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US3851964A Expired / Lapsed US ⏱️ 0.0 years remaining

Contact transfer electrostatic copying apparatus

Assignee: Savin Business Machines Corp
•
Filing: 1973-05-14
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Granted: 1974-12-03
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Expires: 1993-05-14
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Abstract

Abstract An electrophotographic copying machine employs a method of contact transfer of developed electrostatic images. A moving photoconductive surface is charged and exposed to a pattern of light and shade as done in known electrophotographic processes, and the latent image is developed with a liquid developer which carries a toner which is tacky-that is, one that has adhesive properties. The developed image with the toner in tacky state is contacted with sheet material such as paper, which has greater affinity for the tacky toner than the photoconductive surface from which the image is transferred. After the image is transferred to the sheet material the toner quickly loses its tackiness and dries to a hard scuff-resistant surface. Transfer of the tacky toner may be facilitated by heating the sheet material before contact is made between it and the developed image.

Inventors

  • 👤 I Smith
  • 👤 P Hastwell
  • 👤 M Vermeulen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 17:24
CPC Classifications
G; G03; G03G; G03G7/00; G03G7/0006; G03G7/002; G03G7/0026; G03G7/004; G03G13/00; G03G13/14; G03G13/16; G03G15/00; G03G15/22; G03G15/26; G03G15/263; G03G15/28; G03G15/30; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0557; G03G5/0575; G03G5/0578; G03G5/14; G03G5/147; G03G9/00; G03G9/08; G03G9/12

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 109 words
IN AN ELECTROPHOTOGRAPHIC APPARATUS A CONDUCTIVE CARRIER, A PHOTOCONDUCTIVE SURFACE SUPPORTED BY SAID CARRIER, MEANS FOR CHARGING SAID PHOTOCONDUCTIVE SURFACE, MEANS FOR EXPOSING SAID CHARGED SURFACE TO A PATTERN OF LIGHT AND SHADE OF AN IMAGE TO BE REPRODUCED TO FORM A LATENT ELECTROSTATIC IMAGE, A TANK FOR HOLDING LIQUID TONER, MEANS FOR SUBJECTING SAID LATENT ELECTROSTIC IMAGE TO THE ACTION OF SAID LIQUID TONER TO FORM A TACKY IMAGE, TRANSFER MEANS FOR BRINGING SHEET MATERIAL INTO CONTACT WITH THE TACKY IMAGE WHILE ON SAID PHOTOCONDUCTIVE SURFACE TO TRANSFER THE DEVELOPED IMAGE THERETO, AND MEANS FOR HEATING SAID SHEET MATERIAL BEFORE SAID SHEET MATERIAL ARRIVES AT THE CONTACTING MEANS.
Claim 2
Dependent Claim 109 words
IN AN ELECTROPHOTOGRAPHIC APPARATUS A CONDUCTIVE CARRIER, A PHOTOCONDUCTIVE SURFACE SUPPORTED BY SAID CARRIER, MEANS FOR CHARGING SAID PHOTOCONDUCTIVE SURFACE, MEANS FOR EXPOSING SAID CHARGED SURFACE TO A PATTERN OF LIGHT AND SHADE OF AN IMAGE TO BE REPRODUCED TO FORM A LATENT ELECTROSTATIC IMAGE, A TANK FOR HOLDING LIQUID TONER, MEANS FOR SUBJECTING SAID LATENT ELECTROSTIC IMAGE TO THE ACTION OF SAID LIQUID TONER TO FORM A TACKY IMAGE, TRANSFER MEANS FOR BRINGING SHEET MATERIAL INTO CONTACT WITH THE TACKY IMAGE WHILE ON SAID PHOTOCONDUCTIVE SURFACE TO TRANSFER THE DEVELOPED IMAGE THERETO, AND MEANS FOR HEATING SAID SHEET MATERIAL BEFORE SAID SHEET MATERIAL ARRIVES AT THE CONTACTING MEANS.
Claim 3
Dependent Claim 26 words
Apparatus as in claim 1 in which said means for heating said sheet material is positioned to direct heat against the rear of said sheet material.
Claim 4
Dependent Claim 15 words
Apparatus as in claim 1 including means for removing excess toner from said photoconductive surface.
Claim 5
Dependent Claim 19 words
Apparatus as in claim 1 including means for cleaning said photoconductive surface after the operation of said transfer means.
Claim 6
Dependent Claim 16 words
Apparatus as in claim 1 including means for heating said tacky image to increase its tackiness.
Claim 7
Dependent Claim 21 words
Apparatus as in claim 1 including means for heating said transferred image on said sheet material to fix the same thereto.
Claim 8
Dependent Claim 21 words
Apparatus as in claim 1 in which said photoconductive surface has less affinity for the tacky image than said sheet material.

References Cited (Backward Citations)

US3275436A Cited
US3176653A Cited
US3493412A Cited
US3592642A Cited
US3591276A Cited
US3698314A Cited
US3716360A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-12-02 1978-06-03 1978-12-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-12-02 1982-06-03 1982-12-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-12-02 1986-06-03 1986-12-03 $7700.00 Window Closed / Lapsed

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