Patent US3068141A successfully refreshed from Google Patents.
US3068141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of refining kraft wood pulp
Assignee: Eastman Kodak Co
•
Filing: 1959-09-10
•
Granted: 1962-12-11
•
Expires: 1979-09-10
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 07:09
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)
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 |