Patents by Inventor Haruo Iimura
Haruo Iimura 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: 20130148993Abstract: An image forming apparatus includes a nip forming member and a transfer bias output device that outputs a transfer bias to form a transfer electric field in a transfer nip between the nip forming member and an intermediate transfer member. Upon transfer of a composite toner image including a particular toner image onto a recording medium in the transfer nip, the transfer bias output device outputs the transfer bias including a first superimposed bias in which a direct current (DC) component is superimposed on an alternating current (AC) component. Upon transfer of the composite toner image without the particular toner image onto the recording medium in the transfer nip, the transfer bias output device outputs one of the transfer bias including a second superimposed bias having a peak-to-peak value of the AC component smaller than that of the first superimposed bias and the transfer bias including only the DC component.Type: ApplicationFiled: November 30, 2012Publication date: June 13, 2013Inventors: Shinji Aoki, Haruo Iimura, Yasuhiko Ogino, Tadashi Kasai, Naomi Sugimoto, Shinya Tanaka, Keigo Nakamura
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Publication number: 20120237234Abstract: An image forming apparatus includes an image carrier to carry a toner image, a transfer member to form a transfer nip by contacting the image carrier surface, and a power supply to output a voltage to the recording material captured in the transfer nip so as to transfer the toner image formed on the image carrier surface. The voltage is switching alternately between a voltage in the transfer direction and a voltage opposite to the voltage in the transfer direction, and a time average value (Vave) of the voltage is set to have a polarity of the transfer direction, and is set to a value in the transfer voltage side, and a change mode to change a cycle of the voltage output from the power supply can be changed based on the toner deterioration information which determines the deterioration status of the toner.Type: ApplicationFiled: March 5, 2012Publication date: September 20, 2012Inventors: Naomi SUGIMOTO, Shinya Tanaka, Haruo Iimura, Shinji Aoki, Yasuhiko Ogino, Keigo Nakamura
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Publication number: 20120230715Abstract: According to an embodiment, a transfer device includes: an image carrier from which an image is transferred onto a transfer medium using electrostatic toner, the image carrier being applied with a direct current voltage superimposed with an alternating current (AC) voltage as a transfer bias. An output voltage of a power source for applying the voltage is controlled so that a current level of a direct current component output from the power source is kept at a specified current level.Type: ApplicationFiled: February 27, 2012Publication date: September 13, 2012Inventors: Yasuhiko OGINO, Haruo Iimura, Shinji Aoki, Keigo Nakamura, Masahide Nakaya, Tomokazu Takeuchi, Shinya Tanaka
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Patent number: 8165481Abstract: An image forming method includes detecting a toner degradation state by detecting an image density on an electrostatic latent image carrier with high sensitivity and low cost. The degraded toner is processed based on the detected information, so that the waste toner can be reduced and a good image can be obtained. An image density of an image that is transferred with a predetermined reference electric field is detected in a first detecting step. An image density of an image that is transferred with an electric field that is smaller or greater than the reference electric field is detected in a second detecting step. A processing step of processing the degraded toner is performed on the basis of the image density detected by each of the detecting steps.Type: GrantFiled: November 21, 2008Date of Patent: April 24, 2012Assignee: Ricoh Company, Ltd.Inventor: Haruo Iimura
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Publication number: 20120045237Abstract: An image forming apparatus includes a transfer bias generator including a transfer bias supply that supplies a transfer bias to a transfer nip formed between an image carrier and a first rotary body, and a controller that detects a toner adhesion amount at a predetermined region of the image carrier located immediately upstream from the transfer nip and having a predetermined length in a moving direction of the image carrier. The transfer bias generator outputs at least an alternating current component under one of constant voltage control and constant current control and changes a target output value of the alternating current component according to the toner adhesion amount detected by the controller.Type: ApplicationFiled: August 11, 2011Publication date: February 23, 2012Inventors: Shinji AOKI, Haruo Iimura, Yasuhiko Ogino, Keigo Nakamura, Masahide Nakaya, Tomokazu Takeuchi
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Publication number: 20120045259Abstract: A transfer device includes an image carrier that carries a toner image; a nip forming member that forms a transfer nip between the nip forming member and the image carrier by contacting with a front surface of the image carrier; and a transfer bias applying unit that applies a transfer bias, thereby transferring the toner image carried on the image carrier to a recording material at a position of the transfer nip. The transfer bias applying unit applies the transfer bias in which an AC component and a DC component are superimposed and in which a peak-to-peak voltage of the AC component is larger than 6 times an absolute value of a voltage of the DC component.Type: ApplicationFiled: August 12, 2011Publication date: February 23, 2012Inventors: Keigo NAKAMURA, Haruo IIMURA, Shinji AOKI, Yasuhiko OGINO
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Patent number: 8045875Abstract: An image forming apparatus includes an image carrier for carrying a toner image and a transfer device. In the transfer device, a voltage applier applies a predetermined voltage to a transfer electric field generator. A potential measurement device measures a surface potential of the transfer electric field generator when a predetermined time period elapses after the voltage applier applies the predetermined voltage to the transfer electric field generator. A controller determines a transfer bias to be applied by at least one transfer member to the transfer electric field generator based on the measured surface potential of the transfer electric field generator. The at least one transfer member applies the transfer bias to the transfer electric field generator to generate a transfer electric field. The toner image is transferred from the image carrier onto a toner image receiver by the transfer electric field generated by the transfer electric field generator.Type: GrantFiled: November 10, 2008Date of Patent: October 25, 2011Assignee: Ricoh Company, LimitedInventors: Shinji Aoki, Haruo Iimura
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Patent number: 7662530Abstract: Provided is an image forming apparatus containing a latent electrostatic image bearing member, a latent electrostatic image forming unit configured to form a latent electrostatic image on the latent electrostatic image bearing member, a developing unit configured to develop the latent electrostatic image using a toner to form a toner image, and a transferring unit configured to transfer the toner image on a recording medium, wherein a surface of the toner is coated with an external additive containing fine particles having an average particle diameter Da of 100 nm to 300 nm, and a value obtained by dividing an average F of non-electrostatic adhesion between the toner and the latent electrostatic image bearing member by a product of volume average particle diameter of the toner Dt and average particle diameter of the external additive Da, [F/(Dt×Da)] is 7.5×104 N/m2 or less.Type: GrantFiled: June 22, 2006Date of Patent: February 16, 2010Assignee: Ricoh Company, Ltd.Inventor: Haruo Iimura
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Publication number: 20090142087Abstract: An image forming method includes detecting a toner degradation state by detecting an image density on an electrostatic latent image carrier with high sensitivity and low cost. The degraded toner is processed based on the detected information, so that the waste toner can be reduced and a good image can be obtained. An image density of an image that is transferred with a predetermined reference electric field is detected in a first detecting step. An image density of an image that is transferred with an electric field that is smaller or greater than the reference electric field is detected in a second detecting step. A processing step of processing the degraded toner is performed on the basis of the image density detected by each of the detecting steps.Type: ApplicationFiled: November 21, 2008Publication date: June 4, 2009Inventor: Haruo IIMURA
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Publication number: 20090123168Abstract: An image forming apparatus includes an image carrier for carrying a toner image and a transfer device. In the transfer device, a voltage applier applies a predetermined voltage to a transfer electric field generator. A potential measurement device measures a surface potential of the transfer electric field generator when a predetermined time period elapses after the voltage applier applies the predetermined voltage to the transfer electric field generator. A controller determines a transfer bias to be applied by at least one transfer member to the transfer electric field generator based on the measured surface potential of the transfer electric field generator. The at least one transfer member applies the transfer bias to the transfer electric field generator to generate a transfer electric field. The toner image is transferred from the image carrier onto a toner image receiver by the transfer electric field generated by the transfer electric field generator.Type: ApplicationFiled: November 10, 2008Publication date: May 14, 2009Inventors: Shinji Aoki, Haruo Iimura
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Publication number: 20060292470Abstract: Provided is an image forming apparatus containing a latent electrostatic image bearing member, a latent electrostatic image forming unit configured to form a latent electrostatic image on the latent electrostatic image bearing member, a developing unit configured to develop the latent electrostatic image using a toner to form a toner image, and a transferring unit configured to transfer the toner image on a recording medium, wherein a surface of the toner is coated with an external additive containing fine particles having an average particle diameter Da of 100 nm to 300 nm, and a value obtained by dividing an average F of non-electrostatic adhesion between the toner and the latent electrostatic image bearing member by a product of volume average particle diameter of the toner Dt and average particle diameter of the external additive Da, [F/(Dt×Da)] is 7.5×104 N/m2 or less.Type: ApplicationFiled: June 22, 2006Publication date: December 28, 2006Inventor: Haruo IIMURA
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Patent number: 6284424Abstract: A toner for developing an electrostatic latent image on a photoreceptor, wherein the toner includes particles, and wherein the particles of the toner having particle diameters within a range of D±d and measured in &mgr;m, wherein d≦2 &mgr;m, have an average non-electrostatic adhesion force Fne(D) and measured in nN against the photoreceptor, and wherein a proportional factor K of a primary regression line of a diagram in which the toner particle diameter D is plotted on the horizontal axis and the non-electrostatic adhesion force Fne(D) is plotted on the vertical axis, is from 0.01 nN/&mgr;m to 5 nN/&mgr;m.Type: GrantFiled: March 24, 2000Date of Patent: September 4, 2001Assignee: Ricoh Company, Ltd.Inventors: Haruo Iimura, Takeo Yamaguchi
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Patent number: 5595852Abstract: There are provided an organosilicon compound of formula (I) and a producing method thereof: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 each is an alkyl group having 1 to 6 carbon atoms, or a phenyl group which may have a substituent; R.sup.4 is an alkyl group which may have a substituent, an alicyclic alkyl group, a phenyl group which may have a substituent, or a benzyl group which may have a substituent; and X is a halogen atom, a benzenesulfonate radical, a hydroxynaphthalenesulfonate radical, BPh.sub.4, BF.sub.4, ClO.sub.4, or SbCl.sub.5. In addition, a toner and a two-component dry developer for developing latent electrostatic images containing the above organosilicon compound are also provided.Type: GrantFiled: September 27, 1995Date of Patent: January 21, 1997Assignee: Ricoh Company, Ltd.Inventors: Masakatsu Shimoda, Haruo Iimura, Hiroyuki Takahashi, Fuyuhiko Matsumoto
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Patent number: 5472635Abstract: Provided is a phase plate comprising a light transmitting base, an alignment layer formed on said base, and a film formed on said alignment layer by a liquid crystalline polymer which exhibits a nematic orientation in the state of liquid crystal and assumes a glassy state at a temperature below the liquid crystal transition point of the polymer.Type: GrantFiled: March 28, 1994Date of Patent: December 5, 1995Assignees: Nippon Oil Company, Ltd., Ricoh Company, Ltd.Inventors: Shigeki Iida, Takehiro Toyooka, Hiroyuki Itoh, Yasuyuki Takiguchi, Akihiko Kanemoto, Haruo Iimura
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Patent number: 5380459Abstract: The present invention discloses a liquid crystal display device with improved viewing angle dependency upon contrast and color, comprising a liquid crystal cell having a pair of substrates each equipped with transparent electrodes and a liquid crystal layer positioned therebetween, polarizers disposed on opposite sides of the cell and a compensation plate disposed between at least one of the polarizers and the cell, in which at least one layer of the compensation plate is an aligned film comprising a liquid crystalline polymer or a polymer having a specific molecular structure, and a refractive index in a direction perpendicular to a plane of the film is larger than the minimum refractive index in a direction parallel to the plane.Type: GrantFiled: April 19, 1991Date of Patent: January 10, 1995Assignee: Ricoh Company, Ltd.Inventors: Akihiko Kanemoto, Haruo Iimura, Yasuyuki Takiguchi
