US4500585A
Expired / Lapsed
US
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Creped absorbent composites
Assignee: Dow Chemical Co
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Filing: 1982-05-03
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Granted: 1985-02-19
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Expires: 2002-05-03
Abstract
Abstract Creped absorbent composites made from lightly crosslinked or water-swellable hydrophilic polymers with layers of wicking substrates are disclosed. The creped composites are made by drying the composites to less than 8% moisture and creping them in a creping zone. The creped composites have a tissue-like feel at low relative humidities with rapid absorption and are useful to make low bulk, high fluid capacity personal care products. Absorbent pads made from the above composites are also disclosed wherein the pads comprise one or more layers of wicking substrates, a water impermeable bottom sheet, and a water permeable face sheet.
Inventors
- 👤 Robert E. Erickson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:29
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; A61L15/425; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24446; Y10T428/24455; Y10T428/24463; Y10T428/249921; Y10T428/249953; Y10T428/249955; Y10T428/249958
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
82 words
A creped hydrophilic absorbent composite which has a rapid absorption rate and has a soft hand at low relative humidities which comprises the product produced by (a) reducing the moisture content of a composite of a water-swellable hydrophilic polymer with wicking substrates to less than 8% by weight by passing said composite through a drying zone, and (b) passing said dried composite through a creping zone wherein said polymer is fractured and broken into pieces which remain essentially laminated to said substrates.
Claim 2
Dependent Claim
82 words
A creped hydrophilic absorbent composite which has a rapid absorption rate and has a soft hand at low relative humidities which comprises the product produced by (a) reducing the moisture content of a composite of a water-swellable hydrophilic polymer with wicking substrates to less than 8% by weight by passing said composite through a drying zone, and (b) passing said dried composite through a creping zone wherein said polymer is fractured and broken into pieces which remain essentially laminated to said substrates.
Claim 3
Dependent Claim
49 words
The composite as set forth in claim 1 wherein the hydrophilic composite before being creped comprises a composite of a wicking substrate bonded to a hydrophilic polymer wherein the polymer is in a form selected from the group consisting of a film, a random fiber mat, and a powder.
Claim 4
Dependent Claim
25 words
The composite of claim 2 wherein said polymer comprises an aerated film having a density ranging from about 1.1 to 0.3 grams per cubic centimeter.
Claim 5
Dependent Claim
26 words
The composite of claim 1 wherein said wicking substrate is selected from the group consisting of woven fabrics, paper tissues non-woven fiber mats and polymeric foams.
Claim 6
Dependent Claim
29 words
An absorbent pad which comprises the absorbent composite of claim 1, one or more layers of wicking substrates, a water impermeable bottom sheet and a water permeable face sheet.
Claim 7
Dependent Claim
23 words
The absorbent pad of claim 5 wherein said water impermeable bottom sheet is polyethylene and said face sheet is a non-woven fiber mat.
Claim 8
Dependent Claim
68 words
A process for making the creped composite of claim 1 which comprises (a) reducing the moisture content of a composite of a water-swellable hydrophilic polymer with wicking substrates to less than 8% by weight by passing said composite through a drying zone, and (b) passing said dried composite through a creping zone wherein said polymer breaks into a plurality of pieces which remain essentially laminated to said substrates.
Claim 9
Dependent Claim
19 words
The process of claim 7 wherein said composite has a moisture content in the range from 1 to 6%.
Claim 10
Dependent Claim
16 words
The process of claim 7 wherein the water-swellable hydrophilic polymer is a lightly crosslinked carboxylic polyelectrolyte.
Claim 11
Dependent Claim
17 words
The process of claim 7 wherein the water-swellable hydrophilic polymer is in the form of a film.
Claim 12
Dependent Claim
25 words
The process of claim 10 wherein the film comprises an aerated film having a density ranging from about 1.1 to 0.3 grams per cubic centimeter.
Claim 13
Dependent Claim
83 words
A creped hydrophilic absorbent composite which has a rapid absorption rate and has a soft hand at low relative humidities which comprises the product produced by (a) reducing the moisture content of a composite of a lightly crosslinked carboxylic polyelectrolyte with wicking substrates to less than 8% by weight by passing said composite through a drying zone, and (b) passing said dried composite through a creping zone wherein said polyelectrolyte is fractured and broken into pieces which remain essentially laminated to said substrates.
Claim 14
Dependent Claim
83 words
A creped hydrophilic absorbent composite which has a rapid absorption rate and has a soft hand at low relative humidities which comprises the product produced by (a) reducing the moisture content of a composite of a lightly crosslinked carboxylic polyelectrolyte with wicking substrates to less than 8% by weight by passing said composite through a drying zone, and (b) passing said dried composite through a creping zone wherein said polyelectrolyte is fractured and broken into pieces which remain essentially laminated to said substrates.
Claim 15
Dependent Claim
51 words
The composite as set forth in claim 1 wherein the hydrophilic composite before being creped comprises a composite of a wicking substrate bonded to a lightly crosslinked carboxylic polyelectrolyte wherein the polyelectrolyte is in a form selected from the group consisting of a film, a random fiber mat, and a powder.
Claim 16
Dependent Claim
25 words
The composite of claim 13 wherein the film comprises an aerated film having a density ranging from about 1.1 to 0.3 grams per cubic centimeter.
Claim 17
Dependent Claim
26 words
The composite of claim 12 wherein said wicking substrate is selected from the group consisting of woven fabrics, paper tissues non-woven fiber mats and polymeric foams.
Claim 18
Dependent Claim
29 words
An absorbent pad which comprises the absorbent composite of claim 12, one or more layers of wicking substrates, a water impermeable bottom sheet and a water permeable face sheet.
Claim 19
Dependent Claim
23 words
The absorbent pad of claim 16 wherein said water impermeable bottom sheet is polyethylene and said face sheet is a non-woven fiber mat.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |