JP7086786B2 - Alminate phosphor and light emitting device - Google Patents

Description

The present invention relates to an aluminate phosphor and a light emitting device.

Various light emitting devices that emit light in white, light bulb color, orange color, etc. by combining a light emitting diode (LED) and a phosphor have been developed. In these light emitting devices, a desired light emitting color can be obtained by the principle of light color mixing. As a light emitting device, it is also known that a light emitting element that emits blue light as an excitation light source and a phosphor that emits green light and a phosphor that emits red light when excited by the light from the light source are combined to emit white light. Has been done. These light emitting devices are required to be used in a wide range of fields such as general lighting, in-vehicle lighting, displays, and liquid crystal backlights.

As a fluorescent substance that emits green light used in a light emitting device, for example, Patent Document 1 discloses a manganese-activated aluminate phosphor whose composition is (Ba, Sr) MgAl ₁₀ O ₁₇ : Mn ²⁺ . ing.

Japanese Unexamined Patent Publication No. 2004-155907

However, the manganese-activated aluminate phosphor disclosed in Patent Document 1 has high emission luminance when excited by vacuum ultraviolet rays, and is in the range of 430 nm or more and 485 nm or less (hereinafter, also referred to as “blue region”). When combined with a light emitting element having a light emitting peak wavelength in), the light emitting brightness is not sufficient.
Therefore, an object of the present invention is to provide an aluminate phosphor and a light emitting device having high light emission intensity by photoexcitation in the blue region.

The present invention includes the following aspects.
The first aspect of the present invention is an aluminate phosphor having a composition represented by the following formula (I).
X ¹ _p Eu _t Mg _q Mn _r Al _{s Op + t + q + r + 1.5s} (I)
(In formula (I), X ¹ is at least one element selected from the group consisting of Ba, Sr and Ca, and p, q, r, s and t are 0.5 ≦ p ≦ 1.0. , 0≤q <0.6, 0.4 <r≤0.7, 8.5≤s≤13.0, 0 <t <0.3, 0.5 <p + t≤1.2, 0.4 <A number that satisfies q + r ≦ 1.1.)

A second aspect of the present invention is a light emitting device including a fluorescent member containing the aluminate phosphor and an excitation light source.

According to one aspect of the present invention, it is possible to provide an aluminate phosphor having a high emission intensity and a light emitting device capable of efficiently wavelength-converting light in a blue region.

FIG. 1 is a schematic cross-sectional view showing an example of a light emitting device. FIG. 2 is an emission spectrum of the relative emission intensity (%) with respect to the wavelength of the aluminate phosphor according to Reference Example 1 and the aluminate phosphor according to Comparative Example 1. FIG. 3 is a reflection spectrum of the reflectance (%) with respect to the wavelength of the aluminate phosphor according to Example 3 and the aluminate phosphor according to Comparative Examples 1 to 3. FIG. 4 is an SEM photograph of the aluminate phosphor according to Reference Example 1. FIG. 5 is an SEM photograph of the aluminate phosphor according to Comparative Example 1.

Hereinafter, the aluminate phosphor and the light emitting device according to the embodiment of the present invention will be described. 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 aluminate phosphors and light emitting devices using the same. 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.

Alminate Fluorescent Material The first embodiment of the present invention is an aluminate phosphor having a composition represented by the following formula (I).
X ¹ _p Eu _t Mg _q Mn _r Al _{s Op + t + q + r + 1.5s} (I)
(In formula (I), X ¹ is at least one element selected from the group consisting of Ba, Sr and Ca, and p, q, r, s and t are 0.5 ≦ p ≦ 1.0. , 0≤q <0.6, 0.4 <r≤0.7, 8.5≤s≤13.0, 0 <t <0.3, 0.5 <p + t≤1.2, 0.4 <A number that satisfies q + r ≦ 1.1.)

In the formula (I), it is preferable that X ¹ contains Ba. In the above formula ( ^I ), the aluminate phosphor contains Ba in the above formula (I), so that the emission intensity due to photoexcitation in the blue region can be increased.

The variable p in the formula (I) is the total molar ratio of at least ^one element X1 selected from the group consisting of Ba, Sr and Ca. The term "molar ratio" refers to the molar amount of an element in one mole of the chemical composition of an aluminate phosphor. When the variable p does not satisfy 0.5 ≦ p ≦ 1.0 in the formula (I), an aluminate fluorophore having a composition represented by the formula (I) (hereinafter, “aluminate”). The crystal structure of (sometimes referred to as “fluorescent material (I)”) may become unstable, and the emission intensity may decrease. The variable p is preferably 0.60 or more, more preferably 0.80 or more. The variable p may be 0.999 or less.

The variable q in the formula (I) is the molar ratio of Mg. In the above formula (I), when the variable q is 0.6 or more, the molar ratio of Mg is high, the amount of Mn or Eu as an activating element is relatively small, and the aluminate phosphor (I) Emission intensity tends to decrease. The variable q in the formula (I) is preferably 0.05 ≦ q ≦ 0.55, more preferably 0.10 ≦, from the viewpoint of obtaining stability of the crystal structure and high emission intensity in a desired excitation wavelength region. It is a number satisfying q ≦ 0.55. The variable q in the formula (I) is more preferably 0.15 or more. When the variable q in the formula (I) is a number satisfying 0 ≦ q <0.6, the aluminate phosphor (I) emits light in a range of 510 nm or more and 525 nm or less due to photoexcitation in the blue region. It has a peak wavelength and can increase the emission intensity.

The variable r in the formula (I) is the molar ratio of Mn. Mn is an activating element of the aluminate phosphor (I). The aluminate phosphor (I) contains both Mn and Eu as an activating element. The almate phosphor (I) contains both Mn and Eu, and the light in the blue region from the excitation light source causes Eu to absorb the light to excite electrons, and the excitation energy is transferred from Eu to Mn. Further, it is presumed that it contributes to the emission of Mn. Since the aluminate phosphor (I) contains both Mn and Eu as activating elements, the emission intensity can be increased by photoexcitation in the blue region. In the above formula (I), when the variable r exceeds 0.7, the amount of activation of Mn becomes too large, and the aluminate phosphor (I) tends to undergo concentration quenching and the emission intensity tends to be low. .. In the formula (I), the variable r is preferably a number satisfying 0.45 ≦ r ≦ 0.65.

The variable t in the formula (I) is the molar ratio of Eu, which is the activating element of the aluminate phosphor (I). When the variable t exceeds 0.3, the emission intensity tends to decrease. When the variable t is 0, that is, when Eu is not contained in the aluminate phosphor (I), the light absorption in the blue region by Eu is eliminated and the transfer of excitation energy from Eu to Mn is eliminated, so that due to Mn. The emission intensity of the alumate phosphor is reduced. When the aluminate phosphor (I) contains Eu, the light absorption in the blue region becomes large, and the light emitting device using the aluminate phosphor (I) efficiently converts the light emitted from the light emitting element into wavelength. can do. Therefore, in the aluminate phosphor (I) according to the embodiment of the present invention, the amount of the phosphor in the light emitting device is reduced, and the light emitting device can be miniaturized. In the formula (I), the variable t is preferably 0.001 ≦ t ≦ 0.250, more preferably 0.001 ≦ t ≦ 0.225, and further preferably 0.001 ≦ t ≦ 0.200. ..

The sum of the variable p and the variable t in the formula (I) (hereinafter, may be referred to as “variable p + t”) is of at least one element X ¹ and Eu selected from the group consisting of Ba, Sr and Ca. The total molar ratio. If the variable p + t is less than 0.5 or more than 1.2, the crystal structure of the aluminate phosphor (I) tends to be unstable, and the emission intensity may decrease. The variable p + t is preferably 0.55 or more, more preferably 0.60 or more. The variable p + t is preferably 1.15 or less, more preferably 1.10 or less.

The sum of the variable q and the variable r in the formula (I) (hereinafter, may be referred to as “variable q + r”) is the molar ratio of the sum of Mg and Mn. When the variable q + r is 0.4 or less or more than 1.1, the crystal structure of the aluminate phosphor (I) tends to be unstable, and sufficient emission intensity may not be obtained. The variable q + r is preferably 0.4 <q + r ≦ 1.0, more preferably 0.5 or more, and more preferably 0.55 or more.

The sum of the variable r and the variable t in the formula (I) (hereinafter, may be referred to as “variable r + t”) is the molar ratio of the sum of the activating elements Mn and Eu, and is 0.4 <r + t <. It is preferably 0.8. When the variable r + t is 0.8 or more, concentration quenching occurs, for example, when excited by light in the blue region, and the emission intensity tends to be low. In the above formula (I), when the variable r + t is 0.4 or less, the activation amount is small, and the aluminate phosphor (I) absorbs less light when excited by light in the blue region. , It may be difficult to increase the emission intensity.

The variable s in the formula (I) is the molar ratio of Al. When the variable s is less than 8.5 or more than 13.0, the crystal structure becomes unstable, and the aluminate phosphor (I) emits light intensity when excited by light in the near-ultraviolet to blue region. Tends to decrease. In the formula (I), the variable s is preferably a number satisfying 9.0 ≦ s ≦ 13.0. In the formula (I), the variable s is more preferably 12.0 or less, still more preferably 11.0 or less.

The almate phosphor (I) may be produced by using a flux such as a halide in order to enhance the reactivity of the raw material. In this case, when a flux containing an alkali metal is used, a trace amount of the alkali metal element may be detected from the aluminate phosphor (I). Even in such a case, the alkali metal element contained in the aluminate phosphor (I) is 100 ppm or more and 1000 ppm or less, may be 200 ppm or more, may be 300 ppm or more, and may be 990 ppm or less. May be. Further, the aluminate phosphor (I) has a composition represented by the above formula (I) even when a trace amount of alkali metal element is detected. Further, when a halide containing an element constituting the composition represented by the formula (I) is used, the halide becomes a raw material constituting the aluminate phosphor (I) and also acts as a flux. .. When both a halogenated product containing an element constituting the composition represented by the formula (I) and a compound containing an element other than the halogenated product constituting the composition represented by the formula (I) are used, the above is used. The molar ratio of the elements constituting the composition represented by the formula (I) contained in the halogenated product and the molar ratio of the elements constituting the composition represented by the formula (I) contained in the compound other than the halogenated product. Halogen and compounds other than the halogen can be used so that the sum of the above satisfies the molar ratio of each element represented by the formula (I). As long as the composition represented by the formula (I) is satisfied, the element constituting the aluminate phosphor (I) may be an element derived from flux.

Average particle size D
The aluminate phosphor (I) preferably has an average particle size D of 10 μm or more as measured by the FSSS (Fisher Sub-Sieve Sizer) method. The average particle size D of the aluminate phosphor (I) measured by the FSSS method is more preferably 10.5 μm or more. Since the almate phosphor (I) has a large average particle size D of 10 μm or more, it can absorb light from an excitation light source well and can further increase the emission intensity. The FSSS method is a kind of air permeation method, and is a method of measuring the specific surface area by utilizing the flow resistance of air to determine the particle size. The average particle size D by the FSSS method can be measured by using, for example, Fisher Sub-Sieve Sizer Model 95 (manufactured by Fisher Scientific). The average particle size D of the aluminate phosphor (I) measured by the FSSS method is preferably large, but is usually 50 μm or less, and is preferably 30 μm or less from the viewpoint of ease of production.

Volume average particle size D50
The volume average particle size D50 of the almate phosphor (I) having a volume accumulation frequency of 50% from the small diameter side in the volume-based particle size distribution measured by the laser diffraction type particle size distribution measurement method is preferably 10 μm or more, more preferably. Is 12 μm or more, more preferably 15 μm or more. The laser diffraction type particle size distribution measuring method is a method of measuring the particle size without distinguishing between primary particles and secondary particles by using the scattered light of the laser light irradiating the particles. The volume average particle size D50 by the laser diffraction scattering type particle size distribution measuring method can be measured by using, for example, a laser diffraction type particle size distribution measuring device (MASTER SIZER 3000, manufactured by MAVERN). As for the average particle size D and the volume average particle size D50, the closer the two values are, the less the particles are aggregated. The volume-based volume average particle size D50 of the almate phosphor (I) by the laser diffraction / scattering type particle size distribution measurement method is usually 75 μm or less, preferably 65 μm or less, and more preferably 55 μm or less.

Light-emitting device An example of a light-emitting device according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a light emitting device 100 according to a second embodiment of the present invention. The light emitting device according to the second embodiment of the present invention includes a fluorescent member including the aluminate phosphor (I) and an excitation light source.

