Canon Kabushiki Kaisha

Shintaro Kawaguchi

Masamichi Sato

Akira Sugiyama

Masatake Tanaka

Taiji Katsura

Kenichi Nakayama

Shota Amano

Takashi Kenmoku

Yuhei Terui

Naoya Isono

Katsuyuki Nonaka

Yasuhiro Hashimoto

Shohei Tsuda

Ryo Sugiyama

Koji Abe

Takeshi Kaburagi

Naotaka Ikeda

Tatsuya Saeki

Tomoya Uesugi

A toner comprising: a toner particle comprising a binder resin and boric acid; and an external additive A having a primary particle major diameter of 80 to 200 nm, wherein in ATR-IR analysis of the toner particle in an ATR method using germanium as an ATR crystal, a peak corresponding to boric acid is detected, the average value of a shape factor SF-1 of the external additive A is 105 to 250, and the average value of a shape factor SF-2 of the external additive A is 102 to 250.

Toner and method for producing toner

A process cartridge includes a toner, a regulating member, and a developing roller including a conductive substrate, an elastic layer, and a surface layer which includes a binder resin, a first resin particle having an elastic coefficient of 100 to 10,000 MPa, and a second resin particle having an elastic coefficient of 2 to 50 MPa and in which the outer surface has a first protruded portion and a second protruded portion 5.0 μm or more lower than the first protruded portion and has an average maximum height of 6 to 18 μm. The toner includes a toner particle and an external additive A that is a silica particle having a major diameter of 40 to 400 nm, a surface coverage of the toner particle by the external additive A is 3.0% or more, and a dispersion degree evaluation index D of the external additive A is 2.0 or less.

Process cartridge

A process cartridge includes a photosensitive member, a toner, and a developing roller, a surface layer of the photosensitive member has a Martens hardness of 245 to 300 N/mm, the developing roller has a single-layered surface layer containing a substrate and a binder resin; when an elastic modulus of the binder resin in a first region is E1, and an elastic modulus of the binder resin in a second region is E2, E1≥200 MPa and 10 MPa≤E2≤150 MPa are satisfied; the elastic modulus in the second region continuously decreases from that in the first region; the toner comprises a toner particle and an external additive A; the external additive A is a silica particle having a major diameter of 40 to 400 nm; and a coverage of the external additive A with respect to surface of the toner particle is 5.0% or more.

A toner comprising a toner particle that comprises a core particle comprising a binder resin and a surface layer comprising inorganic fine particles and an organosilicon polymer, wherein the organosilicon polymer has T3 structure represented by R—Si(O), inSi-NMR measurement of THF insoluble-matter of the toner particle, a proportion of a peak area assigned to the T3 structure relative to a total peak area for the organosilicon polymer is at least 5.0%, and in observation of a cross section of the toner particle using TEM, the toner has a prescribed surface layer thickness, a prescribed number of inorganic fine particles in contact with the core particle in the surface layer, and a prescribed number of inorganic fine particles present in the core particle and not in contact with the surface layer.

Toner

A toner comprising: a toner particle; and an external additive, wherein the external additive includes spherical silica particles and hydrotalcite particles, a number average particle diameter Da of the spherical silica particles is from 10 nm to 40 nm, a circularity of the spherical silica particles is at least 0.80, and the toner satisfies formula (1) below:{&#xd7;(1&#x2212;/100)}/{&#xd7;(1&#x2212;/100)}&#x2265;0.050&#x2003;&#x2003;(1)wherein Ga: a content of the spherical silica particles with respect to 100 parts by mass of the toner particle; Gb: a content of the hydrotalcite particles with respect to 100 parts by mass of the toner particle; Ka: a fixing ratio (%) of the spherical silica particles on a surface of the toner particle; and Kb: a fixing ratio (%) of the hydrotalcite particles on the surface of the toner particle.

A toner comprising: a toner particle that includes a binder resin, and an external additive, wherein the toner particle includes a polyester resin on the surface; the toner particle includes a polyvalent metal element; where an electrical resistivity of the polyvalent metal element at 20&#xb0; C. is denoted by A &#x3a9;&#xb7;m, and an amount of the polyvalent metal element in the toner particle is denoted by B &#x3bc;mol/g, a following relationship is satisfied:0.025&#xd7;10&#x2264;(1/)&#xd7;&#x2264;4.500&#xd7;10;

A toner has a toner particle that contains a binder resin and a charge control resin, wherein the charge control resin is a polymer that contains a unit A and a unit B, the unit A is a unit derived from 2-acrylamido-2-methylpropanesulfonic acid, the unit B is a unit derived from an electron donor compound that has a polymerizable unsaturated group, and a molar ratio between the unit A and the unit B is from 1.0 to 10.0.

A toner having good development durability, storage stability, environmental stability, and low-temperature fixability is provided. The toner contains toner particles each including a surface layer that contains an organic silicon polymer. The organic silicon polymer contains a unit having a specific structure. The average thickness Dav. of the surface layers is a specific value and the silicon concentration determined by ESCA is 2.5% or more. The toner has a shape factor SF-2 of 140 or more and 260 or less and an average circularity of 0.970 or more and 0.990 or less.

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Yokohama, Japan

Shintaro Kawaguchi