KR20090006790A - Light emitting device - Google Patents

Abstract

A light emitting device is provided to output a white light having high color rendering or the other color with high power by using fluorescent substance which is excited by the ultraviolet ray or the short wavelength visible light and radiates. In a light emitting device(1), a pair of electrodes(3a,3b) are formed on the substrate(2). A fluorescent layer(7) including the more than one class fluorescent substance radiating the visible light is formed on the light emitting device. One class or plural classes fluorescent substance has light-emitting property different with the first fluorescent substance and second fluorescent substance In the fluorescent layer.

Description

Light emitting device {LIGHT EMITTING DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device using phosphors, and more particularly to a high color rendering and high luminous device using phosphors which are excited and emitted with ultraviolet light or short wavelength visible light.

Various light emitting devices are known which are configured to obtain light of a desired color by combining a light emitting element and a phosphor which is excited by light generated by the light emitting element and generates light having a wavelength range different from that of the light emitting element.

In particular, as a white light emitting device having a long life and low power consumption, white light is obtained by combining semiconductor light emitting elements such as light emitting diodes (LEDs) and laser diodes (LDs), which emit ultraviolet or short wavelength visible light, and phosphors having these as excitation light sources. Attention has been paid to a light emitting device configured to obtain.

As a specific example of such a white light emitting device, (1) a combination of LEDs emitting blue light and phosphors excited by blue light to emit yellow light, (2) LEDs emitting violet or ultraviolet light, and purple Background Art A method of combining a plurality of phosphors which are excited by light or ultraviolet rays and emits light such as red, green, blue and yellow, respectively, is known.

[Patent Document 1] Japanese Patent No. 3503139

[Patent Document 2] Japanese Unexamined Patent Publication No. 2005-126577

[Patent Document 3] Japanese Unexamined Patent Publication No. 2003-110150

However, in the white light emitting device of the method (1), there is a problem that the light in the middle wavelength region of blue and yellow is hardly present and the color rendering is low because there is little light in the red region obtained from the phosphor. In addition, since white light is obtained by mixing the light of the LED and the phosphor, when the coating amount of the phosphor is changed in the manufacturing process of the white light emitting device, for example, the balance of the amount of light emitted by the LED and the phosphor is broken. There was a problem that fluctuations occurred.

On the other hand, although the white light emitting device of the method (2) has excellent color rendering property, no phosphor having a strong excitation band in the ultraviolet region or the short wavelength visible light region has been found, so that a high power white light emitting apparatus has been difficult to realize. For this reason, there is a strong demand for the development of a phosphor having a strong excitation band in the ultraviolet region or the short wavelength visible region and capable of efficiently emitting visible light. In particular, conventionally known indium-containing gallium nitride-based (InGaN-based) LEDs have good light emission characteristics in the wavelength region around 400 nm, and therefore are efficiently excited in the wavelength region around 400 nm, thereby providing visible light with high emission intensity. There has been a strong demand for the development of phosphors capable of emitting light.

Further, in order to realize a light emitting device having high color rendering property, development of a phosphor having a wide emission spectrum has been strongly demanded.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a high color rendering device and a high luminous flux using phosphors which are excited and emitted efficiently by ultraviolet or short wavelength visible light.

The present inventors, as a result of extensive studies to solve the above problems, the general formula _{^{M 1 O 2 · aM 2 O}} · bM 3 X 2: M 4 ( stage, M ¹ is as Si, Ge, Ti, Zr and Sn At least one element selected from the group consisting of, M ² is at least one element selected from the group consisting of Ca, Sr, Mg, Ba, and Zn, M ³ is a group consisting of Mg, Ca, Sr, Ba, and Zn At least one element selected from X, at least one halogen element, M ⁴ at least one element mandatory to Eu ²⁺ selected from the group consisting of rare earth elements and Mn. a? 1.3 and b ranges from 0.1? b? 0.25; newly discovered that ultraviolet or short wavelength visible light is efficiently excited in the wavelength region around 400 nm, thereby emitting visible light of high emission intensity. The present invention is completed by using this phosphor in a light emitting device. Groups reached.

That is, the light emitting device according to claim 1 of the present invention is a light emitting device including a light emitting element that emits ultraviolet light or short wavelength visible light and at least one phosphor that is excited by the ultraviolet light or short wavelength visible light to emit visible light. , The general formula is M ¹ O ₂ · aM ² O.bM ³ X ₂ : M ⁴ (wherein M ¹ is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, and M ² is Ca , At least one element selected from the group consisting of Sr, Mg, Ba and Zn, M ³ is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, X is at least 1 The halogen element of the species, M ⁴ , represents at least one element which is essentially essential for Eu ²⁺ selected from the group consisting of rare earth elements and Mn, where a is 0.1 ≦ a ≦ 1.3 and b is 0.1 ≦ b ≦ 0.25. To include a first phosphor, which is expressed as It shall be.

Further, the light emitting device according to claim 2 of the present invention includes a light emitting element emitting ultraviolet or short wavelength visible light, and at least two or more kinds of phosphors excited by the ultraviolet or short wavelength visible light to emit visible light, and the visible light emitted by each phosphor. In a light-emitting device having a complementary color relationship and configured to obtain white light by adding and mixing light from these phosphors, as the phosphor, a general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ⁴ (wherein M ¹ is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, M ² is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, M ³ is Mg, Ca, Sr, Ba, and at least one kind of element selected from the group consisting of Zn, X is a halogen atom of at least one kind, M ⁴ is that the Eu ^{2 +} is selected from the group consisting of rare earth elements and Mn are required At least one element, a being 0.1 ≦ a ≦ 1.3, b being in the range of 0.1 ≦ b ≦ 0.25), and visible light having a complementary relationship with visible light emitted by the first phosphor It characterized in that it comprises a second phosphor emitting.

In the first phosphor, when the content of M ⁴ in the general formula is c (molar ratio), the range of c is more preferably 0.03 <c / (a + c) <0.8.

In the first phosphor, M ¹ in the general formula is at least Si, the ratio of Si is 80 mol% or more, M ² in the general formula is at least Ca and / or Sr, The ratio of Ca and / or Sr is at least 60 mol%, M ³ of the general formula is at least Sr, Sr is at least 30 mol%, X of the general formula is at least Cl, and Cl It is more preferable that the ratio of is 50 mol% or more.

In the first phosphor, a in the general formula a is 0.3 ≦ a ≦ 1.2, b is 0.1 ≦ b ≦ 0.2, and the content c of M ⁴ is 0.05 ≦ c / (a + c) ≦ 0.5. It is more preferable.

Although the manufacturing method of the said 1st fluorescent substance is not specifically limited, The molar ratio of each of these compounds is represented by the composition formula of following (1)-(4) at least in a starting material, (1) :( 2) = 1: 0.1-1.0, (2) :( 3) = 1: 0.2-12.0, (2) :( 4) = 1: 0.05-4.0, Comprising: It can obtain by mixing and baking this starting material.

(1) M ¹ O ₂

(2) M ² O

(3) M ³ X ₂

(4) M ⁴

(Wherein M ¹ is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, and M ² is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn) , M ³ is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, X is at least one halogen element, M ⁴ is a rare earth element and Eu ²⁺ selected from the group consisting of Mn Represents at least one element that requires

In the starting material, M ¹ in the composition formula (1) is at least Si, the ratio of Si is at least 80 mol%, M ² in the composition formula (2) at least Ca and / or Sr and , Ca and / or Sr is at least 60 mol%, M ³ in the formula (3) is at least Sr, Sr is at least 30 mol%, and X in the formula is at least Cl It is essential that the ratio of Cl is 50 mol% or more.

In the starting materials, the molar ratio of each compound of the above formulas (1) to (4) is (1) :( 2) = 1: 0.25 to 1.0, (2) :( 3) = 1: 0.3 to 6.0, (2 ): (4) It is preferable to be weighed in the range of 0.05 to 3.0.

Furthermore, the molar ratio of each compound is (1) :( 2) = 1: 0.25-1.0, (2) :( 3) = 1: 0.3-4.0, (2) :( 4) = 1: 0.05-3.0 It is more preferable that it is the range of.

Further, in the starting material, it is preferable that the raw material of the composition formula (3) weighs an excess of stoichiometric ratio or more. This excess addition takes into account that part of the halogen element vaporizes and evaporates during firing of the raw material mixture, and can prevent the occurrence of crystal defects in the phosphor due to the lack of the halogen element.

In addition, this excess addition also acts as a flux and contributes to reaction promotion and crystallinity improvement.

In addition, although the measurement result of the X-ray diffraction in the said 1st fluorescent substance is not specifically limited, At least a part of the crystal | crystallization contained in a 1st fluorescent substance is a diffraction angle 2 (theta) in the X-ray diffraction pattern using the K-characteristic X-ray of Cu. When the diffraction intensity of the highest intensity diffraction peak existing in the range of 29.0 ° to 30.5 ° is set to 100, a diffraction peak having a diffraction intensity of 50 or more is present in the range of 28.0 ° to 29.5 °. A peak having a diffraction intensity of 8 or more exists in a range of diffraction angle 2θ of 19.0 ° or more and 22.0 ° or less, and a peak having a diffraction intensity of 15 or more exists in a range of diffraction angle 2θ of 25.0 ° or more and 28.0 ° or less. In the range where the diffraction angle 2θ is 34.5 ° or more and 37.5 ° or less, a peak having a diffraction intensity of 15 or more exists, and the diffraction angle 2θ is greater than or equal to 40.0 ° and 42.5 °, and the diffraction intensity is 10 or more. It is preferable that it is fluorescent substance in which the peak which shows diffraction intensity 10 or more exists in the range of 13.0 degrees or more and 15.0 degrees or less.

In addition, although the measurement result of the X-ray diffraction in the said 1st fluorescent substance is not specifically limited, At least a part of the crystal | crystallization contained in a 1st fluorescent substance has the diffraction angle 2 (theta) 12.5 in the diffraction pattern using Mo Kα characteristic X-rays. When the diffraction intensity of the highest intensity diffraction peak present in the range of not less than 1 ° and not more than 15.0 ° is set to 100, a diffraction peak having a diffraction intensity of 50 or more exists in the range of 12.0 ° or more and 14.5 ° or less. And a peak having a diffraction intensity of 8 or more exists in a range where the diffraction angle 2θ is 8.0 ° or more and 10.5 ° or less, and a peak having a diffraction intensity 15 or more exists in a range where the diffraction angle 2θ is 11.0 ° or more and 13.0 ° or less, A peak having a diffraction intensity of 15 or more exists in a range in which each 2θ is 15.5 ° or more and 17.0 ° or less, and a diffraction angle 2θ is 10 or more in a range of 17.5 ° or more and 19.5 ° or less, and the diffraction angle 2θ is 5. It is preferable that the peak which shows diffraction intensity 10 or more exists in the range of 0 degrees or more and 8.0 degrees or less.

In addition, although the crystal structure in the said 1st fluorescent substance is not specifically limited, It is preferable that at least one part of the crystal | crystallization contained in a 1st fluorescent substance is a crystal containing a fluorescence-type crystal structure.

In addition, it is preferable that at least a part of the crystals included in the first phosphor are crystals belonging to a crystal system: monoclinic, Brave lattice: low-core monoclinic lattice, and a space group: C2 / m.

In addition, in order to obtain higher emission intensity in the first phosphor, it is preferable that the amount of the crystal contained in the phosphor is as much as possible, preferably in a single phase, and the content of the crystal is 20% by mass or more. desirable. More preferably, the emission intensity is significantly improved at 50 mass% or more.

In addition, it can be composed of a mixture with other crystalline phases or amorphous phases in the range that the properties are not deteriorated, and in particular, excessive addition of SiO ₂ in the mixing ratio of the starting materials, quartz, tridimite, cristobalite which is a crystal composed of SiO ₂ In the phosphor synthesized as a slight by-product, the luminescence intensity may be improved in some cases.

The light emitting device according to the present invention uses a light emitting element that emits ultraviolet rays or short wavelength visible light as the excitation light source. For this reason, it is preferable that the said 1st fluorescent substance has a strong excitation band in the wavelength range of 350 nm-430 nm from a viewpoint of luminous efficiency, light emission brightness, etc. of a light emitting device.

In addition, from the viewpoint of the color rendering of the light emitting device, it is preferable that the emission spectrum of the first phosphor is in the wavelength range of 560 nm to 590 nm, and the half width is 100 nm or more.

The second phosphor is not particularly limited as long as the second phosphor emits visible light having a complementary color with visible light emitted by the first phosphor. However, the first phosphor is mainly yellow based for the purpose of obtaining a white light emitting device. Since it emits light, it is preferable to use the fluorescent substance which emits blue light which is the complementary light.

For the same purpose, it is preferable that the emission spectrum of the second phosphor is in the wavelength range of 440 nm to 470 nm and the half width is 30 nm to 60 nm from the color rendering point.

As an example of this second preferred phosphor, the general formula Ca _xyz Mg _y (PO ₄ ) ₃ Cl: EU ²⁺ _z (where x is 4.95 <x <5.50, y is 0 <y <1.50, z is 0.02 <z) And phosphors represented by a range of <0.20, and y + z is in a range of 0.02 ≦ y + z ≦ 1.7.

The light emitting element is not particularly limited as long as it emits at least ultraviolet light or short wavelength visible light, but it is preferable that the peak of the light emission spectrum is in the wavelength range of 350 nm to 430 nm in view of the light emission efficiency of the light emitting device. .

Moreover, as a specific example of the said light emitting element, various light sources, such as semiconductor light emitting elements, such as LED and LD, the light source for obtaining light emission from vacuum discharge or thermal light emission, an electron beam excitation light emitting element, etc. can be used.

Here, by using a semiconductor light emitting element as the light emitting element, it is possible to obtain a light emitting device that is compact in size and saves power and has a long lifetime.

Suitable examples of such semiconductor light emitting devices include InGaN-based LEDs and LDs having good light emission characteristics in the wavelength region around 400 nm.

By constructing a light emitting device as described above, a light emitting device capable of emitting light having high color rendering property or light of another color with high output can be obtained.

EMBODIMENT OF THE INVENTION Hereinafter, although embodiment of this invention is described using drawing, this invention is not restrict | limited by the following examples etc. at all.

1 is a schematic cross-sectional view showing a first embodiment of a light emitting device of the present invention.

In the light emitting device 1 shown in FIG. 1, a pair of electrodes 3a (anode) and 3b (cathode) are formed on the substrate 2. The semiconductor light emitting element 4 is fixed on the electrode 3a by the mounting member 5. The semiconductor light emitting element 4 and the electrode 3a are energized by the mounting member 5, and the semiconductor light emitting element 4 and the electrode 3b are energized by the wire 6. The fluorescent layer 7 is formed on the semiconductor light emitting element.

The substrate 2 is preferably formed of a material having no thermal conductivity but high conductivity. For example, a ceramic substrate (aluminum nitride substrate, an alumina substrate, a mullite substrate, a glass ceramic substrate) or a glass epoxy substrate can be used. .

The electrodes 3a and 3b are conductive layers formed of metal materials such as gold and copper.

The semiconductor light emitting element 4 is an example of a light emitting element used in the light emitting device of the present invention. For example, an LED, LD or the like that emits ultraviolet rays or short wavelength visible light may be used. Specific examples thereof include an InGaN compound semiconductor. In the InGaN compound semiconductor, the emission wavelength range changes depending on the content of In. When the content of In is large, the emission wavelength tends to be long, and when it is small, the emission wavelength tends to be short. However, the InGaN compound semiconductor containing In has the highest quantum efficiency in light emission to the extent that the peak wavelength is around 400 nm. It is confirmed.

The mounting member 5 is, for example, a conductive adhesive such as silver paste, or a gold tin eutectic solder. The lower surface of the semiconductor light emitting element 4 is fixed to the electrode 3a, and the lower surface side electrode and the substrate 2 of the semiconductor light emitting element 4 are fixed. The electrode 3a on the () is electrically connected.

The wire 6 is a conductive member such as a gold wire, and is bonded to the upper surface side electrode and the electrode 3b of the semiconductor light emitting element 4 by, for example, ultrasonic thermocompression or the like, and electrically connects both.

The fluorescent layer 7 is sealed in the form of a film covering the upper surface of the semiconductor light emitting element 4 with a first phosphor, or the first phosphor and the second phosphor, which will be described later, by a binder member. The fluorescent layer 7 is formed of, for example, a phosphor paste in which phosphors are mixed into a liquid or gel binder member, and then the phosphor paste is applied to the upper surface of the semiconductor light emitting element 4, after which a binder of the phosphor paste is applied. It can form by hardening a member.

As the binder member, for example, a silicone resin or a fluororesin can be used. In particular, since the light emitting device of the present invention uses ultraviolet rays or short wavelength visible light as the excitation light source, a binder member having excellent ultraviolet resistance performance is preferable.

The fluorescent layer 7 may contain one or more kinds of phosphors having different light emission characteristics from the first phosphor and the second phosphor. Thereby, light of various colors can be obtained by synthesize | combining the light of various wavelength ranges.

In addition, the fluorescent layer 7 may be mixed with materials other than phosphors having various physical properties. For example, the refractive index of the fluorescent layer 7 can be increased by incorporating a substance having a higher refractive index than the binder member such as a metal oxide, a fluorine compound, or a sulfide into the fluorescent layer 7. Thereby, the effect that the total reflection which generate | occur | produces when the light emitted from the semiconductor light emitting element 4 is incident on the fluorescent layer 7 can be reduced, and the acquisition efficiency of the excitation light to the fluorescent layer 7 can be obtained. In addition, by making the particle diameter of the material to be mixed into the nano-size, the refractive index can be increased without lowering the transparency of the fluorescent layer 7. In addition, white powder having an average particle diameter of about 0.3 µm to 3 µm, such as alumina, zirconia, titanium oxide, or the like, may be incorporated into the phosphor layer 7 as a light scattering agent. Thereby, nonuniformity in brightness | luminance and chromaticity in a light emitting surface can be prevented.

2 is a schematic cross-sectional view showing a second embodiment of the light emitting device of the present invention.

This second embodiment is a semiconductor light emitting device called a can package type. In the second embodiment, the fluorescent layer 7 is formed on the surface of the semiconductor light emitting element 4 in the first embodiment. The fluorescent layer 7 and the semiconductor light emitting element 4 are spaced apart from each other.

In addition, about the part same as the component of 1st Embodiment shown in FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

In the light emitting device 1 shown in FIG. 2, an inert gas is sealed in a sealed space formed of the metal stem 8 and the can cap 9, and the semiconductor light emitting element 4 is formed of a metal stem ( 8) is housed in a form that is fixed through the substrate (2). The ceramic block 13 is fitted into the opening of the metal stem 8 and fixed. The pair of electrode terminals 10a (anode) and 10b (cathode) extend through the ceramic block 13 into and out of the sealed space, and the electrode terminals 10a and 10b and the semiconductor light emitting element 4 Each is energized by the wire 6. An opening 11 is formed in the center of the upper surface of the can cap 9, and the transparent plate 12 is sealed as if the opening 11 is closed from the inner surface side of the can cap 9. The fluorescent layer 7 is formed in the opening 11.

The metal stem 8 and the can cap 9 are joined to each other by welding or the like to form a sealed space.

The metal stem 8 and the can cap are preferably made of the same material. For example, various metals and alloys such as cobalt and copper-tungsten may be used. Since the metal stem 8 supports the semiconductor light emitting element 4 in the sealed space and also serves to release heat generated by the semiconductor light emitting element 4 out of the sealed space, a material having a high thermal conductivity is preferable.

