JPH0133442B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improved water-in-oil type (W/O type) emulsion stick cosmetic, which aims to have emollient properties for the skin, be stable without sweating or breakage, and be microorganism-resistant. Contamination-free W/O
We aim to provide emulsified cosmetics. Traditionally, emulsified cosmetics have been produced by mixing water with a gel consisting of a surfactant and polyhydric alcohols such as glycerin, mannitrate, fructose, starch, or carbohydrates, in a base material mainly consisting of oily ingredients. (Japanese Patent Application Laid-Open No. 103742/1982); produced by adding an aqueous solution of maltitol to a mixture of sorbitan oleate or diglycerin oleate and an oily substance or a pigment (Japanese Patent Application Laid-open No. 127841/1984); 54-49337)
etc. are known. These cosmetics contain polyhydric alcohols such as those mentioned above in their formulations in order to improve product stability, water retention, bending strength, spreadability on the skin, and improve mold release properties during molding. Alternatively, carbohydrates are added, but these can cause microbial contamination and do not always give satisfactory results. Therefore, as a result of intensive research into the effects of W/O type emulsified cosmetics, particularly surfactants, polyhydric alcohols, and carbohydrates, the present inventor found that
If a gel is generated in advance from a surfactant with an HLB of 9 or less and water, and this gel is added to an oil-based ingredient and emulsified, an emulsified makeup with the above characteristics can be created without adding the polyhydric alcohol or carbohydrates, etc. I found that I could get a lot of money. Furthermore, the present inventor has found that when an organic acid or a salt thereof is added to the gel of the above-mentioned surfactant and water, the stability and strength of the gel are improved, and a buffering effect is exhibited in a W/O emulsion system. It has also been found that glycols can be easily added as preservatives. The present invention was completed based on this new knowledge, and it is a W/O obtained by adding and emulsifying a gel generated from a surfactant with an HLB of 9 or less, water, and an organic acid or its salts to an oily component. The present invention provides an emulsified stick cosmetic. In the present invention, various surfactants with HLB of 9 or less are used, such as sorbitan fatty acid ester, glycerin fatty acid ester,
Examples include polyoxyethylene hydrogenated castor oil fatty acid ester, diglycerin fatty acid ester, polyoxyethylene hydrogenated castor oil, and polyoxyethylene alkylphenols. These surfactants can be used alone or in combination of two or more, and are preferably blended in an amount of 0.5 to 10% of the total composition. Further, the water used for gel formation is suitably 0.5 to 10 times the surfactant. Note that when a surfactant with an HLB of greater than 9 is used, no gel is formed with water, so even if it is added to an oil component and emulsified, a W/O type emulsion will not be obtained, and an O/O type emulsion will not be formed. A W-type emulsion is only partially produced. Even if such an O/W type emulsion is used, it is not possible to properly incorporate water into the oily components (wax, liquid oil, etc.) that are the constituent base materials of static cosmetics. You can't get cosmetics. As the oily component, known ones used in the production of static cosmetics are used, such as fats and oils such as castor oil and olive oil; waxes such as wood wax, lanolin, beeswax, carnauba wax, and candelilla wax; liquid paraffin. , hydrocarbons such as solid paraffin; ester oils, higher fatty acids and the like. Furthermore, examples of organic acids or their salts include citric acid, lactic acid, pyrrolidone carboxylic acid, and their alkali metal salts such as sodium and potassium. It is preferable to mix these in an amount of 0.05 to 5% of the total composition. To produce the W/O type emulsion stake cosmetic of the present invention, a surfactant is first added to a predetermined amount of water and stirred to form a gel. A predetermined amount of organic acid or its salt is added to this gel. On the other hand, if the oily component is solid, it is heated to make it liquid, and the gel prepared above is gradually added thereto under stirring to emulsify it. The emulsion thus obtained is placed in a mold and cooled to obtain the emulsified stick cosmetic of the present invention. Pigments, dyes, fragrances, preservatives, and antioxidants that are usually added to stick cosmetics are added to either the gel or oily component. and,
Glycols such as propylene glycol and 1,3-butylene glycol, which have conventionally been difficult to incorporate because they destroy the gel, can be added, and as a result, contamination by microorganisms can be prevented. As mentioned above, the W/O type emulsion stick cosmetic of the present invention is extremely easy to manufacture, and
It has various advantages such as excellent stability, water retention, bending strength, and spread on the skin, and less contamination by microorganisms. Next, an example will be given and explained. Example 1 State eye cream composition: 1 Liquid paraffin 51.2 (parts by weight) 2 Squalane 10.0 3 Solid paraffin 10.0 4 Candelilla wax 10.0 5 Lanolin 5.0 6 Preservative 0.1 7 Fragrance 0.2 8 Glycerol monooleate 3.0 9 Pyrrolidone carboxylic acid Soda 0.5 10 Purified water 10.0 Manufacturing method: (A) Dissolve 1 to 7. (B) Add solutions 9 and 10 to 8 to form a gel. (C) Add B to A and emulsify. After degassing this, 70
Pour into a molding container at ℃, cool and form into sticks. Example 2 State foundation composition: 1 Liquid paraffin 47.2 (parts by weight) 2 Solid paraffin 10.0 3 Sucrose fatty acid ester 5.0 4 Mixed pigment 15.0 5 Lanolin 5.0 6 Preservative 0.1 7 Fragrance 0.5 8 Diglycerine diisostearate 4.0 9 Sodium citrate 1.0 10 Citric acid 0.2 11 Propylene glycol 2.0 12 Purified water 10.0 Production method: Proceed in the same manner as in Example 1 to obtain a state foundation. Comparative example 1 State eye cream composition: (% by weight) 1 Liquid paraffin 44.7 2 Squalane 10.0 3 Solid paraffin 10.0 4 Candelilla wax 10.0 5 Lanolin 5.0 6 Preservative 0.1 7 Fragrance 0.2 8 Glyceryl monooleate 3.0 9 Sorbitol liquid ( 70% aqueous solution) 10.0 10 Purified water 7.0 Manufacturing method: Follow the same procedure as in Example 1 to obtain a static eye cream. This product is the state eye cream of Example 1 in which sorbitol is added to the gel without adding sodium pyrrolidone carboxylate.
Compared to Example 3, the structure of the stake was weaker and the bending strength was lower. Furthermore, since the emulsifying ability was poor, water retention was poor, light elongation could not be obtained, and the whiteness of the appearance was also reduced. Comparative Example 2 A static eye cream (comparative product 1) was prepared in the same manner as in Example 1, except that sodium pyrrolidone carboxylate was removed from the composition of Example 1, and purified water was added to 10.5 parts by weight. Comparative Example 3 A static foundation (comparative product 2) was prepared in the same manner as in Example 2, except that sodium citrate and citric acid were removed from the composition of Example 2, and purified water was added to 11.2 parts by weight. Test Example 1 The following comparative test was conducted on the eye cream of Example 1 (Invention Product 1) and Comparative Product 1. (1) Stability test based on hardness change <Sample> Product 1 of the present invention and comparative product 1 are filled and molded into a cylindrical container of 14 mmφ x 37 mm. this
Place in a constant temperature bath at 40℃, store for 1 day or 2 weeks, then remove and leave in a constant temperature bath at 20℃ for 2 hours. The sample was taken out from the container and cut into a 14 mmφ x 35 mm cylinder. <Hardness measurement> Measurement was performed using a rheometer NRM-2002J (manufactured by Fudo Kogyo Co., Ltd.) [adapter: piano wire cutter, V-shaped holder] under the conditions of a microwave of 500 g and a table rising speed of 6 cm/min. <Results> Three samples were tested and the results are shown in Table 1.

[Table] As is clear from Table 1, Product 1 of the present invention shows less change in hardness than Comparative Product 1, and has excellent stability. (2) Change in Appearance Product 1 of the present invention and Comparative Product 1 were filled into containers in the same manner as in (1), and the appearance was observed after storing them in a constant temperature bath at 40° C. for one month. As a result, the product 1 of the present invention remained unchanged from immediately after preparation, but the appearance of comparative product 1 changed to a transparent appearance. As is clear from this, product 1 of the present invention has better storage stability than comparative product 1. (3) Sensory test For those stored at 40℃ for 1 month in the same manner as in (2) (after being left at 20℃ for 2 hours after removal),
Pairwise comparisons were conducted among 15 women. The results are shown in Table 2, and compared to Comparative Product 1, Product 1 of the present invention showed no deterioration in organoleptic properties over time.

[Table] Test Example 2 The static foundation of Example 2 (invention product 2) and comparative product 2 were poured into a container, filled and molded, stored in a constant temperature bath at 40°C for one month, and then taken out. A pairwise comparison was conducted by 15 women on the samples that had been left at 20℃ for 2 hours. The result is the third
As shown in the table, the product 2 of the present invention showed no deterioration in organoleptic properties over time compared to the comparative product 2.

【table】

Claims (1)

[Scope of Claims] 1. A water-in-oil emulsion stick cosmetic obtained by adding and emulsifying a gel produced by a surfactant with an HLB of 9 or less, water, and an organic acid or its salt to an oily component. 2 The surfactant is sorbitan fatty acid ester,
Glycerin fatty acid ester, polyoxyethylene hydrogenated castor oil fatty acid ester, diglycerin fatty acid ester, polyoxyethylene hydrogenated castor oil,
The emulsified stake cosmetic according to claim 1, which comprises one type or a combination of two or more types of polyoxyethylene alkylphenols. 3. The emulsified stake cosmetic according to claim 1, wherein the organic acid is citric acid, lactic acid, or pyrrolidone carboxylic acid. 4. The emulsified stake cosmetic according to claim 1, wherein the salts are alkali metal salts.