EP0217337A2
Expired / Lapsed
EP
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Encapsulated toner
Assignee: Canon Inc
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Filing: 1986-09-29
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Granted: —
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Expires: 2006-09-29
Abstract
Abstract An encapsulated toner is provided by coating core particles with an outer shell. The outer shell comprises, as predominant components thereof, vinyl polymers A and B of different molecular weights. More specifically, the ratio of the number-average molecular weight of the vinyl polymer A (Mn<sub>A</sub>) to that of the vinyl polymer B (Mn<sub>B</sub>) is in the range of 2 to 15. The vinyl polymers A and B respectively have a ratio of weight-average molecular weight to number-average molecular weight of 5 or less. Because of these specific molecular weight characteristics of the shell-constituting polymers, the durability and triboelectric charging characteristics of the encapsulated toner are improved. These effects are enhanced particularly when inorganic fine particles are attached to embedded in the surface or surface layer of the core particles.
Inventors
- 👤 Toshiaki Nakahara
- 👤 Ichiro Ohsaki
- 👤 Hisayuki Ushiyama
- 👤 Masashi Kiuchi
- 👤 Masuo Yamazaki
- 👤 Yasuhide Goseki
- 👤 Hisayuki Ochi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 04:02
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08726; G03G9/08728; G03G9/093; G03G9/09307; G03G9/09314; G03G9/09321; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
98 words
An encapsulated toner for developing electrostatic images, comprising microcapsules each comprising: a core particle and an outer shell coating the core particles; the outer shell comprising, as predominant components thereof, a vinyl polymer A and a vinyl polymer B of different number-average molecular weights; the ratio of the number-average molecular weight of the vinyl polymer A (Mn A ) to that of the vinyl polymer B (Mn B ) being in the range of 2 to 15; the vinyl polymers A and B respectively having a ratio of weight-average molecular weight to number-average molecular weight of or less.
Claim 2
Dependent Claim
98 words
An encapsulated toner for developing electrostatic images, comprising microcapsules each comprising: a core particle and an outer shell coating the core particles; the outer shell comprising, as predominant components thereof, a vinyl polymer A and a vinyl polymer B of different number-average molecular weights; the ratio of the number-average molecular weight of the vinyl polymer A (Mn A ) to that of the vinyl polymer B (Mn B ) being in the range of 2 to 15; the vinyl polymers A and B respectively having a ratio of weight-average molecular weight to number-average molecular weight of or less.
Claim 3
Dependent Claim
26 words
The encapsulated toner according to Claim 1, wherein said vinyl polymer A is a copolymer of a styrene monomer and a tertiary amino group-containing vinyl monomer.
Claim 4
Dependent Claim
32 words
The encapsulated toner according to Claim 1, wherein said vinyl polymer A and said vinyl polymer B are respectively a copolymer of a styrene monomer and a tertiary amino group-containing vinyl monomer.
Claim 5
Dependent Claim
31 words
The encapsulated toner according to Claim 3, wherein said copolymer has a copolymerization ratio of the styrene monomer to the tertiary amino group-containing monomer in the range of 1:0.01 to 1:0.5.
Claim 6
Dependent Claim
22 words
The encapsulated toner according to Claim 1, wherein the ratio Mn A /Mn B is in the range of 3 to 10.
Claim 7
Dependent Claim
29 words
The encapsulated toner according to Claim 1, wherein said outer shell comprises the vinyl polymer A and the vinyl polymer B in a weight ratio of 1:4 to 10:1.
Claim 8
Dependent Claim
35 words
The encapsulated toner according to Claim 6, wherein said vinyl polymer A has an Mn A value of 2,000 - 225,000, and said vinyl polymer B has an Mn B value of 1,000 - 15,000.
Claim 9
Dependent Claim
29 words
The encapsulated toner according to Claim 1, wherein said core particle comprises inorganic fine particles attached to or embedded in the surface or surface layer of the core particles.
Claim 10
Dependent Claim
30 words
The encapsulated toner according to Claim 8, wherein said inorganic fine particles have a specific surface area of 50 - 400 m²/g according to the BET method by N₂ adsorption.
Claim 11
Dependent Claim
16 words
The encapsulated toner according to Claim 9, wherein said inorganic fine particles are silica fine particles.
Claim 12
Dependent Claim
24 words
The encapsulated toner according to Claim 1, wherein said core particle comprises a soft solid material showing pressure-fixability, and a colorant or magnetic powder.
Claim 13
Dependent Claim
21 words
The encapsulated toner according to Claim 11, wherein said core particle has a volume-average particle size of 5 - 20 µ.
Claim 14
Dependent Claim
15 words
The encapsulated toner according to Claim 11, wherein said soft solid material comprises a wax.
Claim 15
Dependent Claim
24 words
The encapsulated toner according to Claim 11, wherein said soft solid material comprises a reaction product between an amino group-containing monomer and a wax.
Claim 16
Dependent Claim
21 words
The encapsulated toner according to Claim 14, wherein said amino group-containing monomer is dimethylaminoethyl methacrylate, and said wax is paraffin wax.
Claim 17
Dependent Claim
26 words
The encapsulated toner according to Claim 1, wherein said outer shell comprises the vinyl polymers A and B in a proportion of 60 wt.% or more.
Claim 18
Dependent Claim
61 words
The encapsulated toner according to Claim 1, wherein said core particle comprises inorganic fine particles attached to or embedded in the surface or surface layer of the core particle, said outer shell comprises the vinyl polymers A and B in a proportion of 60 wt.% or more, and said outer shell has been formed by phase separation from an organic phase.
Claim 19
Dependent Claim
28 words
The encapsulated toner according to Claim 17, wherein said core particle comprises a reaction product between paraffin wax and dimethylaminoethyl methacrylate, polyethylene wax, paraffin wax and carnauba wax.
Claim 20
Dependent Claim
31 words
The encapsulated toner according to Claim 18, wherein said core particle has been coated with the outer shell comprising the vinyl polymers A and B respectively comprising a styrene-dimethylaminoethyl methacrylate copolymer.
References Cited (Backward Citations)
No citation records indexed.
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