JP2009057554A - Method for producing fluorescent material, fluorescent material obtained by the same, fluorescent material-containing composition using the fluorescent material, light emitting device, lighting device and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: an alkali metal element- and/or alkaline earth metal element-containing nitride fluorescent material having high light-emitting intensity in comparison with a conventional one; a composition containing the fluorescent material; a light-emitting device using the composition; an image display device; and a lighting device. <P>SOLUTION: A method for producing the fluorescent material comprises firing a raw material mixture for the fluorescent material containing compounds selected from the group comprising an alkali metal imide, an alkali metal amide, an alkaline earth metal imide, and an alkaline earth metal amide. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a phosphor manufacturing method, a phosphor obtained by the manufacturing method, and a phosphor-containing composition, a light emitting device, an illumination device, and an image display device using the phosphor.

In recent years, nitrides and oxynitride phosphors containing Si have attracted attention as phosphors for image display devices and illumination devices that use blue light-emitting diodes (hereinafter referred to as “LEDs” as appropriate) or near-ultraviolet LEDs as excitation light sources. Has been. As such a phosphor, for example, various phosphors such as a phosphor having a host crystal structure represented by (Sr, Ba) ₂ Si ₅ N ₈ (hereinafter referred to as “258 phosphor” as appropriate). Has been developed.

  As a method for producing the phosphor, Non-Patent Document 1 discloses a method using an alkaline earth metal carbonate as a raw material. Regarding this method, Non-Patent Document 1 discloses that the raw material is treated in the atmosphere compared to a conventionally known method using an alkaline earth metal itself, a method using a metal nitride as a raw material, or a method using an alkaline earth oxide. It is described that it is a preferable method that is simple and highly versatile in that it can be handled in the medium, and that the resulting phosphor has excellent luminance.

Chem. Mater. , Vol. 18, 2006, p. 5578-5853

However, as can be seen from Fig. 2, the phosphor obtained by the method described in Non-Patent Document 1 has a peak derived from the impurity phase, has not obtained unity, and is still insufficient from the viewpoint of practical use. It is.
In recent years, from the viewpoint of cost, power consumption, etc., there has been an increasing demand for image display devices and lighting devices with higher luminance and higher light emission efficiency, and phosphors with higher light emission efficiency than conventional ones. The appearance of is desired.

  The present invention has been made in view of the above problems, and provides a method for producing a phosphor having higher emission intensity than the conventional one, a phosphor obtained by the production method, and a phosphor-containing composition containing the phosphor. Another object of the present invention is to provide a light emitting device, an image forming apparatus, and an illuminating device that are more efficient than conventional ones.

  In order to solve the above-mentioned problems, the present inventors have paid attention to phosphor raw materials, and as a result of intensive studies, in alkali phosphors containing alkali metal elements and / or alkaline earth metal elements, alkali metal imides and alkali metals are used as raw materials. By using a compound selected from the group consisting of amides, alkaline earth metal imides and alkaline earth metal amides, it has been found that a phosphor having a higher emission intensity than before can be obtained, and the present invention has been completed.

  That is, the gist of the present invention is characterized by having a step of firing a phosphor raw material mixture containing a compound selected from the group consisting of alkali metal imides, alkali metal amides, alkaline earth metal imides and alkaline earth metal amides. (1).

At this time, the firing is preferably performed in an atmosphere containing N ₂ gas (claim 2).
In addition, it is preferable that the N ₂ gas partial pressure is greater than 0.1 MPa and less than or equal to 200 MPa (Claim 3).
Moreover, it is also preferable to carry out in 0-1 * 10 < ^-4 > m < ³ > / s nitrogen stream (Claim 4).
Further, as the phosphor, (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : R, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : R, (Mg, Ca, Sr, Ba) ₃ Si ₆ O ₁₂ N ₂ : R, (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : R or (Mg, Ca, Sr, Ba) _x (Si, Al) ₁₂ It is preferable to manufacture what is represented by (O, N) ₁₆ : R (R is an activating element, and x is a numerical value satisfying 0 <x <1).

  Another subject matter of the present invention resides in a phosphor obtained by the production method of the present invention (claim 6).

  Still another subject matter of the present invention lies in a phosphor-containing composition comprising the phosphor of the present invention and a liquid medium (claim 7).

  According to still another aspect of the present invention, there is provided 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 present light emitter. The present invention resides in a light-emitting device comprising at least one of the phosphors of the invention as a first phosphor.

  At this time, in the light emitting device of the present invention, it is preferable that the second light emitter contains at least one phosphor having a different emission peak wavelength from the first phosphor as the second phosphor ( Claim 9).

  Still another subject matter of the present invention lies in an illuminating device comprising the light emitting device of the present invention (claim 10).

  Still another subject matter of the present invention lies in an image display device comprising the light emitting device of the present invention (claim 11).

According to the phosphor manufacturing method and the phosphor of the present invention, a phosphor with high emission intensity can be realized.
According to the phosphor-containing composition of the present invention, a phosphor-containing composition containing a phosphor with high emission intensity can be realized.
According to the light emitting device, the image display device, and the lighting device of the present invention, it is possible to realize a light emitting device, an image display device, and a lighting device that are more efficient than conventional ones.

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.
Moreover, in the description regarding the following phosphors, the relationship between color names and chromaticity coordinates are all based on JIS standards (JIS Z8110 and Z8701).

Further, in the phosphor composition formulas 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).

[1. Method for producing phosphor]
The production method of the present invention includes a step of firing a phosphor raw material mixture containing a compound selected from the group consisting of alkali metal imides, alkali metal amides, alkaline earth metal imides, and alkaline earth metal amides. In the following description, this production method may be abbreviated as an imide / amide method.

The phosphor to be manufactured by the imide / amide method is usually a nitride or oxynitride phosphor containing an alkali metal element and / or an alkaline earth metal element. Among them, a phosphor containing an alkali metal element and / or an alkaline earth metal element and at least one element selected from the group consisting of Si, Al, and a lanthanoid element, more preferably an alkaline earth metal element Nitride phosphors or oxynitride phosphors containing silicon, more preferably silicon nitride phosphors or silicate nitride phosphors containing an alkaline earth metal element, particularly preferably (Mg, Ca, Sr). , Ba) ₂ Si ₅ (N, O) ₈ : R, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : R, (Mg, Ca, Sr, Ba) ₃ Si ₆ O ₁₂ N ₂ : R, (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Fluorescence represented by R or (Mg, Ca, Sr, Ba) _x (Si, Al) ₁₂ (O, N) ₁₆ : R Is the body. Here, R represents an activator element, and x represents a numerical value satisfying 0 <x <1.

