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:
Jun. 17, 1980
Filed:
May. 02, 1978
Takashi Ishizuka, Ibaraki, JP;
Naoki Miwa, Ibaraki, JP;
Nitto Electric Industrial Co., Ltd., Ibaraki, JP;
Abstract
A coated article comprising a metal support and a baked layer of a water soluble heat-resistant insulating varnish containing a resin comprising ester groups and imide rings in the molecule dissolved in water using a volatilizable basic compound, the resin comprising the reaction product of (A) a carboxyl-containing polyesterimide resin having an acid value of about 30 to 150 obtained by reacting (a) a polyhydric alcohol component comprising at least one organic polyhydric alcohol and containing about 10 to 60 mol % of an imide ring-containing glycol of the general formula (I): ##STR1## wherein R.sub.1 is a trivalent aromatic group, R.sub.2 is a divalent organic group, and n is an integer of 1 to 3, with (b) a polycarboxylic acid component comprising at least one trivalent or divalent organic carboxylic acid or the anhydride thereof, where about 30 to 100 mol % of which comprises an aromatic tricarboxylic acid or the anhydride thereof so that the equivalent ratio (OH/COOH) between the polyhydric alcohol component and the polycarboxylic acid component is about 1.0 to 2.0; (B) 1,2,3,4-butanetetracarboxylic acid or an imide-forming derivative thereof; and (C) an organic diamine.