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US4197211A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid electrophotographic developers

Assignee: Xerox Corp
•
Filing: 1974-10-01
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Granted: 1980-04-08
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Expires: 1994-10-01
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Abstract

Abstract Development of an electrostatic latent image is obtained with a chemically stable, nonaqueous, ambipolar, liquid developer comprising an oleaginous vehicle, solid colorant particles, a dispersant soluble in the liquid developer which is capable of substantially supressing background deposits, and a fixing agent miscible with the liquid which penetrates the copy paper.

Inventors

  • 👤 Alan B. Amidon
  • 👤 Joseph Mammino
  • 👤 Robert M. Ferguson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 10:12
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/131

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 194 words
A chemically stable, nonaqueous, ambipolar, absorptive drying electrostatographic liquid developer of low volatility having a resistivity of from about 10 8 to 10 15 ohm cm comprising from about 30 weight percent to about 85 weight percent of an oleaginous liquid vehicle from about 5 weight percent to about 60 weight percent of a particulate colorant which is insoluble in at least one liquid present in the liquid developer; from about 1 weight percent to about 35 weight percent of a dispersant which is soluble in the oleaginous vehicle and which is capable of substantially supressing background deposits, said dispersant comprising copolymers of alkyl vinyl ethers and maleic anhydride where alkyl substituent of the vinyl ether has a carbon chain length of from 14 to 20 carbon atoms, and from about 5 weight percent to about 45 weight percent of a fixing agent comprising the ester of an acid selected from the group consisting of mono and polybasic carboxylic acids wherein said acids have from 6 to 20 carbon atoms and an alcohol selected from the group consisting of saturated and unsaturated mono and polyhydric aliphatic alcohols having from 2 to 20 carbon atoms.
Claim 2
Dependent Claim 194 words
A chemically stable, nonaqueous, ambipolar, absorptive drying electrostatographic liquid developer of low volatility having a resistivity of from about 10 8 to 10 15 ohm cm comprising from about 30 weight percent to about 85 weight percent of an oleaginous liquid vehicle from about 5 weight percent to about 60 weight percent of a particulate colorant which is insoluble in at least one liquid present in the liquid developer; from about 1 weight percent to about 35 weight percent of a dispersant which is soluble in the oleaginous vehicle and which is capable of substantially supressing background deposits, said dispersant comprising copolymers of alkyl vinyl ethers and maleic anhydride where alkyl substituent of the vinyl ether has a carbon chain length of from 14 to 20 carbon atoms, and from about 5 weight percent to about 45 weight percent of a fixing agent comprising the ester of an acid selected from the group consisting of mono and polybasic carboxylic acids wherein said acids have from 6 to 20 carbon atoms and an alcohol selected from the group consisting of saturated and unsaturated mono and polyhydric aliphatic alcohols having from 2 to 20 carbon atoms.
Claim 3
Dependent Claim 21 words
The liquid developer of claim 1 wherein said colorant comprises a pigment which has previously been predispersed in the resin matrix.
Claim 4
Dependent Claim 14 words
The liquid developer of claim 2 wherein said resin matrix comprises an ester gum.
Claim 5
Dependent Claim 29 words
The liquid developer according to claim 1 wherein said developer has a volatility less than about 0.0050 grams per square centimeter at 60° C. after about 28 days exposure.
Claim 6
Dependent Claim 24 words
The liquid developer according to claim 1 wherein said developer has a viscosity of from about 100 to about 3000 centipoises at 25° C.
Claim 7
Dependent Claim 23 words
The liquid developer according to claim 1 wherein said particulate colorant has a particle size of from about 0.01 to about 10 microns.
Claim 8
Dependent Claim 22 words
The liquid developer according to claim 1 wherein said bulk resistivity is from about 10 10 to about 10 14 ohm cm.
Claim 9
Dependent Claim 15 words
The liquid developer according to claim 1 wherein said oleaginous liquid vehicle comprised mineral oil.
Claim 10
Dependent Claim 15 words
The liquid developer according to claim 1 wherein said fixing agent comprises triethylene glycol dicaprylate.
Claim 11
Dependent Claim 20 words
The liquid developer according to claim 1 wherein said dispersant comprises a copolymer of octadecyl vinyl ether and maleic anhydride.
Claim 12
Dependent Claim 75 words
The liquid developer according to claim 1 wherein said oleaginous vehicle is present in an amount of from about 35 to about 75 weight percent, said colorant is present in an amount of from about 10 to about 35 weight percent, said dispersant is present in an amount of from about 2 to about 25 weight percent, and said fixing agent is present in an amount of from about 110 to about 35 weight percent.

References Cited (Backward Citations)

US3776849A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-04-08 1983-10-08 1984-04-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-04-08 1987-10-08 1988-04-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-04-08 1991-10-08 1992-04-08 $7700.00 Window Closed / Lapsed

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