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US4710015A Expired / Lapsed US ⏱️ 0.0 years remaining

Developing apparatus

Assignee: Ricoh Co Ltd
•
Filing: 1986-10-28
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Granted: 1987-12-01
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Expires: 2006-10-28
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Abstract

Abstract A developing apparatus is disclosed, in which a developing roller composed of an insulating layer, a dielectric layer and an electrically conductive substrate is made in contact with a photosensitive member to develope a latent image on the member. The dielectric layer is formed of a material whose resistivity-specific dielectricity characteristics satisfies a certain condition which is suitable for medial tone development or binary tone development.

Inventors

  • 👤 Fuchio Takeda
  • 👤 Hiroyuki Matsushiro
  • 👤 Kazuo Kobayashi
  • 👤 Toshio Kaneko

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 01:00
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0806; G03G15/0818

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 110 words
A developing apparatus of the type in which a thin toner layer is formed on a toner carrier such that said toner carrier is in contact with a latent image carrier through said toner layer to devlope a latent image on said latent image carrier, characterized by that said toner carrier is composed of an electrically conductive substrate an elastic dielectric layer formed on said substrate and supported thereby and an insulating layer formed on said elastic dielectric layer and that said elastic dielectric layer is formed of a material which satisfies log.sub.10 y<0.15x+7.5 (x>1) where x is specific dielectricity of said material and y is resistivity of said material.
Claim 2
Dependent Claim 110 words
A developing apparatus of the type in which a thin toner layer is formed on a toner carrier such that said toner carrier is in contact with a latent image carrier through said toner layer to devlope a latent image on said latent image carrier, characterized by that said toner carrier is composed of an electrically conductive substrate an elastic dielectric layer formed on said substrate and supported thereby and an insulating layer formed on said elastic dielectric layer and that said elastic dielectric layer is formed of a material which satisfies log.sub.10 y<0.15x+7.5 (x>1) where x is specific dielectricity of said material and y is resistivity of said material.
Claim 3
Dependent Claim 111 words
A developing apparatus of the type in which a thin toner layer is formed on a toner carrier such that said toner carrier is in contact with a latent image carrier through said thin toner layer to develope a latent image on said latent image carrier, characterized by that said toner carrier is composed of an electrically conductive substrate, an elastic dielectric layer formed on said substrate and supported thereby and an insulating layer formed on said elastic dielectric layer and that said elastic dielectric layer is formed of a material which satisfies 0.15x+5.5<log.sub.10 y<0.15x+8 (x>1) where x is specific dielectricity of said material and y is resistivity of said material.
Claim 4
Dependent Claim 111 words
A developing apparatus of the type in which a thin toner layer is formed on a toner carrier such that said toner carrier is in contact with a latent image carrier through said thin toner layer to develope a latent image on said latent image carrier, characterized by that said toner carrier is composed of an electrically conductive substrate, an elastic dielectric layer formed on said substrate and supported thereby and an insulating layer formed on said elastic dielectric layer and that said elastic dielectric layer is formed of a material which satisfies 0.15x+5.5<log.sub.10 y<0.15x+8 (x>1) where x is specific dielectricity of said material and y is resistivity of said material.

References Cited (Backward Citations)

US3993023A Cited
US3993024A Cited
US4425382A Cited
US4593480A Cited
US4505573A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-30 1991-06-01 1991-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-30 1995-06-01 1995-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-30 1999-06-01 1999-12-01 $7700.00 Window Closed / Lapsed

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