JP5403134B2 - Phosphor and light emitting device using the same - Google Patents

Description

  The present invention relates to a high-luminance phosphor based on nitride or oxynitride. The present invention also relates to a phosphor-containing composition and a light emitting device using the phosphor, and an image display device and an illumination device using the light emitting device.

  Phosphors are used in fluorescent lamps, fluorescent display tubes (VFD), field emission displays (FED), plasma display panels (PDP), cathode ray tubes (CRT), white light emitting diodes (LEDs) and the like. In any of these applications, in order to make the phosphor emit light, it is necessary to supply the phosphor with energy for exciting the phosphor, and the phosphor is not limited to vacuum ultraviolet rays, ultraviolet rays, visible rays, electron beams, etc. When excited by an excitation source having high energy, it emits ultraviolet rays, visible rays, and infrared rays. However, when the phosphor is exposed to the excitation source as described above for a long time, there is a problem that the luminance of the phosphor decreases.

  Therefore, in recent years, ternary systems have been used in place of conventional phosphors such as silicate phosphors, phosphate phosphors, aluminate phosphors, borate phosphors, sulfide phosphors, and oxysulfide phosphors. Many new materials have been synthesized for the above nitrides. In recent years, phosphors having excellent characteristics have been developed particularly in multi-component nitrides and oxynitrides based on silicon nitride.

In Patent Document 1, the general formula M _x Si _y N _z : Eu [where M is at least one alkaline earth metal element selected from the group consisting of Ca, Sr, and Ba, and x, y , And z are numbers satisfying z = 2 / 3x + 4 / 3y. ] Are disclosed. These phosphors are synthesized by adding alkaline earth metal nitride by nitriding alkaline earth metal and adding silicon nitride to this, or using an alkaline earth metal and silicon imide as raw materials. It is synthesized by heating in a nitrogen or argon stream. In both cases, alkaline earth metal nitrides sensitive to air and moisture had to be used as raw materials, and there was a problem in industrial production.

Patent Document 2 discloses an oxynitride represented by the general formula M ₁₆ Si ₁₅ O ₆ N ₃₂ , a general formula MSiAl ₂ O ₃ N ₂ , M ₁₃ Si ₁₈ Al ₁₂ O ₁₈ N ₃₆ , MSi ₅ Al ₂ ON ₉ and An oxynitride phosphor having a sialon structure represented by M ₃ Si ₅ AlON ₁₀ is disclosed. In particular, when M is Sr, SrCO ₃ , AlN, and Si ₃ N ₄ are mixed at a ratio of 1: 2: 1 and heated in a reducing atmosphere (hydrogen-containing nitrogen atmosphere). As a result, SrSiAl ₂ O ₃ N ₂ : It is described that Eu ²⁺ was obtained.
In this case, the obtained phosphor is only an oxynitride phosphor, and no nitride phosphor containing no oxygen is obtained.

  In addition, since the nitride or oxynitride phosphor has a low reactivity of the raw material powder used, the contact area between the raw material powders for the purpose of promoting a solid-phase reaction between the raw material mixed powders during firing. It is necessary to heat with increasing the size. Therefore, these phosphors are synthesized in a compression molded state at a high temperature, that is, a very hard sintered body. Therefore, the sintered body obtained in this way needs to be pulverized to a fine powder suitable for the intended use of the phosphor. However, when a phosphor that is a hard sintered body is pulverized over a long period of time using a normal mechanical pulverization method such as a jaw crusher or a ball mill, There has been a problem that a large number of defects are generated and the emission intensity of the phosphor is significantly reduced.

In addition, it is said that alkaline earth metal nitrides such as calcium nitride (Ca ₃ N ₂ ) and strontium nitride (Sr ₃ N ₂ ) are preferably used in the production of nitride or oxynitride phosphors. In general, divalent metal nitrides easily react with moisture to form hydroxides, and are unstable in moisture-containing atmospheres. In particular, in the case of powder of Sr ₃ N ₂ or Sr metal, this tendency is remarkable and handling is very difficult.

  For these reasons, new phosphor materials and methods for producing the same have been demanded.

  In recent years, Patent Document 3 has been reported regarding a method for producing a nitride phosphor using a metal as a starting material. Patent Document 3 discloses an example of a method for producing an aluminum nitride phosphor, which describes that transition elements, rare earth elements, aluminum and alloys thereof can be used as raw materials. However, an example using an alloy as a raw material is not described, and it is characterized by using Al metal as an Al source. In addition, it differs from the present invention in that a combustion synthesis method is used to ignite the raw material and instantaneously raise the temperature to a high temperature (3000 K). That is, it is difficult to uniformly distribute the activation element by the method of instantaneously raising the temperature to 3000 K, and it is difficult to obtain a phosphor having high characteristics. Further, there is no description regarding a nitride phosphor containing an alkaline earth metal element obtained from an alloy raw material, and further a nitride phosphor containing silicon.

Special table 2003-515665 gazette JP 2003-206481 A JP 2005-54182 A

  An object of the present invention is to obtain a phosphor that emits yellow to orange, or orange to red when it is excited by light from the near ultraviolet region to the blue region and has high luminance and luminous efficiency.

As a result of intensive studies, the present inventors have found that a phosphor having a low peak in a specific range in the powder X-ray diffraction pattern has high luminance and luminous efficiency, and completed the present invention.
That is, the gist of the present invention is the following [1] to [ 14 ].

[2] A phosphor represented by the following general formula (2), wherein 2θ is 34 ° or more and 36.36 ° or less in a powder X-ray diffraction pattern measured using CuKα rays (1.54184Å). The peak of the impurity having the strongest peak in the range and appearing in the region 1-6 shown in the following <Table A> in addition to the crystal phase of the phosphor is the region 1 (10 in which 2θ is shown in the following <Table A>. The peak intensity ratio I of the peak existing in the range of not less than 17 ° and not more than 17 ° is less than 0.2% , and the peak intensity ratio I in the regions 2 to 6 is 8% or less. body.
However, the peak intensity ratio I corresponds to the peak Imax of the strongest peak existing in the range of 2θ between 34 ° and 36.36 ° in the powder X-ray diffraction pattern where 2θ is in the range of 10 ° to 60 °. The ratio of the height Ip (Ip × 100) / Imax (%). Here, the peak intensity is a value obtained by performing background correction.

M ^{1 ′} _{a ′} Sr _{b ′} Ca _{c ′} M ^{2 ′} _{d ′} Al _{e ′} Sif _′ N _{g ′} (2)
(However, a ′, b ′, c ′, d ′, e ′, f ′, g ′ are values in the following ranges, respectively.
0.00001 ≦ a ′ ≦ 0.15,
0.7 ≦ b ′ ≦ 0.99999,
0 ≦ c ′ <1,
0 ≦ d ′ <1,
a ′ + b ′ + c ′ + d ′ = 1,
0.5 ≦ e ′ ≦ 1.5,
0.5 ≦ f ′ ≦ 1.5,
2.5 ≦ g ′ ≦ 3.5
M ^{1 ′} represents Eu or an activation element composed of Eu and Ce, and M ^{2 ′} represents Mg and / or Ba. )

[2] emission peak wavelength above 590 nm, and wherein the at 650nm or less, the phosphor according to [1].

[ 3 ] The phosphor according to [1] or [ 2], wherein the oxygen content is 5% by weight or less.

[ 4 ] The crystal structure is orthorhombic, and the lattice constant is 9.75Å ≦ a ≦ 9.93Å, 5.69Å ≦ b ≦ 5.77Å, 5.1Å ≦ c ≦ 5.18Å, 280３ ³ ≦ V ≦ 298Å is ³ [1] to phosphor according to any one of [3].

[ 5 ] The phosphor according to any one of [1] to [ 4 ], wherein the internal quantum efficiency is 0.6 or more.

[ 6 ] A phosphor-containing composition comprising the phosphor according to any one of [1] to [ 5 ] and a liquid medium.

[ 7 ] A first light emitter and a second light emitter that emits visible light when irradiated with light from the first light emitter, and the second light emitter includes [1] to [ 5 ]. A light emitting device comprising at least one of the phosphors according to any one of the above as a first phosphor.

[8] The second luminous body, according to which the different at least one phosphor of the first peak emission wavelength and the phosphor, characterized in that it contains as the second phosphor [7] Light-emitting device.

[ 9 ] The first light emitter has a light emission peak in a wavelength range of 420 nm to 500 nm, and the second light emitter emits light in a wavelength range of 500 nm to 550 nm as the second phosphor. The light-emitting device according to [ 8 ], comprising at least one phosphor having a peak.

[ 10 ] The first light emitter has a light emission peak in a wavelength range of 300 nm to 420 nm, and the second light emitter emits light in a wavelength range of 420 nm to 490 nm as the second phosphor. The light-emitting device according to [ 8 ], comprising at least one phosphor having a peak and at least one phosphor having a light emission peak in a wavelength range of 500 nm to 550 nm.

[ 11 ] An image display device comprising the light-emitting device according to any one of [ 7 ] to [ 10 ].

[ 12 ] An illumination device comprising the light emitting device according to any one of [ 7 ] to [ 10 ].

The phosphor based on the nitride or oxynitride according to the present invention emits light with higher brightness than the conventional nitride or oxynitride phosphor, and is a yellow to orange or orange to red phosphor. As excellent. In addition, the phosphor of the present invention is a useful phosphor that is less likely to decrease in luminance even when exposed to an excitation source for a long time, and is suitably used for VFD, FED, PDP, CRT, white LED, and the like. is there. In addition, since the matrix color is red and absorbs ultraviolet rays, it is also suitable for red pigments and ultraviolet absorbers.
In addition, by using a composition containing this phosphor, a light emitting device with high luminous efficiency can be obtained. This light emitting device is suitably used for applications such as an image display device and a lighting device.

It is a typical perspective view which shows one Example of the light-emitting device of this invention. FIG. 2A is a schematic cross-sectional view showing an embodiment of a bullet-type light emitting device of the present invention, and FIG. 2B is a schematic view showing an embodiment of the surface-mounted light-emitting device of the present invention. It is sectional drawing. It is typical sectional drawing which shows one Example of the illuminating device of this invention. 3 is a chart showing a powder X-ray diffraction pattern of the phosphor of Example 1. FIG. It is a graph which shows the temperature characteristic of the fluorescent substance of Examples 1-3 and Reference Example 1. It is a graph which shows the brightness | luminance maintenance factor of the fluorescent substance of Examples 1-3 and Reference Example 1. It is a chart which shows the excitation spectrum of the fluorescent substance of Example 1 and Example 2. FIG. 6 is a chart showing a powder X-ray diffraction pattern of the phosphor of Comparative Example 1.

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 within the scope of the gist of the present invention.
In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Composition of phosphor]
Although there is no restriction | limiting in particular about the composition of the fluorescent substance which makes the nitride or oxynitride of this invention a base material, An example is given and demonstrated below.
In the present specification, the matrix of the phosphor means a crystal or glass (amorphous) capable of dissolving the activating element, and the crystal or glass (amorphous) itself does not contain the activating element. Including those that emit light.

The phosphor of the present invention contains at least a tetravalent metal element M ⁴ containing Si and one or more metal elements other than Si, and further contains an activating element M ¹ . Here, as a metal element other than Si, an alkaline earth metal element is preferable.
The phosphor of the present invention preferably includes an activating element M ¹ , a divalent metal element M ² , and a tetravalent metal element M ⁴ containing at least Si, and the activating element M ¹ , divalent metal element More preferably, M ² , a trivalent metal element M ³ , and a tetravalent metal element M ⁴ including at least Si are included.

As the activator element M ¹ , various light-emitting ions that can be contained in a crystal matrix constituting a phosphor having a nitride or oxynitride as a matrix can be used, but Cr, Mn, Fe, Ce, Pr It is preferable to use one or more elements selected from the group consisting of Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb because a phosphor with high emission characteristics can be produced. The activator element M ¹ preferably contains one or more of Mn, Ce, Pr and Eu, and particularly contains Ce and / or Eu to obtain a phosphor exhibiting high-luminance red light emission. More preferably. Moreover, in order to give various functions, such as raising a brightness | luminance and providing luminous property, as activator element M1, ¹ or more types of coactivators may be contained in addition to Ce and / or Eu. good.

The elements other than the activating element M ^1, 2-valent various trivalent, can be used tetravalent metal elements. Divalent metal elements ^{M 2} is Mg, Ca, at least one element selected Sr, Ba, and from the group consisting of Zn, consisting trivalent metal elements ^{M 3} is Al, Ga, In, and from Sc It is one or more elements selected from the group, and the tetravalent metal element M ⁴ is one or more elements selected from the group consisting of Si, Ge, Sn, Ti, Zr, and Hf. It is preferable because a phosphor having a high thickness can be obtained.

Also preferred since divalent and 50 mol% or more of the metal elements M ² to adjust the composition so that the Ca and / or Sr emission characteristics of high phosphor is obtained. Among them, more preferable to divalent least 80 mole percent of the metal element ^{M 2} and Ca and / or Sr, more preferably to at least 90 mol% Ca and / or Sr, a divalent metal element M Most preferably, all of ² are Ca and / or Sr.

Further, it is preferable to adjust the composition so that 50 mol% or more of the trivalent metal element M ³ is Al since a phosphor with high emission characteristics can be obtained. Among them, it is preferable to trivalent at least 80 mole percent of the metal element M ³ and Al, be more preferably set to Al more than 90 mol%, all trivalent metal elements M ³ Al Most preferred.

In addition, it is preferable to adjust the composition so that at least 50 mol% of the tetravalent metal element M ⁴ containing Si is Si because a phosphor with high emission characteristics can be obtained. Among these, at least 80 mol% of the tetravalent metal element M ⁴ containing Si is preferably Si, more preferably 90 mol% or more is Si, and all of the tetravalent metal element M ⁴ is Si. It is preferable that

In particular, a divalent metal elements ^{M 2} of 50 mol% or more Ca and / or Sr, and 50 mol% or more trivalent metal elements ^{M 3} is Al, and tetravalent containing at least Si It is preferable that 50 mol% or more of the metal element M ⁴ is Si because a phosphor having particularly high light emission characteristics can be manufactured.

Among them, the phosphor of the present invention preferably has a chemical composition represented by the following general formula [1].
_{^{M 1 a M 2 b M 3}} c M 4 d N e O f [1]
(However, a, b, c, d, e, and f are values in the following ranges, respectively.
0.00001 ≦ a ≦ 0.15
a + b = 1
0.5 ≦ c ≦ 1.5
0.5 ≦ d ≦ 1.5
2.5 ≦ e ≦ 3.5
0 ≦ f ≦ 0.5)
In the general formula [1], M ¹ represents the activation element M ¹ , M ² represents the divalent metal element M ² , M ³ represents the trivalent metal element M ³ , M ⁴ represents the tetravalent metal element M ⁴ containing at least Si.

  In addition, the reason why the numerical range of a to f in the general formula [1] is preferable is as follows.

  When a is smaller than 0.00001, sufficient light emission intensity tends to be not obtained, and when a is larger than 0.15, concentration quenching increases and the light emission intensity tends to decrease. Therefore, it is preferable to mix the raw materials so that a is in the range of 0.00001 ≦ a ≦ 0.15. For the same reason, 0.0001 ≦ a ≦ 0.1 is preferable, 0.001 ≦ a ≦ 0.05 is more preferable, 0.002 ≦ a ≦ 0.04 is further preferable, and 0.004 ≦ a ≦ 0. .02 is most preferable.

the sum of a and b, since the activator elements M ¹ replaces the divalent atomic position of the metal elements M ² in the crystal matrix of the phosphor to adjust the raw material mixed composition such that the normal 1.

  When c is smaller than 0.5 or when c is larger than 1.5, a heterogeneous phase is produced during production, and the yield of the phosphor tends to be low. Therefore, the raw materials are mixed so that c is in the range of 0.5 ≦ c ≦ 1.5. From the viewpoint of emission intensity, 0.5 ≦ c ≦ 1.5 is preferable, 0.6 ≦ c ≦ 1.4 is more preferable, and 0.8 ≦ c ≦ 1.2 is most preferable.

  Whether d is smaller than 0.5 or d is larger than 1.5, a heterogeneous phase is produced during production, and the yield of the phosphor tends to be low. Accordingly, the raw materials are mixed so that d is in the range of 0.5 ≦ d ≦ 1.5. From the viewpoint of light emission intensity, 0.5 ≦ d ≦ 1.5 is preferable, 0.6 ≦ d ≦ 1.4 is more preferable, and 0.8 ≦ d ≦ 1.2 is most preferable.

e is a coefficient indicating the nitrogen content;
It becomes. If 0.5 ≦ c ≦ 1.5 and 0.5 ≦ d ≦ 1.5 are substituted into this equation, the range of e is 1.84 ≦ e ≦ 4.17.
It becomes. However, in the phosphor composition represented by the general formula [1], the yield of the phosphor tends to decrease when e indicating the nitrogen content is less than 2.5. Even if e exceeds 3.5, the yield of the phosphor tends to decrease. Therefore, e is usually 2.5 ≦ e ≦ 3.5.

  The oxygen in the phosphor represented by the general formula [1] may be mixed as an impurity in the raw metal, or may be introduced during a manufacturing process such as a pulverization process or a nitriding process. The ratio of oxygen f is preferably in the range of 0 ≦ f ≦ 0.5 within a range in which a decrease in the light emission characteristics of the phosphor is acceptable.

Among the phosphors represented by the general formula [1], the phosphor represented by the following general formula [2] can be used.
M ^{1 ′} _{a ′} Sr _{b ′} Ca _{c ′} M ^{2 ′} _{d ′} Al _{e ′} Sif _′ N _{g ′} [2]
(However, a ′, b ′, c ′, d ′, e ′, f ′, and g ′ are values in the following ranges, respectively.
0.00001 ≦ a ′ ≦ 0.15
0.1 ≦ b ′ ≦ 0.99999
0 ≦ c ′ <1
0 ≦ d ′ <1
a ′ + b ′ + c ′ + d ′ = 1
0.5 ≦ e ′ ≦ 1.5
0.5 ≦ f ′ ≦ 1.5
0.8 × (2/3 + e ′ + 4/3 × f ′) ≦ g ′ ≦ 1.2 × (2/3 + e ′ + 4/3 × f ′))

Here, M ^{1 ′} is the group consisting of Cr, Mn, Fe, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb, similarly to M ¹ in the general formula [1]. Represents an activation element selected from Among them, the activator element M ^{1 ′} preferably includes one or more of Mn, Ce, Pr, and Eu, and particularly preferably includes Eu and / or Ce.

M ^{2 ′} represents Mg and / or Ba, and is preferably Mg. Inclusion of Mg can increase the emission peak wavelength of the phosphor.

  The range of a ′ is usually 0.00001 ≦ a ′ ≦ 0.15, preferably 0.001 ≦ a ′ ≦ 0.05, more preferably 0.002 ≦ a ′ ≦ 0.01.

  The range of b ′ is usually 0.1 ≦ b ′ ≦ 0.99999, preferably 0.4 ≦ b ′ ≦ 0.99999, and more preferably 0.7 ≦ b ′ ≦ 0.99999.

  The range of c ′ is usually 0 ≦ c ′ <1, preferably 0 ≦ c ′ ≦ 0.5, and more preferably 0 ≦ c ′ ≦ 0.3.

  The range of d ′ is usually 0 ≦ d ′ <1, preferably 0 ≦ d ′ ≦ 0.5, more preferably 0 ≦ d ′ ≦ 0.2.

The relationship between a ′, b ′, c ′, d ′ is usually
a ′ + b ′ + c ′ + d ′ = 1
Satisfied.

  The range of e ′ is usually 0.5 ≦ e ′ ≦ 1.5, preferably 0.8 ≦ e ′ ≦ 1.2, and more preferably 0.9 ≦ e ′ ≦ 1.1.

  The range of f ′ is usually 0.5 ≦ f ′ ≦ 1.5, preferably 0.8 ≦ f ′ ≦ 1.2, and more preferably 0.9 ≦ f ′ ≦ 1.1.

The range of g ′ is usually 0.8 (2/3 + e ′ + 4/3 × f ′) ≦ g ′ ≦ 1.2 × (2/3 + e ′ + 4/3 × f ′), preferably 0.9. × (2/3 + e ′ + 4/3 × f ′) ≦ g ′ ≦ 1.1 × (2/3 + e ′ + 4/3 × f ′), more preferably 2.5 ≦ g ′ ≦ 3.5. .

  Hereinafter, a phosphor in which the value of b ′ in the general formula [2] is in a range of 0.4 ≦ b ′ ≦ 0.99999 and d ′ = 0, that is, a phosphor having a large amount of Sr substitution. May be abbreviated as “SCASN phosphor”.

Oxygen contained in the phosphor of the present invention may be mixed as an impurity in the raw metal, or mixed during a manufacturing process such as a pulverization process or a nitriding process.
The oxygen content is usually 5% by weight or less, preferably 2% by weight or less, and most preferably 1% by weight or less as long as the reduction in the light emission characteristics of the phosphor is acceptable.

Specific examples of the composition of the phosphor include (Sr, Ca, Mg) AlSiN ₃ : Eu, (Sr, Ca, Mg) AlSiN ₃ : Ce, (Sr, Ca) ₂ Si ₅ N ₈ : Ce, and the like. .

[Phosphor production method]
The method for producing the phosphor of the present invention is not particularly limited, but a production method in which the impurities derived from the raw material are few and impurities are not mixed in the production process is preferable. Further, nitriding the raw material under high pressure tends to obtain a phosphor having high emission characteristics, which is more preferable. Specific examples include a production method using an alloy as a raw material (hereinafter sometimes referred to as “alloy method”) and a production method for obtaining a phosphor by nitriding a metal compound as a raw material under high pressure. Among them, it is preferable to use an alloy method because the obtained phosphor has more excellent light emission characteristics.

<Alloy method>
Hereinafter, a method for producing a phosphor by an alloy method will be described in detail.
In order to produce the phosphor of the present invention using the alloy method, for example, when producing a phosphor having the composition represented by the general formula [1], the composition of the following general formula [3] is obtained. Then, a metal as a raw material or an alloy thereof (hereinafter sometimes simply referred to as “raw metal”) is weighed. Next, this is melted and alloyed to produce a phosphor raw material alloy, and then the phosphor raw material alloy is pulverized to produce an alloy powder, which is then nitrided by heating in a nitrogen-containing atmosphere.

The alloy method will be described in more detail below. An alloy for a phosphor material containing a tetravalent metal element M ⁴ containing at least Si and at least one alkaline earth metal element as the divalent metal element M ² When melting the raw material metal as described later, after melting a high melting point (high boiling point) Si metal and / or an alloy containing Si, a low melting point (low boiling point) It is preferable to melt the alkaline earth metal.
M ¹ _a M ² _b M ³ _c M ⁴ _d [3]
(However, M ¹ , M ² , M ³ , M ⁴ , a, b, c, and d are respectively synonymous with those in the general formula [1].)

<Purity of raw metal>
The purity of the metal used for the production of the alloy is 0.1 mol% or less, preferably 0.01 mol% or less, as the metal raw material of the activation element M ¹ from the viewpoint of the light emission characteristics of the phosphor to be synthesized. It is preferable to use a metal that has been purified to a minimum. When using Eu as activator elements M ^1, it is preferable to use Eu metal as Eu raw material. As the raw material of the activator elements M ¹ other elements, divalent, trivalent, using a tetravalent various metals. For the same reason as activator elements M ^1, preferably both the concentration of impurities contained in more than 0.1 mol%, more preferably not more than 0.01 mol%. For example, when at least one selected from the group consisting of Fe, Ni, and Co is contained as an impurity, the content of each element is usually 500 ppm or less, preferably 100 ppm or less.

<Raw metal shape>
Although there is no restriction | limiting in the shape of a raw material metal, Usually, the thing of a granular form or a lump shape with a diameter of several mm to several dozen mm is used.
When using the divalent alkaline earth metal element as the metal element M ^2, as a raw material thereof, granular, but shapes such as bulk is not limited, it is preferable to select an appropriate shape depending on the chemical nature of the material. For example, Ca is stable in the atmosphere in either a granular form or a lump, and can be used. However, since Sr is chemically more active, it is preferable to use a lump raw material.

<Melting of raw metal>
The raw metal is weighed so as to have the desired composition and melted. Although there is no restriction | limiting in particular in the method of fuse | melting raw material metal, For example, a resistance heating method, an electron beam method, an arc melting method, a high frequency induction heating method etc. can be used. Examples of the crucible material that can be used during melting include alumina, calcia, graphite, and molybdenum.

In weighing the raw material metal, the metal element lost due to volatilization, reaction with the crucible material, or the like during melting may be preliminarily weighed and added as necessary.
Further, when the melting of the raw material metal, in particular, when producing the alloy for phosphor precursor containing an alkaline earth metal element as Si and divalent metal elements M ^2, because of the following problems, high melting point (high It is preferable to melt an alkaline earth metal having a low melting point (low boiling point) after melting a boiling point Si metal and / or an alloy containing Si.

  The melting point of Si is 1410 ° C., which is about the same as the boiling point of alkaline earth metals (for example, Ca has a boiling point of 1494 ° C., Sr has a boiling point of 1350 ° C., and Ba has a boiling point of 1537 ° C.). In particular, since the boiling point of Sr is lower than the melting point of Si, it is extremely difficult to simultaneously melt Sr and Si.

