Preparation of organic pieces of optical quality and especially organic lenses
US6248285A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1999 |
| Grant date | Jun 19, 2001 |
| Priority date | — |
| Expiry date | Sep 29, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/041
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The main aim of the present invention is a method of preparing photochromic or non-photochromic organic pieces of optical quality and especially organic lenses, by radical polymerisation of a mixture of radically polymerisable monomers, characterised in that it comprises: PA1 a) adjusting, by pre-polymerisation, the viscosity of said mixture, to a value between 0.4 and 2 Pa.s; PA1 b) pouring said pre-polymerised mixture into a mould; PA1 c) photogelifying, in said mould, said pre-polymerised mixture until its gel point; PA1 d) completing the polymerisation of said pre-polymerised and gelified mixture in said mould, by heat treatment; adding effective amounts of at least one thermal catalyst and of at least one photoinitiator intervening in said mixture of monomers for the implementation of said pre-polymerisation, photogelification and polymerisation; said photoinitiator(s) intervening in an amount less than or equal to 0.009 parts by weight per 100 parts by weight of said mixture of monomers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.