Kao Corporation

Nippon Paper Industries Co., Ltd.

Yasushi Ikeda

Hiromichi Takahashi

Takaaki Tadokoro

Yoichi Ishibashi

Toshiyuki Nishimori

Koji Hamaguchi

Yasuo Ishii

Takayuki Ikenaga

Atsuhito Mori

Zenbei Meiwa

Haruyuki Sato

Kenichiro Yabe

Toshiki Sowa

Mariko Ogawa

The present invention provides a method for producing a coated paper, including steps of coating a base paper coated with an aqueous solution of a water-soluble polymer with a coating liquid containing at least a pigment and an adhesive to produce a coated paper, and calendering the coated paper having a moisture content of not more than 5.5% by weight. The present invention also provides a method for producing a coated paper, including steps of coating a base paper having a moisture content of not more than 4% by weight with a coating liquid containing at least a pigment and an adhesive to produce a coated paper, and calendering the coated paper having a moisture content of not more than 5.5% by weight.

Method for producing coated paper

This invention is to provide a paper bulking promoter with which a highly bulky sheet can be obtained without impairing paper strength. Namely, this invention provides a process for producing a bulky paper, comprising the step of making paper from pulp in the presence of a bulking promoter comprising a cationic compound.

Paper bulking promoter

The present invention provides a paper quality improver for papermaking, for improving bulk value, brightness, and opacity of the pulp sheet. Further, the present invention provides a dry efficiency improver. A compound is used as the paper quality improver for papermaking, wherein the compound has less than 4% of lyotropic degree measured by a specific method and the compound satisfies at least two selected from (i) standard improved bulky value of not less than 0.02 g/cm, (ii) standard improved brightness of not less than 0.5 point and (iii) standard improved opacity of not less than 0.5 point. The compound is added internally into pulp slurry before or in papermaking step.

Paper quality improver for papermaking and method for producing pulp sheet

According to the present invention, a bulky sheet can be obtained without reducing the effect of a sizing agent. Thus, an ester compound having the melting point of not more than 100&deg; C. selected from (A) an ester compound of a polyhydric alcohol and a fatty acid and (B) an ester compound of a polyhydric alcohol and a fatty acid further including from more than 0 mole to less than 12 moles on the average of C oxyalkylene groups per 1 mole of the said ester compound is used as a paper bulking promoter.

This invention provides a paper bulking promoter with which a highly bulky sheet can be obtained without impairing paper strength. Namely, this invention provides a process for producing a bulky paper, having the step of making paper from pulp in the presence of a bulking promoter having at least one compound selected from the group consisting of a cationic compound, an amine compound, an acid salt of an amine compound, an amphoteric compound, an amide compound, a quaternary ammonium salt, and an imidazoline derivative.

The present invention provides a paper quality improver composition for papermaking, which is excellent in improved efficiencies of bulky value, brightness, opacity and the like of pulp sheet, demanded at lightening paper and increasing a blending amount of deinked pulp, even by adding a small amount thereof as well as which is further excellent in an improved efficiency of paper-strength. That is, the present invention provides a paper quality improver composition for papermaking; which comprises (A) a compound having lyotropic degree measured by a specific method of not less than 4% and satisfying at least two of (i) standard improved bulky value of not less than 0.02 g/cm , (ii) standard improved brightness of not less than 0.5 point, and (iii) standard improved opacity of not less than 0.5 point and (B) a water-soluble polymer satisfying an average molecular weight and/or a viscosity thereof of specific value.

Growing community of inventors

Wakayama, Japan

Yasushi Ikeda