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US3637536A
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Highly elastic polyurethane foams based on a quasi-prepolymer of two diisocyanates
Assignee: HANS GEORG RING
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Filing: 1970-05-28
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Granted: 1972-01-25
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Expires: 1990-05-28
Abstract
Abstract Process for the manufacture of highly elastic polyurethane foams which comprises reacting (a) a mixture comprising a polyfunctional polyether glycol having a mean molecular weight between about 3,000 and 5,500, water and catalysts with (b) a quasi-prepolymer mixture of polyether polyols enriched with at least two different organic polyisocyanates. Also included is a further process whereby the mixtures are foamed in a mold at about room temperature or slightly higher.
Inventors
- 👤 Hans-Georg Ring
- 👤 Jurgen Scheffler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:23
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7607; C08G18/08; C08G18/10; C08G18/28; C08G18/40; C08G18/48; C08G18/4833; C08G18/4837; C08G18/4841; C08G2110/00; C08G2110/0008
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
51 words
The foam of claim 1 wherein the prepolymer of b is prepared by reacting a polyoxyalkylene polyol having a molecular weight of from about 3,700 to about 4,000 and a polyether alcohol having a molecular weight of about 300 in a ratio of about 5.25 to 1 with a tolylene diisocyanate.
Claim 2
Dependent Claim
24 words
The foam of claim 1 wherein the tolylene diisocyanate used to make the prepolymer is about 65 percent 2,4- and 35 percent 2,6-tolylene diisocyanate.
References Cited (Backward Citations)
US3336242A
Cited
US3356622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |