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US3068141A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of refining kraft wood pulp

Assignee: Eastman Kodak Co
•
Filing: 1959-09-10
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Granted: 1962-12-11
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Expires: 1979-09-10
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Abstract

No abstract record available.

Inventors

  • 👤 Robert H Macclaren
  • 👤 Frank L Wells

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 04:48
CPC Classifications
D; D21; D21C; D21C9/00; D21C9/08; D21C9/083

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 80 words
A METHOD OF PREPARING REFINED KRAFT WOOD PULP USEFUL AS A STARTING MATERIAL IN THE PREPARATION OF CELLULOSE ESTER PRODUCTS WHICH COMPRISES SUBJECTING KRAFT PULP TO A SERIES OF TREATMENTS AT LEAST TWO OF THE STEPS OF WHICH INVOLVES, (1) TREATING THE PULP WITH AQUEOUS CARUSTIC ALKALI OF 1/2-2% CONCENTRATION AT 100-140*C., AND (2) TREATING WITH AQUEOUS CAUSTIC ALKALI OF 8-12% CONCENTRATION CONTAINING 2-5% OF A BORON COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM META-BORATE, BORAX AND BORIC ACID.
Claim 2
Independent Claim 80 words
A METHOD OF PREPARING REFINED KRAFT WOOD PULP USEFUL AS A STARTING MATERIAL IN THE PREPARATION OF CELLULOSE ESTER PRODUCTS WHICH COMPRISES SUBJECTING KRAFT PULP TO A SERIES OF TREATMENTS AT LEAST TWO OF THE STEPS OF WHICH INVOLVES, (1) TREATING THE PULP WITH AQUEOUS CARUSTIC ALKALI OF 1/2-2% CONCENTRATION AT 100-140*C., AND (2) TREATING WITH AQUEOUS CAUSTIC ALKALI OF 8-12% CONCENTRATION CONTAINING 2-5% OF A BORON COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM META-BORATE, BORAX AND BORIC ACID.

References Cited (Backward Citations)

US1868570A Cited
US1935580A Cited
US2898333A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1965-12-10 1966-06-11 1966-12-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1969-12-10 1970-06-11 1970-12-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1973-12-10 1974-06-11 1974-12-11 $7700.00 Window Closed / Lapsed

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