US4182649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethane foam sheet and method
Assignee: WR Grace and Co
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Filing: 1977-02-11
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Granted: 1980-01-08
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Expires: 1997-02-11
Abstract
Abstract Disclosed herein is a composite, self-supporting, polyurethane foam sheet prepared by forming an aqueous dispersion of hydrophilic polyurethane foam particles with fibers to serve as a binder therefor, wet-layering the dispersion onto a supporting screen to form a sheet, and removing water from the sheet. If desired, a porous web, woven or non-woven, e.g. paper, cloth, etc., can be positioned on the screen with the dispersion being layered out onto the web to form a laminar composite structure. Whether in sheet form or as a laminar structure the product of the invention is formed rapidly and possesses a desirable soft or cushioning feel.
Inventors
- 👤 Irving E. Isgur
- 👤 Andrew B. Holmstrem
- 👤 Norman J. Hayes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:04
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/18; B32B5/20; B32B5/22; B32B5/24; D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/54; D21H17/57; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0278; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249986; Y10T428/25; Y10T428/254; Y10T428/29; Y10T428/2982; Y10T428/31504; Y10T428/31551; Y10T428/31562; Y10T428/31573; Y10T428/31587; Y10T428/31591; Y10T442/00; Y10T442/30; Y10T442/3325; Y10T442/60; Y10T442/647
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
174 words
A method for preparing a compressible, resilient, homogenous composite sheet having sufficiently low modulus of compression to provide a cushioning effect, said method comprising (A) forming an aqueous dispersion of fibers, (B) forming an aqueous dispersion of particles of hydrophilic polyurethane foam prepared by dispersing a prepolymer of a hydrophilic oxyalkylene polyol capped with an isocyanate in water and allowing the isocyanate groups to react essentially simultaneously with the water to form polyurethane particles in-situ, wherein said prepolymer is from about 10 to about 60% by weight, based on total weight of prepolymer and fibers, wherein said polyol has a molecular weight from about 200 to about 20,000 and contains at least 50 mole percent oxyethylene units, wherein the size of the polyurethane particles are not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water is used for every part of prepolymer, (C) mixing dispersion (A) and (B), (D) wet-layering the mixed dispersion onto a support, and (E) removing water from the resulting supported fiber/foam sheet.
Claim 2
Independent Claim
174 words
A method for preparing a compressible, resilient, homogenous composite sheet having sufficiently low modulus of compression to provide a cushioning effect, said method comprising (A) forming an aqueous dispersion of fibers, (B) forming an aqueous dispersion of particles of hydrophilic polyurethane foam prepared by dispersing a prepolymer of a hydrophilic oxyalkylene polyol capped with an isocyanate in water and allowing the isocyanate groups to react essentially simultaneously with the water to form polyurethane particles in-situ, wherein said prepolymer is from about 10 to about 60% by weight, based on total weight of prepolymer and fibers, wherein said polyol has a molecular weight from about 200 to about 20,000 and contains at least 50 mole percent oxyethylene units, wherein the size of the polyurethane particles are not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water is used for every part of prepolymer, (C) mixing dispersion (A) and (B), (D) wet-layering the mixed dispersion onto a support, and (E) removing water from the resulting supported fiber/foam sheet.
Claim 3
Dependent Claim
11 words
A method as in claim 1 wherein the fibers are asbestos.
Claim 4
Dependent Claim
11 words
A method as in claim 1 wherein cellulosic fibers are employed.
Claim 5
Dependent Claim
17 words
A method as in claim 1 wherein latex is added to the mixed dispersions before wet layering.
Claim 6
Dependent Claim
23 words
A method as in claim 1 wherein the hydrophilic oxyalkylene polyol contain at least 60 mole percent of oxyethylene units in the backbone.
Claim 7
Dependent Claim
25 words
A method as in claim 1 wherein from about 7 to about 50 parts of water is used for every part of isocyanate capped prepolymer.
