Deinking agent and method of deinking through flotation using the deinking agent

摘要

A deinking agent comprising a compound represented by the following general formula I is herein provided:PPR.sup.1 O--(PO)m-- (EO)n--(XO)k--R.sup.2 (I)PP(wherein R.sup.1 represents an alkyl or alkenyl group having 12 to 22 carbon atoms; R.sup. 2 represents a hydrogen atom or an acyl group having 2 to 24 carbon atoms; PO, EO and XO represent a propylene oxide unit, an ethylene oxide unit and an alkylene oxide unit having not less than 3 cabon atoms, respectively; m=1. about.8; n=1040; and k is such a number that the number of total carbon atoms present in the polymerized XO unit ranges from 3 to 120; the PO and EO in Formula (I) being added through block-addition). The use of the deinking agent in the deinking methods, in particular, the flotation method permits the preparation of high quality reclaimed pulp having high brightness and a low content of residual ink and also ensures stable operations for the methods.