Specific examples of phosphors to be manufactured by the imide / amide method include Eu-activated α sialon, Eu-activated β sialon, (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Mg, Ca, Sr, Ba) Si ₇ (N, O) ₁₀ : Eu, (Mg, Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Mg, Ca, Sr, Ba) AlSi ( N, O) ₃ : Eu, SrSi ₉ Al ₁₉ ON ₃₁ : Eu, EuSi ₉ Al ₁₉ ON ₃₁ , (Mg, Ca, Sr, Ba) ₃ Si ₆ O ₉ N ₄ : Eu, (Mg, Ca, Sr, Ba) ₃ Si ₆ O ₁₂ N ₂ : Eu-activated nitride or oxynitride phosphor such as Eu, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Ce-activated nitride such as Ce or oxynitride _{phosphor, (Ba, Sr, Ca)} x Si y N z Eu, Ce (provided that, x, y, z are 1 or more represents an integer.) Eu, Ce-activated nitride phosphor such _{as, LaSi 3 N 5: Ce,} La 3 Si 6 N 11: such as Ce Examples thereof include Ce-activated rare earth element-containing silicon nitride phosphors. Among these, a nitride phosphor is preferable, and (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Mg, Ca, Sr, Ba) AlSi (N, O) is more preferable. ₃ ): Eu and (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Ce.

[Imide compound / amide compound]
The imide / amide method is characterized in that an imide compound and / or an amide compound containing one or more elements constituting the phosphor is used as a raw material. In addition, at least a part of the imide compound and / or amide compound used in the imide / amide method includes at least an alkali metal element or an alkaline earth metal element.

  On the other hand, examples of the alkali metal element and alkaline earth metal element contained in the imide compound or amide compound include, for example, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and calcium. (Ca), strontium (Sr), and barium (Ba). Of these, calcium (Ca), strontium (Sr) or barium (Ba) is preferable, and strontium (Sr) or barium (Ba) is more preferable.

  In addition, the imide compound and the amide compound may contain only one kind of the above-described alkali metal element and alkaline earth metal element, or may contain two or more kinds in any combination and ratio.

  Examples of the imide compound include various alkali metal or alkaline earth metal imide compounds (that is, alkali metal imides and alkaline earth metal imides). Among them, alkaline earth metal imides are preferable, and particularly Sr. More preferred are imide compounds (for example, SrNH) and Ba imide compounds (for example, BaNH).

On the other hand, examples of the amide compound include various alkali metal or alkaline earth metal amide compounds (that is, alkali metal amide, alkaline earth metal amide), and specifically, M ¹ Ln ² ₂ (NH ₂ ) ₅ , M ¹ Ln ³ ₂ (NH ₂ ) ₇ , M ¹ ₃ Ln ² (NH ₂ ) ₅ , M ¹ ₃ Ln ³ (NH ₂ ) ₆ , M ¹ Al (NH ₂ ) ₄ , M ² Al (NH) ₂ ) ₅ and a compound represented by M ² (NH ₂ ) ₂ are included. Of these, an amide of an alkaline earth metal is preferable, a compound represented by M ² (NH ₂ ) ₂ is more preferable, and Ba (NH ₂ ) ₂ or Sr (NH ₂ ) ₂ is particularly preferable.
In the formula, “Ln ² ” represents a divalent lanthanoid element, and specifically represents one or more elements selected from the group consisting of Sm, Eu, and Yb. “Ln ³ ” represents a trivalent lanthanoid element, specifically, one or two selected from the group consisting of La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, and Tm. The above elements are represented. Furthermore, “M ¹ ” represents an alkali metal element, and specifically represents one or more elements selected from the group consisting of Li, Na, K, Rb, and Cs. “M ² ” represents an alkaline earth metal element, and specifically represents one or more elements selected from the group consisting of Mg, Ca, Sr and Ba. These definitions are the same throughout this “Imido-amide method” column.

  In the imide / amide method, only one kind of imide compound or amide compound may be used, or two or more kinds of imide compounds and / or amide compounds may be used in any combination and ratio.

  In the imide / amide method, the imide compound and the amide compound are used as an alkali metal and / or alkaline earth metal source of the phosphor. As the alkali metal and / or alkaline earth metal source, phosphor raw materials other than imide compounds and amide compounds may be used as necessary. In this case, the total proportion of the imide compound and amide compound in the total alkali metal and alkaline earth metal source is usually 50 mol% or more, preferably 70 mol% or more, more preferably 80 mol% or more, and still more preferably. 90 mol% or more, particularly preferably 95 mol% or more, and most preferably all are imide compounds and amide compounds.

  Although the said imide compound and amide compound may be purchased, they can be manufactured. Although there is no restriction | limiting in the manufacturing method of an imide compound and an amide compound, For example, it is compoundable with the manufacturing method demonstrated below.

  Examples of the method for producing the alkaline earth metal imide include a method of baking an alkaline earth metal in an ammonia atmosphere. The conditions will be described below.

  The firing step is usually carried out by weighing alkaline earth metal as a raw material, filling it in a heat-resistant container such as a crucible or tray made of a material having low reactivity, and firing it. As the material of the heat-resistant container used at the time of firing, for example, ceramics such as alumina, quartz, boron nitride, silicon carbide, silicon nitride, magnesium oxide, metals such as platinum, molybdenum, tungsten, tantalum, niobium, iridium, rhodium, or Examples thereof include alloys containing these 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. Of the materials for the heat-resistant container described above, alumina and metal are particularly preferable.

  The temperature during firing is usually in the range of 300 ° C. or higher, preferably 400 ° C. or higher, and usually 800 ° C. or lower, preferably 700 ° C. or lower. If the calcination temperature is too low, the formation reaction may not proceed sufficiently and the imide compound may not be sufficiently obtained. If the calcination temperature is too high, the generated imide compound may be decomposed, resulting in low reaction activity and N against metal elements. In some cases, a nitride which is a compound having a lower proportion than the imide compound is generated.

  The pressure during firing varies depending on the firing temperature and is not particularly limited, but is usually 0.01 MPa or more, preferably 0.05 MPa or more, and usually 200 MPa or less, preferably 100 MPa or less. Among these, the atmospheric pressure to about 1 MPa is industrially preferable in terms of cost and labor.

  The atmosphere during firing is an ammonia gas atmosphere. However, the atmosphere at the time of holding within the firing temperature range may be an ammonia gas atmosphere, and other atmospheres are not particularly limited.

  The firing time is not particularly limited because it varies depending on the temperature, pressure and the like during firing, but is usually 10 minutes or longer, preferably 30 minutes or longer, and usually 10 hours or shorter, preferably 6 hours or shorter. If the firing time is too short, the production reaction may be insufficient, and if it is too long, useless firing energy may be consumed and the production cost may be increased.

As a method for producing the alkali metal imide, there is a method of obtaining it by thermally decomposing an alkali metal amide described later.
The thermal decomposition temperature is usually 100 ° C. or higher, preferably 200 ° C. or higher, more preferably 250 ° C. or higher, still more preferably 300 ° C. or higher, and usually 500 ° C. or lower.
The pressure at the time of thermal decomposition may be appropriately set according to the stability of the imide compound to be generated, but is usually 0.05 MPa or more, preferably atmospheric pressure. However, when the stability of the imide compound to be produced is low, it may be under a pressure of usually 0.1 MPa or more, preferably 0.5 MPa or more. On the other hand, the upper limit is usually 10 MPa or less.
Further, as the atmosphere during thermal decomposition, N ₂ gas, it is possible to use an inert gas or ammonia gas, such as argon gas, and the like, preferably a N ₂ gas.
The pyrolysis time is not particularly limited because it varies depending on the temperature and pressure during firing, but is usually 10 minutes or longer, preferably 30 minutes or longer, and usually 10 hours or shorter, preferably 6 hours or shorter. .

Examples of the method for producing an amide compound of an alkali metal element and / or an alkaline earth metal element (that is, an alkali metal amide or an alkaline earth metal amide) include the following methods.
The raw material alkali metal and / or alkaline earth metal is placed in a stainless steel reaction tube and cooled to −30 ° C. Next, ammonia gas is fed into the reaction tube and condensed as liquid ammonia. Thereafter, the upper end of the reaction tube is closed, and the lower end is heated at a temperature of 80 ° C. or higher and 100 ° C. or lower and reacted for about 24 hours to dissolve the metal as a raw material in liquid ammonia. After completion of the reaction, the amide compound can be obtained by removing ammonia gas and taking out M ¹ NH ₂ or M ² (NH ₂ ) ₂ .
Further, in addition to alkali metal and / or alkaline earth metal, Al 1 metal, lanthanoid element metal or Y metal coexist in the reaction tube, so that M ¹ Al (NH ₂ ) ₄ , M ² Al (NH ₂ ) ₅ , amide compounds such as M ¹ Ln ² ₂ (NH ₂ ) ₅ , M ¹ Ln ³ ₂ (NH ₂ ) ₇ , M ¹ ₃ Ln ² (NH ₂ ) ₅ , M ¹ ₃ Ln ³ (NH ₂ ) ₆ Obtainable.

Next, a method for producing a phosphor by the imide / amide method will be described below.
As the phosphor raw material, at least one compound selected from the group consisting of alkali metal imides, alkali metal amides, alkaline earth metal imides, and alkaline earth metal amides is used. Furthermore, other compounds are also used as the phosphor material as required.

  The types and ratios of the imide compound and / or amide compound as the phosphor material and other compounds may be selected according to the composition of the phosphor to be manufactured. Specifically, the above-mentioned alkali metal imide, alkali metal amide, alkaline earth metal imide, alkaline earth metal amide and the like are mixed with various phosphor raw materials used according to the composition of the target phosphor ( (Mixing step), and firing the obtained mixture (firing step) to produce the target phosphor.

[Other phosphor materials]
Examples of the phosphor raw material other than the alkali metal imide, alkali metal amide, alkaline earth metal imide and alkaline earth metal amide used in the production of the phosphor of the present invention include, for example, the above-described elements constituting the phosphor. An imide compound and / or an amide compound of an element other than the alkali metal element and alkaline earth metal element that have been used can also be used.
Examples of the phosphor material other than the imide compound and / or the amide compound include, for example, metals, alloys, oxynitrides, nitrides, oxides, hydroxides, carbonates, nitrates, and the like of each element constituting the phosphor. Sulfates, oxalates, carboxylates, halides and the like can be arbitrarily used. From these compounds, the reactivity to the composite oxynitride and the low generation amount of NOx, SOx, etc. during firing may be selected as appropriate.

Specifically, as specific examples of the phosphor raw material (Eu source) containing Eu as an activator, 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 , EuF _{2 and the} like are preferable.

  Further, a phosphor material containing Ce (Ce source), a phosphor material containing Sm (Sm source), a phosphor material containing Tm (Tm source), a phosphor material containing Yb (Yb source), etc. Specific examples of the other activator element raw materials include compounds in which Eu is replaced with Ce, Sm, Tm, Yb, etc. in the respective compounds listed as specific examples of the Eu source.

Specific examples of phosphor raw materials (Ba source) containing Ba, which is an alkaline earth metal source, other than amide compounds and imide compounds 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 , Ba ₃ N ₂ , Ba ₂ N 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.
These Ba sources can be used in addition to the imide compounds and amide compounds described above, but as a ratio with respect to the entire phosphor raw material containing Ba (including imide compounds and amide compounds), in terms of a molar ratio of the Ba element. In general, it is used in a range of 50 mol% or less, preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 10 mol% or less, particularly preferably 5 mol% or less.

  For specific examples of other alkaline earth metal sources such as phosphor raw materials containing Sr (Sr source), phosphor raw materials containing Ca (Ca source), phosphor raw materials containing Mg (Mg source), etc. What is necessary is just to read the description as said Ba source regarding each element.

As a specific example of the phosphor raw material (Si source) containing Si, it is preferable to use SiO ₂ or Si ₃ N ₄ , and more preferably Si ₃ N ₄ . 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. Further, Si ₃ N ₄ is preferably one having a small particle diameter 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 more preferable than α-Si ₃ N ₄ , and in particular, a material having a small content of carbon elements as impurities is more preferable. The carbon content is preferably as small as possible, but is usually 0.01% by weight or more, usually 0.3% by weight or less, preferably 0.1% by weight or less, more preferably 0.05% by weight or less. is there.

  4 such as a phosphor raw material containing Ge (Ge source), a phosphor raw material containing Ti (Ti source), a phosphor raw material containing Zr (Zr source), a phosphor raw material containing Hf (Hf source), etc. Regarding the valent metal element, the description as the Si source may be read for each element.

Specific examples of the phosphor raw material (Al source) containing Al include AlO ₂ and AlN.

  Further, the N element in the phosphor composition as a nitride and the O element in the phosphor composition as an oxynitride are usually contained as anion components of the raw materials of the above constituent elements or in a firing atmosphere. As a component, it is supplied at the time of manufacturing the phosphor.

[Mixing process]
The phosphor raw material is weighed and mixed so as to obtain the target composition to prepare a phosphor raw material mixture, and then the phosphor raw material mixture is baked in a predetermined temperature and atmosphere to obtain the phosphor of the present invention. Obtainable. In this case, it is preferable that the mixing is sufficiently performed using a ball mill or the like.

Although it does not specifically limit as said mixing method, Specifically, the well-known method which was mentioned as following (A) and (B) can be used arbitrarily. 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) Add a solvent or dispersion medium selected from water or ethanol-based solvent such as ethanol to the phosphor raw material, and mix using, for example, a pulverizer, a mortar and pestle, or an evaporating dish and a stirring bar, A wet mixing method in which a solution or slurry is made and then dried by spray drying, heat drying, or natural drying.

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

  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 raw materials. However, in the production method of the present invention, since an imide compound and / or an amide compound are used as the phosphor material, inert materials such as argon gas and nitrogen gas are used so that the phosphor material does not deteriorate due to moisture. It is preferable to mix with a glove box filled with gas and controlled in moisture. The moisture in the workplace where mixing is performed 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 phosphor raw material 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 include preferably heat-resistant containers made of boron nitride, alumina, silicon nitride, silicon carbide, platinum, molybdenum, tungsten, and tantalum.

