JP2009263201A - Crystalline silicon nitride, its production method, phosphor using the silicon nitride, phosphor-containing composition, light-emitting device, illuminating device, image display, sintered compact and pigment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: silicon nitride having high whiteness and reflectance; a method for producing the same; a phosphor having clear object color and high luminous brightness in comparison with a conventional one; a phosphor-containing composition; a light emitting device using the phosphor; an illuminating device; an image display; a ceramic having high whiteness; and a pigment. <P>SOLUTION: As a raw material of the phosphor, crystalline silicon nitride, having a crystal phase and exhibiting reflectance of ≥85% when it is irradiated with a light having a wavelength of 525 nm, is used. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to crystalline silicon nitride having high whiteness and a method for producing the same, and a phosphor using the crystalline silicon nitride as a raw material, the phosphor-containing composition, a light emitting device, an illumination device, and an image display device using the phosphor And a sintered body and a pigment using the silicon nitride. More specifically, the present invention relates to crystalline silicon nitride having a high reflectivity, a method for producing the same, and various uses using the silicon nitride. Specifically, the phosphor has a clear object color and higher emission luminance than before, and the phosphor contains The present invention relates to a composition, a light emitting device using the phosphor, an illumination device and an image display device, and ceramics and pigments having high whiteness.

  Silicon nitride is an inorganic material used for various applications. Major applications include (1) raw materials for nitride inorganic materials represented by phosphors, (2) ceramics, and (3) pigments.

(1) In the phosphor field, in recent years, nitrides and oxynitride phosphors containing Si have attracted attention as phosphors for image display devices and illumination devices that use blue LEDs or near-ultraviolet LEDs as excitation light sources. Yes. For example, a phosphor having a host crystal structure represented by (Ca, Sr) AlSiN ₃ (hereinafter, referred to as “CASN phosphor” as appropriate. See Patent Documents 1 and 2), (Ca, Sr, Ba) Si. Phosphors having a host crystal structure typified by ₂ O ₂ N ₂ (hereinafter appropriately referred to as “SION phosphors”, see Patent Document 3), (Ca, Sr, Ba) ₀ to _0.2 (Si , Al) ₁₂ (O, N) ₁₆ having a host crystal structure (hereinafter referred to as “sialon phosphor” as appropriate. See Patent Documents 4 and 5), (Sr, Ba) _2. Various phosphors such as a phosphor having a host crystal structure typified by Si ₅ N ₈ (hereinafter referred to as “258 phosphor” as appropriate; see Patent Document 6) have been developed. As these silicon source and nitrogen source, silicon nitride is an important raw material.

  (2) In the field of ceramics, a silicon nitride sintered body is a representative engineering ceramic as a material exhibiting high strength and excellent thermal shock resistance. However, the color of the silicon nitride sintered body known so far is black or gray (see Non-Patent Documents 1 and 2). For applications that require transparency or translucency, alumina, which is the same engineering ceramic, is used. It was used exclusively.

  (3) In addition to this, it is also known to use a commercially available product or silicon nitride obtained by a known manufacturing method for a heat shielding material (Patent Documents 7 and 8) and a cosmetic (Patent Document 9) using a pigment. ing.

JP 2006-8721 A JP 2006-8948 A JP-T-2005-530917 Japanese Patent No. 3826131 JP 2005-255895 A Special table 2003-515665 gazette JP 2000-212475 A JP-A-2005-97462 JP 2000-229809 A Kyocera Corporation website Fine ceramic material characteristics table, [online], [searched July 18, 2008], Internet <URL: http://www.kyocera.co.jp/prdct/fc/product/pdf/material. pdf> Japan Fine Ceramics Co., Ltd. Homepage Product introduction [online], [Search July 18, 2008], Internet <URL: http://www.japan-fc.co.jp/products/pro_9.html>

In recent years, there has been an increasing demand for image display devices and illumination devices with higher luminance and higher luminous efficiency, and the appearance of phosphors with higher luminance than before is desired.
In addition, as described above, silicon nitride is a useful material used in various applications, but all of the silicon nitrides disclosed so far have low reflectivity, and all of these applications have limited applications. It was.

  The present invention was devised in view of the above problems, and provides a phosphor having higher brightness than the conventional one, and a phosphor-containing composition, a light-emitting device, a lighting device, and an image display device using the phosphor. Another object of the present invention is to provide crystalline silicon nitride having a higher reflectivity than before, a method for producing the same, and a sintered body and a pigment using the crystalline silicon nitride.

  Conventionally, the relationship between the raw material properties and the phosphor physical properties has not been particularly focused on until now, but the present inventors have focused on silicon nitride, which is a phosphor raw material, in order to solve the above-mentioned problems. As a result, by performing a specific treatment, it is possible to obtain crystalline silicon nitride with extremely high reflectance, and when a phosphor is manufactured using this, the object color of the phosphor and The inventors have found that the luminance is improved and have completed the present invention.

  That is, the gist of the present invention resides in crystalline silicon nitride which has a crystalline phase and has a reflectance of 85% or more when irradiated with light having a wavelength of 525 nm (claim 1).

At this time, the crystalline silicon nitride of the present invention preferably has an impurity carbon content of 0.06 wt% or less (claim 2).
In the crystalline silicon nitride of the present invention, the crystal phase is preferably β-type (Claim 3).

Another gist of the present invention is a method for producing crystalline silicon nitride, characterized by heat-treating silicon nitride at a temperature of 1500 ° C. or higher in a nitrogen gas-containing atmosphere having an N ₂ partial pressure of 0.4 MPa or higher. (Claim 4).
At this time, it is preferable to heat-treat silicon nitride in advance at a temperature of 800 to 1300 ° C. in an oxygen gas-containing atmosphere having an O ₂ partial pressure of 0.01 MPa or more.
It is also preferable to perform the heat treatment in the presence of SiO ₂ (claim 6).

Still another subject matter of the present invention lies in a phosphor characterized in that the crystalline silicon nitride of the present invention is used as a raw material (claim 7).
At this time, the phosphor of the present invention is preferably a phosphor selected from the group consisting of nitridosilicate, nitridoaluminosilicate, oxonitridosilicate, oxonitridoaluminosilicate, and carbonitridoaluminosilicate (claim) Item 8).

The fluorescence of the present invention is preferably a phosphor represented by the following formula [I] or [II] (claim 9).
^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
(In Formula [I], M ¹ represents at least one type of activating element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb; ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn, L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the periodic table, and at least L Represents a part of Si element, and x, y, z, u, v, and w each represent a numerical value in the following range.
0.00001 ≦ x ≦ 3
0 ≦ y ≦ 2.99999
2.6 ≦ x + y + z ≦ 3
0 <u ≦ 11
6 <v ≦ 25
0 <w ≦ 17)
M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
(In formula [II], M ³ represents an activating element, and e represents a positive number satisfying 0 <e ≦ 0.2.)

Still another gist of the present invention is that when the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value is 97 or more, the a ^* value is -21 or less, and the b ^* value is 35 or more. It exists in the fluorescent substance characterized by satisfy | filling either and represented by said Formula [I] (Claim 10).

  Still another subject matter of the present invention lies in a phosphor having an external quantum efficiency of 0.35 or more and represented by the formula [I] (claim 11).

Still another gist of the present invention is that when the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value is 103 or more, the a ^* value is −23 or less, and the b ^* value is 63 or more. It exists in the fluorescent substance characterized by satisfy | filling either and represented by said Formula [II] (Claim 12).
Further, this phosphor has an emission peak wavelength of 550 nm to 570 nm, an L ^* value of 100 or more and a b ^* value of 77 or more, and is preferably represented by the following formula [II ′] (claims) 13).
M ³ _e (Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II ′]
(In Formula [II ′], M ³ represents an activator element, and e represents a positive number satisfying 0 <e ≦ 0.2.)

  Still another subject matter of the present invention lies in a phosphor having an external quantum efficiency of 0.57 or more and represented by the formula [II] (claim 14).

Still another subject matter of the present invention lies in a phosphor represented by the following formula [I ′] (claim 15).
M ¹ _χ (Ba, Ln) _a (L, Al) _b O _c N _d [I ′]
(In Formula [I ′], M ¹ represents at least one type of activating element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb. Ln represents La, Ce, Pr, Nd, Y and Gd, L is a metal element selected from the metal elements belonging to Group 4 or Group 14 of the periodic table, and at least a part of L is Si element Χ, a, b, c, and d represent numerical values in the following ranges, respectively.
0.00001 ≦ χ ≦ 0.4
2.6 ≦ a ≦ 2.99999
5 ≦ b ≦ 7
11 <c <13
0 <d <2.4)

  The phosphor of the present invention represented by the formula [I ′] is preferably a solid solution of the phosphor represented by the formula [I] and the langasite (claim 16).

  Still another subject matter of the present invention lies in a phosphor-containing composition comprising the phosphor described above and a liquid medium (claim 17).

Still another subject matter of the present invention includes a first light emitter and a second light emitter that emits visible light by irradiation of light from the first light emitter, and the second light emitter is the above-mentioned. The present invention resides in a light emitting device containing at least one of the phosphors as the first phosphor (claim 18).
In this light-emitting device, it is preferable that the second light emitter contains one or more kinds of phosphors having different emission peak wavelengths from the first phosphor as the second phosphor.

  Still another subject matter of the present invention lies in an illuminating device comprising the light emitting device of the present invention (claim 20).

  Still another subject matter of the present invention lies in an image display device comprising the light emitting device of the present invention (claim 21).

  Still another subject matter of the present invention lies in a sintered body obtained by sintering the crystalline silicon nitride of the present invention (claim 22).

  Still another subject matter of the present invention lies in a pigment comprising the crystalline silicon nitride of the present invention (claim 23).

  According to the present invention, silicon nitride that is more preferable as a raw material for various uses such as sintered bodies and pigments having high whiteness can be obtained, and used for a light emitting device, an image display device, and a lighting device that have higher brightness than conventional ones. More preferred phosphors are provided.

  Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and various modifications can be made without departing from the scope of the present invention.

[1. Silicon nitride]
[1-1. crystalline]
The crystalline silicon nitride of the present invention (hereinafter appropriately referred to as “silicon nitride of the present invention”) is silicon nitride having a crystalline phase.
As the crystal phase of silicon nitride, a low temperature stable α type and a high temperature stable β type are known. These are each subjected to X-ray diffraction to register patterns registered in PDF (Powder Diffraction File) (for example, α-silicon nitride: 83-0700, 76-1407, 71-0570, etc., β-silicon nitride: 29 -1132, 73-1208, 82-0702, etc.).

  The crystalline phase of the silicon nitride of the present invention may be any of α-type only, β-type only, or a mixture of α-type and β-type, but at least β-type is preferably present, More preferably, it is only a mold.

  The silicon nitride of the present invention may contain a part of the amorphous phase in addition to the above crystalline phase, but it is preferable that the amorphous phase is small, usually 50% or less, preferably 30% or less, more preferably 20% or less. More preferably, it is 10% or less, particularly preferably 5% or less, and most preferably no amorphous phase.

[1-2. Reflectance]
The silicon nitride of the present invention has a reflectance of 85% or more when irradiated with light having a wavelength of 525 nm, preferably 88% or more, more preferably 90% or more, and still more preferably 93% or more. The higher the reflectivity, the better. The upper limit is 100%.

The reflectance measurement method may be performed in accordance with a normal reflection spectrum measurement method. Specifically, the reflectance can be measured by the following method.
That is, the silicon nitride powder to be measured is packed in a cell with a sufficiently smooth surface so that the measurement accuracy is maintained, and is attached to a condenser such as an integrating sphere. The condensing device such as an integrating sphere is irradiated with light such as an Xe lamp, and the spectrum of reflected light obtained is measured using a spectroscopic measurement device such as MCPD2000, MCPD7000 manufactured by Otsuka Electronics Co., Ltd. The reflectance value at each wavelength obtained here is a substance whose reflectance with respect to the light of the light source is known (for example, “manufactured by Labsphere having a reflectance R of 99% with respect to excitation light having a wavelength of 525 nm” The reflectance can be obtained by performing correction based on the reflectance of “Spectralon” or the like.

[1-3. Carbon content]
The silicon nitride of the present invention usually has an impurity carbon content of 0.1% by weight or less, but preferably has an impurity carbon content of 0.06% by weight or less. The amount of impurity carbon is more preferably 0.05% by weight or less, further preferably 0.04% by weight or less, and particularly preferably 0.03% by weight or less. The smaller the amount of impurity carbon, the more preferable, but it is usually 0.000001% by weight or more.
The measurement of the carbon amount can be performed by a normal elemental analysis method.

[1-4. Method for producing silicon nitride]
The method for producing silicon nitride of the present invention is not limited, but among them, a method of producing a raw material silicon nitride through a step of heat treatment under predetermined conditions (hereinafter referred to as “the method of producing silicon nitride of the present invention” as appropriate) ) Is preferred. Hereinafter, the method for producing silicon nitride of the present invention will be described in detail.

(Raw material silicon nitride)
There is no particular limitation on the raw material silicon nitride used as a raw material for obtaining the silicon nitride of the present invention, and any silicon nitride obtained by a known method can be used. As specific examples, it can be obtained by any one of the following (a) a method of directly nitriding metal silicon, (b) a method using silicon halide as a raw material, and (c) a method of reducing and nitriding silicon dioxide. The silicon nitride produced can be used.

(A) Direct nitriding method 3Si + 2N ₂ → Si ₃ N ₄
3Si + 4NH ₃ → Si ₃ N ₄ + 6H ₂
The metal silicon fine powder is placed in the presence of N ₂ or NH ₃ under a temperature rising condition controlled from around 1100 ° C., and nitriding is completed at 1200 to 1450 ° C., followed by pulverization and purification treatment as necessary. .

(B) Silicon Halide Method The silicon halide method includes the following (1) imide decomposition method and (2) gas phase method.
(1) Imide decomposition method (liquid phase method)
SiCl ₄ + 6NH ₃ → Si (NH) ₂ + 4NH ₄ Cl
Si (NH) ₂ → Si ₃ N ₄ + 2NH ₃
Silicon tetrachloride is reacted with ammonia in an organic solvent at room temperature or lower to obtain silicon diimide, which is then thermally decomposed at a temperature of about 1100 ° C. to obtain amorphous silicon nitride. Next, it is crystallized to obtain α-type silicon nitride.

(2) Gas phase method 3SiCl ₄ + 4NH ₃ → Si ₃ N ₄ + 12HCl
3SiH ₄ + 4NH ₃ → Si ₃ N ₄ + 12H ₂
Silicon tetrachloride or SiH ₄ and ammonia are reacted at a gas phase of 1100 to 1200 ° C. to obtain amorphous silicon nitride. Next, this is heat-treated at 1450 to 1500 ° C. to obtain α-type silicon nitride.

(C) Reduction nitriding method 3SiO ₂ + 6C + 2N ₂ → Si ₃ N ₄ + 6CO
The raw material silicon dioxide and carbon fine powder are reduced and nitrided at 1500 ° C. under N ₂ gas flow, and then subjected to heat treatment at 700 ° C. in an oxidizing atmosphere to remove residual carbon.

  The raw material silicon nitride having a crystal phase obtained by the above method has a reflectance of 83% or less when irradiated with light having a wavelength of 525 nm, and more generally 80% or less. is there. Further, the carbon content is usually 0.06% by weight or more, and more generally 0.09% by weight or more.

(Heat treatment)
In the method for producing silicon nitride of the present invention, the raw material silicon nitride is subjected to a heat treatment at a temperature of 1500 ° C. or higher in a nitrogen gas-containing atmosphere having an N ₂ partial pressure of 0.4 MPa or higher. Get.

  Specifically, the raw material silicon nitride is filled in a heat-resistant container such as a crucible or a tray made of a material having low reactivity, and then fired. Examples of the material of the heat-resistant container used during such heat treatment include ceramics such as alumina, boron nitride, silicon nitride, silicon carbide, magnesium, mullite, metals such as platinum, molybdenum, tungsten, tantalum, niobium, iridium, rhodium, Or the alloy which has them as a main component, carbon (graphite), etc. are mentioned. Of these, heat resistant containers made of boron nitride, alumina, silicon nitride, silicon carbide, platinum, molybdenum, tungsten, and tantalum are preferable.

In the temperature raising process during the heat treatment, it is preferable that a part of the temperature is reduced under reduced pressure. Specifically, it is preferably room temperature or higher, preferably 1500 ° C. or lower, more preferably 1200 ° C. or lower, still more preferably. At any point in the temperature range of 1000 ° C. or lower, a nitrogen-containing gas is introduced into the system after being in a reduced pressure state (specifically, a range of usually 10 ⁻² Pa or more and less than 0.1 MPa).

  At this time, if necessary, it may be maintained at the target temperature, usually for 1 minute or more, preferably 5 minutes or more, more preferably 10 minutes or more. The holding time is usually 5 hours or less, preferably 3 hours or less, more preferably 1 hour or less.

  As the nitrogen-containing gas, there is no particular problem as long as the partial pressure of the nitrogen gas is 0.4 MPa or more and the gas is inert to the heater of the temperature raising device and silicon nitride. As a specific example, a mixed gas of argon, CO, hydrogen, ammonia or the like and nitrogen gas can be used. Among these, nitrogen gas or argon or a mixed gas of hydrogen gas and nitrogen gas is preferable, nitrogen gas or a mixed gas of nitrogen gas and argon gas is more preferable, and nitrogen gas is particularly preferable. Further, the partial pressure of nitrogen gas is preferably higher, more preferably 99.999% by volume of nitrogen gas.

  After introducing the nitrogen-containing gas into the system, the temperature is further raised to a temperature of usually 1500 ° C. or higher, preferably 1800 ° C. or higher, more preferably 1900 ° C. or higher, and heat treatment of silicon nitride is performed. The upper limit of the heat treatment temperature is not particularly limited as long as it is lower than the decomposition temperature of silicon nitride, although it depends on the pressure in the firing system. For example, when the pressure in the firing system is 2 MPa or less, the temperature is usually 2500 ° C. or less, preferably 2200 ° C. or less, more preferably 2100 ° C. or less.

  The heat treatment time is usually 0.5 hours or more, preferably 1 hour or more, more preferably 2 hours or more, although it depends on the heat treatment temperature. The firing time is preferably longer, but is usually 100 hours or shorter, preferably 50 hours or shorter, more preferably 24 hours or shorter, and further preferably 12 hours or shorter.

  The heat treatment of the silicon nitride may be performed on the raw material silicon nitride previously produced and isolated by the above-described method, or may be performed subsequent to the nitriding treatment in the raw material silicon nitride manufacturing process. In the latter case, the silicon nitride of the present invention can be obtained in one step from a silicon nitride raw material such as metal silicon, silicon halide and silicon dioxide.

In addition, before performing the above-described heat treatment, if necessary, an O ₂ partial pressure is usually 0.01 MPa or more, and usually in an oxygen gas-containing atmosphere where the pressure is usually 0.1 MPa or less, usually 800 ° C. or more, preferably It is preferable to perform a step (preliminary heat treatment) of heat-treating silicon nitride at a temperature of 900 ° C. or higher, more preferably 1000 ° C. or higher, more preferably 1100 ° C. or higher, and usually 1300 ° C. or lower, preferably 1200 ° C. or lower. Thereby, the particle size of the obtained β-silicon nitride can be increased.

On the other hand, when heat-treating the raw material silicon nitride in the heat treatment described above, it is preferable to perform the heat treatment in the presence of SiO ₂ . Thereby, the particle size of the obtained β-silicon nitride can be increased.
At this time, the amount of SiO ₂ coexisting is not limited, but the amount of SiO ₂ with respect to 100 parts by weight of raw material silicon nitride is usually 0.1 parts by weight or more, preferably 0.5 parts by weight or more, more preferably 1 part by weight. It is usually 15 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight or less.
As described above, when a small amount of oxygen atoms coexists when heat-treating silicon nitride, the particle diameter of the obtained β-silicon nitride tends to increase. Therefore, in order to increase the particle diameter of the phosphor particles, it is preferable to use silicon nitride that has been subjected to the above treatment.

After the heat treatment is completed, heat is released to room temperature, and processing such as pulverization and sieving is performed as necessary.
As the pulverization method, for example, a known pulverization method such as a dry pulverizer such as a hammer mill, a roll mill, a ball mill, or a jet mill, or pulverization using a mortar and pestle can be arbitrarily used.
Moreover, in sieving, it is possible to use various commercially available sieves, but when using the obtained silicon nitride as a phosphor raw material, it is better to use a nylon mesh than a metal mesh, This is preferable from the viewpoint of preventing impurity contamination.

In the silicon nitride of the present invention, the particle size of the powder is not particularly limited and may be appropriately selected depending on the intended use. For example, when the silicon nitride of the present invention is used as a raw material for a phosphor, the weight median diameter (D ₅₀ ) is usually 0.01 μm or more, preferably 0.1 μm or more, more preferably 1 μm or more, Moreover, it is the range of 100 micrometers or less normally, Preferably it is 30 micrometers or less, More preferably, it is 20 micrometers or less.

  The weight median diameter of silicon nitride can be arbitrarily measured according to a known method, but can be measured using a device such as a laser diffraction / scattering particle size distribution measuring device.

[1-5. Use of silicon nitride]
The silicon nitride of the present invention can be used as a raw material for various phosphor raw materials; ceramic raw materials such as enamels, abrasives, insulators, dielectrics, heat-resistant materials; pigments; various inorganic materials such as cosmetics. In particular, since it has a higher reflectance than that of the conventional white color, it can be expected to be used for optical materials in addition to conventional fields that require thermal shock resistance.

[2. Phosphor]
The phosphor of the present invention is obtained using the silicon nitride of the present invention as the phosphor material. In addition, the phosphor of the present invention usually has higher saturation and quantum efficiency in the object color, and more preferably has a higher luminance than known phosphors having the same composition. As described above, the inventors found for the first time that the characteristics such as saturation and quantum efficiency in the object color of the phosphor are related to the reflectance of the phosphor material (particularly, the above-mentioned silicon nitride). Is.

Hereinafter, in the description about the phosphor, the relationship between the color name and the chromaticity coordinate is all based on the JIS standard (JIS Z8110 and Z8701).
Further, in the composition formula of the phosphors in this specification, each composition formula is delimited by a punctuation mark (,). In addition, when a plurality of elements are listed separated by commas (,), one or two or more of the listed elements may be included in any combination and composition. For example, the composition formula “(Ca, Sr, Ba) Al ₂ O ₄ : Eu” has “CaAl ₂ O ₄ : Eu”, “SrAl ₂ O ₄ : Eu”, and “BaAl ₂ O ₄ : Eu”. If: the _{"Ca 1-x Sr x Al 2} O 4 Eu ": a _{"Sr 1-x Ba x Al 2} O 4 Eu ": the _{"Ca 1-x Ba x Al 2} O 4 Eu " _{"Ca 1-x-y Sr x} Ba y Al 2 O 4: Eu " and all assumed to generically indicated (in the above formula, 0 <x <1,0 <y <1,0 <X + y <1).

[2-1. Types of phosphors]
First, the phosphor of the present invention is not particularly limited as long as the silicon nitride of the present invention is used as a raw material. Examples thereof include nitride phosphors and oxynitride phosphors containing silicon atoms.

Examples of the nitride phosphor and oxynitride phosphor containing the silicon atom include:
CaSiN ₂ : Eu, ZnSiN ₂ : Mn, (Ca, Sr, Ba, Zn) ₂ Si ₅ N ₈ : Eu, (Ca, Sr, Ba, Zn) Si ₇ N ₁₀ : Eu, (Ca, Sr, Ba) Si (N, O) ₂ : alkaline earth metal silicon nitride phosphor such as Eu, and _{3 such} as La ₃ Si ₆ (N, O) ₁₁ : Ce, LaSi ₃ (N, O) ₅ : Ce Nitridosilicates represented by valent rare earth element-containing silicon nitride phosphors,
(Ca, Sr) AlSi (N, O) ₃ : Eu, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Ca, Sr) AlSi ₄ (N, O) ₇ : Eu, (Ca , Sr, Ba) AlSi ₄ (N, O) ₇ : Nitolide aluminosilicates represented by Si and Al-containing nitride phosphors such as Ce,
(Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu, Ba ₃ Si ₆ O ₁₂ N ₂ : Eu, (Ca, Sr, Ba) ₃ (Si, Ge) ₆ O ₁₂ N ₂ : (Eu, Ce , Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₆ O ₉ N ₄ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₆ O ₃ N ₈ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₇ O ₁₂ N _8/3 : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₂ N _14/3 : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₂ N ₆ : (Eu, Ce, Mn), (Ca, Sr, Ba) _{3 (Si, Ge) 28/3 O} 12 N 22/3: (Eu, Ce, Mn), (Ca, Sr, Ba) 3 ( _{i, Ge) 29/3 O 12 N} 26/3: (Eu, Ce, Mn), (Ca, Sr, Ba) 3 (Si, Ge) 6.5 O 13 N 2: (Eu, Ce, Mn) , (Ca, Sr, Ba) ₃ (Si, Ge) ₇ O ₁₄ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₆ N ₂ : (Eu, (Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₉ O ₁₈ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₁₀ O ₂₀ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₁₁ O ₂₂ N ₂ : (Eu, Ce, Mn), etc., and alkaline earth metal silicate nitride phosphors _{, La 3 Si 8 O 4 N} 11: Ce, La 3 Si 6 O 12 N 2: 3 -valent rare earth source, such as Ce Oxonitridosilicate typified by containing silicon oxynitride-based fluorescent material,
Si and Al-containing oxynitride phosphors such as Ca-α-SiAlON: Eu, Y-α-SiAlON: Ce, β-SiAlON: Eu, SrSi ₉ Al ₁₉ ON ₃₁ : Eu, SrSiAl ₂ O ₃ N ₂ : Eu Oxonitridoaluminosilicates represented by
And carbonitride aluminosilicates typified by phosphors having CaSi ₅ N ₆ C as a base crystal.
In manufacturing the phosphor, it may be appropriately manufactured according to a known method except that the silicon nitride of the present invention is used as a raw material.

  Among the above phosphors, a phosphor represented by any of the following formulas [I] to [IV] is preferable, and a phosphor represented by the following formula [I] or [II] is more preferable. Can be mentioned.

^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
(In Formula [I], M ¹ represents at least one type of activating element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb; ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn, L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the periodic table, and at least L , X, y, z, u, v, and w are 0.00001 ≦ x ≦ 3, 0 ≦ y ≦ 2.9999, 2.6 ≦ x + y + z ≦ 3, respectively. , 0 <u ≦ 11, 6 <v ≦ 25, and 0 <w ≦ 17.

M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
(In formula [II], M ³ represents an activating element, and e represents a positive number satisfying 0 <e ≦ 0.2.)

M ⁴ _f M ⁵ _g AlSiX ₃ [III]
(In the formula [III], M ⁴ represents an activator containing at least Eu, M ⁵ represents one or more elements selected from alkaline earth metal elements, and X consists of O and N One or more elements selected from the group are shown, and f and g are positive numbers satisfying 0 <f ≦ 0.2 and 0.9 ≦ f + g ≦ 1, respectively.

M ⁶ _h (Ca, Sr, Ba, Zn) _j Si ₅ X ₈ [IV]
(In Formula [IV], M ⁶ represents an activator element, X represents one or more elements selected from the group consisting of O and N, and h is a positive number satisfying 0 <h ≦ 0.4. And j is a numerical value satisfying 1-h <j ≦ 2-h.)

  Hereinafter, a suitable phosphor composition will be described for each of the formulas [I] to [IV].

[Description of Phosphor Represented by Formula [I]]
^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
In the above formula [I], M ¹ represents an activator element. Examples of M ¹ include at least one transition metal element or rare earth element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb. M ¹ may contain only one of these elements, or may have two or more of them in any combination and ratio.
Among these, Ce, Sm, Eu, Tm, or Yb, which are rare earth elements, are preferable elements. Among them, the M ¹ is preferably one containing at least Eu or Ce from the viewpoint of light emission quantum efficiency. Among them, in particular, those containing at least Eu are more preferable in terms of emission peak wavelength, and it is particularly preferable to use only Eu.

The activator element M ¹ is present as a divalent cation and / or a trivalent cation in the phosphor of the present invention. In this case, the activation element M ¹ is, it exists the percentage of divalent cations is high is preferable. For example, when M ¹ is Eu, the ratio of Eu ^{2+ to} the total Eu amount is usually 20 mol% or more, preferably 50 mol% or more, more preferably 80 mol% or more, and particularly preferably 90 mol% or more. .

In addition, the ratio of Eu < ²⁺ > in the total Eu contained in the phosphor of the present invention can be examined, for example, by measurement of an X-ray absorption fine structure (X-ray Absorption Fine Structure). That is, when the L3 absorption edge of Eu atom is measured, Eu ²⁺ and Eu ³⁺ show separate absorption peaks, and the ratio can be quantified from the area. The ratio of Eu ^{2+ in} the total Eu contained in the phosphor of the present invention can also be known by measuring electron spin resonance (ESR).

In the above formula [I], x is a numerical value in the range of 0.00001 or more and 3 or less. Among these, x is preferably 0.03 or more, more preferably 0.06 or more, still more preferably 0.12 or more, particularly preferably 0.18 or more, and particularly preferably 0.27 or more. On the other hand, since there is a case where the content of the activation element M ¹ is too large, concentration quenching occurs, preferably 1.5 or less, more preferably 1.2 or less, more preferably 0.9 or less, preferably preferably 0 0.7 or less, particularly preferably 0.45 or less.

Moreover, the phosphor of the present invention can substitute the position of Ba with Sr, Ca, Mg and / or Zn while maintaining the BSON phase crystal structure (described later). Therefore, in the above formula [I], M ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn. In this case, M ² is preferably Sr, Ca and / or Zn, more preferably Sr and / or Ca, and further preferably Sr. Ba and M ² may be partially substituted with these elements.
As the above-mentioned M ^2, it may contain only any one of these elements may be in having both of two or more kinds in any combination and in any ratio.

If the M ² containing Ca, the existing ratio of Ca to the total amount of Ba and Ca is preferably 50 mole% or less, more preferably 40 mol% or less, more preferably 30 mol% or less. If the Ca content is increased more than this, the emission wavelength may become longer and the emission intensity may be reduced.
When S ² is contained as M ² , the ratio of Sr to the total amount of Ba and Sr is preferably 70 mol% or less, more preferably 60 mol% or less, and still more preferably 50 mol% or less. If the amount of Sr increases more than this, the emission wavelength may become longer and the emission intensity may decrease.
Furthermore, when including Zn as ^{M 2,} the existing ratio of Zn to the total amount of Ba and Zn is preferably 60 mol% or less, more preferably 50 mol% or less, still more preferably not more than 40 mol%. If the Zn content is increased more than this, the emission wavelength may become longer and the emission intensity may be reduced.
Also, if it contains Mg as ^{M 2,} the existing ratio of Mg to the total amount of Ba and Mg, and preferably 30 mol% or less, more preferably 20 mol% or less, more preferably 10 mol% or less. If the amount of Mg increases more than this, the emission wavelength may become longer and the emission intensity may decrease.

