JP2019172980A - Manufacturing method of phosphor and phosphor - Google Patents

Abstract

To provide a manufacturing method of a γ-AlON phosphor having high light emission intensity, and the γ-AlON phosphor.SOLUTION: The manufacturing method of a γ-AlON phosphor is provided that includes: a step of preparing a first mixture which includes a compound including Mn, a compound including Li, a compound including Mg, aluminum oxide and aluminum nitride, in which amount of fluorine is 150 mass.ppm or less, performing first heat treatment on the first mixture to obtain a first burned article with average particle diameter D1 measured by an FSSS method of 10.0 μm or more; a step of preparing a second mixture which includes the first burned article, the compound including Mn, the compound including Li, aluminum oxide and aluminum nitride, and in which amount of fluorine is 150 mass.ppm or less, the second mixture contains over 20 mass% and 82 mass% or less of the first burned article, performing a second heat treatment on the second mixture to obtain a second burned article having an average particle diameter D2 measured by the FSSS method of 16.0 μm or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a phosphor manufacturing method and a phosphor, and relates to a method for manufacturing a phosphor having a cubic spinel-type aluminum oxynitride crystal (hereinafter also referred to as “γ-AlON phosphor”) and a γ-AlON phosphor. About.

  Various light emitting devices have been developed that combine a light source such as a light emitting diode (hereinafter also referred to as “LED”) with a phosphor to emit light in white, light bulb color, orange color, etc. according to the principle of light color mixing. Yes. These light emitting devices are used in a wide range of fields, such as light emitting devices for in-vehicle use or indoor lighting, backlight light sources for liquid crystal display devices, displays, and light emitting devices for illumination.

  Known phosphors used in such light emitting devices include inorganic phosphors having a crystal structure containing nitrogen, such as sialon phosphors, oxynitride phosphors, and nitride phosphors. A γ-AlON phosphor obtained by activating Mn to a spinel-type aluminum oxynitride crystal (γ-AlON) belonging to a cubic system is also known (Patent Document 1). The γ-AlON phosphor is excited by blue light having an emission peak wavelength within a range of 410 nm or more and 470 nm or less, for example, and emits green light.

Japanese Patent Laid-Open No. 2006-216711

However, when the γ-AlON phosphor is combined with a light emitting element having an emission peak wavelength within a range of 380 nm to 485 nm (hereinafter also referred to as “near ultraviolet to blue region”), the emission intensity is further improved. Is desired.
Accordingly, an object of the present invention is to provide a γ-AlON phosphor having high emission intensity by light excitation in the near ultraviolet to blue region and a method for producing the same.

  Means for solving the above problems are as follows, and the present invention includes the following aspects.

  The first aspect of the present invention includes a compound containing Mn, a compound containing Li, a compound containing Mg, aluminum oxide, and aluminum nitride, and the amount of fluorine is relative to the total amount of the first mixture excluding fluorine. A first mixture having 150 ppm by mass or less is prepared, a first heat treatment is performed on the first mixture, and a first calcined product having an average particle diameter D1 of 10.0 μm or more measured by the Fisher sub-sieve sizers method is obtained. The amount of fluorine with respect to the total amount of the second mixture including the step of obtaining, the first fired product, the compound containing Mn, the compound containing Li, the compound containing Mg, aluminum oxide, and aluminum nitride, excluding fluorine Is prepared, the second mixture is 20% by mass of the first fired product based on the total amount of the second mixture excluding fluorine. Including a step of obtaining a second calcined product having an average particle diameter D2 of 16.0 μm or more, which is greater than 82% by mass and subjected to the second heat treatment on the second mixture and measured by the Fisher Sub-Seedsizer method. , A method for producing a γ-AlON phosphor.

The second aspect of the present invention is a γ-AlON phosphor having a composition represented by the following formula (I) and having an average particle diameter D2 of 16.0 μm or more measured by the Fisher Sub-Seedsizer method. .
_{Mn a Mg b Li c Al d} O e N f F g (I)
(In the formula (I), a, b, c, d, e, f and g are 0.005 ≦ a ≦ 0.02, 0.01 ≦ b ≦ 0.035, 0 when a + b + c + d + e + f = 1. .01 ≦ c ≦ 0.04, 0.3 ≦ d ≦ 0.45, 0.4 ≦ e ≦ 0.6, 0.03 ≦ f ≦ 0.06, 0 ≦ g ≦ 0.00016 is there.)

  According to the present invention, it is possible to provide a method for producing a γ-AlON phosphor and a γ-AlON phosphor having high emission intensity by light excitation in the near ultraviolet to blue region.

FIG. 1 is a flowchart showing a process sequence of a method for manufacturing a γ-AlON phosphor according to the first embodiment of the present invention.

  Hereinafter, embodiments of the method for manufacturing a γ-AlON phosphor and the γ-AlON phosphor according to the present invention will be described. However, the following embodiments are exemplifications for embodying the technical idea of the present invention, and the present invention is not limited to the following γ-AlON phosphor manufacturing method and γ-AlON phosphor. The relationship between the color name and the chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, and the like comply with JIS Z8110.

Method for Producing γ-AlON Phosphor A method for producing a γ-AlON phosphor according to the first embodiment of the present invention includes a compound containing Mn, a compound containing Li, a compound containing Mg, aluminum oxide, and aluminum nitride. A first mixture having an amount of fluorine of 150 ppm by mass or less is prepared with respect to the total amount of the first mixture including and excluding fluorine, the first mixture is subjected to a first heat treatment, and Fischer Sub-Seedsizers ( A step of obtaining a first fired product having an average particle diameter D1 of 10.0 μm or more measured by a Fisher Sub-Sieve Sizer method (hereinafter also referred to as “FSSS method”), and the first fired product and Mn. The total amount of the compound, the compound containing Li, the compound containing Mg, aluminum oxide, and aluminum nitride, excluding fluorine, Preparing a second mixture having an elemental amount of 150 ppm by mass or less, wherein the second mixture is more than 20% by mass and less than 82% by mass of the first fired product with respect to the total amount of the second mixture; And a second heat treatment is performed on the second mixture to obtain a second fired product having an average particle diameter D2 measured by the FSSS method of 16.0 μm or more.

  The average particle diameter measured by the FSSS method is a numerical value called a Fisher Sub-Sieve Sizer's Number. The FSSS method is a kind of air permeation method, and is a method of measuring the specific surface area of particles using air flow resistance to determine the particle size of the particles.

  FIG. 1 is a flowchart showing an example of a process sequence of a method for manufacturing a γ-AlON phosphor. The manufacturing method of the γ-AlON phosphor includes a step S102 in which a first heat treatment is performed on the first mixture to obtain a first fired product having an average particle diameter D1 measured by the FSSS method of 10.0 μm or more. Step S104 is performed in which a second heat treatment is performed to obtain a second fired product having an average particle diameter D2 measured by the FSSS method of 16.0 μm or more. In the manufacturing method of the γ-AlON phosphor, the second mixture is prepared before the step S101 of preparing the first mixture and the step S104 of obtaining the second fired product before the step S102 of obtaining the first fired product. Step S103 is included. Moreover, it is preferable that the manufacturing method of (gamma) -AlON fluorescent substance includes process S105 which performs an annealing process and obtains an annealing treatment thing after the process of obtaining a 2nd baking products. Further, although the illustration of the manufacturing method of the γ-AlON phosphor is omitted, it may include a dispersion and classification step after the first heat treatment and before the second heat treatment, and after the second heat treatment. Thus, a dispersion and classification step may be included before the annealing treatment, and a dispersion and classification step may be included after the annealing treatment.

  A method for producing a γ-AlON phosphor includes preparing a second mixture containing a compound containing Mn, a compound containing Li, a compound containing Mg, aluminum oxide and aluminum nitride together with the first fired product. By performing the second heat treatment, the first fired product becomes a seed crystal to promote crystal growth, and a second fired product having a relatively large average particle diameter D2 of 16.0 μm measured by the FSSS method is obtained. Can do. The obtained second fired product has an average particle size that is easy to handle when forming the light emitting device. The second fired product obtained by the method for producing a γ-AlON phosphor may have an average particle diameter D2 measured by the FSSS method of 17.0 μm or more, 18.0 μm or more, or 19.0 μm. It may be the above. Moreover, it is preferable that the average particle diameter D2 measured by the FSSS method is 60.0 micrometers or less as for the 2nd baked product obtained by the said manufacturing method. The obtained second fired product contains a large amount of γ-AlON crystals having a stable crystal structure, and the crystal structure is stabilized, so that a γ-AlON phosphor having high emission intensity can be obtained. When the average particle diameter measured by the FSSS method of the obtained γ-AlON phosphor is larger than 60.0 μm, the fluorescence that is a member constituting the light emitting device when the γ-AlON phosphor is used in the light emitting device. The dispersibility in the resin contained in the member is poor, and it is difficult to inject the resin composition containing the γ-AlON phosphor into the molded body constituting the light emitting device, and the workability when manufacturing the light emitting device is reduced. There is a fear. When the average particle diameter measured by the FSSS method of the γ-AlON phosphor is larger than 60.0 μm, when used in combination with a phosphor emitting other colors than the γ-AlON phosphor, The balance of emitted light may be lost, making it difficult to mix colors so that a desired color is obtained, and color unevenness may occur.

  According to the manufacturing method, since the amount of fluorine is small in both the first mixture for obtaining the first fired product and the second mixture for obtaining the second fired product, they are included in the first fired product and the second fired product. The amount of fluorine is small, and it is possible to suppress the body color of the phosphor from becoming dull when fluorine enters the crystal structure, and a γ-AlON phosphor having high emission intensity can be obtained. Further, fluorine enters the crystal structure of the first fired product or the second fired product, and formation of unstable phases such as amorphous parts, low crystal parts with high dislocation density and defect density, and the like can be suppressed.

Preparation of first mixture The first mixture is obtained by mixing a compound containing Mn, a compound containing Li, a compound containing Mg, aluminum oxide, and aluminum nitride. In the first mixture, the amount of fluorine is 150 mass ppm or less with respect to the total amount of the first mixture excluding fluorine. When the amount of fluorine in the first mixture exceeds 150 mass ppm with respect to the total amount of the first mixture excluding fluorine, the amount of fluorine in the first fired product that becomes a seed crystal in the second heat treatment is large. When the fluorine enters the first fired product, the body color of the phosphor becomes dull and it becomes difficult to obtain a γ-AlON phosphor having high emission intensity. In addition, if fluorine enters the obtained first fired product, the crystal structure becomes unstable, and the emission intensity of the γ-AlON phosphor composed of the second fired product obtained by crystal growth using the first fired product as a seed crystal. May decrease. In order for the amount of fluorine in the first mixture to be 150 mass ppm or less with respect to the total amount of the first mixture excluding fluorine, any compound of a compound containing Mn, a compound containing Li, and a compound containing Mg It is preferable to remove fluoride. Even when fluoride is removed as the compound used in the first mixture, the amount of fluorine in the first mixture is usually 1 ppm or more and 5 ppm or more with respect to the total amount of the first mixture excluding fluorine. In some cases, it may be 10 ppm or more.

  In the method for producing a γ-AlON phosphor, in order to promote a reaction between raw materials in a mixture, to promote a solid phase reaction more uniformly, and to promote crystal growth to obtain a fired product having a relatively large particle size. In addition, the flux may be included in the mixture together with the raw material. As the flux, a fluoride containing an element constituting the crystal structure of the phosphor may be used. In the method for producing a γ-AlON phosphor, in order for the amount of fluorine to be 150 mass ppm or less with respect to the total amount of the first mixture or the second mixture excluding fluorine, the compound used as a raw material or a flux is It is preferable to remove the compound.

Examples of the compound containing Mn include carbonates, oxides, hydroxides, nitrates and sulfates containing Mn. The compound containing Mn may be in the form of a hydrate. _{Specifically, MnCO 3, MnO 2, Mn} 2 O 3, Mn 3 O 4, MnO, Mn (OH) 2, Mn (NO 3) 2, MnSO 4 , and the like. The compound containing Mn may be used individually by 1 type, and may be used in combination of 2 or more type. Among the compounds containing Mn, carbonates and oxides are preferable because they are easy to handle. Carbonate containing Mn (MnCO ₃₎ has good stability in air, is easily decomposed by heating, does not easily retain elements other than the target composition, and easily suppresses the decrease in emission intensity due to residual impurity elements. ) Is more preferable. Compounds containing Mn are fluorides, for example, it is preferable to remove the MnF _2.

Examples of the compound containing Mg include Mg-containing oxides, hydroxides, carbonates, nitrates, sulfates, and nitrides. The compound containing Mg may be in the form of a hydrate. Specific examples include MgO, MgCO ₃ , Mg (NO ₃ ) ₂ , MgSO ₄ , and Mg ₃ N ₂ . The compound containing Mg may be used individually by 1 type, and may be used in combination of 2 or more type. Among the compounds containing Mg, carbonates and oxides are preferable because they are easy to handle. Oxide (MgO) containing Mg, because it is stable in air, easily decomposes by heating, elements other than the target composition hardly remain, and it is easy to suppress a decrease in light emission intensity due to residual impurity elements. Is more preferable. The compound containing Mg preferably excludes fluorides such as MgF ₂ .

Examples of the compound containing Li include carbonates, oxides, aluminates, hydroxides, nitrates, sulfates, and nitrides containing Li. The compound containing Li may be in the form of a hydrate. _{Specifically, Li 2 CO 3, Li 2} O, LiAlO 2, LiOH, LiNO 3, Li 2 SO 4, Li 3 N and the like. The compound containing Li may be used individually by 1 type, and may be used in combination of 2 or more type. Among the compounds containing Li, carbonates and oxides are preferable because they are easy to handle. Carbonate containing Li (Li ₂₎ has good stability in air, is easily decomposed by heating, does not easily retain elements other than the target composition, and easily suppresses a decrease in emission intensity due to residual impurity elements. CO ₃ ) is more preferred. The compound containing Li preferably excludes fluorides such as LiF.

  The first mixture includes aluminum oxide and aluminum nitride. Aluminum oxide and aluminum nitride form a skeleton of the crystal structure of aluminum oxynitride (AlON). The first mixture is composed of a compound containing Mn, a compound containing Mg, a compound containing Li, aluminum oxide and aluminum nitride so as to have a desired mixing ratio, and then, for example, a ball mill, a vibration mill, a hammer mill, a mortar, You may grind and mix using a pestle. When the first mixture is pulverized and mixed using a mortar and pestle, aluminum oxide (alumina), which is the same material as the raw material contained in the first mixture, is used to suppress mixing of elements other than the target composition. It is preferable to use a mortar. The first mixture may be mixed using a mixer such as a ribbon blender, a Henschel mixer, or a V-type blender, or may be pulverized and mixed using both a dry pulverizer and a mixer. The mixing may be dry mixing, or may be wet mixed by adding a solvent or the like. The mixing is preferably dry mixing. This is because the dry process can shorten the process time and improve the productivity than the wet process.

1st heat processing 1st heat processing performs 1st heat processing to a 1st mixture, and obtains the 1st baking products whose average particle diameter D1 measured by FSSS method is 10.0 micrometers or more.

