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US4783389A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparation of liquid electrostatic developers

Assignee: EIDP Inc
•
Filing: 1987-03-27
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Granted: 1988-11-08
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Expires: 2007-03-27
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Abstract

Abstract Process for the preparation of toner particles for liquid electrostatic imaging comprising (A) mixing a thermoplastic resin and a nonpolar liquid at a temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid boils and the resin decomposes, (B) cooling the mixture to form resin particles in the nonpolar liquid, (C) reducing the size of the resin particles to below about 30 μm by passing the product of step (B) through at least one liquid jet interaction chamber at a liquid pressure of at least 1000 p.s.i., e.g., a Microfluidizer®. The process produces liquid electrostatic developer quicker than other known processes, the developer being useful in copying, making proofs, including digital proofs, etc.

Inventors

  • 👤 Torence J. Trout
  • 👤 James R. Larson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 12:14
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12

Claims Analysis

Total Claims: 37
Claim 1
Independent Claim 104 words
A process for the preparation of toner particles for liquid electrostatic imaging comprising A. mixing a thermoplastic resin and a nonpolar liquid at a temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid boils and the resin decomposes; B. cooling the mixture to form particles of the resin in the nonpolar liquid; C. reducing the size of the resin particles to below about 30 μm by passing the mixture of resin particles and nonpolar liquid through at least a plurality of nozzles within a liquid jet interaction chamber at a liquid pressure of at least 1000 p.s.i.
Claim 2
Dependent Claim 104 words
A process for the preparation of toner particles for liquid electrostatic imaging comprising A. mixing a thermoplastic resin and a nonpolar liquid at a temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid boils and the resin decomposes; B. cooling the mixture to form particles of the resin in the nonpolar liquid; C. reducing the size of the resin particles to below about 30 μm by passing the mixture of resin particles and nonpolar liquid through at least a plurality of nozzles within a liquid jet interaction chamber at a liquid pressure of at least 1000 p.s.i.
Claim 3
Dependent Claim 23 words
A process according to claim 1 wherein the mixing in step A is conducted in a vessel by means of moving particulate media.
Claim 4
Dependent Claim 27 words
A process according to claim 2 wherein the particulate media are taken from the group consisting of stainless steel, carbon steel, ceramic, alumina, zirconium, silica, and sillimanite.
Claim 5
Dependent Claim 21 words
A process according to claim 3 wherein the particulate media are spherical having an average diameter of 0.04 to 0.5 inch.
Claim 6
Dependent Claim 19 words
A process according to claim 1 wherein the mixing in step A is conducted in a vessel by stirring.
Claim 7
Dependent Claim 29 words
A process according to claim 1 wherein the mixing in step A is conducted in a liquid jet interaction chamber at a liquid pressure of at least 1000 p.s.i.
Claim 8
Dependent Claim 171 words
A process according to claim 1 wherein the liquid jet interaction chamber comprises, in combination, (a) a plurality of submerged nozzles providing elongated orifices arranged to eject under pressure a plurality of thin sheets of the mixture of thermoplastic resin and nonpolar liquid, the nozzles being arranged to effect turbulent jet action of the sheets along a common liquid jet interaction front and the sheets being ejected by the nozzles into a low pressure zone filled with the liquid further creating turbulent jet interaction along a common boundary essentially defined and formed by the mixture in the low pressure zone and by the sheets ejected into the low pressure zone; (b) jet interaction chamber-defining means arranged to provide the low pressure zone of the liquid system in which the turbulent jet interaction is effected; (c) inlet channel means to deliver the mixture under pressure to the nozzles; and (d) means to withdraw the mixture of resin particles and nonpolar liquid in the form of a dispersion from the low pressure zone.
Claim 9
Dependent Claim 171 words
A process according to claim 6 wherein the liquid jet interaction chamber comprises, in combination, (a) a plurality of submerged nozzles providing elongated orifices arranged to eject under pressure a plurality of thin sheets of the mixture of thermoplastic resin and nonpolar liquid, the nozzles being arranged to effect turbulent jet action of the sheets along a common liquid jet interaction front and the sheets being ejected by the nozzles into a low pressure zone filled with the liquid further creating turbulent jet interaction along a common boundary essentially defined and formed by the mixture in the low pressure zone and by the sheets ejected into the low pressure zone; (b) jet interaction chamber-defining means arranged to provide the low pressure zone of the liquid system in which the turbulent jet interaction is effected; (c) inlet channel means to deliver the mixture under pressure to the nozzles; and (d) means to withdraw the mixture of resin particles and nonpolar liquid in the form of a dispersion from the low pressure zone.
Claim 10
Dependent Claim 31 words
A process according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene and an α-β-ethylenically unsaturated acid selected from the group consisting of acrylic acid and methacrylic acid.
Claim 11
Dependent Claim 12 words
A process according to claim 1 wherein the thermoplastic resin is polyethylene.
Claim 12
Dependent Claim 41 words
A process according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 to 0%)/alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 5 carbon atoms (0 to 20%).
Claim 13
Dependent Claim 27 words
A process according to claim 11 wherein the thermoplastic resin is a copolymer of ethylene (89%)/methacrylic acid (11%) having a melt index at 190° C. of 100.
Claim 14
Dependent Claim 12 words
A process according to claim 1 wherein the thermoplastic resin is polystyrene.
Claim 15
Dependent Claim 30 words
A process according to claim 1 wherein a colorant is present in step A in an amount up to 60% by weight based on the total weight of developer solids.
Claim 16
Dependent Claim 12 words
A process according to claim 14 wherein the colorant is a pigment.
Claim 17
Dependent Claim 12 words
A process according to claim 14 wherein the colorant is a dye.
Claim 18
Dependent Claim 20 words
A process according to claim 1 wherein a colorant is present which is a pigment comprising finely divided ferromagnetic material
Claim 19
Dependent Claim 13 words
A process according to claim 14 wherein the colorant is a metal powder.
Claim 20
Dependent Claim 14 words
A process according to claim 1 wherein a fine particle size oxide is present.
Claim 21
Dependent Claim 11 words
A process according to claim 19 wherein the oxide is silica.
Claim 22
Dependent Claim 36 words
A process according to claim 1 wherein after step C a charge director in an amount of 1 to 1000 mg/g solids is added to impart an electrostatic charge of predetermined polarity to the resin particles.
Claim 23
Dependent Claim 12 words
A process according to claim 21 wherein the charge director is lecithin.
Claim 24
Dependent Claim 14 words
A process according to claim 21 wherein the charge director is Basic Barium Petronate.
Claim 25
Dependent Claim 28 words
A process acoording to claim 21 wherein the thermoplastic resin is a copolymer of ethylene and methacrylic acid (11%) having a melt index at 190° C. of 100.
Claim 26
Dependent Claim 17 words
A process according to claim 1 wherein the thermoplastic resin particles have dispersed therein a metallic soap.
Claim 27
Dependent Claim 13 words
A process according to claim 25 wherein the metallic soap is aluminum tristearate.
Claim 28
Dependent Claim 25 words
A process according to claim 25 wherein the metallic soap is present in 0.01 to 60% by weight based on the total weight of solids.
Claim 29
Dependent Claim 18 words
A process according to claim 1 wherein subsequent to step C diluting the mixture with additional nonpolar liquid.
Claim 30
Dependent Claim 29 words
A process according to claim 28 wherein the thermoplastic resin is a copolymer of ethylene (89%) and methacrylic acid (11%) having a melt index at 190° C. of 100.
Claim 31
Dependent Claim 32 words
A process according to claim 28 wherein the dilution is conducted to reduce the concentration of toner particles to between 0.1 to 3.0 percent by weight with respect to the nonpolar liquid.
Claim 32
Dependent Claim 20 words
A process according to claim 1 wherein the toner particles have an average particle size of less than 15 μm.
Claim 33
Dependent Claim 31 words
A process according to claim 1 wherein an additional compound is present which is an adjuvant taken from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide and an aromatic hydrocarbon.
Claim 34
Dependent Claim 13 words
A process according to claim 32 wherein the adjuvant is a polyhydroxy compound.
Claim 35
Dependent Claim 12 words
A process according to claim 32 wherein the adjuvant is an aminoalcohol.
Claim 36
Dependent Claim 12 words
A process according to claim 32 wherein the adjuvant is polybutylene succinimide.
Claim 37
Dependent Claim 13 words
A process according to claim 32 wherein the adjuvant is an aromatic hydrocarbon.

References Cited (Backward Citations)

US3514043A Cited
US3944493A Cited
US4345013A Cited
US4533254A Cited
US4599294A Cited
GB2169416A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-11-08 1992-05-09 1992-11-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-11-08 1996-05-09 1996-11-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-11-08 2000-05-09 2000-11-08 $7700.00 Window Closed / Lapsed

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