Patent US3798188A successfully refreshed from Google Patents.
US3798188A
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US
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Expandable polymeric composition
Assignee: Mitsui Toatsu Chemicals Inc
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Filing: 1971-10-12
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Granted: 1974-03-19
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Expires: 1991-10-12
Abstract
Abstract A POLYMERIC COMPOSITION COMPOSED OF A POLYMERIC THERMOPLASTIC MATERIAL AND 0.01-20% BY WEIGHT OF A UREA DERIVATIVE OF THE FORMULA: R1-O-CH2-NH-CO-NH-R2 WHEREIN R1 IS HYDROGEN OR ALKYL OF 1-5 CARBON ATOMS AND R2 IS HYDROGEN OR -CH2OR1. THE UREA DERIVATIVE UNDERGOES CONDENSATION WITH THE SEPARATION OF WATER AND SIMPLE ALCOHOLS AND FUNCTIONS AS A CHEMICAL BLOWING AGENT AT AN ELEVATED TEMPERATURE WITHIN THE RANGE OF 100 TO 270* C.
Inventors
- 👤 M Takizawa
- 👤 K Miyamoto
- 👤 M Asahi
- 👤 M Nakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:34
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |