Patent · US Expired

Process for the preparation of a melanic pigment by an enzyme route and its use in cosmetics

US5244497A · kind A · utility

11Cited by
9References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 5, 1991
Grant dateSep 14, 1993
Priority date
Expiry dateFeb 5, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC12P17/00
  • WIPO fieldPharmaceuticals
  • WIPO sectorChemistry

Abstract

The invention relates to a process for the preparation of a melanic pigment, comprising the polymerisation of a compound corresponding to the formula: ##STR1## in which: R denotes a hydrogen atom, an alkyl, alkoxy, hydroxyalkyl, SiR.sub.4 R.sub.5 R.sub.6 or aminoalkyl radical, or an aryl radical which is unsubstituted or substituted by OH, NH.sub.2, alkyl, alkoxy or NO.sub.2 ; PA0 R.sub.1 and R.sub.2 denote alkyl groups or together form a methylene or ethylene group which is optionally substituted by one or more alkyl groups, and R.sub.2 denotes hydrogen or COOH, in the presence of an oxidizing medium and of an enzyme with (per)oxidizing activity or of a compound which has a similar activity, and to powders which make use of them and to their cosmetic use.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.