Patent US3960737A successfully refreshed from Google Patents.
US3960737A
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US
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Negatively charged liquid developer for use in electrostatic photography
Assignee: Ricoh Co Ltd
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Filing: 1973-08-13
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Granted: 1976-06-01
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Expires: 1993-08-13
Abstract
Abstract Negatively charged liquid developers for use in electrostatic photography which comprises a highly insulating carrier liquid and, dispersed therein, a toner comprising colored particles coated with a synthetic polymer composition which is a mixture of vinyltoluene-butadiene or styrene-butadiene reaction products with acrylic and methacrylic acid and alkyl esters of such acids wherein the alkyl group contains 6 to 18 carbon atoms.
Inventors
- 👤 Toshiyuki Kawanishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:57
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13; G03G9/131; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/105
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
210 words
A negatively charged liquid developer for use in electrostatic photography which comprises a highly insulating carrier liquid and, dispersed therein, a toner comprising colored particles coated with a synthetic polymer composition comprising: 1. a mixture, A, of a copolymer (a) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates, wherein the alkyl group contains 6 to 18 carbon atoms; together with 2. a copolymer (b) having a molecular weight of from 5,000 to 30,000 comprising the reaction product of a monomer selected from the group consisting of acrylic and methacrylic acid with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates wherein the alkyl group contains 6 to 18 carbon atoms: the mixing weight ratio of copolymer (a) to copolymer (b) being from 1:2 to 15:1, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyltoluene to butadiene being from 1:1 to 9:1 the weight ratio of ester monomer to heteropolymer being from about 0.5:1 to 3:1, the weight ratio of acrylic or methacrylic acid to acid ester being from about 0.05:1 to 0.3:1.
Claim 2
Dependent Claim
210 words
A negatively charged liquid developer for use in electrostatic photography which comprises a highly insulating carrier liquid and, dispersed therein, a toner comprising colored particles coated with a synthetic polymer composition comprising: 1. a mixture, A, of a copolymer (a) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates, wherein the alkyl group contains 6 to 18 carbon atoms; together with 2. a copolymer (b) having a molecular weight of from 5,000 to 30,000 comprising the reaction product of a monomer selected from the group consisting of acrylic and methacrylic acid with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates wherein the alkyl group contains 6 to 18 carbon atoms: the mixing weight ratio of copolymer (a) to copolymer (b) being from 1:2 to 15:1, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyltoluene to butadiene being from 1:1 to 9:1 the weight ratio of ester monomer to heteropolymer being from about 0.5:1 to 3:1, the weight ratio of acrylic or methacrylic acid to acid ester being from about 0.05:1 to 0.3:1.
Claim 3
Dependent Claim
117 words
A liquid developer as in claim 1 wherein Mixture A, for each part by weight thereof, additionally contains up to 20 parts by weight of a copolymer (c) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an alkyl methacrylate wherein the alkyl group contains from 6 to 18 carbon atoms and a monomer selected from the group consisting of acrylic and methacrylic acid, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyl-toluene to butadiene being from 1:1 to 9:1, the weight ratio of heteropolymer to acid ester to acid being about 1:0.5 - 3:0.002 - 0.01.
Claim 4
Dependent Claim
35 words
A liquid developer as in claim 1 wherein the ester monomer of copolymer (a) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 5
Dependent Claim
35 words
A liquid developer as in claim 1 wherein the ester monomer of copolymer (b) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 6
Dependent Claim
35 words
A liquid developer as in claim 2 wherein the ester monomer of copolymer (a) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 7
Dependent Claim
35 words
A liquid developer as in claim 2 wherein the ester monomer of copolymer (b) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 8
Dependent Claim
34 words
A liquid developer as in claim 1 wherein copolymer (a) is the reaction product of lauryl methacrylate with a styrene-butadiene heteropolymer and copolymer (b) is the reaction product of lauryl methacrylate and acrylic acid.
Claim 9
Dependent Claim
34 words
A liquid developer as in claim 1 wherein copolymer (a) is the reaction product of 2-ethylhexyl methacrylate with a vinyltoluene-butadiene heteropolymer, and copolymer (b) is the reaction product of 2-ethylhexyl methacrylate and acrylic acid.
Claim 10
Dependent Claim
34 words
A liquid developer as in claim 1 wherein copolymer (a) is the reaction product of 2-ethylhexyl methacrylate and a styrene-butadiene heteropolymer and copolymer (b) is the reaction product of lauryl methacrylate and methacrylic acid.
Claim 11
Dependent Claim
49 words
A liquid developer as in claim 2 wherein copolymer (a) is the reaction product of lauryl methacrylate and a vinyltoluene-butadiene heteropolymer, copolymer (b) is the reaction product of 2-ethylhexyl methacrylate and methacrylic acid, and copolymer (c) is the reaction product of acrylic acid, tridecyl methacrylate and a vinyltoluene-butadiene heteropolymer.
Claim 12
Dependent Claim
197 words
A negatively charged toner for use in electrostatic photography comprising colored particles coated with a synthetic polymer composition comprising: 1. a mixture, A, of a copolymer (a) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates, wherein the alkyl group contains 6 to 18 carbon atoms; together with 2. a copolymer (b) having a molecular weight of from 5,000 to 30,000 comprising the reaction product of a monomer selected from the group consisting of acrylic and methacrylic acid with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates wherein the alkyl group contains 6 to 18 carbon atoms: the mixing weight ratio of copolymer (a) to copolymer (b) being from 1:2 to 15:1, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyltoluene to butadiene being from 1:1 to 9:1, the weight ratio of ester monomer to heteropolymer being from about 0.5:1 to 3:1, the weight ratio of acrylic or methacrylic acid to acid ester being from about 0.05:1 to 0.3:1.
Claim 13
Dependent Claim
197 words
A negatively charged toner for use in electrostatic photography comprising colored particles coated with a synthetic polymer composition comprising: 1. a mixture, A, of a copolymer (a) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates, wherein the alkyl group contains 6 to 18 carbon atoms; together with 2. a copolymer (b) having a molecular weight of from 5,000 to 30,000 comprising the reaction product of a monomer selected from the group consisting of acrylic and methacrylic acid with an ester monomer selected from the group consisting of alkyl acrylates and methacrylates wherein the alkyl group contains 6 to 18 carbon atoms: the mixing weight ratio of copolymer (a) to copolymer (b) being from 1:2 to 15:1, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyltoluene to butadiene being from 1:1 to 9:1, the weight ratio of ester monomer to heteropolymer being from about 0.5:1 to 3:1, the weight ratio of acrylic or methacrylic acid to acid ester being from about 0.05:1 to 0.3:1.
Claim 14
Dependent Claim
116 words
A toner as in claim 11 wherein Mixture A, for each part by weight thereof, additionally contains up to 20 parts by weight of a copolymer (c) comprising the reaction product of a heteropolymer selected from the group consisting of styrene-butadiene heteropolymers and vinyltoluene-butadiene heteropolymers with an alkyl methacrylate wherein the alkyl group contains from 6 to 18 carbon atoms and a monomer selected from the group consisting of acrylic and methacrylic acid, the molecular weight of a heteropolymer being from 50,000 to 300,000 and the weight ratio of styrene or vinyltoluene to butadiene being from 1:1 to 9:1, the weight ratio of heteropolymer to acid ester to acid being about 1:0.5 - 3:0.002 - 0.01.
Claim 15
Dependent Claim
34 words
A toner as in claim 11 wherein the ester monomer of copolymer (a) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 16
Dependent Claim
34 words
A toner as in claim 11 wherein the ester monomer of copolymer (b) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 17
Dependent Claim
34 words
A toner as in claim 12 wherein the ester monomer of copolymer (a) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 18
Dependent Claim
34 words
A toner as in claim 12 wherein the ester monomer of copolymer (b) is selected from the group consisting of hexyl, decyl, lauryl and stearyl acrylate; and hexyl, 2-ethylhexyl, decyl, lauryl and stearyl methacrylate.
Claim 19
Dependent Claim
33 words
A toner as in claim 11 wherein copolymer (a) is the reaction product of lauryl methacrylate with a styrene-butadiene heteropolymer and copolymer (b) is the reaction product of lauryl methacrylate and acrylic acid.
Claim 20
Dependent Claim
33 words
A toner as in claim 11 wherein copolymer (a) is the reaction product of 2-ethylhexyl methacrylate with a vinyltoluene-butadiene heteropolymer, and copolymer (b) is the reaction product of 2-ethylhexyl methacrylate and acrylic acid.
Claim 21
Dependent Claim
33 words
A toner as in claim 11 wherein copolymer (a) is the reaction product of 2-ethylhexyl methacrylate and a styrene-butadiene heteropolymer and copolymer (b) is the reaction product of lauryl methacrylate and methacrylic acid.
Claim 22
Dependent Claim
47 words
A toner as in claim 12 wherein copolymer (a) is the reaction product of lauryl methacrylate and a vinyltoluene-butadiene heteropolymer, copolymer (b) is the reaction product of 2-ethylhexyl methacrylate and methacrylic acid, and copolymer (c) is the reaction product of acrylic acid, tridecyl methacrylate and vinyltoluene-butadiene heteropolymer.
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) | 1979-06-01 | 1979-12-01 | 1980-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-01 | 1983-12-01 | 1984-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-01 | 1987-12-01 | 1988-06-01 | $7700.00 | Window Closed / Lapsed |