| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain waste paper pulp without reducing its yield and pulp strength, containing less mingling materials in an equivalent level with a virgin LBKP (broad-leafed tree kraft pulp) and having a sufficient degree of whiteness suitably being used as a printing paper. <P>SOLUTION: This method for producing the waste paper pulp comprises processes 10, 20 of disintegrating the waste paper in >20% pulp concentration for removing foreign materials from pulp fibers and processes of bleaching the pulp fibers, which comprise at least 2 stages of a pre-bleaching process 40 and post bleaching process 50, while performing mechanical agitation by each of disc type dispersing machines. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
