Patents by Inventor Toshimasa Hamada
Toshimasa Hamada 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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Patent number: 11960038Abstract: A radiation dosimetry gel, usable in a polymer gel dosimeter having an improved sensitivity and high safety, includes a gelator, and a compound of the following Formula (1): wherein R1 is a hydrogen atom or a methyl group, m and n are each an integer of 2 to 4, k is 0 or 1, and a plurality of R1s and ms are each the same as or different from one another. Also provided for is a radiation dosimeter including the radiation dosimetry gel as a material for radiation dosimetry.Type: GrantFiled: May 18, 2020Date of Patent: April 16, 2024Assignees: RIKEN, NISSAN CHEMICAL CORPORATIONInventors: Takaoki Takanashi, Daniel Antonio Sahade, Toshimasa Hamada
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Publication number: 20220221594Abstract: There is provided a radiation dosimetry gel that is usable in a polymer gel dosimeter having an improved sensitivity and high safety. A radiation dosimetry gel comprising a gelator, and a compound of the following Formula (1): (wherein R1 is a hydrogen atom or a methyl group; m and n are each an integer of 2 to 4; k is 0 or 1; and plurality of R1s and ms are each the same as or different from one another) and a radiation dosimeter comprising the radiation dosimetry gel as a material for radiation dosimetry.Type: ApplicationFiled: May 18, 2020Publication date: July 14, 2022Applicants: RIKEN, NISSAN CHEMICAL CORPORATIONInventors: Takaoki TAKANASHI, Daniel Antonio SAHADE, Toshimasa HAMADA
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Patent number: 9002226Abstract: A developing device which includes a developing roller which supplies a toner to a photoreceptor and a supply roller which performs supply of a toner to the developing roller and peeling of a toner from the developing roller, and applies a bias voltage to the developing roller so as to develop an electrostatic latent image formed on the photoreceptor with a toner. The developing device includes a first current measuring portion which measures a value of a current flowing in the developing roller, a second current measuring portion which measures a value of a current flowing in the supply roller, and a control portion which calculates a toner charging amount on the developing roller and a toner peeled amount by the supply roller based on measured results by the first current measuring portion and the second current measuring portion.Type: GrantFiled: September 13, 2011Date of Patent: April 7, 2015Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Patent number: 8669367Abstract: To provide a method whereby a 2-azaadamantane can easily be obtained in good yield. A method for producing a 2-azaadamantane represented by the formula (1), which comprises cyclizing a compound represented by the following formula (2) in the presence of an acid.Type: GrantFiled: August 14, 2012Date of Patent: March 11, 2014Assignees: Nissan Chemical Industries, Ltd., Tohoku Techno Arch Co., Ltd.Inventors: Toshimasa Hamada, Noriaki Nagahama, Masami Kozawa, Yoshiharu Iwabuchi, Masatoshi Shibuya, Masaki Tomizawa, Yusuke Sasano
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Patent number: 8644741Abstract: Provided is a developing device employing single-component development in which in an upstream side of a most proximate area of a developing roller and a blade for regulating a toner layer, toner aggregation is made difficult to occur between the developing roller and the blade, and uniformity of the toner layer on the developing roller is increased, so as to be able to perform development which does not apply heavy stress and is excellent in uniformity. In the developing device, the blade is divided into two areas of a downstream area in a rotational direction of the developing roller including the most proximate part to the developing roller and an upstream area in a rotational direction of the developing roller not including the most proximate part, and adhesion between a toner and the blade in the upstream area is made smaller than that in the downstream area.Type: GrantFiled: August 16, 2011Date of Patent: February 4, 2014Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Publication number: 20120310005Abstract: To provide a method whereby a 2-azaadamantane can easily be obtained in good yield. A method for producing a 2-azaadamantane represented by the formula (1), which comprises cyclizing a compound represented by the following formula (2) in the presence of an acid.Type: ApplicationFiled: August 14, 2012Publication date: December 6, 2012Applicants: TOHOKU TECHNO ARCH CO., LTD., Nissan Chemical Industries, Ltd.Inventors: Toshimasa HAMADA, Noriaki NAGAHAMA, Masami KOZAWA, Yoshiharu IWABUCHI, Masatoshi SHIBUYA, Masaki TOMIZAWA, Yusuke SASANO
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Patent number: 8326195Abstract: A transfer device and an image forming apparatus capable of forming an image of smooth image quality with little uneven density, are provided. An alternating voltage is applied so that a first period in which a first peak-to-peak voltage Vpp(1) is applied and a second period in which a second peak-to-peak voltage Vpp(2), lower than the first peak-to-peak voltage, is applied are alternately repeated. In the alternating voltage to be applied, a transfer side potential to shift a toner from an intermediate transfer belt to recording paper sheet and an opposite transfer side potential to shift the toner from the recording paper sheet to the intermediate transfer belt are applied so as to alternate with each other. When f1 denotes a frequency of the first period and f2 denotes a frequency of the second period, f1=f2 is satisfied.Type: GrantFiled: May 27, 2010Date of Patent: December 4, 2012Assignee: Sharp Kabushiki KaishaInventors: Toyoka Aimoto, Toshimasa Hamada
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Patent number: 8273889Abstract: The invention provides a method for producing 2-azaadamantanes represented by formula (1) in good yields. The method includes cyclizing a compound represented by formula (2) in the presence of an acid.Type: GrantFiled: November 20, 2008Date of Patent: September 25, 2012Assignees: Nissan Chemical Industries, Ltd., Tohoku Techno Arch Co., Ltd.Inventors: Toshimasa Hamada, Noriaki Nagahama, Masami Kozawa, Yoshiharu Iwabuchi, Masatoshi Shibuya, Masaki Tomizawa, Yusuke Sasano
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Publication number: 20120070170Abstract: A developing device which includes a developing roller which supplies a toner to a photoreceptor and a supply roller which performs supply of a toner to the developing roller and peeling of a toner from the developing roller, and applies a bias voltage to the developing roller so as to develop an electrostatic latent image formed on the photoreceptor with a toner. The developing device includes a first current measuring portion which measures a value of a current flowing in the developing roller, a second current measuring portion which measures a value of a current flowing in the supply roller, and a control portion which calculates a toner charging amount on the developing roller and a toner peeled amount by the supply roller based on measured results by the first current measuring portion and the second current measuring portion.Type: ApplicationFiled: September 13, 2011Publication date: March 22, 2012Inventor: Toshimasa HAMADA
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Patent number: 8135295Abstract: There is provided an image forming apparatus capable of realizing Improvement of an image density by improving dot reproducibility and reducing fog as well. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp(1) is applied and a second period during which a second peak-to-peak voltage Vpp(2) that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other A frequency of the second period is lower than a frequency of the first period.Type: GrantFiled: June 22, 2009Date of Patent: March 13, 2012Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Publication number: 20120045255Abstract: Provided is a developing device employing single-component development in which in an upstream side of a most proximate area of a developing roller and a blade for regulating a toner layer, toner aggregation is made difficult to occur between the developing roller and the blade, and uniformity of the toner layer on the developing roller is increased, so as to be able to perform development which does not apply heavy stress and is excellent in uniformity. In the developing device, the blade is divided into two areas of a downstream area in a rotational direction of the developing roller including the most proximate part to the developing roller and an upstream area in a rotational direction of the developing roller not including the most proximate part, and adhesion between a toner and the blade in the upstream area is made smaller than that in the downstream area.Type: ApplicationFiled: August 16, 2011Publication date: February 23, 2012Applicant: SHARP KABUSHIKI KAISHAInventor: Toshimasa HAMADA
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Patent number: 7974545Abstract: A developing device capable of improving the image density and the dot reproducibility, and an image forming apparatus including the same are provided. A developing device applies an alternating voltage superimposed on a direct current voltage to a developing roller to thereby develop an electrostatic latent image formed on a photoreceptor with toner. A bias voltage waveform superimposed at this time has an original period (first period) in which each of a development-side electrical potential and an opposite development-side electrical potential is applied one time and a period (second period) in which a Vpp is gradually increased from the initial value to the maximum value.Type: GrantFiled: February 26, 2009Date of Patent: July 5, 2011Assignee: Sharp Kabushiki KaishaInventors: Toshimasa Hamada, Nobuhiro Maezawa
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Patent number: 7949270Abstract: In an embodiment in which an electrostatic latent image formed on the surface of a photoreceptor is developed with a toner by applying an oscillating bias voltage in which a development-side electrical potential and an opposite development-side electrical potential alternate with each other, between a development sleeve of a development roller and the photoreceptor, the development-side electrical potential is applied in two stages, and, in the two-staged development-side electrical potential, the absolute value of a first electrical potential V1 that is initially applied is larger than the absolute value of a second electrical potential V2 that is subsequently applied.Type: GrantFiled: December 12, 2007Date of Patent: May 24, 2011Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Patent number: 7899372Abstract: A developing device for an image forming apparatus includes both a layer height restricting blade for controlling a thickness of the developer layer on a developer supply roller, and a spike-height restricting blade. The spike-height restricting blade is located downstream from the layer height restricting blade, and upstream from the position at which an electrostatic latent image bearing member and the developer supply roller are closest to each other. Preferably, the tip of the spike-height restricting blade is located downstream from a radial line along which a main magnetic pole of the device projects half of its maximum magnetic field strength.Type: GrantFiled: December 31, 2008Date of Patent: March 1, 2011Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Patent number: 7890029Abstract: There is provided an image forming apparatus capable of realizing improvement of an image density by improving dot reproducibility and reducing fog at the same time. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp(1) is applied and a second period during which a second peak-to-peak voltage Vpp(2) that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other. The potential to be finally applied in the first period is preferably the development-side potential.Type: GrantFiled: June 10, 2009Date of Patent: February 15, 2011Assignee: Sharp Kabushiki KaishaInventor: Toshimasa Hamada
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Publication number: 20100311977Abstract: To provide a method whereby a 2-azaadamantane can easily be obtained in good yield. A method for producing a 2-azaadamantane represented by the formula (1), which comprises cyclizing a compound represented by the following formula (2) in the presence of an acid.Type: ApplicationFiled: November 20, 2008Publication date: December 9, 2010Applicants: Nissan Chemical Industries, Ltd., Tohoku Techno Arch Co., Ltd.Inventors: Toshimasa Hamada, Noriaki Nagahama, Masami Kozawa, Yoshiharu Iwabuchi, Masatoshi Shibuya, Masaki Tomizawa, Yusuke Sasano
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Publication number: 20100303518Abstract: A transfer device and an image forming apparatus capable of forming an image of smooth image quality with little uneven density, are provided. An alternating voltage is applied so that a first period in which a first peak-to-peak voltage Vpp(1) is applied and a second period in which a second peak-to-peak voltage Vpp(2), lower than the first peak-to-peak voltage, is applied are alternately repeated. In the alternating voltage to be applied, a transfer side potential to shift a toner from an intermediate transfer belt to recording paper sheet and an opposite transfer side potential to shift the toner from the recording paper sheet to the intermediate transfer belt are applied so as to alternate with each other. When f1 denotes a frequency of the first period and f2 denotes a frequency of the second period, f1=f2 is satisfied.Type: ApplicationFiled: May 27, 2010Publication date: December 2, 2010Inventors: Toyoka AIMOTO, Toshimasa Hamada
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Patent number: 7664440Abstract: A developing device and an image forming apparatus capable of restraining density irregularity and restraining a decline in image quality caused by adherence of carrier to a photoreceptor, are provided. An angle ? is in a range of no less than 45 degrees nor more than 57 degrees, which is formed between a plane comprising a central line of magnetic pole formed by a regulating pole in a magnet roller and a rotating central axis of a developing sleeve and a plane comprising a central line of magnetic pole formed by a pumping pole and a rotating central axis of the developing sleeve. Further, an absolute value of the maximum value of strength of the magnetic pole formed by a main pole is in a range of no less than 120 mT nor more than 140 mT.Type: GrantFiled: May 30, 2008Date of Patent: February 16, 2010Assignee: Sharp Kabushiki KaishaInventors: Nobuhiro Maezawa, Toshimasa Hamada
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Publication number: 20090317143Abstract: There is provided an image forming apparatus capable of realizing Improvement of an image density by improving dot reproducibility and reducing fog as well. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp(1) is applied and a second period during which a second peak-to-peak voltage Vpp(2) that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other A frequency of the second period is lower than a frequency of the first period.Type: ApplicationFiled: June 22, 2009Publication date: December 24, 2009Inventor: Toshimasa Hamada
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Publication number: 20090304414Abstract: There is provided an image forming apparatus capable of realizing improvement of an image density by improving dot reproducibility and reducing fog at the same time. An alternating voltage is applied to a development sleeve so that a first period during which a first peak-to-peak voltage Vpp(1) is applied and a second period during which a second peak-to-peak voltage Vpp(2) that is lower than the first peak-to-peak voltage is applied are repeated alternately. The alternating voltage to be applied is applied so that a development-side potential to move toner from the development sleeve to a photoreceptor and an opposite development-side potential to move toner from the photoreceptor to the development sleeve alternate with each other. The potential to be finally applied in the first period is preferably the development-side potential.Type: ApplicationFiled: June 10, 2009Publication date: December 10, 2009Inventor: Toshimasa Hamada