Patent · US Expired

Methods of deinking secondary fibers

US4518459A · kind A · utility

35Cited by
8References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 17, 1983
Grant dateMay 21, 1985
Priority date
Expiry dateJan 17, 2003

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S516/02
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

Washing methods of deinking secondary cellulose fiber (i.e., removing unwanted non-cellulose materials therefrom) are disclosed. These washing methods (as opposed to flotation methods) generally involve deinking the fiber with surface active agent (surfactant). The present invention utilizes a single foam-suppressing surface active agent consisting essentially of EQU R--(Ar)--(OC.sub.2 H.sub.4)m--(OC.sub.3 H.sub.6)n--Y; PA1 wherein R represents a monovalent higher aliphatic group containing from 6 to 24 carbon atoms, PA1 Ar represents an aromatic residue, PA1 --(OC.sub.2 H.sub.4)m--being a poly(ethylene oxide) chain, PA1 --(OC.sub.3 H.sub.6)n--being a poly(propylene oxide) chain; PA1 m is about 6 to about 15, PA1 n is about 12 to about 48, PA1 m:n is less than 1, and PA1 Y is selected from the group consisting of hydroxyl and benzyl ether. The present washing method of deinking reduces or eliminates objectionable foam, potentially provides energy savings yet maintains or improves the quality of the deinked fiber.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.