Dissymmetric azomethine direct dyes and process for their preparation, cosmetic composition comprising at least one such dye and use thereof
US10927259B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2017 |
| Grant date | Feb 23, 2021 |
| Priority date | — |
| Expiry date | Dec 15, 2037 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K2800/884
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention relates to dissymmetric azomethine direct dyes of formula (I) and the leuco forms thereof of formula (II), and also to the use thereof for dyeing keratin fibres, in particular human keratin fibres such as the hair: in which formula (I) or (II) R1, R2, R3, R4, R5, R6, n and n′ are as defined in the description. The compounds of formula (I) or (II) according to the invention can give powerful, chromatic and sparingly selective colourings with good colour build-up, which are resistant to the various attacking factors to which keratin fibres may be subjected, such as inclement weather, light, washing and perspiration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.