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:
Apr. 30, 1996
Filed:
Jul. 29, 1994
James G Carlson, Lake Elmo, MN (US);
Jeffery T Anderson, Lake Elmo, MN (US);
Nelson T Rotto, North St. Paul, MN (US);
Minnesota Mining and Manufacturing Company, Saint Paul, MN (US);
Abstract
The invention provides novel hydroxyl functional polyurethanes which can be used in magnetic media binders applications. The polyurethanes comprise strong carboxylic acid groups pendant from the polymer backbone, which groups can be produced by esterification of backbone hydroxyl moieties with cyclic dicarboxylic acid anhydrides. Examples of anhydrides useful in preparation of the polyurethanes include anhydrides of tetrachlorophthalic acid, tetrafluorophthalic acid, and dichloromaleic acid, etc. The polyurethanes, which are optionally radiation curable, show high affinity for magnetic pigments, and blends of the polyurethanes with vinyl and non-vinyl resins afford excellent binders for magnetic recording media.