| 摘要 |
<p>PURPOSE:To obtain a deinking agent, excellent in ink removing ability and operability, having a high (b) value, capable of providing deinked pulp with hardly any unpeeled ink and useful for recycling waste paper such as newspaper by using a specific compound. CONSTITUTION:The objective deinking agent is obtained by using a compound expressed by the formula [A is phenylene, 1-32C alkylene, alkenylene, hydroxyalkylene or hydroxyalkenyl; R is 8-24C alkyl, alkenyl, cycloalkyl or alkylphenyl having 6-16C alkyl; M is H, alkali (earth) metal, ammonium or organic base; (a) is 0 or 1; (n) is a number equal to the valence of M]. Furthermore, the above-mentioned deinking agent can be added in respective steps of pulping, kneading, dispersing, chemical mixing and refining; however, the deinking agent is preferably divided into the pulping step and subsequent steps and added. Its dividing weight ratio is (40/60)-(60/40) of the pulping step/ subsequent steps. The amount added is preferably 0.03-1.0wt.% based on the raw material waste paper.</p> |
