US4033890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid developer for electrophotography
Assignee: Fujifilm Holdings Corp
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Filing: 1975-02-26
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Granted: 1977-07-05
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Expires: 1995-02-26
Abstract
Abstract Novel liquid developers contain in a carrier liquid a toner produced by graft-copolymerization of an addition-polymerizable monomer represented by the formula: ##STR1## wherein R 1 represents a hydrogen atom or a methyl group and R 2 represents an alkyl group having 6 to 20 carbon atoms, an addition-polymerizable monomer having an alkoxysilane group or a phenoxysilane group, and carbon black. The carrier liquid has a high electric resistance and a low dielectric constant.
Inventors
- 👤 Yasuo Tamai
- 👤 Satoru Honjo
- 👤 Sadao Osawa
- 👤 Masato Satomura
- 👤 Chiaki Osada
- 👤 Wakio Nagashima
- 👤 Naomitsu Takashina
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:36
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/131; G03G9/133
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
187 words
An electrophotographic liquid developer comprising an insulating carrier liquid having a high electric resistance and a low dielectric constant and a toner in a proportion of about 0.1 to about 20 parts by weight of said toner per 1,000 parts by weight of said carrier liquid, said toner comprising the graft-copolymer of (a) an addition-polmerizable monomer (A) represented by the formula: ##STR5## where R 1 represents a hydrogen atom or a methyl group and R 2 represents an alkyl group having 6 to 20 carbon atoms, and (b) an addition-polymerizable monomer (B) having an alkoxysilane group or a phenoxysilane group, and pigment particles selected from the group consisting of carbon black, aniline black, alkali blue, nigrosine, phthalocyanine blue and phthalocyanine green, with the proportion of addition polymerizable monomer (A) to addition polymerizable monomer (B) being 5 to 45 parts by weight of addition polymerizable monomer (A) per 1 part by weight of addition polymerizable monomer (B) and with the amount of addition polymerizable monomer (A) and addition polymerizable monomer (B) grafted to the pigment particles being sufficient to provide the pigment particles with an effective positive charge.
Claim 2
Dependent Claim
187 words
An electrophotographic liquid developer comprising an insulating carrier liquid having a high electric resistance and a low dielectric constant and a toner in a proportion of about 0.1 to about 20 parts by weight of said toner per 1,000 parts by weight of said carrier liquid, said toner comprising the graft-copolymer of (a) an addition-polmerizable monomer (A) represented by the formula: ##STR5## where R 1 represents a hydrogen atom or a methyl group and R 2 represents an alkyl group having 6 to 20 carbon atoms, and (b) an addition-polymerizable monomer (B) having an alkoxysilane group or a phenoxysilane group, and pigment particles selected from the group consisting of carbon black, aniline black, alkali blue, nigrosine, phthalocyanine blue and phthalocyanine green, with the proportion of addition polymerizable monomer (A) to addition polymerizable monomer (B) being 5 to 45 parts by weight of addition polymerizable monomer (A) per 1 part by weight of addition polymerizable monomer (B) and with the amount of addition polymerizable monomer (A) and addition polymerizable monomer (B) grafted to the pigment particles being sufficient to provide the pigment particles with an effective positive charge.
Claim 3
Dependent Claim
115 words
The developer of claim 1 wherein said addition-polmerizable monomer (B) is represented by the formula: ##STR6## where R 3 is a hydrogen atom or a methyl group, R 4 is an alkylene group having 1 to 8 carbon atoms, and R 5 , R 6 and R 7 each is an alkyl group having 1 to 4 carbon atoms or a phenyl group; or ##STR7## where R 8 , R 9 and R 10 each is a phenyl group, an alkyl group having 1 to 4 carbon atoms or a --CH 2 --CH 2 -- OR 11 group wherein R 11 represents a phenyl group or an alkyl group having 1 to 4 carbon atoms.
Claim 4
Dependent Claim
28 words
The developer of claim 1, where said insulating liquid carrier has an electrical resistance of at least 10 10 ohm-cm and a dielectric constant of lower than 3.
Claim 5
Dependent Claim
33 words
The developer of claim 3, where said insulating liquid carrier is a straight chain aliphatic hydrocarbon, a branched chain aliphatic hydrocarbon, a chlorofluorohydrocarbon, kerosene, gasoline, ligroin, mineral spirits or an isoparaffinic solvent mixture.
Claim 6
Dependent Claim
37 words
The developer of claim 1, where a charge regulating agent is additionally present, said charge regulating agent being selected from the group consisting of metallic salts of 2-ethylhexanoic acid, and borates or silicates of long chain alcohols.
Claim 7
Dependent Claim
35 words
The developer of claim 4, where said charge regulating agent is manganese linolenate, cobalt naphthenate, manganese resinate, cobalt oleate, a metal salt of 2-ethylhexanoic acid or a borate or silicate of a long chain alcohol.
Claim 8
Dependent Claim
25 words
The developer of claim 1, where said addition-polymerizable monomer (B) is γ-trimethoxysilane-n-propyl methacrylate, γ-triethoxysilane-n-propylmethacrylate, γ-trimethoxysilane-tert-butylmethacrylate, γ-trimethoxysilane-ethylacrylate, γ-trimethoxysilane-ethylhexylacrylate, vinyl-tri-β-(methoxyethoxy)silane, vinyl-tri-β-(methoxymethoxy)silane, vinyl-tri-β-(methoxyphenoxy)silane, vinyl-trimethoxysilane, vinyl-triethoxysilane, vinyl-tributoxysilane or vinyl-triphenoxysilane.
Claim 9
Dependent Claim
16 words
The developer of claim 1, where said addition-polymer-polymerizable monomer (A) is lauryl methacrylate or cetyl acrylate.
Claim 10
Dependent Claim
50 words
The developer of claim 1, wherein the amount of the pigment particles to the amount of the addition polymerizable monomers (A) and (B) ranges from about 0.2 to about 6 parts by weight of said pigment particles per 1 part by weight of said addition polymerizable monomers (A) and (B).
Claim 11
Dependent Claim
25 words
The developer of claim 5 wherein 0.001 to about 5 parts by weight of charge regulating agent is added per 1,000 parts of carrier liquid.
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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) | 1980-07-04 | 1981-01-03 | 1981-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-04 | 1985-01-03 | 1985-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-04 | 1989-01-03 | 1989-07-05 | $7700.00 | Window Closed / Lapsed |