JP6974758B2 - Chlorosilicate phosphor, its manufacturing method and light emitting device - Google Patents

Description

The present invention relates to a chlorosilicate fluorescent substance, a method for producing the same, and a light emitting device.

By combining a light source and a wavelength conversion member that is excited by the light from this light source and can emit light with a hue different from that of the light source, it is possible to emit light of various hues by the principle of light color mixing. A light source has been developed. For example, a light emitting device that combines a light emitting element such as a light emitting diode (hereinafter referred to as "LED") and a phosphor that is a wavelength conversion member corresponds to visible light from ultraviolet light emitted from the light emitting element. When each phosphor that emits red, green, and blue light is excited by the light on the short wavelength side, the three primary colors of light, red, green, and blue, are mixed to obtain white light.

As a fluorescent substance that emits light from yellow to green, for example, Patent Document 1 discloses a silicate fluorescent substance activated by Eu.

U.S. Patent Application Publication No. 2006/0027785

Among the silicate phosphors, as a typical fluorescent substance that emits green light, for example, calcium magnesium chlorosilicate activated by Eu (generally, the composition formula is expressed as Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu. ) (Hereinafter referred to as "chlorosilicate phosphor"). The green phosphor has a large influence on the luminous flux of the light emitting device, and in order to further increase the luminous flux of the light emitting device, a chlorosilicate phosphor having higher luminous efficiency is required.
Therefore, it is an object of the present invention to provide a phosphor having high luminous efficiency, a method for producing the same, and a light emitting device.

The present invention includes the following aspects.
The first aspect of the present invention has a chemical composition containing Ca, Eu, Mg, Si, O, and Cl, and when the molar ratio of Si in 1 mol of the chemical composition is 4, Ca is mol. The ratio is in the range of 7.0 or more and 7.94 or less, Eu is in the range of 0.01 or more and 1.0 or less in molar ratio, and the total of Ca and Eu is in the range of 7.70 or more and 7.95 or less in molar ratio. Among them, it is a chlorosilicate phosphor containing Mg in a molar ratio of 0.9 or more and 1.1 or less, and Cl in a molar ratio of more than 1.90 and 2.00 or less.

A second aspect of the present invention is a light emitting device including a light source having a emission peak wavelength in the range of 250 nm or more and 485 nm or less, and the chlorosilicate phosphor.

A third aspect of the present invention prepares a compound containing Ca, a compound containing Eu, a compound containing Mg, a compound containing Si, and a compound containing Cl, and contains a compound containing Eu and a compound containing Mg. At least one compound selected from the group consisting of the compound and the compound containing Si may be an oxide, and the compound containing Cl may contain Ca or Mg.
When the molar ratio of Ca in the compound containing Si is 4 mol, the molar ratio of Ca is in the range of 7 or more and 8.2 or less, the molar ratio of Eu is in the range of 0.01 or more and 1.1 or less, and the mole of Mg is used. The ratio is in the range of 0.9 or more and 1.1 or less, the total molar ratio of Ca and Eu is in the range of 8.05 or more and 8.25 or less, and the molar ratio of Cl is in the range of 2.0 or more and 3.0 or less. A method for producing a phosphor, which comprises weighing and mixing each compound so as to obtain a raw material mixture, firing the raw material mixture, and obtaining a chlorosilicate phosphor.

According to the above-described embodiment, it is possible to provide a chlorosilicate fluorescent substance having high luminous efficiency, a method for producing the same, and a light emitting device.

FIG. 1 is a schematic cross-sectional view showing an example of a light emitting device. FIG. 2 is a diagram showing emission spectra of the phosphors of Example 3 and Comparative Example 1. FIG. 3 is a diagram showing emission spectra of the phosphors of Example 6 and Comparative Example 5.

Hereinafter, the chlorosilicate fluorescent substance according to the present disclosure, a method for producing the same, and a light emitting device will be described based on the embodiments. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following phosphors, manufacturing methods thereof, and light emitting devices. The relationship between the color name and the chromaticity coordinate, the relationship between the wavelength range of light and the color name of monochromatic light, etc., follow JIS Z8110.

Fluorescent material The phosphor has a chemical composition containing Ca, Eu, Mg, Si, O, and Cl, and when the molar ratio of Si in 1 mol of the chemical composition is 4, Ca is 7 in molar ratio. Within the range of 0.0 or more and 7.94 or less, Eu in the range of 0.01 or more and 1.0 or less in molar ratio, the total of Ca and Eu in the range of 7.70 or more and 7.95 or less in molar ratio, Mg Is a chlorosilicate phosphor containing a molar ratio of 0.9 or more and 1.1 or less, and Cl in a molar ratio of more than 1.90 and 2.00 or less.

The fluorescent substance is preferably a chlorosilicate fluorescent substance having a chemical composition represented by the following formula (I).
Ca _x Eu _y Mg _z Si ₄ O _a Cl _b (I)
(In the formula (I), a, b, x, y and z are 7.0 ≦ x ≦ 7.94, 0.01 ≦ y ≦ 1.0, 7.70 ≦ x + y ≦ 7.95, respectively. It is a number that satisfies 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, and 1.90 <b ≦ 2.00.)

In the formula (I), the variables a, b, x, y and z represent the molar ratios of the O element, Cl element, Ca element, Eu element and Mg element constituting the chlorosilicate phosphor. The term "molar ratio" represents the molar amount of each element in one mole of the chemical composition of the phosphor.

The theoretical composition of the chlorosilicate phosphor is _{represented by Ca 8} Mg (SiO ₄ ) ₄ Cl ₂ : Eu. In a chlorosilicate phosphor having a chemical composition containing Ca, Eu, Mg, Si, O, and Cl, Eu is an activating element and is replaced with a part of Ca sites in the parent crystal constituting the fluorophore. it is conceivable that. In the composition of the chlorosilicate phosphor, the total molar ratio of Ca and Eu is preferably close to 8, which is the molar ratio of Ca in 1 mol of the theoretical composition of chlorosilicate, from the viewpoint of the stability of the crystal structure. Was speculated. However, we found that if the total molar ratio of Ca and Eu in the chlorosilicate phosphor is greater than 8 or 8, which is the molar ratio of Ca in 1 mol of theoretical composition, Ca binds to the silicate. It has been found that the double phase of calcium silicate is likely to be generated, and the luminescence efficiency is rather lowered. For chlorosilicate phosphors, the maximum value of the total of Ca and Eu in 1 mol of chemical composition is 7.95 or less, which is smaller than 8 which is the molar ratio of Ca in 1 mol of theoretical composition of chlorosilicate. The formation of multiple phases of calcium silicate is suppressed, and the luminous efficiency can be increased. The chlorosilicate phosphor contains Ca and Eu in the range of 7.70 or more and 7.95 or less in the total molar ratio of Ca and Eu when the molar ratio of Si in 1 mol of the chemical composition is 4. It is preferably contained in the range of 7.80 or more and 7.95 or less. In the chlorosilicate phosphor having a chemical composition represented by the formula (I), the total of the variable x representing the molar ratio of Ca and the variable y representing the molar ratio of Eu is 7.70 or more and 7.95 or less (7. It is within the range of 70 ≦ x + y ≦ 7.95), preferably within the range of 7.80 or more and 7.95 or less (7.80 ≦ x + y ≦ 7.95). When the total amount of Ca and Eu in 1 mol of the chemical composition of the chlorosilicate phosphor is 7.70 or more in terms of molar ratio, a stable crystal structure can be maintained and the luminous efficiency can be increased.

