US5047306A
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Humidity tolerant charge director compositions
Assignee: HP Indigo BV
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Filing: 1989-05-19
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Granted: 1991-09-10
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Expires: 2009-05-19
Abstract
Abstract A humidity tolerant charge director composition comprises a fine dispersion in a non-polar solvent of a charge direction material comprising a molecular charge director compound and an ionic charge director compound, each being conjugated to a polymer which is insoluble in non-polar organic solvents. The charge director material is prepared by adding to a solution of a molecular charge director compound and an ionic charge director compound in a non-polar organic solvent, a monomer compound capable of polymerizing to form a polymer which is insoluble in said solvent, initiating a polyerization reaction of the monomer compound and allowing the polmerization reaction to progress to completion.
Inventors
- 👤 Yaacov Almog
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:53
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/135; G03G9/1355; G03G9/13; G03G9/131
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
41 words
A liquid developer including: a non-polar, organic, carrier liquid; pigmented toner particles; and a charge director material comprising a zwitterionic charge director compound and an ionic charge director compound each being conjugated to a polymer which is insoluble in said liquid.
Claim 2
Dependent Claim
41 words
A liquid developer including: a non-polar, organic, carrier liquid; pigmented toner particles; and a charge director material comprising a zwitterionic charge director compound and an ionic charge director compound each being conjugated to a polymer which is insoluble in said liquid.
Claim 3
Dependent Claim
15 words
A liquid developer according to claim 1, wherein the zwitterionic charge director compound is lecithin.
Claim 4
Dependent Claim
17 words
A liquid developer according to claim 1, wherein the ionic charge director compound is basic barium petronate.
Claim 5
Dependent Claim
17 words
A liquid developer according to claim 1, wherein the ionic charge director compound is basic calcium petronate.
Claim 6
Dependent Claim
12 words
A liquid developer according to claim 1, wherein the polymer is polyvinylpyrrolidone.
Claim 7
Dependent Claim
31 words
A liquid developer according to claim 1, wherein the ratio of the zwitterionic charge director compound to the ionic charge director compound is from about 2:1 to about 1:1 by weight.
Claim 8
Dependent Claim
68 words
A process for producing a charge director material which comprises the steps of: dissolving a zwitterionic charge director compound and an ionic charge director compound in a non-polar organic liquid; mixing the solution obtained with a monomer compound capable of polymerising to form a polymer which is insoluble in said liquid; initiating a polymerisation reaction of said monomer compound; and allowing the polymerisation reaction to progress to completion.
Claim 9
Dependent Claim
68 words
A process for producing a charge director material which comprises the steps of: dissolving a zwitterionic charge director compound and an ionic charge director compound in a non-polar organic liquid; mixing the solution obtained with a monomer compound capable of polymerising to form a polymer which is insoluble in said liquid; initiating a polymerisation reaction of said monomer compound; and allowing the polymerisation reaction to progress to completion.
Claim 10
Dependent Claim
14 words
A process according to claim 7, wherein the zwitterionic charge director compound is lecithin.
Claim 11
Dependent Claim
16 words
A process according to claim 7, wherein the ionic charge director compound is basic barium petronate.
Claim 12
Dependent Claim
16 words
A process according to claim 7, wherein the ionic charge director compound is basic calcium petronate.
Claim 13
Dependent Claim
11 words
A process according to claim 7, wherein the monomer is 1-vinyl-2-pyrrolidone.
Claim 14
Dependent Claim
22 words
A process according to claim 7, wherein the non-polar organic liquid is a branched-chain aliphatic hydrocarbon or a mixture of such hydrocarbons.
Claim 15
Dependent Claim
24 words
A process according to claim 7, wherein the non-polar organic liquid is an isoparaffinic hydrocarbon fraction having a boiling range above about 155° C.
Claim 16
Dependent Claim
17 words
A process according to claim 7, wherein the non-polar organic liquid is Isopar H or Isopar L.
Claim 17
Dependent Claim
23 words
A process according to claim 7, wherein the polymerization is carried out at a temperature from about 50° C. to about 90° C.
Claim 18
Dependent Claim
16 words
A process according to claim 7, wherein the polymerization is initiated by the addition of azobisbutyronitrille.
Claim 19
Dependent Claim
32 words
A process according to claim 7, wherein the zwitterionic charge director compound and the ionic charge director compound are used in a ratio of from about 2:1 to about 1:1 by weight.
Claim 20
Dependent Claim
46 words
A charge director composition prepared according to the process of claim 7 and comprising a non-polar organic liquid and, finely dispersed therein, particles of a polymer which is insoluble in said liquid, conjugated with both a zwitterionic charge director compound and an ionic charge director compound.
Claim 21
Dependent Claim
13 words
A charge director composition according to claim 18 wherein the polymer is polyvinylpyrrolidone.
Claim 22
Dependent Claim
16 words
A charge director composition according to claim 18 wherein the zwitterionic charge director compound is lecithin.
Claim 23
Dependent Claim
18 words
A charge director composition according to claim 18 wherein the ionic charge director compound is basic barium petronate.
Claim 24
Dependent Claim
18 words
A charge director composition according to claim 18 wherein the ionic charge director compound is basic calcium petronate.
Claim 25
Dependent Claim
32 words
A charge director composition according to claim 18 wherein the ratio of the zwitterionic charge director compound to the ionic charge director compound is from about 2:1 to about 1:1 by weight.
Claim 26
Dependent Claim
24 words
A charge director composition according to claim 18 wherein the non-polar organic liquid is a branched-chain aliphatic hydrocarbon or a mixture of such hydrocarbons.
Claim 27
Dependent Claim
26 words
A charge director composition according to claim 18 wherein the non-polar organic liquid is an isoparaffinic hydrocarbon fraction having a boiling range above about 155° C.
Claim 28
Dependent Claim
19 words
A charge director composition according to claim 18 wherein the non-polar organic solvent is Isopar H or Isopar L.
Claim 29
Dependent Claim
40 words
For use in electrostatic imaging, a liquid developer system comprising: an insulating non-polar carrier liquid; toner particles dispersed in said carrier liquid; and a charge director material prepared according to the process of claim 7 dispersed in said carrier liquid.
Claim 30
Dependent Claim
51 words
An electrostatic imaging process comprising the steps of: forming a latent electrostatic image on a surface; applying to said surface electrically charged toner particles from a liquid developer system according to claim 27, thereby to form a toner image on said surface; and transferring the resulting toner image to a substrate.
Claim 31
Dependent Claim
70 words
An electrostatic imaging process comprising the steps of: electrostatically charging a photoconductive surface; exposing said photoconductive surface to an optical image thereby forming a latent electrostatic image on said photoconductive surface; applying to said photoconductive surface electrically charged toner particles from a liquid developer system according to claim 27, thereby to form a toner image on said photoconductive surface; and transferring the resulting toner image to a copy sheet substrate.
Claim 32
Dependent Claim
27 words
A method for developing a latent electrostatic image in a liquid-developed electrostatic imaging process, which comprises the use of a liquid developer system according to claim 27.
Claim 33
Dependent Claim
15 words
A liquid-developed electrocopying or electroprinting apparatus comprising a liquid developer system according to claim 27.
Claim 34
Dependent Claim
27 words
A liquid developer according to claim 1 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
Claim 35
Dependent Claim
27 words
A liquid developer according to claim 5 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
Claim 36
Dependent Claim
26 words
A process according to claim 7 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
Claim 37
Dependent Claim
26 words
A process according to claim 11 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
Claim 38
Dependent Claim
28 words
A charge director composition according to claim 18 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
Claim 39
Dependent Claim
28 words
A charge director composition according to claim 19 wherein said zwitterionic charge director compound is lecithin and said ionic charge director compound is barium petronate or calcium petronate.
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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) | 1994-09-09 | 1995-03-11 | 1995-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-09 | 1999-03-11 | 1999-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-09 | 2003-03-11 | 2003-09-10 | $7700.00 | Window Closed / Lapsed |