Producing soft contact lenses
US4347198A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 1980 |
| Grant date | Aug 31, 1982 |
| Priority date | — |
| Expiry date | Sep 25, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S425/808
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A soft contact lens is provided by: pouring an excess amount of an original solution for producing a soft contact lens into a concave mold; placing a convex mold on said concave mold and overflowing the excess of said original solution to thereby uniformly fill said original solution in a space between said concave mold and said convex mold; gelling said original solution between the two molds to form therebetween a lens having a tensile strength of at least about 0.1 kgf/cm.sup.2 ; immersing said lens and said two molds in a liquid to peel said lens from said molds; and extracting the thus-peeled lens via an extraction treatment with water. The "original solution" contains: PA0 a component A selected from the group consisting of monomers and hydrophillic polymers wherein the monomers yield hydrophillic component when polymerized; PA0 a compound B selected from the group consisting of monomers and hydrophobic polymers wherein the monomers yield hydrophobic component when polymerized; and PA0 a solvent C the weight ratio of A:B being from about 85:15 to about 55:45 and solvent C being about 5 to 95% by weight.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.