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:
May. 19, 1992
Filed:
Mar. 09, 1988
Masatomi Ogawa, Ichihara, JP;
Mitsuhiro Murata, Ichihara, JP;
DIC-Hercules Chemicals, Inc., Tokyo, JP;
Abstract
A papermaking additive useful for papermaking in a neutral to alkaline pH region, which comprises as an active component a water-soluble copolymer comprising as constituent monomers (a) 0.1 to 20 mole % of a specific bisquaternary ammonium (meth)acrylamide, (b) 0 to 20 mole % of a specific acrylamide or acrylic ester derivative such as an aminoalkyl (meth)acrylamide or an aminoalkyl (meth)acrylate, or a salt thereof, (c) 50 to 99.9 mole % of acrylamide and/or methacrylamide, and (d) 0 to 10 mole % of an alpha,beta-unsaturated carboxylic acid and/or a salt thereof. The additive increases paper strength and filler retention and size retention.