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

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, and preferably 1500 ° C. or lower, more preferably 1200 ° C. or lower, and still more preferably 1000 ° C. or lower, In general, it is preferably in the range of 10 ⁻² Pa to 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.

As the firing temperature for producing the phosphor of the present invention, if the firing temperature is too low, the crystals do not grow sufficiently and the particle size may be reduced. On the other hand, the firing temperature is too high. In such a case, there is a possibility that the emission intensity may be low, so that the light emission intensity may be arbitrarily set in accordance with the target phosphor based on these viewpoints. Specifically, the phosphor represented by (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : R and (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : R When the phosphor represented by (R is an activating element) is produced, the firing temperature is usually 1000 ° C. or higher, preferably 1300 ° C. or higher, more preferably 1500 ° C. or higher, The temperature is usually 2000 ° C. or lower, preferably 1900 ° C. or lower, more preferably 1850 ° C. or lower, and still more preferably 1800 ° C. or lower.

  Although it does not restrict | limit especially as a baking atmosphere, Usually, it carries out in inert gas atmosphere or reducing atmosphere. Here, as the valence of the activating element, it is preferable that the valence is more divalent, and therefore 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, and the like. Of these, a nitrogen gas atmosphere is preferable. In this case, it is preferable to use a nitrogen (N ₂ ) gas having a purity of 99.9% or more.

  Further, it is preferable to use a reducing gas in combination with the nitrogen gas. In this case, the type of reducing gas to be combined with nitrogen gas may be appropriately selected depending on the type of firing furnace to be used, but hydrogen gas is preferably used. Therefore, the firing atmosphere is preferably a hydrogen-containing nitrogen atmosphere. Thus, when using hydrogen-containing nitrogen, it is preferable to lower the oxygen concentration in the electric furnace to 20 ppm or less. Furthermore, the hydrogen content in the atmosphere is preferably 1% by volume or more, more preferably 2% by volume or more, and preferably 5% by volume or less. 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.

  Further, when the heating element of the firing furnace is carbon, a strong reducing atmosphere is obtained at a high temperature without intentionally introducing a reducing gas into the firing furnace. An effect of suppressing excessive oxygen from being taken into the body is obtained.

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. Among them, it is preferable to introduce before starting the temperature increase or during the temperature increase.
Moreover, you may make it distribute | circulate atmospheric gas in the case of baking. In this case, the flow rate of the atmospheric gas is arbitrary, but when nitrogen gas is used as the atmospheric gas, the flow rate of the nitrogen gas flow is preferably 1 × 10 ⁻⁴ m ³ / s or less. More preferably, it is 5 × 10 ⁻⁵ m ³ / s or less, particularly preferably 1 × 10 ⁻⁵ m ³ / s or less, and usually more than 0. By setting the flow rate of the nitrogen gas flow within this range, the time during which hydrogen gas by-produced from the imide compound and the amide compound exists in the vicinity of the phosphor raw material becomes long, and the vicinity of the raw material tends to be a reducing atmosphere.

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, in terms of industrial cost and labor, a pressure of about atmospheric pressure to about 1 MPa is convenient and preferable. In particular, within the above pressure range, when firing in an N ₂ atmosphere, phosphor materials such as silicon nitride, which are phosphor materials other than imide compounds and amide compounds, decompose before reaching the reaction temperature. In order to suppress this, the N ₂ gas partial pressure is usually greater than 0.1 MPa, preferably 0.5 MPa or more, and usually 200 MPa or less, preferably 100 MPa or less.

  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.

〔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, Alkali metal halides such as NaF, KF and CsF; Alkaline earth metal halides such as CaCl ₂ , BaCl ₂ , SrCl ₂ , CaF ₂ , BaF ₂ and SrF ₂ ; Alkaline earth metal oxides such as CaO, SrO and BaO Boron oxide, boric acid and borate compounds such as B ₂ O ₃ , H ₃ BO ₃ , NaB ₄ O ₇ ; Phosphate compounds such as Li ₃ PO ₄ and NH ₄ H ₂ PO ₄ ; AlF ₃ aluminum halides _etc.; ZnCl 2, zinc halide such as ZnF _2, zinc oxide, zinc compounds such as zinc sulfide; B Periodic Table Group 15 element compound such as _{2 O 3; Li 3 N,} Ca 3 N 2, Sr 3 N 2, Sr 2 N, Ba 3 N 2, Ba 2 N, BN alkali metals, alkaline earth metals such as such as Examples thereof include nitrides of metals or Group 13 elements. Of these, preferred are halides, and among these, alkali metal halides, alkaline earth metal halides, and Zn halides are preferred. Of these halides, fluorides and chlorides are preferred.

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, more preferably 0.1% by weight or more, and usually 20% by weight or less, A range of 10% by weight or less is preferred. 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 luminance will decrease. May cause. These fluxes may use only 1 type and may use 2 or more types together by arbitrary combinations and ratios.
Here, it is preferable to use an anhydride for the above-mentioned flux having deliquescence, and when the phosphor is produced by multi-stage firing, it is preferred to use the flux at the later stage firing.

[Primary firing and secondary firing]
In addition, you may divide a baking process into primary baking and secondary baking. For example, a phosphor mixture obtained by mixing phosphor raw materials other than an imide compound and an amide compound is first calcined and then ground again with a ball mill or the like, and then the primary calcined product and the imide compound and / or amide compound are combined. You may mix and perform secondary 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 the secondary firing. Also, the firing conditions such as the atmosphere may be changed between the primary firing and the secondary firing. Further, in the above firing, when the number of crucibles in the firing furnace is large, for example, the heat transfer rate to each crucible is evenly fired, for example, by slowing the temperature increase rate. This is preferable.

[Other processes]
In the production method of the present invention, steps other than those described above may be performed as long as the effects of the present invention are not significantly impaired. For example, after the heat treatment in the above-described firing step, post-treatment steps such as pulverization, washing, drying, and classification treatment may be performed as necessary.

  The pulverization treatment is performed on the fired product when, for example, the obtained phosphor does not have a desired particle size. Although it does not specifically limit as a grinding | pulverization process method, For example, the dry-type grinding | pulverization method and wet-grinding method described in the term of the description of the mixing process of a phosphor raw material can be used.

  The cleaning 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. In addition, for the purpose of removing the impurity phase adhering to the phosphor surface such as the flux used and improving the light emission characteristics, for example, an inorganic acid such as hydrochloric acid, nitric acid, sulfuric acid; or an organic acid such as acetic acid. An aqueous solution of 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.).

  The classification treatment can be performed, for example, by performing a water sieving or water tank treatment, or by using various classifiers such as various air classifiers or vibrating sieves. In particular, when dry classification using a nylon mesh is used, a phosphor with good dispersibility having a weight median diameter of about 20 μm can be obtained.

  Further, when a light-emitting device is produced by the method described later using the obtained phosphor of the present invention, the phosphor-containing portion 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 with respect to 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. Examples thereof include metal oxides such as bismuth, metal nitrides such as silicon nitride and aluminum nitride, orthophosphates such as calcium phosphate, barium phosphate and strontium phosphate, polyphosphates, combinations of sodium phosphate and calcium nitrate, 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 phosphor surface.
(Ii) A mode in which the surface treatment substance becomes a large number of fine particles and adheres to the surface of the phosphor to cover the phosphor surface.

  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 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 phosphor surface 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 reduced-pressure 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. Phosphor]
[2-1. Characteristics of phosphor]
[Characteristics related to emission spectrum]
The phosphor of the present invention obtained by the imide / amide method described above has higher emission intensity (emission peak relative intensity) than the phosphor obtained by the conventional method. That is, the phosphor of the present invention emits light with higher brightness than the phosphor obtained by the conventional method when excited under the same conditions.

  Moreover, the phosphor of the present invention usually has a narrow half-value width of the emission peak of the emission spectrum. That is, in the phosphor of the present invention, the half width of the emission peak in the emission spectrum observed when excited under the same conditions is usually narrower than the phosphor obtained by the conventional method.

[Characteristics related to excitation spectrum]
The phosphor of the present invention is preferably excitable with light having 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 is the ratio of the emission peak intensity value in the emission spectrum diagram when irradiated with light of 410 nm to the emission peak intensity value in the emission spectrum diagram when irradiated with light of a wavelength of 390 nm. Is preferably 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.

  The phosphor of the present invention can be excited using, for example, a GaN-based LED, and the measurement of the emission spectrum of the phosphor of the present invention and the calculation of the emission peak wavelength, peak relative intensity and peak half width are as follows. For example, a 150 W xenon lamp can be used as an excitation light source, and a fluorescence measuring apparatus (manufactured by JASCO Corporation) including a multichannel CCD detector C7041 (manufactured by Hamamatsu Photonics) can be used as a spectrum measuring apparatus.

[Quantum efficiency]
The phosphor of the present invention has a higher external quantum efficiency than conventional phosphors having the same composition. Specifically, the external quantum efficiency is usually 0.35 or more, more preferably 0.4 or more, further preferably 0.45 or more, and particularly preferably 0.5 or more. In order to design a light emitting device with high emission intensity, the higher the external quantum efficiency, the better.

  Further, as the internal quantum efficiency of the phosphor of the present invention, its value 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. 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 is preferably as its absorption efficiency is high. The value is usually 0.5 or more, preferably 0.6 or more, more preferably 0.65 or more, and still more 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.

[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 A) 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 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).

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 (Formula B) is the same as the integration interval defined in (Formula A). By limiting the integration interval in this way, the second term of (Formula B) corresponds to the number of photons generated when the phosphor sample to be measured reflects the 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 A) and (Equation B) are obtained by the sum based on the bandwidth.
From the above, αq = N _abs / N = (Formula B) / (Formula A).

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 C).

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 C) is the upper end of the integration interval of (Equation A), 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 = (formula C) / (formula B).

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 C) / (Formula A). 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.

[Weight median diameter]
The phosphor of the present invention has a weight median diameter 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 The range is preferably 20 μm or less. When the weight median diameter is too small, the luminance decreases and the phosphor particles tend to 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 weight median diameter of the phosphor of the present invention can be measured using a device such as a laser diffraction / scattering particle size distribution measuring device.

[2-2. 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. Further, 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.

[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. 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. Specifically, for example, methacrylic resin such as polymethylmethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; Cellulose resins such as cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins.

  Among these, in particular, when a phosphor is used for a high-power light-emitting device such as illumination, it is preferable to use a silicon-containing compound as a liquid medium for the purpose of heat resistance and light resistance.

  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 resin), condensation curing type (condensation type silicone resin), 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 polyorganosiloxane chains are crosslinked by organic addition bonds. 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 the 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, and u is 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. The liquid medium may be used alone or in combination of two or more 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 comprising the above-mentioned [2. The phosphor of the present invention described in the section of “phosphor” contains at least one kind of phosphor 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 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. 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.

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

  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 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.

[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 contains the phosphor of the present invention described above as the first phosphor. In addition, a second phosphor (a red to orange phosphor, a green phosphor, a blue phosphor, a yellow phosphor, or the like), which will be described later, is appropriately contained 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.
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, as the first phosphor, another type of orange or red phosphor can be used together with the phosphor of the present invention. When the phosphor of the present invention is a blue phosphor, Can be used together with the phosphor of the present invention in combination with another type of blue phosphor, and when the phosphor of the present invention is a yellow phosphor, the first phosphor 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)
The emission peak wavelength of the green phosphor 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, 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.

As a specific example of the green phosphor, europium activation represented by (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu that is composed of fractured particles having a fracture surface and emits light in the green region. Examples thereof include alkaline earth silicon oxynitride phosphors.

Other green phosphors include Eu-activated aluminate phosphors such as Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu, and (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, Ce, Tb-activated silicate phosphors such as Tb, Sr ₂ P 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: M such as Mn Activated silicate _{phosphors, CeMgAl 11 O 19: Tb,} Y 3 Al 5 O 12: Tb -activated aluminate phosphors 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, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce-activated aluminate phosphor such as Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce activated silicate phosphor such as Ce, Ce activated oxide phosphor such as CaSc ₂ O ₄ : Ce, Eu-activated oxynitride phosphors such as Eu-activated β sialon BaMgAl ₁₀ O _17: Eu, Eu such as Mn, Mn-activated aluminate phosphor, SrAl ₂ O _4: Eu-activated aluminate phosphor such as _{Eu, (La, Gd, Y} ) 2 O 2 S: Tb-activated oxysulfide phosphors such as Tb, LaPO ₄ : Ce, Tb-activated phosphate phosphors such as Ce, Tb, and sulfide phosphors such as ZnS: Cu, Al, ZnS: Cu, Au, 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: Ce, Tb activated borate phosphors such as K, Ce, Tb, Eu, Mn activated halosilicate phosphors such as Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, Mn, (Sr, Ca, Ba _{) (Al, Ga, in)} 2 S 4: Eu activated thioaluminate such as Eu Light body and thiogallate _{phosphor, (Ca, Sr) 8 (} Mg, Zn) (SiO 4) 4 Cl 2: Eu, Eu such as Mn, Mn-activated halo silicate _{phosphor, 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

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 naphthalic acid-imide-based fluorescent dye, or an organic phosphor such as a terbium complex. is there.
Any of the green phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

(Orange to red phosphor)
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 represented by (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu that is composed of fractured particles having a red fracture surface and emits light in the red region. The activated alkaline earth silicon nitride phosphor is composed of grown 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: Eu And europium activated rare earth oxychalcogenide phosphors represented by

  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 red phosphors include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu, Y (V, P) O ₄ : Eu, and Y ₂ O ₃ : Eu. Eu-activated oxide phosphor, (Ba, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn-activated silicate phosphor such as Eu, Mn, Eu-activated tungstate phosphors 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 (Ca, Sr) S: Eu-activated sulfide phosphors such as Eu, YAlO ₃ : Eu-activated aluminate phosphors such as 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: Eu, Sr 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 phosphor such as Ce, (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, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu such as Eu, Mn Mn-activated halophosphate phosphor, Ba ₃ MgSi ₂ O ₈ : Eu, Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu, Mn-activated silicate _{phosphor, 3.5MgO · 0.5MgF 2 · GeO 2} : Mn such as Mn Tsukekatsuge Man salt phosphor, Eu Tsukekatsusan nitride phosphor such as Eu-activated _{α-sialon, (Gd, Y, Lu,} La) 2 O 3: Eu, Eu Bi, etc., Bi-activated oxide phosphor, (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, such as Eu, Bi Activated vanadate phosphor, SrY ₂ S ₄ : Eu, Ce activated sulfide phosphor such as Eu, Ce, etc., CaLa ₂ S ₄ : Ce activated sulfide phosphor such as Ce, (Ba, Sr, Ca, etc.) _{) 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: u, Ce (provided that, x, y, z are 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.