Therefore, in the above formula [I], the amount of z may be set according to the type of the metal element M ^{2 to be} substituted and the amount of y. The specific value of z is usually 0 or more, preferably 1.5 or less, more preferably 1.2 or less, still more preferably 0.9 or less, particularly preferably 0.6 or less, and even more. Preferably it is 0.4 or less.

  In the above formula [I], y is a numerical value in the range of 0 ≦ y ≦ 2.99999. Among these, the phosphor of the present invention preferably contains Ba from the viewpoint of the stability of the crystal structure. Accordingly, in the above formula [I], y is preferably larger than 0, more preferably 0.9 or more, particularly preferably 1.2 or more, and 2 in relation to the content of the inactive agent element. Is preferably less than 2.999, more preferably 2.99 or less, even more preferably 2.98 or less, and particularly preferably 2.95 or less.

In the phosphor of the present invention, together with oxygen or nitrogen, Ba and M ² element is sometimes lacking. For this reason, in the above formula [I], the value of x + y + z may be less than 3, and x + y + z can usually take a value of 2.6 ≦ x + y + z ≦ 3, but ideally x + y + z = 3. is there. Here, when x + y + z is smaller than 2.6, there is a high possibility that the crystal structure cannot be maintained.

In the general formula [I], L is at least one selected from the group 4 metal elements of the periodic table such as Ti, Zr, and Hf, or the group 14 metal element of the periodic table such as Si and Ge. Represents a metal element. Note that L may contain only one of these metal elements, or may contain two or more of them in any combination and ratio. However, at least a part of L is Si element. Of these, L is preferably Ti, Zr, Hf, Si or Ge, more preferably Si or Ge, and particularly preferably Si.
Here, L is a metal element that can be a trivalent cation such as B, Al, and Ga, as long as it does not adversely affect the performance of the phosphor in terms of the charge balance of the phosphor crystal. It may be mixed. The mixing amount is usually 10 atomic% or less, preferably 5 atomic% or less with respect to L.

  In the above general formula [I], u is usually 11 or less, preferably 9 or less, more preferably 7 or less, and is a value greater than 0, preferably 3 or more, more preferably 5 or more. .

  The amounts of O ions and N ions are represented by numerical values v and w in the general formula [I]. Specifically, in the above general formula (I), v is usually a value greater than 6, preferably greater than 7, more preferably greater than 8, even more preferably greater than 9, and particularly preferably greater than 11. It is usually 25 or less, preferably less than 20, more preferably less than 15, and still more preferably less than 13.

  Further, since the phosphor of the present invention is an oxynitride, N is an essential component. Therefore, in the general formula (I), w is a numerical value greater than 0. Moreover, w is a numerical value of 17 or less normally, Preferably it is smaller than 10, More preferably, it is smaller than 4, More preferably, it is a numerical value smaller than 2.4.

  Therefore, from the above viewpoint, in the general formula [I], u, v, and w are preferably 5 ≦ u ≦ 7, 9 <v <15, and 0 <w <4, respectively, 5 ≦ u It is particularly preferable that ≦ 7, 11 <v <13, and 0 <w <2.4. Thereby, the light emission intensity can be increased.

Here, the O and N sites may be monovalent or divalent, such as S or halogen atoms, as long as they do not affect the performance of the phosphor in terms of the charge balance of the phosphor crystal. The element which can become an anion of may be mixed. The mixing amount is usually 10 atomic% or less, preferably 5 atomic% or less with respect to the total amount of O and N.
In particular, the halogen element is mixed not only from the raw material impurities but also from the flux used during production. In this case, the halogen atom is usually contained in the phosphor in an amount of 1 ppm or more, and the upper limit depends on the washing method after firing the phosphor, but is usually 1000 ppm or less, preferably 500 ppm or less, more preferably 300 ppm or less. contains.

In the phosphor of the present invention, it is preferable that the ratio of oxygen atoms to the metal elements such as (M ¹ + Ba + M ² ) and L is larger than the ratio of nitrogen atoms. Accordingly, the amount of nitrogen atoms relative to the amount of oxygen atoms (N / O) is preferably 70 mol% or less, more preferably 50 mol% or less, still more preferably 30 mol% or less, and particularly preferably less than 20 mol%. is there. Moreover, as a minimum, it is larger than 0 mol% normally, Preferably it is 5 mol% or more, More preferably, it is 10 mol% or more.

[Description of Phosphor represented by Formula [I ′]]
By the way, in the phosphor represented by the formula [I], the phosphor represented by the following general formula [I ′] in which a part of Ba and L are respectively substituted with Ln and Al is also included.
M ¹ _χ (Ba, Ln) _a (L, Al) _b O _c N _d [I ′]
(In Formula [I ′], M ¹ represents at least one type of activating element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb. Ln represents one or more elements selected from the group consisting of La, Ce, Pr, Nd, Y and Gd, and L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the periodic table. , At least part of L is Si element, and χ, a, b, c, and d are 0.00001 ≦ χ ≦ 0.4, 2.6 ≦ a ≦ 2.99999, 5 ≦, respectively. (Values in the range of b ≦ 7, 11 <c <13, and 0 <d <2.4 are shown.)

In the formula [I ′], M ¹ and L are the same as those in the formula [I]. Among them, regarding L, the ratio of Al to the total of L and Al is usually 20 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, and even more preferably 5 mol% or less. Yes, and usually a value greater than zero.

In the formula [I ′], Ln represents one or more elements selected from the group consisting of La, Ce, Pr, Nd, Y, and Gd. Ln may contain only one of these elements, or may have two or more of them in any combination and ratio.
Among them, it is preferable that at least one element selected from the group consisting of La, Y, and Gd is contained, and it is more preferable that Y is contained.

The sum of the amounts of La, Y and Gd with respect to the total amount of Ln usually occupies 50 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more, and even more preferably 95 mol%. It accounts for more than mol%.
In the above formula [I ′], the ratio of Ln to the total amount of Ba and Ln is usually 20 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, and further preferably 5 mol. % Or less, and usually a value greater than zero.

  In the formula [I ′], χ is a numerical value in the range of 0.00001 ≦ χ ≦ 0.4, a is a numerical value in the range of 2.6 ≦ a ≦ 2.9999, and b is 5 ≦ b. ≦ 7 is a numerical value, c is a numerical value in a range of 11 <c <13, and d is a numerical value in a range of 0 <d <2.4.

Usually, the phosphor represented by the above formula [I ′] can be obtained as a solid solution of the phosphor represented by the formula [I] and langasite.
Here, the langasite means La ₃ Si ₃ Al ₃ O ₁₂ N ₂ .

Further, when the phosphor represented by the formula [I ′] is formed from the solid solution, the solid solution ratio between the phosphor represented by the formula [I] and the langasite is the fluorescence represented by the formula [I]. The molar ratio of langasite to the total number of moles of body and langasite is usually 0.01 mol% or more, preferably 0.1 mol% or more, more preferably 1 mol% or more, and usually 30 mol% or less. , Preferably 20 mol% or less, more preferably 10 mol% or less. If there is too much langasite, BaAl ₂ Si ₂ O ₈ may be generated as an impurity phase.

Specific examples of preferred compositions of the phosphor represented by the formula [I] are given below. However, the composition of the phosphor represented by the formula [I] is not limited to the following examples.
Preferred examples of the phosphor represented by the formula [I] include (Ca, Sr, Ba) ₃ (Si, Ge) ₆ O ₁₂ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba). ) ₃ (Si, Ge) ₆ O ₉ N ₄ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₆ O ₃ N ₈ : (Eu, Ce, Mn), (Ca , Sr, Ba) ₃ (Si, Ge) ₇ O ₁₂ N _8/3 : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₂ N _14/3 : (Eu , Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₂ N ₆ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) _28/3 O _{12 N 22/3: (Eu, Ce} , Mn), (Ca, Sr, Ba) 3 (Si, Ge) 29/3 O 12 N _{6/3: (Eu, Ce, Mn} ), (Ca, Sr, Ba) 3 (Si, Ge) 6.5 O 13 N 2: (Eu, Ce, Mn), (Ca, Sr, Ba) 3 ( Si, Ge) ₇ O ₁₄ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₈ O ₁₆ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₉ O ₁₈ N ₂ : (Eu, Ce, Mn), (Ca, Sr, Ba) ₃ (Si, Ge) ₁₀ O ₂₀ N ₂ : (Eu, Ce, Mn), ( Ca, Sr, Ba) ₃ (Si, Ge) ₁₁ O ₂₂ N ₂ : (Eu, Ce, Mn) and the like. Among these, more preferable specific examples include Ba ₃ Si ₆ O ₁₂ N ₂ : Eu, Ba ₃ Si ₆ O ₉ N ₄ : Eu, Ba ₃ Si ₆ O ₃ N ₈ : Eu, Ba ₃ Si ₇ O ₁₂ N _{8 / 3: Eu, Ba 3 Si} 8 O 12 N 14/3: Eu, Ba 3 Si 8 O 12 N 6: Eu, Ba 3 Si 28/3 O 12 N 22/3: Eu, Ba 3 Si 29/3 O ₁₂ N _26/3 : Eu, Ba ₃ Si _6.5 O ₁₃ N ₂ : Eu, Ba ₃ Si ₇ O ₁₄ N ₂ : Eu, Ba ₃ Si ₈ O ₁₆ N ₂ : Eu, Ba ₃ Si ₉ O _{18 N 2: Eu, Ba 3 Si} 10 O 20 N 2: Eu, Ba 3 Si 11 O 22 N 2: Eu, Ba 3 Si 6 O 12 N 2: Eu, Mn, Ba 3 Si 6 O 9 N 4: Eu , Mn, Ba ₃ Si ₆ O _{3 N 8: Eu, Mn,} Ba 3 Si 7 O 12 N 8/3: Eu, Mn, Ba 3 Si 8 O 12 N 14/3: Eu, Mn, Ba 3 Si 8 O 12 N 6: Eu, Mn _{, Ba 3 Si 28/3 O 12 N} 22/3: Eu, Mn, Ba 3 Si 29/3 O 12 N 26/3: Eu, Mn, Ba 3 Si 6.5 O 13 N 2: Eu, Mn, _{Ba 3 Si 7 O 14 N 2} : Eu, Mn, Ba 3 Si 8 O 16 N 2: Eu, Mn, Ba 3 Si 9 O 18 N 2: Eu, Mn, Ba 3 Si 10 O 20 N 2: Eu, _{Mn, Ba 3 Si 11 O 22} N 2: Eu, Mn, Ba 3 Si 6 O 12 N 2: Ce, Ba 3 Si 6 O 9 N 4: Ce, Ba 3 Si 6 O 3 N 8: Ce, Ba 3 _{Si 7 O 12 N 8/3: Ce} , Ba 3 Si ₈ O ₁₂ N _14/3 : Ce, Ba ₃ Si ₈ O ₁₂ N ₆ : Ce, Ba ₃ Si _28/3 O ₁₂ N _22/3 : Ce, Ba ₃ Si _29/3 O ₁₂ N _26/3 : Ce, Ba ₃ Si _6.5 O ₁₃ N ₂ : Ce, Ba ₃ Si ₇ O ₁₄ N ₂ : Ce, Ba ₃ Si ₈ O ₁₆ N ₂ : Ce, Ba ₃ Si ₉ O ₁₈ N ₂ : Ce, Ba ₃ Examples thereof include Si ₁₀ O ₂₀ N ₂ : Ce, Ba ₃ Si ₁₁ O ₂₂ N ₂ : Ce.

[Description of Phosphor Represented by Formula [II]]
M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
In the above formula [II], M ³ represents an activator element. As an example of M ³ , the same metal element as M ^{1 in the} above formula [I] can be mentioned.
In the formula [II], e represents a numerical value greater than 0, preferably 0.001 or more, more preferably 0.005 or more, and the upper limit is 0.2 or less, more preferably Represents a numerical value of 0.15 or less.

[Description of Phosphor Represented by Formula [III]]
M ⁴ _f M ⁵ _g AlSiX ₃ [III]
In the above formula [III], M ⁴ represents an activation element containing at least Eu. Examples of elements other than Eu include at least one transition element or rare earth element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm, and Yb. Here, as M ^4, as long as at least Eu is contained, any one of these elements may be contained, and two or more kinds are combined in any combination and ratio. Also good. Among them, it is desirable that Eu is usually 50 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more, further preferably 95 mol% or more with respect to the total amount of M ⁴ . Among them, it is particularly preferred to use as M ⁴ Eu only.

The activator element M ⁴ is present as a divalent cation and / or a trivalent cation in the phosphor of the present invention. At this time, the activation element M ⁴ preferably has a high proportion of divalent cations. For example, when M ⁴ is Eu, the ratio of Eu ^{2+ to} the total Eu amount is usually 20 mol% or more, preferably 50 mol% or more, more preferably 80 mol% or more, and particularly preferably 90 mol% or more. .

The ratio of Eu ^{2+ in} the total Eu contained in the phosphor of the present invention can be measured by the method described in [Description of phosphor represented by formula [I]].

  Moreover, in the said general formula [III], f is a numerical value larger than 0 and 0.2 or less. Among these, f is preferably 0.001 or more, more preferably 0.005 or more, from the viewpoint of obtaining a phosphor having a longer wavelength as an emission peak. On the other hand, from the viewpoint of lowering the emission intensity, it is preferably 0.05 or less, more preferably 0.045 or less, still more preferably 0.04 or less, and particularly preferably 0.035 or less.

The M ⁵ represents one or more elements selected from alkaline earth metal elements. Examples thereof include Mg, Ca, Sr, Ba and the like. Among these, Mg, Ca and Sr are preferable, Mg and Ca are more preferable, and Ca is particularly preferable.
As the above-mentioned M ^5, it may contain only one kind, or two or more kinds may of them together in any combination and in any ratio, but preferably contains at least Ca. Among them, Ca with respect to the total ^{M 5} amount of usually 50 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably account for at least 95 mol%. Among them, it is particularly preferred to use as M ⁵ Ca only.

In the above formula [III], g represents a positive number of 0.7 or more and 1 or less. In the phosphor of the present invention represented by the formula [III], f + g = 1 theoretically. On the other hand, together with oxygen or nitrogen, sometimes M ⁵ elements are missing. For this reason, in the above-mentioned formula [III], the value of f + g may be less than 1, and usually 0.9 ≦ f + g ≦ 1.

  In the above formula [III], X is an element selected from the group consisting of O or N. Any one of these elements may be contained, or two or more of these elements may be contained in any combination and ratio. In addition to the above, a part of halogen atoms may be contained as long as the performance is not affected. The content thereof is usually 1 mol% or less with respect to the total X amount.

  Among these, X preferably contains at least N, and N is usually 90 mol% or more, preferably 97 mol% or more, more preferably 99 mol% or more, and still more preferably based on the total amount of X. It is preferable to occupy 99.5 mol% or more. Among these, it is particularly preferable to use only N as X.

[Description of the phosphor represented by the formula [IV]]
M ⁶ _h (Mg, Ca, Sr, Ba) _j Si ₅ X ₈ [IV]
In the above formula [IV], M ⁶ represents an activator element. Examples of M ^6, include the same metal element as M ¹ in the formula [I].
In Formula [IV], X is the same as in Formula [III].
In the above formula [IV], h is a numerical value greater than 0, preferably 0.001 or more, more preferably 0.005 or more, and further preferably 0.01 or more. Is 0.4 or less, preferably 0.2 or less, more preferably 0.1 or less.
J represents a numerical value satisfying 1−h <j ≦ 2-h.

[2-2. Characteristics of phosphor]
When the phosphor of the present invention is a phosphor represented by the above formulas [I] to [IV], the characteristics thereof are brighter and the quantum efficiency is higher than the known phosphors of the same composition. high.

Here, the object color means a color when light is reflected by the object, and can be represented by the L ^* a ^* b ^* color system (see JISZ8113). In the present invention, an object to be measured (that is, a phosphor) is irradiated with a predetermined light source (white light source; for example, standard light D65 can be used), and the obtained reflected light is dispersed by a filter. , L ^* value, a ^* value, b ^* value. The value varies depending on the color of each phosphor. However, as the L ^* value is larger, the a ^* and b ^* values tend to become clearer as the absolute value is larger.

The L ^* value in the phosphor object color may exceed 100 because the light emitted by the irradiation light source may be superimposed on the reflected light, but is usually 110 or less. The object color of the phosphor of the present invention can be measured by using, for example, a commercially available object color measuring device (for example, CR-300 manufactured by Minolta).

The quantum efficiency can be obtained as follows.
(Measurement method of absorption efficiency, internal quantum efficiency, and external quantum efficiency)
A method for obtaining the absorption efficiency αq, internal quantum efficiency ηi, and external quantum efficiency ηo of the phosphor will be described below.

  First, a phosphor sample to be measured (for example, a powder form) is packed in a cell with a sufficiently smooth surface so that measurement accuracy is maintained, and is attached to a condenser such as an integrating sphere. The use of a condenser such as an integrating sphere makes it possible to count all photons reflected by the phosphor sample and photons emitted from the phosphor sample due to the fluorescence phenomenon, that is, not counted but out of the measurement system. This is to eliminate the photons that fly away.

  A light-emitting source for exciting the phosphor is attached to the condenser such as an integrating sphere. This light source is, for example, an Xe lamp or the like, and is adjusted using a filter, a monochromator (diffraction grating spectrometer), or the like so that the emission peak wavelength is monochromatic light having a wavelength of 405 nm or 455 nm, for example. The phosphor sample to be measured is irradiated with light from the light emission source whose emission peak wavelength is adjusted, and a spectrum including light emission (fluorescence) and reflected light is measured by a spectroscopic measurement device such as MCPD2000, MCPD7000 manufactured by Otsuka Electronics Co., Ltd. Use to measure. The spectrum measured here is actually reflected light that has not been absorbed by the phosphor among the light from the excitation light source (hereinafter simply referred to as excitation light), and the phosphor absorbs the excitation light. Thus, light of another wavelength (fluorescence) emitted by the fluorescence phenomenon is included. That is, the region near the excitation light corresponds to the reflection spectrum, and the longer wavelength region corresponds to the fluorescence spectrum (sometimes referred to herein as the emission spectrum).

The absorption efficiency αq is a value obtained by dividing the number of photons N _abs of the excitation light absorbed by the phosphor sample by the total number of photons N of the excitation light.

First, the total photon number N of the latter excitation light is obtained as follows. That is, a reflector having a reflectance R of almost 100% with respect to the excitation light, such as a “Spectralon” manufactured by Labsphere (having a reflectance R of 98% with respect to excitation light having a wavelength of 450 nm), is measured. A target is attached to a condenser such as the integrating sphere described above in the same arrangement as the phosphor sample, and the reflection spectrum I _ref (λ) is measured using the spectrometer. The numerical value of the following (formula 1) obtained from the reflection spectrum I _ref (λ) is proportional to N.

Here, the integration interval may be substantially performed only in the interval where I _ref (λ) has a significant value.
The number of photons N _abs of the excitation light absorbed by the phosphor sample is proportional to the amount obtained by the following (formula 2).

Here, I (λ) is a reflection spectrum when a phosphor sample for which the absorption efficiency αq is to be obtained is attached. The integration interval of (Expression 2) is the same as the integration interval defined in (Expression 1). By limiting the integration interval in this way, the second term of (Equation 2) corresponds to the number of photons generated when the phosphor sample to be measured reflects excitation light, that is, as the measurement target. Among all photons generated from the phosphor sample, the photons derived from the fluorescence phenomenon are excluded. Since the actual spectrum measurement value is generally obtained as digital data divided by a certain finite bandwidth with respect to λ, the integrals of (Equation 1) and (Equation 2) are obtained by the sum based on the bandwidth.
From the above, αq = N _abs / N = (Expression 2) / (Expression 1).

Next, a method for obtaining the internal quantum efficiency ηi will be described. ηi is a value obtained by dividing the number N _PL of photons derived from the fluorescence phenomenon by the number N _abs of photons absorbed by the phosphor sample.
Here, _NPL is proportional to the amount obtained by the following (formula 3).

At this time, the integration interval is limited to the wavelength range of photons derived from the fluorescence phenomenon of the phosphor sample. This is because the contribution of photons reflected from the phosphor sample is removed from I (λ). Specifically, the lower limit of the integration interval of (Equation 3) is the upper end of the integration interval of (Equation 1), and the upper limit is a range necessary and sufficient to include photons derived from fluorescence.
As described above, the internal quantum efficiency ηi is obtained as ηi = (Expression 3) / (Expression 2).

The integration from the spectrum that has become digital data is the same as the case where the absorption efficiency αq is obtained.
Then, the external quantum efficiency ηo is obtained by taking the product of the absorption efficiency αq and the internal quantum efficiency ηi obtained as described above. Or it can also obtain | require from the relationship of (eta) == (Formula 3) / (Formula 1). ηo is a value obtained by dividing the number N _PL of photons derived from fluorescence by the total number N of photons of excitation light.
Hereinafter, the characteristics of the phosphors represented by the above formulas [I] to [IV] will be described.

[2-2-1. Phosphor represented by formula [I]]
(Characteristics related to excitation spectrum)
The phosphor of the present invention represented by the formula [I] is preferably excitable with light in a wavelength range of 200 nm to 500 nm. In particular, in order to suitably use a semiconductor element or the like as a first light emitter and use the light as a phosphor excitation light source, for example, light in a blue region (wavelength range: 420 nm to 500 nm) and It is preferable that excitation is possible with light in the near ultraviolet region (wavelength range: 300 nm to 420 nm).

Further, the phosphor of the present invention represented by the formula [I] is in the emission spectrum diagram when irradiated with light having a wavelength of 410 nm with respect to the emission peak intensity value in the emission spectrum diagram when irradiated with light having a wavelength of 390 nm. The ratio of the emission peak intensity value is usually 90% or more.
The emission spectrum can be measured by exciting the phosphor with light having a wavelength of 390 nm or 410 nm extracted from the light source by a diffraction grating as described above, and the emission peak intensity is obtained from the measured emission spectrum. When two or more emission peaks appear, it is preferable that the intensity of the maximum emission peak satisfies the above conditions.

(Characteristics related to emission spectrum)
In view of the use as a green phosphor, the phosphor of the present invention represented by the formula [I] preferably has the following characteristics when an emission spectrum is measured when excited with light having a wavelength of 400 nm.

  First, the phosphor of the present invention represented by the formula [I] preferably has a peak wavelength λp (nm) in the above-described emission spectrum of around 525 nm, specifically, usually larger than 500 nm, especially 510 nm or more, Further, it is preferably 515 nm or more, and is usually 550 nm or less, particularly 540 nm or less, and more preferably 535 nm or less. If this emission peak wavelength λp is too short, it tends to be bluish, while if it is too long, it tends to be yellowish, and there is a possibility that the characteristics as green light will deteriorate.

  In addition, the phosphor of the present invention represented by the formula [I] has a full width at half maximum (hereinafter, abbreviated as “FWHM” where appropriate) in the above-described emission spectrum, which is usually larger than 40 nm. In particular, it is preferably 50 nm or more, more preferably 60 nm or more, and usually less than 90 nm, particularly 80 nm or less, and more preferably 75 nm or less. If the half-value width FWHM is too narrow, the color rendering property may be lowered when the illumination is used because the luminance is reduced. If the half-width FWHM is too wide, the color is not suitable for use in an image display device such as a liquid crystal display. Since the purity is lowered, the color reproduction range of the image display apparatus may be narrowed.

  In order to excite the phosphor of the present invention represented by the formula [I] with light having a wavelength of 400 nm, for example, a GaN-based LED can be used. In addition, the measurement of the emission spectrum of the phosphor of the present invention represented by the formula [I] and the calculation of the emission peak wavelength, peak relative intensity and peak half-value width can be performed by, for example, using a 150 W xenon lamp as an excitation light source, Can be performed using a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics).

(Luminescent color)
As for the luminescent color of the phosphor of the present invention represented by the formula [I], x is usually 0.100 or more, preferably 0.150 or more, more preferably 0.200 or more as chromaticity coordinate values based on JIS Z8701. In addition, it is usually 0.400 or less, preferably 0.380 or less, more preferably 0.360 or less, still more preferably 0.3 or less, and particularly preferably 0.29 or less. Further, y is usually 0.480 or more, preferably 0.490 or more, more preferably 0.495 or more, further preferably 0.5 or more, particularly preferably 0.55 or more, particularly preferably 0.6 or more. In addition, it is desirable that the range is usually 0.670 or less, preferably 0.660 or less, more preferably 0.655 or less. The phosphor of the present invention represented by the formula [I] emits light in the above range while maintaining the luminance, for example, by changing the amounts of M ¹ element and M ² source element and firing in the presence of flux. Can be changed.

(Object color)
The phosphor of the present invention represented by the formula [I] is characterized in that the object color is clearer than the conventional phosphor having the same composition. Specifically, when the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value is 97 or more, the a ^* value is −21 or less, and the b ^* value is 35 or more. It is preferable.
The L ^* value indicates that a larger numerical value indicates a clearer color, preferably 100 or more, and more preferably 103 or more.
The a ^* value indicates that a smaller numerical value indicates a greener and clearer color, more preferably −23 or less, and further preferably −25 or less. Moreover, it becomes a numerical value of -60 or more normally.
The b ^* value indicates that a larger numerical value indicates a brighter color as green, and is preferably 35 or more, and more preferably 40 or more. On the other hand, the upper limit of the b ^* value is theoretically 200 or less, but is usually preferably 120 or less. This is because if the b ^* value is too large, the emission wavelength may shift to the longer wavelength side and the luminance may decrease.

(Quantum efficiency)
The phosphor of the present invention represented by the formula [I] has a higher external quantum efficiency than conventional phosphors having the same composition. Specifically, the external quantum efficiency is usually 0.35 or more, preferably 0.40 or more, more preferably 0.45 or more, and particularly preferably 0.50 or more. In order to design a light emitting device with high emission intensity, the higher the external quantum efficiency, the better.

  In addition, the internal quantum efficiency of the phosphor of the present invention represented by the formula [I] is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more, further preferably 0.75 or more, particularly Preferably it is 0.8 or more. Here, the internal quantum efficiency means the ratio of the number of photons emitted to the number of photons of excitation light absorbed by the phosphor. If the internal quantum efficiency is low, the light emission efficiency tends to decrease.

  Furthermore, the phosphor of the present invention represented by the formula [I] is more preferable as its absorption efficiency is higher. The value is usually 0.5 or more, preferably 0.6 or more, more preferably 0.65 or more, and further preferably 0.7 or more. The external quantum efficiency is determined by the product of the internal quantum efficiency and the absorption efficiency. In order to have a high external quantum efficiency, it is preferable that the absorption efficiency is also high.

(Temperature characteristics)
Furthermore, the phosphor of the present invention represented by the formula [I] has excellent temperature characteristics. Specifically, the ratio of the emission peak intensity value in the emission spectrum diagram at 150 ° C. to the emission peak intensity value in the emission spectrum diagram at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 55% or more. And preferably 60% or more, particularly preferably 70% or more.
Further, since the emission intensity of ordinary phosphors decreases with increasing temperature, it is unlikely that the ratio exceeds 100%, but it may exceed 100% for some reason. However, if it exceeds 150%, the color shift tends to occur due to a temperature change.
The ratio of the emission peak intensity value in the emission spectrum diagram at 100 ° C. to the emission peak intensity value in the emission spectrum diagram at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 70% or more, Preferably it is 75% or more, Most preferably, it is 80% or more.

The phosphor of the present invention represented by the formula [I] is excellent not only in terms of the emission peak intensity but also in terms of luminance. Specifically, the ratio of the luminance at 150 ° C. to the luminance at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 55% or more, preferably 60% or more, particularly preferably 70% or more. is there.
Further, the ratio of the luminance at 100 ° C. to the luminance at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 70% or more, preferably 75% or more, and particularly preferably 80% or more.

The phosphor of the present invention represented by the formula [I] has a small change in the value of the emission peak wavelength accompanying a change in temperature. Specifically, when the emission peak wavelength value at 20 ° C. is λ ₂₀ , the emission peak wavelength value at 150 ° C. is usually λ ₂₀ −10 nm or more, preferably λ ₂₀ −5 nm or more, more preferably λ ₂₀ -3 nm or more, usually λ ₂₀ +10 nm or less, preferably λ ₂₀ +5 nm or less, more preferably λ ₂₀ +3 nm or less.

Further, the phosphor of the present invention represented by the formula [I] has a small change with respect to the emission color. Specifically, as chromaticity coordinate values (CIEx, CIEy) based on JIS Z8701, when the chromaticity coordinate values X and Y at 20 ° C. are X ₂₀ and Y ₂₀ , respectively, the X value at 150 ° C. is usually X It is in the range of ₂₀ −0.03 or more and usually X ₂₀ +0.03 or less, and the Y value at 150 ° C. is usually in the range of Y ₂₀ −0.03 or more and usually Y ₂₀ +0.03 or less.

In the case of measuring the temperature characteristics, for example, an MCPD7000 multi-channel spectrum measuring device manufactured by Otsuka Electronics as an emission spectrum measuring device, a stage having a cooling mechanism by a Peltier element and a heating mechanism by a heater, and a 150 W xenon lamp as a light source are provided. Using the apparatus, measurement can be performed as follows.
A cell containing a phosphor sample is placed on the stage, and the temperature is changed in the range of 20 ° C to 150 ° C. It is confirmed that the surface temperature of the phosphor is constant at 20 ° C. or 150 ° C. Next, the emission spectrum is measured by exciting the phosphor with light having a wavelength of 455 nm extracted from the light source by the diffraction grating. The emission peak intensity and luminance are obtained from the measured emission spectrum. Here, as the measured value of the surface temperature on the excitation light irradiation side of the phosphor, a value corrected using the measured temperature value by the radiation thermometer and the thermocouple is used. Further, when two or more emission peaks appear, it is preferable that the intensity of the maximum emission peak satisfies the above conditions.

  In addition, as a method for measuring the chromaticity coordinate, a wavelength range of 380 nm to 800 nm (excitation wavelength of 340 nm), 430 nm to 800 nm (excitation wavelength of 400 nm), or 480 nm to 800 nm (excitation wavelength of 455 nm) of an emission spectrum is used. From the above data, chromaticity coordinates CIEx and CIEy in the XYZ color system defined by JIS Z8701 may be calculated by a method according to JIS Z8724.

