US2658828A

Process of combining synthetic resins and other materials with cellulose

Abstract

This record has no abstract on file.

US2658828A, drawing sheet 1
Sheet 1 of 1

Term

Term ended

Expired 10 November 1970, 55.9 years ago.

  1. Priority and filed
  2. Granted
  3. Expired
  4. Today

3 claims: 3 independent, 0 dependent

  1. 1
    I claim:1. The stepwise process of incorporating substantial amounts of thermoplastic and thermosetting resins with Cellulosic pulp fibers to the formation of resin-containing paper webs, which consists in pretreating the cellulosic fibers in an aqueous suspension with a cationically active wetting agent which is normally active to coagulate subsequently added, resin dispersions, said cationically active wetting agent being an ionizable polar substance having a positively charged water-soluble portion and a larger water-insoluble surface active portion which includes a relatively long alkyl chain, the amount of such cationic active wetting agent, from about 5 to about 9.6% by weight based on the dry weight of the cellulosic fibers, being sufficient to render the fibers cationic active but not substantially in excess of such amount, treating the cationic active fibers in aqueous suspension with a watersoluble salt of a trivalent metal of the group consisting of the water-soluble chlorides, sulphates, acetates, formates, phosphates and nitrates of chromium, aluminum, nickel, ferric ion and gold, the amount of said salt, from about 5 to about 6% by weight based on the dry weight of the cellulosic fibers, being not greater thaii ah amount· which will be completely exhausted on the cationic active fibers, thereafter admixing an aqueous suspension Of the so-treated fibers, free from trivalent metal salt in the liquid phase, with a negatively charged aqueous dispersion of the resin, the amount of resin being from 5% to 300% by weight based on the dry weight of the fibers, and forming a paper web from the resulting paper stock. .
  2. 2
    The process defined in claim 1, in which the cationic active wetting agent and the salt are added, stepwise, during mechanical treatment of the cellulosic fibers in aqueous suspension.
  3. 3
    The process defined in claim 1, in which ’ the resin dispersion is added after mechanical treatment of the cellulosic fibers has been completed. DONALD Κ. PATTILLOCH. Number 2,315,675 2,325,302 2,330,524 2,330,525 2,338,602 2,345,543 2,350,719 2,356,718 2,369,992 2,394,009 2,407,376 2,456,567 2,484,315 2,492,702 2,563,897 References Cited in the file of this patent UNITED STATES PATENTS Name Date Trommsdorf--------Apr. 6, 1943 Britt______________July 27,1943 Shields____________Sept. 28, 1943 Shields____________Sept. 28,1943 Schur______________Jan. 4, 1944 Wohnsiedler et al. — Mar. 28, 1944 Bright et al. ________June 6, 1944 Wohnsiedler et al. — Aug. 22,1944 Treacy___________Feb. 20,1945 Pollard____________Feb. 5, 1946 Maxwell ------Sept. 10,1946 Scott ___ Dec. 14,1948 Scott ______________·- Oct· 11, 1949 Neubeft et al. ,___— Dec. 27, 1949 Wilsoii et al. ______ Aug. 14, 1951 OTHER REFERENCES Maxwell, Paper Trade J., May 13, 1943, pp. 39-41.