Porous contact lens and method for making it
US5061057A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1989 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | May 25, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2035/0872
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In order to make hard and soft contact lenses having a pore diameter and a pore density optimum for use as oxygen permeable contact lenses, the contact lens after molding is subjected to irradiation of a polyvalent heavy ion beam having a mass number of 2 to 100 (preferably 10 to 80) and an ion energy of 10M eV (preferably 50M eV) or higher, at an ion radiation density of 10 to 10.sup.9 ions/cm.sup.2 (preferably 10.sub.2 to 10.sub.5 ions/cm.sup.2) and thereafter ultrasonically etched (preferably at 10 to 50 MHz) at a temperature of 4 to 50.degree. C. (preferably 10.degree. to 30.degree. C.) in the presence of chloroacetic acid (preferably tricholoracetic acid).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.