Sulfur Containing Patents (Class 252/301.6S)
  • Patent number: 7695642
    Abstract: A method is provided for preparing luminescent semiconductor nanoparticles composed of a first component X, a second component A, and a third component B, wherein X, A, and B are different, by combining B with X and A in an amount such that the molar ratio B:(A+B) is in the range of approximately 0.001 to 0.20 and the molar ratio X:(A+B) is in the range of approximately 0.5:1.0 to 2:1. The characteristics of the thus-prepared nanoparticles can be substantially similar to those of nanoparticles containing only X and B while maintaining many useful properties characteristic of nanoparticles containing only X and A. The nanoparticles so prepared can additionally exhibit emergent properties such as a peak emission energy less than that characteristic of a particle composed of XA or XB alone; this method is particularly applicable to the preparation of stable, bright nanoparticles that emit in the red to infrared regions of the electromagnetic spectrum.
    Type: Grant
    Filed: December 13, 2004
    Date of Patent: April 13, 2010
    Assignee: Life Technologies Corporation
    Inventors: Marc D. Schrier, Donald A. Zehnder, Joseph A. Treadway, Joseph A. Bartel
  • Publication number: 20100044636
    Abstract: A semiconductor nanocrystal including a core comprising a first semiconductor material comprising at least three chemical elements and a shell disposed over at least a portion of the core, the shell comprising a second semiconductor material, wherein the semiconductor nanocrystal is capable of emitting light with an improved photoluminescence quantum efficiency. Also disclosed are populations of semiconductor nanocrystals, compositions and devices including a semiconductor nanocrystal capable of emitting light with an improved photoluminescence quantum efficiency. In one embodiment, a semiconductor nanocrystal includes a core comprising a first semiconductor material comprising at least three chemical elements and a shell disposed over at least a portion of the core, the shell comprising a second semiconductor material, wherein the semiconductor nanocrystal is capable of emitting light upon excitation with a photoluminescence quantum efficiency greater than about 65%.
    Type: Application
    Filed: May 21, 2009
    Publication date: February 25, 2010
    Inventors: Dorai Ramprasad, Craig Breen, Jonathan S. Steckel
  • Publication number: 20100044635
    Abstract: A semiconductor nanocrystal capable of emitting blue light upon excitation. Also disclosed are devices, populations of semiconductor nanocrystals, and compositions including a semiconductor nanocrystal capable of emitting blue light upon excitation. In one embodiment, a semiconductor nanocrystal capable of emitting blue light including a maximum peak emission at a wavelength not greater than about 470 nm with a photoluminescence quantum efficiency greater than about 65% upon excitation. In another embodiment, a semiconductor nanocrystal includes a core comprising a first semiconductor material comprising at least three chemical elements and a shell disposed over at least a portion of the core, the shell comprising a second semiconductor material, wherein the semiconductor nanocrystal is capable of emitting blue light with a photoluminescence quantum efficiency greater than about 65% upon excitation.
    Type: Application
    Filed: May 21, 2009
    Publication date: February 25, 2010
    Inventors: Craig Breen, Jonathan S. Steckel, Dorai Ramprasad
  • Publication number: 20090230357
    Abstract: An electroluminescent phosphor comprising ZnS:Mn is disclosed. Also disclosed are ZnS:Mn electroluminescent phosphors that are free of or substantially free of copper, and/or wherein the phosphor has a D50 size of less than about 5 ?m. In addition, a method for preparing a ZnS:Mn phosphor is disclosed, comprising the steps of contacting at least a portion of each of a first solution comprising a Zn2+ compound, a manganese source, and a second solution comprising a S2? source agent; and then heating the mixture at a temperature and for a time sufficient to form a phosphor.
    Type: Application
    Filed: March 11, 2009
    Publication date: September 17, 2009
    Inventors: Xianzhong Chen, Shellie Kaye Northrop, Chen-Wen Fan
  • Publication number: 20090212256
    Abstract: A copper activated zinc sulfide electroluminescent phosphor is disclosed, wherein the phosphor comprises greater than about 1,000 ppm copper. Also disclosed is a copper activated zinc sulfide electroluminescent phosphor having a y color coordinate of at least about 0.480. A method for preparing the copper activated zinc sulfide electroluminescent phosphor is disclosed, comprising contacting a zinc sulfide, a first copper source, a magnesium source, and a lithium halide to form a first mixture; heating the mixture at a temperature and for a time sufficient to form a fired mixture; subjecting the fired mixture to a shear force capable of inducing a plurality of defects in the zinc sulfide lattice structure; and then contacting the fired mixture with a second copper source and a zinc oxide to form a second mixture; heating the second mixture at a temperature and for a time sufficient to form a second-fired material.
    Type: Application
    Filed: February 26, 2009
    Publication date: August 27, 2009
    Inventors: Gregory Allan Marking, Xianzhong Chen, Shellie Kaye Northrop
  • Publication number: 20090166587
    Abstract: To produce fluorescent bodies providing high brightness and high energy efficiency, a method of preparing a fluorescent body precursor is provided to enable an activator having a large ionic radius to be doped arbitrarily. The problems described above are solved by a method of preparing a fluorescent body precursor, which method is characterized by comprising applying a shock pressure of 0.1 GPa or higher to a mixture consisting essentially of a fluorescent body base, an activator, and a co-activating particle-growth promoter to dope the activator into the fluorescent body base in the presence of the co-activating particle-growth promoter.
    Type: Application
    Filed: July 26, 2007
    Publication date: July 2, 2009
    Applicant: Kuraray Luminas Co., Ltd
    Inventors: Yoshihisa Tsuji, Hideharu Iwasaki
  • Publication number: 20090159849
    Abstract: To provide a fluorescent having low toxicity and high quantum yield, and a method for producing the same. The fluorescent is a compound comprising each one of I, III and VI group elements having a chalcopyrite structure, has a particle diameter of 0.5 to 20.0 nm and a quantum yield of at least 3% but not more than 30% at room temperature. The fluorescent is produced by: mixing a first solution (solution A), which is prepared by dissolving and mixing copper (I) salt and indium (III) salt in a solution added with a complexing agent coordinating copper (I) and indium (III), with a second solution (solution C) in which a sulfur compound is dissolved; ripening the mixed solution for a predetermined amount of time as a pretreatment; heat-treating the ripened solution under predetermined heat conditions; mixing the ripened solution with the second solution (solution C); and heating thus obtained mixed solution under predetermined synthesis conditions.
    Type: Application
    Filed: November 17, 2006
    Publication date: June 25, 2009
    Applicant: National Institute of Advanced Industrial Science and Technology
    Inventors: Masato Uehara, Hiroyuki Nakamura, Hideaki Maeda, Masaya Miyazaki, Yoshiko Yamaguchi, Kenichi Yamashita
  • Publication number: 20090121190
    Abstract: The present invention provides matrixes doped with semiconductor nanocrystals. In certain embodiments, the semiconductor nanocrystals have a size and composition such that they absorb or emit light at particular wavelengths. The nanocrystals can comprise ligands that allow for mixing with various matrix materials, including polymers, such that a minimal portion of light is scattered by the matrixes. The matrixes of the present invention can also be utilized in refractive index matching applications. In other embodiments, semiconductor nanocrystals are embedded within matrixes to form a nanocrystal density gradient, thereby creating an effective refractive index gradient. The matrixes of the present invention can also be used as filters and antireflective coatings on optical devices and as down-converting layers. The present invention also provides processes for producing matrixes comprising semiconductor nanocrystals.
    Type: Application
    Filed: February 28, 2008
    Publication date: May 14, 2009
    Applicant: NANOSYS, INC.
    Inventors: J. Wallace Parce, Jian Chen, Robert S. Dubrow, William P. Freeman, Erik C. Scher, Jeffery A. Whiteford
  • Publication number: 20090108235
    Abstract: The present invention provides semiconductor-nanoparticle-dispersed small silica glass particles that emit bright fluorescent light with high fluorescence quantum yield and high density, compared to the conventional semiconductor-nanoparticle-dispersed small glass particles, and that have excellent fluorescence intensity stability over time; and a process for preparing the same. The semiconductor-nanoparticle-dispersed silica glass particles have a mean particle size of not less than 10 nanometers and not more than 5 micrometers, and contain a hydrolyzed alkoxide and semiconductor nanoparticles at a concentration of not less than 2×10?5 mol/l and not more than 1×10?2 mol/l. The particles emit fluorescent light with a fluorescence quantum yield (quantum yield) of 25% or more (and 60% or more), when dispersed in a solution.
    Type: Application
    Filed: September 21, 2006
    Publication date: April 30, 2009
    Applicant: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Masanori Ando, Norio Murase, Chunliang Li, Ping Yang
  • Publication number: 20090039316
    Abstract: A doped-type metal sulfide phosphor nanoparticle, whose surface is modified with a surface modifier, the surface modifier being a compound of formula [I]: HS-L-W??Formula [I] wherein L is a divalent linking group; and W is COOM or NH2, in which M is a hydrogen atom, an alkali metal atom, or NX4, in which X is a hydrogen atom or an alkyl group; a dispersion containing the nanoparticle; and a method of producing the nanoparticle or the dispersion.
    Type: Application
    Filed: October 3, 2008
    Publication date: February 12, 2009
    Applicant: FUJIFILM CORPORATION
    Inventors: Hiroyuki HIRAI, Keiko SUGIHARA, Junji NISHIGAKI
  • Patent number: 7470379
    Abstract: The ionic conjugates include an inorganic particle electrostatically associated with a macromolecule which can interact specifically with predetermined chemical species or biological targets.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: December 30, 2008
    Assignees: Massachusetts Institute of Technology, The United States of America as represented by the Secretary of the Navy
    Inventors: George P. Anderson, Hedi Mattoussi, J. Matthew Mauro, Moungi G. Bawendi, Vikram C. Sundar
  • Patent number: 7462300
    Abstract: A doped-type metal sulfide phosphor nanoparticle, whose surface is modified with a surface modifier, the surface modifier being a compound of formula [I]: HS-L-W??Formula [I] wherein L is a divalent linking group; and W is COOM or NH2, in which M is a hydrogen atom, an alkali metal atom, or NX4, in which X is a hydrogen atom or an alkyl group; a dispersion containing the nanoparticle; and a method of producing the nanoparticle or the dispersion.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: December 9, 2008
    Assignee: FujiFilm Corporation
    Inventors: Hiroyuki Hirai, Keiko Sugihara, Junji Nishigaki
  • Publication number: 20080237540
    Abstract: The present invention provides methods for hermetically sealing luminescent nanocrystals, as well as compositions and containers comprising hermetically sealed luminescent nanocrystals. By hermetically sealing the luminescent nanocrystals, enhanced lifetime and luminescence can be achieved.
    Type: Application
    Filed: March 19, 2008
    Publication date: October 2, 2008
    Applicant: NANOSYS, Inc.
    Inventor: Robert S. Dubrow
  • Patent number: 7326366
    Abstract: A method of producing inorganic semiconductor- and phosphor-primary particles, which each comprises forming the particles by reacting at least one kind of precursor solution of the inorganic primary particle in a solvent, of which major component is water of a reacting vessel, under the conditions that the pressure is 0.2 to 20 MPa and the temperature is 120° C. to 370° C.; and inorganic semiconductor- and phosphor-primary particles produced by the method.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: February 5, 2008
    Assignee: Fujifilm Corporation
    Inventors: Satoshi Aiba, Shigeharu Urabe
  • Patent number: 7297295
    Abstract: A novel highly bright mechanoluminescence material free from decay of luminescence brightness even if repeated stress is applied, comprising a composite semiconductor crystal of the general formula xM1A1.(1-x)M2A2 (wherein each of M1 and M2 independently represents an atom selected from among Zn, Mn, Cd, Cu, Eu, Fe, Co, Ni, Mg and Ca, and each of A1 and A2 is an atom independently selected from among chalcogens, provided that M1A1 is different from M2A2; and x is a positive number less than 1); and a process for producing the same.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: November 20, 2007
    Assignees: Japan Science and Technology Agency, National Institute of Advanced Science and Technology
    Inventors: Chao-Nan Xu, Morito Akiyama, Wensheng Shi
  • Patent number: 7291291
    Abstract: There is presented an electroluminescent phosphor powder of copper-activated zinc sulfide particles that has a size distribution with a D50 value of less than 12 ?m, and more preferably less than 10 ?m. The powder is preferably made by a method that includes the steps of combining copper-doped zinc sulfide with sulfur, zinc oxide and a chloride-containing flux to form a first mixture; preliminarily firing the first mixture and milling the preliminarily fired first mixture to form a milled material having a D50 value of less than or equal to about 5 ?m; blending the milled material with sulfur, zinc oxide and a chloride-containing flux to form a second mixture; firing the mixture in a first firing step at a temperature in a range of about 1020° C. to about 1080° C. to form a hexagonal zinc sulfide material; inducing defects into the hexagonal zinc sulfide material; firing the hexagonal zinc sulfide material in a second firing step at a temperature in a range of about 650° C. to about 850° C.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: November 6, 2007
    Assignee: Osram Sylvania Inc.
