JP2020076078A - Chlorosilicate phosphor, manufacturing method thereof, and light-emitting device - Google Patents

Abstract

To provide a chlorosilicate phosphor having high luminous efficiency; and to provide a manufacturing method thereof, and a light-emitting device.SOLUTION: A chlorosilicate phosphor has a chemical composition containing Ca, Eu, Mg, Si, O and Cl, and assuming that a mole ratio of Si in the 1 mol chemical composition is 4, contains Ca in the range of 7.0 or more and 7.94 or less, in terms of the mole ratio, Eu in the range of 0.01 or more and 1.0 or less, in terms of the mole ratio, the total of Ca and Eu in the range of 7.70 or more and 7.95 or less, in terms of the mole ratio, Mg in the range of 0.9 or more and 1.1 or less, in terms of the mole ratio, and Cl in the range of 2.00 or less and over 1.90, in terms of the mole ratio.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a chlorosilicate phosphor, a method for manufacturing the same, and a light emitting device.

  By combining a light source and a wavelength conversion member that is excited by light from this light source and can emit light of a hue different from that of the light source, it is possible to emit light of various hues according to the principle of light color mixing. Light emitting devices have been developed. For example, a light emitting device in which a light emitting element such as a light emitting diode (hereinafter, referred to as “LED”) and a phosphor that is a wavelength conversion member are combined corresponds to visible light from ultraviolet light emitted from the light emitting element. When the phosphors that emit red, green, and blue light are excited by light on the short wavelength side, the three primary colors of light, red, green, and blue, are mixed, and white light is obtained.

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

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

Among the silicate phosphor, as a typical phosphor that emits green light, for example, Eu-activated calcium magnesium chlorosilicate (commonly composition formula _{Ca 8 Mg (SiO 4) 4} Cl 2: Table with Eu (Hereinafter referred to as "chlorosilicate phosphor"). The green phosphor has a great influence on the luminous flux of the light emitting device and further enhances the luminous flux of the light emitting device. Therefore, a chlorosilicate phosphor having higher luminous efficiency is required.
Then, it aims at providing the fluorescent substance which has high luminous efficiency, its manufacturing method, and a light-emitting device.

The present invention includes the following aspects.
A 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 mole of the chemical composition is 4, Ca is molar. In the range of 7.0 or more and 7.94 or less, the molar ratio of Eu in the range of 0.01 or more and 1.0 or less, and the total of Ca and Eu in the molar ratio of 7.70 or more and 7.95 or less. Among them, the chlorosilicate phosphor contains 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 an emission peak wavelength within a range of 250 nm to 485 nm and the chlorosilicate phosphor.

A third aspect of the present invention is to prepare a compound containing Ca, a compound containing Eu, a compound containing Mg, a compound containing Si, and a compound containing Cl, and containing a compound containing Eu and Mg. At least one compound selected from the group consisting of a compound and a compound containing Si is an oxide, and the compound containing Cl may contain Ca or Mg,
When Si in the compound containing Si is 4 mol, the molar ratio of Ca is 7 or more and 8.2 or less, the molar ratio of Eu is 0.01 or more and 1.1 or less, and the molar ratio of Mg is The ratio is 0.9 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 Cl molar ratio is 2.0 or more and 3.0 or less. Each of the compounds is weighed and mixed so as to obtain a raw material mixture, the raw material mixture is fired, and a chlorosilicate phosphor is obtained.

  According to the above-mentioned aspect, it is possible to provide a chlorosilicate phosphor having high luminous efficiency, a method for producing the same, and a light emitting device.

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

  Hereinafter, a chlorosilicate phosphor, a method for manufacturing the same, and a light emitting device according to the present disclosure will be described based on embodiments. However, the embodiments described 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. Note that 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.

Phosphor The phosphor has a chemical composition containing Ca, Eu, Mg, Si, O, and Cl. When the molar ratio of Si in 1 mole 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, the molar ratio of Eu to 0.01 or more and 1.0 or less, and the sum of Ca and Eu in the molar ratio of 7.70 to 7.95, Mg Is a chlorosilicate phosphor containing Cl in a range of 0.9 or more and 1.1 or less and Cl in a range of more than 1.90 and 2.00 or less.

The phosphor is preferably a chlorosilicate phosphor 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. (Numbers satisfying 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, 1.90 <b ≦ 2.00.)

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

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 activator element and is replaced with a part of Ca site in a host crystal that constitutes the phosphor. it is conceivable that. In the composition of the chlorosilicate phosphor, the total molar ratio of Ca and Eu is preferably a value 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 supposed to be. However, the present inventors have found that when the total molar ratio of Ca and Eu in the chlorosilicate phosphor is 8 or a numerical value exceeding 8 which is the molar ratio of Ca in 1 mol of the theoretical composition, Ca is bonded to the silicate. It has been found that the multiple phases of calcium silicate are likely to be generated, and the luminous efficiency is rather decreased. In the chlorosilicate phosphor, the maximum value of the total of Ca and Eu in the chemical composition of 1 mol is a molar ratio, and is 7.95 or less, which is smaller than 8 which is the molar ratio of Ca in the theoretical composition of 1 mol of chlorosilicate. Generation of multiple phases of calcium silicate is suppressed, and luminous efficiency can be increased. The chlorosilicate phosphor has a total molar ratio of Ca and Eu of 7.70 or more and 7.95 or less, when the molar ratio of Si in 1 mol of the chemical composition is 4. It is preferably contained within the range of 7.80 to 7.95. In the chlorosilicate phosphor having the chemical composition represented by the formula (I), the sum 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), and preferably 7.80 or more and 7.95 or less (7.80 ≦ x + y ≦ 7.95). When the total of Ca and Eu in the chemical composition of 1 mol is 7.70 or more in molar ratio, the chlorosilicate phosphor can maintain a stable crystal structure and can increase the luminous efficiency.

  The chlorosilicate phosphor contains Cl constituting the host crystal in a molar ratio range of more than 1.90 and 2.00 or less. If the molar ratio of Cl in the theoretical composition of chlorosilicate is less than 1.90, defects may occur in the host crystal, and the luminous efficiency may decrease. When the chlorosilicate phosphor contains Cl constituting the host crystal in a molar ratio of more than 2.00, defects may occur in the host crystal, and the luminous efficiency may decrease. Due to the stability of the crystal structure, the chlorosilicate phosphor contains Cl constituting the host crystal in a molar ratio of more than 1.90 and not more than 2.00, preferably not less than 1.95 and not more than 2.00. 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 host crystal is more than 1.90 and not more than 2.00 (1.90 <b ≦ 2.00), preferably 1.95 or more and less than 2.00 (1.95 ≦ b <2.00).

  The chlorosilicate phosphor contains Ca in a chemical composition of 1 mol in a molar ratio of 7.00 to 7.94 inclusive, and preferably in a range of 7.20 to 7.90 inclusive, in order to increase the luminous efficiency. , More preferably 7.30 or more and 7.80 or less, and even more preferably 7.40 or more and 7.70 or less. In the phosphor having the chemical composition represented by the formula (I), the variable x representing the molar ratio of Ca is in the range of 7.00 or more and 7.94 or less (7.00 ≦ x ≦ 7.94), It is preferably within the range of 7.20 to 7.90 (7.20 ≦ x ≦ 7.90), and more preferably 7.30 to 7.80 (7.30 ≦ x ≦ 7.80). It is within the range, and more preferably 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 or less. It is contained in the range of not less than 0.80 and more preferably in the range of not less than 0.15 and not more than 0.60. As long as the chlorosilicate phosphor contains Eu, which is an activator, in a molar ratio of 0.01 or more and 1.00 or less, the chlorosilicate phosphor absorbs light from a light source and emits electrons of Eu. Are excited, and the wavelength of the light of the light source can be converted by the excitation energy. As long as the chlorosilicate phosphor contains Eu in a molar ratio of 0.01 to 1.00, it absorbs light from a light source having an emission peak wavelength in the range of 250 to 485 nm. Thus, light having an emission peak wavelength in the range of 495 nm to 548 nm can be emitted. If the chlorosilicate phosphor contains Eu in a molar ratio of 0.01 or more and 1.00 or less, the luminous efficiency can be increased without lowering the luminous efficiency due to concentration quenching or the like. .. In the chlorosilicate phosphor having the chemical composition represented by the formula (I), the variable y representing the molar ratio of Eu is in the range of 0.01 or more and 1.00 or less (0.01 ≦ y ≦ 1.00). And 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. 80), and more preferably 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 chemical composition of 1 mol in a molar ratio of 0.90 or more and 1.10 or less, preferably 0.95 or more and 1.05 or less. Including 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 ≦ 1.10), preferably 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 chemical composition of 1 mol in a molar ratio of 15.60 or more and 16.10 or less, preferably 15.73 or more and 16.05 or less. Within the range, more preferably within the range from 15.78 to 16.00. 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). ≦ a ≦ 16.10), preferably 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 following range (15.78 ≦ a ≦ 16.00). In the chemical composition represented by the formula (I), the variable a representing the molar ratio of O is defined by 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 attached to the surface of the phosphor core. Is preferred.
Since the chlorosilicate phosphor contains chlorine in its composition, it tends to deteriorate in a high temperature and high humidity environment. The phosphor has a high temperature when 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 surface of the phosphor core made of a chlorosilicate phosphor. In a high-humidity environment, surface deterioration can be suppressed and the durability of a light-emitting device using a chlorosilicate phosphor can be improved.

Examples of 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 on} the surface of a phosphor core made of a chlorosilicate phosphor include Al and Si. , A Zr and Ti, and a sol-gel method using a solution containing a metal alkoxide containing at least one metal element selected from the group consisting of Zr and Ti. The oxide attached to the surface of the phosphor core is preferably attached in a film form on the surface of the phosphor core in order to suppress deterioration of the phosphor core, and is formed in a film form on the entire surface of the phosphor core. It is more preferable that they are attached.

  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 the metal contained in the oxide, and 3 parts by mass. It is more preferably in the range of not less than 25 parts by mass and more preferably in the range of not less than 4 parts by mass and not more than 24 parts by mass. 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 the metal contained in the oxide, and may be 3 parts by mass. It may be in the range of not less than 10 parts by mass and not more than 10 parts by mass. 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 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 the metal contained in the oxide, Oxide can be attached in the form of a film on the surface, suppressing the deterioration of the surface of the chlorosilicate phosphor even under high temperature and high humidity environment, and improving the durability of the light emitting device using the chlorosilicate phosphor be able to. A relatively thin film if the oxide attached to the surface of the phosphor core is 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 the metal contained in the oxide. -Like oxide 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 having the oxide attached to the surface of the phosphor core, the chlorosilicate phosphor can be unevenly distributed on the light emission side in the fluorescent member. Thereby, the light whose wavelength is converted by the chlorosilicate phosphor is easily extracted 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, further preferably 5.0 μm or more, preferably 30.0 μm or less, more preferably 25. It is 0 μm or less. If 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 the light from the light source becomes higher, and the emission efficiency of the light emitting device using the chlorosilicate phosphor becomes higher. can do. Further, if the particle size of the chlorosilicate phosphor is 30.0 μm or less, workability in the manufacturing process of the light emitting device can be improved. The particle size of the chlorosilicate phosphor is a particle size (hereinafter, also referred to as “volume median size”) where the volume cumulative frequency from the small diameter side reaches 50% as measured by a laser diffraction type particle size distribution measuring device. is there. As the laser diffraction type particle size distribution measuring device, for example, MASTER SIZER 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 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 homologous elements to Ca constituting the composition of the chlorosilicate phosphor, are contained in the compound containing Ca which is a raw material of the chlorosilicate phosphor, and may be mixed in the phosphor. In addition, Al may be contained in a compound containing Si, which is a raw material of the chlorosilicate phosphor, and may be used as a material of a dispersion medium used in the production of the phosphor. May be mixed during manufacturing. Even if the chlorosilicate phosphor contains at least one element selected from Sr, Ba and Al, which is an element other than the elements constituting the composition, as long as it has a ratio of 360 mass ppm or less. The luminous efficiency does not decrease. When two or more elements selected from the group consisting of Sr, Ba and Al are contained in the chlorosilicate phosphor, 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 mass ppm or less with respect to 100 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, may be 300 mass ppm or less, and may be 250 mass. It may be ppm or less.

Method for producing phosphor A method for producing a phosphor comprises preparing a compound containing Ca, a compound containing Eu, a compound containing Mg, a compound containing Si, and a compound containing Cl, 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. When it 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 molar ratio of Mg is 0.1. It is in the range of 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 2.0 or more and 3.0 or less. Each of the compounds is weighed and mixed so as to fall within each of these ranges to obtain a raw material mixture, firing the raw material mixture, and obtaining a phosphor.

As each compound Ca-containing compound, Eu-containing compound, and Mg-containing compound, a halogen salt, oxide, carbonate, phosphate, silicate, or ammonium salt containing each element can be used. As the compound containing Si, an oxide containing Si, a hydroxide, an oxynitride compound, a nitride compound, an imide compound, or an amide compound can be used. The Cl-containing compound may be a chloride containing Ca or Mg. Specifically, examples of the compound containing Ca include CaF ₂ , CaCl ₂ , and CaCO ₃ . Examples of the compound containing Eu include metal europium, Eu ₂ O ₃ , EuN, an imide compound containing 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 of 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 is The compound containing Ca and the compound containing Eu are weighed so that the molar ratio is within the range of 8.05 to 8.25. The Ca-containing compound and the Eu-containing compound are weighed so that the molar ratio is within the above range, and the total molar ratio of Ca and Eu in the obtained phosphor is the molar ratio in the theoretical composition of chlorosilicate. It can be set to a value close to a certain value of 8 and a molar ratio not exceeding 8. By adjusting the total molar ratio of Ca and Eu in the phosphor thus obtained, Ca does not combine with silicate to form a double phase of calcium silicate, and thus a phosphor having high luminous efficiency is manufactured. be able to. In the compound containing Ca, when Si is 4 mol, the molar ratio of Ca is preferably in the range of 7.2 or more and 8.1 or less, more preferably in the range of 7.4 or more and 8.0 or less. And more preferably 7.5 to 7.9 inclusive. 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, more preferably 0.10 or more and 0.9 or less. Is more preferably in the range of 0.12 or more and 0.8 or less. 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. To do.

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

  In the compound containing Cl, when Si is 4 mol, the molar ratio of Cl is in the range of 2.0 or more and 3.0 or less, preferably in the range of 2.1 or more and 2.8 or less, More preferably, it is weighed so that it falls within the range of 2.2 or more and 2.7 or less. When the molar ratio of Cl in the chemical composition of 1 mol contained in the obtained phosphor is as low as 1.90 or less, a defect may occur in the host crystal of the obtained phosphor, which easily scatters when the raw material is heat-treated, It is preferable that a compound containing Cl is included so that the molar ratio becomes 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 elements are weighed so that the molar ratio of each element constituting the chemical composition of the phosphor falls within the above-mentioned molar ratio range. Preferably.

Raw Material Mixture The weighed compounds are wet or dry mixed using a mixer to obtain a raw material mixture. As the mixer, a crusher such as a vibration mill, a roll mill or a jet mill can be used as well as a ball mill which is commonly used in industry. By pulverizing the raw material, the specific surface area can be increased. Further, the raw material, in order to keep the specific surface area of the particles within a certain range, a settling tank that is usually used industrially, a hydrocyclone, a wet separator such as a centrifugal separator, a cyclone, a dry classifier such as an air separator. It can also be used for classification.

Flux The raw material mixture may include a flux. Since the raw material mixture contains the flux, the reaction between the raw materials is further promoted, and further, the solid-phase reaction proceeds more uniformly, so that a fired product to be used for obtaining a phosphor having better emission characteristics is produced. be able to. For example, when the heat treatment for obtaining the fired product is in the temperature range of 1000 ° C. or more and 1250 ° C. or less, and when the temperature of this range uses a halide or the like as the flux, it is almost the same as the liquid crystal formation temperature 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, and the like can be used. The flux can be adjusted so that the composition ratio of the cations contained in the flux is the composition of the fired product desired, and flack can be added as a part of the raw material of the phosphor, or the composition of the fired product desired. As described above, after adding the respective raw materials, the flux can be added in the form of further addition.

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

Firing The raw material mixture is placed in a crucible or boat of SiC, quartz, alumina, BN or the like and fired in a furnace. By firing the raw material mixture, a powder of the fired 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 in 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. Regarding the firing, the secondary firing may be performed after the primary firing, or the firing may be performed a plurality of times.

  The firing time for one time is preferably 1 hour or more and 30 hours or less. It is also possible to change the temperature stepwise during the single firing. For example, two-step firing (multi-step firing) in which the first-step firing is performed in the range of 800 ° C. or higher and 1000 ° C. or lower, and the second stage firing is performed by gradually raising the temperature in the range of 1000 ° C. or higher and 1300 ° C. May be performed.

  The firing of the raw material mixture is preferably performed in a nitrogen atmosphere having a reducing property. The firing atmosphere is more preferably a nitrogen atmosphere containing a reducing hydrogen gas. The firing atmosphere may be a reducing atmosphere using solid carbon in the air atmosphere.

By firing in an atmosphere having 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 emission efficiency is manufactured. The fired product fired in an atmosphere having a high reducing power has high luminous efficiency because the content ratio of Eu ²⁺ contained in the fired product increases. Although divalent Eu is easily oxidized into trivalent Eu, Eu ³⁺ contained in the calcined product is reduced to Eu ²⁺ by calcining the raw material mixture in a reducing atmosphere containing hydrogen and nitrogen and having high reducing power. .. Therefore, the content ratio of Eu ²⁺ contained in the fired product is increased, and a phosphor having high luminous efficiency can be manufactured.

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 carried out by a method commonly used in industry such as filtration, suction filtration, pressure filtration, centrifugation, decantation and the like. Drying can be carried out by an apparatus usually used in industry such as a vacuum dryer, a hot-air heating dryer, a conical dryer, and a rotary evaporator. If necessary, the fired product may be subjected to post-treatment to produce a powdered phosphor.

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 to form a metal alkoxide. Is hydrolyzed and polycondensed to deposit an oxide containing at least one metal selected from the group consisting of Al, Si, Zr and Ti. At least one oxide selected from the group consisting of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ is preferably attached to the phosphor core by the sol-gel method. The phosphor is formed by adhering at least one oxide selected from the group consisting of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ to a phosphor core made of a chlorosilicate phosphor, preferably in the form of a film. ing. As a result, this film-shaped oxide functions as a protective film, and it is possible to suppress the deterioration of the phosphor due to the external environment, and it is possible to improve the durability of the light emitting device using this phosphor.

  The metal alkoxide is preferably a silane compound having two or more alkoxy groups, specifically, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, Propyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, titanium tetrapropoxide, titanium tetrabutoxide, aluminum triethoxide, aluminum tripropoxide, aluminum tributoxide, zirconium tetrapropoxide, zirconium tetrabutoxide. Is 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, and examples thereof include ethyl acetate, tetrahydrofuran, N, N-diethylformamide, dimethyl sulfoxide, and a straight chain or branched chain having 1 to 8 carbon atoms. Examples thereof include alcohols having an alkyl group, carboxylic acids such as formic acid and 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 to 3 carbon atoms. The polar organic solvent is more preferably ethanol or ketone having a relative dielectric constant of 18 to 33, and specifically, more preferably methanol (relative dielectric constant 33), ethanol (relative dielectric constant 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 the acid or alkali catalyst in the solution containing the metal alkoxide, the decomposition rate of the hydrolysis of the metal alkoxide can be accelerated. Examples of the acid or alkali solution serving as a catalyst include hydrochloric acid solution and ammonia solution.

