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 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 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 magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein a storage elastic modulus E?(40) [Pa] at 40° C. and a storage elastic modulus E?(85) [Pa] at 85° C., which are obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, satisfy the following formulas (1) to (3). E?(40)?6.0×109??(1) E?(85)?5.

Abstract: A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein the dielectric loss tangent at 100 kHz is 1.0×10?2 or more, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 ?m in cross-sectional observation of the magnetic toner particle using a transmission electron microscope TEM is from 30.0% to 80.0%, and where a storage elastic modulus of the magnetic toner at 40° C. is taken as E?(40) [Pa] and a storage elastic modulus of the magnetic toner at 85° C. is taken as E?(85) [Pa], the following formulas (1) and (2) are satisfied: E?(85)?5.5×109??(1) [E?(40)?E?(85)]×100/E?(40)?30??(2).

Abstract: A toner comprising an external additive and a toner particle including a binder resin, a colorant and inorganic fine particles A, wherein the external additive contains an external additive B, a number average particle diameter of primary particles of the external additive B is 30 to 200 nm, an adhesion index of the external additive B to the toner particle is 0.00 to 3.00, a number average particle diameter of primary particles of the inorganic fine particles A is greater than that of the external additive B, and in SEM observations of the toner under specific condition, the number of particles (Na) of the external additive B in a 2 ?m square region of the toner surface and the number of particles (Nb) of the external additive B observed in a state of overlapping with the inorganic fine particles A in the region satisfy Nb/Na of 0.20 or more.

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 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 an external additive and a toner particle including a binder resin, a colorant and inorganic fine particles A, wherein the external additive contains an external additive B, a number average particle diameter of primary particles of the external additive B is 30 to 200 nm, an adhesion index of the external additive B to the toner particle is 0.00 to 3.00, a number average particle diameter of primary particles of the inorganic fine particles A is greater than that of the external additive B, and in SEM observations of the toner under specific condition, the number of particles (Na) of the external additive B in a 2 ?m square region of the toner surface and the number of particles (Nb) of the external additive B observed in a state of overlapping with the inorganic fine particles A in the region satisfy Nb/Na of 0.20 or more.

Abstract: A toner including: a toner particle that includes a binder resin and a crystalline material, wherein the binder resin includes a vinyl resin having an ether structure, and where intensities of secondary ion mass/secondary ion charge number (m/z) of 59, 44, and 135 are denoted by A (ppm), B (ppm), and C (ppm), respectively, in a measurement of the toner by time-of-flight secondary ion mass spectrometry, the intensities at 100 nm from the surface of the toner satisfy the relationships of the following formulas (1) and (2): C/(A+B)?1.00??(1) (A+B)?2000??(2).

Abstract: A toner including: a toner particle that includes a binder resin; and an external additive, wherein a toner hardness A N/m and a toner hardness B N/m satisfy B?600 and B/A?1.30, in the formulas, the toner hardness A is an average value of a slope in a displacement region of from 0.00 ?m to 0.20 ?m when measuring the toner under a condition of a load application speed of 0.83 ?N/sec, and the toner hardness B is an average value of a slope in a displacement region of from 0.00 ?m to 0.20 ?m when measuring the toner under a condition of a load application speed of 2.50 ?N/sec.

Abstract: A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein a storage elastic modulus E?(40) [Pa] at 40° C. and a storage elastic modulus E?(85) [Pa] at 85° C., which are obtained in a powder dynamic viscoelasticity measurement of the magnetic toner, satisfy the following formulas (1) to (3). E?(40)?6.0×109 ??(1) E?(85)?5.

Abstract: A magnetic toner comprising a magnetic toner particle including a binder resin, a magnetic body and a crystalline polyester, wherein the dielectric loss tangent at 100 kHz is 1.0×10?2 or more, a variation coefficient CV3 of an occupied area ratio of the magnetic body when a cross section of the magnetic toner particle is divided by a square grid having a side of 0.8 ?m in cross-sectional observation of the magnetic toner particle using a transmission electron microscope TEM is from 30.0% to 80.0%, and where a storage elastic modulus of the magnetic toner at 40° C. is taken as E?(40) [Pa] and a storage elastic modulus of the magnetic toner at 85° C. is taken as E?(85) [Pa], the following formulas (1) and (2) are satisfied: E?(85)?5.

Abstract: A magnetic toner is provided, which has a magnetic toner particle containing a binder resin, a wax, and a magnetic body, wherein, when Dn is a number-average particle diameter of the toner, CV1 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?0.500 to +0.500, and CV2 is coefficient of variation of a brightness variance value of the toner in a particle diameter range of Dn ?1.500 to ?0.500, a relationship CV2/CV1?1.00 is satisfied; an average brightness of the toner in the range of Dn ?0.500 to +0.500 is 30.0 to 60.0; and when, in a cross section of the toner observed using a transmission electron microscope, which is divided with a square grid having a side of 0.8 ?m, coefficient of variation CV3 of an occupied area percentage for the magnetic body is 40.0 to 80.0%.

Abstract: A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E? with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than ?1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than ?1.00×108; (II) the storage elastic modulus E? (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E? (120) of the toner at 120° C., E? (50) and E? (120) satisfy 1.50?[E? (50)]/[E? (120)]?3.00.

Abstract: Provided is a toner having a toner particle including a binder resin and a colorant, wherein the toner has a softening point of at least 100° C. and not more than 150° C., and when Tgt represents a glass transition temperature (° C.) of the toner during a second temperature rise as measured with a DSC, Tgf represents a glass transition temperature (° C.) of a tetrahydrofuran-insoluble matter of the binder resin during a second temperature rise as measured with a DSC, and Tgk represents a glass transition temperature (° C.) of a tetrahydrofuran-soluble matter of the binder resin during a second temperature rise as measured with a DSC, the toner satisfies Tgt>Tgf (1), Tgt>Tgk (2), and 35° C.?Tgf?70° C. (3).

Abstract: A toner having a toner particle containing a binder resin, an amorphous polyester, and a colorant, wherein a softening point of the toner is at least 110° C. and not more than 140° C.; an integrated value f1 for stress of the toner is not more than 10 g·m/sec, as measured using a tack tester, with a temperature for a probe end being 150° C. and a press holding time being 0.01 seconds; and an integrated value f2 for stress of the toner is at least 30 g·m/sec, as measured using a tack tester, with a temperature for a probe end being 150° C. and a press holding time being 0.1 seconds.

Abstract: Provided is a toner, including: a toner particle; and an organic-inorganic composite fine particle on a surface of the toner particle, in which the organic-inorganic composite fine particle includes: a resin fine particle; and an inorganic fine particle embedded in the resin fine particle, and part of which is exposed to a surface of the composite fine particle, and in which the composite fine particle satisfies the following relationships: (i) in viscoelasticity measurement of the composite fine particle, when the loss elastic modulus thereof at a temperature T (° C.) is represented by G?T [dN/m2], a change ratio d(Log(G?T))/dT of a common logarithm of the loss elastic modulus has a minimum in a temperature range of from 60° C. to 150° C., and the minimum is less than ?0.10; and (ii) the loss elastic modulus (G?180) thereof at a temperature of 180° C. is 1.0×104 dN/m2 or more and 1.0×107 dN/m2 or less.

Abstract: A toner includes toner particles and an external additive; the external additive includes an external additive A containing fine particles of a crystalline resin or fine particles of a wax; the crystalline resin and the wax each have an urethane bond or an urea bond; and the melting point of the crystalline resin and the melting point of the wax are each from 50° C. to 130° C.

Abstract: A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E? with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than ?1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than ?1.00×108; (II) the storage elastic modulus E? (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E? (120) of the toner at 120° C., E? (50) and E? (120) satisfy 1.50?[E? (50)]/[E? (120)]?3.00.