Claims
- 1. A multi-ply tissue product comprising at least two foam-formed plies incorporating at least about 100 ppm of forming-loop-incorporated surfactant, each said ply comprising:
- from at least about 50% by weight to about 80% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 m of fiber length (mg/100 m);
- from at least about 20% by weight to about 50% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof: said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three-dimensional anfractuous character;
- said plies being embossed together to an emboss depth of at least about 0.020 inch, the percent loss in total dry breaking tensile strength upon embossing of the tissue being no more than about 80% of the percent loss in total dry breaking tensile strength upon embossing plies of a comparable conventional water formed tissue having the same structure, fiber composition, basis weight and unembossed total dry breaking tensile strength to the same emboss depth using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of said multi-ply tissue product;
- each said ply having a basis weight of from about 4 to about 20 pound per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 2. The multi-ply tissue product of claim 1, wherein the surface root mean square roughness of each of said foam formed plies of the tissue is no more than about 0.018 mm.
- 3. The multi-ply tissue product of claim 1, wherein the surface root mean square roughness of each of said foam formed plies of the tissue is no more than about 0.020 mm and wherein the Kajaani formation Index of the foam formed ply is at least about 75.
- 4. The multi-ply tissue product of claim 1, wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 5. The multi-ply tissue product of claim 1, wherein of said hardwood fibers in said foam formed plies, at least about 50% by weight thereof are eucalyptus fibers.
- 6. The multi-ply tissue product of claim 1, wherein the percentage of hardwood fibers in each of said foam formed plies is at least about 75% by weight and wherein the surface root mean square roughness of the unembossed area of each of said foam formed plies of the tissue is no more than about 0.018 mm and wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 7. The multi-ply tissue product of claim 1, wherein the percentage of hardwood fibers in each of said foam formed plies is at least about 60% by weight.
- 8. The multi-ply tissue product of claim 7, wherein each of said foam formed plies of tissue has a Kajaani Formation Index of at least about 80, a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 13 grams @ 50 g/in, and wherein the surface root mean square roughness of the unembossed area of each of said foam formed plies is no more than about 0.018 mm.
- 9. The multi-ply tissue product of claim 8, wherein each of said foam formed plies has a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 75 grams per pound per 3000 sq. ft. ream per 3-inch width, a stiffness modulus of no more than about 16 grams @ 50 g/in, and a hardwood content of at least about 75% by weight.
- 10. The multi-ply tissue product of claim 9, wherein the geometric mean deviation in the coefficient of friction of the surface of each of said foam formed plies is no more than about 0.013 and wherein the stiffness modulus of said multi-ply tissue is no more than about 16 grams @ 50 g/in.
- 11. The multi-ply tissue product of claim 10, wherein each of said foam formed plies is a calendered ply having a geometric mean deviation in the coefficient of friction of the surface of said foam formed ply of no more than about 0.009 and wherein the stiffness modulus is no more than about 25 grams @ 50 g/in.
- 12. An embossed, biological membrane contact compatible, multi-ply tissue product comprising at least one foam-formed ply of tissue incorporating at least about 100 ppm of forming-loop-incorporated surfactant and having at least two strata defined therein, at least one exterior stratum of said foam-formed ply comprising:
- from at least about 60% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- no more than about 40% by weight of relatively long, strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- at least one other stratum of said foam-formed ply comprising:
- no more than about 35% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- at least about 60% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, and a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three-dimensional anfractuous character;
- said foam formed ply of tissue having: a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3-inch width,
- said embossed tissue being embossed with a nested pattern to a depth of at least about 0.020 inch over at least about 10% of its area and exhibiting a percent loss in total dry breaking tensile strength upon embossing of no more than about 80% of the percent loss in total dry breaking tensile strength experienced upon embossing a like number of plies of a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of said embossed tissue comprising at least one foam formed ply;
- said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 13. The embossed tissue product of claim 12, being further characterized by a stiffness modulus no greater than about 25 grams @ 50 g/in; the root mean square roughness of at least one surface of said foam formed ply being no more than about 0.018 mm; and the geometric mean deviation in the coefficient of friction of the exterior surface of said foam formed ply being no more than about 0.009.
- 14. The embossed tissue product of claim 12, being further characterized by a stiffness modulus no greater than about 16 grams @ 50 g/in; the root mean square roughness of at least one surface of said foam formed ply being no more than about 0.020 mm; and the geometric mean deviation in the coefficient of friction of the exterior surface of said foam formed ply being no more than about 0.013.
- 15. The embossed tissue product of claim 12, wherein the surface of said exterior stratum of said foam formed ply has a root mean square roughness of no more than about 0.020 mm.
- 16. The embossed tissue product of claim 12, wherein the surface root mean square roughness of said exterior stratum of said foam formed ply of the tissue is no more than about 0.018 mm and wherein the Kajaani Formation Index of said foam formed ply is at least about 80.
- 17. The embossed tissue product of claim 12, wherein the plies of said multi-ply tissue product are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 18. The embossed tissue product of claim 12, said hardwood fibers in said foam formed ply, at least about 50% by weight thereof are eucalyptus fibers.
- 19. The embossed tissue product of claim 12, wherein the percentage of hardwood fibers in said exterior stratum of said foam formed ply is at least about 75% by weight by weight and wherein the surface root mean square roughness of the exterior stratum of said foam formed ply is no more than about 0.018 mm and wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 20. The embossed tissue product of claim 12, wherein the percentage of hardwood fibers in the exterior stratum of said foam formed ply is at least about 75% by weight.
- 21. The embossed tissue product of claim 12, wherein said foam formed ply of tissue has a Kajaani Formation Index of at least about 80, a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3-inch width, a stiffness modulus of no more than about 13 grams @ 50 g/in, and wherein the root mean square roughness of the exterior surface of said exterior stratum of the foam formed ply of the tissue is no more than about 0.018 mm.
- 22. The embossed tissue product of claim 21, wherein said foam formed ply has a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 75 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 16 grams @ 50 g/in, and a hardwood content of at least about 75% by weight.
- 23. The embossed tissue product of claim 22, wherein the geometric mean deviation in the coefficient of friction of the surface of said exterior stratum of said foam formed ply is no more than about 0.013 and wherein the stiffness modulus of said foam formed ply is no more than about 16 grams @ 50 g/in.
- 24. The embossed tissue product of claim 22, wherein said foam formed ply is a calendered ply having a geometric mean deviation in the coefficient of friction of the surface of said exterior stratum of said foam formed ply of no more than about 0.009 and wherein the stiffness modulus of said foam formed ply is no more than about 25 grams @ 50 g/in.
- 25. A multi-ply tissue product comprising at least two foam formed plies incorporating at least about 100 ppm of forming-loop-incorporated surfactant, each said ply comprising:
- from at least about 50% by weight to about 80% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood, said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 m of fiber length (mg/100 m);
- from at least about 20% by weight to about 50% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof, said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three-dimensional anfractuous character;
- said piles being nested embossed to an emboss depth of at least about 0.020 inch over at least about 10% of its area, the tissue product being capable one retaining at least about 70% of the total dry breaking tensile strength of the unembossed plies upon nested embossing to a depth of no more than about 0.060 in. over 16% of its area;
- said tissue product exhibiting a percent loss in total dry breaking tensile strength upon embossing of no more than about 80% of the percent loss in total dry breaking tensile strength experienced upon embossing plies of a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of the foam formed tissue; and
- each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 26. The multi-ply tissue product of claim 25, wherein the root mean square roughness of an exterior surface of one of the foam formed plies of the tissue is no more than about 0.020 mm.
- 27. The multi-ply tissue product of claim 25, wherein the root mean square roughness of an exterior surface of at least one of the foam formed plies of the tissue is no more than about 0.018 mm. and wherein the Kajaani Formation Index of said foam formed ply is at least about 80.
- 28. The multi-ply tissue product of claim 25, wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 29. The multi-ply tissue product of claim 28, wherein said foam formed plies of tissue have a Kajaani Formation Index of at least about 80, a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width a stiffness modulus of no more than about 13 grams @ 50 g/in, and wherein the root mean square roughness of an exterior surface of least one foam formed ply of the tissue is no more than about 0.018 mm.
- 30. The multi-ply tissue product of claim 29, wherein said at least one foam formed ply has a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 100 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 20 grams @ 50 g/in.
- 31. The multi-ply tissue product of claim 30, wherein the geometric mean deviation in the coefficient of friction of an exterior surface of said at least one foam formed ply is no more than about 0.013 and wherein the stiffness modulus thereof is no more than about 16 grams @ 50 g/in.
- 32. The multi-ply tissue product of claim 31, wherein said at least one foam formed ply is a calendered ply having a geometric mean deviation in the coefficient of friction of the exterior surface of said at least one foam formed ply of no more than about 0.009 and wherein the stiffness modulus thereof is no more than about 25 grams @ 50 g/in.
- 33. An embossed, foam-formed, biological membrane contact compatible, tissue product comprising at least three plies of tissue, at least one foam formed exterior ply of the product comprising:
- at least about 100 ppm of forming-loop-incorporated surfactant,
- from at least about 60% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- no more than about 40% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm., a coarseness of about 14 to about 28 mg/100 m;
- said one ply of tissue having a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width, a root mean square roughness of no more than about 0.020 mm; and at least one other ply comprising:
- no more than about 25% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- at least about 60% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber, and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three dimensional anfractuous character;
- said other ply of tissue having a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 100 grams per pound per 3000 sq. ft. ream per 3-inch width, said embossed tissue product being point-to-point embossed to a depth of at least about 0.030 inch over at least about 10% of its area and exhibiting a percent loss in total dry breaking tensile strength upon embossing of no more than about 80% of the percent loss in total dry breaking tensile strength experienced upon embossing plies of a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of the tissue product and being characterized by a perceptible softness no less than that of said comparable conventional water formed tissue, each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 34. The embossed tissue product of claim 33, wherein said one ply is further characterized: by a stiffness modulus no greater than about 25 grams @ 50 g/in.; the root mean square roughness of at least one surface of said one foam formed ply being no more than about 0.018 mm; and the geometric mean deviation in the coefficient of friction of the exterior surface of said one foam formed ply being no more than about 0.009.
- 35. The embossed tissue product of claim 33, wherein said one ply is further characterized by a stiffness modulus no greater than about 16 grams @ 50 g/in; the root mean square roughness of at least one surface of said one foam formed ply being no more than about 0.020 mm; and the geometric mean deviation in the coefficient of friction of the exterior surface of said one foam formed ply being no more than about 0.013.
- 36. The embossed tissue product of claim 33, wherein the exterior surface of said one foam formed ply of the tissue has a root mean square roughness of no more than about 0.020 mm.
- 37. The embossed tissue product of claim 33, wherein the surface root mean square roughness of said exterior surface of said one foam formed ply of the tissue is no more than about 0.018 mm and wherein the Kajaani Formation Index of said one foam formed ply is at least about 80.
- 38. The embossed tissue product of claim 33, wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 39. The embossed tissue product of claim 33, wherein of said hardwood fibers in said foam formed ply, at least about 50% by weight thereof are eucalyptus fibers.
- 40. The embossed tissue product of claim 33, wherein the percentage of hardwood fibers in said exterior surface of said one foam formed ply is at least about 75% by weight and wherein the surface root mean square roughness of the exterior surface of said one foam formed ply of the tissue is no more than about 0.018 mm and wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 41. The embossed tissue product of claim 33, wherein the percentage of hardwood fibers in said one foam formed ply is at least about 75% by weight.
- 42. The embossed tissue product of claim 33, wherein said one foam formed ply of tissue has a Kajaani Formation Index of at least about 80, a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 13 grams @ 50 g/in, and wherein the root mean square roughness of the exterior surface of said one foam formed ply of the tissue is no more than about 0.018 mm.
- 43. The embossed tissue product of claim 42, wherein said one foam formed ply has a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 75 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 16 grams @ 50 g/in, and a hardwood content of at least about 75% by weight.
- 44. The embossed tissue product of claim 43, wherein the geometric mean deviation in the coefficient of friction of the surface of said exterior one foam formed ply is no more than about 0.013 and wherein the stiffness modulus of said one foam formed ply is no more than about 16 grams @ 50 g/in.
- 45. The embossed tissue product of claim 44, wherein said one foam formed ply is a calendered ply having a geometric mean deviation in the coefficient of friction of the surface of said one foam formed ply of no more than about 0.009 and wherein the stiffness modulus of said one foam formed ply is no more than about 25 grams @ 50 g/in.
- 46. A tissue product comprising at least one foam formed embossed ply incorporating at least about 100 ppm of forming-loop-incorporated surfactant, said ply comprising:
- from at least about 50% by weight to about 80% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood, said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 m of fiber length (mg/100 m);
- from at least about 20% by weight to about 50% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof, said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three-dimensional anfractuous character;
- said ply being an embossed ply having an exterior surface, the emboss being to an emboss depth of at least about 0.030 inch over at least about 5% of the area of said tissue, the total embossed area being at least about 10% of the area of said tissue, the tissue product being capable of retaining at least about 70% of the total dry breaking tensile strength of an unembossed ply upon point-to-point embossing to a depth of no more than about 0.050 in. over 16% of its area;
- said tissue product exhibiting a percent loss in total dry breaking tensile strength upon embossing of no more than about 80% of the percent loss in total dry breaking tensile strength experienced upon embossing a ply of a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength to the same depth of emboss using the same embossing pattern, said water formed ply being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of the foam formed tissue; and
- said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 47. The tissue product of claim 46, wherein the root mean square roughness of said exterior surface of said one foam formed ply of the tissue is no more than about 0.020 mm.
