Canon Kabushiki Kaisha

Yuu Nishimura

Kazuyoshi Akiyama

Tomohito Ozawa

Nobuyoshi Sugahara

Toru Takahashi

Koh Ishigami

Takaho Shibata

Toshiyasu Shirasuna

Hitoshi Sano

Shin Kitamura

Daisuke Tazawa

Kazunari Ooyama

Hironori Minagawa

Yuzo Tokunaga

Hironori Owaki

Daisuke Tsujimoto

Ryo Nakajima

Kazuki Murata

Nobuhiro Yoshida

Takahiro Sato

Kentaro Kamae

Tamaki Kobayashi

Takuto Moriguchi

Yusuke Miyamoto

Yukihiro Abe

Tomoyo Miyakai

Jun Ohira

Eiji Takeuchi

Kohji Takenaka

Motoya Yamada

Maki Imura

A magnetic carrier comprises a magnetic carrier core and a coating resin layer coating a surface of the magnetic carrier core. The coating resin layer contains resin A and resin B at contents of 1% to 50% by mass and 50% to 90% by mass, respectively, based on resin components of the coating resin layer. The resin A has a first partial structure and a second partial structure, while the resin B has a third partial structure and a fourth partial structure. The mass X of the resin A, the total mass Ma of the first partial structure, and the total mass Mb of the second partial structure satisfy 0.50≤(Ma+Mb)/X≤1.00 and 0.10≤a/b≤30.0, and the SP value of the first partial structure SPa1 and the SP value of the third partial structure SPb3 satisfy 0≤|SPa1−SPb3|≤10.0.

Magnetic carrier and two-component developer

A toner includes toner particles containing a binder resin, a colorant, and inorganic fine particles, in which in a depth profile of an element distribution in a depth region from the outermost surface of a particle to a depth of 500 nm the depth profile being obtained by an element analysis performed by X-ray photoelectron spectroscopy using the toner as a sample, two or more minimum points of a concentration of a carbon element in the depth region exist, a concentration of an inorganic element becomes a maximum value at a depth position corresponding to each of the minimum points, and the inorganic element is an element derived from the inorganic fine particle.

Toner

A magnetic carrier, which is suppressed from causing the loss and wear of a magnetic carrier coating resin even when used for a long time period, and achieves a stable image density and a reduction in toner scattering. In the magnetic carrier, the resin coating layer contains a resin A having a fluorine polymer moiety, the resin coating layer has an average thickness of 50 nm or more, a ratio F(x) (atomic %) of a fluorine atom detected at a position at a depth of x nm from a surface of a magnetic carrier particle by X-ray photoelectron spectroscopy satisfies formula (1) and formula (2), and when x represents an integer of 0 or more and 20 or less, F(x) satisfies formula (3):5.0≤F(0)≤15  (1)F(20)≤5.0  (2)|F(+1)−F()|≤7.5  (3).

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

A toner, comprising a toner particle comprising a binder resin and a water-soluble polyvalent metal salt, wherein a main component of the binder resin is a polyester resin having specific acid value, the water-soluble polyvalent metal salt is a chloride, nitrate or sulfate of the specific metal, the water-soluble polyvalent metal salt has a solubility in water at 25° C. of 30 to 200 g/100 mL, in a cross-sectional observation of the toner particle, a proportion of the area of domains having a concrete surface area, relative to the total area of domains derived from the water-soluble polyvalent metal salt, is 80 to 100 area %, the expression below is satisfied, where At (area %) denotes the proportion of the total area of domains and Fm (atomic %) denotes the proportion of the polyvalent metal atom relative to the atoms in the toner as detected by X-ray fluorescence analysis.0.02≤≤0.10

A toner comprising a toner particle containing a binder resin containing at least 50 mass % of a polyester resin, wherein the polyester resin contains a polyester resin A having a silicone segment, and in XPS analysis, when X is a ratio of the number of silicon atoms attributable to silicone segments relative to a total number of measured atoms, X1 is a value of the X on the toner particle surface, X2 is a value of the X at a depth of 30 nm from the surface, Z is a ratio of the number of carbon atoms attributable to ester bonds relative to a total number of measured atoms, Z1 is a value of the Z on the toner particle surface and Z2 is a value of the Z at a depth of 30 nm from the toner particle surface, X1, Z1, X2 and Z2 satisfy a specific relationship.

A toner including a toner particle comprising a binder resin and a crystalline polyester, wherein the binder resin contains a polyester having a structure represented by the following formula (1): in formula (1), Rs each independently represent hydrogen, a methyl group, or a phenyl group;A represents a polyester segment;B represents a polyester segment or any functional group selected from the group consisting of &#x2014;ROH, &#x2014;RCOOH, and &#x2014;RNHwherein Rrepresents a single bond or a Calkylene group; andthe average repeat number n is 10 to 80.

There is provided a method for controlling an electrophotographic apparatus including forming a first measurement image by performing first halftone processing on image data, forming a second measurement image by performing second halftone processing different from the first halftone processing on the image data, measuring densities of the first measurement image and the second measurement image, calculating a density difference between each of densities of the measurement images, determining whether the density difference satisfies a predetermined reference value, and applying a surface treatment on an electrophotographic photosensitive member if the density difference does not satisfy the reference value, during a non-image formation period.

Method for controlling electrophotographic apparatus

A surface layer of the electrophotographic photosensitive member has a change region in which a ratio of the number of carbon atoms with respect to the sum of the number of silicon atoms and the number of carbon atoms gradually increases toward a surface side of the electrophotographic photosensitive member from a photoconductive layer side, wherein the change region has an upper charge injection prohibiting portion containing a Group 13 atom, and a surface-side portion which is positioned closer to the surface side of the electrophotographic photosensitive member than the upper charge injection prohibiting portion and does not contain the Group 13 atom, and the distribution of the Group 13 atom in a boundary portion between the surface-side portion and the upper charge injection prohibiting portion is precipitous.

Electrophotographic photosensitive member, method for manufacturing the same, and electrophotographic apparatus

In an electrophotographic photosensitive member having a photoconductive layer and, provided on the photoconductive layer, a surface layer constituted of a hydrogenated amorphous silicon carbide, the ratio of the number of atoms of carbon atoms (C) to the sum of the number of atoms of silicon atoms (Si) and number of atoms of carbon atoms (C), C/(Si+C), in the surface layer is from 0.61 or more to 0.75 or less, and the sum of atom density of the silicon atoms and atom density of the carbon atoms in the surface layer is 6.60&#xd7;10atom/cmor more.

Electrophotographic photosensitive member and electrophotographic apparatus

An electrophotographic apparatus has an electrophotographic photosensitive member having a surface layer of an amorphous silicon carbide. The ratio of the atom density (C) of carbon atoms to the sum of the atom density (Si) of silicon atoms and the atom density (C) of carbon atoms, C/(Si+C), in the surface layer is set larger from one end portion toward the other end portion of the electrophotographic photosensitive member in the direction of rotational axis thereof, and is from 0.61 or more to 0.75 or less in the entire region of the electrophotographic photosensitive member in the direction of rotational axis thereof. The electrophotographic apparatus has an air current generator which draws out air from the side of the one end portion toward the side of the other end portion.

Electrophotographic apparatus having an electrophotgraphic photosensitive member with an amorphous silicon carbide surface layer

An electrophotographic photosensitive member is configured such that the average value Hx_ave of the content of hydrogen atoms in a central portion area of a photoconductive layer in a cylindrically axial direction thereof, the content Hx of the hydrogen atoms at an arbitrary point in the central portion area, the average value Hy_ave of the content of the hydrogen atoms in an end area of the photoconductive layer in the cylindrically axial direction thereof, and the content Hy of the hydrogen atoms at an arbitrary point in the end area satisfy 10&#x2266;Hx_ave&#x2266;30, Hx&#x3c;Hy, |Hx_ave&#x2212;Hx|&#x2266;5, and 2&#x2266;Hy_ave&#x2212;Hx_ave&#x2266;12.

An electrophotographic photosensitive member includes a photoconductive layer, an intermediate layer, and a surface layer. When Si+C atom density in the surface layer is represented by D&#xd7;10atoms/cm, the Dis 6.60 or more, and when the maximal value of H/(Si+H) in a distribution of hydrogen quantity in the photoconductive layer in a layer thickness direction is represented by H, the average value of the H/(Si+H) in the second photoconductive region is represented by H, the Dand the Hsatisfy the following expression (1) and the Dand the Hsatisfy the following expression (2).&#x2267;0.07&#xd7;&#x2212;0.38&#x2003;&#x2003;Expression (1)&#x2266;0.04&#xd7;+0.60&#x2003;&#x2003;Expression (2)

The present invention provides an electrophotographic photosensitive member including a photoconductive layer, an intermediate layer made of hydrogenated amorphous silicon carbide on the photoconductive layer, and a surface layer made of hydrogenated amorphous silicon carbide on the intermediate layer, wherein a ratio (C/(Si+C); C2) in the surface layer is 0.61 to 0.75, and a sum of atom density of silicon and carbon is 6.60&#xd7;10atoms/cmor more, a ratio (C/(Si+C); C1) and a sum (D1) of atom density of silicon and carbon in the intermediate layer increase continuously from the photoconductive layer toward the surface layer without exceeding C2 and D2, and the intermediate layer has a continuous region in which C1 is 0.25 to C2 while D1 is 5.50&#xd7;10to 6.45&#xd7;10atoms/cm, the region being 150 nm or larger in a layer thickness direction, and an electrophotographic apparatus equipped therewith.

An electrophotographic photosensitive member includes a photoconductive layer and, provided on the photoconductive layer, a surface layer containing a hydrogenated amorphous silicon carbide. A ratio of the number of carbon atoms (C) to the sum of the number of silicon atoms (Si) and number of carbon atoms (C), C/(Si+C), in the surface layer is from 0.61 or more to 0.75 or less, and the sum of atom density of the silicon atoms and atom density of the carbon atoms in the surface layer is 6.60&#xd7;10atom/cmor more.

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Suntou-gun, Japan

Yuu Nishimura