The inert gas enclosed in the sealed space is at least one kind of inert gas selected from, for example, nitrogen, helium, argon, and the like, whereby deterioration of the semiconductor light emitting element 4 can be suppressed.

The ceramic block 13 is, for example, a non-conductive member such as alumina, aluminum nitride, and is fitted into and fixed to an opening formed in the metal stem 8, and electrically insulates the electrode terminals 10a and 10b from the metal stem 8. Keeping up.

The semiconductor light emitting element 4 is fixed to the substrate using solder or the like, and the substrate 2 is fixed to the metal stem using solder or the like.

The electrode terminals 10a and 10b are metal conductive members, and are obtained by, for example, punching of a metal flat plate.

The transparent plate 12 is a plate-shaped member formed of a light-transmissive material such as glass, resin, or the like, and may be formed in a convex or concave shape as necessary to give a lens effect.

The fluorescent layer 7 is formed on the surface of the transparent plate at the opening 11, and the formation method thereof is the same as in the first embodiment.

3 is a schematic cross-sectional view showing the third embodiment of the light emitting device of the present invention.

In addition, about the same part as the component of 1st Embodiment shown in FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

In the light emitting device 1 shown in FIG. 3, an electrode terminal 10a (anode) is provided at the bottom of the cup-shaped container 13, and an electrode terminal 10b (cathode) is provided at the side of the container, respectively. have.

The semiconductor light emitting element 4 is mounted on the upper surface of the electrode terminal 10a via the mounting member 5 at the bottom of the container 13. The lower surface electrode and the electrode terminal 10a of the semiconductor light emitting element 4 are electrically connected by the mounting member, and the upper electrode and the electrode terminal 10b of the semiconductor light emitting element 4 are electrically connected by the wire 6. It is.

The filling member 14 is filled in the inner space of the container 13 so as to cover the semiconductor light emitting element 4, and the upper surface of the container 13 is sealed by the transparent plate 12. The fluorescent layer 7 is formed on the container side of the transparent plate 12.

The container 13 is made of a resin such as polyphthalamide, aromatic nylon, polysulfone, polyamideimide, liquid crystal polymer, polycarbonate, or the like, and may be molded integrally with the electrode terminals 10a and 10b by insert molding or the like.

The inner space of the container 13 is formed in the opening so that the diameter may become large from the bottom to the upper portion, and may be configured to reflect the light from the semiconductor light emitting element 4 by reflecting the opening inside. have.

The filling member 14 is, for example, a transparent resin such as silicone resin or fluorine resin, and preferably exhibits good light resistance.

The fluorescent layer 7 is formed in the container inner side surface of a transparent plate by the formation method similar to 1st Embodiment.

In the light emitting device configured as described above, when a driving current is applied to the electrodes 3a and 3b or the electrode terminals 10a and 10b, the semiconductor light emitting element 4 is energized, and the semiconductor light emitting element 4 is the fluorescent layer 7. Irradiate light in an inherent wavelength range including ultraviolet light or short wavelength visible light. By this light, the phosphor in the fluorescent layer 7 is excited, and the phosphor irradiates light in a unique wavelength range. By using such a structure, various selections of the semiconductor light emitting element 4 and / or the phosphor can be made a light emitting device for irradiating desired light.

Next, the first phosphor and the second phosphor used in the light emitting device of the present invention will be described in detail.

The first phosphor can be obtained, for example, as follows.

As a 1st fluorescent substance, the compound represented by the composition formula of following (1)-(4) can be used as a raw material.

(1) M ¹ O ₂ (M ¹ represents tetravalent elements such as Si, Ge, Ti, Zr, Sn.)

(2) M ² O (M ² represents a divalent element such as Mg, Ca, Sr, Ba, Zn.)

(3) M ³ X ₂ (M ³ represents a divalent element such as Mg, Ca, Sr, Ba, Zn, and X represents a halogen element.)

(4) M ⁴ (M ⁴ represents rare earth elements such as Eu ²⁺ and / or Mn.)

As a raw material of the composition formula (1), SiO ₂ , GeO ₂ , TiO ₂ , ZrO ₂ , SnO _2, or the like can be used.

As a raw material of the composition formula (2), for example, carbonates, oxides, hydroxides and the like of divalent metal ions can be used.

As a raw material of the composition formula (3), for example, SrCl ₂ , SrCl ₂ · 6H ₂ O, MgCl ₂ , MgCl ₂ · 6H ₂ O, CaCl ₂ , CaCl ₂ · 2H ₂ O, BaCl ₂ , BaCl ₂ · 2H ₂ O, use the _{ZnCl 2, MgF 2, CaF 2} , SrF 2, BaF 2, ZnF 2, MgBr 2, CaBr 2, SrBr 2, BaBr 2, ZnBr 2, MgI 2, CaI 2, SrI 2, BaI 2, ZnI 2 , etc. Can be.

As a raw material of the composition formula (4), for example, Eu ₂ O ₃ , Eu ₂ (CO ₃ ) ₃ , Eu (OH) ₃ , EuCl ₃ , MnO, Mn (OH) ₂ , MnCO ₃ , MnCl ₂ .4H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O and the like can be used.

As a raw material of the composition formula of said (1), M1 is at least ^{1 type} of at least Si, and it is at least 1 sort (s) of element chosen from the group which consists of Si, Ge, Ti, Zr, and Sn, and the ratio of Si is 80 mol% or more. Compound is preferred.

As a raw material of the composition formula of the above (2), at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, at least M ² is essentially Ca and / or Sr, and Ca and / or Preference is given to compounds in which the proportion of Sr is at least 60 mol%.

As a raw material of the composition formula of (3), M ³ is at least one element selected from the group consisting of at least Sr, Mg, Ca, Sr, Mg, Ba, and Zn, and Sr is 30 mol% or more. A compound is preferable, and X is at least 1 type of halogen element which makes at least Cl essential, and the compound whose ratio of Cl is 50 mol% or more is preferable.

As a raw material of the composition formula of said (4), it is preferable that M <^4> is a rare earth element which makes bivalent Eu essential, and may contain rare earth elements other than Mn or Eu.

The molar ratio of the raw material of the composition formula of said (1)-(4) is (1) :( 2) = 1: 0.1-1.0, (2) :( 3) = 1: 0.2-12.0, (2) :( 4 ) = 1: 0.05 to 4.0, preferably (1) :( 2) = 1: 0.25 to 1.0, (2) :( 3) = 1: 0.3 to 6.0, (2) :( 4) = 1: 0.05 -3.0, More preferably, the ratio (1) :( 2) = 1: 0.25-1.0, (2) :( 3) = 1: 0.3-4.0, (2) :( 4) = 1: 0.05-3.0 Weighed and each weighed raw material is put in alumina trigger and pulverized and mixed for about 30 minutes to obtain a raw material mixture. This raw material mixture is placed in an alumina crucible and calcined for 3 to 40 hours at (H ₂ / N ₂ ), temperature 700 ° C. or higher and lower than 1100 ° C. in an atmosphere (5/95) in an electric furnace in a reducing atmosphere to obtain a fired product. The phosphor of the present invention can be obtained by washing the calcined product well with warm pure water and washing off any excess chloride.

In particular, it is preferable that the raw material (bivalent metal halide) of the composition formula (3) measures the excess amount more than stoichiometric ratio. This is to consider that part of the halogen element vaporizes and evaporates during firing, and is to prevent the occurrence of crystal defects in the phosphor due to the lack of the halogen element. In addition, the excessively added raw material (3) liquefies at the firing temperature, acts as a flux of the solid phase reaction, and exhibits an action of promoting the solid phase reaction and improving crystallinity.

Further, after firing of the raw material mixture, the raw material of the composition formula of the excessively added (3) is present as an impurity in the produced phosphor. Therefore, in order to obtain phosphors having high purity and high luminescence intensity, these impurities must be washed with warm pure water.

The composition ratio shown in the general formula of the phosphor of the present invention is the composition ratio after washing out the impurities, and the raw material of the composition formula (3), which is excessively added and becomes impurities as described above, is not added in this composition ratio.

In order to obtain a phosphor having high luminous efficiency from the phosphor of the present invention, it is preferable to use very few metal elements as impurities. In particular, transition metal elements such as Fe, Co, and Ni act as deactivators of luminescence, and therefore, it is necessary to prevent the use of high purity raw materials and the incorporation of impurities in the synthesis process so that the sum of these elements is 500 ppm or less. desirable.

<Specification of Crystal Structure of First Phosphor>

Crystals, such as the crystal structure of the 1st fluorescent substance in this invention, grew the single crystal of the parent crystal mentioned below, and were performed based on the analysis result.

This parent crystal is M ¹ = Si, M ² = Ca and Sr, M ³ = Sr, and X = Cl in the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ , M ⁴ is a substance which does not contain.

Generation and analysis of parent crystals

Crystal growth of the single crystal of the mother crystal was performed in the following procedure.

First, each raw material of SiO ₂ , CaO, SrCl ₂ was weighed such that the molar ratio thereof was SiO ₂ : CaO: SrCl ₂ = 1: 0.71: 1.07, and each weighed raw material was put into alumina-induced powder and mixed for about 30 minutes. A raw mixture was obtained. The raw material mixture was charged into a tablet to uniaxially compression molding at 100 MPa to obtain a molded body. The molded product was placed in an alumina crucible and covered with a lid, and then fired at 1030 ° C. for 36 hours in the air to obtain a fired product. The resulting fired product was washed with warm pure water and ultrasonic waves to obtain a parent crystal.

Thus, a single crystal having a diameter of 0.2 mm was obtained in the parent crystal produced.

About the obtained mother crystal, elemental quantitative analysis was performed by the following method, and the composition ratio (value of a, b in the said general formula) was determined.

1. Quantitative Analysis of Si

The mother crystal was melted in a platinum crucible with sodium carbonate, and then dissolved and dissolved in rare acid to obtain a constant volume. About this solution, the amount of Si was measured using the ICP emission spectroscopy apparatus (SII nanotechnology company make: SPS-4000).

2. Quantitative Analysis of Metal Elements

The parent crystal was thermally decomposed with perchloric acid, nitric acid, and hydrofluoric acid under inert gas, dissolved in rare acid, and used for dialysis. About this solution, the amount of metal elements was measured using the ICP emission spectrophotometer (SII-Nano Technology Co., Ltd. product: SPS-4000).

3. Quantitative Analysis of Cl

The parent crystal was burned in a tubular electric furnace, and the generated gas was adsorbed to the adsorption liquid. About this solution, Cl amount was determined by the ion chromatograph method using DX-500 by Dionex.

4. Quantitative Analysis of O

The mother crystal was thermally decomposed in argon using a nitrogen oxygen analyzer TC-436 manufactured by LECO Corporation, and the generated oxygen was quantified by infrared absorption method.

The approximate composition ratio of the parent crystal obtained as a result of the above elemental quantitative analysis is as follows.

SiO ₂ .1.05 (Ca _0.6 , Sr _0.4 ) O.0.15 SrCl ₂

In addition, the specific gravity of the said matrix crystal measured by the picnometer was 3.4.

Regarding the single crystal of the mother crystal, an X-ray diffraction pattern using K α-ray (wavelength λ = 0.71 Hz) of Mo was measured by an imaging plate single crystal automatic X-ray structure analyzer (R-AXIS RAPID, manufactured by RIGAKU Co., Ltd.) Hereinafter, measurement 1 is called).

An example of the X-ray diffraction photograph obtained by this measurement 1 is shown in FIG.

By the measurement 1, the following crystal structures were analyzed using 5709 diffraction spots obtained in the range of 2θ <60 ° (d> 0.71 Hz).

About the parent crystal, the crystal system, the Brava lattice, the space group, and the lattice constant of the mother crystal were determined from the X-ray diffraction pattern according to Measurement 1 using data processing software (Rigoku, Rapid Auto).

Crystalline: Monoclinic

Brave Lattice: Low-core Single Lattice

Space group: C2 / m

Grid Constant:

a = 13.3036 (12)

b = 8.3067 (8)

c = 9.1567 (12)

α = γ = 90˚

β = 110.226 (5) ˚

V = 949.50 (18) Å ³

Thereafter, the rough structure was determined by a direct method using crystal structure analysis software (Crystal Stracture, manufactured by RIGAKU Co., Ltd.), and then the structural parameters (spot occupancy, atomic coordinates, temperature factor, etc.) were refined by the least square method. .

The refinement is carried out for an independent 1160 point F | where | F |> 2σ _F , and as a result, a crystal structure model of reliability factor R ₁ = 2.7% is obtained.

This crystal structure model is hereinafter referred to as "initial structure model".

Table 1 shows the atomic coordinates and the occupancy ratio of the initial structural model obtained from the single crystal.

TABLE 1

Table 1. Atomic Coordinates and Shares of Initial Structural Models Obtained from Single Crystals

The composition ratio of the initial structural model determined from the single crystal was calculated as follows.

SiO ₂ · 1.0 (Ca _0.6 , Sr _0.4 ) O.0.17SrCl ₂

As a result of the analysis, the parent crystal was found to be a crystal of a novel structure that is not registered in the International Center for Diffraction Data (ICDD), which is an X-ray diffraction database widely used for X-ray diffraction.

Next, the parent crystal of the powder which is a form equivalent to a fluorescent substance was adjusted, and it checked whether it was a crystal structure belonging to an initial structural model.

The powder matrix crystal was adjusted in the following procedure. First, SiO _2, that their molar ratio of the respective raw materials of _{CaO, SrO, SrCl 2 SiO 2} , CaO, SrO, SrCl 2 = 1.0: 0.7: 0.2: and weighed to 1.0, put the respective raw materials were weighed in an alumina induced about The mixture was ground for 30 minutes to obtain a raw material mixture. This raw material mixture was packed into a tablet shape and uniaxially compression molded at 100 MPa to obtain a molded body. The molded product was placed in an alumina crucible and covered with a lid, and then fired at 1030 ° C. for 5 to 40 hours to obtain a fired product. The calcined product was washed with warm pure water and ultrasonic waves to obtain powder matrix crystals.

Next, in order to obtain a detailed crystal structure of the powder matrix crystal, powder X-ray diffraction was measured using Mo Kα characteristic X-ray by a high-resolution powder X-ray diffractometer (manufactured by RIGAKU Co., Ltd.) of Nagoya University. , Called measurement 2).

About the result of the measurement 2, Rietveld analysis was performed and the crystal structure was specified. In carrying out the Rietveld analysis, the structural model was refined by the least square method using the lattice constant, atomic coordinates, and spatial group of the initial structural model as a model.

As a result, the diffraction pattern observed in Measurement 2 and the calculated diffraction pattern fitted by Rietveld analysis were in good agreement, and the R factor for determining the agreement scale showed a very small value of Rwp = 2.84%. This concluded that the mother crystal of the single crystal and the mother crystal of the powder were crystals of the same structure.

5 shows a fit diagram of Rietveld analysis for Measurement 2.

At the top of FIG. 5, the solid line is the powder X-ray diffraction pattern by calculation obtained by Rietveld analysis, and the cross plot shows the powder X-ray diffraction pattern observed by measurement 2.

The interruption of FIG. 5 shows the peak angle of diffraction by calculation obtained by Rietveld analysis.

The lower part of FIG. 5 plots the difference between the calculated value and the observed value of the powder X-ray diffraction pattern shown at the upper part, and it can be seen that there is almost no difference between the two and is in good agreement.

The lattice constant of the refined powder matrix crystal is shown below.

a = 13.2468 (4) Å, b = 8.3169 (2) Å, c = 9.1537 (3) Å

α = γ = 90 °, β = 110.251 (2) °

V = 946.1 (1) Å ³

Table 2 shows the atomic coordinates of the refined powder matrix crystals.

TABLE 2

Table 2. Atomic Coordinates and Shares Obtained from Powder Crystals

The theoretical composition ratio of the said powder matrix crystal | crystallization computed by the Rietveld analysis based on the measurement 2 is shown below.

<Theoretical Composition Ratio of Powder Matrix Crystal>

SiO ₂ · 1.0 (Ca _0.6 , Sr _0.4 ) O.0.17 SrCl ₂

The element which can form a solid solution in the said parent crystal is listed below.

Here, the solid solution means that the composition ratio of the elements constituting the parent crystal is varied or a part of the elements constituting the parent crystal is replaced with another element, and the mother crystal and the lattice constant have the same crystal structure.

<Group of elements that can be melted in the parent crystal>

Si substituted elements of SiO ₂ : Ge, Ti, Zr, and Sn

Ca and / or Sr substituted elements of (Ca _0.6 , Sr _0.4 ) O: Mg, Ba, Zn, Mn and rare earth elements

Sr Substitution Elements of SrCl ₂ : Mg, Ca, Ba, and Zn

Cl substitution elements for SrCl ₂ : F, Br, and I

In addition, a part of SiO ₂ composed of an oxide of a Group 4 element can be replaced with 1/2 (B, P) O ₄ , 1/2 (Al, P) O ₄ .

<Confirmation of Crystal Structure of First Phosphor>

Identification of the crystal structure of the solid solution can be determined by the identity of the diffraction result of X-ray diffraction or neutron diffraction, but the crystal in which part of the constituent element is replaced with another element capable of solid melting from the original crystal is lattice constant. Since is changed, even if the crystal belongs to the same crystal structure as the original crystal, the diffraction result is not completely the same.

In crystals belonging to the same crystal structure, when the lattice constant becomes smaller due to element substitution, the diffraction angle is shifted to the high angle side, and when the lattice constant is increased, the diffraction angle is shifted to the low angle side.

Thus, as Eu ^{2 +} (M ⁴ element in the general formula) the powder host crystals and, that the light emission of the fluorescent material around the portion of the (M ² element in the general formula) Ca and / or Sr constituting the host crystals It evaluated using the following determination method about whether the substituted 1st fluorescent substance (phosphor (1) mentioned later) belongs to the same crystal structure.

As a determination method for confirming the crystal structure, Rietveld analysis is performed using the result of X-ray diffraction (or neutron diffraction) of the determination object using the lattice constant, atomic coordinates, and space group of the initial crystal model as a model, and R By determining the factors, it is possible to determine whether they have the same structure.

Specifically, if the Rietveld analysis of the determination target converges to a low R factor at the same level as the Rietveld analysis of the powder mother crystal, it can be determined that the crystal of the same structure.

In addition, by comparing the lattice constants and atomic coordinates obtained by Rietveld analysis, it is possible to discuss the fine structure differences.

Since this determination method was used, first, the X-ray diffraction pattern was measured on the phosphor (the phosphor 1 described later) of the present invention under the same conditions as in the measurement 2 (hereinafter referred to as measurement 3).

On the basis of the obtained X-ray diffraction pattern, Rietveld analysis was performed using the initial structural model as a model. As a result, the R factor Rwp value of the criterion of determination was very small at 3.69%, and converged to a level equivalent to the Rwp value of the powder matrix crystal.

6 shows a fit diagram of Rietveld analysis for Measurement 3.

At the top of FIG. 6, the solid line is the powder X-ray diffraction pattern by calculation obtained by Rietveld analysis, and the cross plot shows the powder X-ray diffraction pattern observed by measurement 3.

The interruption of FIG. 6 shows the peak angle of diffraction by calculation obtained by Rietveld analysis.

The lower part of FIG. 6 plots the difference between the calculated value and the observed value of the powder X-ray diffraction pattern shown at the upper part, and it can be seen that there is almost no difference between the two.

