Magnetizable Powder, Flakes, Or Particles Utilized Patents (Class 427/550)
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Publication number: 20090200791Abstract: The present invention discloses a security element comprising a transparent substrate and a magnetically oriented image coating on said substrate, wherein said image coating is preferably laid out such as to show a 3-dimensional effect, appearing in positive or negative relief respectively, if observed form the recto- or the verso side, respectively. The security element can be easily identified by the unaided eye, by just turning around the document and observing the angle-dependent image on either side. On the other hand, the security element cannot be reproduced by scanning or copying the document.Type: ApplicationFiled: July 6, 2007Publication date: August 13, 2009Applicant: SICPA HOLDING S.A.Inventors: Claude-Alain Despland, Mathieu Schmid, Pierre Degott, Edgar Müller, Albert Stichelberger
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Publication number: 20090197123Abstract: A storage device includes a storage medium, a controller and a read/write head. The storage medium includes a substrate with a plurality of nano-structures arranged in an ordered pattern on a surface of the substrate. The controller is coupled to the storage medium. The controller has a read structure that extends over the substrate and a positioner adapted to adjust a position of the read structure relative to the substrate. The read/write head is mounted on the read structure and positioned over the substrate during operation. The read/write head is adapted to read and to write information to and from the plurality of nano-structures.Type: ApplicationFiled: December 23, 2008Publication date: August 6, 2009Applicant: Seagate Technology LLCInventors: Joachim W. Ahner, Nisha Shukla, Dieter Weller
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Patent number: 7482041Abstract: A device having a substrate, a pair of ferromagnetic leads on a surface of the substrate, laterally separated by a gap, and one or more ferromagnetic microparticles comprising a conductive coating at least partially within the gap. The conductive coating forms at least part of an electrical connection between the leads. A molecular junction may connect the leads to the microparticle.Type: GrantFiled: December 12, 2007Date of Patent: January 27, 2009Assignee: The United States of America as represented by the Secretary of the NavyInventors: David P Long, James G Kushmerick, Jr.
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Publication number: 20090010823Abstract: The present invention provides new microreactor systems, catalysts, and chemical processes. Methods of making novel catalysts and reaction apparatus are also described.Type: ApplicationFiled: January 15, 2008Publication date: January 8, 2009Applicant: Velocys Corp.Inventors: Terry J. Mazanec, Yong Wang, Laura J. Silva, David P. Vanderwiel
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Patent number: 7449212Abstract: A security document with a security element, wherein the security element includes at least partly a material that is optically changeable by an electric or magnetic field. In addition, a corresponding method for producing such a security document and a test method for testing such a security document are described.Type: GrantFiled: April 16, 2003Date of Patent: November 11, 2008Assignee: Giesecke & Devrient GmbHInventor: Walter Schneider
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Publication number: 20070237891Abstract: A pattern is formed by applying a coating composition containing magnetic particles to an article so that a coating film is formed, and a plurality of sheet form magnets are placed along the front surface of this coating film. Adjacent sheet form magnets are arranged in such a state that the magnetic poles on the front surface and the magnetic poles on the back surface are different between adjacent sheet form magnets, and side surfaces of the sheet form magnets contact each other. The coating composition contains a thermoplastic resin, magnetic particles with flaky form and a specific low boiling point solvent and a specific high boiling point solvent. A magnetic field is applied to the coating film by the sheet form magnets, so that the magnetic particles in the coating film are oriented by the magnetic field and the magnetic particles are oriented substantially parallel to the front surface of the coating film above the contact portions between the sheet form magnets.Type: ApplicationFiled: April 5, 2007Publication date: October 11, 2007Applicants: INOAC CORPORATION, SANG BROLI COMPANY LIMITEDInventors: Yoshinori Sugiura, Jun Nishikawa, Ryoichi Nakaoka, Chika Kanada, Akito Harada
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Patent number: 7258900Abstract: A magnetic field is applied to planarize magnetic pigment flakes relative to a surface. Pigment flakes, such as optically variable pigment flakes, are used in a variety of paints, inks, extrusions, powder coatings, and other forms for decorative and security applications. In many applications pigment flakes tend to align parallel to each other and to the surface to which they are applied. If the pigment flakes include a suitable magnetic structure, a magnetic field can be applied to subsequently align the flakes or enhance the alignment of the flakes in the plane of the substrate if the carrier that the flakes are dispersed in is still fluid. In some printing operations, pigment flakes that are applied parallel to the substrate are pulled out of plane when the print screen or printing die is lifted off the substrate. Application of a magnetic field can re-align pigment flakes to the plane of the substrate, enhancing the visual quality of the printed image, especially with optically variable pigments.Type: GrantFiled: November 13, 2002Date of Patent: August 21, 2007Assignee: JDS Uniphase CorporationInventors: Vladimir P. Raksha, Charles T. Markantes, Dishuan Chu, Paul G. Coombs
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Patent number: 7172795Abstract: A method for making three-dimensional structures of nanometric or micrometric dimensions comprises the following steps: obtaining of a photopolymeric or UV mixture including nanoparticles orientable in space; deposition of a layer of the mixture on a respective substrate; exposure of the layer to UV-radiation and control of the polymerization of the mixture by means of variation of its index of refraction; application of a magnetic and/or electrical field for producing a desired positioning of the nanoparticles, in order to induce the growth of surface projections from the layer of mixture; and polymerization of the mixture.Type: GrantFiled: September 8, 2003Date of Patent: February 6, 2007Assignee: C.R.F. Societa Consortile per AzioniInventors: Vito Lambertini, Piermario Repetto, Piero Perlo
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Patent number: 7128798Abstract: A process of making a magnetic assembly having at least one magnetic layer and at least one printable substrate layer including the steps of providing a magnetic composition comprising about 70 wt-% to about 95 wt-% of at least one magnetic material and about 5 wt-% to about 30 wt-% of at least one thermoplastic binder, forming the magnetic composition into a magnetic layer, and directly applying the magnetic composition at an elevated temperature in molten form to a printable substrate layer, and to the magnetic composition and any articles made therefrom.Type: GrantFiled: November 21, 2001Date of Patent: October 31, 2006Assignee: MagaetNotes, Ltd.Inventors: Randall A. Boudouris, Raymond S. Richards
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Patent number: 7097885Abstract: A method of manufacturing electric machines comprised of geometrically patterned arrays of permanent magnets, soft magnetic materials, and electrical conductors deposited by kinetic spraying methods directly atop a carrier. The magnets and planar coils of the present invention may be integrally formed atop carriers to form electrical machines such as motors, generators, alternators, solenoids, and actuators. The manufacturing techniques used in this invention may produce highly defined articles that do not require additional shaping or attaching steps. Very high-purity permanent and soft magnetic materials, and conductors with low oxidation are produced.Type: GrantFiled: June 17, 2003Date of Patent: August 29, 2006Assignee: Ford Global Technologies, LLCInventors: Franco Leonardi, John Matthew Ginder, Robert Corbly McCune
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Patent number: 7071006Abstract: Carriers hold remote-acting bodies which can be manipulated by a remote force, and also hold a micro-substance which is a target substance of an assay. The remote-acting bodies are manipulated in order to control the positions of the micro-substances, so as to execute assays for various target substances efficiently, at low cost, easily, and reliably. Various aspects of interest include the carriers which hold the micro-substances, a system suspending the carriers, an apparatus for manipulating the carriers, and a method of controlling the position of the carriers.Type: GrantFiled: December 27, 2001Date of Patent: July 4, 2006Assignee: Precision System Science Co., Ltd.Inventors: Hideji Tajima, Yoshiro Okami
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Patent number: 6881450Abstract: The invention is directed to a method of magnetically linking a ferromagnetic object to a partially magnetized coating material made by applying a coating to a surface of a continuously-moving medium including the steps of providing a coating material by mixing a binder material suitable for being spread substantially and regularly over the surface and a ferromagnetic component, the binder material being a hot melt adhesive; providing a continuously-moving medium having a top surface to be substantially coated, the surface capable of receiving a substantially and regularly spread coating material; passing the coating material and continuously-moving medium between rollers to form a substantially constant thickness of the coating material substantially covering the top surface and allowing the coating material to set to form the coated medium as a magnetizable component, wherein the medium that is coated is one of a paper, a card, wallpaper, a flexible plastic sheet, a rigid plastic sheet, and walls; partiallyType: GrantFiled: July 7, 1999Date of Patent: April 19, 2005Inventor: Claude Texier
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Patent number: 6878305Abstract: Coupling components to an underlying substrate using a composition of a polymer and magnetic material particles. Upon applying the composition between the component and the printed circuit board, the composition may be subjected to a magnetic field to align the magnetic material particles into a conductive path between the component and the underlying substrate. At the same time the polymer-based material may be cured or otherwise solidified to affix the conductive path formed by the magnetic material particles.Type: GrantFiled: October 28, 2003Date of Patent: April 12, 2005Assignee: Intel CorporationInventors: George Hsieh, Terrance J. Dishongh, Norman J. Armendariz, David V. Spaulding
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Patent number: 6835450Abstract: Multilayer magnetic recording medium is suitable for high recording densities and the recording of digital data, has very good electromagnetic recording properties in the entire recording wavelength range and good mechanical properties and possesses a flat frequency response and which has at least one upper magnetic recording layer less than 0.5 &mgr;m thick and at least one lower layer which contains a magnetically soft pigment.Type: GrantFiled: April 6, 2001Date of Patent: December 28, 2004Assignee: Imation Corp.Inventors: Ronald John Veitch, Albert Kohl, Helmut Jakusch, Andreas Ilmer, Peter Heilmann, Ria Kress, Stefan Müller, Johannes Sandrock
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Patent number: 6821573Abstract: A flexible laminate, comprising: the light-active second layer acts without external energizing to change the properties of incident light such that the light reflected by this layer has signaling properties; a first layer serving as carrier layer; a light-active second layer situated on an outer surface of this laminate; and a permanent magnetic third layer for releasable magnetic attachment of the laminate to a ferromagnetic surface. The laminate has the feature that the light-active second layer acts without external energizing to change the properties of incident light such that the light reflected by this layer has signaling properties.Type: GrantFiled: January 24, 2001Date of Patent: November 23, 2004Assignee: Budev B.V.Inventor: Max G. Paping
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Patent number: 6818155Abstract: Coupling components to an underlying substrate using a composition of a polymer and magnetic material particles. Upon applying the composition between the component and the printed circuit board, the composition may be subjected to a magnetic field to align the magnetic material particles into a conductive path between the component and the underlying substrate. At the same time the polymer-based material may be cured or otherwise solidified to affix the conductive path formed by the magnetic material particles.Type: GrantFiled: January 2, 2002Date of Patent: November 16, 2004Assignee: Intel CorporationInventors: George Hsieh, Terrance J. Dishongh, Norman J. Armendariz, David V. Spaulding
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Patent number: 6773765Abstract: Disclosed is a process for making a flexible magnet with an induced anisotropy, and in particular to a process for making a flexible anisotropic magnet by thermal spraying in the presence of an applied magnetic field. The method may be used to fabricate a substrate having a flexible anisotropic magnetic coating or a free standing anisotropic flexible magnet.Type: GrantFiled: November 4, 1999Date of Patent: August 10, 2004Assignee: The Research Foundation of State University of New YorkInventors: Richard J. Gambino, Dongil Shin, Jeffrey A. Brogan
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Patent number: 6773763Abstract: A method of manufacturing a permanent magnet by the steps of preparing an admixture of magnetic material and binder material, the admixture material having a particle size of less than 325 mesh. Then heating a carrier gas to a temperature substantially below the melting point of either component of the admixture. The admixture is introduced into the carrier gas and the admixture is sprayed atop a ductile carrier. The admixture adheres to the carrier and forms a solid permanent magnet. An electric field is applied to the sprayed admixture to create a permanent magnetic moment.Type: GrantFiled: July 29, 2002Date of Patent: August 10, 2004Assignee: Ford Global Technologies, LLCInventors: Franco Leonardi, John Matthew Ginder, Robert Corbly McCune
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Patent number: 6759097Abstract: Methods and devices for producing images on coated articles are provided. The methods generally comprise applying a layer of magnetizable pigment coating in liquid form on a substrate, with the magnetizable pigment coating containing a plurality of magnetic non-spherical particles or flakes. A magnetic field is then applied to selected regions of the pigment coating while the coating is in liquid form, with the magnetic field altering the orientation of selected magnetic particles or flakes. Finally, the pigment coating is solidified, affixing the reoriented particles or flakes in a non-parallel position to the surface of the pigment coating to produce an image such as a three dimensional-like image on the surface of the coating. The pigment coating can contain various interference or non-interference magnetic particles or flakes, such as magnetic color shifting pigments.Type: GrantFiled: December 23, 2002Date of Patent: July 6, 2004Assignee: Flex Products, Inc.Inventors: Roger W. Phillips, Charlotte R. LeGallee, Charles T. Markantes, Paul G. Coombs, Matthew R. Witzman
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Publication number: 20040091634Abstract: A passivated magneto-resistive bit structure is disclosed in which surfaces subjects to oxidation or corrosion are protected. In one embodiment, a bit structure is encapsulated by means of an etch stop barrier material. In another embodiment an etch stop barrier material protects the top of a bit structure and dielectric spacers protect the side walls.Type: ApplicationFiled: August 22, 2003Publication date: May 13, 2004Applicant: Micron Technology, Inc.Inventors: Harry Liu, Lonny Berg, William L. Larson, Shaoping Li, Theodore Zhu, Joel Drewes
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Patent number: 6733613Abstract: An anisotropic conductive compound is cured by exposing it to heat while in the presence of an AC magnetic field followed by a static, substantially homogeneous DC magnetic field.Type: GrantFiled: July 25, 2002Date of Patent: May 11, 2004Inventor: S. Kumar Khanna
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Patent number: 6696107Abstract: The present invention relates to a method for producing an ordered array of nanoparticles on a substrate surface and to a nanomaterial having such an ordered array of nanoparticles. Particularly, but not exclusively, the invention relates to the provision of an ordered array of magnetic nanocrystals on a substrate surface. Although the present invention is not limited to the production of a magnetic array, one important object of the present invention is the production of a material suitable for use as an ultra high density magnetic data storage medium. According to the present invention there is provided a method of producing a structure comprising a plurality of nanoparticles distributed across a surface of a substrate in a predetermined array, the method comprising the steps of: i) providing a substrate which has a passivated surface; ii) depositing nanoparticles on to said surface; and iii) displacing said particles over said surface to configure them in said predetermined array.Type: GrantFiled: May 5, 2003Date of Patent: February 24, 2004Assignee: Council for the Central Laboratory of the Research CouncilsInventor: Derek A. Eastham
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Patent number: 6632517Abstract: The magnetic and magnetotransport properties of field-aligned single domain half-metallic CrO2 powders have been studied. Needle-shaped nanoparticles of CrO2 have been aligned in a strong magnetic field. The aligned powder sample shows a strong anisotropy along the alignment direction. The conduction mechanism of the aligned CrO2 powder sample has been examined and is consistent with the intergranular spin dependent tunneling. Negative tunneling magnetoresistance (TMR) of about 41% is achieved in a small field in the vicinity of the coercive field at 5 K. The magnetoresistance (MR) versus field curve shows two well-separated narrow peaks at the coercive fields and resembles that of a magnetic tunnel junction. This junction-like MR results from the narrow switching field distribution of the aligned powders. The results suggest that the aligned magnetic CrO2 particles may find novel applications in spin transport structures and devices.Type: GrantFiled: August 21, 2001Date of Patent: October 14, 2003Assignee: University of New Orleans Research and Technology Foundation, Inc.Inventors: Jinke Tang, Jianbiao Dai
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Patent number: 6599583Abstract: A method for forming segmented through holes in a printed circuit board. The segmented through holes comprise a plurality of electrically conductive pathways disposed on the walls of a single through hole. The segmented through hole can be disposed in a two sided circuit board assembly or in a composite, multi layer circuit board assembly.Type: GrantFiled: September 27, 2001Date of Patent: July 29, 2003Inventor: N. Edward Berg
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Patent number: 6598425Abstract: A method and apparatus for manufacturing optical components. A burner generates soot, and a surface area collector collects the soot. The burner is disposed such that the soot collected within the surface area collector is substantially not reheated by subsequently deposited soot. Magnetic forces direct the soot to desired location(s) within the surface area collector. The surface area collector operates at relatively low temperatures sufficient to retain rather volatile substances, such as fluorine, in the soot.Type: GrantFiled: November 20, 2000Date of Patent: July 29, 2003Assignee: Corning IncorporatedInventors: Daniel W. Hawtof, Joseph M. Whalen
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Patent number: 6514575Abstract: Magnetic composites exhibit distinct flux properties due to gradient interfaces. The composites can be used to improve fuel cells and effect transport and separation of different species of materials. A variety of devices can be made utilizing the composites including a separator, a cell, an electrode for channeling flux of magnetic species, an electrode for effecting electrolysis of magnetic species, a system for channeling electrolyte species, a system for separating particles with different magnetic susceptibilities. Some composites can be used to make a dual sensor for distinguishing between two species of materials and a flux switch to regulate the flow of a redox species and a flux switch to regulate the flow of a chemical species. Some composites can control chemical species transport and distribution.Type: GrantFiled: June 8, 2001Date of Patent: February 4, 2003Assignee: University of Iowa Research FoundationInventors: Johna Leddy, Sudath Amarasinghe
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Patent number: 6458432Abstract: A process for producing a magnetic disk having a randomly oriented magnetic powder, comprises: applying a magnetic coating solution containing at least a magnetic powder to a web that is being continuously conveyed, so as to prepare a magnetic layer; applying a first external magnetic field to the magnetic layer while the magnetic layer is wet; and applying a second external magnetic field to the magnetic layer while the magnetic layer is wet, wherein: the first external magnetic field is applied with a set of a first pair of same-pole-opposed magnets with the web interposed therebetween and a second pair of same-pole-opposed magnets with the web interposed therebetween; the first and second pairs are provided on the same plane of the web and on two equal sides of an isosceles triangle so that a perpendicular line dropped from a base of the isosceles triangle forms a line perpendicular to a conveying direction of the web; and the second external magnetic field is an alternating magnetic field, and is appliedType: GrantFiled: November 26, 2001Date of Patent: October 1, 2002Assignee: Fuji Photo Film Co., Ltd.Inventors: Hitoshi Noguchi, Junichi Nakamikawa, Shinji Saito
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Patent number: 6403169Abstract: One aspect of the present invention provides a method of producing a security document, including the steps of: (a) forming a sheet-like substrate of plastics material having first and second opposing surfaces, (b) coating a first layer of polymer material containing magnetic particles on the first opposing surface, (c) melting at least a portion of the first layer such that the magnetic particles can orient under the influence of a magnetic field, (d) applying the magnetic field so as to form a magnetic watermark, and (e) allowing the first layer portion to cool so as to fix the orientation of the magnetic particlesType: GrantFiled: March 13, 2000Date of Patent: June 11, 2002Assignee: Securency Pty Ltd.Inventors: Bruce Alfred Hardwick, Gary Power
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Patent number: 6399280Abstract: According to the present invention there is provided a method for making a lithographic printing plate comprising the steps of applying a first magnetic field to a dry, light absorbing powder, which comprises a magnetic material and a hydrophobic thermoplastic binder, thereby coating said powder on a surface of a metal support; image-wise exposing to light the powder in contact with the surface of the metal support, thereby increasing the adhesion of the powder to the surface of the metal support, without substantially ablating the powder; and removing the non-exposed magnetic powder from the surface of the metal support under action of a second magnetic field with a polarity substantially opposite to the first magnetic field.Type: GrantFiled: October 24, 2000Date of Patent: June 4, 2002Assignee: Agfa-GevaertInventors: Joan Vermeersch, Augustin Meisters, Stefaan De Meutter
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Patent number: 6261647Abstract: A method for manufacturing a magnetic recording medium includes steps of forming a magnetic layer containing magnetic powder particles on a web-like non-magnetic support being continuously transported in one direction and applying a magnetic field to the magnetic layer by a plurality of magnets in such a manner that an angle of the magnetic field applied to the magnetic layer to the transporting direction of the non-magnetic support in a plane perpendicular to a surface of the magnetic layer and parallel to the transporting direction of the non-magnetic support gradually increases in the transporting direction of the non-magnetic support, thereby orienting the magnetic powder particles in an oblique direction with respect to the surface of the magnetic layer.Type: GrantFiled: January 25, 1996Date of Patent: July 17, 2001Assignee: Fuji Photo Film Co., Ltd.Inventors: Kazunori Komatsu, Norio Shibata
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Patent number: 6149857Abstract: An anisotropically-conductive film or a substrate having a surface coated with an anisotropically-conductive coating, said film or coating being formed by solidifying a composition comprising(i) a solidifiable ferrofluid composition, the ferrofluid comprising a colloidal suspension of ferromagnetic particles in a non-magnetic carrier, and(ii) a plurality of electrically-conductive particles, dispersed in the ferrofluid,the electrically-conductive particles having been arrayed in a non-random pattern by application of a substantially uniform magnetic field to the composition in a liquid state and having been locked in position by solidification of the composition.The composition is solidified in an A-stage, usually involving a primary cure. In end-use application of the film or coating, the composition usually undergoes a B-stage or secondary cure. The film or coated substrate is an article of manufacture for bonding conductors in the electronics industry.Type: GrantFiled: December 22, 1998Date of Patent: November 21, 2000Assignee: Loctite (R&D) LimitedInventors: Ciaran B. McArdle, Joseph Burke
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Patent number: 6120916Abstract: A composite magnetic material showing reduced losses and reduced permeability when it is subjected to a magnetic field at frequencies below approximately 100 MHz. It comprises magnetic particles in the form of wafers dispersed in a dielectric binder. The polycrystalline magnetic ceramic wafers are oriented so that their main faces are substantially parallel to the magnetic field.Application especially to cores of inductors or transformers.Type: GrantFiled: September 9, 1996Date of Patent: September 19, 2000Assignee: Thomson-CSFInventors: Jean-Pierre Delvinquier, Richard Lebourgeois, Michel Pate, Claude Rohart
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Patent number: 6120856Abstract: The invention relates to an improved method for the manufacture of magnetically responsive particles, also called ferrofluids. The improved method involves a heat treatment step, which may occur at various times during the preparation of the materials, including during subdivision of the magnetic starting material, during the addion of a coating material, after formation of a magnetically responsive particle, or some combination thereof. The materials formed by such a process have numerous advantages over materials formed by other processes, including enhanced salt stability, increased coating uptake, and increased binding capacity. These ferrofluids have applications in a variety of preparative and diagnostic techniques, including immunoassay, cell separations, toxicity testing, food testing, environmental analysis, and MRI.Type: GrantFiled: October 14, 1997Date of Patent: September 19, 2000Assignee: Immunivest CorporationInventors: Paul A. Liberti, Galla C. Rao, Joseph N. Chiarappa
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Patent number: 6110538Abstract: A method of making rotating element sheet material utilizing magnetic latching is provided. The first step is providing a sheet of sheet material comprising a substrate with a surface and rotatable elements disposed therein. The elements each have an optical and electrical anisotropy, and comprise at least two portions. One of the portions is magnetizable. After the magnetizable portions have been oriented in a common direction, they are magnetized substantially uniformly. The elements can be oriented such that the magnetized portions are disposed towards the surface of the substrate. A layer of hardenable mixture containing a plurality of magnetic particles is then applied to the surface of the substrate. The hardenable liquid is kept liquid for a period of time to allow the migration magnetic particles to the area of the layer in the vicinity of the magnetized portions of the rotatable elements.Type: GrantFiled: November 25, 1998Date of Patent: August 29, 2000Assignee: Xerox CorporationInventor: Nicholas K. Sheridon
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Patent number: 6103361Abstract: Smooth, patterned substrates useful in producing decorative cookware are formed by coating a base with a mixture of fluoropolymer and magnetic flakes and magnetically inducing an image in the polymer coating composition. The baked fluoropolymer release coating contains magnetizable flakes, a portion of the flakes being oriented in the plane of the substrate and a portion of said flakes being magnetically reoriented to form a pattern in the coating which is observed in reflected light, the flakes having a longest dimension which is greater than the thickness of said coating. The patterned substrate is formed by applying magnetic force through the edges of a magnetizable die positioned under a coated base to induce an imaging effect or pattern. The coating composition is then cured resulting in a smooth surface, patterned nonstick finish on the substrate.Type: GrantFiled: September 1, 1998Date of Patent: August 15, 2000Assignee: E. I. du Pont de Nemours and CompanyInventors: Kenneth Batzar, Jeffrey Hugh Hamilton, Alan C. Herzer, Thomas J. Leck, Christopher Mark Rey
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Patent number: 5981053Abstract: This invention relates to a magnetic stripe comprising a medium in which magnetized particles are suspended and in which the encoded information is recorded by actual physical rotation or alignment of the previously magnetized particles within the flux reversals of the stripe which are 180.degree. opposed in their magnetic polarity. The magnetized particles are suspended in a medium which is solid, or physically rigid, at ambient temperatures but which at moderately elevated temperatures, such as 40.degree. C., is thinable to a viscosity permissive of rotation of the particles therein under applications of moderate external magnetic field strengths within acceptable time limits.Type: GrantFiled: October 5, 1993Date of Patent: November 9, 1999Assignee: Sandia CorporationInventors: Richard Brian Naylor, Donald J. Sharp
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Patent number: 5943156Abstract: A polarizing plate includes a polarizing layer for controlling a light and producing a polarized light, the polarizing layer having a particle dispersing medium with a property of light transmission and bar-like polarizing particles which are dispersed in the particle dispersing medium and arranged in a constant direction with a magnetic field, where each of the bar-like polarizing particles is provided with a bar-like ferromagnetic particle of chromium dioxide, whose surface is coated with a conductive film.Type: GrantFiled: February 23, 1998Date of Patent: August 24, 1999Assignee: TDK CorporationInventors: Eiju Komuro, Tohru Kineri, Kouji Tanabe
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Patent number: 5939150Abstract: The present invention relates to a method for treating a substrate surface. The substrate surface is coated with a thin film of a treating agent, which is capable of enhancing or reducing its affinity towards a metal precursor by exposure to an arbitrary kind of radiation beam. In a subsequent metal deposition step utilizing the metal precursor, the metal is selectively deposited on the exposed or unexposed areas, depending on the kind of treating agent. (FIG.Type: GrantFiled: April 25, 1997Date of Patent: August 17, 1999Assignees: Max-Planck-Gesellschaft Zur Forderung Der Wissenschaften E.V., CNRS-Service De La ValorisationInventors: Martin Stelzle, Pascal Doppelt
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Patent number: 5763019Abstract: In a method of manufacturing magnetic recording medium, the position and operating condition and the like of an orienting device are determined so that a solvent weight ratio X satisfies 0.7.ltoreq.X.ltoreq.1.0.Type: GrantFiled: November 12, 1996Date of Patent: June 9, 1998Assignee: Kao CorporationInventors: Hiroki Miura, Masayasu Sato
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Patent number: 5698271Abstract: The invention relates to an improved method for the manufacture of magnetically responsive particles, also called ferrofluids. The improved method involves a heat treatment step, which may occur at various times during the preparation of the materials, including during subdivision of the magnetic starting material, during the addion of a coating material, after formation of a magnetically responsive particle, or some combination thereof. The materials formed by such a process have numerous advantages over materials formed by other processes, including enhanced salt stability, increased coating uptake, and increased binding capacity. These ferrofluids have applications in a variety of preparative and diagnostic techniques, including immunoassay, cell separations, toxicity testing, food testing, environmental analysis, and MRI.Type: GrantFiled: June 7, 1995Date of Patent: December 16, 1997Assignee: Immunivest CorporationInventors: Paul A. Liberti, Galla C. Rao, Joseph N. Chiarappa
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Patent number: 5633050Abstract: A method for producing a magnetic recording medium which results in the effective oblique orientation of magnetic fine particles without aggregation of the particles. The method results in a magnetic recording medium having an upper magnetic layer containing needle-shaped, granular, or plate-like magnetic particles, and at least one lower nonmagnetic layer formed on a nonmagnetic support so that the magnetic particles have the maximum degree of orientation in an oblique or perpendicular direction with respect to a surface of the support. The oblique or perpendicular orientation is performed in the wet state of a magnetic layer and in the condition in which the amount of the solvent residue in the upper magnetic layer is 40 to 80% after the upper magnetic layer and the lower nonmagnetic layer are applied sequentially or simultaneously to form a multilayer.Type: GrantFiled: July 11, 1995Date of Patent: May 27, 1997Assignee: Fuji Photo Film Co., Ltd.Inventors: Norio Shibata, Shinsuke Takahashi
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Patent number: 5601647Abstract: An improved extrusion coater having at least two coater slots for applying one or more magnetizable layers to a flexible nonmagnetic substrate is described. The upper lip of the outlet orifice is recessed relative to the lower lip and, in addition, the edge of a right parallelepiped magnet which has a gradient of more than 400 A/cm.sup.2 in the direction of the extruder slot, resulting in a stabilized liquid cushion, is arranged opposite the outlet orifice for the dispersions from the extrusion coater, on the other side of the substrate. It is thus possible to apply very thin layers and to make the meniscus insensitive to interfering forces. To reduce the edge bead, a stripping plate (13) which is extended beyond the range of the upper or lower lip of the extrusion coater, in the direction of the coated material web (1), is mounted at both coating edges, a minimum distance of from 0.05 to 0.8 mm between the surface (19) of the stripping plate (13) and the coated material web being established (FIG. 1).Type: GrantFiled: February 1, 1995Date of Patent: February 11, 1997Assignee: BASF Magnetics GmbHInventors: Albert Pertzsch, Reinhard Kraetschmer, Michael Breitsameter, Siegfried Rieger
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Patent number: 5512332Abstract: A method is provided for direct coating of transiently stable, colloidal particulate magnetic substrates with various synthetic or naturally-occurring polymers, particularly biologically-active peptides and proteins. The resulting coated resuspendable, colloidal magnetic particles are particularly adapted for use in bioanalytical procedures involving affinity separation, or the like. There is also provided a method for selectively binding chemically-treated colloidal magnetic particles to polyelectrolytes, e.g., to facilitate extraction of nucleic acids from cell lysates.Type: GrantFiled: April 22, 1994Date of Patent: April 30, 1996Assignee: Immunivest CorporationInventors: Paul A. Liberti, Steven P. Piccoli
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Patent number: 5427675Abstract: An article comprising a substrate formed with predetermined patterns and magnetized magnetic substances arranged in the substrate in accordance with the predetermined patterns, and a method of manufacturing an article with magnetized magnetic substances arranged according to predetermined patterns, comprising the steps of arranging said magnetic substances in a substrate in accordance with the predetermined patterns and magnetizing the magnetic substances.Type: GrantFiled: March 18, 1993Date of Patent: June 27, 1995Assignee: Teijin Seiki Co., Ltd.Inventors: Kiyoshi Toyama, Masayuki Togawa
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Patent number: 5268206Abstract: The present invention forms non-magnetic particles in a acicular shape as dispersed in a dispersoid liquid, forms a lower non-magnetic layer by coating the above-mentioned dispersoid liquid on a continually transported non-magnetic supporting base, forms an upper magnetic layer by coating the above-mentioned magnetic coating liquid in dual layers either consecutively or at the same time while the lower layer is still in its wet state, and performs an orientation of the magnetic particles by exposing the particles to a magnetic field while the dual layers as thus formed are still in their undried state. The orientation effect is achieved by making the specific gravity of the non-magnetic particles equal to or greater than that of the magnetic particles. The orientation effect is further enhanced by making the particle size of the non-magnetic particles equal to or less than that of the magnetic particles as measured along the long axis of the magnetic particles.Type: GrantFiled: August 24, 1992Date of Patent: December 7, 1993Assignee: Fuji Photo Film Co., Ltd.Inventors: Kazunori Komatsu, Mikio Tomaru
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Patent number: 5229173Abstract: A method of producing a coated magnetic recording medium includes a step of coating a nonmagnetic substrate with a magnetic paste layer mainly composed of acicular or granular magnetic particles and a resin binder, a spontaneous drying step for a specific period for inducing leveling of the coated surface and spontaneous volatilization of solvent without applying a magnetic field from outside after coating the magnetic paint, a first orientation step for dissipating the aggregated particles by a sudden change in magnetic field while inducing magnetic moment in magnetic particles by a strong DC magnetic field inside the coated surface and in a longitudinal direction of the medium for arraying the magnetic particles in the coated surface in the longitudinal direction, and a succeeding second orientation step for suppressing the magnetic repulsive force among the particles while arraying the magnetic particles by a DC magnetic field in the coated surface in the longitudinal direction.Type: GrantFiled: August 21, 1992Date of Patent: July 20, 1993Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Suzuki, Tousaku Nishiyama, Masaki Hirokoh, Tsumoru Ohata
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Patent number: 5180608Abstract: A coating type, magnetic disk is produced by applying a magnetic paint containing magnetic powders in a dispersed state to a non-magnetic substrate, thereby forming a magnetic recording film thereon, and applying surface waves to the magnetic recording film in an undried state. By applying the surface waves to the magnetic recording film, dispersibility and orientation of the magnetic powders are improved and a longitudinally oriented, coating type magnetic disk with distinguished electromagnetic properties, such as a high S/N ratio, etc. can be obtained.Type: GrantFiled: October 24, 1990Date of Patent: January 19, 1993Assignee: Hitachi, Ltd.Inventors: Katsuyoshi Chiba, Masayuki Katsumoto, Yasutaro Uesaka, Hajime Fukke, Heigo Ishihara, Iwao Matsuyama, Naoki Kodama, Hitoshi Inoue, Yoshiharu Terada
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Patent number: 5160761Abstract: Information is magnetically recorded in and reproduced from a magnetic disk using a flying magnetic head. The disk is a coating type disk comprising a rigid substrate having a magnetic layer coated thereont from a magnetic coating composition of ferromagnetic submicron particles in a binder. High density recording is possible when the substrate has a surface roughness Ra of up to 0.007 .mu.m, the magnetic layer has a thickness of up to 0.5 .mu.m, a surface roughness Ra of up to 0.005 .mu.m, and a porosity of 4 to 45%.Type: GrantFiled: March 24, 1992Date of Patent: November 3, 1992Assignee: TDK CorporationInventors: Keiji Koga, Jun-ichi Satoh, Kenji Yokoyama, Akinori Nisizawa, Yasumichi Tokuoka