Patent · US Expired

Water-soluble copolymers containing vinylamine units as wet strength and dry strength agent for paper

US4978427A · kind A · utility

32Cited by

2References

11Claims

0Family size

Assignee

BASF SE

Inventors

Sigberg Pfohl · Speyer, DE
Michael Kroener · Mannheim, DE
Heinrich Hartmann · Schifferstadt, DE
Walter Denzinger · Speyer, DE

Key dates

Filing date	Sep 5, 1989
Grant date	Dec 18, 1990
Priority date	—
Expiry date	Sep 5, 2009

Classification

Technology area (CPC D)Textiles; Paper
CPC primaryD21H21/18
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

Water-soluble copolymers containing copolymerized vinylamine units are prepared by copolymerizing (a) from 95 to 10 mol % of N-vinylformamide and (b) from 5 to 90 mol % of an ethylenically unsaturated monomer from the group consisting of vinyl acetate, vinyl propionate, C.sub.1 -C.sub.4 -alkyl vinyl ethers, the esters, nitriles and amines of acrylic acid and methacrylic acid and N-vinylpyrrolidone, and then eliminating from 30 to 100 mol % of the formyl groups from the copolymer. Preferred copolymers are copolymers of N-vinyl-formamide and vinyl acetate, in which from 30 to 100 mol % of the monomer units are hydrolyzed. The copolymers are used in papermaking to increase the dry strength and wet strength of the paper.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.