- 48. The tissue product of claim 46, wherein the root mean square roughness of said exterior surface of said foam formed ply of the tissue is no more than about 0.018 mm and wherein the Kajaani Formation Index of said foam formed ply is at least about 80.
- 49. An embossed, biological membrane contact compatible, tissue product comprising at least two foam-formed plies of tissue, each having at least two strata defined therein, at least one exterior stratum of each ply comprising:
- at least about 100 ppm of forming-loop-incorporated surfactant;
- from at least about 60% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- no more than about 40% by weight of relatively long, strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- at least one other stratum of each said foam-formed ply comprising:
- no more than about 35% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- at least about 60% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, and a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three dimensional anfractuous character;
- each said foam formed ply of tissue having: a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width;
- said embossed tissue being embossed with a pattern to a depth of at least about 0.020 inch over at least about 10% of its area and exhibiting a percent loss in total dry breaking tensile strength upon embossing of no more than about 80% of the percent loss in total dry breaking tensile strength experienced upon embossing a like number of plies of a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of said embossed tissue comprising at least one foam formed ply, each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 50. The embossed tissue product of claim 49, being further characterized by a stiffness modulus no greater than about 25 grams @ 50 g/in; the root mean square roughness of at least one exterior stratum of one of said foam formed plies being no more than about 0.018 mm; and the geometric mean deviation in the coefficient of friction of said one exterior stratum being no more than about 0.009.
- 51. The embossed tissue product of claim 49, being further characterized by a stiffness modulus no greater than about 16 grams @ 50 g/in; the root mean square roughness of at least one exterior stratum of one of said foam formed plies being no more than about 0.020 mm; and the geometric mean deviation in the coefficient of friction of the exterior surface of said one exterior stratum being no more than about 0.013.
- 52. The embossed tissue product of claim 49, wherein the surface of said exterior strata of each foam formed ply of the tissue has a root mean square roughness of no more than about 0.020 mm.
- 53. The embossed tissue product of claim 49, wherein the surface root mean square roughness of said exterior stratum of each foam formed ply of the tissue is no more than about 0.018 mm and wherein the Kajaani Formation Index of each foam formed ply is at least about 80.
- 54. The embossed tissue product of claim 49, wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 55. The embossed tissue product of claim 49, wherein of said hardwood fibers in each said foam formed ply, at least about 50% by weight thereof are eucalyptus fibers.
- 56. The embossed tissue product of claim 49, wherein the percentage of hardwood fibers in said exterior strata of each said foam formed ply is at least about 75% by weight and wherein the surface root mean square roughness of the exterior strata of each foam formed ply of the tissue is no more than about 0.018 mm and wherein the plies are embossed together with a nested emboss having a depth of at least about 0.030 in.
- 57. The embossed tissue product of claim 49, wherein the percentage of hardwood fibers in the exterior strata of each said foam formed ply is at least about 75% by weight.
- 58. The embossed tissue product of claim 49, wherein each said foam formed ply of tissue has a Kajaani Formation Index of at least about 80, a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 13 grams @ 50 g/in, and wherein the root mean square roughness of the exterior surface of said exterior strata of each foam formed ply of the tissue is no more than about 0.018 mm.
- 59. The embossed tissue product of claim 58, wherein each said foam formed ply has a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 100 grams per pound per 3000 sq. ft. ream per 3 inch width, a stiffness modulus of no more than about 20 grams @ 50 g/in, and a hardwood content of at least about 75% by weight.
- 60. The embossed tissue product of claim 59, wherein the geometric mean deviation in the coefficient of friction of the surface of said exterior strata of each said foam formed ply is no more than about 0.013 and wherein the stiffness modulus of each said foam formed ply is no more than about 16 grams @ 50 g/in.
- 61. The embossed tissue product of claim 60, wherein each said foam formed ply is a calendered ply having a geometric mean deviation in the coefficient of friction of the surface of said exterior stratum of said foam formed ply of no more than about 0.009 and wherein the stiffness modulus of each said foam formed ply is no more than about 25 grams @ 50 g/in.
