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US3871879A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming colored copied image

Assignee: Ricoh Co Ltd
•
Filing: 1973-12-28
•
Granted: 1975-03-18
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Expires: 1993-12-28
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Abstract

Abstract Method for obtaining a colored copied image by repeating a cycle consisting of the process of forming an electrostatic latent image on an electrophotographic copying material having a photoconductive layer, the process of transferring said electrostatic latent image onto a transfer sheet having a dielectric layer and the process of developing the thus transferred electrostatic latent image for each primary color of the colored original image, an improved method of forming a colored copied image free of fog which method comprises employing a transfer sheet having a dielectric layer containing a photoconductive substance and interposing an additional process of applying active radiant rays to the whole surface of said dielectric layer upon which the image is developed between said cycles, and a transfer sheet useful in the method.

Inventors

  • 👤 Akio Arai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 19:28
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/0202; G03G13/00; G03G13/01; G03G5/10; G03G5/12

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 112 words
IN A METHOD OF FORMING A COLORED COPIED IMAGE ON A TRANSFER SHEET BY REPEATING A CYCLE COMPRISING (1) FORMING AN ELECTROSTATIC LATENT IMAGE ON AN ELECTROPHOTOGRAPHIC COPYING MATERIAL HAVING A PHOTOCONDUCTIVE LAYER, (2) TRANSFERRING SAID ELECTROSTATIC LATENT IMAGE ONTO A TRANSFER SHEET HAVING A DIELECTRIC LAYER WHICH IS AN INSULATING RESIN AND (3) DEVELOPING THE THUS TRANSFERRED ELECTROSTATIC LATENT IMAGE FOR EACH PRIMARY COLOR CONSTITUTING THE COLORED ORIGINAL IMAGE; THE IMPROVEMENT COMPRISING EMPLOYING A TRANSFER SHEET HAVING A PHOTOCONDUCTIVE DIELECTRIC LAYER UPON WHICH THE IMAGE IS DEVELOPED AND APPLYING ACTIVE RADIANT RAYS TO THE WHOLE SURFACE OF SAID DIELECTRIC LAYER BETWEEN SUCCESSIVE CYCLES TO DISSIPATE RESIDUAL CHARGE FROM A PREVIOUS CYCLE.
Claim 2
Dependent Claim 112 words
IN A METHOD OF FORMING A COLORED COPIED IMAGE ON A TRANSFER SHEET BY REPEATING A CYCLE COMPRISING (1) FORMING AN ELECTROSTATIC LATENT IMAGE ON AN ELECTROPHOTOGRAPHIC COPYING MATERIAL HAVING A PHOTOCONDUCTIVE LAYER, (2) TRANSFERRING SAID ELECTROSTATIC LATENT IMAGE ONTO A TRANSFER SHEET HAVING A DIELECTRIC LAYER WHICH IS AN INSULATING RESIN AND (3) DEVELOPING THE THUS TRANSFERRED ELECTROSTATIC LATENT IMAGE FOR EACH PRIMARY COLOR CONSTITUTING THE COLORED ORIGINAL IMAGE; THE IMPROVEMENT COMPRISING EMPLOYING A TRANSFER SHEET HAVING A PHOTOCONDUCTIVE DIELECTRIC LAYER UPON WHICH THE IMAGE IS DEVELOPED AND APPLYING ACTIVE RADIANT RAYS TO THE WHOLE SURFACE OF SAID DIELECTRIC LAYER BETWEEN SUCCESSIVE CYCLES TO DISSIPATE RESIDUAL CHARGE FROM A PREVIOUS CYCLE.
Claim 3
Dependent Claim 19 words
A method according to claim 1, wherein said dielectric layer comprises an inorganic photoconductive pigment in an insulating resin.
Claim 4
Dependent Claim 33 words
A method according to claim 2, wherein the amount of said inorganic photoconductive pigment is in the range of 0.3-5 parts by weight relative to 1 part by weight of said insulating resin.
Claim 5
Dependent Claim 19 words
A method according to claim 1, wherein said dielectric layer comprises an organic photoconductive pigment in an insulating resin.
Claim 6
Dependent Claim 33 words
A method according to claim 4, wherein the amount of said organic photoconductive pigment is in the range of 0.3-5 parts by weight relative to 1 part by weight of said insulating resin.
Claim 7
Dependent Claim 30 words
A method according to claim 1, wherein said dielectric layer of the transfer sheet is an organic photoconductive insulating resin and said dielectric layer further contains an inorganic white pigment.
Claim 8
Dependent Claim 28 words
A method according to claim 6, wherein the ratio of said inorganic white pigment to said organic photoconductive insulating resin by weight is in the range of 0.1-5.
Claim 9
Dependent Claim 14 words
A method according to claim 1, wherein said dielectric layer further contains a sensitizer.
Claim 10
Dependent Claim 39 words
A method according to claim 8, wherein the amount of said sensitizer is in the range of 5 X 10 6 mol to 5 X 10 4 mol relative to the amount of 100 g of said photoconductive substance.
Claim 11
Dependent Claim 24 words
A method according to claim 1, wherein said active radiant rays are applied until the residual electric charge on the dielectric layer is extinguished.

References Cited (Backward Citations)

US3666458A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-03-17 1978-09-16 1979-03-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-03-17 1982-09-16 1983-03-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-03-17 1986-09-16 1987-03-18 $7700.00 Window Closed / Lapsed

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