Alcogel sheet for cosmetic use, and method for producing same

Abstract

A cosmetic gel sheet suitable for a cosmetic field or a medical field is provided. The cosmetic alcogel sheet of the present invention comprises: a water-soluble nonwoven fabric or a water-soluble film; and an alcogel which is laminated on it and contains carboxy group-containing water-soluble polymer, polyalcohol and acid as essential components, and the sheet is characterized in that the water content of the gel is 30% by mass or less. It is more preferred that the carboxy group-containing water-soluble polymer is carboxy group-containing polysaccharides, and the polyalcohol is glycerin. The cosmetic alcogel sheet of the present invention can be manufactured by: drying an aqueous solution containing carboxy group-containing water-soluble polymer, polyalcohol and acid as essential components on a releasable sheet to manufacture gel, and then laminating the gel on a water-soluble nonwoven fabric or a water-soluble film.

Claims

1. A cosmetic alcogel sheet comprising: a water-soluble nonwoven fabric having a weight per unit area of 5 to 100 g/m.sup.2 or a water-soluble film having a thickness of 5 to 50 μm; and a gel sheet comprising an alcogel which is held on the water-soluble nonwoven fabric or the water-soluble film and contains carboxy group-containing water-soluble polymer, polyalcohol and acid as essential components, wherein the gel sheet alone has a thickness of 40 to 600 μm, and wherein a water content of the alcogel is 30% by mass or less.

2. The cosmetic alcogel sheet according to claim 1, wherein the water content of the alcogel is 20% by mass or less.

3. The cosmetic alcogel sheet according to claim 1 or 2, characterized in that that the carboxy group-containing water-soluble polymer is carboxy group-containing polysaccharides.

4. The cosmetic alcogel sheet according to claim 1 or 2, characterized in that that a content of the polyalcohol is 10 to 1000 parts by mass based on 1 part by mass of the carboxy group-containing water-soluble polymer.

5. The cosmetic alcogel sheet according to claim 1 or 2, characterized in that that the cosmetic alcogel sheet generates heat when attached on a skin.

6. The cosmetic alcogel sheet according to claim 3, characterized in that that the carboxy group-containing water-soluble polymer is one or more compounds selected from a group consisting of xanthan gum, gellan gum, alginic acid, hyaluronic acid and carboxymethyl cellulose.

7. The cosmetic alcogel sheet according to claim 1 or 2, characterized in that that the polyalcohol is glycerin.

8. The cosmetic alcogel sheet according to claim 1 or 2, characterized in that that the acid is one or more compounds selected from a group consisting of citric acid, tartaric acid, lactic acid and hydrochloric acid.

9. A method of manufacturing a cosmetic alcogel sheet, characterized in that: an aqueous solution comprising a carboxy group-containing water-soluble polymer, a polyalcohol and an acid as essential components is applied on a film or poured into a tray; the aqueous solution is dried to a water content of 30% by mass or less to form a gel sheet; and a water-soluble nonwoven fabric having a weight per unit area of 5 to 100 g/m.sup.2 or a water-soluble film having a thickness of 5 to 50 μm is laminated to manufacture the cosmetic alcogel sheet, wherein the gel sheet alone has a thickness of 40 to 600 μm.

10. The method of manufacturing a cosmetic alcogel sheet according to claim 9, characterized in that, when manufacturing the alcogel sheet, a content of the acid in the aqueous solution is an appropriate amount for allowing a pH of the aqueous solution to be 2.0 to 4.5.

11. The cosmetic alcogel sheet according to claim 1, wherein the gel sheet alone has a thickness of 80 to 250 μm.

12. The cosmetic alcogel sheet according to claim 1, wherein the gel sheet alone has a thickness of 80 to 250 μm, and the cosmetic alcogel sheet has a thickness of 100 to 350 μm.

13. The method of manufacturing a cosmetic alcogel sheet according to claim 9, wherein the gel sheet alone has a thickness of 80 to 250 μm.

14. The method of manufacturing a cosmetic alcogel sheet according to claim 9, wherein the gel sheet alone has a thickness of 80 to 250 μm, and the cosmetic alcogel sheet has a thickness of 100 to 350 μm.

15. The cosmetic alcogel sheet according to claim 1, further comprising paraffin oil.

16. The cosmetic alcogel sheet according to claim 1, further comprising a polyphenol.

Description

DESCRIPTION OF EMBODIMENTS

(1) Hereinafter, the present invention will be described with reference to Examples, but the present invention is not of course limited to the following Examples.

Manufacturing Method of Examples 1 to 6 as Well as Comparative Examples 1 and 2

(2) Aqueous solutions containing carboxy group-containing water-soluble polymer, polyalcohol and acid were stirred and mixed according to blending ratios (part by mass) described in Table 1 with a propeller type rotary stirrer to prepare raw material aqueous solutions. Tocopherol and Apprecier were dissolved into a small amount of ethanol and then added. The prepared raw material aqueous solutions were applied on polyethylene terephthalate films with a uniform thickness of 25 μm and then dried at 80° C. for 5 to 30 minutes with a gear type oven to obtain a cosmetic gel sheet with a thickness of approximately 200 μm. A water-soluble adhesive solution with a thickness after drying of about 10 μm was applied onto the water-soluble nonwoven fabric and dried at 80° C. for 20 minutes. Then the gel sheet was put onto the water-soluble nonwoven fabric and pressed by a roller to laminate the gel sheet and the nonwoven fabric.

