Patent US3723392A successfully refreshed from Google Patents.
US3723392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethanes based on 2,3-dibromo-but-2-ene-1,4-diol
Assignee: Bayer AG
•
Filing: 1972-01-17
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Granted: 1973-03-27
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Expires: 1992-01-17
Abstract
Abstract Noncellular polyurethane plastics are prepared from organic compounds having hydroxyl groups and a molecular weight from about 800 to about 3,000, organic diisocyanates and 2,3dibromobut-2-ene-1,4-diol. The polyurethane elastomers due to their improved chemical and thermal stability are eminently suitable in the production of molded articles.
Inventors
- 👤 K Konig
- 👤 E Muller
- 👤 K Wagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:50
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/67; C08G18/675; C08G18/677; C08G18/6775
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
11 words
The polyurethane elastomer of claim 1 wherein R'' is 100 percent
Claim 2
Dependent Claim
10 words
The polyurethane elastomer of claim 1 wherein R'' is a
References Cited (Backward Citations)
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Cited
US2753319A
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US2729618A
Cited
US3100759A
Cited
US3219634A
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US3676380A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |