Contact or intraocular lens from lightly crosslinked polymer or copolymer of 2-hydroxyethyl methacrylate and a method for producing thereof
US4997441A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1989 |
| Grant date | Mar 5, 1991 |
| Priority date | — |
| Expiry date | Jul 19, 2009 |
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 part of lower swellability than the surface layer, whereby the swellability of the surface layer decreases continuously from the surface towards the inner part to the swellability level of the inner part. The swellability of the surface layer is at the surface of up to 98% and the thickness of the surface layer is at utmost 100 .mu.m. The finally shaped lens 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.