Rigid contact lenses with improved oxygen permeability
US5194556A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1991 |
| Grant date | Mar 16, 1993 |
| Priority date | — |
| Expiry date | Jan 9, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/043
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Hard polymers with extremely high oxygen permeability are described, which consist of the copolymerization product of 1-15% by weight of a poly(dimethylsiloxane) bearing multiple polymerizable vinyl groups and having a number-average molecular weight M.sub.n of 1000-7000, 20-50% of an oligosiloxanylalkyl (meth)acrylate, 25-50% of an at least three fluorine atoms containing vinyl-monomer, 0-30% of copolymerizable monomers, which by themselves as homo- or copolymers have a Shore-D hardness of at least 85, 1-25% of polyvinyl-crosslinking monomer of 200-1000 molecular weight, and 0-15% of a watersoluble, copolymerizable monomer. The novel polymers combine a Shore-D hardness of 70-85 with an oxygen permeability of 40-90 barrers, making them outstanding materials for the manufacture and use as rigid, gas-permeable contact lenses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.