Patent US2935437A successfully refreshed from Google Patents.
US2935437A
Expired / Lapsed
US
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Method of making a pigment-filled paper
Assignee: Columbia Southern Chemical Corp
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Filing: 1953-11-20
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Granted: 1960-05-03
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Expires: 1973-11-20
Abstract
No abstract record available.
Inventors
- 👤 Louis B Taylor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:15
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/63; D21H17/70; D21H17/67; D21H17/68
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A METHOD OF PREPARING PAPER WHICH COMPRISES FORMING AN AQUEOUS PULP SLURRY FROM FIBERS OF HIGHLY RESINOUS WOOD, FINELY DIVIDED PRECIPITATED ALKALINE EARTH METAL SILICATE AND AN ALKALINE REACTING ACID SALT HAVING A HYDROGEN ATOM REPLACEABLE BY A METAL, SAID ALKALINE ACID SALT BEING LESS ALKALINE THAN THE ALKALINE EARTH METAL SILICATE AND BEING REACTIVE WITH THE ALKALINE EARTH METAL SALT TO FORM AN INSOLUBLE ALKALINE EARTH METAL SALT, MAINTAINING THE SLURRY AT AN ALKALINE PH NOT EXCEEDING 9.2, REACTING ALKALINE EARTH METAL SILICATE AND THE ALKALINE ACID SALT IN THE SLURRY AND PRODUCTING PAPER FROM THE RESULTING SLURRY.
Claim 2
Independent Claim
99 words
A METHOD OF PREPARING PAPER WHICH COMPRISES FORMING AN AQUEOUS PULP SLURRY FROM FIBERS OF HIGHLY RESINOUS WOOD, FINELY DIVIDED PRECIPITATED ALKALINE EARTH METAL SILICATE AND AN ALKALINE REACTING ACID SALT HAVING A HYDROGEN ATOM REPLACEABLE BY A METAL, SAID ALKALINE ACID SALT BEING LESS ALKALINE THAN THE ALKALINE EARTH METAL SILICATE AND BEING REACTIVE WITH THE ALKALINE EARTH METAL SALT TO FORM AN INSOLUBLE ALKALINE EARTH METAL SALT, MAINTAINING THE SLURRY AT AN ALKALINE PH NOT EXCEEDING 9.2, REACTING ALKALINE EARTH METAL SILICATE AND THE ALKALINE ACID SALT IN THE SLURRY AND PRODUCTING PAPER FROM THE RESULTING SLURRY.
References Cited (Backward Citations)
US228328A
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US1345317A
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US1443454A
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US2237374A
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US2554934A
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US2599094A
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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) | 1963-05-03 | 1963-11-02 | 1964-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-05-03 | 1967-11-02 | 1968-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-05-03 | 1971-11-02 | 1972-05-03 | $7700.00 | Window Closed / Lapsed |