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US2423767A Expired / Lapsed US ⏱️ 0.0 years remaining

Tone-control agents for silver halide emulsions

Assignee: Ilford Imaging UK Ltd
•
Filing: 1944-12-13
•
Granted: 1947-07-08
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Expires: 1964-12-13
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Abstract

No abstract record available.

Inventors

  • 👤 Fry Douglas James
  • 👤 Brooks James Douglas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 05:15
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/35; G03C5/00; G03C5/26; G03C5/29; G03C5/305; Y; Y10; Y10S; Y10S430/00; Y10S430/162; Y10S430/166

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US394290A Cited
US1623499A Cited
US2124159A Cited
US2266442A Cited
US2286662A Cited
US2276254A Cited
US2309492A Cited
US2298093A Cited
US2346065A Cited
US2311098A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1950-07-07 1951-01-06 1951-07-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1954-07-07 1955-01-06 1955-07-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1958-07-07 1959-01-06 1959-07-08 $7700.00 Window Closed / Lapsed

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