Patent US3573335A successfully refreshed from Google Patents.
US3573335A
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Modification of toluylenediisocyanates
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1968-01-12
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Granted: 1971-03-30
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Expires: 1988-01-12
Abstract
Abstract MODIFIED TOLUYLENEDIISOCYANATES, WHICH ARE USEFUL FOR THE PRODUCTION OF RIGID POLYURETHANE FOAMS ACCORDING TO ONE-SHOT METHOD, ARE PRODUCED BY HEATING TOLUYLENEDIISOCYANATES IN THE PRESENCE OF SPECIFIC ORGANO-TIN COMPOUNDS AS CATALYSTS, AND THE MODIFIED TOLUYLENEDIISOCYANATES ARE ENTIRELY STABLE AND PRECIPITATE NO INSOLUBLES AND HAVE A VISCOSITY OF 20-300 CPS. AT 25*C. AND HAVE SUCH A LOW FREEZING POINT AS BELOW 3*C.
Inventors
- 👤 Juntaro Yurimoto
- 👤 Yoshindo Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:52
CPC Classifications
C; C07; C07C; C07C263/00; C07C263/18; C07F; C07F7/00; C07F7/22; C07F7/2224; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/79; C08G2110/00; C08G2110/0025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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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) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |