Patents by Inventor Motoo Akagi
Motoo Akagi 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: 5252418Abstract: An electrophotographic photoreceptor comprising a photoconductive layer comprising a photoconductor, a support for the photoconductive layer and a surface layer formed on the photoconductive layer and comprising a curable resin film and an inorganic insulator pieces having a size larger than the film thickness of the curable resin film. In order to prevent the image blurring of an a-Si:H photoreceptor, on the outermost surface of the photoreceptor was formed a surface layer having a structure in which inorganic insulator pieces have protruded from the curable resin film. Since the curable resin is of high resistance and shows no quality change by corona irradiation, and besides the protruding inorganic insulator pieces prevent the abrasion of the resin, the surface layer having a long life and excellent humidity resistance, durability for corona irradiation and abrasion resistance can be realized.Type: GrantFiled: August 14, 1990Date of Patent: October 12, 1993Assignee: Hitachi, Ltd.Inventors: Fuminori Ishikawa, Akira Sato, Kunihiro Tamahashi, Masatoshi Wakagi, Katsumi Tamura, Masanobu Hanazono, Mitsuyoshi Shoji, Takayuki Nakakawaji, Yutaka Ito, Shigeki Komatsuzaki, Motoo Akagi, Masaaki Imamura
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Patent number: 5180616Abstract: A method for manufacturing a magnetic paint by mixing a resin composition powder as a dispersing binder for a magnetic powder with the magnetic powder, or together with a filler, and grinding the mixture under a high shear stress is disclosed. A magnetic recording medium such as a magnetic disk, etc., prepared by using the magnetic paint, can have a magnetic coating film having a substantially uniform film thickness of not more than 0.9 .mu.m and a surface roughness of not more than 0.05 .mu.m Ra before surface finishing.Type: GrantFiled: January 3, 1989Date of Patent: January 19, 1993Assignee: Hitachi, Ltd.Inventors: Hajime Fukke, Motoo Akagi, Iwao Matsuyama, Masayuki Katsumoto, Hitoshi Inoue, Naoki Kodama, Yasutaro Uesaka
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Patent number: 5149564Abstract: A method of forming a lubricating film which comprises to apply an emulsion composed of a fluorinated polymer, a surfactant and a dispersing medium to a substrate and then dry the film, and a method of preparing a magnetic recording medium which comprises to apply the above method to a magnetic recording medium, are disclosed.Type: GrantFiled: February 25, 1991Date of Patent: September 22, 1992Assignee: Hitachi, Ltd.Inventors: Atsushi Kato, Waichi Nagashiro, Motoo Akagi
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Patent number: 4794035Abstract: A magnetic recording medium which has a magnetic coating film that contains magnetic particles in a binder and which further has a lubricating layer formed on the magnetic coating film. The magnetic coating film has a surface that is processed with both a fluorinated surface treatment agent that bonds to the magnetic particles and a fluorinated surface treatment agent that bonds to the binder. The magnetic recording medium exhibits markedly improved sliding strength when the surface treatment agents and the lubricant have similar molecular structures. It is particularly preferred that the fundamental skeleton in the molecular structure of the surface treatment agents and the lubricant consists of a perfluoropolyether chain.Type: GrantFiled: September 4, 1987Date of Patent: December 27, 1988Assignee: Hitachi, Ltd.Inventors: Heigo Ishihara, Takanori Kudo, Tomoyuki Ohno, Motoo Akagi
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Patent number: 4789581Abstract: A sufficient reproduced output can be attained even in a coating thickness of as small as 1 .mu.m, preferably 0.1 to 0.5 .mu.m with a magnetic recording medium comprising a substrate and a coating film containing magnetic powder formed on the substrate, wherein the content of the magnetic powder in the coating film is 66 to 90% by weight.Type: GrantFiled: August 6, 1987Date of Patent: December 6, 1988Assignee: Hitachi, Ltd.Inventors: Hajime Fukke, Motoo Akagi, Yoshiki Kato, Waichi Nagashiro
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Patent number: 4722859Abstract: This invention relates to a magnetic recording medium comprising a magnetic recording film formed on a substrate directly or with a protective layer therebetween, characterized in that a surface treatment layer made of a reaction product of an azide compound is provided on the magnetic recording film, and preferably a lubricative material layer is further provided on the surface treatment layer. The surface treatment agent is covalently bonded to the surface of the magnetic recording film with an aid of nitrene to improve the durability of the magnetic recording film.Type: GrantFiled: September 8, 1986Date of Patent: February 2, 1988Assignee: Hitachi, Ltd.Inventors: Takanori Kudo, Heigo Ishihara, Motoo Akagi
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Patent number: 4520094Abstract: A photosensitive composition turning shicky by light exposure, which comprises a salt or p-aminobenzenediazonium compound and at least one of salts of o- and m-aminobenzenediazonium compounds, has a distinguished effect in forming a phosphor screen of a color picture tube.Type: GrantFiled: October 19, 1982Date of Patent: May 28, 1985Assignee: Hitachi, Ltd.Inventors: Hajime Morishita, Motoo Akagi, Nobuaki Hayashi, Saburo Nonogaki, Shoichi Uchino, Takahiro Kohashi
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Patent number: 4510226Abstract: A photosensitive composition becoming sticky upon exposure to light which comprises (a) a salt of a diazonium compound represented by the formula ##STR1## wherein R.sub.1 and R.sub.2 are independently --H, --CH.sub.3, --OCH.sub.3 or ##STR2## but R.sub.1 and R.sub.2 cannot be ##STR3## at the same time; and R.sub.3 and R.sub.4 are independently a straight-chain lower alkyl group, and (b) a salt of an aromatic diazonium compound having no --OH group directly bonding to a benzene ring, has an improved sensitivity because it contains the salt of the compound represented by the above formula. By using said photosensitive composition, there is provided a process for forming a pattern of powder coated layer excellent in light sensitivity.Type: GrantFiled: July 19, 1983Date of Patent: April 9, 1985Assignee: Hitachi, Ltd.Inventors: Hajime Morishita, Motoo Akagi, Saburo Nonogaki, Nobuaki Hayashi, Shoichi Uchino
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Patent number: 4409313Abstract: A photosensitive composition improved in sensitivity by adding a salt of a compound represented by the general formula: ##STR1## (wherein R.sub.1 and R.sub.2 each represents a straight chain alkyl group, and X, Y and Z each represents H, a straight chain alkyl group or an alkoxy group, but two or more of X, Y and Z can not be H at the same time) to an aromatic diazonium salt which gets sticky upon exposure to light.Type: GrantFiled: September 29, 1982Date of Patent: October 11, 1983Assignee: Hitachi, Ltd.Inventors: Hajime Morishita, Takahiro Kohashi, Saburo Nonogaki, Motoo Akagi, Nobuaki Hayashi, Shoichi Uchino
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Patent number: 4407916Abstract: A process for forming a fluorescent screen, where polychroic patterns are successively formed from at least two kinds of phosphors having different color emission or black powder by means of a photosensitive substance capable of turning tacky by light irradiation, which comprises bringing a finer particulate filling material than particles of the phosphors in contact with tackified parts when or after the particles of the phosphors are applied to the tackified parts in the individual steps of forming patterns each of the individual phosphors. The filling material saturates the tackiness of the phosphor pattern in question in advance to formation of a phosphor pattern in the successive step, and a cause for contamination of the pattern of the preceding step with the phosphor of the successive step can be eliminated thereby.Type: GrantFiled: March 15, 1982Date of Patent: October 4, 1983Assignee: Hitachi, Ltd.Inventors: Motoo Akagi, Shoichi Uchino, Saburo Nonogaki
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Patent number: 4377630Abstract: A photosensitive composition improved in sensitivity by adding a salt of a compound represented by the general formula: ##STR1## (wherein R.sub.1 and R.sub.2 each represents a straight chain alkyl group, and X, Y and Z each represents H, a straight chain alkyl group or an alkoxy group, but two or more of X, Y and Z can not be H at the same time) to an aromatic diazonium salt which gets sticky upon exposure to light.Type: GrantFiled: July 2, 1981Date of Patent: March 22, 1983Assignee: Hitachi, Ltd.Inventors: Hajime Morishita, Takahiro Kohashi, Saburo Nonogaki, Motoo Akagi, Nobuaki Hayashi, Shoichi Uchino
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Patent number: 4332874Abstract: Disclosed are a photosensitive composition comprising a copolymer comprising acrylamide, diacetone-acrylamide and a sulfonated vinyl monomer, such as sodium p-styrenesulfonate, and a water-soluble aromatic bisazide compound, and a pattern-forming method using this photosensitive composition.This photosensitive composition has a reciprocity law failure, and when this photosensitive composition is used, the development after light exposure is completed in a short time.Type: GrantFiled: October 24, 1980Date of Patent: June 1, 1982Assignee: Hitachi, Ltd.Inventors: Nobuaki Hayashi, Motoo Akagi, Kiyoshi Miura, Yoshiyuki Odaka
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Patent number: 4101440Abstract: A chemically digestive agent for releasing photoresist films comprising hydrogen peroxide and sulfamic acid is particularly suitable for the production of the fluorescent screen of a black matrix color television image receiving tube in that it has a strong releasing action for various photoresist films and low corrosiveness for machinery and appliances. The addition of a fixed amount of iron ion can further improve the characteristics of the chemically digestive agent.Type: GrantFiled: July 15, 1976Date of Patent: July 18, 1978Assignee: Hitachi, Ltd.Inventors: Motoo Akagi, Hazime Morishita, Saburo Nonogaki, Makoto Tanaka, Tadao Kaneko
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Patent number: 4086090Abstract: The present invention affords a process for forming a pattern having a surface area substantially equal to or smaller than area of apertures of shadow-mask through which beams pass on a photoresist film, which contains an acrylamidediacetoneacrylamide copolymer and a water-soluble aromatic bisazide compound, by exposing said photoresist film to light through a mask having the pattern and then developing the film.The use of said photoresist film for the preparation of a phosphor screen of a color picture tube of a black matrix or black stripe type does not require a special technique such as post-etching of a shadow mask and makes it possible to form a three primary color phosphor pattern having a surface area substantially equal to or smaller than the area of apertures of the shadow mask through which lightbeams pass, without mutual "bridging" between phosphor dots. Thus, an excellent phosphor screen of a color picture tube of a black matrix or black stripe type can be prepared.Type: GrantFiled: September 22, 1975Date of Patent: April 25, 1978Assignee: Hitachi, Ltd.Inventors: Takahiro Kohashi, Motoo Akagi, Yoichi Oba, Saburo Nonogaki, Makoto Tanaka, Tadao Kaneko, Yoshifumi Tomita