Abstract: A method for producing a recycled carrier includes: performing classification, the classification including separating a carrier having a coating layer from a collected developer by a centrifugal air classifier, the collected developer containing the carrier and being obtained by collecting an electrostatic charge image developer remaining after image formation; and performing recoating, the recoating including dissolving or thermally melting a coating resin of the separated and classified carrier and then coating the resulting carrier again to produce a recycled carrier.

Abstract: An electrostatic charge image developing carrier, containing: a magnetic particle; and a resin coating layer that coats the magnetic particle and contains inorganic particles, and the electrostatic charge image developing carrier has a surface roughness satisfying a ratio B/A of a surface area B to a plan view area A of 1.020 or more and 1.100 or less, the plan view area A and the surface area B being obtained by three-dimensional analysis of the surface, and the magnetic particle has a surface roughness satisfying 0.5 ?m?Sm?2.5 ?m and 0.3 ?m?Ra?1.2 ?m, and Sm represents an average ruggedness interval and Ra represents an arithmetic average surface roughness.

Abstract: A toner includes polyolefin and has an exothermic peak in a range from 40° C. to 70° C. in a cooling process of the polyolefin by the DSC after a first heating process of the polyolefin by DSC. The polyolefin does not have an exothermic peak in the cooling process of the polyolefin by the DSC after the first heating process of the polyolefin by the DSC, and has an exothermic peak in a range from 0° C. to 30° C. in a second heating process of the polyolefin by the DSC.

Abstract: A toner includes toner particles. The toner particles each include a toner mother particle and an external additive attached to the surface of the toner mother particle. The external additive includes specific external additive particles. The specific external additive particles have a number average primary particle diameter of at least 30 nm and no greater than 305 nm. The specific external additive particles include antimony-doped tin oxide particles or indium tin oxide particles. A ratio (MSb/(MSn+MSb)) of a mass (MSb) of an antimony atom to a total of the mass (MSb) of the antimony atom and a mass (MSn) of a tin atom in the antimony-doped tin oxide particles is at least 0.04 and no greater than 0.46.

Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the volume resistivity R1 of the matrix is 1.0×105 times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.

Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, a conductive layer of the conductive member comprises a matrix domain structure, at least a part of the domains Dt is exposed at the conductive member outer surface, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the domains Dt has a volume resistivity of smaller than R1, the developing device comprises the toner, domains Dc formed of the crystalline material exist in a cross section of the toner, distances between adjacent wall surfaces of the domains Dc is from 30 to 1,100 nm, and a weight-average particle diameter D4 of the toner and distances Dms between adjacent wall surfaces between the domains Dt satisfies D4?Dms.

Abstract: Provided in one example herein is a liquid electrophotographic varnish composition. The composition includes resin particles each including a polymeric resin mixture, which includes a first polymeric resin including an ethylene-based polymer; and a second polymeric resin including a polyamide. The composition also includes a carrier fluid.

Abstract: Toner comprising a toner particle, the toner particle includes a toner core particle and an organosilicon polymer covering the toner core particle surface, the organosilicon polymer has a structure represented by R4—SiO3/2 (R4 each independently represents an alkyl group having 1 to 6 carbon atoms or a phenyl group), the toner core particle includes a resin A having a substituted or unsubstituted silyl group in a molecule thereof, a substituent of the substituted silyl group is at least one selected from the group consisting of an alkyl group having 1 or more carbon atoms, an alkoxy group having 1 or more carbon atoms, a hydroxy group, a halogen atom, and an aryl group having 6 or more carbon atoms, a content of silicon atoms in the resin A is 0.02 to 10.00% by mass, and a content of silicon atoms in the organosilicon polymer is 30 to 50% by mass.

Abstract: A toner includes toner particles. The toner particles each include a toner mother particle containing a binder resin and an external additive. The external additive includes resin particles. The toner mother particles have a chargeability opposite to a chargeability of the resin particles. Each of the resin particles has an embedded portion embedded in a surface portion of the toner mother particle and a protruding portion protruding outward from the toner mother particle in a radial direction of the toner mother particle. In a cross section of the resin particle, a relationship 0.60?LA/(LA+LB)?0.80 is satisfied where LA represents a maximum length of the embedded portion in the radial direction of the toner mother particle and LB represents a maximum length of the protruding portion in the radial direction of the toner mother particle.

Abstract: A toner comprising a toner particle including a binder resin and a colorant and an external additive, wherein the external additive contains an external additive A having a Feret diameter of 60 to 200 nm, the external additive A is inorganic fine particles or organic-inorganic composite fine particles, adhesion index of the external additive A to the toner is 0.00 to 3.00, and penetration depth b and protrusion height c satisfy Relational expressions (1) and (2) below, where b (nm) denotes penetration depth of the external additive A, at a portion of the external additive A penetrating into the toner particle interior from the surface thereof, and c (nm) denotes a protrusion height of the external additive A at that portion, in an observation of an image resulting from image processing of a cross section of the toner using TEM; 60?b+c?200??(1), 0.15?b/(b+c)?0.30??(2).

Abstract: The invention relates to a security pigment of core-shell particles, comprising a core based on a thermoplastic material, a shell based on a condensation polymer, and an organic or metalorganic feature substance present in dissolved or finely distributed form in the core, wherein the mass fraction of the shell amounts to more than 25%, preferably 50%, particularly more than 100%, in relation to the mass of the core. The invention further relates to a method for producing the core-shell particles and to value documents having the core-shell particles.

Abstract: The invention relates to a security pigment of core-shell particles with an organic or metalorganic feature substance, in particular luminescent feature substance, present in dissolved or finely distributed form in the core. The invention further relates to a method for producing the core-shell particles and value documents having the core-shell particles.

Abstract: An image forming apparatus includes an image carrier; a charging section that charges a surface of the image carrier; an electrostatic charge image forming section that forms an electrostatic charge image on the charged surface of the image carrier; a developing section that has a container containing an electrostatic charge image developer and develops the electrostatic charge image formed on the surface of the image carrier into a toner image using the electrostatic charge image developer, the electrostatic charge image developer including toner for electrostatic charge image development, the toner containing toner particles and an external additive; a transfer section that transfers the toner image formed on the surface of the image carrier to a surface of a recording medium; a cleaning section that has a cleaning blade with which the cleaning section cleans the surface of the image carrier; and a lubricant supplying section that has a lubricant supplying member that supplies a lubricant to the contact por

Abstract: A process for preparing a (meth)acrylate comprising preparing an aqueous phase by combining water, one or more stabilizing agents, and one or more surfactants; preparing an oil phase by combining one or more free radical initiators, one or more monomers capable of undergoing radical polymerization, one or more crosslinking and/or graft-linking monomers, and stearyl methacrylate and/or lauryl methacrylate, wherein the free radical initiator is capable of partitioning preferentially into the oil phase; combining the aqueous and oil phases and mixing to form a suspension having oil droplets ranging in size from 1 to 10 microns; raising the temperature of the suspension to effect an initial polymerization forming a core polymer is provided.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: Provided is a toner, including a toner particle having: a toner base particle containing a binder resin and a colorant; and protrusion derived from a resin fine particle in a surface of the toner base particle, wherein the protrusion is covered with a condensation product of an organosilicon compound represented by the formula (1), and wherein the resin fine particle is in direct contact with the toner base particle.

Abstract: A toner includes toner particles. The toner particles each include a toner core and a shell layer covering a surface of the toner core. The toner core contains composite particles. The composite particles are particles of a composite of a releasing agent, an electrically conductive polymer, and a dopant. A ratio of an amount of the composite particles to a mass of the toner cores is at least 0.5% by mass and no greater than 15.0% by mass.

Abstract: A toner includes toner particles. The toner particles each include a toner core containing a binder resin, a first shell layer covering a surface of the toner core, and a second shell layer partially covering a surface of the first shell layer. The first shell layers include first domains composed of a first thermoplastic resin and second domains composed of a second thermoplastic resin. The first thermoplastic resin has a glass transition point of at least 35° C. and no greater than 66° C. The second thermoplastic resin has a glass transition point of at least 71° C. and no greater than 105° C. The second shell layers contain a third thermoplastic resin that is more hydrophobic than the first thermoplastic resin and the second thermoplastic resin. The third thermoplastic resin has a higher glass transition point than the first thermoplastic resin.

Abstract: An object of the present invention is achieved by an image forming method containing the steps of: forming a toner image by developing an electrostatic latent image with a toner; transferring the toner image on a recording medium; and fixing the toner image on the recording medium, wherein the fixing step of the toner image on the recording medium further contains the steps of: irradiating light having a wavelength range of 280 to 480 nm to the toner image; and applying pressure to the toner image.

Abstract: Provided is a toner that has a plurality of toner particles. Each toner particle can include a binder resin core and a shell disposed about the binder resin core. The binder resin core can include at least one binder resin. The shell can include a plurality of metal nanoparticles. The binder resin core can be prepared by forming an aggregate of the binder resin in which metallic nanoparticles are not present.

Abstract: A toner includes toner particles. The toner particles each include a composite core and a shell layer covering a surface of the composite core. The composite core is a composite of a toner core and organic particles located on a surface of the toner core. The toner core contains a releasing agent having a carboxyl group. The organic particles contain a resin having a carboxyl group and a mass average molecular weight of from 30,000 to 50,500. The shell layer includes a unit having a non-ring-opened oxazoline group. An amount of the non-ring-opened oxazoline group contained in 1 g of the toner as measured by gas chromatography-mass spectrometry is from 500 ?mol to 1,400 ?mol. An endothermic quantity due to melting of the releasing agent contained in 1 mg of the toner as measured by differential scanning calorimetry is from 80 mJ to 160 mJ.

Abstract: An image forming method uses a toner including toner particles including a binder resin and an ultraviolet light absorber. Content of the ultraviolet light absorber is within a range of 0.1 to 50 mass % with respect to total mass of the toner particles. The method includes: transferring a toner image formed with the toner on a recording medium; and irradiating the toner image transferred on the recording medium with monochromatic light having a maximum emission wavelength within a wavelength range of 280 to 550 nm to melt and fix the toner image.

Abstract: A toner includes a plurality of first particles and a plurality of second particles. The first particles and the second particles each include a core and a shell layer covering a surface of the core. The cores of the first particles contain a binder resin and a colorant. The cores of the second particles contain a releasing agent. A standard deviation of a volume-based particle size distribution of the toner is no greater than 1.28. An area ratio of regions of the cores of the second particles that are occupied by the releasing agent in a cross-sectional image of the second particles is at least 50%. A number ratio of the second particles is at least 5% and no greater than 25% relative to a total number of the first particles and the second particles.

Abstract: A process for preparing isosorbide di(meth)acrylate by transesterifying alkyl (meth)acrylate with isosorbide, comprising the steps of: (i) reacting alkyl (meth)acrylate with isosorbide in the presence of a catalyst comprising titanium(IV) or zirconium(IV) and a stabilizer in the presence of an azeotroping agent which forms an azeotrope with the alcohol bound in the alkyl (meth)acrylate, (ii) continuously distilling off the azeotrope of azeotroping agent and alcohol, wherein steps (i) and (ii) are conducted simultaneously until the isosorbide has been essentially fully converted, (iii) adding water to the product mixture which comprises isosorbide (meth)acrylate and is obtained in steps (i) and (ii) and removing the hydrolyzate of the catalyst comprising titanium(IV) or zirconium(IV), (iv) distilling unconverted alkyl (meth)acrylate and azeotroping agent out of the product mixture, (v) distilling off water from the product mixture, wherein step (iv) can also be conducted before step (iii) and steps (iv) and

Abstract: Provided are constituent particles containing a water-soluble material with high flowability in the form of powder, the constituent particles being capable of forming a support member that can be removed with a water-containing solvent in a process for producing a three-dimensional object. The constituent particles used for the production of a three-dimensional object each include a core and a shell that covers at least part of a surface of the core, the core containing a water-soluble material most abundantly, and a material contained in the shell most abundantly having a lower water solubility than the water-soluble material contained in the core.

