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US3079296A Expired / Lapsed US ⏱️ 0.0 years remaining

Preparation of paper having improved wet strength

Assignee: Shell USA Inc
•
Filing: 1959-12-14
•
Granted: 1963-02-26
•
Expires: 1979-12-14
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Abstract

No abstract record available.

Inventors

  • 👤 William H Houff
  • 👤 Alan C Nixon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 04:29
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/41; D21H17/44; D21H17/45

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 138 words
A PROCESS FOR PRODUCING WET STRENGTH PAPER HAVING IMPROVED PROPERTIES WHICH COMPRISES ADDING AN AQUEOUS MEDIUM CONTAINING A WATER-SOLUBLIZIED POLYMER OF ACROLEIN TO AN AQUEOUS SUSPENSION OF PAPER PULP AT THE BEATER STAGE SO AS TO FORM AN AQUEOUS MEDIUM CONTAINING 0.1% TO 5% BY WEIGHT OF THE WATER-SOLUBLIZIED POLYME BASED ON WEIGHT OF THE PAPER PULP, FORMING PAPER FROM THE RESULTING PRODUCT, AND DRYING THE FORMED PAPER, THE SAID POLYMER OF ACROLEIN BEING OBTAINED BY POLYMERIZATION THROUGH THE CARBON-TO-CARBON DOUBLE BOND OF ACROLEIN, HAVING AN INTRINSIC VISCOSITY OF AT LEAST 0.5 AND POSSESSING WHEN PREPARED AT LEAST 95% OF THE THEORETICAL ALDEHYDE FUNCTION AS DETERMINDE BY ADDITION OF HYDROXYLAMINE HYDROCHLORIDE AND TITRATING WITH KARL FISCHER REAGENT THE LIBERATED WATER, THE EXPRESSION THEORETICAL ALDEHYDE AS USED ABOVE MEANING ONE ALDEHYDE GROUP PER UNIT OF ACROLEIN IN THE POLYMER.
Claim 2
Dependent Claim 138 words
A PROCESS FOR PRODUCING WET STRENGTH PAPER HAVING IMPROVED PROPERTIES WHICH COMPRISES ADDING AN AQUEOUS MEDIUM CONTAINING A WATER-SOLUBLIZIED POLYMER OF ACROLEIN TO AN AQUEOUS SUSPENSION OF PAPER PULP AT THE BEATER STAGE SO AS TO FORM AN AQUEOUS MEDIUM CONTAINING 0.1% TO 5% BY WEIGHT OF THE WATER-SOLUBLIZIED POLYME BASED ON WEIGHT OF THE PAPER PULP, FORMING PAPER FROM THE RESULTING PRODUCT, AND DRYING THE FORMED PAPER, THE SAID POLYMER OF ACROLEIN BEING OBTAINED BY POLYMERIZATION THROUGH THE CARBON-TO-CARBON DOUBLE BOND OF ACROLEIN, HAVING AN INTRINSIC VISCOSITY OF AT LEAST 0.5 AND POSSESSING WHEN PREPARED AT LEAST 95% OF THE THEORETICAL ALDEHYDE FUNCTION AS DETERMINDE BY ADDITION OF HYDROXYLAMINE HYDROCHLORIDE AND TITRATING WITH KARL FISCHER REAGENT THE LIBERATED WATER, THE EXPRESSION THEORETICAL ALDEHYDE AS USED ABOVE MEANING ONE ALDEHYDE GROUP PER UNIT OF ACROLEIN IN THE POLYMER.

References Cited (Backward Citations)

US2657192A Cited
GB783936A Cited
US2809185A Cited
GB797459A Cited
US2822298A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1966-02-25 1966-08-27 1967-02-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1970-02-25 1970-08-27 1971-02-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1974-02-25 1974-08-27 1975-02-26 $7700.00 Window Closed / Lapsed

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