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:
Sep. 01, 1981
Filed:
Sep. 25, 1979
Hisao Takagishi, Kyoto, JP;
Norio Kondo, Minoo, JP;
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
A durable aqueous solution of a thermosetting resin having a relatively high solid content which imparts a high degree of wet strength to paper, is produced by the reaction of an aliphatic dicarboxylic acid with a polyalkylenepolyamine to form a polyamidopolyamine, which is successively subjected to reaction with epichlorohydrin, the first reaction being carried out using a molar ratio of aliphatic dicarboxylic acid to polyalkylenepolyamine of 1:1.0 to 1.2 and continued until the viscosity at 25.degree. C. of 50% aqueous solution of resulting polyamidopolyamine reaches 400 to 1,000 cps, and the second reaction being carried out using epichlorohydrin in an amount of 1.6 to 1.7 moles per mole of the polyamide secondary amine and continued until the viscosity at 25.degree. C. of 15% aqueous solution of the resulting product reaches 30 to 150 cps.