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Claims  |
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As our invention, we claim:
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
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