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US4659640A Expired / Lapsed US ⏱️ 0.0 years remaining

Self-fixing liquid electrographic developers containing polyester toners and dispersed wax and processes for using the same

Assignee: NexPress Solutions LLC
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Filing: 1982-06-21
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Granted: 1987-04-21
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Expires: 2002-06-21
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Abstract

Abstract A novel liquid electrographic developer containing a volatile, electrically insulating carrier liquid, polyester toner particles, and wax dispersed in the carrier is described. The wax-to-polyester weight ratio in the developer is sufficiently high, preferably above 0.25, thereby rendering the developer self-fixing at room temperature. A novel process for developing an electrostatic latent image on a smooth support using a self-fixing liquid developer is also described. Upon application of the developer to a latent image and evaporation of the liquid carrier from the image, the toner, aided by the wax at the indicated concentration level, is fixed to the surface without the need for externally applied heat.

Inventors

  • 👤 Domenic Santilli

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 05:36
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/132; G03G9/135

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 122 words
An electrographic method of forming a self-fixed toner on a support, comprising: (a) establishing a latent electrostatic image on the surface of said support (b) developing said image with a self-fixing, liquid electrographic developer comprising a volatile, electrically insulating liquid carrier and, dispersed in said carrier, (i) toner particles comprising a polyester binder and (ii) wax, to form an unfixed toner image comprising said toner, wax and volatile carrier, and (c) fixing said toner image by allowing said volatile carrier to evaporate from said toner image at room temperature, wherein the concentration of said wax in said developer is sufficient to fix said toner and wax to said surface in the absence of externally applied heat other than that from ambient conditions.
Claim 2
Dependent Claim 122 words
An electrographic method of forming a self-fixed toner on a support, comprising: (a) establishing a latent electrostatic image on the surface of said support (b) developing said image with a self-fixing, liquid electrographic developer comprising a volatile, electrically insulating liquid carrier and, dispersed in said carrier, (i) toner particles comprising a polyester binder and (ii) wax, to form an unfixed toner image comprising said toner, wax and volatile carrier, and (c) fixing said toner image by allowing said volatile carrier to evaporate from said toner image at room temperature, wherein the concentration of said wax in said developer is sufficient to fix said toner and wax to said surface in the absence of externally applied heat other than that from ambient conditions.
Claim 3
Dependent Claim 19 words
The method of claim 1 wherein said wax is a polyolefin wax, a triglyceride wax or a natural wax.
Claim 4
Dependent Claim 27 words
The method of claim 1 wherein said wax comprises a polyethylene wax in a concentration of about 0.125 to 1.0 part by weight wax per part polyester.
Claim 5
Independent Claim 17 words
The method of claims 1, 2 or 3 wherein said volatile liquid carrier is an isoparaffinic hydrocarbon.
Claim 6
Dependent Claim 171 words
An electrographic method of forming a self-fixed image on a support having a smooth, nonporous surface, comprising: (a) establishing a latent electrostatic image on said smooth, nonporous surface, (b) developing said image with a self-fixing, liquid electrographic developer comprising a volatile, electrically insulating, liquid carrier and, dispersed in said carrier, (i) toner particles comprising a polyester binder having one or more aliphatic, alicyclic or aromatic dicarboxylic acid recurring units and recurring diol units of the formula: --O--G.sup.1 --O-- wherein G 1 represents straight- or branched-chain lkylene having about 2 to 12 carbon atoms or cycloalkylene, cycloalkylene-bis(oxyalkylene) or cycloalkylenedialkylene, and (ii) wax incorporated into said toner, to form an unfixed toner image comprising said toner, wax and volatile carrier, and (c) fixing said toner image by allowing said volatile carrier to evaporate from said toner image at room temperature, wherein the concentration of said wax in said developer is sufficient to fix said toner and wax to said surface in the absence of externally applied heat other than that from ambient conditions.
Claim 7
Dependent Claim 171 words
An electrographic method of forming a self-fixed image on a support having a smooth, nonporous surface, comprising: (a) establishing a latent electrostatic image on said smooth, nonporous surface, (b) developing said image with a self-fixing, liquid electrographic developer comprising a volatile, electrically insulating, liquid carrier and, dispersed in said carrier, (i) toner particles comprising a polyester binder having one or more aliphatic, alicyclic or aromatic dicarboxylic acid recurring units and recurring diol units of the formula: --O--G.sup.1 --O-- wherein G 1 represents straight- or branched-chain lkylene having about 2 to 12 carbon atoms or cycloalkylene, cycloalkylene-bis(oxyalkylene) or cycloalkylenedialkylene, and (ii) wax incorporated into said toner, to form an unfixed toner image comprising said toner, wax and volatile carrier, and (c) fixing said toner image by allowing said volatile carrier to evaporate from said toner image at room temperature, wherein the concentration of said wax in said developer is sufficient to fix said toner and wax to said surface in the absence of externally applied heat other than that from ambient conditions.
Claim 8
Dependent Claim 51 words
The method of claim 5 wherein said polyester comprises up to 35 mole percent (based on the total moles of diacid units) of an ionic diacid unit of the structure: ##STR2## wherein: A represents sulfoarylene, sulfoaryloxyarylene, sulfocycloalkylene, arylsulfonylimino, sulfonylarylene, iminobis(sulfonylarylene), sulfoaryloxysulfonylarylene and sulfoaralkylarylene or the alkali metal or ammonium salts thereof.
Claim 9
Independent Claim 27 words
The method of claims 5 or 6 wherein said surface is a smooth, nonporous photoconductive layer comprising a photoconductor and a film-forming polymeric binder for said photoconductor.
Claim 10
Independent Claim 18 words
The method of claims 5 or 6 wherein said surface is a smooth, nonporous, nonphotoconductive dielectric receiving layer.
Claim 11
Independent Claim 14 words
The method of claims 5 or 6 wherein said surface is a film surface.
Claim 12
Independent Claim 21 words
The method of claims 5 or 6 wherein said wax is a polyolefin wax, a triglyceride wax or a natural wax.
Claim 13
Independent Claim 29 words
The method of claims 5 or 6 wherein said wax comprises a polyethylene wax in a concentration of about 0.125 to 1.0 part by weight wax per part polyester.
Claim 14
Independent Claim 16 words
The method of claims 5 or 6 wherein said volatile liquid carrier is an isoparaffinic hydrocarbon.

References Cited (Backward Citations)

US2891911A Cited
US3301698A Cited
GB1035837A Cited
US3850829A Cited
US3954640A Cited
US3985665A Cited
US3997488A Cited
US4052325A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-04-20 1990-10-20 1991-04-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-04-20 1994-10-20 1995-04-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-04-20 1998-10-20 1999-04-21 $7700.00 Window Closed / Lapsed

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