Luminophor for light sources
FIELD: physics, optics.
SUBSTANCE: invention relates to photoluminophors designed for converting emission of blue light-emitting diodes to the yellow-red region of the spectrum in order to obtain resultant white light, particularly to a cerium doped luminophor based on yttrium aluminium garnet used in two-component light-emitting diode light sources. The invention describes a luminophor for light sources which contain aluminium, yttrium, cerium, lutetium and oxygen in the following ratio: (Y1-xCex)3Al5O12 and 5-60 wt % over 100% (Lu1-yCey)2O3, where x=0.005-0.1; y=0.01-0.1. The invention provides a fine-grained luminophor with luminescent emission band maximum at λ≈590 nm, while lowering temperature and duration of synthesis.
EFFECT: use of such a luminophor in a two-component light source with a blue light-emitting diode enables to obtain resultant "warm" white light with high colour rendering index, increases uniformity of light scattering and reduces energy consumption during synthesis.
1 cl, 1 dwg, 6 ex
The invention relates to photoluminous serving to convert the blue light LEDs in the yellow-red region of the spectrum with the aim of obtaining the result of white light. In particular, legirovannom cerium the phosphor on the basis of yttrium-aluminum garnet used in two-component led light sources.
Known prepared by Sol-gel method, the phosphor composition (Lu1-xCex)3Al5O12where x=0,003-0,015 (H.-L.Li, X.-J.Liu, L.-P.Huang. "Luminescent properties of LuAG:Ce phosphors with different Ce contents prepared by a sol-gel combustion method". Optical Materials (2007), vol.29, p.1138-1142). The disadvantages of the known phosphor are relatively short position of luminescence band (the wavelength corresponding to its maximum, λmax≈505 nm) and a small half-width of this band (Δλ≈80 nm, Δν≈2900 cm-1). These shortcomings do not allow to get from the two-component light source comprising a blue led (λ≈450 nm) and well-known phosphor, the resulting "warm" white light.
Famous yellow phosphor composition (Gd1-xTbx)3(Ga1-yQy)2Al3Oz:aCe3+bB3+where Q is one or more elements selected from the group consisting of Si, Al and Sc; 0≤x≤0,1; 0<y<0,5; z=12 when y=0 or Q is one or more elements selected from the group of Si, Al and Sc, or 12+y where Q=Si; a=1-10 mol.% (Gd, Tb); the b=0.5 to 4 mol per 1 mol of the composition of the medium-host ("Yellow Phosphor and White Light Emitting Device Comprising it". WO 2007/018345 A1, 15.02.2007, IPC: C09K 11/80). The main disadvantage of this phosphor is relatively short position of luminescence band (λmax≈540 nm) and correspondingly low share of quanta emitted in the yellow-red region of the spectrum that does not allow you to get from the two light source result "warm" white light.
Famous yellow phosphor composition of Ca1-xAlSi4N7:Euxwhere to 0.001<x≤0,15 ("Yellow Light-Emitting Phosphor, White Light-Emitting Device Using the Same and Lighting Unit Using the Same", JP 2007169428, 05.07.2007, IPC: C09K 11/64; C09K 11/08; H01L 33/00; C09K 11/64; C09K 11/08; H01L 33/00). The main disadvantage of this phosphor is low half-band luminescence: Δλ≈80 nm, Δν≈2450 cm-1that is not possible to obtain from the two light source resulting white light with high color rendering index.
Closest to the claimed phosphor on the technical nature of a phosphor for light sources composition (Tb1-x-yRExCey)3(Al,Ga)5O12where RE=Y, Gd, La and/or Lu; 0≤x≤0,5-y; 0<y<0,1 ("Phosphor for Light Sources and Associated Light Source". US Patent 7063807 B2, 20.06.2006. IPC: H05B 33/14, 33/00). The disadvantages of the prototype are relatively short wavelength position of the maximum bandwidth of its luminescence (λmax≈550-575 nm), low value half-width of this band (λ≈117-129 nm) and high temperature is round and the duration of the synthesis (T=1450-1550°C and t=6 hours). These disadvantages limit the possibility of obtaining from the two light source resulting warm white light with high color rendering index, is the cause of high energy consumption of synthesis and not allow to obtain highly dispersed phosphor.
The task of the invention is the creation of highly dispersed phosphor with the position of the maximum of luminescence band at λ≈590 nm and decrease the temperature and duration of its synthesis. Using such a phosphor in a two-component source lighting with blue led will get the result "warm" white light with high color rendering index, to improve the uniformity of light scattering and reduce the energy of synthesis.
To solve this task, the phosphor for light sources containing aluminum, yttrium, cerium, lutetium and oxygen, contains these components in the following ratio: (Y1-xCex)3Al5O12and (5-60 wt.% in excess of 100%) (Lu1-yCey)2O3where x=0.005 to 0.1; y=0.01 and 0.1.
The proposed phosphor was prepared as follows.
Water 0.1m solutions of nitrate salts of yttrium and aluminum were mixed in accordance with the stoichiometry, was added a portion of Ce(NO3)3in necessary relation to the substituted ion Y3+and slowly laid siege MMA is ACOM with constant stirring to pH=7.5-8. The precipitate was washed with distilled water until pH 7.0 and were added in the form of an aqueous suspension of finely dispersed Lu2O3activated ions CE3+. The resulting mixture was stirred, the precipitate was separated by centrifugation, dried and thermoablative initially in air at T≈900°C for 2.5 hours, and then reducing conditions at T≈1000°C for 1 hour.
The use of colloid-chemical method of obtaining the proposed phosphor provides high uniformity and small size of the formed particles (the overwhelming proportion of these particles has a size of about 80 nm), which allows to significantly reduce the temperature and duration of heat treatment in comparison with the prototype.
The reduction in the proposed phosphor concentration (Lu1-yCey)2O3below the claimed does not provide a substantial increase in the spectrum of the luminescence share "red" quanta compared with (Y1-xCex)3Al5O12and the increase of this concentration in excess of the claimed leads to a significant decrease in the quantum yield of luminescence. The decrease in the concentration of Ce below the claimed impractical because of the low luminescence intensity, and its increase above declare that due to the weak luminescence in the concentration quenching.
The composition of the proposed phosphor, the width of luminescence band (Δλ) and wavelength (λmax)corresponding to the maximum of this band is shown in the table.
|1||(Yof 0.95Ce0,05)3Al5O12+(5 wt.% in excess of 100%) (Luof 0.95Ce0,05)2About3||135||583|
|2||(Yof 0.95Ce0,05)3Al5O12+(10 wt.% in excess of 100%) (Luof 0.95Ce0,05)2About3||140||590|
|3||(Yof 0.95Ce0,05)3Al5O12+(50 wt.% in excess of 100%) (Luof 0.95Ce0,05)2About3||140||590|
|4||(Y0,995Ce0,005)3Al5O12+(50 wt.% in excess of 100%) (Lu0,99Ce0,01)2About3||140||590|
|5||(Yfor 0.9Cea 0.1)3Al5O12+(60 wt.% in excess of 100%) (Lufor 0.9Cea 0.1)2About3||143||593|
The drawing shows normalized to the maximum intensity of the "quantum" time-resolved emission spectra (curve 1) and its excitation (curve 2) sample 3.
It is seen that the proposed phosphor compared to the prototype has a wider band luminescence and more far-position of its maximum. In addition, the size of its grains is approximately 80 nm, and the synthesis is carried out at considerably lower temperatures of heat treatment and with less duration of the last.
These advantages offered by the phosphor when used in a two-component source lighting with blue led will get the result "warm" white light with a higher color rendering index and to improve the uniformity of light scattering. The small grain size of the phosphor reduces the energy of synthesis, and during pressing to get more dense layers. In addition, the use of the phosphor in the thin-layer screen coatings will significantly increase their authorised the total capacity.
The phosphor for light sources containing aluminum, yttrium, cerium, lutetium and oxygen, characterized in that it contains these components in the following ratio:
5-60 wt.% in excess of 100% (Lu1-yCey)2O3,
where x=0,005-0,1; y=0.01 and 0.1.
SUBSTANCE: invention refers to electroluminescent system. Electroluminescent system includes electroluminescent device (1) which contains the first junction electrode (2) made from transparent material. For each of big surfaces of this first electrode (2) there provided is one layer (3, 4) of dielectric material having luminescent properties. These luminous layers are transparent and are made from materials capable of emitting the light with various wave lengths. One electrode (5, 6) is provided on big surfaces of luminous layers (3, 4), which are located on opposite side from common electrode (2). System includes power supply device which serves as control device of luminous layers, which contains two voltage sources. Luminous layers are made from materials capable of emitting the light with various wave lengths. Control device is made so that strips of electrodes can be connected to power supply separately. For rear side of electroluminescent device there provided is layer with mirror coating; mirror surface of this layer faces luminous layers of electroluminescent device.
EFFECT: proposed screens are non-sensitive to touch, and deep drawing thereof is allowed.
10 cl, 5 dwg
SUBSTANCE: electroluminescent material is described, consisting of an electron injection layer, an active luminescent layer based on a metal chalate complex, a hole transport layer and a hole injection layer. The luminescent substance is in form of new zinc complexes based on sulphonylamino derivatives of 2-phenylbenzoxazole or 2-phenylbenzothiazole. The hole transport layer of the material is preferably a mixture of triphenylamine oligomers.
EFFECT: electroluminescent material with high moisture resistance, high resistance to crystallisation and high thermal stability.
9 cl, 5 ex
FIELD: polymer materials.
SUBSTANCE: invention provides luminescent material showing semiconductor properties and being product of complex polymerization in glow discharge, which is formed as a supported polymer layer located either between electrodes or on any of electrodes. Starting pyrromethene complex is difluoroborate complex of 1,3,5,7,8-pentamethyl-2,6-diethylpyrromethene (Pyrromethene 567). Method of preparing luminescent semiconductor polymer material comprises glow-discharge polymerization for 2 to 120 min of Pyrromethene 567 vapors at temperature preferably 250-350°C, pressure 10-1 to 10-2 Pa, and discharge power 0.5-3 W. Resulting luminescent polymer is characterized by thickness preferably 0.001-10 μm, conductivity 1·10-10 to 5·10-10 Ohm-1cm-1 (20°C), luminescence emission maximum in the region of 540-585 nm at band halfwidth 55-75 nm. Polymer is obtained with quantum yield 0.6-0.8 and is designed for creation of film light-emitting devices.
EFFECT: improved performance characteristics of material.
13 cl, 3 ex
FIELD: microelectronics; production of light-emitting diodes.
SUBSTANCE: the invention is pertinent to microelectronics and may be used in production of light-emitting diodes. Electroluminescent polymeric nanocomposite material contains 50-99.5 mass % of polymer - water-soluble polyphenylamine with electron-hole conductance, and 50-0.5 mass % of an electroluminescing organic ingredient in the form of J- component units - a cyanine dye, a squaryl dye or a porphyrin. For production of the electroluminescent material first solve polyphenylamine in water, then introduce a powder of the indicated dye. Formation of J- component units fix according to a change of the solution color. Produced nanocomposite material is applied on the current-conducting substrate, dried. Then apply a layer of a metal-cathode. The invention allows to produce electroluminescent layers with a band of electroluminescence from 400 up to 1600 nm having high characteristics, for instance, luminance and efficiency.
EFFECT: the invention ensures production of electroluminescent layers with a band of electroluminescence from 400 up to 1600 nm having high luminance and efficiency.
FIELD: fire safety.
SUBSTANCE: luminescent composition for hidden marking, exposed when radiated with visible, infrared or ultraviolet radiation, contains binary mix, which includes luminophore with long afterglow on the basis of strontium aluminate, which is activated with europium, dysprosium and yttrium - LDP-1-3M, and photoluminophore with yellow, blue, red or white glow colour. Luminophores are taken with the mass ratio of 70:30. For even glow field, size of luminophore particles is selected in the range of 1-25 mcm, and flow glow of "Star sky" type - in the range of 20-180 mcm. Fire-prevention fireproofing composition includes fire-prevention composition and luminescent additive - specified binary mix. Method for marking of fire-prevention compositions consists in preparation of specified binary mixture, its introduction in amount of 0.01-35 wt parts per 100 wt parts of polymer binder. Produced marking is applied manually, by explication and printing methods in the form of information or graphic symbols, signs, text.
EFFECT: afterglow brightness and duration increase, as well as fire resistance, temperature range of afterglow expands, as a result, fast and reliable detection of fire-prevention composition is provided, as well as visualisation of extinguishing site.
3 cl, 4 tbl
SUBSTANCE: invention can be used for making dyes, plastics, resins, glass and ceramic objects, cements, adhesives, fibres, yarn. Aluminate luminophores, which are a matrix based on aluminium oxide and oxides of at least one element chosen from: Mg, Ca, Sr, Ba, Zn, Si, activated by at least one rare-earth element, are treated with aqueous solutions of monosubstituted phosphates at pH 6 at the beginning and pH above 7 at the end of treatment or solutions of agents chosen from: H2SO4, H3PO4, monosubstituted phosphates, mixture of tri- or disubstituted phosphates with at least one acid from: HCl, H2SO4 or HNO3 at pH 1 at the beginning and pH not above 4 a the end of treatment. The oxide matrix can have formula: MO-SiO2-Al2O3: R, MAl2O4:R, -MAlO4:R, Sr4Al14O25: R, where M - is a metal, chosen from: Ca, Mg, Sr, Ba, Zn; R - at least one rare-earth metal, chosen from a group consisting of Dy, Nd, Eu, Tm, Tb, Y,Yb.
EFFECT: invention increases luminous intensity of aluminate luminophores without reducing hydrolytic stability.
5 cl, 3 tbl, 27 ex
SUBSTANCE: water-resistant fluorescent pigment is an oxide matrix based on aluminium oxide and, at least, one of the following elements: Mg, Са, Sr, Ва, Zn, Mn, Si, В, Р, Ga, activated with, at least, single rare earth element, treated with a mixture of salts from the following group: Na3PO4, Na2HPO4, (NH4)2HPO4, Ca3(PO4)2, with acids from the following group: HCl, H2SO4, HNO3, pH not exceeding 4 at the end of treatment. Oxide matrix may be of formula MO-SiO2Al2O3:R, where М stands for, at least, a single metal from the following group: Ca, Sr, Ba, Mg, Zn; R stands for, at least, a single element from the following group: Dy, Nd, Eu, Tm, Tb, Y, Yb; MAl2O4:R, where М stands for, at least, a single metal from the following: Ca, Sr, Mg, Ba, while R stands for, at least, a single element from the following: Dy, Nd, Eu, Tm, Tb, Y, Yb; MAlO4:R, where М stands for, at least, a single metal from the following: Sr, Ca, Ba; R stands for, at least, a single element from the following group: Dy, Nd, Eu, Tm, Tb, Y, Yb. Ink contains the said fluorescent pigment and thickening agent.
EFFECT: water-resistant at room or elevated temperature, fluorescent properties being retained.
5 cl, 5 tbl, 57 ex
FIELD: polymer materials.
SUBSTANCE: polymeric layer is made in the form of polydimethylsiloxane or polycarbonate-based film uniformly filled with luminophor mixture in amount 10 to 80%, which mixture contains ZnS·Co·Ni and/or ZnS·CsS·Cu·Co Ni and CeAl2O4·Eu·Dy. Weight ratio of zinc sulfide to aluminate luminophor ranges from 1:99 to 10:90. Molecular weights of polydimethylsiloxane and polycarbonate are more than 30000 and 30000-35000, respectively. Luminophor particle size is 10 to 60 mcm. Thickness of polymer film is ranges from 90 to 2000 mcm. In case of polycarbonate polymeric film, informational graphic symbols, marks, and text are applied onto surface of the film by offset print technique and, in case of polydimethylsiloxane film, by explication technique. Polymeric layer may be supported by light-reflecting carrier whose thickness id comparable with that of luminophor grains. Initial brightness and accumulated light are in excess as compared to prior art analogues.
EFFECT: increased strength, elasticity, resistance to mechanical and environmental effects, reduced cost, and prolonged after-excitation emission.
6 cl, 3 tbl
SUBSTANCE: invention is meant for the chemical industry and can be used to protect bond paper and valuable documents, strict accounting forms, conformity marks of articles, excise and certification marks. An infrared luminophor having formula Y2-x-yErxCeyO2S, where x=0.20-0.45; 1·10-4≤y≤5·10-3 is described.
EFFECT: obtaining an infrared luminophor based on yttrium oxysulphide activated by erbium ions and co-activated by cerium ions, which has minimal visible anti-stokes luminescence when excited with laser radiation in the 0,90-0,98 mcm range and high intensity of stokes infrared luminescence in the 1,5-1,5 mcm range.
1 cl, 1 tbl, 12 ex
FIELD: printing industry.
SUBSTANCE: valuable document has marking, which contains luminescent compound that has both anti-stokes and Stocks law luminescence, with composition of Ln 1-X-Y-Z YbX ErY CeZ MeI C MeVI D PI-D O4+D/2-C where: MeI - Li or Na, MeVI - W or Mo, Ln - Y, La, Gd, 0.1 ≤ x ≤ 0.9; 0.005 ≤ y ≤ 0.2; 0.0001 ≤ z ≤ 0.01; 0.001 ≤ c ≤ 0.1; 0.001 ≤ d ≤ 0.1; or compound of the following composition: Ln 2-X-Y-Z YbX ErY CeZ O2 S, where Ln - Y, La, Gd, 0 <x ≤ 0.2; 0.1 ≤ y ≤ 0.4; 0.0001 ≤ z ≤ 0.005; or compound of the following composition: Ln 2-X-Y-Z ErY CeZ O2 S; where Ln - Y, La, Gd, 0 < x ≤ 0.2; 0.1 ≤ y ≤ 0.4; 0.0001 ≤ z ≤ 0.005. Marking may be made by printing method, for instance offset method of printing. Method for identification of valuable document authenticity with all above mentioned criteria inherent in it includes detection of hidden protective marking on a valuable document by measurement and further analysis of dependency extent of stokes and anti-stokes luminescence strip intensity on density of excitation radiation capacity.
EFFECT: improved level of valuable document protection.
SUBSTANCE: invention relates to liquid crystal materials and can be used as flawless luminescent optical media in electro-optical and magneto-optical devices. A lyotropic liquid crystal composition is described, which contains oxyethylated surface active substance in form of 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis[29-hydroxy(3,6,9,12,15,18,21,24,27-oxanonacosaneoxy]-pentacyclo[19.3.-1.13,7.19,13.115,19]octacosa-1(25)3,5,7(28)9,11,13(27)15,17,19(26)21,13-dodecane, hexahydrate of europium nitrate and solvent in form of ethanol. Components of the composition are in the following ratio, wt %: said oxyethylated surface active substance - 55 to 79, hexahydrate of europium nitrate - 12 to 35, ethanol - 5 to 33.
EFFECT: production of lyotropic liquid crystal composition, with twelve times more luminescence efficiency and double the mean life of luminescent glow.
1 cl, 5 dwg, 1 tbl, 4 ex
FIELD: materials useful in agriculture, medicine, biotechnology, light industry.
SUBSTANCE: claimed material includes matrix and at least one light-converting compound, namely luminophor converting UV radiation into radiation of other colors and has particle size from 0.3 to 0.8 mum and general formula of Mex aAy bRz c, wherein Me is yttrium, lanthanum, cerium, praseodium, europium, gadolinium, dysprosium, erbium, ytterbium, aluminum, bismuth, manganese, calcium, strontium, barium, zinc, cesium; A is cerium, praseodium, europium, gadolinium, dysprosium, erbium, ytterbium, aluminum, indium and/or combination thereof; R is oxygen, sulfur, phosphorus, boron, vanadium, titanium, aluminum, indium and/or combination thereof; a, b and c represent charge of Me, A or R ions, respectively; x >=1; 1.0>=y>=0.0001; z corresponds ax+by=cz. Aldo disclosed is composition for material production containing abovementioned light-converting compound in amount of 0.001-10.0; and balance - matrix-forming component, e.g. polymer, fiber, varnish- or adhesive-forming agent.
EFFECT: conversion of UV irradiation of increased effectiveness; increased plant productivity.
16 cl, 21 ex