- 62. A multi-ply tissue product comprising at least two plies, at least one of which is a foam formed substantially homogeneous ply comprising:
- at least about 100 ppm of forming-loop-incorporated surfactant;
- from at least about 50% by weight to about 80% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- from at least about 20% by weight to about 50% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber, and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three-dimensional anfractuous character;
- said plies being embossed together to an emboss depth of at least about 0.030 inch, the surface of said foam formed ply possessing a perceptible improvement in softness in relation to the softness of comparable conventional water formed tissue having the same structure, fiber composition, basis weight and unembossed total dry breaking tensile strength, embossed to the same emboss depth using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of said multi-ply tissue product, each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 63. An embossed, foam-formed, biological membrane contact compatible, tissue product comprising at least three plies of tissue, at least one substantially homogeneous foam formed exterior ply of the product comprising:
- at least about 100 ppm of forming-loop-incorporated surfactant;
- from at least about 60% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- no more than about 40% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber, and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- said one ply of tissue having a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width, a root mean square roughness of no more than about 0.020 mm; and
- at least one other ply comprising:
- no more than about 20% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- at least about 60% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber, and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three dimensional anfractuous character;
- said other ply of tissue having a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 100 grams per pound per 3000 sq. ft. ream per 3 inch width, said embossed tissue product being point-to-point embossed to a depth of at least about 0.025 inch over at least about 10% of its area and exhibiting perceptibly improved softness relative to a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength, embossed to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of the tissue product; and
- each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 64. An embossed, biological membrane contact compatible, tissue product comprising at least two foam-formed plies of tissue, each incorporating at least about 100 ppm of forming-loop-incorporated surfactant and having at least two strata defined therein, at least one exterior stratum of each ply comprising:
- from at least about 60% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- no more than about 40% by weight of relatively long, strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber, and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- at least one other stratum of each said foam-formed ply comprising:
- no more than about 35% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- at least about 60% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm.,and a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk enhancing fibers having a three dimensional anfractuous character;
- each said foam formed ply of tissue having: a total dry breaking tensile strength (machine direction tensile strength plus cross direction tensile strength) of at least about 50 grams per pound per 3000 sq. ft. ream per 3 inch width;
- said embossed tissue being embossed with a pattern to a depth of at least about 0.020 inch over at least about 10% of its area and exhibiting a perceptible improvement in softness relative to a comparable conventional water formed tissue having the same structure, overall fiber composition, basis weight and unembossed total dry breaking tensile strength, embossed to the same depth of emboss using the same embossing pattern, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and unembossed total dry breaking tensile strength as the corresponding ply of said embossed tissue comprising at least one foam formed ply; and
- each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
- 65. A multi-ply tissue product comprising at least two plies, at least one of which is a foam formed ply comprising:
- at least about 100 ppm of forming-loop-incorporated surfactant;
- from at least about 50% by weight to about 80% by weight of relatively short, high softness cellulosic fiber formed by chemical pulping of hardwood; said fibers having a weight average fiber length of between about 0.5 to about 2.2 mm, a coarseness of about 7 to about 14 mg of fiber per 100 meters of fiber length (mg/100 m);
- from at least about 20% by weight to about 50% by weight of relatively long strength-enhancing cellulosic fiber chosen from the group consisting of chemically pulped softwood fiber and chemi-thermo-mechanically pulped softwood fiber and mixtures thereof; said strength-enhancing cellulosic fiber having a weight average fiber length of about 2 to about 4 mm, a coarseness of about 14 to about 28 mg/100 m;
- optionally, up to about 30% by weight of bulk-enhancing fibers having a three dimensional anfractuous character;
- said foam formed ply being calendered to a percent reduction in caliper of at least about 10%, the surface of said foam formed ply possessing a perceptible improvement in softness in relation to the softness of comparable conventional water formed tissue having the same structure, fiber composition, basis weight and uncalendered total dry breaking total tensile strength, calendered to the same reduction in caliper, each of said water formed plies being of the same fiber composition, basis weight, percent crepe and uncalendered total dry breaking tensile strength as the corresponding ply of said multi-ply tissue product; and
- each said ply having a basis weight of from about 4 to about 20 pounds per 3,000 sq. ft. ream; an 8 ply caliper to 3000 sq. ft. basis weight ratio exceeding about 3.7 mils/pound of basis weight, calculated based on the thickness of 8 plies in mils divided by the basis weight of a single ply of a 3,000 sq. ft. ream in pounds.
Parent Case Info
This application is a continuation of application Ser. No. 08/107,039, filed on Aug. 17, 1993, now abandoned, which is a continuation of application Ser. No. 07/641,656, filed on Jan. 15, 1991, now abandoned.
US Referenced Citations (7)
Non-Patent Literature Citations (1)
Entry |
"The Significance of Coarseness in Papermaking" Publication S20 02.0-E of Katjaani Elec., Ltd. (1986), pp. 1-12. |
Continuations (2)
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Number |
Date |
Country |
Parent |
107039 |
Aug 1993 |
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Parent |
641656 |
Jan 1991 |
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