US 9,606,462 B2Granted

Toner and method for manufacturing toner

AssigneeCanon Kabushiki Kaisha

InventorsShotaro Nomura, Koji Nishikawa, Kosuke Fukudome, Daisuke Yoshiba, Shohei Tsuda, Hiroki Akiyama, Katsuhisa Yamazaki

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Abstract

To provide a toner from which an image having a stable image density can be obtained with reduced occurrence of pollution of members, even when a toner container is filled with a larger amount of toner than a conventional amount for long-term use. A toner including a toner particle and an external additive containing an organic-inorganic composite fine particle and an inorganic fine particle A; wherein the organic-inorganic composite fine particle includes a resin particle and an inorganic fine particle B, the resin particle has a surface with a convex derived from the inorganic fine particle B; has a specific number average particle diameter (D1) and a specific shape factor SF-2; and has a specific fixed state to the toner particle; the organic-inorganic composite fine particle has a specific unit diffusion index on the toner particle surface; the inorganic fine particle A has a specific BET specific surface area.

Claims6

Dependent claims

A toner comprising a toner particle containing a binder resin, a colorant and a releasing agent, and an external additive containing (i) an organic-inorganic composite fine particle having a number average particle diameter (D1) of 50-500 nm and a shape factor SF-2 of 103-120 as measured at a magnification of 200,000, and (ii) an inorganic fine particle A having a BET specific surface area of 50-400 m2/g, wherein

the organic-inorganic composite fine particle:
(1) comprises a resin particle and an inorganic fine particle B which is embedded in the resin particle, and has a surface with a convex portion derived from the inorganic fine particle B;
(2) has a proportion Y (parts by mass) of a particle firmly fixed to the toner particle of 0.45 to 3.00 parts by mass with respect to 100 parts by mass of the toner particle;
and
(3) X-Y≦0.30 when a content proportion of the organic-inorganic composite fine particle is X parts by mass with respect to 100 parts by mass of the toner particle;
the organic-inorganic composite fine particle has a unit diffusion index of 0.75 or more on the toner particle surface when unit diffusion index=(organic-inorganic composite fine particle coverage ratio on toner particle surface obtained from measurement)/(organic-inorganic composite fine particle coverage ratio on toner particle surface for ideal diffusion of organic-inorganic composite fine particle).

3 more elements

A method for manufacturing a toner including a toner particle containing a binder resin, a colorant and a releasing agent, and an external additive containing (i) an organic-inorganic composite fine particle having a number average particle diameter (D1) of 50-500 nm and a shape factor SF-2 of 103-120 as measured at a magnification of 200,000, and (ii) an inorganic fine particle A having a BET specific surface area of 50-400 m2/g, comprising:

(A) a first mixing step of mixing the toner particle and the organic-inorganic composite fine particle using a treating apparatus having a rotator in a treatment chamber so as to produce a mixture;
and
(B) a second mixing step of mixing the mixture and the inorganic fine particle A using a treating apparatus having a rotator in a treatment chamber so as to produce a toner, wherein
the organic-inorganic composite fine particle:
(1) comprises a resin particle and an inorganic fine particle B which is embedded in the resin particle, and has a surface with a convex portion derived from the inorganic fine particle B;
(2) has a proportion Y (parts by mass) of a particle firmly fixed to the toner particle of 0.45 to 3.00 parts by mass with respect to 100 parts by mass of the toner particle;
and
(3) X-Y≦0.30 when a content proportion of the organic-inorganic composite fine particle is X parts by mass with respect to 100 parts by mass of the toner particle;
the organic-inorganic composite fine particle has a unit diffusion index of 0.75 or more on the toner particle surface when unit diffusion index=(organic-inorganic composite fine particle coverage ratio on toner particle surface obtained from measurement)/(organic-inorganic composite fine particle coverage ratio on toner particle surface for ideal diffusion of organic-inorganic composite fine particle).

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/814,873Filed 31 Jul 2015
Priority: JP 2014-1614797 Aug 2014
Published: US 2016/0041481 A111 Feb 2016
Granted: 28 Mar 2017
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

G03G 9/0825
With toner particles: characterised by their structure; characterised by non-homogenuous distribution of components
G03G 9/0808
Preparation methods: by dry mixing the toner components in solid or softened state
G03G 9/0827
With toner particles: characterised by their shape, e.g. degree of sphericity
G03G 9/09708
Plasticisers; Charge controlling agents: inorganic compounds