US3987060A
Expired / Lapsed
US
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Dicyanomethylene-indeno thiophene and derivatives
Assignee: Ricoh Co Ltd
•
Filing: 1974-09-13
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Granted: 1976-10-19
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Expires: 1994-09-13
Abstract
Abstract Electrophotographic light-sensitive materials having a photoconductive layer formed on an electroconductive support, the photoconductive layer comprising an organic photoconductive compound (monomer or polymer) and 4-dicyanomethylene-4H-indeno[1,2-b]thiophene or 8-dicyanomethylene-8H-indeno[2,1-b]thiophene or their derivatives as sensitizers, and processes for preparing such compounds from 4H-indeno[1,2-b]thiophen-4-one or 8H-indeno[2,1-b]thiophen-8-one or their derivatives and malonitrile.
Inventors
- 👤 Mitsuru Hashimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:42
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/06; G03G5/0622; G03G5/0624; G03G5/0627; G03G5/0629
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
29 words
A compound of the formula: ##SPC8## wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are hydrogen or nitro groups.
Claim 2
Dependent Claim
29 words
A compound of the formula: ##SPC8## wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are hydrogen or nitro groups.
Claim 3
Dependent Claim
1 words
6,8-Dinitro-4-dicyanomethylene-4H-indeno[1,2-b]thiophene.
Claim 4
Dependent Claim
1 words
6,8-Dinitro-4-dicyanomethylene-4H-indeno[1,2-b]thiophene.
Claim 5
Dependent Claim
1 words
2,6,8-Trinitro-4-dicyanomethylene-4H-indeno[1,2-b]thiophene.
Claim 6
Dependent Claim
1 words
2,6,8-Trinitro-4-dicyanomethylene-4H-indeno[1,2-b]thiophene.
Claim 7
Dependent Claim
1 words
2,6-Dinitro-8-dicyanomethylene-8H-indeno[2,1-b]thiophene.
Claim 8
Dependent Claim
1 words
2,6-Dinitro-8-dicyanomethylene-8H-indeno[2,1-b]thiophene.
Claim 9
Dependent Claim
1 words
2,4,6-Trinitro-8-dicyanomethylene-8H-indeno[2,1-b]thiophene.
Claim 10
Dependent Claim
1 words
2,4,6-Trinitro-8-dicyanomethylene-8H-indeno[2,1-b]thiophene.
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) | 1979-10-19 | 1980-04-19 | 1980-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-19 | 1984-04-19 | 1984-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-19 | 1988-04-19 | 1988-10-19 | $7700.00 | Window Closed / Lapsed |