The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 22, 1988
Filed:
Feb. 26, 1987
W James Hammar, St. Paul, MN (US);
Ronald F Ofstead, Maplewood, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
A process for preparing shaped articles and shaped hydrogel articles including ophthalmic devices comprises the steps of preparing a polymer or copolymer comprising units derived from an ethylenically-unsaturated monomer bearing at least one trihaloacetoxy-substituent group, thermoforming said polymer by heating in a mold or in sheet-form at a temperature in the range of 100.degree. to 400.degree. C. for about 5 seconds to 15 minutes, and then cooling said polymer, to provide a shaped article, solvolyzing the resulting shaped article to provide a hydroxy-substituted polymeric shaped article, and optionally hydrating said hydroxy-substituted polymeric shaped article to provide a shaped hydrogel article.