  In the first heat treatment, the first mixture is heat treated by putting it in a crucible or boat made of a carbon material such as graphite, boron nitride (BN), aluminum oxide (alumina), tungsten (W), or molybdenum (Mo). can do.

  The temperature of the first heat treatment is preferably 1600 ° C. or higher and 1900 ° C. or lower, more preferably 1650 ° C. or higher and 1900 ° C. or lower, and further preferably 1700 ° C. or higher and 1850 ° C. or lower. When the first heat treatment temperature is 1600 ° C. or more and 1900 ° C. or less, the average particle diameter D1 measured by the FSSS method is 10.0 μm or more, and a first fired product containing γ-AlON crystals can be obtained. For example, an electric furnace or a gas pressurizing furnace can be used for the heat treatment of the first mixture.

  The first heat treatment atmosphere is preferably obtained by firing the first mixture in a nitrogen atmosphere at a pressure of 0.2 MPa to 1.2 MPa to obtain a first fired product.

  The first heat treatment time varies depending on the rate of temperature rise, the heat treatment atmosphere, etc., and preferably reaches 1st heat treatment temperature in the range of 1600 ° C. or more and 1900 ° C. or less, preferably 1 hour or more, more preferably 2 hours or more, More preferably, it is 3 hours or more, preferably within 20 hours, more preferably within 18 hours, still more preferably within 15 hours.

  The first fired product obtained by the first heat treatment contains γ-AlON crystals, may contain AlON solid solution crystals, and may be a composite of AlON and aluminum nitride (AlN).

  The first fired product has an average particle diameter D1 measured by the FSSS method of 10.0 μm or more, preferably 11.0 μm or more, more preferably 12.0 μm or more. The first fired product preferably has a larger average particle size D1 measured by the FSSS method, but the average particle size D1 of the first fired product obtained from the first mixture not containing the flux is usually less than 16.0 μm. is there. If the average particle diameter D1 measured by the FSSS method is 10.0 μm or more, the first fired product becomes a seed crystal in the second heat treatment, and crystal growth is promoted, and the first fired product is measured by the FSSS method. A second fired product having an average particle diameter D2 of 16.0 μm or more can be obtained.

Preparation of second mixture The second mixture is obtained by mixing the first fired product, the compound containing Mn, the compound containing Li, the compound containing Mg, aluminum oxide, and aluminum nitride. The amount of fluorine in the second mixture is 150 mass ppm or less with respect to the total amount of the second mixture excluding fluorine. When the amount of fluorine in the second mixture exceeds 150 mass ppm with respect to the total amount of the second mixture excluding fluorine, the amount of fluorine in the second fired product is large, and a large amount in the second fired product. When fluorine enters, the body color of the second fired product that becomes the γ-AlON phosphor becomes dull, and it becomes difficult to obtain a γ-AlON phosphor having high emission intensity. In addition, when a large amount of fluorine enters the second fired product, it is presumed that the crystal structure becomes unstable due to the fluorine entering the crystal structure. In order for the amount of fluorine in the second mixture to be 150 ppm by mass or less with respect to the total amount of the second mixture excluding fluorine, any of the compound containing Mn, the compound containing Li, and the compound containing Mg A compound other than a compound containing fluorine is preferable. Specifically, for example, it is preferable to exclude MnF ₂ , LiF, and MgF ₂ . Even when fluoride is removed as a compound used in the second mixture, the amount of fluorine in the second mixture is usually 1 ppm or more and 5 ppm or more with respect to the total amount of the second mixture excluding fluorine. In some cases, it may be 10 ppm or more, and in some cases it is 20 ppm or more.

  The content of the first fired product in the second mixture is in the range of more than 20% by mass and 82% by mass or less with respect to the total amount of the second mixture excluding fluorine. The content of the first fired product in the second mixture is preferably in the range of 25% by mass or more and 82% by mass or less, more preferably 30% by mass or more, with respect to the total amount of the second mixture excluding fluorine. Within the range of 81% by mass or less, more preferably within the range of 35% by mass or more and 81% by mass or less, still more preferably within the range of 40% by mass or more and 80% by mass or less, and particularly preferably 40% by mass. % Or more and 75% by mass or less. In the second heat treatment, if the content of the first fired product in the second mixture is in the range of more than 20% by mass and 82% by mass or less with respect to the total amount of the second mixture excluding fluorine, The first fired product becomes a seed crystal to promote crystal growth, and a relatively large second fired product having an average particle diameter D2 measured by the FSSS method of 16.0 μm or more is obtained. -It can be used as an AlON phosphor. If the content of the first fired product in the second mixture is 20% by mass or less, the amount of the first fired product that becomes the seed crystal is too small, and the crystal growth is not promoted in the second heat treatment, and the average grain size It becomes difficult to obtain a second fired product having a relatively large diameter. The γ-AlON crystal or the AlON solid solution crystal is a relatively hard crystal, but the second fired product contains more than 20% by mass of the first fired product that becomes the seed crystal. Crystal growth can be promoted to obtain a second fired product having a relatively large particle size. When the content of the first baked product in the second mixture exceeds 82% by mass with respect to the total amount of the second mixture excluding the elemental fluorine, the amount of the compound that is relatively a raw material contained in the second mixture The crystal growth is not promoted, and the second fired product having a large particle size cannot be obtained.

As the compound containing Mn, the compound exemplified as the compound contained in the first mixture can be used as the compound containing Li, and as the compound containing Mg, any compound can be used. The compound containing Mn, the compound containing Li, or the compound containing Mg may be the same type of compound as the compound contained in the first mixture, or may be a different type of compound. As for the compound containing Mn, the compound containing Li, or the compound containing Mg, any compound may be used singly or in combination of two or more. A compound containing Mn, a compound containing Li, or a compound containing Mg is preferably a carbonate or oxide from the viewpoint of easy handling, and a carbonate containing Mn from the viewpoint of stability of the compound, decomposability, and residual impurity elements hardly remaining. (MnCO ₃ ), carbonate containing Li (Li ₂ CO ₃ ), or oxide containing Mg (MgO) is more preferable.

  It is preferable that a 2nd mixture contains 15 mass% or more of aluminum oxide and aluminum nitride with respect to the whole quantity of the 2nd mixture except a fluorine. Aluminum oxide and aluminum nitride form a skeleton of an AlON crystal structure. When the total content of aluminum oxide and aluminum nitride in the second mixture is 15% by mass or more, crystal growth is promoted using the first fired product as a seed crystal, and the average particle diameter D2 measured by the FSSS method is 16. A second fired product having a large particle size of 0 μm or more can be obtained. The total content of aluminum oxide and aluminum nitride in the second mixture is more preferably 16% by mass or more, further preferably 20% by mass or more, based on the total amount of the second mixture excluding fluorine.

Second heat treatment In the second heat treatment, the second mixture is subjected to a second heat treatment to obtain a second fired product having an average particle diameter D2 of 16.0 μm or more measured by the FSSS method. The second mixture can be subjected to the second heat treatment by being put in a crucible, a boat or the like of the material exemplified when the first heat treatment is performed on the first mixture.

  The temperature of the second heat treatment is preferably in the range of 1600 ° C. to 1900 ° C., more preferably in the range of 1650 ° C. to 1900 ° C., and further preferably in the range of 1700 ° C. to 1850 ° C. is there. When the second heat treatment temperature is in the range of 1600 ° C. or more and 1900 ° C. or less, the first fired product is used as a seed crystal to further promote crystal growth, and the average particle diameter D2 measured by the FSSS method is 16.0 μm or more. A certain second fired product containing γ-AlON crystals can be obtained. For the heat treatment of the second mixture, for example, an electric furnace, a gas pressurizing furnace, or the like can be used in the same manner as the apparatus used for the heat treatment of the first mixture.

