US5066989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning method for use in copy apparatus and toner used therefor
Assignee: Panasonic Holdings Corp
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Filing: 1990-09-06
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Granted: 1991-11-19
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Expires: 2010-09-06
Abstract
Abstract A cleaning method is provided for use in a color electrophotographic apparatus in which color toner images formed by using a plurality of color toners on a photosensitive medium by repeating charging, exposure and reverse-developing steps are transferred to a sheet of paper at one stroke. The toners include color toners and a black toner. Each of the color toners is a toner for a DC electric field jump developing method which serves to develop without making contact with the photosensitive medium. The black toner is a toner for a two-component magnetic brush developer which is mixed with a carrier to be used. The two-component magnetic brush developer is used both as a developer serving to develop in contract with the photosensitive medium and a cleaning agent serving to clean the toners remaining on the photosensitive medium after the transfer operation. Further, the color toners and black toner are charged, when mixed with the two-component magnetic brush developer, to have a polarity which is the same as the polarity thereof at the time of developing.
Inventors
- 👤 Hajime Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:53
CPC Classifications
G; G03; G03G; G03G21/00; G03G15/00; G03G15/01; G03G15/0105; G03G13/00; G03G13/06; G03G13/08; G03G13/09; G03G21/0005; G03G21/0047; G03G2221/00; G03G2221/0005
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
153 words
A cleaning method for use in a color electrophotographic apparatus in which color toner images formed by using a plurality of color toners on a photosensitive medium by repeating charging, exposure and reversal developing steps are transferred to a sheet of paper at one stroke, the method comprising the steps of: providing said toners including color toners and a black toner, each of said color toners being a toner for a DC electric field jump developing method which serves to develop without making contract with the photosensitive medium and said black toner being a toner for a two-component magnetic brush developer and being mixed with a carrier to be charged, and using said two-component brush developer as a cleaning agent serving to clean the toners remaining on the photosensitive medium after a transfer operation, said two-component brush developer being also used as a developer serving to develop in contract with the photosensitive medium.
Claim 2
Dependent Claim
153 words
A cleaning method for use in a color electrophotographic apparatus in which color toner images formed by using a plurality of color toners on a photosensitive medium by repeating charging, exposure and reversal developing steps are transferred to a sheet of paper at one stroke, the method comprising the steps of: providing said toners including color toners and a black toner, each of said color toners being a toner for a DC electric field jump developing method which serves to develop without making contract with the photosensitive medium and said black toner being a toner for a two-component magnetic brush developer and being mixed with a carrier to be charged, and using said two-component brush developer as a cleaning agent serving to clean the toners remaining on the photosensitive medium after a transfer operation, said two-component brush developer being also used as a developer serving to develop in contract with the photosensitive medium.
Claim 3
Dependent Claim
178 words
A set of toners for use in a color electrophotographic apparatus in which color toner images formed by using a plurality of color toners on a photosensitive medium by repeating charging, exposure and inversion-developing steps are transferred to a sheet of paper at one stroke, wherein said toners include color toners and a black toner, each of said color toners being a toner for a DC electric field jump developing method which serves to develop without making contact with the photosensitive medium and said black toner being a toner for a two-component magnetic brush developer and being mixed with a carrier to be charged, said two-component magnetic brush developer being used both as a developer serving to develop in contact with the photosensitive medium and a cleaning agent serving to clean the toners remaining on the photosensitive medium after a transfer operation, and wherein said color toners and said black toner are charged, when mixed with said two-component magnetic brush developer, to have a polarity which is the same as the polarity thereof at the time of developing.
Claim 4
Dependent Claim
178 words
A set of toners for use in a color electrophotographic apparatus in which color toner images formed by using a plurality of color toners on a photosensitive medium by repeating charging, exposure and inversion-developing steps are transferred to a sheet of paper at one stroke, wherein said toners include color toners and a black toner, each of said color toners being a toner for a DC electric field jump developing method which serves to develop without making contact with the photosensitive medium and said black toner being a toner for a two-component magnetic brush developer and being mixed with a carrier to be charged, said two-component magnetic brush developer being used both as a developer serving to develop in contact with the photosensitive medium and a cleaning agent serving to clean the toners remaining on the photosensitive medium after a transfer operation, and wherein said color toners and said black toner are charged, when mixed with said two-component magnetic brush developer, to have a polarity which is the same as the polarity thereof at the time of developing.
Claim 5
Dependent Claim
25 words
A set of toners according to claim 2, wherein a binder resin sued for said color toners and said black toner is a styrene-acryl resin.
Claim 6
Dependent Claim
25 words
A set of toners according to claim 2, wherein a binder resin used for said color toners and said black toner is a polyester resin.
Claim 7
Dependent Claim
25 words
A set of toners according to claim 2, wherein a binder resin used for said color toners and said black toner is an epoxy resin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |