Process for preparing water-in-oil type emulsion cosmetic composition containing L-ascorbic acid with improved stability
US6346257B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 4, 1999 |
| Grant date | Feb 12, 2002 |
| Priority date | — |
| Expiry date | Nov 4, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K2800/782
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Disclosed is a process for preparing water-in-oil type emulsion cosmetic compositions containing L-ascorbic acid. The use of 2-hydroxypropyl cyclodextrin and a water-in-oil type emulsion allow L-ascorbic acid itself to be preserved for a lengthy period of time with high functional maintenance. Even after being stored for a significant period of time, the water-in-oil type emulsion cosmetic compositions do not exhibit discoloration nor give out offensive odor nor show the separation of cosmetic ingredients. In addition, the cosmetic compositions keep L-ascorbic acid high in the effective whitening activity, such as melanin reduction and inhibitory activity against tyrosinase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.