US 2003/0190852 A1 · High-performance absorbent structure

Abstract

Disclosed is an absorbent structure having wet integrity higher than about 4.0 kN/gsm, softness higher than 8.0/J, pliability higher than about 70/N, and providing a substantially dry liquid-accepting surface after receiving a quantity of liquid. The structure includes an upper ply having an upper fluid receiving surface and a lower surface and including (i) a top stratum including synthetic matrix fibers bonded with a binder, the matrix fibers having length from about 2 to about 15 mm; (ii) a middle stratum in fluid communication with the top stratum, the middle stratum including natural fibers, superabsorbent particles and a binder; and (iii) a bottom stratum in fluid communication with the middle stratum, the bottom stratum including natural fibers and a binder. The structure also includes a lower ply in fluid communication with the upper ply, the lower ply having an upper surface and a lower surface and including at least one stratum including natural fibers, superabsorbent polymer particles, and a binder, wherein the lower surface of the upper ply has a surface area less than about 80% of the upper surface area of the lower ply.

Drawings

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Drawings

Claims79

Dependent claims

An absorbent structure having wet integrity higher than about 4.0 kN/gsm, softness higher than 8.0/J, pliability higher than about 70/N, and providing a substantially dry liquid-accepting surface after receiving a quantity of liquid, said structure comprising:

a) an upper ply having an upper fluid receiving surface and a lower surface and comprising:
i) a top stratum comprising synthetic matrix fibers bonded with a binder, said matrix fibers having length from about 2 to about 15 mm;
ii) a middle stratum in fluid communication with the top stratum, the middle stratum including natural fibers, superabsorbent particles and a binder;
and
iii) a bottom stratum in fluid communication with the middle stratum, the bottom stratum including natural fibers and a binder;
and
b) a lower ply in fluid communication with the upper ply, the lower ply having an upper surface and a lower surface and including at least one stratum including natural fibers, superabsorbent polymer particles, and a binder,
wherein the lower surface of the upper ply has a surface area less than about 80% of the upper surface area of the lower ply;
c) the basis weight of the top stratum of the upper ply is from about 20 gsm to about 120 gsm;
d) the binder content (percent by weight) in the top stratum of the upper ply is from about 5% to about 20%;
c) the basis weight of the middle stratum of the upper ply is from about 50 gsm to about 1000 gsm;
f) the binder content (percent by weight) in the middle stratum of the upper ply is from about 1% to about 10%;
g) the basis weight of the bottom stratum of the upper ply is from about 10 gsm to about 150 gsm;
h) the binder content (percent by weight) in the bottom stratum of the upper ply is from about 5% to about 15%;
i) the superabsorbent particle content (percent by weight) in the upper ply is lower than the content of superabsorbent particles in the lower ply;
j) apparent density of the upper ply is lower than the apparent density of the lower ply;
k) the basis weight of the lower ply is from about 100 gsm to about 1000 gsm;
l) apparent density of the lower ply is about 0.15 g/cc to about 0.25 g/cc;
m) the binder content (percent by weight) in the lower ply is from about 1% to about 8%;
and
n) the lower ply contains at least 30% superabsorbent particles of the basis weight of the lower ply.

18 more elements

a) an upper ply having an upper fluid receiving surface and a lower surface comprising:
i) a top stratum including synthetic matrix fibers bonded with a binder, said matrix fibers having length of from about 2 to about 15 mm;
ii) a middle stratum in fluid communication with the top stratum, the middle stratum including natural fibers and superabsorbent polymer particles;
and
iii) a bottom stratum in fluid communication with the middle stratum, including natural fibers and a binder;
b) and a lower ply in fluid communication with the upper ply, the lower ply having an upper surface and a lower surface and including:
i) a top stratum including natural fibers and a binder;
and
ii) a bottom stratum including natural fibers, superabsorbent polymer particles, and a binder,
wherein:
a) the lower surface of the upper ply has a surface area less than about 80% of the upper surface area of the lower ply;
b) the top stratum of the upper ply exhibits essentially no fluid wicking capability;
c) the basis weight of the top stratum of the upper ply is from about 20 gsm to about 120 gsm;
d) the binder content (percent by weight) of the top stratum of the upper ply is from about 5%-to about 20%;
e) the basis weight of the middle stratum of the upper ply is from about 50 gsm to about 1000 gsm;
f) the binder content (percent by weight) of the middle-stratum of the upper ply is from about 1% to about 10%;
g) the basis weight of the bottom stratum of the upper ply is from about 10 gsm to about 150 gsm;
h) the binder content (percent by weight) of the bottom stratum of the upper ply is from about 5% to about 15%;
i) the content of superabsorbent particles in the upper ply is lower than the content of superabsorbent particles in the lower ply;
j) the lower ply contains at least 30% superabsorbent particles based on the total basis weight of the lower ply;
k) the top stratum of the lower ply contains from about 0% to about 20% superabsorbent particles based on the basis weight of the top stratum of the lower ply;
l) the basis weight of the lower ply is from about 100 gsm to about 1000 gsm;
m) the apparent density of the lower ply is about 0.15 g/cc to about 0.25 g/cc;
n) the apparent density of the upper ply is lower than the apparent density of the lower ply;
and
o) the binder content (percent by weight) of the lower ply is from about 1% to about 8%.

