Photochromic contact lenses and methods of manufacturing
US7368072B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2002 |
| Grant date | May 6, 2008 |
| Priority date | — |
| Expiry date | May 29, 2025 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29D11/00653
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Described are contact lenses having photochromic materials within the central or pupillary area of the lens and methods for manufacturing such lenses. In one method, a photochromic amount of at least one photochromic material is added to the pupillary region of a casting mold containing a polymerizable monomer that can be at least partially cured before and/or after the addition. Another method involves providing an amount of polymerizable photochromic monomer for the pupillary region and an amount of polymerizable non-photochromic monomer for the remainder of the contact lens in a casting mold. The photochromic and non-photochromic monomers can differ by their degree of polymerization, viscosity and/or density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.