WO2017170609A1 - 蛍光体、発光装置、照明装置及び画像表示装置 - Google Patents
蛍光体、発光装置、照明装置及び画像表示装置 Download PDFInfo
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- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
- C09K11/7766—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
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- C09K11/7766—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
- C09K11/77747—Silicon Nitrides or Silicon Oxynitrides
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- C09K11/0883—Arsenides; Nitrides; Phosphides
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- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/48—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
- H01L33/50—Wavelength conversion elements
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- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/48—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
- H01L33/50—Wavelength conversion elements
- H01L33/501—Wavelength conversion elements characterised by the materials, e.g. binder
- H01L33/502—Wavelength conversion materials
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/48—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
- H01L33/50—Wavelength conversion elements
- H01L33/501—Wavelength conversion elements characterised by the materials, e.g. binder
- H01L33/502—Wavelength conversion materials
- H01L33/504—Elements with two or more wavelength conversion materials
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- H—ELECTRICITY
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- H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
- H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
- H01L25/075—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00
- H01L25/0753—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00 the devices being arranged next to each other
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/48—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
- H01L33/50—Wavelength conversion elements
- H01L33/505—Wavelength conversion elements characterised by the shape, e.g. plate or foil
Definitions
- the present invention relates to a phosphor, a light emitting device, a lighting device, and an image display device.
- the LED used here is a white light emitting LED in which a phosphor is disposed on an LED chip that emits light of blue or near ultraviolet wavelength.
- a LED using a YAG (yttrium, aluminum, garnet) phosphor that emits yellow light using blue light from a blue LED chip as excitation light on a blue LED chip is often used. Yes.
- the emission color of the YAG phosphor in order to set the emission color of the YAG phosphor to 550 nm or more, it is necessary to adjust the matrix constituent elements by adding gadolinium or terbium, and the temperature characteristics may be remarkably lowered.
- near ultraviolet light when excited with near ultraviolet light (usually, a range including violet of about 350 to 420 nm as a term for blue excitation is referred to as near ultraviolet light), the luminance is remarkably high. There was a case of decline.
- nitride phosphors that emit yellow light.
- the phosphor for example, (La, Y) 3 Si 6 N 11 phosphor described in Patent Documents 1 to 3 (including the case where lanthanum or yttrium is replaced with another metal, etc.) are sometimes referred to as “LYSN phosphors”).
- the LED is widely known as a semiconductor light emitting device or a semiconductor light source capable of generating light having a peak wavelength in a specific region of the light spectrum. LEDs are usually used as light sources for illuminators, signs, vehicle headlamps and displays.
- a light-emitting device that emits white light in combination with an LED chip that emits blue light and a YAG (yttrium, aluminum, garnet) phosphor that converts blue light into yellow is known. It has been.
- the YAG phosphor is disposed around the LED chip as a wavelength conversion light emitting layer dispersed in an epoxy resin or a silicone resin.
- a ceramic layer made of a phosphor or a wavelength-converted light-emitting layer (light-emitting ceramic layer) made only of an inorganic material in which the phosphor is dispersed in ceramic is exemplified.
- These phosphor materials are known to exhibit yellow or red light emission when excited by a blue LED or near-ultraviolet LED, and have higher luminance and higher conversion efficiency than oxide-based phosphors. Furthermore, the temperature dependence of the luminous efficiency is excellent.
- a wavelength conversion light emitting layer dispersed in an organic binder such as an epoxy resin or a silicone resin has insufficient durability, heat resistance, and light emission intensity. Therefore, in order to obtain a wavelength-converting light-emitting layer with better durability and heat resistance, a method for producing a wavelength-converted light-emitting layer (light-emitting ceramic layer) made only of an inorganic material as illustrated in Patent Document 4 is studied. Has been.
- YAG Ce phosphor particles are contained in an inorganic binder made of any one of calcium fluoride, strontium fluoride, and lanthanum fluoride, or made of calcium fluoride and strontium fluoride. Dispersed phosphor ceramics are illustrated.
- Patent Document 6 Y 3 (Al, Ga) 5 O 12 : Ce oxide phosphor, Lu 3 Al 5 O 12 : Ce (LuAG) oxide phosphor and CaSiAlN 3 : Eu (CASN) nitride phosphor are used.
- the combination is used to melt a glass powder having a glass transition point of 200 ° C. or higher by using a discharge plasma sintering method, thereby producing a wavelength conversion light emitting layer made of only an inorganic material.
- the LYSN phosphors described in Patent Documents 1 to 3 have a small decrease in light emission luminance even when the temperature rises, and sufficient light emission can be obtained even when excited by near ultraviolet rays.
- a lighting device is manufactured using a LYSN phosphor, it is necessary to use a red phosphor to compensate for the red color. Therefore, the LYSN phosphor having an emission peak in a longer wavelength region (546 to 570 nm). Is required. These phosphors are required to have higher emission luminance and temperature maintenance rate.
- an aluminum garnet phosphor is used as the luminescent ceramic layer. This was obtained by producing a YAG powder from Y 2 O 3 , Al 2 O 3 (99.999%) and CeO 2 , obtaining a molded body consisting only of YAG powder, and firing at 1300 ° C. YAG sintered phosphor is used as the luminescent ceramic layer.
- the luminescent ceramic layer does not use an inorganic binder and forms a sintered body only with a YAG oxide phosphor. Therefore, there has been a demand for sintered phosphors of nitride phosphors that have high luminance, high conversion efficiency, and excellent temperature dependence of luminous efficiency.
- the ceramic composite of the YAG oxide phosphor phase and the fluoride matrix phase has a problem that the internal quantum efficiency is a low value of 55% or less.
- a wavelength conversion light-emitting layer is manufactured by dispersing a YAG oxide phosphor or a combination of a LuAG oxide phosphor and a CASN nitride phosphor in glass by melting glass powder. Since the inorganic binder is glass, it has heat resistance, but its thermal conductivity is as low as 2 to 3 W / mK, and its heat dissipation is low, so the temperature of the phosphor rises and the brightness decreases (deterioration of the phosphor) ).
- the present invention provides a LYSN phosphor having an emission peak in a long wavelength region (546 to 570 nm) (hereinafter sometimes referred to as “long wavelength LYSN phosphor”). Furthermore, the present invention provides a LYSN phosphor having high emission luminance and high temperature maintenance rate. The present invention also provides a high-quality light-emitting device with a low color temperature and a high-quality lighting device and image display device without using a red phosphor.
- the present invention also provides a sintered phosphor for LED having high internal quantum efficiency and high transmittance in view of the above problems.
- a sintered phosphor capable of obtaining light emission with a low color temperature is provided.
- the light emission efficiency is high, the brightness is high, the brightness change and the color shift due to the change of the excitation light intensity and the temperature are small, and the light of the low color temperature with a lot of red component is emitted.
- a light-emitting device that emits light
- an illumination device and a vehicular lamp / indicator using the light-emitting device are provided.
- a LYSN phosphor having an emission peak wavelength on the long wavelength side and a high emission luminance has a smaller crystal lattice size than a conventional LYSN phosphor. .
- a long-wavelength LYSN phosphor having high emission luminance can be defined by a lattice constant, which is one of the indices of the size of the crystal lattice, and a ratio of specific constituent elements. Reached.
- a phosphor containing a tetragonal crystal phase contains M element, La, A element, Si, N and satisfies the following formulas [I] and [II];
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element.
- w represents the content of La element when the molar ratio of Si is 6
- x represents the content of element A when the molar ratio of Si is 6
- z represents the content of M element when the molar ratio of Si is 6.
- a phosphor containing a tetragonal crystal phase, wherein the crystal phase contains an M element, La, A element, Si, N, and a lattice constant a is 10.104 ⁇ or more and 10.154 ⁇ or less.
- a phosphor obtained by preparing and firing a raw material so that the ratio of each element contained in the raw material satisfies the following formulas [III] and [IV].
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element.
- w2 represents the charged amount of La element when the molar ratio of Si is 6
- x2 represents the charged amount of the element A when the molar ratio of Si is 6.
- the phosphor according to 1 or 2 above, wherein the crystal phase has a composition represented by the following formula (1).
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element
- w, x, y, and z are values satisfying the following formulas independently.
- w is 1.50 ⁇ w ⁇ 2.7.
- x is 0.2 ⁇ x ⁇ 1.5
- y is 8.0 ⁇ y ⁇ 14.0
- z is 0.05 ⁇ z ⁇ 1.0
- a lighting device comprising the light-emitting device according to 5 as a light source. 7).
- An image display device comprising the light-emitting device according to 5 as a light source. 8).
- a method for producing a phosphor, wherein the crystal phase includes M element, La, A element, Si, N, and the lattice constant a is 10.104 to 10.54.
- a method for producing a phosphor characterized in that an M source, an La source, an A source, and an Si source are used as raw materials, and the raw materials are prepared and fired so that the ratio of each element satisfies the following formulas [III] and [IV]: . 0.1 ⁇ x2 / (w2 + x2) ⁇ 0.5 [III] 2.85 ⁇ w2 ⁇ 3.2 [IV] (However, M element represents one or more elements selected from activators, The A element represents one or more elements selected from rare earth elements other than La and an activating element.
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element
- w2 is a value satisfying the formula [IV]
- x2, y2, and z2 are values that satisfy the following formulas independently.
- x2 is 0.2 ⁇ x2 ⁇ 1.5.
- y2 is 8.0 ⁇ y2 ⁇ 14.0
- z2 is 0.05 ⁇ z2 ⁇ 1.0
- the present invention can provide a LYSN phosphor having an emission peak in a long wavelength region (546 to 570 nm). Furthermore, the present invention can provide a LYSN phosphor having high emission luminance and high temperature maintenance rate. In addition, the present invention can provide a high-quality light emitting device with high color rendering and a high-quality lighting device and image display device without using a red phosphor.
- FIG. 1 is a diagram showing emission spectra of the phosphors obtained in Example 8 and Comparative Example 1.
- FIG. 2 is a diagram showing XRD patterns of Example 5 and Comparative Examples 4 and 5.
- FIG. 3 is a schematic diagram illustrating a configuration example of a semiconductor light emitting device according to an embodiment of the present invention.
- FIG. 4 is a schematic diagram showing a configuration example of a semiconductor light emitting device according to an embodiment of the present invention.
- FIG. 5 is a graph showing a powder X-ray diffraction pattern of the phosphor used in Example 15.
- 6 is a view showing a powder X-ray diffraction pattern of the phosphor used in Example 16.
- FIG. 7 is a diagram showing emission spectra of the sintered phosphors of Example 15 and Example 16 by LED excitation.
- FIG. 8 is a diagram illustrating a simulation result of an emission spectrum of the sintered phosphor of Example 17 by LED excitation.
- FIG. 9 is a diagram illustrating a simulation result of an emission spectrum of the sintered phosphor of Example 18 by LED excitation.
- FIG. 10 is a diagram showing a simulation result of an emission spectrum of the sintered phosphors of Examples 19 to 22 by LED excitation.
- FIG. 11 is a diagram showing simulation results of emission spectra of the sintered phosphors of Examples 23 to 26 by LED excitation.
- FIG. 12 is a diagram showing an emission spectrum of the sintered phosphors of Examples 27 and 28 by LED excitation.
- each composition formula is delimited by a punctuation mark (,).
- commas when a plurality of elements are listed separated by commas (,), one or two or more of the listed elements may be included in any combination and composition.
- invention 1 embodiments of the phosphor, the light emitting device, the illumination device, and the image display device of the present invention will be described in detail.
- the present invention is not limited to the following embodiments and is within the scope of the gist thereof. It can be implemented with various modifications.
- the following phosphors, light-emitting devices, illumination devices, and image display devices of the present invention may be referred to as “invention 1”.
- the phosphor of the present invention includes a tetragonal crystal phase,
- the crystalline phase contains M element, La, A element, Si, N and satisfies the following formulas [I] and [II];
- the lattice constant a is from 10.104 to 10.54.
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element.
- w represents the content of La element when the molar ratio of Si is 6
- x represents the content of element A when the molar ratio of Si is 6
- z represents the content of M element when the molar ratio of Si is 6.
- content of each element when the molar ratio of Si is set to 6 is shown by molar ratio.
- the phosphor of the present invention can be obtained by preparing and firing a raw material so that the ratio of each element contained in the raw material satisfies the following formulas [III] and [IV].
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element.
- w2 represents the charged amount of La element when the molar ratio of Si is 6
- x2 represents the charged amount of the element A when the molar ratio of Si is 6.
- the charged amount of each element when the Si molar ratio is set to 6, that is, the composition of the metal element contained in the raw material is indicated by the molar ratio.
- M element represents one or more elements selected from activators.
- the activation element include europium (Eu), cerium (Ce), manganese (Mn), iron (Fe), praseodymium (Pr), and the like.
- the M element one kind of element may be used alone, or two or more different kinds of elements may be included.
- the M element preferably contains Eu or Ce, more preferably contains 80 mol% or more of Ce in all the activation elements, and further preferably contains 95 mol% or more of Ce in all the activation elements, Ce It is most preferable to contain alone.
- La represents lanthanum.
- a element represents one or more elements selected from rare earth elements other than La and an activating element.
- the element A include yttrium (Y), gadolinium (Gd), neodymium (Nd), samarium (Sm), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), and thulium (Tm). ), Lutetium (Lu), ytterbium (Yb), and the like.
- the element A preferably contains Y in that the effect of the present invention is easily obtained.
- one type of element may be used alone, or two or more different types of elements may be included.
- Si represents silicon. Si may be partially substituted with other tetravalent elements such as germanium (Ge), tin (Sn), titanium (Ti), zirconium (Zr), hafnium (Hf), and the like.
- N represents a nitrogen element. N may be partially substituted with other elements such as oxygen atoms (O), halogen atoms (fluorine (F), chlorine (Cl), bromine (Br), iodine (I), etc.).
- Oxygen may be mixed as an impurity in the raw metal, or may be introduced during a manufacturing process such as a pulverization process or a nitriding process, and is inevitably mixed in the phosphor of the present invention.
- halogen atoms may be mixed as impurities in the raw material metal or introduced during the manufacturing process such as a pulverization process or nitriding process.
- halogen atoms are contained in the phosphor. May be included.
- the phosphor of the present invention satisfies the formulas [I] and [II].
- X / (w + x) in the formula [I] is preferably 0.11 or more and 0.45 or less, and more preferably 0.12 or more and 0.40 or less, when the molar ratio of Si is 6.
- w + x + z in the formula [II] is preferably 2.85 or more and 3.15 or less, more preferably 2.90 or more and 3.10 or less, when the molar ratio of Si is 6.
- the emission peak wavelength of the phosphor is on the long wavelength side. Therefore, it is preferable to combine the phosphor of the present invention with the blue LED chip alone because a color temperature of about 3000 to 5000K can be achieved. Moreover, it is preferable at the point which becomes difficult to produce
- the phosphor of the present invention can be obtained by preparing and firing the raw material so that the ratio of each element contained in the raw material satisfies the above formulas [III] and [IV].
- X2 / (w2 + x2) in the formula [III] is a value satisfying 0.1 ⁇ x2 / (w2 + x2) ⁇ 0.5 when the Si molar ratio is 6, and the lower limit is preferably 0. 105, more preferably 0.11, and the upper limit is preferably 0.4, more preferably 0.3.
- w2 is a value satisfying 2.85 ⁇ w2 ⁇ 3.2 when the molar ratio of Si is 6, and the lower limit thereof is preferably 2.875, and the upper limit thereof. Is preferably 3.15.
- the phosphor of the present invention preferably includes a crystal phase having a composition represented by the following formula (1).
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element
- w, x, y, and z are values satisfying the following formulas independently.
- w is 1.50 ⁇ w ⁇ 2.7.
- x is 0.2 ⁇ x ⁇ 1.5
- y is 8.0 ⁇ y ⁇ 14.0
- z is 0.05 ⁇ z ⁇ 1.0
- the M element and the A element in the formula (1) are in the same range as the elements described above, and the ranges and preferred embodiments are also the same.
- W in Formula (1) represents the content of La and has the same meaning as in Formulas [I] and [II]. The range and preferred embodiments are also the same.
- X in the formula (1) is synonymous with that in the formulas [I] and [II] and represents the content of the element A, and the range is usually 0.2 ⁇ x ⁇ 1.5, and the lower limit is , Preferably 0.25, more preferably 0.30, and the upper limit is preferably 1.2, more preferably 1.0.
- y represents the content of N, and the range is usually 8.0 ⁇ y ⁇ 14.0, and the lower limit is preferably 8.5, more preferably 8.0, The upper limit is preferably 13.5, more preferably 13.0.
- Z in Formula (1) represents the content of M element, and the range thereof is usually 0.05 ⁇ z ⁇ 1.00, and the lower limit is preferably 0.10, more preferably 0.20, The upper limit is preferably 0.95, more preferably 0.90.
- content of each above-mentioned element is shown by molar ratio.
- the phosphor of the present invention has a tetragonal crystal structure reported by the composition formula of La 3 Si 6 N 11 , and La, A element, and M element are inserted at the position of La in the composition formula. Such element substitution results in crystals having different lattice constants and atomic coordinates while maintaining the basic skeleton structure.
- the space group in the phosphor of the present invention is not particularly limited as long as the average structure statistically considered within a range that can be distinguished by single-crystal X-ray diffraction shows a repetition period of the above length, but “International Tables” It belongs to P4bm (100) based on “For Crystallography (Third, Revised edition), Volume A SPACE-GROUP SYMMETRY”.
- La 3 Si 6 N 11 is a tetragonal crystal having a P4bm space group, and its a-axis lattice constant (lattice constant a) is 10.1988 ⁇ , c-axis Has a lattice constant (lattice constant c) of 4.84153.
- the phosphor of the present invention is based on La 3 Si 6 N 11 and has Y, Gd, etc. having an ionic radius smaller than La substituted for La.
- the lattice constant in the phosphor of the present invention is as follows.
- the a-axis lattice constant (lattice constant a) is a value satisfying 10.104 ⁇ or more and 10.154 ⁇ or less, and the lower limit thereof is preferably 10.109 ⁇ , more preferably 10.114 ⁇ , and the upper limit thereof.
- the value is preferably 10.149 ⁇ , more preferably 10.144 ⁇ .
- the b-axis lattice constant (lattice constant b) is the same value as the lattice constant a.
- the c-axis lattice constant (lattice constant c) is a value that usually satisfies 4.820 ⁇ or more and 4.860 ⁇ or less, and its lower limit is preferably 4.825 ⁇ , more preferably 4.830 ⁇ ,
- the upper limit value is preferably 4.865cm, more preferably 4.860mm.
- the lattice constant a is in the above range in that the effect of the present invention can be obtained satisfactorily. Furthermore, it is preferable that the lattice constant c is in the above range in that the effect of the present invention can be easily obtained.
- Such a phosphor is excellent in crystallinity because crystals are stably generated and generation of an impurity phase is suppressed. For this reason, the phosphor of the present invention is preferable because the emission luminance is good.
- the A element in the present invention is an element having an ion radius smaller than that of La. Therefore, when La is partially substituted with a specific amount of A element, the distance between ions in the crystal lattice is shortened. That is, the lattice constant of the phosphor is reduced. As a result, the crystal field around the activating element becomes strong, and the emission peak wavelength of the phosphor becomes longer.
- the lattice constant and the space group can be obtained according to a conventional method.
- the lattice constant can be obtained by X-ray diffraction and / or neutron diffraction results obtained by Rietveld analysis, and the space group can be obtained by electron diffraction.
- the luminescent color of the phosphor of the present invention is excited by light in the near ultraviolet region to blue region having a wavelength of 300 nm to 460 nm by adjusting the chemical composition and the like, and is bluish green, green, yellowish green, yellow, orange, red, etc. , A desired emission color can be obtained.
- the phosphor of the present invention preferably has the following characteristics when an emission spectrum is measured when excited with light having a wavelength of 300 nm or more and 460 nm or less.
- the phosphor of the present invention has a peak wavelength in the above-mentioned emission spectrum of usually 546 nm or more, preferably 550 nm or more, and usually 570 nm or less, preferably 565 nm or less.
- the obtained phosphor is preferable in that it exhibits a good green or yellow color.
- the half width of the emission peak in the above-mentioned emission spectrum is usually 130 nm or less, preferably 125 nm or less, more preferably 120 nm or less, and usually 30 nm or more, preferably 40 nm or more, more preferably 60 nm or more. is there.
- a xenon lamp in order to excite the phosphor of the present invention with light having a wavelength of 300 nm or more and 460 nm or less, for example, a xenon lamp can be used.
- a GaN-based LED can be used for excitation with 400 nm light.
- the emission spectrum of the phosphor of the present invention is measured using a 150 W xenon lamp as an excitation light source and MCPD7000 (manufactured by Otsuka Electronics Co., Ltd.) as a spectrum measuring device.
- An emission spectrum is obtained by measuring the emission intensity of each wavelength with a spectrum measuring device in the wavelength range of 380 nm to 800 nm under the condition of excitation light of 455 nm.
- the phosphor of the present invention has an excitation peak in a wavelength range of usually 350 nm or more, preferably 360 nm or more, more preferably 370 nm or more, and usually 480 nm or less, preferably 470 nm or less, more preferably 460 nm or less. That is, it is excited by light in the near ultraviolet to blue region.
- the method for producing the phosphor of the present invention is not particularly limited as long as the phosphor of the present invention and the effect can be obtained.
- raw materials are prepared so as to satisfy the above formulas [III] and [IV].
- the method of baking is mentioned, Preferably, the method of adjusting preparation amount so that the crystal phase of fluorescent substance may satisfy
- M element represents one or more elements selected from activators
- the A element represents one or more elements selected from rare earth elements other than La and an activating element
- w2 is a value satisfying the formula [IV]
- x2, y2, and z2 are values that satisfy the following formulas independently.
- x2 is 0.2 ⁇ x2 ⁇ 1.5.
- y2 is 8.0 ⁇ y2 ⁇ 14.0
- z2 is 0.05 ⁇ z2 ⁇ 1.0
- W2 in Formula (2) represents the content of La and has the same meaning as in Formula [IV].
- the range and preferred embodiments are also the same.
- X2 in the formula (2) is synonymous with that in the formula [III] and represents the content of the element A.
- the range is usually 0.2 ⁇ x2 ⁇ 1.5, and the lower limit is preferably 0. .25, more preferably 0.30, and the upper limit is preferably 1.2, more preferably 1.0.
- Y2 in Formula (2) represents the content of N, and the range is usually 8.0 ⁇ y2 ⁇ 14.0, and the lower limit is preferably 8.5, more preferably 9.0, The upper limit is preferably 13.5, more preferably 13.0.
- Z2 in Formula (2) represents the content of the M element, and the range is usually 0.05 ⁇ z2 ⁇ 1.00, and the lower limit is preferably 0.10, more preferably 0.20, The upper limit is preferably 0.95, more preferably 0.90.
- content of each above-mentioned element is shown by molar ratio.
- the production method of the phosphor of the present invention is more specifically, for example, Although there is a method of charging in this way without excess or deficiency and charging elements La and A so as to satisfy the formulas [III] and [IV], the present invention is not limited to these.
- La source, A source, Si source, M source used in the present invention, for example, La, A element, Si, which are constituent elements of the phosphor matrix, and adjustment of emission wavelength, etc., as necessary Examples thereof include metals, alloys or compounds containing the activating element M added to.
- La source, A source, Si source, and M source compounds include nitrides, oxides, hydroxides, carbonates, nitrates, sulfates, oxalates, and carboxylic acids of the respective elements constituting the phosphor. Examples include salts and halides.
- Specific types may be appropriately selected from these metal compounds in consideration of reactivity to the target product or low generation amount of NOx, SOx, etc. during firing.
- the body is a nitrogen-containing phosphor
- nitrides and oxynitrides include nitrides of elements constituting phosphors such as LaN, Si 3 N 4 or CeN, and phosphors such as La 3 Si 6 N 11 or LaSi 3 N 5 And a composite nitride of the element to be used.
- the phosphor matrix or the phosphor itself may be used as a part of the raw material. Since the phosphor matrix or phosphor has already finished the reaction to become the phosphor matrix, it only contributes to crystal growth, and the phosphor itself has the effect of controlling the crystal diameter and particle diameter in phosphor firing. This is because it can be expected.
- a phosphor production alloy having another composition, a simple metal, a metal compound, etc. are mixed with the phosphor production alloy.
- the composition of the metal element contained in the raw material may be prepared and fired so as to match the composition represented by the formula (2).
- the theoretical composition ratio of (La, A element), Si, and N is preferably 3: 6: 11. Therefore, the charged composition is generally set to the above stoichiometric ratio.
- the La element, the A element, and the M element are appropriate by charging a raw material, particularly La element, in a relatively larger amount than the composition range of the formulas [I] and [II] of the target phosphor of the present invention. It is possible to obtain a crystalline phase that is incorporated in an amount, and to obtain a long-wavelength LYSN phosphor that has a small amount of impurity phase and high emission luminance.
- the molar ratio of La or the element substituting La and La site may be changed in the range of about 1: 2 to 1: 1.5 of the theoretical composition. This change in composition ratio is particularly preferable when the proportion of oxygen in the raw material is high.
- a known method may be used for mixing the phosphor raw materials.
- a method of mixing with a solvent in a pot and crushing the raw material with a ball, a method of mixing by a dry method, and a mesh pass can be used.
- a method of mixing by a dry method and a mesh pass can be used.
- the solvent is removed, and if necessary, dry aggregation is loosened.
- These operations are preferably performed in a nitrogen atmosphere.
- a flux may be used.
- a flux what was described in each gazette of international publication 2008/132951, international publication 2010/114061 etc. can be used, for example.
- the raw material mixture thus obtained is usually filled in a container such as a crucible or a tray and stored in a heating furnace capable of controlling the atmosphere.
- the material of the container is preferably a material having low reactivity with the metal compound, and examples thereof include boron nitride, silicon nitride, carbon, aluminum nitride, molybdenum, and tungsten.
- the firing temperature for the main firing is preferably 1300 ° C. or higher and 1900 ° C. or lower, more preferably 1400 ° C. or higher and 1700 ° C. or lower.
- the main calcination is performed by heating the phosphor raw material in a state filled with hydrogen gas or in a state in which it is circulated, and the pressure at that time is somewhat lower than atmospheric pressure, either atmospheric pressure or pressurized pressure. It may be in a state. However, in order to prevent oxygen from being mixed in the atmosphere, the pressure is preferably set to atmospheric pressure or higher.
- the heating time (maintenance time at the maximum temperature) during the main firing may be a time required for the reaction between the phosphor raw material and nitrogen, but is usually 1 minute or more, preferably 10 minutes or more, more preferably 30 minutes or more, More preferably, it is 60 minutes or more. If the heating time is shorter than 1 minute, the nitriding reaction may not be completed and a phosphor having high characteristics may not be obtained.
- the upper limit of the heating time is determined from the viewpoint of production efficiency, and is usually 50 hours or less, preferably 40 hours or less, more preferably 30 hours or less.
- the firing container filled with the phosphor raw material mixture is placed in a heating furnace.
- the firing apparatus used here is optional as long as the effects of the present invention can be obtained, but an apparatus capable of controlling the atmosphere in the apparatus is preferable, and an apparatus capable of controlling the pressure is also preferable.
- a hot isostatic press (HIP) a resistance heating vacuum pressurizing atmosphere heat treatment furnace, and the like are preferable.
- a gas containing nitrogen in the baking apparatus before starting heating, it is preferable to circulate a gas containing nitrogen in the baking apparatus and sufficiently substitute the nitrogen-containing gas in the system. If necessary, a nitrogen-containing gas may be circulated after the system is evacuated.
- Examples of the nitrogen-containing gas used in firing include a gas containing a nitrogen element, such as nitrogen, ammonia, or a mixed gas of nitrogen and hydrogen. Moreover, only 1 type may be used for nitrogen-containing gas and it may use 2 or more types together by arbitrary combinations and a ratio.
- pulverization step for example, a pulverizer such as a hammer mill, roll mill, ball mill, jet mill, ribbon blender, V-type blender or Henschel mixer, or pulverization using a mortar and pestle can be used.
- a pulverizer such as a hammer mill, roll mill, ball mill, jet mill, ribbon blender, V-type blender or Henschel mixer, or pulverization using a mortar and pestle can be used.
- the washing step is not particularly limited as long as the effects of the present invention are not impaired.
- the phosphor surface can be formed with water such as deionized water, an organic solvent such as ethanol, or an alkaline aqueous solution such as ammonia water.
- hydrochloric acid, nitric acid, sulfuric acid, aqua regia and hydrofluoric acid and sulfuric acid are used for the purpose of improving the luminous characteristics by removing the impurity phase adhering to the phosphor surface, such as removing the used flux.
- An acidic aqueous solution containing an inorganic acid such as a mixture thereof; an organic acid such as acetic acid can also be used.
- a classification process can be performed by using various classifiers, such as a water sieve, various airflow classifiers, or a vibration sieve, for example.
- various classifiers such as a water sieve, various airflow classifiers, or a vibration sieve, for example.
- a phosphor having a volume average diameter of about 10 ⁇ m and excellent dispersibility can be obtained.
- a phosphor with good dispersibility having a volume median diameter of about 20 ⁇ m can be obtained.
- the phosphor after the washing is dried at about 100 ° C. to 200 ° C. You may perform the dispersion
- the phosphor of the present invention may be used by mixing with a liquid medium.
- the phosphor of the present invention when used for applications such as a light emitting device, it is preferably used in a form dispersed in a liquid medium.
- a material in which the phosphor of the present invention is dispersed in a liquid medium is appropriately referred to as “a phosphor-containing composition according to the present invention” or the like.
- the fluorescent substance of this invention contained in the fluorescent substance containing composition which concerns on this invention may be only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.
- the phosphor-containing composition according to the present invention may contain a phosphor other than the phosphor of the present invention as long as the effects of the present invention are not significantly impaired.
- liquid medium used in the phosphor-containing composition according to the present invention is not particularly limited as long as the performance of the phosphor is not impaired within the intended range.
- any inorganic material and / or organic material may be used as long as it exhibits liquid properties under the desired use conditions, suitably disperses the phosphor of the present invention, and does not cause an undesirable reaction.
- examples thereof include silicone resin, epoxy resin, and polyimide silicone resin.
- the content of the phosphor and the liquid medium in the phosphor-containing composition according to the present invention is arbitrary as long as the effects of the present embodiment are not significantly impaired, but for the liquid medium, the phosphor-containing composition according to the present invention.
- the total amount is usually 50% by weight or more, preferably 75% by weight or more, and usually 99% by weight or less, preferably 95% by weight or less.
- the phosphor-containing composition according to the present invention may contain other components in addition to the phosphor and the liquid medium as long as the effects of the present invention are not significantly impaired. Moreover, only 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and a ratio.
- the light-emitting device of the present invention is a light-emitting device including a first light-emitting body (excitation light source) and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body.
- the phosphor of 2 contains the phosphor of the present invention.
- any one of the phosphors of the present invention may be used alone, or two or more thereof may be used in any combination and ratio.
- the phosphor of the present invention for example, a phosphor that emits yellow-green or yellow region fluorescence under irradiation of light from an excitation light source is used.
- the yellow-green to yellow phosphor of the present invention preferably has a light emission peak in a wavelength range of 546 nm or more and 570 nm or less.
- the excitation source one having an emission peak in a wavelength range of less than 420 nm may be used.
- a light emitting device in which the phosphor of the present invention has a light emission peak in the wavelength range of 546 nm or more and 570 nm or less and the first light emitter has a light emission peak in the wavelength range of 350 nm or more and 460 nm or less.
- the present embodiment is not limited to these.
- the light emitting device of the present invention can be set, for example, in the following manner. That is, as the first light emitter, one having a light emission peak in the wavelength range of 350 nm to 460 nm is used, and as the first phosphor of the second light emitter, the light emission peak is present in the wavelength range of 535 nm to 600 nm. It can be set as the aspect using at least 1 sort (s) of fluorescent substance (phosphor of this invention).
- the light emitting device of the present invention may further contain a yellow phosphor having an emission peak in a wavelength range of 546 nm or more and 570 nm or less.
- the following phosphors are preferably used.
- the garnet phosphor include (Y, Gd, Lu, Tb, La) 3 (Al, Ga) 5 O 12 : (Ce, Eu, Nd)
- the orthosilicate include (Ba, Sr, Ca, Mg) 2 SiO 4 : (Eu, Ce)
- Examples of (acid) nitride phosphors include (Ba, Ca, Mg) Si 2 O 2 N 2 : Eu (SION phosphor), (Li, Ca) 2 (Si, Al) 12 (O, N 16 : (Ce, Eu) ( ⁇ -sialon phosphor), (Ca, Sr) AlSi 4 (O, N) 7 : (Ce, Eu) (1147 phosphor), (La, Ca) 3 (Al, Si) 6 N 11 : Ce (LSN phosphor) Etc.
- the LSN fluorescent substance with which specific gravity of a fluorescent substance does not change largely is preferable.
- the light emitting device of the present invention may further contain a red phosphor.
- a red phosphor for example, the following phosphors are preferably used.
- Mn-activated fluoride phosphor examples include, for example, K 2 (Si, Ti) F 6 : Mn, K 2 Si 1-x Na x Al x F 6 : Mn (0 ⁇ x ⁇ 1) (collectively KSF fluorescence) body),
- sulfide phosphors include (Sr, Ca) S: Eu (CAS phosphor), La 2 O 2 S: Eu (LOS phosphor),
- the garnet phosphor include (Y, Lu, Gd, Tb) 3 Mg 2 AlSi 2 O 12 : Ce,
- nanoparticles include CdSe,
- As the nitride or oxynitride phosphor for example, (Sr, Ca) AlSiN 3 : Eu (S / CASN phosphor), (CaAlSiN 3 ) 1-x ⁇ (SiO 2 N 2 ) x: Eu (CAUON fluorescence) Body), (La, Ca) 3 (Al, Si) 6 N 11 :
- the red phosphor is preferably a KSF phosphor or an S / CASN phosphor.
- the light emitting device of the present invention may further contain a green phosphor.
- the green phosphor in the present invention is a phosphor having an emission peak wavelength of 510 to 545 nm.
- the following phosphors are preferably used.
- Examples of the garnet phosphor include (Y, Gd, Lu, Tb, La) 3 (Al, Ga) 5 O 12 : (Ce, Eu, Nd), Ca 3 (Sc, Mg) 2 Si 3 O 12. : (Ce, Eu) (CSMS), Examples of the silicate phosphor include (Ba, Sr, Ca, Mg) 3 SiO 10 : (Eu, Ce), (Ba, Sr, Ca, Mg) 2 SiO 4 : (Ce, Eu) (BSS phosphor).
- oxide phosphor for example, (Ca, Sr, Ba, Mg) (Sc, Zn) 2 O 4 : (Ce, Eu) (CASO phosphor)
- oxide phosphor for example, (Ca, Sr, Ba, Mg) (Sc, Zn) 2 O 4 : (Ce, Eu) (CASO phosphor)
- (acid) nitride phosphors include (Ba, Sr, Ca, Mg) Si 2 O 2 N 2 : (Eu, Ce), Si 6-z Al z O z N 8-z : (Eu, Ce) ( ⁇ -sialon phosphor) (0 ⁇ z ⁇ 1), (Ba, Sr, Ca, Mg, La) 3 (Si, Al) 6 O 12 N 2 : (Eu, Ce) (BSON phosphor) , (La, Ca) 3 (Al, Si) 6 N 11 : Ce (LSN phosphor)
- As the aluminate phosphor for example
- the light-emitting device of the present invention has a first light emitter (excitation light source), and at least the phosphor of the present invention is used as the second light emitter. It is possible to arbitrarily adopt the apparatus configuration.
- Examples of the device configuration and the light emitting device include those described in Japanese Patent Application Laid-Open No. 2007-291352.
- examples of the form of the light emitting device include a shell type, a cup type, a chip on board, a remote phosphor, and the like.
- the application of the light-emitting device of the present invention is not particularly limited and can be used in various fields where ordinary light-emitting devices are used. However, since the color reproduction range is wide and the color rendering property is high, illumination is particularly important. It is particularly preferably used as a light source for a device or an image display device.
- the illuminating device of this invention is equipped with the light-emitting device of this invention as a light source, It is an illuminating device characterized by the above-mentioned.
- the above-described light-emitting device may be appropriately incorporated into a known lighting device.
- a surface emitting illumination device in which a large number of light emitting devices are arranged on the bottom surface of the holding case can be used.
- the image display device of the present invention is an image display device including the light emitting device of the present invention as a light source.
- the specific configuration of the image display device is not limited, but is preferably used with a color filter.
- the image display device is a color image display device using color liquid crystal display elements
- the light emitting device is used as a backlight, a light shutter using liquid crystal, and a color filter having red, green, and blue pixels; By combining these, an image display device can be formed.
- the sintered phosphor according to the present invention and a light emitting device, an illumination device, an image display device, and a vehicular lamp / indicator using the sintered phosphor will be described.
- the sintered phosphor in the present invention described below, and a light emitting device, an illumination device, an image display device, and a vehicle lamp / indicator using the sintered phosphor may be referred to as “invention 2”.
- the sintering temperature can be lowered as compared with the case where Al 2 O 3 is used as an inorganic binder, so that the reaction between the nitride phosphor and the inorganic binder is suppressed. Can be made.
- the present inventors have conceived that a sintered phosphor of a nitride phosphor having a high internal quantum efficiency can be obtained.
- Al 2 O 3 which is a trigonal system has birefringence. Therefore, when it is a sintered body, Al 2 O 3 becomes a polycrystal and has insufficient translucency, whereas CaF 2 and BaF 2. If a fluoride inorganic binder having a crystal system such as SrF 2 is used, a sintered phosphor having no birefringence and high transparency can be produced.
- a sintered phosphor suitable for illumination at a particularly low color temperature can be obtained.
- the present inventors have invented a sintered phosphor for LED that can develop a low color temperature with many red components and has high internal quantum efficiency and high transmittance by using a specific nitride phosphor. It came to. Furthermore, using this sintered phosphor, it is possible to emit light with a high color efficiency, high brightness, low brightness and high color components, low brightness and color shift due to changes in excitation light intensity and temperature, and a large amount of red component. It came to invent the outstanding light-emitting device and illuminating device which can be performed.
- the present invention is a sintered phosphor containing a nitride phosphor and a fluoride inorganic binder
- the nitride phosphor is a phosphor containing a crystal phase represented by the following formula [10].
- the sintered phosphor, the light-emitting device, the illumination device, the image display device, and the vehicular lamp / indicator lamp are characterized as follows. ⁇ 1> A sintered phosphor containing a nitride phosphor and a fluoride inorganic binder, A sintered phosphor, wherein the nitride phosphor is a phosphor containing a crystal phase represented by the following formula [1].
- La w10 A x10 Si 6 N y10 M z10 [10] (M element in the formula represents one or more elements selected from activators, The A element represents one or more elements selected from rare earth elements other than La and an activating element, 2.0 ⁇ w10 ⁇ 4.0, 0 ⁇ x10 ⁇ 1.5, 8.0 ⁇ y10 ⁇ 14.0, 0.05 ⁇ z10 ⁇ 1.0) ⁇ 2>
- the fluorescence of the phosphor containing the crystal phase represented by the formula [1] obtained by irradiating excitation light having a wavelength of 455 nm is expressed by chromaticity coordinates x and y expressed in the CIE1931XYZ color system.
- the sintered phosphor according to ⁇ 1> characterized in that the following formula is satisfied. 0.43 ⁇ x ⁇ 0.50, 0.48 ⁇ y ⁇ 0.55 ⁇ 3>
- ⁇ 4> The sintered phosphor according to any one of ⁇ 1> to ⁇ 3>, further comprising one or more other phosphors.
- ⁇ 5> The sintered phosphor according to any one of ⁇ 1> to ⁇ 4>, and an LED or a semiconductor laser as a light source, The sintered phosphor emits light having different wavelengths by absorbing at least a part of light from the light source.
- ⁇ 6> The light emitting device according to ⁇ 5>, wherein the correlated color temperature of light emission is 5000 K or less.
- a lighting device comprising the light-emitting device according to ⁇ 5> or ⁇ 6>.
- An image display device comprising the light emitting device according to ⁇ 5> or ⁇ 6>.
- a vehicle lamp / indicator comprising the light-emitting device according to ⁇ 5> or ⁇ 6>.
- a sintered phosphor for LED having high internal quantum efficiency and high transmittance can be provided.
- a sintered phosphor capable of obtaining light emission with a low color temperature can be provided.
- the light emission efficiency is high, the brightness is high, the brightness change and the color shift due to the change of the excitation light intensity and the temperature are small, and the light of the low color temperature with a lot of red component is emitted. It is possible to provide a light emitting device that emits light, a lighting device using the light emitting device, and a vehicle lamp / indicator lamp.
- a sintered phosphor according to an embodiment of the present invention includes a nitride phosphor and a fluoride inorganic binder, and the nitride phosphor includes a crystal phase represented by the formula [10] (hereinafter, referred to as “phosphor”). It may be referred to as “Formula [10] Phosphor”.
- the sintered phosphor in the present invention is not particularly limited as long as it is a composite composed of a nitride phosphor containing the formula [10] phosphor and a fluoride inorganic binder, but preferably, the nitride phosphor is a fluoride. It is a composite in which the nitride phosphor and the fluoride inorganic binder are integrated by physical and / or chemical bonding.
- nitrides and fluorides By combining nitrides and fluorides with different ionic radii, it is possible to suppress the reaction between the nitride phosphor and the fluoride inorganic binder during sintering, and obtain a sintered phosphor with high internal quantum efficiency. is there.
- Such a sintered phosphor can be obtained by observing the surface of the sintered phosphor with a scanning electron microscope, cutting out the cross section by cutting the sintered phosphor, or creating a cross section of the sintered phosphor with a cross section polisher. Observation is possible by an observation method such as cross-sectional observation of a sintered phosphor by a scanning electron microscope.
- Niride phosphor In the sintered phosphor according to the embodiment of the present invention, as a method for confirming the presence of the nitride phosphor, the identification of the nitride phosphor phase by X-ray diffraction and the energy dispersive X-ray analyzer are used. Elemental analysis of particles, elemental analysis using fluorescent X-rays, and the like can be given.
- the sintered phosphor of this embodiment contains a phosphor containing a crystal phase represented by the following formula [10].
- the phosphor of the formula [10] phosphor shifts its emission wavelength to a long wavelength and exhibits emission spectra suitable for use as various light emitting devices.
- x10 represents the content of element A and is usually in the range of 0 ⁇ x10 ⁇ 1.5, and the lower limit is preferably 0.1, more preferably 0.2, still more preferably 0.3, The upper limit value is preferably 1.0, more preferably 0.7. Within the above range, the emission intensity is unlikely to decrease, which is preferable.
- W10 represents the content of La and is usually in the range of 2.0 ⁇ w10 ⁇ 4.0.
- the sum of w10, x10, and z10 is preferably 3 in terms of the crystal structure, but may be a value other than 3 due to the presence of lattice defects, interstitial elements, and impurity elements.
- it is preferable that the fluctuation range from 3 which is the stoichiometric ratio of W10 is within 20% because the crystal structure of the formula [10] phosphor is easily maintained. That is, W10 is preferably 2.4 or more, and preferably 3.6 or less.
- Y10 represents the content of N and is usually in the range of 8.0 ⁇ y10 ⁇ 14.0. y10 is preferably 11 in terms of the crystal structure, but may have a value other than 11 due to the presence of lattice defects, interstitial elements, and impurity elements.
- z10 represents the content of M element, and is generally 0.05 ⁇ z10 ⁇ 1.0.
- the lower limit is preferably 0.10, more preferably 0.2, and the upper limit is preferably 0.95. More preferably, it is 0.9. Within the above range, concentration quenching is difficult and light emission intensity is hardly lowered.
- content of each above-mentioned element is shown by molar ratio.
- the mass ratio of oxygen atoms in the phosphor of formula [10] is preferably 5.0% or less, more preferably 3.0% or less, and even more preferably 1.0% or less. Since nitride phosphors inevitably contain oxygen, the lower limit is usually greater than 0%. It is preferable for it to be within the above-mentioned range since the resulting sintered phosphor has good luminance.
- the phosphor of the formula [10] is based on La 3 Si 6 N 11 and is obtained by substituting Y, Gd, etc. having an ionic radius smaller than La instead of La, and the lattice constant thereof is as follows.
- the a-axis lattice constant (lattice constant a) is preferably a value satisfying 10.104 cm or more and 10.185 cm or less, and its lower limit value is more preferably 10.109 cm, and even more preferably 10.114 m, The upper limit value is more preferably 10.17 cm, and further preferably 10.16 cm.
- the b-axis lattice constant (lattice constant b) is the same value as the lattice constant a.
- the c-axis lattice constant (lattice constant c) is a value that usually satisfies 4.820 ⁇ or more and 4.860 ⁇ or less, and its lower limit is preferably 4.825 ⁇ , more preferably 4.830 ⁇ ,
- the upper limit value is preferably 4.865cm, more preferably 4.860mm.
- the lattice constant a is in the above range since a phosphor exhibiting an emission spectrum suitable for illumination at a low color temperature below 5000K can be obtained.
- the lattice constant c it is particularly preferable that the lattice constant a is 10.154 mm or less because a phosphor exhibiting an emission spectrum suitable for light bulb color illumination can be obtained.
- said lattice constant is the diffraction pattern estimated from the crystal structure of the tetragonal crystal of space group P4bm in which the powder X-ray diffraction pattern of the phosphor of formula [10] is reported as the crystal structure of La 3 Si 6 N 11 And is determined using the diffraction angle data of powder X-ray diffraction and the index of the diffraction of the formula [10] phosphor. Although it can be calculated using a specific diffraction line and its index, it is usually calculated by pattern fitting (for example, Rietveld analysis method) using a plurality of diffraction lines or all measured diffraction lines.
- pattern fitting for example, Rietveld analysis method
- Phosphor ⁇ [Luminescent color]
- the phosphor emits light when excited by irradiating excitation light having a wavelength of 455 nm
- the chromaticity coordinates x and y expressed in the CIE (International Commission on Illumination) 1931XYZ color system are as follows: It is preferable to satisfy. 0.43 ⁇ x ⁇ 0.50, 0.48 ⁇ y ⁇ 0.55
- the chromaticity coordinates x and y are calculated using the spectrum of only the phosphor excluding the excitation light that was not absorbed by the phosphor from the measured spectrum.
- the value of the chromaticity coordinate x is preferably 0.43 or more, more preferably 0.44 or more, further preferably 0.45 or more, particularly preferably 0.46 or more, and preferably 0.50 or less. 495 or less is more preferable, and 0.49 or less is more preferable. By taking such a range, it is preferable because warm emission (bulb color) of white light of 3000K to 5000K can be obtained when excited with a gallium nitride blue LED or laser.
- the value of chromaticity coordinate y changes in conjunction with the value of chromaticity coordinate x. That is, as x increases, y decreases.
- the value of y is preferably 0.48 or more, more preferably 0.49 or more, preferably 0.55 or less, and more preferably 0.54 or less.
- the formula [10] phosphor preferably has the following characteristics when an emission spectrum is measured when excited by light having a wavelength of 300 nm or more and 460 nm or less.
- the peak wavelength in the above-mentioned emission spectrum of the phosphor of the present invention is usually 546 nm or more, preferably 550 nm or more, and usually 570 nm or less, preferably 565 nm or less. Within the above range, the obtained phosphor is preferable in that it exhibits a good green or yellow color.
- the volume median diameter of the formula [10] phosphor is usually 0.1 ⁇ m or more, preferably 0.5 ⁇ m or more, and is usually 35 ⁇ m or less, preferably 25 ⁇ m or less. By setting it as the said range, since the fall of a brightness
- the volume median diameter can be measured by, for example, a Coulter counter method, and a typical apparatus is a precision particle size distribution measuring device Multisizer (manufactured by Beckman Coulter, Inc.).
- volume fraction of phosphor The volume fraction of the formula [10] phosphor with respect to the total volume of the sintered phosphor is usually 1% or more and 50% or less. The volume fraction is affected by the size, thickness, shape, surface roughness, structure of the light emitting device, etc. of the sintered phosphor, and is a parameter that should be adjusted to obtain the desired emission color. If the volume fraction of the phosphor is too low, sufficient wavelength conversion cannot be performed, and if the volume fraction is too high, the wavelength conversion efficiency decreases or the content of the fluoride inorganic binder is too low. It becomes difficult to produce a sintered phosphor having a high mechanical strength.
- a preferable range of the volume fraction is 3% or more and 20% or less, and 15% or less. More preferably it is. If the thickness is reduced, the volume fraction is increased, and if the thickness is increased, the volume fraction is decreased.
- the sintered fluorescent substance of this embodiment contains fluorescent substance other than Formula [10] fluorescent substance, it is preferable that the said volume fraction becomes in the said range also including other fluorescent substance.
- the contained formula [10] phosphor may be only one type, or may contain two different types. Examples of the two different types include those having different compositions, different particle sizes, and different chromaticities.
- the method for producing the formula [10] phosphor is not particularly limited as long as the formula [10] phosphor and its effects can be obtained, but a preferable production method will be described below.
- the phosphor production alloy when the phosphor production alloy is not used or the composition does not match, a phosphor production alloy having another composition, a simple metal, a metal compound, etc. are mixed with the phosphor production alloy.
- the metal element composition contained in the raw material can be prepared and fired so as to match the composition represented by the formula [10].
- the La element, the A element, and the M element are appropriately obtained by charging a raw material, particularly La element, relatively larger than the composition range of the target phosphor.
- a crystal phase in which a sufficient amount is incorporated can be obtained, and the phosphor of formula [10] having high emission luminance with few impurity phases can be obtained.
- the composition of the metal element charge can be appropriately adjusted and determined with reference to the method described in Invention 1.
- the theoretical composition ratio of (La, A element) and Si and N is 3: 6: 11. preferable.
- the molar ratio of Si and the total of the elements substituting La and La sites may be changed within the range of 1: 2 to 1: 1.5 of the theoretical composition. This change in composition ratio is particularly preferable when the proportion of oxygen in the raw material is high.
- a known method may be used for mixing the phosphor raw materials.
- a method of mixing with a solvent in a pot and crushing the raw material with a ball, a method of mixing by a dry method, and a mesh pass can be used.
- a method of mixing by a dry method and a mesh pass can be used.
- the solvent is removed, and if necessary, dry aggregation is loosened.
- These operations are preferably performed in a nitrogen atmosphere.
- ⁇ Fluoride inorganic binder ⁇ [Fluoride inorganic binder and fluoride inorganic binder particles]
- the identification of the inorganic binder phase by X-ray diffraction, the surface of the sintered body or the cross-sectional structure by an electron microscope Observation and elemental analysis, and elemental analysis by fluorescent X-rays as a method for confirming the presence of the fluoride inorganic binder, the identification of the inorganic binder phase by X-ray diffraction, the surface of the sintered body or the cross-sectional structure by an electron microscope Observation and elemental analysis, and elemental analysis by fluorescent X-rays.
- the total volume fraction of the nitride phosphor and the fluoride inorganic binder with respect to the total volume of the sintered phosphor is preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more. This is because if the total volume fraction is low, the effects of the present invention cannot be exhibited.
- the total volume fraction may be lower than the preferred range. Permissible.
- the volume fraction of the fluoride inorganic binder with respect to the total volume of the nitride phosphor and the fluoride inorganic binder is usually 50% or more, preferably 60% or more, more preferably 70% or more, and usually 99% by volume or less. Preferably it is 98% or less, More preferably, it is 97% or less.
- the fluoride inorganic binder is used as a matrix for dispersing the nitride phosphor.
- the matrix may contain other than the fluoride inorganic binder, but is preferably a crystalline compound.
- the fluoride inorganic binder is preferably one that transmits a part of the excitation light emitted from the light emitting element or at least a part of the light emitted from the nitride phosphor. In order to efficiently extract light emitted from the nitride phosphor, it is preferable that the refractive index of the fluoride inorganic binder is close to the refractive index of the phosphor.
- the moldability of a sintered fluorescent substance becomes favorable by using a fluoride inorganic binder.
- the fluoride inorganic binder examples include CaF 2 (calcium fluoride), MgF 2 (magnesium fluoride) , BaF 2 (barium fluoride), SrF 2 (strontium fluoride), and LaF 3 (lanthanum fluoride). ), YF 3 (yttrium fluoride), AlF 3 (aluminum fluoride) and other alkaline earth metals, rare earth metal fluorides and typical metals, and any one or more selected from the group consisting of these composites Is used as the main component.
- the main component means that 50% by weight or more is occupied as the fluoride inorganic binder to be used.
- CaF 2 is preferably used as the fluoride inorganic binder from the viewpoint of cost and ease of sintering.
- a composite containing 50% by weight or more of CaF 2 is used as the fluoride inorganic binder, more preferably a composite containing 80% by weight or more, and a composite containing 90% by weight or more. It is particularly preferred.
- the fluoride inorganic binder may contain a halide, oxide or nitride other than these in an amount of 5% or less.
- the fluoride inorganic binder is configured by physically and / or chemically bonding particles having the same composition as the fluoride inorganic binder.
- the fluoride inorganic binder particles have a volume median diameter of usually 0.01 ⁇ m or more, preferably 0.02 ⁇ m or more, more preferably 0.03 ⁇ m or more, and particularly preferably 0.05 ⁇ m or more. It is 15 ⁇ m or less, preferably 10 ⁇ m or less, more preferably 5 ⁇ m or less, still more preferably 3 ⁇ m or less, and particularly preferably 2 ⁇ m or less.
- the sintering temperature can be reduced, and the deactivation of the nitride phosphor due to the reaction between the nitride phosphor and the inorganic binder can be suppressed, A decrease in internal quantum efficiency of the sintered phosphor can be suppressed.
- the volume median diameter can be measured by, for example, the above-mentioned Coulter counter method, and other representative apparatuses include laser diffraction particle size distribution measurement, scanning electron microscope (SEM), transmission electron microscope (TEM), precision particle size. Measurement is performed using a distribution measuring device Multisizer (manufactured by Beckman Coulter).
- Examples of methods for confirming the purity of the fluoride inorganic binder particles include inductively coupled plasma emission spectroscopic analysis (ICP-AES analysis) and elemental quantitative analysis using fluorescent X-rays.
- ICP-AES analysis inductively coupled plasma emission spectroscopic analysis
- elemental quantitative analysis using fluorescent X-rays ICP-AES analysis
- the purity of the fluoride inorganic binder particles is usually 99% or more, preferably 99.5% or more, more preferably 99.9% or more. Within the above range, foreign matter is hardly generated after sintering, and the sintered body characteristics such as permeability and luminous efficiency are good, which is preferable.
- a sintered body made of fluoride inorganic binder particles is mirror-polished and used to obtain the minimum deflection angle method, critical angle method, V block The method of measuring by a method is mentioned.
- the refractive index nb of the fluoride inorganic binder particles is such that the ratio nb / np to the refractive index np of the nitride phosphor is usually 1 or less, preferably 0.8 or less, more preferably 0.6 or less. If the refractive index ratio is greater than 1, the light extraction efficiency after sintering tends to be reduced. For this reason, the said range is preferable.
- ⁇ Thermal conductivity As a method for confirming the thermal conductivity of fluoride inorganic binder particles, a sintered body made of fluoride inorganic binder particles is prepared, and a steady heating method, laser flash method, and periodic heating are used. The method of measuring by a method is mentioned.
- the thermal conductivity of the fluoride inorganic binder particles is usually 3.0 W / (m ⁇ K) or more, preferably 5.0 W / (m ⁇ K) or more, more preferably 10 W / (m ⁇ K) or more. is there.
- the thermal conductivity is less than 3.0 W / (m ⁇ K)
- the temperature of the sintered phosphor may increase due to irradiation with strong excitation light, and the phosphor and peripheral members tend to be deteriorated. For this reason, the said range is preferable.
- particles of components other than the phosphor can be added for the purpose of adjusting the refractive index and improving the thermal conductivity.
- particles for the above purpose particles having low light absorption and excellent thermal conductivity are preferable, and boron nitride, silicon nitride, aluminum nitride, alumina, and magnesia are preferable. From the viewpoint of heat dissipation, boron nitride is preferable, and from the viewpoint of low light absorption, alumina, magnesia, and silicon oxide are preferable.
- the volume fraction of the particles in the sintered phosphor is preferably 50% or less, and more preferably 30% or less. If the amount is too large, the sintered phosphor may not have a mechanical strength necessary for practical use.
- the particle size of the particles is preferably 10 microns or less, more preferably 5 microns or less, and particularly preferably 2 microns or less. The smaller the particle size, the easier it is to disperse uniformly in the fluoride inorganic binder, and it becomes easier to obtain a homogeneous sintered phosphor.
- the fluoride inorganic binder particles preferably have a low melting point.
- fluoride inorganic binder particles having a low melting point it becomes possible to reduce the sintering temperature, and can suppress the deactivation of the nitride phosphor due to the reaction between the nitride phosphor and the inorganic binder, A decrease in internal quantum efficiency of the sintered phosphor can be suppressed.
- the melting point is preferably 1500 ° C. or lower, and more preferably 1300 ° C. or lower.
- the lower limit temperature is not particularly limited and is usually 500 ° C. or higher.
- solubility of the fluoride inorganic binder particles is 0.05 g or less per 100 g of water at 20 ° C.
- the sintered phosphor of this embodiment may contain other phosphors other than the formula [10] phosphor as long as the effects of the present invention are not impaired.
- Other phosphors may be (oxy) nitride phosphors, oxide phosphors, or both of them.
- ((Acid) nitride phosphor) examples include the following.
- Nitride phosphors containing strontium and silicon in the crystal phase specifically, SCASN ((Ca, Sr, Ba, Mg) AlSiN 3 : Eu and / or (Ca, Sr, Ba) AlSi (N, O) 3 : Eu)), Sr 2 Si 5 N 8 : Eu), a nitride phosphor containing calcium and silicon in the crystal phase (specifically, SCASN, CASN (CaAlSiN 3 : Eu), CASON ((CaAlSiN 3 ) 1 ) -X (Si 2 N 2 O) x : Eu (where 0 ⁇ x ⁇ 0.5))), strontium, silicon, and aluminum in the crystalline phase (specifically, SCASN, Sr 2 Si 5 N 8 : Eu), calcium, silicon, and a nitride phosphor (specifically, SCASN, CASN, CASON) containing aluminum in the crystal phase.
- SCASN ((Ca, Sr, Ba,
- ⁇ sialon that can be represented by the following general formula: Si 6-z Al z O z N 8-z : Eu (where 0 ⁇ z ⁇ 4.2), ⁇ sialon, LSN represented by the following general formula: Ln x Si y N n : Z (wherein Ln is a rare earth element excluding an element used as an activating element. Z is an activating element.
- CASN CaAlSiN 3 : Eu represented by the following general formula: SCASN: (Ca, Sr, Ba, Mg) AlSiN 3 : Eu and / or (Ca, Sr, Ba) AlSi (N, O) 3 : Eu), which can be represented by the following general formula: CASON that can be represented by the following general formula: (CaAlSiN 3 ) 1-x (Si 2 N 2 O) x : Eu (where 0 ⁇ x ⁇ 0.5), CaAlSi 4 N 7 : (Sr, Ca, Ba) 1-y Al 1 + x Si 4 ⁇ x O x N 7 ⁇ x : Eu y (where 0 ⁇ x ⁇ 4, 0 ⁇ y ⁇ 0.2), Sr 2 Si 5 N 8 : Eu that can be expressed by the following general formula, that is, (Sr, Ca, Ba) 2 Al
- nitride phosphor not containing oxygen as a constituent element that is, LSN
- LSN nitride phosphor not containing oxygen as a constituent element (including inevitably mixed oxygen)
- CASN CASN
- SCASN Sr 2 Si 5 N 8 : Eu
- ⁇ sialon nitride phosphors
- a sintered phosphor containing both the LSN phosphor and the formula [10] phosphor is preferable because it can produce a light emitting device having an excellent balance between luminous efficiency and color rendering.
- the LSN phosphor preferably has all Ln in the above formula as La.
- the sintered phosphor containing two kinds of phosphors is preferable in terms of easy production because the influence of the phosphor lot-to-lot variation can be adjusted by the blending ratio of the two kinds of phosphors during mass production.
- the correlated color temperature of the light emitting device manufactured with this configuration is preferably 3000 K or higher, more preferably 4000 K or higher, and preferably 6500 K or lower. Illumination with a high correlated color temperature is bright because it contains a relatively large amount of light with high visibility.
- the sintered phosphor containing both the CASN phosphor or the SCASN phosphor and the formula [10] phosphor can be suitably used for a light emitting device that emits light at a low color temperature, and has an excellent balance between luminous efficiency and color rendering. It is preferable because a light emitting device can be manufactured.
- oxide phosphor examples include the following.
- An oxide phosphor having a garnet structure such as Y 3 Al 5 O 12 : Ce, Lu 3 Al 5 O 12 : Ce can be used.
- Y can be replaced with Gd, Tb, and Lu
- Al can be replaced with Ga
- Lu can be replaced with Gd, Tb, and Y.
- silicate phosphors such as Ca 3 Sc 2 Si 3 O 12 : Ce, Ca 3 Sc 2 Si 3 O 12 : Ce, Mg, Lu 2 CaMg 2 Si 3 O 12 : Ce can be used.
- An aluminate phosphor such as SrAl 2 O 4 : Eu and Sr 4 Al 14 O 25 : Eu can also be used.
- particle size and volume fraction in the above (oxy) nitride phosphor and oxide phosphor are the same as those described in the section of the formula [10] phosphor.
- the preferred embodiment is also the same.
- Y 3 Al 5 O 12: Y was partially substituted with Ga with Ce or Al 3 Al 5 O 12: and Ce, sintered phosphor containing both the formula [10] phosphor luminous efficiency and color rendering It is preferable because a light emitting device having an excellent balance can be produced.
- the correlated color temperature of the light emitting device manufactured with this configuration is preferably 5000 K or higher, and more preferably 6000 K or higher.
- Step 1 Step of stirring and mixing nitride phosphor (or garnet-based phosphor and nitride phosphor) and inorganic binder particles, press-pressing, and sintering the molded body (Step 2) nitride fluorescence
- the body (or garnet phosphor and nitride phosphor) and inorganic binder particles are agitated and mixed and sintered simultaneously with the pressure press
- a nitride phosphor (or garnet phosphor and nitride phosphor) and inorganic binder particles are mixed to obtain a mixed powder of the nitride phosphor and the like and inorganic binder particles.
- the volume fraction of the fluoride inorganic binder is usually 50% or more, preferably 60% or more, more preferably 70% or more. Yes, usually 99% or less, preferably 98% or less, more preferably 97% or less.
- a method of stirring and mixing these is, for example, a dry mixing method such as a ball mill or a V blender, or a slurry is added to a nitride phosphor or an inorganic binder to form a slurry, and a ball mill, homogenizer, ultrasonic homogenizer, biaxial Examples thereof include a wet mixing method using a kneader and the like.
- the stirring / mixing time is usually 0.5 hours or longer, preferably 2 hours or longer, more preferably 6 hours or longer, and usually 72 hours or shorter, preferably 48 hours or shorter, more preferably 24 hours or shorter.
- the whole can be mixed uniformly by mechanically stirring and mixing.
- an organic binder, a dispersant, and a solvent may be added in order to improve the formability by a pressure press.
- the organic binder is usually 0.1 wt% or more and 5 wt% or less
- the dispersant is usually 0.01 wt% or more and 3 wt% or less.
- the solvent is usually mixed in an amount of 10 wt% to 70 wt% to prepare a slurry.
- polyvinyl alcohol polyacrylic acid, polyvinyl butyral, methylcellulose, starch or the like can be used as the organic binder.
- dispersant stearic acid, sodium dodecylbenzenesulfonate, ammonium polycarboxylate, or the like can be used.
- solvent water, methyl alcohol, ethyl alcohol, isopropyl alcohol, or the like can be used. These may be used alone or in combination.
- Examples of the method of mixing these include a wet mixing method using a ball mill, a homogenizer, an ultrasonic homogenizer, a twin-screw kneader, or the like.
- the stirring / mixing time is usually 0.5 hours or longer, preferably 2 hours or longer, more preferably 6 hours or longer, usually 72 hours or shorter, preferably 48 hours or shorter, more preferably 24 hours. Below time.
- the solvent drying / granulation step is performed after the stirring / mixing step.
- the slurry obtained by the stirring / mixing step is volatilized at a predetermined temperature to obtain a mixed powder of nitride phosphor and the like, inorganic binder particles, and organic binder.
- the average particle diameter of the granulated particles is usually 22 ⁇ m or more, preferably 24 ⁇ m or more, more preferably 26 ⁇ m or more, and usually 200 ⁇ m or less, preferably 150 ⁇ m or less, more preferably 100 ⁇ m or less. If the granulated particle size is small, the bulk density becomes small, powder handling properties, filling the press mold becomes difficult, and if the granulated particle size is large, pores remain in the molded body after pressing, This leads to a decrease in the degree of sintering.
- the mixed powder obtained in the stirring / mixing process is press-molded using uniaxial mold molding and cold isostatic pressing (CIP) to obtain a green body having a desired shape.
- the pressure during molding is usually 1 MPa or more, preferably 5 MPa or more, more preferably 10 MPa or more, and usually 1000 MPa or less. If the pressure at the time of molding is too low, a molded body cannot be obtained, and if the pressure is too high, the phosphor may be mechanically damaged and the light emission characteristics may be reduced.
- degreasing is performed by burning out the organic binder components in the air from the green body formed using the organic binder.
- the furnace used for degreasing is not particularly limited as long as a desired temperature and pressure can be realized.
- a reactor such as a shuttle furnace, a tunnel furnace, a lead hammer furnace, an autoclave, a Tamman furnace, an Atchison furnace, a hot press apparatus, a pulsed current pressure sintering apparatus, a hot static furnace, etc.
- a high-pressure induction heating furnace, direct resistance heating, indirect resistance heating, direct combustion heating, radiant heat heating, electric heating, or the like can also be used as the water pressure sintering apparatus, pressurized atmosphere furnace, and heating method. During the treatment, stirring may be performed as necessary.
- the atmosphere of the degreasing treatment is not particularly limited, but it is preferably carried out in the air or under an air flow.
- the degreasing treatment temperature varies depending on the inorganic binder used, but is usually 300 ° C or higher, preferably 400 ° C or higher, more preferably 500 ° C or higher, and usually 1200 ° C or lower, preferably 1100 ° C or lower, more preferably Is 1000 ° C. or lower.
- the degreasing treatment time is usually 0.5 hours or more, preferably 1 hour or more, more preferably 2 hours or more, and usually 6 hours or less, preferably 5 hours or less, more preferably 4 hours or less.
- the processing temperature and time are smaller than this range, the organic components cannot be sufficiently removed.
- the processing temperature and time are larger than this range, the surface of the phosphor, such as oxidized, is altered and tends to cause deterioration of the light emission characteristics. .
- the heat history temperature condition, the heating rate, the cooling rate, the heat treatment time, etc. can be set as appropriate. Further, after heat treatment in a relatively low temperature region, the temperature can be raised to a predetermined temperature.
- the reactor used for this process may be a batch type or a continuous type, and may be one or more.
- a sintered fluorescent substance is obtained by sintering the molded object obtained through the formation process and / or the degreasing process.
- the process used for sintering is not particularly limited as long as the desired temperature and pressure can be realized.
- reactors such as shuttle furnaces, tunnel furnaces, reed hammer furnaces, autoclaves, tamman furnaces, atchison furnaces, hot press equipment, pulse energizing pressure sintering equipment, hot isostatic pressing equipment, pressurized atmosphere furnaces, heating
- a high frequency induction heating furnace, direct resistance heating, indirect resistance heating, direct combustion heating, radiant heat heating, current heating, or the like can be used. During the treatment, stirring may be performed as necessary.
- the atmosphere of the sintering treatment is not particularly limited, but under an N 2 atmosphere, an Ar atmosphere, a vacuum, an atmospheric flow, an N 2 flow, an Ar flow, an atmospheric pressure, or an N 2 pressure , Preferably under Ar pressure.
- degassing derived from the raw material can be promoted by heating under vacuum, which is effective in obtaining a sintered body with few voids.
- H 2 may be appropriately introduced into the atmospheric gas.
- the sintering treatment temperature is usually 300 ° C. or higher, preferably 400 ° C. or higher, more preferably 500 ° C. or higher, and usually 1900 ° C. or lower, preferably 1500 ° C. or lower. Preferably it is 1300 degrees C or less.
- the sintering temperature is usually 50 ° C. or lower, preferably 100 ° C. or lower, more preferably 150 ° C. or lower, based on the melting point of the fluoride inorganic binder used.
- the melting point of calcium fluoride (CaF 2 ) is 1418 ° C.
- the melting point of strontium fluoride (SrF 2 ) is 1477 ° C.
- the heating rate during firing is usually 10 ° C./min or less, preferably 2.5 ° C. or less, more preferably 1 ° C./min or less. If the temperature rise time is early, the sintering proceeds before the gas from the raw material escapes, which may cause a decrease in the degree of sintering. Instead of controlling the rate of temperature rise, it is also effective to raise the temperature after holding at a temperature lower than the firing top temperature, or to perform preliminary firing at a temperature lower than the firing top temperature as a degassing treatment step.
- the sintering treatment time is usually 0.1 hour or longer, preferably 0.5 hour or longer, more preferably 1 hour or longer, and usually 6 hours or shorter, preferably 5 hours or shorter, more preferably 4 hours or shorter. If the treatment temperature and time are smaller than this range, the organic components cannot be sufficiently removed. If the treatment temperature and time are larger than this range, the surface of the phosphor, such as oxidized, is denatured, leading to deterioration of the light emission characteristics.
- the heat history temperature conditions, the heating rate, the cooling rate, the heat treatment time, etc. are appropriately set. Further, after heat treatment in a relatively low temperature region, the temperature can be raised to a predetermined temperature.
- the reactor used for this process may be a batch type or a continuous type, and may be one or more.
- the molded body once obtained in the sintering process can be further sintered.
- the process used for sintering is not particularly limited, and includes a hot isostatic pressing apparatus.
- a sintering aid can be appropriately used.
- sintering aids for use in the sintering step for example, MgO, Y 2 O 3, CaO, Li 2 O, BaO, La 2 O 3, Sm 2 O 3, Sc 2 O 3, ZrO 2 , SiO 2 , MgAl 2 O 4 , LiF, NaF, BN, AlN, Si 3 N 4 , Mg, Zn, Ni, W, ZrB 2 , Ti, Mn, and the like. May be used.
- a sintered fluorescent substance is obtained by heating the mixed powder of the nitride fluorescent substance etc. which were obtained by the stirring and mixing process, and inorganic binder particle
- the furnace used for pressure press sintering is not particularly limited as long as the desired temperature and pressure can be achieved.
- hot press equipment pulse energization pressure sintering equipment, hot isostatic pressing equipment, heating method, high frequency induction heating furnace, direct resistance heating, indirect resistance heating, direct combustion heating, radiant heat heating, current heating Etc.
- heating method high frequency induction heating furnace, direct resistance heating, indirect resistance heating, direct combustion heating, radiant heat heating, current heating Etc.
- the atmosphere of the pressure press sintering treatment is not particularly limited, but N 2 atmosphere, Ar atmosphere, vacuum, air flow, N 2 flow, Ar flow, atmospheric pressure, N It is preferable to carry out under 2 pressure and Ar pressure. Further, H 2 may be appropriately introduced into the atmospheric gas.
- the sintering treatment temperature is usually 300 ° C. or higher, preferably 400 ° C. or higher, more preferably 500 ° C. or higher, and usually 1900 ° C. or lower, preferably 1500 ° C. or lower. Preferably it is 1300 degrees C or less, More preferably, it is 1000 degrees C or less.
- the sintering temperature should just be 50 degreeC or more lower than melting
- the melting point of calcium fluoride (CaF 2 ) is 1418 ° C.
- the melting point of strontium fluoride (SrF 2 ) is 1477 ° C.
- the sintering treatment time is usually 0.1 hour or longer, preferably 0.5 hour or longer, more preferably 1 hour or longer, and usually 6 hours or shorter, preferably 5 hours or shorter, more preferably 4 hours or shorter.
- the pressure pressing pressure is usually 1 MPa or more, preferably 5 MPa or more, more preferably 10 MPa or more, and usually 1000 MPa or less, preferably 800 MPa or less, more preferably 600 MPa or less. If the pressure at the time of molding is too low, a molded body cannot be obtained, and if the pressure is too high, the phosphor may be mechanically damaged and the light emission characteristics may be reduced.
- the heat history temperature condition, the heating rate, the cooling rate, the heat treatment time, etc. are appropriately set. Further, after heat treatment in a relatively low temperature region, the temperature can be raised to a predetermined temperature.
- the reactor used for this process may be a batch type or a continuous type, and may be one or more.
- a sintering aid can be appropriately used.
- the sintering aid used in the sintering step MgO, Y 2 O 3, CaO, Li 2 O, BaO, La 2 O 3, Sm 2 O 3, Sc 2 O 3, ZrO 2 , SiO 2, MgAl 2 O 4 , LiF, NaF, BN, AlN, Si 3 N 4, Mg, Zn, Ni, W, ZrB 2, Ti, Mn, and the like, by mixing two or more kinds of these You may use.
- the obtained sintered phosphor may be used as it is, but it is usually sliced at a predetermined thickness, and further processed to a predetermined thickness plate shape by grinding and polishing to obtain a plate-like sintered phosphor. .
- Grinding / polishing conditions are not particularly limited. For example, with a # 800 diamond grindstone, polishing is performed at a grindstone rotation speed of 80 rpm, a workpiece rotation speed of 80 rpm, and 50 g / cm 2 and processed into a plate shape.
- the lower limit of the final thickness of the sintered phosphor is usually 30 ⁇ m or more, preferably 50 ⁇ m or more, more preferably 100 ⁇ m or more, and the upper limit is usually 2000 ⁇ m or less, preferably 1000 ⁇ m or less, more preferably 800 ⁇ m or less, more Preferably it is 500 micrometers or less. If the thickness of the sintered phosphor plate is less than this range, the sintered phosphor plate is easily damaged.
- the unevenness may be appropriately formed by wet etching treatment, dry wet etching treatment or the like.
- the sintered phosphor of the present embodiment preferably further has the following characteristics.
- -Sintering degree As a method for confirming the sintering degree of the sintered phosphor of the present embodiment, the density ⁇ a by the Archimedes method is measured, and the theoretical density ⁇ theoretical of the sintered body is used, and ⁇ a / Calculated by ⁇ theoretical ⁇ 100.
- the theoretical density is the density when atoms in the material are ideally arranged.
- the degree of sintering of the sintered phosphor is usually 90% or more, preferably 95% or more, more preferably 99% or more. If the degree of sintering is within this range, the number of pores (voids) existing inside the sintered phosphor is reduced, and the light transmittance and light extraction efficiency (conversion efficiency) are improved. On the other hand, if the degree of sintering is below this range, light scattering is strong and the light extraction efficiency decreases. For this reason, the said range is preferable.
- the degree of sintering of the sintered phosphor can be adjusted to the above range by adjusting the sintering temperature and the sintering time.
- Absorptivity As a method for confirming the absorptivity of the sintered phosphor of the present embodiment, a method of measuring with an absorptiometer (UV-Vis) can be mentioned.
- the absorptivity of the sintered phosphor with respect to visible light of 500 nm or more is usually 10% or less, preferably 5.0% or less, more preferably 3.5% or less, and further preferably 1.5% or less.
- the absorptance is larger than 10%, the light emission efficiency (internal quantum efficiency) and the transmittance tend to be lowered, and thereby the light extraction efficiency (conversion efficiency) tends to be lowered. For this reason, the said range is preferable.
- the absorptance with respect to light of 500 nm or less is preferably higher, preferably 40% or more, more preferably 50% or more, and particularly preferably 60% or more.
- the absorption rate for light of 500 nm or less is high, light generated by the LED or laser of the light emitting device can be efficiently absorbed, and the amount of fluorescent light can be increased.
- the transmittance of the sintered phosphor is measured at a wavelength of 700 nm, and is usually 20% or more, preferably 25% or more, more preferably 30% or more, and further preferably 40% or more. If the transmittance is less than 20%, the amount of excitation light that passes through the sintered phosphor decreases, making it difficult to achieve the desired chromaticity and decreasing the light extraction efficiency (conversion efficiency).
- Correlated color temperature CCT, chromaticity coordinates CIE-x, y The correlated color temperature of the sintered phosphor of the present embodiment is calculated from the emission color including the transmitted light of the blue light obtained by irradiating the blue light with a peak wavelength of 450 nm emitted from the LED.
- the correlated color temperature of sintered phosphors used in general lighting devices and the like is normally 1900K or more and 5000K or less when excited with blue light having a wavelength of 450 nm, and 2700K, 3000K, 4000K, and 5000K lighting devices are common. Therefore, it is preferable to adjust to these color temperatures.
- An illuminating device having a low correlated color temperature such as 1900K has recently been used as illumination simulating candle light, and it is also preferable to adjust to this correlated color temperature.
- the higher the internal quantum efficiency of the sintered phosphor the more preferable, Preferably it is 60% or more, more preferably 65% or more, still more preferably 70% or more, still more preferably 75% or more, and particularly preferably 80% or more. If the internal quantum efficiency is low, the light extraction efficiency (conversion efficiency) tends to decrease.
- the present invention is a light emitting device including a sintered phosphor and a semiconductor light emitting element.
- the light emitting device of the present invention contains at least a blue semiconductor light emitting element (blue light emitting diode or blue semiconductor laser) and a sintered phosphor according to an embodiment of the present invention which is a wavelength conversion member that converts the wavelength of blue light. To do.
- the blue semiconductor light emitting element and the sintered phosphor may be in close contact with each other or may be separated from each other, and a transparent resin may be provided therebetween, or a space may be provided.
- a structure having a space between the semiconductor light emitting element and the sintered phosphor is preferable as shown in a schematic diagram in FIG.
- an embodiment in which the blue semiconductor light emitting element and the sintered phosphor are in close contact is also a preferred embodiment.
- the sintered phosphor and the blue semiconductor light emitting element are preferably bonded with an adhesive having high heat resistance and high heat conductivity in order to promote mutual heat conduction.
- a silicone resin adhesive is preferable as the adhesive having high heat resistance.
- an adhesive containing a filler (fine particles) for improving the thermal conductivity is preferable.
- the thickness of the adhesive is preferably as thin as possible, preferably 5 microns or less, and 2 microns or less. Is more preferable.
- a configuration in which the sintered phosphor and the blue semiconductor light emitting element are brought into close contact with each other by another structural device without using an adhesive is preferable from the viewpoint that the heat resistant temperature of the entire light emitting element can be increased.
- the reason is that when a silicone resin adhesive is used, it cannot be used beyond the heat resistance temperature of a silicone resin adhesive, which is generally said to be about 200 ° C., or even if it can be used, the durability is inferior. This is because it becomes.
- FIG. 4 is a schematic view of a light emitting device according to a specific embodiment of the present invention.
- the light emitting device 10 includes at least the blue semiconductor light emitting element 1 and the sintered phosphor 3 as its constituent members.
- the blue semiconductor light emitting element 1 emits excitation light for exciting the phosphor contained in the sintered phosphor 3.
- the blue semiconductor light emitting device 1 usually emits excitation light having a peak wavelength of 425 nm to 475 nm, and preferably emits excitation light having a peak wavelength of 430 nm to 470 nm.
- the number of blue semiconductor light emitting elements 1 can be appropriately set depending on the intensity of excitation light required by the apparatus.
- the violet semiconductor light emitting device usually emits excitation light having a peak wavelength of 390 nm to 425 nm, and preferably emits excitation light having a peak wavelength of 395 to 415 nm.
- an indium gallium nitride light emitting diode (LED) or an indium gallium nitride semiconductor laser is preferable.
- the light output (radiant flux) of the blue or purple semiconductor light emitting element is preferably 1.0 W or more, more preferably 2.0 W or more, and particularly preferably 3.0 W or more per 1 mm 2 of the light emitting area of the light emitting element.
- the blue semiconductor light emitting element 1 is mounted on the chip mounting surface 2a of the wiring board 2.
- a wiring pattern (not shown) for supplying electrodes to these blue semiconductor light emitting elements 1 is formed on the wiring substrate 2 to constitute an electric circuit.
- FIG. 4 it is displayed that the sintered phosphor 3 is placed on the wiring board 2, but this is not a limitation, and the wiring board 2 and the sintered phosphor 3 may be arranged via other members. Good.
- the wiring board 2 and the sintered phosphor 3 are arranged via the frame body 4.
- the frame body 4 may have a tapered shape in order to give light directivity.
- the frame 4 may be a reflective material.
- the wiring board 2 is preferably excellent in electrical insulation, has good heat dissipation, and preferably has a high reflectance, but on the chip mounting surface of the wiring board 2.
- a reflective plate having a high reflectance can be provided on the surface where the blue semiconductor light emitting element 1 does not exist, or on at least a part of the inner surface of another member connecting the wiring substrate 2 and the sintered phosphor 3.
- the sintered phosphor 3 converts the wavelength of part of incident light emitted from the blue or purple semiconductor light emitting element 1 and emits outgoing light having a wavelength different from that of the incident light.
- the sintered phosphor 3 contains a fluoride inorganic binder and a nitride phosphor.
- the sintered phosphor further includes one or more of another nitride phosphor, a garnet phosphor emitting yellow or green, an oxide phosphor emitting blue or green, and a nitride phosphor emitting red.
- the type can be selected in consideration of the intended emission color, color rendering, spectral shape, and the like.
- the light emitting device of the present invention is preferably a light emitting device that emits white light having a low color temperature.
- the color temperature is preferably 1800K or more and 5000K or less.
- emits white light is suitably provided in an illuminating device.
- ⁇ Lighting device ⁇ Another embodiment of the present invention is an illumination device including a light emitting device having the sintered phosphor. As described above, since a high total luminous flux is emitted from the light emitting device, a lighting fixture having a high total luminous flux can be obtained.
- the luminaire is preferably provided with a diffusing member that covers the sintered phosphor in the light emitting device so that the color of the sintered phosphor is not noticeable when the light is extinguished.
- Image display device ⁇ Another embodiment of the present invention is an image display device including a light emitting device having the sintered phosphor. As described above, the light emitting device of the present invention emits light having a particularly high proportion of red light. Therefore, an image display device with excellent color balance can be obtained by using this light emitting device as a backlight.
- a vehicular lamp / indicator comprising a light-emitting device having the sintered phosphor.
- This light-emitting device can be used as a vehicular lamp such as a high-power headlamp, a vehicle width lamp, a position light, a small lamp, a fog lamp, a daytime running light, and an interior lighting.
- a brake light stop
- Lamp and a direction indicator (turn lamp).
- ⁇ Measuring method ⁇ [Luminescent characteristics] The sample was packed in a copper sample holder, and the emission spectrum was measured using MCPD7000 (Otsuka Electronics Co., Ltd.). The emission intensity of each wavelength was measured with a spectrum measuring device in the wavelength range of 380 nm to 800 nm under the condition of excitation light of 455 nm, and an emission spectrum was obtained.
- the chromaticity coordinates are the XYZ color system defined by JIS Z8701 (1999) according to JIS Z8724 (1997) from the data in the wavelength region of 480 nm to 780 nm of the emission spectrum obtained by the above method.
- the chromaticity coordinate values x and y were calculated.
- the relative luminance is expressed as a relative value when the Y value in the XYZ color system when Example 5 is excited at a wavelength of 455 nm is set to 100.
- the emission peak wavelength hereinafter sometimes referred to as “peak wavelength”
- peak wavelength the half width of the emission peak were read from the obtained emission spectrum.
- Examples 2 to 5 The phosphors of Examples 2 to 5 were obtained in the same manner as Example 1 except that the charged composition ratio was changed as shown in Table 1.
- Comparative Example 2 In Comparative Example 1, a phosphor of Comparative Example 2 was obtained in the same manner as Comparative Example 1, except that after dehydration and drying, steam treatment was performed in an autoclave at 135 ° C. and 0.33 MPa for 20 hours.
- Comparative Example 3 In Comparative Example 1, mol amount of mixing the exception that the Y 2 O 3 to La 2 O 3 is unchanged, to obtain a phosphor of Comparative Example 3 in the same manner as in Comparative Example 1.
- Example 6 The phosphor of Example 6 was obtained in the same manner as Example 5 except that the top temperature holding time during firing was changed from 8 hours to 16 hours.
- Comparative Example 4 (Comparative Example 4)
- a phosphor of Comparative Example 4 was obtained in the same manner as Comparative Example 1 except that the time was changed from 8 hours to 23 hours.
- Table 2 shows the lattice constants and emission characteristics (chromaticity coordinate values x, y, emission peak wavelength) calculated from the results of XRD measurement for the phosphors of Examples 1 to 8 and Comparative Examples 1 to 5.
- the LYSN phosphor of the present invention has an emission peak in a longer wavelength region than the conventional LYSN phosphor. Therefore, the light emitting device including the phosphor according to the present invention has a low color temperature even when the red phosphor is not used.
- FIG. 1 shows emission spectrum diagrams of the phosphors of Example 8 and Comparative Example 1.
- Table 3 shows the results of measuring the emission luminance of the phosphors of Examples 5 and 6 and Comparative Examples 4 and 5, which have close emission chromaticities.
- the light emission luminance is expressed as a relative value with the light emission luminance of the phosphor of Example 5 as 100.
- the phosphors of Examples 5 and 6 have an emission luminance improved by 8 points or more as compared with the phosphors of Comparative Examples 4 and 5 having w values outside the range. This is presumably because the phosphor of the present invention hardly generates a Si-rich heterogeneous phase such as LaSi 3 N 5 and has little emission inhibition due to the heterogeneous phase.
- Table 4 shows the composition analysis results in the ICP-OES analysis of samples other than Example 6.
- Comparative Examples 4 and 5 having low luminance have a Si content higher than that of Example 5, and as a result, from the stoichiometric ratio of the total amount of La, Ce and Y from 3.00. You can see that it is below. From this, it is surmised that Comparative Examples 4 and 5 with a small amount of La are contained Si-rich components different from La 3 Si 6 N 11 .
- Example 5 and Comparative Examples 4 and 5 are shown in FIG. As shown in FIG. 2, in Comparative Examples 4 and 5, a large amount of LaSi 3 N 5 was confirmed, which resulted in a composition deviating greatly from the stoichiometric ratio, and it is considered that the powder brightness was lowered.
- Table 5 shows the same measurement results of YAG phosphor BY-102 / J (Mitsubishi Chemical Corporation) as Reference Example 1 and BY-102 / Q (Mitsubishi Chemical Corporation) as Reference Example 2.
- Table 5 relative emission peak intensities at 100 ° C., 200 ° C., and 300 ° C. when the emission peak intensity at 25 ° C. is defined as 100% are shown.
- Example 2 has better emission peak intensity maintenance ratio at high temperature than Reference Example 1, and Examples 5 and 8 have a higher emission peak intensity maintenance ratio than Reference Example 2, and compared with YAG of the same color or longer wave emission. However, it can be seen that the emission peak is maintained.
- the LYSN phosphor of the present invention maintains the emission peak intensity predominantly in any emission chromaticity range that can be realized by the present invention, and the temperature quenching is small, compared with the YAG phosphor widely used in LEDs. .
- the phosphor of the present invention can maintain high performance even with high-power LEDs that are exposed to high temperatures. That is, the light emitting device including the phosphor according to the present invention is of high quality in which color misregistration or the like hardly occurs.
- a light emitting device was fabricated using the phosphors of Comparative Example 1 and Examples 1, 3, 5 to 8, and the color temperature thereof was confirmed.
- Table 6 shows the chromaticity coordinate values x and y of the manufactured light emitting device and the reproduced color temperature.
- the light emitting device including the phosphor of the present invention achieves a low color temperature of 5000 K or less without using other red and green phosphors.
- the degree of sintering, phosphor emission characteristics, phosphor lattice constant, optical characteristics, and transmittance were measured as follows.
- lattice constants a and c were determined by pattern fitting. Pattern fitting was performed based on the crystal structure of La 3 Si 6 N 11 (space group P4bm).
- a light emitting device capable of obtaining the light emission of the sintered phosphor by irradiating the blue light emitted from the LED chip (peak wavelength 454 nm) was produced.
- the emission spectrum emitted from the apparatus is observed using a 40 inch integrating sphere (manufactured by LabSphere) and a spectroscope MCPD9000 (manufactured by Otsuka Electronics Co., Ltd.). Coordinates and luminous flux were measured. Further, the conversion efficiency (lm / W) was calculated for each intensity from the luminous flux (lumen) and the radiant flux (W) of the LED chip.
- the excitation wavelength was set to 700 nm, and the transmittance of the sintered phosphor at the excitation wavelength of 700 nm was measured from the reflection and transmission spectra when irradiated to the sintered phosphor.
- the excitation wavelength was changed to 450 nm, and the internal quantum efficiency and the absorption rate at the excitation wavelength of 450 nm of the sintered phosphor were measured from the reflection and transmission spectra when the sintered phosphor was irradiated.
- Spectra Corp. used a spectral light source, and reflection and transmission spectra were observed with a 20 inch integrating sphere LMS-200 (LabSphere) and a spectroscope Solid LambdaUV-Vis (Carl Zeiss).
- Example 15 [Manufacture of LYSN phosphor] LYSN phosphor 1 was obtained in the same manner as in Example 8. The median particle size of this phosphor was 30 ⁇ m.
- Table 7 shows the results of calculating the lattice constants a and c based on this data.
- the measurement results of the light emission characteristics are also shown in Table 7.
- the obtained pellets were vacuum laminated and introduced into a cold isostatic pressing (CIP) apparatus (Nikkiso Rubber Press) and pressurized at 300 MPa for 1 minute. Then, it introduce
- CIP cold isostatic pressing
- the obtained sintered phosphor with a diameter of 18 mm and a thickness of 3 mm is cut with a diamond cutter to a thickness of about 0.5 mm, and further, grinder grinding is used to obtain a sintered phosphor with a diameter of 18 mm and a thickness of 0.2 mm. Produced.
- Example 16 The LYSN phosphor 2 was obtained in the same manner as in Example 2. The median particle size of this phosphor was 20 ⁇ m. The powder X-ray diffraction pattern of this phosphor is shown in FIG. Table 7 shows the results of calculating the lattice constants a and c based on this data. The measurement results of the light emission characteristics are also shown in Table 7.
- a sintered phosphor was obtained according to the procedure of [Production of sintered phosphor] in Example 15. However, the addition amount of the phosphor was 0.2 g so that the phosphor was 6% by volume with respect to 2.0 g of CaF 2 .
- the temperature was raised to 1100 ° C. in an Ar atmosphere by a hot isostatic press (HIP) and held at 100 MPa for 1 hour.
- HIP hot isostatic press
- the sintered phosphor of this embodiment has a high sintered density and transmittance. Furthermore, the sintered body of the present invention has a high quantum yield and absorption rate of excitation light (450 nm).
- the light-emitting device using the sintered phosphor of the present embodiment has high luminous efficiency, high luminance, and can emit light in a low color temperature range with many red components. It is.
- Example 17 A light emitting device having a correlated color temperature of 6500 K manufactured using a blue LED having a peak wavelength of 454 nm and the LYSN phosphor 2 and the LSN phosphor (La 3 Si 6 N 11 : Ce) BY-201 / F (manufactured by Mitsubishi Chemical Corporation). The emission spectrum was calculated by simulation and is shown in FIG. Table 11 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- Example 17 is the same as Example 17 except that YAG phosphor (Y 3 Al 5 O 12 : Ce) BY-102 / H (manufactured by Mitsubishi Chemical Corporation) was used instead of LSN phosphor BY-201 / F. Similarly, simulation was performed to obtain a spectrum of a light emitting device having a correlated color temperature of 6500K. The result is shown in FIG. Table 11 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- the light emitting device of the present invention is a highly efficient white light emitting device having a correlated color temperature of 6500K.
- a sintered phosphor containing two types of phosphors is used, so that the influence of variation among phosphors in lots is offset by adjusting the blending ratio of the two types of phosphors during mass production. This is a light-emitting device that can be easily manufactured.
- Example 19 A blue LED having a peak wavelength of 454 nm, and the LYSN phosphor 2 and a SCASN phosphor ((Sr, Ca) AlSiN 3 : Eu) BR-102 / L (manufactured by Mitsubishi Chemical Corporation) as the nitride red phosphor were produced.
- the emission spectrum of the light emitting device having a correlated color temperature of 3000 K is calculated by simulation and shown in FIG. Table 12 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- Example 19 In Example 19, except that the nitride phosphor shown in Table 12 was used instead of BR-102 / L as a nitride red phosphor, a simulation was performed in the same manner as in Example 19 to obtain an emission spectrum of the light emitting device. It was. The obtained emission spectrum is shown in FIG. Table 12 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- Table 12 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- Example 23 to 26 A simulation was performed in the same manner as in Example 19 except that the correlated color temperature of the light emitting device was set to 4000 K, and an emission spectrum of the light emitting device was obtained. The obtained emission spectrum is shown in FIG. Table 13 shows the chromaticity coordinates x and y, the color rendering index (Ra and R1 to R15), the correlated color temperature, and the deviation D UV of the light emitting device.
- the light-emitting device of the present invention is a light-emitting device that emits light having a low color temperature of a correlated color temperature of 3000K. Since a fluoride inorganic binder having a high thermal conductivity is used, it is expected that the luminous efficiency is unlikely to decrease even when the output of the blue LED that excites the sintered phosphor is increased. Also, the color rendering properties can be adjusted by changing the type of nitride red phosphor, and the conversion efficiency can be improved by keeping the color rendering properties low, so that the desired conversion efficiency, luminous flux, and color rendering properties are exhibited. A light emitting device can be obtained.
- the light-emitting device of the present invention is a light-emitting device that emits light having a low color temperature of a correlated color temperature of 4000K. Since a fluoride inorganic binder having a high thermal conductivity is used, it is expected that the luminous efficiency is unlikely to decrease even when the output of the blue LED that excites the sintered phosphor is increased. Also, the color rendering properties can be adjusted by changing the type of nitride red phosphor, and the conversion efficiency can be improved by keeping the color rendering properties low, so that the desired conversion efficiency, luminous flux, and color rendering properties are exhibited. A light emitting device can be obtained.
- Example 27 Using the mixed powder of LYSN phosphor 2 and LSN phosphor (La 3 Si 6 N 11 : Ce) BY-201 / G (manufactured by Mitsubishi Chemical Corporation) in Example 16 in a volume ratio of 92: 8, the same as in Example 16 A sintered phosphor was obtained by the following procedure. Thereafter, the processing and evaluation were performed in the same manner as in Example 15 except that the thickness during processing was 0.24 mm, and the evaluation results were similarly obtained. The obtained results are shown in FIG.
- Example 28 Using a mixed powder of LYSN phosphor 2 of Example 16 and YAG phosphor BY-102 / H (manufactured by Mitsubishi Chemical Corporation) in a volume ratio of 90:10, a sintered phosphor was obtained by the same procedure as Example 16. . Thereafter, the processing and evaluation were performed in the same manner as in Example 15 except that the thickness during processing was 0.24 mm, and the evaluation results were similarly obtained. The obtained results are shown in FIG.
Abstract
Description
1.正方晶の結晶相を含む蛍光体であって、
該結晶相が、M元素、La、A元素、Si、Nを含み、かつ
下記式[I]および[II]を満たし、さらに、
格子定数aが、10.104Å以上、10.154Å以下であることを特徴とする、蛍光体。
0.10≦x/(w+x)≦0.50 [I]
2.80≦w+x+z≦3.20 [II]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[I]および[II]中、
wは、Siのモル比を6とした時のLa元素の含有量を表し、
xは、Siのモル比を6とした時のA元素の含有量を表し、
zは、Siのモル比を6とした時のM元素の含有量を表す。)
2.正方晶の結晶相を含む蛍光体であり
該結晶相が、M元素、La、A元素、Si、Nを含み、かつ
格子定数aが、10.104Å以上、10.154Å以下である蛍光体であって、
原料に含まれる各元素の比率が下記式[III]および[IV]を満たすように原料を調製し、焼成することによって得られることを特徴とする、蛍光体。
0.1≦x2/(w2+x2)≦0.5 [III]
2.85≦w2≦3.2 [IV]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[III]および[IV]中、
w2は、Siのモル比を6とした時のLa元素の仕込み量を表し、
x2は、Siのモル比を6とした時のA元素の仕込み量を表す。)
3.前記結晶相が、下記式(1)で表される組成を有することを特徴とする、前記1または2に記載の蛍光体。
LawAxSi6NyMz (1)
(式(1)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w、x、y、zは、各々独立に、下記式を満たす値である。
wは、1.50≦w≦2.7
xは、0.2≦x≦1.5
yは、8.0≦y≦14.0
zは、0.05≦z≦1.0)
4.300nm以上、460nm以下の波長を有する励起光を照射することにより、546nm以上、570nm以下の範囲に発光ピーク波長を有することを特徴とする、前記1~3のいずれか1に記載の蛍光体。
5.第1の発光体と、該第1の発光体からの光の照射によって可視光を発する第2の発光体とを備え、
該第2の発光体が、前記1~4のいずれか1に記載の窒化物蛍光体の1種以上を、第1の蛍光体として含むことを特徴とする、発光装置。
6.前記5に記載の発光装置を光源として含むことを特徴とする、照明装置。
7.前記5に記載の発光装置を光源として含むことを特徴とする、画像表示装置。
8.結晶相が、M元素、La、A元素、Si、Nを含み、かつ
格子定数aが、10.104Å以上、10.154Å以下である蛍光体の製造方法であって、
M源、La源、A源、Si源を原料として、各元素の比率が下記式[III]および[IV]を満たすように原料を調製し、焼成することを特徴とする蛍光体の製造方法。
0.1≦x2/(w2+x2)≦0.5 [III]
2.85≦w2≦3.2 [IV]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[III]および[IV]中、
w2は、Siのモル比を6とした時のLa元素の仕込み量を表し、
x2は、Siのモル比を6とした時のA元素の仕込み量を表す。)
9.原料中に含まれる金属元素の組成が下記式(2)で表される組成を満たすように仕込み量を調整することを特徴とする、前記8に記載の蛍光体の製造方法。
Law2Ax2Si6Ny2Mz2 (2)
(式(2)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w2は前記式[IV]を満たす値であり、
x2、y2、z2は、各々独立に、下記式を満たす値である。
x2は、0.2≦x2≦1.5
y2は、8.0≦y2≦14.0
z2は、0.05≦z2≦1.0)
本発明の蛍光体は、正方晶の結晶相を含み、
該結晶相が、M元素、La、A元素、Si、Nを含み、かつ
下記式[I]および[II]を満たし、さらに、
格子定数aが、10.104Å以上、10.154Å以下であることを特徴とする。
2.80≦w+x+z≦3.20 [II]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[I]および[II]中、
wは、Siのモル比を6とした時のLa元素の含有量を表し、
xは、Siのモル比を6とした時のA元素の含有量を表し、
zは、Siのモル比を6とした時のM元素の含有量を表す。)
なお、本明細書において、Siのモル比を6とした時の各元素の含有量はモル比で示される。
2.85≦w2≦3.2 [IV]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[III]および[IV]中、
w2は、Siのモル比を6とした時のLa元素の仕込み量を表し、
x2は、Siのモル比を6とした時のA元素の仕込み量を表す。)
なお、本明細書において、Siのモル比を6とした時の各元素の仕込み量、すなわち、原料に含まれる金属元素の組成はモル比で示される。
Laは、ランタンを表す。
前記式[I]におけるx/(w+x)は、Siのモル比を6とした時、好ましくは0.11以上0.45以下であり、さらに好ましくは0.12以上0.40以下である。また、前記式[II]におけるw+x+zは、Siのモル比を6とした時、好ましくは2.85以上3.15以下であり、さらに好ましくは2.90以上3.10以下である。
本発明の蛍光体は下記式(1)で表わされる組成を有する結晶相を含むことが好ましい。
(式(1)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w、x、y、zは、各々独立に、下記式を満たす値である。
wは、1.50≦w≦2.7
xは、0.2≦x≦1.5
yは、8.0≦y≦14.0
zは、0.05≦z≦1.0)
式(1)におけるwは、Laの含有量を表し、前記式[I]および[II]におけるものと同義である。その範囲および好ましい態様も同様である。
なお、上述の各元素の含有量はモル比で示される。
本発明の蛍光体は、La3Si6N11の組成式で報告されている正方晶の結晶構造をとり、組成式にてLaの位置にLa及びA元素、M元素が入る。このような元素置換により基本骨格構造は保たれながら格子定数、原子座標が異なる結晶となる。
参考文献1[Acta Crystallographica.Section E,vol.70,i23ページ(2014)]によると、La3Si6N11は正方晶で、P4bmの空間群をもつ結晶であり、そのa軸の格子定数(格子定数a)は10.1988Å、c軸の格子定数(格子定数c)は4.84153Åである。
本発明の蛍光体における格子定数は、下記の通りである。
本発明の構成とすることで、従来のLYSN蛍光体よりも長波長領域に発光ピークを有するLYSN蛍光体が得られるとの効果を奏する理由について下記の通り推測する。
[発光色]
本発明の蛍光体の発光色は、化学組成等を調整することにより、波長300nm~460nmといった近紫外領域~青色領域の光で励起され、青緑色、緑色、黄緑色、黄色、橙色、赤色等、所望の発光色とすることができる。
本発明の蛍光体は、波長300nm以上、460nm以下の光で励起した場合における発光スペクトルを測定した場合に、以下の特性を有することが好ましい。本発明の蛍光体は、上述の発光スペクトルにおけるピーク波長が、通常546nm以上、好ましくは550nm以上、また、通常570nm以下、好ましくは565nm以下である。上記範囲内であると、得られる蛍光体において、良好な緑色ないし黄色を呈する点で好ましい。
本発明の蛍光体は、上述の発光スペクトルにおける発光ピークの半値幅が、通常130nm以下、好ましくは125nm以下、より好ましくは120nm以下、また通常30nm以上、好ましくは40nm以上、より好ましくは60nm以上である。
本発明の蛍光体は、通常350nm以上、好ましくは360nm以上、より好ましくは370nm以上、また、通常480nm以下、好ましくは470nm以下、より好ましくは460nm以下の波長範囲に励起ピークを有する。即ち、近紫外から青色領域の光で励起される。
本発明の蛍光体の製造方法は、本発明の蛍光体及び効果が得られるものであれば、特に制限はないが、例えば、前記式[III]および[IV]を満たすように原料を調製し焼成する方法が挙げられ、好ましくは、蛍光体の結晶相が前記式(1)の組成を満たすように仕込み量を調整する方法、および原料中に含まれる金属元素の組成が下記式(2)で表される組成を満たすように仕込み量を調整する方法が挙げられる。
(式(2)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w2は前記式[IV]を満たす値であり、
x2、y2、z2は、各々独立に、下記式を満たす値である。
x2は、0.2≦x2≦1.5
y2は、8.0≦y2≦14.0
z2は、0.05≦z2≦1.0)
なお、上述の各元素の含有量はモル比で示される。
本発明に用いられる原料(La源、A源、Si源、M源)としては、例えば、蛍光体の母体の構成元素であるLa、A元素、Si、必要に応じ発光波長等の調整のために添加する付活元素M、を含む金属、合金または化合物が挙げられる。
蛍光体製造用合金を使用する場合には、含有される金属元素の組成が、前記式(2)で表される組成に一致していれば蛍光体製造用合金のみ、または必要に応じてフラックス(成長補助剤)を混合して焼成すればよい。
このようにして得られた原料混合物は、通常は坩堝またはトレイ等の容器に充填し、雰囲気制御が可能な加熱炉に納める。この際、容器の材質としては、金属化合物との反応性が低いものが好ましく、例えば、窒化ホウ素、窒化珪素、炭素、窒化アルミニウム、モリブデン、タングステン等が挙げられる。
本発明における製造方法においては、上述した工程以外にも、必要に応じてその他の工程を行ってもよい。例えば、上述の焼成工程後、必要に応じて粉砕工程、洗浄工程、分級工程、表面処理工程、乾燥工程などを行なってもよい。
粉砕工程には、例えば、ハンマーミル、ロールミル、ボールミル、ジェットミル、リボンブレンダー、V型ブレンダー若しくはヘンシェルミキサー等の粉砕機、または乳鉢と乳棒を用いる粉砕などが使用できる。
洗浄工程は、本発明の効果を損なわない限り特に制限はなく、例えば、脱イオン水等の水、エタノール等の有機溶剤またはアンモニア水等のアルカリ性水溶液などで蛍光体表面を行うことができる。
分級工程は、例えば、水篩または各種の気流分級機または振動篩など各種の分級機を用いることにより行うことができる。中でも、ナイロンメッシュによる乾式分級を用いると、体積平均径10μm程度の分散性に優れた蛍光体を得ることができる。また、ナイロンメッシュによる乾式分級と、水簸処理とを組み合わせて用いると、体積メジアン径20μm程度の分散性の良い蛍光体を得ることができる。
前記洗浄を終了した蛍光体を、100℃~200℃程度で乾燥させる。必要に応じて乾燥凝集を防ぐ程度の分散処理(例えばメッシュパスなど)を行ってもよい。
本発明の蛍光体を用いて発光装置を製造する際には、耐湿性等の耐候性を一層向上させるために、又は後述する発光装置の蛍光体含有部における樹脂に対する分散性を向上させるために、必要に応じて、蛍光体の表面を異なる物質で一部被覆する等の表面処理を行ってもよい。
本発明の蛍光体は、液体媒体と混合して用いてもよい。特に、本発明の蛍光体を発光装置等の用途に使用する場合には、これを液体媒体中に分散させた形態で用いることが好ましい。本発明の蛍光体を液体媒体中に分散させたものを、適宜、「本発明に係る蛍光体含有組成物」などと呼ぶものとする。
本発明に係る蛍光体含有組成物に含有させる本発明の蛍光体の種類に制限は無く、上述したものから任意に選択することができる。また、本発明に係る蛍光体含有組成物に含有させる本発明の蛍光体は、1種のみであってもよく、2種以上を任意の組み合わせ及び比率で併用してもよい。更に、本発明に係る蛍光体含有組成物には、本発明の効果を著しく損なわない限り、本発明の蛍光体以外の蛍光体を含有させてもよい。
本発明に係る蛍光体含有組成物に使用される液体媒体としては、該蛍光体の性能を目的の範囲で損なわない限りにおいて特に限定されない。例えば、所望の使用条件下において液状の性質を示し、本発明の蛍光体を好適に分散させるとともに、好ましくない反応を生じないものであれば、任意の無機系材料及び/又は有機系材料が使用でき、例えば、シリコーン樹脂、エポキシ樹脂、ポリイミドシリコーン樹脂などが挙げられる。
本発明に係る蛍光体含有組成物中の蛍光体及び液体媒体の含有率は、本実施態様の効果を著しく損なわない限り任意であるが、液体媒体については、本発明に係る蛍光体含有組成物全体に対して、通常50重量%以上、好ましくは75重量%以上であり、通常99重量%以下、好ましくは95重量%以下である。
なお、本発明に係る蛍光体含有組成物には、本発明の効果を著しく損なわない限り、蛍光体及び液体媒体以外に、その他の成分を含有させてもよい。また、その他の成分は、1種のみを用いてもよく、2種以上を任意の組み合わせ及び比率で併用してもよい。
本発明の発光装置は、第1の発光体(励起光源)と、当該第1の発光体からの光の照射によって可視光を発する第2の発光体とを含む発光装置であって、該第2の発光体は本発明の蛍光体を含有する。ここで、本発明の蛍光体は、何れか1種を単独で使用してもよく、2種以上を任意の組み合わせ及び比率で併用してもよい。
本発明の発光装置は、本発明の蛍光体に加えて、更に546nm以上570nm以下の波長範囲に発光ピークを有する黄色蛍光体を含有していてもよい。
ガーネット系蛍光体としては、例えば、(Y,Gd,Lu,Tb,La)3(Al,Ga)5O12:(Ce,Eu,Nd)、
オルソシリケートとしては、例えば、(Ba,Sr,Ca,Mg)2SiO4:(Eu,Ce)、
(酸)窒化物蛍光体としては、例えば、(Ba,Ca,Mg)Si2O2N2:Eu(SION系蛍光体)、(Li,Ca)2(Si,Al)12(O,N)16:(Ce,Eu)(α-サイアロン蛍光体)、(Ca,Sr)AlSi4(O,N)7:(Ce,Eu)(1147蛍光体)、(La,Ca)3(Al,Si)6N11:Ce(LSN蛍光体)
などが挙げられる。
本発明の発光装置は、更に赤色蛍光体を含有していてもよい。赤色蛍光体としては、例えば、下記の蛍光体が好適に用いられる。
硫化物蛍光体としては、例えば、(Sr,Ca)S:Eu(CAS蛍光体)、La2O2S:Eu(LOS蛍光体)、
ガーネット系蛍光体としては、例えば、(Y,Lu,Gd,Tb)3Mg2AlSi2O12:Ce、
ナノ粒子としては、例えば、CdSe、
窒化物または酸窒化物蛍光体としては、例えば、(Sr,Ca)AlSiN3:Eu(S/CASN蛍光体)、(CaAlSiN3)1-x・(SiO2N2)x:Eu(CASON蛍光体)、(La,Ca)3(Al,Si)6N11:Eu(LSN蛍光体)、(Ca,Sr,Ba)2Si5(N,O)8:Eu(258蛍光体)、(Sr,Ca)Al1+xSi4-xOxN7-x:Eu(1147蛍光体)、Mx(Si,Al)12(O,N)16:Eu(Mは、Ca、Srなど)(αサイアロン蛍光体)、Li(Sr,Ba)Al3N4:Eu(上記のxは、いずれも0<x<1)
などが挙げられる。
本発明の発光装置は、更に緑色蛍光体を含有していてもよい。本発明における緑色蛍光体は、発光ピーク波長が510~545nmである蛍光体であり、例えば、下記の蛍光体が好適に用いられる。
シリケート系蛍光体としては、例えば、(Ba,Sr,Ca,Mg)3SiO10:(Eu,Ce)、(Ba,Sr,Ca,Mg)2SiO4:(Ce,Eu)(BSS蛍光体)、
酸化物蛍光体としては、例えば、(Ca,Sr,Ba,Mg)(Sc,Zn)2O4:(Ce,Eu)(CASO蛍光体)、
(酸)窒化物蛍光体としては、例えば、(Ba,Sr,Ca,Mg)Si2O2N2:(Eu,Ce)、Si6-zAlzOzN8-z:(Eu,Ce)(β-サイアロン蛍光体)(0<z≦1)、(Ba,Sr,Ca,Mg,La)3(Si,Al)6O12N2:(Eu,Ce)(BSON蛍光体)、(La,Ca)3(Al,Si)6N11:Ce(LSN蛍光体)
アルミネート蛍光体としては、例えば、(Ba,Sr,Ca,Mg)2Al10O17:(Eu,Mn)(GBAM系蛍光体)
などが挙げられる。
本発明の発光装置は、第1の発光体(励起光源)を有し、且つ、第2の発光体として少なくとも本発明の蛍光体を使用している他は、その構成は制限されず、公知の装置構成を任意にとることが可能である。
本発明の発光装置の用途は特に制限されず、通常の発光装置が用いられる各種の分野に使用することが可能であるが、色再現範囲が広く、且つ、演色性も高いことから、中でも照明装置や画像表示装置の光源として、とりわけ好適に用いられる。
本発明の照明装置は、本発明の発光装置を光源として備えることを特徴とする照明装置である。
本発明の画像表示装置は、本発明の発光装置を光源として備える画像表示装置である。本発明の発光装置を画像表示装置の光源として用いる場合、その画像表示装置の具体的構成に制限は無いが、カラーフィルターとともに用いることが好ましい。
〈1〉窒化物蛍光体及びフッ化物無機バインダを含む焼結蛍光体であって、
該窒化物蛍光体が、下記式[1]で表される結晶相を含む蛍光体であることを特徴とする、焼結蛍光体。
Law10Ax10Si6Ny10Mz10 [10]
(式中のM元素は付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
2.0≦w10≦4.0、
0<x10≦1.5、
8.0≦y10≦14.0、
0.05≦z10≦1.0)
〈2〉455nmの波長を有する励起光を照射することにより得られる前記式[1]で表される結晶相を含む蛍光体の蛍光が、CIE1931XYZ表色系で表した色度座標x、yで以下の式を満たすことを特徴とする、〈1〉に記載の焼結蛍光体。
0.43≦x≦0.50、
0.48≦y≦0.55
〈3〉該窒化物蛍光体の格子定数のaが10.104Å以上、10.185Å以下であることを特徴とする、〈1〉~〈3〉のいずれか1に記載の焼結蛍光体。
〈4〉更にその他の蛍光体を1種又は2種以上含有することを特徴とする〈1〉~〈3〉のいずれか1に記載の焼結蛍光体。
〈5〉〈1〉~〈4〉のいずれか1に記載の焼結蛍光体と、光源としてLED又は半導体レーザーとを備え、
前記焼結蛍光体は、前記光源の光の少なくとも一部を吸収して異なる波長を有する光を発することを特徴とする、発光装置。
〈6〉発光の相関色温度が5000K以下であることを特徴とする、〈5〉に記載の発光装置。
〈7〉〈5〉又は〈6〉に記載の発光装置を備えることを特徴とする、照明装置。
〈8〉〈5〉又は〈6〉に記載の発光装置を備えることを特徴とする、画像表示装置。
〈9〉〈5〉又は〈6〉に記載の発光装置を備えることを特徴とする、車両用灯具・表示灯。
本発明の実施形態に係る焼結蛍光体は、窒化物蛍光体、及びフッ化物無機バインダを含み、該窒化物蛍光体が前記式[10]で表される結晶相を含む蛍光体(以下、「式[10]蛍光体」と称する場合がある)である。
本発明における焼結蛍光体は、式[10]蛍光体を含む窒化物蛍光体及びフッ化物無機バインダから構成された複合体であれば特に制限はないが、好ましくは、窒化物蛍光体がフッ化物無機バインダ中に分散された状態であり、窒化物蛍光体とフッ化物無機バインダが物理的及び/または化学的な結合によって、一体化された複合体である。イオン半径の異なる窒化物とフッ化物を組み合わせることで、焼結時の窒化物蛍光体とフッ化物無機バインダとの反応を抑制させ、高い内部量子効率を有する焼結蛍光体を得ることが可能である。
本発明の実施形態に係る焼結蛍光体において、窒化物蛍光体が存在することを確認するための手法としては、X線回折による窒化物蛍光体相の同定、エネルギー分散型X線分析装置による粒子の元素分析、蛍光X線による元素分析などが挙げられる。
Law10Ax10Si6Ny10Mz10 [10]
(式[10]中のM元素は付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
2.0≦w10≦4.0、
0<x10≦1.5、
8.0≦y10≦14.0、
0.05≦z10≦1.0である。)
なお、上述の各元素の含有量はモル比で示される。
式[10]蛍光体は、La3Si6N11の組成式で報告されている正方晶の結晶構造をとり、組成式にてLaの位置にLa及びA元素、M元素が入る。このような元素置換により基本骨格構造は保たれながら格子定数、原子座標が異なる結晶となる。
参考文献1[Acta Crystallographica.Section E,vol.70,i23ページ(2014)]によると、La3Si6N11は正方晶で、P4bmの空間群をもつ結晶であり、その格子定数a=10.1988Å。c=4.84153Åである。
[発光色]
式[10]蛍光体は、455nmの波長を有する励起光を照射する励起した時の発光が、CIE(国際照明委員会)1931XYZ表色系で表した色度座標x、yで、以下の式を満たすことが好ましい。
0.43≦x≦0.50、
0.48≦y≦0.55
なお、色度座標x、yの算出は、測定されたスペクトルから、蛍光体に吸収されなかった励起光を除いた蛍光体だけのスペクトルを用いて行う。
式[10]蛍光体は、波長300nm以上、460nm以下の光で励起した場合における発光スペクトルを測定した場合に、以下の特性を有することが好ましい。
式[10]蛍光体の体積メジアン径は、通常0.1μm以上、好ましくは0.5μm以上であり、また、通常35μm以下、好ましくは25μm以下の範囲である。上記範囲とすることで、輝度の低下が抑制され、また蛍光体粒子の凝集を抑制できるため好ましい。なお、体積メジアン径は、例えばコールターカウンター法で測定でき、代表的な装置としては、精密粒度分布測定装置マルチサイザー(ベックマンコールター社製)が挙げられる。
焼結蛍光体の全体積に対する式[10]蛍光体の体積分率は、通常1%以上、50%以下である。体積分率は、焼結蛍光体の大きさ、厚み、形状、表面粗さ、発光装置の構造などによって影響されるため、所望の発光色を得るために調整されるべきパラメータであるが、窒化物蛍光体の体積分率が低すぎると、十分な波長変換ができず、体積分率が高すぎると波長変換効率が低下したり、フッ化物無機バインダの含有率が低くなりすぎるために、適切な機械強度の焼結蛍光体を製造するのが難しくなる。
式[10]蛍光体の製造方法は、式[10]蛍光体及びその効果が得られるものであれば、特に制限はないが、以下に好ましい製法について説明する。
式[10]蛍光体の製造方法に用いられる原料(La源、A源、Si源、M源)の詳細は、前記発明1と同様である。
蛍光体製造用合金を使用する場合には、含有される金属元素の組成が、前記式[10]で表される組成に一致していれば蛍光体製造用合金のみ、または必要に応じてフラックス(成長補助剤)を混合して焼成すればよい。
このようにして得られた原料混合物の焼成工程および後処理工程の詳細は、前記発明1と同様である。
[フッ化物無機バインダ、およびフッ化物無機バインダ粒子]
本発明の実施形態に係る焼結蛍光体において、フッ化物無機バインダが存在することを確認するための手法としては、X線回折による無機バインダ相の同定、電子顕微鏡による焼結体表面あるいは断面構造の観察および元素分析、蛍光X線による元素分析などが挙げられる。
・粒径
フッ化物無機バインダ粒子は、その体積メジアン径が、通常0.01μm以上、好ましくは0.02μm以上、より好ましくは0.03μm以上、特に好ましくは0.05μm以上であり、また、通常15μm以下、好ましくは10μm以下、より好ましくは5μm以下、更に好ましくは3μm以下、特に好ましくは2μm以下である。
フッ化物無機バインダ粒子の純度を確認するための手法としては、誘導結合プラズマ発光分光分析(ICP-AES分析)、蛍光X線による元素定量分析などが挙げられる。
フッ化物無機バインダ粒子の屈折率を確認するための手法としては、フッ化物無機バインダ粒子からなる焼結体を鏡面研磨し、それを用いて最小偏角法、臨界角法、Vブロック法により測定する方法が挙げられる。
フッ化物無機バインダ粒子の熱伝導率を確認するための手法としては、フッ化物無機バインダ粒子からなる焼結体を作製し、それを用いて定常加熱法、レーザーフラッシュ法、周期加熱法により測定する方法が挙げられる。
フッ化物無機バインダ粒子は、その融点が低いことが好ましい。融点が低いフッ化物無機バインダ粒子を用いることで、焼結温度を低減させることが可能となり、窒化物蛍光体と無機バインダが反応することによる窒化物蛍光体の失活を抑制することができ、焼結蛍光体の内部量子効率の低下を抑制できる。具体的には、融点が1500℃以下であることが好ましく、1300℃以下であることがより好ましい。下限温度は特段限定されず、通常500℃以上である。
フッ化物無機バインダ粒子は、溶解度が20℃において、水100g当たり、0.05g以下であることが好ましい。
本実施形態の焼結蛍光体は、本発明の効果を損なわない範囲で、式[10]蛍光体以外のその他の蛍光体を含んでいてもよい。その他の蛍光体としては、(酸)窒化物蛍光体であってもよく酸化物蛍光体であってもよく、またその両方を含んでいてもよい。
本実施形態の焼結蛍光体に含まれていてもよい(酸)窒化物蛍光体は、下記のものが挙げられる。
次の一般式で表すことができるβサイアロン:Si6-z AlzOz N8-z:Eu(式中0<z<4.2)、αサイアロン、
次の一般式で表されるLSN;LnxSiyNn:Z(式中Lnは付活元素として用いる元素を除いた希土類元素である。Zは付活元素である。2.7≦x≦3.3、5.4≦y≦6.6、10≦n≦12を満たす。)
次の一般式で表されるCASN:CaAlSiN3:Eu、
次の一般式で表すことができるSCASN:(Ca,Sr,Ba,Mg)AlSiN3:Eu及び/又は(Ca,Sr,Ba)AlSi(N,O)3:Eu)、
次の一般式で表すことができるCASON:(CaAlSiN3)1-x(Si2N2O)x:Eu(式中0<x<0.5)、
次の一般式で表すことができるCaAlSi4N7:(Sr,Ca,Ba)1-yAl1+xSi4-xOxN7-x:Euy(式中、0≦x<4、0≦y<0.2)、
次の一般式で表すことができるSr2Si5N8:Eu、すなわち、(Sr,Ca,Ba)2AlxSi5-xOxN8-x:Eu(式中0≦x≦2)等の蛍光体が挙げられる。
本実施形態の焼結蛍光体に含まれていてもよい酸化物蛍光体としては、下記のものが挙げられる。
上述した窒化物蛍光体及びフッ化物無機バインダ粒子、又はガーネット系蛍光体、窒化物蛍光体、及びフッ化物無機バインダ粒子を主たる原料とし、これらの混合物を圧密・焼結することで、上記材料の複合体である焼結蛍光体を製造することができるが、製法についての制限は特にない。より好ましい製造方法を以下に記載する。
上述した窒化物蛍光体及びフッ化物無機バインダ粒子、又はガーネット系蛍光体、窒化物蛍光体、及びフッ化物無機バインダ粒子を主たる原料とし、これらの混合物を圧密・焼結することで、上記材料の複合体である焼結蛍光体を製造することができるが、製法についての制限は特にない。より好ましい製造方法を以下に記載する。
(工程1)窒化物蛍光体(又はガーネット系蛍光体及び窒化物蛍光体)と無機バインダ粒子を撹拌・混合し、加圧プレス成形し、成形体を焼結する工程
(工程2)窒化物蛍光体(又はガーネット系蛍光体及び窒化物蛍光体)と無機バインダ粒子を撹拌・混合し、加圧プレスと同時に焼結する工程
・撹拌・混合工程
最初に、窒化物蛍光体(又はガーネット系蛍光体及び窒化物蛍光体)と無機バインダ粒子を混合させ、窒化物蛍光体等と無機バインダ粒子の混合粉を得る。窒化物蛍光体等と無機バインダ粒子からなる焼結体全体を100%とした場合、フッ化物無機バインダの体積分率が、通常50%以上、好ましくは60%以上、より好ましくは70%以上であり、通常99%以下、好ましくは98%以下、より好ましくは97%以下となるよう、混合させる。
ここでは、一軸金型成形、冷間静水圧成形(CIP)を用いて、撹拌・混合工程で得られた混合粉をプレス成形し、目的の形状のグリーン体を得る。成形時の圧力は、通常1MPa以上、好ましくは5MPa以上、より好ましくは10MPa以上であり、通常1000MPa以下である。成形時の圧力が低すぎると、成形体を得ることができず、圧力が高すぎると、蛍光体に機械的ダメージを与え、発光特性を低下させる原因となりえる。
必要に応じ、有機バインダを用いて成形したグリーン体から、空気中で有機バインダ成分を焼き飛ばす脱脂を実施する。脱脂に使用する炉は所望の温度、圧力を実現できれば特段限定されない。
成形工程及び/又は脱脂工程を経て得られた成形体を焼結することにより、焼結蛍光体を得る。焼結に使用する工程は、所望の温度、圧力を実現できれば特段限定されない。例えば、シャトル炉、トンネル炉、リードハンマー炉、オートクレーブ等の反応槽、タンマン炉、アチソン炉、ホットプレス装置、パルス通電加圧焼結装置、熱間静水圧焼結装置、加圧雰囲気炉、加熱方式も、高周波誘導加熱炉、直接式抵抗加熱、間接式抵抗加熱、直接燃焼加熱、輻射熱加熱、通電加熱等を用いることができる。処理時には、必要に応じて攪拌を行なってもよい。
・撹拌・混合工程
工程1の撹拌・混合工程と同様に実施することができる。
撹拌・混合工程により得られた窒化物蛍光体等と無機バインダ粒子との混合粉を、加圧しながら加熱することにより、焼結蛍光体を得る。加圧プレス焼結に使用する炉は、所望の温度、圧力を実現できれば特段限定されない。
[焼結蛍光体の特性]
本実施形態の焼結蛍光体は、更に以下のような特性を持つことが好ましい。
・焼結度
本実施形態の焼結蛍光体の焼結度を確認するための手法としては、アルキメデス法による密度ρaを測定し、焼結体の理論密度ρtheoreticalを用いて、ρa/ρtheoretical×100により算出する。
本実施形態の焼結蛍光体の吸収率を確認するための手法としては、吸光光度計(UV-Vis)、により測定する方法が挙げられる。
本実施形態の焼結蛍光体の透過率を確認するための手法としては、積分球及び分光器により測定する方法が挙げられる。
本実施形態の焼結蛍光体の相関色温度は、LEDから発せられるピーク波長450nmの青色光を照射して得られる青色光の透過光を含めた発光色から算出する。
本実施形態の焼結蛍光体の内部量子効率(iQE)は、ピーク波長450nmの青色光を照射した際の焼結蛍光体が吸収した光子数nexと吸収した光子を変換した変換光の光子数nemからnem/nexとして算出される。波長が450nmの青色光で励起した時に放出される光の内部量子効率が通常40%以上である高輝度発光装置とするためには、焼結蛍光体の内部量子効率は高ければ高いほど好ましく、好ましくは60%以上、より好ましくは65%以上、さらに好ましくは70%以上、よりさらに好ましくは75%以上、特に好ましくは80%以上である。内部量子効率が低いと、光取り出し効率(変換効率)を低下させる傾向がある。
本発明の別の実施形態は、焼結蛍光体と半導体発光素子を備える発光装置である。本発明の発光装置は、少なくとも青色半導体発光素子(青色発光ダイオード、又は、青色半導体レーザー)と、青色光の波長を変換する波長変換部材である本発明の実施形態に係る焼結蛍光体を含有するものである。青色半導体発光素子と焼結蛍光体とは密着していても、離間していてもよく、その間に透明樹脂を備えていてもよく、空間を有していてもよい。図3に模式図として示す様に半導体発光素子と焼結蛍光体との間に空間を有する構造であることが好ましい。
本発明の別の実施形態は、上記焼結蛍光体を有する発光装置を備える照明装置である。上記のように、発光装置からは高い全光束が出射されるため、全光束の高い照明器具を得ることが出来る。照明器具は、消灯時に焼結蛍光体の色が目立たないように、発光装置中の焼結蛍光体を覆う拡散部材を配置することが好ましい。
本発明の別の実施形態は、上記焼結蛍光体を有する発光装置を備える画像表示装置である。上記のように、本発明の発光装置からは特に赤色光の割合の高い光が出射されるため、この発光装置をバックライトとして用いることにより色バランスのすぐれた画像表示装置が得られる。
本発明の別の実施形態は、上記焼結蛍光体を有する発光装置を備える車両用灯具・表示灯である。この発光装置は、高出力の前照灯(ヘッドライト)、車幅灯、ポジションライト、スモールランプ、フォグランプ、デイタイムランニングライト、室内照明などの車両用灯具として利用することができる。また、本実施形態の焼結蛍光体は、赤色光の割合の高い光が出射されるため、適宜フィルターやミラー等を組み合わせて利用することにより、車両用の尾灯(テールランプ)、制動灯(ストップランプ)、方向指示器(ターンランプ)に好適に利用できる。
[発光特性]
試料を銅製試料ホルダーに詰め、MCPD7000(大塚電子社製)を用いて発光スペクトルを測定した。励起光455nmの条件で、380nm以上800nm以下の波長範囲においてスペクトル測定装置により各波長の発光強度を測定し、発光スペクトルを得た。
粉末X線回折(XRD)は、粉末X線回折装置X’Pert PRO MPD(PANalytical社製)にて精密測定した。測定条件は、下記の通りである。
CuKα管球使用
X線出力=45KV,40mA
測定範囲 2θ=10°~150°
読み込み幅=0.008°
粉末X線回折によって得られた回折パターンのピーク位置とLYSNの空間群(P4bm)から、単位格子の精密化を行い、格子定数を算出した。
分光蛍光光度計F-7000(日立ハイテクサイエンス社製)と温度制御ユニットを利用して、25℃、100℃、200℃、300℃の各温度における発光ピーク強度を測定して、その維持率を比較した。
(実施例1)
La:Si=1:1(モル比)の合金、Si3N4、Y2O3、CeF3をLa:Y:Ce:Si=3.00:0.41:0.24:6.0(モル比)になるように秤量し、混合した。これらの操作は、酸素濃度1%以下の窒素雰囲気のグローブボックス内で行った。
仕込み組成比を表1に示すように変更した以外は、実施例1と同様にして実施例2~5の蛍光体を得た。
実施例1において、原料の調合比をLa:Y:Ce:Si=3.00:0.41:0.20:6.00(モル比)になるように秤量した他は、実施例1と同様にして比較例1の蛍光体を得た。
比較例1において、脱水、乾燥後に135℃、0.33MPaで20時間のオートクレーブでの蒸気処理を施した他は、比較例1と同様にして比較例2の蛍光体を得た。
比較例1において、混合するmol量は変化させずにY2O3をLa2O3に変更した他は、比較例1と同様にして比較例3の蛍光体を得た。
焼成時のトップ温度保持時間を8時間から16時間へと変更した他は、実施例5と同様にして実施例6の蛍光体を得た。
実施例5において、原料種をLa:Si=1:1(モル比)の合金、Si3N4、Y2O3、YF3、CeF3とし、YF3:Y2O3=1.00:3.62(モル比)とし、仕込み元素比をLa:Y:Ce:Si=2.90:0.45:0.35:6.00(モル比)とした他は、実施例5と同様にして実施例7の蛍光体を得た。
実施例8において、原料種をLa:Si=1:1(モル比)の合金、Si3N4、Y2O3、YF3、CeF3とし、YF3:Y2O3=1.00:1.81(モル比)とし、仕込み元素比をLa:Y:Ce:Si=2.90:0.50:0.66:6.00(モル比)とした他は、実施例5と同様にして実施例8の蛍光体を得た。
比較例1において、原料の調合比をLa:Y:Ce:Si=2.64:0.36:0.45:6.00(モル比)になるように秤量し、焼成時のトップ温度保持時間を8時間から23時間と変更した以外は、比較例1と同様にして比較例4の蛍光体を得た。
比較例4において、原料の調合比をLa:Y:Ce:Si=2.53:0.34:0.43:6.00(モル比)になるように秤量した他は、比較例4と同様にして比較例5の蛍光体を得た。
実施例1~8ならびに比較例1~5の蛍光体について、XRD測定の結果から算出した格子定数及び発光特性(色度座標値x、y、発光ピーク波長)を表2に示す。
比較例1および実施例1、3、5~8の蛍光体を用いて発光装置を作製してその色温度を確認した。
焼結度は、焼結蛍光体のアルキメデス法により測定した密度ρaを、理論密度ρtheoreticalで除することで算出した。
焼結度(%)=(ρa/ρtheoretical)×100
前記発明1と同様に測定した。
粉末X線回折(XRD)は、粉末X線回折装置X’Pert PRO MPD(PANalytical社製)にて精密測定した。測定条件は、下記の通りである。
CuKα管球使用
X線出力=45KV,40mA
走査範囲 2θ=10°~150°
読み込み幅=0.008°
LEDチップ(ピーク波長454nm)から発光させた青色光を照射することで焼結蛍光体の発光を得ることができる発光装置を作製した。その装置から出射される発光スペクトルを40inch積分球(LabSphere社製)および分光器MCPD9000(大塚電子社製)を用いて観測し、放射束0.26Wの光でパルス励起した際の色温度色度座標、光束(lumen)を計測した。さらに、光束(lumen)とLEDチップの放射束(W)から変換効率(lm/W)を各強度で算出した。
[LYSN蛍光体の製造]
実施例8と同様にしてLYSN蛍光体1を得た。この蛍光体のメジアン粒径は30μmであった。
焼結蛍光体のフッ化物無機バインダ材料として、CaF2粉末(白辰化学研究所、1μm以下の微粒子)を2.0g用い、上記のLYSN蛍光体1((La,Y)3Si6N11:Ce)を焼結体中の蛍光体濃度が8体積%となるように0.27gをそれぞれ秤量し、乳鉢による混合を実施した。これらの粉末をボール無のボールミル架台上での回転によって2時間乾式混合し、焼結用原料に供した。
得られた焼結蛍光体Φ18mm、厚さ3mmの焼結蛍光体から、ダイヤモンドカッターで厚み0.5mm程度に切断し、さらにグラインダー研削を用いて、Φ18mm、厚み0.2mmの焼結蛍光体を作製した。
実施例2と同様にして、LYSN蛍光体2を得た。この蛍光体のメジアン粒径は20μmであった。この蛍光体の粉末X線回折パターンを図6に示す。このデータを元に格子定数aおよびcを計算した結果を表7に示す。また発光特性の測定結果についても表7に示す。
ピーク波長454nmの青色LEDと、上記LYSN蛍光体2とLSN蛍光体(La3Si6N11:Ce)BY-201/F(三菱化学社製)を用いて作製した相関色温度6500Kの発光装置の発光スペクトルをシミュレーションにより算出し、図8に示す。発光装置の色度座標x、および、y、演色性評価数(Ra、および、R1~R15)、相関色温度、偏差DUVを表11に示す。
実施例17において、LSN蛍光体BY-201/Fの代わりにYAG蛍光体(Y3Al5O12:Ce)BY-102/H(三菱化学社製)を用いた他は、実施例17と同様にシミュレーションを行って相関色温度6500Kの発光装置のスペクトルを得た。この結果を図9に示す。発光装置の色度座標x、および、y、演色性評価数(Ra、および、R1~R15)、相関色温度、偏差DUVを表11に示す。
ピーク波長454nmの青色LEDと、上記LYSN蛍光体2と窒化物赤色蛍光体としてSCASN蛍光体((Sr,Ca)AlSiN3:Eu)BR-102/L(三菱化学社製)を用いて作製した相関色温度3000Kの発光装置の発光スペクトルをシミュレーションにより算出し、図10に示す。発光装置の色度座標x、および、y、演色性評価数(Ra、および、R1~R15)、相関色温度、偏差DUVを表12に示す。
実施例19において、窒化物赤色蛍光体をBR-102/Lの代わりに表12に示す窒化物蛍光体を用いた他は、実施例19と同様にシミュレーションをして発光装置の発光スペクトルを得た。得られた発光スペクトルを図10に示す。発光装置の色度座標x、および、y、演色性評価数(Ra、および、R1~R15)、相関色温度、偏差DUVを表12に示す。
発光装置の相関色温度を4000Kとしたことを除いて実施例19と同様にシミュレーションをして発光装置の発光スペクトルを得た。得られた発光スペクトルを図11に示す。発光装置の色度座標x、および、y、演色性評価数(Ra、および、R1~R15)、相関色温度、偏差DUVを表13に示す。
実施例16のLYSN蛍光体2とLSN蛍光体(La3Si6N11:Ce)BY-201/G(三菱化学社製)の体積比92:8の混合粉用いて、実施例16と同様の手順により焼結蛍光体を得た。加工時の厚みを0.24mmとする以外これ以降加工及び評価は実施例15と同様に行い、同様に評価結果を得た。得られた結果を図12および表14に示す。
実施例16のLYSN蛍光体2とYAG蛍光体BY-102/H(三菱化学社製)の体積比90:10の混合粉用いて、実施例16と同様の手順により焼結蛍光体を得た。加工時の厚みを0.24mmとする以外これ以降加工及び評価は実施例15と同様に行い、同様に評価結果を得た。得られた結果を図12および表14に示す。
Claims (9)
- 正方晶の結晶相を含む蛍光体であって、
該結晶相が、M元素、La、A元素、Si、Nを含み、かつ
下記式[I]および[II]を満たし、さらに、
格子定数aが、10.104Å以上、10.154Å以下であることを特徴とする、蛍光体。
0.10≦x/(w+x)≦0.50 [I]
2.80≦w+x+z≦3.20 [II]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[I]および[II]中、
wは、Siのモル比を6とした時のLa元素の含有量を表し、
xは、Siのモル比を6とした時のA元素の含有量を表し、
zは、Siのモル比を6とした時のM元素の含有量を表す。) - 正方晶の結晶相を含む蛍光体であり
該結晶相が、M元素、La、A元素、Si、Nを含み、かつ
格子定数aが、10.104Å以上、10.154Å以下である蛍光体であって、
原料に含まれる各元素の比率が下記式[III]および[IV]を満たすように原料を調製し、焼成することによって得られることを特徴とする、蛍光体。
0.1≦x2/(w2+x2)≦0.5 [III]
2.85≦w2≦3.2 [IV]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[III]および[IV]中、
w2は、Siのモル比を6とした時のLa元素の仕込み量を表し、
x2は、Siのモル比を6とした時のA元素の仕込み量を表す。) - 前記結晶相が、下記式(1)で表される組成を有することを特徴とする、請求項1または2に記載の蛍光体。
LawAxSi6NyMz (1)
(式(1)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w、x、y、zは、各々独立に、下記式を満たす値である。
wは、1.50≦w≦2.7
xは、0.2≦x≦1.5
yは、8.0≦y≦14.0
zは、0.05≦z≦1.0) - 300nm以上、460nm以下の波長を有する励起光を照射することにより、546nm以上、570nm以下の範囲に発光ピーク波長を有することを特徴とする、請求項1~3のいずれか1項に記載の蛍光体。
- 第1の発光体と、該第1の発光体からの光の照射によって可視光を発する第2の発光体とを備え、
該第2の発光体が、請求項1~4のいずれか1項に記載の窒化物蛍光体の1種以上を、第1の蛍光体として含むことを特徴とする、発光装置。 - 請求項5に記載の発光装置を光源として含むことを特徴とする、照明装置。
- 請求項5に記載の発光装置を光源として含むことを特徴とする、画像表示装置。
- 結晶相が、M元素、La、A元素、Si、Nを含み、かつ
格子定数aが、10.104Å以上、10.154Å以下である蛍光体の製造方法であって、
M源、La源、A源、Si源を原料として、各元素の比率が下記式[III]および[IV]を満たすように原料を調製し、焼成することを特徴とする蛍光体の製造方法。
0.1≦x2/(w2+x2)≦0.5 [III]
2.85≦w2≦3.2 [IV]
(但し、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表す。
また、式[III]および[IV]中、
w2は、Siのモル比を6とした時のLa元素の仕込み量を表し、
x2は、Siのモル比を6とした時のA元素の仕込み量を表す。) - 原料中に含まれる金属元素の組成が下記式(2)で表される組成を満たすように仕込み量を調整することを特徴とする、請求項8に記載の蛍光体の製造方法。
Law2Ax2Si6Ny2Mz2 (2)
(式(2)中、
M元素は、付活元素から選ばれる1種以上の元素を表し、
A元素は、Laおよび付活元素以外の希土類元素から選ばれる1種以上の元素を表し、
w2は前記式[IV]を満たす値であり、
x2、y2、z2は、各々独立に、下記式を満たす値である。
x2は、0.2≦x2≦1.5
y2は、8.0≦y2≦14.0
z2は、0.05≦z2≦1.0)
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009035673A (ja) * | 2007-08-03 | 2009-02-19 | Toshiba Corp | 蛍光体および発光装置 |
WO2010114061A1 (ja) * | 2009-03-31 | 2010-10-07 | 三菱化学株式会社 | 蛍光体、蛍光体の製造方法、蛍光体含有組成物、発光装置、照明装置及び画像表示装置 |
WO2013073598A1 (ja) * | 2011-11-15 | 2013-05-23 | 三菱化学株式会社 | 窒化物蛍光体とその製造方法 |
WO2014123198A1 (ja) * | 2013-02-07 | 2014-08-14 | 三菱化学株式会社 | 窒化物蛍光体とその製造方法 |
JP2016028124A (ja) * | 2014-07-08 | 2016-02-25 | 日亜化学工業株式会社 | 蛍光体およびそれを用いた発光装置ならびに蛍光体の製造方法 |
JP2017041629A (ja) * | 2015-08-20 | 2017-02-23 | 日亜化学工業株式会社 | 発光装置 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4466757B2 (ja) * | 2007-04-18 | 2010-05-26 | 三菱化学株式会社 | 蛍光体、蛍光体含有組成物、発光装置、照明装置、画像表示装置、及び窒素含有化合物 |
CN103045256B (zh) * | 2011-10-17 | 2014-08-27 | 有研稀土新材料股份有限公司 | 一种led红色荧光物质及含有该荧光物质的发光器件 |
JP6167913B2 (ja) * | 2013-04-26 | 2017-07-26 | 日亜化学工業株式会社 | 蛍光体及びそれを用いた発光装置 |
JP6102763B2 (ja) * | 2013-04-26 | 2017-03-29 | 日亜化学工業株式会社 | 蛍光体及びそれを用いた発光装置並びに蛍光体の製造方法 |
WO2015025570A1 (ja) * | 2013-08-20 | 2015-02-26 | 電気化学工業株式会社 | 蛍光体、発光装置及び蛍光体の製造方法 |
JP6406109B2 (ja) * | 2014-07-08 | 2018-10-17 | 日亜化学工業株式会社 | 蛍光体およびそれを用いた発光装置ならびに蛍光体の製造方法 |
-
2017
- 2017-03-28 WO PCT/JP2017/012760 patent/WO2017170609A1/ja active Application Filing
- 2017-03-28 KR KR1020187028020A patent/KR20180123059A/ko unknown
- 2017-03-28 JP JP2018508106A patent/JP7056553B2/ja active Active
- 2017-03-28 EP EP17775146.8A patent/EP3438229B1/en active Active
- 2017-03-28 CN CN201780020580.2A patent/CN108884388A/zh active Pending
-
2018
- 2018-09-27 US US16/144,107 patent/US20190031956A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009035673A (ja) * | 2007-08-03 | 2009-02-19 | Toshiba Corp | 蛍光体および発光装置 |
WO2010114061A1 (ja) * | 2009-03-31 | 2010-10-07 | 三菱化学株式会社 | 蛍光体、蛍光体の製造方法、蛍光体含有組成物、発光装置、照明装置及び画像表示装置 |
WO2013073598A1 (ja) * | 2011-11-15 | 2013-05-23 | 三菱化学株式会社 | 窒化物蛍光体とその製造方法 |
WO2014123198A1 (ja) * | 2013-02-07 | 2014-08-14 | 三菱化学株式会社 | 窒化物蛍光体とその製造方法 |
JP2016028124A (ja) * | 2014-07-08 | 2016-02-25 | 日亜化学工業株式会社 | 蛍光体およびそれを用いた発光装置ならびに蛍光体の製造方法 |
JP2017041629A (ja) * | 2015-08-20 | 2017-02-23 | 日亜化学工業株式会社 | 発光装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3438229A4 * |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2018021193A (ja) * | 2016-07-26 | 2018-02-08 | 三菱ケミカル株式会社 | 焼結蛍光体、発光装置、照明装置、画像表示装置および車両用表示灯 |
WO2018079421A1 (ja) * | 2016-10-28 | 2018-05-03 | 日本特殊陶業株式会社 | 光波長変換部材及び発光装置 |
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US11149193B2 (en) | 2018-04-06 | 2021-10-19 | Nichia Corporation | Method for producing ceramic composite material, ceramic composite material, and light emitting device |
WO2022030586A1 (ja) | 2020-08-06 | 2022-02-10 | 日亜化学工業株式会社 | 窒化物蛍光体及びその製造方法 |
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