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. 21, 1995
Filed:
Apr. 30, 1993
Sadayuki Uchida, Kasai, JP;
Tomohiko Nakata, Kakogawa, JP;
Yoshihide Ishikawa, Himeji, JP;
Masao Hamada, Kakogawa, JP;
Shinichi Kimura, Kakogawa, JP;
Satoru Iwasa, Kakogawa, JP;
Harima Chemicals, Inc., Hyogo, JP;
Abstract
The invention provides a sizing agent with good stability, particularly which is rapid in getting started in the neutral zone and a method of producing the same. A sizing agent for papermaking in neutral zone is characterized by a main component of said sizing agent being selected from the group consisting of a diester of rosin-based substances having a dicarboxylic acid or acid anhydride group expressed by the following formula (I), ##STR1## (in which R.sub.1 represents a rosin acid residue or maleopimaric acid, R.sub.2 represents a dihydric alcohol residue and R.sub.3 represents a maleopimaric acid residue); and 2) a polyester reaction product expressed by the following formula (I'), ##STR2## (in which R'.sub.1 and R'.sub.5 represent a rosin acid residue or an .alpha.,.beta.-unsaturated polybasic carboxylic acid added rosin residue, at least one of them represents .alpha.,.beta.-unsaturated polybasic carboxylic acid added rosin residue, R'.sub.2 and R'.sub.4 represent polyhydric alcohol residues, R'.sub.3 represents a polybasic carboxylic acid residue being at least tribasic, x and z are integers of 1 to 3, y is 0, 1 or 2 and m and n are 1 or 2); and 3) a mixture comprising a rosin, a rosin modified by .alpha.,.beta.-unsaturated carboxylic acid and/or or an anhydride thereof and a polyhydric alcohol ester of rosin.