    Inventors: Judy A. Belinski-Wolfe, Thomas A. Wolfe, Brian J. Payne
  • Patent number: 7288216
    Abstract: An electroluminescent phosphor powder includes copper-activated zinc sulfide particles that have a size distribution with a D50 value of no more than 10 ?m, where no more than 25% of the particles have a size greater than about 15 ?m and/or a 24-hr brightness of at least 15 footlamberts. These particles are made by a method that includes first firing copper-doped zinc sulfide mixed with zinc oxide, sulfur and a chloride-containing flux, rapidly cooling the mixture to below 100° C., and then mulling and second firing the mixture to provide a powder. The powder can then be elutriated to provide the electroluminescent powder with a narrow particle size distribution (more than 90% between about 5 and 15 ?m). The elutriating step can be avoided (albeit with a slightly wider size distribution) by more tightly controlling the first firing temperature.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: October 30, 2007
    Assignee: Osram Sylvania Inc.
    Inventors: Xianzhong Chen, Shellie K. Northrop
  • Patent number: 7264751
    Abstract: A yellow ZnS-based phosphor having improved color coordinates and luminance for use in intermediate- and low-voltage display devices using improved activators and coactivators has color coordinates (x, y) shifting to a yellow emission as the amount of an activator is increased. Therefore, the ZnS: (Au or Cu), In phosphor can be advantageously utilized for various display applications including vacuum fluorescent displays (VFDs) and field emission displays (FEDs).
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: September 4, 2007
    Assignee: Samsung SDI Co., Ltd.
    Inventors: Sanghyuk Lee, Sanghoon Shin, Yongchan You, Joayoung Jeong
  • Patent number: 7261838
    Abstract: The electroluminescent phosphor of this invention is comprised of zinc sulfide activated with copper and iodine and may produce an emission with an x color coordinate from 0.145 to 0.155 and a y color coordinate from 0.085 to 0.095. The phosphor preferably contains from about 0.08 to about 0.90 weight percent (wt. %) copper.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: August 28, 2007
    Assignee: Osram Sylvania Inc.
    Inventors: Judy A. Belinski-Wolfe, Brian J. Payne
  • Patent number: 7252790
    Abstract: Zinc sulfide electroluminophores are prepared from solutions of zinc salts with hydrogen sulfide. The zinc sulfide compounds are mixed with activator and coactivator compounds to produce luminophores, and the mixtures are fired in the presence of fixing agents. These fired materials are then treated in an acid bath, washed, neutralized, and optionally filtered and dried.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: August 7, 2007
    Assignees: Leuchtstoffwerk Breitungen GmbH, Bundesdruckerei GmbH
    Inventors: Frank Kappe, Benedikt Ahlers, Arnim Franz-Burgholz, Hans-Jurgen Limburg, Detlef Starick, Monika Voh
  • Patent number: 7235190
    Abstract: A method for making a nanocrystal-based material capable of emitting light over a sufficiently broad spectral range to appear white. Surface-modifying ligands are used to shift and broaden the emission of semiconductor nanocrystals to produce nanoparticle-based materials that emit white light.
    Type: Grant
    Filed: September 2, 2004
    Date of Patent: June 26, 2007
    Assignee: Sandia Corporation
    Inventors: Jess P. Wilcoxon, Billie L. Abrams, Steven G. Thoma
  • Patent number: 7135130
    Abstract: The invention provides electroluminescent phosphor having superior luminance and a long life. The host material is ZnS.aAO, of which “A” is at least one element selected from among magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). “a” ranges from 0.001 to 0.01. Either one of or both copper (Cu) or manganese (Mn) is contained as an activator. At least one element selected from among chlorine (Cl), bromine (Br), iodine (I), and aluminum (Al) is contained as a co-activator. The luminance and life span of the electroluminescent phosphor can be increased by limiting “a”, which represents the proportion of alkaline earth metal oxide (AO) introduced into the zinc sulfide, within the range of 0.001 to 0.01.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: November 14, 2006
    Assignee: Nemoto & Co. Ltd.
    Inventors: Junya Watabe, Yoshiki Kanno, Shigenobu Matsumura
  • Patent number: 7067072
    Abstract: The present invention relates in general to nanoparticles exhibiting luminescence such as photostimulated luminescence or photoluminescence and optical switching processes based upon such properties, in more particular, the use of such photostimulated luminescence exhibiting nanoparticles and switching nanoparticle for optical storage apparatuses and sensors as well as methods of making and using same.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: June 27, 2006
    Assignee: Nomadics, Inc.
    Inventor: Wei Chen
  • Patent number: 7067073
    Abstract: A yellow ZnS-based phosphor which has improved color coordinates and luminance for use in intermediate- and low-voltage display devices using improved activators and coactivators is a (ZnS: Mn, Cu) phosphor which has color coordinates (x, y) shifting to a yellow emission as the amount copper added as an activator is increased. The phosphor has enhanced luminance by adding a trivalent metal as a coactivator. Therefore, the (ZnS: Mn, Cu) phosphor can be advantageously utilized for various display applications including vacuum fluorescent displays (VFDs) and field emission displays (FEDs).
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: June 27, 2006
    Assignee: Samsung SDI Co., Ltd.
    Inventors: Sanghyuk Lee, Kyuchan Park, Sanghoon Shin, Yongchan You, Joayoung Jeong
  • Patent number: 7067071
    Abstract: Zinc sulfide electroluminophores are prepared from solutions of zinc salts with hydrogen sulfide. The zinc sulfide compounds are mixed with activator and coactivator compounds to produce luminophores, and the mixtures are fired in the presence of fixing agents. These fired materials are then treated in an acid bath, washed, neutralized, and optionally filtered and dried.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: June 27, 2006
    Assignees: Bundesdruckeri GmbH, Leuchtstoffwerk Breitungen GmbH
    Inventors: Frank Kappe, Benedikt Ahlers, Arnim Franz-Burgholz, Hans-Jürgen Limburg, Detlef Starick, Monika Voh
  • Patent number: 7014793
    Abstract: A method of making zinc sulfide based electroluminescent phosphors is described wherein a first-fired zinc sulfide material having a hexagonal ?-ZnS crystal structure is at least partially converted to a distorted hexagonal ?-ZnS crystal structure by ultrasonic irradiation. The first-fired material is then fired at a lower temperature to form an electroluminescent phosphor.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: March 21, 2006
    Assignee: OSRAM SYLVANIA Inc.
    Inventors: Charles F. Chenot, Judy A. Belinski-Wolfe, Fuquiang Huang
  • Patent number: 7008559
    Abstract: The present relates in general to upconversion luminescence (“UCL”) materials and methods of making and using same and more particularly, but not meant to be limiting, to Mn2+ doped semiconductor nanoparticles for use as UCL materials. The present invention also relates in general to upconversion luminescence including two-photon absorption upconversion, and potential applications using UCL materials, including light emitting diodes, upconversion lasers, infrared detectors, chemical sensors, temperature sensors and biological labels, all of which incorporate a UCL material.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: March 7, 2006
    Assignee: Nomadics, Inc.
    Inventor: Wei Chen
  • Patent number: 7005086
    Abstract: A fluorescent substance is obtained by weighing and mixing CaS, Ga2S3, EuS and Ce2S3 in a mole ratio of (1-x):a:x:y (wherein 0.001?x?0.2, 0.0001?y?0.02 and 0.5?a?5) and by sintering the mixture. A light-emitting diode comprises an LED chip 2 and an LED chip sealing portion 5, made of silicone resin and including the fluorescent substance, for enclosing the LED chip 2. Hence, a fluorescent substance that is excited by light having a predetermined wavelength to emit light, a light-emitting diode having excellent luminous efficiency and luminous intensity, and a method for producing the fluorescent substance are attained by the present invention.
    Type: Grant
    Filed: November 6, 2003
    Date of Patent: February 28, 2006
    Assignee: Seiwa Electric Mfg. Co., Ltd.
    Inventor: Kenji Matsuno
  • Patent number: 6921496
    Abstract: The ionic conjugates include an inorganic particle electrostatically associated with a macromolecule which can interact specifically with predetermined chemical species or biological targets.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: July 26, 2005
    Assignees: Massachusetts Institute of Technology, The United States of Americas as represented by the Secretary of the Navy
    Inventors: George P. Anderson, Hedi Mattoussi, J. Matthew Mauro, Moungi G. Bawendi, Vikram C. Sundar
  • Patent number: 6869545
    Abstract: The present invention provides new compositions containing colloidal nanocrystals with high photoluminescence quantum yields, new synthetic methods for the preparation of highly luminescent colloidal nanocrystals, as well as methods to control the photoluminescent properties of colloidal nanocrystals. The new synthetic methods disclosed herein allow photoemission brightness (quantum yield) to be correlated with certain adjustable nanocrystal growth parameters associated with a given synthetic scheme.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: March 22, 2005
    Assignee: The Board of Trustees of the University of Arkansas
    Inventors: Xiaogang Peng, Lianhua Qu
  • Patent number: 6833086
    Abstract: A phosphor powder is composed of a host material made of an element coming under the group II of the periodic table and an element coming under the group VI of the periodic table, an activator and a co-activator, the amount ratio of the activator to the host material is 1×10−4 to 1×10−3 parts by weight when the amount ratio of the host material is 1 part by weight, and the co-activator has a molar concentration equal to a molar concentration of the activator.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: December 21, 2004
    Assignee: Sony Corporation
    Inventor: Kazuo Kajiwara
  • Patent number: 6787064
    Abstract: An improved method for the preparation of a dispersion of ZnS particles doped with copper is disclosed. The method comprises the step of performing a precipitation by mixing together a zinc salt, a sulfide, and a citrate or EDTA complex of copper ions, dissolved in several aqueous solutions. Enhanced luminescence is obtained.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: September 7, 2004
    Assignee: AGFA Gevaert
    Inventor: Hieronymus Andriessen
  • Patent number: 6770221
    Abstract: A single-component white-emitting electroluminescent phosphor and its method of making are described. The single-component phosphor exhibits a white emission having an x color coordinate of 0.23 to 0.41 and a y color coordinate of 0.25 to 0.42. The phosphor is comprised of zinc sulfide activated with copper, manganese, chlorine, and, optionally, one or more metals selected from gold and antimony.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: August 3, 2004
    Assignee: Osram Sylvania Inc.
    Inventors: Xianzhong Chen, Robert L. Stevens
  • Patent number: 6682664
    Abstract: An orange-yellow-emitting zinc sulfide-based electroluminescent phosphor is described wherein the phosphor has a brightness of greater than 10 foot-Lamberts. More particularly, the phosphor has a brightness of at least about 13 foot-Lamberts and an x color coordinate from about 0.51 to about 0.56 and a y color coordinate from about 0.42 to about 0.48. The zinc sulfide phosphor is activated with manganese, copper, chlorine, and a metal selected from gold and antimony.
    Type: Grant
    Filed: September 5, 2002
    Date of Patent: January 27, 2004
    Assignee: Osram Sylvania Inc.
    Inventors: Xianzhong Chen, Robert L. Stevens, Judy A. Belinski-Wolfe, Fuqiang Huang, Chen Wen Fan, Michael A. Maxwell
  • Patent number: 6641756
    Abstract: A method for preparing a zinc sulfide phosphor having effective emission at low voltages. In the method for synthesizing a green-light emitting zinc sulfide based phosphor, ZnS:Cu, Al, which is applicable to a device operated with a low voltage, novel raw materials are employed. CuI is used as an activator, wherein monovalent copper (Cu1+) is complexed with ammonia and the ammonia complex is incorporated so as to uniformly distribute the activator in the mixture of raw materials. AlF3 is used as a co-activator, and, ZnI2 and NaI are added as iodide series fluxes. Thus, the color display characteristics are improved with a relatively high color purity and luminance.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: November 4, 2003
    Assignee: Samsung SDI Co., Ltd.
    Inventors: Soo-joung Lee, Jae-eun Jang
  • Patent number: 6610217
    Abstract: A ZnS:Ag,Al phosphor and method of making are described wherein the ZnS:Ag,Al phosphor exhibits a substantially polyhedral morphology and low particle agglomeration. The method of making includes the use of a mixed sodium chloride and alkaline-earth metal chloride flux. The resulting ZnS:Ag,Al phosphors may be made into finished CRT phosphors having improved CRT screen making properties.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: August 26, 2003
    Assignee: Osram Sylvania Inc.
    Inventors: Gregory A. Marking, Courtney S. Warren, Brian J. Payne
  • Patent number: 6444143
    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 a least one linking group for attachment of the compound to the overcoating layer and at least one hydrophilic group space 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 12Å to about 150Å, with a deviation of less than 10% in the core. The coated nanocrystal exhibits photoluminescende having quantum yield of greater than 10% in water.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: September 3, 2002
    Assignee: Massachusetts Institute of Technology
    Inventors: Moungi G. Bawendi, Frederick V. Mikulec, Jin-Kyu Lee
  • Patent number: 6395196
    Abstract: An electroluminescent phosphor with an extended half-life is created by means of the present invention by taking an amount of a phosphor and treating it with antimony comprising the steps of placing an amount of antimony in an inert reaction vessel, placing a vapor permeable filter on top of the antimony, placing a phosphor with a given half-life on top of the vapor permeable filter, evacuating the reaction vessel below one atmosphere and heating it for a period of time to allow the antimony to react with the phosphor to produce a new phosphor with an extended half-life.
    Type: Grant
    Filed: July 3, 2000
    Date of Patent: May 28, 2002
    Assignee: Osram Sylvania Inc.
    Inventors: Richard G. W. Gingerich, Clarence D. Vanderpool
  • Patent number: 6248261
    Abstract: An electroluminescent phosphor comprises zinc sulfide as a phosphor base material, at least one kind selected from copper and manganese as an activator, and at least one kind selected from chlorine, bromine, iodine, and aluminum as a coactivator. The content of alkaline earth metal elements in the electroluminescent phosphor is 0.05% by weight or less. In addition, the electroluminescent phosphor includes cesium in the range of 0.0001% by weight or more and 0.01% by weight or less. Such an electroluminescent phosphor has excellent brightness and life. An electroluminescent element comprises a phosphor layer in which an electroluminescent phosphor is dispersed in a dielectric. The electroluminescent phosphor includes reduced amount of alkaline earth metal elements and a slight amount of cesium.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: June 19, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Takemura, Yohe Shimizu, Takeshi Takahara, Mitsuhiro Oikawa
  • Patent number: 6214257
    Abstract: A method of increasing the brightness of an electroluminescent phosphor comprises the steps of forming the phosphor as a base phosphor to have a given brightness; and annealing the base phosphor at a temperature and for a time sufficient to increase the given brightness of the base phosphor and form an annealed phosphor. Brightness can be increased from 8% to about 33% when measure against a control made by the same process but not annealed.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: April 10, 2001
    Assignee: Osram Sylvania Inc.
    Inventor: Butchi Reddy Vaddi
  • Patent number: 6200496
    Abstract: A low-voltage excited white phosphor is provided. The white phosphor includes a ZnS:Zn phosphor and a (ZnnCd1−n)S:Ag,Cl phosphor (n=0.5 to 0.7), and has good color purity, high brightness and excellent color maintenance.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: March 13, 2001
    Assignee: Samsung Display Devices Co., Ltd.
    Inventors: Hyung-Keun Park, Sung-Kyoo Park