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US2505818A Expired / Lapsed US ⏱️ 0.0 years remaining

Solubilizing tanning bark extracts with waste sulfite liquors

Assignee: United States Department of Agriculture
•
Filing: 1946-07-23
•
Granted: 1950-05-02
•
Expires: 1966-07-23
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Abstract

No abstract record available.

Inventors

  • 👤 Kenneth T Williams
  • 👤 Earl F Potter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 01:33
CPC Classifications
C; C08; C08H; C08H6/00

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 113 words
A METHOD OF SOLUBILIZING THE INSOLUBLE MATERIAL CONTAINED IN AN AQUEOUS EXTRACT OF WESTERN HEMLOCK BARK, COMPRISING MIXING THE AQUEOUS EXTRACT WITH A SULFITE LIQUOR PRODUCED DURING THE COOKING OF WOOD IN THE MANUFACTURE OF WOOD PULP AND MODIFIED SOLELY BY HAVING HAD ITS PH RAISED TO APPROXIMATELY 5 AND ITS ALKALINE EARTH METAL IONS SUBSTANTIALLY REPLACED BY SODIUM IONS, SAID EXTRACT AND SAID LIQUOR BEING MIXED IN SUCH PROPORTIONS THAT ABOUT THREE-FOURTHS OF THE TOTAL DISSOLVED MATERIAL PRESENT IN THE MIXTURE IS DERIVED FROM THE EXTRACT AND THE REMAINDER OF TOTAL DISSOLVED MATERIAL IS DERIVED FROM THE LIQUOR, AND HEATING THIS MIXTURE AT A TEMPERATURE OF ABOUT 180*F. FOR ABOUT THREE HOURS.

References Cited (Backward Citations)

US909343A Cited
US1063428A Cited
US940394A Cited
US1147245A Cited
US1327105A Cited
US1563010A Cited
US2244410A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1953-05-01 1953-10-31 1954-05-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1957-05-01 1957-10-31 1958-05-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1961-05-01 1961-10-31 1962-05-02 $7700.00 Window Closed / Lapsed

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