Abstract: The present invention provides a method for producing an aluminate-based phosphor or a luminescent aluminate-based phosphor, which comprises calcining an aluminum compound having a BET specific surface area of 100 m2/g or more.

Abstract: A method of recovering a base phosphor from encapsulated phosphors, which comprises the steps of selecting a recovery vessel including a magnetic stir bar; adding to the recovery vessel, deionized water, a first batch of concentrated hydrochloric acid and encapsulated phosphor to form a stirred suspension; heating the stirred suspension to about 90° C. for about 2 hours; settling the stirred suspension; decanting the mother liquor and slurrying the remaining solids with a second batch of hydrochloric acid and water; decanting and washing the remaining solids with deionized water; filtering the remaining solids to form a filter cake; heating the filter cake at 110° C. in air for a time sufficient to form a dried filter cake; and screening the dried filter cake through a −325 mesh screen to yield a recovered base phosphor.

Abstract: Phosphor powders and a method for making phosphor powders. The powders are oxygen-containing, such as metal oxides, silicates, borates or titanates and have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the continuous production of such powders. The invention also relates to improved devices, such as display devices, incorporating the phosphor powders.

Abstract: A phosphor in the form of a columnar powder capable of exhibiting enhanced luminous efficiency, providing various luminous colors by electron excitation depending on the selection of elements added thereto and having improved life characteristics. The phosphor is made by heating a starting material constituted by a GaN based phosphor material to a temperature equal to or greater than a sublimation temperature thereof. The phosphor thus obtained is represented by Ga1−xInxN:A,B, wherein x is larger than or equal to 0 and smaller than 1 (0≦x<1), A is Zn or Mg, and B is Si or Ge.

Abstract: A luminescent nanophase binder is provided for use in UV and VUV applications. The binder promotes adherence of phosphor coatings to lamp envelopes and emits visible light under UV and VUV excitation. In a preferred embodiment, the binder comprises SiO2 nanoparticles doped with terbium or terbium and yttrium. Preferably, the nanoparticles have a particle size of less than 50 nm.

Abstract: A phosphor for a vacuum ultraviolet ray-exciting light-emitting element, comprising Eu as an activator, and aluminates having a magnetoplumbite structure.

Abstract: A method of preparing coprecipitated inorganic particles, including subjecting a first portion of an aqueous solution containing two or more metal ions to a coprecipitation reaction to form a liquid containing nucleus particles; mixing the nucleus particles-containing liquid with a second portion of the aqueous solution to form a mixture; and subjecting the mixture to a coprecipitation reaction to produce coprecipitated inorganic particles. The coprecipitated inorganic particles are calcined to obtain calcined inorganic particles having an average particle diameter of 0.5-10 &mgr;m.

Abstract: A yttrium silicate based phosphor and a method for synthesizing the phosphor by surface coating. The yttrium silicate based phosphor is synthesized by surface coating a Y2SiO5:Tb phosphor coated with a strontium (Sr)-thiogallate phosphor. In the method, Ga(NO3)3, Eu(NO3)3 and SrCO3 are mixed and stirred until the SrCO3 is completely dissolved. Next, a Y2SiO5:Tb phosphor is added to the mixture, and a sodium hydroxide (NaOH) is added to the mixture containing the Y2SiO5:Tb to adjust pH. Then, sulfur (S) is added to the pH-adjusted mixture. The sulfur containing mixture is dried, sieved, and fired at 750° C. for 4 hours.

Abstract: A novel phosphor represented by the general formula (Gd1−xCex)3Al5−yGayO12 (wherein x and y are values falling in the ranges of 0.0005≦x≦0.02, and 0<y<5.) was provided. The phosphor has a high luminous efficiency when Al and Ga are coexistent in the Gd-system phosphor. In particular, the phosphor with the Ga content (y) in the range of 2-3 has a luminous efficiency of twice the conventional phosphor. A radiation detector using this phosphor as ceramic scintillator is capable of obtaining a high luminous output and a very small afterglow.

Abstract: Disclosed is a green-emitting phosphor for a plasma display panel, represented by the formula 1: Ba1−xMnxAl12−yByO19  [Formula 1] wherein 0.001≦x≦0.5 and 0.01≦y≦1.0. The green-emitting phosphor has excellent color purity and luminance characteristics and shows an increased white color temperature of 9000 K or higher and a wide color reproducibility when it is applied to a plasma display panel, thereby improving picture quality characteristics.

Abstract: A fluorescent substance of the following general formula: LnXA1−XPO4 wherein Ln represents at least one element selected from the group consisting of Nd, Yb and Er; A represents at least one element selected from the group consisting of Y, La, Gd, Bi, Ce, LU, In and Tb; and X represents a value within the range of 0.01 to 0.99.

