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US4960667A Expired / Lapsed US ⏱️ 0.0 years remaining

Positively charged black liquid electrophotographic developer compositions

Assignee: Xerox Corp
•
Filing: 1988-06-06
•
Granted: 1990-10-02
•
Expires: 2008-06-06
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Abstract

Abstract A positively charged liquid developer composition comprised of resin particles, a hydrocarbon, laked carbon black particles, and a charge director.

Inventors

  • 👤 Raymond W. Wong
  • 👤 Stephan Drappel
  • 👤 Melvin D. Croucher

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 02:39
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/122; G03G9/13; G03G9/131; G03G9/135; G03G9/1355

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 26 words
A positively charged liquid developer composition comprised of a hydrocarbon, toner particles consisting essentially of a resin and laked carbon black particles, and a charge director.
Claim 2
Dependent Claim 26 words
A positively charged liquid developer composition comprised of a hydrocarbon, toner particles consisting essentially of a resin and laked carbon black particles, and a charge director.
Claim 3
Dependent Claim 34 words
A developer composition in accordance with claim 1 wherein the resin particles are selected from the group consisting of copolymers of polyethylene and methacrylic acid, copolymers of polyethylene and vinyl acetate, and mixtures thereof.
Claim 4
Dependent Claim 26 words
A developer composition in accordance with claim 1 wherein a carbon black laked with crystal violet precipitated onto the surface thereof with molybdic acid is selected.
Claim 5
Dependent Claim 29 words
A composition in accordance with claim 1 wherein the charge director is selected from the group consisting of zirconium octoate, iron naphthenate, a polyisobutylene based polyester, and mixtures thereof.
Claim 6
Dependent Claim 24 words
A composition in accordance with claim 1 wherein the lake carbon black is selected from the group consisting of Toner 8200 and Toner 8500.
Claim 7
Dependent Claim 25 words
A composition in accordance with claim 1 wherein the charge director is present in an amount of from about 0.01 to about 2.0 weight percent.
Claim 8
Dependent Claim 25 words
A composition in accordance with claim 1 wherein the charge director is present in an amount of from about 0.02 to about 0.2 weight percent.
Claim 9
Dependent Claim 23 words
A composition in accordance with claim 1 wherein the resin is a polymer comprised of polyethylene copolymerized with methacrylic acid or vinyl acetate.
Claim 10
Dependent Claim 26 words
A composition in accordance with claim 8 wherein the polyethylene is present in an amount of from about 0.5 percent to about 6 percent by weight.
Claim 11
Dependent Claim 24 words
A composition in accordance with claim 1 wherein the developer composition has an average particle diameter of from about 2 to about 6 microns.
Claim 12
Dependent Claim 38 words
A method of imaging which comprises generating an image in an electrophotographic imaging apparatus; subsequently developing this image with the composition of claim 1; thereafter transferring the image to a suitable substrate; and permanently affixing the image thereto.
Claim 13
Dependent Claim 28 words
A method of imaging in accordance with claim 11 wherein the developed image exhibited a transfer efficiency of from about 80 to about 99 percent from the substrate.
Claim 14
Dependent Claim 14 words
A method of imaging in accordance with claim 12 wherein the substrate is paper.
Claim 15
Dependent Claim 24 words
A composition in accordance with claim 1 wherein the developer is of an average particle diameter of from about 2 to about 3 microns.
Claim 16
Dependent Claim 14 words
A composition in accordance with claim 1 wherein the hydrocarbon is a petroleum distillate.
Claim 17
Dependent Claim 46 words
A composition in accordance with claim 1 wherein the toner particles contain the resin in an amount of from about 75 to about 99 percent by weight and the laked carbon black particles in an amount of from about 1 to about 25 percent by weight.
Claim 18
Dependent Claim 46 words
A composition in accordance with claim 1 wherein the toner particles contain the resin in an amount of from about 78 to about 88 percent by weight and the laked carbon black particles in an amount of from about 12 to about 22 percent by weight.

References Cited (Backward Citations)

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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) 1993-10-01 1994-04-02 1994-10-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-10-01 1998-04-02 1998-10-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-10-01 2002-04-02 2002-10-02 $7700.00 Window Closed / Lapsed

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