Patent classifications
G03G9/09716
SILICONE OIL-TREATED SILICA PARTICLES AND TONER FOR ELECTROPHOTOGRAPHY
A silicone oil-treated silica particle according to the present invention includes a silica particle body and silicone oil. The silica particle body has a BET specific surface area of 70 m.sup.2/g to 120 m.sup.2/g. The silica particle body has been surface-treated with the silicone oil. The amount of free silicone oil liberated from the surface of the silica particle body in the silicone oil accounts for 2.0 mass % to 5.0 mass % with respect to the silica particle body. A surface-treated styrene acrylic resin particle, in which 2 parts by mass of the silicone oil-treated silica particle has been added to 100 parts by mass of a styrene acrylic resin particle having a particle size median of 5 μm to 8 μm, has a degree of agglomeration of 18 % or less.
ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrostatic charge image developer includes: toner particles; silica particles treated with a silicone oil, which are externally added to the toner particles; and a carrier, wherein a volume average particle diameter of the carrier is equal to or greater than 20 μm and smaller than 30 μm, and a quantity ratio of an elemental silicon derived from a silicone oil and an elemental silicon derived from silica which are present on the surface of the carrier (silicone oil-derived elemental silicon/silica-derived elemental silicon) is in a range of 0.05 to 0.2.
IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD USING A TONER CARRIER CONTAINING SILICON DERIVED FROM SILICA AND SILICONE OIL
An image forming apparatus includes a charging unit that includes a conductive member which contacts with a surface of an image holding member, and that applies only a DC voltage to the conductive member to charge the surface of the image holding member; and a cleaning unit that has a blade which contacts with the surface of an image holding member and cleans the surface with the blade after a toner image is transferred onto a recording medium, wherein a developer includes toner particles, silica particles treated with a silicone oil, and a carrier, a volume average particle diameter of the carrier is from 20 μm to 35 μm, and a quantity ratio of an elemental silicon derived from a silicone oil and an elemental silicon derived from silica which are present on the surface of the carrier is from 0.05 to 0.2.
WHITE DRY INK PULVERIZED TONER COMPOSITION AND FORMULATION THEREOF
An apparatus and method of manufacturing a white dry ink pulverized toner including a resin and 15%-45% TiO2 pigment having a mean size of 100-350 nm melt mixed with the resin in a twin screw extruder resulting in an extruded mix. The extruded mix is pulverized in a fluid bed jet mill. Fines of the pulverized extruded mix less than 5 microns may be removed from the pulverized extruded mix by classification leaving pulverized particles having a mean size of 6-12 microns. The pulverized particles are blended in a mixer with surface additives including silica and ZnSt, and the white dry ink pulverized toner has a developer charge between 5 and 50 μC/gram and a Lightness (L*) of at least 75 at a toner mass per unit area (TMA) of at most 1.2 mg/cm.sup.2.
TONER FORMULATIONS HAVING IMPROVED TONER USAGE EFFICIENCY
A toner composition having improved toner usage efficiency, wherein toner particles having an average size range of 1-25 μm may be mixed with an extra particulate additive package including a first small silica surface treated with both a silane and an aminosilane having a primary particle size of about 5 nm-20 nm, a second fumed silica having a primary particle size of 30 nm-60 nm, a third silica having a primary particle size of about 70 nm-120 nm, an electro-conductive titania having a primary particle size of 30 nm-60 nm and an acicular titania having a size of about 1.6 μm to 1.7 μm in length and about 130 nm in diameter. An alternative embodiment of the extra particulate additive package does not include a third silica having a primary particle size of about 70 nm-120 nm.
ELECTROPHOTOGRAPHIC MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS
The present invention provides an electrophotographic member which has a high ability to impart charge to toners while the charge imparting ability is unlikely to be reduced even under an environment at high temperature and high humidity.
The electrophotographic member comprises a substrate, an elastic layer formed on the substrate, an intermediate layer covering the surface of the elastic layer, and a surface layer covering the surface of the intermediate layer, wherein the intermediate layer contains a binder resin and a polymer having a specific structure, the surface layer contains silicon oxide, and the surface layer has a thickness of 10 nm or more and 300 nm or less.
TONER AND METHOD OF PRODUCING TONER
A toner comprising a toner particle containing a binder resin, a wax, and inorganic fine particles, wherein the binder resin contains a crystalline polyester resin and an amorphous polyester resin, and, in a cross section of the toner particle, when Sc represents an area taken up by the crystalline polyester resin and S1 represents an area taken up by the inorganic fine particles that are present in the crystalline polyester resin portion, Sc and S1 satisfy the relationship S1/Sc≧0.2.
ELECTROSTATIC CHARGE IMAGE DEVELOPING TONER, ELECTROSTATIC CHARGE IMAGE DEVELOPER, AND TONER CARTRIDGE
An electrostatic charge image developing toner includes: toner particles; first silica particles having an average circularity of 0.9 to 1.0, a particle size distribution index of 1.05 to 1.25, and a compression aggregation degree of 60% to 95%; and second silica particles having an average circularity of 0.9 to 1.0, a particle size distribution index of 1.05 to 1.25, and a compression aggregation degree of 60% to 95%, wherein, when an average primary particle diameter of the first silica particles is set as Da (nm) and an average primary particle diameter of the second silica particles is set as Db (nm), relationships of the following Expressions (A1) to (A3) are satisfied: Expression (A1): 80≦Da≦120, Expression (A2): 120≦Db≦200, and Expression (A3): 10≦Db−Da≦120.
Toner and imaging method
A toner having compatibility between transfer properties and cleaning properties is provided. A toner wherein a fine particle A containing a primary particle having a number average particle diameter (D1) of 80 nm or more and 400 nm or less is present on the surface of a toner particle at a coverage ratio of 5 to 40%, a fixing rate of 30 to 90% by mass, and a variation coefficient of 0.1 to 0.5 in a region of 0.5 πμm.sup.2.
IMAGE FORMING APPARATUS
Image forming apparatus, including: image bearer; charging unit for electrically charging image bearer surface; developing unit for developing with toner, electrostatic latent image formed over image bearer by exposure unit for performing light exposure; transfer unit for transferring developed toner to receiving member; and cleaning unit for cleaning toner remaining over image bearer without being transferred, wherein the toner contains: external additives; and base particles made of at least binder resin and colorant, external additive content of the toner is from 4 to 7 parts by mass relative to 100 parts by mass of base particles, primary particles of at least one external additive have a number average particle diameter of 0.01 to 0.05 μm, cleaning unit includes an elastic-body blade having surface elastic modulus of from 15 to 25 N/mm.sup.2 and surface friction coefficient of from 0.5 to 0.7 at an abutment part thereof abutting on image bearer.