摘要:
The carrier core particles 11 for electrophotographic developer contain lithium as a core composition. When the carrier core particles 11 are immersed in pure water at a weight ratio of 1 part core particles 11 to 10 parts pure water and shaken, the amount of lithium that leaches out to the pure water is 0.10 ppm or lower.
摘要:
The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical magnetic composite particles comprising a phenol resin as a binder and ferromagnetic iron oxide particles bonded to each other through the phenol resin, wherein the spherical magnetic composite particles have a ten-point mean roughness Rz of 0.3 to 2.0 µm. The magnetic carrier for an electrophotographic developer according to the present invention exhibits an excellent durability against peeling-off and abrasion of coating resins formed thereon and a high stability to mechanical stress exerted onto the carrier, is free from occurrence of spent toner, can be stably held over a long period of time without occurrence of fogging and unevenness in density of toner images, and can keep high-quality images with an excellent gradation for a long period of time.
摘要:
The present invention relates to a magnetic carrier for an electrophotographic developer comprising spherical composite particles comprising spherical composite core particles comprising at least ferromagnetic iron oxide fine particles and a cured phenol resin and having an average particle diameter of 1 to 100 µm, and a melamine resin coating layer formed on the respective core particles, wherein a ratio of R 100 to R 300 (R 100 /R 300 ) in which R 100 is an electric resistance value as measured when applying a voltage of 100 V to the magnetic carrier; and R 300 is an electric resistance value as measured when applying a voltage of 300 V to the magnetic carrier, is controlled to lie within the range of 1 to 50. The magnetic carrier according to the present invention is capable of maintaining an adequate electric resistance value upon development, providing images having an excellent image quality, exhibiting a good durability, obtaining a good reproducibility of uniform solid image portions having a high image density, and keeping high quality images having an excellent gradation for a long period of time.
摘要:
An electrophotographic developer comprising a carrier and a magnetic toner, the magnetic toner containing a cycloolefin copolymer resin as a binder resin. The carrier is preferably one wherein the surface of core particles is coated with a resin coating agent, or a magnetic substance dispersion type resin carrier. When the saturation magnetization of carrier at an external magnetic field of 5 kOe is referred to as Sc, it is preferred that the saturation magnetization of magnetic toner at an external magnetic field of 5 kOe (St) satisfy the relationship: 0.10 Sc ≤ St ≤ 0.40 Sc. The electrophotographic developer excels in environmental characteristics, enables maintaining satisfactory image density at continuous copying of a multiplicity of sheets, is free from fogging and toner scattering problems, and can reduce the amount of toner consumed.
摘要:
There is provided a resin-coated carrier for an electrophotographic developer, including: a carrier core particle; and a coating resin layer comprising a silicone resin or a modified silicone resin formed on a surface of the carrier core particle, wherein a titanium-ethyl acetoacetate chelate or a titanium-octylene glycol chelate is contained in the coating resin layer as a titanium chelate, and wherein the content of the titanium-ethyl acetoacetate chelate or the titanium-octylene glycol chelate is 5.0 to 50.0% by weight based on coating resin solids. There is also provided an electrophotographic developer using the resin-coated carrier.
摘要:
L'invention concerne un procédé de matage formant motif sur un produit verrier dans lequel le produit est revêtu d'une couche masquant les parties non-attaquées de la surface, le matage des parties non-masquées et l'élimination de la couche de masquage, dans lequel la couche de masquage est obtenue par une technique xerographique (électrophotographique) dans laquelle : - un motif est digitalisé et mémorisé ; - le motif en question est reproduit sur une surface sensible soumise à un champ électrique ; - la surface sensible dont la surface est sélectivement activée est revêtue par une composition pulvérulente de toner, comportant des constituants électriquement chargeables et un matériau de revêtement protecteur fusible ; - la composition pulvérulente adhère sélectivement aux parties activées de la surface sensible ; - la composition adhérant à la surface sensible est transférée sur l'objet en verre à revêtir préalablement chauffé faisant fondre cette composition formant une couche qui adhère à l'objet en verre.
摘要:
Provided is a two-component developer containing: a magnetic carrier obtained by coating a magnetic core with a resin; and toner, in which: the magnetic core contains at least a ferrite component and at least one kind of an oxide selected from the group consisting of SiO 2 and Al 2 O 3 ; the content of the oxide is 4.0 mass% or more and 40.0 mass% or less with respect to the magnetic core; the magnetic core has a specific resistance of 5. O×10 4 Ω⋅cm or more and 5. O×10 8 Ω⋅cm or less at the time of the application of 1,000 V/cm; the magnetic carrier has an intensity of magnetization in 79.6 kA/m of 40.0 Am 2 /kg or more and 65.0 Am 2 /kg or less, and a residual magnetization after the application of an external magnetic field of 79.6 kA/m of 3.0 Am 2 /kg or less; and the toner has a weight-average particle diameter (D4 ) of 3.0 μm or more and 10.0 μm or less and an average circularity.of 0.940 or more and 0.990 or less.