  As the second heat treatment atmosphere, the atmosphere exemplified as the first heat treatment atmosphere can be applied. The second heat treatment atmosphere may be the same atmosphere as the first heat treatment atmosphere. The second heat treatment atmosphere is preferably obtained by firing the second mixture in a nitrogen atmosphere to obtain a second fired product. The nitrogen atmosphere may contain other gases such as hydrogen, oxygen, and ammonia in addition to the nitrogen gas. The nitrogen gas content in the nitrogen atmosphere is, for example, 90% by volume or more, preferably 95% by volume or more, more preferably 99% by volume or more, and may be 100% by volume.

  The second heat treatment time varies depending on the rate of temperature rise, the heat treatment atmosphere, and the like, and after reaching the second heat treatment temperature in the range of 1600 ° C. or more and 1900 ° C. or less, preferably 1 hour or more, more preferably 2 hours or more, More preferably, it is 3 hours or more, preferably within 20 hours, more preferably within 18 hours, still more preferably within 15 hours.

  The second fired product obtained by the second heat treatment contains γ-AlON crystals, may contain AlON solid solution crystals, and may be a composite of AlON-AlN.

  The second fired product has an average particle diameter D2 measured by the FSSS method of 16.0 μm or more, preferably 60.0 μm or less, more preferably 50.0 μm or less, further preferably 40.0 μm or less, and still more preferably. It is 30.0 μm or less, particularly preferably 25.0 μm or less. The second fired product preferably has an average particle diameter D2 measured by the FSSS method of 17.0 μm or more, more preferably 18.0 μm or more. If the average particle diameter D2 of the second fired product is 16.0 μm or more, the second fired product becomes large enough to absorb light from the light source and emit light in a desired wavelength range. It can be used as a γ-AlON phosphor having If the average particle diameter D2 of the second fired product is preferably 60.0 μm or less, more preferably 50.0 μm or less, dispersibility in the resin constituting the fluorescent member of the light-emitting device when forming the light-emitting device. Is good. Further, the second fired product can be used as a γ-AlON phosphor that can be easily injected into a molded body constituting the light emitting device and can be easily handled when the light emitting device is formed. In addition, if the average particle diameter D2 of the second fired product is preferably 60.0 μm or less, more preferably 50.0 μm or less, the second fired product is used as a γ-AlON phosphor in combination with other phosphors to produce a light emitting device. When used in the above, it is possible to mix the light emitted from each phosphor in a well-balanced manner without losing the balance of the color mixture due to the light emitted from the phosphor having a too large particle diameter, and to reduce the color unevenness. Mixed color light can be obtained.

Annealing The γ-AlON phosphor manufacturing method preferably includes a step of annealing the second fired product after the second heat treatment to obtain an annealed product. The second fired product can increase the proportion of divalent Mn in the γ-AlON phosphor by reducing non-divalent Mn present in the second fired product by annealing. -The emission intensity of the AlON phosphor can be increased.

  The annealing treatment temperature is preferably lower than the first heat treatment temperature or the second heat treatment temperature. The annealing temperature is preferably in the range of 1100 ° C. or higher and 1500 ° C. or lower, more preferably in the range of 1100 ° C. or higher and 1400 ° C. or lower, and still more preferably in the range of 1150 ° C. or higher and 1350 ° C. or lower. If the temperature of the annealing treatment is in the range of 1100 ° C. or more and 1500 ° C. or less, the annealing treatment reduces Mn other than divalent contained in the second fired product, and occupies the divalent Mn in the γ-AlON phosphor. The ratio can be increased, and a γ-AlON phosphor with high emission intensity can be obtained.

  In the annealing process, it is preferable to raise the atmosphere in which the second fired product is placed to the temperature of the annealing process, and then hold this temperature for a certain period of time. The annealing time is preferably 1 hour to 48 hours, more preferably 2 hours to 24 hours, and further preferably 3 hours to 20 hours. When the annealing treatment time is within a predetermined range, Mn other than divalent contained in the annealed product can be reduced, and the proportion of divalent Mn in the γ-AlON phosphor can be increased. -The emission intensity of the AlON phosphor can be increased.

  The atmosphere in the annealing treatment is preferably a reducing atmosphere. The atmosphere in the annealing process may be an atmosphere containing at least one rare gas selected from the group consisting of helium, neon, and argon and hydrogen, and more preferably contains at least argon and hydrogen in the atmosphere.

  When the annealing treatment is performed, the pressure is preferably atmospheric pressure (about 0.1 MPa) or more and 1 MPa or less, more preferably atmospheric pressure or more and 0.5 MPa or less, and further preferably atmospheric pressure or more and 0.2 MPa or less.

  The annealing process may be performed under a reduced pressure lower than the atmospheric pressure. Here, “under reduced pressure” does not exclude the presence of a gas during annealing, and a gas such as rare gas, nitrogen, hydrogen, or oxygen may also exist during the annealing under reduced pressure.

  The annealed product has an average particle diameter D3 measured by the FSSS method of preferably 16.0 μm or more, preferably 60.0 μm or less, more preferably 50.0 μm or less, still more preferably 40.0 μm or less, and even more preferably Is 30.0 μm or less, particularly preferably 25.0 μm or less. The annealed product has an average particle diameter D3 measured by the FSSS method of preferably 17.0 μm or more, and more preferably 18.0 μm or more. In the annealed product, the average particle size D3 of the annealed product may be the same as or different from the average particle size D2 of the second fired product. If the average particle diameter D3 measured by the FSSS method of the annealed product is 16.0 μm or more, it will be large enough to absorb light from the light source and emit light in the desired wavelength range. It can be used as a γ-AlON phosphor having high emission intensity. If the average particle diameter D3 of the annealed product is preferably 60.0 μm or less, more preferably 50.0 μm or less, the dispersibility in the resin constituting the fluorescent member of the light-emitting device can be improved when forming the light-emitting device. Good. Further, an annealed product can be used as a γ-AlON phosphor that can be easily injected into a molded body constituting the light emitting device and can be easily handled when the light emitting device is formed. If the average particle diameter D3 of the annealed product is preferably 60.0 μm or less, more preferably 50.0 μm or less, the annealed product is used as a γ-AlON phosphor in combination with other phosphors for use in a light emitting device. In this case, the light emitted from the phosphors having a too large particle size can be mixed in a balanced manner with the light emitted from each phosphor without losing the balance of the color mixture, and the desired color mixture light with suppressed color unevenness. Can be obtained.

Dispersion treatment and classification treatment Dispersion treatment and classification treatment may be performed on the first fired product, the second fired product, or the annealed product. The dispersion treatment or the classification treatment may be performed on any of the first fired product, the second fired product, and the annealed product, or may be performed on all of the first fired product, the second fired product, and the annealed product. As the dispersion process, for example, a wet dispersion line may be performed. As the classification treatment, for example, after wet sieving, dehydration, drying, dry sieving, or the like may be performed. As a solvent used for wet dispersion, for example, deionized water can be used. Solid dispersion media such as alumina balls and zirconia balls may be used for wet dispersion. By performing wet dispersion, it is possible to obtain a γ-AlON phosphor having a good dispersibility in the resin constituting the fluorescent member of the light emitting device and a size easy to handle. After the wet dispersion, as the classification treatment, the fired product and the solvent are placed on the sieve, and a flow of solvent is passed through the sieve while applying various vibrations to mesh the first fired product, the second fired product, or the annealed product. You may let it pass and perform wet sieving. After wet sieving, dehydration and drying may be performed, and further dry sieving may be performed. Through a dry sieve, large particles that do not pass through the sieve can be removed. In the classification treatment, the sieve opening used when performing wet sieving or dry sieving is not particularly limited, and a sieve having an opening corresponding to the target particle size can be used.

The second fired product obtained by the method for producing the γ-AlON phosphor preferably includes a composition represented by the following formula (I). Moreover, it is preferable that the annealed product obtained by annealing the second fired product includes a composition represented by the following formula (I).
_{Mn a Mg b Li c Al d} O e N f F g (I)
(In the formula (I), a, b, c, d, e, f and g are 0.005 ≦ a ≦ 0.02, 0.01 ≦ b ≦ 0.035, 0 when a + b + c + d + e + f = 1. .01 ≦ c ≦ 0.04, 0.3 ≦ d ≦ 0.45, 0.4 ≦ e ≦ 0.6, 0.03 ≦ f ≦ 0.06, 0 ≦ g ≦ 0.00016 is there.)

γ-AlON phosphor The γ-AlON phosphor according to the second embodiment of the present invention includes a composition represented by the formula (I), and has an average particle diameter measured by the FSSS method of 16.0 μm or more. is there. The γ-AlON phosphor is preferably a second fired product or an annealed product obtained by the manufacturing method according to the first embodiment of the present invention.

  The γ-AlON phosphor containing the composition represented by the formula (I) has an average particle size measured by the FSSS method of 16.0 μm or more, preferably 60.0 μm or less, more preferably 50.0 μm or less. More preferably, it is 40.0 μm or less, more preferably 30.0 μm or less, and particularly preferably 25.0 μm or less. The γ-AlON phosphor has an average particle size measured by the FSSS method of preferably 17.0 μm or more, more preferably 18.0 μm or more. The average particle size measured by the FSSS method of the γ-AlON phosphor is the first when the γ-AlON phosphor is the second fired product produced by the production method according to the first embodiment of the present invention. It is synonymous with the average particle diameter D2 of two baked products. When the γ-AlON phosphor is an annealed product manufactured by the above manufacturing method, the average particle diameter measured by the FSSS method of the γ-AlON phosphor is synonymous with the average particle diameter D3 of the annealed product. is there. If the average particle size measured by the FSSS method of the γ-AlON phosphor is 16.0 μm or more, it will be large enough to absorb light from the light source and emit light in the desired wavelength range, and high emission intensity Have If the average particle size of the γ-AlON phosphor measured by the FSSS method is preferably 60.0 μm or less, more preferably 50.0 μm or less, the resin constituting the fluorescent member of the light emitting device when the light emitting device is formed Good dispersibility inside. Moreover, it is easy to inject | pour into the molded object which comprises a light-emitting device, and it is easy to handle at the time of formation of a light-emitting device. In addition, if the average particle size of the γ-AlON phosphor measured by the FSSS method is preferably 60.0 μm or less, more preferably 50.0 μm or less, the γ-AlON phosphor is replaced with a material other than the γ-AlON phosphor. When used in a light-emitting device in combination with a phosphor, light emitted from each phosphor can be mixed in a well-balanced manner without losing the balance of color mixing due to light emitted from the phosphor having a particle size that is too large. Desired color mixture light with suppressed color unevenness can be obtained.

  In the γ-AlON phosphor including the composition represented by the formula (I), Mn is an activation element that becomes a light emission center. In the composition represented by the formula (I), the variable a is a molar ratio of Mn as an activating element, and the total molar ratio of elements excluding fluorine constituting the composition represented by the formula (I). As long as 1 (a + b + c + d + e + f = 1), a number satisfying 0.005 or more and 0.02 or less (0.005 ≦ a ≦ 0.02) is obtained by γ-AlON phosphor by photoexcitation in the near ultraviolet to blue region The emission intensity can be increased. In the present specification, the “molar ratio” refers to the molar amount of an element in 1 mol of the phosphor having the chemical composition represented by the formula (I). In the composition represented by the formula (I), if the variable a is less than 0.005, the amount of the activation element is too small to increase the emission intensity of the γ-AlON phosphor. In the composition represented by the formula (I), when the variable a exceeds 0.02, the amount of the activating element is too large, and the emission intensity may decrease due to concentration quenching. The variable a preferably satisfies 0.007 or more and 0.018 or less (0.007 ≦ a ≦ 0.018), more preferably 0.008 or more and 0.015 or less (0.008 ≦ a ≦ 0.015). Is a number.

  In the γ-AlON phosphor containing the composition represented by the formula (I), Mg is a divalent metal, so it is an element that easily dissolves in the AlON crystal and stabilizes the crystal structure. In the composition represented by the formula (I), the variable b is the molar ratio of Mg, and the total molar ratio of elements excluding fluorine constituting the composition represented by the formula (I) is 1 (a + b + c + d + e + f = 1), if it is a number satisfying 0.01 or more and 0.035 or less (0.01 ≦ b ≦ 0.035), the AlON crystal can be stabilized and Mn as an activation element is taken in. Can be made easier. In the composition represented by the formula (I), if the variable b is less than 0.01, the crystal structure is difficult to stabilize. In the composition represented by the formula (I), when the variable b exceeds 0.035, the amount of elements incorporated into the AlON crystal is excessively increased and the crystal structure becomes unstable, resulting in an unstable phase, for example, amorphous. The ratio of the mass part and the low crystal part increases, and the luminescence intensity of the γ-AlON phosphor may decrease. The variable b preferably satisfies 0.012 to 0.035 (0.012 ≦ b ≦ 0.035), more preferably 0.015 to 0.030 (0.015 ≦ b ≦ 0.030). Is a number.

  In the γ-AlON phosphor including the composition represented by the formula (I), Li is a monovalent metal, so that Li is an element that easily dissolves in the AlON crystal and stabilizes the crystal structure. In the composition represented by the formula (I), the variable c is the molar ratio of Li, and the total molar ratio of elements excluding fluorine constituting the composition represented by the formula (I) is 1 (a + b + c + d + e + f = 1), if it is a number satisfying 0.01 or more and 0.04 or less (0.01 ≦ c ≦ 0.04), the AlON crystal can be stabilized and Mn as an activation element is taken in. Can be made easier. In the composition represented by the formula (I), if the variable c is less than 0.01, it is difficult to stabilize the crystal structure. In the composition represented by the formula (I), when the variable c exceeds 0.04, the amount of elements taken into the AlON crystal becomes too large and the crystal structure becomes unstable, and an unstable phase, for example, amorphous The ratio of the mass part and the low crystal part increases, and the luminescence intensity of the γ-AlON phosphor may decrease. The variable c preferably satisfies 0.012 to 0.035 (0.012 ≦ c ≦ 0.035), more preferably 0.015 to 0.030 (0.015 ≦ c ≦ 0.030). Is a number.

  In the γ-AlON phosphor including the composition represented by the formula (I), Al, O, and N are elements that form the skeleton of the γ-AlON crystal. In the composition represented by the formula (I), the variables d, e, and f are the molar ratios of Al, O, and N, respectively, and the elements of the elements excluding fluorine constituting the composition represented by the formula (I). When the total molar ratio is 1 (a + b + c + d + e + f = 1), the variable d is 0.3 or more and 0.45 or less (0.3 ≦ d ≦ 0.45), and the variable e is 0.4 or more and 0.6 or less. (0.4 ≦ e ≦ 0.6), if the variable f is a number satisfying 0.03 or more and 0.06 or less (0.03 ≦ f ≦ 0.06), stable γ-AlON crystals are included. . The variable d is preferably a number satisfying 0.35 or more and 0.40 or less (0.35 ≦ d ≦ 0.40). The variable e is preferably a number satisfying 0.45 or more and 0.55 or less (0.45 ≦ e ≦ 0.55). The variable f is preferably a number satisfying 0.035 or more and 0.055 or less (0.035 ≦ f ≦ 0.055).

  In the γ-AlON phosphor including the composition represented by the formula (I), F is an element that can be included as an unavoidable impurity in the raw material or flux or in the manufacturing process. In the manufacture of the phosphor, a fluoride containing an element that can form a γ-AlON crystal may be used as a flux in order to promote a solid phase reaction between raw materials. However, it has been found that when fluoride is used as the flux, fluorine enters the γ-AlON crystal, the body color of the γ-AlON phosphor becomes dull, and the emission intensity decreases. In addition, when fluorine enters the γ-AlON crystal, the crystal structure of the γ-AlON crystal becomes unstable, and in the emission spectrum of the γ-AlON phosphor, the full width at half maximum (FWHM, below) It was found that there is a tendency for the “half-width”) to become wider. The full width at half maximum of the phosphor refers to the wavelength width of an emission peak showing an emission intensity of 50% of the maximum emission intensity in the emission spectrum.

  Since the γ-AlON phosphor according to the second embodiment of the present invention has a small F molar ratio in the composition represented by the formula (I), it suppresses the dullness of the body color of the γ-AlON phosphor. , Has high emission intensity. In addition, since the γ-AlON phosphor has a small F molar ratio in the composition represented by the formula (I), the γ-AlON crystal is stable, and the half-value width of the emission peak in the emission spectrum is kept narrow. The color purity is high. Therefore, when a light emitting device using a γ-AlON phosphor is used as a backlight light source of a liquid crystal display device, the liquid crystal display device can reproduce a wide range of colors on chromaticity coordinates. The γ-AlON phosphor containing the composition represented by the formula (I) preferably has a smaller amount of F. In the composition represented by the formula (I), the variable g represents a molar ratio of F, and the variable g is a number satisfying 0 or more and 0.00016 or less (0 ≦ g ≦ 0.00016), preferably The number satisfies 0 or more and 0.00015 or less (0 ≦ g ≦ 0.00015), more preferably 0 or more and 0.00010 or less (0 ≦ g ≦ 0.00010).

  The amount of fluorine (F) in the γ-AlON phosphor containing the composition represented by the formula (I) is preferably less than 160 ppm by mass with respect to the total amount of the γ-AlON phosphor excluding fluorine. Preferably it is 150 mass ppm or less, More preferably, it is 120 mass ppm or less. If the amount of fluorine in the γ-AlON phosphor containing the composition represented by the formula (I) is less than 160 ppm by mass, dullness of the body color is suppressed and high emission intensity is obtained. If the amount of F in the γ-AlON phosphor containing the composition represented by the formula (I) is less than 160 ppm by mass, the half-value width of the emission peak in the emission spectrum of the γ-AlON phosphor is kept narrow. The color purity is high. Therefore, when the light emitting device using the γ-AlON phosphor according to the present invention is used as the backlight source of the liquid crystal display device, the liquid crystal display device can reproduce a wide range of colors on the chromaticity coordinates.

  In the γ-AlON phosphor containing the composition represented by the formula (I), the half width of the emission peak in the emission spectrum obtained by photoexcitation in the near ultraviolet to blue region is preferably in the range of 25 nm to 50 nm. More preferably, it is in the range of 25 nm or more and 45 nm or less, and further preferably in the range of 25 nm or more and 40 nm or less. If the half width in the emission spectrum of the γ-AlON phosphor containing the composition represented by the formula (I) is in the range of 25 nm or more and 50 nm or less, the color purity is high, and the γ-AlON phosphor according to the present invention is used. When the light emitting device used is a backlight light source of a liquid crystal display device, the liquid crystal display device can reproduce a wide range of colors on chromaticity coordinates.

The γ-AlON phosphor obtained by the manufacturing method according to the first embodiment or the γ-AlON phosphor according to the second embodiment is combined with an LED or LD light-emitting element, whereby excitation light emitted from the light-emitting element. Thus, it is possible to constitute a light emitting device that emits light having a desired emission peak wavelength and emits mixed color light including light from the light emitting element and light wavelength-converted by the γ-AlON phosphor. As the light-emitting element, for example, a light-emitting element that emits light within a wavelength range of 350 nm to 485 nm can be used. As the light emitting element, for example, a semiconductor light emitting element using a nitride semiconductor (In _X Al _Y Ga _1- XYN, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) can be used. By using a semiconductor light emitting element as an excitation light source, it is possible to obtain a stable light emitting device with high efficiency, high output linearity with respect to input, and strong mechanical shock.

The γ-AlON phosphor can be used in combination with another phosphor having an emission peak wavelength different from that of the γ-AlON phosphor. Any phosphor other than the γ-AlON phosphor may be any phosphor that can absorb light in the near ultraviolet to blue region and convert the wavelength of light to a wavelength different from that of the γ-AlON phosphor. Examples of the phosphor other than the γ-AlON phosphor include (Ca, Sr, Ba) ₂ SiO ₄ : Eu, (Ca, Sr, Ba) ₈ MgSi ₄ O ₁₆ (F, Cl, Br) ₂ : Eu, Si _6-z Al _z O _z N _8-z : Eu (0 <z ≦ 4.2), (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, (Lu, Y, Gd, Lu) _{3 (Ga, Al) 5 O 12} : Ce, (La, Y, Gd) 3 Si 6 N 11: Ce, Ca 3 Sc 2 Si 3 O 12: Ce, CaSc 4 O 4: Ce, K 2 (Si, Ge , Ti) F ₆ : Mn, (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu, CaAlSiN ₃ : Eu, (Ca, Sr) AlSiN ₃ : Eu, (Sr, Ca) LiAl ₃ N ₄ : Eu, _{(Ca, Sr) 2 Mg 2} Li 2 Si 2 N 6: Eu, 3 _{5MgO · 0.5MgF 2 · GeO 2:} Mn , and the like. In the present specification, in the formula representing the composition of the phosphor, the plurality of elements described by being separated by a comma (,) includes at least one element among the plurality of elements in the composition. means. Further, in the present specification, in the formula representing the phosphor composition, the element before the colon (:) represents the element constituting the host crystal and its molar ratio, and the element after the colon (:) represents the activation element.

  Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples.

Production Examples 1 to 3
Preparation of the first mixture Manganese carbonate powder (MnCO ₃ ), lithium carbonate powder (Li ₂ CO ₃ ), magnesium oxide (MgO), aluminum oxide powder (Al ₂ O ₃ ) and aluminum nitride powder (AlN) are excluded from fluorine The first mixture is weighed so as to have a mass ratio of each compound shown in Table 1 with respect to the total amount (100% by mass), and mixed for 15 minutes or more using an aluminum oxide mortar and pestle. Got. Table 1 shows the fluorine content in the first mixture measured by the method described later.

First heat treatment The obtained first mixture was filled in a boron nitride crucible, capped, and subjected to a first heat treatment at 0.92 MPa in a nitrogen atmosphere (nitrogen gas 100% by volume) at 1850 ° C. for 4 hours. The first fired products 1 to 3 were obtained. The obtained first fired products 1 to 3 were sufficiently pulverized with an aluminum oxide mortar and pestle, and the average particle diameter D1 of the first fired products 1 to 3 after pulverization was measured.

Content of fluorine in the first mixture (mass ppm)
The fluorine content (mass ppm) in the first mixture is obtained by calculating the fluorine content in each compound contained in the first mixture, and summing the fluorine content in each compound contained in the first mixture. The fluorine content in the first mixture was calculated. The fluorine content in manganese carbonate, lithium carbonate, and magnesium oxide was measured using a measuring device (trade name: IM-40S, manufactured by Toa DKK Corporation) using an ion electrode method. The fluorine content in aluminum oxide and aluminum nitride was measured using ion chromatography (trade name: ICS 1500 type, manufactured by Dionex).

Measurement of average particle diameter (D1) About each 1st baked product after grinding | pulverization using Fisher Sub-Sieve Sizer Model 95 (made by Fisher Scientific), in the environment of air temperature 25 degreeC and humidity 70% RH, 1 cm < ³ >. A sample of a minute was weighed and packed in a special tubular container, then dry air at a constant pressure was flowed, the specific surface area was read from the differential pressure, and the average particle diameter D1 of the first fired product was calculated by the FSSS method. The results are shown in Table 1 or Table 4.

Comparative Examples 1, 3,
The obtained first fired product 1 of Production Example 1 was used as the γ-AlON phosphor of Comparative Example 1.
The obtained first fired product 2 of Production Example 2 was used as the γ-AlON phosphor of Comparative Example 3.

Examples 1 to 3, 7 and Comparative Examples 2, 7, 8
Preparation of Second Mixture Each first fired product 1, 2 and 3 after grinding, manganese carbonate powder (MnCO ₃ ), lithium carbonate powder (Li ₂ CO ₃ ), magnesium oxide (MgO), aluminum oxide powder (Al ₂ O ₃ ) and aluminum nitride powder (AlN) are weighed so as to be the mass ratio of the first fired product and each compound shown in Table 2 with respect to the total amount (100% by mass) of the first mixture excluding fluorine. Using an aluminum oxide mortar and pestle, the mixture was mixed for 15 minutes or more to obtain a second mixture.

Comparative Examples 4 to 6
Preparation of second mixture Each first fired product 2 after pulverization, manganese carbonate powder (MnCO ₃ ) or manganese fluoride powder (MnF ₂ ), lithium carbonate powder (Li ₂ CO ₃ ), or lithium fluoride powder (LiF) , Magnesium oxide (MgO), aluminum oxide powder (Al ₂ O ₃ ), and aluminum nitride powder (AlN) with respect to the total amount (100 mass%) of the first mixture excluding fluorine, the first firing shown in Table 2 The mixture was weighed so as to have a mass ratio of the product and each compound, and mixed for 15 minutes or more using an aluminum oxide mortar and pestle to obtain a second mixture.

Second heat treatment Each of the obtained second mixtures was filled in a boron nitride crucible, capped, and subjected to a second heat treatment at 0.92 MPa in a nitrogen atmosphere (nitrogen gas 100% by volume) at 1850 ° C. for 4 hours. To obtain a second fired product. The obtained second fired product was sufficiently pulverized with an aluminum oxide mortar and pestle. The obtained second fired products were used as the γ-AlON phosphors of Examples 1 to 3, 7 and Comparative Examples 2, 4 to 8.

Examples 4 to 6
Annealing treatment Each of the second fired products obtained as the γ-AlON phosphors of Examples 1 to 3 was subjected to an annealing treatment. Each second fired product obtained as the γ-AlON phosphor of Examples 1 to 3 was filled in a boron nitride crucible, covered, and atmospheric pressure (0.1 MPa), a mixed gas atmosphere of argon and hydrogen (Ar = 66). Annealing was performed at 1200 ° C. for 2 hours in an amount of 0.6 vol% and H ₂ being 33.3 vol%. The obtained annealed product was sufficiently pulverized using an aluminum oxide mortar and pestle. The obtained annealed product was used as each γ-AlON phosphor of Examples 4 to 6.

Fluorine content in the second mixture (% by mass)
The fluorine content in the second mixture is obtained by calculating the fluorine content in each compound contained in the second mixture, and adding the fluorine content in each compound contained in the second mixture. The total content of was 100% by mass, and the fluorine content (% by mass) in the second mixture was calculated. The fluorine content in manganese carbonate, lithium carbonate, and magnesium oxide was measured using a measuring device (trade name: IM-40S, manufactured by Toa DKK Corporation) using an ion electrode method. The fluorine content in aluminum oxide and aluminum nitride was measured using ion chromatography (trade name: ICS 1500 type, manufactured by Dionex). For manganese fluoride (MnF ₂ ) and lithium fluoride (LiF), the fluorine content was calculated from the molar ratio of fluorine in each compound. The results are shown in Table 2.

Composition analysis The γ-AlON phosphors of the examples and comparative examples are included in the γ-AlON phosphor by ICP emission spectroscopic analysis using an inductively coupled plasma emission analyzer (manufactured by Perkin Elmer). The composition analysis of each element excluding fluorine was conducted. For Mn, Mg, Li, Al, O, and N, the total ratio of each element was set to 1, and the molar ratio of each element was calculated. The results are shown in Table 3. The γ-AlON phosphors of Comparative Examples 5 and 6 were not subjected to composition analysis of the γ-AlON phosphor because the fluorine content measured by the measurement method described later exceeded 150 ppm.

Fluorine content of γ-AlON phosphor (mass ppm)
The fluorine content in the γ-AlON phosphors of Example 7 and Comparative Examples 3 to 6 was measured using ion chromatography (trade name: ICS 1500 type, manufactured by Dionex). The results are shown in Table 3.

Measurement of average particle size (D2, D3) For the second baked product and the annealed product, the average particle size of the second baked product by the FSSS method using the same apparatus and method as the measurement of the average particle size D1 of the first baked product D2 and the average particle diameter D3 of the annealed product were calculated. The results are shown in Table 4.

Evaluation of luminous characteristics Luminous peak wavelength and relative luminous intensity The luminous characteristics of the γ-AlON phosphors of the examples and comparative examples were measured. Using a quantum efficiency measuring device (trade name: QE-2000, manufactured by Otsuka Electronics Co., Ltd.), each phosphor was irradiated with light having an excitation wavelength of 450 nm, and an emission spectrum at room temperature (25 ± 5 ° C.) was measured. The emission peak wavelength and emission intensity (%) of the emission spectrum of each γ-AlON phosphor obtained were determined. For the γ-AlON phosphors of Examples 1 to 6, Comparative Example 2, and Comparative Examples 7 and 8, the relative emission intensity was determined with the emission intensity of the γ-AlON phosphor of Comparative Example 1 being 100%. For the γ-AlON phosphors of Example 7 and Comparative Examples 4 to 6, the relative emission intensity was determined with the emission intensity of the γ-AlON phosphor of Comparative Example 3 being 100%. The results are shown in Table 4.

Half-value width About the γ-AlON phosphors of the examples and comparative examples, the half-value width (FWHM) of the obtained emission spectrum was determined. The full width at half maximum of the phosphor is the wavelength width of the emission peak showing the emission intensity of 50% of the maximum emission intensity in the emission spectrum. The results are shown in Table 4.

Reflectance (%) and absorption rate (%)
About the γ-AlON phosphor of each example and comparative example, a halogen serving as an excitation light source at room temperature (25 ± 5 ° C.) using a spectrofluorometer (F-4500, manufactured by Hitachi High-Technologies Corporation) Light from the lamp was irradiated to each γ-AlON phosphor serving as a sample, and the reflected light at 450 nm and the reflected light at 730 nm were measured by scanning in accordance with the wavelengths of the spectrometers on the excitation side and the phosphor side. The ratio of the reflected light at 730 nm to the light having a wavelength of 450 nm was measured as the reflectance (%) at 730 nm with reference to the reflectance of calcium hydrogen phosphate (CaHPO ₄ ). The ratio of the reflected light at 450 nm to the light with a wavelength of 450 nm was made 450% reflectance (%) based on the reflectance of calcium hydrogen phosphate (CaHPO ₄ ), and the reflectance (%) from 450% was reduced to 100%. The value was defined as the absorption rate (%) at 450 nm. The results are shown in Table 4.

