Patent US2761884A successfully refreshed from Google Patents.
US2761884A
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Preparation of ditolyl methane
Assignee: Stamicarbon BV
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Filing: 1955-03-22
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Granted: 1956-09-04
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Expires: 1975-03-22
Abstract
No abstract record available.
Inventors
- 👤 Koorevaar Jan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:24
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/86; C07C2/862; C07C2/867; C07C2527/00; C07C2527/02; C07C2527/053; C07C2527/054
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
112 words
A PROCESS FOR PREPARING DITOLYL METHANE WHICH COMPRISES PASSING A SUSPENSION OF SOLID FORMALDEHYDE POLYMER IN AN EXCESS OF TOLUENE UPWARDLY THROUGH A LAYER OF SULPHURIC ACID OF 70-80% CONCENTRACTION BY WEIGHT WHEREIN WATER IS THE SOLE DILUENT AND AT A TEMPERATURE NOT EXCEEDING 50* C. WHILE MAINTAINING SAID SUSPENSION INTIMATELY DISPERSED IN THE ACID, SEPARATING EXCESS TOLUENE HAVING THE RESULTING DITOLYL METHANE DISSOLVED THEREIN FROM SAID SULPHURIC ACID AND RECOVERING THE DITOLYL METHANE FROM THE EXCESS TOLUENE THUS SEPARATED THE CONCENTRATION OF SAID ACID BEING MAINTAINED WITHIN THE DESIGNATED RANGE BY ADDING SULPHURIC ACID OF HIGHER CONCENTRATION AND REMOVING SULPHURIC ACID WHICH HAS BEEN DILUTED BY WATER FORMED IN THE REACTION.
Claim 2
Dependent Claim
112 words
A PROCESS FOR PREPARING DITOLYL METHANE WHICH COMPRISES PASSING A SUSPENSION OF SOLID FORMALDEHYDE POLYMER IN AN EXCESS OF TOLUENE UPWARDLY THROUGH A LAYER OF SULPHURIC ACID OF 70-80% CONCENTRACTION BY WEIGHT WHEREIN WATER IS THE SOLE DILUENT AND AT A TEMPERATURE NOT EXCEEDING 50* C. WHILE MAINTAINING SAID SUSPENSION INTIMATELY DISPERSED IN THE ACID, SEPARATING EXCESS TOLUENE HAVING THE RESULTING DITOLYL METHANE DISSOLVED THEREIN FROM SAID SULPHURIC ACID AND RECOVERING THE DITOLYL METHANE FROM THE EXCESS TOLUENE THUS SEPARATED THE CONCENTRATION OF SAID ACID BEING MAINTAINED WITHIN THE DESIGNATED RANGE BY ADDING SULPHURIC ACID OF HIGHER CONCENTRATION AND REMOVING SULPHURIC ACID WHICH HAS BEEN DILUTED BY WATER FORMED IN THE REACTION.
References Cited (Backward Citations)
US1907455A
Cited
GB446450A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-09-04 | 1960-03-05 | 1960-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-09-04 | 1964-03-05 | 1964-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-09-04 | 1968-03-05 | 1968-09-04 | $7700.00 | Window Closed / Lapsed |