JP2005053841A - Skin care preparation for external use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a skin care preparation for external use such as a skin lotion giving the skin humectancy and sustaining the humectant feeling. <P>SOLUTION: This skin care preparation for external use contains trehalose and starch compound(s) and also an electrolyte. The skin care preparation is in the form of an aqueous solution. In this skin care preparation for external use, the contents of the trehalose and the starch compound(s) are 0.1-10 wt.% and 0.01-10 wt.%, respectively, and the starch compound(s) are selected from red bean starch, corn starch, wheat starch, rice starch, potato starch, hydroxyethyl starch, hydroxypropyl starch, dextrin, α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention belongs to an external preparation for skin, and particularly relates to an external preparation for skin that prevents drying of the skin.

Since the skin is on the surface of the living body and is in direct contact with the outside world, it constantly receives various stimuli. When the moisture retention function of the stratum corneum and the moisture barrier function that prevents the loss of moisture inside the living body are reduced by such stimulation, the skin falls into dry skin. Conventionally, various skin external preparations containing a moisturizing component such as trehalose, sodium hyaluronate, butylene glycol have been studied in order to prevent skin dryness and protect cells.
JP 2000-34216 A

However, although the conventional skin external preparation has a moisturizing effect, the function of maintaining the moisturizing feeling has not been sufficient.
Therefore, an object of the present invention is to provide an external preparation for skin that can impart moisture retention to the skin and maintain the moisture retention.

In order to solve the above-mentioned problems, the external preparation for skin of the present invention is characterized by containing trehalose and starches.
According to the external preparation for skin of the present invention, trehalose imparts moisture retention to the skin, and starches have a barrier function that maintains the moisturizing feeling. As a result, when the external preparation for skin is composed of an aqueous solution containing an effective amount of trehalose and starch, it is not sticky during use, has excellent moisturizing properties, and can maintain its moisturizing feeling.

  By containing trehalose and starches, it is possible to obtain an external preparation for skin that exhibits moisturizing properties to the skin and maintains the moisturizing feeling.

As an embodiment of the skin external preparation of the present invention, various cosmetics such as lotion, lotion, essence, gel, milky lotion, cream, pack and mask can be considered. Furthermore, it can be enclosed in a nebulizer and used as a spray. The dosage form may be liquid, tablet, gel or powder.
Starch is a starch represented by the following chemical formula, which is a polymer of α-glucose, a starch derivative in which one or more hydrogen atoms in the starch molecule are each independently substituted with another group, In addition, it is a general term for partial hydrolysates of starch such as dextrin and cyclodextrin. The starches used in the present invention are compounds defined in this way, and exhibit the effect of solving the problems of the present invention when blended with other components in the skin external preparation and applied to the skin. As long as the chemical structure, properties, purity, and adjustment method are not limited to specific ones.

As the starch derivative, one or more of hydrogen atoms in the starch represented by the above chemical formula are each independently, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, vinyl group. And those substituted with an aliphatic hydrocarbon group such as an allyl group. Examples of the hydrolyzate of starch include dextrin, preferably α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin.
The external preparation for skin of the present invention is usually in the form of an aqueous solution, and the trehalose and starch content relative to the total amount is 0.1-10 wt% trehalose, 0.01-10 wt% starch, Trehalose is 0.5 to 4% and starches are 0.1 to 4%. This is because if trehalose exceeds 10% by weight, it tends to be sticky, and if the starch exceeds 10% by weight, it is difficult to form an aqueous solution.
The skin external preparation of this invention can also contain an electrolyte. Examples of the electrolyte include alkali metal or alkaline earth metal salts of inorganic acids such as hydrochloric acid, phosphoric acid, carbonic acid, and sulfuric acid, and alkali metals or alkalis of organic acids such as citric acid, malic acid, succinic acid, gluconic acid, and lactic acid. One type or two or more types selected from earth metal salts may be mentioned. For example, sodium chloride, potassium chloride, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, calcium phosphate, magnesium carbonate, calcium sulfate, sodium citrate, sodium malate, sodium gluconate, potassium gluconate, sodium lactate.
The external preparation for skin of the present invention can further contain components that are generally blended in cosmetics such as plant extract, water-soluble polymer, antioxidant, UV absorber, etc. An enhanced skin external preparation can be produced.

The plant extract referred to in the present invention includes raspberry extract, tomorrow leaf extract, rosemary extract, ukon extract, ginkgo biloba extract, jujube extract, perilla extract, aloe extract, green tea extract, mugwort extract, lavender extract, mulberry bark extract, Examples include barley extract, coconut extract, cypress extract, licorice (licorice) extract, algae extract, cuckoo extract, mint extract, safflower extract, loofah extract and the like.
Examples of the water-soluble polymer in the present invention include pectin, agarose, gellan gum, xanthan gum, chitosan, collagen, marine collagen, fibroin, sericin, gum arabic, carrageenan, alginic acid, hyaluronic acid, chondroitin sulfate, heparin, dermandan sulfate, heparan sulfate. , Keratan sulfate, carboxyvinyl polymer, carboxymethylcellulose, methylcellulose and the like.

Examples of the antioxidant referred to in the present invention include ascorbic acid, tocophenol, dibutylhydroxytoluene, and tocophenol acetate. Examples of the auxiliary agent include phosphoric acid, citric acid, ascorbic acid, maleic acid, malonic acid, succinic acid, fumaric acid, kephalin, hexametaphosphate, phytic acid, EDTA, and the like.
Examples of the ultraviolet absorber used in the present invention include benzophenone derivatives such as oxybenzone, methoxycinnamic acid derivatives such as 2-methoxyhexyl paramethoxycinnamate, and salicylic acid derivatives such as 2-ethylhexyl salicylate.
Hereinafter, the present invention will be specifically described based on examples.

Comparative Examples 1-2, Examples 1-3, and a control external preparation for skin containing the following components on a weight basis and the balance being purified water were prepared.
Comparative Example 1: Trehalose 2%, sodium gluconate 1%, dipotassium hydrogen phosphate 0.15%, potassium dihydrogen phosphate 0.05%
Comparative Example 2: Dextrin 1.5%, sodium gluconate 1%, dipotassium hydrogen phosphate 0.15%, potassium dihydrogen phosphate 0.05%
Example 1: Trehalose 2%, dextrin 1.5%, sodium gluconate 1%, dipotassium hydrogen phosphate 0.15%, potassium dihydrogen phosphate 0.05%
Example 2: Trehalose 10%, dextrin 3%, sodium gluconate 2%, dipotassium hydrogen phosphate 0.3%, potassium dihydrogen phosphate 0.09%
Example 3: Trehalose 2%, dextrin 1.5%, sodium gluconate 1%, dipotassium hydrogen phosphate 0.15%, potassium dihydrogen phosphate 0.05%, eggplant extract 2%, ethanol 4%, glycerin 2%
Controls: sodium gluconate 2%, dipotassium hydrogen phosphate 0.3%, potassium dihydrogen phosphate 0.09%

  Ten healthy women (22-58 years old) who have cosmetic use experience and have no skin diseases were subjects, and the use test was conducted on the skin preparations for control, Comparative Examples 1-2 and Examples 1-3. Without giving any information on the above-mentioned composition to the subject, randomly select and apply one of the skin external preparations of Comparative Examples 1-2 and Examples 1-3 to the left arm and the right arm. Three days later, the control was again applied to the left arm and the remaining one of the remaining comparative examples and examples was applied to the right arm, and the operation was repeated for 13 days. After application, the four items of feeling of use, moisturizing feeling, film feeling, and moisturizing feeling are compared with the control: “-2: considerably inferior to the control”, “-1: inferior to the control”, “0: control” Equivalent ”,“ +1: better than control ”, and“ +2: much better than control ”. The evaluation results are shown in Table 1. The numbers in the table represent the number of subjects who made each evaluation.

  Among the evaluation items, the moisturizing feeling is literally, the feeling of use is excellent (inferior) when there is no stickiness (existing), and the feeling of film is excellent when the presence of the film is felt (not felt) The moisturizing feeling is defined as the moisturizing feeling after 12 hours.

As can be seen from Table 1, in the moisturizing feeling, Comparative Example 2 containing no trehalose was almost equivalent to the control, but in other examples, the evaluation was superior to the control. This indicates that trehalose has a moisturizing action.
In the film feeling, Comparative Example 1 containing no dextrin was equivalent to the control, but the other examples were evaluated to be superior to the control. This indicates that dextrin has a film action.
In the moisturizing and maintaining feeling, compared to Comparative Example 1 containing trehalose but not containing dextrin, Examples 1 to 3 containing both trehalose and dextrin were all given excellent feeling of moisturizing and thus were given by trehalose. The moisturizing feeling is maintained by the film action of dextrin.
By the way, in the feeling of use, only Example 2 was inferior to the control. However, it was improved by lowering the concentration of trehalose and dextrin as in Examples 1 and 3. From this, it can be seen that blending both components at appropriate concentrations can provide a feeling of use suitable for an external preparation for skin.

Claims (6)

  An external preparation for skin comprising trehalose and starches.   The skin external preparation according to claim 1, comprising trehalose in an amount of 0.1 to 10% by weight, starches in an amount of 0.01 to 10% by weight, and comprising an aqueous solution.   One or two starches selected from azuki starch, corn starch, wheat starch, rice starch, potato starch, hydroxyethyl starch, hydroxypropyl starch, dextrin, α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin It is the above, The skin external preparation of Claim 1.   The external preparation for skin according to any one of claims 1 to 3, further comprising an electrolyte.   The electrolyte is an alkali metal or alkaline earth metal salt of an inorganic acid such as hydrochloric acid, phosphoric acid, carbonic acid or sulfuric acid, and an alkali metal or alkaline earth of an organic acid such as citric acid, malic acid, succinic acid, gluconic acid or lactic acid. The external preparation for skin according to claim 4, which is one or more selected from metal salts.   The skin external preparation in any one of Claims 1-4 which further contain a plant extract.