Contact or intraocular lens from lightly crosslinked polymer or copolymer of 2-hydroxyethyl methacrylate and a method for producing thereof
US4893918A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 1988 |
| Grant date | Jan 16, 1990 |
| Priority date | — |
| Expiry date | Jan 6, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/043
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Contact lens or intraocular lens from lightly crosslinked polymer of 2-hydroxyethyl methacrylate or from such its copolymer, where the 2-hydroxyethyl methacrylate component prevails over the second nonhydrophilic component, which contains a hydrophilic swellable transparent surface layer and an inner portion of lower swellability than the surface layer, whereby the swellability of the surface layer decreases continuously from the exterior of the surface layer towards the inner portion to the swellability level of the inner portion. The swellability of the exterior of the surface layer is at the surface layer of up to 98% and the thickness of the surface layer is at utmost 100 .mu.m. The finally shaped lense is treated with an alkaline reacting solution of a salt, in which the lens does not swell and the lens is then freed of all soluble substances by washing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.