IP Library Granted Patent US 8,475,631
Granted Patent B2
US 8,475,631 · App. 12/827,032 · Granted Jul 2, 2013

Reduction of fiber knots of cellulose crosslinked fibers by using plasma pre-treated pulpsheets

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Quick Facts
Patent No.
US 8,475,631
App. No.
12/827,032
Granted
Jul 2, 2013
Kind
B2
Abstract

The process of making crosslinked cellulose pulp fiber comprising plasma treating a sheet of cellulose pulp fiber before the sheet is impregnated with a crosslinking formulation which comprises a crosslinking agent and a catalyst, then defiberizing the treated cellulose pulp sheet to form treated defiberized cellulose pulp, then heating and curing the treated defiberized cellulose pulp to form intrafiber crosslinked cellulose pulp fibers.

Claims (15)

1. A process of making crosslinked cellulose pulp fiber, comprising

plasma treating at least one side of a sheet of cellulose pulp fiber, to provide a plasma treated sheet;

wherein the plasma treatment is corona discharge (CD) and wherein the corona discharge (CD) treatment is at least 54 Watts/m 2 /min;

treating the plasma treated sheet with a crosslinking agent, to provide a crosslinking agent treated sheet;

defiberizing the crosslinking agent treated sheet to form treated defiberized cellulose pulp; and

heating and curing the treated defiberized cellulose pulp to form individual intrafiber crosslinked cellulose pulp fibers, wherein the individual intrafiber crosslinked cellulose pulp fibers have a knot content that is less than individual intrafiber crosslinked cellulose pulp fibers formed with the crosslinking agent but without plasma treatment.

2. The process of claim 1 , wherein the corona treatment is in the range of 54 to 162 Watts/m 2 /min.

3. The process of claim 1 , wherein the defiberization is hammermilling the crosslinking agent treated sheet.

4. The process of claim 2 , wherein the defiberization is hammermilling the crosslinking agent treated sheet.

5. The process of claim 1 , where the plasma is generated using a gas selected from argon, helium, hydrogen, nitrogen, or oxygen.

6. The process of claim 1 , wherein the individual intrafiber crosslinked cellulose pulp fibers have a knot content of less than 20% based on the sonic fractionation test.

7. The process of claim 1 , wherein the individual intrafiber crosslinked cellulose pulp fibers have a knot content of less than 15% based on the sonic fractionation test.

8. The process of claim 1 , wherein the crosslinking agent comprises polyacrylic acid.

9. The process of claim 1 , wherein the sheet of cellulose pulp fiber is produced by a chemical process.

10. The process of claim 9 , wherein the chemical process is selected from the group consisting of a kraft process and a sulfite process.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 14, 2025
From: INTERNATIONAL PAPER COMPANY
To: GCF US HOLDINGS LLC
Reel/Frame 073563/0717 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 5, 2019
From: WEYERHAEUSER NR COMPANY
To: INTERNATIONAL PAPER COMPANY
Reel/Frame 049964/0838 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 3, 2010
From: STOYANOV, ANGEL; MILLER, CHARLES E.
To: WEYERHAEUSER NR COMPANY
Reel/Frame 024780/0286 →