Patent classifications
G03G9/1139
POSITIVELY CHARGED TONER FOR ELECTROSTATIC-IMAGE DEVELOPMENT
A positively charged toner for development of an electrostatic image, containing matrix particles containing at least a binder resin and a release agent, coated with inorganic fine particles, the binder resin containing a crystalline resin, the release agent containing ester wax (W) containing a dipentaerythritol unit as a constitutional component, the inorganic fine particles containing positively charged silica (S1) and negatively charged silica (S2), and the positively charged silica (S1) having an average particle diameter that is smaller than an average particle diameter of the negatively charged silica (S2), and the negatively charged silica (S2) having an average particle diameter of 10 nm or more and 90 nm or less.
Carrier for forming electrophotographic image, two-component developer, developer for replenishment, image forming apparatus, process cartridge, and image forming method
A carrier for forming an electrophotographic image is provided. The carrier comprises carrier particles each comprising a core particle and a coating layer. The coating layer comprises a coating resin and inorganic particles comprising chargeable particles A and conductive particles B. The amount of the inorganic particles is from 195 to 350 parts by mass with respect to 100 parts by mass of the coating resin. The carrier particles consist of small carrier particles (D1≤25 μm), medium carrier particles (25 μm<D2≤38 μm), and large carrier particles (38 μm<D3). A constituent element variation, that is a ratio of an amount of a constituent element of the inorganic particles contained in the coating layer of the small carrier particles to an amount of the same constituent element of the inorganic particles contained in the coating layer of the medium carrier, is from −10.0% to 10.0%.
CARRIER FOR FORMING ELECTROPHOTOGRAPHIC IMAGE, DEVELOPER FOR FORMING ELECTROPHOTOGRAPHIC IMAGE, ELECTROPHOTOGRAPHIC IMAGE FORMING METHOD, ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS, AND PROCESS CARTRIDGE
A carrier for forming an electrophotographic image is provided. The carrier comprises a core particle and a resin layer coating the core particle. The resin layer contains a chargeable particle A, a conductive particle B, a dispersing agent, and a defoaming agent.
PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS
A process cartridge is provided, which is configured to recover, with a developing member, developer remaining on an image bearing member after transfer of a developer image to a transfer receiving member, wherein a charging member has a shaft that is conductive and an elastic layer supported on the shaft and being in contact with the image bearing member; the elastic layer has a matrix containing a first rubber, and a plurality of domains containing a second rubber and an electron-conductive agent and interspersed within the matrix. The electric resistance of the domains is lower than the electric resistance of the matrix. The matrix is exposed on an outer surface of the elastic layer and forms multiple depressed portions, and the domains include a domains exposed at a bottom section of the depressed portion.
TONER
A toner comprises a toner particle and silica fine particles, wherein, fragment ions of a D unit structure are observed in time-of-flight secondary ion mass spectrometry measurement of the silica fine particles, in a titration operation of the silica fine particles using NaOH, the titer is within a specific range, an area of a peak from 25 to 15 ppm in .sup.29Si-NMR measurement of the silica fine particles is denoted by D, the sum of the areas of peaks from 140 to 100 ppm is denoted by S, and an area of a peak from more than 19 ppm to 17 ppm or less is denoted by D1, the specific surface area of the silica fine particles, D, D1, and S satisfy specific relationships, and a specific amount of a specific polyvalent metal element is present on the surface of the toner particle.
Carrier for developing electrostatic latent image, two-component developer, developer for replenishment, image forming device, process cartridge, and image forming method
A carrier for developing an electrostatic latent image includes a core material particle and a resin layer covering a surface of the core material particle. The resin layer includes a resin and at least one kind of a fine particle. At least one kind of the fine particles includes a chargeable fine particle. The chargeable fine particle has a long diameter of 400 to 900 nm. The chargeable fine particle has a shape factor SF-1 of 160 to 250.
ELECTROSTATIC CHARGE IMAGE DEVELOPMENT TONER, ELECTROSTATIC CHARGE IMAGE DEVELOPER, TONER CARTRIDGE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
An electrostatic charge image development toner contains toner particles and layered-structure compound particles. The layered-structure compound particles have a crystallite diameter of 150 or more and 250 or less as calculated from a maximum peak width in a Cu K X-ray diffraction chart and have a number-average particle diameter Dn of 0.3 m or more and 2.0 m or less. The ratio Dn/Dv of a number-average particle diameter Dn of the layered-structure compound particles to a volume-average particle diameter Dv of the toner particles is 0.03 or more and 0.7 or less.
ELECTROSTATIC-IMAGE DEVELOPING TONER, ELECTROSTATIC-IMAGE DEVELOPER, TONER CARTRIDGE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
An electrostatic-image developing toner includes toner particles, layered compound particles, and a free oil. The mass ratio Ma/Mb of the content Ma of the layered compound particles to the content Mb of the free oil is 0.05 or more and 100 or less.
ELECTROSTATIC CHARGE IMAGE DEVELOPMENT TONER, ELECTROSTATIC CHARGE IMAGE DEVELOPER, TONER CARTRIDGE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
An electrostatic charge image development toner that is negatively chargeable contains toner particles and layered-structure compound particles. The layered-structure compound particles have a volume-average particle diameter Da of 0.4 m or more and less than 3.0 m. The ratio Da/Db of the volume-average particle diameter Da of the layered-structure compound particles to the volume-average particle diameter Db of the toner particles is 0.044 or more and 0.625 or less.
ELECTROSTATIC-IMAGE DEVELOPING TONER, ELECTROSTATIC-IMAGE DEVELOPER, TONER CARTRIDGE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
An electrostatic-image developing toner includes toner particles, layered compound particles, and inorganic particles. The inorganic particles have an average circularity of 0.910 or more and 0.995 or less. A ratio Da/Db of a number-average particle size Da of the layered compound particles to a number-average particle size Db of the inorganic particles is 1.2 or more and 43 or less.