Canon Kabushiki Kaisha

Ryuji Murayama

Junichi Tamura

Hayato Ida

Takaho Shibata

Takashi Hirasa

Daisuke Yamashita

Yuya Chimoto

Kentaro Kamae

Tomoyo Miyakai

Hironori Minagawa

Kouichirou Ochi

Yuto Onozaki

Nobuhiro Yoshida

Masashi Hirose

Yasuaki Murai

Kazuyuki Sato

Kei Inoue

Masaharu Miura

Yuichi Mizo

Kenta Mitsuiki

Akemi Watanabe

Megumi Shino

Soichiro Kawakami

Koh Ishigami

Wakiko Katsumata

A magnetic carrier including: a magnetic core; and a coating resin that coats a surface of the magnetic core, wherein the resin coating layer has a thickness of 50 nm or more, a coating resin, which forms the resin coating layer, contains a resin S having an organosilicon polymer moiety, and when a surface and a position at a depth of 20 nm from the surface of the magnetic carrier are analyzed by X-ray photoelectron spectroscopy, an amount of silicon element as determined by the analysis has a ratio within a specific range at respective positions.

Magnetic carrier, two-component developer, and replenishment developer

A magnetic carrier includes a magnetic core and a coating resin that covers a surface of the magnetic core. The coating resin includes a resin A and a resin B. A content of the resin A is 1 to 50% by mass, and a content of the resin B is 50 to 99% by mass, with respect to the coating resin. The resin A has a particular unit Y1 and a particular unit Y2, and the resin B contains 0.1% by mass or less of the particular unit Y2. When a mass of the resin A is represented by X, a mass of the unit Y1 is represented by Ma, and a mass of the unit Y2 is represented by Mb, 0.90≤(Ma+Mb)/X≤1.00 and 1.00≤Ma/Mb≤30.0 are satisfied, and also 0≤|SPa−SPb|≤2.0 is satisfied.

A magnetic carrier including a magnetic core and a coating resin configured to coat the surface of the magnetic core. The coating resin contains a graft resin A and a graft resin B. The coating resin (i) contains 1.0 mass % or more and 50.0 mass % or less of the graft resin A, and (ii) contains 50.0 mass % or more and 99.0 mass % or less of the graft resin B. The graft resin A has a unit Y1 represented by formula (1) and a unit Y2 represented by formula (2). The graft resin B (i) is a comb-shaped polymer having, as a branch, at least one moiety selected from, for example, a styrene-based polymer moiety and a (meth)acrylate-based polymer moiety, and (ii) contains the polysiloxane structure moiety at a content of 0.1 mass % or less.

Magnetic carrier, two-component developer, and developer for replenishment

A toner having a toner particle containing a binder resin and a styrene-acrylic resin, the toner being characterized in that the styrene-acrylic resin is a graft polymer having an aliphatic hydrocarbon compound segment and a styrene-acrylic segment, the styrene-acrylic segment has a specific monomer unit, the melting point of the styrene-acrylic segment is from 30&#xb0; C. to 80&#xb0; C., and when the toner is measured using a FT-IR ATR method, the intensity assigned to the styrene-acrylic resin and the intensity assigned to the binder resin satisfy a specific relationship.

Toner

A toner comprises a toner particle including a binder resin, and inorganic fine particles A and silica particles B, wherein the inorganic fine particle A has a rectangular parallelepiped shape; an amount of the inorganic fine particles A is 0.3 to 3.0 mass parts per 100 mass parts of the toner particles; a number average particle diameter of the silica particles B is 80 to 200 nm; a fixing ratio of the inorganic fine particle A is 25% to 70%; where a separation amount of the inorganic fine particles A is denoted by YA (mg), and a separation amount of the silica particles is denoted by YB (mg), YA is 3.00 to 18.0, YA and YB satisfy the following formula,&#x3e;0.75, and a surface potential difference C in a rubbing test using the inorganic fine particle A and the binder resin is &#x2212;70 V to +70 V.

Toner and image forming method

A toner comprises a toner particle and an external additive, the toner satisfies a certain relationship with regard to &#x3c3;l (C/m) and &#x3c3;s (C/m). The toner is divided into two groups i.e. a first group and a second group with inertial classifier, the first group including a larger size of the toner particles, and the second group including a smaller size of the toner particles, and the number of the toner particles in the first group being substantially equal to the number of the toner particles in the second group. Then, al (C/m) represents an absolute value of average surface charge density of the toner included in the first group, and &#x3c3;s (C/m) represents an absolute value of average surface charge density of the toner included in the second group.

A toner includes a toner particle containing a binder resin and a silica fine particle A on a surface of the toner particle, wherein D50 on a number basis of the toner is 3.0 to 6.0 the silica fine particle A is a particle having a particle diameter of 80 to 500 nm, the particle diameter being confirmable by observing the toner with a SEM, and when the average coverage with the silica fine particle A determined by image analysis of a particle group of a small particle diameter side of the toner with a SEM is set to Sand the average coverage with the silica fine particle A determined by image analysis of a particle group of a large particle diameter side of the toner with a scanning electron microscope is set to S, Sis 20 to 70 area %, Sand Ssatisfy S/S&#x2264;0.80.

A toner comprising: a toner particle that contains a resin component and a silicone compound, wherein the resin component contains at least 50 mass % of olefin resin; a content of the silicone compound is from 1 mass part to 42 mass parts per 100 mass parts of the resin component; a weight-average molecular weight of the silicone compound as measured by GPC is from 1,000 to 25,000; and a content, in a molecular weight distribution of the silicone compound as measured by GPC, of a component having a weight-average molecular weight of not more than 500 is not more than 0.05 mass % of the silicone compound.

A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin copolymer including ester group having specific structures Y1 and Y2 and an olefin copolymer including acid group having an acid value of from 50 mg KOH/g to 300 mg KOH/g, the amount of the olefin copolymer including ester group is 50% by mass or more, the toner particle has a surface layer including the olefin copolymer including acid group which has formed a salt with a metal, the metal is at least one metal selected from the group consisting of Mg, Ca, Sr, Al, and Zn, and the total amount of the metal in the toner is from 25 ppm to 500 ppm.

Toner and method for producing toner

A toner including a toner particle having a core-shell structure that has a core formed from a resin 1 and a shell formed from a resin 2 on the surface of the core, wherein the resin 1 contains more than 50 mass % of an ester group-containing olefin-based copolymer, the ester group-containing olefin-based copolymer has a monomer unit Y1 represented by formula (1) below, and at least one type of monomer unit Y2 selected from the group consisting of monomer units represented by formula (2) and formula (3) below, the ester group concentration in the ester group-containing olefin-based copolymer is from 2 mass % to 18 mass %, and the resin 2 is an amorphous resin having a Tg value of from 50&#xb0; C. to 70&#xb0; C. 

A toner includes a toner particle containing a resin component containing an olefin copolymer, wherein the olefin copolymer includes a specific monomer unit Y1 and a specific monomer unit Y2, and the content of the olefin copolymer in the resin component is more than 50 mass % based on the total mass of the resin component, and the olefin copolymer has a melting point of 80&#xb0; C. or more and 150&#xb0; C. or less.

Toner and method of producing toner

A toner comprising a toner particle that contains a hybrid resin A and a crystalline polyester resin B, wherein the hybrid resin A has a polyester segment, and a polypropylene glycol segment that has a number-average molecular weight of at least 300, the polyester segment has a structure derived from a condensation reaction between a dicarboxylic acid and a diol, and has an aromatic ring in at least one of the dicarboxylic acid and the diol, and the following condition is satisfied:||&#x3c;1where, SPh is SP value of the polyester segment of the hybrid resin A, SPc is SP value of the crystalline polyester resin B, and SPp is SP value of the polypropylene glycol segment of the hybrid resin A.

A method for producing a toner includes a step (1) of forming resin microparticles in an aqueous medium in the presence of a surfactant, a step (2) of aggregating the resin microparticles to form aggregated particles, and a step (3) of heating and the aggregated particles and allowing the aggregated particles to coalesce to form toner particles, in which a resin component in the resin microparticles contains an olefinic copolymer and resin A, the resin A has an acid value of 1 mgKOH/g or more and 50 mgKOH/g or less, the resin A has a SP value of 19.0 (J/cm)or more and 21.0 (J/cm)or less, and the resin component has an olefinic copolymer content of 50% by mass or more with respect to the total mass of the resin component.

Method for producing toner

A toner including: a binder resin containing an ethylene-vinyl acetate copolymer; a polysiloxane derivative A represented by structural formula 1; and a polysiloxane derivative B represented by structural formula 2: (in structural formula 1, Rto Reach independently represent a methyl group or a phenyl group, and l, m and n each independently represent an integer of at least 1) (in structural formula 2, at least one of Rto Ris an organic group having a Calkyl group, a Calkoxy group, an acrylic group, an amino group, a methacrylic group or a carboxyl group, the remaining groups among Rto Reach independently represent a methyl group or a phenyl group, and p, q and r each independently represent an integer of at least 1).

A toner comprising a toner particle including a resin component, wherein the resin component includes an olefin resin and an olefin copolymer including a hydroxyl group, the olefin resin has a specific monomer unit Y1, the olefin copolymer including a hydroxyl group has a specific monomer unit Z1 and Z2, a hydroxyl value of the olefin resin is not more than 10 mg KOH/g, a hydroxyl value of the olefin copolymer including a hydroxyl group is at least 20 mg KOH/g and not more than 250 mg KOH/g, and a content of the olefin resin in the resin component is more than 50 mass % with respect to a total mass of the resin component.

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Nagareyama, Japan

Ryuji Murayama