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US2941919A Expired / Lapsed US ⏱️ 0.0 years remaining

Sizing of paper

Assignee: Hercules Powder Co
•
Filing: 1957-01-31
•
Granted: 1960-06-21
•
Expires: 1977-01-31
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Abstract

No abstract record available.

Inventors

  • 👤 Spencer H Watkins

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 15:25
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/62

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 113 words
THE PROCESS OF SIZING PAPER WHICH COMPRISES ADDING TO AN AQUEOUS SUSPENSION OF PAPER PULP AN AQUEOUS AND AT LEAST PARTIALLY NEUTRALIZED DISPERSION OF TALL OIL ROSIN, IN AN AMOUNT SUCH AS TO SUPPLY FROM ABOUT 1/4 TO ABOUT 4% OF THE ROSIN, BASED ON THE WEIGHT TO DRY PULP, IN SAID SUSPENSION, SAID TALL OIL ROSIN HAVING BEEN SUBJECTED TO TREATMENT WITH FROM ABOUT 1% TO ABOUT 4%, BASED ON THE WEIGHT OF TALL OIL ROSIN OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND FORMALDEHYDE-YIELDING MATERIALS, AT A TEMPERATURE OF FROM ABOUT 100*C. TO ABOUT 200*C. IN THE PRESENCE OF AN ACID CATALYST PRIOR TO SAPONIFICATION WITH AQUEOUS ALKALI.
Claim 2
Dependent Claim 113 words
THE PROCESS OF SIZING PAPER WHICH COMPRISES ADDING TO AN AQUEOUS SUSPENSION OF PAPER PULP AN AQUEOUS AND AT LEAST PARTIALLY NEUTRALIZED DISPERSION OF TALL OIL ROSIN, IN AN AMOUNT SUCH AS TO SUPPLY FROM ABOUT 1/4 TO ABOUT 4% OF THE ROSIN, BASED ON THE WEIGHT TO DRY PULP, IN SAID SUSPENSION, SAID TALL OIL ROSIN HAVING BEEN SUBJECTED TO TREATMENT WITH FROM ABOUT 1% TO ABOUT 4%, BASED ON THE WEIGHT OF TALL OIL ROSIN OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND FORMALDEHYDE-YIELDING MATERIALS, AT A TEMPERATURE OF FROM ABOUT 100*C. TO ABOUT 200*C. IN THE PRESENCE OF AN ACID CATALYST PRIOR TO SAPONIFICATION WITH AQUEOUS ALKALI.

References Cited (Backward Citations)

US2084213A Cited
US2197383A Cited
US2684300A Cited
US2712994A Cited
US2720514A Cited
US2744889A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1963-06-21 1963-12-21 1964-06-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1967-06-21 1967-12-21 1968-06-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1971-06-21 1971-12-21 1972-06-21 $7700.00 Window Closed / Lapsed

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