A group consisting of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ as main components by bringing a powdery chlorosilicate phosphor into contact with a solution containing a metal alkoxide to hydrolyze and polycondense the metal alkoxide. At least one oxide selected from is deposited. For example, when the metal alkoxide is tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ), the fired product is brought into contact with a solution containing tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ) to give tetraethoxysilane. by hydrolyzing, orthosilicate (Si _{(OH) 4)} is formed, the process proceeds dehydration reaction by polycondensation of ortho silicic acid (Si _{(OH) 4),} silica as a main component (SiO ₂₎ is phosphor core Is attached to the surface of the as a film.

Light-Emitting Device A light-emitting device that uses a phosphor as a component of a wavelength conversion member will be described. A light emitting device according to the present disclosure includes a chlorosilicate phosphor and an excitation light source, and the light source has an emission peak wavelength within a 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 sectional view showing an example of a light emitting device.

  The light emitting device 100 includes a molded body 40 having a concave portion, a light emitting element 10 serving as a light source, and a fluorescent member 50 covering the light emitting element 10. The molded body 40 is formed by integrally molding the first lead 20 and the second lead 30, and a resin portion 42 containing a thermoplastic resin or a thermosetting resin. The molded body 40 has the first lead 20 and the second lead 30 forming the bottom surface of the recess, and the resin portion 42 forming the side surface of the recess. The light emitting element 10 is mounted on the bottom surface of the recess 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 wires 60, respectively. The light emitting element 10 is covered with a fluorescent member 50. The fluorescent member 50 includes a fluorescent material 70 that converts the wavelength of the light emitting element 10. The phosphor 70 includes a chlorosilicate phosphor as the first phosphor 71, and may include a second phosphor 72 and a third phosphor 73 having emission peak wavelengths different in wavelength range from 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 body 71, the second fluorescent body 72, and the third fluorescent body 73 from the external environment. The light emitting device 100 receives electric power from the outside via the first lead 20 and the second lead 30 to emit light.

  A method of manufacturing a light emitting device includes preparing a molded body having a concave portion, which is obtained by integrally molding a first lead and a second lead, and a resin portion, and forming a light emitting element on the first lead. Is placed and electrically connected to the pair of electrodes of the light emitting element, the first lead and the second lead, respectively, using a wire, the first phosphor, and the second phosphor if necessary. It is preferable that a resin composition containing a phosphor, a third phosphor, and a resin 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 body by dropping (potting) using, for example, a discharging device (dispenser).

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

The full width at half maximum of the emission peak in the emission spectrum of the light emitting element can be, for example, 30 nm or less. A semiconductor light emitting element is preferably used as the light emitting element. By using the semiconductor light emitting element as the light source, it is possible to obtain a stable light emitting device having high efficiency, high linearity of output with respect to input, and strong against mechanical shock. As the semiconductor light-emitting device can be used, for example, a semiconductor light emitting device using nitride semiconductor _{(In X Al Y Ga 1-} X-Y N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1). The full width at half maximum of the phosphor and the full width at half maximum of the light emitting element mean the wavelength width of the emission spectrum showing the emission intensity of 50% of the maximum emission intensity in the emission spectrum.

Fluorescent Member First Phosphor The fluorescent member has a chlorosilicate phosphor as the first phosphor, and may include a second phosphor and a third phosphor each having a different emission peak wavelength range from the first phosphor. Good. The first phosphor is a phosphor core made of a chlorosilicate phosphor that has durability even in a high temperature and high humidity environment, and Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO ₂ are formed on the surface of the phosphor core. It is preferable that the phosphor has at least one oxide selected from the group consisting of:

  The first phosphor can be included in, for example, a fluorescent member that covers the light source to form a light emitting device. In the light emitting device in which the light source is covered with the fluorescent member containing the first fluorescent substance, a part of the light emitted from the light source is absorbed by the first fluorescent substance, and the emission peak wavelength falls within the range of 495 nm to 548 nm. 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 to be finally obtained. 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 within the range of 10 parts by mass or more and 50 parts by mass or less.

  The fluorescent member may include a second fluorescent material and a third fluorescent material each having a different emission peak wavelength range from the first fluorescent material. For example, a light emitting device has a desired color temperature by appropriately including a light emitting element that emits blue light, a first phosphor that is excited by the light emitting element, and a second phosphor and a third phosphor as necessary. However, mixed color light having a wide color reproduction range or high color rendering properties can be emitted.

