Method for lightening skin with ricinoleic acid

Abstract

Skin lightening additives and skin lightening compositions having at least one of a heterosubstituted, saturated or unsaturated aliphatic acid are described. The compositions are suitable for topical application and may comprise 12-hydroxystearic acid, ricinoleic acid or both.

What is claimed is: 
     
         1 . A skin lightening additive comprising a heterosubstituted, saturated or unsaturated aliphatic acid, or a mixture thereof. 
     
     
         2 . The skin lightening additive according to  claim 1  wherein aliphatic acid is 
       
         
           
           
               
               
           
         
         or a mixture thereof 
         wherein each R is independently hydrogen, hydroxyl, C 1-6  alkoxy, C 1-6  alkyl, arylalkyl or an amine, with the proviso that at least one R group comprises a heteroatom; each R 1  is independently hydrogen, C 1-5  alkoxy, C 1-6  alkyl, arylalkyl or an amine; n is an integer from about 7 to about 19; and s and e are each independently an integer from about 0 to about 8, where s+e≥6; q is an integer from about 6 to about 11; each r is independently an integer from 0 to 1, with the proviso that each r is not 1 when x is 1; x is an integer from 0 to 1 with the proviso that x is 0 when at least one r is 1; and each t is independently an integer from 1 to 7. 
       
     
     
         3 . The skin lightening additive according to  claim 1  wherein the heterosubstituted, saturated aliphatic acid is at least one of aleuritic acid; phloionolic acid, 9, 10, 13-trihydroxy-11-octadecenoic acid; 9, 13-dihydroxy-12-ethoxy-10-octadecenoic acid; 9-hydroxy-10, 12-octadecadienoic acid; 4, 14-dihydroxy-octadecanoic acid; 12-hydroxystearic acid or a mixture thereof and the heterosubstituted, unsaturated aliphatic acid is at least one of lesquerolic acid; ricinelaidic acid; ambrettolic acid; ricinoleic acid; beta-dimorphecolic acid; densipolic acid; 8-methoxy-13-hydroxy-9, 11-octadecadienoic acid; 7-oxo-octadecanoic acid; 9-oxo-octadecanoic acid; 12-oxo-octadecanoic acid; 10-oxo-14-methyl-pentadecanoic acid or a mixture thereof. 
     
     
         4 . The skin lightening additive according to  claim 1  wherein the skin lightening additive comprises the heterosubstituted, saturated aliphatic acid and heterosubstituted, unsaturated aliphatic acid at a weight ratio from about 10:90 to about 90:10. 
     
     
         5 . The skin lightening additive according to  claim 1  wherein the skin lightening additive consists essentially of heterosubstituted, saturated aliphatic acid, heterosubstituted, unsaturated aliphatic acid, or both. 
     
     
         6 . A cosmetic composition comprising
 a. a skin lightening additive comprising a heterosubstituted, saturated or unsaturated aliphatic acid, or a mixture thereof; and   b. a cosmetic carrier.   
     
     
         7 . The cosmetic composition according to  claim 6  wherein aliphatic acid is represented as formula I, formula II and/or formula III 
       
         
           
           
               
               
           
         
         or a mixture thereof 
         wherein each R is independently hydrogen, hydroxyl, C 1-6  alkoxy, C 1-6  alkyl, arylalkyl or an amine, with the proviso that at least one R group comprises a heteroatom; each R 1  is independently hydrogen, C 1-6  alkoxy, C 1-6  alkyl, arylalkyl or an amine; n is an integer from about 7 to about 19; and s and e are each independently an integer from about 0 to about 8, where s+e≥6; q is an integer from about 6 to about 11; each r is independently an integer from 0 to 1, with the proviso that each r is not 1 when x is 1; x is an integer from 0 to 1 with the proviso that x is 0 when at least one r is 1; and each t is independently an integer from 1 to 7. 
       
     
     
         8 . The cosmetic composition according to  claim 7  wherein the heterosubstituted, saturated aliphatic acid is at least one of aleuritic acid; phloionolic acid; 9, 10, 13-trihydroxy-11-octadecenoic acid; 9, 13-dihydroxy-12-ethoxy-10-octadecenoic acid; 9-hydroxy-10, 12-octadecadienoic acid; 4, 14-dihydroxy-octadecanoic acid; 12-hydroxystearic acid or a mixture thereof and the heterosubstituted, unsaturated aliphatic acid is at least one of lesquerolic acid; ricinelaidic acid, ambrettolic acid; ricinoleic acid; beta-dimorphecolic acid; densipolic acid; 8-methoxy-13-hydroxy-9, 11-octadecadienoic acid; 7-oxo-octadecanoic acid; 9-oxo-octadecanoic acid; 12-oxo-octadecanoic acid; 10-oxo-14-methyl-pentadecanoic acid or a mixture thereof. 
     
     
         9 . The cosmetic composition according to  claim 6  wherein the skin lightening additive comprises the heterosubstituted, saturated aliphatic acid and heterosubstituted, unsaturated aliphatic acid at a weight ratio from about 90:10 to about 10:90. 
     
     
         10 . The cosmetic composition according to  claim 6  wherein the skin lightening additive consists essentially of heterosubstituted, saturated aliphatic acid, heterosubstituted, unsaturated aliphatic acid, or a mixture thereof. 
     
     
         11 . The cosmetic composition according to  claim 6  wherein the cosmetic composition further comprises an alpha-hydroxy, beta-hydroxy acid, sunscreen or a mixture thereof. 
     
     
         12 . The cosmetic composition according to  claim 6  wherein the cosmetic composition further comprises a vitamin. 
     
     
         13 . The cosmetic composition according to  claim 12  wherein the vitamin is niacinamide. 
     
     
         14 . The cosmetic composition according to  claim 7  wherein the cosmetic composition further comprises niacinamide. 
     
     
         15 . The cosmetic composition according to  claim 6  wherein the composition further comprises conjugated linoleic acid, petroselinic acid or both. 
     
     
         16 . The cosmetic composition according to  claim 6  wherein the composition further comprises antioxidant. 
     
     
         17 . The cosmetic composition according to  claim 7  whereby a salt or derivative of the aliphatic acid represented by formula I, II and/or III is used. 
     
     
         18 . A method for lightening skin color comprising the steps of:
 a. contacting skin with the composition of  claim 6 ; and   b. suppressing melanin production.   
     
     
         19 . The method for lightening skin color according to  claim 17  wherein the skin composition further comprise niacinamide, conjugated linoleic acid, petroselinic acid, sunscreen, alpha-hydroxy acid, beta-hydroxy acid or a mixture thereof.