Synthetic Resin Patents (Class 252/62.54)
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Patent number: 6638367Abstract: The objects of the present invention are to provide a method of producing highly weather-resistant iron-based magnet powder containing a rare-earth element, particularly characterized by high coercive force in a practically important humid atmosphere, highly weather-resistant magnet powder produced by the same method, resin composition containing the same powder for bonded magnets, and bonded magnet containing the same powder. The present invention provides a method of producing a magnet powder by crushing an iron-based magnet powder containing a rare-earth element in an organic solvent, wherein phosphoric acid is added to the solvent in which the powder is crushed.Type: GrantFiled: September 19, 2001Date of Patent: October 28, 2003Assignee: Sumitomo Metal Mining Co., Ltd.Inventors: Kenji Ohmori, Toshiyuki Osako, Kayo Hashiguchi, Kouichi Yokosawa
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Publication number: 20030183800Abstract: Fine spinel-type ferrimagnetic particles of the present invention have a composition represented by the formula (I):Type: ApplicationFiled: January 29, 2003Publication date: October 2, 2003Inventors: Hiroshi Yamamoto, Yukihiro Nissato
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Patent number: 6627101Abstract: A magnetic polymer composite comprising 60-90% by weight of the polymer, 10-40% by weight of magneto-resistive alloys and 5-30% by weight of the additive prepared by the process by dissolving 60-90% by weight of the polymer in a solvent to obtain a clear, colorless solution; adding 10-40% by weight of alloy and 5-30% by weight of the additive in the said clear color less solution; agitating the said clear, color less solution at a frequency of 15-20 kHz for a period of 5-30 minutes, to get equally dispersed alloy in the said polymer solution; transferring the said polymer solution with equally dispersed said magneto-resistive alloys and additive to the open non-metallic container on a magneto-stirrer allowing the said solvent to evaporate till the polymer coated transition metal based alloys are isolated in the form of cones from the said non-metallic container.Type: GrantFiled: April 9, 2001Date of Patent: September 30, 2003Assignee: Indian Institute of TechnologyInventors: Solomon Sundar Manoharan, Manju Lata Rao
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Patent number: 6627102Abstract: Disclosed herein is a magnetic powder which can provide magnets having excellent magnetic properties and having excellent reliability especially excellent heat stability. The magnetic powder is composed of an alloy composition represented by (R1-aDya)x(Fe1-bCob)100-x-yBy (where R is at least one kind of rare-earth element, x is 7.1-9.9 at %, y is 4.6-8.0 at %, a is 0.02-0.2, and b is 0-0.30), wherein the magnetic powder is constituted from a composite structure having a soft magnetic phase and a hard magnetic phase, and the intrinsic coercive force (HCJ) of the magnetic powder at a room temperature is in the range of 400-750 kA/m.Type: GrantFiled: May 22, 2001Date of Patent: September 30, 2003Assignee: Seiko Epson CorporationInventors: Akira Arai, Hiroshi Kato
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Patent number: 6620337Abstract: In a method of manufacturing a composite magnetizer, flat soft magnetic powder that strain is removed and magnetic coating of slurry regime consisting of a binder dissolved in a solvent are formed in a sheet by die-coating, gravure coating, or reverse coating. The binder includes a vinyl chloride resin with glass-transition temperature of not lower than 50° C.Type: GrantFiled: October 24, 2000Date of Patent: September 16, 2003Assignee: Tokin CorporationInventors: Norihiko Ono, Shigeyoshi Yoshida
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Patent number: 6610404Abstract: A magnetorheological fluid (32) having controlled-shaped particles (56,68), such as rod, prism, tetrahedral, and other regularly shaped particles. The regularly shaped particles (56, 68) increase the field yield and responsive to particle interaction forces. The magnetorheological material has particular use for space applications such as vibration isolators, vibration dampeners, and latch mechanisms.Type: GrantFiled: February 13, 2001Date of Patent: August 26, 2003Assignee: TRW Inc.Inventors: John A. Starkovich, Emil M. Shtarkman
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Publication number: 20030154865Abstract: A molecular sieve apparatus and magnetic/adsorbent material composition that facilitate molecular absorption and separation using a magnetic field to hold, move, cool, and/or heat a magnetoadsorbent composed of an adsorbent (1) that is bonded to a magnetic material (3) by a binder (2). The ability to move the magnetoadsorbent using a magnetic field increases the efficiency of the absorption cycle, because the magnetoadsorbent can be moved to a location in the cycle having the most optimized conditions.Type: ApplicationFiled: October 16, 2002Publication date: August 21, 2003Inventor: David A. Zornes
