JP4394494B2 - Aerosol composition and aerosol-type external preparation - Google Patents

Description

  The present invention relates to an aerosol composition, and more particularly, to an aerosol composition suitable for forming a protective film that is sprayed onto an affected area of the skin to cover the affected area, and an external preparation using the composition. .

  Conventionally, commonly used adhesive bandages are used by being affixed to the skin, so that the adhesive layer can cause irritation and irritation to the skin due to peeling damage as well as high adhesiveness that adheres securely to the skin. It is required to have no properties.

  There is a liquid bandage as one of this type of bandage. In general liquid bandages, the liquid bandage is applied directly to the affected area. After applying the liquid film component to the skin, it is stretched with fingers. Therefore, the formation of the film is complicated and it is difficult to make the film uniform even if it is extended.

  Recently, an aerosol-type external preparation has been proposed in which an aerosol composition is blended with various medicinal ingredients and sprayed onto the skin to form a thin film for treating diseases (see Patent Document 1).

  This aerosol-type external preparation uses an acrylic polymer that is hardly soluble in a solvent as a film-forming agent, so that the peelability from the coating is low, and if the amount of the solvent is increased, the drying property is poor and the skin is There was a drawback that it was sticky forever and the usability was bad.

  In order to avoid such drawbacks due to the blending of the acrylic polymer, an aerosol composition (see Patent Document 2) in which a cyclic silicone oil is blended with an aerosol composition containing an acrylic polymer film-forming agent or a polyhydric alcohol is used. A blended aerosol composition (see Patent Document 3) has been proposed.

  However, any aerosol composition still contains an acrylic polymer as a film-forming agent, and the poor solubility of the acrylic polymer is controlled by the addition of cyclic silicone oil or polyhydric alcohol. Accordingly, the blending amount of the cyclic silicone oil or the polyhydric alcohol has to be set, and there is still a drawback that the drying property is still low.

JP-A-1-230514 Japanese Patent Laid-Open No. 7-082142 JP-A-8-291050

  One problem to be solved by the present invention is to provide an aerosol composition that is excellent in dryness and peelability and that can alleviate skin irritation.

  Another problem to be solved by the present invention is to provide an aerosol-type external preparation that is excellent in dryness and releasability and can alleviate irritation to the skin.

  A first problem-solving means of the present invention is to provide an aerosol composition comprising a film-forming agent made of nitrified cotton, a plasticizer, an ester solvent, a lower alcohol, and a propellant.

  In the first problem-solving means of the present invention, the nitrified cotton preferably has a content of 0.5 to 30% by mass, and the plasticizer has a content of 0.2 to 15% by mass, The ester solvent preferably has a content of 10 to 50% by mass, and the lower alcohol preferably has a content of 1 to 20% by mass.

  Another problem-solving means of the present invention is to provide an aerosol-type external preparation characterized by being obtained by blending a medicinal component with the aerosol composition according to the first problem-solving means.

  The aerosol composition of the present invention uses nitrified cotton, which is more soluble in a solvent as compared to an acrylic polymer, as a film-forming agent, so there is no need to increase the amount of the solvent, and it has excellent drying and peeling properties. Alcohol promotes the dissolution of nitrified cotton as a co-solvent for ester solvents, and can alleviate the pain caused by penetration of the affected area of the skin by alleviating the ester solvent from irritating the skin.

  The embodiment of the present invention will be described in detail. As described above, the aerosol composition of the present invention includes a film forming agent composed of nitrified cotton, a plasticizer, an ester solvent, a lower alcohol, and a propellant. Yes.

  Nitrified cotton includes JISK6703 industrial nitrocellulose and the like, and those having a relatively low degree of polymerization are preferable in order to obtain appropriate viscosity, spray characteristics and high transparency of aerosol. Typically, those having the same components as paints such as commercially available nitrified cotton lacquer can be used. This nitrified cotton has a blending amount of 0.5 to 30% by mass, preferably 2 to 15% by mass. When the blending amount is less than 0.5% by mass, the viscosity of the aerosol is low and the adhesiveness is lowered, and when it exceeds 30% by mass, the viscosity of the aerosol becomes high and bubbles are generated, and a uniform film can be obtained. become unable.

  The plasticizer imparts flexibility to the coating, and as a preferred plasticizer, one or more of castor oil, isopropyl adipate, isopropyl myristate, isopropyl stearate, peppermint oil, 1-menthol is used. it can. The plasticizer has a blending amount of 0.2 to 15% by mass, preferably 2 to 5% by mass. If the blending amount is less than 0.2% by mass, the film is hard and brittle after drying, and if it exceeds 15% by mass, the film becomes too soft and causes stickiness.

