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. 12, 1996
Filed:
Apr. 27, 1993
James G Carlson, Lake Elmo, MN (US);
Jack G Truong, Minneapolis, MN (US);
Jeffrey 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 polyurethanes which can be used in magnetic media binders applications. The polyurethanes comprise multidentate chelating functional groups pendant from the polymer backbone, which groups are produced by esterification of backbone hydroxyl moieties with cyclic dicarboxylic acid anhydrides which also bear an additional polar functional group such as those selected from the group consisting of --H, --OH, --COOM, --SO.sub.3 M, --SH, --CH.sub.2 COOM, --SCH.sub.2 COOM, --P(=O)(OM).sub.2, --OP(=O)(OM).sub.2, and the like. Examples of anhydrides useful in preparation of the polyurethanes include anhydrides of citric acid, mercaptosuccinic acid, dimercaptosuccinic acid and nitrilotriacetic acid. The polyurethanes, which are optionally radiation curable, show high affinity for magnetic pigments, and blends of the polyurethanes with vinyl resins afford excellent binders for magnetic recording media.