Patent US4789616A successfully refreshed from Google Patents.
US4789616A
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US
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Processes for liquid developer compositions with high transfer efficiencies
Assignee: Xerox Corp
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Filing: 1987-11-09
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Granted: 1988-12-06
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Expires: 2007-11-09
Abstract
Abstract A process for the preparation of liquid developer compositions containing dyed polymer particles with an average diameter of from about 2 to about 6 microns, which particles are dispersed in an oil base, charge control additives, and stabilizers thereby permitting image transfer efficiencies exceeding 80 percent, which comprises formulating polymer particles by dispersion polymerization in a mixture comprised of a first oil base solvent, and a second solvent with a higher volatility than said first solvent, and further containing an amphipathic steric stabilizer; thereafter dyeing the product resulting; followed by removal of the more volatile second solvent; and subsequently adding to the dyed product a charge control additive.
Inventors
- 👤 Melvin D. Croucher
- 👤 Raymond W. Wong
- 👤 Christopher K. Ober
- 👤 Michael L. Hair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:34
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
112 words
A process for the preparation of liquid developer compositions containing dyed polymer particles with an average diameter of from about 2 to about 6 microns, which particles are dispersed in an oil base, charge control additives, and stabilizers thereby permitting image transfer efficiencies exceeding 80 percent, which comprises formulating polymer particles by dispersion polymerization in a mixture comprised of a first oil base solvent having an amphipathic steric stabilizer dissolved therein and a second solvent with a higher volatility than said first solvent having monomer(s) dissolved therein; thereafter dyeing the product resulting; followed by removal of the more volatile second solvent; and subsequently adding to the dyed product a charge control additive.
Claim 2
Dependent Claim
112 words
A process for the preparation of liquid developer compositions containing dyed polymer particles with an average diameter of from about 2 to about 6 microns, which particles are dispersed in an oil base, charge control additives, and stabilizers thereby permitting image transfer efficiencies exceeding 80 percent, which comprises formulating polymer particles by dispersion polymerization in a mixture comprised of a first oil base solvent having an amphipathic steric stabilizer dissolved therein and a second solvent with a higher volatility than said first solvent having monomer(s) dissolved therein; thereafter dyeing the product resulting; followed by removal of the more volatile second solvent; and subsequently adding to the dyed product a charge control additive.
Claim 3
Dependent Claim
23 words
A process in accordance with claim 1 wherein the first solvent is selected from Isopars®, and the second solvent is an aromatic hydrocarbon.
Claim 4
Dependent Claim
25 words
A process in accordance with claim 1 wherein the first oil base solvent is selected from the group consisting of Isopar® H, G and L.
Claim 5
Dependent Claim
22 words
A process in accordance with claim 1 wherein the dye is selected from the group consisting of red, blue, and yellow components.
Claim 6
Dependent Claim
24 words
A process in accordance with claim 1 wherein the dye is selected from the group consisting of cyan, magenta, and yellow; and mixtures thereof.
Claim 7
Dependent Claim
25 words
A process in accordance with claim 1 wherein the polymer particles are selected from the group consisting of poly(methyl methacrylate), poly(ethyl acrylate), and copolymers thereof.
Claim 8
Dependent Claim
25 words
A process in accordance with claim 1 wherein the charge control additive is selected from the group consisting of Lecithin, polyisobutylene succinimide, and zirconium octoate.
Claim 9
Dependent Claim
24 words
A process in accordance with claim 1 wherein the stabilizer is selected from the group consisting of poly(isobutylene-co-isoprene), poly(2-ethyl hexyl methacrylate), and poly(styrene-b-hydrogenated butadiene).
Claim 10
Dependent Claim
23 words
A process in accordance with claim 1 wherein the transfer efficiency of the resulting ink is from 80 percent to about 99 percent.
Claim 11
Dependent Claim
24 words
A process in accordance with claim 6 wherein the dye is selected from the group consisting of cyan, magenta, and yellow; and mixtures thereof.
Claim 12
Dependent Claim
68 words
A process in accordance with claim 1 wherein the liquid developer composition resulting contains from about 90 percent to about 99.5 percent by weight of the first oil base solvent, from about 0.5 percent to about 6 percent by weight of dye particles, from about 0.01 to about 2 percent by weight of charge control additive, and from about 0.5 to about 4 percent by weight of stablizer.
Claim 13
Dependent Claim
17 words
A process in accordance with claim 1 wherein the more volatile second solvent is removed by heating.
Claim 14
Dependent Claim
13 words
A process in accordance with claim 1 wherein the second solvent is xylene.
Claim 15
Dependent Claim
13 words
A process in accordance with claim 1 wherein the second solvent is toluene.
Claim 16
Dependent Claim
43 words
A process in accordance with claim 1 wherein the first solvent is present in an amount of from about 85 to about 50 weight percent, and the second solvent is present in an amount of from about 20 to about 40 weight percent.
Claim 17
Dependent Claim
43 words
A process in accordance with claim 1 wherein the first solvent is present in an amount of from about 80 to about 60 weight percent, and the second solvent is present in an amount of from about 20 to about 40 weight percent.
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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) | 1991-12-06 | 1992-06-06 | 1992-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-06 | 1996-06-06 | 1996-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-06 | 2000-06-06 | 2000-12-06 | $7700.00 | Window Closed / Lapsed |