High softness, high durability bath tissue incorporating high lignin eucalyptus fiber

Patent metadata

Field	Value
Publication number	US-9708774-B2
Application number	US-201615226939-A
Country	US
Kind code	B2
Filing date	Aug 3, 2016
Priority date	Jul 28, 2011
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A cellulosic tissue includes cellulosic fibers that include at least one of (a) chemically pulped fibers and (b) mechanically pulped fibers. The cellulosic fibers include (i) from about 10% to about 50% by weight eucalyptus fibers, and (ii) a percentage by weight of regenerated cellulosic microfibers. The cellulosic fibers further include virgin chemically pulped fibers, recycle fiber with a percentage by weight The eucalyptus fibers have been prepared from eucalyptus chips by alkaline peroxide mechanical pulping, exhibiting an ISO brightness of at least 0.82×(% VCP)+0.795×(% RF) 0.98 +0.84×(% APMP), in which % VCP is the percentage of virgin chemical pulp in the tissue, % RF, the percentage of recycle fiber, and % alkaline peroxide mechanical pulping (APMP), the percentage of APMP eucalyptus.

First claim

We claim:

1. A cellulosic tissue comprising:
(A) cellulosic fibers that include at least one of (a) chemically pulped fibers and (b) mechanically pulped fibers, wherein the cellulosic fibers include:
(i) from about 10% to about 50% by weight eucalyptus fibers; and
(ii) a percentage by weight of regenerated cellulosic microfibers; and

(B) virgin chemically pulped fibers, with a percentage by weight of recycle fiber,
wherein the eucalyptus fibers have been prepared from eucalyptus chips by alkaline peroxide mechanical pulping, exhibiting an ISO brightness of at least 0.82×(% VCP)+0.795×(% RF)0.98+0.84×(% APMP), and
wherein % VCP is the percentage of virgin chemical pulp in the tissue, % RF, the percentage of recycle fiber, and % alkaline peroxide mechanical pulping (APMP), the percentage of APMP eucalyptus.

2. The cellulosic tissue of claim 1 , wherein the eucalyptus fibers have a lignin content of at least about 23%, and exhibit an ISO brightness of at least about 82.

3. The cellulosic tissue of claim 2 , wherein the chemically pulped fibers are selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

4. The cellulosic tissue of claim 1 , wherein the weight percentage of the chemically pulped fibers in the tissue is at most 30%.

5. The cellulosic tissue of claim 4 , wherein the chemically pulped fibers include softwood fibers, and the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

6. The cellulosic tissue of claim 1 , wherein the tissue exhibits a machine direction (MD) stretch of between about 20% and about 30%.

7. The cellulosic tissue of claim 1 , wherein the chemically pulped fibers are selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

8. A method of manufacturing a tissue product, wherein a furnish comprising cellulosic fibers is deposited on a translating foraminous support and is thereafter dewatered and dried, the method comprising:
(A) a step of providing a cellulosic furnish comprising from 50% to 90% of cellulosic papermaking fibers that include (a) chemically pulped fibers and (b) mechanically pulped fibers, wherein the cellulosic papermaking fibers include (i) a percentage by weight of regenerated cellulosic microfibers, and (ii) from about 10% to about 50% eucalyptus fibers, an ISO brightness of at least about 84, a Canadian Standard Freeness (CSF) of at least about 400 ml, a bulk of between 2.2 and 4.2 cc/g, and a breaking length of between about 1.2 and 4.7 km;
(B) depositing the cellulosic furnish on a translating foraminous support to form an aqueous web of cellulosic fibers;
(C) removing the aqueous web of fibers from the support; and
(D) thereafter, dewatering and drying the removed web to form the tissue product.

9. The method of claim 8 , wherein the tissue exhibits a machine direction (MD) stretch of between about 20% and about 30%.

10. The method of claim 8 , wherein the chemically pulped fibers are selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

11. The method of claim 8 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by alkaline peroxide mechanical pulping.

12. The method of claim 8 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by pre-conditioning refiner chemical alkaline peroxide mechanical pulping.

