| 摘要 |
<p>Method of bleaching chemical paper pulp, in a manner which is preferably entirely chlorine-free, in a bleaching sequence which includes at least one acidic, sulphite-containing, reducing bleaching stage, which bleaching stage is carried out, under conditions which are in the main sulphonating, to a degree of sulphonation which exceeds 10 %. One or two oxidising bleaching stages follow(s) directly thereafter, without intervening washes. If single, this oxidizing bleaching stage can be acidic or alkaline; if there are two oxidizing bleaching stages, the first can be acidic and the second alkaline.</p> |
