DOWA IP CREATION CO., LTD. Patent applications |
Patent application number | Title | Published |
20150220014 | METHOD FOR MANUFACTURING CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - This invention is directed to a method for manufacturing carrier core particles for electrophotographic developer containing iron, manganese, and calcium as a core composition. The method includes (A) a mixing step of mixing an iron-containing raw material, a manganese-containing raw material, and a calcium-containing raw material to prepare a mixture thereof, (C) a granulation step of granulating the mixture after the mixing step, and (D) a firing step of firing a powdery material, which is obtained by granulating the mixture in the granulation step, at a predetermined temperature to form a magnetic phase. The calcium-containing raw material is provided in a granular form, and primary particles of the calcium-containing raw material have a volume mean diameter of 1 μm or less. | 08-06-2015 |
20150010462 | CARRIER CORE PARTICLE FOR ELECTROPHOTOGRAPHIC DEVELOPER, METHOD FOR MANUFACTURING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - A carrier core particle for an electrophotographic developer includes a composition expressed by a general formula: Mn | 01-08-2015 |
20140242511 | METHOD FOR MANUFACTURING CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - Provided is a method for manufacturing carrier core particles for electrophotographic developer capable of stably maintaining high chargeability over a long time. The method for manufacturing carrier core particles includes a granulation step of granulating a mixture of raw materials containing manganese, iron, strontium, and calcium and a firing step of firing the mixture granulated in the granulation step. The firing step includes a heating process of heating the granular mixture with an increase in temperature to a predetermined degree and a cooling process of cooling the granular mixture, after the heating process, in an atmosphere with an oxygen concentration ranging from 5000 ppm to 20000 ppm. The molar ratio of the sum of strontium and calcium to the sum of the manganese, iron, strontium, and calcium is 0.0026 to 0.013. | 08-28-2014 |
20140154623 | CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, ELECTROPHOTOGRAPHIC DEVELOPER AND METHOD FOR MANUFACTURING THE CARRIER CORE PARTICLES - The carrier core particles for electrophotographic developer include a core composition expressed by a general formula Fe | 06-05-2014 |
20140017609 | METHOD FOR MANUFACTURING CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - A method for manufacturing carrier core particles for electrophotographic developer including a slurrying step (A) of making an iron-containing raw material and a strontium-containing raw material into slurry, a granulation step (B) of granulating the slurry mixture obtained in the slurrying step, and a firing step (C) of firing a powdery material, which is obtained by granulating the slurry mixture in the granulation step, at a predetermined temperature to form a magnetic phase. The slurrying step makes the iron-containing raw material into the slurry containing the iron-containing raw material having a volume diameter D | 01-16-2014 |
20140017606 | FERRITE PARTICLES AND ELECTROPHOTOGRAPHIC CARRIER AND ELECTROPHOTOGRAPHIC DEVELOPER USING SAME - A material expressed as a composition formula M | 01-16-2014 |
20130344431 | CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - The carrier core particles for electrophotographic developer have a volume size distribution with a median particle size ranging from 30 μm to 40 μm, the ratio of the carrier core particles having a diameter of 22 μm or lower in the volume size distribution is from 1.0% to 2.0%, the ratio of the carrier core particles having a diameter of 22 μm or lower in a number size distribution is 10% or lower, and the magnetization of the carrier core particles in an external magnetic field of 1000 Oe is from 50 emu/g to 75 emu/g. | 12-26-2013 |
20130189614 | CARRIER CORE PARTICLE FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - A carrier core particle for an electrophotographic developer including a core composition expressed by a general formula: (Mn | 07-25-2013 |
20130084521 | CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, ELECTROPHOTOGRAPHIC DEVELOPER AND METHOD FOR MANUFACTURING THE CARRIER CORE PARTICLES - The carrier core particles for electrophotographic developer include a core composition expressed by a general formula Fe | 04-04-2013 |
20130011781 | CARRIER CORE PARTICLE FOR ELECTROPHOTOGRAPHIC DEVELOPER, METHOD FOR MANUFACTURING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - A carrier core particle for an electrophotographic developer includes a composition expressed by a general formula: Mn | 01-10-2013 |
20130011780 | CARRIER CORE PARTICLE FOR ELECTROPHOTOGRAPHIC DEVELOPER, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - A carrier core particle for an electrophotographic developer includes a core composition expressed by a general formula: Mn | 01-10-2013 |
20120295195 | CARRIER CORE PARTICLES FOR ELECTROPHOTOGRAPHIC DEVELOPER, METHOD FOR MANUFACTURING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - The carrier core particles | 11-22-2012 |
20120208121 | CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, METHOD FOR MANUFACTURING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER AND ELECTROPHOTOGRAPHIC DEVELOPER - A carrier core material for electrophotographic developer containing a soft ferrite, expressed by (Mg | 08-16-2012 |
20100086869 | CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER AND METHOD FOR PRODUCING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - To provide a carrier for two-component electrophotographic developer not only having excellent fluidity but also having proper surface irregularities necessary for imparting electric charge, without generating cracks/chipping of particles even under an influence of stirring stress over a long period of time. A particle surface has raised parts of striped pattern extending almost continuously in a plurality of directions while being superposed on one another, with a surface formed with raised parts of striped pattern occupying 80% or more of the whole surface of a particle. Depths of grooves between the adjacent raised parts are 0.05 μm or more and 0.2 μm or less, average surface roughness Ra is 0.1 μm or more and 0.3 μm or less, roundness is 0.90 or more, and average particle size is 151 μm or more and 100 μm or less, and a carrier core material thus constituted is coated with resin. Thus, the carrier for two-component electrophotographic developer is prepared. | 04-08-2010 |
20100075244 | CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND MANUFACTURING METHOD OF THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - To provide a carrier for electrophotographic developer, capable of realizing a high image quality and full colorization and reducing carrier scattering, and a manufacturing method of the same, and an electrophotographic developer containing the carrier. A carrier core material for electrophotographic developer, with a general formula expressed by Mg | 03-25-2010 |
20100035174 | CARRIER CORE MATERIAL FOR ELECTROPHOTOGRAPHIC DEVELOPER AND METHOD FOR PRODUCING THE SAME, CARRIER FOR ELECTROPHOTOGRAPHIC DEVELOPER, AND ELECTROPHOTOGRAPHIC DEVELOPER - To provide a carrier for an electrophotographic developer in which high image quality and full colorization are possible while carrier scattering is reduced, and a method for producing the carrier, and an electrophotographic developer including the carrier. A carrier core material for an electrophotographic developer is produced so that the half-value width B of a peak having a maximum intensity in an XRD pattern satisfies B≦0.160 (degree). A carrier for an electrophotographic developer and an electrophotographic developer are produced from the carrier core material for an electrophotographic developer. | 02-11-2010 |
20090110857 | OXYGEN ABSORBER FOR BLENDING IN A RESIN AND METHOD OF PRODUCING THE SAME - An oxygen absorber for blending in a resin, comprising a mixed powder containing an iron powder, a metal halide and an alkaline substance, and having a half-peak width on a plane (110) of 0.20°/2θ (Co—Kα) or less as measured by a powder X-ray diffraction method, a specific surface area of 0.5 m | 04-30-2009 |