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Koh Ishigami, Mishima-Shi JP

Koh Ishigami, Mishima-Shi JP

Patent application numberDescriptionPublished
20080286668TWO-COMPONENT DEVELOPER, REPLENISHING DEVELOPER, AND IMAGE-FORMING METHOD - An object of the present invention is to provide a two-component developer which can achieve a high-definition image with a smaller toner laid-on level than a conventional one, provides a color gamut comparable to that of printing, can respond to an increase in printing speed, and allows an image with a stable tinge to be formed even in long-term use. The object can be achieved by a two-component developer containing a cyan toner and a magnetic carrier, the two-component developer being characterized in that the cyan toner has the following characteristics: (i) when the concentration of the cyan toner in a solution of the cyan toner in chloroform is represented by Cc (mg/ml) and the absorbance of the solution at a wavelength of 712 nm is represented by A712, a relationship between Cc and A712 satisfies the relationship of 2.0011-20-2008
20090047592TONER - An object of the present invention is to provide a toner which: is excellent in fixing ability such as low-temperature fixability, hot offset property, and separability even in a fixing system excellent in quick start property and energy saving property; has high gloss; and is excellent in development stability and transferability irrespective of environments. The toner of the present invention includes toner particles each containing at least a binder resin and a colorant, in which, in a case where a tetrahydrofuran (THF) insoluble matter of the binder resin in the toner when the toner is subjected to Soxhlet extraction with THF for 2 hours is represented by A (mass %), a THF insoluble matter of the binder resin in the toner when the toner is subjected to Soxhlet extraction with THF for 4 hours is represented by B (mass %), a THF insoluble matter of the binder resin in the toner when the toner is subjected to Soxhlet extraction with THF for 8 hours is represented by C (mass %), and a THF insoluble matter of the binder resin in the toner when the toner is subjected to Soxhlet extraction with THF for 16 hours is represented by D (mass %), A, B, C, and D satisfy the following expression: (A−B)/2>(B−C)/4>(C−D)/8 where 4002-19-2009
20100028796MAGNETIC CARRIER AND TWO-COMPONENT DEVELOPER - A magnetic carrier and two-component developer are provided alleviating coarse images, fogging when printing is done after a copier body is left standing for one week in a high temperature and high humidity environment and carrier adhesion after extensive operation in a low image ratio. The magnetic carrier includes magnetic carrier particles including porous magnetic core particles and a resin, wherein in a mercury intrusion method applied to the porous magnetic core particles, a pore diameter in which a differential pore volume in the specific pore diameter range becomes maximum is in a specific range, and when the maximum value of a differential pore volume in the specific pore diameter range is defined as P1 and the maximum value of a differential pore volume in the specific pore diameter range is defined as P2, P1 is in a specific range and the ratio P2/P1 is in a specific range.02-04-2010
20100119967MAGNETIC CARRIER AND TWO-COMPONENT DEVELOPER - A magnetic carrier and a two-component developer are provided which have remedied blank areas, fog after leaving, carrier sticking during running, and image density variations before and after running. The magnetic carrier has magnetic carrier particles having at least porous magnetic core particles and a resin. The magnetic carrier particles satisfying the specific conditions (a), (b) and (c) where, in a reflected electron image of cross sections of the magnetic carrier particles as photographed with a scanning electron microscope, straight lines that divide a cross section of a magnetic carrier particle into 72 at intervals of 5° are drawn from a reference point of the cross section thereof toward the surface of the magnetic carrier particle; the magnetic carrier particles being contained in an amount of 60% by number or more.05-13-2010
20100119968MAGNETIC CARRIER AND TWO COMPONENT DEVELOPER - Provided is a magnetic carrier giving a high quality image free of density variation without the occurrence of fogging or carrier adhesion and having excellent dot reproducibility even during long-term use. The magnetic carrier has magnetic carrier particles produced by filling pores of porous magnetic core particles with a resin. The magnetic carrier contains 80% by number or more of the magnetic carrier particles satisfying the specific conditions (a) and (b) when 18 straight lines passing through a reference point of a cross section of the magnetic carrier particle are drawn at intervals of 10° in a reflected electron image of the cross section of the magnetic carrier particle photographed by a scanning electron microscope.05-13-2010
20100136473MAGNETIC CARRIER AND TWO-COMPONENT DEVELOPER - A magnetic carrier which has magnetic carrier particles each having at least porous magnetic core particles and a resin, in which, in a backscattered electron image of the magnetic carrier particles, photographed with a scanning electron microscope as taken at an accelerating voltage of 2.0 kV, magnetic carrier particles having area proportion S06-03-2010
20100143833MAGNETIC CARRIER, TWO-COMPONENT DEVELOPER AND IMAGE FORMING METHOD - A magnetic carrier is provided which uses a toner having high coloring power and enables development to be performed at low electric field intensity and can form high quality images while keeping gradation characteristics. The magnetic carrier includes magnetic carrier particles including at least porous magnetic core particles and a resin. The electric field intensity just before the break-down of the magnetic carrier is 1,300 V/cm or more and 5,000 V/cm or less.06-10-2010
20100159380TWO-COMPONENT DEVELOPER, REPLENISHING DEVELOPER, AND IMAGE-FORMING METHOD - A two-component developer containing a cyan toner and a magnetic carrier, wherein the cyan toner has the characteristics: (i) when the concentration of the cyan toner in a solution of the cyan toner in chloroform is represented by Cc (mg/ml) and the absorbance of the solution at a wavelength of 712 nm is represented by A712, a relationship between Cc and A712 satisfies the relationship of 2.0006-24-2010
20100159382ELECTROPHOTOGRAPHIC DEVELOPMENT CARRIER, TWO-COMPONENT DEVELOPER AND IMAGE-FORMING METHOD USING THE TWO-COMPONENT DEVELOPER - A carrier has an impedance Z having a frequency dependence, obtained by alternating current impedance measurement. When the frequency dependence is fitted by a fitting function, parameter α lies in a range of 0.70 to 0.90 in an electric field of 1006-24-2010
20100183971MAGNETIC CARRIER, TWO-COMPONENT DEVELOPER AND IMAGE FORMING METHOD - A magnetic carrier having magnetic carrier particles each containing at least a magnetic core particle and a resin; the magnetic carrier having a resistivity of from 1.0×1007-22-2010
20100203438TWO-COMPONENT DEVELOPER, REPLENISHING DEVELOPER, AND IMAGE-FORMING METHOD - A two-component developer containing a yellow toner and a magnetic carrier, wherein the yellow toner has the characteristics: (i) when the concentration of the yellow toner in a solution of the yellow toner in chloroform is represented by Cy (mg/ml) and the absorbance of the solution at a wavelength of 422 nm is represented by A08-12-2010
20100248126TWO-COMPONENT DEVELOPER, REPLENISHING DEVELOPER, AND IMAGE-FORMING METHOD - A two-component developer containing a magenta toner and a magnetic carrier, wherein the magenta toner has the characteristics: (i) when the concentration of the magenta toner in a solution of the magenta toner in chloroform is represented by Cm (mg/ml) and the absorbance of the solution at a wavelength of 538 nm is represented by A538, a relationship between Cm and A538 satisfies the relationship of 2.0009-30-2010
20100273103MAGNETIC CARRIER AND TWO-COMPONENTS DEVELOPER - The present invention provides an image of high image quality by using a magnetic carrier coated with a novel coating resin composition. Further, the present invention stably provides a good image which is hardly influenced by environmental fluctuation and long-term use and has a superior stability of a charging amount when left to stand especially under high temperature and high humidity environments. The present invention also provides a magnetic carrier characterized in that a carrier core surface is coated with a copolymer containing at least, as copolymerization components, an acrylic monomer having a specific structure and an acrylic macromonomer having a specific structure.10-28-2010
20100279224METHOD FOR PRODUCING ELECTROPHOTOGRAPHIC CARRIER AND ELECTROPHOTOGRAPHIC CARRIER PRODUCED BY USING THE METHOD - In a method for coating electrophotographic carrier core surfaces with a resin composition by rotating a rotator having a plurality of agitating blades on its surface in a casing; a coating treatment material that is introduced to a space defined between the rotator and the casing is in a packing of from 50% to 98% by volume; at the time of coating treatment, the electrophotographic carrier core surfaces are coat-treated with the resin composition while being put forward and put backward; and the electrophotographic carrier cores and the resin composition are, at the time of coating treatment, temperature-controlled at a specific temperature T (° C.) or below. This method enables the electrophotographic carrier core surfaces to be more uniformly coated with a coating resin.11-04-2010
20100310978TWO-COMPONENT DEVELOPER - 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 SiO12-09-2010
20110024669PRODUCTION METHOD OF MAGNETIC CARRIER AND MAGNETIC CARRIER PRODUCED THEREWITH - When a surface of magnetic carrier core particles is coated with coating resin composition particles, the coating is conducted so that a surface of the magnetic carrier is free from cracks and chips and has fewer residual resin composition particles and a coating is uniform. In the method, a rotor having a plurality of stirring members on a surface thereof is rotated to coat the surface of magnetic carrier core particles with the resin composition particles. When the coating is conducted, while repeatedly conducting transportation in a direction of a driver and transportation in an anti-driver direction, the surface of the magnetic carrier core particles is coated with the resin composition. The resin composition particles has a 50% particle diameter (D02-03-2011
20110097661TWO-COMPONENT DEVELOPER, REPLENISHING DEVELOPER, AND IMAGE-FORMING METHOD - An object of the present invention is to provide a two-component developer which can achieve a high-definition image with a smaller toner laid-on level than a conventional one, provides a color gamut comparable to that of printing, can respond to an increase in printing speed, and allows an image with a stable tinge to be formed even in long-term use. The object can be achieved by a two-component developer containing a cyan toner and a magnetic carrier, the two-component developer being characterized in that the cyan toner has the following characteristics: (i) when the concentration of the cyan toner in a solution of the cyan toner in chloroform is represented by Cc (mg/ml) and the absorbance of the solution at a wavelength of 712 nm is represented by A712, a relationship between Cc and A712 satisfies the relationship of 2.0004-28-2011
20110111337MAGNETIC CARRIER - In the formation of images by a two-component development system, provided is a magnetic carrier that can be used to output an image which has sufficient density, in which few white spots are present in a low-density portion located near the boundary between a high-density region and a low-density region, and in which the low-density portion has good graininess. The magnetic carrier contains magnetic carrier particles each of which has resin and a magnetic particle. The magnetic particle contains ferrite phases and phases comprising a perovskite-structured compound. The ferrite phases and phases comprising a perovskite-structured compound are combined.05-12-2011
20110143277TONER, BINARY DEVELOPER, AND IMAGE FORMING METHOD - It is an object of the present invention to provide a toner having the transfer efficiency and the cleanability in combination, exhibiting excellent stress resistance, and ensuring the low-temperature fixing.06-16-2011

Patent applications by Koh Ishigami, Mishima-Shi JP