Patents Assigned to Yamanashi Electronics Co., Ltd.
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Patent number: 8263297Abstract: An electrophotographic photoconductor including a conductive support and a photosensitive layer, wherein the photosensitive layer contains a charge generation agent, a charge transport agent and a binder resin, and wherein the charge generation agent contains an asymmetric disazo pigment represented by General Formula (I), the charge transport agent contains a triphenylamine compound represented General Formula (IX), and the mass ratio of the charge transport agent to the binder resin is 0.3 to 2.0, where R1 and R2 each represent a substituted or unsubstituted alkyl group, alkoxy group, aryl group or heterocyclic group, provided that R1 and R2 are different, where R3 to R5 each represent hydrogen, a halogen atom, an alkyl group having 1 to 6 carbon atoms, which may have a substituent, an alkoxy group having 1 to 6 carbon atoms, which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.Type: GrantFiled: November 25, 2008Date of Patent: September 11, 2012Assignees: Ricoh Company, Ltd., Yamanashi Electronics Co., Ltd.Inventors: Takaaki Ikegami, Takeshi Takada, Toshihiko Koizumi, Hideki Nakamura, Hajime Suzuki, Keisuke Shimoyama, Kohsuke Yamamoto, Eiji Kurimoto
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Patent number: 7811738Abstract: In an image forming method including a charging step, an exposure step, a development step using a developing roll, a transfer step, a fixing step and a cleaning step of removing a toner remaining on the surface of a photosensitive member after the transfer step, the developing roll has a surface brightness of 30 to 220 and a surface roughness Rz of 1 to 20 ?m, the cleaning blade is a cleaning blade made of a polyurethane elastomer and having a peak value of at most 0.95, a peak temperature of ?15 to 10° C. and a width at half maximum of at least 25° C. in viscoelasticity tan ?, the toner has a volume average particle diameter of 4 to 10 ?m and an average circularity from 0.950 to 0.995, the charge level of the toner on the surface of the photosensitive member is 10 to 80 ?C/g in terms of an absolute value, and the pH of a water extract of the toner is 3 to 8.Type: GrantFiled: May 31, 2005Date of Patent: October 12, 2010Assignees: Zeon Corporation, Toyo Tire & Rubber Co., Ltd., Yamanashi Electronics Co., Ltd., Shin-Etsu Polymer Co., Ltd.Inventors: Kazunori Shigemori, Muneharu Ito, Toshiyuki Nagai, Toshiro Murano, Fuminori Tsuruta, Tomoharu Takeuchi, Masahiro Ikeda, Sokuei Motoda
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Patent number: 7704655Abstract: An electrophotographic photoreceptor which can respond to a reduction in diameter of photoreceptor and a process having high circumferential speed, due to the demand in the miniaturization and increase in the speed of copiers and printers. The photoreceptor has high sensitivity in long-wavelength region, and is free from deterioration of electric characteristics even after repeated use, and is highly stable. The electrophotographic photoreceptor has a conductive support member and a photosensitive layer laminated thereon, which includes at least a charge-generating agent, a charge-transfer agent, and a binder resin. The charge-generating agent is oxytitanium phthalocyanine, which has a Bragg angle (2?±0.2°) providing a maximum peak at 27.2° in the X-ray diffraction spectra using CuK? as a radiation source.Type: GrantFiled: July 30, 2008Date of Patent: April 27, 2010Assignees: Yamanashi Electronics Co., Ltd., Ricoh Company, Ltd.Inventors: Hajime Suzuki, Tsuyoshi Ueda, Toshihiko Koizumi, Hideki Nakamura, Tetsuya Sakuma
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Patent number: 7629096Abstract: An electrophotographic photoreceptor that without detriment to excellent electrophotographic performance, realizes coating of any defects on a conductive substrate and excels in repetition stability and environmental performance. There is provided an electrophotographic photoreceptor having a photoreceptive layer superimposed via an undercoat layer on a conductive support, characterized in that the undercoat layer contains a polyimide resin and that at least one of the compounds of the following formulae is contained as a charge transfer agent of the photoreceptive layer.Type: GrantFiled: December 21, 2004Date of Patent: December 8, 2009Assignee: Yamanashi Electronics Co., Ltd.Inventors: Hajime Suzuki, Tadayoshi Uchida, Ryoji Kobayashi
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Publication number: 20090136260Abstract: An electrophotographic photoconductor including a conductive support and a photosensitive layer, wherein the photosensitive layer contains a charge generation agent, a charge transport agent and a binder resin, and wherein the charge generation agent contains an asymmetric disazo pigment represented by General Formula (I), the charge transport agent contains a triphenylamine compound represented General Formula (IX), and the mass ratio of the charge transport agent to the binder resin is 0.3 to 2.0, where R1 and R2 each represent a substituted or unsubstituted alkyl group, alkoxy group, aryl group or heterocyclic group, provided that R1 and R2 are different, where R3 to R5 each represent hydrogen, a halogen atom, an alkyl group having 1 to 6 carbon atoms, which may have a substituent, an alkoxy group having 1 to 6 carbon atoms, which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.Type: ApplicationFiled: November 25, 2008Publication date: May 28, 2009Applicants: RICOH COMPANY, LTD,, YAMANASHI ELECTRONICS CO., LTD.Inventors: Takaaki IKEGAMI, Takeshi Takada, Toshihiko Koizumi, Hideki Nakamura, Hajime Suzuki, Keisuke Shimoyama, Kohsuke Yamamoto, Eiji Kurimoto
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Publication number: 20090004585Abstract: An electrophotographic photoreceptor which can respond to a reduction in diameter of photoreceptor and a process having high circumferential speed, due to the demand in the miniaturization and increase in the speed of copiers and printers. The photoreceptor has high sensitivity in long-wavelength region, and is free from deterioration of electric characteristics even after repeated use, and is highly stable. The electrophotographic photoreceptor has a conductive support member and a photosensitive layer laminated thereon, which includes at least a charge-generating agent, a charge-transfer agent, and a binder resin. The charge-generating agent is oxytitanium phthalocyanine, which has a Bragg angle (2?±0.2°) providing a maximum peak at 27.2° in the X-ray diffraction spectra using CuK? as a radiation source.Type: ApplicationFiled: July 30, 2008Publication date: January 1, 2009Applicants: YAMANASHI ELECTRONICS CO., LTD., RICOH COMPANY, LTD.Inventors: Hajime Suzuki, Tsuyoshi Ueda, Toshihiko Koizumi, Hideki Nakamura, Tetsuya Sakuma
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Publication number: 20070217820Abstract: In an image forming method including a charging step, an exposure step, a development step using a developing roll, a transfer step, a fixing step and a cleaning step of removing a toner remaining on the surface of a photosensitive member after the transfer step, the developing roll has a surface brightness of 30 to 220 and a surface roughness Rz of 1 to 20 ?m, the cleaning blade is a cleaning blade made of a polyurethane elastomer and having a peak value of at most 0.95, a peak temperature of ?15 to 10° C. and a width at half maximum of at least 25° C. in viscoelasticity tan ?, the toner has a volume average particle diameter of 4 to 10 ?m and an average circularity from 0.950 to 0.995, the charge level of the toner on the surface of the photosensitive member is 10 to 80 ?C/g in terms of an absolute value, and the pH of a water extract of the toner is 3 to 8.Type: ApplicationFiled: May 31, 2005Publication date: September 20, 2007Applicants: ZEON CORPORATION, TOYO TIRE & RUBBER CO., LTD., YAMANASHI ELECTRONICS CO., LTD., SHIN-ETSU POLYMER CO., LTD.Inventors: Kazunori Shigemori, Muneharu Ito, Toshiyuki Nagai, Toshiro Murano, Fuminori Tsuruta, Tomoharu Takeuchi, Masahiro Ikeda, Sokuei Motoda
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Patent number: 7195851Abstract: A photosensitive layer contains an electron-transfer agent that makes use of a compound represented by the following general formula (1): wherein R1 through R4 are each independently selected from the group consisting of hydrogen, cyano, nitro, halogen, hydroxyl, alkyl, aryl, heterocyclic ring, ester, alkoxy, aralkyl, allyl, amide, amino, acyl, alkenyl, alkynyl, carboxyl, carbonyl, and carboxylic acid; X is selected from the group consisting of oxygen, sulfur, and ?C(CN)2; and W is a 4- to 8-membered ring.Type: GrantFiled: November 30, 2005Date of Patent: March 27, 2007Assignees: Yamanashi Electronics Co., Ltd., Permachem Asia, Ltd.Inventors: Yasuyuki Kiuchi, Toyozoh Satoh, Hitoshi Takahashi, Hiroki Suzuki, Mitsuyo Momose
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Publication number: 20060134539Abstract: A photosensitive layer contains an electron-transfer agent that makes use of a compound represented by the following general formula (1): wherein R1 through R4 are each independently selected from the group consisting of hydrogen, cyano, nitro, halogen, hydroxyl, alkyl, aryl, heterocyclic ring, ester, alkoxy, aralkyl, allyl, amide, amino, acyl, alkenyl, alkynyl, carboxyl, carbonyl, and carboxylic acid; X is selected from the group consisting of oxygen, sulfur, and ?C(CN)2; and W is a 4- to 8-membered ring.Type: ApplicationFiled: November 30, 2005Publication date: June 22, 2006Applicants: PERMACHEM ASIA, SHINDENGEN ELECTRIC MANUFACTURING CO., LTD., YAMANASHI ELECTRONICS CO., LTD.Inventors: Yasuyuki Kiuchi, Toyozoh Satoh, Hitoshi Takahashi, Hiroki Suzuki, Mitsuyo Momose
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Publication number: 20040142261Abstract: A photosensitive layer contains an electron-transfer agent that makes use of a compound represented by the following general formula (1): 1Type: ApplicationFiled: September 30, 2003Publication date: July 22, 2004Applicants: PERMACHEM ASIA, LTD., SHINDENGEN ELECTRIC MANUFACTURING CO., LTD., YAMANASHI ELECTRONICS CO., LTD.Inventors: Yasuyuki Kiuchi, Toyozoh Satoh, Hitoshi Takahashi, Tomoko Kitsunai, Hiroki Suzuki, Mitsuyo Momose
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Patent number: 6642534Abstract: It is an object of the invention to improve the quality of images obtained by an X-ray detector. A charge transport layer 13 mainly consisted of diantimony trisulfide, an X-ray detection layer 14 mainly consisted of amorphous selenium and a second electrode film 15 are formed in the same order on the surface of a first electrode film 12 provided on a substrate 11. A voltage whose polarity is positive at the first electrode film 12 and negative at the second electrode film 15 is applied, and the surface of the second electrode film 15 is irradiated with an X-ray. Then, carriers generated in the X-ray detection layer 14 are collected by the first and second electrode films.Type: GrantFiled: March 23, 2001Date of Patent: November 4, 2003Assignees: Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd., Shimadzu CorporationInventors: Kazuhiko Shima, Masahito Sato, Naoki Uchida, Yoichiro Shimura, Kenji Sato, Hidetoshi Kishimoto
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Patent number: 6495817Abstract: A carrier selective high resistance film is formed over an entire area between a thick amorphous semiconductor layer and a voltage application electrode, and an electrodeless region extends throughout a circumference of the voltage application electrode. As a result, dark currents are suppressed, without impairing signal response characteristics, by carrier selectivity of the carrier selective high resistance film. Covered by the carrier selective high resistance film, the thick amorphous semiconductor layer maintains an effective surface resistance. The electrodeless region extending circumferentially of the voltage application electrode secures a sufficient surface voltage endurance to suppress creeping discharges due to a bias voltage. Consequently, sufficient detection sensitivity is secured by applying a high bias voltage to the voltage application electrode.Type: GrantFiled: August 16, 2000Date of Patent: December 17, 2002Assignees: Shimadzu Corporation, Shindengen Electric Manufacturing Co., Ltd, Yamanashi Electronics Co., Ltd.Inventors: Kenji Sato, Masahito Sato
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Patent number: 6280893Abstract: Electrophotographic photoreceptors for use in photocopiers and laser printers, among other things, possessing high electron mobility and superior photosensitivity properties. The photoreceptors of the invention utilize a photosensitive layer with a carrier transport material containing a compound which exhibits high molecular vibration. The compounds of the invention are electron transfer agents which can be dispersed in a photosensitive layer at a high concentration and can be molecularly designed to have a desired magnitude of molecular vibration.Type: GrantFiled: March 3, 1999Date of Patent: August 28, 2001Assignees: Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd.Inventors: Mitsuyo Takano, Hiroki Suzuki
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Patent number: 5876892Abstract: An electrophotographic photoreceptor in which the surface of a photosensitive layer has a small friction coefficient without impairing the excellent electrophotographic characteristics and which has an enhanced oil resistance and does not cause light fatigue, the electrophotographic photoreceptor comprising an electroconductive support having formed thereon a photosensitive layer comprising at least a charge-generating agent, a charge-transfer agent and a binder resin, wherein the photosensitive layer contains a polycarbonate copolymer comprising a recurring unit represented by the general formula (I) as the binder resin: ##STR1## and a butadiene compound represented by the general formula (IV) as the charge-transfer agent: ##STR2##Type: GrantFiled: June 4, 1998Date of Patent: March 2, 1999Assignees: Shindengen Electric Manufacturing Co., LTD, Yamanashi Electronics Co., LTD.Inventors: Kenichi Fujimori, Yoshitaro Nakayama, Mitsuru Noro, Tetsuya Sakuma, Hajime Suzuki
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Patent number: 5494766Abstract: An electrophotographic photoreceptor which is excellent in various properties, has effectively inhibited photo-induced fatigue and has stability against repeated use, and which comprises an electroconductive support and a photosensitive layer comprising as essential components a charge-generating material and a diaminodiphenyl compound represented by the general formula (I): ##STR1##Type: GrantFiled: November 16, 1994Date of Patent: February 27, 1996Assignees: Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd.Inventors: Kazuhito Dohi, Hajime Suzuki
