Polycaprolactone lens blocking material
US5763075A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Sep 13, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2878
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The present invention provides thermoplastic ophthalmic lens blocking compositions that have many advantages over traditional metal alloy materials. Preferred compositions comprise a homopolymer or copolymer of epsilon-caprolactone, have a number average molecular weight between 3,000 and 100,000, and a polydispersity less than 10. The composition may also comprise one or more modifiers, fillers or heat absorbing materials. In one embodiment, the composition is used to fill the cavity between a preformed lens block and a lens. In another embodiment the composition is used to form a lens block. Methods of holding a lens blank are taught. Tapes that provide a receptive surface against which the composition may be adhered are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.