The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 2006
Filed:
May. 28, 2003
Dominic Pratt, Darmstadt, DE;
Toshio Kawagishi, Minamiashigara, JP;
Dominic Pratt, Darmstadt, DE;
Toshio Kawagishi, Minamiashigara, JP;
Kao Corporation, Tokyo, JP;
Fuji Photo Film Co., Ltd., Minamiashigara, JP;
Abstract
The present invention is directed to a hair dyeing composition comprising at least one azo dye of the following general formula (1):A—N=N—B  (1)where A=monovalent, optionally substituted heterocyclic group binding via the carbon atom to the azo group, that does not contain carboxy (—COH) or sulfo groups (SOH) or quaternary ammonium groups and B=heterocyclic, aromatic or alkyl group containing a dissociative proton and, which is free of carboxy (—COH) or sulfo groups (—SOH) or quaternary ammonium groups. Additionally, the present invention describes a method of dyeing human or animal hair by using such a dye and the use of this direct azo dye for dyeing human or animal hair. The use of this direct azo dye can impart the hair with an extremely vivid colour and has a less colour fade over the time.