Claim 8
Independent Claim
175 words
A method for preparing a compressible resilient, homogeneous compsite sheet having sufficiently low modulus of compression to provide a cushioning effect, said method comprising: (A) forming an aqueous dispersion of fibers and particles of hydrophilic polyurethane foam by dispersing into an aqueous fiber dispersion a hydrophilic oxyalkylene polyol capped with an isocyanate whereby said capped polyol reacts essentially simultaneously with the water in said fiber dispersion to form particulate polyurethane foam particles in-situ to produce a fiber/foam dispersion, wherein said capped polyol is from about 10 to about 60% by weight based on total weight of capped polyol and fiber, wherein said polyol has a molecular weight from about 200 to about 20,000, wherein said polyol contains at least about 50 mole percent oxyethylene units, wherein the foam particles size is not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water for every part of capped polyol is employed. (B) wet-layering said fiber/foam dispersion onto a support, and (C) removing water from the resulting supported fiber/foam sheet.
Claim 9
Independent Claim
175 words
A method for preparing a compressible resilient, homogeneous compsite sheet having sufficiently low modulus of compression to provide a cushioning effect, said method comprising: (A) forming an aqueous dispersion of fibers and particles of hydrophilic polyurethane foam by dispersing into an aqueous fiber dispersion a hydrophilic oxyalkylene polyol capped with an isocyanate whereby said capped polyol reacts essentially simultaneously with the water in said fiber dispersion to form particulate polyurethane foam particles in-situ to produce a fiber/foam dispersion, wherein said capped polyol is from about 10 to about 60% by weight based on total weight of capped polyol and fiber, wherein said polyol has a molecular weight from about 200 to about 20,000, wherein said polyol contains at least about 50 mole percent oxyethylene units, wherein the foam particles size is not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water for every part of capped polyol is employed. (B) wet-layering said fiber/foam dispersion onto a support, and (C) removing water from the resulting supported fiber/foam sheet.
Claim 10
Dependent Claim
11 words
A method as in claim 7 wherein the fibers are asbestos.
Claim 11
Dependent Claim
11 words
A method as in claim 7 wherein cellulosic fibers are employed.
Claim 12
Dependent Claim
16 words
A method as in claim 7 wherein latex is added to the dispersion before wet layering.
Claim 13
Dependent Claim
23 words
A method as in claim 7 wherein the hydrophilic oxyalkylene polyol contains at least 60 mole percent of oxyalkylene units in the backbone.
Claim 14
Dependent Claim
29 words
A method as in claim 7 wherein at least 7 parts of water is used for each part by weight of the combined weight of capped polyol and fiber.
Claim 15
Dependent Claim
164 words
In the method for preparing a compressible resilient, homogenous composite sheet by forming an aqueous dispersion containing particulate foam and fibers, wet-layering the fiber/foam dispersion onto a support to form a sheet, and removing water from the resulting supported sheet, the improvement comprising using, in place of shredded foam particles, a particulate dispersion of polyurethane foam prepared by dispersing an isocyanate-capped hydrophilic polyoxyalkylene polyol in water and allowing the isocyanate groups to react essentially simultaneously in-situ with the water to provide the foam particles, wherein said capped polyol is from about 10 to about 60% by weight based on total weight of capped polyol and fibers, wherein said hydrophilic polyoxyalkylene polyol has a molecular weight from about 200 to about 20,00 and contains at least 50 mole percent oxyethylene units, wherein the size of said foam particles is not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water is used for every part of capped polyol.
Claim 16
Dependent Claim
164 words
In the method for preparing a compressible resilient, homogenous composite sheet by forming an aqueous dispersion containing particulate foam and fibers, wet-layering the fiber/foam dispersion onto a support to form a sheet, and removing water from the resulting supported sheet, the improvement comprising using, in place of shredded foam particles, a particulate dispersion of polyurethane foam prepared by dispersing an isocyanate-capped hydrophilic polyoxyalkylene polyol in water and allowing the isocyanate groups to react essentially simultaneously in-situ with the water to provide the foam particles, wherein said capped polyol is from about 10 to about 60% by weight based on total weight of capped polyol and fibers, wherein said hydrophilic polyoxyalkylene polyol has a molecular weight from about 200 to about 20,00 and contains at least 50 mole percent oxyethylene units, wherein the size of said foam particles is not less than about 0.01 inch mesh, and wherein from about 7 to about 50 parts of water is used for every part of capped polyol.
