Patents by Inventor Masao Kawamura
Masao Kawamura 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: 5191224Abstract: To achieve higher packaging density and one wafer level for a full-sized wafer memory, or wafer-scale integration memory system, the wafers are vertically stacked with each other at a predetermined interval. A packaging technique is improved in such a way that a memory system layout can be precisely realized and a precise through hole can be formed. Moreover, other chips are fixed on the wafer so as to achieve furthermore the high packaging density.Type: GrantFiled: December 13, 1990Date of Patent: March 2, 1993Assignee: Hitachi, Ltd.Inventors: Masanori Tazunoki, Hiromitsu Mishimagi, Makoto Homma, Toshiyuki Sakuta, Hisashi Nakamura, Keiji Sasaki, Minoru Enomoto, Toshihiko Satoh, Kunizo Sahara, Shigeo Kuroda, Kanji Otsuka, Masao Kawamura, Hinoko Kurosawa, Kazuya Ito
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Patent number: 5175372Abstract: In a process of producing high purity bis(4-hydroxyphenyl)sulfides which comprises reacting phenols with sulfur dichloride in an organic solvent, the improvement comprising: reacting the phenols with sulfur dichloride in a nonpolar organic solvent; removing partly or wholly the nonpolar organic solvent after the reaction; adding a polar organic solvent to the reaction mixture to dissolve the reaction mixture therein at elevated temperatures; and crystallizing out the high purity bis(4-hydroxyphenyl)sulfides.There is further provided a high performance heat-sensitive recording material which comprises high purity bis(4-hydroxy-3-methylphenyl)sulfide thus prepared and having a melting point in the range of from 123.9.degree. C. to 124.9.degree. C. as a developer and a fluoran compound as a color former.Type: GrantFiled: April 10, 1991Date of Patent: December 29, 1992Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Akira Onoe, Masao Kawamura, Kunioki Kato, Tomiharu Amitani, Makoto Sato, Tsuyoshi Morishita
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Patent number: 5141888Abstract: A bipolar type of semiconductor integrated circuit device is provided with U-shaped grooves which are formed by cutting a main surface of a semiconductor body to form isolation regions between bipolar transistors. A silicon oxide film can be formed in the U-shaped grooves by thermal oxidation simultaneously with the formation of a silicon oxide film used to form isolation regions between each collector contact region and base region. No separate step is needed for forming the silicon oxide film between the collector contact region and the base region. The thickness of the silicon oxide film can be controlled, and has a sufficient thickness even at its two edges, i.e., at its boundaries with the U-shaped grooves, so that the bipolar transistors exhibit good electrical characteristics. Namely, the collector resistance thereof does not increase, and the breakdown voltage at the pn junction between the collector region and the base region does not decrease.Type: GrantFiled: January 18, 1991Date of Patent: August 25, 1992Assignee: Hitachi, Ltd.Inventors: Mikinori Kawaji, Toshihiko Takakura, Akihisa Uchida, Shigeo Kuroda, Yoichi Tamaki, Takeo Shiba, Kazuhiko Sagara, Masao Kawamura
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Patent number: 5119084Abstract: In a liquid crystal driving apparatus for driving a liquid crystal display panel in accordance with an image signal, the response speed of a liquid crystal display panel is increased so as not to produce an afterimage upon motion image display. A signal is preprocessed by an inverse transfer function of the transfer function of the liquid crystal panel, i.e., signal processing for emphasizing an image change in a timer direction is performed, and the liquid crystal display panel is driven by using the processed data.Type: GrantFiled: November 22, 1989Date of Patent: June 2, 1992Assignee: Casio Computer Co., Ltd.Inventors: Masao Kawamura, Takahiro Fuse
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Patent number: 5117224Abstract: In driving a color liquid crystal panel having red, green and blue color filters, a color liquid crystal display apparatus sets signal electrodes of these three colors in a no-bias status during a non-display period of an image signal in such a manner as to permit at least two colors of the signal electrodes have mutually different effective voltages. The effective voltages in the no-bias state are set at values which provide the optimum value for .DELTA.n.multidot.d (.DELTA.n: birefringence) in accordance with cell gaps d on the signal electrodes, thereby minimizing the height difference between the color filters.Type: GrantFiled: February 13, 1989Date of Patent: May 26, 1992Assignee: Casio Computer, Ltd.Inventors: Masao Kawamura, Ken Yoshino
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Patent number: 5102858Abstract: In a process of producing high purity bis(4-hydroxyphenyl) sulfides which comprises reacting phenols with sulfur dichloride in organic solvents, the improvement comprising: reacting the phenols with sulfur dichloride in nonpolar organic solvents; removing partly or wholly the nonpolar organic solvents after the reaction; adding polar organic solvents to the reaction mixture to dissolve the reaction mixture therein at elevated temperatures; and crystallizing out the high purity bis(4-hydroxyphenyl)sulfides.There is further provided a high performance heat-sensitive recording material which comprises high purity bis(4-hydroxy-3-methylphenyl)sulfide thus prepared and having a melting point in the range of from 123.9.degree. C. to 124.9.degree. C. as a developer and a fluoran compound as a color former.Type: GrantFiled: June 12, 1989Date of Patent: April 7, 1992Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Akira Onoe, Masao Kawamura, Kunioki Kato, Tomiharu Amitani, Makoto Sato, Tsuyoshi Morishita
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Patent number: 5101049Abstract: Novel compounds, 2-(.alpha.-alkoxyimino)ethylthiophenes are susceptible to electrophilic substitution reactions, and the acetylation, nitration, sulfonation and halogenation of the compounds provide 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-nitro-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenesulfonic acid and 5-halo-2-(.alpha.-alkoxyimino)ethylthiophenes, respectively.The hydrolysis of 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes readily provides a known compound, 2,5-diacetylthiophene which is an important intermediate for the production of medicines, whereas the haloform reaction provides novel compounds, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenecarboxylic acids, the hydrolysis of which compounds readily provides a known compound, 5-acetyl-2-thiophenecarboxylic acids, an important intermediate for the production of medicines.The hydrolysis of 5-(.alpha.Type: GrantFiled: August 20, 1990Date of Patent: March 31, 1992Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Hiroshi Goda, Masao Kawamura, Kunioki Kato, Makoto Sato
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Patent number: 5084402Abstract: A semiconductor device employing a new isolation process is disclosed, wherein an isolation area is a region in which a burying material is buried in a deep groove formed in a semiconductor body with a substantially constant width by anisotropic dry etching, semiconductor elements are formed in selected ones of semiconductor regions isolated by the isolation area, and others of the semiconductor regions, with no semiconductor element formed therein, have their whole surface covered with a thick oxide film which is produced by the local oxidation of the semiconductor body.The new isolation process is well-suited for a bipolar type semiconductor device, wherein the deep groove is formed so as to reach a semiconductor substrate through an N.sup.+ -type buried layer, and a thick oxide film formed simultaneously with the aforementioned thick oxide film isolates the base region and collector contact region of a bipolar transistor.Type: GrantFiled: May 17, 1989Date of Patent: January 28, 1992Assignee: Hitachi, Ind.Inventors: Akihisa Uchida, Daisuke Okaka, Toshihiko Takakura, Katsumi Ogiue, Yoichi Tamaki, Masao Kawamura
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Patent number: 5019523Abstract: Disclosed is a process for making a bipolar transistor which comprises an n-type Si semiconductor body having a convex portion, an insulation film covering the surface of the semiconductor body other than the convex portion, and a p-type polycrystalline Si layer formed on the insulation film. A p-type region formed in the convex portion serves as an intrinsic base region, the polycrystalline Si layer serves as an extrinic base region, an n-type region formed in the intrinsic base region serves as an emitter region, and the body serves as a collector region.Type: GrantFiled: March 30, 1990Date of Patent: May 28, 1991Assignee: Hitachi, Ltd.Inventors: Tohru Nakamura, Takao Miyazaki, Susumu Takahashi, Ichiro Imaizumi, Takahiro Okabe, Minoru Nagata, Masao Kawamura
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Patent number: 5011788Abstract: A bipolar type of semiconductor integrated circuit device is provided with U-shaped grooves which are formed by cutting a main surface of a semiconductor body to form isolation regions between bipolar transistors. A silicon oxide film can be formed in the U-shaped grooves by thermal oxidation simultaneously with the formation of a silicon oxide film used to form isolation regions between each collector contact region and base region. No separate step is needed for forming the silicon oxide film between the collector contact region and the base region. The thickness of the silicon oxide film can be controlled, and has a sufficient thickness even at its two edges, i.e., at its boundaries with the U-shaped grooves, so that the bipolar transistors exhibit good electrical characteristics. Namely, the collector resistance thereof does not increase, and the breakdown voltage at the pn junction between the collector region and the base region does not decrease.Type: GrantFiled: December 15, 1988Date of Patent: April 30, 1991Assignee: Hitachi, Ltd.Inventors: Mikinori Kawaji, Toshihiko Takakura, Akihisa Uchida, Shigeo Kuroda, Yoichi Tamaki, Takeo Shiba, Kazuhiko Sagara, Masao Kawamura
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Patent number: 4965566Abstract: In a signal electrode drive circuit of an image display apparatus, the latch pulses are sequentially shifted for a plurality of latch circuits so as to sequentially latch the digital image data, and the signal electrode of the dot-matrix type display panel is driven by the signal having a plurality of gradation, based upon the digital image data latched in the latch circuits. The image input data are alternately read out via the buffer circuits by two-phase clock pulses, the input data are transferred to the latch circuits in response to the two-phase clock pulses, and, as a consequence, image data of higher transfer frequency can be satisfactorily processed.Type: GrantFiled: November 25, 1988Date of Patent: October 23, 1990Assignee: Casio Computer Co., Ltd.Inventors: Masao Kawamura, Minoru Usui
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Patent number: 4943655Abstract: Process for preparing 2-alkyl-5-haloacetylbenzenesulfonamide represented by the general formula (1), ##STR1## (wherein R.sup.1 is an alkyl group having 1 to 5 carbon atoms; and X is a chlorine atom, bromine atom or iodine atom), characterized by halogenating a 5-acetyl-2-alkylbenzenesulfonamide represented by the general formula (2), ##STR2## (wherein R.sup.1 is the same as defined above) in a lower alcohol represented by the general formula (3),R.sup.4 --OH(wherein R.sup.4 is an alkyl group having 1 to 5 carbon atoms).Type: GrantFiled: March 24, 1989Date of Patent: July 24, 1990Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Kunioki Kato, Masao Kawamura, Hiroshi Goda, Kiyoshi Sawada, Kazuhiro Hamatani
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Patent number: 4933737Abstract: A bipolar transistor comprises an n-type Si semiconductor body having a convex portion, an insulation film covering the surface of the semiconductor body other than the convex portion, and a p-type polycrystalline Si layer formed on the insulation film. A p-type region formed in the convex portion serves as an intrinsic base region, the polycrystalline Si layer serves as an extrinsic base region, an n-type region formed in the intrinsic base region serves as an emitter region, and the body serves as a collector region.Type: GrantFiled: June 1, 1987Date of Patent: June 12, 1990Assignee: Hitachi, Ltd.Inventors: Tohru Nakamura, Takao Miyazaki, Susumu Takahashi, Ichiro Imaizumi, Takahiro Okabe, Minoru Nagata, Masao Kawamura
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Patent number: 4859998Abstract: A signal electrode drive circuit for driving a liquid crystal display panel includes a latch circuit for latching a digitized video signal, a buffer, a graduation signal-forming circuit, an intensity modulation pulse-generating circuit, and an analog multiplexer. The latch circuit holds the video data only once during one horizontal scanning period until a next latch pulse M is generated, thus considerably reducing current dissipation.Type: GrantFiled: June 14, 1988Date of Patent: August 22, 1989Inventors: Masao Kawamura, Minoru Usui
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Patent number: 4853158Abstract: Process for preparing 2-alkyl-5-haloacetylbenzenesulfonamide represented by the general formula (1), ##STR1## (wherein R.sup.1 is an alkyl group having 1 to 5 carbon atoms; and X is a chlorine atom, bromine atom or iodine atom), characterized by halogenating a 5-acetyl-2-alkylbenzenesulfonamide represented by the general formula (2), ##STR2## (wherein R.sup.1 is the same as defined above) in a lower alcohol represented by the general formula (3),R.sup.4 --OH(wherein R.sup.4 is an alkyl group having 1 to 5 carbon atoms).Type: GrantFiled: March 25, 1988Date of Patent: August 1, 1989Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Kunioki Kato, Masao Kawamura, Hiroshi Goda, Kiyoshi Sawada, Kazuhiro Hamatani
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Patent number: 4853343Abstract: A semiconductor device employing a new isolation process is disclosed, wherein an isolation area is a region in which a burying material is buried in a deep groove formed in a semiconductor body with a substantially constant width by anisotropic dry etching, semiconductor elements are formed in selected ones of semiconductor regions isolated by the isolation area, and others of the semiconductor regions, with no semiconductor element formed therein, have their whole surface covered with a thick oxide film which is produced by the local oxidation of the semiconductor body.The new isolation process is well-suited for a bipolar type semiconductor device, wherein the deep groove is formed so as to reach a semiconductor substrate through an N.sup.+ -type buried layer, and a thick oxide film formed simultaneously with the aforementioned thick oxide film isolates the base region and collector contact region of a bipolar transistor.Type: GrantFiled: March 18, 1988Date of Patent: August 1, 1989Assignee: Hitachi, Ltd.Inventors: Akihisa Uchida, Daisuke Okada, Toshihiko Takakura, Katsumi Ogiue, Yoichi Tamaki, Masao Kawamura
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Patent number: 4849138Abstract: A method of producing alkali metal benzenesulfinates having the general formula of ##STR1## wherein M represents Na or K, which comprises: reacting nitrophenylphenyl sulfones having the general formula of ##STR2## wherein n is an integer of 1 or 2, with alkali metal thiophenolates having the general formula of ##STR3## in solvents. The reaction produces also nitrophenylphenyl sulfides as by-products in equimolar amounts to the alkali metal benzenesulfinates, and the oxidation of the sulfides provides the starting nitrophenylphenyl sulfones.A method of producing the nitrophenylphenyl sulfones is also provided wherein the sulfides are oxidized with hydrogen peroxide in the presence both of water-soluble tungstates or molybdates and of phase transfer catalysts in a two-phase heterogeneous solvent.Type: GrantFiled: August 12, 1987Date of Patent: July 18, 1989Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Akira Onoe, Masao Kawamura, Kunioki Kato, Masato Yoshikawa, Hirokazu Kagano
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Patent number: 4835317Abstract: Novel compounds, 4-tert.-butyl-1,2-benzenedithiol and bis(4-tert.-butyl-1,2-dithiophenolate) metal complexes having the general formula of ##STR1## wherein M represents a trivalent transition metal, and A represents a quarternary ammonium are provided.The novel benzenedithiol is produced by reacting 4-tert.-butylbenzenethiol or di(4-tert.-butylphenyl)disulfide with sulfur monochloride in the presence of iodine or a Lewis acid in a solvent, and then reducing the resultant product with a metal selected from the group consisting of zinc, tin, iron and aluminum in the presence of an acid.The novel Cu, Co and Ni complexes are produced by reacting the benzenedithiol with a salt of the corresponding divalent transition metal in the presence of an alkoxide metal or a hydride metal and a quarternary ammonium salt in a solvent under an oxidative atmosphere.Type: GrantFiled: January 13, 1988Date of Patent: May 30, 1989Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Michio Suzuki, Masao Kawamura, Kunioki Kato, Masahide Takahashi, Tsuyoshi Morishita, Kazuyuki Nakayama, Akio Nakatsuka
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Patent number: 4819054Abstract: A bipolar type of semiconductor integrated circuit device is provided with U-shaped grooves which are formed by cutting a main surface of a semiconductor body to form isolation regions between bipolar transistors. A silicon oxide film can be formed in the U-shaped grooves by thermal oxidation simultaneously with the formation of a silicon oxide film used to form isolation regions between each collector contact region and base region. No separate step is needed for forming the silicon oxide film between the collector contact region and the base region. The thickness of the silicon oxide film can be controlled, and has a sufficient thickness even at its two edges, i.e., at its boundaries with the U-shaped grooves, so that the bipolar transistors exhibit good electrical characteristics. Namely, the collector resistance thereof does not increase, and the breakdown voltage at the pn junction between the collector region and the base region does not decrease.Type: GrantFiled: February 6, 1987Date of Patent: April 4, 1989Assignee: Hitachi, Ltd.Inventors: Mikinori Kawaji, Toshihiko Takakura, Akihisa Uchida, Shigeo Kuroda, Yoichi Tamaki, Takeo Shiba, Kazuhiko Sagara, Masao Kawamura
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Patent number: 4792612Abstract: Novel compounds, 2-(.alpha.-alkoxyimino)ethylthiophenes are susceptible to electrophilic substitution reactions, and the acetylation, nitration, sulfonation and halogenation of the compounds provide 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-nitro-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenesulfonic acid and 5-halo-2-(.alpha.-alkoxyimino)ethylthiophenes, respectively.The hydrolysis of 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes readily provides a known compound, 2,5-diacetylthiophene which is an important intermediate for the production of medicines, whereas the haloform reaction provides novel compounds, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenecarboxylic acids, the hydrolysis of which compounds readily provides a known compound, 5-acetyl-2-thiophenecarboxylic acids, an important intermediate for the production of medicines.The hydrolysis of 5-(.alpha.Type: GrantFiled: March 21, 1988Date of Patent: December 20, 1988Assignee: Seitetsu Kagaku Co., Ltd.Inventors: Hiroshi Goda, Masao Kawamura, Kunioki Kato, Makoto Sato