US4062789A
Expired / Lapsed
US
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Liquid developer for electrophotography
Assignee: Fujifilm Holdings Corp
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Filing: 1974-05-01
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Granted: 1977-12-13
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Expires: 1994-05-01
Abstract
Abstract A liquid developer for electrophotography is disclosed which comprises toner particles, a regulating agent composed of a copolymer of a half-alkylamide of maleic acid and α-diisobutylene and an electric insulating carrier liquid and, if desired, an organic acid.
Inventors
- 👤 Tasuo Tamai
- 👤 Sadao Osawa
- 👤 Hajime Miyatuka
- 👤 Masaya Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:18
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/125; G03G9/13; G03G9/131; G03G9/135; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/105
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
159 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ω cm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil, 2. from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid of a copolymer of a half alkylamide of maleic acid and diisobutylene, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain, and 3. from about 0.05 to about 50 parts by f weight per 1000 parts by weight of said carrier liquid of positively charged toner particles having an average particle size of less than about 5 microns.
Claim 2
Dependent Claim
159 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ω cm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil, 2. from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid of a copolymer of a half alkylamide of maleic acid and diisobutylene, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain, and 3. from about 0.05 to about 50 parts by f weight per 1000 parts by weight of said carrier liquid of positively charged toner particles having an average particle size of less than about 5 microns.
Claim 3
Dependent Claim
33 words
The liquid developer as claimed in claim 1 wherein said developer further contains up to about 20 parts by weight of an organic acid per 1000 parts by weight of said carrier liquid.
Claim 4
Dependent Claim
29 words
The liquid developer as claimed in claim 2, wherein said organic aid is an aromatic acid, a chlorinated fatty acid, a saturated fatty acid, or an unsaturated fatty acid.
Claim 5
Dependent Claim
51 words
The liquid developer as claimed in claim 3, wherein said organic acid is benzoic acid, succinic acid, monochloroacetic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, capric acid, lauric acid,myristic acid, palmitic acid, stearic acid, behenic acid, cerotic acid, oleic acid, sorbic acid, linoleic acid, or linolenic acid.
Claim 6
Dependent Claim
45 words
The liquid developer as claimed in claim 1, wherein said developer additionally contains a resin soluble in said carrier liquid, said resin being present in an amount of from about 0.5 to 100 parts by weight per 1000 parts by weight of said carrier liquid.
Claim 7
Dependent Claim
32 words
The liquid developer as claimed in claim 5 wherein said resin soluble in said carrier liquid is an alkyd resin, a rosin-modified phenolformaldehyde resin, polystyrene, an acrylic resin, or a polyisobutylene resin.
Claim 8
Dependent Claim
28 words
The liquid developer as claimed in claim 1, wherein said alkyl group of said half alkylamide of maleic acid contains from about 6 to about 24 carbon atoms.
Claim 9
Dependent Claim
52 words
The liquid developer as claimed in claim 7 wherein said alkyl group of said half alkylamide of maleic acid contains less than about 12 carbon atoms and wherein said developer further contains up to about 20 parts by weight of an organic acid per 1000 parts by weight of said carrier liquid.
Claim 10
Dependent Claim
23 words
The liquid developer as claimed in claim 1 wherein said toner particles have an average particle size of less than about 2 microns.
Claim 11
Dependent Claim
22 words
The liquid developer as claimed in claim 1 wherein said toner particles are carbon black, phthalocyanine blue, quinacridone magenta, or benzidine yellow.
Claim 12
Dependent Claim
43 words
The liquid developer as claimed in claim 1, wherein said copolymer of said half alkylamide of maleic acid and diisobutylene is present at a level from about 0.005 to about 0.2 parts by weight per 1000 parts by weight of said carrier liquid.
Claim 13
Dependent Claim
15 words
The liquid develoer of claim 1 wherein said carrier liquid is an isoparaffinic hydrocarbon solvent.
Claim 14
Dependent Claim
119 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ωcm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil. 2. positively charged toner pigment particles insoluble in said carrier liquid at a level of from about 0.5 to about 50 parts by weight per 1000 parts by weight of said carrier liquid, 3. a resin soluble in said carrier liquid, said resin being present in said carrier liquid in an amount of from about 0.5 to about 100 parts by weight per 1000 parts by weight of said carrier liquid, and
Claim 15
Dependent Claim
119 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ωcm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil. 2. positively charged toner pigment particles insoluble in said carrier liquid at a level of from about 0.5 to about 50 parts by weight per 1000 parts by weight of said carrier liquid, 3. a resin soluble in said carrier liquid, said resin being present in said carrier liquid in an amount of from about 0.5 to about 100 parts by weight per 1000 parts by weight of said carrier liquid, and
Claim 16
Dependent Claim
74 words
a copolymer of half-alkylamide of maleic acid and diisobutylene at a level of from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain.
Claim 17
Dependent Claim
74 words
a copolymer of half-alkylamide of maleic acid and diisobutylene at a level of from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain.
Claim 18
Dependent Claim
34 words
The liquid developer as claimed in claim 13 wherein said liquid developer additionally contains up to about 20 parts by weight of an organic acid per 1000 parts by weight of said carrier liquid.
Claim 19
Dependent Claim
14 words
The liquid developer of claim 13 wherein said carrier liquid is an isoparaffinic hydrocarbon.
Claim 20
Dependent Claim
109 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ωcm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil, 2. from about 0.5 to about 50 parts by weight per 1000 parts by weight of said carrier liquid of positively charged toner particles having an average particle size of less than about 5 microns, said toner particles comprising particles of a reaction product produced by the graft polymerization to carbon black of an alkyl ester of acrylic or methacrylic acid, and
Claim 21
Dependent Claim
109 words
A liquid developer for use in electrophotographic processes consisting essentially of: 1. a carrier liquid having a specific resistance of more than about 10 11 Ωcm selected from the group consisting of cyclohexane, decalin, kerosene, isoparaffinic hydrocarbon solvents, light oil, gasoline, chlorofluorinated hydrocarbon solvents and silicon oil, 2. from about 0.5 to about 50 parts by weight per 1000 parts by weight of said carrier liquid of positively charged toner particles having an average particle size of less than about 5 microns, said toner particles comprising particles of a reaction product produced by the graft polymerization to carbon black of an alkyl ester of acrylic or methacrylic acid, and
Claim 22
Dependent Claim
73 words
from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid of a copolymer of a half alkylamide of maleic acid and diisobutylene, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain.
Claim 23
Dependent Claim
73 words
from about 0.0003 to about 0.5 parts by weight per 1000 parts by weight of said carrier liquid of a copolymer of a half alkylamide of maleic acid and diisobutylene, the molar ratio of said half alkylamide of maleic acid to said diisobutylene in said copolymer being in the range of from about 1:1 to about 1:5 and said copolymer having from about 4 to about 50 monomer units in the copolymer chain.
Claim 24
Dependent Claim
14 words
The liquid developer of claim 16 wherein said carrier liquid is an isoparaffinic hydrocarbon.
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) | 1980-12-12 | 1981-06-13 | 1981-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-12 | 1985-06-13 | 1985-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-12 | 1989-06-13 | 1989-12-13 | $7700.00 | Window Closed / Lapsed |