Abstract: Small particle manganese activated alkaline earth aluminate phosphors are produced by thermal decomposition of gels or powders comprising alkaline earth, manganese salts and an organic precursor such as aluminum isopropoxide at a temperature below the normal solid state reaction temperature. The phosphor of the present invention has the empirical formula: (AE1-xMnx)O·6(Al2O3) wherein AE is selected from Ba, Sr, Ca and Mg and 0.01≦×≦0.1, having a band emission in the green region, peaking at 516 nm when excited by 147 and 173 nm radiation from Xenon gas mixture. The phosphor obtained by the present method, having uniform particle size distribution (0.05 to 5 microns), is appropriate for thin phosphor screens required for a variety of flat panel display and lamp applications.

Abstract: A light-storing fluorescent pigment comprising a mother crystal and a rare earth element with which said mother crystal is doped, characterized in that said light-storing fluorescent pigment is produced by calcining a gel powder, as a starting material, obtained from an arbitrary combination of an alkoxide derivative, an organic acid salt, an inorganic acid salt, an oxide and a chloride of metal elements constituting said pigment by using a sol-gel method. A simplified production process can be used and the resulting light-storing fluorescent pigment has high crystal purity, is free from contamination with impurities and it is possible to easily control the particle diameter of the pigment.

Abstract: A method of making a YAG:Ce3+ phosphor includes adding an AlF3 fluxing agent to a yttrium, cerium, aluminum and oxygen containing starting powder and sintering the powder in a weak reducing atmosphere generated by evaporating charcoal. The resulting phosphor has a luminosity of greater than 435 lumens per watt.

Abstract: A Y(P,V)O4:Eu3+ red emitting phosphor is doped with at least one of a trivalent rare earth ion excluding Eu and a divalent metal ion to improve the lumen maintenance of the phosphor. The preferred material is the Y(P,V)O4:Eu3+ phosphor doped with trivalent Tb3+ ions and divalent Mg2+ ions.

Abstract: The present invention provides a novel orange light-emitting phosphorescent material that is non-toxic and chemically stable in air, and this invention relates to a Ti—CaO phosphorescent material, produced from a starting material of calcium oxide (CaO), or of calcium carbonate (CaCO3), calcium hydroxide(Ca(OH)2), calcium sulfate(CaSO4), calcium oxalate (CaC2O4), or other compound to be converted to CaO through heating in air, by a process of bringing this starting material into contact with metallic titanium (Ti) and conducting heat treatment thereof in vacuo or in an atmosphere that is not reactive with Ti such as argon gas, or by a process of mechanical alloying and the like of CaO and Ti.

Abstract: Nanocrystalline phosphors are formed within a bicontinuous cubic phase.

Abstract: The object of the present invention is to provide an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, whereby energy can be accumulated by radiation excitation, for example, by &ggr;-rays, X-rays, UV-rays, etc. and light emission can be continued for a long time even after stopping the excitation. That is, the present invention relates to an oxide glass capable of exhibiting a long lasting afterglow and photostimulated luminescence, characterized by a constitutional composition comprising, at least, terbium oxide (Tb2O3) or manganese oxide (MnO), gallium oxide (Ga2O3) or aluminum oxide (Al2O3), alkali metal oxide or alkaline earth metal oxide and boron oxide (B2O3) or silicon oxide (SiO2) or zinc oxide (ZnO).

Abstract: A phosphor is prepared by depositing a compound semiconductor of Groups III-V in the form of fine particles or a thin film on a surface of a carrier particle by hetero-epitaxial growth. Thus, the phosphor increased in quality is obtained with satisfactory reproducibility.

Abstract: A water-soluble semiconductor nanocrystal capable of light emission is provided. The nanocrystal including a semiconductor nanocrystal core having a selected band gap energy, a shell layer overcoating the core comprised of a semiconductor material having a band gap energy greater than that of the semiconductor nanocrystal, and an outer layer comprised of a molecule having at least one linking group for attachment of the molecule to the overcoating shell layer and at least one hydrophilic group optionally spaced apart from the linking group by a hydrophobic region sufficient to prevent electron charge transfer across the hydrophobic region.

Abstract: A terbium-samarium co-activated alkaline earth metal rare earth oxide phosphor which is composed of an oxygen atom and a composition of the formula (I): MIIMIII2:xTb,ySm  (I) [MII is Mg, Ca, Sr or Ba; MIII is Y, La, Gd or Lu; and x and y are numbers of 0<x≦0.1 and 0<y≦0.1] produces with time difference plural emissions having different colors by application of radiations such as X-rays and UV-light, so that the phosphor can be employed as a switching element or a display element giving color changing.

Abstract: Storage phosphors comprising an activated garnet host comprising oxygen and combined elements satisfying the relationship Ln3+&dgr;M5−&dgr;:cQ wherein Ln is an element selected from the group consisting of Gd, La, Lu, Y and combinations thereof; M is an element selected from the group consisting of Al, Ga, Sc, Fe and combinations thereof; Q is selected from the group consisting of terbium, samarium, thallium, indium, europium, ytterbium and combinations thereof; &dgr; is greater lo than or equal to minus 0.5, but less than or equal to 0.5 (i.e., −0.5≦&dgr;≦0.5); and c is an amount sufficient to produce a phosphor that exhibits a higher luminescence emission intensity than said phosphor absent Q when, after first being exposed to penetrating radiaton, the phosphor is stimulated by light of a wavelength ranging from 600 to 1200 nm or thermally.

Abstract: A fluorescent material is disclosed which is excellent in the intensity of color and brightness and suitable for a FED and a precise CRT. The fluorescent material is prepared by co-activating yttrium oxide fluorescent material activated with europium. The means particle size is 10 nm to 100 nm. To prepare the fluorescent material, basic carbonate activated with europium and zinc is used as a precursor which is then baked. The precursor is prepared by a liquid-phase reaction. Specifically, yttrium nitrate, europium nitrate and zinc acetate are allowed to react in a solution together with sodium carbonate. The prepared precursor is baked by a quick heating and cooling As an alternative to this, the precursor is baked together with flux (phosphate of alkali metal).

Abstract: A display screen comprising a phosphor composition which includes a phosphor and a phosphor coating with a group of metal-oxygen compounds, the group of metal-oxygen compounds containing an yttrium-oxygen compound, is characterized by a surprising improvement in picture brightness, color purity and adhesion of the phosphor composition to the glass of the display screen. The phosphor layer exhibits a high packing density of the phosphor material. The phosphor layer further exhibits a good homogeneity and is free from “pinholes”. In addition, the structured phosphor layer shows a high definition.

Abstract: A method for producing a trivalent rare earth ion-containing aluminate phosphor includes preparing a phosphor raw material comprising a granular aluminum containing compound in a phosphor raw material production process, heating the phosphor raw material in an oxidizing atmosphere at a predetermined temperature (e.g., 1500° C. to 1800° C.) so as to produce an intermediate phosphor in an intermediate phosphor production process. After the intermediate phosphor is cracked, the intermediate phosphor is heated in a reducing atmosphere at a predetermined temperature (e.g., 1400° C. to 1800° C.) in a trivalent rare earth ion-containing aluminate phosphor production process. The heating temperature in a reducing atmosphere is equal to or less than the heating temperature in an oxidizing atmosphere. A post treatment is performed, if necessary. Thus, a trivalent rare earth ion-containing aluminate phosphor can be obtained.

Abstract: Yttrium, gadolinium borate phosphor particles are produced by thermal decomposition of a xerogel or an aerogel including Rare Earth (yttrium, gadolinium and europium) and Alkaline Earth (barium, strontium, calcium, magnesium) salts. A sol-gel method is used and an organic precursor such as trimethyl borate obtains the respective xerogel or aerogel. Thermal decomposition of the gel takes place at a temperature well below the normal temperature of solid state reaction synthesis. The brightness of the final phosphor is improved by 5 to 10 by mixing the gel powder with respective nitrates thereof prior to calcination. The phosphor has the empirical formula: (Y1−x−y−z EuxGdy Mz)BO3 wherein: 0.01≦x≦0.1, 0≦y≦0.5, M=Ba/Sr/Ca/Mg and z≦0.1.

Abstract: Disclosed is a high-efficiency stress-luminescent material capable of emitting luminescence by receiving a mechanical stress such as compression, shearing and rubbing. The stress-luminescent material is an alkaline earth aluminate of a non-stoichiometric composition deficient in the content of the alkaline earth element by 0.01 to 20% by moles from stoichiometry. The efficiency of stress-luminescence emission can be further enhanced when the non-stoichiometric alkaline earth aluminate contains 0.01 to 10% by moles of rare earth metal ions or transition metal ions. The stress-luminescent material is prepared by subjecting a non-stoichiometric composite oxide of aluminum oxide and an alkaline earth oxide to a calcination treatment at 800 to 1700° C. in a reducing atmosphere.

Abstract: This invention relates to phosphors including long-persistence green phosphors. Phosphors of the invention are represented by the general formula: MkAl2O4:2xEu2+,2yR3+ wherein k−1-2x-2y, x is a number ranging from about 0.0001 to about 0.05, y is a number ranging from about x to about 3x, M is an alkaline earth metal, and R3+ is one or more trivalent metal ions. Phosphors of this invention include powders, ceramics, single crystals and single crystal fibers. A method of manufacturing improved phosphors and a method of manufacturing single crystal phosphors are also provided.

Abstract: A process for preparing a water resistant luminous pigment with durability, characterized in that a luminous pigment, in which an oxide matrix comprising at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn and at least one element selected from the group consisting of B, Al, P and Ga is doped with at least one rare-earth metal element, is allowed to an acid treatment under the condition of pH of not more than 3 using at least one acidic compound selected from the group consisting of acids and acid generating compounds, and is subsequently allowed to an alkaline treatment under the condition of pH 4-9 using at least one alkaline compound selected from the group consisting of alkalis and alkali generating compounds.

Abstract: There is provided a long-lasting phosphor being activated by divalent europium and having a chemical composition RO.a(Al1−xGax)2O3.bMmOn.cB2O3.dEu3+ (where R is at least one selected from the group consisting of alkaline-earth metals and Zn, and M is at least one selected from the group consisting of Y, Sc and Si) wherein a, b, c, d and x are within ranges of 0.3≦a≦8, 0<b≦0.2, 0.001≦c≦0.3, 0.001≦d≦0.3, and 0≦x<1.0.

Abstract: A phosphor comprises, in atomic percentages, 90% to 100% of a mixed metal oxide MxTyOz, wherein M is a metal selected from Zn, Sn, In, Cu, and combinations thereof, T is a refractory metal selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and combinations thereof, and O is Oxygen, x, y, and z being chosen such that z is at most stoichiometric for MxTyOz; and 0% to 10% of a dopant comprising a substance selected from a rare earth element of the lanthanide series, Mn, Cr, and combinations thereof, or stoichiometrically excess zinc, copper, tin, or indium. Cathodoluminescent phosphor compositions stimulable by electrons of very low energy are prepared from metal oxides treated with refractory metals in various processes disclosed.

Abstract: A luminescent material includes erbium, gadolinium and an activator chosen from the rare earth elements and/or the transition metals. Upon excitation with radiation having a short enough wavelength, the luminescent material acts as a quantum cutter and has a quantum efficiency of more than 100%.

Abstract: A water soluble semiconductor nanocrystal capable of light emission is provided, including a quantum dot having a selected band gap energy, a layer overcoating the quantum dot, the overcoating layer comprised of a material having a band gap energy greater than that of the quantum dot, and an organic outer layer, the organic layer comprising a compound having at least one linking group for attachment of the compound to the overcoating layer and at least one hydrophilic group spaced apart from the linking group by a hydrophobic region sufficient to prevent electron charge transfer across the hydrophobic region. The particle size of the nanocrystal core is in the range of about 12 Å to about 150 Å, with a deviation of less than 10% in the core. The coated nanocrystal exhibits photoluminescence having quantum yields of greater than 10% in water.

Abstract: A Li2SO4'Na2SO4 mixed flux for use in the synthesis of yttrium tantalate x-ray phosphors has been invented. The phosphors made with the mixed flux exhibit a dramatic increase XOF brightness, decreased persistence, and a reduced particle size.

Abstract: A phosphor comprises, in atomic percentages, 90% to 100% of a mixed metal oxide MxTyOz, wherein M is a metal selected from Zn, Sn, In, Cu, and combinations thereof, T is a refractory metal selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and combinations thereof, and O is Oxygen, x, y, and z being chosen such that z is at most stoichiometric for MxTyOz; and 0% to 10% of a dopant comprising a substance selected from a rare earth element of the lanthanide series, Mn, Cr, and combinations thereof, or stoichiometrically excess zinc, copper, tin, or indium. Cathodoluminescent phosphor compositions stimulable by electrons of very low energy are prepared from metal oxides treated with refractory metals in various processes disclosed.

Abstract: The present invention relates to a rare-earth borate, to a precursor thereof, to processes for their preparation and to the use of this borate as a luminophore. The rare-earth borate and the precursor thereof are characterized in that they are in the form of cubic, parallelepipedal or spherical particles and in that they have a dispersion index of not more than 0.8. According to one embodiment of the invention, the borate is a red luminophore. The process for the preparation of the precursor is characterized in that a rare-earth carbonate or hydroxycarbonate is reacted with boric acid, the reaction medium being in the form of an aqueous solution. The borate is obtained by calcination of the precursor.

Abstract: X-ray phosphor powders and a method for making phosphor powders. The phosphor powders have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the economic production of such powders. The invention also relates to improved devices, such as x-ray image intensifiers, incorporating the phosphor powders.

Abstract: A SrAl12O19 green luminescent material is doped with Mn2+ activator ions and at least one trivalent rare earth sensitizer ion species. Preferably, the material contains four rare earth ions: Ce3+, Pr3+, Gd3+ and Tb3+. Optionally, a portion of the aluminum may be substituted with magnesium. The material may be used as a display device or lamp phosphor or as an X-ray diagnostic or laser scintillator.

Abstract: This invention relates generally to new luminescent materials. Specifically, this invention relates to the discovery of phosphor materials in the forms of A2BX4, ABX4-y:M and A3-zB5X12:Mz. More specifically, this invention relates to the discovery of phosphor materials having compositions of matter in the forms, Sr2CeO4, (Y0.82Al0.07La0.06)VO4:Eu0.05 and (Y0.5Gd0.5)2.97(Al0.5Gd0.5)5O12:Ce0.03.

Abstract: Photoluminescent phosphor powders and a method for making phosphor powders. The phosphor powders have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the economic production of such powders. The invention also relates to improved devices, such as display devices and lighting elements, incorporating the phosphor powders.

Abstract: Electroluminescent phosphor powders and a method for making phosphor powders. The phosphor powders have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the economic production of such powders. The invention also relates to improved devices, such as electroluminescent display devices, incorporating the phosphor powders.

Abstract: A phosphor containing O, Al, In, at least one element M selected from a group consisting of Sr, Ca and Ba, and Eu, as an activator, where the M, the Al, the In and the Eu are present in an atomic ratio M:Al:In:Eu of m:2n(1−y):2n(y):a, 0.3<m/n≦2, 0≦y≦0.2, and 1×10−5≦a≦1×10−1, exhibits excellent luminance, afterglow and durability. Also a phosphor containing O, Al, In, B, at least one element M selected from a group consisting of Sr, Ca and Ba, and Eu2+ as an activator, where the M, the Al, the In, the B and the Eu are present in an atomic ratio M:Al:In:B:Eu of m:2n(1−y−z):2n(y−z):2n(z):a, 0.3≦m/n≦2, 0<y≦0.2, 0<z≦0.05, and 1×10−5≦a≦1×10−1 exhibits excellent luminance, afterglow and durability.

Abstract: A stable phosphor complex or blend includes a lanthanum phosphate phosphor with Tm3+ as an activator, Li+ and an optional amount of an alkaline earth element (AE2+) as a coactivator, having the empirical formula:: (La1-x-zTmxLiyAEz)PO4, wherein 0.001≦x≦0.05, 0.01≦y≦0.05, and 0≦z≦0.05; and 15 to 30% by weight of either: (i) divalent europium-activated barium, magnesium, aluminate (BAM), having an empirical formula: (Ba1-xEux)O MgyO (Al2O3)z, wherein 0.005≦x≦0.05 and 1≦y≦2; or (ii) divalent europium-activated barium, magnesium, lanthanum aluminate (BLMA), having an empirical formula: (Ba1-xEux)O MgyO (Al2-vLAvO3)z, wherein 0.005≦x≦0.05, 1≦y≦2, 5≦z≦7 and 0.1≦v≦1; or (iii) divalent europium activated alkaline earth chloro apatite (AECAP) having an empirical formula: (x.Sr,y.Ba,z.Cz,u.Mg)5(PO4)3Cl, wherein x+y+z+u=0.1, 0≦x≦1.0, 0≦y≦1.0, 0≦z≦1.0 and 0≦u≦1.

Abstract: Phosphor powders and a method for making phosphor powders. The powders are oxygen-containing, such as metal oxides, silicates, borates or titanates and have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the continuous production of such powders. The invention also relates to improved devices, such as display devices, incorporating the phosphor powders.

Abstract: A fluorescent material and a display device incorporating the fluorescent material are described. The fluorescent material is a mixture including a phosphor which is excitable at a voltage of 1 kV or higher for emitting light and a phosphor which is excitable at a voltage of 1 kV or lower for emitting light, wherein each phosphor emits light of the same color and the fluorescent material is luminous at an anode voltage of 2 kV or lower. The fluorescent display device accelerates electrons emitted from an electron source at an anode voltage of 2 kV or lower and rushes these electrons against an anode for exciting the fluorescent material present on the anode. The fluorescent material is a mixture as set forth above.