13. A cellulosic tissue comprising:
a percentage by weight of cellulosic papermaking fibers that include chemically pulped fibers and mechanically pulped fibers,
wherein the cellulosic papermaking fibers have from about 5% to about 50% eucalyptus fibers, an ISO brightness of at least about 83, a Canadian Standard Freeness (CSF) of at least about 400 ml, a bulk of between 2.2 and 4.2 cc/g, and a breaking length of between about 1.2 and about 4.7 km.

14. The cellulosic tissue of claim 13 , wherein the tissue exhibits a machine direction (MD) stretch of between about 20% and about 30%.

15. The cellulosic tissue of claim 13 , wherein the chemically pulped fibers are selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

16. The cellulosic tissue of claim 13 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by alkaline peroxide mechanical pulping.

17. The cellulosic tissue of claim 13 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by pre-conditioning refiner chemical alkaline peroxide mechanical pulping.

18. A cellulosic tissue comprising:
from 50% to 90% cellulosic papermaking fibers that include chemically pulped fibers and mechanically pulped fibers,
wherein the cellulosic fibers have (i) from about 3% to about 30% by weight regenerated cellulosic microfibers, and (ii) from about 10% to about 50% eucalyptus fibers.

19. The cellulosic tissue of claim 18 , wherein the tissue exhibits a machine direction (MD) stretch of between about 20% and about 30%.

20. The cellulosic tissue of claim 18 , wherein the chemically pulped fibers are selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

21. A cellulosic tissue comprising:
(a) at least one of (i) about 40% to about 70% recycle fiber and (ii) a percentage of eucalyptus kraft fiber;
(b) a percentage by weight of regenerated cellulosic microfibers; and
(c) about 15% to about 30% eucalyptus fibers,
wherein the tissue has a basis weight of from about 10 to about 17 lbs per ply per 3000 sq ft ream, a specific geometric mean tensile of between about 35 and 45 g/3 in. per pound of basis weight, and a specific eight sheet caliper of between about 3 to about 3.5 mils per ply per eight sheets per pound of basis weight.

22. The cellulosic tissue of claim 21 , wherein the tissue exhibits a machine direction (MD) stretch of between about 20% and about 30%.

23. The cellulosic tissue of claim 21 , further comprising chemically pulped fibers selected from a group consisting of hardwood and softwood fibers, and wherein the weight percentage of chemically pulped softwood fibers in the tissue is at most 30%.

24. The cellulosic tissue of claim 21 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by alkaline peroxide mechanical pulping.

25. The cellulosic tissue of claim 21 , wherein the eucalyptus fibers have been prepared from eucalyptus chips by pre-conditioning refiner chemical alkaline peroxide mechanical pulping.

26. A cellulosic tissue comprising:
(a) at least one of (i) about 25% to about 40% softwood kraft fiber and (ii) from about 40 to about 60% hardwood kraft fiber;
(b) a percentage by weight of regenerated cellulosic microfiber; and
(c) about 15% to about 30% eucalyptus fibers,
wherein the tissue has a basis weight of from about 11 to about 17 per ply lbs per 3000 sq ft ream, a specific geometric mean tensile of between about 35 and 45 g/3 in. per pound of basis weight, and a specific eight sheet caliper of between about 3 to about 3.5 mils per eight sheets per pound of basis weight.

Assignees

• Georgia Pacific Consumer Products Lp

Inventors

• Lee Jeffrey A
• Sumnicht Daniel W

Classifications

• D21H11/08

  Mechanical or thermomechanical pulp · CPC title

• B32B29/005

  next to another layer of paper or cardboard layer · CPC title

• D21H11/02

  Chemical or chemomechanical {or chemothermomechanical} pulp · CPC title

• D21H27/40 Primary

  at least one of the sheets being non-planar, e.g. crêped (crêping or corrugating paper B31F) · CPC title

• D21H27/005

  relating to physical or mechanical properties, e.g. tensile strength, stretch, softness · CPC title