Abstract: One object of the present invention is to provide a lead-free piezoelectric material excellent in piezoelectric characteristics and superior from the viewpoints of prevention of environmental pollution, protection of environments and ecology. To achieve the object, a piezoelectric ceramic composition is constructed from a piezoelectric ceramic composition within a region in case of being represented by the formula:x[Bi.sub.1/2 Na.sub.1/2 ]TiO.sub.3 -y[MeNbO.sub.3 ]-(z/2)[Bi.sub.2 O.sub.3.Sc.sub.2 O.sub.3 ](wherein Me is K or Na)wherein X, y and z satisfy the following conditions:x+y+z=1, 0<x<1, 0.ltoreq.y<1, 0<z<0.5.
Abstract: A continuous automated process is provided for manufacturing a phosphor product having controlled particle size characteristics and enhanced luminescent performance characteristics for use in a luminescent display. A precursor host lattice solution, a precursor dopant solution and reagent solution are initially selected as the starting materials for the phosphor product and are mixed together to produce a liquid starting material mixture. The mixture is conveyed to a microwave reactor and heated therein in a first heating stage by subjecting the mixture to microwaves at a predetermined frequency for a time sufficient to convert the starting material mixture to a precursor complex. The precursor complex is conveyed to a fluidized bed reactor and heated therein in a second heating stage by a hot fluidizing gas for a time and at a temperature sufficient to convert the precursor complex to the phosphor product in particulate form.
Abstract: Small particle yttrium, gadolinium, terbium and cerium borate phosphors are produced by thermal decomposition of gels or solutions or powders containing yttrium, gadolinium, terbium and cerium salts and an organic precursor such as trimethyl borate or boric acid at a temperature below the normal temperature of solid state reaction. The phosphor of the present invention has the empirical formula:(Y.sub.1-x-y-z Gd.sub.x Tb.sub.y Ce.sub.z)BO.sub.3wherein: 0.0.ltoreq.x.ltoreq.0.2, 0.01.ltoreq.y.ltoreq.0.1, and 0.0.ltoreq.z.ltoreq.0.1.
Type:
Grant
Filed:
March 27, 1998
Date of Patent:
December 21, 1999
Assignee:
Matsushita Electric Industrial Co., Ltd.
Abstract: This invention involves new compositions and methods of use and delivery of amorphous calcium compounds such as: amorphous calcium phosphate (ACP), amorphous calcium phosphate fluoride (ACPF), amorphous calcium carbonate phosphate (ACCP), amorphous calcium carbonate phosphate fluoride (ACCPF), and amorphous calcium fluoride (ACF) for use in remineralizing and fluoridating teeth. These amorphous compounds or solutions which form the amorphous compounds or calcium phosphate jelly which forms the amorphous compounds, when applied either onto or into dental tissue to prevent and/or repair dental weaknesses such as dental caries, exposed roots and dentin sensitivity. The compounds have the highest solubilities, fastest formation rates and fastest conversion rates (to apatite) among all the calcium phosphates under physiological conditions. Moreover, in the presence to fluoride the amorphous compound convert rapidly to fluoride containing apatite.
Type:
Grant
Filed:
June 3, 1997
Date of Patent:
December 14, 1999
Assignee:
American Dental Association Health Foundation
Abstract: A method of the invention for manufacturing a rare earth bonded magnet has the steps of mixing a rare earth magnet powder, binder resin and an additive at a predetermined ratio, kneading the mixture at a temperature not lower than the thermal deformation temperature of the binder resin, granulating or graining the kneaded blend to granules of an average size ranging from 0.01 mm to 2 mm or so, conducting a compacting molding of the granulated material at a first temperature at which the binder resin is softened or molten, and cooling the molded body while keeping the molded body under pressure at least over a period in which the molded body cools down to a second temperature which s below the first temperature, whereby a rare earth bonded magnet is obtained having a low porosity, high dimensional precision and superior magnetic characteristic.
Type:
Grant
Filed:
March 10, 1998
Date of Patent:
December 14, 1999
Assignee:
Seiko Epson Corporation
Inventors:
Ken Ikuma, Takatomo Shinohara, Kiyoshi Shiohara
Abstract: A coating composition which imparts anti-reflective and anti-fog properties to substrates coated therewith. The coating composition utilizes an inorganic metal oxide in combination with particular anionic surfactants. The coating compositions are particularly useful in the manufacture of disposable surgical masks and face shields.
Type:
Grant
Filed:
October 7, 1998
Date of Patent:
December 7, 1999
Assignee:
Minnesota Mining and Manufacturing Co.
Inventors:
Matthew T. Scholz, William L. Kausch, David R. Boston, Joseph M. Zoborowski
Abstract: A polishing composition for polishing a memory hard disk comprising water and at least one abrasive selected from the group consisting of silicon dioxide, aluminum oxide, cerium oxide, zirconium oxide, titanium oxide, silicon nitride and manganese dioxide, which further contains an iron compound dissolved in the composition, said iron compound being selected from the group consisting of iron(III) nitrate, iron(III) sulfate, ammonium iron(III) sulfate, iron(III) perchlorate and an ion salt of an organic acid.
Abstract: A process is provided to prepare durable, high gloss titanium dioxide pigments by a continuous wet treatment process which involves curing of a silica coating at pH of between 7.0 and 8.5. Pigment prepared in this fashion is substantially free from Al(OH).sub.3 impurities and has excellent performance properties in high quality latex paint formulations.
Type:
Grant
Filed:
July 2, 1998
Date of Patent:
November 30, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Michael P Diebold, Charles Robert Bettler, Phillip Martin Niedenzu, Anhtony John Coombe, John Phillip Lanci, Sr.
Abstract: The present invention provides a piezoelectric ceramic having a low mechanical quality coefficient Qm and excellent heat resistance, for example, a piezoelectric ceramic for a filter element which can be applied to surface mounting. The piezoelectric ceramic contains at least a composite oxide of lead, zirconium and titanium, and oxides of manganese, silicon and boron, the concentration of the manganese oxide present in the crystal gain boundary being higher than that in crystal grains of the piezoelectric ceramic.
Abstract: A feldspathic porcelain composition is provided which comprises a continuous glassy matrix phase and a discontinuous, substantially uniformly dispersed cubic leucite crystalline phase, said composition possessing a fusion temperature of from about 800.degree. to about 1200.degree. C. Methods of making the feldspathic porcelain composition are also provided, said methods comprising the steps of forming an alkali aluminosilicate powder comprising SiO.sub.2, Al.sub.2 O.sub.3, K.sub.2 O and Na.sub.2 O and at least one metal salt of rubidium, cesium, calcium, strontium, barium or thallium; heating the powder to effect an exchange of alkali cations with metal cations derived from said metal salt to provide a feldspathic porcelain composition which comprises a continuous glassy matrix phase and a discontinuous crystalline phase comprising cubic leucite.
Abstract: A manganese-activated aluminate phosphor represented by the following compositional formula and a vacuum ultraviolet ray excitation type light-emitting element having this phosphor as a fluorescent layer:(1-a)(bMO.multidot.6Al.sub.2 O.sub.3).multidot.a(MMg.sub.1-c Mn.sub.c Al.sub.10 O.sub.17)wherein M is at least one member of Ba and Sr, and a, b and c are numbers satisfying the conditions of 0.05.ltoreq.a.ltoreq.1.0, 0.64.ltoreq.b.ltoreq.0.86, 0.05.ltoreq.c.ltoreq.1.0 and 0.05.ltoreq.a.times.c.ltoreq.0.
Abstract: Small particle lanthanum, thulium phosphate phosphors are produced by thermal decomposition of gels or solutions or powders including lanthanum, thulium, lithium and alkaline earth salts and an organic precursor such as trimethyl phosphate and boric acid at a temperature well below the normal temperature of solid state reaction. The phosphor of the present invention has the empirical formula:(La.sub.1-x-y-z Tm.sub.x Li.sub.y Sr.sub.z)PO.sub.4wherein: 0.001.ltoreq.x.ltoreq.0.05; 0.01.ltoreq.y.ltoreq.0.05; and 0.0.ltoreq.z.ltoreq.0.05and exhibits a narrow band emission in blue region, peaking at 453 nm when excited by 147 and 173 nm radiation from Xenon gas mixture. The phosphor exhibits uniform and spherical shape particles in the range 0.1 to 5 microns, and is appropriate for thin phosphor screens required for a variety of flat panel display and lamp applications. The particle size varies with method of preparation.
Type:
Grant
Filed:
July 6, 1998
Date of Patent:
November 23, 1999
Assignee:
Matsushita Electric Industrial Co., Ltd.
Abstract: Magnetorheological liquids, a process for producing them, their use and a process for producing polymer-coated magnetisable particles used in the magnetorheological liquids.
Type:
Grant
Filed:
November 24, 1997
Date of Patent:
November 23, 1999
Assignee:
G E Bayer Silicones GmbH & Co. KG
Inventors:
Wolfgang Podszun, Olaf Halle, Johan Kijlstra, Robert Bloodworth, Eckhard Wendt
Abstract: A magnetorheological (MR) fluid including magnetically soft particles suspended in a carrier solvent is disclosed. The MR fluid also includes additive particles of smaller size than the magnetically soft particles and a bridging polymer. The additive particles and polymer form a gel-like material which provides a blanket or coating around the magnetically soft particles. The MR fluids possess improved stability and redispersibility, as well as favorable mechanical properties.
Type:
Grant
Filed:
April 30, 1998
Date of Patent:
November 16, 1999
Assignee:
University of Pittsburgh of the Commonwealth System of Higher Education
Abstract: A method for forming a continuous, conformal non-particulate coating of boron oxide on individual phosphor particles is provided. The method involves reacting a boron-containing precursor with an oxidizing gas in a fluidized bed of phosphor particles. The boron oxide coated phosphor exhibits an increased quantum efficiency under ultraviolet (UV) and vacuum ultraviolet (VUV) excitation.
Type:
Grant
Filed:
August 19, 1998
Date of Patent:
November 16, 1999
Assignee:
Osram Sylvania Inc.
Inventors:
Chen-Wen Fan, Dale E. Benjamin, Franz Kummer, Charles F. Chenot, Richard G. W. Gingerich
Abstract: Improved zinc orthosilicate phosphor particles are produced by thermal decomposition of gels comprising zinc and manganese salt and an organic precursor that provides a source of silicon at a temperature below the temperature of solid state reaction. The phosphor of the present invention has the empirical formula:Zn.sub.(2-x) Mn.sub.x SiO.sub.4wherein 0.005.ltoreq.x.ltoreq.0.15, and provides a broad emission in a green region when excited by 147 nm and 172 nm radiation. The phosphor obtained by the present method has uniform spherical or needle shape particles having an average particle size in the range 0.1 to 3 microns, is appropriate for thin phosphor screens required for a variety of flat panel display and lamp applications. These phosphors exhibit high brightness and shorter decay when excited with 147 nm and 172 nm radiation than currently available commercial phosphors of this type.
Type:
Grant
Filed:
December 4, 1997
Date of Patent:
November 16, 1999
Assignee:
Matsushita Electric Industrial Co., Ltd.
Abstract: Phosphors having a doped core are surrounded by a shell material. Additionally, these nanocrystalline phosphors, or larger phosphors formed by conventional or other processes may be surrounded by a shell that prevents or significantly reduces non-radiative recombination at the surface of the original phosphor.
Type:
Grant
Filed:
November 18, 1997
Date of Patent:
November 16, 1999
Inventors:
Henry F. Gray, Jianping Yang, David S. Y. Hsu, Banhalli R. Ratna
Abstract: Disclosed are an organic electroluminescence device having at least a light emitting layer between the electrodes consisting of one pair of an anode and a cathode, at least one of which electrodes is transparent or semi-transparent, wherein said light emitting layer comprises a polymeric fluorescent substance which emits a fluorescence in a solid state, is soluble in solvents and comprises at least one kind of repeating unit represented by the following formula (1) and at last one kind of repeating unit represented by the following formula (2) with the number of the formula (1) repeating units being 2-50% of the total number of all the repeating units:--Ar.sub.1 -- (1)--Ar.sub.2 -- (2)wherein Ar.sub.1 and Ar.sub.2 are each a bifunctional group forming a carbon--carbon bond with each of two adjacent groups, in the chemical structure of Ar.sub.
Abstract: The manganese-zinc system ferrite of the invention has an initial permeability .mu.i at a frequency of 100 kHz and at 25.degree. C. of 5,000 or more, and a core loss Pcv at a frequency of 100 kHz and at 200 mT and 40.degree. C. of 400 kW/m.sup.3 or less.
Abstract: Described is an inorganic fiber comprising silica dioxide, calcium oxide, and alkali oxide having a free energy of hydration greater than (more positive than) -5.00 kcal/mol, an enthalpy of formation less than (more than negative than) -210.0 kcal/mol, a dissolution rate in simulated extra cellular fluid greater than 750 (calculated as nanograms of fiber/per square centimeter of fiber surface area/per hour) having an average fiber diameter not greater than 4.5 micrometers. Also described is a method of manufacturing the fibers.