Method for polymerization cast molding of lenses from hydrophilic gels
US4806287A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1987 |
| Grant date | Feb 21, 1989 |
| Priority date | — |
| Expiry date | Mar 5, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S425/808
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for the polymerization cast molding of lenses from hydrophilic gels. A hydrophobic liquid which is essentially immiscible with a hydrophilic polymerization mixture is introduced into a mold having a hydrophobic surface, followed by dosing of the hydrophilic monomer mixture which is allowed to polymerize to form a drop which is pressed, while polymerizing, into the mold with a punch having a hydrophobic molding surface. The polymerizing monomer mixture is maintained under the pressure of the punch until the end of the polymerization. Any overflow of the two liquids is allowed to escape between the mold and the punch. The apparatus comprises a concave mold with an inner hydrophobic, rotation-symmetrical surface, and a punch with a hydrophobic molding surface which when placed in relationship to the mold has an overflow space formed between the mold and the punch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.