JP6058617B2 - Phosphor and method for producing phosphor - Google Patents

Description

The present invention relates to a phosphor that is efficiently excited and emitted by ultraviolet light or short-wavelength visible light.

Various light-emitting elements configured to obtain light of a desired color by combining a light-emitting element and a phosphor that is excited by light generated by the light-emitting element and generates light having a wavelength region different from that of the light-emitting element. The device is known.
In particular, in recent years, as a white light-emitting device with long life and low power consumption, semiconductor light-emitting diodes such as light-emitting diodes (LEDs) and laser diodes (LD) that emit ultraviolet light or short-wavelength visible light, and phosphors using these as light sources for excitation A light-emitting device configured to obtain white light by combining the above is drawing attention.
Specific examples of such a white light emitting device include (1) a method of combining an LED that emits blue light and a phosphor that emits yellow light when excited by blue light, and (2) emits purple light or ultraviolet light. A method is known in which an LED and a plurality of phosphors that emit light of colors such as red, green, blue, and yellow are excited by violet light or ultraviolet light.

Japanese Patent No. 3503139 JP 2005-126777 A JP 2003-110150 A

However, in the white light emitting device of the method (1), the color rendering property is low because there is almost no light in the middle wavelength region of blue and yellow and there is little light in the red region obtained from the phosphor. There was a problem. In addition, since the white light is obtained by mixing the light of the LED and the phosphor, for example, if the amount of the phosphor applied varies in the manufacturing process of the white light emitting device, the balance of the amount of light emitted by the LED and the phosphor As a result, the spectrum of white light obtained varies.
On the other hand, although the white light emitting device of the method (2) is excellent in color rendering, no phosphor having a strong excitation band in the ultraviolet region or the short wavelength visible light region has been found, and a high output white light device. Realization of a light emitting device was difficult. Therefore, there has been a strong demand for the development of a phosphor that has a strong excitation band in the ultraviolet region or the short wavelength visible light region and can efficiently emit visible light. In particular, the conventionally known indium-containing gallium nitride (InGaN) ultraviolet LED has good emission characteristics in the wavelength region near 400 nm, and is thus excited efficiently and emits high light in the wavelength region near 400 nm. Development of a phosphor capable of emitting intense visible light has been strongly desired.
In addition, in order to realize a light emitting device with high color rendering properties, it has been strongly desired to develop a phosphor having a broad emission spectrum.

  The present invention has been made in view of the above circumstances, and its purpose is to emit ultraviolet light or short-wavelength visible light, particularly visible light with high emission intensity that is efficiently excited in the wavelength region near 400 nm. The object is to provide a phosphor.

As a result of repeated studies to solve the above-mentioned problems, the inventors have a general formula of M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ (where M ¹ is Si, Ge, Ti, Zr And at least one element selected from the group consisting of Sn, M ² is at least one element selected from the group consisting of Ca, Sr, Mg, Ba and Zn, and M ³ is Mg, Ca, Sr, Ba and Zn at least one element selected from the group consisting of, X is at least one halogen element, M ⁴ is .a indicating at least one element essentially including Eu ²⁺ selected from the group consisting of rare earth elements and Mn The phosphor represented by 0.1 ≦ a ≦ 1.3 and b is in the range of 0.1 ≦ b ≦ 0.25) is effective in the ultraviolet or short wavelength visible light, particularly in the wavelength region near 400 nm. Emits visible light with high emission intensity when excited. As a result, the present invention has been completed.

That is, the phosphor according to the present invention has a general formula of M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ (where M ¹ is at least selected from the group consisting of Si, Ge, Ti, Zr and Sn). one element, at least one ^{M 2} is of Mg, Ca, Sr, at least one element selected from the group consisting of Ba and Zn, ^{M 3} is selected from the group consisting of Mg, Ca, Sr, Ba and Zn X represents at least one halogen element, M ⁴ represents at least one element essential to Eu ²⁺ selected from the group consisting of rare earth elements and Mn, and a represents 0.1 ≦ a ≦ 1.3. , B is in a range of 0.1 ≦ b ≦ 0.25).

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

Further, in the phosphor, M ^{1 in the} general formula requires at least Si and the ratio of Si is 80 mol% or more, and M ² in the general formula requires at least Ca and / or Sr, and Ca and And / or the ratio of Sr is 60 mol% or more, M ^{3 in the} above general formula requires at least Sr, Sr is 30 mol% or more, X in the general formula includes at least Cl, and the ratio of Cl is 50 mol%. % Or more is more preferable.

In the phosphor, a in the general formula is in the range of 0.3 ≦ a ≦ 1.2, b is in the range of 0.1 ≦ b ≦ 0.20, and the content c of M ⁴ is 0.00. It is more preferable that 05 ≦ c / (a + c) ≦ 0.5.

The production method of the phosphor of the present invention is not particularly limited, but at least the compounds represented by the following composition formulas (1) to (4) are included in the starting materials. The molar ratio is (1) :( 2) = 1: 0.1 to 1.0, (2) :( 3) = 1: 0.2 to 12.0, (2) :( 4) = 1: 0. 0.05 to 4.0, and can be obtained by mixing and firing the starting materials.
(1) M ¹ O ₂
(2) M ² O
(3) M ³ X ₂
(4) M ⁴
(Where ^{M 1} is at least one element of Si, Ge, Ti, at least one element selected from the group consisting of Zr and Sn, ^{M 2} is 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 Eu ²⁺ selected from the group consisting of rare earth elements and Mn. (Indicates at least one element that is essential.)

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

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

In addition, in the said starting material, it is preferable to weigh the excess of the raw material of said compositional formula (3) more than a stoichiometric ratio. This excessive addition takes into consideration that a part of the halogen element evaporates and evaporates during firing of the raw material mixture, and it is possible to prevent the occurrence of crystal defects of the phosphor due to the lack of the halogen element.
Further, this excessive addition also acts as a flux, contributing to reaction promotion and crystallinity improvement.

The crystal structure of the phosphor of the present invention is not particularly limited, but it is preferable that at least a part of the crystals contained in the phosphor is a crystal having a pyroxene type crystal structure.
Further, it is preferable that at least a part of the crystals contained in the phosphor is a crystal belonging to crystal system: monoclinic crystal, Brave lattice: bottom-centered monoclinic lattice, space group: C2 / m.

  The X-ray diffraction measurement result of the phosphor of the present invention is not particularly limited, but at least a part of the crystals contained in the phosphor is in an X-ray diffraction pattern using Cu Kα characteristic X-rays. The diffraction angle 2θ is 28.0 ° or more and 29.5 ° or less when the diffraction intensity of the highest diffraction peak existing in the range of diffraction angle 2θ of 29.0 ° or more and 30.5 ° or less is 100. There is a diffraction peak having a diffraction intensity of 50 or more, a diffraction angle 2θ of 19.0 ° to 22.0 ° is a peak having a diffraction intensity of 8 or more, and a diffraction angle 2θ of 25.0. There is a peak having a diffraction intensity of 15 or more in the range of from 0 ° to 28.0 °, and a peak having a diffraction intensity of 15 or more in the range of the diffraction angle 2θ of from 34.5 ° to 37.5 °. Diffraction intensity within the range of bending angle 2θ of 40.0 ° or more and 42.5 ° or less It represents 0 or more, and a diffraction angle 2θ is phosphor with a peak having a diffraction intensity of 10 or more in the range of 13.0 ° or 15.0 ° or less.

  Further, at least a part of the crystals contained in the phosphor has the highest intensity when the diffraction angle 2θ is in the range of 12.5 ° to 15.0 ° in the diffraction pattern using Mo Kα characteristic X-rays. When the diffraction intensity of the diffraction peak is 100, there is a diffraction peak showing a diffraction intensity of 50 or more in a range of diffraction angle 2θ of 12.0 ° or more and 14.5 ° or less, and diffraction angle 2θ of 8.0 ° or more. A peak showing a diffraction intensity of 8 or more exists in a range of 10.5 ° or less, a peak showing a diffraction intensity of 15 or more exists in a range of a diffraction angle 2θ of 11.0 ° or more and 13.0 ° or less, and a diffraction angle 2θ. In the range of 15.5 ° to 17.0 °, and the diffraction angle 2θ is in the range of 17.5 ° to 19.5 ° with a diffraction intensity of 10 or more. The diffraction intensity is 10 or more in the range where the bending angle 2θ is 5.0 ° or more and 8.0 ° or less Preferably a peak showing a exists.

  In the phosphor of the present invention, in order to obtain a higher emission intensity, it is desirable that the amount of the crystal contained in the phosphor is as large as possible, preferably composed of a single phase, and the content of the crystal is 20 It is desirable that it is at least mass%. More preferably, the emission intensity is remarkably improved at 50% by mass or more.

Incidentally, it is also possible that a characteristic composed of a mixture of the other crystal phase or amorphous phase within the range not lowering, in particular, the mixing ratio of the starting materials, SiO ₂ is excessively added, the crystal consists of SiO ₂ In the case of a phosphor in which quartz, tridymite, cristobalite or the like is synthesized as a slight byproduct, the emission intensity may be improved.

  The use of the phosphor of the present invention is not particularly limited, but various phosphors can be obtained by combining with the excitation light source.

  In the above light-emitting device, when ultraviolet light or short-wavelength visible light is used as an excitation light source, the phosphor of the present invention preferably has a strong excitation band in the wavelength region of 350 to 430 nm from the viewpoint of light emission efficiency, light emission luminance, and the like. .

  In the above light emitting device, when a white light emitting device is used, the phosphor of the present invention has an emission spectrum peak in a wavelength range of 560 to 590 nm and a half width of 100 nm or more in terms of color rendering properties and the like. To preferred.

  The phosphor of the present invention has a strong excitation band in the ultraviolet region or short-wavelength visible light region, and can emit visible light efficiently. In particular, light that is excited efficiently in the wavelength region near 400 nm and has a broad emission spectrum can be emitted.

  Moreover, if the phosphor of the present invention is used, a light-emitting device having excellent color rendering properties and high output can be obtained. Furthermore, by combining with other phosphors, it is possible to obtain a white light emitting device with excellent color rendering and high output.

It is a figure which shows an example of the X-ray-diffraction photograph of a single crystal base crystal. It is a fitting figure about the X-ray diffraction (measurement 2) of a powder base crystal. It is a figure which shows the X-ray-diffraction pattern of a powder base crystal and the fluorescent substance of Example 2 of this invention. It is a fitting figure of the X-ray diffraction (measurement 3) of the fluorescent substance of Example 1 of this invention. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 1 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 2 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 3 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 4 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 5 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the emission spectrum (solid line) of the fluorescent substance of Example 6 of this invention, and the emission spectrum (dotted line) of the fluorescent substance of the comparative example 1. It is a figure which shows the excitation spectrum of the fluorescent substance of Example 1 of this invention. It is a figure which shows the measurement result of the X-ray diffraction using the K alpha characteristic X ray of Cu about the fluorescent substance of Example 1 of this invention. It is a figure which shows the measurement result of the X ray diffraction which used the K alpha characteristic X ray of Cu about the fluorescent substance of Example 4 of this invention. It is a schematic sectional drawing which shows one Example of the light-emitting device using the fluorescent substance of this invention. It is drawing which shows the emission spectrum (solid line) of the light-emitting device of Example 7 of this invention, and the light emission spectrum (dotted line) of the light-emitting device of the comparative example 2. FIG.

  Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following examples.

The phosphor of the present invention can be obtained, for example, as follows.
In the phosphor of the present invention, compounds represented by the following composition formulas (1) to (4) can be used as raw materials.
(1) M ¹ O ₂ (M ¹ represents a tetravalent element such as Si, Ge, Ti, Zr, or Sn.)
(2) M ² O (M ² represents a divalent element such as Mg, Ca, Sr, Ba, Zn, etc.)
(3) M ³ X ₂ (M ³ is a divalent element such as Mg, Ca, Sr, Ba, Zn, etc., and X is a halogen element.)
(4) M ⁴ (M ⁴ represents a rare earth element such as Eu ²⁺ and / or Mn.)

