Kido Eiichi

Bio: Kido Eiichi is an academic researcher. The author has contributed to research in topics: Jet mill. The author has an hindex of 1, co-authored 1 publications receiving 89 citations.

Production of toner

Abstract: PURPOSE:To prevent the floating of magnetic powder from a toner surface by long-period agitation by forming a toner in such a manner that the magnetic powder is tightly adhered onto the surface of the electrostatically charged toner sticking onto the surface of a photosensitive drum. CONSTITUTION:A resin, coloring matter, etc. are measured and mixed. A synthetic resin is melted or softened by a heating kneader, etc., and the coloring matter, etc., are uniformly dispersed into the resin. The kneaded mixture is cooled to permit the easy crushing thereof and the cooled mixture is crushed to 1-3mm size by a hammer mill or cutter mill, etc.; further, the crushed mixture is pulverized to 3-50mum by using a jet mill. The powder of large grain sizes is removed and similarly the powder of very small grain sizes is removed in order to make the powder grain size (toner grain size) uniform. The toner is then put into a softened state by using a heating kneader, etc., and the magnetic powder having the grain size smaller than the toner grain size is added to such toner and is uniformly mixed therewith. The mixed toner is cooled in order to tightly adhere the magnetic powder thereto. The resultant toner has the magnetic powder tightly stuck to the surface.

Toner and image forming method

Abstract: A toner suitable for use in an image forming method including a contact charging step is provided. The toner includes: toner particles comprising at least a binder resin and a colorant, and fine particles. The fine particles comprise: (i) a tungsten-containing tin oxide, or (ii) base particles, and a tungsten-containing tin compound coating the base particles, the fine particles contain tin (Sn) in a weight ratio (Sn/b) of 0.01 to 2.0 with respect to the base particles (B). In the fine particles, tungsten (W) is contained in a mol ratio (W/Sn) of 0.001 to 0.3 with respect to the tin (Sn).

Toner, two-component developer and image forming method

Abstract: A toner is disclosed which has toner particles and an external additive. The toner has (a) in circularity distribution of particles measured with a flow type particle image analyzer, an average circularity of from 0.920 to 0.995, containing particles with a circularity of less than 0.950 in an amount of from 2% by number to 40% by number; and (b) a weight-average particle diameter of from 2.0 μm to 9.0 μm as measured by Coulter method. The external additive has, on the toner particles, at least (i) an inorganic fine powder (A) present in the state of primary particles or secondary particles and having an average particle length of from 10 mμm to 400 mμm and a shape factor SF-1 of from 100 to 130 and (ii) a non-spherical inorganic fine powder (B) formed by coalescence of a plurality of particles and having a shape factor SF-1 of greater than 150. Also, a two-component developer and an image forming method, using the toner, are disclosed.

Toner, toner production process and image forming method

Abstract: A toner having a good chargeability stable against an environmental change is formed of toner particles each comprising at least a binder resin, a colorant, a release agent and a sulfur-containing polymer, and an external additive. The toner particles contain 100 to 30,000 ppm by weight thereof of at least one stabilizer element selected from the group consisting of magnesium, calcium, barium, zinc, aluminum and phosphorus. The toner particles may preferably be produced by suspension polymerization of a monomer composition containing the sulfur-containing polymer in an aqueous medium containing a dispersion stabilizer having the stabilizer element.

Toner for developing electrostatic images, and process for producing the same

Abstract: A toner which comprises toner particles containing a binder resin, a colorant, a polar resin and a release agent, wherein the binder resin is a styrene polymer, a styrene copolymer, or a mixture of these, and has a weight average molecular weight Mw1 of from 10,000 to 1,000,000, the polar resin is a polyester resin containing a tetrahydrofuran-soluble matter of which weight average molecular weight Mw2 is from 7,000 to 50,000 and an ethyl alcohol-soluble matter of which weight average molecular weight Mw3 is from 1,000 to 7,000, where Mw2 /Mw3 is from 1.2 to 10.

Toner for developing electrostatic images and image forming method

Abstract: A toner for developing electrostatic images contains toner particles containing at least a binder resin and a colorant as well as a fine powder comprised of base particles on which crystalline low resistance tin oxide films are formed. The crystalline low resistance tin oxide contains less than 100 ppm of antimony, arsenic and phosphorus, and has an oxygen deficiency structure. The toner is excellent in strength and can consistently give high quality images under any environmental conditions.