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:
Jul. 06, 1993
Filed:
May. 12, 1992
Yoshio Takahashi, Kanagawa, JP;
Shigeto Hatanaka, Kanagawa, JP;
Mitsubishi Oil Co., Ltd., Tokyo, JP;
Abstract
The present invention relates to a sizing agent which exerts excellent sizing efficiency even under severe conditions, namely, at an elevated temperature in the papermaking step, or at high conditions with a limited aluminum sulfate addition. The sizing agent for paper of the present invention is derived from i) dehydration condensation of an alkenylsuccinic anhydride and an organic carboxylic acid with a polyalkylene polyamine and ii) saponification of the remaining carboxyl groups with alkali following the dehydration condensation. More particularly, the present invention relates to a water-soluble sizing agent which is obtained by mixing an alkenylsuccinic anhydride with 1 to 20 times by molar equivalent, based on said alkenylsuccinic anhydride, as much as an organic carboxylic acid, adding 0.1 to 2.0 times by molar equivalent, based on said alkenylsuccinic anhydride, as much as a polyalkylene polyamine thereto so as to perform dehydration condensation. An then, to make the reacted material soluble to water, the remaining carboxyl groups are saponified with an alkali in an amount almost corresponding to the saponification equivalent.