US4112242A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for production of 4,4-isopropylidene-bis-2,6-dibromo/phenol
Assignee: Zaklady Chemicz
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Filing: 1977-04-25
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Granted: 1978-09-05
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Expires: 1997-04-25
Abstract
Abstract Tetrabromo bisphenol A is prepared from bisphenol A by reacting it with less than four moles of bromine in organic solvent, with or without water, and with simultaneous or subsequent treatment with alkali metal chlorate.
Inventors
- 👤 Janusz Swietoslawski
- 👤 Andrzej Silowiecki
- 👤 Aleksander Ratajczak
- 👤 Barbara Nocon
- 👤 Zofia Baniak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:02
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/62
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
51 words
A process for production of 4,4'-isopropylidene-bis-/2,6-dibromo/phenol wherein each one mole of 4,4'-isopropylidenebisphenol reacts with 2,0-2,1 moles of liquid bromine in an organic solvent or organic solvent-water solution at 30°-45° C., significant in that the degree of bromine-utilisation is increased through subsequent treatment with about 0.67 mole of an alkali metal chlorate.
Claim 2
Dependent Claim
51 words
A process for production of 4,4'-isopropylidene-bis-/2,6-dibromo/phenol wherein each one mole of 4,4'-isopropylidenebisphenol reacts with 2,0-2,1 moles of liquid bromine in an organic solvent or organic solvent-water solution at 30°-45° C., significant in that the degree of bromine-utilisation is increased through subsequent treatment with about 0.67 mole of an alkali metal chlorate.
Claim 3
Dependent Claim
19 words
A process according to claim 1 wherein the reaction is carried out in presence of a strong mineral acid.
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) | 1981-09-04 | 1982-03-06 | 1982-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-04 | 1986-03-06 | 1986-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-04 | 1990-03-06 | 1990-09-05 | $7700.00 | Window Closed / Lapsed |