US3933548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of urethane foams and laminates thereof
Assignee: POLYVINYL/PERMUTHAN Co A CORP OF
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Filing: 1974-08-19
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Granted: 1976-01-20
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Expires: 1994-08-19
Abstract
Abstract Thin flexible urethane foam film layers are produced by spreading a layer of polyurethane reactants over a carrier sheet at a uniform layer thickness. The polyurethane reactants consist essentially of an isocyanate and a hydroxyl terminated polyol having an inorganic carbon dioxide producing blowing agent incorporated therein and being free of water. The unconfined film layer is then heated to a temperature in the range of from 260°F to 390°F to cause gellation and release of the carbon dioxide in the mixture with final formation of a uniform thickness flexible polyurethane foam product.
Inventors
- 👤 Harry M. Anderson, Jr.
- 👤 Charles K. Knisely
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:32
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/06; C08J9/08; B; B32; B32B; B32B5/00; B32B5/18; B32B5/20; B32B38/00; B32B2038/0052; B32B2038/0084; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0278; B32B2307/00; B32B2307/50; B32B2307/536; C08J2201/00; C08J2201/02; C08J2201/022; C08J2203/00; C08J2203/02; C08J2375/00; C08J2375/04; Y; Y10; Y10S; Y10S264/00; Y10S264/05; Y10S428/00; Y10S428/904; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
102 words
A method of forming a flexible polyurethane foam layer having uniform controlled film layer thickness, said method comprising, spreading a layer of a polyurethane reactants containing mixture over a carrier surface in a uniform layer thickness, said polyurethane reactants consisting essentially of an isocyanate and a hydroxyl terminated polyol having from 1 to 9% by weight thereof of an inorganic carbon dioxide producing blowing agent incorporated therein, and heating said layer to a temperature in the range of from 260°F to 390°F to cause release of carbon dioxide in said mixture and formation of polyurethane foam in a uniform thickness final product.
Claim 2
Independent Claim
102 words
A method of forming a flexible polyurethane foam layer having uniform controlled film layer thickness, said method comprising, spreading a layer of a polyurethane reactants containing mixture over a carrier surface in a uniform layer thickness, said polyurethane reactants consisting essentially of an isocyanate and a hydroxyl terminated polyol having from 1 to 9% by weight thereof of an inorganic carbon dioxide producing blowing agent incorporated therein, and heating said layer to a temperature in the range of from 260°F to 390°F to cause release of carbon dioxide in said mixture and formation of polyurethane foam in a uniform thickness final product.
Claim 3
Dependent Claim
32 words
A method in accordance with the method of claim 1 wherein said inorganic blowing agent is sodium bicarbonate and said foam thickness is in the range of from 0.006 to 0.l40 inch.
Claim 4
Dependent Claim
36 words
A method in accordance with claim 2 wherein said film of urethane reactants is continuously spread over a continuously moving carrier sheet and said heating is carried out in an oven through which said sheet passes.
Claim 5
Dependent Claim
41 words
A method in accordance with the method of claim 3 wherein said oven acts to bring said mixture to a gel state while causing evolution of carbon dioxide to foam said gel, and thereafter curing said foam at a uniform thickness.
Claim 6
Dependent Claim
45 words
A method in accordance with the method of claim 4 and further comprising continuously passing a supporting layer web into contact with a surface of said gelled layer while it is tacky to form a laminate therewith prior to final cure of said polyurethane foam.
Claim 7
Dependent Claim
23 words
A method in accordance with the method of claim 1 wherein said urethane reactants are spread over a surfacing web and adhered thereto.
Claim 8
Dependent Claim
58 words
A method in accordance with the method of claim 6 and further comprising heating said foam layer to a gelled state while causing evolution of carbon dioxide, passing a supporting layer web into contact with a surface of said gelled foam layer to form a laminate therewith, and heating to cure said polyurethane foam in a composite laminate.
Claim 9
Dependent Claim
25 words
A method in accordance with the method of claim 7 wherein said foam layer thickness is in the range of from 0.010 to 0.025 inch.
Claim 10
Dependent Claim
107 words
In a method of forming polyurethane foam layers having hardness values of 50 Shore A to 80 Shore A from polyurethane reactants containing mixtures comprising an isocyanate and a polyol, the improvement comprising, incorporating in the reactants from 1 to 9% by weight of powdered sodium bicarbonate nonreactive with the isocyanate and capable of releasing carbon dioxide at temperatures in the range of from 260°F to 390°F, positioning a film of from 0.003 inch to 0.07 inch of said mixture on a carrier layer in a uniform thickness, and heating said film to form a urethane foam having a uniform thickness of from 0.006 to 0.140 inch.
Claim 11
Dependent Claim
107 words
In a method of forming polyurethane foam layers having hardness values of 50 Shore A to 80 Shore A from polyurethane reactants containing mixtures comprising an isocyanate and a polyol, the improvement comprising, incorporating in the reactants from 1 to 9% by weight of powdered sodium bicarbonate nonreactive with the isocyanate and capable of releasing carbon dioxide at temperatures in the range of from 260°F to 390°F, positioning a film of from 0.003 inch to 0.07 inch of said mixture on a carrier layer in a uniform thickness, and heating said film to form a urethane foam having a uniform thickness of from 0.006 to 0.140 inch.
Claim 12
Dependent Claim
32 words
A method in accordance with the improvement of claim 9 wherein said polyurethane reactants comprise a first component containing an isocyanate and a second component containing a polyol and said sodium bicarbonate.
Claim 13
Dependent Claim
47 words
A method in accordance with the method of claim 10 and further comprising said isocyanate containing component further comprising benzoyl chloride in an amount to inhibit a polyurethane reaction and give a pot life of the two components when mixed of at least 3 hours at 72°F.
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) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |