Soft durable tissue
View Patent ↗Single-ply throughdried tissue sheets, particularly suitable as bath tissue, are produced with at least three layers. One or both of the outer layers suitably contain predominantly softwood fibers and a chemical bonding agent. One or more of the inner layers suitably contains a chemical debonder. The resulting tissues have a high level of durability and softness.
1. A layered tissue sheet consisting of cellulose papermaking fibers, said sheet having two outer fibrous layers and one or more inner fibrous layers, wherein at least one of said outer layers contains a chemical bonding agent and wherein both outer layers are relatively stronger than at least one of the inner layer or layers, said tissue sheet having a geometric mean tensile energy from about 60 to about 200 grams (force)-centimeter and a geometric mean stiffness factor from about 2.0 to about 6.0 and having a cross-machine direction wet tensile strength of from about 75 to about 200 grams (force) per 3 inches.
2. A layered tissue sheet consisting of cellulose papermaking fibers, said sheet having two outer layers consisting primarily of softwood cellulosic fibers and one or more inner layers of papermaking fibers, wherein at least one of said outer layers contains a chemical bonding agent and one or more inner layers contains a chemical debonding agent and wherein both outer layers are relatively stronger than at least one of the inner layer or layers, said tissue sheet having a geometric mean tensile energy from about 60 to about 200 grams (force)-centimeter and a geometric mean stiffness factor from about 2.0 to about 6.0 and having a cross-machine direction wet tensile strength of from about 75 to about 200 grams (force) per 3 inches.
3. A layered, single-ply, throughdried bath tissue sheet consisting of cellulose papermaking fibers, said sheet having two outer layers consisting primarily of softwood fibers and one or more inner layers of papermaking fibers, wherein both of said outer layers contain a chemical bonding agent and one or more inner layers contains a chemical debonding agent and wherein both outer layers are relatively stronger than at least one of the inner layer or layers, said tissue sheet having a geometric mean tensile energy from about 60 to about 200 grams (force)-centimeter and a geometric mean stiffness factor from about 2.0 to about 6.0 and having a cross-machine direction wet tensile strength of from about 75 to about 200 grams (force) per 3 inches.
4. The tissue sheet of claim 1 , 2 or 3 wherein the geometric mean stiffness factor is from about 3.0 to about 6.0.
5. The tissue sheet of claim 1 , 2 or 3 wherein the geometric mean stiffness factor is from about 3.0 to about 5.0.
6. The tissue sheet of claim 1 , 2 or 3 wherein the geometric mean tensile energy is from about 90 to about 200 grams (force)-centimeter per centimeter.
7. The tissue sheet of claim 1 , 2 or 3 wherein the geometric mean tensile energy is from about 90 to about 190 grams (force)-centimeter per centimeter.
8. The tissue sheet of claim 1 , 2 or 3 having a burst strength of from about 200 to about 400 grams (force).
9. The tissue sheet of claim 1 , 2 or 3 having a burst strength of from about 300 to about 400 grams (force).
10. The tissue sheet of claim 1 , 2 or 3 having a Slough/Lint Test value of from about 1 to about 6 milligrams.
11. The tissue sheet of claim 1 , 2 or 3 having a Slough/Lint Test value of from about 1 to about 5 milligrams.
12. The tissue sheet of claims 1 , 2 or 3 having a ratio of the geometric mean tensile strength of at least one outer layer to the geometric mean tensile strength of at least one inner layer of from about 1.5 to about 3.0.
13. The tissue sheet of claims 1 , 2 or 3 having a ratio of the geometric mean tensile strength of at least one outer layer to the geometric mean strength of at least one inner layer of about 2.0 to about 3.0.
14. The tissue sheet of claims 1 , 2 or 3 having a ratio of the geometric mean tensile strength of both outer layers to the geometric mean tensile strength of at least one inner layer of from about 2.0 to about 3.0.
15. The tissue sheet of claims 1 , 2 or 3 having a cross-machine direction wet tensile strength of from about 75 to about 150 grams (force) per 3 inches.
16. The tissue sheet of claims 1 , 2 or 3 having a cross-machine direction wet tensile strength of from about 90 to about 130 grams (force) per 3 inches.
17. The tissue sheet of claims 1 , 2 or 3 having a CD wet/dry ratio of from about 0.1 to about 0.15 or less.
18. The tissue sheet of claims 1 , 2 or 3 having a CD wet/dry ratio of from about 0.1 to about 0.2.
19. The tissue sheet of claims 1 , 2 or 3 having a cross-machine direction stretch of from about 10 to about 20 percent.
20. The tissue sheet of claims 1 , 2 or 3 having a cross-machine direction stretch of from about 15 to about 20 percent.
21. The tissue sheet of claim 1 , 2 or 3 having a geometric mean surface roughness of from about 2 to about 8 microns.
22. The tissue sheet of claim 1 , 2 or 3 having a geometric mean surface roughness of from about 3 to about 7 microns.
23. The tissue sheet of claim 1 , 2 or 3 having a dry cross-machine direction tensile strength of from about 100 to about 250 grams (force) per centimeter.
24. The tissue sheet of claim 1 , 2 or 3 having a dry cross-machine direction tensile strength of from about 130 to about 200 grams (force) per centimeter.
25. The tissue sheet of claims 1 , 2 or 3 wherein both outer layers contain a bonding agent.
26. The tissue sheet of claims 1 , 2 or 3 having a topically-applied softening agent.