Second Phosphor As the second phosphor, for example, a yellow phosphor that absorbs light from a light source in a wavelength range of 250 nm to 485 nm and has an emission peak wavelength in a range of 530 nm to 580 nm can be used. .. The second phosphor is, 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 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) can be used.
In the composition representing the phosphor, a plurality of elements described by being separated by commas (,) in parentheses means that at least one element of these plurality of elements is contained in the composition. .. A plurality of elements described by being separated by commas (,) in parentheses in the composition include at least one element selected from a plurality of elements separated by commas in the composition, and From these, two or more kinds may be included in combination. In the composition representing the phosphor, the colon (:) is in front of the elements constituting the host crystal and their molar ratio, and the colon (:) is in the activator element.

  The amount of the second phosphor contained in the light emitting device can be appropriately selected according to the color to be finally obtained. The content of the second phosphor contained in the fluorescent member may 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 1 part by mass or more and 100 parts by mass or more. The amount may be within the range of 2 parts by mass or less and is preferably within 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 to 485 nm and has an emission peak wavelength in the range of 610 nm to 790 nm is used. You can 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 to be finally obtained. The content of the third phosphor contained in the fluorescent member may 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 1 part by mass or more and 100 parts by mass or more. The amount may be within the range of 2 parts by mass or less and is preferably within 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 preferable that it is in the range of 15 parts by mass or more and 230 parts by mass or less, and further preferably 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 wavelength of light emitted from the light emitting element can be efficiently converted by the phosphor.

  Examples of the resin that constitutes 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 include a filler, a light diffusing material, and the like, in addition to the resin and the fluorescent material. For example, by including the filler or the 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 diffusion material include silica, titanium oxide, zinc oxide, zirconium oxide, alumina and the like. 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 invention is not limited to these examples.

Example 1
CaCO ₃ , Eu ₂ O ₃ , MgO, SiO ₂ , and CaCl ₂ were used as each raw material. These raw materials are 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. Then, they were weighed and mixed to obtain a raw material mixture. The molar ratio of each element was calculated by modifying the purity of each raw material to 100% by mass. Since Cl scatters at the time of firing, Cl is added in a larger amount than the intended composition ratio (molar ratio). After filling the raw material mixture into an alumina boat, firing was performed at 1170 ° C. for 12 hours in a hydrogen-nitrogen atmosphere that is a reducing atmosphere, and Ca _7.55 Eu _0.20 Mg _0.98 Si ₄ O _15.79 Cl ₁ A calcined product having a composition represented by _.91 was obtained. Since the particles in the obtained fired product are sintered, the particles are pulverized with alumina beads, wet-dispersed, and then sieved to remove coarse particles and fine particles to obtain a powder of chlorosilicate phosphor. It was

Examples 2 to 5 and Comparative Examples 1 to 3
Using the same raw materials as in Example 1, the feed amounts of these raw materials were set such that the molar ratio of Si was 4, and Ca, Eu, Mg, Si, and Cl were adjusted to the charged molar ratios shown in Table 1 below. The chlorosilicate phosphor powders of the respective Examples and Comparative Examples were obtained in the same manner as in Example 1 except that the powder was weighed.

Comparative Example 4
Using the same raw materials as in Example 1, the feed amounts of these raw materials were set such that the molar ratio of Si was 4, and Ca, Eu, Mg, Si, and Cl were adjusted to the charged molar ratios shown in Table 1 below. A 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 Luminous Properties Luminescent properties of the obtained phosphors were measured. The emission characteristics of the phosphors were measured by using a spectrofluorometer (QE-2000, manufactured by Otsuka Electronics Co., Ltd.), irradiating each phosphor with light having an excitation light wavelength of 450 nm, and at room temperature (25 ° C ± 5 ° C). The emission spectrum in was measured. FIG. 2 is a diagram showing emission spectra of the phosphor of Example 3 and the phosphor of Comparative Example 1. The emission peak wavelength λp (nm) and the internal quantum efficiency (%) were determined from the obtained emission spectrum. The internal quantum efficiency (%) was calculated by dividing the emitted light quantum number (%) by the absorbed light quantum number (%). The results are shown in Table 2 below.

Composition Analysis The composition analysis was performed on the obtained chlorosilicate phosphor. Each element of Ca, Mg, Si, and Eu of the chlorosilicate phosphor is an inductively coupled plasma emission spectrometer (ICP-AES: Inductively Coupled Plasma-Atomic Emission Spectrometry) (manufactured by Perkin Elmer, Optima 8300). The molar ratio of the elements was measured. In addition, the Cl element of the chlorosilicate phosphor was measured by using a potentiometric titrator (Kyoto Electronics Co., Ltd., AT-500N) to measure the molar ratio of the elements. In the composition of the phosphor, the molar ratio of each element other than Si was calculated based on the molar ratio of Si of 4. The results are shown in Table 2 below as "analysis molar ratio".

Particle size With respect to the obtained chlorosilicate phosphor, using a laser diffraction particle size distribution measuring device (manufactured by MALVERN, product name: MASTER SIZER 3000), the particle size at which the volume cumulative frequency from the small diameter side reaches 50% (volume median Diameter) was measured. The results are shown in Table 2 below.

  The phosphors of Examples 1 to 4 having emission peak wavelengths of 514 nm to 516 nm had higher internal quantum efficiency than the phosphors of Comparative Examples 1 and 2 having emission peak wavelengths of 514 nm to 515 nm. In the phosphors of Examples 1 to 4, the sum 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 suppressing the formation of the calcium silicate double phase. In addition, 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 the phosphor is It is speculated that the number of defects contained is small and, as a result, the internal quantum efficiency is high. Thus, the phosphors of Examples 1 to 4 had higher conversion efficiency of light from the light source than the phosphors of Comparative Examples 1 and 2.

  The phosphor of Example 5 having an emission peak wavelength of 521 nm had higher internal quantum efficiency than the phosphor of Comparative Example 3 having the same Eu molar ratio and emission peak wavelength. In the phosphor of Example 5, the total of the variable x that represents the molar ratio of Ca and the variable y that represents the molar ratio of Eu is in the range of 7.70 to 7.95 (7.70 ≦ x + y ≦ 7.95). It is speculated that the formation of the double phase of calcium silicate was suppressed, and as a result, the internal quantum efficiency was increased. Further, in the phosphor of Example 5, 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 included in the host crystal. It is presumed that the number of defects was small and, as a result, the internal quantum efficiency was high. Thus, the phosphor of Example 5 had higher conversion efficiency of light from the light source than the phosphor of Comparative Example 3.

  In the phosphor of Comparative Example 4, the sum of the variable x that represents the molar ratio of Ca and the variable y that represents the molar ratio of Eu exceeded 7.95, and the formation of the multiple phases of calcium silicate was not suppressed. It is speculated 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 For the obtained phosphor of Example 3, the contents of Sr, Ba and Al in the phosphor were measured using the same method as the composition analysis described above. The results are shown in Table 3 below.

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

Example 6
Using the chlorosilicate phosphor of Example 3, this chlorosilicate phosphor was used as a phosphor core, and SiO ₂ as a main component was adhered in the form of a film on the surface of the phosphor core. 180 ml of ethanol, 3.3 ml of an aqueous solution containing 3 mass% of ammonium chloride, 3.3 ml of an aqueous solution containing 3 mass% of calcium chloride, and 18 ml of ammonium water containing ammonium with respect to 100 g of the phosphor core. A mixed mother liquor of 30 ml was prepared. The phosphor core was placed in the mother liquor and stirred to disperse the phosphor core in the mother liquor, and the liquid temperature of the mother liquor was maintained at 45 ° C to 55 ° C. A liquid containing 23.2 g of tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ) in terms of silica is used as liquid A, 22.3 ml of ammonia water containing 18 mass% ammonia, 22.3 ml of deionized water, and 3 mass. A solution B containing 1.5 ml of an aqueous solution containing ammonium chloride was prepared. While stirring the mother liquor, the A liquid was 5.6 ml / min and the B liquid was 2.2 ml / min for a dripping time of 160 minutes to form a mixed liquid by dropping into the mother liquor, and after the dropping of the A liquid and the B liquid was completed. 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 dried on the surface of the phosphor core. A powder of the chlorosilicate phosphor of Example 6 having SiO ₂ adhered was obtained.

Comparative Example 5
Chlorosilicate of Comparative Example 5 in which SiO ₂ was attached 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 phosphor was used as the phosphor core. A phosphor powder was obtained.

  With respect to the phosphor of Example 6 and the phosphor 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 phosphor of Example 6 had higher internal quantum efficiency than the phosphor of Comparative Example 5. As shown in FIG. 3, the emission spectrum of the phosphor of Example 6 had 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 these results, 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. Phosphor of Example 6, because it is chlorosilicate phosphor surface of the phosphor deposited SiO ₂ film-shaped is core having a chemical composition represented by formula (I), the SiO ₂ of the membrane-like As a protective film, deterioration is suppressed and durability is increased.

Light-Emitting Device Example 7
A light emitting device of the embodiment shown in FIG. 1 was manufactured. The chlorosilicate phosphor of Example 6 was used as the first phosphor, Y ₃ Al ₅ O ₁₂ : Ce was used as the second phosphor, and (Sr, Ca) AlSiN ₃ : Eu was used as the third phosphor. A nitride-based semiconductor light emitting device having an emission peak wavelength of 456 nm was used as the light emitting device. The compounding amount of each phosphor is adjusted so that the light from the light emitting element, the first phosphor, the second phosphor, and the third phosphor has a correlated color temperature of 5000 K. A resin composition containing two phosphors, a third phosphor, and a silicone resin is prepared, and the resin composition is placed by dripping (potting) in the concave portion of the molded body using a dispenser, A light emitting device having a fluorescent member obtained by curing a 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 phosphor.

