US5162608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing process and apparatus using a magnetic roller including a sleeve having an electret layer
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1991-04-17
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Granted: 1992-11-10
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Expires: 2011-04-17
Abstract
Abstract A developing process for supplying a developer to a support having an electrostatic latent image thereon by using a developer-delivering member having an electret layer and carrying out the development so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU1## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image are and E S represents the surface potential of the electret layer, is in the range of from 0.01 to 0.6. According to this process, an image having a high density with no fog can be formed without applying a developing bias voltage.
Inventors
- 👤 Masanori Matsuda
- 👤 Takeshi Hori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:26
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; G03G15/0921; G03G15/0928; G03G13/00; G03G13/06; G03G13/08; G03G13/09
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
146 words
An electrophotographic developing process comprising supplying a magnetic developer to a developer-delivering member having magnets disposed in the interior thereof and also having on the surface thereof an electret layer having a polarity reverse to the polarity of developer particles, to form a magnetic brush of the magnetic developer, and bringing the magnetic brush into contact with a support having an electrostatic latent image thereon, to effect the development of the electrostatic latent image, wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU7## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the electret layer, is in the range of from 0.01 to 0.6.
Claim 2
Dependent Claim
146 words
An electrophotographic developing process comprising supplying a magnetic developer to a developer-delivering member having magnets disposed in the interior thereof and also having on the surface thereof an electret layer having a polarity reverse to the polarity of developer particles, to form a magnetic brush of the magnetic developer, and bringing the magnetic brush into contact with a support having an electrostatic latent image thereon, to effect the development of the electrostatic latent image, wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU7## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the electret layer, is in the range of from 0.01 to 0.6.
Claim 3
Dependent Claim
28 words
A developing process according to claim 1, wherein the contact of the magnetic brush with the electrostatic latent image support is carried out without applying a bias voltage.
Claim 4
Dependent Claim
33 words
A developing process according to claim 1, wherein the magnetic developer is a two-component type developer comprising a magnetic carrier and a toner, or a one-component type magnetic toner containing a magnetic powder.
Claim 5
Dependent Claim
160 words
An electrophotographic developing process comprising supplying a magnetic developer to a developer-delivering member having magnets disposed in the interior thereof and also having on the surface thereof a laminate comprising a plurality of electret layers having the same or different polarities and having a polarity the same or reverse to the polarity of developer particles, to form a magnetic brush of the magnetic developer, and bringing the magnetic brush into contact with a support having an electrostatic latent image thereon, to effect the development of the electrostatic latent image, wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU8## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the laminate, is in the range of from 0.01 to 0.6.
Claim 6
Dependent Claim
160 words
An electrophotographic developing process comprising supplying a magnetic developer to a developer-delivering member having magnets disposed in the interior thereof and also having on the surface thereof a laminate comprising a plurality of electret layers having the same or different polarities and having a polarity the same or reverse to the polarity of developer particles, to form a magnetic brush of the magnetic developer, and bringing the magnetic brush into contact with a support having an electrostatic latent image thereon, to effect the development of the electrostatic latent image, wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU8## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the laminate, is in the range of from 0.01 to 0.6.
Claim 7
Dependent Claim
28 words
A developing process according to claim 4, wherein the contact of the magnetic brush with the electrostatic latent image support is carried out without applying a bias voltage.
Claim 8
Dependent Claim
33 words
A developing process according to claim 4, wherein the magnetic developer is a two-component type developer comprising a magnetic carrier and a toner, or a one-component type magnetic toner containing a magnetic powder.
Claim 9
Dependent Claim
130 words
In a developing process wherein a non-magnetic developer is electrically charged and supplied to the surface of a developer-delivering member having an electret layer having a polarity reverse to the charged polarity, then the developer is supplied to the surface of the supporting body having an electrostatic latent image, effecting an electrostatic latent image development, a developing process wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU9## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the electret layer, is in the range of from 0.01 to 0.6.
Claim 10
Dependent Claim
130 words
In a developing process wherein a non-magnetic developer is electrically charged and supplied to the surface of a developer-delivering member having an electret layer having a polarity reverse to the charged polarity, then the developer is supplied to the surface of the supporting body having an electrostatic latent image, effecting an electrostatic latent image development, a developing process wherein the development is carried out so that the effective fog-controlling field intensity ratio (A) defined by the following formula: ##EQU9## wherein E L represents the surface potential of the latent image area in the support having the electrostatic latent image area, E B represents the surface potential of the non-image area and E S represents the surface potential of the electret layer, is in the range of from 0.01 to 0.6.
