NEW MATERIAL:The fat-soluble elastin peptide of formual (R is aliphatic carboxylic acid residue; R' is alkyl; n is 2W300).

USE: Cosmetic. It is soluble in an oil base and can be compounded to an oil-based cosmetic. It is a pale yellow to pale yellowish brown crystal hardly soluble or insoluble in water.

PROCESS: The ligament or vascular wall constituting the dermatic tissue of mammals is treated with an acid or an alkali, and then extracted e.g. by boiling (hot) oxalic acid treatment, hydrolysis with an alkali containing alcohol, digestion with elastic, etc. The obtained elastin peptide solution is mixed with a dilute alkali solution, added dropwise with a carboxylic acid halogenide, and stirred. The product is filtered, washed, and crystallized to obtain the compound of formula.