As the raw material of the composition formula (1), for example, 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, a carbonate, oxide, hydroxide or the like of a divalent metal ion can be used.
Examples of the raw material of the composition formula (3) include 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, 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 used.
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, or the like can be used.

As a raw material of the composition formula (1), M ¹ is at least Si, which is at least one element selected from the group consisting of Si, Ge, Ti, Zr and Sn, and the ratio of Si is 80 mol%. The compound which is the above is preferable.
As a raw material of the composition formula (2), M ² is at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, at least Ca and / or Sr essential, and Ca and A compound having a ratio of / or Sr of 60 mol% or more is preferred.
As a raw material of the composition formula (3), M ³ is at least Sr essential, is at least one element selected from the group consisting of Mg, Ca, Sr, Mg, Ba and Zn, and Sr is 30 mol%. The above compounds are preferable, and the compound in which X is at least one halogen element in which at least Cl is essential and the proportion of Cl is 50 mol% or more is preferable.
As a raw material of the composition formula (4), M ⁴ is preferably a rare earth element in which divalent Eu is essential, and may contain a rare earth element other than Mn or Eu.

The molar ratio of the raw materials of the composition formulas (1) to (4) is (1) :( 2) = 1: 0.1 to 1.0, (2) :( 3) = 1: 0.2 to 12.0, (2) :( 4) = 1: 0.05-4.0, preferably (1) :( 2) = 1: 0.25-1.0, (2) :( 3) = 1: 0.3-6.0, (2) :( 4) = 1: 0.05-3.0, more preferably (1) :( 2) = 1: 0.25-1.0, (2): (3) = 1: 0.3-4.0, (2) :( 4) = 1: 0.05-3.0 Weighed and put each weighed raw material in an alumina mortar Grind and mix for 30 minutes to obtain a raw material mixture. This raw material mixture is put into an alumina crucible and fired in an electric furnace in a reducing atmosphere at (H ₂ / N ₂ ) in an atmosphere (5/95) at a temperature of 900 to 1100 ° C. for 3 to 40 hours to obtain a fired product. The phosphor of the present invention can be obtained by carefully washing the fired product with warm pure water and washing away excess chloride.

  In particular, the raw material (divalent metal halide) having the composition formula (3) is preferably weighed in excess of the stoichiometric ratio. This is because it is considered that a part of the halogen element is vaporized and evaporated during firing, and this is to prevent the occurrence of crystal defects in the phosphor due to the lack of the halogen element. In addition, the excessively added (3) raw material is liquefied at the calcination temperature, works as a solid-phase reaction flux, promotes the solid-phase reaction, and improves the crystallinity.

In addition, after baking of the said raw material mixture, the raw material of the composition formula of said (3) added excessively exists as an impurity in the manufactured fluorescent substance. Therefore, in order to obtain a phosphor having high purity and high emission intensity, it is necessary to wash away these impurities with warm pure water.
The composition ratio shown in the general formula of the phosphor of the present invention is the composition ratio after the impurities are washed away, and the raw material of the composition formula (3), which is added excessively and becomes impurities as described above, is in this composition ratio. Not taken into account.

  In order to obtain a phosphor with high luminous efficiency in the phosphor of the present invention, it is preferable to reduce the number of metal elements as impurities as much as possible. In particular, since transition metal elements such as Fe, Co, and Ni act as light emission inhibitors, use high-purity raw materials and mix impurities in the synthesis process so that the total of these elements is 500 ppm or less. It is preferable to prevent.

  Moreover, the phosphor of the present invention can be made into various light emitting devices by being combined with an excitation light source.

As the excitation light source, for example, a semiconductor light emitting element such as an LED or an LD, a light source for obtaining light emission from vacuum discharge or thermoluminescence, an electron beam excitation light emitting element, or the like can be used.
In particular, since the phosphor of the present invention is efficiently excited in the wavelength region near 400 nm and emits visible light with high emission intensity, it is preferably combined with an excitation light source that emits light in the wavelength region near 400 nm.

In combining these excitation light sources and the phosphor of the present invention, the phosphor powder of the present invention is dispersed in a transparent resin (silicone, fluorine, sol-gel silica, etc.) having good light resistance, and this is used as an excitation light source such as an LED. It can be fixed by applying it on top and curing the transparent resin.
At this time, it is preferable that the average particle diameter of the phosphor powder of the present invention is in the range of 0.1 to 20 μm from the viewpoint of dispersibility in transparent resin and applicability.

  For example, LED, LD, fluorescent lamp, fluorescent display tube (VFD), field emission display (FED), plasma display panel (PDP), cathode ray tube (CCFL) may be used as the light emitting device. In particular, the phosphor of the present invention is excellent in yellow light emission, and a white light emitting device can be formed by combining and mixing with other phosphors and / or other light sources. For example, a white light emitting device can be configured by using an LED or LD that emits ultraviolet light or short-wavelength visible light as an excitation light source, and combining the phosphor of the present invention with another blue region phosphor.

<Identification of crystal structure of phosphor of the present invention>
Determination of the crystal structure and the like of the phosphor of the present invention was carried out based on the analysis results obtained by growing a single crystal of a host crystal described below.
This base crystal has M ¹ = Si, M ² = Ca and Sr, M ³ = Sr, X = Cl in the general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ⁴ , and M ⁴ Is a substance that does not contain.

<Generation and analysis of parent crystals>
The crystal growth of the single crystal of the base crystal was performed by the following procedure.
First, each raw material of SiO ₂ , CaO, and SrCl ₂ was weighed so that the molar ratio thereof was SiO ₂ : CaO: SrCl ₂ = 1: 0.71: 1.07, and each weighed raw material was placed in an alumina mortar. The mixture was pulverized and mixed for about 30 minutes to obtain a raw material mixture. This raw material mixture was packed in a tablet mold and uniaxially compression molded at 100 MPa to obtain a molded body. The molded body was put in an alumina crucible and covered, and then fired in air at 1030 ° C. for 36 hours to obtain a fired product. The obtained fired product was washed with warm pure water and ultrasonic waves to obtain a base crystal.
A single crystal having a diameter of 0.2 mm was obtained in the base crystal thus produced.

About the obtained base crystal, the element quantitative analysis was performed with the following method, and the composition ratio (value of a, b in the said general formula) was determined.
1. Quantitative analysis of Si The base crystal was melted with sodium carbonate in a platinum crucible and then dissolved in diluted nitric acid to obtain a constant volume. About this solution, the amount of Si was measured using the ICP emission-spectral-analysis apparatus (SII nanotechnology Co., Ltd. product: SPS-4000).
2. Quantitative analysis of metal elements The base crystals were thermally decomposed with perchloric acid, nitric acid and hydrofluoric acid under an inert gas, and dissolved with dilute nitric acid to obtain a constant volume. About this solution, the amount of metal elements was measured using the ICP emission-spectral-analysis apparatus (SII nanotechnology Co., Ltd. product: SPS-4000).
3. Quantitative analysis of Cl The base crystals were burned in a tubular electric furnace, and the generated gas was adsorbed to the adsorbing liquid. The Cl amount of this solution was determined by ion chromatography using DX-500 manufactured by Dionex.
4). Quantitative analysis of O The base crystal was pyrolyzed in argon using a nitrogen oxygen analyzer TC-436 manufactured by LECO, and the generated oxygen was quantified by an infrared absorption method.

As a result of the above elemental quantitative analysis, the approximate composition ratio of the obtained host crystal is as follows.
SiO ₂ · 1.05 (Ca _0.6 , Sr _0.4 ) O · 0.15SrCl ₂
The specific gravity of the host crystal measured by a pycnometer was 3.4.

X-ray diffraction pattern using Mo Kα ray (wavelength λ = 0.71Å) was measured for the single crystal of the parent crystal by an imaging plate single crystal automatic X-ray structure analyzer (RIGAKU: R-AXIS RAPID). (Hereinafter referred to as measurement 1).
An example of an X-ray diffraction photograph obtained by this measurement 1 is shown in FIG.

  From measurement 1, the following crystal structure analysis was performed using 5709 diffraction spots obtained in the range of 2θ <60 ° (d> 0.71 Å).

For the parent crystal, the crystal system, Brave lattice, space group, and lattice constant of the parent crystal were determined from the X-ray diffraction pattern obtained by Measurement 1 using data processing software (Rigaku: Rapid Auto) as follows.
Crystalline system: Monoclinic Brave lattice: Bottom monoclinic lattice Space group: C2 / m
Lattice constant:
a = 13.3030 (12) Å
b = 8.3067 (8) Å
c = 9.1567 (12) Å
α = γ = 90 °
β = 110.226 (5) °
V = 949.50 (18) ^{３ 3}

Thereafter, a rough structure was determined by a direct method using crystal structure analysis software (manufactured by RIGAKU: Crystal Structure), and then structural parameters (seat occupancy, atomic coordinates, temperature factor, etc.) were refined by a least square method.
Refinement was performed on | F | of independent 1160 points with | F |> 2σ _F , and as a result, a crystal structure model with a reliability factor R ₁ = 2.7% was obtained.
The crystal structure model is hereinafter referred to as “initial structure model”.

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

The composition ratio of the initial structure model obtained 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 above analysis, it has been found that the crystal of the present invention is a crystal having a novel structure that is not registered in ICDD (International Center for Diffraction Date), which is an X-ray diffraction database widely used for X-ray diffraction.

  Next, the host crystal of the powder having the same form as the phosphor was prepared, and it was examined whether the crystal structure belonged to the initial structure model.

The powder base crystal was adjusted according to the following procedure. First, each raw material of SiO ₂ , CaO, SrO, and SrCl ₂ is weighed so that the molar ratio thereof is SiO ₂ : CaO: SrO: SrCl ₂ = 1.0: 0.7: 0.2: 1.0. Each raw material weighed was placed in an alumina mortar and ground and mixed for about 30 minutes to obtain a raw material mixture. This raw material mixture was packed in a tablet mold and uniaxially compression molded at 100 MPa to obtain a molded body. The molded body was placed in an alumina crucible and covered, and then fired at 1030 ° C. for 5 to 40 hours to obtain a fired product. The obtained fired product was washed with warm pure water and ultrasonic waves to obtain a powder base crystal.

Next, in order to obtain the detailed crystal structure of the powder base crystal, a powder X-ray diffraction measurement is performed using a Kα characteristic X-ray of Mo with a high-resolution powder X-ray diffractometer (manufactured by RIGAKU: custom-made) of Nagoya University. (Hereinafter referred to as measurement 2).
Rietveld analysis was performed on the result of measurement 2 to identify the crystal structure. In conducting the Rietveld analysis, the structural model was refined by the least-squares method using the lattice constant, atomic coordinates, and space 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 are in good agreement, and the R factor for determining the coincidence scale is a very small value of R _WP = 2.84%. Indicated. From this, the single crystal base crystal and the powder base crystal were determined to be crystals having the same structure.

FIG. 2 shows a Rietveld analysis fitting diagram for Measurement 2. FIG.
In the upper part of FIG. 2, the solid line is the powder X-ray diffraction pattern obtained by the calculation obtained by Rietveld analysis, and the cross plot shows the powder X diffraction pattern observed by the measurement 2.
The middle part in FIG. 2 shows the peak angle of diffraction by calculation obtained by Rietveld analysis.
The lower part in FIG. 2 is a plot of the difference between the calculated value and the observed value of the powder X-ray diffraction pattern shown in the upper part, and there is almost no difference between the two.

The lattice constant of the refined powder base 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) ^{３ 3}

Table 2 shows the atomic coordinates of the refined powder base crystal.

The theoretical composition ratio of the powder base crystal calculated by Rietveld analysis based on Measurement 2 is shown below.
<Theoretical composition ratio of powder base crystal>
SiO ₂ · 1.0 (Ca _0.6 , Sr _0.4 ) O · 0.17SrCl ₂

Elements that can form a solid solution in the host crystal are listed below.
Here, the solid solution is the same although the lattice constant is different from the parent crystal by changing the composition ratio of the elements constituting the parent crystal, or by substituting a part of the elements constituting the parent crystal with another element. It has a crystal structure of
<Elements that can be dissolved in the base crystal>
Si-substituted element of SiO ₂ : Ge, Ti, Zr, and Sn
Ca and / or Sr substitution 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 element of SrCl ₂ : F, Br, and I
In addition, a part of SiO ₂ composed of Group 4 element oxide can be replaced with 1/2 (B, P) O ₄ , 1/2 (Al, P) O ₄ .

<Identification of crystal structure of phosphor of the present invention>
Identification of the crystal structure of the solid solution can be determined by the identity of the diffraction results of X-ray diffraction or neutron diffraction, but a crystal in which a part of the constituent element is replaced with another element capable of solid solution from the original crystal Since the lattice constant changes, even if the crystal belongs to the same crystal structure as the original crystal, the diffraction results are not completely the same.
In crystals belonging to the same crystal structure, the diffraction angle shifts to the high angle side when the lattice constant decreases due to element replacement, and the diffraction angle shifts to the low angle side when the lattice constant increases.

Therefore, Eu ²⁺ (M ⁴ element in the general formula) in which the powder base crystal and a part of Ca and / or Sr (M ² element in the general formula) constituting the host crystal serve as the emission center of the phosphor. Whether the phosphors of the present invention (Example 1 and Example 2 to be described later) that were replaced with belong to the same crystal structure was evaluated using the following two determination methods.

First, in the case of a crystal having a small intrinsic amount, as a determination method for easily identifying the crystal structure, when the peak position (2θ) of the X-ray diffraction chart obtained from the X-ray diffraction result coincides with the main peak, both Can be determined to have the same crystal structure.
It should be noted that the main peak used for this determination is preferably determined by about ten peaks having the strongest diffraction intensity.

FIG. 3 shows an X-ray diffraction pattern of the phosphor of the present invention and the powder base crystal.
The upper row is a powder X-ray diffraction pattern of the phosphor of the present invention (Example 2 described later) using the wavelength of the Kα characteristic X-ray of Cu.
The lower row is a powder X-ray diffraction pattern for Cu Kα characteristic X-rays calculated from the crystal structure of the powder base crystal determined by Rietveld analysis.
From FIG. 3, it can be seen that the X-ray charts of both agree very well with respect to the main peak and are composed of the same crystal structure.

As a determination method for identifying the crystal structure in more detail, the result of X-ray diffraction (or neutron diffraction) to be determined is subjected to Rietveld analysis using the lattice constant, atomic coordinates, and space group of the initial crystal model as a model, It can be judged whether it is the same structure by calculating | requiring R factor.
Specifically, if the Rietveld analysis to be determined converges to a low R factor at the same level as the Rietveld analysis of the powder base crystal, it can be determined that the crystals have the same structure.
In addition, by comparing lattice constants and atomic coordinates obtained by Rietveld analysis, it is possible to discuss fine structural differences.

In order to use this determination method, first, an X-ray diffraction pattern of the phosphor of the present invention (Example 1 to be described later) was measured under the same conditions as in Measurement 2 (hereinafter referred to as Measurement 3).
Based on the obtained X-ray diffraction pattern, Rietveld analysis was performed using the initial structure model as a model. As a result, the R factor R _wp value of the criterion was very small as 3.69%, and converged at the same level as the R _wp value of the powder base crystal.
FIG. 4 shows a fitting diagram of Rietveld analysis for measurement 3.
In the upper part of FIG. 4, the solid line is the powder X-ray diffraction pattern calculated by Rietveld analysis, and the cross plot shows the powder X diffraction pattern observed by the measurement 3.
The middle part in FIG. 4 shows the peak angle of diffraction by calculation obtained by Rietveld analysis.
The lower part of FIG. 4 is a plot of the difference between the calculated value and the observed value of the powder X-ray diffraction pattern shown in the upper part.
From the above, it is determined that the phosphor of the present invention has the same crystal structure as the host crystal.

Hereinafter, the present invention will be described more specifically with reference to examples.
First, the phosphor of the present invention will be described with reference to examples. However, the following description of the chemical composition, raw material, production method, and the like of the phosphor does not limit the embodiment of the phosphor of the present invention.

<Example 1>
A phosphor represented by SiO ₂ · 0.9 (Ca _0.5 , Sr _0.5 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.1 .
In this example 1, the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ has M ¹ = Si, M ² = Ca / Sr (molar ratio 50/50), M ³ = Sr, A phosphor synthesized such that X = Cl, M ⁴ = Eu ²⁺ , a = 0.9, b = 0.17, and the content c (molar ratio) of M ⁴ is c / (a + c) = 0.1 It is.
In the manufacture of Example 1, first, SiO ₂ , Ca (OH) ₂ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ were used in 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 were weighed so, the raw materials were weighed and mixed placed about 30 minutes pulverized in an alumina mortar, raw A mixture was obtained. This raw material mixture was put into an alumina crucible and fired at 1030 ° C. for 5 to 95 hours (H ₂ / N ₂ ) in an atmosphere (5/95) in a reducing atmosphere electric furnace to obtain a fired product. The obtained fired product was carefully washed with warm pure water to obtain the phosphor of Example 1.

<Example 2>
A phosphor represented by SiO ₂ · 0.95 (Ca _0.65 , Sr _0.35 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.05 .
In this example 2, the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ , M ¹ = Si, M ² = Ca / Sr (molar ratio 65/35), M ³ = Sr, A phosphor synthesized such that X = Cl, M ⁴ = Eu ²⁺ , a = 0.95, b = 0.17, and the content c (molar ratio) of M ⁴ is c / (a + c) = 0.05 It is.
In the production of Example 2, first, SiO ₂ , Ca (OH) ₂ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ are used in a molar ratio of SiO ₂ : Ca (OH) _2. : SrCl ₂ · 6H ₂ O: Eu ₂ O ₃ = 1.0: 0.77: 1.0: 0.07 Weighed so as to be the same as that of Example 1 after that. A phosphor was obtained.

<Example 3>
A phosphor represented by SiO ₂ · 0.84 (Ca _0.55 , Sr _0.45 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.16 .
In this example 3, the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ has M ¹ = Si, M ² = Ca / Sr (molar ratio 55/45), M ³ = Sr, A phosphor synthesized such that X = Cl, M ⁴ = Eu ²⁺ , a = 0.84, b = 0.17, and the content c (molar ratio) of M ⁴ is c / (a + c) = 0.16 It is.
In the manufacture of Example 3, first, SiO ₂ , Ca (OH) ₂ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ were used in a molar ratio of SiO ₂ : Ca (OH) ₂ : SrCl. _{2 · 6H 2 O: Eu 2} O 3 = 1.0: 0.52: 1.0: were weighed so that 0.19, then the phosphor of the present example 3 in the same manner as in example 1 Got.

<Example 4>
A phosphor represented by SiO ₂ · 0.9 (Ca _0.6 , Sr _0.4 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.1 .
In this example 4, in the general formula M ¹ O ₂ .aM ² O.bM ³ X ₂ : M ⁴ , M ¹ = Si, M ² = Ca / Sr (molar ratio 60/40), M ³ = Sr, A phosphor synthesized such that X = Cl, M ⁴ = Eu ²⁺ , a = 0.9, b = 0.17, and the content c (molar ratio) of M ⁴ is c / (a + c) = 0.1 It is.
Further, Example 4 is an example in which cristobalite was generated in the phosphor by adding excessive SiO ₂ at the mixing ratio of the raw materials.
In the manufacture of Example 4, first, SiO ₂ , Ca (OH) ₂ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ were used in 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, then the phosphor of example 4 in the same manner as in example 1 Got.

<Example 5>
A phosphor represented by SiO ₂ · 0.86 (Ca _0.47 , Sr _0.52 , Ba _0.01 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.14 .
In Example 5, M ¹ = Si, M ² = Ca / Sr / Ba (molar ratio 47/52/1), M ⁴ in the general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ^{4 3} = Sr, X = Cl, M ⁴ = Eu ²⁺ , a = 0.86, b = 0.17, and an index c / (a + c) = 0.14 that defines the amount of content c of M ⁴ This is a phosphor synthesized.
In addition, Example 5 is an example in which Ba is added in addition to Ca and Sr as M ² elements, and cristobalite is generated in the phosphor by adding excessive SiO ₂ at the mixing ratio of raw materials. This is an example.
In the manufacture of Example 5, first, SiO ₂ , CaCO ₃ , BaCO ₃ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ are mixed at a molar ratio of SiO ₂ : CaCO ₃ : BaCO ₃ : SrCl _2. 6H ₂ O: Eu ₂ O ₃ = 1.68: 0.45: 0.02: 1.0: 0.13 Weighed so as to be the same as Example 1 and then Example 5 A phosphor was obtained.

<Example 6>
A phosphor represented by SiO ₂ · 0.86 (Ca _0.49 , Sr _0.50 , Mg _0.01 ) O · 0.17SrCl ₂ : Eu ²⁺ _0.14 .
In Example 6, M ¹ = Si, M ² = Ca / Sr / Mg (molar ratio 49/50/1), M ⁴ in the general formula M ¹ O ₂ · aM ² O · bM ³ X ₂ : M ^{4 3} = Sr, X = Cl, M ⁴ = Eu ²⁺ , a = 0.86, b = 0.17, and an index c / (a + c) = 0.14 that defines the amount of content c of M ⁴ This is a phosphor synthesized.
In addition, Example 5 is an example in which Mg is added in addition to Ca and Sr as M ² elements, and cristobalite is generated in the phosphor by adding excessive SiO ₂ at the mixing ratio of raw materials. This is an example.
In the manufacture of Example 6, first, SiO ₂ , CaCO ₃ , MgCO ₃ , SrCl ₂ .6H ₂ O, and Eu ₂ O ₃ are used in a molar ratio of SiO ₂ : CaCO ₃ : MgCO ₃ : SrCl _2. 6H ₂ O: Eu ₂ O ₃ = 1.68: 0.45: 0.02: 1.0: 0.13 Weighed so as to be the same as in Example 1 after that. A phosphor was obtained.

  The composition ratios of Examples 1 to 6 (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, an electronic probe microanalyzer (manufactured by JEOL: JOEL JXA-8800R). Was used to measure and determine.

<Comparative example>
As a comparative example, 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-excited green-emitting phosphors listed in the national project “Development of high-efficiency electro-optic conversion compound semiconductor (21st Century Lighting Project)”. Yes.

About the fluorescent substance of Examples 1-6 and a comparative example, the emitted light intensity under 400 nm excitation was measured. The measurement results are shown in Table 3 as relative values with the phosphor of the comparative example as 100.

From Table 3, the phosphors of Examples 1 to 6 have an integrated emission intensity at least 1.3 times that of Comparative Example 1. From this, it can be seen that the phosphors of Examples 1 to 6 are efficiently excited in the wavelength region near 400 nm and can emit visible light with high emission intensity.
Moreover, the addition of SiO ₂ excess in the mixing ratios of raw materials, Examples 4-6 which were generated cristobalite fluorescent body, that shows more excellent emission characteristics as compared with Examples 1 to 3 I understand.

FIG. 5 shows the emission spectrum (solid line) of the phosphor of Example 1 under excitation at 400 nm and the emission spectrum (dotted line) of Comparative Example 1.
FIG. 6 shows the emission spectrum (solid line) of the phosphor of Example 2 under 400 nm excitation and the emission spectrum (dotted line) of Comparative Example 1.
FIG. 7 shows the emission spectrum (solid line) of the phosphor of Example 3 under excitation at 400 nm and the emission spectrum (dotted line) of Comparative Example 1.
FIG. 8 shows the emission spectrum (solid line) of the phosphor of Example 4 and the emission spectrum (dotted line) of the phosphor of Comparative Example 1 under 400 nm excitation.
FIG. 9 shows the emission spectrum (solid line) of the phosphor of Example 5 and the emission spectrum (dotted line) of the phosphor of Comparative Example 1 under 400 nm excitation.
FIG. 10 shows the emission spectrum (solid line) of the phosphor of Example 6 and the emission spectrum (dotted line) of the phosphor of Comparative Example 1 under 400 nm excitation.
In addition, the vertical axis | shaft of the graph in FIGS. 5-10 shows the relative light emission intensity with a comparative example.

  5 to 10, it can be seen that the phosphors of Examples 1 to 6 all have an emission spectrum peak in the wavelength region of 560 to 590 nm and a half width of 100 nm or more. From this, it can be seen that the phosphors of Examples 1 to 6 can emit broad visible light with high color rendering properties.

FIG. 11 shows the excitation spectrum of the phosphor of Example 1.
From FIG. 11, it can be seen that the phosphor of Example 1 has a strong excitation band in the wavelength range of 350 to 430 nm. From this, it can be seen that the phosphor of Example 1 is efficiently excited in the wavelength region near 400 nm.
In addition, FIG. 11 shows that the phosphor of Example 1 hardly absorbs light in the wavelength region of 450 to 480 nm. From this, it can be seen that when the phosphor of Example 1 is mixed with blue color and synthesized white light, it does not absorb blue color and therefore there is little color shift.

FIG. 12 shows the X-ray diffraction pattern using Cu Kα characteristic X-rays measured for the phosphor of Example 1.
FIG. 13 shows an X-ray diffraction pattern using Cu Kα characteristic X-rays measured for the phosphor of Example 4.

12 to 13, in any X-ray diffraction pattern using the Kα characteristic X-ray of Cu, the diffraction peak 2θ having a diffraction angle 2θ in the range of 29.0 ° or more and 30.5 ° or less has the highest intensity. When the diffraction intensity is 100, a diffraction peak having a diffraction intensity of 50 or more exists in the range of the diffraction angle 2θ of 28.0 ° or more and 29.5 ° or less, and the diffraction angle 2θ is 19.0 ° or more and 22.0. There is a peak showing a diffraction intensity of 8 or more in the range of ° or less, a peak showing a diffraction intensity of 15 or more in a range of the diffraction angle 2θ of 25.0 ° or more and 28.0 ° or less, and a diffraction angle 2θ of 34. There is a peak showing a diffraction intensity of 15 or more in a range of 5 ° or more and 37.5 ° or less, a diffraction angle 2θ of 40.0 ° or more and 42.5 ° or less showing a diffraction intensity of 10 or more, and a diffraction angle 2θ of A diffraction intensity of 10 or more is exhibited in the range of 13.0 ° or more and 15.0 ° or less. It can be seen that over click is present.
This suggests that the powder base crystal, Example 1 and Example 4 all belong to the same crystal structure.

In addition, in FIG. 13, a diffraction peak (arrow in the figure) derived from cristobalite that cannot be confirmed in FIG. 12 can be confirmed near 2θ = 21.7 °.
From this, Example 4 contains impurities, but its crystal structure belongs to the same crystal structure as that of the parent crystal and Example 1, and its emission characteristics are better than those of Examples 1 to 3. I understand.

  Next, the usage pattern of the phosphor of the present invention will be described with reference to examples of the light emitting device. However, the mode of the following light emitting device does not limit the usage pattern of the phosphor of the present invention.

<Example 7 of Light Emitting Device>
FIG. 14 is a schematic cross-sectional view of a light emitting device using the phosphor of the present invention. In the light emitting device 1 shown in FIG. 14, electrodes 3 a and 3 b are formed on a substrate 2. A semiconductor light emitting element 4 as an excitation light source is fixed on the electrode 3 a by a mount member 5. The semiconductor light emitting element 4 and the electrode 3 a are energized by the mount member 5, and the semiconductor light emitting element 4 and the electrode 3 b are energized by the wire 6. A fluorescent layer 7 is formed on the semiconductor light emitting device.

The substrate 2 is preferably formed of a material that has no electrical conductivity but high thermal conductivity. For example, a ceramic substrate (aluminum nitride substrate, alumina substrate, mullite substrate, glass ceramic substrate), a glass epoxy substrate, or the like is used. be able to.
In this example, an aluminum nitride substrate was used.

The electrodes 3a and 3b are conductive layers formed of a metal material such as gold or copper.
In this embodiment, the electrode 3a is an anode, the electrode 3b is a cathode, and is provided on the substrate 2 using gold.

The semiconductor light-emitting element 4 is an example of an excitation light source when the phosphor of the present invention is used in a light-emitting device. For example, an LED or LD that emits ultraviolet light or short-wavelength visible light can be used. Specific examples include InGaN-based compound semiconductors. The emission wavelength range of the InGaN-based compound semiconductor varies depending on the In content. When the In content is large, the emission wavelength is long, and when it is small, the wavelength tends to be short. However, InGaN-based compound semiconductors containing In such a degree that the peak wavelength is around 400 nm are quantum in electro-optic conversion. The results show the highest efficiency.
In this example, a 1 mm square LED (SemiLEDs: MvpLED ^™ SL-V-U40AC) having an emission peak at 405 nm was used.

The mount member 5 is a conductive adhesive such as silver paste, for example, and fixes the lower surface of the semiconductor light emitting element 4 to the electrode 3a, and electrically connects the lower surface side electrode of the semiconductor light emitting element 4 and the electrode 3a on the substrate 2. To do.
In this example, a silver paste (manufactured by Able Stick: 84-1LMISR4) is dropped onto the electrode 3a using a dispenser, and the lower surface of the semiconductor light-emitting element 4 is adhered onto the silver paste under an environment of 175 ° C. Cured for 1 hour.

The wire 6 is a conductive member such as a gold wire, and is bonded to the upper surface side electrode of the semiconductor light emitting element 4 and the electrode 3b by, for example, ultrasonic thermocompression bonding, and electrically connects both.
In this example, a Φ45 μm gold wire was bonded to the upper surface side electrode of the semiconductor light emitting element 4 and the electrode 3b on the substrate 2 by ultrasonic thermocompression bonding.

In the phosphor layer 7, at least one or more kinds of phosphors including the phosphor of the present invention are sealed in a film shape covering the upper surface of the semiconductor light emitting element 4 with a binder member. For example, such a phosphor layer 7 is prepared by preparing a phosphor paste in which a phosphor is mixed in a liquid or gel binder member, and then applying the phosphor paste on the upper surface of the semiconductor light emitting element 4. It can be formed by curing the binder member of the phosphor paste.
As the binder member, for example, a silicone resin or a fluorine resin can be used. In particular, since the phosphor of the present invention preferably uses light having a wavelength region near 400 nm as excitation light, it is preferable to use a binder member having excellent ultraviolet resistance.

  The fluorescent layer 7 can be mixed with one or more kinds of phosphors having emission characteristics different from those of the phosphor of the present invention. As a result, light of various colors can be obtained by combining light of a plurality of different wavelength ranges.

  The fluorescent layer 7 can also be mixed with substances other than phosphors having various physical properties. For example, the refractive index of the fluorescent layer 7 can be increased by mixing a substance having a higher refractive index than that of a binder member such as metal oxide or sulfide into the fluorescent layer 7. As a result, it is possible to reduce the total reflection that occurs when the light generated from the semiconductor light emitting element 4 enters the fluorescent layer 7 and to improve the efficiency of taking excitation light into the fluorescent layer 7. Furthermore, the refractive index can be increased without reducing the transparency of the fluorescent layer 7 by making the particle size of the substance to be mixed nanosize.

In this example, a silicone resin (manufactured by Toray Dow Corning Silicone Co., Ltd .: JCR6140) was used as a binder member, and a phosphor paste was prepared in which the phosphor mixture was mixed to 30 vol%. This phosphor paste Was applied to the upper surface of the semiconductor light emitting element 4 at a thickness of 100 μm, and then fixed by step curing for 40 minutes in an 80 ° C. environment and then for 60 minutes in a 150 ° C. environment, thereby forming the fluorescent layer 7.
<Phosphor used in Example 7>
The phosphor (yellow) of Example 4 of the present invention and phosphor Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu (blue) (made by Kasei Optronics: KY-663) are blended (weight ratio) 1 (yellow) : A mixture of phosphors mixed at 1.5 (blue) was used.
<Phosphor used in Comparative Example 2>
As a comparative example, a phosphor BaMgAl ₁₀ O ₁₇ : Eu (blue), a phosphor BaMgAl ₁₀ O ₁₇ : Eu, Mn (green), and a phosphor La ₂ O ₂ S: Eu are mixed in a ratio (weight ratio) 3 (blue). ): 12 (green): A mixture of phosphors confused with 85 (red) was used.

  In the light emitting device 1 configured as described above, when a driving current is applied to the electrodes 3a and 3b, the semiconductor light emitting element 4 is energized, and the semiconductor light emitting element 4 is directed toward the fluorescent layer 7 by ultraviolet rays, short wavelength visible light, or the like. The light of the wavelength range specific to the semiconductor light emitting element 4 is irradiated. The phosphor in the phosphor layer 7 is excited by this light, and the phosphor emits light in a specific wavelength region. By utilizing such a mechanism, the light emitting device that emits desired light can be obtained by variously selecting the semiconductor light emitting element 4 and / or the phosphor.

The light emitting devices of Example 7 and Comparative Example 2 were made to emit light by supplying a current of 1 to 50 mA in an integrating sphere, and the light emission output was measured with a spectroscope (manufactured by Instrument System: CAS140B-152). The results are described in detail below.
The light emitting device of Comparative Example 2 was a light emitting device having the same configuration as that of Example 5 except for the phosphor material, and the measurement was performed under the same conditions.

Table 4 shows the light emission output (light flux) of each light emitting device when a driving current of 5, 10, 50 mA is applied to the light emitting devices of Example 7 and Comparative Example 2, and the driving current of 5 mA to the light emitting device of Comparative Example 2. It shows as a relative value where the light emission output (light beam) when 1.0 is applied is 1.0.
From Table 4, it can be seen that the light-emitting device of Example 7 is a higher-power light-emitting device than Comparative Example 2.

FIG. 15 shows an emission spectrum of each light-emitting device when a drive current of 50 mA is applied to the light-emitting devices of Example 7 and Comparative Example 2.
In addition, the vertical axis | shaft of the graph in FIG. 15 shows relative light emission intensity with a comparative example.
FIG. 15 shows that the light-emitting device of Example 7 shows a broad emission spectrum compared to Comparative Example 2, and has high color rendering properties (Ra = 76).

  As described above, the phosphor of the present invention has been described with reference to the examples. However, the present invention is not limited to these examples, and it is needless to say that various modifications, improvements, combinations, usage forms, and the like can be considered.

  The phosphor of the present invention can be used in various light emitting devices.

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

Claims (5)

The general formula is SiO ₂ · aMO · bSrCl ₂ : Eu ²⁺
(However, M represents an element essential for at least Ca and Sr selected from the group consisting of Mg, Ca, Sr and Ba, and the proportion of Ca and Sr in all elements of M (Mg, Ca, Sr and Ba) Is greater than 60 mol%, a is 0.1 ≦ a ≦ 1.3, and b is in the range of 0.1 ≦ b ≦ 0.25. 2. The phosphor according to claim 1, wherein 0.03 <c / (a + c) <0.8, where c is a molar ratio of Eu ^{2+ in} the general formula. In the above general formula, a is in the range of 0.30 ≦ a ≦ 1.2, b is in the range of 0.1 ≦ b ≦ 0.2, and the Eu ²⁺ content c is 0.05 ≦ c / (a + c). The phosphor according to claim 1, wherein ≦ 0.5. In the starting materials, at least the compounds represented by the composition formulas (1) to (4) below are used, and the molar ratio of these compounds is (1) :( 2) = 1: 0.1 to 1.0. , (2) :( 3) = 1: 0.2-12.0, (2) :( 4) = 1: 0.05-4.0, the starting materials are mixed and the method for producing a phosphor, wherein the calcination child.
(1) SiO ₂
(2) MO
(3) SrCl ₂
(4) Eu ²⁺
(However, M represents an element essential for at least Ca and Sr selected from the group consisting of Mg, Ca, Sr and Ba, and the proportion of Ca and Sr in all elements of M (Mg, Ca, Sr and Ba) Is greater than 60 mol%.) The phosphor according to any one of claims 1 to 3 , wherein there is a strong excitation band in a wavelength region of 350 to 430 nm.