The chlorosilicate fluorescent substance contains Cl constituting the parent crystal in a molar ratio of more than 1.90 and not more than 2.00. In the theoretical composition of chlorosilicate, if Cl is smaller than 1.90 in molar ratio, defects may occur in the mother crystal and the luminous efficiency may decrease. If the chlorosilicate phosphor contains Cl constituting the mother crystal in a molar ratio of more than 2.00, the mother crystal may be defective and the luminous efficiency may be lowered. For the stability of the crystal structure, the chlorosilicate fluorophore contains Cl constituting the parent crystal in a molar ratio of more than 1.90 and not more than 2.00, preferably 1.95 or more and 2.00 or less. Including in the range of less than. In the chlorosilicate phosphor having the chemical composition represented by the formula (I), the variable b representing the molar ratio of Cl constituting the mother crystal exceeds 1.90 and is 2.00 or less (1.90 <b ≦). It is in the range of 2.00), preferably in the range of 1.95 or more and less than 2.00 (1.95 ≦ b <2.00).

The chlorosilicate phosphor contains Ca in 1 mol of the chemical composition in the range of 7.00 or more and 7.94 or less, preferably in the range of 7.20 or more and 7.90 or less in order to enhance the luminous efficiency. , More preferably in the range of 7.30 or more and 7.80 or less, and even more preferably in the range of 7.40 or more and 7.70 or less. The fluorescent substance having the chemical composition represented by the formula (I) has a variable x representing the molar ratio of Ca in the range of 7.00 or more and 7.94 or less (7.00 ≦ x ≦ 7.94). It is preferably in the range of 7.20 or more and 7.90 or less (7.20 ≦ x ≦ 7.90), and more preferably 7.30 or more and 7.80 or less (7.30 ≦ x ≦ 7.80). It is within the range, and more preferably within the range of 7.40 or more and 7.70 or less (7.40 ≦ x ≦ 7.70).

The chlorosilicate phosphor contains Eu, which is an activating element, in a molar ratio of 0.01 or more and 1.00 or less, preferably 0.05 or more and 0.90 or less, and more preferably 0.10. It is included in the range of 0.80 or less, more preferably 0.15 or more and 0.60 or less. If the chlorosilicate phosphor contains Eu, which is an activating element, in the range of 0.01 or more and 1.00 or less in terms of molar ratio, the chlorosilicate phosphor absorbs the light from the light source and emits Eu. Is excited, and the wavelength of the light of the light source can be converted by the excitation energy. If the chlorosilicate phosphor contains Eu in the molar ratio range of 0.01 or more and 1.00 or less, it absorbs light from a light source having an emission peak wavelength in the range of 250 nm or more and 485 nm or less, for example. Therefore, light having an emission peak wavelength within the range of 495 nm or more and 548 nm or less can be emitted. Further, as long as the chlorosilicate phosphor contains Eu in the range of 0.01 or more and 1.00 or less in molar ratio, the luminous efficiency can be increased without lowering the luminous efficiency due to concentration quenching or the like. .. The chlorosilicate phosphor having the chemical composition represented by the formula (I) has a variable y representing the molar ratio of Eu within the range of 0.01 or more and 1.00 or less (0.01 ≦ y ≦ 1.00). It is preferably in the range of 0.05 or more and 0.90 or less (0.05 ≦ y ≦ 0.90), and more preferably 0.10 or more and 0.80 or less (0.10 ≦ y ≦ 0. It is within the range of 80), and more preferably within the range of 0.15 or more and 0.60 or less (0.15 ≦ y ≦ 0.60).

In order to obtain a stable crystal structure, the chlorosilicate phosphor contains Mg in a molar ratio of 0.90 or more and 1.10 or less, preferably 0.95 or more and 1.05 or less. Included within the range of. In order to obtain a stable crystal structure, the phosphor having the chemical composition represented by the formula (I) has a variable z representing the molar ratio of Mg in the composition of 0.90 or more and 1.10 or less (0.90 ≦ z). It is within the range of ≦ 1.10), preferably within the range of 0.95 or more and 1.05 or less (0.95 ≦ z ≦ 1.05).

In order to obtain a stable crystal structure, the chlorosilicate phosphor contains O in a molar ratio of 15.60 or more and 16.10 or less, preferably 15.73 or more and 16.05 or less. It is contained within the range of, and more preferably within the range of 15.78 or more and 16.00 or less. In the chlorosilicate phosphor having the chemical composition represented by the formula (I), in order to obtain a stable crystal structure, the variable a representing the molar ratio of O in the composition is 15.60 or more and 16.10 or less (15.60). It is within the range of ≦ a ≦ 16.10), preferably within the range of 15.73 or more and 16.05 or less (15.73 ≦ a ≦ 16.05), and more preferably 15.78 or more and 16.00. It is within the range of the following (15.78 ≦ a ≦ 16.00). In the chemical composition represented by the formula (I), the variable a representing the molar ratio of O is the following formula (from the variables x, y, z and b representing the molar ratio of each element constituting the phosphor other than O). It can be calculated by 1).
a = x + y + z + (4 × 2)-(b ÷ 2) (1)

The phosphor has a chlorosilicate phosphor as a phosphor core, and at least one oxide selected from the group consisting _{of Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO _{2 is adhered to the surface of the phosphor core.} It is preferable to have.
Chlorosilicate fluorophores contain chlorine in their composition and therefore tend to deteriorate in hot and humid environments. The phosphor has a high temperature due to attachment of at least one oxide selected from the group consisting of _{Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ to the surface of the phosphor core made of a chlorosilicate phosphor. In a high humidity environment, deterioration of the surface can be suppressed and the durability of the light emitting device using the chlorosilicate phosphor can be improved.

As a method for adhering at least one oxide selected from the group consisting _{of Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ to the surface of a phosphor core made of a chlorosilicate phosphor, for example, Al, Si. , Zr and Ti, a method of forming by a sol-gel method using a solution containing a metal alkoxide containing at least one metal element selected from the group. The oxide attached to the surface of the phosphor core preferably adheres to the surface of the phosphor core in the form of a film in order to suppress deterioration of the phosphor core, and forms a film on the entire surface of the surface of the phosphor core. It is more preferable that it adheres.

The oxide attached to the surface of the phosphor core is preferably in the range of 2 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the phosphor core in terms of metal contained in the oxide, and is preferably 3 parts by mass. It is more preferably in the range of 4 parts by mass or more and 25 parts by mass or less, and further preferably in the range of 4 parts by mass or more and 24 parts by mass or less. The oxide attached to the surface of the phosphor core may be in the range of 2 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the phosphor core in terms of metal contained in the oxide, and is 3 parts by mass. It may be in the range of 10 parts or more and 10 parts by mass or less. The metal contained in the oxide attached to the surface of the phosphor core is specifically at least one selected from the group consisting of Al, Si, Zr and Ti. If the oxide attached to the surface of the phosphor core is within the range of 2 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the phosphor core in terms of the metal contained in the oxide, the phosphor core Oxides can be attached to the surface in the form of a film, and even in a high temperature and high humidity environment, deterioration of the surface of the chlorosilicate fluorescent substance is suppressed, and the durability of the light emitting device using the chlorosilicate phosphor is improved. be able to. If the oxide attached to the surface of the phosphor core is within the range of 2 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the phosphor core in terms of metal contained in the oxide, a relatively thin film is formed. Oxides can be attached to the surface of the surface of the phosphor core, and the particle size of the chlorosilicate phosphor can be reduced. By reducing the particle size of the chlorosilicate phosphor in which the oxide is adhered to the surface of the phosphor core, the chlorosilicate phosphor can be unevenly distributed on the light emitting side in the fluorescent member. As a result, the light wavelength-converted by the chlorosilicate phosphor can be easily taken out from the light emitting device, and the relative luminous flux of the light emitting device can be increased.

The particle size of the chlorosilicate phosphor is preferably 2.0 μm or more, more preferably 4.0 μm or more, still more preferably 5.0 μm or more, preferably 30.0 μm or less, and more preferably 25 μm. It is 0 μm or less. When the particle size of the chlorosilicate phosphor is in the range of 2.0 μm or more and 30.0 μm or less, the conversion efficiency of light from the light source becomes higher, and the luminous efficiency of the light emitting device using the chlorosilicate phosphor is high. can do. Further, when the particle size of the chlorosilicate phosphor is 30.0 μm or less, the workability in the manufacturing process of the light emitting device can be improved. The particle size of the chlorosilicate phosphor is a particle size at which the cumulative volume frequency from the small diameter side measured by a laser diffraction type particle size distribution measuring device reaches 50% (hereinafter, also referred to as "volume median diameter"). be. As the laser diffraction type particle size distribution measuring device, for example, MASTER SIDER 3000 manufactured by MALVERN can be used.

The chlorosilicate phosphor may contain at least one element selected from the group consisting of Sr, Ba and Al, and the chlorosilicate phosphor may contain at least one element selected from the group consisting of Sr, Ba and Al. It may be contained in a ratio of 360 mass ppm or less with respect to 100 mass% of the chlorosilicate phosphor. Sr and Ba are elements similar to Ca constituting the composition of the chlorosilicate phosphor, are contained in the compound containing Ca which is the raw material of the chlorosilicate phosphor, and may be mixed in the phosphor. Further, Al may be contained in a compound containing Si, which is a raw material of a chlorosilicate phosphor, or may be used as a material of a dispersion medium used in the production of a phosphor, and may be used as a material for a phosphor. It may be mixed during manufacturing. The chlorosilicate phosphor has a ratio of 360 mass ppm or less even when it contains at least one element selected from Sr, Ba and Al, which are elements other than the elements constituting the composition. Luminous efficiency does not decrease. When the chlorosilicate phosphor contains two or more elements selected from the group consisting of Sr, Ba and Al, the total of the two or more elements is 360 mass% with respect to 100 mass% of the phosphor. It may be ppm or less. Even if the chlorosilicate phosphor contains at least one element selected from the group consisting of Sr, Ba and Al, the content of the element is 360% by mass or less with respect to 100% by mass of the phosphor. If so, high luminous efficiency can be maintained. The content of at least one element selected from the group consisting of Sr, Ba and Al in the chlorosilicate phosphor may be 350 mass ppm or less, 300 mass ppm or less, or 250 mass ppm or less. It may be ppm or less.

Method for producing a phosphor In the method for producing a phosphor, a compound containing Ca, a compound containing Eu, a compound containing Mg, a compound containing Si, and a compound containing Cl are prepared, and a compound containing Eu, At least one compound selected from the group consisting of a compound containing Mg and a compound containing Si is an oxide, and the compound containing Cl may contain Ca or Mg, and Si in the compound containing Si may be used. When 4 mol, the molar ratio of Ca is in the range of 7 or more and 8.2 or less, the molar ratio of Eu is in the range of 0.01 or more and 1.1 or less, and the molar ratio of Mg is 0. The range is 9 or more and 1.1 or less, the total molar ratio of Ca and Eu is 8.05 or more and 8.25 or less, and the molar ratio of Cl is 2.0 or more and 3.0 or less. It includes weighing and mixing each compound so as to be within each of these ranges to obtain a raw material mixture, firing the raw material mixture, and obtaining a phosphor.

As the compound containing Ca, the compound containing Eu, and the compound containing Mg, a halogen salt, an oxide, a carbonate, a phosphate, a silicate or an ammonium salt containing each element can be used. As the compound containing Si, an oxide containing Si, a hydroxide, an acid nitrogen compound, a nitride compound, an imide compound, and an amide compound can be used. The compound containing Cl may be a chloride containing Ca or Mg. Specific examples of the compound containing Ca include CaF ₂ , CaCl ₂ , and CaCO ₃ . Examples of the compound containing Eu include an imide compound containing metal europium, Eu ₂ O ₃ , EuN, and Eu, and an amide compound containing Eu. Examples of the compound containing Mg include MgF ₂ , MgCl ₂ , MgO, and MgCO ₃ . Examples of the compound containing Si include simple substance Si, SiO ₂ , Si ₃ N ₄ , and Si (NH ₂ ) ₂ . Examples of the compound containing Cl include CaCl ₂ and MgCl ₂ .

When Si is 4 mol, the molar ratio of Ca is in the range of 7 or more and 8.2 or less, the molar ratio of Eu is in the range of 0.01 or more and 1.1 or less, and the total of Ca and Eu. The compound containing Ca and the compound containing Eu are weighed so that the molar ratio of Ca is in the range of 8.05 or more and 8.25 or less. By weighing the compound containing Ca and the compound containing Eu so as to have a molar ratio in the above range, the total molar ratio of Ca and Eu in the obtained phosphor is the molar ratio in the theoretical composition of chlorosilicate. The molar ratio can be a value close to a certain value 8 and not more than 8. By adjusting the total molar ratio of Ca and Eu in the obtained fluorescent substance, a fluorescent substance having high luminous efficiency can be produced without Ca binding to the silicate to form a double phase of calcium silicate. be able to. For compounds containing Ca, the molar ratio of Ca is preferably in the range of 7.2 or more and 8.1 or less, and more preferably in the range of 7.4 or more and 8.0 or less when Si is 4 mol. Weigh in, more preferably in the range of 7.5 or more and 7.9 or less. Further, in the compound containing Eu, when Si is 4 mol, the molar ratio of Eu is preferably in the range of 0.05 or more and 1.0 or less, and more preferably 0.10 or more and 0.9 or less. Weighing is performed so as to be within the range of, more preferably 0.12 or more and 0.8 or less. Further, the compound containing Ca and the compound containing Eu are weighed so that the total molar ratio of Ca and Eu is preferably in the range of 8.05 or more and 8.24 or less when Si is 4 mol. do.

In the compound containing Mg, the molar ratio of Mg is in the range of 0.9 or more and 1.1 or less when Si is 4 mol in order to obtain a phosphor having a stable crystal structure, preferably 0. Weigh so that it is within the range of 95 or more and 1.05 or less.

The compound containing Cl has a molar ratio of Cl of 2.0 or more and 3.0 or less, preferably 2.1 or more and 2.8 or less, when Si is 4 mol. More preferably, it is weighed so as to be in the range of 2.2 or more and 2.7 or less. When the molar ratio of Cl in 1 mol of the chemical composition contained in the obtained phosphor is as small as 1.90 or less, defects may occur in the mother crystal of the obtained phosphor, and it is easy to scatter when the raw material is heat-treated. It is preferable that a compound containing Cl is contained so as to have a molar ratio of 2 or more in the theoretical composition of chlorosilicate. When the compound containing Cl contains an element other than Cl that constitutes the chemical composition of the phosphor, the compound is weighed so that the molar ratio of each element constituting the chemical composition of the phosphor is within the above-mentioned molar ratio. It is preferable to do so.

Raw Material Mixture Each weighed compound is mixed wet or dry using a mixer to obtain a raw material mixture. As the mixer, in addition to ball mills usually used industrially, crushers such as vibration mills, roll mills, and jet mills can also be used. The specific surface area of the raw material can be increased by pulverizing the raw material. In addition, as the raw material, in order to keep the specific surface area of the particles within a certain range, a settling tank, a hydrocyclone, a wet separator such as a centrifuge, and a dry classifier such as a cyclone and an air separator, which are usually used industrially, are used. It can also be classified using.

The flux raw material mixture may contain flux. Since the raw material mixture contains a flux, the reaction between the raw materials is further promoted, and the solid phase reaction proceeds more uniformly, so that a calcined product used to obtain a phosphor having better emission characteristics is produced. be able to. For example, when the heat treatment for obtaining a fired product is in the temperature range of 1000 ° C. or higher and 1250 ° C. or lower, and a halide or the like is used as the flux, the temperature in this range is almost the same as the formation temperature of the liquid phase of the halide. Since they are the same, it is considered that the solid phase reaction between the raw materials proceeds more uniformly. As the halide used as the flux, rare earth metals such as cerium and europium, chlorides and fluorides of alkali metals can be used. The flux can be adjusted so that the element ratio of the cations contained in the flux is the composition of the calcined product to be obtained, and flak can be added as a part of the raw material of the phosphor, or the composition of the calcined product to be obtained can be obtained. After adding each raw material as described above, the flux can be added in the form of further addition.

When the raw material mixture contains flux, the flux component promotes reactivity, but if it is too much, the luminous efficiency of the obtained phosphor may decrease. Therefore, the content of the flux is preferably, for example, 10% by mass or less, and more preferably 5% by mass or less in the raw material mixture.

Firing The raw material mixture is placed in a crucible or boat of SiC, quartz, alumina, BN, etc. and fired in a furnace. By calcining the raw material mixture, a powder of the calcined product is obtained.

The firing temperature is preferably in the range of 1000 ° C. or higher and 1300 ° C. or lower, and more preferably in the range of 1100 ° C. or higher and 1250 ° C. or lower. If the firing temperature is within the range of 1000 ° C. or higher and 1300 ° C. or lower, the firing temperature is too high and the fired product does not decompose, and the fired product has a chemical composition containing Ca, Eu, Mg, Si, O, and Cl. Is obtained. As for the firing, the secondary firing may be performed after the primary firing, or a plurality of firings may be performed.

The firing time at one time is preferably 1 hour or more and 30 hours or less. It is also possible to fire by changing the temperature step by step at the time of one firing. For example, two-stage firing (multi-step firing) in which the first-stage firing is performed within the range of 800 ° C. or higher and 1000 ° C. or lower, and the temperature is gradually raised to perform the second-stage firing within the range of 1000 ° C. or higher and 1300 ° C. or lower. May be done.

The firing of the raw material mixture is preferably carried out in a reducing nitrogen atmosphere. The firing atmosphere is more preferably a nitrogen atmosphere containing reducing hydrogen gas. The firing atmosphere may be a reducing atmosphere using solid carbon in the atmospheric atmosphere.

By firing in an atmosphere with high reducing power such as a reducing atmosphere containing hydrogen and nitrogen, a fired product for obtaining a chlorosilicate phosphor that emits green light having high luminous efficiency is produced. The calcined product fired in an atmosphere having high reducing power has high luminous efficiency because the content ratio of ^{Eu 2+ contained in the calcined product increases.} Divalent Eu is likely to be oxidized to trivalent Eu, but by calcining the raw material mixture in a reducing atmosphere containing hydrogen and nitrogen and having high reducing power, Eu ³⁺ contained in the calcined product is reduced to Eu ^2+. .. ^{Therefore, the content ratio of Eu 2+} contained in the fired product is increased, and a fluorescent substance having high luminous efficiency can be produced.

Post-treatment after firing The fired product may be subjected to post-treatment such as pulverization, dispersion, solid-liquid separation, and drying. Solid-liquid separation can be performed by industrially commonly used methods such as filtration, suction filtration, pressure filtration, centrifugation and decantation. Drying can be performed by an industrially commonly used device such as a vacuum dryer, a hot air heating dryer, a conical dryer, and a rotary evaporator. If necessary, the fired product can be post-treated to produce a powdery fluorescent substance.

Adhesion of Oxide The obtained chlorosilicate phosphor is brought into contact with a solution containing a metal alkoxide containing at least one element selected from the group consisting of Al, Si, Zr and Ti as a phosphor core, and the metal alkoxide is prepared. Is hydrolyzed and alkoxide to attach an oxide containing at least one metal selected from the group consisting of Al, Si, Zr and Ti. It is preferable that at least one oxide selected from the group consisting of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO _{2 is attached to the phosphor core by the sol-gel method.} In the phosphor, at least one oxide selected from the group consisting of _{Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ adheres to a phosphor core composed of a chlorosilicate phosphor, preferably in the form of a film. ing. As a result, this film-like oxide functions as a protective film, deterioration of the phosphor due to the external environment can be suppressed, and the durability of the light emitting device using this phosphor can be improved.

The metal alkoxide is preferably a silane compound having two or more alkoxyl groups, and specifically, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, and the like. Propyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, titanium tetrapropoxide, titanium tetrabudoxide, aluminum triethoxyde, aluminum tripropoxide, aluminum tribdoxide, zirconium tetrapropoxide, zirconium tetrabutoxide Can be mentioned. The metal alkoxide is preferably tetraethoxysilane in consideration of workability and availability.

