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:
Sep. 18, 2012
Filed:
May. 15, 2007
Iori Tomoda, Kanagawa, JP;
Yosuke Uchida, Chiba, JP;
Hiroyuki Nagatani, Tokyo, JP;
Ayano Kawae, Tokyo, JP;
Takahiro Cho, Saitama, JP;
Wakana Uesugi, Tokyo, JP;
Tetsuo Koshitsuka, Saitama, JP;
Iori Tomoda, Kanagawa, JP;
Yosuke Uchida, Chiba, JP;
Hiroyuki Nagatani, Tokyo, JP;
Ayano Kawae, Tokyo, JP;
Takahiro Cho, Saitama, JP;
Wakana Uesugi, Tokyo, JP;
Tetsuo Koshitsuka, Saitama, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
Provided are a method for producing bleached pulp, comprising processing unbleached pulp obtained by cooking a lignocellulose substance, for alkali-oxygen bleaching followed by treatment with peroxomonosulfuric acid and thereafter by multistage chlorine-free bleaching treatment starting from chlorine dioxide treatment; a method for producing bleached pulp, comprising processing the unbleached pulp for alkali-oxygen bleaching followed by chlorine-free bleaching treatment or totally chlorine-free bleaching treatment to bleach it to a degree of brightness of from 70 to 89%, and further followed by treatment with peroxomonosulfuric acid; and paper produced by the use of the bleached pulp produced according to these production methods, at a papermaking pH of at most 6. Provided are the efficient production methods for bleached pulp in which the color reversion resistance is enhanced in chlorine-free bleaching and the bleaching cost increase is prevented, and the paper produced by the use of the bleached pulp according to an acid papermaking process.