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:
Mar. 23, 1999
Filed:
Mar. 17, 1997
James A Weldon, Eagan, MN (US);
Michael Govek, Lakeville, MN (US);
Carole Sedlock, Minneapolis, MN (US);
John H Ko, Woodbury, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
The present invention provides thermoplastic ophthalmic lens blocking compositions that have many advantages over traditional metal alloy materials. Preferred compositions comprise a blend of (i) a hydrocarbon resin, preferably an aromatic hydrocarbon resin; (ii) a side chain crystallizable hydrocarbon polymer or copolymer; and (iii) optionally an modifier or mixture of modifiers, preferably straight chain alcohols. The composition may also comprise one or more modifiers, fillers or heat absorbing materials. In one embodiment, the composition is used to fill the cavity between a preformed lens block and a lens. In another embodiment the composition is used to form a lens block. Methods of holding a lens blank are taught. Tapes that provide a receptive surface against which the composition may be adhered are disclosed.