Claim 11
Dependent Claim
126 words
A developing apparatus comprising a support for supporting an electrostatic image thereon, a mechanism for electrically charging a powdery developer and a developer-delivering member for supporting the charged powdery developer thereon and supplying the powdery developer to said support, wherein the developer-delivering member has an electret dielectric layer at least on the surface thereon, and the charge density of the electret dielectric layer is adjusted so that the fog-controlling charge density ratio (D) defined by the following formula: ##EQU10## wherein δ represents the charge density of the electret dielectric layer, δ B represents the charge density of the non-image area of said support and δ L represents the charge density of the image area of said support, is in the range of from 0.01 to 2.0.
Claim 12
Dependent Claim
126 words
A developing apparatus comprising a support for supporting an electrostatic image thereon, a mechanism for electrically charging a powdery developer and a developer-delivering member for supporting the charged powdery developer thereon and supplying the powdery developer to said support, wherein the developer-delivering member has an electret dielectric layer at least on the surface thereon, and the charge density of the electret dielectric layer is adjusted so that the fog-controlling charge density ratio (D) defined by the following formula: ##EQU10## wherein δ represents the charge density of the electret dielectric layer, δ B represents the charge density of the non-image area of said support and δ L represents the charge density of the image area of said support, is in the range of from 0.01 to 2.0.
Claim 13
Dependent Claim
27 words
A developing apparatus as set forth in claim 8, wherein the surface charge density of the electret layer is 10 -11 to 2×10 -7 C/cm 2 .
Claim 14
Dependent Claim
26 words
A developing apparatus as set forth in claim 8, wherein the thickness of the electret layer is in the range of from 0.005 to 2 mm.
Claim 15
Dependent Claim
23 words
A developing apparatus as set forth in claim 8, wherein the critical surface tension of the electret layer is lower than 31 dine/cm.
Claim 16
Dependent Claim
24 words
A developing apparatus as set forth in claim 8, wherein the average surface roughness (Rz) of the electret layer is at least 0.02 μm.
Claim 17
Dependent Claim
22 words
A developing apparatus as set forth in claim 8, wherein a plurality of electret layers are arranged to form an electret laminate.
Claim 18
Dependent Claim
25 words
A developing apparatus as set forth in claim 13, wherein the bonded surfaces of the electret layers of the electret laminate have the same polarity.
Claim 19
Dependent Claim
19 words
A developing apparatus as set forth in claim 13, wherein the electret laminate is formed on a conductive layer.
Claim 20
Dependent Claim
32 words
A developing apparatus as set forth in claim 8, wherein the developer is a two-component type or one-component type magnetic developer and the developer-delivering member has magnets disposed in the interior thereof.
Claim 21
Dependent Claim
16 words
A developing apparatus as set forth in claim 8, wherein the developer is a non-magnetic developer.
Claim 22
Dependent Claim
139 words
An electrophotographic developing apparatus comprising a support for supporting an electrostatic image, a mechanism for electrically charging a powdery developer and a developer-delivering member for supporting the charged powdery developer thereon and applying the charged powdery developer to said support, wherein the developer-delivering member has a laminate structure comprising an electret dielectric layer and a protecting dielectric layer formed on the surface of the electret dielectric layer, and the charge density of the electret dielectric layer is adjusted so that the fog-controlling charge density ratio (D) defined by the following formula: ##EQU11## wherein δ represents the charge density of the electret dielectric layer, δ B represents the charge density of the non-image area of said support and δ L represents the charge density of the image data of said support, is in the range of from 0.01 to 2.0.
Claim 23
Dependent Claim
139 words
An electrophotographic developing apparatus comprising a support for supporting an electrostatic image, a mechanism for electrically charging a powdery developer and a developer-delivering member for supporting the charged powdery developer thereon and applying the charged powdery developer to said support, wherein the developer-delivering member has a laminate structure comprising an electret dielectric layer and a protecting dielectric layer formed on the surface of the electret dielectric layer, and the charge density of the electret dielectric layer is adjusted so that the fog-controlling charge density ratio (D) defined by the following formula: ##EQU11## wherein δ represents the charge density of the electret dielectric layer, δ B represents the charge density of the non-image area of said support and δ L represents the charge density of the image data of said support, is in the range of from 0.01 to 2.0.
Claim 24
Dependent Claim
38 words
A developing apparatus as set forth in claim 18, wherein the outer surface of the electret dielectric layer is charged with a polarity reverse to the polarity of the charge polarity of the particles of the powdery developer.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-11-10 | 1996-05-11 | 1996-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-11-10 | 2000-05-11 | 2000-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-11-10 | 2004-05-11 | 2004-11-10 | $7700.00 | Window Closed / Lapsed |