Konica Minolta, Inc.

Konica Minolta Business Technologies, Inc.

Junya Ueda

Shinya Obara

Takuya Takahashi

Shiro Hirano

Satoshi Uchino

Takaki Kawamura

Ikuko Sakurada

Junya Onishi

Yasuko Uchino

Anju Hori

Natsuko Fujisaki

Kenshi Miyajima

Koji Shibata

Kosuke Nakamura

Hiroyuki Kozuru

Yoshiyasu Matsumoto

Takanari Kayamori

Yohei Maruyama

Kawamura Takaki

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

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 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

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

An electrostatic image developing toner including a toner particle, wherein the toner particle contains a vinyl resin which is a polymer of a vinyl monomer having an acid group, a polyester resin, at least one of aluminum (Al) and magnesium (Mg), and tin (Sn), and when net intensities of Al, Mg and Sn in the toner particle measured by fluorescent X-ray analysis are respectively expressed as I, Iand I, a ratio (I+I)/Iis within a range of 0.5 to 2.5.

Electrostatic image developing toner

The toner of the present invention is an electrostatic latent image developing toner, and has a toner base particle. The toner base particle contains a binder resin including a crystalline resin, and a release agent. The toner has the maximum value G'at a temperature equal to or lower than Tm, among specific storage elastic modulus ratios, of 2.2 or more. The Tm represents a peak top temperature (&#xb0; C.) of a specific endothermic peak in DSC of the toner.

Toner

An image forming method forms a color toner image and a white toner image using an image forming apparatus having a plurality of developing machines. The color toner image is formed using a color developer containing a first carrier and at least one color toner selected from a yellow toner, a magenta toner, and a cyan toner. The white toner image is formed using a white developer containing a second carrier and a white toner containing at least titanium oxide as a pigment. Formula (1):Iw&#x3c;Ic&#x2003;&#x2003;(1)is satisfied. Ic (&#x3bc;A) is a dynamic current value of the first carrier at 100 V and Iw (&#x3bc;A) is a dynamic current value of the second carrier at 100 V.

Image forming method, electrostatic charge image developer set, and image forming apparatus

The invention provides an image formation method, a toner set, and a white toner, by which a masking function of an image layer formed by a white toner on a recording medium can be developed efficiently, and low temperature fixability can be improved. An image formation method for fixing an image forming layer (A) to be formed using a white toner, and an image forming layer (B) to be formed adjacent to the image forming layer (A) using a toner different from the white toner on a recording medium; wherein the following relational expressions (1) and (2) are satisfied:1.000&#x3c;&#x3c;1.300&#x2003;&#x2003; (1);and1.000&#x3c;&#x3c;1.060&#x2003;&#x2003;(2).

Image formation method, toner set, and white toner

Disclosed is a production method of a two-component developer for developing an electrostatic image comprising a toner and a resin coated carrier having a porous magnetic core particle and a resin coated layer, wherein the porous magnetic core particle are composed of a porous ferrite material and have pore apertures on a surface of the particle, and the method comprises steps of blocking the pore apertures of the porous magnetic core particle with rubber particles by dry mixing of the porous magnetic core particle and the rubber particles, forming the resin coated carrier by forming a resin layer on the porous magnetic core particle whose pore apertures have been blocked, and mixing the resin coated carrier and the toner.

Growing community of inventors

Hino, Japan

Junya Ueda