(durability)
The phosphor of the present invention represented by the formula [I] is usually 1000 ° C. or higher, preferably 1200 ° C. or higher, more preferably 1300 ° C. or higher, and further preferably 1500 in a durability test in which heating is performed for 2 hours in a nitrogen atmosphere. Even if it is 1700C or more, it is not decomposed.

  Furthermore, the phosphor of the present invention represented by the formula [I] is usually a phosphor having excellent durability. For this reason, the phosphor of the present invention represented by the formula [I] has a property that its emission intensity is difficult to decrease even when used for a long time. As a specific range, the phosphor of the present invention represented by the formula [I] is usually 200 hours or more, preferably 500 hours or more, in a durability test in an environment where the temperature is 85 ° C. and the relative humidity is 85%. More preferably, it is stable for 600 hours or longer, particularly preferably 800 hours or longer. In this case, the longer the stable time, the better. However, 1000 hours is usually sufficient. Here, “stable” means that the ratio of the emission intensity after the durability test to the emission intensity before the durability test is 50% or more. The durability can be measured by energizing 20 mA in an environment with a temperature of 85 ° C. and a relative humidity of 85% using an LED aging system manufactured by Yamakatsu Electronics Co., Ltd. You may go.

Further, among the phosphors of the present invention represented by the formula [I], the phosphor obtained through the reheating step is dispersed in a silicone resin at a concentration of 6% by weight, and the temperature is 85 ° C., The chromaticity coordinate CIEy value based on JIS Z 8701 after energizing for 500 hours at an electric current density of 255 mA / mm ² and a light emission output of 0.25 to 0.35 W / mm ² in an environment of 85% relative humidity is The value is usually within a range of ± 30%, preferably within a range of ± 25%, more preferably within a range of ± 20 with respect to the chromaticity coordinate CIEy value based on JIS Z 8701.

Further, the luminance maintenance rate of light emission at the time when 100 hours have elapsed from the start of excitation light irradiation is usually 83% or more, preferably 85% or more, more preferably 90% or more, relative to the light emission at the start of excitation light irradiation. is there.
For example, C460EZ290 (manufactured by Cree, wavelength range of 455 nm to 457.4 nm) may be energized with 20 mA as the above-described excitation light with current density and light emission output, and the phosphor may be irradiated with excitation light. Moreover, as a silicone resin which disperse | distributes fluorescent substance at this time, Shin-Etsu Chemical Co., Ltd. SCR1101 is mentioned.

  The reason why the phosphor of the present invention represented by the formula [I] can exhibit excellent durability as described above by having the reheating step is not clear, but according to the study by the present inventors, This is presumably because the number of lattice defects trapped by the electrons excited by is reduced.

(Crystal structure)
The phosphor of the present invention represented by the formula [I] usually contains a BSON phase (also referred to as a Ba ₃ Si ₆ O ₁₂ N ₂ phase) which is a crystal phase defined below.
BSON phase:
A crystal phase in which a diffraction peak is observed in a diffraction angle (2θ) range of 26.9 to 28.2 ° (R0) in an X-ray diffraction measurement using a CuKα X-ray source, and the diffraction peak (P0) Is a reference diffraction peak, and five diffraction peaks derived from the Bragg angle (θ0) of P0 (excluding diffraction peaks in the angle range of 20.9 ° to 22.9 °) are sequentially set from the low angle side to P1. , P2, P3, P4, and P5, and R1, R2, R3, R4, and R5 are R1, R2, R3, R4, and R5, and R1, R2, R3, R4, and R5 are R1 = R1s to R1e, R2 = R2s to R2e, R3 = R3s to R3e, R4 = R4s to R4e, R5 = R5s to R5e. Diffraction pea And at least one of P0, P1, P2, P3, P4 and P5, the intensity of P0 is the diffraction peak height ratio with respect to the height of the diffraction peak with the highest diffraction peak height. A crystal phase having an intensity of 20% or more and at least one peak intensity of P1, P2, P3, P4 or P5 is 5% or more, preferably 9% or more in terms of a diffraction peak height ratio.

Here, when there are two or more diffraction peaks in each angular range of the angular ranges R0, R1, R2, R3, R4, and R5, the peak having the highest peak intensity among these is P0, P1, Let P2, P3, P4 and P5.
R1s, R2s, R3s, R4s and R5s are the start angles of R1, R2, R3, R4 and R5, respectively. R1e, R2e, R3e, R4e and R5e are the ends of R1, R2, R3, R4 and R5, respectively. An angle is shown, and the following angles are shown.
R1s: 2 × arcsin {sin (θ0) / (1.994 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (1.994 × 0.985)}
R2s: 2 × arcsin {sin (θ0) / (1.412 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (1.412 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (1.155 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (1.155 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.894 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.894 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.756 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.756 × 0.985)}

  In addition, the phosphor of the present invention represented by the formula [I] is a cristobalite, α-silicon nitride, β-silicon nitride, or the like that is a single crystal form of silicon dioxide in X-ray diffraction measurement using a CuKα X-ray source. The impurity phase may be contained. The content of these impurities can be known by X-ray diffraction measurement using a CuKα X-ray source. That is, the strongest peak intensity of the impurity phase in the X-ray diffraction measurement result is usually 40% or less, preferably 30% or less with respect to the strongest peak intensity of the P0, P1, P2, P3, P4 and P5. More preferably, it is 20% or less, and more preferably 10% or less. In particular, it is preferable that the peak of the impurity phase is not observed and the BSON phase exists as a single phase. Thereby, the light emission intensity can be increased.

(Solubility)
The phosphor of the present invention represented by the formula [I] usually has the property of hardly dissolving in solvents such as acids. Preferably, it is insoluble in water and / or 1N hydrochloric acid.

[2-2-2. Phosphor represented by Formula [II]
(Characteristics related to emission spectrum)
In the phosphor of the present invention represented by the formula [II], the emission peak wavelength varies in the blue or green to yellow region depending on the type of alkaline earth metal used, but in view of the use as a phosphor. When the emission spectrum is measured when excited with light having a wavelength of 400 nm, it preferably has the following characteristics.

  First, the phosphor of the present invention represented by the formula [II] has a peak wavelength λp (nm) in the emission spectrum described above when the mole number of Ba is 70% or more in (Ca, Sr, Ba). However, it is usually 410 nm or more, particularly 420 nm or more, more preferably 430 nm or more, and usually 480 nm or less, particularly preferably 470 nm or less. On the other hand, when the molar ratio of Ba in (Ca, Sr, Ba) is less than 70%, the peak wavelength λp (nm) in the above-mentioned emission spectrum is usually larger than 500 nm, preferably more than 510 nm. It is preferably 515 nm or more, and usually 600 nm or less, preferably 590 nm or less, more preferably 580 nm or less.

  In addition, in the phosphor of the present invention represented by the formula [II], the FWHM of the emission peak in the above emission spectrum is usually larger than 40 nm, preferably 50 nm or more, more preferably 60 nm or more, It is preferably 120 nm or less, particularly 110 nm or less, and more preferably 100 nm or less. If the half-value width FWHM is too narrow, the color rendering property may be lowered when the illumination is used because the luminance is reduced. If the half-width FWHM is too wide, the color is not suitable for use in an image display device such as a liquid crystal display. Since the purity is lowered, the color reproduction range of the image display apparatus may be narrowed.

  The phosphor of the present invention represented by the formula [II] was measured for the emission spectrum and its emission peak wavelength in the same manner as described in the section of the phosphor of the present invention represented by the formula [I]. The peak relative intensity and the peak half-value width can be calculated.

(Luminescent color)
The emission color of the phosphor of the present invention represented by the formula [II] is, as chromaticity coordinate values based on JIS Z8701, in the case of blue emission, x is usually not more than 0.3, preferably not more than 0.25. Preferably it is 0.2 or less, and y is usually 0.6 or less, preferably 0.5 or less, more preferably 0.4 or less. In the case of green to yellow light emission, x is usually 0.2 or more and 0.65 or less, and y is usually 0.35 or more and 0.7 or less.

(Object color)
The phosphor of the present invention represented by the formula [II] is characterized in that the object color is clearer than the conventional phosphor having the same composition. Specifically, when the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value satisfies 103 or more, the a ^* value is −23 or less, and the b ^* value is 63 or more. It is preferable.
The L ^* value indicates that the larger the numerical value, the clearer the color, and usually 70 or more, preferably 80 or more, more preferably 90 or more, and further preferably 100 or more. Yes, preferably 103 or more, particularly preferably 105 or more.
The a ^* value indicates that a smaller numerical value indicates a greener and clearer color, and is usually −20 or less, preferably −23 or less, and more preferably −24 or less. Moreover, it becomes a numerical value of -60 or more normally.
The b ^* value indicates that the larger the numerical value is, the brighter the color is green. Usually, it is 35 or more, preferably 45 or more, more preferably 63 or more, and particularly preferably 70 or more. On the other hand, the upper limit of the b ^* value is theoretically 200 or less, but is usually preferably 120 or less. This is because if the b ^* value is too large, the emission wavelength may shift to the longer wavelength side and the luminance may decrease.

(Quantum efficiency)
The phosphor of the present invention represented by the formula [II] has an external quantum efficiency higher than that of a conventional phosphor having the same composition. Specifically, the external quantum efficiency is usually 0.57 or more, more preferably 0.60 or more, and further preferably 0.62 or more. In order to design a light emitting device with high emission intensity, the higher the external quantum efficiency, the better.

  Further, the internal quantum efficiency of the phosphor of the present invention represented by the formula [II] is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more, and further preferably 0.75 or more. Here, the internal quantum efficiency means the ratio of the number of photons emitted to the number of photons of excitation light absorbed by the phosphor. If the internal quantum efficiency is low, the light emission efficiency tends to decrease.

  Furthermore, the phosphor of the present invention represented by the formula [II] is preferably as its absorption efficiency is high. The value is usually 0.6 or more, preferably 0.7 or more, more preferably 0.75 or more, and still more preferably 0.8 or more. The external quantum efficiency is determined by the product of the internal quantum efficiency and the absorption efficiency. In order to have a high external quantum efficiency, it is preferable that the absorption efficiency is also high.

  In addition, the phosphor of the present invention represented by the formula [II] generally has the formula [II] for properties other than those described here, such as temperature characteristics, excitation wavelength, solubility, durability, and particle size. It is the same as the phosphor of the present invention represented by I].

(Characteristics of the phosphor of the present invention represented by the formula [II ′])
Among the phosphors of the present invention represented by the formula [II], in the case of a yellow phosphor represented by the following formula [II ′] and having an emission peak wavelength of 550 nm to 570 nm, the L ^* value is 100 or more and b ^*. It has a characteristic characteristic that the value is 77 or more.
M ³ _e (Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II ′]
(In the formula [II ′], M ³ represents an activating element, and e represents a positive number satisfying 0 <e ≦ 0.2.)

[2-2-3. Phosphor represented by formula [III]]
(Characteristics related to excitation spectrum)
The phosphor of the present invention represented by the formula [III] is preferably excitable with light in a wavelength range of 200 nm to 500 nm. In particular, in order to suitably use a semiconductor element or the like as a first light emitter and use the light as a phosphor excitation light source, for example, light in a blue region (wavelength range: 420 nm to 500 nm) and It is preferable that excitation is possible with light in the near ultraviolet region (wavelength range: 300 nm to 420 nm).

Furthermore, the phosphor of the present invention represented by the formula [III] is in the emission spectrum diagram when irradiated with light having a wavelength of 410 nm with respect to the emission peak intensity value in the emission spectrum diagram when irradiated with light having a wavelength of 390 nm. The ratio of the emission peak intensity value is usually 90% or more.
The emission spectrum can be measured in the same manner as described in the section of the phosphor of the present invention represented by the formula [I].

(Characteristics related to emission spectrum)
The phosphor of the present invention represented by the formula [III] has an emission peak wavelength λp (nm) of usually 610 nm or more, more preferably 620 nm or more when an emission spectrum is measured when excited with light having a wavelength of 455 nm. More preferably, it is 630 nm or more, and particularly preferably 650 nm or more. Accordingly, when this inorganic compound is used as a red phosphor of an image display device, an image display device having a high NTSC ratio can be obtained, which is preferable. Further, the upper limit of the emission peak wavelength is usually 680 nm or less.

  In addition, the phosphor of the present invention represented by the formula [III] has a FWHM of an emission peak in the above emission spectrum of usually 80 nm or more. Further, it is usually preferably in the range of less than 105 nm, especially 100 nm or less, and more preferably 95 nm or less. If this half-value width (FWHM) is too narrow, the color rendering property may be lowered when used as illumination because the luminance is reduced. If it is too wide, it is used for an image display device such as a liquid crystal display. Since the color purity is lowered, the color reproduction range of the image display device may be narrowed.

  In addition, the phosphor of the present invention represented by the formula [III] is measured for the emission spectrum, and its emission peak wavelength, as described in the section of the phosphor of the present invention represented by the formula [I]. The peak relative intensity and peak half width can be calculated.

(Luminescent color)
The emission color of the phosphor of the present invention represented by the formula [III] is, as a chromaticity coordinate value based on JIS Z8701, x is usually 0.5 or more, preferably 0.55 or more, more preferably 0.6 or more, More preferably, it is 0.65 or more, and is usually 0.75 or less. Moreover, y is usually 0.4 or less, preferably 0.35 or less, more preferably 0.3 or less, and usually 0.2 or more.

(Object color)
The phosphor of the present invention represented by the formula [III] is characterized in that the object color is clearer than the conventional phosphor having the same composition. Specifically, when the object color is expressed in the L ^* a ^* b ^* color system, it is preferable that either the a ^* value is 38 or more or the b ^* value is 42 or more.
The b ^* value indicates that a larger numerical value indicates a brighter color as red, and is usually 40 or more, preferably 42 or more, and more preferably 43 or more. On the other hand, the upper limit of the b ^* value is theoretically 200 or less, but is usually preferably 120 or less. This is because if the b ^* value is too large, the emission wavelength may shift to the longer wavelength side and the luminance may decrease.
The L ^* value indicates that the larger the value, the clearer the color, and usually 70 or more, preferably 75 or more, and more preferably 80 or more.
The a ^* value indicates that a larger numerical value indicates a clearer color as red, and is usually 30 or more, preferably 35 or more, more preferably 38 or more, and particularly preferably 40 or more. . In general, the value is 60 or less.

(Quantum efficiency)
The phosphor of the present invention represented by the formula [III] has an external quantum efficiency higher than that of a conventional phosphor having the same composition. Specifically, the external quantum efficiency is usually 0.62 or more. In order to design a light emitting device with high emission intensity, the higher the external quantum efficiency, the better.

  The internal quantum efficiency of the phosphor of the present invention represented by the formula [III] is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more, and further preferably 0. .75 or more. Here, the internal quantum efficiency means the ratio of the number of photons emitted to the number of photons of excitation light absorbed by the phosphor. If the internal quantum efficiency is low, the light emission efficiency tends to decrease.

  Furthermore, the phosphor of the present invention represented by the formula [III] is more preferable as its absorption efficiency is higher. The value is usually 0.6 or more, preferably 0.7 or more, more preferably 0.75 or more, and further preferably 0.8 or more. The external quantum efficiency is determined by the product of the internal quantum efficiency and the absorption efficiency. In order to have a high external quantum efficiency, it is preferable that the absorption efficiency is also high.

(Temperature characteristics)
Furthermore, the phosphor of the present invention represented by the formula [III] has excellent temperature characteristics. Specifically, the ratio of the emission peak intensity value in the emission spectrum diagram at 150 ° C. to the emission peak intensity value in the emission spectrum diagram at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 55% or more. And preferably 60% or more, particularly preferably 70% or more.
Further, since the emission intensity of ordinary phosphors decreases with increasing temperature, it is unlikely that the ratio exceeds 100%, but it may exceed 100% for some reason. However, if it exceeds 150%, the color shift tends to occur due to a temperature change.

  The phosphor of the present invention represented by the formula [III] is excellent not only in terms of the emission peak intensity but also in terms of luminance. Specifically, the ratio of the luminance at 150 ° C. to the luminance at 20 ° C. when irradiated with light having a wavelength of 455 nm is usually 55% or more, preferably 60% or more, particularly preferably 70% or more. is there.

  When measuring the temperature characteristics, it may be performed in the same manner as described in the section of the phosphor of the present invention represented by the formula [I].

(durability)
The phosphor of the present invention represented by the formula [III] is usually 1000 ° C. or higher, preferably 1200 ° C. or higher, more preferably 1500 ° C. or higher, particularly preferably 1700 ° C. in a durability test such as heating for 2 hours in a nitrogen atmosphere. Even if it is above, it does not decompose.

  Furthermore, the phosphor of the present invention represented by the formula [III] is usually 200 hours or longer, preferably 500 hours or longer, more preferably 600 hours in a durability test in an environment where the temperature is 85 ° C. and the relative humidity is 85%. As described above, it is particularly preferably stable for 800 hours or more. In this case, the longer the stable time, the better. However, 1000 hours is usually sufficient. Here, “stable” means that the ratio of the emission intensity after the durability test to the emission intensity before the durability test is 50% or more. The durability measurement may be performed in the same manner as described in the section of the phosphor of the present invention represented by the formula [I].

[2-2-4. Phosphor represented by formula [IV]]
(Characteristics related to excitation spectrum)
The phosphor of the present invention represented by the formula [IV] is preferably excitable with light in a wavelength range of 200 nm to 500 nm. In particular, in order to suitably use a semiconductor element or the like as a first light emitter and use the light as a phosphor excitation light source, for example, light in a blue region (wavelength range: 420 nm to 500 nm) and It is preferable that excitation is possible with light in the near ultraviolet region (wavelength range: 300 nm to 420 nm).

Furthermore, the phosphor of the present invention represented by the formula [IV] is a light emission spectrum when irradiated with light having a wavelength of 410 nm with respect to a light emission peak intensity value in a light emission spectrum when irradiated with light having a wavelength of 390 nm. The ratio of the light emission peak intensity value is usually 90% or more.
The emission spectrum can be measured in the same manner as described in the section of the phosphor of the present invention represented by the formula [I].

(Characteristics related to emission spectrum)
The phosphor of the present invention represented by the formula [IV] has an emission peak wavelength λp (nm) of 590 nm or more, preferably 600 nm or more, when measuring an emission spectrum when excited with light having a wavelength of 455 nm. Preferably it is 610 nm or more. The upper limit of the emission peak wavelength is usually 680 nm or less.

  In addition, the phosphor of the present invention represented by the formula [IV] has an emission peak FWHM in the above-described emission spectrum of usually 80 nm or more. In addition, it is usually less than 120 nm, preferably 110 nm or less, more preferably 100 nm or less. If this half-value width (FWHM) is too narrow, the color rendering property may be lowered when used as illumination because the luminance is reduced. If it is too wide, it is used for an image display device such as a liquid crystal display. Since the color purity is lowered, the color reproduction range of the image display device may be narrowed.

  The phosphor of the present invention represented by the formula [IV] is measured for the emission spectrum and its emission peak wavelength in the same manner as described in the section of the phosphor of the present invention represented by the formula [I]. The peak relative intensity and the peak half-value width can be calculated.

(Luminescent color)
As for the luminescent color of the phosphor of the present invention represented by the formula [IV], x is usually 0.50 or more, preferably 0.53 or more, and usually 0.75 or less as chromaticity coordinate values based on JIS Z8701. And y is usually 0.5 or less, preferably 0.45 or less, more preferably 0.43 or less, and usually 0.2 or more.

(Object color)
The phosphor of the present invention represented by the formula [IV] is characterized in that the object color is clearer than the conventional phosphor having the same composition. Specifically, when the object color is expressed in the L ^* a ^* b ^* color system and the object color is expressed in the L ^* a ^* b ^* color system, the b ^* value is 63 or more. It is preferable that there is, more preferably 65 or more. On the other hand, the upper limit of the b ^* value is theoretically 200 or less, but is usually preferably 120 or less. This is because if the b ^* value is too large, the emission wavelength may shift to the longer wavelength side and the luminance may decrease.
The L ^* value indicates that the larger the numerical value, the clearer the color, and usually 70 or more, preferably 80 or more, and more preferably 90 or more.
The a ^* value indicates that a larger numerical value indicates a clearer color as red, and is usually 15 or more, preferably 20 or more, more preferably 25 or more, and further preferably 30 or more. It is. In general, the value is 60 or less.

(Quantum efficiency)
The phosphor of the present invention represented by the formula [IV] has an external quantum efficiency higher than that of a conventional phosphor having the same composition. Specifically, the external quantum efficiency is usually 0.59 or more. In order to design a light emitting device with high emission intensity, the higher the external quantum efficiency, the better.

  The internal quantum efficiency of the phosphor of the present invention represented by the formula [IV] is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more. Here, the internal quantum efficiency means the ratio of the number of photons emitted to the number of photons of excitation light absorbed by the phosphor. If the internal quantum efficiency is low, the light emission efficiency tends to decrease.

  Furthermore, the phosphor of the present invention represented by the formula [IV] is more preferable as its absorption efficiency is higher. The value is usually 0.6 or more, preferably 0.7 or more, more preferably 0.75 or more, and still more preferably 0.8 or more. The external quantum efficiency is determined by the product of the internal quantum efficiency and the absorption efficiency. In order to have a high external quantum efficiency, it is preferable that the absorption efficiency is also high.

[2-2-5. Others]
(Weight median diameter)
The phosphor of the present invention has a weight median diameter D ₅₀ of usually 0.01 μm or more, preferably 1 μm or more, more preferably 5 μm or more, further preferably 10 μm or more, and usually 100 μm or less, preferably 30 μm or less. More preferably, it is in the range of 20 μm or less. When the weight-average median diameter D ₅₀ is too small, and the luminance decreases tends to phosphor particles aggregate. On the other hand, when the weight median diameter is too large, there is a tendency for coating unevenness and blockage of a dispenser to occur.

The particle size distribution QD value of the phosphor of the present invention is usually 0.5 or less, preferably 0.3 or less, particularly preferably 0.25 or less, and usually 0.1 or more.
When a plurality of phosphors having different weight median diameters D ₅₀ are mixed and used in order to increase the light emission efficiency and the light absorption efficiency, the QD of the mixed phosphor may be larger than 0.3.

The above-mentioned weight-average median diameter D _50, is a value obtained by the frequency particle size distribution curve. The frequency reference particle size distribution curve is obtained by measuring the particle size distribution by a laser diffraction / scattering method. Specifically, the phosphor was dispersed in an aqueous solution containing a dispersant, and measured by a laser diffraction particle size distribution measuring device (Horiba LA-300) in a particle size range of 0.1 μm to 600 μm. Is. In this frequency particle size distribution curve, the accumulated value is the particle size value when the 50% and weight-average median diameter D _50. Further, the particle size values when the integrated values are 25% and 75% are denoted as D ₂₅ and D ₇₅ , respectively. Standard deviation (4-minute deviation) QD = (D ₇₅ -D ₂₅ ) / (D ₇₅ + D ₂₅ ). A small QD means a narrow particle size distribution.

  Furthermore, the aspect ratio of the phosphor particles is obtained by observing the crystal particles with a scanning electron microscope (SEM) and dividing the length of the phosphor in the major axis direction by the length of the thickest portion in the direction perpendicular to the major axis. Can be obtained. In the phosphor of the present invention, when the SEM observation is performed on at least 50 crystal grains, the ratio of particles having an aspect ratio of 0.5 or more and 1 or less is usually 50% or more, preferably 80% or more. More preferably, it is 90% or more, more preferably 95% or more, and particularly preferably all particles fall within this range.

  Usually, the phosphor particles are often composed of secondary particles in which a plurality of primary particles are aggregated. The average particle size of the primary particles is usually 2 μm or more, preferably 5 μm or more. The thickness is preferably 10 μm or more, and usually 30 μm or less, preferably 20 μm or less, more preferably 15 μm or less.

  Furthermore, the electrical conductivity of the supernatant of the dispersion obtained by dispersing the phosphor of the present invention in 10 times the weight ratio of water and allowing it to stand for 1 hour is preferably as low as possible from the viewpoint of light emission characteristics. Considering the properties, it is usually 10 mS / m or less, preferably 5 mS / m or less, more preferably 4 mS / m or less. Further, the pH of the supernatant at that time is usually 4 or more, preferably 5 or more, more preferably 6 or more, and usually 10 or less, preferably 9 or less, more preferably 8 or less.

  In addition, as a method of measuring the electrical conductivity, the specific gravity is heavier than that of water by stirring and dispersing in water 10 times the weight of the phosphor for a predetermined time, for example, 10 minutes, and then allowing to stand for 1 hour. The particles are allowed to settle naturally, and the electrical conductivity of the supernatant liquid at this time may be measured using an electrical conductivity meter “EC METER CM-30G” manufactured by Toa Decay Co., Ltd. Although there is no restriction | limiting in particular as water used for a washing process and a measurement of electrical conductivity, Demineralized water or distilled water is preferable. Among them, those having particularly low electric conductivity are preferable, and those having a conductivity of usually 0.0064 mS / m or more, and usually 1 mS / m or less, preferably 0.5 mS / m or less are used. The electrical conductivity is usually measured at room temperature (about 25 ° C.).

[2-3. Method for producing phosphor]
The phosphor of the present invention is not particularly limited as long as the above silicon nitride is used as a raw material, and may be produced according to a known phosphor production method. For example, various raw materials (hereinafter, referred to as “phosphor raw material” as appropriate) such as a metal element constituting a target phosphor and a compound containing the metal element are mixed (mixing step), and the obtained mixture is fired. What is necessary is just to manufacture by doing (baking process). Further, for example, instead of the phosphor raw material or together with the phosphor raw material, a fired product obtained by mixing and firing the phosphor raw material may be fired and manufactured. Here, the phosphor raw material and the fired product thereof may be collectively referred to as “phosphor precursor” as appropriate.

(Phosphor raw material)
As a phosphor raw material used for manufacturing the phosphor of the present invention, any material can be used as long as at least the silicon nitride of the present invention is used as a part of the phosphor raw material. For example, the metal, alloy, imide compound, amide compound, oxynitride, nitride, oxide, hydroxide, carbonate, nitrate, sulfate, oxalate, carboxylate, halogen of each element constituting the phosphor And the like. From these phosphor raw materials, the reactivity to the composite oxynitride, the low generation amount of NOx, SOx, etc. during firing may be selected as appropriate.

For example, when the phosphor represented by the above formula [I] is produced, a raw material of the element M ¹ as an activation element (hereinafter referred to as “M ¹ source” as appropriate), a Ba raw material (hereinafter referred to as “Ba source as appropriate”). ), A raw material of the metal element M ² (hereinafter appropriately referred to as “M ² source”), and a raw material of L (hereinafter appropriately referred to as “L source”), respectively, include the following. .

Among the M ¹ sources, specific examples of Eu sources include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (C ₂ O ₄ ) ₃ · 10H ₂ O, EuCl ₂ , EuCl ₃ , EuF _2. EuF ₃ , Eu (NO ₃ ) ₃ .6H ₂ O, EuN, EuNH, Eu (NH ₂ ) _{2 and the} like. Of these, Eu ₂ O ₃ , EuCl _{2 and the} like are preferable, and Eu ₂ O ₃ is particularly preferable.

In addition, among M ¹ sources, raw materials of Mn, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm, and Yb (hereinafter referred to as “Mn source”, “Ce source”, “Pr source, respectively, as appropriate”) ”,“ Nd source ”,“ Sm source ”,“ Tb source ”,“ Dy source ”,“ Ho source ”,“ Er source ”,“ Tm source ”, and“ Yb source ”) As specific examples of the raw material of the agent element, in each compound given as a specific example of the Eu source, Eu is activated by Mn, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm, Yb, etc. Examples include compounds replaced with elements.

Specific examples of the Ba source include BaO, Ba (OH) ₂ .8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (C ₂ O ₄ ), Ba (OCOCH ₃ ) ₂ , BaCl. ₂ , BaF ₂ , Ba ₂ N, BaNH, Ba (NH ₂ ) _{2 and the} like. Of these, carbonates, oxides, and the like can be preferably used, but carbonates are more preferable from the viewpoint of handling because oxides easily react with moisture in the air. Of these, BaCO ₃ is preferable. This is because the stability in the air is good, and it is easily decomposed by heating, so that undesired elements hardly remain and it is easy to obtain high-purity raw materials. When carbonate is used as a raw material, it is preferable to pre-calcinate the carbonate and use it as a raw material.

Among the M ² sources, specific examples of Sr raw materials (Sr sources) include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (C ₂ O). ₄ ) · H ₂ O, Sr (OCOCH ₃ ) ₂ · 0.5H ₂ O, SrCl ₂ , SrF ₂ , Sr ₂ N, SrNH, Sr (NH ₂ ) _{2 and the} like. Among these, SrCO ₃ is preferable. This is because the stability in the air is good, it is easily decomposed by heating, it is difficult for undesired elements to remain, and it is easy to obtain high-purity raw materials.

Among the M ² sources, specific examples of Mg raw materials (Mg sources) include MgO, Mg (OH) ₂ , basic magnesium carbonate (mMgCO ₃ .Mg (OH) ₂ .nH ₂ O), Mg (NO ₃ ) ₂ · 6H ₂ O, MgSO ₄ , Mg (C ₂ O ₄ ) · 2H ₂ O, Mg (OCOCH ₃ ) ₂ · 4H ₂ O, MgCl ₂ , MgF ₂ , Mg ₃ N ₂ , MgNH, Mg (NH ₂ ) ₂ etc. are mentioned. Of these, MgO and basic magnesium carbonate are preferred.

Among the M ² sources, specific examples of the Ca raw material (Ca source) include CaO, Ca (OH) ₂ , CaCO ₃ , Ca (NO ₃ ) ₂ .4H ₂ O, CaSO ₄ .2H ₂ O, and Ca. _{(C 2 O 4) · H} 2 O, Ca (OCOCH 3) 2 · H 2 O, CaCl 2, CaF 2, Ca 3 N 2, CaNH, Ca (NH 2) 2 and the like. Of these, CaCO ₃ , anhydrous CaCl _{2 and the} like are preferable.

Among the M ² sources, specific examples of the Zn raw material (Zn source) include zinc such as ZnO, ZnF ₂ , ZnCl ₂ , Zn (OH) ₂ , Zn ₃ N ₂ , ZnNH, and Zn (NH ₂ ) _2. And a compound (however, it may be a hydrate). Of these, ZnF ₂ .4H ₂ O (however, it may be an anhydride) is preferable from the viewpoint that the effect of promoting particle growth is high.
Further, when carbonate is used as the M ² source, it is preferable to use the carbonate as a raw material after calcining the carbonate in advance.

