Method for cast molding contact lenses
US8845935B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 2009 |
| Grant date | Sep 30, 2014 |
| Priority date | — |
| Expiry date | May 15, 2031 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2011/0041
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention provide a method for cast-molding hydrogel contact lenses, especially silicone hydrogel contact lenses by using plastic molds of a poly(cycloalkylene-dialkylene terephthalate) copolymer. These plastic molds do not need to be degassed and stored in an oxygen-free atmosphere (e.g., N2 or Ar) before being used for cast-molding silicone hydrogel contact lenses in the absence of oxygen and resultant silicone hydrogel lenses can still have relatively high ion permeability and relatively low variation in targeted optical power, compared with silicone hydrogel lenses made from a conventional mold material, such as polypropylene. The invention also provides plastic molds for cast-molding silicone hydrogel contact lenses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.