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. 12, 2025
Filed:
Dec. 20, 2022
Kao Corporation, Tokyo, JP;
Bernd Nöcker, Darmstadt, DE;
Steven Breakspear, Darmstadt, DE;
Fariba Ghiasi, Darmstadt, DE;
Anna Neu, Darmstadt, DE;
KAO CORPORATION, Tokyo, JP;
Abstract
A method for dyeing keratin fibers, including mixing an aqueous dyeing composition containing a dye compound which is an anionic azo dye, a non-ionic azo dye, a salt thereof, or a mixture thereof, and an alkalizing agent having at least one basic functional group whose conjugated acid has a pKa value in a range of 6.0 to 8.0, with a second aqueous composition having a pH in a range of 1 to 6 to yield a ready-to-use composition having a pH in a range of 7 to 12. The method further includes applying the ready-to-use composition onto the keratin fibers and leaving it for a time period in a range of 1 min to 60 min, and rinsing-off the keratin fibers. The alkalizing agent is triethanolamine, 2-[4-(2-hydroxyethyl)-piperazin-1-yl]-ethane-1-sulfonic acid, a salt thereof, or a mixture thereof.