobis-2-aminodipropane dihydrochloride 80m
g in water at once and dissolved, 40 g of N-vinylacetamide, 30 g of methyl acrylate, 30 g of vinyl acetate, and 40 g of water were quantitatively added dropwise over 1 hour to react, and further 3 hours Aged During this period, the reaction system was kept at 70 ° C. 90 g of polyethylene oxide, 50 g of clotrimazole and 2 parts of water are added to this liquid.
10 g was added and uniformly dissolved to obtain a film-forming external preparation.

Comparative Example 1 30 g of Eudragit E100, 1 g of polyethylene glycol (# 1000) and 3 g of ketoprofen were dissolved in a mixed solution of 98 g of ethyl alcohol and 2 g of benzyl alcohol to obtain a film-forming external preparation.

Comparative Example 2 1 g of clotrimazole was added to 89 g of isopropyl alcohol.
Was added and dissolved, and 5 g of diethyl sebacate and 5 g of polyvinylpyrrolidone were added and heated to obtain a film-forming external preparation for external use.

Comparative Example 3 1.5 g of indomethacin was placed in a mixed solution of 4 g of crotamiton, 6 g of propylene glycol and 60 g of ethanol. It is heated to 60 ° C and dissolved to form an alcohol layer.
20 g of water is heated to 60 ° C., 6 g of hydroxypropyl cellulose is added, the resin is dispersed and kept at 60 ° C. to form an aqueous layer. The alcohol layer was poured into the aqueous layer all at once, dissolved with good stirring, and the total amount was adjusted to 100 g with water, followed by cooling to room temperature to obtain a film-forming external preparation.

Comparative Example 4 Pullulan 20 g was added to N-methylpyrrolidone 100 g 10 g.
After dissolving at 0 ° C., N. O. -Add 75 g of bistrimethylsilylacetamide and 100 g of toluene and heat,
Reaction was carried out by stirring at 140 ° C. for 5 hours. After cooling, the reaction solution was diluted with 800 g of toluene, stirred and poured into methanol,
The polymer was collected by filtration. The obtained polymer was further redissolved in toluene, precipitated with methanol, and collected by filtration twice, and dried in vacuum at 60 ° C. 5 g of the polymer obtained above was added with 45 g of octamethylcyclotetrasiloxane and 8 g of decamethylcyclopentasiloxane.
Heated and dissolved in. Indomethacin 0.5 in this solution
g, 30 g of isopropyl myristate and 15 g of dextrin fatty acid ester were added and mixed to obtain a film-forming external preparation.

Evaluation Test Example Each of the film-forming external preparations obtained in Examples and Comparative Examples was applied on a Bakelite plate with a thickness of 50 μm using an applicator, and then the state of film formation was observed. The results are shown in Table 1.

[0034]

[Table 1]

[0035]

From the above results, the present invention can exert the following effects. 1) It is excellent in water solubility, film-forming property and sticking property, and can be prepared at extremely low cost. 2) When it is applied to the skin, it forms a film with excellent uniformity and therefore does not impair the appearance, and is not irritating and highly safe. 3) Since it has an affinity for alcohol, it is possible to prepare a film-forming external preparation using a solvent mainly composed of alcohol, so that it has excellent dryness. 4) It can be easily removed with water without deterioration of sticking property due to sweat or body fluid. 5) Since it is a hydrophilic and alcohol-philic film-forming external preparation, it has a high affinity for both the drug and the absorption enhancer, especially when used for medical purposes, and it is highly safe without swelling, irritation or rash. A film is formed.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiko Oga 5-1, Ogimachi, Kawasaki-ku, Kawasaki-shi, Kanagawa Showa Denko K.K.

Claims (2)

[Claims] 1. A film characterized by using a homopolymer of N-vinylacetamide or a copolymer of a homopolymer of N-vinylacetamide and a monomer copolymerizable therewith as a film-forming resin, and the film formed is water-soluble. Molding type external preparation. 2. A compound represented by the general formula (1): (In the formula, R ₁ is hydrogen, a methyl group, X is COOM, and M is
Is an alkali metal, COOC _n H _{2n + 1} where n = 0 to 8 is an integer, COOC _n H _2n OH is n = 1 to 5 is an integer, C
OOC _n H _2n OC _m H _{2m + 1} where n = 1 to 3 is an integer, m
= Indicates an integer of 1 to 4, OC _n H _{2n + 1} where n = 1 to 8 integer, an integer of OCOC _n H _{2n + 1} where n = 1 to 3. ) A copolymer of one or more ethylenic monomers represented by) and N-vinylacetamide, wherein the ethylenic monomer and N-vinylacetamide are contained in an amount of 50% or more of all monomers. A film-forming external preparation characterized in that the above-mentioned copolymer is used as a film-forming resin, and the film formed is water-soluble.