EP0329366A1
Expired / Lapsed
EP
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Charging member
Assignee: Canon Inc
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Filing: 1989-02-14
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Granted: —
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Expires: 2009-02-14
Abstract
Abstract There is provided a charging member comprising an electroconductive substract (2), and an elastic layer (3), an electroconductive layer (4) and a resistance layer (5) disposed in this order on the substrate. Such charging member provides good contact with a photosensitive member (7), to provide good image quality without causing an image defect such as white spot based on charging unevenness. Further, the charging member causes no leak even when the photosensitive member has a pin hole, and reduced the level of noise based on an AC voltage to be applied thereto.
Inventors
- 👤 Hisami Tanaka
- 👤 Masami Okunuki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 17:08
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0233; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/102
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
25 words
A charging member, comprising: an electroconductive substrate, and an elastic layer, an electroconductive layer and a resistance layer disposed in this order on the substrate.
Claim 2
Dependent Claim
25 words
A charging member, comprising: an electroconductive substrate, and an elastic layer, an electroconductive layer and a resistance layer disposed in this order on the substrate.
Claim 3
Dependent Claim
19 words
A member according to Claim 1, wherein the elastic layer has a rubber hardness of 35 degrees or smaller.
Claim 4
Dependent Claim
23 words
A member according to claim 2, wherein the elastic layer has a rubber hardness of in the range of 12 to 25 degrees.
Claim 5
Dependent Claim
22 words
A member according to any of claims 1 to 3, wherein the elastic layer has a thickness of 1.5 mm or larger.
Claim 6
Dependent Claim
22 words
A member according to claim 4, wherein the elastic layer has a thickness in the thickness of 3 mm to 13 mm.
Claim 7
Dependent Claim
18 words
A member according to any preceding claim, wherein the elastic layer comprises a rubber or a thermoplastic elastomer.
Claim 8
Dependent Claim
20 words
A member according to any preceding claim, wherein the electroconductive layer has a volume resistivity of 10⁷ ohm.cm or lower.
Claim 9
Dependent Claim
24 words
A member according to claim 7, wherein the electroconductive layer has a volume resistivity of in the range of 10⁻² ohm.cm to 10⁶ ohm.cm.
Claim 10
Dependent Claim
19 words
A member according to any preceding claim, wherein the electroconductive layer has a thickness of 3 mm or smaller.
Claim 11
Dependent Claim
22 words
A member according to claim 9, wherein the electroconductive layer has a thickness in the range of 20 microns to 1 mm.
Claim 12
Dependent Claim
19 words
A member according to any preceding claim, wherein the electroconductive layer comprises a resin containing electroconductive particles dispersed therein.
Claim 13
Dependent Claim
22 words
A member according to any preceding claim, wherein the resistance layer has a higher volume resistivity than that of the electroconductive layer.
Claim 14
Dependent Claim
29 words
A member according to claim 12, wherein the resistance layer has a higher volume resistivity than that of the electroconductive layer by a factor of one to six figures.
Claim 15
Dependent Claim
24 words
A member according to any preceding claim, wherein the resistance layer has a volume resistivity in the range of 10⁶ ohm.cm to 10¹² ohm.cm.
Claim 16
Dependent Claim
23 words
A member according to claim 14, wherein the resistance layer has a volume resistivity in the range of 10⁷ ohm.cm to 10¹¹ ohm.cm.
Claim 17
Dependent Claim
23 words
A member according to any preceding claim, wherein the resistance layer has a thickness in the range of 1 micron to 500 microns.
Claim 18
Dependent Claim
22 words
A member according to claim 16, wherein the resistance layer has a thickness in the range of 50 microns to 200 microns.
Claim 19
Dependent Claim
24 words
A member according to any preceding claim, wherein the resistance layer comprises a semiconductive resin, or an insulating resin containing electroconductive particles dispersed therein.
Claim 20
Dependent Claim
20 words
A member according to claim 18, wherein the resistance layer consists essentially of a resinous material comprising a semiconductive resin.
Claim 21
Dependent Claim
25 words
A member according to any preceding claim, wherein the resistance layer has a two-layer structure comprising an internal resistance layer and a surface resistance layer.
Claim 22
Dependent Claim
14 words
A member according to claim 20, wherein the internal resistance layer contains a plasticizer.
Claim 23
Dependent Claim
18 words
A member according to claim 20 or 21, wherein the surface resistance layer contains electroconductive particles dispersed therein.
Claim 24
Dependent Claim
26 words
A member according to any of claims 20 to 22, wherein the surface resistance layer has a smaller thickness than that of the internal resistance layer.
Claim 25
Dependent Claim
27 words
A member according to any of claims 20 to 23, wherein the surface resistance layer has a lower volume resistivity than that of the internal resistance layer.
Claim 26
Dependent Claim
19 words
A member according to any of claims 20 to 24, wherein the internal resistance layer comprises a semiconductive rubber.
Claim 27
Dependent Claim
28 words
A member according to any of claims 20 to 25, wherein the surface resistance layer comprises a semiconductive resin, or an insulating resin containing electroconductive particles dispersed therein.
Claim 28
Dependent Claim
38 words
A member according to any of claims 20 to 26, wherein the internal resistance layer has a thickness of 1 micron to 450 microns and the surface resistance layer has a thickness of 0.1 micron to 50 microns.
Claim 29
Dependent Claim
33 words
A member according to claim 27, wherein the internal resistance layer has a thickness of 50 microns to 200 microns; the surface resistance layer has a thickness of 1 micron to 30 microns.
Claim 30
Dependent Claim
15 words
A member according to any preceding claim, which is in the form of a roller.
Claim 31
Dependent Claim
46 words
A contact charging method, comprising: providing a charging member according to any preceding claim; providing a charge-receiving member disposed in contact with the charging member; and applying a voltage to the charging member by means of an external power supply, thereby to charge the charge-receiving member.
Claim 32
Dependent Claim
49 words
A contact charging method according to claim 30, wherein the voltage externally applied to the charging member comprises a pulsation voltage comprising a superposition of a DC voltage of ± 200 V to ± 1500 V and an AC voltage having a peak-to-peak voltage of 2000 V or below.
Claim 33
Dependent Claim
27 words
An electrophotographic apparatus, comprising: a charging member according to any of claims 1 to 29; and an electrophotographic photosensitive member disposed in contact with the charging member.
Claim 34
Dependent Claim
91 words
An apparatus according to claim 32, which further comprises image exposure means for exposing the photosensitive member to form a latent image; developing means for developing the latent image with a toner to form a transferable toner image on the surface of the photosensitive member, transfer charging means for transferring the toner image to a transfer-receiving material, and cleaning means for removing a residual toner; said charging member, image exposure means, developing means, transfer means and cleaning means being disposed in this order along the moving direction of the photosensitive member.
Claim 35
Dependent Claim
26 words
An apparatus according to claim 32 or 33, wherein the photosensitive member comprises an electroconductive substrate and a photosensitive layer disposed thereon comprising an organic photoconductor.
References Cited (Backward Citations)
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