Astringent gel, its preparation and use

Claim 2

IN A PROCESS OF PREPARING AN ASTRINGENT GEL, THE STEPS WHICH CONSIST ESSENTIALLY OF A. PREPARING AN AQUEOUS SOLUTION OF A MIXTURE OF AN ASTRINGENT ALUMINUM SALT AND AT LEAST ONE OTHER ASTRINGENT METAL SALT-SELECTED FROM THE GROUP CONSISTING OF ZINC SALTS, ZIRCONIUM SALTS, AND MAGNESIUM SALTS, THE CONCENTRATION OF SAID MIXTURE OF ASTRINGENT SALTS IN SAID SOLUTION EXCEEDING 18%, B. DISSOLVING THEREIN A GELLING AGENT SELECTED FROM THE GROUP GROUP CONSISTING OF POLYVINYL ALCOHOL HAVING A MOLECULAR WEIGHT BETWEEN ABOUT 10,000 AND 96,000 AND UP TO 13% ACETYL GROUPS AND METHYL CELLULOSE HAVING A MOLECULAR WEIGHT BETWEEN ABOUT 13,000 AND 26,000 AND A DEGREE OF SUBSTITUTION BETWEEN ABOUT 1.3 AND 2.6 IN AN AMOUNT INSUFFICIENT TO FORM A GEL IN SAID CONCENTRATED SALT SOLUTION BUT SUFFICIENT TO YIELS A GEL WHEN THE RESULTING SOL OF THE MIXTURE OF ASTRINGENT METAL SALTS AND GELLING AGENT IS DILUTED WITH WATER TO A METAL SALT CONCENTRATION BELOW 18%, C. ADJUSTING THE PH OF THE SOLUTION OBTAINED IN STEP (A) OR STEP (B) TO A VALUE WHICH DOES NOT HAVE AN IRRITATING EFFECT ON HYMAN SKIN BYT WHICH IS BELOW THE LEVEL AT WHICH HYDROXIDES OF THE ASTRINGENT METALS PRECIPITATE, D. ADDING TO SAID SOL AN AMOUNT OF WATER SUFFICIENT TO REDUCE THE SSTRINGENT METAL SALT CONCENTRATION IN SAID SOL TO A CONCENTRATION LOWER THAN 18% BUT NOT SUBSTANTIALLY BELOW 13% AND E. ALLOWING THE DILUTED SOL TO STAND TO FORM THE ASTRINGENT GEL.

Claim 3

The process of claim 1, in which steps (a), (b), (c) and (d) are carried out at elevated temperature and the diluted sol is cooled in step (d) to room temperature.

Claim 4

The process of claim 1, in which the pH-value of the sol obtained in steps (a) and (b) is adjusted in step (c) to a pH between about 3.4 and about 4.0.

Claim 5

The process of claim 1, in which the gelling agent is added to the aqueous solution of astringent aluminum salts and the other astringent metal salts in an amount between about 1.0 and about 7.0%.

Claim 6

The process of claim 1, in which an emollient polyhydroxy alcohol is added to the sol before gelling in step (d).

Claim 7

The process of claim 5, in which the emollient polyhydroxy alcohol is an alcohol selected from the group consisting of glycerol and propylene glycol.

Claim 8

In a process of preparing an astringent gel, the steps which consist essentially of a. preparing an aqueous solution of a mixture of an astringent aluminum salt selected from the group consisting of ammonium aluminum sulfate, aluminum chloride, aluminum acetate, aluminum bromide and aluminum nitrate and at least one other astringent metal salt selected from the group consisting of zinc chloride, zinc sulfate, and zinc nitrate, zirconium chloride zirconium acetate, zirconium bromide, and zirconium nitrate, and magnesium chloride, magnesium bromide, magnesium acetate, and magnesium sulfate, the aluminum salt content of said mixture of astringent aluminum salt and the other astringent metal salts being between about 35 and about 80%, the concentration of said mixture of astringent salts in said solution exceeding 18%, b. dissolving in said solution a gelling agent selected from the group consisting of polyvinyl alcohol having a molecular weight between about 10,000 and 96,000 and up to 13% acetyl groups and methyl cellulose having a molecular weight between about 13,000 and 26,000 and a degree of substitution between about 1.3 and 2.6 in an amount between about 1% and about 7% said amount being insufficient to form a gel in said concentrated salt solution but sufficient to yield a gel when the resulting sol of the mixture of astringent metal salts and gelling agent is diluted with water to a metal salt concentration below 18%, c. adjusting the pH-value of the resulting solution of astringent metal salts and gelling agent to a pH between about 3.4 and about 4.0, d. adding to said sol an amount of water sufficient to reduce the astringent metal salt concentration in said sol to a concentration lower than 18% but not substantially below 13%, and e. allowing the diluted sol to stand to form the astringent gel.

Claim 9

In a process of preparing an astringent gel, the steps which consist essentially of a. preparing an aqueous solution of a mixture of an astringent aluminum salt selected from the group consisting of ammonium aluminum sulfate, aluminum chloride, aluminum acetate, aluminum bromide and aluminum nitrate and at least one other astringent metal salt selected from the group consisting of zinc chloride, zinc sulfate, and zinc nitrate, zirconium chloride zirconium acetate, zirconium bromide, and zirconium nitrate, and magnesium chloride, magnesium bromide, magnesium acetate, and magnesium sulfate, the aluminum salt content of said mixture of astringent aluminum salt and the other astringent metal salts being between about 35 and about 80%, the concentration of said mixture of astringent salts in said solution exceeding 18%, b. dissolving in said solution a gelling agent selected from the group consisting of polyvinyl alcohol having a molecular weight between about 10,000 and 96,000 and up to 13% acetyl groups and methyl cellulose having a molecular weight between about 13,000 and 26,000 and a degree of substitution between about 1.3 and 2.6 in an amount between about 1% and about 7% said amount being insufficient to form a gel in said concentrated salt solution but sufficient to yield a gel when the resulting sol of the mixture of astringent metal salts and gelling agent is diluted with water to a metal salt concentration below 18%, c. adjusting the pH-value of the resulting solution of astringent metal salts and gelling agent to a pH between about 3.4 and about 4.0, d. adding to said sol an amount of water sufficient to reduce the astringent metal salt concentration in said sol to a concentration lower than 18% but not substantially below 13%, and e. allowing the diluted sol to stand to form the astringent gel.

Claim 10

An astringent gel consisting essentially of water, an astringent aluminum salt selected from the group consisting of ammonium aluminum sulfate, aluminum chloride, aluminum acetate, aluminum bromide and aluminum nitrate and at least one other astringent metal salt selected from the group consisting of zinc chloride, zinc sulfate, and zinc nitrate, zirconium chloride, zirconium acetate, zirconium bromide, and zirconium nitrate, and magnesium chloride, magnesium bromide, magnesium acetate, and magnesium sulfate, the aluminum salt content of said mixture of astringent aluminum salt and the other astringent metal salt being between about 35% and about 80%, a gelling agent selected from the group consisting of polyvinyl alcohol having a molecular weight between about 10,000 and 96, 000 and up to 13% acetyl groups and methyl cellulose having a molecular weight between about 13,000 and 26,000 and a degree of substitution between about 1.3 and 2.6, the concentration of said gelling agent in said gel being between about 1% and about 7% and the concentration of said astringent metal salts in said gel being lower than 18%, but not substantially below 13%, and an agent adjusting the pH-value of said gel to a pH which does not have an irritating effect on human skin but which is below the level a which hydroxides of thE astringent metals precipitate, said gel being stable and non-deliquescent on prolonged storage.

Claim 11

An astringent gel consisting essentially of water, an astringent aluminum salt selected from the group consisting of ammonium aluminum sulfate, aluminum chloride, aluminum acetate, aluminum bromide and aluminum nitrate and at least one other astringent metal salt selected from the group consisting of zinc chloride, zinc sulfate, and zinc nitrate, zirconium chloride, zirconium acetate, zirconium bromide, and zirconium nitrate, and magnesium chloride, magnesium bromide, magnesium acetate, and magnesium sulfate, the aluminum salt content of said mixture of astringent aluminum salt and the other astringent metal salt being between about 35% and about 80%, a gelling agent selected from the group consisting of polyvinyl alcohol having a molecular weight between about 10,000 and 96, 000 and up to 13% acetyl groups and methyl cellulose having a molecular weight between about 13,000 and 26,000 and a degree of substitution between about 1.3 and 2.6, the concentration of said gelling agent in said gel being between about 1% and about 7% and the concentration of said astringent metal salts in said gel being lower than 18%, but not substantially below 13%, and an agent adjusting the pH-value of said gel to a pH which does not have an irritating effect on human skin but which is below the level a which hydroxides of thE astringent metals precipitate, said gel being stable and non-deliquescent on prolonged storage.

Claim 12

The astringent gel of claim 8, additionally containing an emollient polyhydroxy alcohol.

Claim 13

In a method of restoring the structure of sagging and loose skin areas, the step comprising applying by spreading the astringent gel of claim 8 to such skin.

Claim 14

In a method of restoring the structure of sagging and loose skin areas, the step comprising applying by spreading the astringent gel of claim 9 to the skin.

Claim 15

The method of claim 10, in which the astringent gel is spread on the skin and is covered by a covering textile layer.

Claim 16

The astringent gel as defined in claim 8, wherein said pH is between about 3.4 and 4.0.