Patents by Inventor Maki Okajima
Maki Okajima 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).
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Publication number: 20210132519Abstract: A toner includes a toner particle containing a binder resin and an inorganic infrared absorbent particle, wherein (1) in spectrometry of a fixed image obtained by fixing an unfixed image formed on a recording material by using the toner in a loading amount of 0.30 mg/cm2, a maximum value of a light absorbance in a wavelength range of 400 nm or more and 800 nm or less is 10% or less, and (2) in cross section observation of the toner particle using a transmission electron microscope, when a circle having the center of gravity of a cross section image of the toner particle as the center thereof and having a radius of 2.0 ?m is drawn and the circle is divided into four to form four quadrants, a coefficient of variation in number of the inorganic infrared absorbent particles observed in each quadrant is 0.50 or less.Type: ApplicationFiled: December 31, 2020Publication date: May 6, 2021Inventors: Akira Hashimoto, Takeshi Yamamoto, Ryuji Higashi, Takayuki Toyoda, Maki Okajima, Akiko Kitao, Koichi Suzuki
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Patent number: 10151990Abstract: A toner comprising a toner particle that contains a binder resin, wherein the surface of the toner particle is covered with a resin A; the modulus of elasticity Ea of the resin A and the modulus of elasticity Eb of the binder resin satisfy the following formula: 0.5?(Ea/Eb)×100?50.0; and the adhesion force AT of the toner particle is at least 500 nN when a probe having spherical SiO2 attached at the tip of a cantilever is pressed into the toner particle at 3 ?N.Type: GrantFiled: November 16, 2017Date of Patent: December 11, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Masao Suzuki, Kazuyuki Sato, Shohei Fukuya, Atsushi Nakamoto, Makoto Fukatsu, Takahiro Kawamoto, Maki Okajima, Masayoshi Kato, Yasunori Chigono, Takeshi Yamamoto
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Publication number: 20180149989Abstract: A toner comprising a toner particle that contains a binder resin, wherein the surface of the toner particle is covered with a resin A; the modulus of elasticity Ea of the resin A and the modulus of elasticity Eb of the binder resin satisfy the following formula: 0.5?(Ea/Eb)×100?50.0; and the adhesion force AT of the toner particle is at least 500 nN when a probe having spherical SiO2 attached at the tip of a cantilever is pressed into the toner particle at 3 ?N.Type: ApplicationFiled: November 16, 2017Publication date: May 31, 2018Inventors: Masao Suzuki, Kazuyuki Sato, Shohei Fukuya, Atsushi Nakamoto, Makoto Fukatsu, Takahiro Kawamoto, Maki Okajima, Masayoshi Kato, Yasunori Chigono, Takeshi Yamamoto
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Patent number: 9705087Abstract: Provided is an organic light emitting device with enhanced durability during continuous driving. The organic light emitting device includes: an anode, a cathode, and an organic compound layer being placed between the anode and the cathode and including at least a hole transport layer and an emission layer, in which: the emission layer contains a blue light emitting material; the hole transport layer contains a plurality of kinds of organic compounds; and an organic compound having the smallest ionization potential among the organic compounds includes a compound having no absorption spectrum peak in a blue color wavelength region in a radical cation state.Type: GrantFiled: February 25, 2016Date of Patent: July 11, 2017Assignee: CANON KABUSHIKI KAISHAInventors: Minako Nakasu, Masataka Yashima, Hajime Muta, Keiji Okinaka, Tomona Yamaguchi, Tomonari Horikiri, Maki Okajima, Naoki Yamada
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Publication number: 20160181528Abstract: Provided is an organic light emitting device with enhanced durability during continuous driving. The organic light emitting device includes: an anode, a cathode, and an organic compound layer being placed between the anode and the cathode and including at least a hole transport layer and an emission layer, in which: the emission layer contains a blue light emitting material; the hole transport layer contains a plurality of kinds of organic compounds; and an organic compound having the smallest ionization potential among the organic compounds includes a compound having no absorption spectrum peak in a blue color wavelength region in a radical cation state.Type: ApplicationFiled: February 25, 2016Publication date: June 23, 2016Inventors: MINAKO NAKASU, MASATAKA YASHIMA, HAJIME MUTA, KEIJI OKINAKA, TOMONA YAMAGUCHI, TOMONARI HORIKIRI, MAKI OKAJIMA, NAOKI YAMADA
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Patent number: 9331296Abstract: Aspects of the present invention provide a blue organic light-emitting device having a continuous operation lifetime. An organic light-emitting device includes a light-emitting layer containing a dopant having the ability to trap electrons or holes, and a hole-blocking layer or electron-blocking layer, in which the difference between the LUMO of the dopant and the LUMO of a host material, the size relationship between the HOMO of the host material and the HOMO of the dopant, and the difference between the T1 of the host material and the T1 of the hole-blocking layer or between the T1 of the host material and the T1 of the electron-blocking layer, are specified.Type: GrantFiled: March 14, 2011Date of Patent: May 3, 2016Assignee: Canon Kabushiki KaishaInventors: Maki Okajima, Keiji Okinaka, Tetsuo Takahashi, Hajime Muta, Yohei Iwasaki, Minako Nakasu, Naoki Yamada, Yosuke Nishide
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Patent number: 9312494Abstract: Provided is an organic light emitting device with enhanced durability during continuous driving. The organic light emitting device includes: an anode, a cathode, and an organic compound layer being placed between the anode and the cathode and including at least a hole transport layer and an emission layer, in which: the emission layer contains a blue light emitting material; the hole transport layer contains a plurality of kinds of organic compounds; and an organic compound having the smallest ionization potential among the organic compounds includes a compound having no absorption spectrum peak in a blue color wavelength region in a radical cation state.Type: GrantFiled: December 2, 2010Date of Patent: April 12, 2016Assignee: Canon Kabushiki KaishaInventors: Minako Nakasu, Masataka Yashima, Hajime Muta, Keiji Okinaka, Tomona Yamaguchi, Tomonari Horikiri, Maki Okajima, Naoki Yamada
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Patent number: 9115055Abstract: A novel fluorenylamine compound represented by a general formula below, where R1 to R6 are each independently selected from a hydrogen atom and alkyl groups; R21 to R23 are each independently selected from a hydrogen atom and the alkyl groups; and the alkyl groups are a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.Type: GrantFiled: October 18, 2010Date of Patent: August 25, 2015Assignee: Canon Kabushiki KaishaInventors: Tomonari Horikiri, Naoki Yamada, Maki Okajima, Minako Nakasu
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Patent number: 8624231Abstract: A benzopyrene compound represented by a general formula [1] below, where one of X1 and X2 represents a substituted or unsubstituted aryl group; another one of X1 and X2 represents a hydrogen atom; R represents an alkyl group; and n represents 0 or 1.Type: GrantFiled: March 30, 2011Date of Patent: January 7, 2014Assignee: Canon Kabushiki KaishaInventors: Naoki Yamada, Yosuke Nishide, Maki Okajima, Tetsuo Takahashi, Jun Kamatani, Akihito Saitoh
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Patent number: 8354788Abstract: An organic light emitting device having long continuous driving lifetime is provided. The organic light emitting device includes an anode, a cathode, and an emission layer formed of an organic compound arranged between the anode and the cathode, in which the emission layer includes a light emitting material and a material having a smallest ionization potential, and an absorption spectrum in a radical cation state of the material having the smallest ionization potential in the emission layer does not have its absorption peak in an emission wavelength region of the light emitting material.Type: GrantFiled: May 14, 2009Date of Patent: January 15, 2013Assignee: Canon Kabushiki KaishaInventors: Keiji Okinaka, Masataka Yashima, Maki Okajima, Hajime Muta
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Publication number: 20130001542Abstract: Aspects of the present invention provide a blue organic light-emitting device having a continuous operation lifetime. An organic light-emitting device includes a light-emitting layer containing a dopant having the ability to trap electrons or holes, and a hole-blocking layer or electron-blocking layer, in which the difference between the LUMO of the dopant and the LUMO of a host material, the size relationship between the HOMO of the host material and the HOMO of the dopant, and the difference between the T1 of the host material and the T1 of the hole-blocking layer or between the T1 of the host material and the T1 of the electron-blocking layer, are specified.Type: ApplicationFiled: March 14, 2011Publication date: January 3, 2013Applicant: CANON KABUSHIKI KAISHAInventors: Maki Okajima, Keiji Okinaka, Tetsuo Takahashi, Hajime Muta, Yohei Iwasaki, Minako Nakasu, Naoki Yamada, Yosuke Nishide
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Patent number: 8299459Abstract: The present invention provides an organic light emitting device which shows a blue light emission hue of remarkably good color purity and has a high-efficiency and high-luminance optical output.Type: GrantFiled: September 28, 2010Date of Patent: October 30, 2012Assignee: Canon Kabushiki KaishaInventors: Maki Okajima, Naoki Yamada
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Publication number: 20120211742Abstract: A novel fluorenylamine compound represented by a general formula below, where R1 to R6 are each independently selected from a hydrogen atom and alkyl groups; R21 to R23 are each independently selected from a hydrogen atom and the alkyl groups; and the alkyl groups are a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.Type: ApplicationFiled: October 18, 2010Publication date: August 23, 2012Applicant: CANON KABUSHIKI KAISHAInventors: Tomonari Horikiri, Naoki Yamada, Maki Okajima, Minako Nakasu
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Publication number: 20120205639Abstract: Provided is an organic light emitting device with enhanced durability during continuous driving. The organic light emitting device includes: an anode, a cathode, and an organic compound layer being placed between the anode and the cathode and including at least a hole transport layer and an emission layer, in which: the emission layer contains a blue light emitting material; the hole transport layer contains a plurality of kinds of organic compounds; and an organic compound having the smallest ionization potential among the organic compounds includes a compound having no absorption spectrum peak in a blue color wavelength region in a radical cation state.Type: ApplicationFiled: December 2, 2010Publication date: August 16, 2012Applicant: CANON KABUSHIKI KAISHAInventors: Minako Nakasu, Masataka Yashima, Hajime Muta, Keiji Okinaka, Tomona Yamaguchi, Tomonari Horikiri, Maki Okajima, Naoki Yamada
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Publication number: 20120132901Abstract: An organic light-emitting device includes an anode, a cathode, and an organic compound layer interposed between the anode and the cathode. The organic compound layer contains a pyrene derivative.Type: ApplicationFiled: July 23, 2010Publication date: May 31, 2012Applicant: CANON KABUSHIKI KAISHAInventors: Naoki Yamada, Jun Kamatani, Maki Okajima, Ryota Ooishi, Akihito Saitoh
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Publication number: 20110240976Abstract: A benzopyrene compound represented by a general formula [1] below, where one of X1 and X2 represents a substituted or unsubstituted aryl group; another one of X1 and X2 represents a hydrogen atom; R represents an alkyl group; and n represents 0 or 1.Type: ApplicationFiled: March 30, 2011Publication date: October 6, 2011Applicant: CANON KABUSHIKI KAISHAInventors: Naoki Yamada, Yosuke Nishide, Maki Okajima, Tetsuo Takahashi, Jun Kamatani, Akihito Saitoh
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Publication number: 20110204349Abstract: The present invention provides an organic light emitting device which shows a blue light emission hue of remarkably good color purity and has a high-efficiency and high-luminance optical output.Type: ApplicationFiled: September 28, 2010Publication date: August 25, 2011Applicant: CANON KABUSHIKI KAISHAInventors: Maki Okajima, Naoki Yamada
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Patent number: 7982213Abstract: A novel phenanthroline compound is provided which is represented by the general formula [I]: (wherein R1, R2, R3, R4, R5 and R6 are the same or different and each is selected from a hydrogen atom, an unsubstituted or substituted alkyl group, an unsubstituted or substituted aralkyl group, an unsubstituted or substituted aryl group, an unsubstituted or substituted heterocyclic group, and a halogen atom; and Ar1 and Ar2 are the same or different and each is selected from an unsubstituted or substituted fluorenyl group, an unsubstituted or substituted fluoranthenyl group, an unsubstituted or substituted perylenyl group, and an unsubstituted or substituted carbazolyl group). An organic light emitting device using the phenanthroline compound is also provided that has a light output with a high efficiency and a high luminance and has a high long-term durability.Type: GrantFiled: May 6, 2009Date of Patent: July 19, 2011Assignee: Canon Kabushiki KaishaInventors: Maki Okajima, Tatsundo Kawai, Takao Takiguchi, Koichi Suzuki, Akihiro Senoo, Toshinori Hasegawa, Keiji Okinaka
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Publication number: 20110001864Abstract: An organic light emitting device having long continuous driving lifetime is provided. The organic light emitting device includes an anode, a cathode, and an emission layer formed of an organic compound arranged between the anode and the cathode, in which the emission layer includes a light emitting material and a material having a smallest ionization potential, and an absorption spectrum in a radical cation state of the material having the smallest ionization potential in the emission layer does not have its absorption peak in an emission wavelength region of the light emitting material.Type: ApplicationFiled: May 14, 2009Publication date: January 6, 2011Applicant: CANON KABUSHIKI KAISHAInventors: Keiji Okinaka, Masataka Yashima, Maki Okajima, Hajime Muta
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Publication number: 20100327274Abstract: An organic blue-light-emitting device having a high emission efficiency and a long continuous driving lifetime is provided. An organic light-emitting device 20 includes an anode 2, a cathode 5, and a stacked body which is interposed between the anode 2 and the cathode 5 and includes at least a layer which forms a light-emitting region (emission layer 6).Type: ApplicationFiled: March 31, 2009Publication date: December 30, 2010Applicant: CANON KABUSHIKI KAISHAInventors: Maki Okajima, Akihito Saitoh, Masumi Itabashi, Masanori Muratsubaki, Naoki Yamada, Hiroki Ohrui, Chika Negishi, Tetsuya Kosuge, Takayuki Horiuchi, Takeshi Sekiguchi, Hiroyuki Tomono