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Patent US2845464A successfully refreshed from Google Patents.
US2845464A
Expired / Lapsed
US
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Purification of bis (hydroxyaryl)-substituted compounds
Assignee: Shell Development Co
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Filing: 1954-11-15
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Granted: 1958-07-29
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Expires: 1974-11-15
Abstract
No abstract record available.
Inventors
- 👤 Jr Daniel B Luten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:41
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/68; C07C37/70
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
54 words
THE PROCESS FOR PURIFYING CRUDE 2,2-DI(4-HYDROXYPHENYL)PROPANE CONTAINING IMPURITIES OF RESINOUS CHARACTER WHICH COMPRISES LEACHING SAID 2,2-DI(4-HYDROXYPHENYL)PROPANE WHILE IN THE SOLID STATE WITH LIQUID PARAFFINIC HYDROCARBON SOLVENT CONSISTING ESSENTIALLY OF PARAFFIN HYDROCARBONS HAVING FROM 5 TO 10 CARBON ATOMS TO THE MOLECULE AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 50*C. TO ABOUT 140*C.
Claim 2
Dependent Claim
54 words
THE PROCESS FOR PURIFYING CRUDE 2,2-DI(4-HYDROXYPHENYL)PROPANE CONTAINING IMPURITIES OF RESINOUS CHARACTER WHICH COMPRISES LEACHING SAID 2,2-DI(4-HYDROXYPHENYL)PROPANE WHILE IN THE SOLID STATE WITH LIQUID PARAFFINIC HYDROCARBON SOLVENT CONSISTING ESSENTIALLY OF PARAFFIN HYDROCARBONS HAVING FROM 5 TO 10 CARBON ATOMS TO THE MOLECULE AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 50*C. TO ABOUT 140*C.
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) | 1961-07-28 | 1962-01-27 | 1962-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-28 | 1966-01-27 | 1966-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-28 | 1970-01-27 | 1970-07-29 | $7700.00 | Window Closed / Lapsed |