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Publication number: 20030155548Abstract: An object of the present invention is to provide a hydraulic-composition bonded magnet having moldability, heat resistance, corrosion resistance and high strength.Type: ApplicationFiled: March 4, 2003Publication date: August 21, 2003Inventors: Satoshi Ozawa, Eishi Fukuda, Shuuji Matsumura
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Patent number: 6599375Abstract: A composite magnetic body 1, comprising a soft magnetic powder (2) and a binding agent (3), in which the specific surface area of the soft magnetic powder (2) is 0.1-3 m2/g. The surface state of the soft magnetic powder contained in the composite magnetic body is defined in terms of specific surface area, and self-extinguishing properties, i.e. fire resistance properties, are obtained. An electromagnetic interference suppressing body is obtained using this composite magnetic body.Type: GrantFiled: June 13, 2001Date of Patent: July 29, 2003Assignee: NEC Tokin CorporationInventor: Yoshio Awakura
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Patent number: 6599608Abstract: Substantially spherical magneto-plumbite ferrite (barium or strontium ferrite) particles are formed from well-dispersed ultra-fine substantially spherical iron-based oxide and/or hydroxide particles as precursor particles. The precursor particles are mixed with a colloidal barium or strontium carbonate (BaCO3 or SrCO3), and with small amounts of a byproduct, such as sodium or potassium chloride (NaCl or KCl) or hydroxide (NaOH or KOH) or nitrate (NaNO3 or KNO3), functioning as a flux to lower the calcination temperature. The particles are filtered out of the mixture, dried, and calcined for a time sufficiently long and/or at a temperature sufficiently high to form magneto-plumbite ferrite from the precursor particles, and for a time sufficiently short and/or a temperature sufficiently low to maintain the general spherical shape of the precursor particles.Type: GrantFiled: July 8, 2002Date of Patent: July 29, 2003Assignee: Idaho Research Foundation, Inc.Inventors: Yang-Ki Hong, Hong Sik Jung, Patrick R. Taylor
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Publication number: 20030136056Abstract: A magnetic-abrasive powder has a magnetic component, an abrasive component, an adhesive component which connects particles of the magnetic component with particles of the abrasive component, the adhesive component being a light curing adhesive component which contains catalysts and is polymerizable under the action of ultraviolet and visible light.Type: ApplicationFiled: January 24, 2002Publication date: July 24, 2003Inventors: Gennady Kremen, Leonid Igelshteyn, Savva Feygin
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Patent number: 6596096Abstract: Permanent magnets, devices including permanent magnets and methods for manufacture are described with the permanent magnet comprising, for example: iron-boron-rare earth alloy particulate having an intrinsic coercive force of at least about 1591 kiloamperes/meter (about 20 kiloOersteds) and a residual magnetization of at least about 0.8 tesla (about 8 kiloGauss), wherein the rare earth content comprises praseodymium, a light rare earth element selected from the group consisting of cerium, lanthanum, yttrium and mixtures thereof, and balance neodymium; and a binder bonding the particulate.Type: GrantFiled: August 14, 2001Date of Patent: July 22, 2003Assignee: General Electric CompanyInventors: Ralph James Carl, Gerald Burt Kliman, Juliana Chiang Shei, Mark Gilbert Benz, Judson Sloan Marte
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Patent number: 6596200Abstract: Provided is an electronic material composition which is capable of forming a cured film exhibiting a desired glass transition temperature, a desired stiffness modulus in a rubbery state and a desired extensibility at low temperatures. Also provided is an electronic component comprising a molded body, a packed body, a covering body, an electrode or a joining body, all being formed of the aforementioned electronic material composition. Also provided is a method of using the aforementioned electronic material composition, which is featured in that the electronic material composition is applied in a semi-cured state, and after the application thereof, completely cured.Type: GrantFiled: June 30, 2000Date of Patent: July 22, 2003Assignee: Taiyo Yuden Co., Ltd.Inventors: Hideki Ogawa, Kinya Iri, Mitsuyoshi Ito
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Patent number: 6590385Abstract: A sensor assembly includes a spool that has magnetic filaments incorporated therein. The magnetic filaments are magnetized to create a magnetic flux around the spool. A coil is wound around the spool such that it is within the magnetic flux field generated by the spool. A target wheel having plural teeth and plural slots is placed so that its outer periphery is slightly spaced from the target wheel. As the target wheel rotates, it induces changes in the magnetic flux density sensed by the coil. The changes in flux density can be used to determine the angular position and angular speed of the target wheel and a moving part attached thereto. Since the spool is magnetized, the need for a separate magnet is obviated.Type: GrantFiled: July 6, 2001Date of Patent: July 8, 2003Assignee: Delphi Technologies, Inc.Inventor: Benjamin Valles
