Claims
- 1. An absorbent structure comprising:
- a generally planar fibrous capillary substrate; and
- at least one site of an in situ polymerized osmotic absorbent hydrogel polymer having a proximal end joined to said fibrous capillary substrate, said osmotic absorbent hydrogel polymer further having a distal end freestanding from said capillary substrate, whereby said distal end can expand without constraint from said substrate upon imbibing liquids,
- said fibrous capillary substrate comprising regions of two different densities, an essentially continuous network high density region and a plurality of discrete low density regions, wherein said sites of the osmotic absorbent hydrogel polymer are disposed on said low density regions.
- 2. An absorbent structure comprising:
- a generally planar fibrous capillary substrate defining an X-Y plane and a Z-direction orthogonal thereto; and
- at least one site of an in situ polymerized freestanding osmotic absorbent hydrogel polymer joined to said fibrous capillary substrate and extending outwardly therefrom in the Z-direction whereby at least one said site of freestanding osmotic absorbent hydrogel polymer can expand in the X-Y plane without constraint from said substrate upon imbibing liquids,
- said fibrous capillary substrate comprising regions of two different densities, an essentially continuous network high density region and a plurality of discrete low density regions, wherein said sites of the osmotic absorbent hydrogel polymer are disposed on said low density regions.
- 3. An absorbent structure according to claim 2 wherein said osmotic absorbent hydrogel polymer is distributed on said fibrous capillary substrate and joined thereto in a plurality of discrete sites and said fibrous capillary substrate comprises an essentially continuous network in which said sites are disposed.
- 4. An absorbent structure according to claim 2 wherein at least one said site of the freestanding osmotic absorbent hydrogel polymer is joined to said fibrous capillary substrate at a proximal end of said site of osmotic absorbent hydrogel polymer, and has interfiber penetration of said fibrous capillary substrate at said proximal end.
- 5. An absorbent structure according to claim 1 wherein at least one said site of the freestanding osmotic absorbent hydrogel polymer is joined to said fibrous capillary substrate at a proximal end, and has interfiber penetration of said fibrous capillary substrate at said proximal end.
- 6. An absorbent structure comprising a generally planar fibrous capillary substrate and at least one site of an osmotic absorbent hydrogel polymer joined thereto, said absorbent structure made by the process comprising the steps of:
- providing a generally planar fibrous capillary substrate;
- providing a liquid precursor;
- increasing the kinematic viscosity of said liquid precursor to at least 2,000 centipoise;
- disposing said liquid precursor on said substrate in at least on discrete site; and
- in situ polymerizing said liquid precursor to form at least one discrete site of an osmotic absorbent hydrogel polymer joined to said substrate at a proximal end of said discrete site of said osmotic absorbent hydrogel polymer and having a distal end freestanding from said substrate, whereby said distal end can expand without constraint from said substrate upon imbibing liquids.
- 7. An absorbent structure made according to the process of claim 6 wherein said step of increasing said kinematic viscosity comprises the step of adding a thickening agent to said liquid precursor.
- 8. An absorbent structure made according to the process of claim 6 wherein said step of increasing said kinematic viscosity comprises partially prepolymerizing said liquid precursor.
Parent Case Info
This is a continuation-in-part of application Ser. No. 08/456,882, filed on Jun. 1, 1995, now abandoned, which is a continuation application of Ser. No. 08/155,040, filed Nov. 18, 1993, now abandoned.
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Continuations (1)
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Parent |
155040 |
Nov 1993 |
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Continuation in Parts (1)
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456882 |
Jun 1995 |
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