The solution containing the metal alkoxide preferably contains an organic solvent in consideration of workability.

The organic solvent contained in the solution containing the metal alkoxide is preferably a polar organic solvent, for example, ethyl acetate, tetrahydrofuran, N, N-diethylformamide, dimethyl sulfoxide, a linear or branched chain having 1 to 8 carbon atoms. Examples thereof include alcohols having an alkyl group, formic acid, carboxylic acids such as acetic acid, and ketones such as acetone. The polar organic solvent is preferably a lower alcohol or ketone having a linear or branched alkyl group having 1-3 carbon atoms. The polar organic solvent is more preferably ethanol or a ketone having a relative permittivity of 18 to 33, and more specifically, more preferably methanol (relative permittivity 33), ethanol (relative permittivity 24), 1-propanol. It is at least one selected from the group consisting of (relative permittivity 20), 2-propanol (relative permittivity 18), and acetone (relative permittivity 21). By including an acid or alkali catalyst in the solution containing the metal alkoxide, the decomposition rate of hydrolysis of the metal alkoxide can be accelerated. Examples of the acid or alkali solution serving as a catalyst include a hydrochloric acid solution and an ammonia solution.

_{A group consisting of Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ as main components by contacting a powdery chlorosilicate phosphor with a solution containing a metal alkoxide to hydrolyze and hydrolyze the metal alkoxide. At least one oxide selected from the above is adhered. For example, when the metal alkoxide is tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), the calcined product is brought into contact with a solution containing _{tetraethoxysilane (Si (OC 2} H ₅ ) _{4) to bring the tetraethoxysilane.} Orthosilicic acid (Si (OH) ₄ ) is formed by hydrolysis of orthosilicic acid (Si (OH) ₄ ), the dehydration reaction proceeds by the condensation polymerization of _{orthosilicic acid (Si (OH) 4), and silica (SiO 2} ) is the main component of the phosphor core. It adheres to the surface of the surface in the form of a film.

Light emitting device A light emitting device using a phosphor as a component of a wavelength conversion member will be described. The light emitting device according to the present disclosure includes a chlorosilicate phosphor and an excitation light source, and the light source has a emission peak wavelength in the range of 250 nm or more and 485 nm or less. The chlorosilicate phosphor preferably absorbs light from a light source and has an emission peak wavelength in the range of 495 nm or more and 548 nm or less.

An example of the light emitting device will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of a light emitting device.

The light emitting device 100 includes a molded body 40 having a recess, a light emitting element 10 as a light source, and a fluorescent member 50 that covers the light emitting element 10. The molded body 40 is formed by integrally molding a first lead 20 and a second lead 30 and a resin portion 42 containing a thermoplastic resin or a thermosetting resin. In the molded body 40, the first lead 20 and the second lead 30 forming the bottom surface of the recess are arranged, and the resin portion 42 forming the side surface of the recess is arranged. The light emitting element 10 is placed on the bottom surface of the concave portion of the molded body 40. The light emitting element 10 has a pair of positive and negative electrodes, and the pair of positive and negative electrodes are electrically connected to the first lead 20 and the second lead 30 via a wire 60, respectively. The light emitting element 10 is covered with a fluorescent member 50. The fluorescent member 50 includes a phosphor 70 that converts the wavelength of the light emitting element 10. The phosphor 70 may include a chlorosilicate phosphor as the first phosphor 71, and may include a second phosphor 72 and a third phosphor 73 having emission peak wavelengths having a wavelength range different from that of the first phosphor. The fluorescent member 50 functions not only as a wavelength conversion member but also as a member for protecting the light emitting element 10, the first fluorescent substance 71, the second fluorescent substance 72 and the third fluorescent substance 73 from the external environment. The light emitting device 100 receives power from the outside and emits light via the first lead 20 and the second lead 30.

The method for manufacturing the light emitting device is to prepare a molded body having a recess in which the first lead and the second lead and the resin portion are integrally molded, and the light emitting element is placed on the first lead. The pair of electrodes of the light emitting element are electrically connected to the first lead and the second lead, respectively, and the first phosphor and the second, if necessary, are connected by using a wire. It is preferable to include a resin composition containing a phosphor, a third phosphor, and a resin, which is placed in a recess of a molded body and cured to form a fluorescent member. The resin composition can be placed in the concave portion of the molded product by dropping (potting) using, for example, a discharge device (dispenser).

Light emitting element A light emitting element can be used as a light source. The light emitting element emits light in the wavelength range of 250 nm or more and 485 nm or less. In order to efficiently excite the phosphor, the light emitting device preferably has a emission peak wavelength in the range of 300 nm or more and 480 nm or less, and more preferably 350 nm or more and 480 nm or less. By using the light emitting element as an excitation light source, it is possible to construct a light emitting device that emits mixed color light having a desired color temperature or color tone of the light from the light emitting element and the fluorescence from the phosphor.

The half width of the emission peak in the emission spectrum of the emission element can be, for example, 30 nm or less. It is preferable to use a semiconductor light emitting device as the light emitting device. By using a semiconductor light emitting device as a light source, it is possible to obtain a stable light emitting device having high efficiency, high linearity of output with respect to input, and resistance to mechanical impact. As the semiconductor light emitting device, for example, a semiconductor light emitting device using a nitride-based semiconductor (In _X Al _Y Ga _1-XY N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) can be used. The half-value width of the phosphor and the half-value width of the light-emitting element mean the wavelength width of the light-emitting spectrum showing a light-emitting intensity of 50% of the maximum light-emitting intensity in the light-emitting spectrum.

Fluorescent member First fluorescent member The fluorescent member uses a chlorosilicate phosphor as the first fluorescent substance, and may contain a second fluorescent substance and a third fluorescent substance having different emission peak wavelength ranges from the first fluorescent substance. good. The first fluorophore consists of a fluorophore core made of chlorosilicate phosphor, which is durable even in a high temperature and high humidity environment, and Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TIO _{2 on the surface of the phosphor core.} It is preferable that the fluorophore has at least one oxide attached to it, which is selected from the above group.

The first phosphor can be contained in, for example, a fluorescent member covering a light source to form a light emitting device. In a light emitting device in which the light source is covered with a fluorescent member containing the first phosphor, a part of the light emitted from the light source is absorbed by the first phosphor, and the emission peak wavelength is set within the range of 495 nm or more and 548 nm or less. It is converted into green light and emitted. By using a light source that emits light in the wavelength range of 250 nm or more and 485 nm or less, a part of the emitted light can be more effectively used by the phosphor in the fluorescent member.

The amount of the first phosphor contained in the light emitting device can be appropriately selected according to the color finally desired. The content of the first phosphor may be 2 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the resin contained in the fluorescent member, and may be in the range of 10 parts by mass or more and 100 parts by mass or less. It is preferably in the range of 10 parts by mass or more and 50 parts by mass or less.

The fluorescent member may include a second fluorescent substance and a third fluorescent substance having different emission peak wavelength ranges from the first fluorescent substance. For example, the light emitting device has a desired color temperature by appropriately providing a light emitting element that emits blue light, a first phosphor excited by the light emitting element, and, if necessary, a second phosphor and a third phosphor. However, it is possible to emit mixed-color light having a wide color reproduction range or high color rendering properties.

Second Fluorescent As the second phosphor, for example, a yellow phosphor that absorbs light from a light source having a wavelength range of 250 nm or more and 485 nm or less and has an emission peak wavelength in the range of 530 nm or more and 580 nm or less can be used. .. The second phosphor, for _{example, (Ca, Sr, Ba)} 2 SiO 4: Eu, Si 6-w Al w O w N 8-w: Eu (0 <w ≦ 4.2), (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, (La, 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, (Sr, Ba, Ca) ₈ Examples _{thereof include a phosphor represented by MgSi 4} O ₁₆ (F, Cl, Br) ₂ : Eu (a chlorosilicate phosphor having a composition different from that of the first phosphor).
In the composition representing the phosphor, the plurality of elements separated by commas (,) in parentheses mean that at least one element among these plurality of elements is contained in the composition. .. The plurality of elements described separated by commas (,) in parentheses in the composition include at least one element selected from the plurality of elements separated by commas in the composition, and the plurality of elements. May contain a combination of two or more of the above. In the composition representing a phosphor, the element before the colon (:) represents the elements constituting the parent crystal and their molar ratios, and after the colon (:) represents the activating element.

The amount of the second phosphor contained in the light emitting device can be appropriately selected according to the color finally desired. The content of the second phosphor contained in the fluorescent member can be in the range of 1 part by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the resin contained in the fluorescent member, and is 1 part by mass or more and 100 parts by mass. It may be in the range of 2 parts by mass or less, and preferably in the range of 2 parts by mass or more and 50 parts by mass or less.

Third phosphor As the third phosphor, for example, a yellow phosphor that absorbs light from a light source in the wavelength range of 250 nm or more and 485 nm or less and has an emission peak wavelength in the range of 610 nm or more and 790 nm or less is used. Can be done. The third phosphor is, for example, 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.

The amount of the third phosphor contained in the light emitting device can be appropriately selected according to the color finally desired. The content of the third phosphor contained in the fluorescent member can be in the range of 1 part by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the resin contained in the fluorescent member, and is 1 part by mass or more and 100 parts by mass. It may be in the range of 2 parts by mass or less, and preferably in the range of 2 parts by mass or more and 50 parts by mass or less.

The total content of the phosphor in the fluorescent member can be, for example, in the range of 5 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the resin, and is in the range of 10 parts by mass or more and 250 parts by mass or less. It is more preferable, it is more preferably in the range of 15 parts by mass or more and 230 parts by mass or less, and further preferably it is in the range of 15 parts by mass or more and 200 parts by mass or less. When the total content of the phosphor in the fluorescent member is within the above range, the light emitted from the light emitting element can be efficiently wavelength-converted by the phosphor.

Examples of the resin constituting the fluorescent member include thermosetting resins such as silicone resin, epoxy resin, epoxy-modified silicone resin, and modified silicone resin.

The fluorescent member may further contain a filler, a light diffusing material, and the like in addition to the resin and the fluorescent substance. For example, by including a filler or a light diffusing material, the directivity from the light emitting element can be relaxed and the viewing angle can be increased. Examples of the filler and the light diffusing material include silica, titanium oxide, zinc oxide, zirconium oxide, and alumina. When the fluorescent member contains a filler or a light diffusing material, the content of the filler or the light diffusing material can be, for example, in the range of 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the resin.

Hereinafter, the present invention will be specifically described with reference to Examples. The present invention is not limited to these examples.

Example 1
CaCO ₃ , Eu ₂ O ₃ , MgO, SiO ₂ , and CaCl ₂ were used as raw materials. With these raw materials as the amount to be charged, the molar ratio of Si is 4, and the molar ratio of each element is Ca: Eu: Mg: Si: Cl = 7.75: 0.3: 1: 4: 2.5. Weighed and mixed to obtain a raw material mixture. The molar ratio of each element was calculated by revising the purity of each raw material to 100% by mass. Since Cl scatters during firing, it was blended in a larger amount than the target composition ratio (molar ratio). After the raw material mixture was filled in an alumina boat, it was calcined at 1170 ° C. for 12 hours in a hydrogen nitrogen atmosphere, which is a reducing atmosphere, and Ca _7.55 Eu _0.20 Mg _0.98 Si ₄ O _15.79 Cl ₁ A fired product having the composition represented by _{.91 was obtained.} Since the particles of the obtained calcined product are sintered with each other, they are pulverized with alumina beads, wet-dispersed, and then sieved to remove coarse particles and fine particles to obtain a chlorosilicate phosphor powder. rice field.

Examples 2 to 5 and Comparative Examples 1 to 3
Using the same raw materials as in Example 1, the amount of these raw materials charged is such that the molar ratio of Si is 4, and Ca, Eu, Mg, Si, and Cl have the charged molar ratios shown in Table 1 below. The powders of the chlorosilicate phosphors of each Example and Comparative Example were obtained in the same manner as in Example 1 except that they were weighed.

Comparative Example 4
Using the same raw materials as in Example 1, the amount of these raw materials charged is such that the molar ratio of Si is 4, and Ca, Eu, Mg, Si, and Cl are the charged molar ratios shown in Table 1 below. The powder of the chlorosilicate phosphor of Comparative Example 4 was obtained in the same manner as in Example 1 except that the powder was weighed.

Evaluation Emission characteristics The emission characteristics of the obtained phosphor were measured. The emission characteristics of the phosphors are as follows: using a spectral fluorometer (QE-2000 manufactured by Otsuka Electronics Co., Ltd.), each phosphor is irradiated with light having a wavelength of excitation light of 450 nm, and the temperature is room temperature (25 ° C ± 5 ° C). The emission spectrum in. FIG. 2 is a diagram showing emission spectra of the phosphor of Example 3 and the phosphor of Comparative Example 1. From the obtained emission spectrum, the emission peak wavelength λp (nm) and the internal quantum efficiency (%) were obtained. The internal quantum efficiency (%) was calculated by dividing the number of emitted photons (%) by the number of absorbed photons (%). The results are shown in Table 2 below.

Composition analysis The composition of the obtained chlorosilicate fluorophore was analyzed. For each element of Ca, Mg, Si, and Eu of the chlorosilicate phosphor, an inductively coupled plasma emission spectroscopic analyzer (ICP-AES: Inductively Coupled Plasma-Atomic Emission Spectrum) (manufactured by PerkinElmer, Optima 8300) was used. The molar ratio of the elements was measured. The molar ratio of the Cl element of the chlorosilicate phosphor was measured using a potentiometric titrator (AT-500N, manufactured by Kyoto Denshi Kogyo Co., Ltd.). In the composition of the phosphor, the molar ratio of each element other than Si was calculated based on the molar ratio 4 of Si. The results are shown in Table 2 below as "analytical molar ratios".

Particle size The obtained chlorosilicate phosphor has a particle size (volume median) at which the volume accumulation frequency from the small diameter side reaches 50% using a laser diffraction type particle size distribution measuring device (manufactured by MAVERN, product name: MASTER SIZER3000). Diameter) was measured. The results are shown in Table 2 below.

The phosphors of Examples 1 to 4 having an emission peak wavelength of 514 nm to 516 nm had higher internal quantum efficiency than the phosphors of Comparative Examples 1 and 2 having an emission peak wavelength of 514 nm to 515 nm. In the phosphors of Examples 1 to 4, the total of the variable x representing the molar ratio of Ca and the variable y representing the molar ratio of Eu is 7.70 or more and 7.95 or less (7.70 ≦ x + y ≦ 7.95). It is presumed that the internal quantum efficiency was increased as a result of the suppression of the formation of the double phase of calcium silicate. Further, in the phosphors of Examples 1 to 4, the variable b representing the molar ratio of Cl is in the range of more than 1.90 and 2.00 or less (1.90 <b ≦ 2.00), and is used as a mother crystal. It is presumed that the number of defects contained was small, and as a result, the internal quantum efficiency was high. As described above, the fluorescent substances of Examples 1 to 4 have higher conversion efficiency of light from the light source than the fluorescent substances of Comparative Examples 1 and 2.

The phosphor of Example 5 having an emission peak wavelength of 521 nm had a higher internal quantum efficiency than the phosphor of Comparative Example 3 having the same molar ratio of Eu and the emission peak wavelength. In the phosphor of Example 5, the total of the variable x representing the molar ratio of Ca and the variable y representing the molar ratio of Eu is in the range of 7.70 or more and 7.95 or less (7.70 ≦ x + y ≦ 7.95). It is presumed that the formation of multiple phases of calcium silicate was suppressed, and as a result, the internal quantum efficiency was increased. Further, the fluorescent substance of Example 5 has a variable b representing the molar ratio of Cl in the range of more than 1.90 and 2.00 or less (1.90 <b ≦ 2.00), and is included in the mother crystal. It is presumed that there are few defects and as a result, the internal quantum efficiency is high. As described above, the fluorescent substance of Example 5 has higher conversion efficiency of light from the light source than the fluorescent substance of Comparative Example 3.

The fluorescent substance of Comparative Example 4 emits light because the total of the variable x representing the molar ratio of Ca and the variable y representing the molar ratio of Eu exceeds 7.95 and the formation of a double phase of calcium silicate is not suppressed. It is presumed that the efficiency was considerably lower than that of Comparative Example 1.

As shown in FIG. 2, in the emission spectrum of the phosphor of Example 3, the emission intensity at the emission peak wavelength was higher than that of the phosphor of Comparative Example 1.

Measurement of Sr, Ba and Al The contents of Sr, Ba and Al in the obtained fluorescent substance of Example 3 were measured by using the same method as the above-mentioned composition analysis. The results are shown in Table 3 below.

Even when the phosphor of Example 3 contains Sr, Ba and Al, the total amount of these elements is 360 mass ppm or less, and the luminous efficiency is the phosphors of Comparative Examples 1 and 2. It became higher than. From this result, the chlorosilicate phosphor having a chemical composition represented by the formula (I) contains at least one element selected from Sr, Ba and Al, which are elements other than the elements constituting the composition. It was confirmed that the light emission efficiency did not decrease if the ratio was 360 mass ppm or less.

Example 6
Using the chlorosilicate phosphor of Example 3, the chlorosilicate phosphor was used as a phosphor core, and SiO ₂ was attached to the surface of the phosphor core as a main component in a film form. For 100 g of phosphor core, 180 ml of ethanol, 3.3 ml of an aqueous solution containing 3% by mass of ammonium chloride, 3.3 ml of an aqueous solution containing 3% by mass of calcium chloride, and ammonia water containing 18% by mass of ammonium. 30 ml of mixed mother liquor was prepared. The fluorescent core was placed in the mother liquor and stirred to disperse the fluorescent core in the mother liquor, and the temperature of the mother liquor was maintained at 45 ° C. to 55 ° C. A solution containing 23.2 g of tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ) in terms of silica is defined as solution A, 22.3 ml of ammonia water containing 18% by mass of ammonia, 22.3 ml of deionized water, and 3% by mass. Liquid B containing 1.5 ml of aqueous solution containing% ammonium chloride was prepared. While stirring the mother liquor, the solution A was added dropwise to the mother liquor at a rate of 5.6 ml / min and the solution B at a rate of 2.2 ml / min for a dropping time of 160 minutes to form a mixed solution. The mixture is stirred for 30 minutes, then the stirring is stopped, the phosphor having SiO ₂ adhered to the surface of the phosphor core is taken out from the mixture, dried at 100 ° C. for 15 hours, and then put on the surface of the phosphor core. A powder of the chlorosilicate phosphor of Example 6 to which SiO _{2 was attached was obtained.}

Comparative Example 5
Chlorosilicate of Comparative Example 5 in _{which SiO 2} adhered to the surface of the phosphor core in the same manner as in Example 6 except that the chlorosilicate phosphor of Comparative Example 1 was used and this fluorescent substance was used as the phosphor core. Fluorescent powder was obtained.

For the fluorescent substance of Example 6 and the fluorescent substance of Comparative Example 5, the particle size, the emission peak wavelength (λp (nm)), and the internal quantum efficiency (%) were measured by the same method as described above. The results are shown in Table 4.

The fluorescent substance of Example 6 had higher internal quantum efficiency than the fluorescent substance of Comparative Example 5. As shown in FIG. 3, the emission spectrum of the phosphor of Example 6 had a higher emission intensity than the emission spectrum of Comparative Example 5 in the wavelength range of 495 nm or more and 548 nm or less. _{From this result, even when SiO 2} is attached to the surface of the phosphor core of the chlorosilicate phosphor having the chemical composition represented by the formula (I), the luminous efficiency is higher than that of Comparative Example 5. It was maintained in a state. _{In the fluorescent substance of Example 6, the film-like SiO 2} is attached to the surface of the phosphor core of the chlorosilicate phosphor having the chemical composition represented by the formula (I), so that the film-like SiO ₂ is formed. As a protective film, deterioration is suppressed and durability is increased.

Light emitting device Example 7
A light emitting device according to the embodiment shown in FIG. 1 was manufactured. As a first phosphor, using the chlorosilicate phosphors of Examples 6, _Y 3 _Al 5 _O 12 as the second phosphor: using Ce, as a third phosphor (Sr, Ca) AlSiN _3: with Eu, As the light emitting element, a nitride semiconductor light emitting element having a emission peak wavelength of 456 nm was used. The blending amount of each fluorescent substance is adjusted so that the light from the light emitting element, the first fluorescent substance, the second fluorescent substance, and the third fluorescent substance has a correlated color temperature of 5000 K, and the first fluorescent substance and the first fluorescent substance are used. A resin composition containing a second fluorescent substance, a third fluorescent substance, and a silicone resin was prepared, and the resin composition was placed by dropping (potting) the resin composition into the concave portion of the molded body using a dispenser. A light emitting device provided with a fluorescent member obtained by curing the resin composition was produced.

Comparative Example 6
A light emitting device was produced in the same manner as in Example 7 except that the chlorosilicate phosphor of Comparative Example 5 was used as the first fluorescent substance.

The luminous flux was measured for the light emitting devices of Example 7 and Comparative Example 6 using the total luminous flux measuring device using the relative luminous flux integrating sphere. The relative luminous flux of the light emitting device of Example 7 was calculated with the light flux of the light emitting device of Comparative Example 6 as 100%. The results are shown in Table 5.

In the light emitting device of Example 7, the relative luminous flux at the correlated color temperature of 5000 K was higher than that of the light emitting device of Comparative Example 6.

Example 8
Fluorescence in the same manner as in Example 6 except that the chlorosilicate phosphor of Example 3 was used as the phosphor core and tetraethoxysilane (Si (OC ₂ H ₅ ) _{4) was changed to 6.8 g in terms of silica.} The powder of the chlorosilicate fluorescent substance of Example 8 in _{which SiO 2} was attached to the surface of the body core was obtained.

For the chlorosilicate phosphor of Example 8 and the chlorosilicate phosphor of Example 6, the particle size, the emission peak wavelength (λp (nm)), and the internal quantum efficiency (%) were measured by the same method as described above. The results are shown in Table 6.

The chlorosilicate phosphor of Example 8 having SiO ₂ adhered to the surface had almost the same emission peak wavelength and internal quantum efficiency as the chlorosilicate phosphor of Example 6. On the other hand, the chlorosilicate phosphor of Example 8 had a smaller volume median diameter than the chlorosilicate phosphor of Example 6.

Light emitting device Example 9
A light emitting device was produced in the same manner as in Example 7 except that the chlorosilicate phosphor of Example 8 was used as the first phosphor.

The luminous flux was measured for the light emitting device of Example 9 using the total luminous flux measuring device using the relative luminous flux integrating sphere. The relative luminous flux of the light emitting device of Example 9 was calculated with the light flux of the light emitting device of Comparative Example 6 as 100%. The results are shown in Table 7 together with the results of the light emitting device of Example 7.

The light emitting device of Example 9 had a higher relative luminous flux at a correlated color temperature of 5000 K than that of the light emitting device of Example 7. The chlorosilicate phosphor of Example 8 used in the light emitting device of Example 9 has a smaller particle size than the chlorosilicate phosphor of Example 6 used in the light emitting device of Example 7, and therefore has a potted resin composition. It is presumed that the light is unevenly distributed on the upper side of the object, that is, on the light emitting side in the fluorescent member. When the chlorosilicate phosphor is unevenly distributed on the light emitting side in the fluorescent member of the light emitting device, the light wavelength-converted by the chlorosilicate phosphor is absorbed by the second phosphor and the third phosphor. It was speculated that it would be difficult to do. Therefore, the relative luminous flux of the light emitting device of Example 9 was higher than that of the emitting device of Example 7.

The chlorosilicate fluorophore of the present disclosure can be used in a light emitting device. The light emitting device of the present disclosure can be suitably used as a light source for lighting. In particular, it can be suitably used for an illumination light source using a light emitting diode as an excitation light source, an LED display, a liquid crystal backlight light source, a signal device, an illumination type switch, various sensors, various indicators, a small strobe, and the like.

10: light emitting device, 20: first lead, 30: second lead, 40: molded body, 50: fluorescent member, 60 wires, 70: fluorescent material, 71: first fluorescent material, 72: second fluorescent material , 73, Third Fluorescent Agent, 100: Light Emitting Device.

Claims (10)

A chlorosilicate fluorescent substance having a chemical composition represented by the following formula (I).
Ca _x Eu _y Mg _z Si ₄ O _a Cl _b (I)
(In the formula (I), a, b, x, y and z are 7.0 ≦ x ≦ 7.94, 0.01 ≦ y ≦ 1.0, 7.70 ≦ x + y ≦ 7.95, respectively. It is a number that satisfies 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, and 1.90 <b ≦ 2.00.) In the formula (I), x, y, a and b satisfy 7.80 ≦ x + y ≦ 7.95 and 15.73 ≦ a ≦ 16.05, 1.95 ≦ b <2.00, respectively. The chlorosilicate phosphor according to claim 1. The chlorosilicate fluorophore according to claim 1 or 2 , further comprising Al. Sr, includes at least one element selected from the group consisting of Ba and Al, Sr, the total phosphor 100 wt% of Ba and Al, is 360 mass ppm or less, according to claim 1 or et 3 The chlorosilicate phosphor according to any one of the above items. A phosphor core is an oxide having a chemical composition, on the surface of the phosphor _core, at least one oxide is deposited is selected from the group consisting of _{Al 2 O 3, SiO 2,} ZrO 2 and TiO ₂ It has been, chlorosilicate phosphor according to any one of claims 1 or al 4. A light source having an emission peak wavelength within 485nm the range above 250 nm, the light emitting device including a chlorosilicate phosphor according to any one of claims 1, 4, and 5. A group consisting of a compound containing Eu, a compound containing Eu, a compound containing Mg, a compound containing Si, and a compound containing Cl, and a compound containing Eu, a compound containing Mg, and a compound containing Si. At least one compound selected from the above is an oxide, and the compound containing Cl may contain Ca or Mg.
When the mole ratio of Si in the compound containing Si is 4 mol, the molar ratio of Ca is in the range of 7 or more and 8.2 or less, the molar ratio of Eu is in the range of 0.01 or more and 1.1 or less, and the mole of Mg is used. The ratio is in the range of 0.9 or more and 1.1 or less, the total of Ca and Eu is in the range of 8.05 or more and 8.25 or less, and the molar ratio of Cl is in the range of 2.0 or more and 3.0 or less. Weigh each compound so that it is inside and mix it to obtain a raw material mixture.
Baking the raw material mixture and
A method for producing a fluorescent substance, which comprises obtaining a chlorosilicate fluorescent substance having a chemical composition represented by the following formula (I).
Ca _x Eu _y Mg _z Si ₄ O _a Cl _b (I)
(In the formula (I), a, b, x, y and z are 7.0 ≦ x ≦ 7.94, 0.01 ≦ y ≦ 1.0, 7.70 ≦ x + y ≦ 7.95, respectively. It is a number that satisfies 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, and 1.90 <b ≦ 2.00.) The method for producing a fluorescent substance according to claim 7, wherein the firing temperature is in the range of 1000 ° C. or higher and 1300 ° C. or lower. The method for producing a fluorescent substance according to claim 7 or 8 , wherein the firing atmosphere is a reducing atmosphere. The chlorosilicate phosphor is used as a phosphor core, and the fluorosilicate core comprises attaching at least one oxide selected from the group consisting of _{Al 2} O ₃ , SiO ₂ , ZrO ₂ and TiO _{2 to the phosphor core.} The method for producing a fluorescent substance according to any one of claims 7 to 9.

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