US3274247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of diphenylmethane diamines
Assignee: TOULOUSAINE DE PROD CHIM TOLOC
•
Filing: 1963-06-14
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Granted: 1966-09-20
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Expires: 1983-06-14
Abstract
No abstract record available.
Inventors
- 👤 Repper Marcel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:27
CPC Classifications
C; C07; C07C; C07C211/00; C07C211/43; C07C211/44; C07C211/49; C07C211/50; C07C209/00; C07C209/68; C07C209/78
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
A PROCESS FOR THE PRODUCTION OF 4,4''-DIAMINO DIPHENYLMETHANE WHICH CONSISTS ESSENTIALLY OF REACTING FORMALDEHYDE WITH A MOLAR EXCESS OF UP TO 6 MOLES OF ANILINE PER MOLE OF FORMALDEHYDE IN THE PRESENCE OF FROM ABOUT 0.15 TO ABOUT 0.5 EQUIVALENT OF HYDROCHLORIC ACID PER MOLE OF FORMALDEHYDE.
Claim 2
Dependent Claim
47 words
A PROCESS FOR THE PRODUCTION OF 4,4''-DIAMINO DIPHENYLMETHANE WHICH CONSISTS ESSENTIALLY OF REACTING FORMALDEHYDE WITH A MOLAR EXCESS OF UP TO 6 MOLES OF ANILINE PER MOLE OF FORMALDEHYDE IN THE PRESENCE OF FROM ABOUT 0.15 TO ABOUT 0.5 EQUIVALENT OF HYDROCHLORIC ACID PER MOLE OF FORMALDEHYDE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-09-19 | 1970-03-21 | 1970-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-19 | 1974-03-21 | 1974-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-19 | 1978-03-21 | 1978-09-20 | $7700.00 | Window Closed / Lapsed |