Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, a conductive part, an element part, and first to fourth terminals. The conductive part is electrically insulated from the first and second magnetic poles. The first and second terminals are electrically connected to the conductive part. The element part is provided between the first and second magnetic poles and electrically connected to the first and second magnetic poles. The element part is conductive. The third terminal is electrically connected to the first magnetic pole. The fourth terminal is electrically connected to the second magnetic pole. A first magnetic pole temperature in a first state is higher than a second magnetic pole temperature of the second magnetic pole in the first state. A first current is supplied between the first and second terminals in the first state.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material, at least one of a polyester resin (PEz) or a polycarbonate resin (PCz) that has at least one of a structure (Z1) represented by Formula (Z1) or a structure (Z2) represented by Formula (Z2) at at least one terminal, and a resin (X) that has at least one of a unit (X1) represented by Formula (X1) or a unit (X2) represented by Formula (X2), a mass proportion of the resin (X) in a total amount of the polyester resin (PEz), the polycarbonate resin (PCz), and the resin (X) in the charge transport layer is 0.

Abstract: An evaluation method of an image stabilization effect of an imaging device includes calculating an evaluation value of the image stabilization effect on the basis of shutter speed values in case of which each of a reference shake amount theoretically calculated on the basis of a shake waveform applied to the imaging device and a measured shake amount calculated using an image captured in a state in which the imaging device is vibrated becomes a specified shake amount, and setting the specified shake amount. The setting includes calculating an image deterioration amount of the imaging device caused by something other than a shake from the outside, and selecting a determination level that defines the specified shake amount from a plurality of determination levels having different shake amounts on the basis of the image deterioration amount.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer including a charge generation layer and a charge transport layer or a single layer type photosensitive layer that is a photosensitive layer disposed on the conductive substrate, in which the charge transport layer or the single layer type photosensitive layer is an outermost layer and contains a charge transport material and a binder resin containing a polyester resin having an aromatic ring, the charge transport layer or the single layer type photosensitive layer has an average thickness of 28 ?m or greater and 50 ?m or less, and a weight reduction ratio of the charge transport layer or the single layer type photosensitive layer from 30° C. to 175° C. in thermogravimetric analysis is 0.1% by mass or less.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer including a charge generation layer and a charge transport layer or a single layer type photosensitive layer that is a photosensitive layer disposed on the conductive substrate, in which the charge transport layer or the single layer type photosensitive layer is an outermost layer and contains a charge transport material, a polyester resin having a dicarboxylic acid unit (A) represented by Formula (A), and a compound that has a molecular weight of 255 or greater, has a phenol skeleton in which a primary carbon atom or a secondary carbon atom is bonded to one ortho position and a tertiary carbon atom or a quaternary carbon atom is bonded to the other ortho position, and has no linear alkylene structure having 4 or more carbon atoms.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material, a polyester resin, and a polycarbonate resin, and the polyester resin includes the following polyester resin (1), polyester resin (1): a polyester resin having at least one selected from the group including a diol unit (B3) represented by Formula (B3), a diol unit (B5) represented by Formula (B5), a diol unit (B6) represented by Formula (B6), a diol unit (B7) represented by Formula (B7), a diol unit (B8) represented by Formula (B8), a diol unit (B9) represented by Formula (B9), a diol unit (B10) represented by Formula (B10), and a diol unit (B11) represented by Formula (B11), in Formula (B3), Rb113 and Rb213 each independently represent a hydrogen atom, a linear alkyl group having 1 or more and 3 or less

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer in this order, in which the charge transport layer contains at least one resin selected from a polyester resin or a polycarbonate resin, and in a case where a Martens hardness and an indentation hardness, which are acquired by an indentation test performed on the charge transport layer to a depth of 0.5 ?m, are respectively defined as HM (N/mm2) and nIT (N/mm2), Relational Equation (0) is satisfied, an elastic deformation modulus is 45% or greater and 70% or less, and a tensile elastic modulus of the charge transport layer is 2,300 MPa or greater and 5,000 MPa or less, nIT=a×HM?b(a=2±0.2,b=100±20).

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a polyester resin having a structure represented by Formula (1) at a terminal and a charge transport material, and in a case where a weight-average molecular weight Mw of the polyester resin is defined as A (×10,000), a value of a ratio M1/M2 of a mass M1 of the charge transport material to a mass M2 of an entire charge transport layer is defined as Cs, and an average thickness of the charge transport layer is defined as Ds (?m), expressions of 7?A?40, 0.28?Cs?0.55, 27?Ds?50, and 5.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, an undercoat layer disposed on the conductive substrate, and a lamination type photosensitive layer disposed on the undercoat layer and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material and a polyester resin, and in a case where an average thickness of the charge transport layer is defined as As (?m) and an average thickness of the undercoat layer is defined as Bs (?m), expressions 27?As?50, 10?Bs?40, and 0.70?As/Bs?4.80 are satisfied.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material, at least one of a polyester resin that has a constitutional unit having an aromatic ring or a polycarbonate resin that has a constitutional unit having an aromatic ring, and a compound (1) represented by Formula (1) and having a melting point of 40° C. or higher, in Formula (1), Ar represents an aromatic ring that may have a substituent, L represents a single bond, an oxygen atom, or a sulfur atom, R represents an alkyl group having 1 or more and 10 or less carbon atoms, an aryl group having 6 or more and 20 or less carbon atoms, or an aralkyl group having 7 or more and 20 or less carbon atoms, and n represents an integer of 1 or greater.