Abstract: An electrostatic latent image developing toner includes toner particles each including a toner mother particle and an external additive. The toner mother particle includes a composite core and a shell layer. The composite core is a composite of a toner core, organic particles, and polyhedral magnetic particles. The organic particles each contain a releasing agent and adhere to a surface of the toner core. The magnetic particles include magnetic particles adhering to the surface of the toner core and magnetic particles adhering to surfaces of the organic particles. An amount of the magnetic particles is 0.5 parts by mass to 2.0 parts by mass relative to 100 parts by mass of the toner cores. In a cross-sectional image of each toner particle, an area of protruding portions of the magnetic particles, which protrude from the shell layer, accounts for 10% to 75% of an overall area of the magnetic particles.

Abstract: A toner comprising a binder resin and a colorant, wherein the toner has a Martens hardness, as measured at a maximum load condition of 2.0×10?4 N, of from 200 MPa to 1,100 MPa.

Abstract: Provided is a toner containing a toner particle including a binder resin, a wax, and a colorant. The softening point of the toner is at least 80° C. and not more than 140° C. The average circularity of the toner is at least 0.940. The integrated value of stress in the toner at 150° C. which is measured by using a tackiness tester is at least 78 g·m/sec.

Abstract: Provided is a toner including toner particles each containing an amorphous polyester resin and a wax, in which: the surface of each of the toner particles has a coating layer; and the coating layer contains one or more kinds of olefin-based copolymers each having a specific ester moiety.

Abstract: A developing device, including: a developer containing toner and carrier; and developer bearer configured to have surface thereof bear the developer and endlessly move, and to develop latent image over surface of latent image bearer by supplying toner in developer to latent image in developing region facing the latent image bearer, wherein carrier contains fine particles, value X in volume resistivity R (=10X) (?·cm) of carrier is 11.5-16.0, developer bearer includes: magnetic field generating unit including a plurality of magnetic poles; and developing sleeve having a cylindrical shape enclosing magnetic field generating unit, and configured to bear developer over outer circumferential surface of cylindrical shape by magnetic force of the magnetic field generating unit and perform surface moving by rotating relative to developing device body, and developing device includes developing sleeve voltage applying unit configured to apply AC component-containing voltage to developing sleeve.

Abstract: An electrostatic latent image developing toner includes a plurality of toner particles each including a toner mother particle and inorganic particles attached to a surface of the toner mother particle. The toner mother particle includes a toner core (11) and a shell layer (12) covering a surface of the toner core (11). The shell layer (12) includes film-shaped first domains (12a) and particle-shaped second domains (12b). The first domains (12a) are substantially formed from a non-cross-linked resin. The second domains (12b) are substantially formed from a cross-linked resin. The cross-linked resin has a glass transition point higher by 40° C. or more than that of the non-cross-linked resin. The first domains (12a) have a surface adsorption force of at least 20.0 nN and no greater than 40.0 nN. The second domains (12b) have a surface adsorption force of at least 4.0 nN and less than 20.0 nN.

Abstract: Provided is a toner including a toner particle that contains a toner base particle containing a binder resin and a wax, and a coating layer containing a 1,2-polybutadiene resin at the surface of the toner base particle, wherein the coverage ratio of the toner base particle by the coating layer is at least 50%.

Abstract: A toner comprising a toner particle that contains a binder resin, wherein the surface of the toner particle is covered with a resin A; the modulus of elasticity Ea of the resin A and the modulus of elasticity Eb of the binder resin satisfy the following formula: 0.5?(Ea/Eb)×100?50.0; and the adhesion force AT of the toner particle is at least 500 nN when a probe having spherical SiO2 attached at the tip of a cantilever is pressed into the toner particle at 3 ?N.

Abstract: In accordance with an embodiment, a toner particle comprises two or more glass transition temperatures. Wherein, a first glass transition temperature is within a range from 5 degrees centigrade to 20 degrees centigrade and a second glass transition temperature is within a range from 50 degrees centigrade to 65 degrees centigrade.

Abstract: A toner composite material includes toner particles that include a sulfonated polyester and a wax and metal nanoparticles disposed on the surface of the toner particles. A method includes providing such toner composite materials, fusing the material to a substrate and covalently linking a ligand to the surface of the silver nanoparticles via a thiol, carboxylate, or amine functional group. Detection strips include a substrate and such toner composite materials fused on the substrate.

Abstract: An electrostatic latent image developing toner includes toner particles each including a core and a shell layer. The shell layer is a collection of resin particles having the same composition (primary particle diameter of at least 90% by number of the resin particles: 20 nm-30 nm). The shell layer includes a first shell layer, which is a film including the resin particles in a non-aggregated state, and a second shell layer, which is a plurality of particle aggregates (secondary particle diameter of at least 90% by number of the particle aggregates: 100 nm-150 nm). The particle aggregates each include the resin particles in an aggregated state. The surface of the core is entirely covered with the shell layer. The second shell layer is present in a surface of the toner particle in a proportion of at least 5% by area and no greater than 15% by area.

Abstract: An electrostatic latent image developing toner includes toner particles each including a toner core (11) and a shell layer (12) disposed over a surface of the toner core (11). The toner core (11) contains a polyester resin. The shell layer (12) includes: first resin particles (12a) having a number average primary particle diameter of at least 30 nm and less than 70 nm and a glass transition point of less than 80° C.; and second resin particles (12b) having a number average primary particle diameter of 70-200 nm and a glass transition point of at least 80° C. A percentage of an area of the toner core (11) covered with the first resin particles (12a) relative to a surface area of the toner core (11) is 40-80%. A ratio of total mass of the second resin particles (12b) to total mass of the first resin particles (12a) is 0.5-2.0.

Abstract: Provided is a toner including toner particles, each of which contains a binder resin, a colorant, a releasing agent and a crystalline polyester, wherein in an observation of a cross-section each of the toner particles by transmission electron microscopy, specific toner particles each of which has domains of the crystalline polyester and domains of the releasing agent, are present at a ratio of at least 70% by number of the toner particles in the toner, an arithmetic mean of maximum diameters of the domains of the releasing agent is within prescribed range, and the specific toner particles satisfy prescribed conditions.

Abstract: An electrostatic latent image developing toner includes toner particles each including a core and a shell layer disposed over a surface of the core. The shell layer contains first resin particles having a number average particle diameter of 60 nm to 100 nm and second resin particles having a number average particle diameter of 10 nm to 50 nm. A particle diameter difference obtained by subtracting the number average particle diameter of the second resin particles from the number average particle diameter of the first resin particles is +20 nm to +50 nm. The first resin particles contain a charge control agent. The first resin particles have a higher softening point than the second resin particles. A ratio of a mass of the first resin particles to a sum of the mass of the first resin particles and a mass of the second resin particles is 0.7 to 0.9.

Abstract: A positively chargeable toner includes a plurality of toner particles each including a core and a shell layer disposed over a surface of the core. The core contains a polyester resin. The shell layer covers at least 40% and no greater than 80% of an area of the surface of the core, ?(4) is greater than 0 V. ?(6) is less than 0 V. A relationship represented by |?(3)??(4)|>|?(6)??(7)| is satisfied. ?(3), ?(4), ?(6), and ?(7) represent zeta potentials of the positively chargeable toner with the toner particles having no external additive. ?(3), ?(4), ?(6), and ?(7) are respectively measured in an aqueous medium at pH 3, pH 4, pH 6, and pH 7.

Abstract: A complex particle including a core particle and a shell particle, wherein the shell particle is disposed on the core particle, wherein the core particle includes an organic material or an inorganic material as a primary component and the shell particle includes the other of the organic material and the inorganic material as a primary component, wherein an average particle diameter of the core particle is greater than or equal to about 80 nanometers and less than or equal to about 300 nanometers, a coefficient of variation of an average particle diameter of the core particle is greater than or equal to about 2% and less than or equal to about 10%, an average particle diameter of the shell particle is greater than or equal to about 5 nanometers and less than or equal to about 30 nm, a ratio of the average particle diameter of the shell particle relative to the average particle diameter of the core particle is greater than or equal to about 0.016 and less than or equal to about 0.