23 more elements

An absorbent structure comprising:

a) an upper ply including:
i) a top stratum including polyester matrix fibers bonded with latex in an amount of 15 to 25% by weight of said top stratum, said matrix fibers having length from about 4 mm to about 8 mm and having thickness from about 9 to about 15 denier per fiber, the basis weight of said top stratum being from about 40 to about 60 gsm;
ii) a middle stratum in fluid communication with the top stratum, the middle stratum including softwood fluff, superabsorbent polymer particles, and binder fiber, the content of the superabsorbent polymer particles being from about 30 to 40% of the basis weight of the said middle stratum, the content of the binder fibers being from about 6 to about 12% of the basis weight of the said middle stratum, and the basis weight of the said middle stratum being from about 150 to about 200 gsm;
iii) a bottom stratum in fluid communication with the middle stratum, including softwood fluff and binder fibers, the content of the binder fibers being from about 8 to about 16% of the basis weight of the said bottom stratum, and the basis weight of the said bottom stratum being from about 60 to about 120 gsm;
and
b) a lower ply in fluid communication with the upper ply, the lower ply comprising:
i) a top stratum including softwood fluff and binder fibers, the content of the binder fibers being from about 10 to about 25% of the basis weight of the said top stratum, and basis weight being from about 20 to about 60 gsm;
ii) a bottom stratum including softwood fluff, superabsorbent polymer particles, and binder fibers, the content of the superabsorbent polymer particles being from about 50 to about 80% of the basis weight of the said bottom stratum, the content of the binder fibers being from about 2 to 5% of the basis weight of the said bottom stratum;
and
iii) cellulose tissue upon which the lower ply has been formed,
wherein:
a) the upper ply has a surface area adjacent to the lower ply, said surface area being from about 40 to 60% of the facing surface area of the lower ply;
b) the density of the upper ply is from about 0.05 to about 1.0 g/cc;
c) the density of the lower ply is from about 0.15 to about 0.3 g/cc.

11 more elements

An absorbent structure comprising:

a) an upper ply containing:
i) a top stratum including polyester matrix fibers bonded with latex in an amount of 15 to 25% by weight of said top stratum, said matrix fibers having length from about 4 mm to about 8 mm and having thickness from about 9 to about 15 denier per fiber, the basis weight of said top stratum being from about 40 to about 60 gsm;
ii) a middle stratum in fluid communication with the top stratum, the middle stratum including softwood fluff, superabsorbent polymer particles, and binder fiber, the content of the superabsorbent polymer particles being from about 40 to 60% of the basis weight of the said middle stratum, the content of the binder fibers being from about 6 to about 12% of the basis weight of the said middle stratum, and the basis weight of the said middle stratum being from about 200 to about 280 gsm;
iii) a bottom stratum in fluid communication with the middle stratum, including softwood fluff and binder fibers, the content of the binder fibers being from about 8 to about 16% of the basis weight of the said bottom stratum, and the basis weight of the said bottom stratum being from about 60 to about 120 gsm;
and
b) a lower ply in fluid communication with the upper ply, the lower ply comprising:
i) a top stratum including softwood fluff and binder fibers, the content of the binder fibers being from about 10 to about 25% of the basis weight of the said top stratum, and basis weight being from about 20 to about 60 gsm;
ii) a bottom stratum including softwood fluff, superabsorbent polymer particles, and binder fibers, the content of the superabsorbent polymer particles being from about 40 to about 60% of the basis weight of the said bottom stratum, the content of the binder fibers being from about 2 to 5% of the basis weight of the said bottom stratum, and the basis weight of the said bottom stratum being from about 200 to about 350 gsm;
and
iii) cellulose tissue upon which the lower ply has been formed, wherein:
c) the upper ply has a surface area adjacent to the lower ply, said surface area being from about 40 to 60% of the facing surface area of the lower ply;
d) the density of the upper ply is from about 0.05 to about 1.0 g/cc;
e) the density of the lower ply is from about 0.15 to about 0.3 g/cc.

