IP Library Granted Patent US 12,077,912
Granted Patent B2
US 12,077,912 · App. 17/805,474 · Granted Sep 3, 2024

Crosslinked pulps, cellulose ether products made therefrom; and related methods of making pulps and cellulose ether products

Inventors: Mengkui Luo (Auburn, WA); Michael Rea (Vancouver, WA); Angela Dodd (Seattle, WA); Andrew Dodd (Seattle, WA); Amy Anderson-Gaber (Kent, WA); Kris Lindenauer (Auburn, WA); Hugh West (Seattle, WA); Charles Miller (Federal Way, WA)
Assignee: INTERNATIONAL PAPER COMPANY
D21C9/004C08B11/00D21H11/04D21H11/12D21H11/20D21H15/04D21H15/10
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Quick Facts
Patent No.
US 12,077,912
App. No.
17/805,474
Granted
Sep 3, 2024
Kind
B2
Abstract

Pulps, cellulose ether products, and methods of making pulps are described.

Claims (30)

1. A method of making a pulp, comprising:

digesting a cellulosic feedstock to form a pulp;

bleaching the pulp to form a bleached pulp;

crosslinking cellulose fibers within the bleached pulp with a crosslinker to form a crosslinked pulp, wherein during crosslinking the bleached pulp has a consistency greater than 30%, and wherein an R18 value of the crosslinked pulp is greater than 92%; and

drying the crosslinked pulp;

wherein the pulp has a water retention value (WRV) in a range of 0.8 g/g to less than 1.0 g/g.

2. The method of claim 1 , wherein crosslinking the bleached pulp comprises providing an alkaline hydroxide to the bleached pulp; the method further comprising extracting the alkaline hydroxide from the crosslinked pulp after crosslinking the cellulose fibers.

3. The method of claim 2 , wherein crosslinking the bleached pulp comprises providing the alkaline hydroxide and the crosslinker to the bleached pulp a plurality of times.

4. The method of claim 1 , wherein an alkaline ion concentration coefficient of variability is less than 10%.

5. The method of claim 1 , further comprising forming the crosslinked pulp into a form selected from the group consisting of a roll, a bale, and fluff.

6. A crosslinked pulp formed according the method of claim 1 .

7. A method of making a pulp, comprising:

contacting wood fibers with a crosslinker and an alkaline hydroxide, wherein the wood fibers have a water content in a range of about 0 wt. % to about 50 wt. %;

heating the wood fibers, the crosslinker, and the alkaline hydroxide to provide crosslinked wood fibers; and

washing the crosslinked wood fibers to remove unreacted crosslinker and alkaline hydroxide;

wherein an R18 value of the pulp after crosslinking is greater than or equal to 93%;

wherein the pulp has a water retention value (WRV) in a range of 0.8 g/g to less than 1.0 g/g.

8. The method of claim 7 , further comprising recovering the alkaline hydroxide.

9. The method of claim 7 , further comprising neutralizing the crosslinked pulp to provide a neutralized pulp; washing the neutralized pulp to provide a washed pulp; and drying the washed pulp.

10. A pulp formed according the method of claim 9 .

11. A method of making a crosslinked cellulose pulp, comprising:

activating a cellulosic pulp with an alkali hydroxide at a consistency of greater than 4% to provide an activated pulp;

removing the alkali hydroxide from the activated pulp; and

crosslinking the activated pulp with a crosslinker at a consistency of greater than 20% and at a temperature in a range of 30° ° C. to 95° ° C. to provide a crosslinked pulp;

wherein the crosslinked cellulose pulp has a water retention value (WRV) in a range of 0.8 g/g to less than 1.0 g/g.

12. The method of claim 11 further comprising washing and pressing the crosslinked pulp to provide a pressed pulp.

13. The method of claim 12 further comprising diluting and neutralizing the pressed pulp.

14. The method of claim 11 further comprising recovering the alkali hydroxide removed from the activated pulp.

15. The method of claim 11 further comprising drying the crosslinked pulp.

16. A pulp formed according to the method of claim 11 .

Assignments (2)
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 Jun 6, 2022
From: LUO, MENGKUI; REA, MICHAEL; DODD, ANGELA; DODD, ANDREW; ANDERSON-GABER, AMY; LINDENAUER, KRIS; WEST, HUGH; MILLER, CHARLES
To: INTERNATIONAL PAPER COMPANY
Reel/Frame 060105/0031 →