Patent US4218528A successfully refreshed from Google Patents.
US4218528A
Expired / Lapsed
US
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Electrophotographic photoreceptor with phthalocyanine in phenol resin binder
Assignee: Konica Minolta Inc
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Filing: 1978-06-08
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Granted: 1980-08-19
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Expires: 1998-06-08
Abstract
Abstract The method for forming an electrostatic image according to the present invention comprises the steps of charging an electrophotographic photoreceptor, which is subjected to dark decay after the charging step, and effecting an exposure by activation light and an imagewise exposure on the electrophotographic photoreceptor. The exposure by activation light is effected prior to the imagewise exposure and in a step including at least a portion of the charging step or dark decay. This causes a remarkable sensitization effect in the electrophotographic photoreceptor, suitably adapted for use in an electrophotographic copying machine of a repeated transfer type.
Inventors
- 👤 Fumio Shimada
- 👤 Masatoshi Matsuzaki
- 👤 Masafumi Uehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:50
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0557; G03G5/0567; G03G13/00; G03G13/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
140 words
An electrophotographic photoreceptor consisting essentially of a resin and a photoconductive phthalocyanine pigment dispersed in said resin in a ratio by weight of said pigment to said resin of 1:3 to 1:20, adapted for use in forming an electrostatic image in an electrophotography, wherein said resin comprises a phenol resin having a polymerization degree of from 2 to 10,000 consisting essentially of a substance having the following formula ##STR10## where R and R 1 are a hydrogen atom or methyl radical; R 2 a hydrogen atom or epoxy radical; and R 3 , R 4 and R 5 are a hydrogen atom, halogen atom or alkyl or alkoxy radical having 1 to 20 carbon atoms, at least one of said R 3 , R 4 and R 5 being an alkyl or alkoxy radical having 4 to 20 carbon atoms.
Claim 2
Dependent Claim
140 words
An electrophotographic photoreceptor consisting essentially of a resin and a photoconductive phthalocyanine pigment dispersed in said resin in a ratio by weight of said pigment to said resin of 1:3 to 1:20, adapted for use in forming an electrostatic image in an electrophotography, wherein said resin comprises a phenol resin having a polymerization degree of from 2 to 10,000 consisting essentially of a substance having the following formula ##STR10## where R and R 1 are a hydrogen atom or methyl radical; R 2 a hydrogen atom or epoxy radical; and R 3 , R 4 and R 5 are a hydrogen atom, halogen atom or alkyl or alkoxy radical having 1 to 20 carbon atoms, at least one of said R 3 , R 4 and R 5 being an alkyl or alkoxy radical having 4 to 20 carbon atoms.
Claim 3
Dependent Claim
20 words
An electrophotographic photoreceptor according to claim 1 wherein the degree of polymerization of said resin is from 2 to 100.
Claim 4
Dependent Claim
24 words
An electrophotographic photoreceptor according to claim 1, wherein said photoconductive phthalocyanine pigment contains metalfree phthalocyanine, copper phthalocyanine, cobalt phthalocyanine, lead phthalocyanine or zinc phthalocyanine.
Claim 5
Dependent Claim
24 words
An electrophotographic photoreceptor according to claim 3, wherein said metalfree phthalocyanine and copper phthalocyanine are of an α, β, γ, χ, π or ε-type.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-19 | 1984-02-18 | 1984-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-19 | 1988-02-18 | 1988-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-19 | 1992-02-18 | 1992-08-19 | $7700.00 | Window Closed / Lapsed |