The light emitting device 100 includes a molded body 40, a light emitting element 10, and a fluorescent member 50. 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. The molded body 40 forms a recess having a bottom surface and a side surface, and the light emitting element 10 is placed on the bottom surface of the recess. 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, respectively, via a wire 60. The light emitting element 10 is covered with a fluorescent member 50. The fluorescent member 50 includes, for example, a phosphor 70 that converts the wavelength of light from the light emitting element 10 and a resin that also serves as a sealing material. Further, the fluorophore 70 includes a first fluorophore 71 and a second fluorophore 72. The first fluorescent substance 71 includes the aluminate phosphor (I) according to the first embodiment of the present invention. The first lead 20 and the second lead 30 connected to the pair of positive and negative electrodes of the light emitting element 10 are directed toward the outside of the package constituting the light emitting device 100, and the first lead 20 and the second lead 30 are directed to the outside. Part of is exposed. Through these first leads 20 and second leads 30, electric power can be supplied from the outside to cause the light emitting device 100 to emit light.

The light emitting element 10 is used as an excitation light source, and preferably has a light emitting peak wavelength in the range of 430 nm or more and 485 nm or less. The range of the emission peak wavelength of the light emitting element 10 is more preferably 440 nm or more and 480 nm or less, and further preferably 445 nm or more and 470 nm or less. The aluminate phosphor (I) according to the first embodiment of the present invention is efficiently excited by light from an excitation light source having an emission peak wavelength in the range of 430 nm or more and 485 nm or less, and has high emission intensity. By using the fluorescent member containing the aluminate phosphor (I), the light from the light emitting element is efficiently wavelength-converted, and the light from the light emitting element 10 and the phosphor 70 containing the aluminate phosphor (I) are included. It is possible to provide a light emitting device 100 that emits a mixed color light with the light from.

As the light emitting device 10, for example, it is preferable to use 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). By using a semiconductor light emitting device as an excitation light source of a light emitting device, it is possible to obtain a stable light emitting device having high efficiency, high output linearity with respect to input, and resistance to mechanical impact. The half width of the emission spectrum of the light emitting element 10 may be, for example, 30 nm or less, 25 nm or less, or 20 nm or less. The full width at half maximum is the full width at half maximum (FWHM) of the maximum emission peak in the emission spectrum, and the wavelength width of the emission peak indicating a value of 50% of the maximum value of the maximum emission peak in each emission spectrum. Say.

The first fluorescent substance 71 contains the aluminate phosphor (I) according to the first embodiment of the present invention, and is contained in the fluorescent member 50 that covers the light emitting element 10. In the light emitting device 100 in which the light emitting element 10 is covered with the fluorescent member 50 containing the first phosphor 71, a part of the light emitted from the light emitting element 10 is absorbed by the aluminate phosphor (I). It is emitted as green light. By using a light emitting element 10 that emits light having a light emitting peak wavelength in the range of 430 nm or more and 485 nm or less, it is possible to provide a light emitting device having high light emitting intensity.

The fluorescent member 50 preferably includes a second phosphor 72 having a different emission peak wavelength from the first phosphor 71. For example, the light emitting device 100 appropriately includes a light emitting element 10 that emits light having a light emitting peak wavelength in the range of 430 nm or more and 485 nm or less, and a first phosphor 71 and a second phosphor 72 excited by the light. As a result, a wide color reproduction range and high color playability can be obtained.

The second phosphor 72 may be any as long as it absorbs the light from the light emitting element 10 and converts the wavelength into light having a wavelength different from that of the first phosphor 71. For example, (Ca, Sr, Ba) ₂ SiO ₄ : Eu, (Ca, Sr, Ba) ₈ MgSi ₄ O ₁₆ (F, Cl, Br) ₂ : Eu, Si _6-z Al _{z Oz} N _8-z : Eu (0 <z≤4.2), (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, (Lu, Y, Gd, Lu) ₃ (Ga, Al) ₅ O ₁₂ : Ce, (La, Y, Gd) ₃ Si ₆ N ₁₁ : Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, CaSc ₄ O ₄ : Ce, K ₂ (Si, Ge, Ti) F ₆ : Mn, (Ca, Sr, Ba) ) ₂ Si ₅ N ₈ : Eu, CaAlSiN ₃ : Eu, (Ca, Sr) AlSiN ₃ : Eu, (Sr, Ca) LiAl ₃ N ₄ : Eu, (Ca, Sr) ₂ Mg ₂ Li ₂ Si ₂ N ₆ : Eu, 3.5MgO, _0.5MgF2 , _GeO2 : Mn and the like.

When the fluorescent member 50 includes the second phosphor 72, the second phosphor 72 is preferably a red phosphor that emits red light, and emits light having an emission peak wavelength in the range of 430 nm or more and 485 nm or less. It is preferable to absorb light and emit light having an emission peak wavelength in the range of 610 nm or more and 780 nm or less. By including the red phosphor in the light emitting device, it is possible to provide a light emitting device that emits desired light in a wide range of fields such as a lighting device and a liquid crystal display device.

Examples of the red phosphor include a Mn-activated phosphor having a composition represented by K ₂ SiF ₆ : Mn or 3.5 MgO / 0.5 MgF ₂ / GeO ₂ : Mn, CaSiAlN ₃ : Eu, (Ca, Sr) AlSiN ₃ : Eu or SrLiAl ₃ N ₄ : Eu activated nitride phosphor having a composition represented by Eu can be mentioned. Of these, the red phosphor is preferably a Mn-activated fluoride phosphor having a half-value width of 20 nm or less in the emission spectrum from the viewpoint of increasing the color purity and expanding the color reproduction range.

The fluorescent substance 70 including the first fluorescent substance 71 and the second fluorescent substance 72 constitutes a fluorescent member 50 that covers the light emitting element together with the sealing material. Examples of the sealing material constituting the fluorescent member 50 include thermosetting resins such as silicone resin and epoxy resin. The amount of the fluorescent substance 70 in the composition for a fluorescent member containing the fluorescent substance 70 for constituting the fluorescent member 50 and the resin is, for example, in the range of 10 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the resin. ..

Method for producing aluminate phosphor Next, an example of a method for producing an aluminate phosphor will be described. The method for producing the aluminate phosphor (I) is not limited to the following production method. The aluminate fluorophore (I) can be produced by using a compound containing an element constituting the composition of the aluminate fluorophore (I).

Raw material constituting the composition of the aluminate phosphor (I) As the raw material constituting the composition of the aluminate phosphor (I), at least ^one element X1 selected from the group consisting of Ba, Sr and Ca is used. Compounds containing (hereinafter, also referred to as " ^X1 compound"), compounds containing magnesium (Mg), compounds containing manganese (Mn), aluminum metals, aluminum alloys or compounds containing aluminum (Al), and uropyum (Eu). Examples include compounds containing.

Compounds containing the element X ¹ Examples of the X ¹ compound include oxides, hydroxides, carbonates, nitrates, sulfates, carboxylates, halides, nitrides and the like containing the element X ¹ . These compounds may be in the form of hydrates. The halide containing the element X ¹ also acts as a flux. Specifically, BaO, Ba (OH) 2.8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (OCO) _{2.2H 2} O, Ba ₍ OCOCH ₃ ) ₂ , BaCl ₂ . 6H ₂ O, Ba ₃ N ₂ , BaNH, SrO, Sr (OH) 2.8H ₂ O, SrCO ₃ , Sr (NO ₃ ) _{2.4H 2} O, SrSO ₄ , Sr _{(OCO) 2 ·} H ₂ O, Sr (OCOCH ₃ ) 2.0.5H ₂ O, SrCl 2.6H ₂ O, Sr ₃ N ₂ , SrNH, CaO, Ca (OH) ₂ , CaCO ₃ , Ca _{(NO 3) 2 , CaSO 4} , Ca ₍ OCO) ₂ , CaCl ₂ , Ca ₃ N ₂ and the like. These compounds may be used alone or in combination of two or more. Among these, carbonates and oxides are preferable because they are easy to handle. Since it has good stability in the air, is easily decomposed by heating, it is difficult for elements other than the target composition to remain, and it is easy to suppress the decrease in emission intensity due to residual impurity elements, carbonates containing element X ¹ are used. More preferred.

Compounds containing Mg Examples of compounds containing Mg include oxides containing Mg, hydroxides, carbonates, nitrates, sulfates, carboxylates, halides, nitrides and the like. These Mg-containing compounds may be in the form of hydrates. The halide containing Mg also acts as a flux. Specifically, MgO, Mg (OH) ₂ , 3MgCO ₃・ Mg (OH) 2.3H ₂ O, MgCO ₃・ Mg (OH) ₂ , Mg ₍ NO ₃ ) _{2.6H 2} O, Л ₄ , Mg (OCO) ₂ · H ₂ O, Mg (OCOCH ₃ ) 2.4H ₂ O, MgCl ₂ , Mg _{3 N 2 and} the like can be mentioned. As the compound containing Mg, one kind may be used alone, or two or more kinds may be used in combination. Among these, carbonates or oxides are preferable because they are easy to handle. Oxide containing Mg (MgO) because it has good stability in the air, is easily decomposed by heating, it is difficult for elements other than the target composition to remain, and it is easy to suppress the decrease in emission intensity due to residual impurity elements. ) And / or a halide that also acts as a flux (eg, MgF ₂ ) is more preferred.

Compounds containing Mn Examples of the compound containing Mn include oxides containing Mn, hydroxides, carbonates, nitrates, sulfates, carboxylates, halides, nitrides and the like. The halide containing Mn also acts as a flux. These Mn-containing compounds may be in the form of hydrates. Specifically, MnO ₂ , Mn ₂ O ₂ , Mn ₃ O ₄ , Mn O, Mn (OH) ₂ , MnCO ₃ , Mn (NO ₃ ) ₂ , Mn (OCOCH ₃ ) _{2.2H 2 O} , Mn (OCOCH). ₃ ) Examples include _{3.2H 2} O and MnCl _{2.4H 2} O. As the compound containing Mn, one kind may be used alone, or two or more kinds may be used in combination. Among these, carbonates and oxides are preferable because they are easy to handle. It has good stability in the air, is easily decomposed by heating, it is difficult for elements other than the target composition to remain, and it is easy to suppress the decrease in emission intensity due to residual impurity elements. , MnCO ₃ ) is more preferable.

Compounds containing Eu Examples of compounds containing Eu include oxides containing Eu, hydroxides, carbonates, nitrates, sulfates, halides, nitrides and the like. The halide containing Eu also acts as a flux. These Eu-containing compounds may be in the form of hydrates. Specific examples thereof include EuO, Eu ₂ O ₃ , Eu (OH) ₃ , Eu ₂ (CO ₃ ) ₃ , Eu (NO ₃ ) ₃ , Eu ₂ (SO ₄ ) ₃ , EuCl ₂ , EuF ₃ and the like. .. As the compound containing Eu, one kind may be used alone, or two or more kinds may be used in combination. Among these, carbonates and oxides are preferable because they are easy to handle. It has good stability in the air, is easily decomposed by heating, elements other than the target composition are unlikely to remain, and it is easy to suppress the decrease in emission intensity due to residual impurity elements. Therefore, an oxide containing Eu (for example, , Eu ₂ O ₃ ) is more preferable.

Al metal, Al alloy or compound containing Al Examples of the compound containing Al include oxides containing Al, hydroxides, nitrides, oxynitrides, fluorides, chlorides and the like. The halide containing Al also acts as a flux. These compounds may be hydrates. Aluminum metal or aluminum alloy may be used. Al metal or Al alloy may be used instead of at least a part of the compound.
Specific examples of the compound containing Al include Al ₂ O ₃ , Al (OH) ₃ , AlN, AlF ₃ , AlCl ₃ , and the like. As the compound containing Al, one kind may be used alone, or two or more kinds may be used in combination. The compound containing Al is preferably an oxide (for example, Al ₂ O ₃ ). This is because the oxide does not contain any element other than the target composition of the aluminate phosphor as compared with other materials, and it is easy to obtain the phosphor having the target composition. Further, when a compound containing an element other than the target composition is used, a residual impurity element may be present in the obtained phosphor, and this residual impurity element becomes a killer element for light emission, and the light emission intensity becomes high. There is a risk that it will drop significantly.

Flux It is preferable to use flux in order to increase the reactivity of the raw material. Examples of the flux include halides. By containing the flux in the raw material mixture, the reaction between the raw materials is promoted, and the solid phase reaction is likely to proceed more uniformly. It is considered that this is because the temperature at which the raw material mixture is heat-treated is approximately the same as the formation temperature of the liquid phase of the halide used as the flux, or is higher than the formation temperature of the liquid phase, so that the reaction is promoted. Be done.
The halide is selected from the group consisting of fluorides containing at least one metal element selected from the group consisting of rare earth metals, alkaline earth metals, and alkali metals, rare earth metals, alkaline earth metals, and alkali metals. Examples thereof include chlorides containing at least one metallic element, fluorides of aluminum, or chlorides. When a compound containing an element constituting the composition of the aluminate phosphor (I) is used as the flux, the composition of the aluminate phosphor is such that the element ratio of the cations contained in the flux is the target. As a compound, a flux can be added, or each raw material can be prepared so as to have the desired composition of the aluminate phosphor, and then the flux can be further added.
In the case of a flux containing elements constituting the composition of the almate phosphor (I), the total of the molar ratio of the elements contained in the flux and the molar ratio of the elements contained in the compound other than the flux is the above formula. The flux and other compounds are mixed so as to satisfy the composition represented by (I).
In the case of a flux that does not contain the elements constituting the composition of the aluminate phosphor (I), the flux is added after preparing each raw material so as to have the desired composition of the aluminate phosphor (I). do.
When a halide containing an alkali metal is used as a flux, a trace amount of an alkali metal element may be contained in the obtained aluminate phosphor. The alkali metal element contained in the almate phosphor is preferably at least one element selected from the group consisting of Li, K and Na, and more preferably Na.

Specific examples of the flux include BaF ₂ , MgF ₂ , CaF ₂ , LiF, NaF, KF, and AlF ₃ . The flux is preferably at least one selected from the group consisting of MgF ₂ , NaF, and AlF ₃ , and more preferably MgF ₂ and / or NaF. This is because by using MgF ₂ and / or NaF for the flux, the crystal structure is stabilized and a phosphor having a relatively large average particle size can be obtained. As the flux, one type may be used alone, or two or more types may be used in combination.

When a halide containing an element other than the elements constituting the composition of the almate phosphor (I) is used as the flux, the content of the flux is based on 100 parts by mass in total of each raw material before containing the flux. It is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, further preferably 2 parts by mass or less, and preferably 0.1 part by mass or more. When the flux content containing elements other than the elements constituting the composition of the almate phosphor (I) is in the above range, it does not become difficult to form a crystal structure due to insufficient particle growth due to the small amount of flux. Also, the amount of flux is not too large to make it difficult to form a crystal structure.

Mixing of Raw Materials Each raw material is weighed so as to have a molar ratio satisfying the composition of the above formula (I), and then mixed to produce a raw material mixture. A halide may be added to the raw material mixture as a raw material and / or a flux. The amount of the halide in the raw material mixture is preferably 1 mol with respect to the total of 1 mol of the element amount selected from the group consisting of Ba, Ca and Sr contained in the raw material mixture and the elemental amount of Eu. Hereinafter, it is preferably 0.5 mol or less, more preferably 0.2 mol or less, and preferably 0.05 mol or more. Here, when two or more kinds of halides are added as two or more kinds of fluxes, the amount of the flux in the raw material mixture is preferably in the above range as the total molar amount of the two kinds of fluxes.

The raw material mixture may be pulverized and mixed using a dry crusher such as a ball mill, a vibration mill, a hammer mill, a roll mill, or a jet mill, or may be pulverized and mixed using a milk bowl and a milk stick, for example, a ribbon blender. Mixing may be performed using a mixer such as a Henschel mixer or a V-type blender, or pulverization and mixing may be performed using both a dry crusher and a mixer. Further, the mixing may be a dry type mixing, or a wet mixing method may be performed by adding a solvent or the like. The mixing is preferably drywall mixing. This is because the dry type can shorten the process time and improve the productivity than the wet type.

Heat treatment (first heat treatment)
The raw material mixture is placed in a carbon material such as graphite, a crucible made of boron nitride (BN), aluminum oxide (alumina), tungsten (W), molybdenum (Mo), a boat, etc. and heat-treated to form an aluminate phosphor (aluminate phosphor). I) can be obtained. The step of heat-treating the raw material mixture is also referred to as heat treatment or first heat treatment.

The temperature for heat treatment (first heat treatment) is preferably 1000 ° C. or higher and 1800 ° C. or lower, more preferably 1100 ° C. or higher and 1750 ° C. or lower, and further preferably 1200 ° C. or higher and 1700 ° C. or lower, particularly preferably, from the viewpoint of stability of the crystal structure. It is preferably 1300 ° C. or higher and 1650 ° C. or lower.

The heat treatment time varies depending on the rate of temperature rise, the heat treatment atmosphere, etc., and is preferably 1 hour or longer, more preferably 2 hours or longer, still more preferably 3 hours or longer, preferably 20 hours or shorter, more preferably after reaching the heat treatment temperature. It is preferably 18 hours or less, more preferably 15 hours or less.

The atmosphere for heat treatment can be an inert atmosphere such as argon or nitrogen, a reducing atmosphere containing hydrogen or the like, or an oxidizing atmosphere such as in the atmosphere. The raw material mixture is preferably heat-treated in a reducing nitrogen atmosphere to obtain a phosphor. The atmosphere for heat-treating the raw material mixture is more preferably a nitrogen atmosphere containing reducing hydrogen gas.
The raw material mixture has improved reactivity of the raw material mixture in a highly reducing atmosphere such as a reducing atmosphere containing hydrogen and nitrogen, and is heat-treated under atmospheric pressure without pressurization to obtain an aluminate phosphor (aluminate phosphor. I) can be obtained. For the heat treatment, for example, an electric furnace, a gas furnace, or the like can be used.

The obtained aluminate fluorophore (I) may be used as a seed crystal, further mixed with raw materials, and subjected to a second heat treatment to obtain the aluminate fluorophore (I). When the obtained aluminate phosphor (I) is used as a seed crystal and further subjected to the second heat treatment, the step of obtaining the aluminate phosphor (I) to be the seed crystal is also referred to as the first heat treatment.

Dispersion Treatment The first fired product may be subjected to a dispersion treatment by a dispersion treatment step described later after the first heat treatment and before the second heat treatment. In the dispersion treatment step performed on the first fired product, for example, the first fired product is classified by wet dispersion, wet sieving, dehydration, drying, dry sieving, etc., and the seed has the desired average particle size. The aluminate phosphor (I) to be crystallized may be obtained. As the solvent used for wet dispersion, for example, deionized water can be used. The time for wet dispersion varies depending on the solid dispersion medium and solvent used, but is preferably 30 minutes or longer, more preferably 60 minutes or longer, still more preferably 90 minutes or longer, still more preferably 120 minutes or longer, and preferably 420 minutes or longer. Less than a minute. The aluminate phosphor (I) to be a seed crystal is preferably used in a light emitting device when the aluminate phosphor obtained by wet dispersion is performed in a range of 30 minutes or more and 420 minutes or less. Dispersibility in the resin constituting the fluorescent member can be improved.

Second heat treatment The aluminate phosphor (I) obtained in the first heat treatment is used as a seed crystal, and a raw material is further added to the aluminate phosphor (I) which is the seed crystal to perform the second heat treatment. conduct. The second mixture containing the aluminate phosphor (I) obtained by the first heat treatment and the raw material contains a compound containing at least one metal element selected from the group consisting of Ba, Sr and Ca, and a compound containing at least one metal element. The first fired product having a content of at least one of a compound containing Mn and a compound containing Eu, a compound containing Al, and a content of 10% by mass or more and 90% by mass or less with respect to the total amount of the second mixture is required. It contains a compound containing Mg depending on the above. The second mixture is subjected to the second heat treatment to obtain the aluminate phosphor (I) which has been subjected to the second heat treatment. The second mixture preferably contains a compound containing Eu and a compound containing Mn.

The content of the aluminate phosphor (I) as a seed crystal contained in the second mixture is preferably 15% by mass or more and 85% by mass or less, more preferably, with respect to the total amount of the second mixture. It is 20% by mass or more and 80% by mass or less, more preferably 25% by mass or more and 80% by mass or less, and even more preferably 30% by mass or more and 80% by mass or less. When the aluminate phosphor (I) to be a seed crystal is contained in the second mixture in the range of 10% by mass or more and 90% by mass or less with respect to the total amount of the second mixture, the second In the heat treatment of the above, crystal growth is promoted from the seed crystal aluminate phosphor (I), and the average particle size measured by the FSSS method is larger than that of the seed crystal aluminate phosphor (I). The aluminate phosphor (I) subjected to the second heat treatment can be obtained.

When mixing the second mixture, the mixing method, the mixer and the like exemplified in the case of obtaining the first mixture can be used. Further, the second mixture can be heat-treated by putting it in a crucible, a boat or the like made of the same material as the raw material mixture.

The second mixture preferably contains a flux, and the second fired product can be obtained by performing a second heat treatment together with the flux contained in the second mixture.

As the second heat treatment temperature, a temperature in the same range as the first heat treatment temperature described above can be applied. The second heat treatment temperature may be the same as or different from the first heat treatment temperature described above. For the heat treatment, for example, an electric furnace, a gas furnace, or the like can be used.

As the atmosphere of the second heat treatment, the same atmosphere as the above-mentioned first heat treatment atmosphere can be applied. The second heat treatment atmosphere may be the same atmosphere as the first heat treatment atmosphere described above, or may be a different atmosphere.

As the second heat treatment time, a time in the same range as the first heat treatment time described above can be applied. The second heat treatment time may be the same as or different from the first heat treatment time described above.

Post-treatment The obtained fluorescent material may be wet-dispersed and subjected to post-treatment such as wet sieving, dehydration, drying, and dry sieving. By these post-treatments, a fluorescent material having a desired average particle size can be obtained. .. For example, the heat-treated phosphor is dispersed in a solvent, the dispersed phosphor is placed on a sieve, and the solvent flow is passed through the sieve while applying various vibrations to allow the calcined product to pass through a mesh. Wet sieving is performed, then dehydration, drying, and dry sieving to obtain a phosphor having a desired average particle size.
By dispersing the phosphor after the heat treatment in the medium, impurities such as the calcination residue of the flux and unreacted components of the raw material can be removed. A dispersion medium such as alumina balls or zirconia balls may be used for wet dispersion.

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

Reference example 1
BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and flux as a phosphor having a composition represented by Ba _0.999 Eu _0.001 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ . MgF ₂ which also acts as a raw material is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.999: 0.001: 0.5: 0.5: 10. As a halide acting as a flux, NaF was added in addition to MgF ₂ to obtain a raw material mixture. 0.26 parts by mass of NaF was added to a total of 100 parts by mass of each raw material before the flux was added. The obtained raw material mixture is filled in an alumina crucible, covered, and heat-treated at 1500 ° C. for 5 hours in a mixed atmosphere of ₃ % by volume of H2 and 97% by volume of _N2 to form an aluminate. A phosphor was obtained.

Example 2
As a phosphor having a composition represented by Ba _0.97 Eu _0.03 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.97: 0.03: 0.5: 0.5: 10 was used.

Example 3
As a phosphor having a composition represented by Ba _0.95 Eu _0.05 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.95: 0.05: 0.5: 0.5: 10 was used.

Example 4
As a phosphor having a composition represented by Ba _0.90 Eu _0.10 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.90: 0.10: 0.5: 0.5: 10 was used.

Comparative Example 1
As a phosphor having a composition represented by Ba _1.0 Mg _0.8 Mn _0.2 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Mg: Mn: Al = 1.0: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having a ratio of 0.8: 0.2: 10 was used.

Comparative Example 2
As a phosphor having a composition represented by Ba _1.0 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Mg: Mn: Al = 1.0: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having a ratio of 0.5: 0.5: 10 was used.

Comparative Example 3
As a phosphor having a composition represented by Ba _0.70 Eu _0.30 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.70: 0.30: 0.5: 0.5: 10 was used.

Comparative Example 4
As a phosphor having a composition represented by Ba _0.60 Eu _0.40 Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.60: 0.40: 0.5: 0.5: 10 was used.

Comparative Example 5
As a phosphor having a composition represented by Ba _0.60 Eu _0.40 Mg _0.7 Mn _0.3 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.60: 0.40: 0.7: 0.3: 10 was used.

Comparative Example 6
As a phosphor having a composition represented by Ba _0.60 Eu _0.40 Mg _0.8 Mn _0.2 Al ₁₀ O ₁₇ , the molar ratio as the charging amount ratio of each raw material is Ba: Eu: Mg: Mn: An aluminate phosphor was obtained by the same method as in Reference Example 1 except that the raw material having Al = 0.60: 0.40: 0.8: 0.2: 10 was used.

Reference example 5
As a phosphor having a composition represented by Ba _0.9 Eu _0.1 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.9: 0.1: 0.45: 0.5: It was mixed so as to be 10, and NaF was added in addition to MgF ₂ as a halide acting as a flux to obtain a raw material mixture. 0.26 parts by mass of NaF was added to a total of 100 parts by mass of each raw material before the flux was added. The obtained raw material mixture was filled in an alumina crucible, covered with a lid, and subjected to the first heat treatment at 1500 ° C. for 5 hours in a mixed atmosphere containing ₃ % by volume of H2 and 97% by volume of _N2 . , An aluminate phosphor to be a seed crystal was obtained. The obtained aluminate phosphor as a seed crystal was placed in a polyethylene container, dispersed in deionized water, dispersed for 240 minutes using alumina balls as a dispersion medium, and then wet sieved, classified, dehydrated, and subjected to wet sieving, classification, and dehydration. Post-treatment was carried out in the order of drying and dry sieving to obtain an aluminate phosphor as a seed crystal.
_{BaCO _ _ _ _ _ 3} , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ , and MgF ₂ that also acts as a flux are used as raw materials, and NaF is added in addition to MgF ₂ as a halide that also acts as a flux. Was obtained. The second mixture was prepared so that the total amount (100% by mass) of the second mixture contained 30% by mass of the aluminate phosphor as a seed crystal. The obtained second mixture is filled in an alumina crucible, covered with a lid, and subjected to a second heat treatment at 1500 ° C. for 5 hours in a mixed atmosphere containing ₃ % by volume of H2 and 97% by volume of _N2 . As a result, a second heat-treated product was obtained. The obtained second heat-treated product was placed in a polyethylene container, dispersed in deionized water, dispersed for 240 minutes using alumina balls as a dispersion medium, and then wet sieved, classified, dehydrated, dried, and dried. Post-treatment was carried out in this order to obtain an aluminate phosphor.

Reference example 6
As phosphors having a composition represented by Ba _0.875 Eu _0.125 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.875: 0.125: 0.45: 0.5 :. An aluminate phosphor was obtained in the same manner as in Reference Example 5 except that the mixture was mixed so as to be 10.

Reference example 7
As phosphors having a composition represented by Ba _0.85 Eu _0.15 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.85: 0.15: 0.45: 0.5 :. An aluminate phosphor was obtained in the same manner as in Reference Example 5 except that the mixture was mixed so as to be 10.

Reference example 8
As phosphors having a composition represented by Ba _0.825 Eu _0.175 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.825: 0.175: 0.45: 0.5 :. An aluminate phosphor was obtained in the same manner as in Reference Example 5 except that the mixture was mixed so as to be 10.

Reference example 9
As phosphors having a composition represented by Ba _0.8 Eu _0.2 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.8: 0.2: 0.45: 0.5: An aluminate phosphor was obtained in the same manner as in Reference Example 5 except that the mixture was mixed so as to be 10.

Reference example 10
As phosphors having a composition represented by Ba _0.775 Eu _0.225 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 , BaCO ₃ , Eu ₂ O ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and the like. , MgF ₂ which also acts as a flux is used as each raw material, and the molar ratio as the charging amount ratio is Ba: Eu: Mg: Mn: Al = 0.775: 0.225: 0.45: 0.5 :. An aluminate phosphor was obtained in the same manner as in Reference Example 5 except that the mixture was mixed so as to be 10.

Comparative Example 7
BaCO ₃ , MgO, MnCO ₃ , Al ₂ O ₃ and Mg F ₂ which also acts as a flux are used as phosphors having a composition represented by Ba _1.0 Mg _0.45 Mn _0.5 Al ₁₀ O _16.95 . It is used as each raw material and mixed with reference example 5 so that the molar ratio as the charging amount ratio is Ba: Mg: Mn: Al = 1.0: 0.45: 0.5: 10. Similarly, an aluminate phosphor was obtained.

Light emitting device
The light emitting device 100 was manufactured by using the aluminate phosphors of Reference Examples 5 to 10 and Comparative Example 7 as the first phosphor 71. The light emitting device 100 uses a nitride semiconductor having a light emitting peak wavelength of 450 nm as the light emitting element 10. Silicone resin was used as the sealing material constituting the fluorescent member 50. As the second phosphor, a fluoride phosphor activated with manganese that emits red light was used. Silicone is used for the phosphor 70 containing the first phosphor 71 and the second phosphor 72 whose blending amounts are adjusted so that the chromaticity coordinates of the light emitted by the light emitting device are around x = 0.262 and y = 0.223. It was added to the resin, mixed and dispersed, and then defoamed to obtain a composition for a fluorescent member constituting the fluorescent member. Table 2 shows the amount (parts by mass) of the phosphor 70 with respect to 100 parts by mass of the silicone resin in each composition for fluorescent members. This composition for a fluorescent member is injected onto the light emitting element 10 in the concave portion of the molded body 40, filled in the concave portion, and further heated at 150 ° C. for 3 hours to cure the composition for the fluorescent member, and the fluorescent member 50 is formed. It was formed and a light emitting device 100 as shown in FIG. 1 was manufactured.

Average particle size D
For the aluminate phosphors according to each Example and Comparative Example, using Fisher Sub-Sieve Sizer Model 95 (manufactured by Fisher Scientific), an aluminate of 1 cm ³ minutes in an environment of a temperature of 25 ° C. and a humidity of 70% RH. The acid salt phosphor was measured as a sample, packed in a dedicated tubular container, dried air at a constant pressure was flowed, the specific surface area was read from the differential pressure, and a value converted into an average particle size D by the FSSS method was obtained. The results are shown in Tables 1 and 2.

Volume average particle size D50
For the aluminate phosphors according to each example and comparative example, the volume accumulation frequency from the small diameter side was increased by using a laser diffraction type particle size distribution measuring device (MASTER SIZEr 3000 manufactured by MAVERN). The volume average particle size D50 reaching 50% was measured. The results are shown in Tables 1 and 2.

Evaluation of Emission Characteristics Emission Spectrum The emission characteristics of the aluminate fluorophore according to each Example and Comparative Example were measured. Using a quantum efficiency measuring device (QE-2000, manufactured by Otsuka Electronics Co., Ltd.), each phosphor was irradiated with light having an excitation wavelength of 450 nm, and the emission spectrum at room temperature (25 ° C. ± 5 ° C.) was measured. FIG. 2 is an emission spectrum of the relative emission intensity (%) with respect to the wavelengths of the aluminate phosphor according to Reference Example 1, the aluminate phosphor according to Comparative Example 1, and the aluminate phosphor according to Comparative Example 2. ..

Relative emission intensity (%)
The relative emission intensity was calculated from the measured emission spectra of the aluminate phosphors according to each Example and Comparative Example, with the emission intensity at the emission peak wavelength of the aluminate phosphor according to Comparative Example 1 as 100%. The results are shown in Tables 1 and 2.

Reflectance (%)
Calcium hydrogen phosphate (CaHPO) at room temperature (25 ° C ± 5 ° C) using a spectrofluorometer (Hitachi High-Technologies Corporation, F-4500) for the aluminate phosphors according to each Example and Comparative Example. The reflection spectrum was measured using ₄ ) as a reference sample. In the reflection spectrum, the intensity of the reflected light of the reference sample at each wavelength was set to 100%, and the relative intensity of each phosphor at each wavelength was expressed as the reflectance (%). FIG. 3 is a reflection spectrum of the aluminate phosphor according to Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3, respectively. Table 1 shows the reflectance (%) at 450 nm, which is the excitation wavelength, and the reflectance (%) at 520 nm, which is near the emission peak wavelength of the aluminate phosphor, for the aluminate phosphors according to each Example and Comparative Example. And shown in Table 2.

