Delivery of hydroxy carboxylic acids
US6267977A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2000 |
| Grant date | Jul 31, 2001 |
| Priority date | — |
| Expiry date | Jul 12, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61Q19/08
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention provides greater than 99% pure bis(triorganosilyl)hydroxycarboxylates of the general formulae: EQU R.sub.3 SiO--CHR.sup.1 --COO--SiR.sub.3 EQU R.sub.3 SiO--CHR.sup.1 --R.sup.2 COO--SiR.sub.3 wherein each R is independently a monovalent straight or branched chain alkyl or alkenyl group having from 1 to about 6 carbon atoms, or an aryl group, R.sup.1 may be hydrogen, a monovalent straight or branched chain alkyl group having from 1 to about 18 carbon atoms, or an aryl group, and R.sup.2 is a divalent straight or branched chain alkyl group having from 1 to about 18 carbon atoms, an aryl group, or a straight or branched chain alkaryl group having from 7 to about 18 carbon atoms; a process for producing the bis(trimethylsilyl)hydroxycarboxylates comprising the trimethylsilylation with hexamethyldisilazane of the corresponding hydroxy carboxylic acids; cosmetic formulation comprising the greater than 99% pure bis(trimethylsilyl)hydroxycarboxylates dissolved in aprotic media; and a method of delivering hydroxycarboxylic acids to the epidermis without apparent irritation or inflammation of the epidermis or stratum corneum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.