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US2797232A Expired / Lapsed US ⏱️ 0.0 years remaining

Hidden polyisocyanates

Assignee: Bayer AG
•
Filing: 1954-03-31
•
Granted: 1957-06-25
•
Expires: 1974-03-31
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Abstract

No abstract record available.

Inventors

  • 👤 Bunge Wilhelm

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 10:19
CPC Classifications
C; C07; C07C; C07C271/00; C08; C08L; C08L75/00; C08L75/04

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 86 words
PROCESS FOR THE CONVERSION OF POLYISOCYANATES AND DICARBOXYLIC ACIDS INTO URETHANES CAPABLE OF BEING THERMALLY DECOMPOSED INTO POLYISOCYANATES HAVING A HIGHER MOLECULAR WEIGHT THAN THE STARTING MATERIAL, WHICH COMPRISES CONTACTING A HYDROXY-ALKYL-CARBAMIC ACID-ARYL ESTER WITH A MEMBER SELECTED FROM THE GROUP CONSISTING OF ORGANIC DIISOCYANATES, ORGANIC TRIISOCYANATES, DICARBOXYLIC ACIDS, AND FUNCTIONAL DERIVATIVES OF DICARBOXYLIC ACIDS AT A TEMPERATURE BELOW ABOUT 150*C., AND RECOVERING THE URETHANE FORMED, WHICH IS CAPABLE OF YIELDING AT INCREASED TEMPERATURES A FREE POLYISOCYANATE HAVING A HIGHER MOLECULAR WEIGHT THAN SAID GROUP MEMBER.
Claim 2
Dependent Claim 86 words
PROCESS FOR THE CONVERSION OF POLYISOCYANATES AND DICARBOXYLIC ACIDS INTO URETHANES CAPABLE OF BEING THERMALLY DECOMPOSED INTO POLYISOCYANATES HAVING A HIGHER MOLECULAR WEIGHT THAN THE STARTING MATERIAL, WHICH COMPRISES CONTACTING A HYDROXY-ALKYL-CARBAMIC ACID-ARYL ESTER WITH A MEMBER SELECTED FROM THE GROUP CONSISTING OF ORGANIC DIISOCYANATES, ORGANIC TRIISOCYANATES, DICARBOXYLIC ACIDS, AND FUNCTIONAL DERIVATIVES OF DICARBOXYLIC ACIDS AT A TEMPERATURE BELOW ABOUT 150*C., AND RECOVERING THE URETHANE FORMED, WHICH IS CAPABLE OF YIELDING AT INCREASED TEMPERATURES A FREE POLYISOCYANATE HAVING A HIGHER MOLECULAR WEIGHT THAN SAID GROUP MEMBER.

References Cited (Backward Citations)

BE506813A Cited
GB620116A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1960-06-24 1960-12-24 1961-06-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1964-06-24 1964-12-24 1965-06-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1968-06-24 1968-12-24 1969-06-25 $7700.00 Window Closed / Lapsed

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