Patents by Inventor Keiji MAKABE

Keiji MAKABE has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20150212442
    Abstract: A toner is provided. The toner includes mother toner particles. Each mother toner particle includes a binder resin and inorganic-layer-containing resin particles. Each inorganic-layer-containing resin particle includes a resin particle and an inorganic layer on the surface of the resin particle.
    Type: Application
    Filed: January 28, 2015
    Publication date: July 30, 2015
    Inventors: Masayuki ISHII, Toyoshi SAWADA, Keiji MAKABE
  • Patent number: 9012116
    Abstract: A toner including a binder resin having a glass transition temperature (Tg) observed at least at one point from 25 to 65° C. in a differential scanning calorimeter at a rate of temperature increase of 5° C./min, wherein the toner has a structure in which a structure appearing as a high phase difference image is dispersed in a structure appearing as a low phase difference image in a two-dimensional phase difference image observed by tapping mode AFM, and an X-ray diffraction chart in which a peak originated from an crystalline resin is observed in a range of a diffraction angle 2? of from 20 to 25°, and wherein a ratio (I1/I2) of an intensity of the peak originated from an crystalline resin to an intensity (I2) of a halo originated from an amorphous composition is from 0.2 to 1.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: April 21, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Daiki Yamashita, Yoshihiro Moriya, Yukiko Nakajima, Taichi Nemoto, Yoshitaka Yamauchi, Keiji Makabe, Masahide Yamada, Suzuka Amemori
  • Publication number: 20150072287
    Abstract: A toner is provided. The toner includes a crosslinked polyester resin, and a block copolymer. The crosslinked polyester resin includes a diol component, which includes an aliphatic diol component having 3 to 10 carbon atoms in an amount of 50% by mole, and a crosslinked component, which is at least one of a crosslinked component of an aliphatic alcohol having three or more valences and a crosslinked component of an aliphatic acid having three or more valences, and the block copolymer includes a crystalline segment (a) and a non-crystalline segment (b). The toner has a first glass transition temperature (Tg1st) of from 20° C. to 50° C., which is determined by subjecting the toner to differential scanning calorimetry (DSC) and measuring a glass transition temperature in a first temperature rising process in the differential scanning calorimetry (DSC).
    Type: Application
    Filed: August 28, 2014
    Publication date: March 12, 2015
    Inventors: Suzuka AMEMORI, Tsuyoshi SUGIMOTO, Akinori SAITO, Toyoshi SAWADA, Keiji MAKABE
  • Patent number: 8932790
    Abstract: The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from ?20° C. to 20° C., and a second glass transition temperature of from 35° C. to 65° C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5° C./min.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: January 13, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshitaka Yamauchi, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita, Suzuka Amemori, Akiyoshi Sabu
  • Publication number: 20140342284
    Abstract: An electrophotographic toner including: a binder resin, wherein the binder resin has one glass transition temperature Tg and the glass transition temperature Tg of the binder resin is within 25° C. to 65° C. as measured in second heating with a differential scanning calorimeter at a heating rate of 5° C./min, and wherein a phase image of the binder resin obtained with an atomic force microscope (AFM) of tapping mode contains first phase difference regions and a second phase difference region such that the first phase difference regions are dispersed in the second phase difference region, where the first phase difference regions correspond to greater phase difference regions and the second phase difference region corresponds to a smaller phase difference region when an intermediate value between a maximum value and a minimum value of the phase differences is used as a threshold.
    Type: Application
    Filed: September 12, 2012
    Publication date: November 20, 2014
    Inventors: Yoshihiro Moriya, Masahide Yamada, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Keiji Makabe, Daiki Yamashita, Suzuka Amemori, Akiyoshi Sabu
  • Patent number: 8859179
    Abstract: A developer, including a toner including a binder resin comprising a crystalline resin; and a colorant, and a resin carrier comprising a resin; a magnetic particulate material having a magnetic anisotropy, dispersed in the resin, and having a saturated magnetization of from 16 to 30 emu/g, a coercive force of from 15 to 40 kA/m and an average particle diameter not less than 15 ?m and less than 100 ?m.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: October 14, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideyuki Santo, Masahide Yamada, Kazumi Suzuki, Shinya Nakayama, Atsushi Yamamoto, Tatsuya Morita, Shingo Sakashita, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita
  • Publication number: 20140272698
    Abstract: Toner contains a binder resin containing two or more kinds of crystalline resins; and a coloring agent, wherein the two or more kinds of crystalline resins have at least two endothermic peak temperatures in a set of endothermic peak temperatures of the two or more kinds of crystalline resins as measured by differential scanning calorimetry (DSC).
    Type: Application
    Filed: March 14, 2014
    Publication date: September 18, 2014
    Inventors: Masahide YAMADA, Atsushi Yamamoto, Satoyuki Sekiguchi, Keiji Makabe, Kohsuke Nagata, Toyoshi Sawada
  • Patent number: 8758973
    Abstract: An apparatus for producing a toner, including a liquid droplet-forming unit configured to discharge a toner composition liquid containing at least a resin and a colorant at a uniform discharge speed from a plurality of discharge holes some of which have different shapes from each other to thereby form liquid droplets, and a particle-forming unit configured to solidify the liquid droplets of the toner composition liquid to thereby form particles.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: June 24, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiji Makabe, Yohichiroh Watanabe, Minoru Masuda, Yasutada Shitara, Yoshihiro Norikane
  • Patent number: 8735040
    Abstract: To provide a toner including at least a binder resin and a colorant, wherein the binder resin has two glass transition temperatures Tg1 and Tg2 in a differential scanning calorimetry at a heating speed of 5° C./min, the glass transition temperature Tg1 is ?20° C. to 20° C., and the glass transition temperature Tg2 is 35° C. to 65° C., wherein the binder resin comprises a polyester skeleton and a ring-containing skeleton molecule at ends thereof, and wherein the binder resin is obtained by block copolymerization of: a polyester skeleton A which includes a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure; and a skeleton B which does not include a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: May 27, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Suzuka Amemori, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu
  • Patent number: 8685604
    Abstract: A toner including a colorant and a first binder resin is provided. The first binder resin has first and second glass transition points at a temperature Tg1 of ?20 to 20° C. and a temperature Tg2 of 35 to 65° C., respectively, measured by a differential scanning calorimeter at a heating rate of 5° C./min. A ratio h1/h2 of a baseline displacement h1 observed in the first glass transition point to a baseline displacement h2 observed in the second glass transition point is less than 1.0. The first binder resin has a structure in which a first phase is dispersed in a second phase. The first and second phases consist of portions having larger and smaller phase difference values, respectively, than an intermediate value between maximum and minimum phase difference values in a binarized phase image obtained by an atomic force microscope with a tapping mode method.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: April 1, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Moriya, Masahide Yamada, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu, Suzuka Amemori
  • Publication number: 20140080051
    Abstract: To provide a toner (X), which contains toner particles, each toner particle contains: a core phase (Q) containing a crystalline resin (A); and a shell phase (S) provided on a surface of the core phase (Q), where the shell phase (S) contains a crystalline polyurethane resin (B), wherein maximum peak temperature (Ta) of heat of melting of the crystalline resin (A) is 40° C. to 70° C., and maximum peak temperature (Tu) of heat of melting of the crystalline polyurethane resin (B) is 50° C. to 90° C.
    Type: Application
    Filed: September 17, 2013
    Publication date: March 20, 2014
    Inventors: Toyoshi SAWADA, Masahide YAMADA, Atsushi YAMAMOTO, Tatsuya MORITA, Satoyuki SEKIGUCHI, Keiji MAKABE, Kousuke NAGATA
  • Publication number: 20140051019
    Abstract: Toner contains a binder resin containing a crystalline resin having a urethane and/or urea bonding; and a colorant, wherein in a diffraction spectrum of the toner as measured by an X-ray diffraction instrument, a ratio {C/(C+A)} of an integral intensity C of the spectrum derived from the crystalline structure to an integral intensity A of the spectrum derived from the non-crystalline structure is 0.12 or greater, wherein the toner satisfies the following relation 1: T1?T2?30° C. (Relation 1), where T1 represents the maximum endothermic peak in the first temperature rising from 0° C. to 100° C. at the temperature rising rate of 10° C./min and T2 represents the maximum exothermic peak in the first temperature falling from 100° C. to 0° C. at the temperature falling rate of 10° C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).
    Type: Application
    Filed: August 5, 2013
    Publication date: February 20, 2014
    Inventors: Satoyuki Sekiguchi, Hiroshi Yamashita, Minoru Masuda, Susumu Chiba, Tatsuya Morita, Atsushi Yamamoto, Shinya Nakayama, Masahide Yamada, Kohsuke Nagata, Keiji Makabe, Toyoshi Sawada
  • Patent number: 8652744
    Abstract: A method for producing toner particles by ejecting a liquid from at least one ejection hole to form the liquid into liquid droplets, and solidifying the liquid droplets to produce toner particles. The ejecting is accomplished by applying a vibration to the liquid in a liquid column resonance-generating liquid chamber in which an ejection hole is formed to form a standing wave through liquid column resonance, and ejecting the liquid from the ejection hole which is formed in a region corresponding to an antinode of the standing wave to thereby form the liquid into the liquid droplets. Toner produced by the method.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: February 18, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Watanabe Yohichiroh, Yoshihiro Norikane, Yasutada Shitara, Keiji Makabe
  • Publication number: 20130244167
    Abstract: A toner including a binder resin having a glass transition temperature (Tg) observed at least at one point from 25 to 65° C. in a differential scanning calorimeter at a rate of temperature increase of 5° C./min, wherein the toner has a structure in which a structure appearing as a high phase difference image is dispersed in a structure appearing as a low phase difference image in a two-dimensional phase difference image observed by tapping mode AFM, and an X-ray diffraction chart in which a peak originated from an crystalline resin is observed in a range of a diffraction angle 2? of from 20 to 25°, and wherein a ratio (I1/I2) of an intensity of the peak originated from an crystalline resin to an intensity (I2) of a halo originated from an amorphous composition is from 0.2 to 1.
    Type: Application
    Filed: January 31, 2013
    Publication date: September 19, 2013
    Inventors: Daiki YAMASHITA, Yoshihiro Moriya, Yukiko Nakajima, Taichi Nemoto, Yoshitaka Yamauchi, Keiji Makabe, Masahide Yamada, Suzuka Amemori
  • Publication number: 20130236826
    Abstract: A toner for electrophotography, which is prepared by a method including dissolving or dispersing a toner composition including at least a binder resin, or binder resin and a binder resin precursor as a resin component; and a colorant in an organic solvent to form an oil phase; emulsifying or dispersing the oil phase in an aqueous medium to form an emulsion dispersion comprising emulsified particles; converging the emulsified particles to granulate mother toner particles, including controlling a temperature of the emulsion dispersion to control a circularity of the mother toner particles; and removing the organic solvent, wherein the resin component includes a crystalline resin in an amount not less than 50% by weight, and the mother toner particles have an average circularity of from 0.940 to 0.980.
    Type: Application
    Filed: December 10, 2012
    Publication date: September 12, 2013
    Inventors: Keiji MAKABE, Masahide Yamada, Shinya Nakayama, Atsushi Yamamoto, Hideyuki Santo, Yukiko Nakajima, Daiki Yamashita, Kazumi Suzuki, Tatsuya Morita, Shingo Sakashita
  • Publication number: 20130202996
    Abstract: The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from ?20° C. to 20° C., and a second glass transition temperature of from 35° C. to 65° C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5° C./min.
    Type: Application
    Filed: December 17, 2012
    Publication date: August 8, 2013
    Inventors: Yoshitaka Yamauchi, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita, Suzuka Amemori, Akiyoshi Sabu
  • Publication number: 20130171550
    Abstract: To provide a toner including at least a binder resin and a colorant, wherein the binder resin has two glass transition temperatures Tg1 and Tg2 in a differential scanning calorimetry at a heating speed of 5° C./min, the glass transition temperature Tg1 is ?20° C. to 20° C., and the glass transition temperature Tg2 is 35° C. to 65° C., wherein the binder resin comprises a polyester skeleton and a ring-containing skeleton molecule at ends thereof, and wherein the binder resin is obtained by block copolymerization of: a polyester skeleton A which includes a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure; and a skeleton B which does not include a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure.
    Type: Application
    Filed: December 27, 2012
    Publication date: July 4, 2013
    Inventors: Suzuka Amemori, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu
  • Publication number: 20130157183
    Abstract: A developer, including a toner including a binder resin comprising a crystalline resin; and a colorant, and a resin carrier comprising a resin; a magnetic particulate material having a magnetic anisotropy, dispersed in the resin, and having a saturated magnetization of from 16 to 30 emu/g, a coercive force of from 15 to 40 kA/m and an average particle diameter not less than 15 ?m and less than 100 ?m.
    Type: Application
    Filed: November 16, 2012
    Publication date: June 20, 2013
    Inventors: Hideyuki Santo, Masahide Yamada, Kazumi Suzuki, Shinya Nakayama, Atsushi Yamamoto, Tatsuya Morita, Shingo Sakashita, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita
  • Publication number: 20130149642
    Abstract: To provide a toner, which contains a first binder resin, and a second binder resin, wherein the first binder resin is a block polymer containing at least a polyester skeleton A having, in a repeating structure thereof, a constitutional unit formed by dehydration condensation of hydroxycarboxylic acid, and a skeleton B that does not have, in a repeating structure thereof, a constitutional unit formed by dehydration condensation of hydroxycarboxylic acid, and the first binder resin has glass transition temperature Tg1 and Tg 2 as measured by differential scanning calorimetry at a heating rate of 5° C./min, wherein the Tg1 is ?20° C. to 20° C., and the Tg2 is 35° C. to 65° C., and wherein the second binder resin is a crystalline resin.
    Type: Application
    Filed: November 20, 2012
    Publication date: June 13, 2013
    Inventors: Akiyoshi SABU, Yoshihiro MORIYA, Taichi NEMOTO, Yoshitaka YAMAUCHI, Yukiko NAKAJIMA, Keiji MAKABE, Suzuka AMEMORI, Daiki YAMASHITA, Masahide YAMADA
  • Publication number: 20130065172
    Abstract: A toner including a colorant and a first binder resin is provided. The first binder resin has first and second glass transition points at a temperature Tg1 of ?20 to 20° C. and a temperature Tg2 of 35 to 65° C., respectively, measured by a differential scanning calorimeter at a heating rate of 5° C./min. A ratio h1/h2 of a baseline displacement h1 observed in the first glass transition point to a baseline displacement h2 observed in the second glass transition point is less than 1.0. The first binder resin has a structure in which a first phase is dispersed in a second phase. The first and second phases consist of portions having larger and smaller phase difference values, respectively, than an intermediate value between maximum and minimum phase difference values in a binarized phase image obtained by an atomic force microscope with a tapping mode method.
    Type: Application
    Filed: September 11, 2012
    Publication date: March 14, 2013
    Inventors: Yoshihiro MORIYA, Masahide YAMADA, Taichi NEMOTO, Yukiko NAKAJIMA, Yoshitaka YAMAUCHI, Daiki YAMASHITA, Keiji MAKABE, Akiyoshi SABU, Suzuka AMEMORI