Patent US2915560A successfully refreshed from Google Patents.
US2915560A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formaldehyde polymers and the process of producing same
Assignee: Heyden Newport Chemical Corp
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Filing: 1957-12-12
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Granted: 1959-12-01
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Expires: 1977-12-12
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 23:25
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 |