Abstract: A toner comprising a toner particle comprising a binder resin, a nonmagnetic inorganic oxide particle A, and a magnetic iron oxide particle B, wherein a softening point of a chloroform-soluble component of the toner particle is not greater than 90° C.; the nonmagnetic inorganic oxide particle A and the magnetic iron oxide particle B are internally added to the toner particle; the nonmagnetic inorganic oxide particle A comprises as its main component at least one element selected from the group consisting of Si, Mg, Al, Ti, and Sr; a proportion of the inorganic oxide particles having a long diameter of specific length is in specific range; and a value of a ratio of a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A, to a number-average particle diameter of the long diameter for the magnetic iron oxide particle B, is 5 to 30.

Abstract: A toner and a method for producing the toner, wherein; the toner comprising a toner particle comprising a polyester resin, and has a softening point of 150° C. or less; the toner particle has the polyester resin within 100 nm from a surface of the toner particle, and where a value obtained by dividing an amount of counted ions for a structure represented by following formula (A) measured from the surface of the toner particle to a depth of 100 nm by TOF-SIMS by a total amount of counted ions is taken as a standard value, one or more peaks of the standard value are present within a range of 100 nm from the surface of the toner particle, and where A(dmax) denotes a standard value at a maximum peak and A(0) denotes a standard value on the toner particle surface, formula 1.15?A(dmax)/A(0)?5.00 is satisfied.

Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image on a surface of the electrophotographic photosensitive member, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member; a conductive layer at the surface of the conductive member has a matrix and a plurality of domains dispersed in the matrix; at least a portion of the domains is exposed at the outer surface of the conductive member; the outer surface of the conductive member is constituted of at least the matrix and the domains; a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm; a volume resistivity R2 of the domains is smaller than R1; the developing unit contains the toner; and a dielectric loss tangent of the toner is at least 0.0027.

Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer at the surface of the conductive member has a matrix-domain structure, at least a portion of the domains is exposed at the outer surface of the conductive member, the outer surface of the conductive member is constituted at least of the matrix and these domains, a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm, a volume resistivity R2 of the domains is less than R1, Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy a prescribed relationship, and an onset temperature T(A) for a storage elastic modulus E? of the toner is not more than 80.0° C.

Abstract: The toner contains a toner particle having a core-shell structure including: a core containing a binder resin and a colorant; and a shell, wherein the toner contains a crystalline material, and the shell contains an amorphous thermoplastic resin; and when SP values of the crystalline material and the amorphous thermoplastic resin, which are calculated by the Fedors method, are defined as SPc (J/cm3)0.5 and SPa (J/cm3)0.5, respectively, the SPc and the SPa (J/cm3) satisfy a particular relationship, and when the toner is observed by SEM after the toner has been subjected to ruthenium staining that treats the toner in an atmosphere of RuO4 gas having 500 Pa for 15 minutes, a ratio S2 (%) of an area occupied by the crystalline material per area of the toner satisfies a particular relationship.

Abstract: A toner containing a toner particle that contains a binder resin and a crystalline material, wherein, in measurement of powder dynamic viscoelasticity of the toner, when T(A)° C. is taken as an onset temperature for a storage elastic modulus E? obtained at a ramp rate of 20° C./min, EA?(100) Pa is taken as a storage elastic modulus at 100° C. obtained at a ramp rate of 20° C./min, and T(B)° C. is taken as an onset temperature for a storage elastic modulus E? obtained at a ramp rate of 5° C./min, T(A)?T(B) is 3.0° C. or less, T(A) is from 45.0° C. to 70.0° C., and EA?(100) is from 4.0×109 Pa to 6.5×109 Pa.

Abstract: A toner comprising a toner particle including a binder resin and a magnetic body, wherein in cross-sectional observation of the toner with a transmission electron microscope, where an area percentage occupied by the magnetic body in a region of 200 nm or less from a contour of a cross section of the toner particle to a centroid of the cross section is taken as A1, and an area percentage occupied by the magnetic body in a region of from 200 nm to 400 nm from the contour of the cross section of the toner particle to the centroid of the cross section is taken as A2, the area percentage A1 is from 38% to 85%, the area percentage A2 is from 0% to 37%, and a ratio A2/A1 of the area percentage A2 to the area percentage A1 is from 0 to 0.75.

Abstract: A toner comprising a toner particle including a binder resin, wherein the toner is such that (1) when a powder dynamic viscoelasticity measurement method is used, a measurement start temperature is set to 25° C., and a ramp rate is set to 20° C./min, on a curve of a storage elastic modulus E? (Pa) where a temperature (° C.) is plotted against an abscissa and the storage elastic modulus E? is plotted against an ordinate, a temperature at a time when the E? at a start of a measurement has decreased by 50% is from 60° C. to 90° C., and (2) a load at a yield point of a displacement-load curve which is determined by a nanoindentation method and where a load (mN) is plotted against an ordinate and a displacement amount (?m) is plotted against an abscissa, is 0.80 mN or more; and a method for producing thereof.

Abstract: A toner including a toner particle including a binder resin and a crystalline material, wherein in powder dynamic viscoelasticity measurement of the toner, where an onset temperature of a storage elastic modulus E? obtained when a temperature is raised at 20° C./min is denoted by T(A)° C., and an onset temperature of a storage elastic modulus E? obtained when a temperature is raised at 5° C./min is denoted by T(B)° C., T(A)?T(B) is 3.0° C. or less, in DSC of the toner, a peak temperature of a maximum endothermic peak is from 50.0° C. to 90.0° C., and an amount of a tetrahydrofuran-insoluble component in the binder resin is from 15% by mass to 60% by mass.

Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member, a conductive layer at the surface of the conductive member has a matrix-domain structure, at least a portion of the domains is exposed at the outer surface of the conductive member, the outer surface of the conductive member is constituted at least of the matrix and these domains, a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm, a volume resistivity R2 of the domains is less than R1, Martens hardness G1 of the matrix and Martens hardness G2 of the domains satisfy a prescribed relationship, and an onset temperature T(A) for a storage elastic modulus E? of the toner is not more than 80.0° C.

Abstract: An electrophotographic apparatus having an electrophotographic photosensitive member, a charging unit, and a developing unit for forming a toner image on a surface of the electrophotographic photosensitive member, wherein the charging unit has a conductive member disposed to be contactable with the electrophotographic photosensitive member; a conductive layer at the surface of the conductive member has a matrix and a plurality of domains dispersed in the matrix; at least a portion of the domains is exposed at the outer surface of the conductive member; the outer surface of the conductive member is constituted of at least the matrix and the domains; a volume resistivity R1 of the matrix is greater than 1.00×1012 ?·cm; a volume resistivity R2 of the domains is smaller than R1; the developing unit contains the toner; and a dielectric loss tangent of the toner is at least 0.0027.

Abstract: A toner containing a toner particle that contains a binder resin and a crystalline material, wherein, in measurement of powder dynamic viscoelasticity of the toner, when T(A)° C. is taken as an onset temperature for a storage elastic modulus E? obtained at a ramp rate of 20° C./min, EA?(100) Pa is taken as a storage elastic modulus at 100° C. obtained at a ramp rate of 20° C./min, and T(B)° C. is taken as an onset temperature for a storage elastic modulus E? obtained at a ramp rate of 5° C./min, T(A)?T(B) is 3.0° C. or less, T(A) is from 45.0° C. to 70.0° C., and EA?(100) is from 4.0×109 Pa to 6.5×109 Pa.

Abstract: A toner including a toner particle including a binder resin and a crystalline material, wherein in powder dynamic viscoelasticity measurement of the toner, where an onset temperature of a storage elastic modulus E? obtained when a temperature is raised at 20° C./min is denoted by T(A)° C., and an onset temperature of a storage elastic modulus E? obtained when a temperature is raised at 5° C./min is denoted by T(B)° C., T(A)?T(B) is 3.0° C. or less, in DSC of the toner, a peak temperature of a maximum endothermic peak is from 50.0° C. to 90.0° C., and an amount of a tetrahydrofuran-insoluble component in the binder resin is from 15% by mass to 60% by mass.

Abstract: A toner comprising a toner particle including a binder resin and a magnetic body, wherein in cross-sectional observation of the toner with a transmission electron microscope, where an area percentage occupied by the magnetic body in a region of 200 nm or less from a contour of a cross section of the toner particle to a centroid of the cross section is taken as A1, and an area percentage occupied by the magnetic body in a region of from 200 nm to 400 nm from the contour of the cross section of the toner particle to the centroid of the cross section is taken as A2, the area percentage A1 is from 38% to 85%, the area percentage A2 is from 0% to 37%, and a ratio A2/A1 of the area percentage A2 to the area percentage A1 is from 0 to 0.75.

Abstract: A toner comprising a toner particle including a binder resin, wherein the toner is such that (1) when a powder dynamic viscoelasticity measurement method is used, a measurement start temperature is set to 25° C., and a ramp rate is set to 20° C./min, on a curve of a storage elastic modulus E? (Pa) where a temperature (° C.) is plotted against an abscissa and the storage elastic modulus E? is plotted against an ordinate, a temperature at a time when the E? at a start of a measurement has decreased by 50% is from 60° C. to 90° C., and (2) a load at a yield point of a displacement-load curve which is determined by a nanoindentation method and where a load (mN) is plotted against an ordinate and a displacement amount (?m) is plotted against an abscissa, is 0.80 mN or more; and a method for producing thereof.

Abstract: A toner comprising a toner particle having a binder resin and a colorant, and metal titanate fine particles, wherein the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×10?8 ?·m to 10.0×10?8 ?·m; the amount of the polyvalent metal element in the toner particle is from 0.080 ?mol/g to 20.000 ?mol/g; the metal titanate fine particles have a perovskite crystal structure; and the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.

Abstract: A toner comprising a toner particle having a binder resin and a colorant, and metal titanate fine particles, wherein the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×10?8 ?·m to 10.0×10?8 ?·m; the amount of the polyvalent metal element in the toner particle is from 0.080 ?mol/g to 20.000 ?mol/g; the metal titanate fine particles have a perovskite crystal structure; and the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.