  In Examples 1 to 3, the second fired product obtained by performing the second heat treatment on the mixture containing the first fired product in excess of 20% by mass and 80% by mass or less was used as a γ-AlON phosphor. In the γ-AlON phosphors of Examples 1 to 3, the first fired product became a seed crystal, the crystal growth was promoted, and the average particle diameter D2 measured by the FSSS method was as large as 16.0 μm or more. The γ-AlON phosphors of Examples 1 to 3 had a half-value width narrower than that of Comparative Example 1 and higher relative emission intensity than that of Comparative Example 1. The γ-AlON phosphors of Examples 1 to 3 had a higher absorption rate of 450 nm than the γ-AlON phosphor of Comparative Example 1, and efficiently absorbed light in the blue region from near ultraviolet to emit green light. . Since the γ-AlON phosphor of Examples 1 to 3 has a larger particle size than that of the phosphor of Comparative Example 1 or 2, and has a higher absorption rate at 450 nm, the reflectance at a wavelength of 730 nm is the phosphor of Comparative Example 1 or 2. It was slightly lower than. As shown in Examples 1 to 3, when the total content of aluminum oxide and aluminum nitride in the second mixture was 15% by mass or more, crystal growth was promoted using the first fired product as a seed crystal.

  In the γ-AlON phosphor of Comparative Example 2, since the first fired product contained in the second mixture is as small as 20% by mass, crystal growth from the seed crystal is not promoted, and the average particle size D2 of the second fired product is It was as small as less than 16.0 μm, and the relative emission intensity was lower than that of the γ-AlON phosphor of Comparative Example 1 that was not subjected to the second heat treatment.

  In Examples 4 to 6, an annealed product obtained by further subjecting the second fired product used as the γ-AlON phosphor in Examples 1 to 3 to an annealing treatment was used as a γ-AlON phosphor. In the γ-AlON phosphors of Examples 4 to 6, the Mn other than divalent contained in the second fired product was reduced by the annealing treatment, and the ratio of the divalent Mn in the γ-AlON phosphor was increased. More than each γ-AlON phosphor of Examples 1 to 3 made of the second fired product that is not annealed and has the same amount of the first fired product in the second mixture. The relative light emission intensity increased.

  The γ-AlON phosphor of Example 7 does not contain fluoride as a raw material or flux in the second mixture, the fluorine content in the γ-AlON phosphor is 150 mass ppm or less, and the formula ( In the composition represented by I), when the total molar ratio of the elements constituting the γ-AlON phosphor excluding fluorine is 1, the numerical value of the variable g indicating the molar ratio of fluorine is 0 or more and 0.00016 or less. The numerical value of was satisfied. The γ-AlON phosphor of Example 7 had higher emission intensity than the γ-AlON phosphor of Comparative Example 3 that was not subjected to the second heat treatment.

  The γ-AlON phosphors of Comparative Examples 4 to 6 contain fluoride in the second mixture, and due to the effect of the fluoride flux, the average particle diameter D2 of the γ-AlON phosphor made of the second fired product is Although it was larger than the γ-AlON phosphor of Example 7, the relative emission intensity was lower than that of the γ-AlON phosphor of Example 7. Further, the γ-AlON phosphors of Comparative Examples 4 to 6 have a fluorine content larger than 150 ppm by mass, and constitute a γ-AlON phosphor excluding fluorine in the composition represented by the formula (I). When the total molar ratio of the elements was 1, the numerical value of the variable g indicating the fluorine molar ratio did not satisfy the numerical value of 0 or more and 0.00016 or less. From this result, it was speculated that the γ-AlON phosphors of Comparative Examples 4 to 6 were incorporated with fluorine in the crystal structure and the crystal structure was unstable. Compared with the γ-AlON phosphor of Example 7, the γ-AlON phosphors of Comparative Examples 4 to 6 had a tendency that the emission peak wavelength shifted to the longer wavelength side or the half-value width became wider. As compared with the γ-AlON phosphor of Example 7, the emission peak wavelength of the γ-AlON phosphor of Comparative Example 6 having a large amount of fluorine was clearly shifted to the longer wavelength side, and the half-value width was wide.

  In the γ-AlON phosphors of Comparative Examples 7 and 8, the content of the first fired product in the second mixture is larger than 82% by mass, and the amount of the compound that is a raw material contained in the second mixture is relatively large. The crystal growth was not promoted, and the particle size D2 of the second fired product was less than 16.0 μm.

  A γ-AlON phosphor according to an embodiment of the present invention has high emission intensity by light excitation in the near ultraviolet to blue region, and a light-emitting device using the γ-AlON phosphor includes general illumination, in-vehicle illumination, and display. It can be used in a wide range of fields such as backlights for liquid crystals, traffic lights, and lighting switches.

Claims (8)

A first mixture containing a compound containing Mn, a compound containing Li, a compound containing Mg, aluminum oxide, and aluminum nitride, and the amount of fluorine is 150 mass ppm or less with respect to the total amount of the first mixture excluding fluorine. Preparing a first heat treatment to the first mixture, obtaining a first fired product having an average particle diameter D1 of 10.0 μm or more measured by the Fischer sub-sieve sizers method;
The first baked product, the compound containing Mn, the compound containing Li, the compound containing Mg, the aluminum oxide, and the aluminum nitride, and the amount of fluorine is 150 mass ppm with respect to the total amount of the second mixture excluding fluorine. A second mixture is prepared, wherein the second mixture contains the first fired product in an amount of more than 20% by mass and 82% by mass or less based on the total amount of the second mixture excluding fluorine; A method for producing a γ-AlON phosphor, comprising: subjecting a second mixture to a second heat treatment, and obtaining a second fired product having an average particle diameter D2 of 16.0 μm or more as measured by a Fischer sub-sieve sizer method.   2. The method for producing a γ-AlON phosphor according to claim 1, wherein at least one of the temperature of the first heat treatment or the temperature of the second heat treatment is in a range of 1600 ° C. or more and 1900 ° C. or less.   The manufacturing method of (gamma) -AlON fluorescent substance of Claim 1 or 2 including the process of annealing-treating said 2nd baked product and obtaining an annealed product.   The method for producing a γ-AlON phosphor according to claim 3, wherein a temperature of the annealing treatment is in a range of 1100 ° C to 1500 ° C.   5. The second mixture according to claim 1, wherein the second mixture contains a total of 15 mass% or more of the aluminum oxide and the aluminum nitride with respect to the total amount of the second mixture excluding fluorine. A method for producing a γ-AlON phosphor.   The said 2nd mixture contains 40 mass% or more and 80 mass% or less of said 1st baking products with respect to the whole quantity of the said 2nd mixture except a fluorine, The any one of Claim 1 to 5 A method for producing a γ-AlON phosphor. The method for producing a γ-AlON phosphor according to any one of claims 1 to 6, wherein the second fired product includes a composition represented by the following formula (I).
_{Mn a Mg b Li c Al d} O e N f F g (I)
(In the formula (I), a, b, c, d, e, f and g are 0.005 ≦ a ≦ 0.02, 0.01 ≦ b ≦ 0.035, 0 when a + b + c + d + e + f = 1. .01 ≦ c ≦ 0.04, 0.3 ≦ d ≦ 0.45, 0.4 ≦ e ≦ 0.6, 0.03 ≦ f ≦ 0.06, 0 ≦ g ≦ 0.00016 is there.) A γ-AlON phosphor containing a composition represented by the following formula (I) and having an average particle size of 16.0 μm or more as measured by the Fuscher sub-sieve sizers method.
_{Mn a Mg b Li c Al d} O e N f F g (I)
(In the formula (I), a, b, c, d, e, f and g are 0.005 ≦ a ≦ 0.02, 0.01 ≦ b ≦ 0.035, 0 when a + b + c + d + e + f = 1. .01 ≦ c ≦ 0.04, 0.3 ≦ d ≦ 0.45, 0.4 ≦ e ≦ 0.6, 0.03 ≦ f ≦ 0.06, 0 ≦ g ≦ 0.00016 is there.)

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