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Publication number: 20030098436Abstract: The present invention includes coating composition having magnetic properties for application to a substrate. The coating composition includes a plurality of strontium and or barium hexaferrite particles having a random magnetic pole alignment. The coating composition also includes a binder adhesive capable of suspending the strontium hexaferrite particles. The binder adhesive is a natural rubber capable of adhering in a substantially thin film to the substrate. The strontium hexaferrite particles are normally present between 50% to 98% of the coating composition's total weight when dried on the substrate. The thickness of the film of the coating composition ranges from 0.5 mils to 20 mils, and has 6 to 24 magnetic pole changes per linear inch. The binder adhesive allows for manipulation of the strontium hexaferrite particles to a non-random magnetic pole alignment after the ferromagnetic particles have dried in the binder adhesive on the substrate.Type: ApplicationFiled: October 5, 2001Publication date: May 29, 2003Inventors: R. William Graham, Daniel F. Peters, Charles E. Adams, Ricky L. Helton
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Patent number: 6565673Abstract: Carbon addition to the rapidly solidified, preferably melt spun, alloy system of Sm(Co, Fe, Cu, Zr) provides for good isotropic magnetic properties. Importantly, these alloys are nanocomposite in nature and comprise the SmCoC2 phase. Thermal processing of these materials can achieve good magnetic properties at lower temperatures and/or shorter processing times than conventional Sm(Co, Fe, Cu, Zr) powders for bonded magnet application.Type: GrantFiled: June 15, 2001Date of Patent: May 20, 2003Assignee: Santoku CorporationInventors: Wei Gong, Bao-Min Ma
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Publication number: 20030089881Abstract: A magnetically responsive foam has a three-dimensional cellular structure comprising the reaction product of a liquid phase foam system to which has been added a magnetic fluid and a blowing agent.Type: ApplicationFiled: October 11, 2001Publication date: May 15, 2003Inventor: Edward M. Purizhansky
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Publication number: 20030089882Abstract: A composition for resin-bonded magnets. The resin-bonded magnets using the composition of the resin have excellent service lives in industry, excellent magnetic characteristics and excellent mechanical strength. A composition for resin-bonded magnets contains a magnetic powder and resin binder. The magnetic powder contains a transition metal element as one of the constituent elements. The binder contains, as the major ingredient, a thermosetting resin containing an organic peroxide and having radical-polymerization reactivity, and is further incorporated with an N-oxyl compound. Also disclosed is a composition including magnetic powder, thermosetting resin having radical-polymerization reactivity and organic oxide as the major ingredients, and a resin-bonded magnet using the same.Type: ApplicationFiled: July 12, 2002Publication date: May 15, 2003Inventors: Shoichi Yoshizawa, Ryuji Kodama, Shin-ichi Hayashi
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Patent number: 6558482Abstract: Disclosed herein is a magnetic powder which can provide a magnet having a high magnetic flux density and excellent magnetizability and reliability especially excellent heat resisting property (heat stability). The magnetic powder is composed of an alloy composition represented by Rx(Fe1−yCoy)100-x-z-wBzAlw (where R is at least one kind of rare-earth element, x is 8.1-9.4 at %, y is 0-0.30, z is 4.6-6.8 at %, and w is 0.02-1.Type: GrantFiled: July 20, 2000Date of Patent: May 6, 2003Assignee: Seiko Epson CorporationInventors: Akira Arai, Hiroshi Kato
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Patent number: 6558565Abstract: A composite magnetic body used for a choke coil, etc. is formed by compression molding of a mixture of magnetic alloy powder containing iron (Fe) and nickel (Ni) as the main component, an insulating material and a binder of an acrylic resin. In the composite magnetic body, high packing rate of the magnetic alloy powder and good insulation between the powder particles stand together, exhibiting a low core loss and a high magnetic permeability. The composite magnetic body can be formed in various core pieces of complex shapes.Type: GrantFiled: November 20, 2000Date of Patent: May 6, 2003Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Nobuya Matsutani, Yuji Mido, Hiroshi Fujii
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Patent number: 6555018Abstract: The invention relates to magnets, particularly bonded magnets, of the Re—Fe—B type made from atomized magnetic powders and to methods of producing the powders and the magnet. The magnetic powders comprise, by weight, about 15% to 25% of RE; about 0.8% to 2.0% of B; about 1% to 10% of T; and balanced with Fe, Co, or mixtures thereof; wherein RE is one or more rare earth elements selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Er, Gd, Tb, Dy, Ho, Tm, Yb and Lu, and T is one or more elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. To produce bonded magnets, the atomized powders are heat treated, combined with a binder, pressed or molded, and cured to produce the bonded magnets.Type: GrantFiled: February 28, 2001Date of Patent: April 29, 2003Assignee: Magnequench, Inc.Inventors: Charles Howard Sellers, Barry Hal Rabin, Wilhelm Ervens, Joseph James Worden, Viswanathan Panchanathan
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Publication number: 20030070729Abstract: Permanent magnets, devices including permanent magnets and methods for manufacture are described with the permanent magnet comprising, for example: iron-boron-rare earth alloy particulate having an intrinsic coercive force of at least about 1591 kiloamperes/meter (about 20 kiloOersteds) and a residual magnetization of at least bout 0.8 tesla (about 8 kiloGauss), wherein the rare earth content comprises praseodymium, a light rare earth element selected from the group consisting of cerium, lanthanum, yttrium and mixtures thereof, and balance neodymium; and a binder bonding the particulate.Type: ApplicationFiled: August 14, 2001Publication date: April 17, 2003Applicant: General Electric CompanyInventors: Ralph James Carl, Gerald Burt Kliman, Juliana Chiang Shei, Mark Gilbert Benz, Judson Sloan Marte
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Publication number: 20030066983Abstract: Magnetorheological materials are provided comprising magnetic particles, a polymeric gel and a carrier material. The polymerization of the gel is preferentially accomplished in the presence of the magnetic particles and the carrier material. Magnetorheological materials are provided having a selected off-state viscosity and a selected on-state apparent viscosity. The method of preparing these magnetorheological materials is also provided. The carrier material, the polymeric gel and the magnetic particles are selected so that the resulting magnetorheological material has the desired off-state viscosity and on-state apparent viscosity. These materials have good dispersion characteristics, reduced settling, superior off-state viscosity and superior apparent viscosity in the presence of a magnetic field.Type: ApplicationFiled: February 20, 2001Publication date: April 10, 2003Inventors: Alan Fuchs , Faramarz Gordaninejad , Daniel Blattman , Gustav Hamann
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Patent number: 6537463Abstract: A resin-bonded magnet composed substantially of (a) an R—T—N-based magnetic powder having a basic composition of R&agr;T100−&agr;−&bgr;N&bgr;, wherein R is at least one selected form the group consisting of rare earth elements including Y, T is Fe or Fe and Co, 5≦&agr;≦20, and 5≦&bgr;≦30, (b) a ferrite magnetic powder having a substantially magnetoplumbite-type crystal structure and a basic composition represented by (A1−xR′x) O[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R′ is at least one selected from the group consisting of rare earth elements including Y, La being indispensable, M is Co or Co and Zn, 0.01≦x<0.4, 0.005≦y≦0.04, and 5.0≦n≦6.4, and (c) a binder. The ferrite magnet powder is preferably an anisotropic, granulated powder or an anisotropic, sintered ferrite magnet powder.Type: GrantFiled: December 11, 2000Date of Patent: March 25, 2003Assignee: Hitachi Metals, Ltd.Inventors: Katsunori Iwasaki, Masahiro Tobise, Yasunobu Ogata, Mikio Shindo, Hiroshi Okajima
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Publication number: 20030047706Abstract: A mixed powder useful as a starting material for dust core comprises a uniform mixture of a soft magnetic powder and a binder resin so that the resultant dust core has an electric resistance capable of suppressing an eddy current between the soft magnetic powdery particles and high mechanical strength at room temperatures and also at high temperatures. In the mixed powder, the binder resin is made of a phenolic resin powder which has a methylol groups in the molecule and preferably has an average particle size of 30 &mgr;m or below and wherein when the phenolic resin powder is dissolved in boiling methanol in large excess, a content of an undissolved matter is at least 4 wt % based on the total of the phenolic resin. A dust core obtained from the mixed powder and its fabrication method are also described.Type: ApplicationFiled: March 19, 2002Publication date: March 13, 2003Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd)Inventors: Hiroyuki Mitani, Tsukasa Yuri, Kazuhisa Fujisawa, Yoshikazu Seki, Masahiro Murakami, Hirofumi Houjou
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Publication number: 20030044547Abstract: The present invention discloses an ultraviolet light curable ferromagnetic composition and method for making such a composition that may be used to produce a ferromagnetic coating on a suitable substrate. These coatings may be used to produce printed capacitors and inductors. The disclosed composition does not contain any significant amount of volatile organic solvents that do not become incorporated in the active layer after curing.Type: ApplicationFiled: July 11, 2002Publication date: March 6, 2003Inventor: Roy C. Krohn
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Patent number: 6527972Abstract: Magnetorheological materials are provided comprising magnetic particles, a polymeric gel and a carrier material. The polymerization of the gel is preferentially accomplished in the presence of the magnetic particles and the carrier material. Magnetorheological materials are provided having a selected off-state viscosity and a selected on-state apparent viscosity. The method of preparing these magnetorheological materials is also provided. The carrier material, the polymeric gel and the magnetic particles are selected so that the resulting magnetorheological material has the desired off-state viscosity and on-state apparent viscosity. These materials have good dispersion characteristics, reduced settling, superior off-state viscosity and superior apparent viscosity in the presence of a magnetic field.Type: GrantFiled: February 20, 2001Date of Patent: March 4, 2003Assignee: The Board of Regents of the University and Community College System of NevadaInventors: Alan Fuchs, Faramarz Gordaninejad, Daniel Blattman, Gustav H. Hamann
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Patent number: 6527971Abstract: In a rare-earth bonded magnet of the invention, magnetic powder containing a rare-earth element is bonded together by a binding resin. The rare-earth bonded magnet may further contain an antioxidant and a lubricant. The binding resin contains a high molecular compound comprising the following structure unit; —X—R—X—Y—Ar—Y— (where X is a functional group containing a nitrogen atom, Y is a functional group containing a carbonyl group, R is a normal-chain or branched alkylene group having a carbon number of 6-16, and Ar is an aromatic ring residue).Type: GrantFiled: February 1, 2001Date of Patent: March 4, 2003Assignee: Seiko Epson CorporationInventors: Yoshiki Nakamura, Koji Akioka
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Publication number: 20030034476Abstract: A polyamide plastic magnetic material excellent in fluidity is provided, and a plastic magnet made of the same is highly flexible with no deterioration in strength and does not crack during fabrication. The polyamide plastic magnetic material consists of: magnetic powder; polyamide resin; and a predetermined amount of bis unsaturated fatty acid amide represented by the formula: R1—CONH—R3—NHCO—R2 where R1 and R2 is an unsaturated hydrocarbon group having at least one double bond and R3 is a hydrocarbon group. The three components are kneaded into a final magnetic material.Type: ApplicationFiled: July 10, 2002Publication date: February 20, 2003Applicant: Minebea Co., Ltd.Inventors: Takahiro Sasazawa, Yoshimichi Sakama
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Patent number: 6521140Abstract: In a composite magnetic body comprising flat soft magnetic powder dispersed in an organic binding agent, biodegradable plastic is used as the organic binding agent so that the composite magnetic body is free of possibility of pollution due to disposal thereof. As the biodegradable plastic, any of a microbe-generated type, a chemically-synthesized type and a natural high molecular weight type is used.Type: GrantFiled: March 27, 2001Date of Patent: February 18, 2003Assignee: NEC Tokin Corp.Inventors: Shigeyoshi Yoshida, Norihiko Ono
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Publication number: 20030030155Abstract: A resin component for encapsulating a semiconductor includes magnetic powder and silica powder whose average particle diameter is smaller than the average particle diameter of the magnetic powder. Thus, the curing body of the resin component for encapsulating a semiconductor has an electromagnetic wave shielding function by the magnetic powder. Since the spaces of the magnetic powder are filled with the silica powder whose average particle diameter is small, the moldability of the curing body is improved and the insulating characteristics thereof are enhanced. Such a resin component for encapsulating a semiconductor is employed, there can be produced a preferably formed and encapsulated semiconductor device having the electromagnetic wave shielding function and having no malfunction generated due to leakage current from a semiconductor element.Type: ApplicationFiled: June 7, 2002Publication date: February 13, 2003Inventors: Junichi Toyoda, Katsumi Okayama, Kazumasa Igarashi
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Publication number: 20030030027Abstract: The present invention includes magnetizable coating composition for application to a substrate. The coating composition includes a plurality of strontium and or barium hexaferrite particles having a random magnetic pole alignment. The coating composition also includes a binder adhesive capable of suspending the strontium hexaferrite particles. The binder adhesive is a latex capable of adhering in a substantially thin film to the substrate. The strontium hexaferrite particles are normally present between 50% to 98% of the coating composition's total weight when dried on the substrate. The thickness of the film of the coating composition is at least about 0.5 mils thick, and has 6 to 24 magnetic pole changes per linear inch. The binder adhesive allows for manipulation of the strontium hexaferrite particles to a non-random magnetic pole alignment after the ferromagnetic particles have dried in the binder adhesive on the substrate.Type: ApplicationFiled: July 31, 2001Publication date: February 13, 2003Inventors: R. William Graham, Daniel F. Peters, Charles E. Adams, Ricky L. Helton
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Publication number: 20030010408Abstract: A magnetic powder 4 is produced by use of a plating mold M which is pattern-formed with an electrode range 10 corresponding to the shape of a magnetic powder 4 and an insulative range surrounding the periphery of the electrode range, precipitating films 40 of the magnetic material selectively in the electrode range through an electroplating and then peeling the films 40 from the plating mold. The flat magnetic powders 4 where are regular in plane shapes and diameters among or between powders or where average crystal grain diameters are 100 nm or smaller, are much dispersed into an insulative resin as a bonding agent.Type: ApplicationFiled: February 13, 2002Publication date: January 16, 2003Inventors: Akihisa Hosoe, Koji Nitta, Shinji Inazawa, Katsumi Okayama, Junichi Toyoda
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Patent number: 6503415Abstract: Disclosed herein is a magnet powder which can provide a magnet having a high magnetic flux density and excellent magnetizability and reliability. The magnet powder is composed of an alloy composition represented by Rx(Fe1−yCOy)100−x−z−wBzAlw (where R is at least one kind of rare-earth element, x is 8.1-9.4 at %, y is 0-0.30, z is 4.6-6.8 at %, and w is 0.02-0.8 at %), and it has a structure in which a soft magnetic phase and a hard magnetic phase exist adjacent with each other. The magnet powder has characteristics in which, when an isotropic bonded magnet is molded by mixing the magnet powder with a binding resin, the magnetic flux density (B) of the bonded magnet, in the region of B higher than the straight line for Pc (permeance coefficient)=2.Type: GrantFiled: December 23, 1999Date of Patent: January 7, 2003Assignee: Seiko Epson CorporationInventor: Akira Arai
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Publication number: 20020197461Abstract: A method for manufacturing single crystal ceramic powder is provided. The method includes a powder supply step for supplying powder consisting essentially of ceramic ingredients to a heat treatment area with a carrier gas, a heat treatment step for heating the powder supplied to the heat treatment area at temperatures required for single-crystallization of the powder to form a product, and a cooling step for cooling the product obtained in the heat treatment step to form single crystal ceramic powder. The method provides single crystal ceramic powder consisting of particles with a very small particle size and a sphericity being 0.9 or higher.Type: ApplicationFiled: May 29, 2002Publication date: December 26, 2002Inventors: Minoru Takaya, Yoshiaki Akachi, Hiroyuki Uematsu, Hisashi Kobuke
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Publication number: 20020193236Abstract: A method for manufacturing spherical ceramic powder is provided. The method includes essentially a spray drying step and a sintering step. In the spray drying step, a spray nozzle is used to spray slurry containing powdered raw material consisting essentially of ceramic ingredients to form liquid droplets, and liquid contents in the liquid droplets are heated and removed to obtain ceramic granular powder. In the sintering step, the ceramic granular powder is sintered to form spherical ceramic powder. The method provides ceramic powder having a mean particle size of about 1-50 &mgr;m and a sphericity of about 0.8 or higher, which is suited for mixing with resin material to form a compound. The ceramic powder has high dispersant and filling properties against the resin material.Type: ApplicationFiled: May 29, 2002Publication date: December 19, 2002Inventors: Minoru Takaya, Yoshiaki Akachi, Tomohiro Sogabe, Hisashi Kobuke
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Publication number: 20020190236Abstract: A composition for producing granules for molding ferrite, which comprises a ferrite slurry at least having raw ferrite powders; an ethylene-modified polyvinyl alcohol whose ethylene modified amount is from 4 to 10 mol %, average polymerization degree is from 500 to 1700, and average saponification degree is from 90.0 to 99.5 mol %; and water mixed therewith, ferrite granules produced from the composition, ferrite green body produced from the granules and ferrite sintered body produced from the sintered body are disclosed.Type: ApplicationFiled: April 26, 2002Publication date: December 19, 2002Applicant: TDK CORPORATIONInventor: Hiroshi Harada
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Patent number: 6494968Abstract: Lamellar rare earth-iron-boron-based magnet alloy particles for a bonded magnet, having an intrinsic coercive force (iHc) of not less than 3.5 kOe, a residual magnetic flux density (Br) of not less than 9.5 kG, and a maximum energy product ((BH)max) of not less than 13 MGOe. These particles have an average major axial diameter of 60 to 500 &mgr;m, an average minor axial diameter of 50 to 460 &mgr;m, an average axis ratio (major axial diameter/minor axial diameter) of 1.1 to 10 and an average aspect ratio (major axial diameter/thickness) of 3 to 100. The magnet alloy particles have a residual magnetic flux density (Br) as high as not less than 10 kG, an intrinsic coercive force (iHc) as large as not less than 3.5 kOe and a maximum energy product ((BH)max) as large as not less than 13 MGOe, are used as a material for high-performance bonded magnets.Type: GrantFiled: February 2, 1999Date of Patent: December 17, 2002Assignee: Toda Kogyo CorporationInventors: Masaaki Hamano, Minoru Yamasaki, Hirotaka Mizuguchi
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Patent number: 6478891Abstract: The ribbon shaped magnet material (quenched ribbon 8) according to the present invention is obtained by ejecting a molten liquid 6 of an alloy containing rare earth elements and transition metals from a nozzle 3, and quenching the molten liquid allowing it to collide with a circumference face 53 of a cooling roll 5. The micostructure of the quenched ribbon comprises. soft magnetic phases and hard magnetic phases in adjoining relation to one another. Crystal grain sizes of the quenched ribbon 8 preferably satisfy the following equations [1] and [2], and preferably satisfy at least one of the following equations [3] and [4]: D1s/D1h≦0.9 [1] D2s/D2h≦0.8 [2] 0.5≦D1h/D2h≦1 [3] 0.Type: GrantFiled: July 24, 2001Date of Patent: November 12, 2002Assignee: Seiko Epson CorporationInventors: Akira Arai, Hiroshi Kato
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Patent number: 6478889Abstract: The method for producing iron-base alloy permanent magnet powder of the present invention includes the steps of: chilling an Fe—R—B molten alloy by melt quenching, thereby forming a rapidly solidified alloy having a thickness in a range of 80 &mgr;m to 300 &mgr;m; crystallizing the rapidly solidified alloy by heat treatment, thereby producing an alloy having permanent magnet properties; and pulverizing the alloy to produce powder having an average particle size in a range of 50 &mgr;m to 300 &mgr;m or less and a ratio of minor axis size to major axis size of powder particles in a range of 0.3 to 1.0.Type: GrantFiled: December 13, 2000Date of Patent: November 12, 2002Assignee: Sumitomo Special Metals Co., Ltd.Inventor: Hirokazu Kanekiyo
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Publication number: 20020162987Abstract: In a composition for a plastic magnet, containing an Nd—Fe—B based alloy powder and a ferrite magnetic material powder mixed to a resin material, the Nd—Fe—B based alloy powder has particle sizes distributed in a range of 100 to 400 &mgr;m, and the ferrite magnetic material powder has an average particle size of approximately 1 &mgr;m. The weight ratio of the Nd—Fe—B based alloy powder to the ferrite magnetic material powder is in a range of 30:70 to 70:30. Further, the ratio of the total weight of the Nd—Fe—B based alloy powder 2 and the ferrite magnetic material powder 3 to the weight of the resin material is in a range of 90:10 to 80:20. Thus, in a plastic magnet 1 formed using the composition, peripheries of particles of the Nd—Fe—B based alloy powder 2 are surrounded by particles of the ferrite magnetic material powder 3 and the resin material.Type: ApplicationFiled: April 9, 2002Publication date: November 7, 2002Inventor: Satoshi Kazamaturi
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Patent number: 6476110Abstract: Rubber compositions filled with an unusually high content of solid magnetizable particles such as iron oxide or strontium ferrite but having great resistance to crack initiation and crack growth. This allows generation of strongly magnetized areas in rubber articles built with a rubber composition according this invention. This gives—also in those applications where a large distance between a row of magnetized areas and a sensor is necessary due to deformation—well-reproducible and well-recognizable signals despite existence of disturbing magnetic fields. The magnetizable particles are bonded to a rubber matrix by a bonding agent, namely an organo-functional silane.Type: GrantFiled: February 18, 2000Date of Patent: November 5, 2002Assignee: Continental AGInventors: Frank Paul Papp, Duane Marle Oxley, James Michael Giustino
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Patent number: 6475404Abstract: Magnetorheological fluid concentrates are provided which contain a substantially dry mixture of magnetic-responsive powder and a thixotropic agent. The concentrates may be mixed with an aqueous or an organic carrier fluid to form magnetorheological fluids.Type: GrantFiled: May 3, 2000Date of Patent: November 5, 2002Assignee: Lord CorporationInventor: J. David Carlson
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Patent number: 6468678Abstract: Magnetic, conformable articles for use with traffic bearing surfaces are disclosed which comprise an organic binder having magnetic particles distributed therein. The articles may be employed in intelligent vehicle guidance systems, and in systems to guide other mobile objects such as farm animals, pets, or visually impaired pedestrians. Methods of making the articles and methods of using the systems to control and/or guide a mobile object using the magnetic field generated from the articles are also described.Type: GrantFiled: October 22, 1997Date of Patent: October 22, 2002Assignee: 3M Innovative Properties CompanyInventors: Thomas J. Dahlin, Gregory F. Jacobs, David M. Hopstock, Robert L. Keech, Richard E. Fayling, Richard G. Newell, Claud M. Lacey, Bernard A. Gonzalez
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Patent number: 6468440Abstract: Magnet powder has a composition expressed by (R1XR2YBZT100−X−Y−Z)100−QNQ (in formula, R1 is at least one kind of element selected from rare earth elements, R2 is at least one kind of element selected from Zr, Hf and Sc, T is at least one kind of element selected from Fe and Co, and X, Y, Z and Q are numbers satisfying 2 atomic %≦X, 0.01 atomic %≦Y, 4≦X+Y≧20 atomic %, 0≦Z≦10 atomic %, and 0.1≦Q≦20 atomic %, respectively), and TbCu7 crystal phase as a principal phase. In such magnet powder, a ratio of fine particles of which maximum diameter is 22 &mgr;m or less is 20% by weight or less. Alternatively, surface roughness of particles constituting the magnet powder is 5 &mgr;m or less in terms of maximum height Ry provided in JIS B 0601-1994. Accordingly, to such a magnet powder, excellent magnetic properties can be obtained with reproducibility.Type: GrantFiled: September 22, 2000Date of Patent: October 22, 2002Assignee: Kabushiki Kaisha ToshibaInventors: Shinya Sakurada, Tomohisa Arai, Masami Okamura, Keisuke Hashimoto, Takahiro Hirai
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Patent number: 6451221Abstract: An extrudable magnet composition includes composite particles including thermoplastic resin and magnetic material, and a surface additive selected from silicon dioxide particles and ferrite particles, wherein the surface additive is applied to a surface of the composite particles.Type: GrantFiled: December 28, 2000Date of Patent: September 17, 2002Assignee: Xerox CorporationInventors: Steven C. Hart, Lois A. Eckstrom
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Patent number: 6451220Abstract: A magnetic composition comprised of cobalt ferrite nanoparticles dispersed in an ionic exchange resin.Type: GrantFiled: January 21, 1997Date of Patent: September 17, 2002Assignee: Xerox CorporationInventors: Ronald F. Ziolo, Javier Tejada Palacios, Elizabeth C. Kroll, Xixiang Zhang, Rachel Pieczynski
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Patent number: 6416681Abstract: Granule for forming ferrite is provided by mixing powders of ferrite raw material, polyvinyl alcohol as a binder and polyethylene glycol added as plasticizer and having molecular weight being 1000 to 6000, and forming granules.Type: GrantFiled: August 23, 2000Date of Patent: July 9, 2002Assignee: TDK CorporationInventor: Hiroshi Harada
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Patent number: 6416830Abstract: A tube for externally covering or bundling electric cables is provided for suppressing radiation of undesired electromagnetic waves. The tube is made of a material in which soft magnetic powder is mixed with and dispersed into an organic binding agent. For protecting the cable from the undesired electromagnetic waves from the exterior, it is preferable to provide a conductor layer at an outer side of a composite magnetic layer. For facilitating mounting onto the cable, the tube is provided with a slit in a longitudinal direction. Alternatively, the cable may have a spiral structure. As an organic binding agent, it is preferable to use an elastomer which is excellent in extensible property. Further, it is preferable that the soft magnetic powder is powder being essentially flat.Type: GrantFiled: April 24, 1998Date of Patent: July 9, 2002Assignee: Tokin CorporationInventors: Shigeyoshi Yoshida, Mitsuharu Sato
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Publication number: 20020084440Abstract: The objects of the present invention are to provide a highly weather-resistant iron-based magnet powder containing a rare-earth element, characterized by high coercive force in a practically important humid atmosphere, resin composition containing the same powder for bonded magnets, and bonded and compacted magnets containing the same powder. The present invention provides the above-described products by optimizing the functions and types of the phosphate coating film, uniformly formed over the surfaces of the iron-based magnet powder particles containing a rare-earth element.Type: ApplicationFiled: September 27, 2001Publication date: July 4, 2002Applicant: SUMITOMO METAL MINING CO., LTD.Inventors: Kenji Ohmori, Toshiyuki Osako, Kayo Hashiguchi, Kouichi Yokosawa