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US3989712A Expired / Lapsed US ⏱️ 0.0 years remaining

Thio-bis(phthalimides)

Assignee: General Electric Co
•
Filing: 1973-03-30
•
Granted: 1976-11-02
•
Expires: 1993-03-30
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Abstract

Abstract A method is provided for making bis(thioetherphthalic anhydride)s from bis(thioetherphthalimide)s. The latter compounds can be made by using an alkali metal sulfide with an N-substituted phthalimide having an alkali metal sulfide displaceable radical attached to the ring.

Inventors

  • 👤 Frank J. Williams, III

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 11:36
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/77; C07D307/87; C07D307/89; C07D209/00; C07D209/02; C07D209/04; C07D209/30; C07D209/32; C07D209/38; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/423

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 1 words
3,3'-bis(N-phenylphthalimide)sulfide.
Claim 2
Dependent Claim 1 words
3,3'-bis(N-phenylphthalimide)sulfide.
Claim 3
Dependent Claim 1 words
4,4'-bis(N-phenylphthalimide)sulfide.
Claim 4
Dependent Claim 1 words
4,4'-bis(N-phenylphthalimide)sulfide.
Claim 5
Dependent Claim 1 words
3,3'bis(N-butylphthalimide)sulfide.
Claim 6
Dependent Claim 1 words
3,3'bis(N-butylphthalimide)sulfide.

References Cited (Backward Citations)

US3374274A Cited
US3422064A Cited
US3692740A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-11-02 1980-05-03 1980-11-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-11-02 1984-05-03 1984-11-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-11-02 1988-05-03 1988-11-02 $7700.00 Window Closed / Lapsed

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