JP5326777B2 - Phosphor and method for producing the same - Google Patents

Description

The present invention relates to a phosphor and a method for producing the same, and more particularly to a phosphor containing an alkali metal element and a method for producing the same.

  By combining the light source light emitted from the light emitting element and the wavelength conversion member that can be excited to emit light of a hue different from that of the light source light, light of various wavelengths can be emitted based on the principle of color mixing of light. Light emitting devices have been developed. For example, a phosphor that emits primary light from a short wavelength side corresponding to visible light from ultraviolet light from a light emitting element, and emits fluorescence of R, G, B (Red Green Blue) that is a wavelength conversion member by the emitted light. Is excited, the three primary colors of light, red, blue and green, are additively mixed to obtain white light. In particular, green phosphors have a high contribution to white color because of their large contribution to white, and various phosphors have been studied so far.

For example, an illumination unit that emits white light using an LED that emits UV radiation or blue light as a light source and a phosphor that is excited by the LED is disclosed (see Patent Document 1). In this illumination unit, calcium-magnesium-chlorosilicate (Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ ) activated with Eu is used as a phosphor emitting green light.

In general formula _{(Ca a, Sr b, Ba} c, Eu d) 8 Mg 1-x Mn x Si 4 O 16 Cl 2 ( where, 0 <a <1.0,0 ≦ b <0.5, A green light emitting phosphor represented by 0 ≦ c <0.5, 0 <d <0.2, a + b + c + d = 1.0, and 0 ≦ x <0.3 is disclosed (Patent Document 2). reference). Further, it is disclosed that, for the purpose of accelerating particle growth when manufacturing this green-emitting phosphor, an alkali metal halide such as LiCl, NaCl, or KCl is used as a flux.

Special Table 2003-535477 JP 2008-285576 A

However, as the phosphor used for the light-emitting device including the display and the illumination, the above-mentioned green light-emitting phosphor does not have sufficient luminance, and further improvement of the light emission characteristics is demanded. Further, as described later, the phosphor produced by adding a flux as described in Patent Document 2 has a low reflectance of 81.1% at 525 nm, so that it absorbs green light emitted from the phosphor. It was. Thereby, the luminance was not sufficient.
Therefore, the present invention has been made to solve such problems. That is, a main object of the present invention is to provide a phosphor that emits green light with high luminance and applicable to white light having excellent light emission characteristics and a method for manufacturing the same.

The phosphor of the present invention is a phosphor having a substantial composition represented by the following general formula and containing one or more alkali metal elements selected from the group of Na, K, Rb, and Cs. The phosphor has a reflectance of 82% or more at 525 nm.
M _x Eu _y MgSi _z O _a X _b
(In the above formula, M is at least one selected from the group of Ca, Sr, Ba, Zn, and Mn, X is at least one selected from the group of F, Cl, Br, and I, and 6.5 ≦ (x <8.0, 0.01 ≦ y ≦ 1.5, 3.5 ≦ z ≦ 4.3, a = x + y + 1 + 2z−b / 2, 0.8 ≦ b ≦ 2.2)

According to the phosphor of the present invention, a high-luminance green-emitting phosphor can be obtained.

The method for producing a phosphor according to the present invention is a method for producing a phosphor having a substantial composition represented by the following general formula: a compound containing a composition element of the phosphor, Na, K, Rb, A mixture containing one or more alkali metal element-containing compounds selected from the group of Cs is fired in a nitrogen atmosphere, and then fired in a reducing atmosphere consisting of hydrogen and nitrogen. Thereby, a high-luminance green-emitting phosphor can be obtained.
M _x Eu _y MgSi _z O _a X _b
(In the above formula, M is at least one selected from the group of Ca, Sr, Ba, Zn, and Mn, X is at least one selected from the group of F, Cl, Br, and I, and 6.5 ≦ (x <8.0, 0.01 ≦ y ≦ 1.5, 3.5 ≦ z ≦ 4.3, a = x + y + 1 + 2z−b / 2, 0.8 ≦ b ≦ 2.2)

The compound containing an alkali metal element is preferably added in a molar ratio of 0.01 to 2.0 with respect to Mg. Thereby, the particle growth of a fluorescent substance can be accelerated | stimulated suitably.

According to the present invention, since the reflectance at 525 nm is high and light having a wavelength near 525 nm is not absorbed, a high-luminance green-emitting phosphor can be obtained.

The reflection spectrum of the fluorescent substance which concerns on Example 1 is shown. The reflection spectrum of the fluorescent substance which concerns on Example 2 is shown. The reflection spectrum of the fluorescent substance which concerns on Example 10 is shown. The reflection spectrum of the fluorescent substance which concerns on Example 12 is shown. The reflection spectrum of the fluorescent substance concerning Example 14 is shown. The reflection spectrum of the fluorescent substance which concerns on Comparative Examples 1-3 is shown. The emission spectrum of the fluorescent substance which concerns on Example 1 and Comparative Examples 1-2 is shown. The excitation spectrum of the fluorescent substance concerning Example 1 is shown. 1 is a schematic cross-sectional view of a general light emitting device.

The embodiment described below exemplifies a phosphor and its manufacturing method for embodying the technical idea of the present invention, and is not limited to the following.

The relationship between the color name and chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, and the like comply with JIS Z8110. Specifically, 380 nm to 455 nm is blue purple, 455 nm to 485 nm is blue, 485 nm to 495 nm is blue green, 495 nm to 548 nm is green, 548 nm to 573 nm is yellow green, 573 nm to 584 nm is yellow, 584 nm to 610 nm is yellow red , 610 nm to 780 nm is red.

(Embodiment)
The phosphor according to the embodiment is a phosphor having a substantial composition represented by the following general formula and containing at least one alkali metal element selected from Na, K, Rb, and Cs, and reflecting at 525 nm The rate is 82% or more. Here, the substantial composition means that elements less than 1% of the elements contained in the phosphor are not displayed in the general formula of the composition.
M _x Eu _y MgSi _z O _a X _b : Eu
(In the above formula, M is at least one selected from the group of Ca, Sr, Ba, Zn, Mn,
X is at least one selected from the group consisting of F, Cl, Br, and I;
6.5 ≦ x <8.0, 0.01 ≦ y ≦ 1.5, 3.5 ≦ z ≦ 4.3, a = x + y + 1 + 2z−b / 2, and 0.8 ≦ b ≦ 2.2. )

This phosphor absorbs light in the short wavelength region from near ultraviolet to visible light and emits green light. Specifically, it is green light having an emission peak in a wavelength range of 495 nm to 548 nm in the emission spectrum of this phosphor. However, the emission peak can be intentionally varied by adjusting the amount of elements contained or the composition. In this specification, the short wavelength region from near ultraviolet to visible light is not particularly limited, but refers to a region of 250 to 490 nm.

This phosphor preferably has a reflectance at 525 nm of 82% or more. Since this phosphor emits green light, it is possible to reduce the loss of luminance and increase the luminance by suppressing the absorption of light in the vicinity of 525 nm by the phosphor itself. Moreover, since it is preferable to absorb the excitation light efficiently, the reflectance of the excitation light is preferably low.

For the measurement of the reflectance of the phosphor according to the embodiment, a reflectance measuring device F-4500 manufactured by Hitachi High-Technologies is used. The reflectance measuring method will be described below. A xenon lamp is used as the light source, and light from the light source is introduced into the first monochromator. Only the target wavelength of the introduced light is selected by the first monochromator and irradiated to the sample for which the reflectance is to be obtained. The light reflected by the sample is introduced into the second monochromator, and the second monochromator selects the same wavelength as that selected by the first monochromator. The light selected by the second monochromator is introduced into the photomultiplier tube and the light intensity is measured. Subsequently, the wavelength selected by the first monochromator and the second monochromator is changed synchronously, and the intensity of light in the desired wavelength range is measured. The reference sample of reflectance is calcium hydrogen phosphate (CaHPO ₄ ), and the intensity of light reflected from the reference sample is measured in the same procedure as the above-described sample. The reflectance at each wavelength was determined by calculating the measured light intensity using the following formula.

M in the general formula of this phosphor is preferably Ca, but it is also possible to use a Ca partially substituted with Sr, Ba, Zn, Mn. Thereby, the light emission peak can be shifted to the yellow-green region.

X in the general formula of this phosphor is preferably Cl, but it is also possible to use those in which a part of Cl is substituted with F, Br, or I. Further, in this phosphor, Eu, which is a rare earth, becomes the emission center. However, the present invention is not limited to Eu, and one obtained by replacing a part of Eu with another rare earth metal or alkaline earth metal and co-activating with Eu can also be used. Moreover, what substituted a part of Si by Ge, Sn, Ti, Zr, Hf, Al, Ga, In, and Tl can also be used. Furthermore, what substituted some oxygen with nitrogen can also be used. In this way, the emission color can be finely adjusted to a desired color tone.

This phosphor contains 0.1 ppm or more, preferably 1 ppm or more of an alkali metal element selected from Na, K, Rb, and Cs. By adding a compound containing these specific elements as a flux, it is possible to promote solid-phase reaction and form particles of uniform size. In addition to alkali metal elements, rare earth elements, boron, and the like can be added.

  Moreover, it is preferable that at least a part of this phosphor has a crystal. For example, since the glass body (amorphous) has a loose structure, there is a possibility that the component ratio in the phosphor is not constant and chromaticity unevenness occurs. Therefore, in order to avoid this, it is necessary to control the reaction conditions in the production process to be strictly uniform. On the other hand, the phosphor according to the embodiment is easy to manufacture and process because it is not a glass body but a crystalline particle. Further, this phosphor can be uniformly dissolved in an organic medium, and adjustment of a light emitting plastic or polymer thin film material can be easily achieved. Specifically, in the phosphor according to the embodiment, at least 50% by weight or more, more preferably 80% by weight or more has crystals. This indicates the proportion of the crystalline phase having luminescent properties, and if it has a crystalline phase of 50% by weight or more, light emission that can withstand practical use can be obtained. Therefore, the more crystal phases, the better. Thereby, the light emission luminance can be increased and the workability is improved.

 The particle size of the phosphor is preferably in the range of 1 μm to 50 μm, more preferably 5 μm to 30 μm, considering that it is mounted on the light emitting device. Moreover, it is preferable that the fluorescent substance which has this particle size is contained frequently. Furthermore, the particle size distribution is preferably distributed in a narrow range. By using a phosphor having a large particle size and having small particle size and particle size distribution variations and optically excellent characteristics, color unevenness is further suppressed and a light emitting device having a good color tone can be obtained. Therefore, a phosphor having a particle size in the above range has high light absorption and conversion efficiency.

(Production method)
Below, the manufacturing method of the fluorescent substance which concerns on embodiment is demonstrated. The phosphor is weighed so as to have a predetermined composition ratio using raw materials of simple elements, oxides, carbonates or nitrides of elements contained in the composition.

  Specifically, M amount, Eu amount, Mg amount, Si amount, X amount, and alkali metal element in the raw material mixture are M: Eu: Mg: Si: X: alkali metal element = (6.5-8. 0) :( 0.01-1.5): 1: (3.5-4.3) :( 1.5-3.3) :( 0.01-2.0) Weigh each raw material. In addition, a flux of rare earth elements or boron may be added as appropriate to the mixture of raw materials.

The weighed raw materials are mixed wet or dry using a mixer. The mixer can be pulverized using a pulverizer such as a vibration mill, a roll mill, a jet mill, or the like, in addition to a ball mill that is usually used industrially, to increase the specific surface area. In addition, in order to keep the specific surface area of the powder within a certain range, it is classified using a wet classifier such as a sedimentation tank, a hydrocyclone, and a centrifugal separator, and a dry classifier such as a cyclone and an air separator. You can also

This mixture is placed in a crucible such as SiC, quartz, alumina, or BN or in a plate-like boat and fired in a furnace. The fired product is pulverized, dispersed, filtered, etc. to obtain the target phosphor. Solid-liquid separation can be performed by industrially used methods such as filtration, suction filtration, pressure filtration, centrifugation, and decantation. Drying can be performed by industrially used apparatuses such as a vacuum dryer, a hot-air heating dryer, a conical dryer, and a rotary evaporator.

Here, firing in the phosphor manufacturing method according to the embodiment will be described in detail. The phosphor manufacturing method according to the embodiment is fired in two or more stages in which secondary firing is performed after primary firing. You may perform primary baking and secondary baking in multiple times, respectively. The primary firing can be performed in a nitrogen atmosphere or in the air, but is preferably in a nitrogen atmosphere. The secondary firing is preferably performed in a reducing atmosphere of hydrogen and nitrogen having high reducing power. In these firings, solid carbon can also be placed in the atmosphere in order to increase the reducing power. Further, the two or more steps of firing including primary firing and secondary firing are performed at 1000 ° C. to 1250 ° C. for 1 to 30 hours, respectively. In this way, a phosphor with improved brightness can be obtained by firing in two or more stages.

Usually, calcium-magnesium-chlorosilicate is fired in an atmosphere with high reducing power, such as a reducing atmosphere of hydrogen and nitrogen, without performing primary firing. In order to obtain a phosphor with high luminance and green emission, it is preferable to increase the ratio of Eu ²⁺ in the total Eu in the phosphor. In order to reduce Eu ³⁺ to Eu ²⁺ , This is because baking at is an important factor for improving luminance.

Although the reason why the luminance of the phosphor according to the embodiment is improved is not clear, the amount of evaporation of the compound containing the alkali metal element in the primary firing is larger than the firing in a reducing atmosphere of hydrogen and nitrogen, This is considered to affect the luminance of the phosphor. A compound containing an alkali metal element promotes the particle growth of the phosphor, while being mixed into the phosphor crystal to cause crystal defects. This is because the reflectance of light in the green region of the phosphor is considered to decrease. Therefore, it is preferable that the content of the compound containing the alkali metal element in the raw material mixture is small when the particle growth of the phosphor approaches saturation.

If so, if the firing is carried out in a reducing atmosphere of hydrogen and nitrogen without primary firing, the proportion of the compound containing an alkali metal element mixed in the composition during particle growth increases, and crystal defects increase. Therefore, the reflectance decreases. On the other hand, in the primary firing, since the amount of evaporation of the compound containing the alkali metal element is large during particle growth, the proportion of the compound containing the alkali metal element mixed in the crystal is small, and a phosphor having a high reflectance is obtained. It is done. Thereafter, secondary firing with high reducibility is performed to obtain a phosphor with high luminance.

Regarding the raw material of the phosphor, alkaline earth Mg, Ca, Sr, and Ba may be used in combination with a halogen salt and an oxide, carbonate, phosphate, silicate, etc. so as to have a predetermined halogen ratio. it can. In addition, when a halogen is introduced, an ammonium salt containing a halogen can be used instead of the alkaline earth halogen salt.

Further, Eu as the activator is preferably used alone, but halogen salts, oxides, carbonates, phosphates, silicates and the like can be used. Further, a part of Eu may be replaced by Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or the like. Moreover, when using the mixture which requires Eu, a compounding ratio can be changed as desired. Thus, by replacing a part of Eu with another element, the other element acts as a co-activation. As a result, the color tone can be changed, and the light emission characteristics can be adjusted. Further, a Eu compound may be used as a raw material. Specifically, europium oxide, metal europium, europium nitride, or the like can be used as the Eu compound. The raw material Eu may be an imide compound or an amide compound.

For Si and Mg in the phosphor composition, oxides and nitride compounds are preferably used, but imide compounds and amide compounds can also be used. For _{example, SiO 2, Si 3 N 4} , Si (NH 2) 2, Mg 2 Si, MgO and the like. On the other hand, by using only Si and Mg alone, it is possible to obtain a phosphor having good crystallinity at low cost. The Si- or Mg-containing compound preferably has a high purity, but may contain different elements such as B and Cu. Furthermore, a part of Si can be replaced with Ge, Sn, Ti, Zr, Hf, Al, Ga, In, and Tl.

Further, K, Na, Rb, and Cs of alkali metal elements to be added are usually added as chloride, carbonate, hydroxide, but are not limited thereto, bromide, iodide, fluoride, It may be a phosphate, sulfate, or other inorganic salt, or may be in a state already contained in another raw material.

Each raw material has an average particle size of about 0.1 μm or more and 15 μm or less, more preferably about 0.1 μm to 10 μm. It is preferable from the viewpoint of diameter control and the like, and when the particle diameter is not less than the above range, it can be achieved by pulverizing in a glove box in an argon atmosphere or a nitrogen atmosphere.

(Light emitting device)
A light emitting device equipped with a phosphor according to an embodiment will be described with reference to the drawings. However, the light emitting device described below is an example for embodying the technical idea of the present invention, and is not specified as follows.

A light-emitting device 100 shown in FIG. 9 includes a cup-shaped package 110 that is open at the top, and a light-emitting element 101 that is mounted in the cup-shaped package 110. It is filled with a sealing resin 103 containing. The light emitting element 101 is electrically connected to the positive and negative lead electrodes 111 formed on the surface of the package 110 in the cup via the conductive wire 104. The light emitting element 101 emits light upon receiving power supply from the outside via the lead electrode 111. The light emitted from the light emitting element 101 is transmitted through the sealing resin 103, and a part of the light is converted by the phosphor 102, and mixed color light is emitted from the top.

  In such a light emitting device 100, a means for reflecting the light emitted from the light emitting element 101 to the light extraction side by the reflecting member 112 is generally provided. The reflecting member 112 is generally a metal such as silver, gold, or aluminum, and is coated on the lead electrode 111.

(Light emitting element)
As the light-emitting element, one that emits light in a short wavelength region from near ultraviolet to visible light can be used. Light in the short wavelength region from near ultraviolet to visible light is not particularly limited, but refers to a region of 250 to 490 nm. In particular, the range of 290 nm to 470 nm is preferable. More preferably, it has an emission peak wavelength at 440 nm to 460 nm. This is because the phosphor according to the embodiment can be excited efficiently and visible light can be effectively used. In addition, by using a light emitting element as an excitation light source, a stable light emitting device with high efficiency, high output linearity with respect to input, and strong mechanical shock can be obtained.

(Phosphor)
The phosphor according to the embodiment can be used alone, but can also be used in combination with other phosphors. As a result, light emitting devices of various colors can be provided. Any other phosphor may be used as long as it absorbs light from the light emitting element or the phosphor according to the embodiment and converts the light into light having a different wavelength. For example, nitride phosphors / oxynitride phosphors / sialon phosphors mainly activated by lanthanoid elements such as Eu and Ce, lanthanoid elements such as Eu, and transition metal elements such as Mn. Alkaline earth halogen apatite phosphor, alkaline earth metal borate phosphor, alkaline earth metal aluminate phosphor, alkaline earth silicate, alkaline earth sulfide, alkaline earth thiogallate Organic earth mainly activated by lanthanoid elements such as alkaline earth silicon nitride, germanate or rare earth aluminate, rare earth silicate or Eu mainly activated by lanthanoid elements such as Ce and It is preferably at least one selected from organic complexes and the like. For example, (Ca, Sr, Ba) ₂ SiO ₄ : Eu, (Y, Gd) ₃ (Ga, Al) ₅ O ₁₂ : Ce, (Ca, Sr) ₂ Si ₅ N ₈ : Eu, CaAlSiN ₃ : Eu, etc. It is.

Example 1
In Example 1, in the charged composition ratio, CaCO ₃ : Eu ₂ O ₃ : MgO: SiO ₂ : CaCl ₂ : KCl = 6.25: 0.25: 1: 4: 1.25: 0.2 (Ca: Each raw material is weighed so that Eu: Mg: Si: Cl: K = 7.5: 0.5: 1: 4: 2.7: 0.2). Here, the charged composition ratio indicates the molar ratio of elements in the mixture of raw materials. Specifically, the following powders are weighed as raw materials for the phosphor of Example 1. However, the purity of each raw material is assumed to be 100%.
Calcium carbonate (CaCO ₃ ) ... 263.83 g
Europium oxide (Eu ₂ O ₃ ) ... 37.14 g
Magnesium oxide (MgO) 17.01 g
Silicon oxide (SiO ₂ ) ... 101.31 g
Calcium chloride (CaCl ₂ ) ... 77.57 g
Potassium chloride (KCl) ... 3.15g

The weighed raw materials are thoroughly mixed dry by a ball mill, and the mixture is fired in a furnace. Baking is performed in a nitrogen atmosphere at 1190 ° C. for about 4 hours (primary baking), and baking is performed in a reducing atmosphere of nitrogen and hydrogen at 1170 ° C. for about 4 hours (secondary baking). The fired product is pulverized and wet-dispersed to obtain a phosphor. An example of the reaction formula in the production of this phosphor is shown in the following chemical formula 1.

However, the above chemical formula is a theoretical formula based on the composition formula obtained from the analysis value, and in the actual product, a part of oxygen or chlorine may be removed, and the composition ratio may slightly change. Therefore, x and y represent the difference between the analytical value and the actual composition, and z represents the amount of scattered chlorine.

(Comparative Example 1)
In Comparative Example 1, a phosphor was obtained by performing the same operation as in Example 1 except that KCl was not added.

(Comparative Example 2)
In Comparative Example 2, a phosphor was obtained by the same operation as in Example 1 except that the primary firing was in a mixed reduction atmosphere of nitrogen and hydrogen at 1190 ° C.

(Comparative Example 3)
In Comparative Example 3, a phosphor was obtained by the same operation as in Example 1 except that LiCl was used instead of KCl.

Table 1 below shows the manufacturing conditions and characteristics of the phosphors of Example 1 and Comparative Examples 1-3. “Additive element” in Table 1 indicates the type of additive element, and “addition amount” indicates the molar ratio of the additive element to Mg when Mg in the mixture is 1 mol. “After N ₂ atmosphere, H ₂ / N ₂ atmosphere” indicates that the mixture is fired in an N ₂ atmosphere and then fired in an H ₂ / N ₂ atmosphere, and is otherwise indicated by x. . Further, as the characteristics of the phosphor, the center particle diameter, chromaticity coordinates, 52

The reflectance and brightness at 5 nm are shown. Note that the chromaticity coordinates and luminance are those at 460 nm excitation. The luminance indicates relative luminance when the luminance of Comparative Example 1 is 100%.

In addition, the center particle diameter in Table 1 was measured by the electric resistance method in a Coulter counter. Specifically, the phosphor was dispersed in a sodium phosphate solution, and the particle size was determined based on the electrical resistance generated when passing through the pores of the aperture tube. Moreover, the reflectance measurement apparatus F-4500 made from Hitachi High-Technologies was used for the measurement of a reflectance. As a reference sample for reflectance, calcium hydrogen phosphate (CaHPO ₄ ) was used.

  The phosphor of Example 1 had a reflectance of 85.3% at 525 nm, and showed higher luminance than the phosphors of Comparative Examples 1 to 3. In addition, the phosphor of Comparative Example 3 had low luminance despite the addition of Li, which is an alkali metal element.

(Examples 2 to 15)
In Examples 2 to 15, phosphors were obtained by performing the same operations as in Example 1 except that the types and amounts of alkali metal elements added to the raw material mixture were weighed as shown in Table 2. The method for measuring the characteristics of the phosphors of Examples 2 to 15 is the same as that of Example 1. The luminance in Table 2 indicates the relative luminance when the luminance of Comparative Example 1 is 100%.

Table 3 below shows values obtained by elemental analysis of the phosphors of Examples 1 to 15 and Comparative Example 4. The phosphor of Comparative Example 4 was obtained by performing the same operation as in Example 1 except that no alkali metal element was added and the firing was only in a reducing atmosphere of nitrogen and hydrogen at 1170 ° C. It was.

  When Table 3 is seen, as for the fluorescent substance of the comparative example 4 which does not contain an alkali metal element, K is less than 2 ppm, Rb is less than 5 ppm, Cs is less than 20 ppm. On the other hand, the phosphors of Examples 1 to 7 and 9 contain 5 ppm or more of K, the phosphor of Example 12 contains 290 ppm of Rb, and the phosphor of Example 14 contains 280 ppm of Cs. .

Table 4 below shows the composition ratio of the phosphors calculated from the elemental analysis values in Table 3. The composition ratio was expressed as a molar ratio of other elements with Mg as the standard.

The phosphor of the present invention and the method for producing the same are a white display with extremely excellent light emission characteristics using a fluorescent light emitting diode, a display, a PDP, a CRT, a FL, a FED, a projection tube, etc. Light sources, LED displays, backlight sources, traffic lights, illumination switches, various sensors, various indicators, and the like.

DESCRIPTION OF SYMBOLS 100 Light-emitting device 101 Light-emitting element 102 Phosphor 103 Sealing resin 104 Conductive wire 110 Package 111 Lead electrode 112 Reflective member

Claims (1)

A method for producing a phosphor represented by the following composition formula,
M _x Eu _y MgSi _z O _a X _b
(However, M is at least one selected from the group of Ca, Sr, Ba, Zn, Mn, X is at least one selected from the group of F, Cl, Br, I, 6.5 ≦ x <8.0, 0.01 ≦ y ≦ 1.5, 3.5 ≦ z ≦ 4.3, a = x + y + 1 + 2z−b / 2, 0.8 ≦ b ≦ 2.2.
A compound containing a composition element of the phosphor and a compound containing one or more alkali metal elements selected from the group of Na, K, Rb, and Cs are 0.01 to 2.0 with respect to Mg. A method for producing a phosphor, characterized by firing a mixture added at a molar ratio in a nitrogen atmosphere and then firing in a reducing atmosphere of hydrogen and nitrogen.

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