Unitary fluid acquisition, storage, and wicking material
View Patent ↗Disclosed is a unitary absorbent structure including a fluid acquisition stratum; a fluid distribution stratum; and a fluid storage stratum between the acquisition stratum and the distribution stratum. Each of the acquisition, distribution, and storage strata are in fluid communication with each other.
1. A unitary absorbent structure comprising:
(a) a fluid acquisition stratum having a basis weight of from 20 to 120 gsm comprising cellulosic fibers and a binder;
(b) a fluid distribution stratum having a basis weight of from 20 to 200 gsm comprising cellulose fibers and a binder; and
(c) a fluid storage stratum between the acquisition stratum and the distribution stratum, having a basis weight of from 60 to 400 gsm, wherein the acquisition stratum is coextensively contiguous with and in direct fluid communication with the storage stratum, the storage stratum is coextensively contiguous with and in direct fluid communication with the distribution stratum, the acquisition stratum and the distribution stratum are in indirect fluid communication, and the average pore size of each stratum decreases in a gradient in the direction from the acquisition stratum to the distribution stratum.
2. The unitary absorbent structure of claim 1 , wherein the cellulosic fiber of the fluid acquisition stratum (a) is fluff cellulose, modified fluff cellulose or a mixture thereof.
3. The unitary absorbent structure of claim 1 , wherein the fluid storage stratum (b) includes from 10 weight percent to 75 weight percent superabsorbent polymer.
4. The unitary absorbent structure of claim 1 , wherein the average resiliency of each stratum decreases in a gradient in the direction from the acquisition stratum to the distribution stratum.
5. The unitary absorbent structure of claim 1 , wherein the acquisition stratum contains an aqueous latex binder resin, bicomponent fibers or a mixture thereof.
6. The unitary absorbent structure of claim 1 , wherein the binder in the acquisition stratum is latex.
7. The unitary absorbent structure of claim 1 , wherein the binder in the acquisition stratum is selected from the group consisting of bicomponent fibers, polyolefin powder, and mixtures thereof.
8. The unitary absorbent structure of claim 1 , wherein the storage and distribution stratums each contain thermoplastic bonding fibers.
9. The unitary absorbent structure of claim 1 , wherein the storage stratum comprises cellulosic fibers and superabsorbent polymer.
10. The unitary absorbent structure of claim 1 , wherein the storage stratum comprises cellulosic fibers that have been modified to increase the curl and/or stiffness of the fibers.
11. The unitary absorbent structure of claim 1 , wherein the average pore size of the distribution stratum is less than the average pore size of either the acquisition or storage strata.
12. The unitary absorbent structure of claim 1 , wherein the average pore size of the distribution stratum is less than one half the average pore size of the acquisition and storage strata.
13. The unitary absorbent structure of claim 1 , wherein the distribution stratum comprises cellulosic fibers that have been modified to decrease the stiffness of the fibers.
14. The unitary absorbent structure of claim 1 , further comprising a tissue layer in contact with the surface of the distribution stratum that faces opposite to the storage stratum.
15. A diaper incorporating the unitary absorbent structure of claim 1 .
16. A feminine hygiene pad incorporating the unitary absorbent structure of claim 1 .
17. An adult incontinence pad incorporating the unitary absorbent structure of claim 1 .
18. A unitary absorbent structure comprising:
(a) a top fluid acquisition stratum comprising synthetic fibers and a binder;
(b) an upper middle fluid acquisition stratum comprising cellulosic fibers and a binder, where the top fluid acquisition stratum and the upper middle fluid acquisition stratum together have a basis weight of from 20 to 120 gsm;
(c) a fluid distribution stratum having a basis weight of from 20 to 200 gsm comprising cellulose fibers and a binder; and
(d) a fluid storage stratum between the acquisition stratum and the distribution stratum, having a basis weight of from 60 to 400 gsm, wherein the acquisition stratum is coextensively contiguous with and in direct fluid communication with the storage stratum, the storage stratum is coextensively contiguous with and in direct fluid communication with the distribution stratum, the acquisition stratum and the distribution stratum are in indirect fluid communication, and the average pore size of each stratum decreases in a gradient in the direction from the acquisition stratum to the distribution stratum.