Kyocera Document Solutions Inc.

Haruhiro Nishitera

Ryotaro Komada

Jun Hioki

Masami Tsujihiro

Yusuke Washino

Tomoyasu Asakawa

A toner includes a plurality of first particles and a plurality of second particles. The first particles and the second particles each include a core and a shell layer covering a surface of the core. The cores of the first particles contain a binder resin and a colorant. The cores of the second particles contain a releasing agent. A standard deviation of a volume-based particle size distribution of the toner is no greater than 1.28. An area ratio of regions of the cores of the second particles that are occupied by the releasing agent in a cross-sectional image of the second particles is at least 50%. A number ratio of the second particles is at least 5% and no greater than 25% relative to a total number of the first particles and the second particles.

Toner

An electrostatic latent image developing toner includes toner particles each including a toner core and a shell layer covering a surface of the toner core. The shell layer contains a hydrophilic thermosetting resin and a hydrophobic thermoplastic resin. The hydrophobic thermoplastic resin is exposed at surfaces of the toner particles. In a preferable configuration of the shell layer, a plurality of blocks substantially formed from the hydrophobic thermoplastic resin are connected to one another through a junction portion substantially formed from the hydrophilic thermosetting resin.

Electrostatic latent image developing toner

An electrostatic latent image developing toner includes a plurality of toner particles containing a binder resin. The toner particles have a cross-linking structure originating from a high-molecular cross-linking agent. A storage elastic modulus of the toner at a temperature of 80&#xb0; C. is at least 1.0&#xd7;10Pa and no greater than 5.0&#xd7;10Pa. A storage elastic modulus of the toner at a temperature of 120&#xb0; C. is at least 1.0&#xd7;10Pa and no greater than 1.0&#xd7;10Pa. A cross-linking density Nx represented by formula (1) is at least 2.9&#xd7;10mol/cmand no greater than 2.5&#xd7;10mol/cm. A loss tangent tan &#x3b4;x represented by formula (2) is at least 0.05 and no greater than 0.50.=10&#xd7;&#xd7;(+343)&#x2003;&#x2003;(1)tan &#x3b4;&#x2003;&#x2003;(2)

Electrostatic latent image developing toner and method for producing the same

An electrostatic latent image developing toner includes a plurality of toner particles () each including a toner mother particle () and an external additive adhering to a surface of the toner mother particle (). The toner mother particles () contain a crystalline polyester resin and a non-crystalline polyester resin. The toner particles () include, as the external additive, crystal nucleating agent particles () containing a crystal nucleating agent for promoting crystallization of the crystalline polyester resin. On a differential scanning calorimetry spectrum of the toner before fixing, an endotherm quantity of a heat absorption peak originating from a crystalline region of the crystalline polyester resin is less than 2.0 mJ/mg. On a differential scanning calorimetry spectrum of the toner after fixing, an endotherm quantity of a heat absorption peak originating from a crystalline region of the crystalline polyester resin is at least 6.0 mJ/mg.

An electrostatic latent image developing toner includes toner particles each including a toner core () and a shell layer () covering a surface of the toner core (). The shell layer () contains a hydrophilic thermosetting resin and a hydrophobic thermoplastic resin. The hydrophilic thermosetting resin is a resin having at least one functional group selected from the group consisting of oxazoline groups, carbodiimide groups, and isocyanate groups. The hydrophobic thermoplastic resin is exposed at surfaces of the toner particle.

An electrostatic latent image developing toner includes a plurality of toner particles containing a binder resin. The binder resin has an amide bond and an ester bond. An area ratio of a peak originated from C&#x2550;O stretching of the amide bond to a peak originated from C&#x2550;O stretching of the ester bond is at least 0.00010 and no greater than 0.02000 in a FT-IR spectrum of the toner obtained by Fourier transform infrared spectroscopy analysis. The toner has a storage elastic modulus at 80&#xb0; C. of at least 3.5&#xd7;10Pa and no greater than 5.0&#xd7;10Pa. The toner has a storage elastic modulus at 120&#xb0; C. of at least 1.0&#xd7;10Pa and no greater than 10&#xd7;10Pa. The toner has a storage elastic modulus at 150&#xb0; C. of at least 1.0&#xd7;10Pa and no greater than 10&#xd7;10Pa.

A toner includes a plurality of toner particles each including a toner core and a shell layer covering a surface of the toner core. The toner core contains a crystalline polyester resin, a crosslinked non-crystalline polyester resin, and an uncrosslinked non-crystalline polyester resin. An endothermic energy amount &#x394;His at least 0.0 mJ/mg and no greater than 1.0 mJ/mg. The shell layer contains a resin that has a repeating unit including an oxazoline group. The toner has a glass transition point of at least 10&#xb0; C. and no greater than 40&#xb0; C. Loss tangents tan &#x3b4;and tan &#x3b4;of the toner are each at least 1.00 and no greater than 4.00. Loss tangents tan &#x3b4;and tan &#x3b4;of the toner are each at least 0.01 and no greater than 0.50.

An electrostatic latent image developing toner includes a plurality of toner particles each including a core containing a binder resin and a shell layer covering a surface of the core. The shell layer contains a copolymer of at least two vinyl compounds including a compound represented by the following formula (1). The toner contains a ring unopened oxazoline group in an amount of at least 0.10 &#x3bc;mol/g and no greater than 100 &#x3bc;mol/g. 

An electrostatic latent image developing toner includes a plurality of toner particles each including a core and a shell layer. The shell layer is disposed over a surface of the core. The shell layer is substantially formed by a resin. The shell layer has a surface including a plurality of spot regions and a sheet region that is more hydrophobic than the spot regions. The spot regions each are more chargeable than the sheet region.

An electrostatic latent image developing toner includes a plurality of toner particles each including a core containing a binder resin and a shell layer covering a surface of the core. The shell layer contains a copolymer of at least two compounds including a compound represented by formula (1) shown below. In the formula (1), Rrepresents a hydrogen atom or an optionally substituted alkyl group having a carbon number of at least 1 and no greater than 8, and Rrepresents an optionally substituted linear alkyl group having a carbon number of at least 8 and no greater than 22. 

A positively chargeable toner contains plural toner particles each containing a core, and a shell layer disposed over the core. The shell layer contains a first resin containing at least one repeating unit having an amide group, and a second resin containing at least one repeating unit having a quaternary ammonium cation. The toner attains a charge amount Qafter stirring for 3 minutes and attains a charge amount Qafter stirring for 30 minutes, and 'Q&#x2266;Q' and '20 &#x3bc;C/g&#x2266;Q' are both satisfied. Assuming that a second mixture of 100 parts by mass of the standard carrier and 10 parts by mass of the toner charged to a saturated charge amount is born on a development roller to measure a charge amount distribution, an arithmetic mean X and a standard deviation Y of the charge amount distribution satisfy &#x201c;Y/X&#x2266;3.5&#x201d;.

Positively chargeable toner

An electrostatic latent image developing toner contains a plurality of toner particles. Each of the toner particles contains, in a surface portion thereof, at least one hydrophobic salt in a state where a cation derived from a first surfactant is ionically bonded to an anion derived from a second surfactant. A ratio of a total mass of the at least one hydrophobic salt to a mass of the toner is 1 ppm or more and 5,000 ppm or less.

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Osaka, Japan

Haruhiro Nishitera