| 摘要 |
<p>PURPOSE:To effectively decolor unclassified waste information-recording paper, especially back-carbon paper, to a state reusable as a paper-making material without classification by using an oxidation bleaching agent in bleaching step. CONSTITUTION:In the treating process of unclassified waste information- recording paper comprising a maceration step, a kneading step, a flotation step, a washing step and a bleaching step, an oxidation bleaching agent is used in the bleaching step to effectively decolor a back carbon paper (blue ink). Preferably, the paper bleached with the oxidation bleaching agent is subsequently further bleached with a dithionite.</p> |