Among the L sources, the silicon nitride of the present invention is used as a Si raw material (Si source). However, raw materials other than the silicon nitride of the present invention may be used as long as the effects of the present invention are not significantly impaired. Examples of raw materials other than silicon nitride of the present invention include SiO ₂ . It is also possible to use a compound as a SiO _2. Specific examples of such a compound include SiO ₂ , H ₄ SiO ₄ , Si (OCOCH ₃ ) _{4 and the} like.
Furthermore, other Si ₃ N ₄ can be used as a raw material other than the silicon nitride of the present invention. However, even in this case, the other Si ₃ N ₄ is preferably Si ₃ N ₄ having a small particle size and high purity in terms of light emission efficiency from the viewpoint of reactivity. Furthermore, from the viewpoint of luminous efficiency, β-Si ₃ N ₄ is preferable to α-Si ₃ N ₄ , and Si ₃ N ₄ is preferably a material having a high reflectance. Of these, those having a small content of carbon elements as impurities are particularly preferred. The smaller the carbon content, the better. However, usually 0.001% by weight or more is contained, and in reality, 0.01% by weight or more is often contained, and usually 0.3% by weight or less. Preferably it is 0.2 weight% or less, More preferably, it is 0.1 weight% or less, More preferably, it is 0.05 weight% or less, Most preferably, it is 0.03 weight% or less.
On the other hand, from the viewpoint of increasing the particle size of the phosphor particles, it is preferable that the particle size of the raw material Si ₃ N ₄ is large.

Among the L sources, for example, GeO ₂ or Ge ₃ N ₄ is preferably used as the Ge source. A compound that becomes GeO ₂ can also be used. Specific examples of such a compound include GeO ₂ , Ge (OH) ₄ , Ge (OCOCH ₃ ) ₄ , and GeCl ₄ .
Specific examples of other L sources include compounds in which Si or Ge is replaced by Ti, Zr, Hf, or the like in the respective compounds listed as specific examples of the Si source or Ge source.

Incidentally, M ¹ source described above, Ba source, M ² source and L sources, respectively, may be used singly or in combination of two or more kinds in any combination and in any ratio.

For example, when the phosphor represented by the above formula [II] is produced, as a specific example of the raw material of the element M ³ as an activator (hereinafter referred to as “M ³ source” as appropriate), the above M The thing similar to ¹ source is mentioned. Specific examples of the Ca source, the Sr source, the Ba source, and the Si source are the same as those described in the description of the phosphor material of the phosphor represented by the above formula [I].
Incidentally, M ³ source as described above, Ca source, Sr source, Ba source and Si source, respectively, may be used singly or in combination of two or more kinds in any combination and in any ratio.

For example, in the case of manufacturing the phosphor represented by the above formula [III], a raw material of the element M ⁴ as an activator (hereinafter referred to as “M ⁴ source” as appropriate), a raw material of M ⁵ (hereinafter referred to as appropriate). called "M ⁵ source".), Al raw material (hereinafter appropriately referred to as "Al source".) and the Si source include those each as follows.

Among the M ⁴ sources, specific examples of the Eu source include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (C ₂ O ₄ ) ₃ .10H ₂ O, EuF ₃ , EuCl ₂ and EuCl _{3. , Eu (NO 3) 3 ·} 6H 2 O, EuN, EuNH, Eu (NH 2) 2 and the like. Among these, an oxide or a halide is preferable, a halide is more preferable, and EuF ₃ is particularly preferable.

Also, among the ^{M 4} source, Mn, Ce, Pr, Nd , Sm, Tb, Dy, Ho, Er, as other specific examples of the material of the activator elements such as Tm, and Yb is particularly the Eu source In each of the compounds mentioned as examples, compounds in which Eu is replaced with Mn, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, Tm and Yb, respectively, can be mentioned.

Among the M ⁵ sources, specific examples of the Ba source include BaO, Ba (OH) ₂ .8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (C ₂ O ₄ ), Ba ( OCOCH ₃ ) ₂ , BaF ₂ , BaCl ₂ , Ba ₃ N ₂ , Ba ₂ N, BaNH, Ba (NH ₂ ) _{2 and the} like. Of these, Ba ₃ N ₂ is preferred.

Among the M ⁵ sources, specific examples of the Sr source include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (C ₂ O ₄ ) · H _2. O, Sr (OCOCH ₃ ) ₂ .0.5H ₂ O, SrF ₂ , SrCl ₂ , Sr ₃ N ₂ , Sr ₂ N, SrNH, Sr (NH ₂ ) _{2 and the} like can be mentioned. Among these, Sr ₃ N ₂ is preferable.

Among the M ⁵ sources, specific examples of the Mg source include MgO, Mg (OH) ₂ , basic magnesium carbonate (mMgCO ₃ .Mg (OH) ₂ .nH ₂ O), Mg (NO ₃ ) ₂ .6H. _{2 O, MgSO 4, Mg (} C 2 O 4) · 2H 2 O, Mg (OCOCH 3) 2 · 4H 2 O, MgF 2, MgCl 2, Mg 3 N 2, MgNH and the like. Among these, Mg ₃ N ₂ is preferable.

Among the above M ⁵ sources, specific examples of the Ca source include CaO, Ca (OH) ₂ , CaCO ₃ , Ca (NO ₃ ) ₂ .4H ₂ O, CaSO ₄ .2H ₂ O, Ca (C ₂ O _{4 ) · H 2 O, Ca (} OCOCH 3) 2 · H 2 O, CaF 2, CaCl 2, Ca 3 N 2, CaNH, Ca (NH 2) 2 and the like. Among these, Ca ₃ N ₂ is preferable.

AlN is preferably used as the Al source.
Examples of the Si source include the same materials as those described in the explanation of the phosphor material of the phosphor represented by the above formula [I].
In addition, each of the above-described M ⁴ source, M ⁵ source, Al source, and Si source may be used alone or in combination of two or more in any combination and ratio.

For example, in the case of producing a phosphor represented by the above formula [IV], as a specific example of a raw material of the element M ⁶ that is an activating element (hereinafter referred to as “M ⁶ source” as appropriate), the above M The thing similar to ¹ source is mentioned. Further, specific examples of the Mg source, the Ca source, the Sr source, the Ba source, and the Si source are the same as those described in the explanation of the phosphor material of the phosphor represented by the above formula [III]. Can be mentioned.
Incidentally, the above-mentioned M ⁶ source, Ca source, Sr source, Ba source, Zn source and Si source, respectively, may be used singly or in combination of two or more kinds in any combination and in any ratio.

Further, the impurities contained in the phosphor material are not particularly limited as long as the performance of the phosphor is not affected. However, with respect to Fe, Co, Cr and Ni, those usually used are 1000 ppm or less, preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 10 ppm or less, and particularly preferably 1 ppm or less.
The weight median diameter of each phosphor material is usually 0.1 μm or more, preferably 0.5 μm or more, and usually 30 μm or less, preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 3 μm or less. Is used. For this reason, depending on the type of the phosphor material, pulverization may be performed in advance by a dry pulverizer such as a jet mill. As a result, each phosphor raw material can be uniformly dispersed in the raw material mixture, and the solid phase reactivity of the raw material mixture can be increased by increasing the surface area of the phosphor raw material, thereby suppressing the generation of impurity phases. It becomes. In particular, in the case of a nitride material, it is preferable to use a material having a smaller particle size than other phosphor materials from the viewpoint of reactivity.

  Here, the O element and the N element in each phosphor composition are usually supplied as the anion component of the raw material of each constituent element or as a component contained in the firing atmosphere when the phosphor is manufactured.

  Moreover, in the said various phosphor raw materials, since the luminous efficiency of the fluorescent substance obtained by using the phosphor raw material with high purity and higher whiteness is improved, it is preferable. Specifically, the reflectance of the phosphor material in the wavelength range of 380 nm to 780 nm is preferably 60% or more, more preferably 70% or more, and further preferably 80% or more. In particular, at a wavelength in the vicinity of the emission peak wavelength of the phosphor of the present invention, the reflectance of the phosphor material is preferably 60% or more, more preferably 70% or more, still more preferably 80% or more, particularly Preferably it is 90% or more.

  The phosphor material may be used after being coprecipitated as a coprecipitation material. This coprecipitation raw material is a material in which part or all of the phosphor constituent elements are mixed at the atomic level. Usually, coprecipitation is performed by combining phosphor materials containing different phosphor constituent elements, so that the obtained coprecipitation raw material contains two or more phosphor constituent elements. By using the phosphor material after it is co-precipitated, a phosphor in which the phosphor constituent elements are uniformly mixed can be obtained, so that a phosphor having excellent emission intensity can be obtained. In particular, by using a coprecipitation raw material containing a luminescent center element (usually an activating element), the luminescent center element can be uniformly dispersed in the phosphor. Obtainable.

(Mixing process)
The phosphor of the present invention is obtained by weighing the phosphor materials so that the target composition is obtained, mixing them, and firing. In this case, it is preferable that the mixing is sufficiently performed using a ball mill or the like.

The phosphor raw material is preferably weighed so that the charged composition of the phosphor constituent elements in the mixture is the same as the composition of the target phosphor. At this time, an error in the weighing of each phosphor material is allowed to some extent, but in order to obtain a crystal with few lattice defects and impurity phases, the weighing error is preferably small. Specifically, the molar ratio of the M ¹ element, the M ² element, and the L element in the raw material mixture is within a range of ± 10% with respect to the molar ratio in the target phosphor composition (more specifically, Is usually 90% or more, preferably 95% or more, and usually 110% or less, preferably 105% or less.

In the case of producing a phosphor containing at least Eu and Pr as the M ¹ element in the composition of the formula [I], the Pr element is usually 5% in a molar ratio with respect to the total amount of the Ba element and the M ² element. In the following, it is preferable to use a material containing 4 mol% or less, more preferably 3 mol% or less, and firing it. Thereby, the fluorescent substance excellent in durability can be obtained more reliably. In addition, although there is no restriction | limiting in a minimum, Usually, it is 0.01 mol% or more.

  The mixing method is not particularly limited, and specifically, publicly known methods such as the following methods (A) and (B) can be arbitrarily used. As for these various conditions, for example, known conditions such as mixing and using two kinds of balls having different particle diameters in a ball mill can be appropriately selected.

  (A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., or pulverization using mortar and pestle, and mixer such as ribbon blender, V-type blender, Henschel mixer, or mortar and pestle And a dry mixing method in which the above phosphor raw materials are pulverized and mixed.

  (B) A solvent or a dispersion medium such as water or an alcohol solvent such as ethanol is added to the phosphor raw material described above, and mixed using, for example, a pulverizer, a mortar and pestle, or an evaporating dish and a stirring bar, A wet mixing method in which the slurry is dried and then dried by spray drying, heat drying, or natural drying.

  Further, when mixing and pulverizing, the phosphor material may be sieved as necessary. In this case, various commercially available sieves can be used, but it is preferable to use a resin such as a nylon mesh rather than a metal mesh such as a metal mesh in terms of preventing impurities from being mixed.

The mixing of the phosphor raw materials may be arbitrarily selected from the above-mentioned wet type and dry type according to the physical properties of the phosphor raw materials. For example, when using a nitride raw material, it is preferable to fill with an inert gas such as argon gas or nitrogen gas and mix with a glove box in which moisture is controlled so that the nitride raw material does not deteriorate due to moisture.
When mixing, the moisture in the atmosphere is preferably 10,000 ppm or less, more preferably 1000 ppm or less, still more preferably 10 ppm or less, and particularly preferably 1 ppm or less. Further, oxygen is preferably 1% or less, more preferably 1000 ppm or less, still more preferably 100 ppm or less, and particularly preferably 10 ppm or less.

(Baking process)
A phosphor is obtained by firing the obtained mixture. This firing is preferably performed by filling the phosphor material in a container such as a crucible and firing at a predetermined temperature and atmosphere.
As the container, it is preferable to use a heat-resistant container such as a crucible or a tray made of a material having low reactivity with each phosphor raw material. Examples of the material of the heat-resistant container used at the time of firing include ceramics such as alumina, quartz, boron nitride, silicon nitride, silicon carbide, magnesium, mullite, platinum, molybdenum, tungsten, tantalum, niobium, iridium, rhodium, and the like. Examples thereof include metals, alloys containing them as main components, and carbon (graphite). Here, the heat-resistant container made of quartz can be used for heat treatment at a relatively low temperature, that is, 1200 ° C. or less, and a preferable use temperature range is 1000 ° C. or less.
Examples of such heat-resistant containers are preferably boron nitride, alumina, silicon nitride, silicon carbide, platinum, molybdenum, tungsten, and tantalum heat-resistant containers, more preferably boron nitride. , Alumina, and molybdenum. Among these, alumina firing that is stable in the firing temperature range is preferred for firing in a reducing atmosphere such as in a nitrogen-hydrogen mixed gas. However, since it may react with alumina depending on the type of the phosphor material, in that case, it is preferable to use a heat-resistant container made of BN or molybdenum.

  The filling rate when filling the phosphor material into the heat-resistant container (hereinafter referred to as “heat-resistant container filling rate”) varies depending on the firing conditions, but the fired product is pulverized in a post-treatment step described later. It may be filled to such an extent that it does not become difficult to perform, and is usually 10% by volume or more and usually 90% by volume or less. Further, since the phosphor material filled in the crucible has a void ratio between the particles of the phosphor material, the volume of the phosphor material per 100 ml volume filled with the phosphor material is usually 10 ml or more, Preferably it is 15 ml or more, More preferably, it is 20 ml or more, Usually, 50 ml or less, More preferably, it is 40 ml or less, More preferably, it is 30 ml or less.

Further, when it is desired to increase the amount of the phosphor raw material to be processed at a time, it is preferable that heat is uniformly circulated in the heat-resistant container, for example, by decreasing the rate of temperature rise.
Moreover, it is preferable that the filling rate (hereinafter referred to as “furnace filling rate” as appropriate) when filling the heat-resistant container in the furnace is such that heat does not become uneven between the heat-resistant containers in the furnace.
Furthermore, in the above baking, when the number of heat-resistant containers in the baking furnace is large, for example, to make the heat transfer to each heat-resistant container uniform, such as slowing the temperature increase rate, It is preferable for firing without unevenness.

  Here, when a metal carbonate is used as the phosphor raw material, it is preferable to perform preliminary firing so that at least a part is converted to metal oxide so that the firing furnace is not damaged by the desorbed carbon dioxide. .

In the temperature raising process at the time of firing, it is preferable that a part of the temperature is reduced. Specifically, at any time when the temperature is preferably room temperature or higher, preferably 1500 ° C. or lower, more preferably 1200 ° C. or lower, and still more preferably 1000 ° C. or lower, a reduced pressure state (specifically Is preferably 10 ⁻² Pa or more and less than 0.1 MPa). Among them, it is preferable to introduce an inert gas or a reducing gas, which will be described later, into the system after reducing the pressure in the system and raise the temperature in that state.

  At this time, if necessary, the target temperature may be maintained for 1 minute or longer, preferably 5 minutes or longer, more preferably 10 minutes or longer. The holding time is usually 5 hours or less, preferably 3 hours or less, more preferably 1 hour or less.

The firing temperature is preferably set appropriately according to a known method because the optimum temperature differs depending on the target phosphor. For example, when the temperature is such that the fired powder is sintered, the light emission intensity may be low.
Specifically, when the phosphor of the present invention represented by the above formula [I] is produced, the calcination powder usually sinters at a calcination temperature exceeding 1600 ° C., and the luminescence intensity may be lowered. A powder having good crystallinity can be obtained at a firing temperature of around 0 ° C. Accordingly, the firing temperature for producing the phosphor of the present invention represented by the formula [I] is usually 1000 ° C. or higher, preferably 1100 ° C. or higher, more preferably 1150 ° C. or higher, and further preferably 1200 ° C. or higher. The temperature is usually 1600 ° C. or lower, preferably 1500 ° C. or lower, more preferably 1450 ° C. or lower.

  When the phosphor of the present invention represented by the above formula [II] is produced, a powder having good crystallinity is obtained at a firing temperature of around 1500 ° C. Therefore, the firing temperature for producing the phosphor of the present invention represented by the formula [II] is usually 1100 ° C. or higher, preferably 1200 ° C. or higher, more preferably 1300 ° C. or higher, and usually 1700 ° C. The temperature is not higher than ° C., preferably not higher than 1600 ° C., more preferably not higher than 1550 ° C.

  When producing the phosphor of the present invention represented by the above formula [III] or formula [IV], the baked powder usually sinters at a firing temperature exceeding 2000 ° C., and the emission intensity may be lowered. A powder having good crystallinity can be obtained at a firing temperature of about 1700 to 1800 ° C. Therefore, the firing temperature for producing the phosphor of the present invention represented by the formula [III] or [IV] is usually 1000 ° C. or higher, preferably 1300 ° C. or higher, more preferably 1500 ° C. or higher. Moreover, it is 1900 degrees C or less normally, Preferably it is 1850 degrees C or less, More preferably, it is 1800 degrees C or less.

  Although it does not restrict | limit especially as a baking atmosphere, Usually, it carries out in inert gas atmosphere or reducing atmosphere. Here, as described above, the valence of the activating element is preferably a divalent one, so that a reducing atmosphere is preferable. In addition, only 1 type may be used for an inert gas and reducing gas, and 2 or more types may be used together by arbitrary combinations and a ratio.

Examples of the inert gas and the reducing gas include carbon monoxide, hydrogen, nitrogen, argon, methane, and ammonia. Of these, a nitrogen gas atmosphere is preferable, and a hydrogen gas-containing nitrogen gas atmosphere is more preferable. As the nitrogen (N ₂ ) gas, it is preferable to use a purity of 99.9% or more. When using hydrogen-containing nitrogen, it is preferable to reduce the oxygen concentration in the electric furnace to 20 ppm or less. Further, the hydrogen content in the atmosphere is preferably 1% by volume or more, more preferably 2% by volume or more, and 100% by volume or less of hydrogen gas may be used, but 10% by volume or less is preferable, and 5% by volume. The following is more preferable. This is because if the hydrogen content in the atmosphere is too high, the safety may decrease, and if it is too low, a sufficient reducing atmosphere may not be achieved.

The inert gas and the reducing gas may be introduced before the start of temperature increase, but may be introduced during the temperature increase, or may be introduced when the firing temperature is reached. Or it is preferable to introduce in the middle of temperature rising.
Moreover, when calcination is performed under the flow of these inert gas and reducing gas, the calcination is usually performed at a flow rate of 0.1 to 10 liters / minute.

  The firing time is usually 0.5 hours or longer, preferably 1 hour or longer, although it varies depending on the temperature and pressure during firing. The firing time is preferably longer, but is usually 100 hours or shorter, preferably 50 hours or shorter, more preferably 24 hours or shorter, and further preferably 12 hours or shorter.

The pressure during firing is not particularly limited differs depending firing temperature, etc., usually 1 × ¹⁰ -5 Pa or more, preferably 1 × ¹⁰ -3 Pa or more, more preferably 0.01MPa or more, more preferably 0. The upper limit is usually 5 GPa or less, preferably 1 GPa or less, more preferably 200 MPa or less, and still more preferably 100 MPa or less. Among these, the atmospheric pressure to about 1 MPa is industrially preferable in terms of cost and labor.

  In the firing step, for example, a phosphor precursor other than the raw material mixture, such as a fired product obtained by mixing and firing part or all of the phosphor raw materials, is combined with the raw material mixture, or they are replaced with the raw material mixture. Alternatively, it may be fired.

(flux)
In the firing step, a flux may coexist in the reaction system from the viewpoint of growing good crystals. The type of flux is not particularly limited, _{examples, NH 4 Cl, NH 4 F} · HF , such as ammonium _halide; NaCO 3, alkali metal carbonates such as _{LiCO 3; LiCl, NaCl, KCl} , CsCl, LiF, NaF, KF, CsF, LiI, NaI, KI, alkali metal halides such as _{CsI; CaCl 2, BaCl 2,} SrCl 2, CaF 2, BaF 2, SrF 2, CaI 2, BaI 2, SrI alkaline earth such as ₂ Metal halides; alkaline earth metal oxides such as CaO, SrO, BaO; boron oxides such as B ₂ O ₃ , H ₃ BO ₃ , Na ₂ B ₄ O ₇ , K ₂ B ₄ O ₇ , boric acid And alkali metal or alkaline earth metal borate compounds; Li ₃ PO ₄ , NH ₄ H ₂ PO ₄ , BaHPO ₄ , Z Phosphate compounds such as n ₃ (PO ₄ ) ₂ ; Aluminum halides such as AlF ₃ ; Zinc halides such as ZnCl ₂ , ZnBr ₂ , ZnF ₂ , zinc oxide, zinc sulfide, zinc borate, zinc phosphate, etc. Zinc compounds; periodic table group 15 element compounds such as Bi ₂ O ₃ ; alkali metals such as Li ₃ N, Ca ₃ N ₂ , Sr ₃ N ₂ , Ba ₃ N ₂ , Sr ₂ N, Ba ₂ N, BN, Examples thereof include alkaline earth metals and nitrides of Group 13 elements. Among these, preferred are halides, and among these, alkali metal halides, alkaline earth metal halides, phosphate compounds, or Zn halides are preferred. Of these halides, fluorides and chlorides are preferred. Of these, more preferred are alkaline earth metals or Zn fluoride, and alkaline earth metal phosphates.

  The amount of flux used varies depending on the type of phosphor material, the material of the flux, etc., but is usually 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 1% by weight or more for each flux. In addition, it is usually 20% by weight or less, preferably 10% by weight or less. If the amount of flux used is too small, the effect of the flux may not appear. If the amount of flux used is too large, the flux effect will be saturated, or it will be incorporated into the host crystal and change the emission color, or the brightness will be reduced. It may cause Therefore, as the type of flux to be used, a compound containing the same element as the metal element constituting the host crystal is preferable.

In addition, a flux may use only 1 type and may use 2 or more types together by arbitrary combinations and a ratio. When two or more types are used in combination, the amount of flux used is generally 40% by weight or less, preferably 30% by weight or less, and more preferably 25% by weight or less. The total amount is usually 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 1% by weight or more.
Of the above-mentioned fluxes, those having deliquescence are preferably used, and when the phosphor is produced by multi-stage firing, it is preferred to use the flux at the later stage firing.
The phosphor of the present invention obtained by firing in the presence of a flux has an improved balance between quantum efficiency and particle size. Specifically, the primary particle size becomes large and the Q. D. Has a tendency to become narrower.

(Primary firing and secondary firing)
The firing step may be divided into primary firing and secondary firing, and the raw material mixture obtained by the mixing step may be first fired first, and then pulverized again with a ball mill or the like, followed by secondary firing. That is, in order to further advance the solid phase reaction in the firing step and improve the crystallinity, the firing step may be performed in multiple stages instead of one stage. For example, the raw material mixture obtained by the mixing step is first fired first (first firing step), then pulverized again with a ball mill or the like as necessary, and then fired again (second firing step). Do it at least once. The re-baking (second baking step) may be performed as many times as secondary baking or tertiary baking. At this time, the primary fired fired product may be introduced into the subsequent firing only with the fired product, or a part of the aforementioned phosphor raw material mixed and fired is pulverized and the remaining raw materials are mixed there And it can also take the aspect of baking.

The temperature of the primary firing is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 800 ° C. or higher, preferably 1000 ° C. or higher, and usually 1600 ° C. or lower, preferably 1400 ° C. or lower, more preferably 1300 ° C. or lower. Range.
Here, in order to obtain a phosphor having a uniform particle size, it is preferable to advance the solid phase reaction in a powder state by setting the primary firing temperature low. On the other hand, in order to obtain a high-luminance phosphor, it is preferable that the primary firing temperature is set high and the raw materials are sufficiently mixed and reacted in a molten state and then grown by secondary firing.
The time for the primary firing is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 1 hour or longer, preferably 2 hours or longer, and usually 100 hours or shorter, preferably 50 hours or shorter, more preferably 24 hours or shorter. More preferably, it is 12 hours or less.

The conditions such as the temperature and time of the secondary firing are basically the same as the conditions described in the above-mentioned firing step column.
The flux may be mixed before the primary firing or may be mixed before firing after the secondary firing. Also, the firing conditions such as the atmosphere may be changed after the primary firing and the secondary firing.
The firing conditions at this time are appropriately selected within the same range as described above. However, among the firing temperatures in the two consecutive firing steps, the one having at least one step of setting the latter firing temperature to a higher temperature promotes the crystal growth of the phosphor and improves the crystallinity. This is preferable because it can be increased.

  In the above multi-stage firing, the fired product obtained in the firing step (first firing step) is washed at least once (cleaning step), and then fired again (second firing). It is preferable to use for (process). By performing the washing step, the impurity phase and the like attached to the fired product can be removed, so that the afterglow time of the phosphor and the amount of the impurity phase can be reduced. In particular, it is effective to carry out after the first firing step and / or before the final firing step.

  The washing can be performed, for example, with water such as deionized water, an organic solvent such as ethanol, or an alkaline aqueous solution such as ammonia water. Further, for the purpose of removing the impurity phase adhering to the surface of the fired product such as flux and improving the light emission characteristics, for example, an inorganic acid such as hydrochloric acid, nitric acid, sulfuric acid; or an aqueous solution of an organic acid such as acetic acid is used. It can also be used. In this case, it is preferable to further wash with water after washing in an acidic aqueous solution.

As the degree of washing, it is preferable that the pH of the supernatant obtained by dispersing the washed product after washing in water 10 times by weight and allowing to stand for 1 hour is neutral (about pH 5-9). This is because if it is biased to basic or acidic, the liquid medium or the like may be affected when mixed with the liquid medium or the like described later.
The degree of washing can also be expressed by the electrical conductivity of a supernatant obtained by dispersing the fired product after washing in 10 times the weight ratio of water and allowing it to stand for 1 hour. The electrical conductivity is preferably as low as possible from the viewpoint of light emission characteristics, but in consideration of productivity, the washing treatment is repeated until it is usually 10 mS / m or less, preferably 5 mS / m or less, more preferably 4 mS / m or less. It is preferable.

  As a method for measuring the electrical conductivity, calcined particles having a specific gravity heavier than water are obtained by stirring and dispersing in water 10 times the weight of the calcined product for a predetermined time, for example, 10 minutes, and then allowing to stand for 1 hour. The electrical conductivity of the supernatant liquid at this time may be measured using an electrical conductivity meter “EC METER CM-30G” manufactured by Toa Decay Co., Ltd. Although there is no restriction | limiting in particular as water used for a washing process and a measurement of electrical conductivity, Demineralized water or distilled water is preferable. Among them, those having particularly low electric conductivity are preferable, and those having a conductivity of usually 0.0064 mS / m or more, and usually 1 mS / m or less, preferably 0.5 mS / m or less are used. The electrical conductivity is usually measured at room temperature (about 25 ° C.).

  In addition, the pulverization step is performed to pulverize the fired product when the fired product is excessive. The pulverization method is not particularly limited, and for example, the dry pulverization method and the wet pulverization method described in the description of the mixing process of the phosphor raw material can be used.

In addition, when performing multi-stage baking, the flux may be mixed in any baking process, but it is particularly effective to use it in the first baking process and / or the final baking process. Moreover, you may change baking conditions, such as atmosphere, for every baking process.
In the above firing, if the number of crucibles in the firing furnace is large, for example, the heat transfer rate to each crucible can be made uniform by, for example, slowing the temperature increase rate, and firing is performed evenly. It is preferable for this purpose.

・ Preferable operation when using nitride as the phosphor material When using nitride as the phosphor material, in order to increase the solid-phase reactivity of the material mixture and suppress the formation of impurity phases, the nitride is uniformly in the material mixture. It is preferable to mix and disperse. As a specific method for realizing this, for example, a phosphor material other than nitride may be mixed in advance, fired, and pulverized, and nitride may be mixed and fired. In addition, when the nitride material is previously pulverized with a dry pulverizer such as a jet mill as a phosphor raw material, the surface area of the silicon nitride powder is increased, and the solid phase reactivity of the nitride is also increased. This is particularly suitable because it contributes to the improvement of. In addition, although these illustrated methods may be performed alone, they are preferably performed in combination.

(Formation of solid solution)
Furthermore, when the phosphor of the present invention represented by the formula [I ′] is produced by forming a solid solution of the phosphor of the present invention represented by the formula [I] and the langasite, first, the formula [I ′] The phosphor and langasite represented by I] may be independently obtained according to or in accordance with the above-described production method, and then mixed and fired to form a solid solution. Moreover, the solid solution may be fired by mixing the raw material powder containing the elements constituting the solid solution from the beginning in accordance with the intended composition of the formula [I ′] and firing it.

(Post-processing)
After the heat treatment in the above-described firing step, a reheating (annealing) step, pulverization, washing, drying, classification treatment, and the like are performed as necessary.

-Reheating process A reheating process is a process which heat-processes with respect to the fluorescent substance obtained at the baking process at the temperature lower than a baking temperature. In order to improve the durability of the phosphor, it is preferable to have this step.
As the heat treatment temperature in the reheating step, for example, in the case of the phosphor represented by the formula [I], although it depends on the atmosphere during the heat treatment, it is usually lower than 1150 ° C., preferably 1050 ° C. or less, more preferably Is 1000 ° C. or lower, more preferably 900 ° C. or lower, particularly preferably 800 ° C. or lower, and usually 300 ° C. or higher, preferably 400 ° C. or higher, more preferably 500 ° C. or higher, more preferably 600 ° C. or higher, particularly preferably 700 ° C. It is above ℃.

As an atmosphere at the time of the heat treatment in the reheating process, in addition to the same atmosphere as described in the section of the firing process, an oxygen-containing inert gas such as air or oxygen-containing nitrogen can also be used.
In the case of using such an oxygen-containing gas, the oxygen concentration is usually preferably 1% or less.

The pressure at the time of the heat treatment in the reheating step may be the same as that described in the firing step.
Here, when it is necessary to desorb hydrogen taken into the phosphor crystal at the time of firing, it is preferable to use a reduced pressure condition.
At this time, when the phosphor is heated to 1000 ° C. in a vacuum, the H ₂ gas emission amount measured using a temperature-programmed desorption gas analyzer is usually 1 cm ³ / g or less with respect to the phosphor, preferably 0.2 cm ³ / g or less, more preferably 0. By appropriately adjusting the reheating atmosphere, pressure and time so as to be 1 cm ³ / g or less, a phosphor having high luminance and high durability can be obtained.
The heat treatment time in the reheating step is usually 0.1 hour or longer, preferably 0.5 hour or longer. From the viewpoint of productivity, it is usually 100 hours or shorter, preferably 50 hours or shorter, more preferably 24 hours. Hereinafter, it is more preferably 12 hours or less.

By having this reheating process, distortion and defects in the phosphor crystal can be further reduced, the crystallinity of the phosphor can be improved, and modification of the phosphor surface can be expected, improving the durability of the phosphor. It is thought that it contributes to.
In particular, when producing an oxynitride phosphor selected from the group consisting of, for example, nitridosilicate, nitridoaluminosilicate, oxonitridosilicate, oxonitridoaluminosilicate and carbonitridealuminosilicate, it is more than the firing temperature. It is preferable to perform the reheating step of performing the heat treatment at a low temperature because the effect is remarkably exhibited.

Note that the reheating step may be performed on the phosphor after the firing step, or may be performed on the phosphor after performing the below-described pulverization, washing, classification steps, and the like.
Further, the heat treatment may be performed a plurality of times by changing the atmosphere. Among these, it is preferable to perform the reheating treatment in an H ₂ containing atmosphere after the reheating treatment in an oxygen containing atmosphere.

-Grinding treatment The grinding treatment is preferably performed on the fired product when, for example, the obtained phosphor does not have a desired particle size. The pulverization method is not particularly limited, and for example, the dry pulverization method and the wet pulverization method described in the description of the raw material mixing step can be used. In particular, in order to suppress the destruction of the generated phosphor crystal and proceed with the intended treatment such as secondary particle crushing, for example, a material similar to these in a container such as alumina, silicon nitride, ZrO ₂ , glass, etc. Alternatively, it is preferable that a ball mill treatment is performed for about 10 minutes to 24 hours by inserting a ball such as urethane containing iron core. In this case, you may use 0.05-2 weight% of dispersing agents, such as alkali phosphates, such as organic acid and hexametaphosphoric acid.

Washing treatment The washing treatment can be performed, for example, with water such as deionized water, an organic solvent such as ethanol, or an alkaline aqueous solution such as ammonia water. For the purpose of removing the impurity phase adhering to the surface of the phosphor such as used flux and improving the light emission characteristics, for example, inorganic acids such as hydrochloric acid, nitric acid and sulfuric acid; or organic such as acetic acid An aqueous acid solution can also be used. In this case, it is preferable to further wash with water after washing in an acidic aqueous solution.

As the degree of washing, it is preferable that the pH of the supernatant obtained by dispersing the washed phosphor in water 10 times by weight and allowing it to stand for 1 hour is neutral (about pH 7 to 9). This is because if it is biased toward basicity or acidity, the liquid medium or the like may be adversely affected when mixed with the liquid medium or the like described later.
The degree of washing can also be expressed by the electrical conductivity of the supernatant obtained by dispersing the washed phosphor in 10 times the weight ratio of water and allowing it to stand for 1 hour. The electrical conductivity is preferably as low as possible from the viewpoint of light emission characteristics, but in consideration of productivity, the washing treatment is usually repeated until it is 10 mS / m or less, preferably 5 mS / m or less, more preferably 4 mS / m or less. It is preferable.

  As a method for measuring electrical conductivity, phosphor particles having a specific gravity heavier than water are obtained by stirring and dispersing in water 10 times the weight of the phosphor for a predetermined time, for example, 10 minutes, and then allowing to stand for 1 hour. The electrical conductivity of the supernatant liquid at this time may be measured using an electrical conductivity meter “EC METER CM-30G” manufactured by Toa Decay Co., Ltd. Although there is no restriction | limiting in particular as water used for a washing process and a measurement of electrical conductivity, Demineralized water or distilled water is preferable. Among them, those having particularly low electric conductivity are preferable, and those having a conductivity of usually 0.0064 mS / m or more, and usually 1 mS / m or less, preferably 0.5 mS / m or less are used. The electrical conductivity is usually measured at room temperature (about 25 ° C.).

  In addition, the cleaning treatment can be performed, for example, in the same manner as the cleaning step performed between the first baking step and the second baking step.

Classifying treatment The classification treatment can be performed, for example, by performing a water sieve or chickenpox treatment, or by using various classifiers such as various air classifiers or vibrating sieves. Above all, when dry classification using a nylon mesh is used or a combination of this dry classification and elutriation treatment is used, a phosphor with good dispersibility having a weight median diameter of about 20 μm can be obtained.

  Here, in the water sieving or elutriation treatment, the aqueous medium is usually used to disperse the phosphor particles at a concentration of about 0.1 to 10% by weight in the aqueous medium and to suppress the deterioration of the phosphor. The pH is usually 4 or more, preferably 5 or more, and usually 9 or less, preferably 8 or less. Further, when obtaining phosphor particles having a weight median diameter as described above, in the water sieving and elutriation treatment, for example, particles of 50 μm or less are obtained, and then particles of 30 μm or less are obtained. Is preferable from the viewpoint of balance between work efficiency and yield. Moreover, as a minimum, it is preferable to perform the process of sieving a thing normally 1 micrometer or more, Preferably 5 micrometers or more.

-Surface treatment When producing a light-emitting device by the method described later using the obtained phosphor of the present invention, the phosphor-containing material of the light-emitting device described later is used to further improve the weather resistance such as moisture resistance. In order to improve the dispersibility of the resin in the resin, a surface treatment such as coating the surface of the phosphor with a different substance may be performed as necessary.

  Examples of the substance that can be present on the surface of the phosphor (hereinafter, arbitrarily referred to as “surface treatment substance”) include organic compounds, inorganic compounds, and glass materials.

  Examples of the organic compound include hot-melt polymers such as acrylic resin, polycarbonate, polyamide, and polyethylene, latex, and polyorganosiloxane.

Examples of inorganic compounds include magnesium oxide, aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, tin oxide, germanium oxide, tantalum oxide, niobium oxide, vanadium oxide, boron oxide, antimony oxide, zinc oxide, yttrium oxide, and oxide. Metal oxides such as bismuth; metal nitrides such as silicon nitride and aluminum nitride; orthophosphates such as calcium phosphate, barium phosphate and strontium phosphate; alkali metals such as polyphosphates, combinations of sodium phosphate and calcium nitrate; And / or combinations of alkaline earth metal phosphates and calcium salts; water-soluble fluorides such as NH ₄ F and KHF ₂ ; water-soluble aluminum salts such as aluminum sulfate and the like.

  Examples of the glass material include borosilicate, phosphosilicate, and alkali silicate.

  These surface treatment substances may be used alone or in combination of two or more in any combination and ratio.

The phosphor of the present invention obtained by the above surface treatment is premised on the presence of a surface treatment substance, and examples of the mode include the following.
(I) A mode in which the surface treatment substance constitutes a continuous film and covers the surface of the phosphor.
(Ii) A mode in which the surface treatment substance is coated with the surface of the phosphor by forming a large number of fine particles and adhering to the surface of the phosphor.

  The adhesion amount or the coating amount of the surface treatment substance on the surface of the phosphor is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.1% by weight or more, preferably 1 with respect to the weight of the phosphor. % By weight or more, more preferably 5% by weight or more, further preferably 10% by weight or more, and usually 50% by weight or less, preferably 30% by weight or less, more preferably 20% by weight or less. If the amount of the surface treatment substance with respect to the phosphor is too large, the light emission characteristics of the phosphor may be impaired. If the amount is too small, the surface coating may be incomplete, and the moisture resistance and dispersibility may not be improved.

  Further, the film thickness (layer thickness) of the surface treatment substance formed by the surface treatment is arbitrary as long as the effects of the present invention are not significantly impaired, but is usually 10 nm or more, preferably 50 nm or more, and usually 2000 nm or less, preferably Is 1000 nm or less. If this film thickness is too thick, the light emission characteristics of the phosphor may be impaired. If it is too thin, the surface coating may be incomplete, and the moisture resistance and dispersibility may not be improved.

  The surface treatment method is not particularly limited, and examples thereof include a coating method using a metal oxide (silicon oxide) as described below.

  The phosphor of the present invention is mixed in an alcohol such as ethanol and stirred, and further an alkaline aqueous solution such as ammonia water is mixed and stirred. Next, a hydrolyzable alkyl silicate such as tetraethylorthosilicate is mixed and stirred. The obtained solution is allowed to stand for 3 to 60 minutes, and then the supernatant containing silicon oxide particles that have not adhered to the surface of the phosphor is removed with a dropper or the like. Subsequently, after mixing alcohol, stirring, standing, and removing the supernatant several times, a surface-treated phosphor is obtained through a vacuum drying step at 120 ° C. to 150 ° C. for 10 minutes to 5 hours, for example, 2 hours.

Other methods for surface treatment of the phosphor include, for example, a method in which spherical silicon oxide fine powder is adhered to the phosphor (JP-A-2-209998, JP-A-2-233794), and a phosphor-based silicon compound. A method of attaching a film (Japanese Patent Laid-Open No. 3-231987), a method of coating the surface of phosphor fine particles with polymer fine particles (Japanese Patent Laid-Open No. 6-314593), a phosphor with an organic material, an inorganic material, a glass material, etc. A coating method (Japanese Patent Laid-Open No. 2002-223008), a method of coating a phosphor surface by a chemical vapor reaction method (Japanese Patent Laid-Open No. 2005-82788), and a method of attaching metal compound particles (Japanese Patent Laid-Open No. 2006-2006) No. 28458) can be used.
In addition to the above-described treatment, a generally known technique is used for known phosphors, for example, phosphors used in cathode ray tubes, plasma display panels, fluorescent lamps, fluorescent display tubes, X-ray intensifying screens, and the like. And can be selected as appropriate according to the purpose and application.

[2-4. Use of phosphor]
The phosphor of the present invention can be used for any application that uses the phosphor. In particular, taking advantage of the fact that it can be excited by blue light or near-ultraviolet light, various light emitting devices (see “ The light-emitting device of the invention ") can be suitably used. By adjusting the types and usage ratios of the phosphors to be combined, light emitting devices having various emission colors can be manufactured, and a high-performance white light emitting device can also be realized. The light-emitting device thus obtained can be used as a light-emitting portion (particularly a liquid crystal backlight) or an illumination device of an image display device.
In particular, when the green phosphor of the present invention is used, a white light emitting device can be manufactured by combining an excitation light source that emits blue light and a phosphor that emits orange or red fluorescence (orange or red phosphor). . The emission color in this case can be changed to a desired emission color by adjusting the emission wavelength of the phosphor of the present invention or the combined orange or red phosphor. For example, so-called pseudo white (for example, blue LED and It is also possible to obtain an emission spectrum similar to the emission spectrum of the light emitting device combined with a yellow phosphor. Furthermore, combining this white light-emitting device with a phosphor that emits red fluorescence (red phosphor) realizes a light-emitting device that excels in red color rendering and a light-emitting device that emits light bulb color (warm white). can do. A white light emitting device can also be manufactured by combining the phosphor of the present invention with a phosphor emitting blue fluorescence (blue phosphor) and a red phosphor in an excitation light source that emits near ultraviolet light.

[3. Phosphor-containing composition]
The phosphor of the present invention can be used by mixing with a liquid medium. In particular, when the phosphor of the present invention is used for applications such as a light emitting device, it is preferably used in a form dispersed in a liquid medium, sealed and then cured by heat or light. The phosphor of the present invention dispersed in a liquid medium will be referred to as “the phosphor-containing composition of the present invention” as appropriate.

[3-1. Phosphor]
There is no restriction | limiting in the kind of fluorescent substance of this invention contained in the fluorescent substance containing composition of this invention, It can select arbitrarily from what was mentioned above. Moreover, the fluorescent substance of this invention contained in the fluorescent substance containing composition of this invention may be only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. Furthermore, the phosphor-containing composition of the present invention may contain a phosphor other than the phosphor of the present invention as long as the effects of the present invention are not significantly impaired.

[3-2. Liquid medium]
The liquid medium used in the phosphor-containing composition of the present invention is not particularly limited as long as the performance of the phosphor is not impaired within the intended range. For example, any inorganic material and / or organic material may be used as long as it exhibits liquid properties under the desired use conditions, suitably disperses the phosphor of the present invention, and does not cause an undesirable reaction. it can.

  Examples of the inorganic material include a solution obtained by hydrolyzing a solution containing a metal alkoxide, a ceramic precursor polymer, or a metal alkoxide by a sol-gel method (for example, an inorganic material having a siloxane bond). it can.

  Examples of organic materials include thermoplastic resins, thermosetting resins, and photocurable resins. Specific examples include methacrylic resins such as methyl polymethacrylate; styrene resins such as polystyrene and styrene-acrylonitrile copolymers; polycarbonate resins; polyester resins; phenoxy resins; butyral resins; polyvinyl alcohols; Cellulose-based resins such as cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins.

Among these, in particular, when the phosphor of the present invention is used in a light-emitting device having a high output such as illumination, it is preferable to use a silicon-containing compound as a liquid medium for the purpose of improving heat resistance, light resistance and the like.
The silicon-containing compound refers to a compound having a silicon atom in the molecule, for example, an organic material (silicone material) such as polyorganosiloxane, an inorganic material such as silicon oxide, silicon nitride, silicon oxynitride, and borosilicate. And glass materials such as phosphosilicate and alkali silicate. Among these, silicone materials are preferable from the viewpoint of ease of handling.

The silicone material generally refers to an organic polymer having a siloxane bond as a main chain, and examples thereof include a compound represented by the general composition formula (i) and / or a mixture thereof.
(R ¹ R ² R ³ SiO _1/2 ) _M (R ⁴ R ⁵ SiO _2/2 ) _D (R ⁶ SiO _3/2 ) _T (SiO _4/2 ) _Q Formula (i)
In the general composition formula (i), R ¹ to R ⁶ represent those selected from the group consisting of organic functional groups, hydroxyl groups, and hydrogen atoms. R ¹ to R ⁶ may be the same or different.
In the above formula (i), M, D, T, and Q are numbers that are 0 or more and less than 1, respectively, and that satisfy M + D + T + Q = 1.

  When used for sealing a semiconductor light emitting device, the silicone material can be used after being sealed with a liquid silicone material and then cured by heat or light.

  When silicone materials are classified according to the curing mechanism, silicone materials such as an addition polymerization curing type, a condensation polymerization curing type, an ultraviolet curing type, and a peroxide vulcanization type can be generally cited. Among these, addition polymerization curing type (addition type silicone material), condensation curing type (condensation type silicone material), and ultraviolet curing type are preferable. Hereinafter, the addition type silicone material and the condensation type silicone material will be described.

  The addition-type silicone material refers to a material in which a polyorganosiloxane chain is crosslinked by an organic addition bond. Typical examples include compounds having a Si—C—C—Si bond at the crosslinking point obtained by reacting vinylsilane and hydrosilane in the presence of an addition catalyst such as a Pt catalyst. As these, commercially available products can be used. Specific examples of addition polymerization curing type trade names include “LPS-1400”, “LPS-2410”, and “LPS-3400” manufactured by Shin-Etsu Chemical Co., Ltd.

  On the other hand, examples of the condensation type silicone material include a compound having a Si—O—Si bond obtained by hydrolysis and polycondensation of an alkylalkoxysilane at a crosslinking point. Specific examples thereof include polycondensates obtained by hydrolysis and polycondensation of compounds represented by the following general formula (ii) and / or (iii) and / or oligomers thereof.

M ^{m +} X _n Y ¹ _mn (ii)
(In formula (ii), M represents at least one element selected from silicon, aluminum, zirconium, and titanium, X represents a hydrolyzable group, and Y ¹ represents a monovalent organic group. M represents one or more integers representing the valence of M, and n represents one or more integers representing the number of X groups, provided that m ≧ n.

^{_{(M s + X t Y 1}} s-t-1) u Y 2 (iii)
(In the formula (iii), M represents at least one element selected from silicon, aluminum, zirconium, and titanium, X represents a hydrolyzable group, and Y ¹ represents a monovalent organic group. Y ² represents a u-valent organic group, s represents an integer of 1 or more representing the valence of M, t represents an integer of 1 or more and s−1 or less, u represents 2 or more Represents an integer.)

  Further, the condensation type silicone material may contain a curing catalyst. As this curing catalyst, for example, a metal chelate compound or the like can be suitably used. The metal chelate compound preferably contains one or more of Ti, Ta, and Zr, and more preferably contains Zr. In addition, only 1 type may be used for a curing catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of such condensation type silicone materials include members for semiconductor light emitting devices described in JP-A Nos. 2007-112973 to 112975, JP-A No. 2007-19459, and Japanese Patent Application No. 2006-176468. Is preferred.

Of the condensed silicone materials, particularly preferred materials will be described below.
Silicone-based materials generally have a problem of poor adhesion to semiconductor light-emitting elements, substrates on which the elements are arranged, packages, and the like, but as silicone-based materials having high adhesion, the following features [1] to A condensation type silicone material having one or more of [3] is preferred.

[1] The silicon content is 20% by weight or more.
[2] The solid Si-nuclear magnetic resonance (NMR) spectrum measured by the method described in detail later has at least one peak derived from Si in the following (a) and / or (b).
(A) A peak whose peak top position is in a region where the chemical shift is −40 ppm or more and 0 ppm or less with respect to tetramethoxysilane, and the half width of the peak is 0.3 ppm or more and 3.0 ppm or less.
(B) A peak whose peak top position is in a region where the chemical shift is −80 ppm or more and less than −40 ppm with respect to tetramethoxysilane, and the half width of the peak is 0.3 ppm or more and 5.0 ppm or less.
[3] The silanol content is 0.1% by weight or more and 10% by weight or less.

In the present invention, among the above features [1] to [3], a silicone material having the feature [1] is preferable, a silicone material having the above features [1] and [2] is more preferable, Particularly preferred are silicone materials having all the features [1] to [3].
Hereinafter, the above features [1] to [3] will be described.

[3-2-1. Feature [1] (silicon content)]
The silicon content of the silicone material suitable for the present invention is usually 20% by weight or more, preferably 25% by weight or more, and more preferably 30% by weight or more. On the other hand, the upper limit is usually in the range of 47% by weight or less because the silicon content of the glass composed solely of SiO ₂ is 47% by weight.

  Note that the silicon content of the silicone-based material is calculated based on the results obtained by performing inductively coupled plasma spectroscopy (hereinafter abbreviated as “ICP” as appropriate), for example, using the following method. be able to.

{Measurement of silicon content}
Silicone material is baked in a platinum crucible in the air at 450 ° C. for 1 hour, then at 750 ° C. for 1 hour, and at 950 ° C. for 1.5 hours to remove the carbon component, and then a small amount of residue is obtained. Add more than 10 times the amount of sodium carbonate and heat with a burner to melt, cool this, add demineralized water, and adjust the pH to neutral with hydrochloric acid to a few ppm as silicon. ICP analysis is performed.

[3-2-2. Feature [2] (Solid Si-NMR Spectrum)]
When a solid Si-NMR spectrum of a silicone-based material suitable for the present invention is measured, at least one peak in the peak region of (a) and / or (b) derived from a silicon atom to which a carbon atom of an organic group is directly bonded, Preferably, a plurality of peaks are observed.

When arranged for each chemical shift, in the silicone-based material suitable for the present invention, the half width of the peak described in (a) is generally less than the peak described in (b) described later because molecular motion is less restricted. It is smaller than the case, usually in the range of 3.0 ppm or less, preferably 2.0 ppm or less, and usually 0.3 ppm or more.
On the other hand, the full width at half maximum of the peak described in (b) is usually 5.0 ppm or less, preferably 4.0 ppm or less, and usually 0.3 ppm or more, preferably 0.4 ppm or more.

  If the half-value width of the peak observed in the chemical shift region is too large, the molecular motion is constrained and the strain becomes large, cracks are likely to occur, and the member may be inferior in heat resistance and weather resistance. For example, in the case where a large amount of tetrafunctional silane is used, or in the state where rapid drying is performed in the drying process and a large internal stress is stored, the full width at half maximum is larger than the above range.

In addition, if the half width of the peak is too small, Si atoms in the environment will not be involved in siloxane crosslinking, and heat resistance is higher than that of substances formed mainly from siloxane bonds, such as cases where trifunctional silane remains in an uncrosslinked state. -It may be a member inferior in weather resistance.
However, in a silicone material containing a small amount of Si component in a large amount of organic component, good heat resistance / light resistance and coating performance can be obtained even if the peak of the above-mentioned half width range is observed at -80 ppm or more. There may not be.

  The chemical shift value of the silicone material suitable for the present invention can be calculated based on the results of solid Si-NMR measurement using the following method, for example. In addition, analysis of measurement data (half-width or silanol amount analysis) is performed by a method of dividing and extracting each peak by, for example, waveform separation analysis using a Gaussian function or a Lorentz function.

{Solid Si-NMR spectrum measurement and silanol content calculation}
When performing a solid Si-NMR spectrum about a silicone type material, a solid Si-NMR spectrum measurement and waveform separation analysis are performed on condition of the following. Further, from the obtained waveform data, the half width of each peak is determined for the silicone material. Also, from the ratio of the peak area derived from silanol to the total peak area, the ratio (%) of silicon atoms that are silanols in all silicon atoms is obtained, and the silanol content is determined by comparing with the silicon content analyzed separately. Ask.

{Device conditions}
Apparatus: Chemmagnetics Infinity CMX-400 Nuclear magnetic resonance spectrometer
²⁹ Si resonance frequency: 79.436 MHz
Probe: 7.5 mmφ CP / MAS probe Measurement temperature: room temperature Sample rotation speed: 4 kHz
Measurement method: Single pulse method
¹ H decoupling frequency: 50 kHz
²⁹ Si flip angle: 90 °
²⁹ Si 90 ° pulse width: 5.0μs
Repeat time: 600s
Integration count: 128 Observation width: 30 kHz
Broadening factor: 20Hz
Reference sample: Tetramethoxysilane

  For silicone-based materials, 512 points are taken as measurement data, zero-filled to 8192 points, and Fourier transformed.

{Waveform separation analysis method}
For each peak of the spectrum after Fourier transform, optimization calculation is performed by a non-linear least square method with the center position, height, and half width of the peak shape created by Lorentz waveform and Gaussian waveform or a mixture of both as variable parameters.
In addition, the identification of a peak is AIChE Journal, 44 (5), p. Refer to 1141, 1998, etc.

[3-2-3. Feature [3] (silanol content)]
The silicone material suitable for the present invention has a silanol content of usually 0.1% by weight or more, preferably 0.3% by weight or more, and usually 10% by weight or less, preferably 8% by weight or less, more preferably The range is 5% by weight or less. By reducing the silanol content, the silanol-based material has excellent performance with little change over time, excellent long-term performance stability, and low moisture absorption and moisture permeability. However, since a member containing no silanol is inferior in adhesion, there exists an optimum range for the silanol content as described above.

  The silanol content of the silicone material is, for example, the above [3-2-2. The solid Si-NMR spectrum was measured using the method described in the section of {Characteristic [2] (Solid Si-NMR spectrum)] {Measurement of solid Si-NMR spectrum and calculation of silanol content}. It can be calculated by obtaining the ratio (%) of silicon atoms that are silanols in all silicon atoms from the ratio of the peak area derived from and comparing with the silicon content analyzed separately.

  In addition, since the silicone-based material suitable for the present invention contains an appropriate amount of silanol, the silanol usually bonds with hydrogen at the polar portion present on the device surface, thereby exhibiting adhesion. Examples of the polar part include a hydroxyl group and a metalloxane-bonded oxygen.

  In addition, the silicone material suitable for the present invention is usually heated in the presence of an appropriate catalyst to form a covalent bond by dehydration condensation with the hydroxyl group on the device surface, thereby exhibiting stronger adhesion. can do.

  On the other hand, if there is too much silanol, the inside of the system will thicken and it will be difficult to apply, or it will become more active and solidify before the light-boiling components volatilize by heating, leading to increased foaming and internal stress. It may occur and induce cracks.

[3-3. Content of liquid medium]
The content of the liquid medium is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 50% by weight or more, preferably 75% by weight or more, based on the entire phosphor-containing composition of the present invention. It is 99 weight% or less, Preferably it is 95 weight% or less. When the amount of the liquid medium is large, no particular problem occurs. However, in order to obtain a desired chromaticity coordinate, color rendering index, luminous efficiency, etc. in the case of a semiconductor light emitting device, it is usually at a blending ratio as described above. It is desirable to use a liquid medium. On the other hand, if there is too little liquid medium, there is a possibility that it will be difficult to handle due to lack of fluidity.

  The liquid medium mainly has a role as a binder in the phosphor-containing composition of the present invention. Only one type of liquid medium may be used, but two or more types may be used in any combination and ratio. For example, when a silicon-containing compound is used for the purpose of heat resistance, light resistance, etc., other thermosetting resins such as an epoxy resin may be contained to the extent that the durability of the silicon-containing compound is not impaired. In this case, the content of the other thermosetting resin is usually 25% by weight or less, preferably 10% by weight or less based on the total amount of the liquid medium as the binder.

[3-4. Other ingredients]
The phosphor-containing composition of the present invention may contain other components in addition to the phosphor and the liquid medium as long as the effects of the present invention are not significantly impaired. Moreover, only 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and a ratio.

[3-5. Advantages of phosphor-containing composition]
According to the phosphor-containing composition of the present invention, the phosphor of the present invention can be easily fixed at a desired position. For example, when the phosphor-containing composition of the present invention is used in the production of a light-emitting device, the phosphor-containing composition of the present invention is molded at a desired position and the liquid medium is cured. The phosphor can be sealed, and the phosphor of the present invention can be easily fixed at a desired position.

[4. Light emitting device]
The light-emitting device of the present invention (hereinafter referred to as “light-emitting device” as appropriate) includes a first light-emitting body (excitation light source), and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body. A light-emitting device having at least one of the phosphors of the present invention as the first phosphor.

Specifically, the light-emitting device of the present invention uses an excitation light source as will be described later as the first light emitter, adjusts the type and proportion of the phosphor used as the second light emitter, and is a known device configuration By arbitrarily taking, a light emitting device that emits light in any color can be manufactured.
For example, a white light emitting device is manufactured by combining an excitation light source that emits blue light, a phosphor that emits green fluorescence (green phosphor), and a phosphor that emits orange or red fluorescence (orange or red phosphor). be able to. The emission color in this case can be changed to a desired emission color by adjusting the emission wavelength of the phosphor of the present invention or the phosphor to be combined. For example, so-called pseudo white (for example, blue LED and yellow phosphor) An emission spectrum similar to the emission spectrum of the emission color of the light-emitting device combining the above can also be obtained. Furthermore, combining this white light-emitting device with a phosphor that emits red fluorescence (red phosphor) realizes a light-emitting device that excels in red color rendering and a light-emitting device that emits light bulb color (warm white). can do. Also, a white light emitting device can be manufactured by combining an excitation light source that emits near-ultraviolet light with a phosphor that emits blue fluorescence (blue phosphor), a green phosphor, and a red phosphor.

  Here, the white color of the white light emitting device means all of (yellowish) white, (greenish) white, (blueish) white, (purple) white and white defined by JIS Z 8701 Of these, white is preferred.

Furthermore, if necessary, yellow phosphors (phosphors that emit yellow fluorescence), blue phosphors, orange to red phosphors, other types of green phosphors, etc. It is also possible to manufacture a light emitting device that adjusts and emits light in an arbitrary color.
Only one kind of the phosphor of the present invention may be used, or two or more kinds may be used in any combination and ratio.

  Specifically, the emission peak of the green region in the emission spectrum of the light emitting device of the present invention preferably has an emission peak in the wavelength range of 515 nm to 535 nm, and the emission peak of the red region is 580 nm to 680 nm. Having a light emission peak in the wavelength range of blue, a light emission peak in the blue region having a light emission peak in the wavelength range of 430 nm to 480 nm, and a light emission peak in the yellow region having a light emission peak in the wavelength range of 540 nm to 580 nm. Those having the following are preferred.

  Note that the emission spectrum of the light emitting device is measured by energizing 20 mA with a color / illuminance measurement software and USB2000 series spectroscope (integral sphere specification) manufactured by Ocean Optics in a room maintained at a temperature of 25 ± 1 ° C. It can be carried out. Chromaticity values (x, y, z) can be calculated as chromaticity coordinates in the XYZ color system defined by JIS Z8701 from data in the wavelength region of 380 nm to 780 nm of the emission spectrum. In this case, the relational expression x + y + z = 1 holds. In the present specification, the XYZ color system may be referred to as an XY color system, and is usually expressed as (x, y).

The luminous efficiency is obtained by obtaining the total luminous flux from the result of the emission spectrum measurement using the light emitting device as described above, and dividing the lumen (lm) value by the power consumption (W). The power consumption is obtained by measuring a voltage using a True RMS Multimeters Model 187 & 189 manufactured by Fluke in a state in which 20 mA is energized, and obtaining the product of the current value and the voltage value.
The light emitting device of the present invention has an average color rendering index (Ra) and a special color rendering index R9 of usually 80 or more, preferably 90 or more, more preferably 95 or more.
When the phosphor of the present invention is a phosphor that emits fluorescence in the green region under the irradiation of light from an excitation light source (hereinafter sometimes referred to as “the green phosphor of the present invention”), The light-emitting device of the invention exhibits high luminous efficiency with respect to an excitation light source (first light emitter) that emits light from the near ultraviolet to the blue region, and further, when used in a white light-emitting device such as a light source for a liquid crystal display In addition, the light emitting device is excellent in that the color reproduction range of the display is widened.

  Further, when the green phosphor of the present invention is used in a light emitting device, it is desirable that the CIE chromaticity coordinates x and y based on JIS Z8701 of the emission color satisfy the following regulations. That is, the value of the CIE chromaticity coordinate x of the green phosphor of the present invention is usually 0.100 or more, preferably 0.150 or more, more preferably 0.200 or more, and usually 0.400 or less, preferably Is preferably in the range of 0.380 or less, more preferably 0.360 or less. Further, the CIE chromaticity coordinate y of the green phosphor of the present invention is usually 0.480 or more, preferably 0.490 or more, more preferably 0.495 or more, and usually 0.670 or less, preferably Is preferably in the range of 0.660 or less, more preferably 0.655 or less. When the values of the CIE chromaticity coordinates x and y satisfy the above-described range, there is an advantage that the color reproduction range is widened during white light synthesis.

  When the green phosphor of the present invention is used in a light emitting device, its weight median diameter is usually 0.01 μm or more, preferably 1 μm or more, more preferably 5 μm or more, and further preferably 10 μm or more. Usually, it is preferably 100 μm or less, preferably 30 μm or less, more preferably 20 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of the dispenser to occur.

  In addition, as a measuring method of the emission spectrum of a fluorescent substance, chromaticity coordinate value, and each other physical property value, [2-2. A method similar to that described in the section “Characteristics of phosphor” can be used.

  Moreover, as a preferable specific example of the green phosphor of the present invention used in the light emitting device of the present invention, [2. Examples thereof include the phosphor of the present invention described in the section of “Phosphor” and the phosphor used in each example of the section of “Examples” described later.

  The emission spectrum of the light-emitting device is measured by energizing 20 mA with a color / illuminance measurement software and USB2000 series spectroscope (integral sphere specification) manufactured by Ocean Optics in a room maintained at a temperature of 25 ± 1 ° C. Can be done. Chromaticity values (x, y, z) can be calculated as chromaticity coordinates in the XYZ color system defined by JIS Z8701 from data in the wavelength region of 380 nm to 780 nm of the emission spectrum. In this case, the relational expression x + y + z = 1 holds. In the present specification, the XYZ color system may be referred to as an XY color system, and is usually expressed as (x, y).