Moreover, among the above examples, (Sr, Ba) ₃ SiO ₅ : Eu is 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)
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, more preferably 460 nm or less. It is preferable that it exists in.

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-based 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): Europium-activated calcium halophosphate phosphor represented by Eu, and a growth crystal having a substantially cubic shape as a regular crystal growth shape, and emits light in a blue region (Ca, Sr, Ba) ₂ B ₅ Europium-activated alkaline earth chloroborate phosphor represented by O ₉ Cl: Eu, fractured particles having fractured surfaces Europium-activated alkaline earth aluminate system represented by (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba) ₄ Al ₁₄ O ₂₅ : Eu Examples thereof include phosphors.

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 phosphors such as Sb, Sb, BaAl ₂ Si ₂ O ₈ : Eu, (Sr, Ba) ₃ MgSi ₂ O ₈ : Eu-activated silicate phosphors 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 ON ₃₁ , La _1-x Ce _x Al (Si _6-z Al _z ) (N _10-z O _z ) (where x and y are numbers satisfying 0 ≦ x ≦ 1 and 0 ≦ z ≦ 6, respectively), La _1-xy Ce _x Ca _y Al (Si _6-z Al _z ) (N _10-z O _z ) (where x, y, and z are 0 ≦ x ≦ 1, 0 ≦ y ≦, respectively. It is also possible to use Eu-activated oxynitride phosphors such as 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 preferable 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)
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 there.

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 phosphors such as oxynitride phosphors having a sialon structure such as Eu, and alkaline earth metals It is also possible to use a rare earth activated silicon nitride phosphor having a good La ₃ Si ₆ N ₁₁ structure.

Examples of yellow phosphors include brilliant sulfoflavine FF (Color Index Number 56205), basic yellow HG (Color Index Number 46040), eosine (Color Index Number 45G80), 45G 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.

(Sealing material)
In the light emitting device of the present invention, the first and / or second phosphors are usually used after being dispersed and sealed in a liquid medium which is a sealing material, and then cured by heat or light.
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 amorphous or crystalline, but in order to give a high refractive index, a crystalline structure is preferred. 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.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless departing from the gist thereof.

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

[Powder X-ray diffraction measurement method]
In each Example described later, powder X-ray diffraction was precisely measured by a powder X-ray diffractometer X′Pert made by PANalytical. The measurement conditions are as follows.
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

[Measurement method of emission spectrum]
The emission spectrum was measured using a 150 W xenon lamp as an excitation light source and a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with 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 340 nm, 400 nm or 455 nm was irradiated to the phosphor through the optical fiber. The light generated from the phosphor by the irradiation of the 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. The emission spectrum and brightness were measured 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. A higher relative emission peak intensity is preferred.

[Measurement method of chromaticity coordinates]
From data in the wavelength region of 380 nm to 800 nm (in the case of excitation wavelength 340 nm), 430 nm to 800 nm (in the case of excitation wavelength 400 nm) or 480 nm to 800 nm (in the case of excitation wavelength 455 nm) of the emission spectrum, in a method according to JIS Z8724, Chromaticity coordinates CIEx and CIEy in the XYZ color system defined by JIS Z8701 were calculated.

[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, a phosphor sample to be measured was packed in a cell with a sufficiently smooth surface so that 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 (having a reflectance R of 98% with respect to the excitation light having a wavelength of 450 nm), which is a reflector having a reflectance R of almost 100% with respect to the excitation light, is measured. The reflection spectrum I _ref (λ) was measured by attaching to the integrating sphere described above in 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]
Measurement was performed using CILAS laser diffraction / scattering particle size distribution measuring apparatus model 1064 using water as a dispersion medium.

[Example 1]
First, SrNH was produced by the following method.
In a glove box filled with high-purity argon gas, 3.15666 g of Sr metal was weighed with an electronic balance and placed on an Al ₂ O ₃ boat. This was further put into a quartz glass tube, and a valve was attached to both ends of the quartz glass tube and sealed. The quartz glass tube was taken out from the glove box and set in a tubular furnace. Next, the tips of the bulbs at both ends of the quartz glass tube were connected to an ammonia gas line. After reducing the pressure in the quartz glass tube to about 5 × 10 ⁻³ Pa, the rotary pump was stopped and high-purity ammonia gas was allowed to flow at 10 to 100 ml / min for 1 hour. Then, after heating up to 250 degreeC over 1 hour, it maintained for 1 hour. Further, the temperature was raised to 650 ° C. over 2 hours, maintained for 4 hours, and then allowed to cool to room temperature. After firing, the quartz glass tube was taken into the glove box and stored with the valves at both ends closed. The compound SrNH thus obtained was used as a starting material for the phosphor described later. The powder X-ray diffraction spectrum of the obtained SrNH is shown in FIG.

Subsequently, a phosphor Sr ₂ Si ₅ N ₈ : Eu was manufactured by the following method.
As a phosphor raw material, 0.4638 g of the above-mentioned SrNH and Si ₃ N ₄ (manufactured by Ube Industries Co., Ltd.) are used so that the composition ratio is (Sr _0.992 Eu _0.008 ) ₂ Si ₅ N _8. 0.5283 g, 0.0080 g of Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd.) was used. These phosphor materials were weighed by an electronic balance in a glove box filled with high-purity argon gas. In the glove box, all these phosphor materials were pulverized and mixed in an alumina mortar until they were uniform, and the mixed powder was filled in a boron nitride crucible and molded under a light load.

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 the inside of the furnace was depressurized to less than 5 × 10 ⁻³ Pa to be almost vacuum. The temperature was raised from room temperature at a heating rate of 20 ° C./min, and when the temperature reached 800 ° C., introduction of high-purity nitrogen gas (99.9995%) was started. While maintaining the furnace temperature at 800 ° C., nitrogen gas was continuously introduced for 30 minutes until the pressure in the furnace reached 0.92 MPa. While maintaining the pressure of the high-purity nitrogen gas at 0.92 MPa, the temperature was further increased to 1200 ° C. at a rate of temperature increase of 20 ° C./min, maintained as it was for 5 minutes, and changed from a thermocouple to a radiation thermometer.