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Patent number: 5250214Abstract: The present invention discloses a liquid crystal color display device comprising;a liquid crystal cell comprising a pair of substrates, a liquid crystal layer positioned between the substrates and transparent electrodes on the substrates to apply voltage to the layer;a pair of polarizers positioned on opposite sides of the cell; anda combination of a color filter film and an optical phase plate positioned between the liquid crystal layer and at least one of the polarizers:wherein the phase plate comprises a film of liquid crystal polymer composition having polyester as a main constituent, being thermotropic and having a glass transition point, and the device is high in productivity, light in weight, good in color reproducibility, good in contrast, excellent in color tone display dependency upon viewing angle and wide in viewing angle.Type: GrantFiled: April 8, 1991Date of Patent: October 5, 1993Assignees: Ricoh Company, Ltd., Nippon Oil Company, LimitedInventors: Akihiko Kanemoto, Haruo Iimura, Yasuyuki Takiguchi, Shigeki Iida, Takehiro Toyooka, Hiroyuki Ito
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Patent number: 5243451Abstract: Disclosed herein is a DAP type-ECB system liquid crystal display device comprising (1) a liquid crystal cell in which a liquid crystal layer is sandwiched between a pair of substrates each having at least one electrode, (2) a birefringent layer sandwiched between a substrate and the liquid crystal cell and (3) a pair of polarizers disposed on outer surfaces of the substrates. The birefringent layer comprises a liquid crystal compound showing a cholesteric liquid crystal phase or a polymer film obtained by quenching a polymer showing a cholesteric phase to fix the aligning direction of the polymer molecules, and refractive indexes n.sub.x, n.sub.y within a plane of the birefringent layer and the refractive index n.sub.z in the direction perpendicular to the plane have a relationship:n.sub.x =n.sub.y >n.sub.z.Type: GrantFiled: January 5, 1993Date of Patent: September 7, 1993Assignee: Ricoh Company, Ltd.Inventors: Akihiko Kanemoto, Haruo Iimura, Yasuyuki Takiguchi
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Patent number: 5184237Abstract: A liquid crystal cell display device including a liquid crystal cell comprising a pair of substrates having transparent electrodes and aligning films, a liquid crystal composition with a positive dielectric anisotropy positioned between the substrates, major axes of the liquid crystal molecules being aligned nearly parallel in a plane parallel to the substrate when a field is applied and the liquid crystal molecules being twisted in an angle of 120.degree. to 360.degree.Type: GrantFiled: March 14, 1991Date of Patent: February 2, 1993Assignee: Ricoh Company, Ltd.Inventors: Haruo Iimura, Yasuyuki Takiguchi, Akihiko Kanemoto
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Patent number: 5175638Abstract: A liquid crystal display device including (1) a liquid crystal cell in which a liquid crystal layer with a liquid crystal composition having a positive dielectric anisotropy is sandwiched between a pair of substrates each having at least one electrode, and the liquid crystal molecules in the liquid crystal layer are homogeneously aligned between the substrates, (2) a pair of polarizers disposed so as to sandwich the liquid crystal cell therebetween and (3) at least one birefringent layer sandwiched between the liquid crystal layer and the polarizer, in which the maximum refractive index direction within the plane of the birefringent layer is substantially perpendicular to the aligning direction of the liquid crystal molecules. The device is excellent particularly in highly multiplexing driving characteristic as a black and white light shutter or a color display device.Type: GrantFiled: May 21, 1992Date of Patent: December 29, 1992Assignee: Ricoh Company, Ltd.Inventors: Akihiko Kanemoto, Yasuyuki Takiguchi, Haruo Iimura
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Patent number: 5150237Abstract: A liquid crystal display element has a liquid crystal cell contructed such that a liquid crystal layer composed of a liquid crystal composition having a positive dielectric anisotropy is homogeneously oriented between a pair of substrates provided with electrodes; a pair of polarizers disposed such that the liquid crystal layer is arranged between the polarizers; and a uniaxial medium disposed at least one of clearances between the liquid crystal layer and the both polarizers, the uniaxial medium having a positive optical anisotropy and an optical axis in a direction perpendicular to a substrate face. In the liquid crystal display element, products of refractive index anisotropy and thickness of the uniaxial medium are different from each other in accordance with the difference between displayed colors determined every display picture element.Type: GrantFiled: May 11, 1990Date of Patent: September 22, 1992Assignee: Ricoh Company, Ltd.Inventors: Haruo Iimura, Yasuyuki Takiguchi, Akihiko Kanemoto