US4880717A
Expired / Lapsed
US
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Photosensitive body for electrophotography with protective and intermediate layers
Assignee: Fuji Electric Co Ltd
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Filing: 1988-11-14
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Granted: 1989-11-14
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Expires: 2008-11-14
Abstract
Abstract The present invention provides a photosensitive body of Se-based function separation type to be used in electrophotographic equipment which employs long wavelength light for writing. Such a body exhibits outstanding abrasion resistance and heat resistance without sacrificing good electrical properties. This is accomplished by interposing an intermediate layer of As-Se alloy between the surface protective layer and the chargeable layer. The intermediate layer contains As in an increasing concentration gradient across the section of the layer from the chargeable layer to the surface protective layer. This graded As concentration causes the coefficient of thermal expansion to gradually decrease across the intermediate layer section in the direction from the chargeable layer to the surface protective layer. Thus the intermediate layer prevents the surface protective layer from thermal stress and cracking by acting as a transition buffer between the differing properties of the protective layer and chargeable layer.
Inventors
- 👤 Seizo Kitagawa
- 👤 Mitsuru Narita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:33
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/043; G03G5/0433; G03G5/08; G03G5/082; G03G5/08207
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
115 words
A photosensitive body for electrophotography, comprising in sequence: a conductive substrate; a charge transfer layer comprising selenium; a chargeable layer comprising selenium; an intermediate layer; and a surface protective layer, wherein the surface protective layer has a coefficient of thermal expansion, different than that of the chargeable layer, and the coefficient of thermal expansion of the intermediate layer changes on a gradient across the section of the intermediate layer from a value substantially equal to that of the chargeable layer at an edge of the intermediate layer adjacent the chargeable layer, to a value substantially equal to that of the surface protective layer at an edge of the intermediate layer adjacent the surface protective layer.
Claim 2
Dependent Claim
115 words
A photosensitive body for electrophotography, comprising in sequence: a conductive substrate; a charge transfer layer comprising selenium; a chargeable layer comprising selenium; an intermediate layer; and a surface protective layer, wherein the surface protective layer has a coefficient of thermal expansion, different than that of the chargeable layer, and the coefficient of thermal expansion of the intermediate layer changes on a gradient across the section of the intermediate layer from a value substantially equal to that of the chargeable layer at an edge of the intermediate layer adjacent the chargeable layer, to a value substantially equal to that of the surface protective layer at an edge of the intermediate layer adjacent the surface protective layer.
Claim 3
Dependent Claim
25 words
The photosensitive body of claim 1, wherein the coefficient of thermal expansion of the surface protective layer is less than that of the chargeable layer.
Claim 4
Dependent Claim
101 words
The photosensitive body of claim 2, wherein: the chargeable layer comprises a tellurium-selenium alloy wherein the tellurium concentration is between 30 and 50 weight %; the intermediate layer comprises an arsenic-selenium alloy wherein the arsenic concentration increases in a gradient across the section of the layer from an edge adjacent to the chargeable layer to an edge adjacent to the surface protective layer, so as to produce a corresponding decreasing gradient of the value of the coefficient of thermal expansion; and the surface protective layer comprises a material chosen from the group consisting of a selenium alloys, metal oxides and plastics.
Claim 5
Dependent Claim
17 words
The photosensitive body of claim 3, wherein the surface protective layer comprises Al 2 O 3 .
Claim 6
Dependent Claim
18 words
The photosensitive body of claim 3, wherein the surface protective layer comprises a mixture of nylon and polyurethane.
Claim 7
Dependent Claim
18 words
The photosensitive body of claim 3, wherein the surface protective layer comprises a As 2 Se 3 .
Claim 8
Dependent Claim
43 words
The photosensitive body of claim 4, wherein the thickness of the chargeable layer is between 0.1 and 1 μm, the thickness of the intermediate layer is between 1 and 5 μm, and the thickness of the surface protective layer is approximately 2 μm.
Claim 9
Dependent Claim
45 words
The photosensitive body of claim 5, wherein the thickness of the chargeable layer is between 0.1 and 1 μm, the thickness of the intermediate layer is between 1 and 5 μm, and the thickness of the surface protective layer is approximately 3 μm or less.
Claim 10
Dependent Claim
43 words
The photosensitive body of claim 6, wherein the thickness of the chargeable layer is between 0.1 and 1 μm, the thickness of the intermediate layer is between 1 and 5 μm, and the thickness of the surface protective layer is approximately 5 μm.
Claim 11
Dependent Claim
21 words
The photosensitive body of claim 3, wherein the arsenic concentration in the intermediate layer increases from 1.5 to 38.7 weight %.
Claim 12
Dependent Claim
36 words
The photosensitive body of claim 3, wherein there is disposed between the chargeable layer and the intermediate layer a first intermediate sublayer with a coefficient of thermal expansion substantially equal to that of the chargeable layer.
Claim 13
Dependent Claim
35 words
The photosensitive layer of claim 11, wherein the first intermediate sublayer comprises an arsenic-selenium alloy with 1.5 weight % arsenic, and the arsenic concentration in the intermediate layer increases from 1.5 to 38.7 weight %.
Claim 14
Dependent Claim
23 words
The photosensitive body of claim 12, wherein the thickness of both the intermediate layer and the first intermediate sublayer are approximately 1 μm.
Claim 15
Dependent Claim
38 words
The photosensitive body of claim 11, wherein there is disposed between the intermediate layer and the surface protective layer a second intermediate sublayer with a coefficient of thermal expansion substantially equal to that of the surface protective layer.
Claim 16
Dependent Claim
36 words
The photosensitive body of claim 14, wherein the second intermediate sublayer comprises an arsenic-selenium alloy of approximately 38.7 weight % arsenic, and the arsenic concentration in the intermediate layer increases from 1.5 to 38.7 weight %.
Claim 17
Dependent Claim
27 words
The photosensitive body of claim 15, wherein the thickness of the first intermediate sublayer, the intermediate layer, and the second intermediate sublayer are each approximately 1 μm.
References Cited (Backward Citations)
US4710442A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-11-13 | 1993-05-15 | 1993-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-13 | 1997-05-15 | 1997-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-13 | 2001-05-15 | 2001-11-14 | $7700.00 | Window Closed / Lapsed |