Patent classifications
G03G9/113
CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE AND METHOD FOR PRODUCING THE SAME, ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
A carrier for developing an electrostatic charge image includes magnetic particles and a resin coating layer covering the magnetic particles, the resin coating layer containing inorganic particles. The ratio M1/M2 is 0.8 or more and 1.2 or less, where M1 is the concentration of the inorganic particles in the resin coating layer within a distance of 300 nm from the carrier surface, and M2 is that within a distance of 300 nm from the surface of the resin coating layer closer to the magnetic particle, and the percentage surface exposure of the magnetic particles is 0% by area or more and 5% by area or less. A cavity lies at least in part between the resin coating layer and a surface of the magnetic particles, and the average width, or the average length parallel to the thickness of the resin coating layer, of the cavity is 50 nm or more and 500 nm or less.
CARRIER FOR ELECTROSTATIC IMAGE DEVELOPMENT, ELECTROSTATIC IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
A carrier for electrostatic image development includes: a core material; and a resin coating layer that contains nitrogen-containing silica particles and nitrogen-containing resin fine particles and covers the core material. The content of the nitrogen-containing silica particles is from 10% by mass to 55% by mass inclusive based on the total mass of the resin coating layer. The nitrogen-containing resin fine particles have a volume average particle diameter of from 100 nm to 250 nm inclusive. The mass ratio P/S of the mass P of the nitrogen-containing resin fine particles to the mass S of the nitrogen-containing silica particles is from 0.15 to 0.55 inclusive.
ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
An electrostatic charge image developer contains toner particles, silica particles that are added to an exterior of the toner particles and contain a nitrogen element-containing compound, and a carrier that has a core material and a nitrogen element-containing coating resin layer, in which a content of the nitrogen element-containing compound with respect to the silica particles is 0.005% by mass or more and 0.5% by mass or less in terms of a nitrogen element, and in a case where A represents a pore volume of pores that the silica particles include and have a diameter of 1 nm or more and 50 nm or less, which is determined from a pore size distribution curve obtained by a nitrogen adsorption method before baking of the silica particles at 350° C., and B represents a pore volume of pores that the silica particles include and have a diameter of 1 nm or more and 50 nm or less, which is determined from a pore size distribution curve obtained by a nitrogen adsorption method after baking of the silica particles at 350° C., B/A is 1.2 or more and 5 or less and B is 0.2 cm.sup.3/g or more and 3 cm.sup.3/g or less.
Nanocomposites containing crystalline polyester and organosilica
The invention provides a process for preparing core-shell composite particles comprising a polyester, polymerized ethylenically unsaturated silane compounds, and optionally a hydrophobic surface treatment. The invention further provides a composite particle comprising a polyester and a radically polymerized ethylenically unsaturated silane compound.
METHOD FOR PRODUCING CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER, IMAGE FORMING METHOD, AND IMAGE FORMING APPARATUS
A method for producing a carrier for developing an electrostatic charge image, the method includes: adding a coating liquid containing a resin, conductive particles, and a solvent and magnetic particles to a mixer having a stirring blade, and mixing the coating liquid and the magnetic particles to obtain a mixture; and evaporating and drying the solvent from the mixture to produce a carrier having a resin coating layer on surfaces of the magnetic particles, wherein a viscosity μ of the coating liquid when being added to the mixer is more than 60 mPa.Math.s and 1,000 mPa.Math.s or less, and a value of a ratio μ/W of the viscosity μ(mPa.Math.s) to an amount W (parts by mass) of the resin coating layer with respect to 100 parts by mass of the magnetic particles in the carrier is 20 or more and 500 or less.
METHOD FOR PRODUCING CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE, ELECTROSTATIC CHARGE IMAGE DEVELOPER, IMAGE FORMING METHOD, AND IMAGE FORMING APPARATUS
A method for producing a carrier for developing an electrostatic charge image, the method includes: adding a coating liquid containing a resin, conductive particles, and a solvent and magnetic particles to a mixer having a stirring blade, and mixing the coating liquid and the magnetic particles to obtain a mixture; and evaporating and drying the solvent from the mixture to produce a carrier having a resin coating layer on surfaces of the magnetic particles, wherein a viscosity μ of the coating liquid when being added to the mixer is more than 60 mPa.Math.s and 1,000 mPa.Math.s or less, and a value of a ratio μ/W of the viscosity μ(mPa.Math.s) to an amount W (parts by mass) of the resin coating layer with respect to 100 parts by mass of the magnetic particles in the carrier is 20 or more and 500 or less.
CARRIER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE AND METHOD FOR PRODUCING THE SAME, ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD
A carrier for developing an electrostatic charge image includes magnetic particles and a resin coating layer covering the magnetic particles, the resin coating layer containing aggregates of inorganic particles. The arithmetic mean diameter of the aggregates of inorganic particles on the carrier surface is 30 nm or more and 150 nm or less, and the percentage surface exposure of the magnetic particles is 0% by area or more and 5% by area or less.
Carrier for developer and developer
A carrier for a developer includes carrier particles. The carrier particles have a sea island structure including a sea portion and an island portion on the surface. The island portion contains a nitrogen-containing silicone resin. The sea portion contains a nitrogen-free silicone resin. The area ratio of the island portion in the total area of the surface of the carrier particle is 20% or more and 40% or less.
Two-component developer, developing device, and image forming device
A two-component developer 100 includes a carrier 200 and a toner 300. The carrier 200 satisfies the relationships 100≤α≤220 and 300≤β≤480 when a voltage is applied in 1 V steps by a bridge resistance measurement method, where α (V) is a carrier voltage value obtained when a current value flowing through the carrier 200 reaches 1.0.sup.−7 (A), and β (V) is a carrier voltage value obtained when the current value reaches 1.0.sup.−5 (A).
Two-component developer, developing device, and image forming device
A two-component developer 100 includes a carrier 200 and a toner 300. The carrier 200 satisfies the relationships 100≤α≤220 and 300≤β≤480 when a voltage is applied in 1 V steps by a bridge resistance measurement method, where α (V) is a carrier voltage value obtained when a current value flowing through the carrier 200 reaches 1.0.sup.−7 (A), and β (V) is a carrier voltage value obtained when the current value reaches 1.0.sup.−5 (A).