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US2221131A Expired / Lapsed US ⏱️ 0.0 years remaining

Nitro-dyestuffs and process of preparing them

Assignee: GAF Chemicals Corp
•
Filing: 1937-04-30
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Granted: 1940-11-12
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Expires: 1957-04-30
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Abstract

No abstract record available.

Inventors

  • 👤 Fischer Erich
  • 👤 Gmelin Walter
  • 👤 Huss Richard
  • 👤 Krzikalla Hans
  • 👤 Pardon Heinz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 23:34
CPC Classifications
C; C09; C09B; C09B51/00; C09B43/00; C09B43/11; C09B56/00; C09B56/005

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1943-11-12 1944-05-13 1944-11-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1947-11-12 1948-05-13 1948-11-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1951-11-12 1952-05-13 1952-11-12 $7700.00 Window Closed / Lapsed

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