Abstract: A process for producing a toner of the present invention includes: a first step of heating a dispersion containing an aqueous medium and a binder resin containing a crystalline resin to a temperature higher than or equal to a melting point of the crystalline resin; and a second step of maintaining the dispersion at temperature T (° C.) for 30 minutes or longer in a state where a pH of the dispersion is maintained at 5.5 or higher and 9.0 or lower, in which the temperature T satisfies the following expression, Rc?25?T?Rc?5, where the Rc represents a recrystallization temperature (° C.) of the crystalline resin.

Abstract: A plurality of toner particles each include a toner core, a shell layer covering a surface of the toner core, and a plurality of magnetic particles penetrating the shell layer. Each of the magnetic particles has an embedded portion and a protrusion portion. The embedded portions are embedded in the surface of the toner core. The protrusion portions are located further outward than the embedded portions in a radial direction of the toner particle and protrude outward from a surface of the shell layer in the radial direction of the toner particle. An average Heywood diameter X of the magnetic particles, a shell layer thickness Y, and an average value Z of protrusion heights of the respective magnetic particles satisfy relation (1) and relation (2) shown below.

Abstract: A method of producing a toner for developing electrostatic images includes Steps I to III is provided. The toner includes a toner matrix particle having a core-shell structure. The toner matrix particle includes a core particle including an amorphous resin A and a crystalline material, and a shell including an amorphous resin B. The shell includes a phase of the amorphous resin B that is not fused with the core particle at the interface. The amorphous resin A differs from the amorphous resin B.

Abstract: Provided is an electrostatic latent image developing toner that, while ensuring low temperature fixability, can ensure image quality stability even during high-speed continuous printing. The toner is an electrostatic latent image developing core-shell type toner containing at least a binder resin. The binder resin includes a crystalline polyester resin, an amorphous polyester resin, and a hybrid amorphous vinyl resin in which a vinyl polymerization segment is chemically bonded to a polymerization segment other than the vinyl polymerization segment, in which a core portion of the toner contains the crystalline polyester resin and the amorphous polyester resin, whereas a shell portion of the toner contains the hybrid amorphous vinyl resin, and the hybrid amorphous vinyl resin has a vinyl polymerization segment content of from 51 to 99% by mass.

Abstract: The object of the present invention is to provide a toner for development of electrostatic images (hereinafter referred to as toner) which, while preventing dust during fixation, secures improved hot offset resistance and is excellent in providing good image quality. The invention relates to the toner that comprises a binder resin, a colorant and a wax, wherein the wax has, while in a state of being contained in the toner, a melting point of from 55° C. to 90° C., and the value Dt of the toner satisfies a specific formula.

Abstract: Disclosed herein include toner compositions with toner particles having a core-shell type structure, where the core comprises a first resin comprising a styrene-acrylate copolymer and an amorphous polyester resin, and the shell comprises a second resin comprising beta-carboxyethyl acrylate (b-CEA) in an amount of from about 0.05 pph to about 2.5 pph by weight of the second resin.

Abstract: Disclosed is a toner including toner particles each including a core portion that contains a binder resin, and a surface layer containing an organosilicon polymer, in which each of the toner particles contains a polyvalent metal element having a resistivity of 2.5×10?8 ?·m or more and 10.0×10?8 ?·m or less at 20° C., and when the toner particles are subjected to X-ray fluorescence analysis, a net intensity originating from the polyvalent metal element is 0.10 kcps or more and 30.00 kcps or less.

Abstract: An electrostatic latent image developing toner includes a plurality of toner particles each including a core containing a binder resin and a shell layer covering a surface of the core. The shell layer contains a copolymer of at least two vinyl compounds including a compound represented by the following formula (1). The toner contains a ring unopened oxazoline group in an amount of at least 0.10 ?mol/g and no greater than 100 ?mol/g.

Abstract: An electrostatic latent image developing toner includes a plurality of toner particles each including a core and a shell layer. The shell layer is disposed over a surface of the core. The shell layer is substantially formed by a resin. The shell layer has a surface including a plurality of spot regions and a sheet region that is more hydrophobic than the spot regions. The spot regions each are more chargeable than the sheet region.