US2890231A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alkaline extraction of chemical products from bark
Assignee: WEYERHAEUSE TIMBER Co
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Filing: 1955-09-20
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Granted: 1959-06-09
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Expires: 1975-09-20
Abstract
No abstract record available.
Inventors
- 👤 Clark C Heritage
- 👤 Lionel E Dowd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:00
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/48; C11; C11B; C11B11/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
THE PROCESS OF EXTRACTING CHEMICAL PRODUCTS FROM THE BARK OF TREES WHICH COMPRISES TREATING COMMINUTED BARK WITH AN AQUEOUS SOLUTION OF AN ALKALINE REACTING SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE, USING FROM 10-20% OF THE ALKALINE REACTING SUBSTANCE, BASED UPON THE DRY WEIGHT OF THE BARK, AT A CONSISTENCY OF THE BARK OF 10-25% AND A TEMPERATURE OF ABOUT 100* C. FOR A PERIOD OF FROM 15-180 MINUTES, SEPARATING THE PHASES TO YIELD A SOLID RESIDUE AND AN EXTRACTION SOLUTION, TREATING THE SAID EXTRACTION SOLUTION WITH AN ACID REACTING SUBSTANCE IN SUFFICIENT QUANTITY TO PRODUCE A PH OF FROM 1.5 TO 5.5 WHEREBY TO YIELD A PRECIPITATE COMPRISING PHENOLIC SUBSTANCES AND WAX-LIKE SUBSTANCES, AND SEPARATING THE PRECIPITATE FROM THE SOLUTION.
Claim 2
Dependent Claim
126 words
THE PROCESS OF EXTRACTING CHEMICAL PRODUCTS FROM THE BARK OF TREES WHICH COMPRISES TREATING COMMINUTED BARK WITH AN AQUEOUS SOLUTION OF AN ALKALINE REACTING SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE, USING FROM 10-20% OF THE ALKALINE REACTING SUBSTANCE, BASED UPON THE DRY WEIGHT OF THE BARK, AT A CONSISTENCY OF THE BARK OF 10-25% AND A TEMPERATURE OF ABOUT 100* C. FOR A PERIOD OF FROM 15-180 MINUTES, SEPARATING THE PHASES TO YIELD A SOLID RESIDUE AND AN EXTRACTION SOLUTION, TREATING THE SAID EXTRACTION SOLUTION WITH AN ACID REACTING SUBSTANCE IN SUFFICIENT QUANTITY TO PRODUCE A PH OF FROM 1.5 TO 5.5 WHEREBY TO YIELD A PRECIPITATE COMPRISING PHENOLIC SUBSTANCES AND WAX-LIKE SUBSTANCES, AND SEPARATING THE PRECIPITATE FROM THE SOLUTION.
References Cited (Backward Citations)
US2676980A
Cited
US2781336A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-06-08 | 1962-12-08 | 1963-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-08 | 1966-12-08 | 1967-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-08 | 1970-12-08 | 1971-06-09 | $7700.00 | Window Closed / Lapsed |