Abstract: A printing paper, especially a newsprint base paper, comprising: a base paper; and a coating layer for improving surface strength of the coated paper and releasing-property when two sheets of the coated paper are stacked, which coating layer is formed on the base paper by using a coating-transcription system such as a gate roll coating system, which coating layer comprises at least either a homopolymer polyacrylamide or a nonionic-copolymer polyacrylamide in a coating weight of from 0.01 g/m.sup.2 to 0.2 g/m.sup.2, wherein the homopolymer polytcrylamide and the nonionic-copolymer polyacrylamide have a weight average molecular weight ranging from 20,000 to 250,000, thereby improving not only surface strength but also releasing-property in a printing paper, especially in a newsprint paper having a basis weight less than 46 gm.sup.2.
Type:
Grant
Filed:
December 12, 1996
Date of Patent:
January 11, 2000
Assignees:
Nippon Paper Industries Co., Ltd., Seiko Chemical Industry Co., Ltd.
Abstract: A newsprint paper coated with a surface treating agent including a polyacrylamide-based compound and a vinyl acetate/maleic acid half ester copolymer in an coating amount of 0.01 to 0.2 g/m.sup.2. By coating the surface treating agent which is capable of obtaining well-balanced surface strength and peeling strength, lightweight newsprint paper or high recycled pulp content newsprint paper suitable for offset printing can be obtained.
Type:
Grant
Filed:
June 2, 1995
Date of Patent:
December 16, 1997
Assignees:
Nippon Paper Industries Co., Ltd., Seiko Chemical Industry Co., Ltd.
Abstract: An aqueous dispersion containing urethane vinyl composite resin which exhibits superior dispersability properties. The composite resin is obtained by graft polymerizing vinyl monomers with dispersable polyurethane. The polyurethane exhibits an acid value of at least 20. The dispersable polyurethane is obtained by reacting a urethane prepolymer having isocyanate groups at its end with a polyol compound obtained by the semi-esterification of polycarboxylic acid with benzene rings or its anhydride with trimethylol ethane or trimethylol propane. The urethane prepolymer is produced by reacting polyol compounds with poly-isocyanate compounds and ranges in molecular weight of from about 800 to 3000.