Abstract: A toner comprising a toner particle containing a binder resin and an inorganic fine particle, wherein the binder resin contains a crystalline resin, the crystalline resin has a first monomer unit represented by the following formula (1), the inorganic fine particle is at least one inorganic fine particle selected from the group consisting of a particle containing CaCO3, a particle containing BaSO4, a particle containing Mg3Si4O10(OH)2, and a particle containing Al2Si2O5(OH)4, the inorganic fine particle is treated with a fatty acid, and a content B of the inorganic fine particle in the toner particle is 1.0 mass % or more to 15.0 mass % or less, wherein RZ1 represents a hydrogen atom or a methyl group, and R1 represents an alkyl group having 18 to 36 carbon atoms.

Abstract: A toner comprising a toner particle comprising a binder resin, wherein the binder resin comprises a first resin and a second resin, the first resin is a crystalline resin, the second resin is an amorphous resin, and in observations of cross sections of 100 toner particles using a transmission electron microscope, (i) when an area ratio A (area %) denotes a ratio of an area occupied by the first resin in each of cross sections of the toner particles, an average value of the area ratio A is 30 to 75 area %, and (ii) when X denotes the number of cross sections of the toner particle for which the area ratio A is 90 area % or more and Z denotes the total number of cross sections of observed toner particles, then a value of X/Z is 0.15 or more.

Abstract: A toner comprising a toner particle comprising a binder resin, wherein the binder resin comprises a first resin and a second resin, the first resin is a crystalline resin, the second resin is an amorphous resin, in an observation of a cross section of the toner particle with a transmission electron microscope, a matrix-domain structure composed of a matrix comprising the first resin and domains comprising the second resin is present, an area ratio occupied by the matrix in a total area of the matrix and the domains is from 35 area % to 70 area %, a [hydrocarbon group index (Ge)]/[hydrocarbon group index (DIA)] after washing the toner with hexane is 1.10 or more.

Abstract: A toner comprising a toner particle comprising a binder resin and a release agent, wherein the binder resin comprises a first resin and a second resin; the first resin is a crystalline resin having a melting point Tp of 50° C. to 90° C.; the second resin is an amorphous resin; in a cross section of the toner particle observed by a transmission electron microscope, the cross section of the toner particle has a matrix-domain structure composed of a matrix comprising the first resin and domains comprising the second resin; an area ratio of the matrix comprising the first resin in a total area of the cross section of the toner particle is 35 to 70 area %; and where a longest direction of each of the domains is taken as a longitudinal direction, a standard deviation of an angle of the longitudinal direction of the domains is 25° or less.

Abstract: An external additive for toner comprising: a fine particle A containing, as a binder component, an organosilicon compound having a siloxane bond; and a fine particle B that is present on a surface of the fine particle A in a state of being at least partially embedded in the surface of the fine particle A, wherein the external additive for toner (i) has a number-average particle diameter of a primary particle of 0.03 ?m or more and 0.30 ?m or less, and (ii) has a Young's modulus of 10 GPa or more and 30 GPa or less, wherein content ratios, on a number basis, of the following unit (a), unit (b), and unit (c) in the fine particle A based on all silicon atoms present in the fine particle A satisfy the following expressions (1) and (2). (a)+(b)+(c)?0.80??(1) (b)+(c)?0.

Abstract: The external additive for toner includes an external additive particle containing: a fine particle A; and a plurality of fine particles B that are each present so as to partially protrude from a surface of the fine particle A, wherein the fine particle A (i) is a particle of an organosilicon compound having a siloxane bond, (ii) has a number-average particle diameter of 0.03 ?m or more and 0.30 ?m or less, and (iii) has an average circularity of 0.90 or more, wherein, when the number-average particle diameter of the fine particle A is represented by DA, and a number-average particle diameter of the plurality of fine particles B is represented by DB, DB/DA is 0.10 or more and 0.63 or less.

Abstract: The external additive for toner includes an external additive particle containing: a base particle A; and a plurality of convex forming particles B each configured to form a convex portion on a surface of the base particle A. The base particle A and the convex forming particles B are particles each containing a silicon compound having a siloxane bond, and a chemical bond is formed between the base particle A and each of the convex forming particles B. The base particle A and the convex forming particles B each have a total content of the following unit (a), unit (b), and unit (c) of 80 mass % or more and 100 mass % or less: where R1 and R2 each represent an alkyl group having 1 or more and 6 or less carbon atoms.

Abstract: Provided is a toner comprising: a toner particle containing a binder resin; and an organic silicon polymer particle on a surface of the toner particle, wherein the binder resin contains a crystalline resin, and when the toner particle is pelletized and a Young's modulus of the toner measured in a micro compression test at 25° C. is represented by TE (MPa) and when one organic silicon polymer particle is separated from the toner and a Young's modulus of the one organic silicon polymer particle measured in a micro compression test at 25° C. is represented by SiE (MPa), TE and SiE satisfies 800?TE?2500 and 1.5?SiE/TE?10.0.

Abstract: A toner comprising a toner particle containing a binder resin and an inorganic fine particle, wherein the binder resin contains a crystalline resin, the crystalline resin has a first monomer unit represented by the following formula (1), the inorganic fine particle is at least one inorganic fine particle selected from the group consisting of a particle containing CaCO3, a particle containing BaSO4, a particle containing Mg3Si4O10(OH)2, and a particle containing Al2Si2O5(OH)4, the inorganic fine particle is treated with a fatty acid, and a content B of the inorganic fine particle in the toner particle is 1.0 mass % or more to 15.0 mass % or less, wherein RZ1 represents a hydrogen atom or a methyl group, and R1 represents an alkyl group having 18 to 36 carbon atoms.

Abstract: A toner comprising a toner particle comprising a binder resin, wherein the binder resin comprises a first resin and a second resin, the first resin is a crystalline resin, the second resin is an amorphous resin, and in observations of cross sections of 100 toner particles using a transmission electron microscope, (i) when an area ratio A (area %) denotes a ratio of an area occupied by the first resin in each of cross sections of the toner particles, an average value of the area ratio A is 30 to 75 area %, and (ii) when X denotes the number of cross sections of the toner particle for which the area ratio A is 90 area % or more and Z denotes the total number of cross sections of observed toner particles, then a value of X/Z is 0.15 or more.

Abstract: A toner comprising a toner particle comprising a binder resin, wherein the binder resin comprises a first resin and a second resin, the first resin is a crystalline resin, the second resin is an amorphous resin, in an observation of a cross section of the toner particle with a transmission electron microscope, a matrix-domain structure composed of a matrix comprising the first resin and domains comprising the second resin is present, an area ratio occupied by the matrix in a total area of the matrix and the domains is from 35 area % to 70 area %, a [hydrocarbon group index (Ge)]/[hydrocarbon group index (DIA)] after washing the toner with hexane is 1.10 or more.

Abstract: A toner comprising a toner particle comprising a binder resin and a release agent, wherein the binder resin comprises a first resin and a second resin; the first resin is a crystalline resin having a melting point Tp of 50° C. to 90° C.; the second resin is an amorphous resin; in a cross section of the toner particle observed by a transmission electron microscope, the cross section of the toner particle has a matrix-domain structure composed of a matrix comprising the first resin and domains comprising the second resin; an area ratio of the matrix comprising the first resin in a total area of the cross section of the toner particle is 35 to 70 area %; and where a longest direction of each of the domains is taken as a longitudinal direction, a standard deviation of an angle of the longitudinal direction of the domains is 25° or less.

Abstract: To provide a molecular structure generation method and a non-transitory computer-readable medium storing a program capable of generating various molecular structures while satisfying desired property values so as not to be localized around a specific molecular structure. A molecular structure generation method according to the present invention includes: a selection step of classifying a plurality of initial molecules prepared in advance into clusters based on a feature amount and selecting a starting molecule having a maximum confidence limit value from each of the classified clusters. The method further includes an evolutionary development step of evolving each of the starting molecules. Further the selection step and the evolutionary development step are repeatedly executed for all molecules including the initial molecules and the evolved starting molecules to generate a new molecular structure.

Abstract: 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.

Abstract: 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.

Abstract: The present invention provides an electrophotographic photosensitive member which has a substrate, a photoconductive layer and a surface layer formed from hydrogenated amorphous silicon carbide in this order. The average value of the carbon content (C/(C+Si)) of the surface layer formed from the hydrogenated amorphous silicon carbide is set at 0.90 or more and less than 1.00, and the average value of the hydrogen content (H/(H+C+Si)) is set at 0.40 or less; and when the average value of the ratios of the sum of a Si—O bond and an O—Si—O bond in the outermost surface region that constitutes a range within a depth of 5 nm or less from the outermost surface of the surface layer is represented by a, and an average value of the silicon content (Si/(C+Si)) is represented by b, 0.015?a*b?0.090 holds.

Abstract: An average value of a hydrogen content ratio of a surface layer made of hydrogenated amorphous carbon is set to be 0.40 or less and a maximum value of an sp2 bonding ratio in an outermost surface region of the surface layer made of the hydrogenated amorphous carbon is set to be 0.50 or less.

Abstract: An average value of a hydrogen content ratio of a surface layer made of hydrogenated amorphous carbon is set to be 0.40 or less and a maximum value of an sp2 bonding ratio in an outermost surface region of the surface layer made of the hydrogenated amorphous carbon is set to be 0.50 or less.

Abstract: The present invention provides an electrophotographic photosensitive member which has a substrate, a photoconductive layer and a surface layer formed from hydrogenated amorphous silicon carbide in this order. The average value of the carbon content (C/(C+Si)) of the surface layer formed from the hydrogenated amorphous silicon carbide is set at 0.90 or more and less than 1.00, and the average value of the hydrogen content (H/(H+C+Si)) is set at 0.40 or less; and when the average value of the ratios of the sum of a Si—O bond and an O—Si—O bond in the outermost surface region that constitutes a range within a depth of 5 nm or less from the outermost surface of the surface layer is represented by a, and an average value of the silicon content (Si/(C+Si)) is represented by b, 0.015?a*b?0.090 holds.

Abstract: A method for manufacturing an electrophotographic photosensitive member using plasma CVD includes steps of placing a cylindrical base member in a reactor which can be evacuated, the reactor having an electrode therein, so as to be spaced apart from the electrode, introducing a raw material gas for deposited film formation into the reactor, and applying an alternating voltage of a rectangular wave having a frequency in the range of 3 kHz to 300 kHz between the electrode and the cylindrical base member so that a potential at one of the electrode and the cylindrical base member with respect to a potential at the other becomes alternately positive and negative, to decompose the raw material gas, and forming a deposited film on the cylindrical base member. The magnitude of the potential difference between the electrode and the cylindrical base member is selectively controlled.