US3975424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacture of tetrafluoroterephthalonitrile
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1975-07-07
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Granted: 1976-08-17
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Expires: 1995-07-07
Abstract
Abstract Tetrafluoroterephthalonitrile is produced by mixing tetrachloroterephthalonitrile, dry powdered potassium fluoride and a polar solvent having a water content of not more than 0.2% by weight and heating the resultant mixture with simultaneous agitation.
Inventors
- 👤 Shozo Fujii
- 👤 Kan Inukai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:20
CPC Classifications
C; C07; C07C; C07C255/00; C07C255/49; C07C255/50; C07C255/51
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
95 words
A method for the manufacture of tetrafluoroterephthalonitrile, which comprises mixing tetrachloroterephthalonitrile, from 0.2 to 1.5 moles per atom of chloride of said tetrachloroterephthalonitrile of dry powdered potassium fluoride and a polar solvent selected from the group consisting of dimethylformamide, diethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethylsulfoxide, hexamethylphosphoramide and tetramethylenesulfone having a water content of not more than 0.2% by weight, heating the resultant mixture at temperatures not exceeding the boiling point of said polar solvent but exceeding 130°C with simultaneous agitation and thereby causing formation of tetrafluoroterephthalonitrile in said mixture and separating from the mixture the formed tetrafluoroterephthalonitrile.
Claim 2
Independent Claim
95 words
A method for the manufacture of tetrafluoroterephthalonitrile, which comprises mixing tetrachloroterephthalonitrile, from 0.2 to 1.5 moles per atom of chloride of said tetrachloroterephthalonitrile of dry powdered potassium fluoride and a polar solvent selected from the group consisting of dimethylformamide, diethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethylsulfoxide, hexamethylphosphoramide and tetramethylenesulfone having a water content of not more than 0.2% by weight, heating the resultant mixture at temperatures not exceeding the boiling point of said polar solvent but exceeding 130°C with simultaneous agitation and thereby causing formation of tetrafluoroterephthalonitrile in said mixture and separating from the mixture the formed tetrafluoroterephthalonitrile.
Claim 3
Dependent Claim
30 words
The method according to claim 1, wherein the polar solvent is dimethylformamide, dimethylsulfoxide or N-methyl-2-pyrrolidone and the water content of said polar solvent is not more than 0.05% by weight.
Claim 4
Dependent Claim
16 words
The method according to claim 1, wherein the separation of tetrafluoroterephthalonitrile is effected by salting out.
References Cited (Backward Citations)
US3290353A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-17 | 1980-02-16 | 1980-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-17 | 1984-02-16 | 1984-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-17 | 1988-02-16 | 1988-08-17 | $7700.00 | Window Closed / Lapsed |