Relative Luminous Flux Using the total luminous flux measuring device using an integrating sphere, the luminous flux of each of the light emitting devices of Example 7 and Comparative Example 6 was measured. The luminous flux of the light emitting device of Comparative Example 6 was set to 100%, and the relative luminous flux of the light emitting device of Example 7 was calculated. The results are shown in Table 5.

  The light emitting device of Example 7 had a higher relative luminous flux at a correlated color temperature of 5000 K than the light emitting device of Comparative Example 6.

Example 8
Using the chlorosilicate phosphor of Example 3 as a phosphor core, tetraethoxysilane (Si (OC ₂ H ₅ ) ₄ ) was changed to silica in the same manner as in Example 6 except that the amount was changed to 6.8 g. A powder of the chlorosilicate phosphor of Example 8 in which SiO ₂ was attached to the surface of the body core was obtained.

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

The emission peak wavelength and internal quantum efficiency of the chlorosilicate phosphor of Example 8 in which SiO ₂ was attached to the surface were almost the same as those of 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.

Relative Luminous Flux With respect to the light emitting device of Example 9, the luminous flux was measured using a total luminous flux measuring device using an integrating sphere. The light flux of the light emitting device of Comparative Example 6 was set to 100%, and the relative light flux of the light emitting device of Example 9 was calculated. 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 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 the potted resin composition is used. It is presumed that it was unevenly arranged 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 emission side in the fluorescent member of the light emitting device, the light whose wavelength is converted by the chlorosilicate phosphor is absorbed by the second phosphor and the third phosphor. It was speculated that it would be hard to be done. 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 phosphor 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 illumination. 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 traffic signal, an illumination switch, various sensors, various indicators, a compact strobe, and the like.

  10: light emitting element, 20: first lead, 30: second lead, 40: molded body, 50: fluorescent member, 60 wire, 70: phosphor, 71: first phosphor, 72: second phosphor , 73, third phosphor, 100: light emitting device.

Claims (10)

  When it has a chemical composition containing Ca, Eu, Mg, Si, O, and Cl, and the molar ratio of Si in 1 mole of the chemical composition is 4, Ca is 7.0 or more and 7.94 in molar ratio. In the following range, Eu in a molar ratio of 0.01 to 1.0, the total of Ca and Eu in a molar ratio of 7.70 to 7.95, and Mg in a molar ratio of 0. A chlorosilicate phosphor containing Cl in a range of 9 or more and 1.1 or less in a molar ratio of more than 1.90 and 2.00 or less. The chlorosilicate phosphor according to claim 1, 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. (Numbers satisfying 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, 1.90 <b ≦ 2.00.)   In formula (I), x, y, a, and b are numbers satisfying 7.80 ≦ x + y ≦ 7.95, 15.73 ≦ a ≦ 16.05, and 1.95 ≦ b <2.00, respectively. The chlorosilicate phosphor according to claim 2, which is A phosphor core, which is an oxide having the above chemical composition, and at least one oxide selected from the group consisting of Al ₂ O ₃ , SiO ₂ , ZrO _2, and TiO ₂ are attached to the surface of the phosphor core. The chlorosilicate phosphor according to any one of claims 1 to 3, which is produced.   A light emitting device comprising a light source having an emission peak wavelength within a range of 250 nm or more and 485 nm or less and the chlorosilicate phosphor according to any one of claims 1 to 4. Preparing a compound containing Ca, a compound containing Eu, a compound containing Mg, a compound containing Si and a compound containing Cl, and a group consisting of a compound containing Eu, a compound containing Mg and a compound containing Si At least one compound selected from is an oxide, the compound containing Cl may contain Ca or Mg,
When Si in the compound containing Si is 4 mol, the molar ratio of Ca is 7 or more and 8.2 or less, the molar ratio of Eu is 0.01 or more and 1.1 or less, and the molar ratio of Mg is The ratio is 0.9 or more and 1.1 or less, the sum of Ca and Eu is 8.05 or more and 8.25 or less, and the Cl molar ratio is 2.0 or more and 3.0 or less. Each compound is weighed so as to be inside, and mixed to obtain a raw material mixture,
Firing the raw material mixture,
A method for producing a phosphor, which comprises obtaining a chlorosilicate phosphor. The method for producing a phosphor according to claim 6, wherein the chlorosilicate phosphor has 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. (Numbers satisfying 0.9 ≦ z ≦ 1.1, 15.6 ≦ a ≦ 16.1, 1.90 <b ≦ 2.00.)   The method for producing a phosphor according to claim 6, wherein the firing temperature is in the range of 1000 ° C. or higher and 1300 ° C. or lower.   The method for producing a phosphor according to claim 6, wherein the firing atmosphere is a reducing atmosphere. Comprising using the chlorosilicate phosphor as a phosphor core, and depositing at least one oxide selected from the group consisting of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and TiO _{2 on the} phosphor core. A method for producing the phosphor according to claim 6.

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