Next, while measuring with a radiation thermometer, the temperature was increased to 1600 ° C. at a temperature increase rate of 20 ° C./min, maintained at 1600 ° C. for 2 hours, and then increased to 1800 ° C. at a temperature increase rate of 20 ° C./min. Maintained at 1800 ° C. for 2 hours. Then, it cooled to 1200 degreeC with the temperature-fall rate of 20 degree-C / min, and then left to cool. The obtained fired product was pulverized in the air using an alumina mortar for 30 minutes to obtain a phosphor (Sr _0.992 Eu _0.008 ) ₂ Si ₅ N ₈ powder.
Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. From FIG. 5, it can be seen that the phosphor has a substantially single phase formed of Sr ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The results are shown in FIG. 7, and the emission spectrum characteristics are shown in Table 1.

[Comparative Example 1]
As raw materials, 1.96 mol of SrCO ₃ , 1.66 mol of Si ₃ N ₄ and 0 of Eu ₂ O ₃ are used as raw materials so that the composition ratio is (Sr _0.98 Eu _0.02 ) ₂ Si ₅ N _8. These were weighed at a ratio of 0.02 mol and mixed well. The obtained raw material mixture is placed in a carbon (graphite) crucible and fired by heating at a pressure of 0.92 MPa and a temperature of 1800 ° C. for 2 hours using a resistance heating type vacuum heat treatment furnace manufactured by Fuji Denpa Kogyo. Performed (primary firing). After firing, the powder is pulverized in an alumina mortar, and the resulting powder is placed in a boron nitride crucible and heated at a pressure of 0.92 MPa and a temperature of 1800 ° C. for 2 hours in a resistance heating vacuum pressurizing atmosphere heat treatment furnace manufactured by Fuji Denpa Kogyo. Thus, firing was performed again (secondary firing). The obtained fired product was pulverized in an alumina mortar to obtain a phosphor (Sr _0.98 Eu _0.02 ) ₂ Si ₅ N ₈ powder.

Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. From FIG. 6, it can be seen that the phosphor has a substantially single phase formed of Sr ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The result is shown in FIG.

[Comparison between Example 1 and Comparative Example 1]
The emission peak half-value width of the phosphor of Comparative Example 1 is 96 nm, whereas the emission peak half-value width of the phosphor of Example 1 is 83 nm. As is apparent from the emission spectrum of FIG. It can be seen that by using the production method, the half-value width of the emission peak of the obtained phosphor can be narrowed, and in addition, the emission peak wavelength can be shortened.

  Further, when the luminance of each phosphor was calculated from the emission spectrum of FIG. 7, the luminance of the phosphor of Example 1 was improved about 1.3 times that of the phosphor of Comparative Example 1. In addition, although the Eu content differs between the phosphor of Example 1 and the phosphor of Comparative Example 1, such a large change in half-value width or luminance is mainly observed due to a difference in manufacturing method.

From these results, since SrNH has a lower oxygen content than SrCO ₃ , it can be used as a phosphor material to reduce the oxygen content in the obtained phosphor and improve the luminance of the phosphor. I guess it was possible.

On the other hand, Sr ₂ N can also be used as the Sr source of the phosphor, but Sr ₂ N is unstable in the air, and since the ratio of N to Sr is low, the resulting phosphor is crystalline. It tends to cause defects.
On the other hand, since SrNH has a higher ratio of N to Sr than Sr ₂ N, crystal defects are unlikely to occur in the obtained phosphor, and as a result, the crystallinity of the phosphor is improved, and the luminance enhancement effect is obtained. It is thought that it was done.
Furthermore, since hydrogen (H) contained in SrNH reacts with oxygen (O) during firing to produce water (H ₂ O), the oxygen concentration in the obtained phosphor can be further reduced. It is guessed.

  As described above, by using SrNH as a phosphor raw material, only the effect of reducing the oxygen concentration of the phosphor and improving the crystallinity and purity of the resulting phosphor, thereby improving the luminance of the phosphor obtained. Rather, the effect that the peak of the emission spectrum of the phosphor becomes sharp (that is, the half-value width of the emission peak becomes narrow) is obtained by making the ambient environment of the activation element such as Eu more uniform. It is guessed that there is not.

[Example 2]
As a phosphor raw material, 0.9115 g of SrNH obtained in the same manner as in Example 1 and 1.3 of Si ₃ N ₄ were used so that the composition ratio was (Sr _0.98 Eu _0.02 ) ₂ Si ₅ N ₈ . 0576 g and 0.0311 g of Eu ₂ O ₃ were used. These phosphor materials were weighed by an electronic balance in a glove box filled with nitrogen gas. All these phosphor raw materials were pulverized and mixed in an alumina mortar in a glove box, and the mixed powder was filled in a boron nitride crucible.

  This boron nitride crucible was placed in a resistance heating vacuum pressurizing atmosphere heat treatment furnace manufactured by Fuji Denpa Kogyo Co., Ltd., heated in the same manner as in Example 1, under a nitrogen gas atmosphere (pressure 0.92 MPa), 1400 ° C., Firing was performed for 2 hours, and then firing was performed at 1600 ° C. for 2 hours. Furthermore, this sample was fired again at 1600 ° C. for 2 hours in a nitrogen gas atmosphere (pressure 0.92 MPa) using a resistance heating vacuum pressurizing atmosphere heat treatment furnace manufactured by Fuji Radio Industry Co., Ltd., then 1800 ° C., 2 The phosphor was obtained by firing over time.

Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. FIG. 8 shows that the phosphor has a single phase composed of Sr ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The results are shown in FIG. 7, and the emission spectrum characteristics are shown in Table 2.

[Example 3]
First, Sr (NH ₂ ) ₂ was produced by the following method.
In a glove box filled with argon gas, 0.5370 g of Sr metal (99.9%) manufactured by Aldrich was weighed with an electronic balance, and this was put into a stainless steel reaction tube equipped with a pressure gauge. The reaction tube was taken out of the glove box, and then the end of the reaction tube was cooled with a refrigerant made by putting dry ice in isopropyl alcohol. Next, the ammonia gas line was connected to a valve provided in the reaction tube. Ammonia gas was slowly introduced into the reaction tube and taken into the reaction tube as liquefied ammonium, and then the valve was closed. Thereafter, the reaction tube was taken out of the refrigerant, and the end portion of the reaction tube was heated at 85 ° C. and held for 48 hours. During this time, Sr metal reacted with liquefied ammonia to generate hydrogen gas, and the gauge pressure became 2.8 MPa. After the reaction, ammonia gas was removed, and then the inside of the reaction tube was replaced with nitrogen gas. Sr (NH ₂ ) ₂ in the reaction tube was scraped out in the glove box. The obtained sample was 0.3135 g. The compound Sr (NH ₂ ) ₂ thus obtained was used as a starting material for the phosphor described later.

