TWI651292B - Phosphor, illuminating device and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a SiAlON phosphor that can efficiently excite in the wavelength range of ultraviolet to near ultraviolet to emit blue light, a method for manufacturing the same, and a light-emitting device using the same.

The fluorescent system of the present invention is represented by the general formula: Me _a Eu _b Al _c Si _d O _e N _f , and the composition ratios a, b, c, d, e, and f are a + b = 1, 0.01 <b <0.20 , 1.65 <c <2.50, 2.50 <d <4.00, 3.15 <e <4.90, and 2.80 <f <4.30, Me is either or both of Sr and Ba, and when excited by near-ultraviolet or purple light, in The wavelength of 450 to 485 nm performs blue light emission with a peak. The average diffuse reflectance at a wavelength of 700 to 800 nm is 90% or more, and the diffuse reflectance at a fluorescent peak wavelength is 85% or more.

Description

Phosphor, light emitting device and manufacturing method thereof

The present invention relates to a SiAlON-based phosphor that is efficiently excited to emit blue light in a wavelength range from ultraviolet to near ultraviolet, a method for manufacturing the same, and a light-emitting device using the same. .

Regarding phosphors having excellent chemical stability, heat resistance, and durability, nitrides and oxynitride phosphors with stable crystal structures have attracted attention. Among them, the representative aspect of nitrides and oxynitrides is the widespread use of Sialon phosphors.

Patent Document 1 proposes a β-sialon phosphor activated by Eu with excellent luminous efficiency, which corresponds to an absorption at 25 ° C of g = 2.00 ± 0.02 in measurement based on an electron spin resonance spectrum. The spin density is controlled to be 2.0 × 10 ¹⁷ spins / g or less. By controlling the spin density, the absorption of light that does not accompany the emission of light from the parent crystal itself is reduced, and the luminous efficiency can be improved. In particular, the luminous efficiency of the phosphors specifically disclosed in the examples has been shown to have improved by 39 to 58%.

[Prior technical literature] [Patent Literature]

International Publication No. 2008/062781

However, the efficient absorption of the excitation light from the light-emitting source and the light-emitting system are not limited to LED applications, but are characteristics required for all phosphor applications. Therefore, it is required to further improve the luminous efficiency.

In order to solve the above-mentioned problems, the present inventors carefully studied and reviewed the crystal structure and optical characteristics of Sialon phosphors, and found that by setting the composition ratio of the elements constituting the phosphors in a specific range and controlling the wavelength to 700 ~ The average diffuse reflectance at 800 nm and the diffuse reflectance at the peak wavelength of fluorescence can obviously improve the luminous efficiency, and even complete the present invention.

That is, an object of the present invention is to provide a phosphor, which is represented by the general formula: Me _a Eu _b Al _c Si _d O _e N _f , and the composition ratios a, b, c, d, e, and f are, a + b = 1, 0.01 <b <0.20, 1.65 <c <2.50, 2.50 <d <4.00, 3.15 <e <4.90, and 2.80 <f <4.30, Me is either or both of Sr and Ba, in near ultraviolet When it is excited by purple or purple light, it emits blue light with a peak in a wavelength range of 450 to 485 nm. The average diffuse reflectance of the phosphor at a wavelength of 700 to 800 nm is more than 90%. The diffuse reflectance at the peak wavelength of the fluorescent light is More than 85%.

Another object of the present invention is to provide a method for producing a phosphor, which comprises a mixing step of mixing raw materials, a baking step of raw materials after the baking mixing step, and an annealing treatment of the fired product after the baking step. The annealing step and the raw materials for supplying Sr and / or Ba in the mixing step are methods for producing such aluminate phosphors.

Another object of the present invention is to provide a light-emitting device including the above-mentioned phosphor and a light-emitting light source.

By controlling the composition ratio and diffuse reflectance of the phosphor, the fluorescent system of the present invention can achieve higher luminous efficiency than the conventional Sialon phosphor. In addition, according to the method for producing a phosphor of the present invention, it is possible to produce a phosphor having excellent light emission characteristics as described above with good reproducibility. In addition, the light-emitting device of the present invention can realize a light-emitting device having excellent brightness by using a phosphor having a high light-emitting efficiency as described above.

FIG. 1 is a graph showing diffuse reflectance (%) at excitation wavelengths of 450 nm to 800 nm of the phosphors described in Examples 1 to 2 and Comparative Examples 1 to 2. FIG.

[Form of Implementing Invention] <Fluorescent body> Composition

The fluorescent system involved in the present invention is represented by the general formula: Me _a Eu _b Al _c Si _d O _e N _f . This general formula represents the composition formula of a phosphor, and the ratio of a to f elements. In this specification, unless otherwise stated, the composition ratios a, b, c, d, e, and f are numerical values calculated when a + b = 1. Needless to say, the element ratio of an arbitrary number multiplied by a to f can also be regarded as the same composition formula.

The composition ratio in the case calculated as a + b = 1 a, b, c, d, e, and f are: a + b = 1, 0.01 <b <0.20, 1.65 <c <2.50, 2.50 <d <4.00, 3.15 <e <4.90, and 2.80 <f <4.30.

When the composition ratios a to f deviate from this range, the crystal structure of the phosphor becomes unstable, the formation of the second phase is promoted, and the diffuse reflectance is decreased. As a result, the non-luminous absorption of the parent crystal is increased, and the luminous efficiency is reduced.

Where b represents the ion concentration of the light-emitting element Eu, in When 0.01 or less, the number of light-emitting element ions is small, so sufficient luminous efficiency cannot be obtained. When it is 0.20 or more, the formation of the second phase is promoted. When the number of light-emitting element ions becomes too large, the so-called As a result of the phenomenon of extinction of the concentration of the reabsorption effect of the excitation energy, the luminous intensity may be reduced. The b representing the ion concentration of Eu is more preferably in the range of 0.015 <b <0.15, and more preferably 0.020 <b <0.100.

In addition, Me in the general formula is either one of Sr and Ba or both sides. The reason why Me is set to either or both of Sr and Ba is that, as the element Me, the crystalline structure can be maintained in the Ba system, and Sr is solid-solution substituted in the crystalline structure at all ratios.

2. Diffusion reflectance

In addition to satisfying the characteristics of the composition described above, the phosphor of the present invention sets the diffuse reflectance in a specific wavelength range as one of the characteristics in a specified numerical range. That is, the average diffuse reflectance at a wavelength of 700 to 800 nm is 90% or more, more preferably 94% or more, and the diffuse reflectance at a fluorescent peak wavelength is 85% or more, and more preferably 87% or more.

The reason why the luminous efficiency is significantly improved by controlling the diffuse reflectance to the above range can be considered mainly as follows.

That is, since the light emission of the phosphor is generated by the electron migration of Eu ²⁺ ions that become the light emission center, generally, the absorption of light that does not accompany the parent crystal is less, and the higher the light transmission, the more efficient the light emission. Promotion. The diffuse reflectance is a process in which the light diffusion in the phosphor powder is reduced due to the absorption of light. Therefore, the higher the diffuse reflectance is, the higher the light transmittance is. For example, since the fluorescent system represented by the general formula: Me _a Eu _b Al _c Si _d O _e N _{f of} the present invention is excited by light in a range of 300 to 500 nm, it diffuses in a light emitting field larger than a wavelength of 700 nm. The reflectance shows absorption other than Eu ²⁺ in the phosphor, that is, absorption that is not accompanied by light emission from the parent crystal. Therefore, it is considered that the higher the average diffuse reflectance at a wavelength of 700 to 800 nm, the less the absorption of luminescence that is not accompanied by the parent crystal, and the better the light extraction efficiency.

On the other hand, unlike the diffuse reflectance at a wavelength of 700 to 800 nm, the diffuse reflectance at the peak fluorescence wavelength also shows a close relationship with the fluorescence characteristics. The diffuse reflectance at the fluorescence peak wavelength is reduced due to crystal defects near Eu ²⁺ in the crystal. And, when there is a defect in the crystal around Eu ^2+, Eu ²⁺ excited electrons are captured so that the emission is suppressed. Therefore, it is considered that the higher the diffuse reflectance at the peak wavelength of fluorescence, the less the emission is suppressed, and the more excellent the light emission efficiency.

The fluorescent system of the present invention Both the average diffuse reflectance at 800 nm and the diffuse reflectance at the peak wavelength of the fluorescence are controlled within the above-mentioned specified range, so that the luminous efficiency is better than that of conventional phosphors.

Diffusion reflectance is related to crystal defects in phosphors, The existence of two-phase, visible-light-absorbing impurities is closely related, and it can be controlled in the above range by reducing these.

The content of the impurity-carbon contained in the phosphor is controlled to be 0.06 wt% or less, and more preferably 0.04 wt% or less. When the carbon content exceeds 0.06 wt%, the average diffuse reflectance at a wavelength of 700 to 800 nm will be significantly reduced, the non-luminous absorption from the parent crystal will increase, and the luminous efficiency tends to decrease. The carbon that can be present as an impurity in the phosphor of the present invention can be considered to be contained in the raw material of the phosphor or mixed in from a container used during firing.

In addition, when a phosphor is manufactured, crystal defects are reduced by performing an annealing treatment and an acid treatment, so that the diffuse reflectance can be improved.

By controlling the composition ratio and diffuse reflectance as described above The fluorescent system of the present invention is excited by light from ultraviolet to near ultraviolet with a wavelength of 300nm to 420nm, and blue having a wavelength of 450nm to 485nm has a peak light emission wavelength, and in particular, 58 Luminous efficiency above%.

<Method for Manufacturing Phosphor>

The method for producing a phosphor of the present invention includes a mixing step of mixing a raw material containing aluminate, and a baking step of the raw material after the baking mixing step. Step; and an annealing step of performing an annealing treatment after the firing step. It is also preferable to further include an acid treatment step after the annealing step.

Mixing step

When the raw material used in the mixing step is a carbonaceous raw material such as strontium carbonate, the carbon derived from the raw material powder is contained by the phosphor in the form of carbon or carbide, which results in a wavelength of 700 to 800 nm. The average diffuse reflectance tends to decrease. Therefore, in particular, the raw materials to be supplied to Sr and / or Ba are limited to such aluminates, whereby the content of impurities-carbon contained in the phosphor can be significantly reduced, and high luminous efficiency can be achieved.

For the combination of better raw materials, strontium aluminate powder can be used. Powder and / or barium aluminate powder, silicon nitride powder and / or silicon oxide powder, aluminum oxide powder and / or aluminum nitride powder, hafnium oxide powder. The blending ratio of these raw materials can be appropriately designed based on the composition ratios a to f.

The raw materials are mixed by a dry mixing method and a method of removing the solvent by wet mixing in an inactive solvent that does not substantially react with each component of the raw material. As the mixing device, for example, a V-type mixer, a swing mixer, a ball mill, and a vibration mill can be used. Moreover, you may add a flux as needed. As the flux, a halide of an alkali metal, a halide of an alkaline earth metal, a halide of Al, or the like can be used.

2.Baking step

After the mixed powder is dried, at least the mixed powder is filled in a container such as a crucible made of boron nitride on a contact surface, in a firing furnace set at a pressure of 1 atmosphere or more, and in an air, argon, or nitrogen environment at a temperature of 1450 ~ Sintered at 1750 ° C. When the firing temperature is lower than 1450 ° C, the compounds do not fully react with each other The second phase is formed or crystallinity is reduced, and the average diffuse reflectance at a wavelength of 700 to 800 nm tends to decrease. On the other hand, when the firing temperature is higher than 1750 ° C, the sintered body is completely made of a sintered body by a reaction through a liquid phase, and crystallinity may be reduced by mechanically pulverizing or the like when the powder is powdered. tendency.

The holding time of the highest temperature in the firing step will also vary depending on the firing temperature, usually 1 to 20 hours.

3. Annealing step

The annealing step is preferably performed using a firing furnace, and the inside of the firing furnace is at least 1 atmosphere and at least 1300 ° C and 1650 ° C. The environment of the annealing step may use one or a mixture of two or more of nitrogen, argon, and hydrogen.

4. Acid treatment steps

In the case of performing the acid treatment step, one or two or more mixed solutions of hydrochloric acid, sulfuric acid, and nitric acid or an acid solution in which the mixed solution is diluted with ion-exchanged water may be used. By performing the acid treatment step, impurities remaining on the surface of the phosphor can be vaporized and removed, and the luminous efficiency can be further improved.

<Light-emitting device>

The light-emitting device of the present invention includes a light-emitting element and the phosphor of the present invention. In addition to the phosphor of the present invention, such a light-emitting device may be used in combination with one or more phosphors having a light emission peak wavelength at a longer wavelength than the phosphor of the present invention.

Compared with the phosphor of the present invention, a phosphor having an emission peak wavelength at a long wavelength means a phosphor having an emission peak in a wavelength range of 485 nm or more. For example, β-SiAlON: Eu, (Ba, Sr) ₂ SiO ₄ : Eu, Sr-SiAlON: Eu, α-SiAlON: Eu, (Li, Ca) (Al, Si) ₂ (N, O) ₃ : Ce, (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu, SrAlSi ₄ N ₇ : Eu, (Ca, Sr) AlSiN ₃ : Eu, La ₂ O ₂ S: Eu. The phosphor that can be used in combination with the phosphor of the present invention is not particularly limited, and can be appropriately selected depending on the brightness, color rendering, and the like required by the light-emitting device.

The light emitting element is preferably an inorganic light emitting element or an organic light emitting element having a light emission of 340 nm to 450 nm. The light emitting element is preferably a laser diode element or an LED element.

The light-emitting device can be used as a backlight for a liquid crystal TV, a light source device for a projector, a lighting device, a traffic light, a road sign, and the like.

[Example]

The present invention will be described in more detail by the following examples. Table 1 shows the composition ratio, diffuse reflectance, carbon content, and luminous efficiency of the phosphors of the respective examples and comparative examples.

<Example 1> 1. Manufacture of phosphor

The phosphor of Example 1 was produced through the following mixing steps, firing steps, and annealing steps.

<Mixing step>

As a raw material of the phosphor, powders of SrAl ₂ O ₄ (strontium aluminate), Si ₃ N ₄ (silicon nitride), Al ₂ O ₃ (alumina), and Eu ₂ O ₃ (hafnium oxide) were used. These were weighed so as to have the composition ratios described in Table 1, and mixed using a V-type mixer (S-3 manufactured by Tsutsui Rika Chemical Co., Ltd.) to prepare a mixed powder.

<Baking step>

The obtained mixed powder was filled into a cylindrical boron nitride container with a lid (N-1 grade manufactured by Denka Kogyo Co., Ltd.). The boron nitride crucible filled with the mixed powder was placed in an electric furnace of a graphite heater heating method using a carbon fiber formed body as a heat insulating material, and the mixed powder was fired. The firing system is to use a rotary pump and a diffusion pump to make the heating frame of the electric furnace vacuum. From room temperature to nitrogen pressure of 1 atmosphere, the temperature is raised from room temperature to 1650 ° C at a rate of 500 ° C per hour and maintained at 1650 ° C for 4 hours. hour. The fired material is pulverized to make the phosphor powdery.

<Annealing step>

The obtained fired product was annealed in a nitrogen atmosphere (atmospheric pressure) at 1500 ° C. for 8 hours to obtain the phosphor of Example 1.

2. Analysis of composition ratio

The composition ratios a to f are obtained by analyzing the obtained phosphor by the following method. That is, cationic elements of Me element, Eu element, Al, and Si, and anions of O and N by ICP emission spectrometry. For the carbon content, use a C / S simultaneous analyzer (CS-444LS) to determine the carbon content.

3. Measurement of diffuse reflectance

The average diffuse reflectance at 700 to 800 nm and the diffuse reflectance at the peak wavelength of fluorescence are based on a device equipped with an integrating sphere device (ISV-469) installed in an ultraviolet-visible spectrophotometer (V-550) manufactured by Japan Spectroscopy Corporation. Determination. Baseline correction was performed with a standard reflection plate [Wavelength Calibration Standard (Spectralon) (registered trademark)], a solid sample holder filled with a phosphor powder sample was placed, and the diffusion reflectance was measured in a wavelength range of 450 to 800 nm.

The average diffuse reflectance at 700 ~ 800nm is the average value of 700nm to 800nm in this measurement result. The diffuse reflectance at the fluorescence peak wavelength is a measurement result at the fluorescence peak wavelength (near 469 nm) among the measurement results.

4. Measurement of Luminous Efficiency

The luminous efficiency of the phosphor was measured by the following method. Using MCPD-7000, manufactured by Otsuka Electronics Co., Ltd., a standard reflection plate (Spectralon, manufactured by Labsphere, Inc.) with a reflectance of 99% was installed in the sample section, and the spectrum of excitation light having a wavelength of 405 nm was measured. At that time, the number of excited photons (Qex) was calculated from the spectrum in the wavelength range of 400 to 415 nm. Next, a phosphor is set in the sample part, and the number of fluorescent photons (Qem) is calculated from the obtained spectral data. The number of fluorescent photons is calculated in the range of 415 to 800 nm. The luminous efficiency (= Qem / Qex × 100) was obtained from the number of obtained photons.

The composition of the phosphor of Example 1 is Ba _0.93 Eu _0.07 Al _1.83 Si _2.75 O _3.28 N _3.12 . The phosphor of Example 1 has a luminous efficiency of 60%, an average diffuse reflectance at a wavelength of 700 to 800 nm of 95%, a diffuse reflectance at a peak fluorescent wavelength of 87%, and a carbon content of 0.04 wt%. Although there is no record in Table 1, the emission peak wavelength is in the range of 469nm ± 8nm.

<Example 2>

Example 2 was manufactured in the same manner as in Example 1 except that the phosphor obtained after the annealing step was put into an acidic solution in which nitric acid was diluted with ion-exchanged water for 30 to 60 minutes. The dilution rate of nitric acid was set to 12% by volume.

The composition of the phosphor of Example 2 was Ba _0.93 Eu _0.07 Al _1.89 Si _2.84 O _3.45 N _3.13 . The luminous efficiency of the fluorescent system of Example 2 was 67%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 96%, the diffuse reflectance at a peak fluorescent wavelength was 93%, and the carbon content was 0.04 wt%. Although there is no record in Table 1, the emission peak wavelength is in the range of 469nm ± 8nm.

<Example 3>

Example 3 was manufactured in the same manner as in Example 2 except that BaAl ₂ O ₄ (barium aluminate) was further blended as a raw material. The composition of the phosphor of Example 3 was (Sr, Ba) _0.93 Eu _0.07 Al _1.83 Si _2.68 O _3.38 N _3.12 , and the composition ratio of Sr and Ba was Sr: Ba = 1.00: 1.24.

The luminous efficiency of the fluorescent system of Example 3 was 62%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 94%, the diffuse reflectance at a peak fluorescent wavelength was 87%, and the carbon content was 0.02 wt%. Although there is no record in Table 1, the emission peak wavelength is in the range of 469nm ± 8nm.

<Example 4>

Example 4 was produced in the same manner as in Example 2 except that BaAl ₂ O ₄ (barium aluminate) was further blended as a raw material. The composition of the phosphor of Example 4 was (Sr, Ba) _0.93 Eu _0.07 Al _2.10 Si _3.84 O _3.95 N _4.22 , and the composition ratio of Sr and Ba was Sr: Ba = 1.00: 1.19.

The luminous efficiency of the fluorescent system of Example 4 was 62%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 94%, the diffuse reflectance at a peak fluorescent wavelength was 88%, and the carbon content was 0.02 wt%. Although there is no record in Table 1, the emission peak wavelength is in the range of 469nm ± 8nm.

<Example 5>

Example 5 was produced in the same manner as in Example 2 except that BaAl ₂ O ₄ (barium aluminate) was used instead of SrAl ₂ O ₄ (strontium aluminate). The composition of the phosphor of Example 5 is Ba _0.96 Eu _0.04 Al _1.93 Si _2.99 O _3.55 N _3.09 .

The luminous efficiency of the fluorescent system of Example 5 is 59%, the average diffuse reflectance at a wavelength of 700 to 800 nm is 95%, the diffuse reflectance at a peak fluorescent wavelength is 93%, and the carbon content is 0.03 wt%. Although there is no record in Table 1, the emission peak wavelength is in the range of 469nm ± 8nm.

<Comparative example 1>

Comparative Example 1 was manufactured in the same manner as in Example 1 except that the annealing treatment was not performed. The composition of the phosphor of Comparative Example 1 was Ba _0.93 Eu _0.07 Al _1.85 Si _2.74 O _3.50 N _3.18 . The luminous efficiency of the fluorescent system of Comparative Example 1 was 49%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 94%, and the diffuse reflectance at a peak fluorescence wavelength was 79%. Although there is no description in Table 1, the emission peak wavelength of the phosphor of Comparative Example 1 is in a range of 469 nm ± 8 nm.

<Comparative example 2>

Comparative Example 2 was produced in the same manner as in Example 2 except that barium carbonate was used instead of SrAl ₂ O ₄ (strontium aluminate). The composition of the phosphor of Comparative Example 2 was Ba _0.93 Eu _0.07 Al _1.90 Si _3.05 O _3.75 N _3.23 . The luminous efficiency of the fluorescent system of Comparative Example 2 was 55%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 87%, the diffuse reflectance at a fluorescent peak wavelength was 84%, and the carbon content was 0.08 wt%.

<Comparative example 3>

Comparative Example 3 was produced in the same manner as in Example 2 except that barium carbonate and strontium carbonate were used instead of SrAl ₂ O ₄ (strontium aluminate). The composition system of the phosphor of Comparative Example 3 was (Sr, Ba) _0.93 Eu _0.07 Al _1.91 Si _2.89 O _3.59 N _3.20 , and the composition ratio of Sr and Ba was Sr: Ba = 1.00: 1.22. The luminous efficiency of the fluorescent system of Comparative Example 3 was 54%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 86%, the diffuse reflectance at a fluorescent peak wavelength was 84%, and the carbon content was 0.10 wt%.

<Comparative Example 4>

Comparative Example 4 was manufactured in the same manner as in Example 2 except that BaAl ₂ O ₄ (barium aluminate) was further blended as a raw material and the composition ratio d of Si was not included in the range defined by the present invention. The composition system of the phosphor of Comparative Example 4 was (Sr, Ba) _0.93 Eu _0.07 Al _1.68 Si _2.49 O _3.60 N _2.77 , and the composition ratio of Sr and Ba was Sr: Ba = 1.00: 2.55. The luminous efficiency of the fluorescent system of Comparative Example 4 was 48%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 83%, and the diffuse reflectance at a peak fluorescent wavelength was 79%.

<Comparative example 5>

Comparative Example 5 was the same as in Example except that BaAl ₂ O ₄ (barium aluminate) was further blended as a raw material and the composition ratios b, c, and e of Eu, Al, and O were not included in the range specified by the present invention. Manufacturing at 2 locations. The composition system of the phosphor of Comparative Example 5 was (Sr, Ba) _0.78 Eu _0.22 Al _2.52 Si _2.99 O _4.91 N _3.10 , and the composition ratio of Sr and Ba was Sr: Ba = 1.00: 2.45. The luminous efficiency of the fluorescent system of Comparative Example 5 was 43%, the average diffuse reflectance at a wavelength of 700 to 800 nm was 80%, and the diffuse reflectance at a peak fluorescence wavelength was 77%.

Fig. 1 shows the fluorescence of Examples 1 and 2 and Comparative Examples 1 and 2. Volume diffuse reflectance spectrum. It was confirmed that Example 2 was subjected to acid treatment through transmission, and the diffuse reflectance was higher than that of Example 1. In Comparative Example 1, it is understood that the diffuse reflectance is lower than that in Example 1 because the annealing treatment is not performed, and the diffuse reflectance in the vicinity of the peak wavelength is significantly reduced. In Comparative Example 2, it is understood that the use of carbonate as a raw material increases the carbon content, and in particular, the average diffuse reflectance at a wavelength of 700 to 800 nm is significantly reduced.

<Example 6>

A light-emitting member was produced using the phosphor of Example 1 mixed with a sealing material and a light-emitting diode as a light-emitting element. This light-emitting member exhibits higher brightness than a light-emitting member manufactured in the same manner using the phosphor of Comparative Example 1 or 2.

Moreover, as a result of manufacturing a light-emitting device using this light-emitting member, it is possible to achieve higher brightness than in the past.

Claims (5)

A phosphor is represented by the general formula: Me _a Eu _b Al _c Si _d O _e N _f , and the composition ratios a, b, c, d, e, and f are, a + b = 1, 0.01 <b < 0.20, 1.65 <c <2.50, 2.50 <d <4.00, 3.15 <e <4.90, and 2.80 <f <4.30, Me is either or both of Sr and Ba, and when excited by near-ultraviolet or purple light, The peak blue light emission is performed in a wavelength range of 450 to 485 nm. The average diffuse reflectance at a wavelength of 700 to 800 nm is 90% or more, and the diffuse reflectance at a fluorescent peak wavelength is 85% or more. For example, the phosphor of claim 1, wherein the carbon content is 0.06 wt% or less. A light-emitting device includes a phosphor and a light-emitting light source as claimed in claim 1 or 2. A method for manufacturing a phosphor, which is a method for manufacturing a phosphor as claimed in claim 1 or 2, comprising a mixing step of mixing raw materials, a baking step of raw materials after the baking mixing step, and The fired product after the firing step is an annealing step of annealing treatment, wherein the raw material for supplying Sr and / or Ba in the mixing step is such an aluminate. The method for manufacturing a phosphor as claimed in claim 4, further comprising an acid treatment step after the annealing step.