Patent EP0230041A2 successfully refreshed from Google Patents.
EP0230041A2
Expired / Lapsed
EP
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Process for producing toner through suspension polymerization
Assignee: Canon Inc
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Filing: 1986-12-23
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Granted: —
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Expires: 2006-12-23
Abstract
Abstract A dispersion stabilizer having a nitrogen-containing organic group and a water-soluble acidic substance are added to an aqueous medium. Into the aqueous medium, a monomer composition comprising at least a polymerizable monomer, an anionic polymer, a polymerization initiator and a colorant is added and dispersed therein into a prescribed particle size. The particles of the monomer composition are subjected to suspension polymerization. The resultant toner is caused to have a sharp particle size distribution and an improved anti-blocking property because of the combined effects of the dispersion stabilizer and the acidic substance contained in the aqueous medium and the anionic polymer contained in the monomer composition.
Inventors
- 👤 Yoshihiko Hyosu
- 👤 Hiromi Mori
- 👤 Eiichi Imai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 10:18
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/097; G03G9/09708; G03G9/09716; G03G9/0802; G03G9/0804; G03G9/0806
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
74 words
A process for producing a toner, comprising: adding a monomer composition comprising at least a polymerizable monomer, an anionic polymer, a polymerization initiator and a colorant, into an aqueous medium to which a dispersion stabilizer having a nitrogen-containing organic group and a water-soluble acidic substance have been added, dispersing the monomer composition into particles with a prescribed particle size in the aqueous medium, and subjecting the particles of the monomer composition to suspension polymerization.
Claim 2
Dependent Claim
74 words
A process for producing a toner, comprising: adding a monomer composition comprising at least a polymerizable monomer, an anionic polymer, a polymerization initiator and a colorant, into an aqueous medium to which a dispersion stabilizer having a nitrogen-containing organic group and a water-soluble acidic substance have been added, dispersing the monomer composition into particles with a prescribed particle size in the aqueous medium, and subjecting the particles of the monomer composition to suspension polymerization.
Claim 3
Dependent Claim
15 words
A process according to Claim 1, wherein said water-soluble acidic substance is a Broensted acid.
Claim 4
Dependent Claim
29 words
A process according to Claim 2, wherein said water-soluble substance is an inorganic acid selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.
Claim 5
Dependent Claim
17 words
A process according to Claim 2, wherein said water-soluble acidic substance is formic acid or lactic acid.
Claim 6
Dependent Claim
19 words
A process according to Claim 1, wherein said dispersion stabilizer is charged with δ ⊕ in the aqueous medium.
Claim 7
Dependent Claim
20 words
A process according to Claim 5, wherein said dispersion stabilizer has a - ⊕ - ion in the aqueous medium.
Claim 8
Dependent Claim
22 words
A process according to Claim 6, wherein said dispersion stabilizer comprises inorganic powder provided with an organic group comprising an amino group.
Claim 9
Dependent Claim
28 words
A process according to Claim 7, wherein said dispersion stabilizer comprises dry-process silica or wet-process silica treated with a coupling agent having a primary to quaternary amino group.
Claim 10
Dependent Claim
16 words
A process according to Claim 1, wherein said aqueous medium shows pH of 7 to 1.
Claim 11
Dependent Claim
17 words
A process according to Claim 9, wherein said aqueous medium shows a pH of 6.5 to 2.
Claim 12
Dependent Claim
17 words
A process according to Claim 10, wherein said aqueous medium shows a pH of 6.5 to 3.5.
Claim 13
Dependent Claim
27 words
A process according to Claim 1, wherein said anionic polymer is a polymer capable of moving to a ⊕ electrode in electrophoresis under pH 1 to 7.
Claim 14
Dependent Claim
28 words
A process according to Claim 1, wherein said monomer composition comprises 1 - 30 wt. parts of the anionic polymer per 100 wt. parts of the polymerizable monomer.
Claim 15
Dependent Claim
19 words
A process according to Claim 1, wherein said anionic polymer has a weight-average molecular weight of 5,000 - 500,000.
Claim 16
Dependent Claim
19 words
A process according to Claim 1, wherein said polymerizable monomer is a vinyl monomer having a reactive -C=C- group.
Claim 17
Dependent Claim
35 words
A process according to Claim 1, wherein said polymerizable monomer comprises a vinyl monomer selected from the group consisting of styrene, acrylic acid, alkyl acrylate ester, methacrylic acid, alkyl methacrylate ester, and mixtures of these.
Claim 18
Dependent Claim
15 words
A process according to Claim 1, wherein said monomer composition further comprises a crosslinking agent.
Claim 19
Dependent Claim
19 words
A process according to Claim 17, wherein said crosslinking agent is a monomer having at least two vinyl groups.
Claim 20
Dependent Claim
29 words
A process according to Claim 18, wherein said monomer composition contains 0.001 - 15 wt. % of the crosslinking agent based on the total amount of the polymerizable monomer.
Claim 21
Dependent Claim
28 words
A process according to Claim 19, wherein said monomer composition contains 0.1 - 10 wt.% of the crosslinking agent based on the total amount of the polymerizable monomer.
Claim 22
Dependent Claim
20 words
A process according to Claim 20, wherein the suspension polymerization is carried out at a temperature of 50°C or higher.
Claim 23
Dependent Claim
20 words
A process according to Claim 21, wherein the suspension polymerization is carried out at a temperature of 70 - 90°C.
References Cited (Backward Citations)
No citation records indexed.
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