  The ester solvent is a main solvent that dissolves nitrified cotton, and as this solvent, methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, amine acetate, ethyl lactate, cellosulbu acetate, or the like can be used. Considering odor and drying properties, methyl acetate or ethyl acetate is most suitable. The reason for limiting to the ester solvent is that the solvent having a low boiling point has a low drying property, such as ketones such as methyl ethyl ketone, methyl isobutyl ketone, diacetone alcohol, and cellosolves such as methyl cellosolve and ethyl cellosolve. This is because it cannot be used on the skin. The ester solvent has a content of 10 to 50% by mass. When the blending amount is less than 10% by mass, the nitrified cotton is not sufficiently dissolved, the viscosity of the aerosol stock solution is high and the container is not easily filled, and when it exceeds 50% by mass, it is formed when sprayed. The nitrified cotton concentration in the film is too low, resulting in film formation failure.

  Lower alcohol is blended for the purpose of accelerating dissolution of nitrified cotton as a co-solvent for ester solvents, lowering the viscosity of the liquid, improving mist properties as an aerosol, and obtaining a uniform film. Also, it has an action of alleviating the irritation to the skin by the ester solvent. As the lower alcohol, ethanol or isopropyl alcohol can be used. Alcohols having 4 or more carbon atoms such as butanol are not preferable for aerosol compositions used indoors because they are slow to dry and have odor. The lower alcohol is blended in consideration of the balance with the blending amount of the ester solvent, and the blending amount of the lower alcohol is 1 to 20% by mass, preferably 5 to 10% by mass. When the blending amount is less than 1% by mass, the nitrified cotton is not sufficiently dissolved, and when it exceeds 20% by mass, the concentration of the nitrified cotton is low and a uniform film cannot be formed.

  A propellant is a component that dissolves and sprays nitrified cotton, and a flammable gas such as dimethyl ether (DME) can be used alone, but when liquefied petroleum gas (LPG) is added to this, it dissolves DME. And the jetting properties of LPG are preferable because the jetting properties of nitrified cotton and the like can be improved. The blending amount of the propellant is appropriately set to such an extent that dripping does not occur when mist is formed and attached to the skin. When mixing DME and LPG, the mixing ratio is preferably 5: 5 to 9: 1. LPG alone cannot be used because its compatibility with nitrified cotton is low, and nitrified cotton gels and cannot be sprayed normally.

  The aerosol composition of the present invention uses nitrified cotton that is easily dissolved in a solvent as a film-forming agent. Therefore, when this aerosol composition is sprayed on the skin, a thin and uniform film can be formed and the drying property can be formed. In addition, the peelability is also improved. In addition, an ester solvent and a lower alcohol are used in combination to dissolve the nitrified cotton, so that the solubility of the nitrified cotton is improved and the irritation that the ester solvent gives to the skin is mitigated by the lower alcohol. Can be improved.

  The aerosol composition of this invention can mix | blend an appropriate medicinal component with it, and can utilize it for an aerosol type external preparation. The medicinal ingredients to be blended include skin protectants such as benzethonium chloride, zinc oxide and allantoin, bactericidal disinfectants and / or skin irritants such as menthol and α-camphor. These components are added to the aerosol composition in a blending amount of 0.0001% by mass to 5% by mass.

  The aerosol composition of the present invention can be produced by an ordinary aerosol production method. For example, it can be produced by dissolving nitrified cotton and a plasticizer in a mixture of an ester solvent and a lower alcohol, filling them in an aluminum can, and press-fitting a propellant through a valve.

  Describing two examples of the present invention together with one comparative example, in Examples 1, 2 and Comparative Example 1, the components of the aerosol composition and the blending amounts thereof were set as shown in Table 1.

  When the aerosol composition of Examples 1 and 2 was sprayed on the skin, it was possible to obtain a transparent and flexible coating film with good drying properties. However, the aerosol composition of Comparative Example 1 was applied to the skin. When sprayed on the film, it was confirmed that dripping occurred and a film having a thin film concentration and sufficient adhesion could not be obtained. This is because the aerosol compositions of Examples 1 and 2 use nitrified cotton that dissolves well in a solvent as a film-forming agent, whereas the aerosol composition of Comparative Example 1 has an acrylic resin with low solubility. Is used as a film-forming agent.

According to the present invention, the adhesiveness, drying property and peelability of a film formed by spraying on the skin are improved, and in particular, it is suitably used as an aerosol-type external preparation such as liquid bandages by adding medicinal ingredients. be able to.

Claims (4)

An aerosol composition comprising a film-forming agent made of nitrified cotton, a plasticizer, an ester solvent, a lower alcohol, and a propellant. It is an aerosol composition of Claim 1, Comprising: The said nitrified cotton has content of 0.5-30 mass%, The aerosol composition characterized by the above-mentioned. The aerosol composition according to claim 1 or 2, wherein the plasticizer has a content of 0.2 to 15% by mass, and the ester solvent has a content of 10 to 50% by mass. And the said lower alcohol has content of 1-20 mass%, The aerosol composition characterized by the above-mentioned. An aerosol-type external preparation characterized by being obtained by blending a medicinal component with the aerosol composition according to any one of claims 1 to 3.