Composition for permanent waving of human hair
US6017519A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1994 |
| Grant date | Jan 25, 2000 |
| Priority date | — |
| Expiry date | Feb 14, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K2800/88
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
This invention refers to a composition for permanent waving of human hair, containing thioglycolic acid or the salts thereof, preferably the ammonium salt, and comprising two compositions which are kept separate until application, whereof a Composition (A) contains at least an amino acid hydrochloride and at least one polyol or the methyl and ethyl ethers thereof, preferably 1,2-propanediol in aqueous solution, having a pH-value of preferably between about 4.5 and 6.5, and a Composition (B) which is kept separate from said Composition (A) until use contains ammonium carbonate, ammonium hydrogen carbonate, and (or) ammonium carbamate as alkalizing agent(s), having a pH-value between about 8 and 9.5, and both compositions are mixed before application whereby a pH-value between about 7 and 8 is obtained. The compositions, which are kept separate, present outstanding stability; upon application after admixture optimal waving performance and, at the same time, gentle treatment of the hair is achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.