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US4592990A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing toner

Assignee: Canon Inc
•
Filing: 1983-12-21
•
Granted: 1986-06-03
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Expires: 2003-12-21
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Abstract

Abstract A process for producing toner, which comprises dispersing a monomer system comprising a polymerizable monomer and a polar polymer in a dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer, and subjecting said monomer system to the suspension polymerization. By this process, toner particles excellent in fixing characteristic, developing characteristic and abrasion resistance can be obtained with a narrow particle size distribution.

Inventors

  • 👤 Seiichi Takagi
  • 👤 Yoshihiko Hyosu
  • 👤 Masumi Sasakawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 05:39
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/44; G; G03; G03G; G03G9/00; G03G9/08; G03G9/0802; G03G9/0804; G03G9/0806; G03G9/097; G03G9/09708; G03G9/09725; G03G9/09783

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 180 words
A polymerization process for producing a pseudo-capsule toner, comprising sequentially: (a) mixing a polymerizable unsaturated monomer, a polar polymer selected from the group consisting of a cationic polymer and an anionic polymer, a colorant or a magnetic powder, and a polymerization initiator to obtain a monomer system containing said unsaturated monomer, said colorant or said magnetic powder, said polymerization initiator, and said polar polymer dissolved in said unsaturated monomer; (b) dispersing the obtained monomer system in an aqueous dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer to form suspended particles of said monomer system in which said polymer collects at the surface of the suspended particles through electrostatic interaction with said dispersant; and (c) suspension polymerizing said monomer system in said aqueous dispersion medium to obtain particles containing a polymer obtained from said monomer, said polar polymer and said colorant or said magnetic powder; wherein the resulting particles have a pseudo-capsule structure in which said polar polymer is concentrated at the surface of each of said particles for use as a toner.
Claim 2
Dependent Claim 180 words
A polymerization process for producing a pseudo-capsule toner, comprising sequentially: (a) mixing a polymerizable unsaturated monomer, a polar polymer selected from the group consisting of a cationic polymer and an anionic polymer, a colorant or a magnetic powder, and a polymerization initiator to obtain a monomer system containing said unsaturated monomer, said colorant or said magnetic powder, said polymerization initiator, and said polar polymer dissolved in said unsaturated monomer; (b) dispersing the obtained monomer system in an aqueous dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer to form suspended particles of said monomer system in which said polymer collects at the surface of the suspended particles through electrostatic interaction with said dispersant; and (c) suspension polymerizing said monomer system in said aqueous dispersion medium to obtain particles containing a polymer obtained from said monomer, said polar polymer and said colorant or said magnetic powder; wherein the resulting particles have a pseudo-capsule structure in which said polar polymer is concentrated at the surface of each of said particles for use as a toner.
Claim 3
Dependent Claim 37 words
A process according to claim 1, wherein the monomer system is dispersed in the aqueous dispersion medium containing 0.1 to 10% by weight of the dispersant having a charging polarity opposite to that of the polar polymer.
Claim 4
Dependent Claim 23 words
A process according to claim 2, wherein the monomer system is polymerized by suspension polymerization at a temperature not lower than 50° C.
Claim 5
Dependent Claim 65 words
A process according to claim 1, wherein the monomer system comprises 100 parts by weight of the polymerizable unsaturated monomer, 0.5 to 50 parts by weight of the polar polymer, 0.1 to 10% by weight of the polymerization initiator and 2 to 10 parts by weight of the colorant based on 100 parts by weight of the total of the monomer and the polar polymer.
Claim 6
Dependent Claim 65 words
A process according to claim 1, wherein the monomer system comprises 100 parts by weight of the polymerizable unsaturated monomer, 0.5 to 50 parts by weight of the polymer, 0.1 to 10% by weight of the polymerization initiator and 15 to 100 parts by weight of the magnetic powder based on 100 parts by weight of the total of the monomer and the polar polymer.
Claim 7
Dependent Claim 34 words
A process according to claim 1, wherein the polar polymer is a cationic polymer having a cationic group and the dispersant is an anionic dispersant having an anionic charge in the aqueous dispersion medium.
Claim 8
Dependent Claim 23 words
A process according to claim 6, wherein the dispersant is an anionic inorganic dispersant having an anionic charge in the aqueous dispersion medium.
Claim 9
Dependent Claim 14 words
A process according to claim 7, wherein the anionic inorganic dispersant is colloidal silica.
Claim 10
Dependent Claim 33 words
A process according to claim 6, wherein the dispersant is an anionic organic dispersant selected from the group consisting of partially saponified polyvinyl acetate and partially saponified product of copolymer of vinyl acetate.
Claim 11
Dependent Claim 38 words
A process according to claim 6, wherein the cationic polymer is a homopolymer of cationic monomer or a copolymer of a cationic monomer and a copolymerizable monomer therewith in which said cationic monomer is a nitrogen containing monomer.
Claim 12
Dependent Claim 18 words
A process according to claim 10, wherein the cationic polymer has a molecular weight of 5000 to 500,000.
Claim 13
Dependent Claim 23 words
A process according to claim 11, wherein the copolymerizable monomer is styrene, styrene derivative, ethylenically unsaturated monoolefin or alpha-methylene aliphatic monocarboxylic acid ester.
Claim 14
Dependent Claim 34 words
A process according to claim 1, wherein the polar polymer is an anionic polymer having an anionic group and the dispersant is a cationic dispersant having a cationic charge in the aqueous dispersion medium.
Claim 15
Dependent Claim 24 words
A process according to claim 13, wherein the cationic dispersant is a cationic inorganic dispersant having a cationic charge in the aqueous dispersion medium.
Claim 16
Dependent Claim 19 words
A process according to claim 14, wherein the cationic dispersant is aluminum oxide or positively chargable hydrophilic colloidal silica.
Claim 17
Dependent Claim 35 words
A process according to claim 14, wherein the anionic polymer is a polymer having a molecular weight of 5000 to 500,000 and having hydroxyl group, carboxyl group, sulfonic acid group, phosphoxy group or acid anhydride.
Claim 18
Dependent Claim 28 words
A process according to claim 16, wherein the anionic polymer is a homopolymer of anionic monomer or a copolymer of an anionic monomer and a copolymerizable monomer therewith.
Claim 19
Dependent Claim 19 words
A process according to claim 17, wherein the copolymerizable monomer is styrene, monoolefin or alpha-methylene aliphatic monocarboxylic acid ester.
Claim 20
Dependent Claim 37 words
A process according to claim 1, wherein the monomer system further contains a hydrocarbon compound selected from the group consisting of paraffin having 6 or more carbon atoms and a polyolefin having 6 or more carbon atoms.
Claim 21
Dependent Claim 31 words
A process according to claim 1, wherein the particles obtained by the suspension polymerization are further treated with a silane coupling agent or a titanate coupling agent to remove hygroscopicity thereof.
Claim 22
Dependent Claim 27 words
A process according to claim 1, wherein the particles obtained by the suspension polymerization are further treated with an alkali to eliminate the dispersant from the particles.
Claim 23
Dependent Claim 176 words
A pseudo-capsule toner obtained by: (a) mixing a polymerizable unsaturated monomer, a polar polymer selected from the group consisting of a cationic polymer and an anionic polymer, a colorant or a magnetic powder and a polymerization initiator to obtain a monomer system containing said unsaturated monomer, said colorant or magnetic powder, said polymerization initiator and said polar polymer dissolved in said unsaturated monomer; (b) dispersing the obtained monomer system in an aqueous dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer therein to form suspended particles of said monomer system in which said polar polymer collects at the surface of the suspended particles through electrostatic interaction with said dispersant; and (c) suspension polymerizing said monomer system in said aqueous dispersion medium to obtain particles containing a polymer obtained from said monomer, said polar polymer and said colorant or said magnetic powder, wherein the resulting particles have a pseudo-capsule structure in which said polar polymer is concentrated at the surface of each of said particles for use as a toner.
Claim 24
Dependent Claim 176 words
A pseudo-capsule toner obtained by: (a) mixing a polymerizable unsaturated monomer, a polar polymer selected from the group consisting of a cationic polymer and an anionic polymer, a colorant or a magnetic powder and a polymerization initiator to obtain a monomer system containing said unsaturated monomer, said colorant or magnetic powder, said polymerization initiator and said polar polymer dissolved in said unsaturated monomer; (b) dispersing the obtained monomer system in an aqueous dispersion medium containing a dispersant having a charging polarity opposite to that of said polar polymer therein to form suspended particles of said monomer system in which said polar polymer collects at the surface of the suspended particles through electrostatic interaction with said dispersant; and (c) suspension polymerizing said monomer system in said aqueous dispersion medium to obtain particles containing a polymer obtained from said monomer, said polar polymer and said colorant or said magnetic powder, wherein the resulting particles have a pseudo-capsule structure in which said polar polymer is concentrated at the surface of each of said particles for use as a toner.

References Cited (Backward Citations)

US3959153A Cited
US3720617A Cited
US3983045A Cited
US4386147A Cited
US3997488A Cited
US4100087A Cited
US4231919A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-06-02 1989-12-02 1990-06-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-06-02 1993-12-02 1994-06-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-06-02 1997-12-02 1998-06-03 $7700.00 Window Closed / Lapsed

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