US2525594A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Deinking waste paper
Assignee: EIDP Inc
•
Filing: 1947-03-06
•
Granted: 1950-10-10
•
Expires: 1967-03-06
Abstract
No abstract record available.
Inventors
- 👤 Francis L Fennell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:30
CPC Classifications
D; D21; D21C; D21C5/00; D21C5/02; D21C5/025; D21C5/027; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/64
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A PROCESS FOR DEINKING WASTE PAPER COMPOSED OF MAGAZINE STOCK CONTAINING CLAY FILLER WHICH COMPRISES PULPING SAID PAPER IN AN AQUEOUS SODIUM PEROXIDE SOLUTION CONSISTING OF WATER, SODIUM PEROXIDE AND CAUSTIC SODA, AND CONTAINING AN AMOUNT OF SAID PEROXIDE EQUAL TO 0.25% TO ABOUT 3% OF THE DRY WEIGHT OF THE PAPER AND HAVING AN ALKALINITY EQUIVALENT TO ABOUT 2% TO 8% BY WEIGHT OF CAUSTIC SODA BASED ON THE DRY WEIGHT OF THE PAPER, TO A PULP CONSISTENCY OF ABOUT 2 TO 15%, MAINTAINING THE PULP AT A TEMPERATURE OF ABOUT 140 TO 160*F. FOR 1 TO 2 HOURS AND THEN SCREENING AND WASHING THE PULP SUFFICIENTLY TO REMOVE AT LEAST A MAJOR PORTION OF THE ALKALI PRESENT.
Claim 2
Dependent Claim
119 words
A PROCESS FOR DEINKING WASTE PAPER COMPOSED OF MAGAZINE STOCK CONTAINING CLAY FILLER WHICH COMPRISES PULPING SAID PAPER IN AN AQUEOUS SODIUM PEROXIDE SOLUTION CONSISTING OF WATER, SODIUM PEROXIDE AND CAUSTIC SODA, AND CONTAINING AN AMOUNT OF SAID PEROXIDE EQUAL TO 0.25% TO ABOUT 3% OF THE DRY WEIGHT OF THE PAPER AND HAVING AN ALKALINITY EQUIVALENT TO ABOUT 2% TO 8% BY WEIGHT OF CAUSTIC SODA BASED ON THE DRY WEIGHT OF THE PAPER, TO A PULP CONSISTENCY OF ABOUT 2 TO 15%, MAINTAINING THE PULP AT A TEMPERATURE OF ABOUT 140 TO 160*F. FOR 1 TO 2 HOURS AND THEN SCREENING AND WASHING THE PULP SUFFICIENTLY TO REMOVE AT LEAST A MAJOR PORTION OF THE ALKALI PRESENT.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-10-09 | 1954-04-10 | 1954-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-10-09 | 1958-04-10 | 1958-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-10-09 | 1962-04-10 | 1962-10-10 | $7700.00 | Window Closed / Lapsed |