US3726929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of dihalophenols
Assignee: Coalite and Chemical Products Ltd
•
Filing: 1969-02-07
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Granted: 1973-04-10
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Expires: 1989-02-07
Abstract
Abstract Dihalophenols are produced by the alkaline hydrolysis of trihalobenzenes in an organic solvent. The process is effected in the presence of a hydrocarbon effective to entrain reaction water or hinder sublimation of the trihalobenzene, and/or the said solvent is a C2 - C4 glycol which is removed from the reaction mixture before the dihalophenols are liberated.
Inventors
- 👤 K Payne
- 👤 M Milnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:26
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/01; C07C37/02
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
43 words
A process according to claim 1 in which the glycol is ethylene glycol, from 3-8 mols of the glycol are used per mol of trichlorobenzene, and 4-20 parts by weight of petroleum ether are employed per 100 parts by weight of the trichlorobenzene.
References Cited (Backward Citations)
US2803670A
Cited
US2952702A
Cited
US2708209A
Cited
US2769833A
Cited
US3481991A
Cited
US3417150A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-09 | 1976-10-09 | 1977-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-09 | 1980-10-09 | 1981-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |