Konica Minolta, Inc.

Konica Minolta Business Technologies, Inc.

Shinya Obara

Satoshi Uchino

Takuya Takahashi

Ikuko Sakurada

Futoshi Kadonome

Junya Ueda

Koji Shibata

Kaori Soeda

Tatsuya Fujisaki

Noriyuki Kimpara

Masahiro Anno

Shiro Hirano

Noboru Ueda

Naohiro Hirose

Junya Onishi

Takeo Oshiba

Okushi Okuyama

Kenshi Miyajima

So Matsuya

Tatsuya Nagase

Meizo Shirose

Kosuke Nakamura

Ryuichi Hiramoto

Hiroyuki Yasukawa

Yasuko Uchino

Natsuko Kusaka

Yohei Ohno

Hidehito Haruki

Keiji Arai

Yohei Maruyama

Provided is an electrostatic latent image developing toner including: toner base particles containing a binder resin and a white pigment; and an external additive, wherein silica particles are contained as the external additive, and the following relational expression (1) is satisfied, Relational expression (1): 0.70≤Wh_Si(B)/Wh_Si(A)≤0.95, in the above relational expression (1), Wh_Si (A) represents an NET intensity of a Si element contained in the white electrostatic latent image developing toner measured by wavelength dispersive X-ray fluorescence spectrometer, and Wh_Si (B) represents an NET intensity of a Si element contained in the white electrostatic latent image developing toner that has been ultrasonically dispersed in water.

Electrostatic latent image developing toner and electrostatic latent image developing toner set

A toner for electrostatic charge image development is a toner for electrostatic charge image development including toner particles containing a binder resin and an external additive, wherein the binder resin contains a crystalline polyester resin and an amorphous polyester resin, the external additive includes Al&#x2014;Si composite oxide particles, and a Si element content of the Al&#x2014;Si composite oxide particles is in the range of 50 to 90 mass % and a Si element ratio on surfaces of the Al&#x2014;Si composite oxide particles is in the range of 3 to 35 at %.

Toner for developing electrostatic charge image

To provide a two-component developer for electrostatic charge image development, the two-component developer enabling a high image quality to be kept and enabling the occurrence of fogging to be suppressed even in continuous printing of an image high in coverage rate. The two-component developer for electrostatic charge image development includes a toner particle including a toner base particle and an external additive disposed on the surface of the toner base particle, and a carrier particle including a core material particle and a covering section disposed on the surface of the core material particle, wherein the external additive includes an alumina particle, and the percentage of exposed area of the core material particle is 4.0% or more and 15.0% or less.

Two-component developer for electrostatic charge image development

Provided is an electrostatic latent image developing toner including toner mother particles having an external additive on a surface of the toner mother particles, wherein the external additive contains inorganic particles and aliphatic acid metal salt particles; the inorganic particles have a number average particle diameter in the range of 10 to 50 nm, and have a Mohs hardness of 8 or more; and the aliphatic acid metal salt particles have a number average particle diameter in the range of 0.4 to 2.0 &#x3bc;m.

Electrostatic latent image developing toner and image forming method

Provided is an electrostatic image developing toner containing toner mother particles having external additives on a surface of the mother particle, wherein the external additives contains calcium titanate particles having an average primary particle size in the range of 50 to 150 nm, and alumina particles; and an average primary particle size of the alumina particles is less than the average primary particle size of the calcium titanate particles.

Electrostatic image developing toner and image forming method

Provided is a two-component developer for developing an electrostatic latent image containing: toner particles having toner mother particles and an external additive on a surface of the toner mother particles; and carrier particles, wherein the external additive contains alumina particles; the alumina particles are subjected to a surface modification with a hydrophobilizing agent; among the hydrophobilizing agent existing on the surface of the alumina particles after the surface modification, a ratio of the hydrophobilizing agent in a state of being liberated from the surface is 20% or less when extraction treatment is performed under a predetermined condition; the alumina particles have a number average primary particle diameter in the range of 5 to 60 nm; and the carrier particles have a resin covering layer, and the resin covering layer is formed with an alicyclic (meth)acrylate monomer.

Two-component developer for developing electrostatic latent image

Provided is a two-component developer for developing an electrostatic latent image incorporating: toner particles each containing a toner mother particle having an external additive on a surface of the toner mother particle; and carrier particles each having a core material particle and a covering layer containing a resin on a surface of the core material particle, wherein the external additive contains inorganic particles; the inorganic particles are subjected to surface modification with silicone oil; a carbon content remained on a surface of the inorganic particle after the surface modification is within 3.0 to 10.0 mass %; a free carbon ratio on the surface of the inorganic particle is 70.0% or more; the carrier particles have a resistance in the range of 1.0&#xd7;10to 5.0&#xd7;10&#x3a9;&#xb7;cm; and the resin in the covering layer contains a resin formed from a monomer containing an alicyclic methacrylic acid ester monomer.

The disclosure concerns an electrostatic latent image developer including: a toner having toner base particles and an external additive; and a carrier, wherein the external additive contains silicone oil-treated silica and titanium oxide, Net intensity of titanium (Ti) in the toner to be measured by X-ray fluorescence analysis is 0.5 to 5 kcps, the carrier has a resin coating layer coating core material particles, and the resin coating layer has a constituent unit formed from an alicyclic (meth)acrylic acid ester.

Electrostatic latent image developer and method for producing electrostatic latent image developer

An electrostatically charged image developing toner includes a particulate toner matrix containing an external additive on the surface of the particulate toner matrix. The external additive includes silica particles A and silica particles B. The silica particles A have a number average primary-particle diameter in the range of 40 to 100 nm and an average circularity in the range of 0.50 to 0.90, and are surface-modified with silicone oil. The silica particles B have a number average primary-particle diameter of 25 nm or more and smaller than the number average primary-particle diameter of the silica particles A, and are surface-modified with alkylalkoxysilane having a specific structure or silazane.

Electrostatically charged image developing toner and electrostatically charged image developing two-component developer

An electrostatic charge image developing toner includes toner particles including a particulate toner matrix and an external additive adhering to a surface of the particulate toner matrix. The particulate toner matrix includes a crystalline polyester resin. The external additive includes silica particles. The silica particles are secondary particles including primary particles having a diameter in the range of 30 to 90 nm. The secondary particles have an average circularity in the range of 0.25 to 0.50. The secondary particles have an average aspect ratio of 3.0 or more.

Electrostatic charge image developing toner

A toner for developing electrostatic images, including toner particles containing an external additive on surfaces of toner matrix particles. The external additive contains at least a lanthanum-containing titanate compound.

Toner for developing electrostatic images

The toner of the present invention contains: a toner base particle, and a silica particle and a fatty acid metal salt particle adhering to a surface of the toner base particle. The toner base particle contains a crystalline polyester resin and an amorphous polyester resin. The toner particle has an average circularity of 0.945 to 0.965. The silica particle has a volume average particle size of 70 to 300 nm, and has an average circularity of 0.5 to 0.9. The fatty acid metal salt particle has a median diameter based on a volume of 0.50 to 2.00 &#x3bc;m.

Toner

An electrostatic latent image developing toner of the present invention includes toner base particles and particles containing a fatty acid metal salt. The toner base particles contain a crystalline resin containing a segment of a first resin and a segment of a second resin chemically bonded to each other and an amorphous resin containing at least the second resin. The crystalline resin is a hybrid crystalline polyester resin. The first resin is a crystalline polyester resin. The second resin is an amorphous resin. The volume-based median diameter (Da) of the toner base particles and the volume-based median diameter (Db) of the particles containing the fatty acid metal salt satisfy the relations represented by Expressions (1) and (2) below:0.5 &#x3bc;m&#x2266;&#x2266;2.0 &#x3bc;m&#x2003;&#x2003;Expression (1)0.1&#x2266;0.5.&#x2003;&#x2003;Expression (2)

Electrostatic latent image developing toner

Provided is an electrostatic image developing toner including a toner mother particle containing a colorant and a binder resin comprising a crystalline resin and an amorphous resin; and an external additive. The external additive includes an inorganic fine particle having a number average major axis in a range of 50 to 100 nm, an average aspect ratio in a range of 3 to 10, and a volume resistivity in a range of 1&#xd7;10to 1&#xd7;10&#x3a9;&#xb7;cm in primary particles.

Electrostatic image developing toner and two-component electrostatic image developer

Disclosed is a two-component developer containing toner particles and carrier particles. The number-average particle diameter of the toner particles MDt ranges from 3.5 to 5.0 &#x3bc;m. The MDt of the toner particles and the volume-average particle diameter of the carrier particles MDc are at a specific ratio, and spherical fine toner particles in the toner particles and fine carrier particles in the carrier particles exist at specific percentages.

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Fuchu, Japan

Shinya Obara