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US2533178A Expired / Lapsed US ⏱️ 0.0 years remaining

alpha-(phthalimidomethyl-anilino)-anthraquinones and process of preparing the same

Assignee: GAF Chemicals Corp
•
Filing: 1948-05-01
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Granted: 1950-12-05
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Expires: 1968-05-01
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Abstract

No abstract record available.

Inventors

  • 👤 David I Randall
  • 👤 Jr Edgar E Renfrew

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 14:52
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/16; C09B1/20; C09B1/26; C09B1/32

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 8 words
AN ANTHRAQUINONE DYESTUFF CHARACTERIZED BY THE FOLLOWING FORMULA:

References Cited (Backward Citations)

US1917801A Cited
US2245780A Cited
US2340528A Cited
US2335680A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1953-12-04 1954-06-05 1954-12-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1957-12-04 1958-06-05 1958-12-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1961-12-04 1962-06-05 1962-12-05 $7700.00 Window Closed / Lapsed

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