Abstract: An image forming unit includes a photoreceptor and a charging member that comes into contact with a surface of the photoreceptor and charges the photoreceptor, in which the photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, the charge transport layer contains at least one of a polyester resin that has a constitutional unit having an aromatic ring or a polycarbonate resin that has a constitutional unit having an aromatic ring, the charging member includes a support member and an elastic layer disposed on the support member, and the elastic layer has a storage elastic modulus G? of 5.0 MPa or less at a frequency of 100 Hz in dynamic viscoelasticity measurement under a temperature condition of 24° C.

Abstract: A gas control device includes a pump, a valve, a cuff, and a controller. The valve includes a first plate having a first vent hole and a first vent hole, a channel forming plate having an exhaust hole and an exhaust channel, a second plate having a second vent hole, and an edge separation plate. A manchette rubber tube in the cuff is joined to the periphery of the second vent hole in the second plate by an adhesive, and thus the valve is connected to the cuff. The exhaust hole is opened to the atmosphere. The pump includes a pump housing having a discharge hole and a discharge hole. The upper surface of the pump housing is joined to the bottom surface of the edge separation plate.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material and a polyester resin, and a mass proportion of a chemical substance (AA) represented by Formula (AA) in a total mass of the charge transport layer is 2,000 ppm or less. In Formula (AA), X represents an organic group, and mAA represents an integer.

Abstract: An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a polyester resin (1) having a dicarboxylic acid unit (A) represented by Formula (A) and a diol unit (B) represented by Formula (B), and a charge transport material, and in a case where a weight-average molecular weight Mw of the polyester resin (1) contained in the charge transport layer is defined as A (10,000), a value of a ratio M1/M2 of a mass M1 of the charge transport material contained in the charge transport layer to a mass M2 of the charge transport layer is defined as Cs, and an average thickness of the charge transport layer is defined as Ds (?m), expressions of 5?A?40, 0.28?Cs?0.55, 27?Ds?50, and 2.5?(A×Ds)/(Cs×100)?70.0 are satisfied.

Abstract: An electrophotographic photoconductor includes a conductive substrate, and a photoconductive layer, in which an outermost surface layer contains a binder resin, a charge transporting material, fluorine-containing resin particles, and an acidic compound, the number of carboxyl groups in the fluorine-containing resin particles is 0 or more and 30 or less per 106 carbon atoms of the fluorine-containing resin particles, and in a case where charging and exposure of the electrophotographic photoconductor are repeated 10,000 times under conditions of a charging potential of ?700 V and an exposure intensity of 5 mJ/m2, an absolute value |RP1?RP10000| of a difference between a residual potential RP1 after charging and exposure once and a residual potential RP10000 after charging and exposure 10,000 times is 25 V or less.

Abstract: A charging member includes a conductive substrate, an elastic layer disposed on the conductive substrate, and a surface layer disposed on the elastic layer. Regarding the surface of the surface layer, in the axial direction, the ratio of the mean spacing of profile irregularities Sm to the ten-point mean roughness Rz and the reduced peak height Spk respectively satisfy 15?Sm/Rz?35 and Spk?5 ?m.

Abstract: A charging device includes: a charging member that charges an electrophotographic photoconductor by a contact charging method and includes a conductive substrate, an elastic layer provided on the conductive substrate, and a surface layer that is provided on the elastic layer and contains irregularities-forming particles that have a number particle size distribution with two or more maximum values when observed, from a surface of the surface layer, and a voltage application unit that applies, to the charging member, an AC voltage superimposed on a DC voltage.

Abstract: A charging device includes a charging roller and a cleaning roller that includes a core and a foamed elastic layer disposed on an outer circumferential surface of the core and that rotates in contact with a surface of the charging roller. The number of ends of a cell skeleton that protrude from a surface of the foamed elastic layer is 25 ends/mm2 or more and 50 ends/mm2 or less. The cleaning roller is disposed in contact with the charging roller such that the compression ratio of the foamed elastic layer is 30% or less. The compression ratio is represented by Equation (1): compression ratio (%)=(r1/2+r2/2?d)/t1×100??Equation (1): where r1 is the outer diameter (mm) of the cleaning roller, r2 is the outer diameter (mm) of the charging roller, d is the interaxial distance (mm) between the charging roller and the cleaning roller, and t1 is the thickness (mm) of the foamed elastic layer of the cleaning roller.

Abstract: A charging member includes a conductive substrate, an elastic layer disposed on the conductive substrate, and a surface layer disposed on the elastic layer. Regarding the surface of the surface layer, in the axial direction, the ratio of the mean spacing of profile irregularities Sm to the ten-point mean roughness Rz and the reduced peak height Spk respectively satisfy 15?Sm/Rz?35 and Spk?5 ?m.

Abstract: A charging device includes: a charging member that charges an image holding member according to a contact charging method, and includes a conductive substrate and a surface layer provided on the conductive substrate; and a clean member that cleans the charging member while contacting the charging member, and includes a shaft and a foamed elastic layer provided on the shaft, wherein a ratio of a distance between irregularities in an axial direction of the surface layer in the charging member (Sm) to a width of a nodal section of a foam cell wall surface protruding from a surface of the foamed elastic layer in the clean member (W) satisfies 2.4?Sm/W?5.9.