10 more elements

Dependencies are inferred from the claim text.

Description9,377 words

Summary1,082 words

#The present invention relates to high-capacity, thin and highly conformable absorbent structures, useful in absorbent articles including baby diapers, adult incontinence products, sanitary napkins and the like. More particularly, the present invention relates to absorbent structures containing matrix fibers, binders and superabsorbent polymers, the structure having an x-directional fluid storage profile.

#Absorbent structures are important in a wide range of disposable absorbent articles including baby diapers, adult incontinence products, sanitary napkins and the like.

#These and other absorbent articles are generally provided with an absorbent core to receive and retain body liquids. The absorbent core is usually sandwiched between a liquid pervious topsheet, whose function is to allow the passage of fluid to the core and a liquid impervious backsheet whose function is to contain the fluid and to prevent it from passing through the absorbent article to the garment of the wearer of the absorbent article.

Brief description of the drawings3 figures

#FIG. 1 depicts an absorbent structure of the invention comprising an upper absorbent ply and a lower absorbent ply.

#FIG. 2 is a schematic representation of a modified clamp used in a Gurley tester.

#FIG. 3 depicts a schematic representation of the apparatus for measuring softness.

Detailed description8,249 words

#All references cited in this application are hereby fully incorporated by reference. In case of conflict in terminology, the present disclosure controls.

#The present invention includes an absorbent structure of at least two plies of bonded absorbent material, wherein the plies are in fluid communication with each other. With reference to FIG. 1, the structure includes: (a) a shorter, upper ply 2 having three strata 6, 8 and 10; and (b) a longer, lower absorbent ply 4. In general, the surface area of the bottom surface of upper ply 2 is less than 80% of the surface area of the upper surface of lower ply 4. This arrangement has an advantage over single-ply core structures by allowing for better containment and usage of the absorbent material during use of the absorbent article by the user.

#The advantage obtained by providing a two ply structure as described above, is that the fluid discharge from the human body occurs mainly over the frontal 16 and central 18 region of the absorbent core. The present invention places more of the absorbent capacity in the region where the liquid discharge insults the core. Further, the overall density of upper ply 2 is lower than the overall density of lower ply 4. This difference in densities allows for improved fluid acquisition and rewet performance since liquid is drawn from the upper ply to the lower ply due to the capillary tension gradient between the plies.

Facts

Application

10/436,659Filed 12 May 2003

Priority

11 Jan 1999

Published

9 Oct 2003

Term ends

Not estimatedThe source records don’t support an estimate.

Classification13 codes

B32B 27/02
Layered products comprising a layer of synthetic resin: in the form of fibres or filaments
A61F 13/535
Having an inhomogeneous composition through the thickness of the pad: inhomogeneous in the plane of the pad, e.g. core absorbent layers being of…
B32B 5/26
One layer being a fibrous or filamentary layer: another layer next to it also being fibrous or filamentary
B32B 27/04
Layered products comprising a layer of synthetic resin: as impregnant, bonding, or embedding substance

Family

Application60/116,036Us provisional application · filed 11 Jan 1999

Application09/475,850Continuation · filed 30 Dec 1999

Application10/436,659Continuation · filed 12 May 2003

US 2003/0012919 A1Published application

US 6,562,742 B2Related patent

US 7,176,149 B2Related patent

US 2003/0190852 A1This patent

From the US filing history. Foreign family members aren’t listed.

Timeline

11 Jan 1999Priority claimedParent application 60/116,036
12 May 2003Application filedUS 10/436,659
9 Oct 2003PublishedUS 2003/0012919 A1
19 Nov 2003Assigned to Fleet National Bankrelease of security interest
13 Jul 2007Assigned to Buckeye Technologies Inc.merger
3 Aug 2007Assigned to Bank of America, N.A., AS Collateral Agentnotice of grant of security interest
13 Aug 2007Assigned to Bki Holding Corporationassignment of assignor's interest
13 Aug 2007Assigned to Bki Holding Corporationassignment of assignor's interest
20 Jul 2023Assigned to Buckeye Technologies Inc.release of security interest

High-performance absorbent structure

Life of this patent

High-performance absorbent structure

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims79

Description9,377 words

Drawings

Classification13 codes

Life of this patent

Description9,377 words