  The light-emitting device of the present invention is also characterized by a high NTSC ratio, particularly when a white light-emitting device is used. Specifically, the NTSC ratio (%) of the light emitting device of the present invention is usually 70 or more, preferably 72 or more, more preferably 74 or more. The NTSC ratio is preferably as high as possible, but theoretically it is 150 or less.

In addition, the measuring method of NTSC ratio is as follows.
In the NTSC system, which is the standard of Japanese color TV, the standard R, G, B chromaticity points are defined as follows by the point (x, y) on the CIE chromaticity coordinates.
R (0.67, 0.33), G (0.21, 0.71), B (0.14, 0.08)
When the area of the triangle formed by the three RGB points is 100, the area of the triangle formed by R, G, and B of the display to be obtained, specifically, the display is made to emit monochromatic RGB and the chromaticity ( x, y) is measured, and a value obtained by dividing the area of the triangle obtained by plotting on the CIE chromaticity diagram by the area of the NTSC standard triangle is defined as NTSC ratio (%).

[4-1. Configuration of Light Emitting Device (Light Emitter)]
(First luminous body)
The 1st light-emitting body in the light-emitting device of this invention light-emits the light which excites the 2nd light-emitting body mentioned later.

  The light emission wavelength of the first light emitter is not particularly limited as long as it overlaps with the absorption wavelength of the second light emitter described later, and a light emitter having a wide light emission wavelength region can be used. Usually, an illuminant having an emission wavelength from the ultraviolet region to the blue region is used, and it is particularly preferable to use an illuminant having an emission wavelength from the near ultraviolet region to the blue region.

  As a specific numerical value of the emission peak wavelength of the first illuminant, 200 nm or more is usually desirable. Among these, when near-ultraviolet light is used as excitation light, it is usually 300 nm or more, preferably 330 nm or more, more preferably 360 nm or more, and a light emitter having a peak emission wavelength of usually 420 nm or less is used. desirable. When blue light is used as excitation light, it is usually 420 nm or more, preferably 430 nm or more, and it is desirable to use a light emitter having a peak emission wavelength of usually 500 nm or less, preferably 480 nm or less. Both are from the viewpoint of color purity of the light emitting device.

  As the first light emitter, a semiconductor light emitting element is generally used, and specifically, a light emitting LED, a semiconductor laser diode (hereinafter abbreviated as “LD” as appropriate), or the like can be used. In addition, as a light-emitting body which can be used as a 1st light-emitting body, an organic electroluminescent light emitting element, an inorganic electroluminescent light emitting element, etc. are mentioned, for example. However, what can be used as a 1st light-emitting body is not restricted to what is illustrated by this specification.

Among these, as the first light emitter, a GaN LED or LD using a GaN compound semiconductor is preferable. This is because GaN-based LEDs and LDs have significantly higher light emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely bright with very low power when combined with the phosphor. This is because light emission can be obtained. For example, for a current load of 20 mA, GaN-based LEDs and LDs usually have a light emission intensity 100 times or more that of SiC-based. GaN-based LEDs and LDs preferably have an Al _X Ga _Y N light emitting layer, a GaN light emitting layer, or an In _X Ga _Y N light emitting layer. Among the GaN-based LEDs, those having an In _X Ga _Y N light-emitting layer are particularly preferable because the emission intensity is very strong. In the GaN-based LEDs, a multiple quantum well structure of an In _X Ga _Y N layer and a GaN layer Is particularly preferable because the emission intensity is very strong.

  In the above, the value of X + Y is usually a value in the range of 0.8 to 1.2. In the GaN-based LED, those in which the light emitting layer is doped with Zn or Si or those without a dopant are preferable for adjusting the light emission characteristics.

A GaN-based LED has these light-emitting layer, p-layer, n-layer, electrode, and substrate as basic components, and the light-emitting layer is an n-type and p-type Al _X Ga _Y N layer, GaN layer, or In _X Those having a heterostructure sandwiched between Ga _Y N layers and the like are preferable because of high light emission efficiency, and those having a heterostructure having a quantum well structure are more preferable because of high light emission efficiency.
Note that only one first light emitter may be used, or two or more first light emitters may be used in any combination and ratio.

(Second light emitter)
The second light emitter in the light emitting device of the present invention is a light emitter that emits visible light when irradiated with light from the first light emitter described above, and the phosphor of the present invention described above (for example, the first phosphor) (for example, , A green phosphor), and a second phosphor (a red phosphor, a blue phosphor, an orange phosphor, etc.), which will be described later, as appropriate depending on the application. Further, for example, the second light emitter is configured by dispersing the first and second phosphors in a sealing material.

There is no restriction | limiting in particular in the composition of fluorescent substance other than the fluorescent substance of this invention used in the said 2nd light-emitting body. For example, metal oxides represented by Y ₂ O ₃ , YVO ₄ , Zn ₂ SiO ₄ , Y ₃ Al ₅ O ₁₂ , Sr ₂ SiO _4, etc., which will be the crystal matrix, Sr ₂ Si ₅ N ₈ Metal nitrides typified by, etc., phosphates typified by Ca ₅ (PO ₄ ) ₃ Cl, and sulfides typified by ZnS, SrS, CaS, etc., Y ₂ O ₂ S, La ₂ O ₂ S Ions of rare earth metals such as Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Ag, Cu, Au, Al, Mn, What combined the ion of metals, such as Sb, as an activator element or a coactivator element is mentioned.

Preferred examples of the crystal matrix include sulfides such as (Zn, Cd) S, SrGa ₂ S ₄ , SrS, and ZnS; oxysulfides such as Y ₂ O ₂ S; (Y, Gd) ₃ Al ₅ O ₁₂ , YAlO ₃ , BaMgAl ₁₀ O ₁₇ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ , (Ba, Sr, Ca) (Mg, Zn, Mn) Al ₁₀ O ₁₇ , BaAl ₁₂ O ₁₉ , CeMgAl Aluminates such as ₁₁ O ₁₉ , (Ba, Sr, Mg) O.Al ₂ O ₃ , BaAl ₂ Si ₂ O ₈ , SrAl ₂ O ₄ , Sr ₄ Al ₁₄ O ₂₅ , Y ₃ Al ₅ O ₁₂ ; Y Silicates such as ₂ SiO ₅ and Zn ₂ SiO ₄ ; Oxides such as SnO ₂ and Y ₂ O ₃ ; Borates such as GdMgB ₅ O ₁₀ and (Y, Gd) BO ₃ ; Ca ₁₀ (PO ₄ ) ₆ ( F, Cl _{2, (Sr, Ca, Ba} , Mg) halophosphate such as _{10 (PO 4) 6 Cl 2} ; can be exemplified Sr ₂ P ₂ O 7, the (La, Ce) phosphate PO _4, etc. etc. .

  However, the above-mentioned crystal matrix, activator element and coactivator element are not particularly limited in element composition, and can be partially replaced with elements of the same family, and the obtained phosphor is light in the near ultraviolet to visible region. Any material that absorbs and emits visible light can be used.

  Specifically, the following phosphors can be used, but these are merely examples, and phosphors that can be used in the present invention are not limited to these. In the following examples, as described above, phosphors that differ only in part of the structure are omitted as appropriate.

(First phosphor)
The second light emitter in the light emitting device of the present invention contains at least the above-described phosphor of the present invention as the first phosphor. Any one of the phosphors of the present invention may be used alone, or two or more thereof may be used in any combination and ratio. By using the phosphor of the present invention, the light emission efficiency of the light emitting device can be increased. Furthermore, by utilizing the excellent characteristics of the phosphor of the present invention, it is possible to realize a light-emitting device that has a low luminance efficiency with temperature rise, a high luminance, and a wide color reproduction range.

In addition to the phosphor of the present invention, a phosphor that emits fluorescence of the same color as the phosphor of the present invention (same color combined phosphor) may be used as the first phosphor. For example, when the phosphor of the present invention is a green phosphor, another type of green phosphor can be used together with the phosphor of the present invention as the first phosphor. In the case of an orange or red phosphor, other types of orange or red phosphor can be used together with the phosphor of the present invention as the first phosphor, and the phosphor of the present invention is a blue phosphor. In this case, as the first phosphor, another type of blue phosphor can be used together with the phosphor of the present invention. When the phosphor of the present invention is a yellow phosphor, the first phosphor As the body, other types of yellow phosphors can be used in combination with the phosphor of the present invention.
Any phosphor can be used as long as the effects of the present invention are not significantly impaired.

(Green phosphor)
As the green phosphor, the emission peak wavelength is usually larger than 500 nm, preferably 510 nm or more, more preferably 515 nm or more, and usually 550 nm or less, especially 540 nm or less, further 535 nm or less. Is preferred. If this emission peak wavelength λp is too short, it tends to be bluish, while if it is too long, it tends to be yellowish, and there is a possibility that the characteristics as green light will deteriorate.

In addition, the half-value width of the emission peak of the green phosphor is usually in the range of 40 to 80 nm.
The green phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a weight median diameter is usually 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and usually 30 μm. Hereinafter, it is preferably 20 μm or less, more preferably 15 μm or less. As a specific example, europium-activated alkaline earth silicon oxy represented by (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu composed of fractured particles having a fractured surface and emitting green light. Nitride phosphor, Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu-activated aluminate phosphor such as Eu, (Sr, Ba) Al ₂ Si ₂ O _{8 : Eu, (Ba, Mg)} 2 SiO 4: Eu, (Ba, Sr, Ca, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca) 2 (Mg, Zn) Si 2 O 7: Eu, ( Ba, Ca, Sr, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Eu-activated silicate phosphor such as Eu, Y ₂ SiO ₅ : Ce such as Ce and Tb , Tb-activated silicate phosphor, Sr _{2 2 O 7 -Sr 2 B 2 O} 5: Eu -activated borate phosphate phosphors such as _{Eu, Sr 2 Si 3 O 8} -2SrCl 2: Eu activated halo silicate phosphor such as _Eu, Zn 2 SiO ₄ : Mn activated silicate phosphor such as Mn, CeMgAl ₁₁ O ₁₉ : Tb, Y ₃ Al ₅ O ₁₂ : Tb activated aluminate phosphor such as Tb, Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Tb, La ₃ Ga ₅ SiO ₁₄ : Tb activated silicate phosphor such as Tb, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphor such as Eu, Tb, Sm, Ce activated aluminate phosphors such as Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce, _{Ca 3 Sc 2 Si 3 O 12} : Ce, Ca 3 ( _{c, Mg, Na, Li)} 2 Si 3 O 12: Ce -activated silicate phosphor such as Ce, CaSc ₂ O _4: Ce activated oxide phosphor such as Ce, with Eu such Eu-activated β-sialon Active oxynitride phosphors, BaMgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphors such as Eu and Mn, SrAl ₂ O ₄ : Eu activated aluminate phosphors such as Eu, (La, Gd, Y) ₂ O ₂ S: Tb-activated oxysulfide phosphor such as Tb, LaPO ₄ : Ce, Tb-activated phosphate phosphor such as Ce, Tb, ZnS: Cu, Al, ZnS: Cu, Au, sulfide phosphor such as _{al, (Y, Ga, Lu} , Sc, La) BO 3: Ce, Tb, Na 2 Gd 2 B 2 O 7: Ce, Tb, (Ba, Sr) 2 (Ca, Mg, _{Zn) B 2 O 6: K} , Ce, Ce and Tb such, Tb-activated borate phosphor _{Ca 8 Mg (SiO 4) 4} Cl 2: Eu, Eu such as Mn, Mn-activated halo silicate phosphor, (Sr, Ca, Ba) (Al, Ga, In) 2 S 4: with Eu such Eu Active thioaluminate phosphor, thiogallate phosphor, (Ca, Sr) ₈ (Mg, Zn) (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphor such as Eu, Mn, M ₃ Si ₆ O ₉ N ₄ : Eu, M ₃ Si ₆ O ₁₂ N ₂ : Eu (where M represents an alkaline earth metal element). It is also possible to use Eu-activated oxynitride phosphors such as

In addition, as the green phosphor, it is also possible to use a pyridine-phthalimide condensed derivative, a benzoxazinone-based, a quinazolinone-based, a coumarin-based, a quinophthalone-based, a nartaric imide-based fluorescent dye, or an organic phosphor such as a terbium complex. is there.
Any one of the green phosphors exemplified above may be used, or two or more may be used in any combination and ratio.

The emission peak wavelength λ _p (nm) of the first green phosphor used in the light emitting device of the present invention is usually larger than 500 nm, especially 510 nm or more, more preferably 515 nm or more, and usually 550 nm or less, especially 542 nm. In the following, it is further preferable that the thickness is in the range of 535 nm or less. While this emission peak wavelength lambda _p is the color tends to be bluish green too short, tend to take on too long yellowish, both in some cases the characteristics of the green light decreases.

  In addition, the first green phosphor used in the light emitting device of the present invention generally has a full width at half maximum (hereinafter referred to as “FWHM” as appropriate) in the above-described emission spectrum of 10 nm or more. It is preferably 20 nm or more, more preferably 25 nm or more, further preferably 40 nm or more, and usually 85 nm or less, preferably 80 nm or less, more preferably 75 nm or less, and further preferably 70 nm or less. If the full width at half maximum FWHM is too narrow, the emission intensity may decrease, and if it is too wide, the color purity may decrease.

  The first green phosphor used in the light-emitting device of the invention has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a weight median diameter is usually 1 μm or more, preferably 5 μm or more. The thickness is preferably 10 μm or more, usually 30 μm or less, preferably 20 μm or less, and more preferably 15 μm or less.

(Orange to red phosphor)
When an orange or red phosphor is used as the second phosphor, any orange or red phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the orange to red phosphor is usually in the wavelength range of 570 nm or more, preferably 580 nm or more, more preferably 585 nm or more, and usually 780 nm or less, preferably 700 nm or less, more preferably 680 nm or less. Is preferred.

Examples of such orange to red phosphors include europium composed of broken particles having a red fracture surface and emitting red region (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu. The activated alkaline earth silicon nitride phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the red region (Y, La, Gd, Lu) ₂ O ₂ S: Examples include europium activated rare earth oxychalcogenide phosphors represented by Eu.

  Furthermore, an oxynitride and / or an acid containing at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta, W, and Mo described in JP-A No. 2004-300247 A phosphor containing a sulfide and containing an oxynitride having an alpha sialon structure in which a part or all of the Al element is substituted with a Ga element can also be used in the present invention. These are phosphors containing oxynitride and / or oxysulfide.

In addition, examples of the orange to red phosphor include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu, Y (V, P) O ₄ : Eu, Y ₂ O ₃ : Eu-activated oxide phosphors such as Eu, (Ba, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn-activated silicate fluorescence such as Eu, Mn Eu-activated tungstate such as LiW ₂ O ₈ : Eu, LiW ₂ O ₈ : Eu, Sm, Eu ₂ W ₂ O ₉ , Eu ₂ W ₂ O ₉ : Nb, Eu ₂ W ₂ O ₉ : Sm Phosphor, Eu-activated sulfide phosphor such as (Ca, Sr) S: Eu, Eu-activated aluminate phosphor such as YAlO ₃ : Eu, Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Eu, _{LiY 9 (SiO 4) 6 O} 2: Eu, (Sr, Ba, Ca) 3 SiO 5: _u, Sr 2 BaSiO _5: Eu-activated silicate phosphors such as _{Eu, (Y, Gd) 3} Al 5 O 12: Ce, (Tb, Gd) 3 Al 5 O 12: Ce activated aluminate such as Ce Salt phosphor, (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Mg, Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Mg, Ca, Sr , Ba) AlSi (N, O) ₃ : Eu activated oxide such as Eu, nitride or oxynitride phosphor, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Ce such as Ce Activated oxide, nitride or oxynitride phosphor, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn activated halophosphate phosphor such as Eu, Mn, Ba _{3 MgSi 2 O 8: Eu, Mn} , (Ba, Sr, Ca, Mg) 3 (Zn, Mg) Si 2 _8: Eu, Eu such as Mn, Mn-activated silicate _{phosphor, 3.5MgO · 0.5MgF 2 · GeO 2} : Mn, K 2 TiF 6: Mn 4+ -activated phosphor such as Mn, Eu-activated α Eu-activated oxynitride phosphors such as sialon (Gd, Y, Lu, La) ₂ O ₃ : Eu, Bi-activated oxide phosphors such as Eu and Bi, (Gd, Y, Lu, La) ₂ O ₂ S: Eu, Bi-activated oxysulfide phosphor such as Eu, Bi, (Gd, Y, Lu, La) VO ₄ : Eu, Bi-activated vanadate phosphor such as Eu, Bi, SrY ₂ S ₄ : Eu, Ce activated sulfide phosphors such as Eu and Ce, CaLa ₂ S ₄ : Ce activated sulfide phosphor such as Ce, (Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, _{(Sr, Ca, Ba, Mg} , Zn) 2 P 2 O 7: Eu, Eu such as Mn, Mn-activated phosphate _{Phosphor, (Y, Lu) 2 WO} 6: Eu, Eu such as Mo, Mo-activated tungstate _{phosphor, (Ba, Sr, Ca)} x Si y N z: Eu, Ce ( provided that, x, y , Z represents an integer of 1 or more. Eu, Ce-activated nitride phosphors such as (Ca, Sr, Ba, Mg) ₁₀ (PO ₄ ) ₆ (F, Cl, Br, OH): Eu, Mn-activated halophosphoric acid such as Eu, Mn Salt phosphors, ((Y, Lu, Gd, Tb) _1-xy Sc _x Ce _y ) ₂ (Ca, Mg) _1-r (Mg, Zn) _{2 + r} Si _z-q Ge _q O _{12 + δ and} other Ce It is also possible to use an activated silicate phosphor or the like.

  Examples of red phosphors include β-diketonates, β-diketones, aromatic carboxylic acids, red organic phosphors composed of rare earth element ion complexes having an anion such as Bronsted acid as a ligand, and perylene pigments (for example, Dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene), anthraquinone pigment, Lake pigments, azo pigments, quinacridone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments, indophenol pigments, It is also possible to use a cyanine pigment or a dioxazine pigment.

Among these, as the red phosphor, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Ca, Sr , Ba) AlSi (N, O) ₃ : Eu, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu, (La, Y) ₂ O ₂ S: Eu or containing Eu complex More preferably, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Ca, Sr, Ba) AlSi (N, O) ₃ : Eu, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu or (La, Y) ₂ O ₂ S: Eu, or Eu (dibenzoylmethane) _3. Β-diketone Eu complex such as 1,10-phenanthroline complex or carboxylic acid E Preferably containing _{complexes, (Ca, Sr, Ba)} 2 Si 5 (N, O) 8: Eu, (Sr, Ca) AlSi (N, O) 3: Eu or _{(La, Y) 2 O 2} S : Eu is particularly preferred.

Among the above examples, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Sr, Ba) ₃ SiO ₅ : Eu are preferable as the orange phosphor.
In addition, orange or red fluorescent substance may use only 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

(Blue phosphor)
When a blue phosphor is used as the second phosphor, any blue phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the blue phosphor is usually 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 490 nm or less, preferably 480 nm or less, more preferably 470 nm or less, and further preferably 460 nm or less. It is preferable to be in the wavelength range.

Further, the half-value width of the emission peak of the blue phosphor is usually in the range of 20 to 80 nm.
The blue phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a weight median diameter is usually 1 μm or more, preferably 5 μm or more, more preferably 10 mμ or more, and usually 30 μm. Hereinafter, it is preferably 20 μm or less, more preferably 15 μm or less.

Such a blue phosphor is composed of growing particles having a substantially hexagonal shape as a regular crystal growth shape, and europium represented by (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu that emits light in a blue region. The activated barium magnesium aluminate phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the blue region (Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ ( Cl, F): a europium-activated calcium halophosphate phosphor represented by Eu, composed of grown particles having a substantially cubic shape as a regular crystal growth shape, and emits light in a blue region (Ca, Sr, Ba) ₂ Europium-activated alkaline earth chloroborate phosphor represented by B ₅ O ₉ Cl: Eu, fractured particles having a fracture surface Europium-activated alkaline earth aluminate represented by (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba) ₄ Al ₁₄ O ₂₅ : Eu System phosphors and the like.

In addition, as the blue phosphor, Sn-activated phosphate phosphor such as Sr ₂ P ₂ O ₇ : Sn, (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba) ₄ Al ₁₄ O ₂₅ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Tb, Sm, BaAl ₈ O ₁₃ : with Eu, etc. Active aluminate phosphor, Ce-activated thiogallate phosphor such as SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce, Eu, Mn such as (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn Active aluminate phosphor, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Ca) ₅ (PO ₄ ) ₃ (Cl, F, Br, OH): Eu, Mn Eu-activated halophosphate phosphor such as Sb, Sb, BaAl ₂ Si ₂ O ₈ : Eu, (Sr, Ba) ₃ MgSi ₂ O ₈ : Eu-activated silicate phosphor such as Eu, Sr ₂ P ₂ O ₇ : Eu-activated phosphate phosphors such as Eu, sulfide phosphors such as ZnS: Ag, ZnS: Ag, Al, Ce-activated silicate phosphors such as Y ₂ SiO ₅ : Ce, tungsten such as CaWO _{4 phosphors, (Ba, Sr, Ca)} BPO 5: Eu, Mn, (Sr, Ca) 10 (PO 4) 6 · nB 2 O 3: Eu, 2SrO · 0.84P 2 O 5 · 0.16B ₂ O ₃ : Eu, Mn activated borate phosphate phosphor such as Eu, Sr ₂ Si ₃ O ₈ · 2SrCl ₂ : Eu activated halosilicate phosphor such as Eu, SrSi ₉ Al ₁₉ ON ₃₁ : Eu, EuSi ₉ Al ₁₉ Eu-activated of ON _31, etc. Nitride _{phosphor, La 1-x Ce x Al} (Si 6-z Al z) (N 10-z O z) ( here, x, and y are each 0 ≦ x ≦ 1,0 ≦ z ≦ 6 is a number _{satisfying.), La 1-x-} y Ce x Ca y Al (Si 6-z Al z) (N 10-z O z) ( here, x, y, and z are each 0 It is also possible to use Ce-activated oxynitride phosphors such as ≦ x ≦ 1, 0 ≦ y ≦ 1, and 0 ≦ z ≦ 6.

  In addition, as the blue phosphor, for example, naphthalic acid imide-based, benzoxazole-based, styryl-based, coumarin-based, pyralizone-based, triazole-based compound fluorescent dyes, thulium complexes and other organic phosphors can be used. .

Among the above examples, as the blue phosphor, (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu or It is preferable to contain (Ba, Ca, Mg, Sr) ₂ SiO ₄ : Eu, and (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (PO Cl, F) ₂ : Eu or (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu is more preferable, and BaMgAl ₁₀ O ₁₇ : Eu, Sr ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : More preferably, Eu or Ba ₃ MgSi ₂ O ₈ : Eu is included. Of these, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu or (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu is particularly preferred for illumination and display applications.
In addition, only 1 type may be used for blue fluorescent substance and it may use 2 or more types together by arbitrary combinations and a ratio.

(Yellow phosphor)
When a yellow phosphor is used as the second phosphor, any yellow phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the yellow phosphor is usually in the wavelength range of 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. Is preferred.

Further, the half-value width of the emission peak of the yellow phosphor is usually in the range of 60 nm to 200 nm.
The yellow phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a weight median diameter is usually 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and usually 30 μm. Or less, preferably 20 μm or less, more preferably 15 μm or less

Examples of such yellow phosphors include various oxide-based, nitride-based, oxynitride-based, sulfide-based, and oxysulfide-based phosphors.
In particular, RE ₃ M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M represents Al, Ga, and Sc. And M ^a ₃ M ^b ₂ M ^c ₃ O ₁₂ : Ce (where M ^a is a divalent metal element and M ^b is a trivalent metal element) , ^{M c} represents a tetravalent metal element) garnet phosphor having a garnet structure represented by ^{_{like, AE 2 M d O 4:}} . Eu ( where, AE is, Ba, Sr, Ca, Mg , and An orthosilicate phosphor represented by at least one element selected from the group consisting of Zn, M ^d represents Si and / or Ge, and the like, oxygen of constituent elements of the phosphors of these systems Acid in which a part of Compound _{phosphor, AEAlSi (N, O) 3} : Ce (. Here, AE is, Ba, represents Sr, Ca, at least one element selected from the group consisting of Mg and Zn) CaAlSiN ₃ such structure Phosphors activated with Ce, such as nitride-based phosphors having the above.

In addition, as yellow phosphors, sulfide-based fluorescence such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu, etc. Body, Ca _x (Si, Al) ₁₂ (O, N) ₁₆ : Eu-activated phosphor such as an oxynitride-based phosphor having a SiAlON structure such as Eu, an alkaline earth metal element It is also possible to use a rare earth activated phosphor having a good La ₃ Si ₆ N ₁₁ structure.

Examples of the yellow phosphor include fluorescent dyes such as brilliant sulfoflavine FF (Colour Index Number 56205), basic yellow HG (Colour Index Number 46040), eosine (Colour Index Number 45380), rhodamine 6G (Colour Index Number 45160), etc. Etc. can also be used.
In addition, yellow fluorescent substance may use only 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

(Second phosphor)
The second light emitter in the light emitting device of the present invention may contain a phosphor (that is, a second phosphor) in addition to the first phosphor described above, depending on the application. This second phosphor is a phosphor having an emission peak wavelength different from that of the first phosphor. Usually, since these second phosphors are used to adjust the color tone of light emitted from the second light emitter, the second phosphor emits fluorescence having a color different from that of the first phosphor. Often phosphors are used.
As described above, when a green phosphor is used as the first phosphor, examples of the second phosphor include other than a green phosphor such as an orange to red phosphor, a blue phosphor, and a yellow phosphor. A phosphor is used. When an orange or red phosphor is used as the first phosphor, examples of the second phosphor include phosphors other than orange or red phosphors such as a green phosphor, a blue phosphor, and a yellow phosphor. Use. When a blue phosphor is used as the first phosphor, a phosphor other than a blue phosphor such as a green phosphor, an orange to red phosphor, or a yellow phosphor is used as the second phosphor. When a yellow phosphor is used as the first phosphor, a phosphor other than a yellow phosphor such as a green phosphor, an orange to red phosphor, or a blue phosphor is used as the second phosphor.
Examples of the green phosphor, orange to red phosphor, blue phosphor, and yellow phosphor include the same phosphors as described in the section of the first phosphor.

  The weight median diameter of the second phosphor used in the light emitting device of the present invention is usually 10 μm or more, preferably 12 μm or more, and usually 30 μm or less, preferably 25 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of the dispenser to occur.

(Combination of second phosphors)
As the second phosphor, only one kind of phosphor may be used, or two or more kinds of phosphors may be used in any combination and ratio. Further, the ratio between the first phosphor and the second phosphor is also arbitrary as long as the effects of the present invention are not significantly impaired. Therefore, the usage amount of the second phosphor, the combination and ratio of the phosphors used as the second phosphor, and the like may be arbitrarily set according to the use of the light emitting device.

  In addition, the phosphor of the present invention is mixed with other phosphors (here, mixing does not necessarily mean that the phosphors need to be mixed with each other, but means that different types of phosphors are combined). ) Can be used. In particular, when phosphors are mixed in the combination described above, a preferable phosphor mixture is obtained. In addition, there is no restriction | limiting in particular in the kind and the ratio of the fluorescent substance to mix.

  In the light emitting device of the present invention, the presence / absence and type of the second phosphor described above may be appropriately selected according to the use of the light emitting device. For example, when the light emitting device of the present invention is configured as a green light emitting device, only the green phosphor may be used as the first phosphor, and the use of the second phosphor is usually unnecessary.

  On the other hand, when the light emitting device of the present invention is configured as a white light emitting device using a green phosphor as the first phosphor, the first phosphor, the first phosphor, and the second phosphor. Specific examples of preferable combinations with the body include the following combinations (i) to (iii).

(I) A blue phosphor (such as a blue LED) is used as the first phosphor, a green phosphor (such as the phosphor of the present invention) is used as the first phosphor, and red fluorescence is used as the second phosphor. Use the body. In this case, the red phosphor is preferably one or two or more red phosphors selected from the group consisting of K ₂ TiF ₆ : Mn and (Sr, Ca) AlSi (N, O) ₃ : Eu.

(Ii) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a green phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second phosphor is used as the second phosphor. A blue phosphor and a red phosphor are used in combination. In this case, the blue phosphor is selected from the group consisting of (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu and (Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ (Cl, F): Eu. One or more blue phosphors are preferred. Further, as the red _{phosphor, (Sr, Ca) AlSiN 3} : Eu and _La 2 _O 2 S: one or more than one kind of red phosphor selected from the group consisting of Eu is preferred. Among them, a near ultraviolet LED, the phosphor of the present invention, BaMgAl ₁₀ O ₁₇ : Eu as a blue phosphor, and (Sr, Ca) AlSi (N, O) ₃ : Eu as a red phosphor are used in combination. Is preferred.

(Iii) A blue phosphor (such as a blue LED) is used as the first phosphor, a green phosphor (such as the phosphor of the present invention) is used as the first phosphor, and orange fluorescence is used as the second phosphor. Use the body. In this case, as the orange phosphor, one or more orange phosphors selected from the group consisting of (Sr, Ca) AlSi (N, O) ₃ : Ce and (Sr, Ba) ₃ SiO ₅ : Eu are used. preferable.

(Sealing material)
In the light emitting device of the present invention, the first and / or second phosphors are usually used by being dispersed in a liquid medium that is a sealing material. Examples of the liquid medium include [3. Examples thereof are the same as those described in the section “Fluorescent substance-containing composition”.

  The liquid medium can contain a metal element that can be a metal oxide having a high refractive index in order to adjust the refractive index of the sealing member. Examples of metal elements that give a metal oxide having a high refractive index include Si, Al, Zr, Ti, Y, Nb, and B. These metal elements may be used alone or in combination of two or more in any combination and ratio.

  The presence form of such a metal element is not particularly limited as long as the transparency of the sealing member is not impaired. For example, even if a uniform glass layer is formed as a metalloxane bond, the metal element is present in a particulate form in the sealing member. It may be. When present in the form of particles, the structure inside the particles may be either amorphous or crystalline, but is preferably a crystalline structure in order to provide a high refractive index. Further, the particle diameter is usually not more than the emission wavelength of the semiconductor light emitting device, preferably not more than 100 nm, more preferably not more than 50 nm, particularly preferably not more than 30 nm so as not to impair the transparency of the sealing member. For example, by mixing particles of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, yttrium oxide, niobium oxide, etc. with a silicone-based material, the metal element can be present in the sealing member in the form of particles. .

  The liquid medium may further contain known additives such as a diffusing agent, a filler, a viscosity modifier, and an ultraviolet absorber. In addition, only 1 type may be used for these additives, and 2 or more types may be used together by arbitrary combinations and a ratio.

[4-2. Configuration of light emitting device (others)]
The other configurations of the light emitting device of the present invention are not particularly limited as long as the first light emitting body and the second light emitting body described above are provided. Usually, the first light emitting body described above is formed on an appropriate frame. And a second light emitter. At this time, the second light emitter is excited by the light emission of the first light emitter (that is, the first and second phosphors are excited) to emit light, and the first light emitter emits light. And / or it arrange | positions so that light emission of a 2nd light-emitting body may be taken out outside. In this case, the first phosphor and the second phosphor are not necessarily mixed in the same layer. For example, the second phosphor is contained on the layer containing the first phosphor. For example, the phosphor may be contained in a separate layer for each color development of the phosphor, such as by stacking layers.

  In the light emitting device of the present invention, members other than the above-described excitation light source (first light emitter), phosphor (second light emitter), and frame may be used. Examples thereof include the aforementioned sealing materials. In addition to the purpose of dispersing the phosphor (second light emitter) in the light emitting device, the sealing material is provided between the excitation light source (first light emitter), the phosphor (second light emitter), and the frame. It can be used for the purpose of bonding.

[4-3. Embodiment of Light Emitting Device]
Hereinafter, the light-emitting device of the present invention will be described in more detail with reference to specific embodiments. However, the present invention is not limited to the following embodiments, and does not depart from the gist of the present invention. It can be implemented with arbitrary modifications.

  FIG. 1 is a schematic perspective view showing a positional relationship between a first light emitter serving as an excitation light source and a second light emitter configured as a phosphor containing portion having a phosphor in an example of the light emitting device of the present invention. Shown in In FIG. 1, reference numeral 1 denotes a phosphor-containing portion (second light emitter), reference numeral 2 denotes a surface-emitting GaN-based LD as an excitation light source (first light emitter), and reference numeral 3 denotes a substrate. In order to create a state in which they are in contact with each other, LD (2) and phosphor-containing portion (second light emitter) (1) are produced separately, and their surfaces are brought into contact with each other by an adhesive or other means. Alternatively, the phosphor-containing portion (second light emitter) may be formed (molded) on the light emitting surface of the LD (2). As a result, the LD (2) and the phosphor-containing portion (second light emitter) (1) can be brought into contact with each other.

  When such an apparatus configuration is employed, the light loss is such that light from the excitation light source (first light emitter) is reflected by the film surface of the phosphor-containing portion (second light emitter) and oozes out. Therefore, the light emission efficiency of the entire device can be improved.

  FIG. 2A is a typical example of a light emitting device of a form generally referred to as a shell type, and has a light emission having an excitation light source (first light emitter) and a phosphor-containing portion (second light emitter). It is typical sectional drawing which shows one Example of an apparatus. In the light emitting device (4), reference numeral 5 is a mount lead, reference numeral 6 is an inner lead, reference numeral 7 is an excitation light source (first light emitter), reference numeral 8 is a phosphor-containing resin portion, reference numeral 9 is a conductive wire, reference numeral Reference numeral 10 denotes a mold member.

  FIG. 2B is a typical example of a light-emitting device of a form called a surface-mount type, and has light emission having an excitation light source (first light emitter) and a phosphor-containing portion (second light emitter). It is typical sectional drawing which shows one Example of an apparatus. In the figure, reference numeral 22 is an excitation light source (first light emitter), reference numeral 23 is a phosphor-containing resin portion as a phosphor-containing portion (second light emitter), reference numeral 24 is a frame, reference numeral 25 is a conductive wire, Reference numerals 26 and 27 indicate electrodes.

[4-4. Application of light emitting device]
The application of the light-emitting device of the present invention is not particularly limited and can be used in various fields where ordinary light-emitting devices are used. However, since the color reproduction range is wide and the color rendering property is high, illumination is particularly important. It is particularly preferably used as a light source for a device or an image display device.

[4-4-1. Lighting device]
When the light-emitting device of the present invention is applied to a lighting device, the above-described light-emitting device may be appropriately incorporated into a known lighting device. For example, a surface emitting illumination device (11) incorporating the above-described light emitting device (4) as shown in FIG. 3 can be mentioned.

  FIG. 3 is a cross-sectional view schematically showing one embodiment of the illumination device of the present invention. As shown in FIG. 3, the surface-emitting illumination device has a number of light-emitting devices (13) (described above) on the bottom surface of a rectangular holding case (12) whose inner surface is light-opaque such as a white smooth surface. The light emitting device (4) corresponds to the lid portion of the holding case (12) by arranging a power source and a circuit (not shown) for driving the light emitting device (13) on the outside thereof. A diffuser plate (14) such as a milky white acrylic plate is fixed at a location for uniform light emission.

  Then, the surface emitting illumination device (11) is driven to apply light to the excitation light source (first light emitter) of the light emitting device (13) to emit light, and part of the light emission is converted into the phosphor. The phosphor in the phosphor-containing resin part as the containing part (second light emitter) absorbs and emits visible light, while having high color rendering due to color mixing with blue light or the like that is not absorbed by the phosphor. Luminescence is obtained, and this light is transmitted through the diffusion plate (14) and emitted upward in the drawing, so that illumination light with uniform brightness can be obtained within the surface of the diffusion plate (14) of the holding case (12). Become.

[4-4-2. Image display device]
When the light emitting device of the present invention is used as a light source of an image display device, the specific configuration of the image display device is not limited, but it is preferably used with a color filter. For example, when the image display device is a color image display device using color liquid crystal display elements, the light emitting device is used as a backlight, a light shutter using liquid crystal, and a color filter having red, green, and blue pixels; By combining these, an image display device can be formed.

The color reproduction range by light after passing through the color filter at this time is usually 60% or more, preferably 80% or more, more preferably 90% or more, more preferably 100% or more, and usually 150% in terms of NTSC ratio. It is as follows.
The amount of light transmitted from each color filter (light utilization efficiency) relative to the amount of light transmitted from the entire color filter is usually 20% or more, preferably 25% or more, more preferably 28% or more, Preferably it is 30% or more. The higher the utilization efficiency, the better, but it is usually 33% or less because of the use of three filters of red, green and blue.

[5. Sintered body]
The sintered body (silicon nitride ceramics) obtained by sintering the silicon nitride of the present invention has a white body color and has translucency or transparency. Silicon nitride ceramics can be deployed in many applications such as sodium lamps, high-power laser bases, bulletproof glass, and high-temperature furnace viewing windows because they are superior in thermal shock resistance and mechanical properties to alumina ceramics.

[5-1. Method for producing sintered body]
There is no restriction | limiting in particular as a method of manufacturing a sintered compact using the silicon nitride powder of this invention, For example, (1) Hot press method, (2) Atmospheric pressure sintering method, (3) Atmospheric pressure sintering And (4) known methods using an oxide such as MgO, Al ₂ O ₃ , Y ₂ O ₃ as a sintering aid, such as the HIP method, can be arbitrarily used. Among these, the method (3) or (4) is preferred because a high-density sintered body is easily obtained.

[6. Pigment]
The silicon nitride of the present invention has a high reflectance and can be used as a white pigment. The white pigment can be used together with other pigments or additives in known pigment applications such as paints, heat shielding materials, and cosmetics. As the average primary particle size when the pigment is dispersed, a known pulverization / dispersion method may be applied so as to be in an appropriate range according to each of these uses. It is preferable that

  Hereinafter, the embodiments of the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following embodiments, and various modifications may be made within the scope of the invention. it can.

[Measurement and evaluation method of phosphor]
In Examples, Comparative Examples, and Reference Examples described later, various evaluations of the phosphor particles were performed by the following methods unless otherwise specified.

[Measurement method of emission spectrum]
The emission spectrum was measured using a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a 150 W xenon lamp as an excitation light source and a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus. The light from the excitation light source was passed through a diffraction grating spectrometer having a focal length of 10 cm, and only the excitation light having a wavelength of 405 nm or 455 nm was irradiated to the phosphor through the optical fiber. The light generated from the phosphor by the irradiation of excitation light is dispersed by a diffraction grating spectroscope having a focal length of 25 cm, the emission intensity of each wavelength is measured by a spectrum measuring device in a wavelength range of 300 nm to 800 nm, and a personal computer is used. An emission spectrum was obtained through signal processing such as sensitivity correction. During the measurement, the slit width of the light-receiving side spectroscope was set to 1 nm and the measurement was performed.

  Further, the emission peak wavelength and the half width were read from the obtained emission spectrum. The emission peak intensity and luminance were expressed as relative values with the peak intensity when LP-B4 manufactured by Kasei Optonix Co., Ltd. was excited at a wavelength of 365 nm as a reference value of 100. It is preferable that the relative emission peak intensity and luminance are higher.

[Measurement method of chromaticity coordinates]
Chromaticity coordinates in the XYZ color system defined by JIS Z8701 from data in the wavelength region of 430 nm to 800 nm (excitation wavelength of 405 nm) or 480 nm to 800 nm (excitation wavelength of 455 nm) in accordance with JIS Z8724 CIEx and CIEy were calculated.

[Measurement method of excitation spectrum]
A fluorescence spectrophotometer F-4500 manufactured by Hitachi, Ltd. was used, and the wavelength was monitored according to the emission peak wavelength to obtain an excitation spectrum in the wavelength range of 250 nm to 500 nm.

[Temperature extinction characteristics (emission intensity maintenance rate and luminance maintenance rate)]
Measurement was performed using an MCPD7000 multi-channel spectrum measurement device manufactured by Otsuka Electronics as a light emission spectrum measurement device, a stage equipped with a cooling mechanism using a Peltier element and a heating mechanism using a heater, and a device equipped with a 150 W xenon lamp as a light source.

A cell containing a phosphor sample was placed on the stage, and the temperature was changed in the range of 20 ° C to 175 ° C. That is, after confirming that the surface temperature of the phosphor is constant at 20 ° C., 25 ° C., 50 ° C., 75 ° C., 100 ° C., 125 ° C., 150 ° C., or 175 ° C., the diffraction from the light source is performed at each temperature. An emission spectrum was measured by exciting the phosphor with light having a wavelength of 455 nm extracted by spectroscopy with a grating. The emission peak intensity and the emission luminance were determined from the measured emission spectrum, and the emission peak intensity and the emission luminance value at each temperature were calculated at a ratio when the emission peak intensity and the emission luminance value at 20 ° C. were 100.
In addition, the measured value of the surface temperature of the phosphor on the excitation light irradiation side was a value corrected using the measured temperature value by a radiation thermometer and a thermocouple.

[Internal quantum efficiency, external quantum efficiency, and absorption efficiency]
The absorption efficiency αq, internal quantum efficiency ηi, and external quantum efficiency ηo of the phosphor were determined as follows.
First, the phosphor sample to be measured was packed in a cell with a sufficiently smooth surface so that the measurement accuracy was maintained, and was attached to an integrating sphere.

  Light was introduced into this integrating sphere from an emission light source (150 W Xe lamp) for exciting the phosphor using an optical fiber. The emission peak wavelength of light from the light emission source was adjusted using a monochromator (diffraction grating spectrometer) or the like so as to be monochromatic light of 455 nm. Using this monochromatic light as excitation light, the phosphor sample to be measured was irradiated, and the spectrum was measured for the emission (fluorescence) and reflected light of the phosphor sample using a spectrometer (MCPD7000 manufactured by Otsuka Electronics Co., Ltd.). The light in the integrating sphere was guided to a spectroscopic measurement device using an optical fiber.

The absorption efficiency αq is a value obtained by dividing the number of photons N _abs of the excitation light absorbed by the phosphor sample by the total number of photons N of the excitation light.

First, the total number of photons N of the latter excitation light is proportional to the numerical value obtained by the following (formula A). Therefore, a “Spectralon” manufactured by Labsphere, which is a reflector having a reflectance R of approximately 100% with respect to the excitation light (having a reflectance R of 99% with respect to the excitation light having a wavelength of 450 nm), is used as a measurement target. The reflection spectrum I _ref (λ) was measured by attaching to the above integrating sphere with the same arrangement as the phosphor sample, irradiating with excitation light, and measuring with a spectroscopic measurement device, and the value of the following (formula A) was obtained. .

Here, the integration interval was 410 nm to 480 nm.
The number N _abs of the photons in the excitation light that is absorbed in the phosphor sample is proportional to the amount calculated by the following equation (B).

Therefore, the reflection spectrum I (λ) was obtained when the phosphor sample for which the absorption efficiency αq is to be obtained was attached. The integration range of (Formula B) was the same as the integration range defined in (Formula A). Since the actual spectrum measurement value is generally obtained as digital data divided by a certain finite bandwidth with respect to λ, the integration of (Equation A) and (Equation B) was obtained by the sum based on the bandwidth. .
From the above, αq = N _abs / N = (Formula B) / (Formula A) was calculated.

Next, the internal quantum efficiency ηi was determined as follows. The internal quantum efficiency ηi is a value obtained by dividing the number N _PL of photons derived from the fluorescence phenomenon by the number N _abs of photons absorbed by the phosphor sample.
Here, _NPL is proportional to the amount obtained by the following (formula C). Therefore, the amount required by the following (formula C) was determined.

The integration interval was 481 nm to 800 nm.
As described above, ηi = (formula C) / (formula B) was calculated, and the internal quantum efficiency ηi was obtained.

It should be noted that the integration from the spectrum that was converted to digital data was performed in the same manner as when the absorption efficiency αq was obtained.
And the external quantum efficiency (eta) o was calculated | required by taking the product of absorption efficiency (alpha) q calculated | required as mentioned above and internal quantum efficiency (eta) i.

[Weight median diameter]
Using a laser diffraction / scattering particle size distribution measuring apparatus LA-300 manufactured by HORIBA, the measurement was performed using water as a dispersion medium.

[Powder X-ray diffraction measurement]
Powder X-ray diffraction was precisely measured with a powder X-ray diffractometer X'Pert manufactured by PANalytical. The measurement conditions are as follows. The measurement data was subjected to automatic background processing using data processing software X'Pert High Score (manufactured by PANalytical) with a bending filter of 5.
Using CuKα tube X-ray output = 45 KV, 40 mA
Divergence slit = 1/4 °, X-ray mirror detector = semiconductor array detector X 'Celerator used, Ni filter used Scanning range 2θ = 10 to 65 degrees Reading width = 0.05 degrees Counting time = 33 seconds

[LED durability test]
This will be described with reference to FIG. A blue light emitting diode (C460EZ290: manufactured by Cree) was used as the first light emitter (22), and die bonding was performed using a silver paste as an adhesive on the electrode (27) at the bottom of the recess of the frame. After heating at 150 ° C. for 2 hours to cure the silver paste, the blue LED (22) and the electrode (26) of the frame (24) were wire-bonded. A gold wire with a diameter of 25 μm was used as the wire.
To 0.08 g of each phosphor dried at 150 ° C. for 2 hours, 1.415 g of silicon resin (SCR1011: manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed to prepare a phosphor slurry. The slurry was poured into the concave portion of the frame and cured by heating at 70 ° C. for 1 hour and further at 150 ° C. for 5 hours to form a phosphor-containing portion (23), thereby producing a surface-mount green light emitting device.
The obtained light emitting device was driven to emit light by energizing the blue LED with 20 mA in an environment of a temperature of 85 ° C. and a humidity of 85%. The CIEy value, which is a chromaticity coordinate having a high influence on green, was measured every 50 hours, and the ratio when the value immediately after the start of energization was taken as 100 was determined as the CIEy retention rate.

[Measurement method of reflection spectrum]
For the reflection spectrum, a 150 W xenon lamp was used as the excitation light source, an integrating sphere was used as the condensing device, and an MCPD7000 multi-channel spectrum measuring device manufactured by Otsuka Electronics was used as the spectrum measuring device. First, as a standard white plate, a material having a reflectance R of almost 100% with respect to excitation light, “Spectralon” manufactured by Labsphere (having a reflectance R of 99% with respect to excitation light having a wavelength of 450 nm), and a 150 W xenon lamp. The spectrum was measured in the wavelength range of 380 nm to 780 nm, the reflection intensity of each wavelength was measured, and a reflection spectrum was obtained through signal processing such as sensitivity correction by a personal computer. Next, the silicon nitride sample to be measured is packed in a cell with a sufficiently smooth surface so that measurement accuracy can be maintained, and the reflection intensity of each wavelength is measured by the same method, and the reflection from the standard white plate is measured. The reflection spectrum of the sample was obtained from the intensity ratio.

[Measurement method of object color]
Object color L ^* a ^* b ^* method measurements Konica Minolta color difference meter CR-300, was used D ₆₅ as a light source. First, white calibration was performed by placing the standard calibration plate through a transparent glass plate and the measuring head portion perpendicular to the standard calibration plate. Next, the phosphor sample to be measured was packed in a cell with a sufficiently smooth surface so that measurement accuracy was maintained, and an object color was obtained by measuring in the same manner via a transparent glass plate. .

[Example 1]
A boron nitride crucible was charged in 300 g of α-Si ₃ N ₄ (Ube Industries' SN-E10), and the boron nitride crucible was placed in a resistance heating type vacuum heat treatment furnace (manufactured by Fuji Denpa Kogyo). Under reduced pressure of 5 × 10 ⁻³ Pa, vacuum heating was performed from room temperature to 800 ° C. at a heating rate of 20 ° C./min. When the temperature reached 800 ° C., the temperature was maintained and high-purity nitrogen gas (99.9995%) was introduced for 30 minutes until the pressure became 0.92 MPa, and then the temperature was further increased while maintaining 0.92 MPa. The temperature was raised to 1200 ° C. at a rate of 20 ° C./min. The temperature was maintained for 5 minutes, and the thermocouple was changed to a radiation thermometer. Further, the temperature was increased to 2000 ° C. at a rate of temperature increase of 20 ° C./min. Thereafter, it was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, then allowed to cool, and subjected to a sieving treatment to collect particles having a particle size of 250 μm or less.

The reflection spectrum of the obtained β-Si ₃ N ₄ is shown in FIG. 4, and the powder X-ray diffraction measurement result is shown in FIG. Table 1 shows the reflectance obtained from the above, the results of measuring the carbon content by a high-frequency furnace heating combustion extraction-non-dispersive infrared detection method (Horiba Seisakusho, EMIA520FA type), and visual body color.

[Example 2]
α-Si ₃ N ₄ (Ube Industries, Ltd. SN-E10) was screened to separate particles having a particle size of 250 μm or less, and 250 g of this powder was charged into a boron nitride crucible, and the same method as in Example 1 was performed. Then, heat treatment was performed.
The reflection spectrum of the silicon nitride is shown in FIG. 4, and the X-ray diffraction pattern is shown in FIG. Table 1 shows the reflectance obtained from the above, the results of measuring the carbon content by a high-frequency furnace heating combustion extraction-non-dispersive infrared detection method (Horiba Seisakusho, EMIA520FA type), and visual body color.

[Examples 3 to 6]
The treatment was performed in the same manner as in Example 2 except that the treatment temperature, treatment time, and treatment pressure were changed as described in Table 1.
The reflection spectrum of the silicon nitride is shown in FIG. 4, and the X-ray diffraction pattern is shown in FIG. Table 1 shows the reflectance obtained from the above, the results of measuring the carbon content by a high-frequency furnace heating combustion extraction-non-dispersive infrared detection method (Horiba Seisakusho, EMIA520FA type), and visual body color.

[Comparative Examples 1 to 23]
Table 2 shows the results of measuring visual body color, reflectance, and carbon content (measured by high-frequency furnace heating combustion extraction-non-dispersive infrared detection method (manufactured by Horiba, EMIA520FA type)) for various commercially available Si ₃ N ₄ Shown in

  From the above, the reflectance of silicon nitride of the present invention is 89% for the wavelength 455 nm, 90% for the wavelength 525 nm, and 90% for the wavelength of Example 5 having the lowest reflectance among Examples 1 to 6. The reflectance at 650 nm is 91%. Even when compared with Comparative Example 4 having the highest reflectance among the comparative examples, 10% or more at a wavelength of 455 nm, 3% or more at a wavelength of 525 nm, 2% or more at a wavelength of 650 nm, It was confirmed that the reflectance was high.

[Example 7]
BaCO ₃ (manufactured by Hakuho Chemical Co., 98% purity), SiO ₂ (manufactured by Tatsumori Co., 99.99%) so that the charged composition of each raw material of the phosphor is Ba _2.82 Eu _0.18 Si ₉ O ₁₂ N _6. ), Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.99%), Si ₃ N ₄ obtained in Example 3, and BaF ₂ (Wako Pure Chemical Industries, 99.99%) as a flux. Each was weighed.

Raw material powders BaCO ₃ (5.21 g), SiO ₂ (2.52 g) and Eu ₂ O ₃ (0.30 g) were put in a nylon bag, sufficiently stirred and mixed, and then closely packed in an alumina crucible. This was fired as a primary firing in a resistance heating electric furnace equipped with a temperature controller, heated to 1100 ° C. at a heating rate of 5 ° C./min under atmospheric pressure, held at that temperature for 6 hours, and then released to room temperature. Chilled.

Next, as secondary firing, the sample obtained above, Si ₃ N ₄ (1.97 g) subjected to the heat treatment in Example 3, and BaF ₂ (0.1 g) as a flux were used in an alumina mortar. After pulverizing and mixing, and separating particles having a particle size of 250 μm or less by sieving, they are tightly packed in an alumina crucible and placed in a resistance heating tubular electric furnace equipped with a temperature controller. In a mixed air stream of 96% by volume of nitrogen + 4% by volume of hydrogen, the heating rate was 4.8 ° C / min from room temperature to 800 ° C, and 3.0 ° C / min from 800 ° C to 1300 ° C. Heated at a speed, held at that temperature for 8 hours, then allowed to cool to room temperature, and then pulverized on an alumina mortar.

  The obtained fired product was put into 100 ml of 1N hydrochloric acid, stirred for 30 minutes, allowed to stand, and the supernatant was discarded after 2 hours. 100 ml of pure water was added thereto, stirred for 15 minutes, allowed to stand, and after 30 minutes, the supernatant was discarded and washed with water. The washing operation was further performed three times, followed by filtration, and the filtered product was dried at 110 ° C. for 12 hours. About the obtained baked product, an X-ray diffraction pattern is shown in FIG. 7, and an emission spectrum diagram at a wavelength of 455 nm excitation is shown in FIG.

From the X-ray diffraction pattern, it was found that the fired product obtained in Example 7 had a new crystal phase. As a result of X-ray structural analysis of the fired product having the crystal phase, it was found that the composition formula of the inorganic compound constituting the crystal phase was Ba ₃ Si ₆ O ₁₂ N ₂ .
In addition, the emission characteristics were evaluated based on the emission spectrum. The results are shown in Table 3.

[Examples 8 and 9]
As the silicon nitride to be used, instead the Si ₃ N ₄ obtained in Example 3, Si ₃ N ₄ were obtained in each Example 5, except for using the Si ₃ N ₄ obtained in Example 6 A phosphor was manufactured in the same manner as in Example 7, and X-ray diffraction measurement and emission spectrum measurement were performed. FIG. 7 shows an X-ray diffraction pattern, and FIG. 8 shows an emission spectrum at a wavelength of 455 nm. In addition, the emission characteristics were evaluated based on the emission spectrum. The results are shown in Table 3.

[Comparative Examples 24-31]
As the silicon nitride to be used, in place of the Si ₃ N ₄ obtained in Example 3, each of the examples except that various types of Si ₃ N ₄ having different crystal phase types and impurity carbon amounts shown in Table 3 were used. The phosphor was manufactured in the same manner as in Example 7, and X-ray diffraction measurement and emission spectrum measurement were performed. The reflection spectrum diagram of the raw material silicon nitride is shown in FIG. Further, with respect to the obtained fired product, an X-ray diffraction pattern is shown in FIG. 7, an emission spectrum at a wavelength of 455 nm excitation is shown in FIG.

  From the X-ray diffraction pattern, it can be seen that Comparative Examples 24-31 also have the same crystal phase as the phosphors of Examples 7-9. On the other hand, the object color is duller than that of the example, and the light emission efficiency is lower than that of Example 8, such as the peak height and the external quantum efficiency are low.

[Example 10]
BaCO ₃ (Shirakaba Chemical Co., purity 98%), SrCO ₃ (Shirakaba Chemical Co., purity) so that the raw material composition of each phosphor is Sr _0.7 Ba _0.25 Eu _0.05 Si ₂ O ₂ N ₂ 98%), SiO ₂ (manufactured by Tatsumori, 99.99%), Si ₃ N ₄ obtained in Example 3, Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.99%), NH ₄ Cl (Rare Metallic) was weighed.

Raw powder BaCO ₃ (2.58 g), SrCO ₃ (5.38 g), SiO ₂ (1.59 g) and Eu ₂ O ₃ (0.48 g) are put in an agate automatic mortar, ethanol is added, and wet mixing method Until uniform. The pasty mixture thus obtained was dried and then closely packed in alumina crucibles. This was fired as a primary firing in a resistance heating electric furnace equipped with a temperature controller, heated to 1200 ° C. at a heating rate of 5 ° C./min under atmospheric pressure, held at that temperature for 3 hours, and then released to room temperature. Chilled.

Next, as secondary firing, the sample obtained above, Si ₃ N ₄ (3.66 g) subjected to the heat treatment in Example 3, and NH ₄ Cl (0.08 g) as a flux were used in an alumina mortar. After pulverizing and mixing, particles having a particle size of 250 μm or less were collected by sieving, and this was tightly packed in an alumina crucible and placed in a resistance heating tubular electric furnace with a temperature controller. In a mixed gas stream of 96% by volume of nitrogen + 4% by volume of hydrogen per minute, the heating rate was 4.8 ° C / min from room temperature to 800 ° C, and 3.0 ° C / min from 800 ° C to 1430 ° C. It heated at the temperature increase rate, hold | maintained at the temperature for 8 hours, then, after standing_to_cool to room temperature, the grinding | pulverization process was performed on the alumina mortar. About the obtained baked product, an X-ray diffraction pattern is shown in FIG. 9, and an emission spectrum diagram at a wavelength of 455 nm excitation is shown in FIG.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 4.

[Comparative Example 32]
As Si ₃ N _4, except for using the Si ₃ N ₄ of Comparative Example 23, produce phosphor in the same manner as in Example 10, was subjected to X-ray diffraction measurement and emission spectrum measurement. FIG. 9 shows an X-ray diffraction pattern, FIG. 10 shows an emission spectrum at a wavelength of 455 nm excitation, and Table 4 shows emission characteristics.

  From the X-ray diffraction pattern, it can be seen that Comparative Example 32 also has the same crystal phase as the phosphor of Example 10. On the other hand, the object color is duller than that of the example, and the light emission efficiency is lower than that of Example 10 such as the peak height and the external quantum efficiency are low.

[Example 21]
Mixing composition of the raw materials of the phosphor _were weighed so as to _{Sr 0.5525 Ba 0.2975 Eu 0.15 Si 2} O 2 N 2. That is, SrCO ₃ (24.45 g) BaCO ₃ (17.60 g), SiO ₂ (9.00 g) and Eu ₂ O ₃ (7.91 g) are put into an agate automatic mortar as a phosphor raw material, and ethanol is added. The mixture was mixed by a wet mixing method until uniform. The pasty mixture thus obtained was dried and then closely packed in alumina crucibles. This was placed in a resistance heating type tubular electric furnace equipped with a temperature controller, and under atmospheric pressure, in a mixed air stream of 96 volume% nitrogen + 4 volume% hydrogen at 0.5 l / min, from room temperature to 800 ° C., 4. Heating was performed at a temperature rising rate of 8 ° C./min, from 800 ° C. to 1200 ° C. at a temperature rising rate of 3.0 ° C./min, and kept at that temperature for 6 hours, and then allowed to cool to room temperature. The obtained sample was pulverized in an alumina mortar.

Next, as the secondary firing, the sample obtained by the primary firing (6.927 g), Si ₃ N ₄ (3.07 g) of Example 3 and NH ₄ Cl (0.10 g) were put in an automatic agate mortar. Then, ethanol was added and mixed until uniform by a wet mixing method. The pasty mixture thus obtained was dried and then closely packed in alumina crucibles. This was placed in a resistance heating electric furnace with a temperature controller, and this was allowed to flow from room temperature to 800 ° C. in a mixed gas stream in an atmosphere of 96% by volume of nitrogen and 4% by volume of hydrogen under atmospheric pressure at 0.5 l / min. Heating was performed at a temperature rising rate of 5.0 ° C./min, and from 800 ° C. to 1500 ° C. at a temperature rising rate of 4.0 ° C./min, and kept at that temperature for 6 hours, and then allowed to cool to room temperature. The obtained fired product was pulverized in an alumina mortar. FIG. 14 shows an emission spectrum diagram of the obtained fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 8.

[Comparative Examples 40 and 41]
Except for changing the _Si 3 _{N 4} of Example 21 to _Si 3 _{N 4} of Comparative Example 15 and 23 in Table 2 in the same manner as in Example 21, mixed and fired. The obtained fired product was pulverized in an alumina mortar. FIG. 14 shows an emission spectrum diagram of the obtained fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 8.

  From the above results, it can be seen that the phosphor of Example 21 has a clear object color and higher emission efficiency, such as higher peak height and quantum efficiency, as compared with Comparative Examples 40 and 41.

[Example 22]
Except for changing NH ₄ Cl (0.10 g) in Example 21 to ZnF ₂ .4H ₂ O (0.10 g), mixing and firing were performed in the same manner as in Example 21 to evaluate light emission characteristics and the like. It was.
FIG. 15 shows an emission spectrum at a wavelength of 455 nm excitation, and Table 9 shows the emission characteristics.

From the above results, it can be seen that the same level of performance can be obtained even if the type of flux is changed from NH ₄ Cl to ZnF ₂ .4H ₂ O.

[Examples 23 to 25]
Mixing and firing were performed in the same manner as in Example 21 except that the weighing value of each phosphor material was changed so that the charged composition of the phosphor material was as shown in Table 10, and the light emission characteristics and the like were evaluated. went.
FIG. 16 shows an emission spectrum at a wavelength of 455 nm excitation, and Table 10 shows the emission characteristics.

[Example 11]
Ca ₃ N ₂ (CERAC, purity 99%), AlN (Tokuyama, purity 99%), Eu ₂ O ₃ (Shin-Etsu) so that each raw material charged composition of the phosphor is Ca _0.992 Eu _0.008 AlSiN _3. Chemical Co., Ltd., purity 99.99%), and Si ₃ N ₄ obtained in Example 3 were weighed.

Agate mortar in a glove box filled with raw material powder Ca ₃ N ₂ (0.72 g), Si ₃ N ₄ (0.68 g), AlN (0.60 g), Eu ₂ O ₃ (0.02 g) with nitrogen gas And mixed until uniform by a dry mixing method. The resulting mixture was tightly packed in a boron nitride crucible. This boron nitride crucible was placed in a resistance heating type vacuum pressure atmosphere heat treatment furnace (manufactured by Fuji Denpa Kogyo Co., Ltd.) and vacuumed from room temperature to 800 ° C. under a reduced pressure of <5 × 10 ⁻³ Pa at a heating rate of 20 ° C./min. Heated. When the temperature reached 800 ° C., the temperature was maintained and high-purity nitrogen gas (99.9995%) was introduced for 30 minutes until the pressure became 0.92 MPa, and then the temperature was further increased while maintaining 0.92 MPa. The temperature was raised to 1200 ° C. at a rate of 20 ° C./min. The temperature was maintained for 5 minutes, the thermocouple was changed to a radiation thermometer, and further heated to 1600 ° C. at a rate of temperature increase of 20 ° C./min. When the temperature reached 1600 ° C., the temperature was maintained for 2 hours. Furthermore, it heated to 1800 degreeC with the temperature increase rate of 20 degree-C / min, and when it reached 1800 degreeC, it hold | maintained for 2 hours. Thereafter, it was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, then allowed to cool, and pulverized on an alumina mortar. Table 5 shows the results of evaluation of light emission characteristics based on the emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.

[Comparative Example 33]
A phosphor was manufactured in the same manner as in Example 11 except that the silicon nitride of Comparative Example 23 was used as Si ₃ N ₄ . Table 5 shows the results of evaluation of light emission characteristics based on the emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.

[Example 12]
Ca ₃ N ₂ (manufactured by CERAC, purity 99%), Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical, purity 99.99%) so that each raw material charged composition of the phosphor is Ca _1.98 Eu _0.02 Si ₅ N _8. ), Si ₃ N ₄ obtained in Example 3 was weighed.

Raw material powder Ca ₃ N ₂ (0.59 g), Si ₃ N ₄ (1.40 g), Eu ₂ O ₃ (0.02 g) is put in an agate mortar in a glove box filled with nitrogen gas, and dried by a dry mixing method. Mix until uniform. The resulting mixture was tightly packed in a boron nitride crucible. This boron nitride crucible was placed in a resistance heating type vacuum pressure atmosphere heat treatment furnace (manufactured by Fuji Denpa Kogyo Co., Ltd.) and vacuumed from room temperature to 800 ° C. under a reduced pressure of <5 × 10 ⁻³ Pa at a heating rate of 20 ° C./min. Heated. When the temperature reached 800 ° C., the temperature was maintained and high-purity nitrogen gas (99.9995%) was introduced for 30 minutes until the pressure became 0.92 MPa, and then the temperature was further increased while maintaining 0.92 MPa. The temperature was raised to 1200 ° C. at a rate of 20 ° C./min. The temperature was maintained for 5 minutes, the thermocouple was changed to a radiation thermometer, and further heated to 1600 ° C. at a rate of temperature increase of 20 ° C./min. When the temperature reached 1600 ° C., the temperature was maintained for 2 hours. Furthermore, it heated to 1800 degreeC with the temperature increase rate of 20 degree-C / min, and when it reached 1800 degreeC, it hold | maintained for 2 hours. Thereafter, it was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, then allowed to cool, and pulverized on an alumina mortar. Table 5 shows the results of evaluation of light emission characteristics based on the emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.

[Comparative Example 34]
A phosphor was manufactured in the same manner as in Example 12 except that the silicon nitride of Comparative Example 23 was used as Si ₃ N ₄ . Table 5 shows the results of evaluation of light emission characteristics based on the emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.

[Example 26]
SrNH (1.38 g) as the phosphor material and Si ₃ N _{4 of} Example 3 (1.1) so that the charging composition of each material of the phosphor is Sr _1.98 Eu _0.02 Si ₅ N ₈ . 59 g) and Eu ₂ O ₃ (0.02 g) were weighed in a glove box filled with nitrogen and mixed until uniform in an alumina mortar. The mixed powder thus obtained was closely packed in a boron nitride crucible. This was heated to 1400 ° C. in a nitrogen atmosphere under a pressure of 0.92 MPa, kept at that temperature for 4 hours, and then allowed to cool. The obtained sample was pulverized on an alumina mortar, heated again to 1600 ° C. in a nitrogen atmosphere under a pressure of 0.92 MPa, kept at that temperature for 4 hours, and then allowed to cool. The obtained fired product was pulverized in an alumina mortar. FIG. 17 shows an emission spectrum of the fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 11.

[Comparative Examples 42 and 43]
Except for changing the _Si 3 _{N 4} of Example 26 to _Si 3 _{N 4} of Comparative Example 15 and 23 in Table 2 in the same manner as in Example 26, mixed and fired. The obtained fired product was pulverized in an alumina mortar. FIG. 17 shows an emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 11.

[Example 27]
BaNH (1.60 g) as the phosphor material and Si ₃ N _{4 of} Example 3 (1.1) so that the charging composition of each material of the phosphor becomes Ba _1.98 Eu _0.02 Si ₅ N ₈ . 37 g) and Eu ₂ O ₃ (0.02 g) were weighed in a glove box filled with nitrogen and mixed on an alumina mortar until uniform. The mixed powder thus obtained was fired by the same operation as in Example 26. The obtained fired product was pulverized in an alumina mortar. The obtained fired product was pulverized in an alumina mortar. FIG. 18 shows an emission spectrum of the fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 12.

[Comparative Example 44]
Except for changing the _Si 3 _{N 4} of Example 27 to _Si 3 _{N 4} of Comparative Example 23 of Table 2 in the same manner as in Example 27, mixed and fired. The obtained fired product was pulverized in an alumina mortar. FIG. 18 shows an emission spectrum of the obtained fired product with excitation at a wavelength of 455 nm.
In addition, the emission characteristics were evaluated based on the emission spectrum. The emission characteristics are shown in Table 12.

[Example 13]
BaCO ₃ (manufactured by Hakuho Chemical Co., 98% purity), SiO ₂ (manufactured by Tatsumori Co., 99.99%) so that the charged composition of each raw material of the phosphor is Ba _2.82 Eu _0.18 Si ₉ O ₁₂ N _6. ), Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd., purity 99.99%), Si ₃ N ₄ obtained in Example 3, and ZnF ₂ .4H ₂ O as a flux (manufactured by Wako Pure Chemical Industries, Ltd. 99. 99%) was weighed.

Raw material powder BaCO ₃ (10.83 g), SiO ₂ (5.16 g), Eu ₂ O ₃ (0.60 g), Si ₃ N ₄ (4.02 g) heat-treated in Example 3, and flux A certain ZnF ₂ .4H ₂ O (0.31 g: 1.5% by weight with respect to the raw material mixture) was put into an agate automatic mortar, ethanol was added, and the mixture was mixed until uniform by a wet mixing method. The pasty mixture thus obtained was dried and then closely packed in alumina crucibles. As a primary firing, this was placed in a resistance heating type tubular electric furnace with a temperature controller, and at room temperature to 800 ° C. in a mixed air stream of 96 volume% nitrogen + 4 volume% hydrogen at 0.5 l / min under atmospheric pressure. Was heated at a rate of temperature increase of 4.8 ° C./min, from 800 ° C. to 1200 ° C. at a rate of temperature increase of 3.0 ° C./min, held at that temperature for 4 hours, and then allowed to cool to room temperature.

  Next, as a secondary firing, the sample obtained above is pulverized and mixed in an alumina mortar, and particles having a particle size of 50 μm or less are collected by sieving, then closely packed in an alumina crucible, and heated with a temperature controller. The temperature rising rate is 4.8 ° C./min from room temperature to 800 ° C. in a mixed air flow of 96 volume% nitrogen + 4 volume% hydrogen under atmospheric pressure at 0.5 l / min. From 800 ° C. to 1300 ° C., heated at a rate of temperature increase of 3.0 ° C./min, held at that temperature for 4 hours, then allowed to cool to room temperature, pulverized in an alumina mortar, and sieved to 50 μm. Particles having the following particle sizes were collected.

  The obtained fired product was put into 100 ml of 1N hydrochloric acid, stirred for 30 minutes, allowed to stand, and the supernatant was discarded after 2 hours. 100 ml of pure water was added thereto, stirred for 15 minutes, allowed to stand, and after 30 minutes, the supernatant was discarded and washed with water. The washing operation was further performed three times, followed by filtration, and the filtered product was dried at 110 ° C. for 12 hours. About the obtained baked product, an X-ray diffraction pattern is shown in FIG. 11, and an emission spectrum diagram at a wavelength of 455 nm excitation is shown in FIG.

  From the X-ray diffraction pattern, it was confirmed that the fired product obtained in Example 13 had the same crystal phase as in Example 7. In addition, the emission characteristics were evaluated based on the emission spectrum. The results are shown in Table 7.

[Examples 14 to 20]
Each phosphor was manufactured in the same manner as in Example 13 except that the charged molar composition ratio of the raw materials was changed as shown in Table 6. The X-ray diffraction pattern of the obtained fired product is shown in FIG. 11, and the emission spectrum at a wavelength of 455 nm excitation was measured. FIG. 13 shows the measured emission spectrum for Examples 14, 15, 17, and 19. In addition, Table 7 shows the results of evaluating the light emission characteristics based on the emission spectrum.

[Comparative Examples 35-39]
As the raw material silicon nitride, instead of Si ₃ N ₄ subjected to the heat treatment in Example 3, the silicon nitride of Comparative Example 4 was used, but the same as in Examples 13, 14, 16, 18 and 20. Thus, a phosphor was manufactured. FIG. 12 shows the X-ray diffraction pattern of the fired product obtained, and Table 7 shows the results of evaluation of the light emission characteristics based on the emission spectrum with excitation at a wavelength of 455 nm.

  From the above results, the phosphor of the present invention has higher relative peak intensity and relative luminance and higher luminous efficiency than the phosphor of the comparative example, and the firing temperature is particularly low at 1600 ° C. or lower, particularly 1500 ° C. or lower. It turns out that the effect is remarkable about the fluorescent substance baked at temperature.

[Example 28]
A boron nitride crucible was charged with 250 g of α-Si ₃ N ₄ (Ube Industries' SN-E10), and this boron nitride crucible was placed in a resistance heating type vacuum heat treatment furnace (manufactured by Fuji Denpa Kogyo). Under reduced pressure of 5 × 10 ⁻³ Pa, vacuum heating was performed from room temperature to 800 ° C. at a heating rate of 20 ° C./min. When the temperature reached 800 ° C., the temperature was maintained and high-purity nitrogen gas (99.9995%) was introduced for 30 minutes until the pressure became 0.92 MPa, and then the temperature was further increased while maintaining 0.92 MPa. The temperature was raised to 1200 ° C. at a rate of 20 ° C./min. The temperature was maintained for 5 minutes, the thermocouple was changed to a radiation thermometer, and when the temperature was further increased to 1800 ° C. at a temperature increase rate of 20 ° C./min, the temperature was increased to 2000 ° C. at a temperature increase rate of 10 ° C./min. When it reached 2000 ° C., it was held for 5 hours. Thereafter, it was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, then allowed to cool, and subjected to a sieving treatment to collect particles having a particle size of 250 μm or less.

Table 13 shows the characteristics of the obtained β-Si ₃ N ₄ . The specific surface area of silicon nitride was measured by a continuous flow BET one-point method using a fully automatic specific surface area measuring device (flow method) manufactured by Okura Riken Co., Ltd. model: AMS1000A. Further, FIG. 19 shows a drawing-substituting photograph in which the obtained β-Si ₃ N ₄ is photographed with a scanning electron microscope.

A phosphor was manufactured using the β-Si ₃ N ₄ obtained above. That is, BaCO ₃ (293 g), SiO ₂ (149 g), and Eu ₂ O ₃ (29 g) were used as the phosphor raw materials so that the charged composition of each raw material of the phosphor was Ba _2.7 Eu _0.3 Si _6.9 O ₁₂ N _3.2. After sufficiently stirring and mixing, the mixture was filled in an alumina crucible. This is placed in a resistance heating electric furnace with a temperature controller, heated to 1100 ° C. at a heating rate of 4 ° C./min in an atmospheric atmosphere at atmospheric pressure, held at that temperature for 6 hours, and then allowed to cool to room temperature. did. The obtained sample was pulverized to 100 μm or less on an alumina mortar.

After sufficiently stirring and mixing the sample (177 g) obtained above and β-Si ₃ N ₄ (34 g), the alumina crucible was filled as primary firing, and this was 96% by volume of nitrogen under atmospheric pressure. The mixture was heated to 1170 ° C. under a flow of 3 l / min of a mixed gas of 4% by volume of hydrogen, kept at that temperature for 6 hours, and then allowed to cool to room temperature. The obtained fired powder was pulverized on an alumina mortar until it became 100 μm or less.

After sufficiently stirring and mixing 200 g of the calcined powder obtained by the primary firing, BaF ₂ (3 g), which is a flux, and BaHPO ₄ (6 g), the alumina crucible with molybdenum lining is filled into the secondary crucible. As calcination, the mixture was heated to 1320 ° C. under a flow of 3 l / min of a mixed gas of 96 volume% nitrogen + 4 volume% hydrogen at atmospheric pressure, kept at that temperature for 20 hours, and then allowed to cool to room temperature. The obtained fired powder was pulverized on an alumina mortar until it became 100 μm or less.

The sample obtained by the secondary firing (200 g), the flux BaF ₂ (4 g), BaCl ₂ (20 g), and BaHPO ₄ (10 g) were sufficiently stirred and mixed, and then put into an alumina crucible. Filled and heated to 1170 ° C. under a flow of 3 l / min of mixed gas of 96% by volume of nitrogen and 4% by volume of hydrogen at the atmospheric pressure as the third firing, held at that temperature for 6 hours, and then allowed to cool to room temperature . The obtained calcined powder was slurried using glass beads and dispersed, and 60 μm or less was collected with a sieve, washed with 1N hydrochloric acid, dehydrated and dried, and 60 μm or less was sieved.
Table 14 shows the characteristics of the obtained phosphor.

[Example 29]
A boron nitride crucible was charged with 250 g of α-Si ₃ N ₄ (Ube Industries' SN-E10), and this boron nitride crucible was placed in a resistance heating type vacuum heat treatment furnace (manufactured by Fuji Denpa Kogyo). Under reduced pressure of 5 × 10 ⁻³ Pa, vacuum heating was performed from room temperature to 800 ° C. at a heating rate of 20 ° C./min. When the temperature reached 800 ° C., high-purity nitrogen gas (99.9995%) was introduced for 30 minutes so that the temperature was maintained and the pressure became 0.92 MPa. The heating was stopped and the mixture was allowed to cool naturally. Thereafter, the silicon nitride was again heat-treated by the same procedure as in Example 28 to obtain β-Si ₃ N ₄ . Table 13 shows the characteristics of the obtained β-Si ₃ N ₄ . Further, FIG. 20 shows a drawing-substituting photograph obtained by photographing the obtained β-Si ₃ N ₄ with a scanning electron microscope.

A phosphor was manufactured using β-Si ₃ N ₄ obtained as described above. That is, a phosphor was obtained by the same procedure as in Example 28 except that β-Si ₃ N ₄ obtained above was used.
Table 14 shows the characteristics of the obtained phosphor.

From the above results, it can be seen that the use of β-Si ₃ N ₄ having a small specific surface area tends to provide a phosphor having high luminance.

Example 30 Production of β-silicon nitride by adding silica
250 g of α-Si ₃ N ₄ (SN-E10 manufactured by Ube Industries) and 15 g of SiO ₂ were sufficiently stirred and mixed. This was heated by the same procedure as in Example 28 except that the temperature rising rate from 1600 ° C. to 2000 ° C. was 5 ° C./min and the 2000 ° C. holding time was 4 hours to obtain β-Si ₃ N ₄ . . Large particles β-silicon nitride having a small specific surface area was obtained by increasing oxygen in the raw material by adding silica. Table 15 shows the characteristics of the obtained β-Si ₃ N ₄ . In addition, FIG. 21 shows a drawing-substituting photograph obtained by photographing the obtained β-Si ₃ N ₄ with a scanning electron microscope.

[Example 31] Production of β-silicon nitride by atmospheric firing 20 g of α-Si ₃ N ₄ (SN-E10 manufactured by Ube Industries) was charged into an alumina crucible. This was placed in a resistance heating electric furnace with a temperature controller, heated to 1150 ° C at a heating rate of 5 ° C / min in an atmospheric atmosphere at atmospheric pressure, held at that temperature for 4 hours, and then allowed to cool to room temperature. did.
This was heated by the same procedure as in Example 28 to obtain β-Si ₃ N ₄ . Large particles β-silicon nitride having a small specific surface area was obtained by increasing the oxygen in the raw material by air firing. Table 15 shows the characteristics of the obtained β-Si ₃ N ₄ . Further, FIG. 22 shows a drawing-substituting photograph obtained by photographing the obtained β-Si ₃ N ₄ with a scanning electron microscope.

  From the above results, it can be seen that the specific surface area of β-silicon nitride obtained is reduced when silicon nitride is treated in the presence of a small amount of oxygen atoms.

[Example 32]
Barium carbonate, silica, and europium oxide were mixed at an atomic ratio of 1.82: 3: 0.18, and baked in the atmosphere at 1100 ° C. for 5 hours to obtain (Ba _0.9 Eu _0.1 ) _2. Si ₃ O ₈ was obtained.

The obtained (Ba _0.9 Eu _0.1 ) ₂ Si ₃ O _{8 was} 0.5 times mole Si ₃ N ₄ (the heat-treated product in the N ₂ atmosphere described above, and the average particle size ( D ₅₀ ) about 5 μm (after ultrasonic dispersion), about 85 μm (before ultrasonic dispersion) and containing 10 ppm by weight of the impurity element Fe) are added and mixed, and 4% H ₂ / N ₂ flow condition (96% by volume of nitrogen) + 4% by volume of hydrogen mixed gas), and fired at 1220 ° C. for 6 hours in an atmosphere firing furnace.

BaF ₂ 2 wt% and BaHPO ₄ 2 wt% were added as flux to the obtained fired product and fired at 1360 ° C. for 9 hours in an atmosphere firing furnace under 4% H ₂ / N ₂ flow conditions. BaCl ₂ 8% by weight, BaHPO ₄ 5% by weight and BaF ₂ 1% by weight were added to the fired product, and the resulting fired product was treated at 1220 ° C. for 6 hours in an atmosphere firing furnace under 4% H ₂ / N ₂ flow conditions. The obtained fired product was crushed, crushed with a wet ball mill using water as a dispersion medium, and washed with dilute hydrochloric acid. Thereafter, crushing, classification, washing with water and drying were further performed to obtain a phosphor having an average particle size (D ₅₀ ) of about 20 μm. Table 16 shows the results of evaluating the emission characteristics, quantum efficiency, and object color at 455 nm excitation.

[Example 33]
As the raw material Si ₃ N ₄ , one obtained by pulverizing Si ₃ N ₄ used in Example 32 in the atmosphere with a jet mill was used. That is, barium carbonate, silica, and europium oxide were mixed at an atomic ratio of 1.82: 3: 0.18, and baked in the atmosphere at 1100 ° C. for 5 hours to obtain (Ba _0.9 Eu _0.1 ) ₂ Si ₃ O ₈ was obtained.

0.5 times moles of Si ₃ N ₄ (average particle diameter (D ₅₀ ) of about 2 μm (after ultrasonic dispersion), about 5 μm with respect to the obtained (Ba _0.9 Eu _0.1 ) ₂ Si ₃ O ₈ (Before ultrasonic dispersion), 147 ppm by weight of impurity element Fe) was added and mixed, and the atmosphere firing furnace under 4% H ₂ / N ₂ flow conditions (mixed air flow of 96 volume% nitrogen + 4 volume% hydrogen) And calcined at 1220 ° C. for 6 hours.

BaF ₂ 2 wt% and BaHPO ₄ 2 wt% were added as flux to the obtained fired product and fired at 1290 ° C. for 10 hours in an atmosphere firing furnace under 4% H ₂ / N ₂ flow conditions. The obtained fired product was crushed to obtain a phosphor having an average particle diameter (D ₅₀ ) of about 20 μm. Table 16 shows the results of evaluating the emission characteristics, quantum efficiency, and object color at 455 nm excitation.

[Example 34]
As a raw material _Si 3 _{N 4,} washing the _Si 3 _{N 4} was used further with 2N hydrochloric acid in embodiment 33, water washing, dehydrating, drying, those obtained performed sieve (average particle size _{(D 50)} of about 2 [mu] m (ultrasonic dispersion After), a phosphor was obtained in the same manner as in Example 33 except that about 3 μm (before ultrasonic dispersion) and 13 wt ppm of the impurity element Fe were used. The obtained fired product was crushed to obtain a phosphor having an average particle size (D ₅₀ ) of about 22 μm. Table 16 shows the results of evaluating the emission characteristics, quantum efficiency, and object color at 455 nm excitation.

  From the above results, when using raw material silicon nitride with a high Fe content by jet mill treatment, the body color of the phosphor becomes unclear, but by further acid cleaning and reducing the Fe content, It can be seen that a phosphor having an excellent body color can be obtained again. On the other hand, it can be seen from the comparison of emission intensity and the like that it is desirable to change the firing conditions in accordance with the change in the particle size of the raw material silicon nitride.

  The present invention relates to silicon nitride useful as a raw material for inorganic materials, and can be used in any industrial field. In particular, it is useful in the fields of phosphors, ceramics, pigments, and the like, and the phosphors are particularly suitable for applications using light such as illumination and image display devices.

In addition, the phosphor of the present invention can be used in any industrial field, for example, in a light emitting device. Among them, the phosphor of the present invention is suitable for use in a white light-emitting device because the decrease in light emission efficiency accompanying a temperature rise is usually smaller than that of a YAG: Ce phosphor that has been widely used in white light-emitting devices. is there.
Furthermore, since the phosphor of the present invention usually has acid stability and high temperature stability, it is useful as a heat resistant material.

  The phosphor, the phosphor-containing composition and the light-emitting device of the present invention are widely used and can be used in the field of image display devices such as lighting or displays. Among them, the LED for general illumination is particularly suitable for the purpose of realizing a high-power lamp, particularly a white LED for backlight having a high luminance and a wide color reproduction range.

It is a typical perspective view which shows the positional relationship of an excitation light source (1st light emission body) and a fluorescent substance containing part (2nd light emission body) in an example of the light-emitting device of this invention. 2 (a) and 2 (b) are schematic cross sections showing an embodiment of a light emitting device having an excitation light source (first light emitter) and a phosphor-containing portion (second light emitter). FIG. It is sectional drawing which shows typically one Embodiment of the illuminating device of this invention. It is a reflection spectrum figure of silicon nitride obtained in Examples 1-6 of the present invention. It is a figure showing the X-ray-diffraction pattern of the silicon nitride obtained in Examples 1-6 of this invention. It is a reflection spectrum figure of raw material silicon nitride used by comparative examples 24-31. It is a figure showing the X-ray-diffraction pattern of the fluorescent substance obtained in Examples 7-9 and Comparative Examples 24-31 of this invention. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Examples 7-9 and Comparative Examples 24-31 of this invention with the light of wavelength 455nm. It is a figure showing the X-ray-diffraction pattern of the fluorescent substance obtained in Example 10 and Comparative Example 32 of this invention. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 10 and Comparative Example 32 of this invention with the light of wavelength 455nm. It is a figure showing the X-ray-diffraction pattern of the fluorescent substance obtained in Examples 13-20 of this invention. It is a figure showing the X-ray-diffraction pattern of the fluorescent substance obtained by Comparative Examples 35-39 of this invention. It is an emission spectrum figure at the time of exciting the phosphor obtained in Examples 13-15, 17 and 19 of this invention with the light of wavelength 455nm. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 21 and Comparative Examples 40-41 of this invention with the light of wavelength 455nm. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 21 and 22 of this invention with the light of wavelength 455nm. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 21, 23-25 of this invention with the light of wavelength 455nm. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 26 of this invention and Comparative Examples 42-43 with the light of wavelength 455nm. It is an emission spectrum figure at the time of exciting the fluorescent substance obtained in Example 27 and Comparative Example 44 of this invention with the light of wavelength 455nm. It is a drawing substitute photograph which image | photographed the silicon nitride obtained in Example 28 of this invention with the scanning electron microscope. It is a drawing substitute photograph which image | photographed the silicon nitride obtained in Example 29 of this invention with the scanning electron microscope. It is a drawing substitute photograph which image | photographed the silicon nitride obtained in Example 30 of this invention with the scanning electron microscope. It is a drawing substitute photograph which image | photographed the silicon nitride obtained in Example 31 of this invention with the scanning electron microscope.

Explanation of symbols

1: Second light emitter 2: Surface-emitting GaN-based LD
3: Substrate 4: Light-emitting device 5: Mount lead 6: Inner lead 7: First light-emitting body 8: Phosphor-containing resin part 9: Conductive wire 10: Mold member 11: Surface-emitting illumination device 12: Holding case 13: Light emitting device 14: Diffuser 22: First light emitter 23: Second light emitter 24: Frame 25: Conductive wire 26, 27: Electrode

Claims (23)

Crystalline silicon nitride having a crystalline phase and having a reflectance of 85% or more when irradiated with light having a wavelength of 525 nm. The crystalline silicon nitride according to claim 1, wherein the amount of impurity carbon is 0.06 wt% or less. The crystalline silicon nitride according to claim 1, wherein the crystalline phase is β-type. A method for producing crystalline silicon nitride, comprising heat-treating silicon nitride at a temperature of 1500 ° C. or higher in an atmosphere containing nitrogen gas having an N ₂ partial pressure of 0.4 MPa or higher. The method for producing crystalline silicon nitride according to claim 4, wherein the silicon nitride is heat-treated in advance at a temperature of 800 to 1300 ° C in an oxygen gas-containing atmosphere having an O ₂ partial pressure of 0.01 MPa or more. The method for producing crystalline silicon nitride according to claim 4, wherein the heat treatment is performed in the presence of SiO ₂ . 4. A phosphor using the crystalline silicon nitride according to claim 1 as a raw material. The phosphor according to claim 6, wherein the phosphor is selected from the group consisting of nitridosilicate, nitridoaluminosilicate, oxonitridosilicate, oxonitridoaluminosilicate, and carbonitridealuminosilicate. The phosphor according to claim 7 or 8, wherein the phosphor is represented by the following formula [I] or [II].
^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
(In the formula [I],
M ¹ represents at least one activator selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb,
M ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn,
L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the Periodic Table, and at least a part of L is an Si element;
x, y, z, u, v, and w each represent a numerical value in the following range.
0.00001 ≦ x ≦ 3
0 ≦ y ≦ 2.99999
2.6 ≦ x + y + z ≦ 3
0 <u ≦ 11
6 <v ≦ 25
0 <w ≦ 17)
M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
(In the formula [II],
M ³ represents an activator element,
e represents a positive number satisfying 0 <e ≦ 0.2. ) When the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value is 97 or more, the a ^* value is −21 or less, and the b ^* value is 35 or more,
A phosphor represented by the following formula [I].
^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
(In the formula [I],
M ¹ represents at least one activator selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb,
M ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn,
L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the Periodic Table, and at least a part of L is an Si element;
x, y, z, u, v, and w each represent a numerical value in the following range.
0.00001 ≦ x ≦ 3
0 ≦ y ≦ 2.99999
2.6 ≦ x + y + z ≦ 3
0 <u ≦ 11
6 <v ≦ 25
0 <w ≦ 17) The external quantum efficiency is 0.35 or more,
A phosphor represented by the following formula [I].
^{_{M 1 x Ba y M 2 z}} L u O v N w [I]
(In the formula [I],
M ¹ represents at least one activator selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb,
M ² represents at least one divalent metal element selected from Sr, Ca, Mg and Zn,
L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the Periodic Table, and at least a part of L is an Si element;
x, y, z, u, v, and w each represent a numerical value in the following range.
0.00001 ≦ x ≦ 3
0 ≦ y ≦ 2.99999
2.6 ≦ x + y + z ≦ 3
0 <u ≦ 11
6 <v ≦ 25
0 <w ≦ 17) When the object color is expressed in the L ^* a ^* b ^* color system, the L ^* value satisfies 103 or more, the a ^* value is −23 or less, and the b ^* value is 63 or more,
A phosphor represented by the following formula [II].
M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
(In the formula [II],
M ³ represents an activator element,
e represents a positive number satisfying 0 <e ≦ 0.2. ) The emission peak wavelength is 550 nm to 570 nm, the L ^* value is 100 or more and the b ^* value is 77 or more.
The phosphor according to claim 12, represented by the following formula [II '].
M ³ _e (Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II ′]
(In the formula [II ′],
M ³ represents an activator element,
e represents a positive number satisfying 0 <e ≦ 0.2. ) The external quantum efficiency is 0.57 or more,
A phosphor represented by the following formula [II].
M ³ _e (Ca, Sr, Ba) _1-e Si ₂ O ₂ N ₂ [II]
(In the formula [II],
M ³ represents an activator element,
e represents a positive number satisfying 0 <e ≦ 0.2. ) A phosphor represented by the following formula [I ′].
M ¹ _χ (Ba, Ln) _a (L, Al) _b O _c N _d [I ′]
(In the formula [I ′],
M ¹ represents at least one activator selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb,
Ln represents La, Ce, Pr, Nd, Y and Gd;
L is a metal element selected from metal elements belonging to Group 4 or Group 14 of the Periodic Table, and at least a part of L is an Si element;
χ, a, b, c, and d represent numerical values in the following ranges, respectively.
0.00001 ≦ χ ≦ 0.4
2.6 ≦ a ≦ 2.99999
5 ≦ b ≦ 7
11 <c <13
0 <d <2.4) The phosphor according to claim 15, which is a solid solution of the phosphor represented by the formula [I] according to any one of claims 9 to 11 and langasite. A phosphor-containing composition comprising the phosphor according to any one of claims 7 to 16 and a liquid medium. A first light emitter, and a second light emitter that emits visible light when irradiated with light from the first light emitter,
The light emitting device, wherein the second light emitter contains one or more kinds of the phosphors according to any one of claims 7 to 16 as a first phosphor. 19. The light emitting device according to claim 18, wherein the second phosphor includes at least one phosphor having a different emission peak wavelength from the first phosphor as the second phosphor. . An illumination device comprising the light-emitting device according to claim 18. An image display device comprising the light-emitting device according to claim 18. A sintered body obtained by sintering the crystalline silicon nitride according to any one of claims 1 to 3. A pigment comprising the crystalline silicon nitride according to claim 1.