EP 0953679 A1 19991103 - Paper strengthening agent and paper strengthening method
Title (en)
Paper strengthening agent and paper strengthening method
Title (de)
Papierfestigungsmittel und Verfahren zur Festigung von Papier
Title (fr)
Agent de renforcement pour papier et procédé de renforcement de papier
Publication
Application
Priority
- JP 12664398 A 19980422
- JP 17532898 A 19980609
Abstract (en)
There is provided a paper strengthening agent comprising a polymer dispersion manufactured by polymerizing a monomer containing (meth)acrylic acid in an aqueous solution and precipitating the produced polymer as fine particles, and which is added to a paper layer after a paper layer is formed, wherein (1) the concentration of the (meth)acrylic acid (co)polymer in said polymer dispersion is at least 5 wt%, (2) the average particle diameter of the (meth)acrylic acid (co)polymer particles in said polymer dispersion is 1 to 100 mu m, (3) the viscosity of said polymer dispersion is 30 to 5000 mPa.s immediately after and one month after the production, (4) the polymer particles can be recognized when said polymer dispersion is diluted 10 times with distilled water and the diluted dispersion is magnified by a factor of 400 and observed with a microscope, and (5) when the pH of said diluted dispersion is adjusted to 7.0 by adding alkali, said polymer particles are dissolved to form an aqueous solution. The paper strengthening agent prepared in this manner allows to obtain paper having increased paper strength by diluting with water, coating or impregnating onto a dry paper surface or wet paper surface, and drying the treated paper.
IPC 1-7
IPC 8 full level
D21H 21/20 (2006.01); D21H 17/37 (2006.01); D21H 19/82 (2006.01); D21H 21/18 (2006.01); D21H 23/26 (2006.01); D21H 17/43 (2006.01); D21H 21/52 (2006.01)
CPC (source: EP)
D21H 21/18 (2013.01); D21H 17/43 (2013.01); D21H 21/52 (2013.01)
Citation (search report)
- [XY] EP 0717056 A2 19960619 - HYMO CORP [JP]
- [Y] US 5045587 A 19910903 - TANAKA KATSUTOSHI [JP]
- [Y] EP 0036993 A1 19811007 - WOLFF WALSRODE AG [DE]
- [A] US 2999038 A 19610905 - DRENNEN THOMAS J, et al
- [DA] DATABASE WPI Section Ch Week 8544, Derwent World Patents Index; Class A14, AN 85-273498, XP002109240
Designated contracting state (EPC)
DE ES FI FR GB IT NL SE
DOCDB simple family (publication)
EP 0953679 A1 19991103; EP 0953679 B1 20020911; DE 69807843 D1 20021017; DE 69807843 T2 20030528; ES 2185086 T3 20030416; NO 323070 B1 20061227; NO 983091 D0 19980703; NO 983091 L 19991025; RU 2146317 C1 20000310; TW I224641 B 20041201
DOCDB simple family (application)
EP 98111753 A 19980625; DE 69807843 T 19980625; ES 98111753 T 19980625; NO 983091 A 19980703; RU 98113153 A 19980701; TW 88118763 A 19991029