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US3012991A Expired / Lapsed US ⏱️ 0.0 years remaining

Chemical reactions

Assignee: Bayer AG
•
Filing: 1957-11-13
•
Granted: 1961-12-12
•
Expires: 1977-11-13
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Abstract

No abstract record available.

Inventors

  • 👤 Schultheis Heinz
  • 👤 Kallert Wilhelm
  • 👤 Delfs Detlef

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 03:07
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/16; C08G18/166; C08G18/168; Y; Y10; Y10S; Y10S273/00; Y10S273/08

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 71 words
A METHOD FOR MAKING A URETHANE WHICH COMPRISES REACTING AN ORGANIC ISOCYANATE WITH AN ORGANIC COMPOUND HAVING AT LEAST ONE REACTIVE HYDROGEN ATOM DETERMINABLE BY THE ZEREWITINOFF METHOD WHILE IN ADMIXTURE WITH A CATALYTIC AMOUNT OF A GAMMA-PYRONE HAVING AS A SUBSTITUENT AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF LOWER ALKYL RADICALS, ARYL RADICALS, ARALKYL RADICALS, HETERO CYCLIC RADICALS CONTAINING OXYGEN, CARBOXYL GROUPS AND CARBOXYLIC ACID ESTER GROUPS.
Claim 2
Independent Claim 71 words
A METHOD FOR MAKING A URETHANE WHICH COMPRISES REACTING AN ORGANIC ISOCYANATE WITH AN ORGANIC COMPOUND HAVING AT LEAST ONE REACTIVE HYDROGEN ATOM DETERMINABLE BY THE ZEREWITINOFF METHOD WHILE IN ADMIXTURE WITH A CATALYTIC AMOUNT OF A GAMMA-PYRONE HAVING AS A SUBSTITUENT AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF LOWER ALKYL RADICALS, ARYL RADICALS, ARALKYL RADICALS, HETERO CYCLIC RADICALS CONTAINING OXYGEN, CARBOXYL GROUPS AND CARBOXYLIC ACID ESTER GROUPS.

References Cited (Backward Citations)

US2374136A Cited
US2650212A Cited
US2634244A Cited
US2622987A Cited
US2729618A Cited
US2730518A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1964-12-11 1965-06-12 1965-12-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1968-12-11 1969-06-12 1969-12-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1972-12-11 1973-06-12 1973-12-12 $7700.00 Window Closed / Lapsed

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