Claim 17
Dependent Claim
27 words
A method as in claim 13 wherein a separate fiber dispersion and a separate particulate foam dispersion are formed and subsequently combined to form the fiber/foam dispersion.
Claim 18
Dependent Claim
11 words
A method as in claim 14 wherein the fibers are asbestos.
Claim 19
Dependent Claim
11 words
The method as in claim 14 wherein cellulosic fibers are employed.
Claim 20
Dependent Claim
16 words
A method as in claim 16 wherein latex is added to the dispersion of cellulosic fibers.
Claim 21
Dependent Claim
23 words
A method as in claim 14 wherein the hydrophilic oxyalkylene polyol contains at least 60 mole percent of oxyethylene units in the backbone.
Claim 22
Dependent Claim
24 words
A method as in claim 13 wherein the hydrophilic isocyanate-capped prepolymer is dispersed in an aqueous dispersion of fibers to form the fiber/foam dispersion.
Claim 23
Dependent Claim
11 words
A method as in claim 19 wherein the fibers are asbestos.
Claim 24
Dependent Claim
11 words
A method as in claim 19 wherein cellulosic fibers are employed.
Claim 25
Dependent Claim
16 words
A method as in claim 19 wherein latex is added to the fiber/foam dispersion before wet-layering.
Claim 26
Dependent Claim
23 words
A method as in claim 19 wherein the hydrophilic oxyalkylene polyol contains at least 60 mole percent of oxyethylene units in the backbone.
Claim 27
Dependent Claim
60 words
A compressible, resilient, homogenous composite sheet comprising in combination, particles of hydrophilic polyoxyalkylene polyurethane foam and fibers interwined therewith and binding the particles together to form said sheet, the improvement wherein said foam particles are formed by in-situ foaming by dispersing an isocyanate capped hydrophilic oxyalkylene polyol in an aqueous dispersion of fibers, according to the method of claim 12.
Claim 28
Dependent Claim
11 words
A sheet as in claim 24 wherein the fibers are asbestos.
Claim 29
Dependent Claim
11 words
A sheet as in claim 24 wherein cellulosic fibers are employed.
Claim 30
Dependent Claim
15 words
A sheet as in claim 24 wherein latex is employed in combination with the fibers.
Claim 31
Dependent Claim
22 words
A sheet as in claim 24 wherein the oxyalkylene polyurethane contains at least 50 mole percent of oxyethylene units in the backbone.
Claim 32
Dependent Claim
67 words
A composite laminate comprising in combination, particles of hydrophilic polyoxyalkylene polyurethane foam and fibers intertwined therewith and binding the particles together to form a sheet, and a porous web supporting and adhering to said sheet, the improvement wherein said foam particles are formed by in-situ foaming by dispersing an isocyanate capped hydrophilic oxyalkylene polyol in an aqueous dispersion of fibers according to the method of claim 12.
Claim 33
Dependent Claim
13 words
A laminate as in claim 29 wherein the web is a woven fabric.
Claim 34
Dependent Claim
13 words
A laminate as in claim 29 wherein the web is a non-woven material.
Claim 35
Dependent Claim
11 words
A laminate as in claim 29 wherein the fibers are asbestos.
Claim 36
Dependent Claim
11 words
A laminate as in claim 29 wherein the fibers are cellulose.
Claim 37
Dependent Claim
15 words
A laminate as in claim 29 wherein latex is employed in combination with the fibers.
Claim 38
Dependent Claim
23 words
A laminate as in claim 29 wherein the polyurethane foam particles contain at least 60 mole percent oxyethylene units in the polyoxyalkylene backbone.
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) | 1983-01-07 | 1983-07-09 | 1984-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-07 | 1987-07-09 | 1988-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-07 | 1991-07-09 | 1992-01-08 | $7700.00 | Window Closed / Lapsed |