US4780389A
Expired / Lapsed
US
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Inorganic metal salt as adjuvant for negative liquid electrostatic developers
Assignee: EIDP Inc
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Filing: 1988-02-23
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Granted: 1988-10-25
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Expires: 2008-02-23
Abstract
Abstract Negative, liquid electrostatic developer consisting essentially of (A) nonpolar liquid having Kauri-butanol value less than 30, present in major amount, (B) thermoplastic resin particles having a colorant and an inorganic metal salt as defined dispersed therein and average particle size by area being less than 10 μm, and (C) nonpolar liquid soluble ionic or zwitterionic compound which imparts a negative charge to the thermoplastic resin particles. Optionally additional adjuvants are present. The liquid electrostatic developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
Inventors
- 👤 Lyla M. El-Sayed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:04
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/135; G03G9/1355
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
133 words
A negative, liquid electrostatic developer having improved charging characteristics consisting essentially of (A) a nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount. (B) thermoplastic resin particles having dispersed therein a colorant and an inorganic metal salt, wherein the cation component of said inorganic metal salt is selected from the group consisting of the metals of Group Ia, Group IIa, and group IIIa of the periodic table, and wherein the anion component of said salt is selected from the group consisting of halogen, carbonate, acetate, sulfate, borate, nitrate, and phosphate, the resin particles having an average by area particle size of less than 10 μm, and (C) a nonpolar liquid soluble ionic or zwitterionic charge director compound which imparts a negative charge to the thermoplastic resin particles.
Claim 2
Dependent Claim
133 words
A negative, liquid electrostatic developer having improved charging characteristics consisting essentially of (A) a nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount. (B) thermoplastic resin particles having dispersed therein a colorant and an inorganic metal salt, wherein the cation component of said inorganic metal salt is selected from the group consisting of the metals of Group Ia, Group IIa, and group IIIa of the periodic table, and wherein the anion component of said salt is selected from the group consisting of halogen, carbonate, acetate, sulfate, borate, nitrate, and phosphate, the resin particles having an average by area particle size of less than 10 μm, and (C) a nonpolar liquid soluble ionic or zwitterionic charge director compound which imparts a negative charge to the thermoplastic resin particles.
Claim 3
Dependent Claim
34 words
A negative liquid electrostatic developer according to claim 1 wherein the cationic component is a metal selected from the group consisting of sodium, potassium, barium, calcium, magnesium, strontium, aluminum, lithium, rubidium, cesium, and beryllium.
Claim 4
Dependent Claim
51 words
A negative liquid electrostatic developer according to claim 2 wherein the inorganic metal salt is a compound selected from the group consisting of sodium chloride, sodium bromide, sodium calcium carbonate, cesium chloride, rubidium nitrate, beryllium sulfate, lithium bromide, rubidium acetate, strontium chloride, calcium acetate, aluminum sulfate, sodium borate, and sodium phosphate.
Claim 5
Dependent Claim
55 words
A negative, liquid electrostatic developer according to claim 1 wherein component (A) is present in 85 to 99.9% by weight, based on the total weight of liquid developer, the total weight of developer solids is 0.1 to 15.0% by weight, and component (C) is present in an amount of 0.25 to 1500 mg/g developer solids.
Claim 6
Dependent Claim
32 words
A negative, liquid electrostatic developer according to claim 4 wherein the inorganic metal salt is present in 0.01 to 60 percent by weight based on the total weight of the developer solids.
Claim 7
Dependent Claim
28 words
A negative, liquid electrostatic developer according to claim 1 containing up to about 60 percent by weight of a colorant based on the total weight of developer solids.
Claim 8
Dependent Claim
15 words
A negative, liquid electrostatic developer according to claim 6 wherein the colorant is a pigment.
Claim 9
Dependent Claim
15 words
A negative, liquid electrostatic developer according to claim 6 wherein the colorant is a dye.
Claim 10
Dependent Claim
17 words
A negative, liquid electrostatic developer according to claim 1 wherein a fine particle size oxide is present.
Claim 11
Dependent Claim
36 words
A negative, liquid electrostatic developer according to claim 1 wherein an additional compound is present which is an adjuvant selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon.
Claim 12
Dependent Claim
36 words
A negative, liquid electrostatic developer according to claim 6 wherein an additional compound is present which is an adjuvant selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon.
Claim 13
Dependent Claim
16 words
A negative, liquid electrostatic developer according to claim 10 wherein a polyhydroxy adjuvant compound is present.
Claim 14
Dependent Claim
16 words
A negative, liquid electrostatic developer according to claim 10 wherein an aminoalcohol adjuvant compound is present.
Claim 15
Dependent Claim
17 words
A negative, liquid electrostatic developer according to claim 10 wherein a polybutylene succinimide adjuvant compound is present.
Claim 16
Dependent Claim
17 words
A negative, liquid electrostatic developer according to claim 10 wherein a metallic soap adjuvant compound is present.
Claim 17
Dependent Claim
17 words
A negative, liquid electrostatic developer according to claim 10 wherein an aromatic hydrocarbon adjuvant compound is present.
Claim 18
Dependent Claim
16 words
A negative, liquid electrostatic developer according to claim 13 wherein the aminoalcohol adjuvant compound is triisopropanolamine.
Claim 19
Dependent Claim
34 words
A negative, liquid electrostatic developer 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 20
Dependent Claim
15 words
A negative, liquid electrostatic developer according to claim 1 wherein the thermoplastic resin is polystyrene.
Claim 21
Dependent Claim
43 words
A negative, liquid electrostatic developer according to claim 1 wherein the thermoplastic resin is 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 22
Dependent Claim
44 words
A negative, liquid electrostatic developer according to claim 6 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 23
Dependent Claim
30 words
A negative, liquid electrostatic developer according to claim 20 wherein the thermoplastic resin is a copolymer of ethylene (89%)/methacrylic acid (11%) having a melt index at 190° C. of 100.
Claim 24
Dependent Claim
24 words
A negative, liquid electrostatic developer according to claim 1 wherein the particles have an average by area particle size of less than 5 μm.
Claim 25
Dependent Claim
16 words
A negative, liquid electrostatic toner according to claim 1 wherein component (C) is Basic Barium Petronate.
Claim 26
Dependent Claim
14 words
A negative, liquid electrostatic toner according to claim 1 wherein component (C) is lecithin.
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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) | 1991-10-25 | 1992-04-25 | 1992-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-25 | 1996-04-25 | 1996-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-25 | 2000-04-25 | 2000-10-25 | $7700.00 | Window Closed / Lapsed |