| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for bleaching chemical pulp, by which at the previous stage of light bleaching, a bleaching stage used in an acid treatment and in an ordinary TCF (totally chlorine-free) bleaching is introduced or at the subsequent stage of light bleaching, an alkali hydrogen peroxide bleaching stage is introduced, the photoirradiation time of the light bleaching stage is significantly shortened, a TCF bleaching method having≥84% final ISO brightness is developed and chemical pulp having a high brightness is obtained. SOLUTION: In a pulp totally chlorine-free (TCF) bleaching, pulp delignified with oxygen is treated with an acid and bleached by a bleaching method used in an ordinary TCF bleaching is treated by light bleaching by an ultraviolet light at 100-400 nm wavelength or a visible light under an alkali condition or by both and bleached with an alkali and hydrogen peroxide. COPYRIGHT: (C)2007,JPO&INPIT
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