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US3137655A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical brightening

Assignee: Glanzstoff AG
•
Filing: 1961-03-21
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Granted: 1964-06-16
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Expires: 1981-03-21
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Abstract

No abstract record available.

Inventors

  • 👤 Taul Horst
  • 👤 Sommer Erwin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 21:11
CPC Classifications
C; C07; C07D; C07D235/00; C07D235/02; C07D235/04; C07D235/06; C07D235/16

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 18 words
A SYNTHETIC LINEAR POLYAMIDE TEXTILE ARTICLE CONTAINING AS AN OPTICAL BRIGHTENING AGENT THE COMPOUND OF THE FORMULA: BENZIMIDAZOL-2-YL-CH=CH-(1,4-PHENYLENE)-COOH

References Cited (Backward Citations)

US2965648A Cited
US2349979A Cited
US2345700A Cited
US2791564A Cited
US2793192A Cited
US2985661A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1967-06-16 1967-12-16 1968-06-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1971-06-16 1971-12-16 1972-06-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1975-06-16 1975-12-16 1976-06-16 $7700.00 Window Closed / Lapsed

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