As mentioned above, it is determined that a 1st fluorescent substance is the same crystal structure as the said parent crystal.

The second phosphor can be obtained, for example, as follows.

The second phosphor uses CaCO ₃ , MgCO ₃ , CaCl ₂ , CaHPO ₄ , and Eu ₂ O ₃ as raw materials, and the molar ratio of these raw materials is CaCO ₃ : MgCO ₃ : CaCl ₂ : CaHPO ₄ : Eu ₂ O ₃ = Weighing is carried out at a predetermined ratio so as to be 0.05 to 0.35: 0.01 to 0.50: 0.17 to 0.50: 1.00: 0.005 to 0.050, and each weighed raw material is put in alumina mortar to be pulverized and mixed for about 30 minutes to obtain a raw material mixture. The raw material mixture is placed in an alumina crucible and calcined at a temperature of 800 ° C. or higher and less than 1200 ° C. for 3 hours in an N ₂ atmosphere containing ₂ to 5% of H ₂ to obtain a fired product. The second phosphor can be obtained by washing the calcined product well with warm pure water and washing away any excess chloride.

It is also preferable that for the weighing (molar ratio) of CaCl ₂ when the gain of the second raw material mixture, weighed and an excess amount of 0.5 mol or more than the stoichiometric ratio with respect to the composition ratio of the second phosphor to be manufactured. This makes it possible to prevent occurrence of crystal defect of the second phosphor caused by a shortage of Cl _2.

EXAMPLE

Although the light emitting device configured as described above will be described in more detail with reference to the following examples, the following descriptions of raw materials, manufacturing methods, chemical compositions of phosphors, etc. of the light emitting device limit the embodiments of the light emitting device of the present invention. It is not at all.

First, the phosphor used in the light emitting device of this embodiment is described in detail.

<Phosphor 1>

SiO ₂ 0.9 (Ca _0.5 , Sr _0.5 ) O 0.17 SrCl ₂ : A phosphor represented by EU ^{2 +} _0.1 .

This phosphor 1 is an example of the first phosphor, and M ¹ = Si, M ² = Ca / Sr (molar ratio 50/50), M in general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ^{4 3 = Sr, X = Cl,} M 4 = Eu 2 +, a = 0.9, b = 0.17, is obtained by synthesizing the phosphor such that the content of M ⁴ c (mole ratio) is c / (a + c) = 0.1.

In the production of the phosphor 1, first, each of the raw materials of SiO ₂ , Ca (OH) ₂ , SrCl ₂ · 6H ₂ O, and Eu ₂ O ₃ has a molar ratio of SiO ₂ : Ca (OH) ₂ : SrCl ₂ · 6H ₂ O: Eu ₂ O ₃ = 1.0: 0.65: 1.0: 0.13, and the weighed raw materials were put in an alumina mortar to grind and mixed for about 30 minutes to obtain a raw material mixture. The raw material mixture was placed in an alumina crucible and calcined at 1030 ° C. for 5 to 40 hours in (H ₂ / N ₂ ) in an atmosphere (5/95) in an electric furnace in a reducing atmosphere to obtain a fired product. The obtained fired substance was wash | cleaned well with warm pure water, and this phosphor 1 was obtained.

<Phosphor 2>

SiO ₂ 0.9 (Ca _0.6 , Sr _0.4 ) O 0.17 SrCl ₂ : phosphor represented by EU ^{2 +} _0.1 .

This phosphor 2 is an example of the first phosphor, and M ¹ = Si, M ² = Ca / Sr (molar ratio 60/40), M in general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ^{4 3 = Sr, X = Cl,} M 4 = Eu 2 +, a = 0.9, b = 0.17, is obtained by synthesizing the phosphor such that the content of M ⁴ c (mole ratio) is c / (a + c) = 0.1.

In addition, the present phosphor 2 is a phosphor in which cristobalite is produced in the phosphor by excessively adding SiO ₂ in the mixing ratio of the raw materials.

In the production of the phosphor 2, first, each of the raw materials of SiO ₂ , Ca (OH) ₂ , SrCl ₂ · 6H ₂ O, and Eu ₂ O ₃ has a molar ratio of SiO ₂ : Ca (OH) ₂ : SrCl ₂ · 6H _{2 O: Eu 2 O 3 =} 1.1: 0.45: 1.0: 0.13 was weighed so that, then got a phosphor 2 in the same way as the first phosphor.

<Phosphor 3>

SiO ₂ · 0.86 (Ca _0.47 , Sr _0.52, Ba _0.01 ) O.0.17 SrCl ₂ : A phosphor represented by EU ²⁺ _0.14 .

This phosphor 3 is an example of the first phosphor, and M ¹ = Si, M ² = Ca / Sr / Ba (molar ratio 47/52 /) in the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ . 1) synthesis so that the ^{M 3 = Sr, X = Cl} , M 4 = Eu 2 +, a = 0.86, b = 0.17, surface c / (a + c) = 0.14 to prescribe the amount of the content c of M ⁴ One phosphor.

This phosphor 3 is a phosphor in which Ba is further added to Ca and Sr as M ² elements, and is a phosphor in which cristobalite is produced in the phosphor by excessive addition of SiO ₂ in the mixing ratio of the raw materials.

In the production of the phosphor 3, first, each of the raw materials of SiO ₂ , CaCO ₃ , BaCO ₃ , SrCl ₂ · 6H ₂ O and Eu ₂ O ₃ has a molar ratio of SiO ₂ : CaCO ₃ : BaCO ₃ : SrCl ₂ · 6H ₂ Phosphor 3 was weighed so that O: Eu ₂ O ₃ = 1.68: 0.45: 0.02: 1.0: 0.13, and then the present phosphor 3 was obtained in the same manner as the phosphor 1.

<Phosphor 4>

SiO ₂ 0.86 (Ca _0.49 , Sr _0.50, Mg _0.01 ) O 0.17 SrCl ₂ : A phosphor represented by EU ²⁺ _0.14 .

This phosphor 4 is an example of the first phosphor, and M ¹ = Si, M ² = Ca / Sr / Mg (molar ratio 49/50) in the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ . / 1), so that the ^{M 3 = Sr, X = Cl} , M 4 = Eu 2 +, a = 0.86, b = 0.17, surface c / (a + c) = 0.14 to prescribe the amount of the content c of M ⁴ It is a synthesized phosphor.

This phosphor 4 is a phosphor in which Mg is further contained in Ca and Sr as M ² elements, and is a phosphor in which cristobalite is produced in the phosphor by excessive addition of SiO ₂ in the mixing ratio of the raw materials.

In the production of the phosphor 4, first, each of the raw materials of SiO ₂ , CaCO ₃ , MgCO ₃ , SrCl ₂ · 6H ₂ O and Eu ₂ O ₃ has a molar ratio of SiO ₂ : CaCO ₃ : MgCO ₃ : SrCl ₂ · 6H ₂ Phosphor 4 was weighed to O: Eu ₂ O ₃ = 1.68: 0.45: 0.02: 1.0: 0.13, and then the present phosphor 4 was obtained in the same manner as the phosphor 1.

<Phosphor 5>

Phosphor represented by (Ca _4.67 Mg _0.5 ) (PO ₄ ) ₃ Cl: Eu _0.08 .

This phosphor 5 is an example of the second phosphor.

Preparation of the present phosphor 5, CaCO ₃ , MgCO ₃ , CaCl ₂ , CaHPO ₄ , and Eu ₂ O ₃ each of the raw materials are molar ratio of CaCO ₃ : MgCO ₃ : CaCl ₂ : CaHPO ₄ : Eu ₂ O ₃ = 0.42: 0.5: 3.0: 1.25: 0.04 was weighed, and each weighed raw material was put in alumina mortar to be pulverized and mixed for about 30 minutes to obtain a raw material mixture. The raw material mixture was placed in an alumina crucible and calcined at a temperature of 800 ° C. or higher and less than 1200 ° C. for 3 hours in an N ₂ atmosphere containing ₂ to 5% of H ₂ . The obtained baked material was wash | cleaned well with warm pure water, and this phosphor 5 was obtained.

<Comparative Phosphor 1>

As Comparative Phosphor 1, a phosphor represented by BaMgAl ₁₀ O ₁₇ : Eu, Mn (manufactured by Kasei Optonics Co., Ltd.) was used.

This phosphor is known to have excellent light resistance among the near-ultraviolet excitation green light-emitting phosphors added to the list in the national project "Development of High Efficiency All-Optical Compound Semiconductor (Akari Plan of the 21st Century)".

Comparative Phosphor 2

As a comparative phosphor 2, a phosphor represented by Sr ₅ (PO ₄ ) ₃ Cl: Eu (manufactured by Kaysei Optonics Co., Ltd.) was used.

This phosphor is known as a blue phosphor for three wavelength fluorescent lamps.

The crystal structures of the phosphors 1 to 5 were confirmed to be target crystal structures using an X-ray diffraction apparatus (RIG-Ultima3, manufactured by Rigaku Corporation, X-ray tube: Cu target encapsulation tube). Particularly, in the fluorescent materials 1 to 4 as the first fluorescent substance, two types of diffraction patterns represented by the following FIGS. 7 and 8 were confirmed.

FIG. 7 shows an X-ray diffraction pattern using Kα characteristic X-rays of Cu measured for phosphor 1. FIG.

FIG. 8 shows an X-ray diffraction pattern using Kα characteristic X-rays of Cu measured for phosphor 2. FIG.

7, 8, when the diffraction intensity of the highest intensity diffraction peak in which the diffraction angle 2θ exists in the range of 29.0 degrees or more and 30.5 degrees or less is set to 100 also in the X-ray diffraction pattern using the K-characteristic X-ray of any Cu A diffraction peak with a diffraction intensity of 50 or more exists in a range where the diffraction angle 2θ is 28.0 ° or more and 29.5 ° or less, and a peak having a diffraction intensity 8 or more exists in a range where the diffraction angle 2θ is 19.0 ° or more and 22.0 ° or less. , A peak having a diffraction intensity of 15 or more exists in a range where the diffraction angle 2θ is 25.0 ° or more and 28.0 ° or less, and a peak that exhibits a diffraction intensity 15 or more exists in a range where the diffraction angle 2θ is 34.5 ° or more and 37.5 ° or less. It turns out that the peak which shows diffraction intensity 10 or more exists in the range whose each 2 (theta) is 40.0 degrees or more and 42.5 degrees or less, and the diffraction angle 2 (theta) is 13.0 degrees or more and 15.0 degrees or less.

For this reason, it is suggested that the powder mother crystal, phosphor 1, and phosphor 2 all belong to the same crystal structure.

In Fig. 8, diffraction peaks not observed in the initial model are confirmed near 2θ = 21.7 °. As a result of qualitative analysis by X-ray diffraction, it was confirmed that this diffraction peak (arrow in the figure) originates in cristobalite.

For this reason, it is understood that phosphor 2 contains impurities, but the crystal structure belongs to the same crystal structure as the parent crystal or phosphor 1.

The composition ratios of the phosphors 1 to 4 (the values of a and b in the above general formula) are based on the above-described data relating to the crystal structure of the parent crystal, the electron probe microanalyzer (manufactured by Nippon Denshi Co., Ltd .: JOEL JXA-8800R) Measured and determined using.

<Evaluation Results of Phosphors 1 to 4>

For phosphors 1 to 4 and comparative phosphor 1, the integrated emission intensity under 400 nm excitation was measured. The measurement result is shown in Table 3 as a relative value which makes the fluorescent substance 1 for comparison 100.

TABLE 3

TABLE 3

Integral Luminous Intensity Ratio: Relative Value when Integral Luminous Intensity of Comparative Phosphor 1 is 100

In Table 3, Phosphors 1 to 4 exhibited at least 1.4 times the integrated emission intensity of Comparative Phosphor 1. For this reason, it can be seen that the phosphors 1 to 4 can be efficiently excited in the wavelength region around 400 nm to emit visible light of high emission intensity.

In addition, the cristobalite was produced in the phosphor by excessively adding SiO ₂ in the mixing ratio of the phosphor raw material is 2 to 4, it can be seen that indicates a better light emitting property than Phosphor 1.

9 shows the emission spectrum (solid line) of phosphor 1 under 400 nm excitation and the emission spectrum (dashed line) of comparative phosphor 1.

FIG. 10 shows the emission spectrum (solid line) of phosphor 2 under 400 nm excitation and the emission spectrum (dashed line) of comparative phosphor 1.

FIG. 11 shows the emission spectrum (solid line) of phosphor 3 under 400 nm excitation and the emission spectrum (dashed line) of comparative phosphor 1.

12 shows the emission spectrum (solid line) of phosphor 4 under 400 nm excitation and the emission spectrum (dashed line) of comparative phosphor 1.

In addition, the vertical axis | shaft of the graph in FIGS. 9-12 shows the relative light emission intensity of fluorescent substance 1-4 and a comparative fluorescent substance.

9 to 12, it is understood that the phosphors 1 to 4 all have peaks in the emission spectrum in the wavelength range of 560 nm to 590 nm, and their half widths are 100 nm or more. For this reason, it can be seen that the phosphors 1 to 4 can emit broad visible light having high color rendering properties.

13 shows an excitation spectrum of phosphor 1.

13 shows that the phosphor 1 has a peak in the excitation spectrum in the wavelength range of 350 nm to 430 nm. For this reason, it can be seen that phosphor 1 is efficiently excited in the wavelength region around 400 nm.

13 shows that the phosphor 1 hardly absorbs light in the wavelength range of 450 nm to 480 nm. For this reason, when the phosphor 1 and other phosphors emitting light in the wavelength range of 450 nm to 480 nm are used in combination, for example, when the phosphor 1 and the blue light emitting phosphor are combined to form a white light emitting device, the blue phosphor does not absorb light emitted. Therefore, a light emitting device having high luminous efficiency and little color unevenness can be configured.

<Evaluation result of phosphor 5>

The integrated luminescence intensity of the phosphor 5 and the comparative phosphor 2 was measured under 400 nm excitation, and as a result, the relative emission intensity of the phosphor 5 was 141 for the comparative phosphor 2 to be 100.

In Fig. 14, the emission spectrum (solid line) of phosphor 4 under 400 nm excitation and the emission spectrum (dashed line) of comparative phosphor 2 are shown.

It can be seen from FIG. 14 that the phosphor 4 has better luminescence intensity than the comparative phosphor 2. In addition, since the half width of the emission spectrum of the phosphor 5 is wide at 38 nm, it is expected to construct a white light emitting device having high color rendering property by using the phosphor 5. That is, in the white light emitting device using the combination of the LED emitting blue light and the phosphor emitting yellow light, the half width of the emission spectrum of the LED emitting blue light is about 20 nm. A white light emitting device used as a light source of blue light can obtain wider blue light, and high color rendering is expected.

15 shows an excitation spectrum of phosphor 5.

It can be seen from FIG. 15 that the phosphor 5 is efficiently excited by light in a wavelength range of 380 nm to 430 nm.

Next, the structure of the light-emitting device of an Example is explained in full detail.

<Configuration of Light Emitting Device (Type 1)>

The light emitting devices of Examples 1a to 1c and 2a to 2d use the following specific configurations in the first embodiment described above.

In addition, the structure of the following light emitting device is the structure common to Example 1a-1c, Example 2a-d2, the reference example 1, and the comparative example 1 except the kind of fluorescent substance used.

First, an aluminum nitride substrate was used as the substrate 2, and electrodes 3a (anode) and 3b (cathode) were formed on the surface using gold.

On the electrode 3a (anode), an LED having a light emission peak at 405 nm (1 mm in all directions) (Semi LEDs: MvpLED ^TM SL-V-U40AC) was used as the semiconductor light emitting element 4. The lower surface of this LED was adhere | attached on the silver paste (84-1LMISR4 made from Ablestick Co., Ltd.) dripped using the dispenser, and this silver paste was hardened for 1 hour in 175 degreeC environment.

In addition, a gold wire of Φ45 μm was used as the wire 6, and the gold wire was bonded to the upper electrode and the electrode 3b (cathode) of the LED by ultrasonic thermocompression bonding.

Further, using a silicone resin (JR6140, manufactured by Toray Dow Corning Silicon Co., Ltd.) as a binder member, a phosphor paste in which various phosphors or a mixture of plural kinds of phosphors was mixed to 30 vol% was produced, and the phosphor paste was prepared. After the coating on the upper surface of the semiconductor light emitting element 4 to have a thickness of 100 μm, the fluorescent layer 7 was formed by immobilization with a step curing of 40 minutes in an 80 ° C. environment and then 60 minutes in a 150 ° C. environment.

Based on the structure of the above phosphor and light emitting device (type 1), Examples 1a to 1c, Examples 2a to 2d, Reference Example 1, and Comparative Example 1 were prepared.

<Examples 1a to 1d>

In Examples 1a to 1d, Phosphors 1 to 4 were used as the first phosphor. As shown in Table 4, Example 1a represented Phosphor 1, Example 1b represented Phosphor 2, and Example 1c represented Phosphor 3, Example 1d produced the above-mentioned phosphor paste using phosphor 4, and produced the light emitting devices of Examples 1a-1d using these phosphor pastes.

<Examples 2a to 2d>

Examples 2a to 2d are examples in which phosphor 2 is used as the first phosphor and phosphor 5 is used as the second phosphor, and a mixture of phosphors 2 and phosphors 5 at a blending ratio (weight ratio) shown in Table 4 is obtained. The phosphor paste was produced, and the light emitting device of Examples 2a to 2d using these phosphor pastes was produced.

Reference Example 1

As the reference example 1, the above-mentioned phosphor paste was produced using only phosphor 5, and the light emitting device of reference example 1 using this phosphor paste was produced.

TABLE 4

Table 4

Comparative Example 1

Phosphor BaMgAl _lO 0 ₁₇ : Eu (blue), phosphor BaMgAl ₁₀ O ₁₇ : Eu, Mn (green) and phosphor La ₂ O ₂ S: Eu compounding ratio (weight ratio) 3 (blue): 12 (green): 85 (red ) And the above-mentioned phosphor paste was produced using the mixture mixed with), and the light-emitting device of the comparative example 1 using this phosphor paste was produced.

<Evaluation of Examples 1a to 1d and Examples 2a to 2d>

Each light emitting device was made to emit light by injecting a current of 10 mA in an integrating sphere, and the light emission ratio and spectral spectrum were measured with a spectrometer (CAS140B-152 manufactured by Instrument System). The measurement result is explained in full detail below.

Table 5 shows the light emission ratio, chromaticity coordinates (cx, cy), color temperature (K), and average color rendering index (Ra) when a driving current of 10 mA is applied to each light emitting device.

In addition, the luminous flux ratio is shown as a relative value which makes luminous flux 100 when the drive current of 10 mA is applied to the light emitting device of Comparative Example 1.

TABLE 5

Table 5

Luminous Flux Ratio: Relative value that sets the luminous flux to 100 when a driving current of 10 mA is applied to the light emitting device of Comparative Example 1

From Table 5, it can be seen that the light emitting device of any of the examples is a light emitting device having a high luminous flux six times higher than that of Comparative Example 1.

Moreover, while the color rendering property of the comparative example 1 is Ra22.8, it turns out that any Example is high color rendering property of Ra60 or more. In particular, it can be seen that Examples 2a to 2d using a mixture of Phosphor 1 and Phosphor 4 have a high color rendering property of Ra70 or higher.

Fig. 16 shows the chromaticity coordinates (cx, cy) on the chromaticity diagram of light emitted when a driving current of 10 mA is applied to each light emitting device.

In addition, the area shown as (alpha) in the figure is the area | region of the white regulation (JIS-D-5500) of a vehicle lamp.

From Table 5, it can be seen that the chromaticity coordinates of Example 1b using only the first phosphor (phosphor 2) are located in the yellow region, and the chromaticity coordinates of Reference Example 1 using only the second phosphor (phosphor 5) are located in the blue region. .

In addition, since chromaticity coordinates of Examples 2a to 2d using a mixture of the first phosphor (phosphor 2) and the second phosphor (phosphor 5) are mixed with the light of both phosphors, the chromaticity coordinates of Example 1b and Reference Example 1 It can be seen that the chromaticity coordinates are positioned in a substantially straight line. In addition, it is understood that the phosphors 2 and 5 have a complementary color relationship, the chromaticity coordinates of Examples 2a to 2d are located in the white region, and the color temperature is in the warm white to daylight region of 3000 to 4600K.

From the above results, it is possible to obtain a light emitting device having a light emission color having a desired chromaticity coordinate on a straight line connecting the chromaticity coordinates of the light emission colors of both phosphors by adjusting the compounding ratio of the first phosphor and the second phosphor of the present invention.

FIG. 17 shows the emission spectrum (solid line) of Example 1b and the emission spectrum (dashed line) of Comparative Example 1 when a driving current of 10 mA is applied to the light emitting devices of Example 1b and Comparative Example 1. FIG.

In addition, the vertical axis of the graph in FIG. 17 shows the relative light emission intensity of Example 1b and Comparative Example 1. FIG.

17 shows that the light emitting device of Example 1b shows a broad emission spectrum with respect to Comparative Example 1, and has a high color rendering property.

FIG. 18 shows the emission spectrum (solid line) of Example 2a and the emission spectrum (dashed line) of Comparative Example 1 when a driving current of 10 mA is applied to the light emitting devices of Example 2a and Comparative Example 1. FIG.

FIG. 19 shows the emission spectrum (solid line) of Example 2b and the emission spectrum (dashed line) of Comparative Example 1 when a driving current of 10 mA is applied to the light emitting devices of Example 2b and Comparative Example 1. FIG.

FIG. 20 shows the emission spectrum (solid line) of Example 2c and the emission spectrum (dashed line) of Comparative Example 1 when a driving current of 10 mA is applied to the light emitting devices of Example 2c and Comparative Example 1. FIG.

FIG. 21 shows the emission spectrum (solid line) of Example 2d and the emission spectrum (dashed line) of Comparative Example 1 when a driving current of 10 mA is applied to the light emitting devices of Example 2d and Comparative Example 1. FIG.

In addition, the vertical axis | shaft of the graph in FIGS. 18-21 shows the relative light emission intensity of Examples 2a-2d and the comparative example 1. As shown in FIG.

18 to 21, it can be seen that the light emitting devices of Examples 2a to 2d exhibit a broad emission spectrum with respect to Comparative Example 1 and are highly color rendering.

When the emission spectrum of the 450 nm to 480 nm wavelength range in FIGS. 18-21 and the emission spectrum of the fluorescent substance 4 shown in FIG. 14 are compared, the peak wavelength and half value width of both emission spectrums are substantially identical. For this reason, it can be seen that in the light emitting devices of Examples 2a to 2d, light emitted by the second phosphor (phosphor 5) is emitted almost without being absorbed by the first phosphor (phosphor 2).

<Configuration of Light Emitting Device (Type 2)>

The light emitting devices 3a to 3g of the examples use the following specific configurations in the third embodiment.

In addition, the structure of the following light emitting device is common for Examples 3a-3h and Comparative Examples 2a-2h except the kind of fluorescent substance used.

First, the cup-shaped molded article in which the electrode terminals 10a and 10b made of copper were integrated by insert molding using a polyphthalamide resin as the container 13 was produced.

Next, as the semiconductor light emitting element 4, an LED having a light emission peak at 405 nm (1 mm in all directions) (manufactured by Semi LEDs: MvpLED ^™ SL-V-U40AC) was disposed at the bottom of the cup-shaped molded article. A silver paste (84-1LMISR4, manufactured by Able Stick Co., Ltd.) was added dropwise onto the electrode terminal 10a (anode), and the lower surface of the LED was adhered onto the silver paste, and the silver paste was cured for 1 hour under a 175 ° C environment. I was.

A 45 μm gold wire was used as the wire 6, and the gold wire was bonded to the upper surface side electrode and the electrode 10b (cathode) of the LED by ultrasonic thermocompression bonding.

Next, a silicone resin (manufactured by Toray Dow Corning Silicon Co., Ltd .: JCR6140) was filled as a filling member to a position where the upper surface and the uniform surface of the container 13 were covered with the LED, and then 40 minutes in an 80 ° C environment. Immobilization with a 60 minute step cure under 150 ° C. environment.

Next, using a silicone resin (JCR6140 manufactured by Toray Dow Corning Silicone Co., Ltd.) as a binder member, a phosphor paste in which various phosphors or a mixture of plural kinds of phosphors was mixed so as to be 30 vol% was produced.

This phosphor paste was applied to a glass substrate as the transparent plate 13 at an arbitrary film thickness using spin coating, and then cured for 60 minutes in a 150 ° C environment to form a fluorescent layer 7.

Finally, the glass substrate was fixed to the upper surface of the cup-shaped molded article.

Based on the structure of the above fluorescent substance and the light emitting device (type 2), the following Examples 3a-3h and Comparative Examples 2a-2h were produced.

<Examples 3a to 3h>

Examples 3a to 3h are examples in which the phosphor 2 is used as the first phosphor, and the phosphor 5 is used as the second phosphor, and a compounding ratio (weight ratio) of phosphor 2 (sulfur) and phosphor 5 (blue) 37 (Sulfur): The phosphor paste was produced by using a mixture mixed at 63 (blue), and the phosphor layer 7 was coated with these phosphor pastes at individual rotational speeds and film thicknesses shown in Table 6 by using spin coating. To form the light emitting device of Examples 3a to 3h.

<Comparative Examples 2a to 2h>

Phosphor (Sr, Ba, Ca) ₂ SiO ₄ : Eu ²⁺ (sulfur) (hereinafter referred to as Comparative Phosphor 2) and Phosphor 5 (blue) in a mixture ratio (weight ratio) 27 (yellow): 73 (blue) To produce the above-mentioned phosphor paste, and using the spin coat to form the phosphor layer 7 coated at the individual rotational speeds and film thicknesses shown in Table 6, and the light emitting device of Comparative Examples 2a to 2h. Was produced.

<Evaluation of Examples 3a to 3h>

Each light emitting device was made to emit light by injecting a current of 10 mA in an integrating sphere, and measured by an instantaneous multi-metering system (MCPD-1000 manufactured by Otsuka Electronics Co., Ltd.) installed above the transparent plate 12. The measurement result is explained in full detail below.

Table 6 shows the rotational speed (rpm) of the spin coat when forming the fluorescent layers 7 of the respective light emitting devices, the film thickness of the fluorescent layer (µm), and the driving current of 10 mA to each light emitting device. The chromaticity coordinates (cx, cy) are shown.

TABLE 6

Table 6

22 shows chromaticity coordinates (cx, cy) of the light emitted when a driving current of 10 mA is applied to each light emitting device on the chromaticity diagram.

In Tables 6 and 22, in both Examples and Comparative Examples, the chromaticity is shifted in the yellow direction as the thickness of the fluorescent layer 7 becomes thicker. This is because the large yellow phosphors of the Stokes shift (phosphor 2, comparative phosphor 2) incorporated in the phosphor layer 7 absorb the fluorescence of the blue phosphor (phosphor 5) and are converted into yellow light, and this amount of conversion is the phosphor layer. It is a phenomenon that occurs because (7) is thicker.

When the Example and the Comparative Example are compared with respect to the chromaticity shift amount due to the change in the film thickness, the film thickness difference (205 µm) of Examples 3a and 3h and the film thickness difference (202 µm) of Comparative Examples 2a and 2h are almost the same. In contrast, the shift amount of chromaticity according to this is 0.07 in Examples and 0.19 in Comparative Examples, and there is a difference of about 2.6 times between them. This is due to the fact that the yellow phosphor (phosphor 2) included in the fluorescent layer 7 of the example is lower in excitation characteristics in the blue region than the yellow phosphor (comparative phosphor 2) included in the fluorescent layer 7 of the comparative example. .

For this reason, the comparative example can be realized only within the range of the defined film thickness (about 30 mu m) between 2b and 2d in the white defined region of the vehicle lamp shown as α in FIG. It can be realized within a wide film thickness range (about 190 mu m) between 3a and 3g. As a result, when the white light emitting device is composed of the phosphor used in the present embodiment, a light emitting device having a stable chromaticity can be configured without precisely controlling the coating amount of the phosphor, and a light emitting device having low cost in process control and yield can be manufactured. .

As mentioned above, although the fluorescent substance of this invention was demonstrated according to the Example, this invention is not limited to these Examples, Of course, various use of a change, improvement, a combination, etc. are considered.

The light emitting device of the present invention can be used in various kinds of lighting devices, such as lighting lamps, displays, vehicle lamps, signaling devices and the like.

In particular, the white light emitting device according to the present invention can be expected to be applied to a luminaire requiring high output white light such as a headlamp for a vehicle.

1 is a schematic cross-sectional view showing a first embodiment of a light emitting device of the present invention.

2 is a schematic cross-sectional view showing a second embodiment of the light emitting device of the present invention.

3 is a schematic cross-sectional view showing the third embodiment of the light emitting device of the present invention.

4 is a diagram illustrating an example of an X-ray diffraction photograph of a single crystal matrix crystal.

5 is a fitting diagram for X-ray diffraction (measurement 2) of powder matrix crystals.

6 is a fitting diagram for X-ray diffraction (measurement 3) of phosphor 1 of the present invention.

It is a figure which shows the measurement result of X-ray diffraction using the K (alpha) characteristic X ray of Cu with respect to the fluorescent substance 1 of this invention.

Fig. 8 is a graph showing the measurement results of X-ray diffraction using Kα characteristic X-rays of Cu for phosphor 2 of the present invention.

9 is a diagram showing the emission spectrum (solid line) of phosphor 1 and the emission spectrum (dashed line) of comparative phosphor 1. FIG.

10 is a diagram showing the emission spectrum (solid line) of the phosphor of phosphor 2 and the emission spectrum (dashed line) of comparative phosphor 1. FIG.

FIG. 11 is a diagram showing the emission spectrum (solid line) of phosphor 3 and the emission spectrum (dashed line) of comparative phosphor 1. FIG.

FIG. 12 is a diagram showing the emission spectrum (solid line) of phosphor 4 and the emission spectrum (dashed line) of comparative phosphor 1. FIG.

13 is a diagram illustrating an excitation spectrum of phosphor 1.

It is a figure which shows the emission spectrum (solid line) of the fluorescent substance 5, and the emission spectrum (dotted line) of the comparative fluorescent substance 2.

15 is a diagram showing an excitation spectrum of phosphor 5. FIG.

16 is a chromaticity diagram showing chromaticity coordinates of light emitted by an embodiment and the like.

Fig. 17 is the emission spectrum (solid line) of Example 1b of the present invention and the emission spectrum of Comparative Example 1;

It is a figure which shows the emission spectrum (solid line) of Example 2a of this invention, and the emission spectrum (dotted line) of Comparative Example 1. FIG.

It is a figure which shows the emission spectrum (solid line) of Example 2b of this invention, and the emission spectrum (dotted line) of Comparative Example 1. FIG.

20 is a diagram showing the emission spectrum (solid line) of Example 2c of the present invention and the emission spectrum (dashed line) of Comparative Example 1. FIG.

FIG. 21 is a diagram showing the emission spectrum (solid line) of Example 2d of the present invention and the emission spectrum (dashed line) of Comparative Example 1. FIG.

22 is a chromaticity diagram showing chromaticity coordinates of light emitted by an embodiment and the like.

<Description of the code>

1: light emitting device

2: substrate

3a: electrode (anode)

3b: electrode (cathode)

4: semiconductor light emitting element

5: mount member

6: wire

7: fluorescent layer

8: can cap

9: metal stem

10a: electrode terminal (anode)

10b: electrode terminal (cathode)

11: opening

12: transparent plate

13: Courage

14: filling member

Claims (22)

A light emitting device comprising a light emitting element emitting ultraviolet or short wavelength visible light and at least one phosphor excited by the ultraviolet or short wavelength visible light to emit visible light, As the phosphor, the general formula M ¹ O ₂ aM ² O bM ³ X ₂ : M ⁴ (Wherein M ¹ is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, and M ² is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn) , M ³ is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, X is at least one halogen element, M ⁴ is a rare earth element and Eu ^{2 +} selected from the group consisting of Mn Represents at least one element which is essential, where a is 0.1 ≦ a ≦ 1.3 and b is 0.1 ≦ b ≦ 0.25) A light emitting device comprising a first phosphor represented by. A light emitting device that emits ultraviolet or short wavelength visible light, and at least two or more kinds of phosphors that are excited by the ultraviolet or short wavelength visible light to emit visible light, and the visible light emitted by each phosphor has a complementary color relationship; A light emitting device configured to mix to obtain white light, As the phosphor, the general formula M ¹ O ₂ aM ² O bM ³ X ₂ : M ⁴ (Wherein M ¹ is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, and M ² is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn) , M ³ is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, X is at least one halogen element, M ⁴ is a rare earth element and Eu ^{2 +} selected from the group consisting of Mn At least one element which is essential, where a is 0.1 ≦ a ≦ 1.3, and b is 0.1 ≦ b ≦ 0.25); And a second phosphor that emits visible light having a complementary color relationship with visible light emitted by the first phosphor. The light emitting device according to claim 1 or 2, wherein when the content of M ⁴ in the general formula is c (molar ratio), 0.03 < c / (a + c) < 0.8. The light emitting device according to claim 1 or 2, wherein M ¹ in the formula is at least Si, and the proportion of Si is 80 mol% or more. The light emitting device according to claim 1 or 2, wherein M ² in the general formula has at least Ca and / or Sr, and the ratio of Ca and / or Sr is 60 mol% or more. The light emitting device according to claim 1 or 2, wherein M ³ in the general formula has at least Sr and Sr is 30 mol% or more. In the general formula described in claim 1 or 2, a is in the range of 0.30 ≦ a ≦ 1.2, b is 0.1 ≦ b ≦ 0.2, and the content c of M ⁴ is 0.05 ≦ c / (a + c) ≦. It is 0.5, The fluorescent substance characterized by the above-mentioned. The light emitting device according to claim 1 or 2, wherein X in the general formula is at least Cl, and the proportion of Cl is 50 mol% or more. The light emitting device according to claim 1 or 2, wherein the strong excitation band of the first phosphor is in a wavelength range of 350 to 430 nm. The light emitting device according to claim 1 or 2, wherein the peak of the emission spectrum of the first phosphor is in the wavelength range of 560 to 590 nm, and the half width is 100 nm or more. The light emitting device according to claim 1 or 2, wherein at least part of the crystals contained in the first phosphor is a crystal having a crystalline crystal structure. The crystal of claim 1 or 2, wherein at least a part of the crystals contained in the first phosphor is a crystal system: monoclinic, Bravay lattice: low-core monoclinic lattice, space group: crystal belonging to C2 / m. Light emitting device. The X-ray diffraction pattern using at least one of the crystals contained in the first fluorescent substance in the first phosphor, in a diffraction angle 2θ is in the range of 29.0 degrees or more and 30.5 degrees or less. When the diffraction intensity of the highest intensity diffraction peak is 100, the diffraction angle 2θ is in the range of 28.0 ° to 29.5 °, the diffraction angle 2θ is in the range of 19.0 ° to 22.0 ° and the diffraction angle 2θ is 25.0 ° A peak at least exhibiting diffraction intensity of 8 or more exists in a range of 28.0 degrees or less, a diffraction angle 2θ of 34.5 degrees or more and 37.5 degrees or less, and a diffraction angle 2θ of 40.0 degrees or more and 42.5 degrees or less, respectively. Light emitting device. The X-ray diffraction pattern using at least one of the crystals contained in the first fluorescent substance is a diffraction angle 2θ in a range of 28.0 ° or more and 29.5 ° or less according to claim 1 or 2. A diffraction peak with a diffraction intensity of 50 or more is present, a peak with a diffraction intensity of 8 or more is present in a range where the diffraction angle 2θ is between 19.0 ° and 22.0 °, and the diffraction angle is between 25.0 ° and 28.0 °. A peak indicating an intensity of 15 or more exists, and a peak indicating a diffraction intensity of 15 or more exists in a range in which the diffraction angle 2θ is 34.5 degrees or more and 37.5 degrees or less, and the diffraction intensity 10 is in a range in which the diffraction angle 2θ is 40.0 degrees or more and 42.5 degrees or less. The peak which shows the above and the diffraction intensity 10 or more exists in the range whose diffraction angle 2 (theta) is 13.0 degrees or more and 15.0 degrees or less is provided. The diffraction angle 2θ is in a range of 12.5 ° or more and 15.0 ° or less in a diffraction pattern using at least Kα characteristic X-rays of Mo, according to claim 1 or 2 When the diffraction intensity of the highest intensity diffraction peak is set to 100, a diffraction peak indicating a diffraction intensity of 50 or more exists in a range where the diffraction angle 2θ is 12.0 ° or more and 14.5 ° or less, and the diffraction angle 2θ is 8.0 ° to 10.5 ° A peak having a diffraction intensity of 8 or more exists in the following range, and a peak showing a diffraction intensity of 15 or more exists in a range in which the diffraction angle 2θ is 11.0 ° or more and 13.0 ° or less, and the diffraction angle 2θ is 15.5 ° or more and 17.0 ° or less. The peak which shows the diffraction intensity 15 or more exists in the range, and the diffraction intensity 2 or more represents the diffraction intensity 10 or more in the range of 17.5 degrees or more and 19.5 degrees or less, and the diffraction intensity 2 or more is 5.0 or more and 8.0 degrees or less, and the diffraction intensity is 10 or more Indicate The light emitting device is characterized in that a peak is present. The said 1st fluorescent substance is a mixture of the crystal | crystallization which has a characteristic as described in any one of Claims 11-15, and another crystalline phase or an amorphous phase, The mixture in Claim 1 or 2 characterized by the above-mentioned. The ratio of the said crystal of 20% by weight or more of the phosphor. The light emitting device according to claim 2, wherein the second phosphor is a blue light emitting phosphor. The light emitting device according to claim 2, wherein the peak of the emission spectrum of the second phosphor is in the wavelength range of 440 to 470 nm and the half width is 30 to 60 nm. The method of claim 2, wherein the second phosphor is represented by the general formula _{Ca x -y- z Mg y (PO} 4) 3 Cl: EU 2 + z (Where x is 4.95 <x <5.50, y is 0 <y <1.50, z is 0.02 <z <0.20, and y + z is 0.02≤y + z≤1.7) A light emitting device characterized in that the phosphor. The light emitting device according to claim 1 or 2, wherein a peak of an emission spectrum of the light emitting element is in a wavelength range of 350 to 430 nm. The light emitting device according to claim 1 or 2, wherein the light emitting element is a semiconductor light emitting element. The light emitting device according to claim 21, wherein the semiconductor light emitting element is an InGaN-based LED or LD.

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