SEM Photographs Using a scanning electron microscope (SEM), SEM photographs of the aluminate phosphor according to the examples and the aluminate phosphor according to the comparative example were obtained. FIG. 4 is an SEM photograph of the aluminate phosphor according to Reference Example 1, and FIG. 5 is an SEM photograph of the aluminate phosphor according to Comparative Example 1.

As shown in Table 1, the aluminate phosphors according to Reference Example 1 and Examples 2 to 4 have a lower reflectance at 450 nm than the aluminate fluorophore of Comparative Example 1, and absorb the excitation light in the blue region. Increased and the relative emission intensity increased. The aluminate phosphors according to Reference Example 1 and Examples 2 to 4 contain both Eu and Mn, and when excited by light in the blue region due to co-activation of Eu and Mn, the light is absorbed by Eu. Is increased, and the excitation energy is efficiently transferred from Eu to Mn, and it is presumed that the relative emission intensity is increased.
Further, as shown in Table 1, the aluminate phosphors according to Reference Example 1 and Examples 2 to 4 have a reflectance of 92% or more in the vicinity of the emission peak wavelength of 520 nm, and self-absorption is small.

On the other hand, since the aluminate phosphor according to Comparative Example 2 does not contain Eu, Eu does not absorb light in the blue region, and the relative emission intensities are the aluminates of Reference Example 1 and Examples 2 to 4. It was not as high as the phosphor.
Further, the aluminate phosphors according to Comparative Examples 3 and 4 have a variable t representing the molar ratio of Eu in the above formula (I) of 0.3 or more and have a low reflectance at 450 nm, so that they absorb in the blue region. Although the amount increased, the total amount of Eu and Mn as activators was large, and the relative emission intensity decreased due to the concentration quenching.

Further, the aluminate phosphor according to Comparative Example 5 has a large variable t representing the molar ratio of Eu in the above formula (I) exceeding 0.3, has a relatively high reflectance at 450 nm, and is excitation light. It is presumed that the relative emission intensity decreased because the absorption amount at 450 nm decreased. Further, in the aluminate phosphor according to Comparative Example 6, the variable t representing the molar ratio of Eu in the above formula (I) is larger than 0.3, and the variable r representing the molar ratio of Mn is 0.4. It is presumed that the light absorption by Eu and the transfer of the excitation energy from Eu to Mn were not efficiently performed, and the emission intensity was lowered.
In Comparative Examples 4 and 6, the reflectance in the vicinity of the emission peak wavelength of 520 nm is smaller than 92%, and it is presumed that the self-absorption by the aluminate phosphor itself is large.

As shown in FIG. 2, the peak wavelength of the emission spectrum of the aluminate phosphor according to Reference Example 1 has not changed as compared with the peak wavelength of the emission spectrum of the aluminate phosphor according to Comparative Example 1. It was confirmed that the aluminate phosphor according to Reference Example 1 had a higher relative emission intensity than the aluminate phosphor according to Comparative Examples 1 and 2.

As shown in FIG. 3, the aluminate phosphor according to Example 3 has a lower reflectance than the aluminate phosphor according to Comparative Example 1 in the wavelength range of 430 nm or more and 485 nm or less, and light from an excitation light source. Was confirmed to be absorbed efficiently. Further, as shown in FIG. 3, the aluminate phosphor according to Example 3 has the same reflectance at the emission peak wavelength of 520 nm as that of Comparative Example 2.
On the other hand, as shown in FIG. 3, the aluminate phosphor according to Comparative Example 3 has a reflectance lower than that of the aluminate phosphor according to Comparative Example 1 in the wavelength range of 430 nm or more and 485 nm or less, but has a reflectance of 520 nm. The reflectance at the emission peak wavelength was lower than that of the aluminate phosphor according to Example 3.

As shown in the SEM photographs of FIGS. 4 and 5, the aluminate phosphor according to Reference Example 1 and the aluminate phosphor according to Comparative Example 1 show a hexagonal crystal structure, and at least one surface is hexagonal. No significant difference in particle shape was confirmed between the aluminate phosphor according to Reference Example 1 and the aluminate phosphor according to Comparative Example 1.

As shown in Table 2, the aluminate phosphors according to Reference Examples 5 to 10 had a lower reflectance at 450 nm than the aluminate phosphors of Comparative Example 7, and the absorption of excitation light in the blue region was increased. As shown in Table 2, the aluminate phosphors according to Reference Examples 5 to 10 have increased absorption of excitation light in the blue region emitted by the light emitting device, and can efficiently perform wavelength conversion. Therefore, the amount of the phosphor contained in the fluorescent member is small, and the light emitting device can be miniaturized.

The light emitting device using the aluminate phosphor according to one embodiment of the present invention can be used in a wide range of fields such as general lighting, vehicle-mounted lighting, displays, liquid crystal backlights, traffic lights, and illuminated switches.

10: light emitting element, 40: molded body, 50: fluorescent member, 71: first fluorescent body, 72: second fluorescent body, 100: light emitting device.

Claims (4)

The average particle size D measured by the FSSS method is 11.2 μm or more and 12.0 μm or less, and the volume accumulation frequency from the small diameter side in the volume-based particle size distribution by the laser diffraction type particle size distribution measurement method reaches 50%. The particle size D50 is 17.3 μm or more and 17.7 μm or less, and the difference between the value of the average particle size D and the value of the volume average particle size D50 is 6.1 μm or less, which is represented by the following formula (I). An aluminate phosphor having a composition to be excited by an excitation light having an emission peak diameter in the range of 445 nm or more and 470 nm or less.
Ba _p Eu _t Mg _0.5 Mn _0.5 Al ₁₀ O ₁₇ (I)
(In the formula (I), p and t are numbers satisfying 0.900 ≦ p ≦ 0.970, 0.030 ≦ t ≦ 0.100, and p + t = 1.) A light emitting device including a fluorescent member containing the aluminate phosphor according to claim 1 and an excitation light source which is a light emitting element having a light emitting peak wavelength in the range of 445 nm or more and 470 nm or less. The fluorescent member includes a first phosphor containing the aluminate phosphor, a second fluorescent substance having an emission peak wavelength different from that of the first fluorescent substance, and a resin.
The light emitting device according to claim 2, wherein the second fluorescent substance contains at least one red fluorescent substance selected from the group consisting of an Mn-activated fluoride fluorescent substance and an Eu-activated nitride fluorescent substance. In the resin composition for a fluorescent member constituting the fluorescent member, the amount of the fluorescent substance containing the first fluorescent substance and the second fluorescent substance is 10 parts by mass or more and 115.1 parts by mass with respect to 100 parts by mass of the resin. The light emitting device according to claim 3, which is not more than parts by mass.

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