Subsequently, a phosphor Sr ₂ Si ₅ N ₈ : Eu was manufactured by the following method.
As a phosphor raw material, 0.2477 g of the above-mentioned Sr (NH ₂ ) ₂ and 0.2463 g of Si ₃ N ₄ are used so that the composition ratio is (Sr _0.98 Eu _0.02 ) ₂ Si ₅ N ₈ . A phosphor was obtained in the same manner as in Example 2 except that 0.0078 g of Eu ₂ O ₃ was used and baking was performed at 1400 ° C. for 2 hours and further at 1600 ° C. for 2 hours. The obtained sample was pulverized using an alumina mortar to obtain a phosphor.

Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. FIG. 8 shows that the phosphor has a single phase composed of Sr ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The results are shown in FIG. 9, and the emission spectrum characteristics are shown in Table 3.

[Comparison between Example 3 and Comparative Example 1]
Compared with Comparative Example 1 (secondary firing: 1800 ° C., 2 hours), Example 3 has a light emission intensity even under a low firing temperature where high crystallinity exhibiting excellent light emission characteristics cannot be expected. It was excellent. In addition, the emission peak half-value width of Comparative Example 1 was 98 nm, whereas the emission peak average half-value width of Example 3 was 81 nm, and the half-value width was narrowed. In addition, from the emission spectrum shown in FIG. 9, the emission peak wavelength was shortened.

[Example 4]
First, CaNH was produced by the following method.
2.3353 g of CaNH was obtained in the same manner as in the production of SrNH in Example 1, except that 1.7933 g of Ca metal (99.9%) manufactured by Aldrich was used and the reaction time at 650 ° C. was changed to 2 hours. It was.

Powder X-ray diffraction measurement was performed on the obtained sample. The powder X-ray diffraction spectrum is shown in FIG. FIG. 10 shows that the obtained sample is a CaNH single phase. In FIG. 10, the broad peak having a peak at 26 ° is due to the Mylar film placed on the sample surface in order to prevent moisture absorption of the sample powder.
The compound CaNH thus obtained was used as a starting material for the phosphor described later.

Subsequently, the phosphor Ca ₂ Si ₅ N ₈ : Eu was manufactured by the following method.
As the phosphor raw material, 0.6192 g of CaNH, 1.3402 g of Si ₃ N ₄ , and Eu ₂ O ₃ of 0 are used as phosphor raw materials so that the composition ratio is (Ca _0.98 Eu _0.02 ) ₂ Si ₅ N _8. 0.0404 g was used, and a phosphor was obtained in the same manner as in Example 2 except that firing was performed at 1400 ° C. for 2 hours, and further at 1600 ° C. for 2 hours. The obtained phosphor was pulverized in an alumina mortar to obtain a phosphor powder.

Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. From FIG. 11, it can be seen that the phosphor has a substantially single phase formed of Ca ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The results are shown in FIG. 12, and the emission spectrum characteristics are shown in Table 4.

[Comparative Example 2]
The starting material CaNH in Example 4 was changed to Ca ₃ N ₂ , 0.5733 g of this Ca ₃ N ₂ , 1.3846 g of Si ₃ N ₄ and 0.0418 g of Eu ₂ O ₃ were weighed, and in an alumina mortar After pulverizing and mixing, the same baking treatment as in Example 4 was performed to obtain a phosphor.

Powder X-ray diffraction measurement was performed on the obtained phosphor. The powder X-ray diffraction spectrum is shown in FIG. From FIG. 11, it can be seen that the phosphor has a substantially single phase formed of Ca ₂ Si ₅ N ₈ .
In addition, an emission spectrum was measured at an excitation wavelength of 455 nm. The results are shown in FIG. 12, and the emission spectrum characteristics are shown in Table 4.

  From Table 4, it can be seen that the phosphor using CaNH as a starting material is superior in emission peak intensity.

  The use of the phosphor of the present invention is not particularly limited, and can be used in various fields where ordinary phosphors are used, but takes advantage of its excellent conversion efficiency and color purity for blue light or near ultraviolet light. Therefore, it is suitable for the purpose of realizing a general illuminant that is excited by a light source such as a near-ultraviolet LED or a blue LED, particularly a white illuminant for a backlight having a high luminance and a wide color reproduction range.

  Further, the light emitting device of the present invention using the phosphor of the present invention having the above-described characteristics can be used in various fields where a normal light emitting device is used. And particularly preferably used.

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 views showing an embodiment of a light emitting device having an excitation light source (first light emitter) and a phosphor-containing portion (second light emitter). It is sectional drawing. It is sectional drawing which shows typically one Embodiment of the illuminating device of this invention. It is a figure showing the powder X-ray-diffraction spectrum of SrNH manufactured in Example 1 of this invention. It is a figure showing the powder X-ray-diffraction spectrum of the fluorescent substance of Example 1 of this invention. 3 is a diagram illustrating a powder X-ray diffraction spectrum of a phosphor of Comparative Example 1. FIG. It is a figure showing the emission spectrum in excitation wavelength 455nm of the fluorescent substance of Example 1, Example 2, and Comparative Example 1 of this invention. It is a figure showing the powder X-ray-diffraction spectrum of the fluorescent substance of Examples 1-3 of this invention. It is a figure showing the emission spectrum in the excitation wavelength of 455 nm of the fluorescent substance of Example 3 of this invention, and the comparative example 1. FIG. It is a figure showing the powder X-ray-diffraction spectrum of CaNH manufactured in Example 4 of this invention. It is a figure showing the powder X-ray-diffraction spectrum of the fluorescent substance of Example 4 and Comparative Example 2 of this invention. It is a figure showing the emission spectrum in excitation wavelength 455nm of the fluorescent substance of Example 4 and Comparative Example 2 of this invention.

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: Phosphor-containing resin part (second light emitter)
24: Frame 25: Conductive wire 26, 27: Electrode

Claims (11)

A method for producing a phosphor, comprising a step of firing a phosphor raw material mixture containing a compound selected from the group consisting of an alkali metal imide, an alkali metal amide, an alkaline earth metal imide, and an alkaline earth metal amide. The manufacturing method according to claim 1, wherein the firing is performed in an atmosphere containing N ₂ gas. The production method according to claim 2, wherein the N ₂ gas partial pressure is greater than 0.1 MPa and equal to or less than 200 MPa. The method according to claim 2 or 3, characterized in that a nitrogen flow under the firing ^{0~1 × 10 -4 m 3 / s} . The phosphor is (Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : R, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : R, (Mg, Ca, Sr , Ba) ₃ Si ₆ O ₁₂ N ₂ : R, (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : R or (Mg, Ca, Sr, Ba) _x (Si, Al) ₁₂ (O, N: ₁₆ : R (R is an activating element, and x is a numerical value satisfying 0 <x <1). 5. Production method. A phosphor obtained by the manufacturing method according to claim 1. A phosphor-containing composition comprising the phosphor according to claim 6 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 at least one of the phosphors according to claim 6 as a first phosphor. 9. The light emitting device according to claim 8, 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 8. An image display device comprising the light-emitting device according to claim 8.

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