Brian K Devlin

US Patent:

20070037897, Feb 15, 2007

Filed:

Aug 8, 2006

Appl. No.:

11/500721

Inventors:

Guigui Wang - Cumming GA, US
Dawn Smith - Duluth GA, US
Juergen Vogt - Darmstadt, DE
John Lally - Lilburn GA, US
Brian Devlin - Suwanee GA, US

International Classification:

B29D 11/00
G02B 1/04

US Classification:

523106000, 264001320, 264001360

Abstract:

The instant invention pertains to a method and a fluid composition for producing contact lenses with improved lens quality and with increased product yield. The method of the invention involves adding a non-crosslinkable hydrophilic polymer into a fluid composition including a lens-forming material in an amount sufficient to reduce an averaged mold separation force by at least about 40% in comparison with that without the non-crosslinkable hydrophilic polymer and to provide a disparity of about 10 N or less in mold separation force. The non-crosslinkable hydrophilic polymer has a limited miscibility with the lens-forming material low enough to successfully and timely form an intact interfacial film with a sufficient thickness at an interface between the mold and the fluid composition therein, and has a structure that minimizes entanglement of the non-crosslinkable hydrophilic polymer in the interfacial film with the polymer matrix of the formed lens.