← Back to Patent Explorer
US3055871A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyformal-diisocyanate condensation prepolymers

Assignee: Individual
•
Filing: 1959-01-09
•
Granted: 1962-09-25
•
Expires: 1979-01-09
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 Milton S Heffler
  • 👤 Christopher L Wilson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:50
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/56

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 107 words
A PERPOLYMER COMPRISING THE REACTION PRODUCT OF AN ALIPHATIC POLYFORMAL AND AN ORGANIC DISOCYANATE WHEREIN THE INSOCYANATE GROUPS CONSTITUTE FROM ABOUT 2,4 TO ABOUT 13.0% OF THE PREPOLYMER AND THE RATIO OF HY DROXYL GROUPS TO ISOCYANATE GROUPS IN THE REACTANTS IS FROM DETWEEN 1:1.1 TO ABOUT 1:3.3; AND POLYFORMAL HAVING ONLY TERMINAL HYDROXYL GROUPS AND A MOLECULAR WEIGHT OF FROM ABOUT 750 TO ABOUT 4500 AND BEING THE OPEN CHAIN CONDENSATION OF FORMALDEHYDE AND AN ALIPHATIC POLYHYDROXY COMPOUND HAVING A MOLECULAR WEIGHT OF FROM ABOUT 62 TO ABOUT 425, THE RATIO OF FORMALDEHYDE TO HYDROXYL GROUPS IN SAID POLYFORMAL BEING FROM ABOUT 3:4 TO ABOUT 1:1:
Claim 2
Dependent Claim 107 words
A PERPOLYMER COMPRISING THE REACTION PRODUCT OF AN ALIPHATIC POLYFORMAL AND AN ORGANIC DISOCYANATE WHEREIN THE INSOCYANATE GROUPS CONSTITUTE FROM ABOUT 2,4 TO ABOUT 13.0% OF THE PREPOLYMER AND THE RATIO OF HY DROXYL GROUPS TO ISOCYANATE GROUPS IN THE REACTANTS IS FROM DETWEEN 1:1.1 TO ABOUT 1:3.3; AND POLYFORMAL HAVING ONLY TERMINAL HYDROXYL GROUPS AND A MOLECULAR WEIGHT OF FROM ABOUT 750 TO ABOUT 4500 AND BEING THE OPEN CHAIN CONDENSATION OF FORMALDEHYDE AND AN ALIPHATIC POLYHYDROXY COMPOUND HAVING A MOLECULAR WEIGHT OF FROM ABOUT 62 TO ABOUT 425, THE RATIO OF FORMALDEHYDE TO HYDROXYL GROUPS IN SAID POLYFORMAL BEING FROM ABOUT 3:4 TO ABOUT 1:1:

References Cited (Backward Citations)

US2394910A Cited
GB773991A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1965-09-24 1966-03-26 1966-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1969-09-24 1970-03-26 1970-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1973-09-24 1974-03-26 1974-09-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag