JP2007039591A - Phosphor and method for producing the same and light emitting device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phosphor excellent in luminous characteristics and durability and to provide a method for producing the phosphor by which mass production is facilitated and to provide a light emitting device including white LED illumination using the phosphor and to provide a phosphor film for excitation of electron beam and electron beam-excited color display device each using the phosphor. <P>SOLUTION: The phosphor comprises ≥0.10 ppm and ≤10,000 ppm metal element(s) constituting a compound represented by the composition formula: Si<SB>6-x</SB>Al<SB>x</SB>O<SB>x</SB>N<SB>8-x</SB>:Z (Z element acts as an activating agent in the phosphor) and sublimating or evaporating at 1,000°C to 1,800°C. The metal element(s) constituting the compound is preferably one or more elements selected from zinc (Zn), gallium (Ga), indium (In), thallium(Tl), germanium (Ge), tin (Sn), lead (Pb) and manganese (Mn). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes a display such as a cathode ray tube (CRT), a field emission display (FED), a plasma display (PDP), a semiconductor light emitting element (hereinafter sometimes referred to as LED), a fluorescent lamp, a fluorescent display tube, and the like. Nitrogen-containing phosphors used in lighting devices and light-emitting appliances such as liquid crystal backlights and methods for producing the same, and white LED lighting in which the phosphors are combined with, for example, semiconductor light-emitting elements (LEDs) The present invention relates to a light emitting device, a phosphor film for electron beam excitation using the phosphor, and an electron beam excited color display device.

  At present, discharge-type fluorescent lamps and incandescent bulbs mainly used as lighting devices have various problems such as containing harmful substances such as mercury and short life. However, in recent years, high-intensity LEDs that emit light in the near ultraviolet / ultraviolet to blue have been developed one after another, and from near ultraviolet / ultraviolet to blue light generated from the LEDs and phosphors having an excitation band in the wavelength region. Research and development are actively conducted on whether white light can be produced by mixing the generated light with the white light and used as next-generation lighting. If this white LED lighting is put to practical use, it will not break like a conventional incandescent light bulb because it has high efficiency in converting electrical energy into light and generates less heat, and it is composed of LEDs and phosphors. There are advantages that it has a long life, does not contain harmful substances such as mercury, and that the lighting device can be miniaturized, and an ideal lighting device can be obtained.

The light emitting device composed of the LED and the phosphor is called a one-chip type, and the blue LED and the yellow phosphor (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce (YAG: Ce), Tb ₃ A combination of Al ₅ O ₁₂ : Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce), and a combination of near-ultraviolet / ultraviolet LEDs and red, green, and blue phosphors are typical. There is already practical application. The one-chip type can obtain white light with excellent color rendering properties compared to the multi-chip type, the drive circuit can be simplified and miniaturized, no light guide for mixing colors is required, the driving voltage and light of each LED There are many advantages such as low cost without considering the difference in output and temperature characteristics.

  As in the case of a light emitting device such as a normal fluorescent lamp, even in the case of a light emitting device composed of the LED and a phosphor, an efficient device with low power consumption and high luminance is required. In order to increase the efficiency of the device itself, it is necessary to increase the light extraction efficiency from the semiconductor element that is the excitation source, and to obtain a phosphor that efficiently converts the light that serves as the excitation source into light of a different wavelength. There is a need for a phosphor that emits light efficiently from near-ultraviolet / ultraviolet to blue light emission, which is the emission wavelength of LEDs that are widely used as a light source.

For this reason, research on efficient phosphors has been actively conducted, and along with further improvements of conventional oxide, sulfide, and phosphate phosphors, Ca ₂ Si ₅ N ₈ : Eu, Nitride phosphors such as Sr ₂ Si ₅ N ₈ : Eu, Ba ₂ Si ₅ N ₈ : Eu, CaSrSi ₅ N ₈ : Eu, Sr ₂ Si ₅ N ₈ : Ce (see Patent Documents 1 and 2), Sr ₂ A phosphor having a new composition has been developed one after another, such as an oxynitride phosphor such as Si ₃ Al ₂ N ₈ O ₂ : Eu (see Patent Document 3). Recently, as shown in Non-Patent Document 1, β-SIALON phosphors have been developed as oxynitride phosphors that emit green light, and various phosphors are obtained from green to red. These nitrogen-containing phosphors are characterized by excellent temperature characteristics and durability, and are being used in light-emitting devices such as white LED lighting.

Special table 2003-515655 JP 2004-244560 A International Publication No. 2004/055910 A1 Pamphlet 2005 Spring 52nd Joint Lecture on Applied Physics Lecture Proceedings p1615 (30a-YH-7)

  Some of the phosphors containing nitrogen described above are excellent in durability against heat and water, but on the other hand, the luminous efficiency when excited by near ultraviolet / ultraviolet to blue excitation light is satisfied. It is not at the power level, and sufficient light emission intensity and luminance are not obtained. Therefore, the brightness, which is the most important element for the light emitting device, is insufficient. In particular, a phosphor having a peak wavelength of the emission spectrum in the range of 500 nm to 600 nm directly affects the luminance of the light emitting device, so that a more satisfactory light emitting characteristic and durability are required.

  Although the β-SiAlON phosphor shown in Non-Patent Document 1 has good luminous efficiency, it is manufactured by a manufacturing method under a firing temperature of 1900 ° C. and a furnace pressure of 1 MPa. Manufacturing equipment was needed. Furthermore, in the case of industrial production, it was difficult to improve productivity.

  An object of the present invention has been made in consideration of the above-mentioned problems, and is a phosphor excellent in light emission characteristics and durability, and easy to mass-produce, a method for manufacturing the same, and the phosphor It is an object of the present invention to provide a light emitting device such as white LED illumination using a phosphor, a phosphor film for electron beam excitation using the phosphor, and an electron beam excitation color display device.

In order to solve the above-described problems, the present inventors have conducted research on phosphor compositions and production methods containing various types of nitrogen, and as a result, added compounds that sublimate or evaporate at a temperature of 1000 ° C. to 1800 ° C. And represented by the composition formula Si _6-x Al _x O _x N _8-x : Z (the Z element is an element that acts as an activator in the nitride phosphor or oxynitride phosphor). New nitrogen-containing phosphors that have satisfactory luminous efficiency when excited by near-ultraviolet / ultraviolet to blue excitation light and have excellent durability against heat and water. The present invention has been completed by conceiving that the novel phosphor can be produced by an easy and inexpensive production method.

The first configuration for solving the above-described problem is as follows.
A production phase represented by a composition formula Si _6-x Al _x O _x N _8-x : Z (wherein the Z element is an element acting as an activator in the phosphor), and 1000 ° C. to 1800 A metal element constituting a compound that sublimes or evaporates at a temperature of ° C.,
A phosphor containing 0.10 ppm or more and 10000 ppm or less of a metal element constituting a compound that sublimes or evaporates at a temperature of 1000 ° C. to 1800 ° C.

The second configuration is the phosphor described in the first configuration,
The metal element constituting the compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. is zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin (Sn) A phosphor characterized by being one or more elements selected from lead (Pb) and manganese (Mn).

A third configuration is the phosphor according to the first or second configuration,
The phosphor is characterized by 0.3 ≦ x ≦ 0.9.

A fourth configuration is the phosphor according to any one of the first to third configurations,
The phosphor is characterized in that the Z element is one or more elements selected from Eu, Ce, Pr, Tb, Yb, and Mn.

A fifth configuration is the phosphor according to any one of the first to fourth configurations,
The phosphor is characterized in that a crystal system of a generation phase of the phosphor is a hexagonal crystal.

A sixth configuration is the phosphor according to any one of the first to fifth configurations,
A phosphor having a crystallite size (Dx) of a generation phase of the phosphor of 50 nm or more.

A seventh configuration is the phosphor according to any one of the first to sixth configurations,
The phosphor is in the form of powder.

An eighth configuration is the phosphor according to the seventh configuration,
The phosphor has an average particle diameter (D50) of 0.5 μm or more and 50.0 μm or less.

A ninth configuration is a method of manufacturing a phosphor according to any one of the first configuration to the eighth configuration,
Mixing the raw materials of the phosphor to obtain a mixture;
Installing the mixture in a firing furnace and heating to form a fired product;
Crushing the fired product to obtain a phosphor,
As a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C., zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin (Sn), lead (Pb) A method for producing a phosphor, comprising adding one or more compounds selected from oxides of manganese (Mn) to the mixture.

A tenth configuration is a method for manufacturing the phosphor according to the ninth configuration,
The mixture is placed in a BN crucible in powder form and placed in a firing furnace,
The atmosphere gas in the firing furnace is a gas containing at least one selected from nitrogen gas, rare gas, and ammonia gas, and the selected gas is circulated in the firing furnace at a rate of 0.1 ml / min or more. However, it is a method for producing a phosphor, characterized by heating at a temperature of 1400 ° C. or higher and 1800 ° C. or lower.

The eleventh configuration is a method for manufacturing the phosphor according to the ninth or tenth configuration,
In the phosphor manufacturing method, an internal pressure in the firing furnace is set to 0.001 MPa or more and 0.5 MPa or less.

  A twelfth configuration includes the phosphor according to any one of the first to eighth configurations, a light emitting unit that emits light of a first wavelength, and a part or all of the first wavelength It is a light-emitting device that emits a wavelength different from the first wavelength from the phosphor as excitation light.

A thirteenth configuration is the light emitting device according to the twelfth configuration,
The first wavelength is a light emitting device having a wavelength of 350 nm to 500 nm.

A fourteenth configuration is the light emitting device according to the twelfth or thirteenth configuration,
The light emitting device is characterized in that an average color rendering index Ra is 80 or more.

A fifteenth configuration is the light emitting device according to any one of the twelfth to fourteenth configurations,
The light emitting device is characterized in that the special color rendering index R15 is 80 or more.

A sixteenth configuration is the light emitting device according to any one of the twelfth to fifteenth configurations,
The light emitting device is characterized in that the special color rendering index R9 is 60 or more.

A seventeenth configuration is the light emitting device according to any one of the twelfth to sixteenth configurations,
The light emitting device is characterized in that the correlated color temperature is in the range of 7000 K to 2500 K.

An eighteenth configuration is the light emitting device according to any one of the twelfth to seventeenth configurations,
In the light-emitting device, the light-emitting unit that emits the first wavelength is an LED.

  A nineteenth configuration is a phosphor film for electron beam excitation manufactured using the phosphor according to any one of the first to eighth configurations.

  A twentieth configuration is an electron beam excitation color display device manufactured using the phosphor according to any one of the first to eighth configurations.

  The phosphor according to any one of the first to eighth configurations has a flat excitation band in the near-ultraviolet / ultraviolet to blue range, the emission spectrum has a broad peak, and has excellent emission efficiency and luminance. It is a phosphor (the peak wavelength of the emission spectrum is around 500 nm to 600 nm) and has excellent durability against heat and water.

  According to the method for manufacturing a phosphor according to any one of the ninth to eleventh configurations, the phosphor containing nitrogen so far can be added by adding a compound that sublimes or evaporates at a temperature of 1000 ° C. to 1800 ° C. As compared with the above, it becomes possible to synthesize a desired phosphor at a low firing temperature and a low pressure in the furnace, and the phosphor can be easily produced at a low production cost.

  According to the light emitting device according to any one of the twelfth to eighteenth configurations, a highly efficient light emitting device having a desired emission color and high emission intensity and luminance can be obtained.

  According to the light emitting device of the nineteenth or twentieth configuration, the phosphor of the present invention exhibits excellent light emission characteristics even when excited with an electron beam. A color display device can be obtained.

Hereinafter, although embodiment of this invention is described, this invention is not limited to these.
The phosphor of the present embodiment is a nitride phosphor or an oxynitride phosphor including a β-SiAlON phosphor represented by a composition formula Si _6-x Al _x O _x N _8-x : Z. Conventionally, these phosphors have been required to be fired at high temperature and high pressure during synthesis. The Z element is an element that acts as an activator in the phosphor, and is one or more elements selected from rare earth elements or transition metal elements. Further, in the phosphor, when x is in the range of 0.2 ≦ x ≦ 2.0, more preferably in the range of 0.3 ≦ x ≦ 0.9, the phosphor is excellent in emission intensity, luminance, durability, and the like.

The phosphor of composition formula Si _6-x Al _x O _x N _8-x : Z having the characteristics described above has a broad emission spectrum in the wavelength range of 500 nm to 600 nm, The phosphor has a flat excitation band over a wide range of blue (wavelength: 250 nm to 500 nm), and high-efficiency light emission can be obtained, and a phosphor excellent in durability against heat and water can be obtained. Therefore, the phosphor and an appropriate other color phosphor are mixed to form a phosphor mixture, and the phosphor mixture is combined with a light emitting unit such as a near ultraviolet / ultraviolet LED or a blue LED to obtain emission intensity and A light emitting device with high luminance can be obtained.

  Further, the phosphor of the present embodiment contains 0.10 ppm or more and 10000 ppm or less, more preferably 0.10 ppm or more and 100 ppm or less, of a metal element constituting a compound that sublimes or evaporates at a temperature of 1000 ° C. to 1800 ° C. ing. This is a result of adding a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. to the phosphor raw material of the present embodiment in the phosphor manufacturing method of the present embodiment described later. Since the sublimation or evaporation temperature of the added compound is in the range of 1000 ° C. to 1800 ° C., most of these compounds are volatilized from the phosphor raw material in the firing process. Slightly incorporated into the host structure of the phosphor, the metal elements constituting the compound remain in the production phase of the phosphor of the present embodiment at 0.10 ppm or more and 10,000 ppm or less. If the remaining metal element is 0.10 ppm or more, the effect of promoting the formation of the β-SiAlON structure is sufficiently obtained by the liquid phase generation effect of the additive, and a phosphor having excellent light emission characteristics can be obtained. On the other hand, if the residual metal element is 10000 ppm or less, more preferably 100 ppm or less, Eu can be dissolved in the β-SiAlON structure without deteriorating the light emission characteristics due to the residue. Thus, a β-SiAlON phosphor having excellent emission characteristics that emits green light can be obtained.

  Typical compounds that satisfy the above conditions are those that sublime or evaporate at a temperature of 1000 ° C to 1800 ° C. Zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin Nitride, fluoride, chloride, sulfide, phosphide, oxide, carbonate, oxalate, nitrate, hydroxide, water content (Sn), lead (Pb), manganese (Mn) A hydroxide, an oxyhydroxide, etc. can be mentioned, Preferably the said metal element oxide is preferable. Among these, ZnO which is a Zn oxide is more preferable. The compound to be added is not a problem as long as it sublimates or evaporates, but it is preferable to avoid a compound containing Fe that is generally known as a killer element of the phosphor.

Next, the light emission characteristics of the phosphor according to this embodiment will be described.
First, by using the phosphor according to the present embodiment, light emission with high color rendering properties can be obtained. Here, the color rendering property means that the appearance of the color of an object irradiated with light from a light source changes depending on the type of the light source. The color rendering property indicating the color reproducibility of the illuminated object depending on the type of the light source can generally be expressed numerically by an average color rendering index (Ra). If the exact same color as that seen with the reference light can be reproduced, the best average color rendering index (Ra = 100) is obtained, and the Ra value decreases (Ra <100) as the difference in the reproduced color increases.

  Of course, as a light source for illumination, it is preferable that the color appearance is the same as when using the reference light, but the reference light is a white light source having uniform light over the entire visible light, The white LED lighting has uneven light intensity such that the light intensity is high at a certain wavelength in the visible light region and low at a certain wavelength, so that the color reproducibility is low in the wavelength region where the light intensity is insufficient. Color rendering properties deteriorate. In particular, white LED lighting combining a blue LED and a yellow phosphor has a problem in that light of red and green components is insufficient because white is synthesized by mixing blue and yellow light.

  After all, in order to obtain light emission with high color rendering properties, the phosphor used in white LED lighting has a broad peak in the emission spectrum, and the phosphor can cover all the light in the visible light range without any unevenness. It is necessary to align. The emission spectrum of the phosphor according to the present embodiment is broad in a wide wavelength range from 470 nm to 650 nm, and is a phosphor having a peak in the range of 500 nm to 600 nm. It is promising as a fluorescent material. In particular, when the phosphor is added to a current product that combines a blue LED and a yellow phosphor, it can compensate for the light of the green component that has been lacking so far, and can provide an excellent color rendering property.

  The phosphor of this embodiment has an excitation band with high efficiency over a wide range of wavelengths from 250 nm to 500 nm, and in particular, has an excitation peak in the wavelength range of 270 nm to 330 nm and exhibits the highest emission efficiency. . That is, the phosphor of the present embodiment can produce high-intensity white LED illumination by combining with near ultraviolet / ultraviolet to blue excitation light used for white LED illumination. In addition, since there is a wide range of highly efficient excitation bands, as in the case of YAG: Ce phosphors, if the excitation light deviates even slightly from the optimum excitation band range, the balance between the blue and yellow emission intensities is lost. The problem that the color tone of white light changes can be suppressed.

The phosphor of the present embodiment has a broad peak of the emission spectrum in the range from green to yellow (wavelength 500 nm to 600 nm), and over a wide range from near ultraviolet / ultraviolet to blue (wavelength 250 nm to 500 nm). It has a flat excitation band, provides high-efficiency light emission, has excellent durability against heat and water, and has excellent temperature characteristics particularly at high temperatures. Although the detailed reason is unknown, it is generally considered as follows. First, the composition formula Si _6-x Al _x O _x N _8-x : Z of the phosphor of the present embodiment is such that x in the range of 0.3 ≤ x ≤ 0.9 takes a β-SiAlON structure and activates it. It is considered that the luminous efficiency can be improved because the agent can exist regularly in the structure and the excitation energy used for light emission is efficiently transmitted. In addition, it has a wide excitation band from the near ultraviolet / ultraviolet to the blue (wavelength 250 nm to 500 nm) visible region on the long wavelength side because it contains nitrogen compared to oxide phosphors. The reason is that the covalent bond is strong.

Furthermore, since x of the phosphor is in the range of 0.3 ≦ x ≦ 0.9, a chemically stable composition is obtained, so that an impurity phase is hardly generated in the phosphor, and a decrease in emission intensity is suppressed. It is thought that. In particular, when x of the phosphor is in a range of 0.3 ≦ x ≦ 0.9, it is difficult to generate a cubic α-phase as an impurity phase in addition to a hexagonal β-phase. When this α phase is generated, it becomes a phosphor emitting yellow light instead of aiming green light. In other words, when not only the α phase but also a large amount of impurity phase occurs, the amount of phosphor with the desired emission characteristics per unit area decreases, and the generated impurity phase is generated from excitation light or phosphor. It is considered that the light emission efficiency of the phosphor is reduced by absorbing the emitted light, and a high light emission intensity cannot be obtained.
When x is 0.3 ≦ x ≦ 0.9, the concentration of Al element contained in the phosphor is 2.8 wt% or more and 8.6 wt% or less.

The inference is that, in the X-ray diffraction measurement for the phosphor according to the present embodiment after firing, when the value of x is within the above-mentioned range, the impurity phase peaks of unreacted raw materials such as AlN and Si ₃ N ₄ , and The peak of the impurity phase different from the phase contributing to the intended light emission is not confirmed, or even when confirmed, the diffraction intensity is very low, whereas when the value of x is outside the above range, AlN, This is also supported by the fact that significant peaks of Si ₃ N ₄ and a phase different from the phase contributing to light emission are confirmed. The feature that the peak of the impurity phase is not observed in the X-ray diffraction pattern for the phosphor after firing is that the phosphor to be measured has the intended emission characteristics and high emission intensity. It is thought that it is showing.

In the composition formula Si _6-x Al _x O _x N _8-x : Z, the Z element is one or more elements selected from rare earth elements or transition metal elements, and it is still unknown which site is the activator. Although it is not, it is thought that it regularly enters the matrix structure.
From the viewpoint of causing various light sources such as white LED illumination using the phosphor of this embodiment to exhibit sufficient color rendering properties, it is preferable that the half width of the peak in the emission spectrum of the phosphor is wide. From this viewpoint, it is considered that the Z element is preferably one or more elements selected from Eu, Ce, Pr, Tb, Yb, and Mn. In particular, when Eu is used as the Z element, the phosphor exhibits a broad emission spectrum with a high emission intensity from green to yellow, and thus is preferable as an activator for various light sources including white LED illumination.

  Moreover, by selecting the Z element, the peak wavelength of light emission in the phosphor of the present embodiment can be made variable, and by activating different types of Z elements, the peak wavelength can be made variable, Due to the sensitizing action, it is possible to improve the light emission intensity and the luminance. For example, when Ce is activated instead of Eu, a phosphor having an emission spectrum peak near 475 nm with excitation light of 405 nm can be obtained.

The amount of addition of the Z element is as follows when the phosphor of the present embodiment is expressed as Si _6-x-z Al _x O _x N _8-x : Z _z (when the Z element substitutes a part of the Si element) The amount of addition may be determined so that the value of z / (6-x), which is the molar ratio between the Si element and the Z element, is in the range of 0.0001 or more and 0.50 or less. preferable. If the amount of Z element added is within the above range, concentration quenching can occur due to excessive activator (Z element) content, thereby preventing a decrease in luminous efficiency, It is also possible to avoid a decrease in luminous efficiency due to a shortage of light emission contributing atoms due to an insufficient activator (Z element) content. Furthermore, it is more preferable if the value of z / (6-x) is in the range of 0.0001 or more and 0.10 or less. However, the optimum value of the range of the addition amount of the Z element slightly varies depending on the type and composition formula of the activator (Z element) and the matrix structure. Furthermore, by controlling the addition amount of the activator (Z element), the peak wavelength of light emission of the phosphor can be shifted, which is effective in adjusting the luminance and color rendering properties of the obtained light source.

  Further, the crystallite size of the generation phase of the phosphor of the present embodiment is preferably as large as possible. This is because the larger the crystallite size, the more uniformly the phase contributing to light emission is obtained, and the more uniform product phase is obtained. If the crystallite size is 10 nm or less, the phase becomes close to an amorphous phase, and an impurity phase that does not contribute to light emission. Therefore, considering from the viewpoint of the luminous efficiency of the phosphor, it is possible to avoid a decrease in the luminous efficiency when the crystallite size of the phosphor is 10 nm or more, and preferably 50 nm or more. The crystallite size is an average value obtained by calculating the half width B of each diffraction peak in the powder X-ray diffraction measurement of the phosphor of the present embodiment and using the half width B from the Scherrer equation. It is.

  By making the phosphor of the present embodiment into a powder form, it can be easily applied to various light emitting devices such as white LED illumination. Here, when the phosphor is used in the form of powder, the phosphor includes primary particles of 50.0 μm or less and aggregates of the primary particles, and the phosphor powder including the primary particles and aggregates. The average particle diameter (D50) is 0.5 μm or more and 50.0 μm or less, more preferably 1.0 μm or more and 15 μm or less. This is because if the average particle size is 50.0 μm or less, the subsequent pulverization can be easily performed, and the phosphor powder is considered to emit light mainly on the particle surface, so the average particle size is 50.0 μm or less. If this is the case, the surface area per unit weight of the powder can be ensured and the decrease in luminance can be avoided. Further, the density of the powder can be reduced even when the powder is made into a paste and applied to a light emitting device or the like. This is because a reduction in luminance can be avoided also from this viewpoint. Further, according to the study by the present inventors, although the detailed reason is unknown, it has been found that the average particle size is preferably larger than 0.5 μm from the viewpoint of the luminous efficiency of the phosphor powder. From the above, the average particle size of the powder in the phosphor of the present embodiment is preferably 0.5 μm or more and 50.0 μm or less. The average particle diameter (D50) here is a value measured by LS230 (laser diffraction scattering method) manufactured by Beckman Coulter.

  Further, as described above, in this embodiment, a compound is added so that sublimation or evaporation proceeds simultaneously at a temperature of 1000 ° C. to 1800 ° C. Here, when the temperature at which the compound sublimates or evaporates is too low, the added compound is volatilized before the temperature is sufficiently raised in the firing step, so that the effect as a reaction accelerator cannot be sufficiently exerted. . Also, if the temperature at which sublimation or evaporation is too high, it remains in the solid phase during firing and does not function as a reaction accelerator, or it functions as a reaction accelerator by forming a liquid phase This is because there is a high possibility that the phosphor is vitrified after firing.

  In addition, in the phosphor after firing, the metal elements constituting the added compound are zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin (Sn) , Lead (Pb), manganese (Mn) and the like are preferably contained in an amount of 0.10 ppm to 10000 ppm. More preferably, it is 0.10 ppm or more and 100 ppm or less. As described above, if the residual metal element is 0.10 ppm or more, the residual element is sufficiently effective in promoting the reaction of β-SiAlON structure generation by the liquid phase generation of the additive, and has excellent emission characteristics. If it is 10000 ppm or less, more preferably 100 ppm or less, Eu can be dissolved in the β-SiAlON structure without deteriorating the light emission characteristics due to the residual, and green. It is possible to obtain a β-SiAlON phosphor having excellent light emission characteristics.

On the other hand, the raw material of the β-SiAlON phosphor represented by the composition formula Si _6-x Al _x O _x N _8-x : Z is baked without adding a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. As a result, the intended hexagonal β-phase cannot be obtained as a single phase, and a cubic α-phase that is considered stable at low temperatures is generated. When this α phase is generated, Eu of the activator used in the embodiment does not enter the β phase, enters the α phase, and forms α-SiAlON. Without yellow light emission. Therefore, in order to obtain only the hexagonal β-phase, which is considered stable at high temperatures, when the firing temperature is higher than 1800 ° C, N is released from the raw material Si ₃ N ₄ and metal Si is formed in the sample. As a result, β-SiAlON phosphor cannot be obtained. In order to prevent N from escaping from Si ₃ N ₄ , the furnace pressure may be increased to about 1.0 Mpa. However, from the viewpoint of productivity and equipment, it is not suitable for mass production of phosphors and the production cost is high. turn into.

  From the above, this embodiment of adding a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. during the firing of the phosphor material suppresses the generation of the α phase that is an impurity phase, and generates only the β phase What you can do. The metal element that constitutes the above compound in the β-SiAlON structure, such as Zn, is slightly dissolved, so that the reaction of Eu as an activator in the β-SiAlON structure can be promoted. Furthermore, it is possible to easily and inexpensively produce a novel β-SiAlON phosphor excellent in characteristics without requiring a special baking apparatus with high pressure resistance.

  Next, the phosphor and a light emitting unit that emits light of the first wavelength, and a part or all of the light of the first wavelength is used as excitation light, and the first wavelength from the phosphor A light-emitting device that emits light of different wavelengths will be described.

  As the light emitting unit that emits light of the first wavelength, for example, an LED light emitting element that emits light in the range of near ultraviolet / ultraviolet to blue or a discharge lamp that generates ultraviolet light can be used. When the phosphor mixture containing the phosphor of the present embodiment is combined with the LED light emitting element, various lighting units, backlights for display devices, and the like can be manufactured. When the phosphor mixture is combined with the discharge lamp, various fluorescent lamps, illumination units, backlights for display devices, and the like can be produced.

  Since the phosphor of this embodiment is a nitride or oxynitride and has excellent temperature characteristics, even when the temperature of the light emitting device rises due to use for a long time, a phosphor that hardly causes a color shift. It can be produced. In addition, the emission spectrum has a peak in the range from green to yellow and the peak shape is broad, so it is suitable as a phosphor for white LED illumination from the viewpoint of improving color rendering. In addition, the excitation band has a flat excitation band in the wide range of near ultraviolet / ultraviolet to blue (wavelength range 250 to 500 nm), so, for example, a high-intensity blue LED proposed for white LED illumination (wavelength near 460 nm) In the case of white LED lighting that obtains white by using the complementary color relationship between the blue light emission and the yellow light emission of the phosphor, or the LED that emits near-ultraviolet / ultraviolet light and the near-ultraviolet / Light obtained from other R, G, B phosphors by combining phosphors that emit red (R) light when excited by ultraviolet light, phosphors that emit green (G), and phosphors that emit blue (B) light In the case of a white LED illumination system that obtains white color using the mixed colors, it can be used while exhibiting a state close to the highest light emission intensity. That is, by combining the phosphor with a light emitting part that emits near-ultraviolet / ultraviolet to blue light, a white light source and white LED illumination with high output and good color rendering can be obtained, and an illumination unit using these can be obtained. .

The method of combining the phosphor mixture of the embodiment and the light emitting unit may be performed by a known method, but in the case of a light emitting device using an LED for the light emitting unit, the light emitting device is manufactured as follows. I can do it. Hereinafter, a light-emitting device using LEDs in a light-emitting unit will be described with reference to the drawings.
FIGS. 8A to 8C are schematic cross-sectional views of a bullet-type LED light-emitting device, and FIGS. 9A to 9E are schematic cross-sectional views of a reflective LED light-emitting device. In addition, in each drawing, the same code | symbol is attached | subjected about the corresponding part and description may be abbreviate | omitted.

First, with reference to FIG. 8A, an example of a light-emitting device using an LED as a light-emitting portion and combined with the phosphor mixture will be described. In the bullet-type LED light emitting device, the LED light emitting element 2 is installed in a cup-shaped container 5 provided at the tip of the lead frame 3, and these are molded with a translucent resin 4. In this embodiment, the phosphor mixture or a mixture in which the phosphor mixture is dispersed in a light-transmitting resin such as silicon or epoxy (hereinafter referred to as the mixture 1) is contained in the cup-shaped container 5. Is embedded in all of the above.
Next, an example of a different light-emitting device will be described with reference to FIG. In this embodiment, the mixture 1 is applied on the cup-shaped container 5 and the upper surface of the LED light emitting element 2.
Next, another example of a light-emitting device will be described with reference to FIG. In this embodiment, the phosphor mixture 1 is installed on the LED light emitting element 2.

  As described above, in the bullet-type LED light emitting device described with reference to FIGS. 8A to 8C, the light emission direction from the LED light emitting element 2 is upward, but the same is true even when the light emission direction is downward. The light emitting device can be created by the method. For example, a reflective LED light-emitting device is provided with a reflecting surface and a reflecting plate in the light emitting direction of the LED light-emitting element 2, and the light emitted from the light-emitting element 2 is reflected on the reflecting surface and emitted to the outside. . 9A to 9E, an example of a light emitting device in which the reflective LED light emitting device and the phosphor mixture of the present embodiment are combined will be described.

First, with reference to FIG. 9A, an example of a light-emitting device using a reflective LED light-emitting device as a light-emitting portion and combined with the phosphor mixture of this embodiment will be described. In the reflective LED light-emitting device, an LED light-emitting element 2 is installed at the tip of one lead frame 3, and light emitted from the LED light-emitting element 2 is reflected downward by the reflecting surface 8 and emitted from above. In this embodiment, the mixture 1 is applied onto the reflecting surface 8. The concave portion formed by the reflecting surface 8 may be filled with a transparent molding material 9 to protect the LED light emitting element 2.
Next, an example of a different light-emitting device will be described with reference to FIG. In this embodiment, the mixture 1 is installed under the LED light emitting element 2.
Next, an example of a different light-emitting device will be described with reference to FIG. In this embodiment, the mixture 1 is filled in the recess formed by the reflecting surface 8.
Next, an example of a different light-emitting device will be described with reference to FIG. In this embodiment, the mixture 1 is applied on the transparent mold material 9 for protecting the LED light emitting element 2.
Next, an example of a different light-emitting device will be described with reference to FIG. In this embodiment, the mixture 1 is applied to the surface of the LED light emitting element 2.
The bullet-type LED light-emitting device and the reflection-type LED light-emitting device may be properly used depending on the application, but the reflective LED light-emitting device can be made thin, the light emission area can be increased, and the light utilization efficiency can be increased. There are merits such as.

  When the light-emitting device described above is used as a light source for high color rendering illumination, it is necessary to have an emission spectrum with excellent color rendering properties. Therefore, the present embodiment uses the evaluation method of JIS Z 8726. The color rendering properties of a light emitting device incorporating a phosphor mixture containing the above phosphors were evaluated. In the evaluation of JIS Z 8726, if the average color rendering index Ra of the light source is 80 or more, it can be said to be an excellent light emitting device. Preferably, if the special color rendering index R15, which is an index indicating the skin color component of a Japanese woman, is 80 or more and the special color rendering index R9 is 60 or more, it can be said to be a very excellent light emitting device. However, the above-mentioned index may not be satisfied depending on the use for which color rendering is not required or a different purpose.

  Accordingly, a light emitting device was produced in which light from the light emitting portion emitting light in the wavelength range of 250 nm to 500 nm was irradiated to the phosphor mixture containing the phosphor of this embodiment, and the phosphor mixture emitted light. As the light emitting part, an ultraviolet LED emitting light having a wavelength of 405 nm was used. Then, the emission spectrum and color rendering properties of the light emitting device were evaluated. As a result, the light emission characteristics of the light emitting device incorporating the phosphor mixture containing the phosphor of the present embodiment has three peaks by selecting the phosphor of the present embodiment and the phosphor emitting red and blue. Can have a spectrum. For this reason, in the correlated color temperature range of 7000K to 2500K, Ra is 80 or more, R15 is 80 or more, and R9 is 60 or more, and the light emitting device has high luminance and color rendering. It turned out to be an excellent light source.

  Further, since the phosphor of the present embodiment exhibits emission characteristics even by electron beam excitation, it is promising as a phosphor for electron beam excited color display devices such as cathode ray tubes (CRT) and field emission displays (FED). .

Next, an example of a method for manufacturing the β-SiAlON phosphor according to the present embodiment will be described.
In general, many phosphors are produced by a solid-phase reaction, and the method for producing the phosphor of this embodiment can also be obtained by a solid-phase reaction. Each raw material of Si element and Al element may be a commercially available raw material such as nitride, oxide, carbonate, hydroxide, basic carbonate, but preferably has a purity of 2N or more because higher purity is preferable. More preferably, 3N or more is prepared. In general, the particle diameter of each raw material particle is preferably a fine particle from the viewpoint of promoting the reaction, but the particle diameter and shape of the phosphor to be obtained also vary depending on the particle diameter and shape of the raw material. For this reason, a raw material such as nitride having an approximate particle size may be prepared in accordance with the particle size and shape required for the finally obtained phosphor. In the production of the phosphor of the present embodiment, it is preferable to use a material having a particle size of 0.1 μm or more and 10 μm or less as each raw material. The raw material for the element Z is preferably a commercially available nitride, oxide, carbonate, hydroxide, basic carbonate, or simple metal. Needless to say, the purity of the Z element is preferably higher, and 2N or more, more preferably 3N or more is prepared.

An important raw material in the present embodiment, a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. needs to be determined in consideration of the firing temperature, but basically zinc (Zn), gallium (Ga) Nitrides, oxides, carbonates, hydroxides of elements selected from indium (In), thallium (Tl), germanium (Ge), tin (Sn), lead (Pb), manganese (Mn), Compounds such as basic carbonates, fluorides, chlorides, sulfides and phosphides may be used as long as the sublimation or evaporation temperature satisfies the above conditions. Of course, a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. preferably has a higher purity, and a compound having a purity of 2N or more, more preferably 3N or more is prepared.

For example, Si ₃ N ₄ (3N) and AlN (3N) are prepared as raw materials for Si element and Al element, respectively, and Eu ₂ O ₃ (4N) is prepared as Z element at a temperature of 1000 ° C to 1800 ° C. ZnO may be prepared as a compound that sublimes or evaporates. The mixing ratio of these raw materials is weighed and mixed with 2.67 mol of Si ₃ N ₄ , 1.0 mol of AlN, 0.015 mol of Eu ₂ O ₃ and 1.00 mol of ZnO, respectively. ZnO was used as a compound that sublimates or evaporates at a temperature of 1000 ° C to 1800 ° C. The sublimation of ZnO starts from around 1350 ° C, the sublimation point is 1725 ° C, and Zn is 0.10 in the β-SiAlON structure. This is due to the effect of accelerating the solid solution of Eu as an activator in the phosphor by solid solution of ppm or more and 10,000 ppm or less.

  The weighing and mixing may be performed in the air, but since the nitride of each raw material element is easily affected by moisture, it is convenient to operate in a glove box under an inert atmosphere from which moisture has been sufficiently removed. . The mixing method may be either wet or dry. However, when pure water is used as a solvent for wet mixing, the raw material is decomposed, and therefore an appropriate organic solvent must be selected. The apparatus may be a normal apparatus using a ball mill or a mortar.

Put the mixed raw material into a crucible, and at least 1400 ° C, more preferably at least 1600 ° C and not more than 1800 ° C in an atmosphere containing one or more gases selected from inert gases such as nitrogen and rare gases, and ammonia gas Bake for at least 5 minutes. When the firing temperature is 1400 ° C. or higher, it is possible to obtain a phosphor excellent in light emission characteristics through good progress of the solid-phase reaction. Further, if fired at 1800 ° C. or less, Si ₃ N can suppress the formation of Si metal by decomposition of _4, further, it is possible to prevent excessive sintering and melting can occur. In addition, since a solid-phase reaction advances rapidly, so that a calcination temperature is high, holding time can be shortened. On the other hand, even when the firing temperature is low, the desired light emission characteristics can be obtained by maintaining the temperature for a long time. However, the longer the firing time, the more the particle growth proceeds and the larger the particle shape. Therefore, the firing time may be set according to the target particle size.

The pressure in the furnace during the firing (in the present invention, the furnace pressure means a pressure component from atmospheric pressure) is preferably 0.001 MPa or more and 0.5 MPa or less, more preferably 0.1 MPa or less. . This is because by firing under a pressure of 0.5 MPa or less, it is possible to avoid excessive sintering between particles and to facilitate pulverization after firing. In addition, as the crucible, those that can be used in the above gas atmosphere such as Al ₂ O ₃ crucible, Si ₃ N ₄ crucible, AlN crucible, sialon crucible, C (carbon) crucible, BN (boron nitride) crucible are used. However, it is preferable to use a BN crucible because it can avoid contamination of impurities from the crucible.

  Further, during firing, it is preferable to perform firing in a state where the above gas atmosphere is circulated at a flow rate of, for example, 0.1 ml / min or more. This is because gas is generated from the raw material during firing, but by circulating an atmosphere containing one or more kinds of gases selected from the above-mentioned inert gases such as nitrogen and rare gases, and ammonia gas. This is because the gas generated from the raw material can be prevented from being filled in the firing furnace and affecting the reaction, and as a result, the emission characteristics of the phosphor can be prevented from deteriorating. In particular, when raw materials that decompose into oxides at high temperatures, such as carbonates, hydroxides, basic carbonates, etc., are used as raw materials, the amount of gas generated from the raw materials is large. It is preferable to exhaust the gas together with the generated gas.

In the present embodiment, it is preferable to fire the raw material as powder. In a general solid phase reaction, in consideration of the progress of the reaction due to the diffusion of atoms at the contact between the raw materials, the raw materials are often baked in the form of pellets in order to promote a uniform reaction throughout the raw materials. However, in the case of the phosphor raw material, the raw material is baked as a powder, so that the pulverization after the baking becomes easy and the shape of the primary particles becomes an ideal spherical shape. It can be made easy and is preferable. Furthermore, when carbonates, hydroxides, or basic carbonates are used as raw materials, CO ₂ gas and the like are generated by decomposition of the raw materials during firing, but the raw materials are powders, especially the particle diameter of each raw material. If the raw material is 0.1 μm or more and 10 μm or less, these gases are sufficiently removed, so that the raw material is preferably a powder from the viewpoint of not adversely affecting the light emission characteristics.

After the firing is completed, the fired product is taken out from the crucible and ground to a predetermined average particle diameter using a grinding means such as a mortar and ball mill to produce the β-SiAlON phosphor according to the present embodiment. be able to. Thereafter, the obtained phosphor is washed, classified, and surface-treated as necessary.
When other elements are used as M element, A element, B element, and Z element, and when the activation amount of Eu as an activator is changed, the blending amount at the time of charging each raw material is a predetermined composition. By adjusting to the ratio, the phosphor can be manufactured by the same manufacturing method as described above.

Hereinafter, based on an Example, this invention is demonstrated more concretely.
Example 1
In Example 1, ZnO was selected as a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C., and a β-SiAlON phosphor was produced from ZnO—AlN—Si ₃ N ₄ —Eu ₂ O ₃ . Commercially available ZnO (3N), AlN (3N), Si ₃ N ₄ (3N), Eu ₂ O ₃ (4N) are prepared as raw materials, and ZnO is 1.00 mol, AlN is 1.00 mol, Si ₃ 2.67 mol of N ₄ and 0.010 mol of Eu ₂ O ₃ were weighed and mixed in the atmosphere using a mortar. The mixed raw material is put in a BN crucible, and the inside of the firing furnace is evacuated once, then the temperature is raised to 1800 ° C at a pressure of 0.05 MPa in a nitrogen atmosphere (flow rate, 4.0 L / min) at a furnace pressure of 0.05 MPa, 1800 After holding and baking at 5.0 ° C. for 5.0 min, the mixture was cooled from 1800 ° C. to 50 ° C. in 1 hour 30 minutes. Thereafter, the fired sample was crushed using a mortar until the particle size became appropriate in the air, and the β-SiAlON phosphor according to Example 1 was obtained. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor sample. Analytical results are based on gravimetric method for Si, oxygen and nitrogen simultaneous analyzer (TC-436) manufactured by LECO for O and N, ICP for other elements, and laser diffraction scattering method for average particle size (D50). The specific surface area was measured by the BET method.

The obtained phosphor was found to be a β-SiAlON phosphor having a composition formula of Si _6-x Al _x O _x N _8-x : Z with an Al concentration of 5.63 wt%. The analysis result of Zn element is 25 ppm, which is much smaller than the amount of ZnO raw material charged at the beginning of raw material mixing. This is presumably because ZnO has a high vapor pressure (sublimation pressure), and when it was baked at 1800 ° C., it almost sublimated and went out of the mixed raw material system. The obtained phosphor powder had an average particle size (D50) of 4.305 μm and a specific surface area of 1.833 m ² / g. The average particle size (D50) was 4.305 μm, which was found to be 0.5 μm or more and 50.0 μm or less, which is preferable as the phosphor powder. When FE-SEM observation of the particles was performed, the primary particle size was about 1.0 μm. Therefore, it is considered that the emission characteristics are further improved by increasing the primary particle size by filling the conditions of the production method. Furthermore, the true density of the phosphor sample was measured and found to be 3.170 g / cc. The true density was measured using an Ultrapycnometer 1000 manufactured by QUANTACHROME. Since the density of particles is considered to change when the composition or crystal structure of the phosphor changes, it is considered that the true density of the phosphor is preferably in the range of 3.170 g / cc ± 3%.

  Next, the emission spectrum of the phosphor of Example 1 was measured. The measurement results when 460 nm and 405 nm wavelengths are irradiated as excitation light are shown in Table 2, and the emission spectrum when 460 nm wavelength light is irradiated as excitation light is shown by a thick solid line in FIG. . FIG. 1 is a graph in which the vertical axis represents the emission intensity of the phosphor as the relative intensity and the horizontal axis represents the wavelength of light. Here, the emission spectrum is a spectrum of light emitted from the phosphor when the phosphor is irradiated with light or energy having a certain wavelength.

First, the emission spectrum of the phosphor will be described with reference to FIG.
As is apparent from FIG. 1, the emission spectrum of the phosphor has a broad peak in a wide wavelength range from 470 nm to 650 nm, and the peak wavelength is 549.1 nm. (The relative intensity of the light emission intensity at this time was set to 100%.) The half-value width was determined to be 64.8 nm. The chromaticity (x, y) of the emission spectrum was determined to be x = 0.3731 and y = 0.5879. The powder had a light yellow color, and a green emission color could be confirmed visually. Since the phosphor of Example 1 has a broad peak at half width in a wide wavelength range, when used as a phosphor for white LED illumination, brightness and color rendering are compared to those using a phosphor having a sharp peak. It is possible to produce a white LED illumination that is excellent in performance. In addition, conventional white LED lighting combining blue LED and yellow phosphor has a problem that the light of green component is insufficient because it combines white with blue and yellow light. Since the phosphor emits green light, this problem can be solved by adding the phosphor.
Regarding the emission intensities of Examples and Comparative Examples described below, the maximum value of the emission spectrum when the phosphor of Example 1 is irradiated with monochromatic light having a wavelength of 460 nm as excitation light is set to 100% relative intensity.

Next, the excitation spectrum of the phosphor of Example 1 will be described with reference to FIG. FIG. 2A is a graph in which the vertical axis represents the emission intensity of the phosphor and the horizontal axis represents the wavelength of the excitation light. Here, the excitation spectrum is the excitation wavelength of the emission intensity measured by exciting the phosphor to be measured using monochromatic light of various wavelengths as excitation light, measuring the emission intensity of a certain wavelength emitted by the phosphor. Dependence is measured. In this measurement, the phosphor of Example 1 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, and the excitation dependence of the emission intensity at a wavelength of 549.1 nm emitted from the phosphor was measured.
FIG. 2A shows an excitation spectrum of the phosphor of Example 1. As is clear from FIG. 2A, it was found that the excitation spectrum of the phosphor showed high-intensity green emission with a wide range of excitation light from a wavelength of about 250 nm to about 500 nm. The peak wavelength of the excitation band is 296.1 nm, and the blue LED currently used as the excitation light for one-chip type white LED illumination, the emission wavelengths of near-ultraviolet / ultraviolet LEDs, 460 nm and 405 nm are also high. It is a phosphor that exhibits intensity and has a flat excitation band.

Next, the temperature characteristics of the phosphor of Example 1 were measured. The measurement results are shown in Table 3 and further shown in FIG.
The temperature characteristics of the phosphor of Example 1 will be described with reference to FIG. FIG. 3 is a graph in which the vertical axis represents the emission intensity of the phosphor and the horizontal axis represents the measurement temperature at which the emission intensity is measured. The measurement was performed at an arbitrary temperature in the temperature rising process from 25 ° C. to 300 ° C. After the measurement at 300 ° C. was completed, the sample was cooled and the emission intensity at 25 ° C. was measured again. The relative intensity of the emission intensity at 25 ° C. before the temperature rise was set to 100%.
Table 3 shows the measurement results of the temperature characteristics of the phosphor of Example 1. As for the temperature characteristics of the phosphor, the emission intensity gradually decreased as the temperature was increased to 89.8% at 100 ° C. and 57.5% at 300 ° C. Further, the relative light emission intensity after cooling was 100.9%, and no change was observed before and after cooling. Due to the heat generated by long-time lighting of the LED that is the excitation source of white LED lighting, the phosphor itself incorporated in the white LED lighting is considered to be about 50 to 100 ° C, but the phosphor emits light at 100 ° C. The decrease in intensity was within 15%, and the emission intensity before and after temperature rise did not change, indicating that the phosphor was excellent in temperature characteristics and thermal durability.

  Next, the powder X-ray diffraction measurement of the phosphor of Example 1 will be described with reference to FIG. FIG. 4 is a graph in which the vertical axis represents intensity (a.u.) and the horizontal axis represents diffraction angle 2θ (CoKα). In addition to the actual measurement values, FIG. 4 also shows analysis values obtained by analyzing the crystal structure using the Rietveld method based on the obtained diffraction results. The Rietveld method compares the actual diffraction intensity obtained by actual measurement with the diffraction intensity theoretically obtained from the crystal structure model constructed by predicting the crystal structure and reducing the difference between the two. As described above, various structural parameters in the latter model are refined by the least square method to derive a more accurate crystal structure. The phosphor of this embodiment was refined by the Rietveld method. For Rietveld analysis, the program “RIETAN-2000” was used. The analysis result and the actual measurement result are in very good agreement, and the value of the a-axis of the β-SiAlON phosphor of the present embodiment is 7.605 mm and the value of c-axis is 2.912 mm. It was found to have a crystal structure. It is considered that when the crystal lattice constant of the phosphor changes greatly, the atomic state around the atoms contributing to light emission changes and the light emission characteristics deteriorate. Therefore, it is preferable that the values of the a-axis and c-axis take the values shown above. In order to obtain a phosphor with better luminous efficiency, the a-axis value is 7.60 ± 0.05 mm, and the c-axis value is It is considered preferable to be within the range of 2.91 ± 0.05 mm.

  Further, the half width B is calculated for a plurality of diffraction peaks of the diffraction pattern obtained by the powder X-ray diffraction measurement of the phosphor of the present embodiment, and Scherrer's formula Dx = 0.9λ / Bcosθ (where Dx is a crystal (1 is the wavelength of the X-ray used for the measurement, B is the half-value width of the diffraction peak, and θ is the Bragg angle of the diffraction peak.) 0,0), (1,1,0), (2,2,0), (1,0,1), (2,1,0), (2,0,1), (3,0, When the crystallite size was determined from the diffraction peaks of 1) and (3,2,1), the average crystallite size was 81.1 nm, which was 50.0 nm or more.

(Example 2)
In Example 2, as shown in Table 1, the same procedure was followed as in Example 1 except that the amount of Eu ₂ O ₃ charged was 0.015 mol, the temperature was raised to 1750 ° C., and held and fired at 1750 ° C. for 3.0 h. The β-SiAlON phosphor of Example 2 was obtained. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor powder.
The obtained phosphor was found to be a β-SiAlON phosphor having a composition formula of Si _6-x Al _x O _x N _8-x : Z with an Al concentration of 5.39 wt%. The analysis result of Zn element was 23 ppm. The obtained phosphor powder had an average particle size (D50) of 4.280 μm and a specific surface area of 1.982 m ² / g. The average particle size (D50) was 4.280 μm, which was a preferable powder characteristic as a phosphor powder.

  Next, the emission spectrum of the phosphor of Example 2 was measured. The measurement results are shown by thin solid lines in Table 2 and FIG. The results in Table 2 and FIG. 1 show the measurement results of the emission spectrum when irradiated with monochromatic light having a wavelength of 460 nm as excitation light, and the phosphor has a wavelength of 470 nm to 650 nm as in Example 1. It had a broad peak in a wide wavelength range, and its peak wavelength was 547.1 nm. Further, the half width was determined to be 65.4 nm, and the chromaticity (x, y) of the emission spectrum was determined to be x = 0.3684, y = 0.5885. The powder had a light yellow color, and a green emission color could be confirmed visually. When the relative intensity of Example 1 was 100%, the relative intensity of the emission intensity of Example 2 was 83.7%.

Next, when the phosphor of Example 2 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, and the excitation dependence of the emission intensity at a wavelength of 547.1 nm emitted from the phosphor was measured, Similarly to Example 1, the excitation spectrum was found to exhibit high-intensity green light emission with a wide range of excitation light from a wavelength near 250 nm to 500 nm.
Example 2 had a composition different from that of Example 1 under firing conditions, but showed excellent light emission characteristics as in Example 1.

(Example 3)
In Example 3, Ga ₂ O ₃ is selected instead of ZnO as a compound that sublimes or evaporates at a temperature of 1000 ° C. to 1800 ° C., 1.0 mol of the Ga ₂ O ₃ is weighed and mixed, and 3.0 h at 1800 ° C. A β-SiAlON phosphor of Example 3 was obtained in the same manner as Example 1 except that it was held and fired. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor powder.
The obtained phosphor was found to be a β-SiAlON phosphor having a composition formula of Si _6-x Al _x O _x N _8-x : Z with an Al concentration of 5.83 wt%. The analytical result of Ga element was 30 ppm. The obtained phosphor powder had an average particle size (D50) of 5.484 μm and a specific surface area of 1.468 m ² / g. The average particle size (D50) was 5.484 μm, which was a preferable powder characteristic as a phosphor powder.

  Next, the emission spectrum of the phosphor of Example 3 was measured. The measurement results are shown in Table 2 and FIG. The results in Table 2 and FIG. 1 show the measurement results of the emission spectrum when irradiated with monochromatic light having a wavelength of 460 nm as excitation light, and the phosphor has a wavelength of 470 nm to 650 nm as in Example 1. It had a broad peak in a wide wavelength range, and its peak wavelength was 543.4 nm. Further, the half width was determined to be 61.6 nm, and the chromaticity (x, y) of the emission spectrum was determined to be x = 0.3449, y = 0.0.666. The powder had a light yellow color, and a green emission color could be confirmed visually. When the relative intensity of Example 1 was 100%, the relative intensity of the emission intensity of Example 3 was 77.6%.

Next, when the phosphor of Example 3 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, and the excitation dependence of the emission intensity at a wavelength of 543.4 nm emitted from the phosphor was measured, Similarly to Example 1, the excitation spectrum was found to exhibit high-intensity green light emission with a wide range of excitation light from a wavelength near 250 nm to 500 nm.
Example 3 is a result of a sample synthesized using Ga ₂ O ₃ instead of ZnO used in Example 1, and showed excellent light emission characteristics as in Example 1.

Example 4
In Example 4, instead of ZnO as a compound sublimes or evaporates at a temperature of 1800 ° C. from 1000 ° C., and select the MnO _2, the MnO ₂ is 0.5 mol weighed, except for mixing the same manner as in Example 3 Thus, the β-SiAlON phosphor of Example 4 was obtained. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor powder.
The obtained phosphor was found to be a β-SiAlON phosphor having a composition formula of Si _6-x Al _x O _x N _8-x : Z with an Al concentration of 5.43 wt%. The analysis result of Mn element was 2400 ppm. The obtained phosphor powder had an average particle size (D50) of 5.629 μm and a specific surface area of 1.436 m ² / g. The average particle size (D50) was 5.629 μm, which was a preferable powder characteristic as a phosphor powder.

  Next, the emission spectrum of the phosphor of Example 4 was measured. The measurement results are shown in Table 2 and FIG. The results in Table 2 and FIG. 1 show the measurement results of the emission spectrum when irradiated with monochromatic light having a wavelength of 460 nm as excitation light, and the phosphor has a wavelength of 470 nm to 650 nm as in Example 1. It had a broad peak in a wide wavelength range, and its peak wavelength was 539.2 nm. Further, the half value width was determined to be 61.2 nm, and the chromaticity (x, y) of the emission spectrum was determined to be x = 0.283 and y = 0.06043. The powder had a light yellow color, and a green emission color could be confirmed visually. When the relative intensity of Example 1 was 100%, the relative intensity of the emission intensity of Example 4 was 50.1%.

Next, the phosphor of Example 4 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, and the excitation dependence of the emission intensity at a wavelength of 539.2 nm emitted from the phosphor was measured. Similarly to Example 1, the excitation spectrum was found to emit green light with a wide range of excitation light from a wavelength near 250 nm to 500 nm.
Example 4 is a result of a sample synthesized by using 0.50 mol of MnO instead of 1.0 mol of ZnO used in Example 1, and showed excellent light emission characteristics as in Example 1.

(Comparative Example 1)
In Comparative Example 1, a sample was prepared without using a compound such as ZnO that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C.
As in Example 1, commercially available AlN (3N), Si ₃ N ₄ (3N), and Eu ₂ O ₃ (4N) were prepared, and each raw material was prepared with 1.00 mol of AlN and Si ₃ N ₄ as in Example 1. 10.26 mol and Eu ₂ O ₃ were weighed 0.108 mol and mixed in the atmosphere using a mortar. The mixed raw material is put in a BN crucible, and the inside of the firing furnace is evacuated once, then the temperature is raised to 1800 ° C at a pressure of 0.05 MPa in a nitrogen atmosphere (flow rate, 4.0 L / min) at a furnace pressure of 0.05 MPa, 1800 After holding and baking at 3.0 ° C. for 3.0 hours, it was cooled from 1800 ° C. to 50 ° C. in 1 hour 30 minutes. Thereafter, the fired sample was crushed using a mortar until the particle size became appropriate in the air, and the phosphor of Comparative Example 1 was obtained. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor powder.
The obtained phosphor powder had an average particle size (D50) of 2.922 μm and a specific surface area of 2.959 m ² / g.

Next, in the same manner as in Example 1, the emission spectrum of the phosphor of Comparative Example 1 was measured. The measurement results are shown in Table 2 and FIG. The results in Table 2 and FIG. 1 show the measurement results of the emission spectrum when the monochromatic light having a wavelength of 460 nm is irradiated as the excitation light, and the phosphor is broad in a wide wavelength range from 520 nm to 670 nm. The peak wavelength was 581.9 nm. Further, the half width was determined to be 91.5 nm, and the chromaticity (x, y) of the emission spectrum was determined to be x = 0.4741 and y = 0.4831. The powder had an ocher color, and a yellow emission color could be confirmed visually. When the relative intensity of Example 1 was 100%, the relative intensity of the emission intensity of Comparative Example 1 was 34.6%.
Next, when the phosphor of Comparative Example 1 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, the excitation dependence of the emission intensity at a wavelength of 581.9 nm emitted from the phosphor was measured (FIG. 2 (B )), It was found that the excitation spectrum of the phosphor showed yellow emission with excitation light having a wavelength of around 250 nm to 470 nm.

(Comparative Example 2)
In Comparative Example 2, the phosphor of Comparative Example 2 was obtained in the same manner as in Example 2 except that ZnO, which is a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C., is not used. Table 1 shows the analysis results, average particle diameter (D50), and specific surface area (BET) of the obtained phosphor powder.
The obtained phosphor powder had an average particle size (D50) of 2.641 μm and a specific surface area of 3.886 m ² / g.

Next, in the same manner as in Example 1, the emission spectrum of the phosphor of Comparative Example 2 was measured. The measurement results are shown in Table 2 and FIG. The results in Table 2 and FIG. 1 show the measurement results of the emission spectrum when irradiated with monochromatic light having a wavelength of 460 nm as the excitation light, and the phosphor has a wavelength of 520 nm to 670 nm as in Example 1. It has a broad peak in a wide wavelength range of 576.4 nm. Further, the half width was determined to be 92.7 nm, and the chromaticity (x, y) of the emission spectrum was determined to be x = 0.4619 and y = 0.4901. The powder had an ocher color, and a yellow emission color could be confirmed visually. When the relative intensity of Example 1 was 100%, the relative intensity of the emission intensity of Comparative Example 2 was 33.1%.
Next, the phosphor of Comparative Example 2 was irradiated with monochromatic light having a wavelength of 250 nm to 550 nm, and the excitation dependence of the emission intensity at a wavelength of 576.4 nm emitted from the phosphor was measured. As in Comparative Example 1, the excitation spectrum was found to show yellow emission with excitation light having a wavelength of around 250 nm to 470 nm.

(Examination on Examples 1 to 4 and Comparative Examples 1 and 2)
As apparent from Table 2, FIG. 1 and FIG. 2, the peak wavelength of the emission spectrum is 550 nm for the samples of Examples 1 to 4 to which a compound that sublimates or evaporates at a temperature of 1000 to 1800 ° C. is added. In the vicinity of Comparative Example 1 and Comparative Example 2 in which a phosphor that emits green light can be obtained, but no compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. is added, the peak wavelength of the emission spectrum A phosphor emitting yellow light was obtained at around 580 nm. As will be described later, the samples of Examples 1 to 4 are phosphors based on β-SiAlON, whereas Comparative Examples 1 and 2 are phosphors based on α-SiAlON. The characteristics are different. Since the phosphors of Examples 1 to 4 exhibit green light emission, when used for white LED illumination in which a blue LED and a yellow phosphor are combined, the light of the insufficient green component can be secured, It becomes possible to create white LED lighting with high color rendering properties.

Next, comparing the excitation spectra of Example 1 and Comparative Example 1 with reference to FIG. 2, the excitation spectrum of Example 1 is highly efficient up to around 500 nm, whereas Comparative Example 1 is a blue LED. The excitation spectrum suddenly drops from around 460 nm, which is the emission wavelength, and it can be seen that phosphors having different emission characteristics are generated in Example 1 and Comparative Example 1. Furthermore, even when the emission wavelength of the blue LED is slightly shifted, the phosphor of Example 1 has a flat excitation band, so that there is no problem that the balance of emission intensity is lost and the color tone of white changes. preferable.
In addition, the phosphors obtained in Examples 1 to 4 have excellent emission intensity and luminance, and also have a β sialon structure with excellent durability against heat and water. An excellent white LED can be produced.

<Powder X-ray diffraction pattern>
The powder X-ray diffraction patterns of the phosphors according to Examples 1 to 3 and Comparative Example 1 are shown in FIG. The diffraction pattern of the β-Si ₃ N ₄ JCPDS card (PDF # 33-1160) is also shown.
Here, a method for measuring an X-ray diffraction pattern by the powder method of FIG. 5 will be described.
The phosphor to be measured is pulverized to a predetermined average particle size (preferably 0.5 μm to 50.0 μm) using a mortar or ball mill after firing, and the material is flattened on a titanium holder. The XRD device was measured with “RINT 2000” manufactured by Rigaku Denki Co., Ltd. The measurement conditions are shown below.
Measuring instrument used: “RINT 2000” manufactured by Rigaku Corporation
X-ray tube: CoKα
Tube voltage: 40 kV
Tube current: 30 mA
Scanning method: 2θ / θ
Scanning speed: 0.3 ° / min
Sampling interval: 0.01 °
Start angle (2θ): 10 °
Stop angle (2θ): 90 °

  Further, it is considered that the deviation of the Bragg angle (2θ) is caused by the fact that the sample surface irradiated with X-rays is not flat, the X-ray measurement conditions, particularly the scanning speed. For this reason, it is considered that a slight deviation in the range in which a characteristic diffraction peak is seen is allowed. In order to suppress the deviation as much as possible, the scanning speed is set to 0.3 ° / min, Si is mixed in the phosphor sample, and the X-ray measurement is performed to correct the deviation of the Si peak, thereby adjusting the Bragg angle (2θ). Looking for. Hereinafter, the same measurement was performed for Examples 2 and 3 and Comparative Example 1 in FIG.

As is apparent from the results of the X-ray diffraction pattern by the powder method of FIG. 5, the phosphors according to Example 1 to Example 3 have the same X-ray diffraction pattern as β-Si ₃ N _4. On the other hand, the phosphor according to Comparative Example 1 has an X-ray diffraction pattern of β-SiAlON, but in addition, an X-ray diffraction pattern of α-SiAlON can be confirmed. It was found that two phases of α phase and β phase were generated. That is, the reason why the peak wavelength of the emission spectrum described above is different between Example 1 to Example 3 and Comparative Example 1 is considered to be because the generated phases are different. In the phosphor samples according to Example 1 to Example 3, the addition of a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. to the raw material promotes the formation of β phase, and is an activator Eu. Is considered to have emitted green light due to its good penetration into the β-SiAlON structure. On the other hand, in the sample of Comparative Example 1, since the compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. is not added to the raw material, the β phase is hardly generated, and the α phase is stably generated. It is considered that Eu, which is an activator, preferentially enters the α phase and thus emitted yellow light.

  In addition, conventionally, β-SiAlON phosphors were thought to be synthesized only under high temperature and high pressure, but as shown in this example, compounds such as ZnO that sublimate or evaporate at temperatures from 1000 ° C to 1800 ° C. As a result, it was possible to synthesize at a lower firing temperature and a lower pressure in the furnace as compared with the conventional production method having no such structure. The novel phosphor can be industrially sufficiently produced without requiring a large-scale manufacturing apparatus. Furthermore, the new phosphor has a raw material structure that can be easily and stably mixed in the air without using an unstable nitride raw material or metal raw material in the air, and can be easily manufactured at a low manufacturing cost. Has characteristics.

(Example 6)
<Electron beam excitation>
In Example 6, as in Example 1, a β-SiAlON phosphor was fabricated from ZnO—AlN—Si ₃ N ₄ —Eu ₂ O ₃ . As raw materials, commercially available ZnO (3N), AlN (3N), Si ₃ N ₄ (3N), Eu ₂ O ₃ (4N) were prepared.Each raw material was 1.00 mol of ZnO, 1.00 mol of AlN, 1.00 mol of Si ₃ 2.67 mol of N ₄ and 0.010 mol of Eu ₂ O ₃ were weighed and mixed in the atmosphere using a mortar. The mixed raw material is put in a BN crucible, and the inside of the firing furnace is evacuated once, then the temperature is raised to 1800 ° C at a pressure of 0.05 MPa in a nitrogen atmosphere (flow rate, 4.0 L / min) at a furnace pressure of 0.05 MPa, 1800 After holding and baking at 5.0 ° C. for 5.0 min, the mixture was cooled from 1800 ° C. to 50 ° C. in 1 hour 30 minutes. Thereafter, the fired sample was crushed using a mortar until the particle size became appropriate in the atmosphere, and the same β-SiAlON phosphor as in Example 1 was obtained.

A substrate sample in which the produced phosphor powder is dispersed in a solution, uniformly coated on a copper substrate using a coagulation sedimentation method using water glass, and the emission characteristics of the phosphor according to Example 6 are evaluated. It was. The phosphor film thickness in the produced substrate sample was calculated from the difference in thickness by measuring the thickness of the substrate coated with the phosphor and the thickness of the substrate after peeling off the phosphor film. The phosphor film thickness of each substrate sample thus measured was 33.1 μm. In addition, the amount of phosphor applied per unit area of each substrate sample produced was determined by measuring the weight of the substrate on which the phosphor was applied and the weight of the substrate after the phosphor film was peeled off. After calculating the body coating amount, it was determined by dividing the calculated phosphor coating amount by the surface area of the substrate sample. The phosphor coating amount per unit area of each substrate sample thus measured was 3.46 mg / cm ² .

Each prepared substrate sample was irradiated with an electron beam having an electron beam acceleration voltage of 25 kV and an electron beam irradiation area of 8 × 4 mm, and the excitation current value of the electron beam was set to 1 μA. The emission intensity of was measured. The measurement results are shown in FIG. In FIG. 6, the horizontal axis represents the emission wavelength (nm) and the vertical axis represents the emission intensity (relative energy intensity) of the phosphor.
It has been found that the phosphor of Example 6 exhibits extremely strong light emission when irradiated with an electron beam. Therefore, the phosphor can be sufficiently used as a phosphor for electron beam excitation.

(Example 7)
In Example 7, when the phosphor according to Example 1 is further added with a blue phosphor and a red phosphor and excited by a light emitting element (LED) that emits light at a wavelength of 405 nm, the correlated color temperature is 5000K. A phosphor mixture that emits light was produced, and the light emission characteristics and color rendering properties of a light-emitting device incorporating the phosphor mixture were evaluated. In this example, SrAlSi _6.5 O _1.25 N _9.5 : Eu was used as the blue phosphor, but BaMgAl ₁₀ O ₁₇ : Eu or a halophosphate phosphor (Sr, Ca, Ba, Mg) ₁₀ ( It is also possible to use PO ₄ ) ₆ Cl ₂ : Eu. Further, CaSiAlN ₃ : Eu was used as the red phosphor, but the red phosphor having nitrogen such as Sr ₄ AlSi ₁₁ O ₂ N ₁₇ : Eu, (Ca, Sr) Si ₅ N ₈ : Eu, or SrS: It is also possible to use a sulfide-based red phosphor such as Eu or CaS: Eu.

(1) Preparation of phosphor sample A green phosphor was produced in the same manner as in Example 1 by the method described in Example 1.
Blue phosphor SrAlSi _6.5 O _1.25 N _9.5 : Eu was manufactured by the following method.
As in Example 1, commercially available SrCO ₃ (3N), Al ₂ O ₃ (3N), AlN (3N), and Si ₃ N ₄ (3N) are prepared as raw materials, and Eu ₂ O is used as the Z element. Prepare ₃ (3N). These raw materials, the molar ratio of each element is Sr: Al: Si: O: Eu = 0.970: 1: 6.5: 1.25: such that 0.030, respectively the mixing ratio of each raw material, a SrCO ₃ 0.970 mol, Al ₂ O ₃ 0.25 / 3 mol, AlN (1.0-0.25 / 3 × 2) mol, Si ₃ N ₄ 6.5 / 3 mol, Eu ₂ O ₃ 0.030 / 2 mol were weighed and mixed. The mixed raw material is put in a BN crucible, and the inside of the firing furnace is evacuated once, then the temperature is raised to 1800 ° C at a pressure of 0.05 MPa in a nitrogen atmosphere (flow rate, 4.0 L / min) at a furnace pressure of 0.05 MPa, 1800 After holding and baking at 3.0 ° C. for 3.0 hours, it was cooled from 1800 ° C. to 50 ° C. in 1 hour 30 minutes. Thereafter, the fired sample was crushed using a mortar until the particle size became appropriate in the air to obtain a sample.

On the other hand, a red phosphor CaSiAlN ₃ : Eu was manufactured by the following method.
Commercially available Ca ₃ N ₂ (2N), AlN (3N), Si ₃ N ₄ (3N), Eu ₂ O ₃ (3N) are prepared, and the molar ratio of each element is Ca: Al: Si: Eu = 0.970: Each raw material was weighed so as to be 1.00: 1.00: 0.030, and mixed in a nitrogen atmosphere using a mortar. The mixed raw material is heated to 1500 ° C in a nitrogen atmosphere at a heating rate of 15 ° C / min, held and fired at 1500 ° C for 12 hours, and then cooled from 1500 ° C to 200 ° C in 1 hour. A phosphor having the composition formula CaSiAlN ₃ : Eu was obtained. The obtained sample was pulverized and classified to prepare a red phosphor sample.

(2) Preparation of phosphor mixture For each of the three types of phosphor samples, blue, green, and red phosphors, emission spectra were measured when excited with excitation light having a wavelength of 405 nm. From the emission spectra, The relative mixing ratio at which the correlated color temperature of both phosphor mixtures was 5000 K was determined by simulation. The result of the simulation was (blue phosphor): (green phosphor: Example 1): (red phosphor) = 55.4: 34.6: 10.0. Based on the results, each phosphor was weighed and mixed to obtain a phosphor mixture.
However, a preferable mixing ratio may deviate from the simulation result depending on the emission wavelength of the light emitting portion (excitation wavelength of the phosphor mixture) and the emission efficiency of the phosphor with respect to the excitation light. In such a case, an actual emission spectrum shape may be adjusted by appropriately adjusting the blending ratio of the phosphors.

(3) Evaluation with Light Emitting Element The light emitting characteristics and color rendering properties of the light emitting device when excited using a light emitting element (LED) that emits light at a wavelength of 405 nm were evaluated. First, an ultraviolet LED element (emission wavelength: 405 nm), which is a nitride semiconductor, was prepared as a light emitting part. Further, a phosphor mixture prepared by mixing the β-SIALON phosphor according to Example 1 and various phosphors, an epoxy resin, and a dispersant were mixed to prepare a phosphor mixture. The resin preferably has a higher visible light transmittance and higher refractive index. If the above conditions are satisfied, the resin is not limited to an epoxy resin but may be a silicon resin. The dispersant may be used by mixing a small amount of SiO ₂ fine particles. The mixture was sufficiently stirred and applied onto the LED element by a known method to produce a white LED illumination (light emitting device). Since the light emission color and light emission efficiency vary depending on the phosphor and resin ratio of the mixture and the coating thickness, the conditions may be adjusted in accordance with the target color temperature.

Table 4 and FIG. 7 show the results of the emission spectrum when 20 mA was applied to the produced white LED illumination. FIG. 7 is a graph with the relative emission intensity on the vertical axis and the emission wavelength (nm) on the horizontal axis. The emission spectrum of the white LED illumination according to Example 7 is indicated by a solid line.
The phosphor was excited and emitted by blue light emitted from the light emitting portion, and white LED illumination was obtained that emits white light having an emission spectrum having a continuous broad peak in the wavelength range of 400 nm to 700 nm. When the color temperature, chromaticity, and color rendering properties of the light emission were measured, the color temperature was 5003K, the chromaticity was x = 0.3456, y = 0.3584, the average color rendering index (Ra) was 88, and the special color rendering index R9 was 74 and R15 were 96.

It is a graph which shows each emission spectrum of the fluorescent substance of Example 1 to Example 4, and the fluorescent substance of Comparative Examples 1 and 2. 2 is a graph showing an excitation spectrum of Example 1. 6 is a graph showing an excitation spectrum of Comparative Example 1. 3 is a graph showing temperature characteristics of the phosphor of Example 1. It is a graph which shows the actual value and analysis value in powder X-ray diffraction measurement about the fluorescent substance of Example 1. It is a graph which shows the powder X-ray-diffraction pattern about the fluorescent substance of Example 1- Example 3 and the comparative example 1. FIG. 10 is a graph showing electron beam excitation characteristics in the phosphor film of Example 6. 10 is a graph showing an emission spectrum in white LED illumination (light emitting device) of Example 7. It is sectional drawing which shows a bullet-type LED light-emitting device typically. It is sectional drawing which shows a reflection type LED light-emitting device typically.

Explanation of symbols

1. Phosphor mixture 2, LED light emitting material 3, lead frame 4, resin 8, reflective surface

Claims (20)

A production phase represented by a composition formula Si _6-x Al _x O _x N _8-x : Z (wherein the Z element is an element acting as an activator in the phosphor), and 1000 ° C. to 1800 A metal element constituting a compound that sublimes or evaporates at a temperature of ° C.,
A phosphor containing 0.10 ppm or more and 10000 ppm or less of a metal element constituting a compound that sublimes or evaporates at a temperature of 1000 ° C. to 1800 ° C. The phosphor according to claim 1,
The metal element constituting the compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C. is zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin (Sn) A phosphor characterized by being one or more elements selected from lead (Pb) and manganese (Mn). The phosphor according to claim 1 or 2,
A phosphor characterized by 0.3 ≦ x ≦ 0.9. The phosphor according to any one of claims 1 to 3,
A phosphor characterized in that the Z element is at least one element selected from Eu, Ce, Pr, Tb, Yb, and Mn. The phosphor according to any one of claims 1 to 4,
The phosphor characterized in that the crystal system of the generation phase of the phosphor is hexagonal. The phosphor according to any one of claims 1 to 5,
A phosphor having a crystallite size (Dx) of a generation phase of the phosphor of 50 nm or more. The phosphor according to any one of claims 1 to 6,
A phosphor characterized in that the phosphor is in a powder form. The phosphor according to claim 7,
An average particle diameter (D50) of the phosphor particles is 0.5 μm or more and 50.0 μm or less. A method for producing the phosphor according to any one of claims 1 to 8,
Mixing the raw materials of the phosphor to obtain a mixture;
Installing the mixture in a firing furnace and heating to form a fired product;
Crushing the fired product to obtain a phosphor,
As a compound that sublimates or evaporates at a temperature of 1000 ° C. to 1800 ° C., zinc (Zn), gallium (Ga), indium (In), thallium (Tl), germanium (Ge), tin (Sn), lead (Pb) A method for producing a phosphor, comprising adding one or more compounds selected from oxides of manganese (Mn) to the mixture. It is a manufacturing method of the fluorescent substance according to claim 9,
The mixture is placed in a BN crucible in powder form and placed in a firing furnace,
The atmosphere gas in the firing furnace is a gas containing at least one selected from nitrogen gas, rare gas, and ammonia gas, and the selected gas is circulated in the firing furnace at a rate of 0.1 ml / min or more. However, a method for producing a phosphor, comprising heating at a temperature of 1400 ° C. or higher and 1800 ° C. or lower. It is a manufacturing method of the fluorescent substance according to claim 9 or 10,
An internal pressure in the firing furnace is set to 0.001 MPa or more and 0.5 MPa or less.   A phosphor comprising the phosphor according to claim 1, a light emitting unit that emits light of a first wavelength, and a part or all of the light of the first wavelength as excitation light, wherein the fluorescence A light emitting device that emits light having a wavelength different from the first wavelength from a body. The light-emitting device according to claim 12,
The light emitting device is characterized in that the first wavelength is a wavelength of 350 nm to 500 nm. The light-emitting device according to claim 12 or 13,
A light emitting device having an average color rendering index Ra of 80 or more. The light-emitting device according to any one of claims 12 to 14,
A light emitting device having a special color rendering index R15 of 80 or more. The light-emitting device according to any one of claims 12 to 15,
A light emitting device having a special color rendering index R9 of 60 or more. The light-emitting device according to any one of claims 12 to 16,
A light emitting device having a correlated color temperature in the range of 7000 K to 2500 K. The light-emitting device according to any one of claims 12 to 17,
A light-emitting device, wherein the light-emitting portion emitting the first wavelength is an LED.   A phosphor film for electron beam excitation produced using the phosphor according to claim 1. An electron beam excitation color display device produced using the phosphor according to claim 1.

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