Patent US5270786A successfully refreshed from Google Patents.
US5270786A
Expired / Lapsed
US
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Developing device using developing roller having specific structure
Assignee: Toshiba Corp
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Filing: 1991-05-31
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Granted: 1993-12-14
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Expires: 2011-05-31
Abstract
Abstract A device for developing a latent image on an image carrier is used in an image forming apparatus. The developing device includes a developing roller, located to contact with the image carrier, for supplying a developing agent to the image carrier, and a blade, located to face the developing roller, for forming a developing agent layer of the developing agent supplied to the image carrier on the developing roller. The developing roller comprises an urethane rubber layer and a conductive urethane resin layer located around the rubber layer, in which the thickness T [μm] of the conductive resin layer satisfies the formula, 3×Rz=T=1OO when the maximum surface roughness of the rubber layer is taken in Rz [μm]. in addition, the respective elongations (%) of the rubber and resin layers L e and L 1 , satisfy the formula L e -L 1 ≦200.
Inventors
- 👤 Kazuhiko Kikuchi
- 👤 Naruhito Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:23
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0806; G03G15/0818
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
108 words
A developing roller used for supplying a developing agent to an image carrier, comprising: an elastic layer made of urethane rubber for obtaining a predetermined nip width between the developing roller and the image carrier; and a conductive layer made of urethane resin coated on the elastic layer for charging the developing agent; wherein the conductive has a thickness T (μm) which satisfies the formula, × Rz≦T≦100 when the maximum surface roughness of the elastic layer is Rz (μm), and the elastic layer and the conductive layer satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof.
Claim 2
Dependent Claim
108 words
A developing roller used for supplying a developing agent to an image carrier, comprising: an elastic layer made of urethane rubber for obtaining a predetermined nip width between the developing roller and the image carrier; and a conductive layer made of urethane resin coated on the elastic layer for charging the developing agent; wherein the conductive has a thickness T (μm) which satisfies the formula, × Rz≦T≦100 when the maximum surface roughness of the elastic layer is Rz (μm), and the elastic layer and the conductive layer satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof.
Claim 3
Dependent Claim
23 words
The developing roller of claim 1, wherein the elastic layer has a compression permanent deformation [%] in the range of 10% or less.
Claim 4
Independent Claim
134 words
A device for developing a latent image on an image carrier, comprising: roller means, located to contact with the image carrier, for supplying a developing agent to the image carrier; and means for forming a developing agent layer of the developing agent supplied to the image carrier on the roller means; the roller means comprising an elastic layer made of urethane rubber and a conductive layer made of urethane resin coated on the elastic layer, in which the thickness T (μm) of the conductive layer satisfies the formula, 3×Rz≦T≦100 when the maximum surface roughness of the elastic layer is Rz (μm), and the elastic layer and the conductive layer of the roller means satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof.
Claim 5
Independent Claim
134 words
A device for developing a latent image on an image carrier, comprising: roller means, located to contact with the image carrier, for supplying a developing agent to the image carrier; and means for forming a developing agent layer of the developing agent supplied to the image carrier on the roller means; the roller means comprising an elastic layer made of urethane rubber and a conductive layer made of urethane resin coated on the elastic layer, in which the thickness T (μm) of the conductive layer satisfies the formula, 3×Rz≦T≦100 when the maximum surface roughness of the elastic layer is Rz (μm), and the elastic layer and the conductive layer of the roller means satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof.
Claim 6
Dependent Claim
26 words
The device of claim 3, wherein the elastic layer of the roller means has a compression permanent deformation [%] in the range of 10% or less.
Claim 7
Dependent Claim
128 words
A developing roller used for supplying a developing agent to an image carrier, comprising: an elastic layer made of urethane rubber for obtaining a predetermined nip width between the developing roller and the image carrier; and a conductive layer made of urethane resin coated on the elastic layer for charging the developing agent; wherein the conductive layer has a thickness T (μm) which satisfies the formula, 3×Rz≦T≦100 when the maximum surface roughness of the elastic layer is taken in Rz (μm), the elastic layer and the conductive layer satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof, and the elastic layer and the conductive layer respectively have a resistance value of less than 1×10 6 (Ω·cm).
Claim 8
Dependent Claim
128 words
A developing roller used for supplying a developing agent to an image carrier, comprising: an elastic layer made of urethane rubber for obtaining a predetermined nip width between the developing roller and the image carrier; and a conductive layer made of urethane resin coated on the elastic layer for charging the developing agent; wherein the conductive layer has a thickness T (μm) which satisfies the formula, 3×Rz≦T≦100 when the maximum surface roughness of the elastic layer is taken in Rz (μm), the elastic layer and the conductive layer satisfy the formula, L.sub.e -L.sub.l ≦200 where L e and L l denote the respective elongations (%) of the materials thereof, and the elastic layer and the conductive layer respectively have a resistance value of less than 1×10 6 (Ω·cm).
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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) | 1996-12-13 | 1997-06-14 | 1997-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-13 | 2001-06-14 | 2001-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-13 | 2005-06-14 | 2005-12-14 | $7700.00 | Window Closed / Lapsed |