(3) The water-soluble nonwoven fabric was used for Examples 1 to 5, and the water-soluble film was used for Example 6. The resulting sheets were cut to subject them to various evaluation.

(4) TABLE-US-00001 TABLE 1 Carboxy group-containing water-soluble polymer Xanthan Gellan Alginic Hyaluronic Polyacrylic Ethylene Components gum gum acid acid acid Glycerin Glycol Example 1 1 80 2 1 60 3 1 50 4 1 60 5 1 50 6 1 60 Comparative Example 1 1 80 2 1 60 pH of raw Acid material Citric Lactic Hydrochrolic Valuable component aqueous Components Acid Acid acid Tocopherol Apprecier Water solution Example 1 0.5 120 3.4 2 0.9 0.05 120 3.5 3 0.6 120 3.6 4 0.6 90 3.5 5 0.5 0.05 100 3.2 6 0.5 0.05 100 3.2 Comparative Example 1 0.5 120 3.4 2 0.9 0.05 120 3.5

(5) Standards and sources of each raw material are as follows. Hyaluronic acid with molecular weight of about 800,000 (FCH-80, Kikkoman Biochemifa Company) was used as hyaluronic acid. As the other raw materials, glycerin (concentrated glycerin, MIYOSHI OIL & FAT CO., LTD.), citric acid (NACALAI TESQUE, INC.), trisodium ascorbyl palmitate phosphate (Apprecier, SHOWA DENKO K.K.), tocopherol (NACALAI TESQUE, INC.), xanthan gum (SANSHO Co., Ltd.), gellan gum (Wako Pure Chemical Industries, Ltd.), CMC1260 as carboxymethyl cellulose (DAICEL FINECHEM LTD.), and alginic acid (Kikkoman Biochemifa Company) were used. Lactic acid, ethylene glycol, hydrochloric acid, and acetic acid of guaranteed reagent (NACALAI TESQUE, INC.) were used. G-Polymer, the water-soluble PVOH with the weight per unit area of 30 g/m.sup.2 (The Nippon Synthetic Chemical Industry Co., Ltd.) was used as the water-soluble nonwoven fabric. Solublon TS (thickness of 30 μm, AICELLO CORPORATION) was used as the water-soluble film. Liquidyn AR-2090 (VIGteQnos Corporation) was used as the water-soluble adhesive.

(6) The amounts of the hydrochloric acid and the acetic acid are shown in converted parts by mass from the aqueous solution reagent.

(7) (Comparison of Properties Among the Manufactured Polysaccharide Gel Sheets)

(8) Evaluation results of the polysaccharide gel sheets in Examples 1 to 6 and Comparative Examples 1 to 2 are summarized in Table 2. Note that, since the gels of Comparative Examples were not in a sheet form but in a liquid form containing a large amount of water, the various tests which postulate the object to be tested should be a gel sheet were meaningless, so that these gels were not evaluated.

(9) 1. Results of Properties Observation

(10) Observation results of flexibility and elasticity by naked eyes and touch are shown. “A” means that both flexibility and elasticity were sufficient. “B” means that flexibility was sufficient and elasticity was weak but not problematic in practical use. “C” means that the object to be tested was not a gel but in a liquid form.

(11) 2. Results of Water Content Measurement

(12) Measurement results of water content in the gel are shown. The water content measurements were determined from mass reduction values before and after heating samples at 90° C. for 1 hour.

(13) 3. Results of Test on Adhesiveness to Skin

(14) Test results on adherence to skin when the polysaccharide gel sheets (2 cm*2 cm) were applied inside a forearm of a human volunteer are shown. “A” means excellent adherence.

(15) 4. Results of Test on Warm Feeling

(16) Test results on a warm feeling to skin when the polysaccharide gel sheets (2 cm*2 cm) were applied inside a forearm of a human volunteer are shown. “A” means strong warm feeling to the skin, and “B” means some warm feeling.

(17) 5. Test on Solubility

(18) The polysaccharide gel sheets (2 cm*2 cm) were applied on a forearm of a human volunteer, on which 1 ml of water was dripped and then the skin was massaged over the sheets for 3 minutes to observe solubility of the gel. “A” means complete dissolution.

(19) 6. Test on Handling Property

(20) “A” means that the gel sheet has good mechanical strength and thus is not broken by careless handling to some degree, so that the gel sheet is extremely easy to handle.

(21) TABLE-US-00002 TABLE 2 Test Drying Water Test on on Test on time content, % adhesiveness warm Test on handling (min.) by mass Property to Skin feeling solubility property Example 1 30 9.4 A A A A A 2 30 9.2 A A A A A 3 25 18.5 A A A A A 4 25 17.8 A A A A A 5 20 25.6 B A B A A 6 25 18.5 A A A A A Comperative Example 1 10 55.6 C Impossible 2 5 77.4 C Impossible

(22) It can be found from Table 1 that the compositions of the aqueous solutions in both Examples and Comparative Examples are suitable for the raw material solution of the alcogel sheet.

(23) It can be found from Table 2 that, for stable generation of the alcogel, the raw material aqueous solution needs to be dried to the water content of 30% by mass or less, preferably 20% by mass or less.