| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing bleached kraft pulp having the combination of sufficiently low kappa number and high whiteness by bleaching unbleached kraft pulp with hydrogen peroxide. SOLUTION: The method for producing the bleached kraft pulp includes the following process: Unbleached kraft pulp is bleached with hydrogen peroxide within a pH range of 6-9 in the presence of 50-2,000 ppm of at least one kind of copper compound (A) among a cuprous or cupric salt or copper oxides based on bone-dry pulp weight and also three molar equivalents of at least one kind of nitrogen-containing coordinating compound (B) having at least two nitrogen-containing functional groups coordinated to copper ion in one molecule, based on the copper compound(s) A, in the unbleached kraft pulp. COPYRIGHT: (C)2008,JPO&INPIT
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