Patent US2980858A successfully refreshed from Google Patents.
Patent US3639145A successfully refreshed from Google Patents.
US3639145A
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US
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Artificial leather and method of producing the same
Assignee: Toyo Tire Corp
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Filing: 1968-07-18
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Granted: 1972-02-01
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Expires: 1988-07-18
Abstract
Abstract A method of producing artificial leathers which comprises coating a fibrous base material with a polymeric solution containing, as the principal ingredient, a polyurethane-urea elastomer and then treating the coated fibrous base material with a nonsolvent for the polymer to coagulate the polymer. Certain critical methods for producing the polyurethane-urea elastomer, broadly described as either a ''''prepolymer'''' process or a ''''oneshot'''' process are described in the specification.
Inventors
- 👤 Kanji Fujita
- 👤 Yoshiaki Sakata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:27
CPC Classifications
D; D06; D06N; D06N3/00; D06N3/12; D06N3/14; Y; Y10; Y10S; Y10S428/00; Y10S428/904; Y10T; Y10T442/00; Y10T442/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
146 words
The method as defined in claim 1 in which there is used a polyurethane-urea elastomer obtained by forming an isocyanate-terminated prepolymer from a high molecular glycol, with an average molecular weight of from about 400 to about 5,000, selected from the group consisting of poly(alkylene ether) glycols, polyacetal glycols and polyester glycols and a molar excess of an organic diisocyanate, dissolving the prepolymer in a solvent selected from the group consisting of acetone, tetrahydrofuran, acetonitrile, N,N-dimethylformamide, tetramethyl-urea and dimethylsulfoxide and then reacting the prepolymer in solution with water, the water being present in an amount corresponding to from about 10 percent to about 30 percent of the number of equivalents of the isocyanate groups in the prepolymer, and subsequently reacting the prepolymer with a diamine selected from the group consisting of hydrazine, hydrazine hydrate, ethylenediamine, 1,2-propylenediamine, tetramethylenediamine and m-xylylenediamine in order to thereby attain chain extension.
Claim 2
Dependent Claim
128 words
The method as defined in claim 1 in which there is used a polyurethane-urea elastomer obtained by adding to a solution of a high molecular glycol, with an average molecular weight of from about 400 to about 5,000, selected from the group consisting of poly(alkylene ether) glycols, polyacetal glycols and polyester glycols, water and a low molecular glycol, the molar ratio of low molecular glycol to water being adjusted to from about 90/10 to about 70/30, in a solvent selected from the group consisting of acetone, tetrahydrofuran, acetonitrile, N,N-dimethylformamide, tetramethylurea and dimethylsulfoxide, a molar equivalent amount, said equivalent taken with reference to the total active hydrogen-containing compounds in the solution, of an organic diisocyanate, and effecting the reaction between the organic diisocyanate, and the active hydrogen containing compounds.
Claim 3
Dependent Claim
34 words
The method as defined in claim 3 in which the low molecular glycol is one selected from the group consisting of ethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol and diethylene glycol.
Claim 4
Dependent Claim
25 words
The method as defined in claim 1 in which the nonsolvent is selected from the group consisting of water, ethylene glycol, glycerol, methanol and ethanol.
Claim 5
Dependent Claim
29 words
The method as defined in claim 1 in which the fibrous base material is selected from the group consisting of woven fabrics, knitted fabrics, nonwoven fabrics and fibrous fleece.
Claim 6
Dependent Claim
37 words
The method as defined in claim 1 in which there is used a polymeric solution having incorporated therein at least one polymer selected from the group consisting of nylons, polyesters, polyvinyl chlorides, acrylonitrile polymers and copolymers thereof.
Claim 7
Dependent Claim
33 words
The method as defined in claim 1 in which a finely divided solid material selected from the group consisting of precipitated calcium carbonate and milled cellulose pulp is added to the polymeric solution.
References Cited (Backward Citations)
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Cited
US3000757A
Cited
US3067482A
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US3100721A
Cited
US3190766A
Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |