Hair-dyeing compositions based on para-phenylenediamine and ortho-aminophenol
US4370142A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1980 |
| Grant date | Jan 25, 1983 |
| Priority date | — |
| Expiry date | Jul 8, 2000 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K8/415
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The invention relates to compositions for hair dyeing which contain, as the oxidative dye-stuff, in a cosmetically acceptable medium, para-phenylenediamine and ortho-aminophenol, or their cosmetically acceptable salts, in a ratio para-phenylenediamine/ortho-aminophenol which is such that, after the addition of an equal volume of hydrogen peroxide of 20 volumes strength and application to the hair for 30 minutes, no Bandrowsky's base can be detected in the oxidizing dyeing composition. The compositions according to the invention make it possible to impart background colorations to the hair without the formation of Bandrowsky's base.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.