Polyurethane base lens resin, plastic lens comprising the resin and preparation method of the lens
US4929707A · kind A · utility
35Cited by
1References
27Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1989 |
| Grant date | May 29, 1990 |
| Priority date | — |
| Expiry date | Feb 3, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2011/0016
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Polyurethane base lens resins obtained by reacting one or more of sulfur-containing polyisocyanates compound with one or more of sulfur-containing polyols, and polyurethane base lenses comprising these resins are disclosed. A method for preparing polyurethane base lenses which comprises adding internal mold releasing agents to the mixture of the above polyisocyanates and polyols prior to casting polymerization is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.