US3440290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing polyhydroxy-aromatic compounds rich in meta orientation
Assignee: Dow Chemical Co
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Filing: 1965-08-05
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Granted: 1969-04-22
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Expires: 1985-08-05
Abstract
No abstract record available.
Inventors
- 👤 Alexander H Widiger Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:45
CPC Classifications
C; C07; C07C; C07C41/00; C07C41/01; C07C41/16; C07C37/00; C07C37/01; C07C37/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
81 words
A METHOD FOR PREPARING A POLYHYDROXY AROMATIC PRODUCT WHICH COMPRISES REACTING A MIXTURE CONSISTING ESSENTIALLY OF A CHLOROPHENOL WITH FROM 4 TO 8 MOLES OF 20 TO 50% AQUEOUS SOLUTION OF SODIUM HYDROXIDE UNDER THE MIXTURES AUTOGENOUS PRESSURE AT A TEMPERATURE OF FROM ABOUT 250* TO 270*C. FOR BETWEEN ABOUT 1/2 TO 2 HOURS, AND SEPARATING FROM THE REACTION MIXTURE A PRODUCT RICH IN META ORIENTED DIHYDROXYBENZENE, DIHYDROXY DIPHENYL ETHERS AND TRIHYDROXY DIPHENYL, AND LOW IN HYDROXY PHENOXY PHENOXYPHENOLS, AND HIGHERS.
Claim 2
Independent Claim
81 words
A METHOD FOR PREPARING A POLYHYDROXY AROMATIC PRODUCT WHICH COMPRISES REACTING A MIXTURE CONSISTING ESSENTIALLY OF A CHLOROPHENOL WITH FROM 4 TO 8 MOLES OF 20 TO 50% AQUEOUS SOLUTION OF SODIUM HYDROXIDE UNDER THE MIXTURES AUTOGENOUS PRESSURE AT A TEMPERATURE OF FROM ABOUT 250* TO 270*C. FOR BETWEEN ABOUT 1/2 TO 2 HOURS, AND SEPARATING FROM THE REACTION MIXTURE A PRODUCT RICH IN META ORIENTED DIHYDROXYBENZENE, DIHYDROXY DIPHENYL ETHERS AND TRIHYDROXY DIPHENYL, AND LOW IN HYDROXY PHENOXY PHENOXYPHENOLS, AND HIGHERS.
References Cited (Backward Citations)
US2041592A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-21 | 1972-10-21 | 1973-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-21 | 1976-10-21 | 1977-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-21 | 1980-10-21 | 1981-04-22 | $7700.00 | Window Closed / Lapsed |