# US 5,702,693 A · Gypsum removal composition and method of removing gypsum from skin > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,702,693 A - Document ID: US5702693A - Status: Granted - Kind: A - Application number: 08/568,510 - Filed: 1995-12-07 - Granted: 1997-12-30 - Earliest claimed: 1995-12-07 - Assignees: DRAXIS Health Inc. - Inventors: Donald L. Simmons - Web page: https://patentgrep.com/patent/US5702693A ## CPC - C11D 7/265: {Carboxylic acids or salts thereof} - C11D 7/50: Solvents - A61F 13/04: Plaster of Paris bandages; Other stiffening bandages (A61F13/06 - A61F13/15 take precedence; orthopaedic casts made from stiffening bandages A61F5/01) - C11D 2111/40: Specific cleaning or washing processes - C11D: DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) ## Abstract The present invention provides a method for removal of gypsum from the skin of a patient. The method comprising the steps of: (i) applying to the skin of a patient an aqueous liquid composition comprising a water-miscible organic solvent, an acid and an emollient, the aqueous liquid composition having a pH in the range of from about 2 to about 5; (ii) dissolving the gypsum in the aqueous liquid composition; and (iii) removing the aqueous liquid composition containing dissolved gypsum from the skin of the patient. An aspect of the invention also relates to a liquid composition, particularly one for removal of gypsum from the skin of a patient, the composition comprising water, a water-miscible organic solvent, an acid and an emollient, the liquid composition having a pH in the range of from about 2 to about 5, with the proviso that the acid is not salicylic acid. The method and composition are particularly well suited for removal of gypsum deposits from the skin of a patient after removal of a Plaster of Paris-based cast from the patient. ## Claims ### Claim 1 A method for removal of gypsum from the gypsum skin of patient comprising the steps of: (i) applying to the skin of a patient an aqueous liquid composition consisting essentially of a water-miscible organic solvent, from about 1.7 to about 5.0 percent by weight of an organic acid having a pK.sub.a in the range of from about 1.0 to about 5.0 and from about 0.5 to about 5.0 percent by weight of an emollient, the liquid composition having a pH in the range of from about 2.0 to about 5.0, (ii) dissolving the gypsum in the aqueous liquid composition; and (iii) removing the aqueous liquid composition containing dissolved gypsum from the skin of the patient. ### Claim 2 (depends on 1) The method defined in claim 1, wherein the organic acid is present in an amount in the range of from about 2.0 to about 5.0 percent by weight of the aqueous liquid composition. ### Claim 3 (depends on 1) The method defined in claim 1, wherein the organic acid is present in an amount in the range of from about 2.0 to about 4.0 percent by weight of the aqueous liquid composition. ### Claim 4 (depends on 1) The method defined in claim 1, wherein the organic acid is present in an amount in the range of from about 2.0 to about 3.0 percent by weight of the aqueous liquid composition. ### Claim 5 (depends on 1) The method defined in claim 1, wherein the organic acid has a pK.sub.a value in the range of from about 2.5 to about 5.0. ### Claim 6 (depends on 1) The method defined in claim 1, wherein the organic acid has a pK.sub.a value in the range of from about 3.0 to about 4.0. ### Claim 7 (depends on 1) The method defined in claim 1, wherein the aqueous liquid composition has a pH in the range of from about 2.0 to about 4.0. ### Claim 8 (depends on 1) The method defined in claim 1, wherein the aqueous liquid composition has a pH in the range of from about 2.5 to about 3.5. ### Claim 9 (depends on 1) The method defined in claim 1, wherein the organic acid is selected from the group consisting of acetic acid, ascorbic acid, benzoic acid, citric acid, lactic acid, malic acid, malonic acid, oxalic acid, salicylic acid, glycolic acid, tartaric acid and mixtures thereof. ### Claim 10 (depends on 1) The method defined in claim 1, wherein the organic acid is selected from the group consisting of citric acid, lactic acid, malic acid and mixtures thereof. ### Claim 11 (depends on 1) The method defined in claim 1, wherein the acid is citric acid. ### Claim 12 (depends on 11) The method defined in claim 11, wherein the citric acid is present in an amount in the range of from about 2.0 to about 2.5 percent by weight of the aqueous liquid composition. ### Claim 13 (depends on 1) The method defined in claim 1, wherein the aqueous liquid composition comprises a water:water-miscible organic solvent weight ratio of from about 60:40 to about 40:60. ### Claim 14 (depends on 1) The method defined in claim 1, wherein the aqueous liquid composition comprises a water:water-miscible organic solvent weight ratio of from about 55:45 to about 45:55. ### Claim 15 (depends on 1) The method defined in claim 1, wherein the water-miscible organic solvent is selected from the group consisting of ethanol, isopropyl alcohol and mixtures thereof. ### Claim 16 (depends on 1) The method defined in claim 1, wherein the emollient is present in an amount of from about 0.5 to about 2 weight percent of the aqueous liquid composition. ### Claim 17 (depends on 1) The method defined in claim 1, wherein the emollient is selected from the group consisting of glycols, lipids, fatty acid esters, silicones, waxes, glycerides, vegetable oils, water soluble moisturizing agents, fatty alcohols, mineral oil, lanolin derivatives, animal extracts and mixtures thereof. ### Claim 18 (depends on 1) The method defined in claim 1, wherein the emollient is a fatty acid ester. ### Claim 19 A liquid composition for removal of gypsum from the gypsum skin of a patient, the composition consisting essentially of water, a water-miscible organic solvent, from about 1.7 to about 5.0 percent by weight of an organic acid having a pK.sub.a in the range of from about 1.0 to about 5.0 and from about 0.5 to about 5.0 percent by weight of an emollient, the liquid composition having a pH in the range of from about 2.0 to about 5.0, with the proviso that the acid is not salicylic acid. ### Claim 20 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid is present in an amount in the range of from about 2.0 to about 5.0 percent by weight of the aqueous liquid composition. ### Claim 21 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid is present in an amount in the range of from about 2.0 to about 4.0 percent by weight of the aqueous liquid composition. ### Claim 22 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid is present in an amount in the range of from about 2.0 to about 3.0 percent by weight of the aqueous liquid composition. ### Claim 23 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid has a pK.sub.a value in the range of from about 2.5 to about 5.0. ### Claim 24 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid has a pK.sub.a value in the range of from about 3.0 to about 4.0. ### Claim 25 (depends on 19) The liquid composition defined in claim 19, wherein the aqueous liquid composition has a pH in the range of from about 2.0 to about 4.0. ### Claim 26 (depends on 19) The liquid composition defined in claim 19, wherein the aqueous liquid composition has a pH in the range of from about 2.5 to about 3.5. ### Claim 27 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid is selected from the group consisting of acetic acid, ascorbic acid, benzoic acid, citric acid, lactic acid, malic acid, malonic acid, oxalic acid, glycolic acid, tartaric acid and mixtures thereof. ### Claim 28 (depends on 19) The liquid composition defined in claim 19, wherein the organic acid is selected from the group consisting of citric acid, lactic acid, malic acid and mixtures thereof. ### Claim 29 (depends on 19) The liquid composition defined in claim 19, wherein the acid is citric acid. ### Claim 30 (depends on 29) The liquid composition defined in claim 29, wherein the citric acid is present in an amount in the range of from about 2.0 to about 2.5 percent by weight of the aqueous liquid composition. ### Claim 31 (depends on 19) The liquid composition defined in claim 19, wherein the liquid composition comprises a water:water-miscible organic solvent weight ratio of from about 60:40 to about 40:60. ### Claim 32 (depends on 19) The liquid composition defined in claim 19, wherein the liquid composition comprises a water:water-miscible organic solvent weight ratio of from about 55:45 to about 45:55. ### Claim 33 (depends on 19) The liquid composition defined in claim 19, wherein the water-miscible organic solvent is selected from the group consisting of ethanol, isopropyl alcohol and mixtures thereof. ### Claim 34 (depends on 19) The liquid composition defined in claim 19, wherein the emollient is selected from the group consisting of glycols, lipids, fatty acid esters, silicones, waxes, glycerides, vegetable oils, water soluble moisturizing agents, fatty alcohols, mineral oil, lanolin derivatives, animal extracts and mixtures thereof. ### Claim 35 (depends on 19) The liquid composition defined in claim 19, wherein the emollient is a fatty acid ester. ### Claim 36 (depends on 19) The liquid composition defined in claim 19, wherein the emollient is present in an amount in the range of from about 0.5 to about 2 percent by weight of the liquid composition.