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US2915560A Expired / Lapsed US ⏱️ 0.0 years remaining

Formaldehyde polymers and the process of producing same

Assignee: Heyden Newport Chemical Corp
•
Filing: 1957-12-12
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Granted: 1959-12-01
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Expires: 1977-12-12
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Abstract

No abstract record available.

Inventors

  • 👤 Steinhardt David
  • 👤 David X Klein
  • 👤 Robert H Barth

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 13:40
CPC Classifications
C; C08; C08G; C08G2/00; C08G2/08

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 40 words
A LINEAR FORMALDEHYDE POLYMER HAVING A STANDARD REACITVITY OF NOT MORE THAN 2, SAID STANDARD REACTIVITY BEING A MEASURE OF THE PERCENTAGE OF SAID POLYMER THAT IS DISSOLVED IN AN AQUEOUS PH 7.8 BUFFER SOLUTION AT 25*C. IN 40 MINUTES.
Claim 2
Dependent Claim 40 words
A LINEAR FORMALDEHYDE POLYMER HAVING A STANDARD REACITVITY OF NOT MORE THAN 2, SAID STANDARD REACTIVITY BEING A MEASURE OF THE PERCENTAGE OF SAID POLYMER THAT IS DISSOLVED IN AN AQUEOUS PH 7.8 BUFFER SOLUTION AT 25*C. IN 40 MINUTES.
Claim 3
Dependent Claim 134 words
THE PROCESS OF PRODUING A SOLID FORMALDEHYDE POLYMER OF LOW REACTIVITY COMPRISING EVAPORATING TO SUBSTANTIAL DRYNESS AN AQUEOUS FORMALDEHYDE SOLUTION CONTAINING AT LEAST 35% BY WEIGHT OF FORMAKDEHYDE UNDER PRESSURE LESS THAN ATMOSPHERIC PRESSURE AND IN THE PRESENCE OF FROM 0.03 TO 3.5% OF SULFUR DIOXIDE, BASED ON THE WEIGHT OF FORMALDEHYDE, SO AS TO FORM A FIRST SOLID FORMALDEHYDE POLYMER HAVING A STANDARD REACTIVITY OF MORE THAN 2, AND THEREAFTER HEATING SAID FIRST SOLID FORMALDEHYDE POLYMER UNDER PRESSURE LESS THAN ATMOSPHERIC PRESSURE TO FORM A SECOND FORMALDEHYDE POLYMER AND CONTINUING SUCH HEATING UNTIL SAID SECOND FORMALDEHYDE POLYMER HAS A STANDARD REACTIVITY OF NOT MORE THAN 2, SAID STANDARD REACTIVITY BEING A MEASURE OF THE PERCENTAGE OF SAID POLYMER THAT IS DISSOLVED IN AN AQUEOUS PH 7.8 BUFFER SOLUTION AT 25*C. IN 40 MINUTES.
Claim 4
Dependent Claim 134 words
THE PROCESS OF PRODUING A SOLID FORMALDEHYDE POLYMER OF LOW REACTIVITY COMPRISING EVAPORATING TO SUBSTANTIAL DRYNESS AN AQUEOUS FORMALDEHYDE SOLUTION CONTAINING AT LEAST 35% BY WEIGHT OF FORMAKDEHYDE UNDER PRESSURE LESS THAN ATMOSPHERIC PRESSURE AND IN THE PRESENCE OF FROM 0.03 TO 3.5% OF SULFUR DIOXIDE, BASED ON THE WEIGHT OF FORMALDEHYDE, SO AS TO FORM A FIRST SOLID FORMALDEHYDE POLYMER HAVING A STANDARD REACTIVITY OF MORE THAN 2, AND THEREAFTER HEATING SAID FIRST SOLID FORMALDEHYDE POLYMER UNDER PRESSURE LESS THAN ATMOSPHERIC PRESSURE TO FORM A SECOND FORMALDEHYDE POLYMER AND CONTINUING SUCH HEATING UNTIL SAID SECOND FORMALDEHYDE POLYMER HAS A STANDARD REACTIVITY OF NOT MORE THAN 2, SAID STANDARD REACTIVITY BEING A MEASURE OF THE PERCENTAGE OF SAID POLYMER THAT IS DISSOLVED IN AN AQUEOUS PH 7.8 BUFFER SOLUTION AT 25*C. IN 40 MINUTES.

References Cited (Backward Citations)

US2125375A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1962-11-30 1963-06-01 1963-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1966-11-30 1967-06-01 1967-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1970-11-30 1971-06-01 1971-12-01 $7700.00 Window Closed / Lapsed

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