Preparation of stable polyvinyl alcohol hydrogel contact lens
US5174929A · kind A · utility
2Cited by
6References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1990 |
| Grant date | Dec 29, 1992 |
| Priority date | — |
| Expiry date | Aug 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/043
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A dimensionally stable hydrogel contact lens of polyvinyl alcohol having an equilibrium water content of between about 70 to about 80 weight percent, based upon the total swollen lens weight, said lens having been annealed in a mold essentially conforming to the contact lens dimensions under substantially ambient non-drying setting conditions in the presence of an aqueous-organic annealing promoter solvent, for a period of time substantially sufficient to reach annealing equilibrium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.