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Patent number: 5443933Abstract: An electrophotographic photoreceptor which is highly sensitive to light having a wavelength in the oscillatory wavelength region of semiconductor laser and responds quickly and is excellent in other electrophotographic characteristics and which consists an electroconductive support, a charge-generating layer and a charge-transfer layer, the two layers being placed on the support, and said charge-transfer layer containing a specific butadiene compound having formula (I); ##STR1## and a monophenol type antioxidant, the weight ratio of the monophenol type antioxidant/the butadiene compound ranging from 5/95 to 40/80.Type: GrantFiled: September 10, 1993Date of Patent: August 22, 1995Assignees: Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd., Takasago International CorporationInventors: Kenichi Fujimori, Yoshitaro Nakayama, Takumi Shinohara, Atsushi Iwanami, Toshimitsu Hagiwara, Tohru Kobayashi
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Patent number: 5399453Abstract: The invention provides an electrophotographic photoreceptor excellent in various characteristics, especially effectively protected from light fatigue and stable against repeated use. The photoreceptor comprises an electroconductive substrate having placed thereon a photosensitive layer which contains a bisazo compound of the formula [I]: ##STR1## a diamine derivative of the formula [IV]: ##STR2## and a specific amount of a phenolic antioxidant, and the photoreceptor contains, if necessary, an intermediate layer between the electroconductive substrate and the photosensitive layer.Type: GrantFiled: March 4, 1994Date of Patent: March 21, 1995Assignees: Yamanashi Electronics Co., Ltd., Shindengen Electric Manufacturing Co., Ltd.Inventors: Kazuhito Dohi, Hajime Suzuki, Tetsushi Shiozawa, Yoichi Watanabe
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Patent number: 5263517Abstract: A toner pack for use with the developing device includes a toner box in which toner is stored and which is detachably set at the developing device, an endless seal sheet a portion of which is peelably bonded to the toner box to cover an opening of the toner box, a flat cylindrical cover member through which that portion of the endless seal sheet which does not cover the opening of the toner box is freely movably passed, and a pull portion which is freely movably passed through the cover member and one end of which is made continuous from the endless seal sheet.Type: GrantFiled: April 15, 1992Date of Patent: November 23, 1993Assignees: Kabushiki Kaisha Toshiba, Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd.Inventors: Takashi Ishikawa, Jiro Fukasawa, Shinji Tsuji
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Patent number: 5188057Abstract: A developing apparatus including a hopper storing toner and carrier and a roller disposed in an opening of the hopper. A carrier stopper is provided on a front wall of the hopper proximate the opening having an arced surface concentrically opposing an upper portion of the roller. Thus, a blend layer volume is formed in a first space between the carrier stopper and the roller for storing a blended layer of carrier and toner such that the carrier stopper prevents carrier from scattering outside the blend layer volume and the conjunctional effect of rotating the roller and of the magnetic force of the rotary magnets in the roller blends the carrier and toner stored in the blended layer. A sub-hopper, proximate the blend layer volume, is also formed by a second space between the carrier stopper and a lateral bottom wall of the hopper for storing toner to be provided to the blended layer.Type: GrantFiled: September 17, 1990Date of Patent: February 23, 1993Assignees: Kabushiki Kaisha Toshiba, Shindengen Electric Manufacturing Co., Ltd., Yamanashi Electronics Co., Ltd.Inventors: Masaaki Ishikawa, Michihisa Iguchi, Hiroshi Hashizume, Yasuo Fujii, Tetsuya Nakamura, Hirotaka Fukuyama, Seiji Arai, Koichiro Sato, Toshio Takagi, Shuji Nishina, Jiro Hukasawa, Masatoshi Maruta, Seiichi Koizumi
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Patent number: 5181071Abstract: An apparatus for evaluating the characteristics of a photosensitive drum for use in electrophotography including a rotatable photosensitive drum having characteristics to be measured, a charging portion and an exposure light source portion and the like respectively secured to portions adjacent to the photosensitive drum. The surface potential of the photosensitive drum, which is generated due to operation of the charging portion and the exposure light source portion or the like, is measured by a potential measuring probe which is, together with the charged portion and the exposure light source portion and the like, secured adjacent to a position of the photosensitive drum, at which light is applied at the shortest distance from the exposure light source portion. The photosensitive drum is moved along its lengthwise direction so that the surface potential of the photosensitive drum is measured by the potential measuring probe.Type: GrantFiled: December 2, 1991Date of Patent: January 19, 1993Assignees: Yamanashi Electronics Co., Ltd., Shindengen Electric Manufacturing Co., Ltd.Inventors: Satoshi Nakajima, Kouichi Mochizuki, Hiroki Kobayashi, Yuji Kohno