Kyocera Document Solutions Inc.

Mita Industrial Co., Ltd.

Masami Tsujihiro

Ryotaro Komada

Ryota Kobayashi

Jun Hioki

Yoshio Ozawa

Nobuhiro Hirano

Yusuke Washino

Haruhiro Nishitera

Hiroshi Shimoyama

Toshiro Tokuno

Hideharu Hori

Tatsuo Imafuku

Toshiro Okae

Hideki Ohta

Naruo Yabe

Toru Takatsuna

Hidenori Asada

Ken Maetani

Masayoshi Okubo

Toshiaki Akiyama

Takuya Kadota

Akemi Uchizono

A magnetic toner includes toner particles. The toner particles each include a toner mother particle. The toner mother particle includes a polyester resin domain, a vinyl resin domain, and a magnetic powder. A vinyl resin constituting the vinyl resin domain includes a repeating unit having a non-ring-opened oxazoline group. An area rate of an area in which the vinyl resin domain is exposed in a surface area of the toner mother particle is at least 0.02% and no greater than 1.00%.

Magnetic toner

A toner includes toner particles. The toner particles each include a toner mother particle containing a binder resin and a releasing agent. The binder resin includes a polyester resin and a vinyl resin. The vinyl resin includes a specific vinyl unit. A relationship 1.30&#x2264;Wabs/Wps&#x2264;2.00 is satisfied where Wabs represents an absolute molecular weight at a largest peak on an absolute molecular weight distribution curve of the binder resin as measured by size-exclusion chromatography using a multi-angle laser light scattering detector, and Wps represents a relative molecular weight at a largest peak on a relative molecular weight distribution curve of the binder resin in terms of polystyrene as measured by size-exclusion chromatography using a differential refractive index detector.

Toner

A toner includes toner particles. The toner particles each include a toner mother particle. The toner mother particles contain a binder resin and a magnetic powder. The binder resin includes a polyester resin, a vinyl resin, and a block polymer. The block polymer includes a polyester portion, a vinyl polymer portion, and a linker that links the polyester portion and the vinyl polymer portion. The linker is derived from a specific compound having a vinyl group and at least one of a carboxy group and an alcoholic hydroxyl group. The magnetic powder has an octahedral structure.

A positively chargeable toner includes a plurality of toner particles. Each of the toner particles includes a toner mother particle and an external additive adhering to a surface of the toner mother particle. The external additive includes a plurality of resin particles. Each of the resin particles has a resin mother particle and a coat layer covering at least a portion of a surface of the resin mother particle. The coat layer contains a specific vinyl resin.

Positively chargeable 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

A toner contains a plurality of toner particles each including a core and a shell layer disposed over a surface of the core. The core contains a binder resin. The shell layer is substantially formed from a resin having at least one repeating unit including an alcoholic hydroxyl group (specific examples include a repeating unit derived from 2-hydroxyethyl acrylate, 2-hydroxy propyl acrylate, 2-hydroxyethyl methacrylate, and 2-hydroxy propyl methacrylate). A ratio of the repeating unit including the alcoholic hydroxyl group relative to all repeating units in the resin substantially forming the shell layer is at least 0.1% by mass and no greater than 20% by mass.

An electrostatic latent image developing toner includes toner particles. Each of the toner particles includes a toner mother particle and an external additive. The toner mother particle contains a binder resin. The external additive includes external additive particles adhering to a surface of the toner mother particle. Each of the external additive particles includes a titanium oxide particle and resin particles adhering to a surface of the titanium oxide particle.

Electrostatic latent image developing toner and image forming apparatus

Toner particles each include a toner core, a shell layer covering a surface of the toner core, and a plurality of wax particles. The toner core contains a binder resin and does not contain a wax. The wax particles are each located on a surface of the shell layer. The toner core and each of the wax particles are bonded together through covalent bonds within the shell layer. The covalent bonds include a first amide bond and a second amide bond. The shell layer contains a vinyl resin. The vinyl resin includes a constitutional unit (1-1), a constitutional unit (1-2), and a constitutional unit (1-3). An amide bond included in the constitutional unit (1-1) is the first amide bond. An amide bond included in the constitutional unit (1-2) is the second amide bond. 

An electrostatic latent image developing toner includes toner particles each including a toner core and a shell layer. The shell layer includes first and second domains. The first domain includes a first copolymer of a first main monomer having a mole fraction of at least 20 mol % and one or more first additional monomers each having a mole fraction of less than 20 mol %. The second domain includes a second copolymer of a second main monomer having a mole fraction of at least 20 mol % and one or more second additional monomers each having a mole fraction of less than 20 mol %. A difference in polymer SP value between the first and second main monomers is at least 0.5 and no greater than 5.0. The first and second additional monomers each include one or more common monomers having a homopolymerization glass transition point of no greater than &#x2212;20&#xb0; C.

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.

A toner includes toner particles. The toner particles each include a toner core, silica particles located on a surface of the toner core, and a shell layer disposed over the surface of the toner core on which the silica particles are located. For at least 80% by number of the toner particles, along at least 80% of a circumferential length of a cross-section of the toner particle when the cross-section is analyzed by EELS, the shell layer has a thickness of at least 5 nm and satisfies a condition that a ratio of an intensity INc relative to an intensity INs is at least 0.0 and no greater than 0.2. The intensity INs indicates intensity of an N&#x2014;K shell absorption-edge originating from nitrogen atoms in the shell layer. The intensity INc indicates intensity of an N&#x2014;K shell absorption-edge originating from nitrogen atoms in the toner core.

A toner includes a plurality of toner particles each including a toner core and a shell layer disposed over the surface of the toner core. The shell layer includes a thermosetting portion substantially composed of a water-insoluble thermosetting resin and a thermoplastic portion substantially composed of a water-insoluble thermoplastic resin. At least a part of the thermoplastic portion has a shape of a film with projections and recesses and is located on the surface of the toner core. At least a part of the thermosetting portion is located on the thermoplastic portion. The part of the thermosetting portion located on the thermoplastic portion has a shape of a film along the shape of the thermoplastic portion.

An electrostatic latent image developing toner includes toner particles that each include a toner core and a shell layer disposed over a surface of the toner core. The shell layer contains a hydrophobic thermoplastic resin and a hydrophilic thermosetting resin. The hydrophobic thermoplastic resin is contained in an amount of no less than 0.2% by mass and no greater than 4.7% by mass relative to mass of the toner particles. The hydrophilic thermosetting resin is contained in an amount of no less than 0.01% by mass and no greater than 0.71% by mass relative to mass of the toner particles. The hydrophobic thermoplastic resin is exposed at a surface of each of the toner particles.

An electrostatic latent image developing toner includes toner particles that each include a toner core and a shell layer disposed over a surface of the toner core. The shell layer contains a first shell resin and a second shell resin. The first shell resin is a hydrophilic thermoplastic resin, a hydrophobic thermoplastic resin, or a hydrophobic thermosetting resin. The second shell resin is a hydrophilic thermosetting resin. The first shell resin includes a repeating unit having an alcoholic hydroxyl group.

For at least 80% of toner particles in a toner, along at least 80% of circumferential length of a toner particle cross-section, a shell layer has a thickness of at least 5 nm and satisfies a condition that a ratio of an intensity INc relative to an intensity INs is no greater than 0.2. For at least 80% of the toner particles in the toner, along at least 80% of the circumferential length of the toner particle cross-section, the shell layer has a thickness of at least 5 nm and satisfies a condition that a ratio of an intensity ISc relative to an intensity ISs is no greater than 0.2.

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Osaka, Japan

Masami Tsujihiro