US5053306A
Expired / Lapsed
US
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Acid-containing a-b block copolymers as grinding aids in liquid electrostatic developer preparation
Assignee: Dx Imaging Inc
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Filing: 1990-03-07
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Granted: 1991-10-01
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Expires: 2010-03-07
Abstract
Abstract Process for the preparation of toner particles for electrostatic liquid developers comprising (A) dispersing at ambient temperature colorant, A-B diblock polymer grinding aid as described, and a carrier liquid; (B) adding to the dispersion a thermoplastic resin and dispersing at an elevated temperature to plasticize and liquify the resin; (C) cooling the dispersion as described while grinding with particulate media, (D) separating the dispersion of toner particles average by area particle size less than 10 μm, from the particulate media, and (E) adding during or subsequent to step (B) at least one ionic or zwitterionic charge director compound. Steps (A) and (B) can be combined by adding the thermoplastic resin to the other ingredients and dispersing at an elevated temperature. The liquid developer can be prepared omore quickly by the process than by other known processes. The liquid developers are useful in copying, in making color proofs, etc.
Inventors
- 👤 Lyla M. El-Sayed
- 👤 Loretta A. G. Page
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:54
CPC Classifications
G; G03; G03G; G03G15/00; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/133
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
200 words
A process for preparing liquid electrostatic developers for electrostatic imaging comprising: (A) dispersing at ambient temperature in a vessel, a colorant, a nonpolar liquid having a Kauri-butanol value of less than 30 and an A-B diblock polymer wherein the A block is a carboxylic acid-containing polymer, the B block is a polymer or copolymer which is soluble in the nonpolar liquid; (B) adding to the dispersion a thermoplastic resin and dispersing at an elevated temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid degrades and the resin and/or colorant decomposes; (C) cooling the dispersion, either (1) without stirring to form a gel or solid mass and grinding by means of particulate media; (2) with stirring to form a viscous mixture and grinding by means of particulate media; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass; (D) separating the dispersion of toner particles having an average by area particle size of less than 10 μm from the particulate media, and (E) adding to the dispersion during or subsequent to Step (B) at least one nonpolar liquid soluble ionic or zwitterionic charge director compound.
Claim 2
Dependent Claim
200 words
A process for preparing liquid electrostatic developers for electrostatic imaging comprising: (A) dispersing at ambient temperature in a vessel, a colorant, a nonpolar liquid having a Kauri-butanol value of less than 30 and an A-B diblock polymer wherein the A block is a carboxylic acid-containing polymer, the B block is a polymer or copolymer which is soluble in the nonpolar liquid; (B) adding to the dispersion a thermoplastic resin and dispersing at an elevated temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid degrades and the resin and/or colorant decomposes; (C) cooling the dispersion, either (1) without stirring to form a gel or solid mass and grinding by means of particulate media; (2) with stirring to form a viscous mixture and grinding by means of particulate media; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass; (D) separating the dispersion of toner particles having an average by area particle size of less than 10 μm from the particulate media, and (E) adding to the dispersion during or subsequent to Step (B) at least one nonpolar liquid soluble ionic or zwitterionic charge director compound.
Claim 3
Dependent Claim
40 words
A process according to claim 1 wherein the A block of the A-B diblock polymer is a polymer prepared from a monomer selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, alkylaryl and substituted alkylaryl carboxylic acid.
Claim 4
Dependent Claim
57 words
A process according to claim 1 wherein the B block of the A-B diblock polymer is a polymer prepared from at least one monomer selected from the group consisting of butadiene, isoprene and compounds of the general formulas: CH.sub. 2═CCH.sub. 3CO.sub. 2R and CH.sub. 250 CHCO.sub. 2R wherein R is alkyl of 8 to 30 carbon atoms.
Claim 5
Dependent Claim
50 words
A process according to claim 1 wherein the A-B diblock polymer is selected from the group consisting of polymethacrylic acid and polyethylhexyl methacrylate, poly(4-vinyl benzoic acid) and polybutadiene; polyacrylic acid and polylauryl methacrylate; polymethacrylic acid and ethylhexyl acrylate; poly(2-vinyl benzoic acid) and polyisoprene; and poly(3-vinyl benzoic acid) and polystearyl methacrylate.
Claim 6
Dependent Claim
25 words
A process according to claim 1 wherein the A-B diblock polymer is present in an amount of 5 to 40% by weight of developer solids.
Claim 7
Dependent Claim
31 words
A process according to claim 1 wherein the A block is present in an amount of 5 to 40% by weight based on the total weight of the A-B diblock polymer.
Claim 8
Dependent Claim
29 words
A process according to claim 1 wherein the A-B diblock polymer is polymethacrylic acid wherein degree of polymerization is 8 and poly(2-ethylhexyl) methacrylate wherein degree of polymerization is 40.
Claim 9
Dependent Claim
29 words
A process according to claim 1 wherein the A-B diblock polymer is polymethacrylic acid wherein degree of polymerization is 8 and poly(2-ethylhexyl) methacrylate wherein degree of polymerization is 20.
Claim 10
Dependent Claim
41 words
A process according to claim 1 wherein there is present in the vessel up to 100% by weight of a polar liquid having a Kauri-butanol value of at least 30, the percentage based on the total weight of the developer liquid.
Claim 11
Dependent Claim
27 words
A process according to claim 1 wherein the particulate media are selected from the group consisting of stainless steel, carbon steel, ceramic, alumina, zirconia, silica and sillimanite.
Claim 12
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 13
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 14
Dependent Claim
25 words
A process according to claim 12 wherein the thermoplastic resin is a copolymer of ethylene (89%)/methacrylic acid (11%) having a melt index at 190° C.
Claim 15
Dependent Claim
38 words
A process according to claim 1 wherein the thermoplastic resin component is a copolymer of acrylic or methacrylic acid and at least one alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 20 carbon atoms.
Claim 16
Dependent Claim
22 words
A process according to claim 14 wherein the thermoplastic resin component is a copolymer of methyl methacrylate (50-90%)/methacrylic acid (0-20%)/ethylhexyl acrylate (10-50%).
Claim 17
Dependent Claim
38 words
A process according to claim 1 wherein additional nonpolar liquid, polar liquid, or combinations thereof is present to reduce the concentration of toner particles to between 0.1 to 15 percent by weight with respect to the developer liquid.
Claim 18
Dependent Claim
18 words
A process according to claim 16 wherein the concentration of toner particles is reduced by additional nonpolar liquid.
Claim 19
Dependent Claim
37 words
A process according to claim 1 wherein cooling the dispersion is accomplished while grinding by means of particulate media to prevent the formation of a gel or solid mass with or without the presence of additional liquid.
Claim 20
Dependent Claim
44 words
A process according to claim 1 wherein cooling the dispersion is accomplished without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding by means of particulate media with or without the presence of additional liquid.
Claim 21
Dependent Claim
34 words
A process according to claim 1 wherein cooling the dispersion is accomplished with stirring to form a viscous mixture and grinding by means of particulate media with or without the presence of additional liquid.
Claim 22
Dependent Claim
37 words
A process according to claim 1 wherein an adjuvant compound selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon is added during the dispersing step (B) or subsequent thereto.
Claim 23
Dependent Claim
13 words
A process according to claim 21 wherein the adjuvant compound is an aminoalcohol.
Claim 24
Dependent Claim
29 words
A process according to claim 16 wherein an adjuvant compound selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon is added.
Claim 25
Dependent Claim
14 words
A process according to claim 23 wherein the adjuvant compound is a polyhydroxy compound.
Claim 26
Dependent Claim
19 words
A process according to claim 23 wherein the adjuvant compound is a metallic soap dispersed in the thermoplastic resin.
Claim 27
Dependent Claim
16 words
A process according to claim 25 wherein the metallic soap adjuvant compound is an aluminium stearate.
Claim 28
Dependent Claim
28 words
A process according to claim 1 wherein the colorant is present in an amount up to about 60% by weight based on the total weight of developer solids.
Claim 29
Dependent Claim
12 words
A process according to claim 27 wherein the colorant is a pigment.
Claim 30
Dependent Claim
19 words
A process according to claim 1 wherein the colorant is added after homogenizing the thermoplastic resin and nonpolar liquid.
Claim 31
Dependent Claim
13 words
A process according to claim 1 wherein the charge director compound is lecithin.
Claim 32
Dependent Claim
16 words
A process according to claim 1 wherein the charge director compound is an oil-soluble petroleum sulfonate.
Claim 33
Dependent Claim
15 words
A process according to claim 1 wherein the charge director compound is an anionic glyceride.
Claim 34
Dependent Claim
21 words
A process according to claim 1 wherein the developer particles have an average particle size of about 1 μm or less.
Claim 35
Dependent Claim
200 words
A process for preparing liquid electrostatic developers for electrostatic imaging comprising: (A) dispersing at an elevated temperature in a vessel a thermoplastic resin, a colorant, a nonpolar liquid having a Kauri-butanol value of less than 30 and an A-B diblock polymer wherein the A block is a carboxylic acid-containing polymer, the B block is a polymer or copolymer which is soluble in the nonpolar liquid, while maintaining the temperature in the vessel at a temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid degrades and the resin and/or colorant decomposes; (B) cooling the dispersion, either (1) without stirring to form a gel or solid mass and grinding by means of particulate media; (2) with stirring to form a viscous mixture and grinding by means of particulate media; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass; (C) separating the dispersion of toner particles having an average by area particle size of less than 10 μm from the particulate media, and (D) adding to the dispersion during or subsequent to Step (A) at least one nonpolar liquid soluble ionic or zwitterionic charge director compound.
Claim 36
Dependent Claim
200 words
A process for preparing liquid electrostatic developers for electrostatic imaging comprising: (A) dispersing at an elevated temperature in a vessel a thermoplastic resin, a colorant, a nonpolar liquid having a Kauri-butanol value of less than 30 and an A-B diblock polymer wherein the A block is a carboxylic acid-containing polymer, the B block is a polymer or copolymer which is soluble in the nonpolar liquid, while maintaining the temperature in the vessel at a temperature sufficient to plasticize and liquify the resin and below that at which the nonpolar liquid degrades and the resin and/or colorant decomposes; (B) cooling the dispersion, either (1) without stirring to form a gel or solid mass and grinding by means of particulate media; (2) with stirring to form a viscous mixture and grinding by means of particulate media; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass; (C) separating the dispersion of toner particles having an average by area particle size of less than 10 μm from the particulate media, and (D) adding to the dispersion during or subsequent to Step (A) at least one nonpolar liquid soluble ionic or zwitterionic charge director compound.
Claim 37
Dependent Claim
40 words
A process according to claim 34 wherein the A block of the A-B diblock polymer is a polymer prepared from a monomer selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, alkylaryl and substituted alkylaryl carboxylic acid.
Claim 38
Dependent Claim
56 words
A process according to claim 34 wherein the B block of the A-B diblock polymer is a polymer prepared from at least one monomer selected from the group consisting of butadiene, isoprene and compounds of the general formulas: CH.sub. 2═CCH.sub. 3CO.sub. 2R and CH.sub. 2═CHCO.sub. 2R wherein R is alkyl of 8 to 30 carbon atoms.
Claim 39
Dependent Claim
50 words
A process according to claim 34 wherein the A-B diblock polymer is selected from the group consisting of polymethacrylic acid and polyethylhexyl methacrylate, poly(4-vinyl benzoic acid) and polybutadiene; polyacrylic acid and polylauryl methacrylate; polymethacrylic acid and ethylhexyl acrylate; poly(2-vinyl benzoic acid) and polyisoprene; and poly(3-vinyl benzoic acid) and polystearyl methacrylate.
Claim 40
Dependent Claim
25 words
A process according to claim 34 wherein the A-B diblock polymer is present in an amount of 5 to 40% by weight of developer solids.
Claim 41
Dependent Claim
31 words
A process according to claim 34 wherein the A block is present in an amount of 5 to 40% by weight based on the total weight of the A-B diblock polymer.
Claim 42
Dependent Claim
29 words
A process according to claim 34 wherein the A-B diblock polymer is polymethacrylic acid wherein degree of polymerization is 8 and poly(2-ethylhexyl) methacrylate wherein degree of polymerization is 40.
Claim 43
Dependent Claim
29 words
A process according to claim 34 wherein the A-B diblock polymer is polymethacrylic acid wherein degree of polymerization is 8 and poly(2-ethylhexyl) methacrylate wherein degree of polymerization is 20.
Claim 44
Dependent Claim
41 words
A process according to claim 34 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%).
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-30 | 1995-04-01 | 1995-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-30 | 1999-04-01 | 1999-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-30 | 2003-04-01 | 2003-10-01 | $7700.00 | Window Closed / Lapsed |