On the other hand, this problem can be solved by first melting the Si metal, preferably producing a master alloy, and then melting the alkaline earth metal.
Furthermore, by melting the alkaline earth metal after melting the Si metal in this way, the purity of the resulting alloy is improved, and the effect of significantly improving the properties of the phosphor made from it is also achieved. .

The melting method of the raw material metal in the present invention is not particularly limited, but is usually a resistance heating method, an electron beam method, an arc melting method, and a high frequency induction heating method (hereinafter sometimes referred to as “high frequency melting method”). Etc. can be used. Among them, it is preferable to use the arc melting method and the high frequency melting method, and it is particularly preferable to use the high frequency melting method in view of the manufacturing cost.
Hereinafter, the case of (1) arc melting method / electron beam method and (2) high frequency melting method will be described in more detail.

(1) In the case of arc melting method / electron beam melting method In the case of arc melting / electron beam melting, melting is performed according to the following procedure.
i) An Si metal or an alloy containing Si is melted by an electron beam or arc discharge.
ii) Next, the alkaline earth metal is melted by indirect heating to obtain an alloy containing Si and the alkaline earth metal.
Here, after the alkaline earth metal is dissolved in the molten metal containing Si, mixing may be promoted by heating and stirring with an electron beam or arc discharge.

(2) In the case of high-frequency melting method Since an alloy containing an alkaline earth metal element has high reactivity with oxygen, it must be melted in a vacuum or an inert gas, not in the atmosphere. Under such conditions, the high frequency melting method is usually preferred. However, Si is a semiconductor and is difficult to melt by induction heating using high frequency. For example, the resistivity of aluminum at 20 ° C. is 2.8 × 10 ⁻⁸ Ω · m, while the resistivity of polycrystalline Si for semiconductor is 10 ⁵ Ω · m or more. Since it is difficult to directly melt a material having such a large specific resistivity at a high frequency, generally, a conductive susceptor is used, and heat is transferred to Si by heat conduction or radiation to melt. The susceptor may be disk-shaped or tubular, but a crucible is preferably used. As the material of the susceptor, graphite, molybdenum, silicon carbide and the like are generally used. However, these are very expensive and have a problem that they easily react with an alkaline earth metal. On the other hand, crucibles (such as alumina and calcia) that can melt alkaline earth metals are insulators and are difficult to use as susceptors. Therefore, in preparing alkaline earth metal and Si metal in a crucible and melting at high frequency, using a known conductive crucible (such as graphite) as a susceptor, Si metal and alkaline earth metal It is difficult to melt at the same time. Therefore, this problem is solved by melting in the following order.
i) The Si metal is melted by indirect heating using a conductive crucible.
ii) Next, an alkaline earth metal is melted by using an insulating crucible to obtain an alloy containing Si and an alkaline earth metal element.

  The Si metal may be cooled between the steps i) and ii), or the alkaline earth metal may be continuously melted without being cooled. When performing continuously, a crucible coated with calcia, alumina or the like suitable for melting an alkaline earth metal in a conductive container can be used.

More specific steps are described as follows.
i) Si metal and metal M (for example, Al, Ga) are melted by indirect heating using a conductive crucible to obtain a conductive alloy (mother alloy).
ii) Next, after melting the mother alloy of i) using an alkaline earth metal resistant crucible, the alloy containing Si and the alkaline earth metal element is obtained by melting the alkaline earth metal at high frequency. obtain.

  As a specific method for melting the Si metal or the Si-containing master alloy first and then melting the alkaline earth metal, for example, the Si metal or Si-containing master alloy is first melted, and then the alkaline earth metal is melted there. And the like.

Further, Si can be alloyed with a metal M other than the divalent metal element M ² to impart conductivity. In this case, the melting point of the obtained alloy is preferably lower than that of Si. An alloy of Si and Al is particularly preferable because the melting point is around 1010 ° C. and the melting point is lower than the boiling point of the alkaline earth metal element.
When a mother alloy of Si and a metal M other than the divalent metal element M ² is used, the composition is not particularly limited, but the mother alloy preferably has conductivity. In this case, the mixing ratio (molar ratio) of Si and the metal M is such that the metal M is usually in the range of 0.01 or more and 5 or less when the number of moles of Si is 1. It is preferable to produce a mother alloy having a melting point lower than the boiling point of the metal group element.
In addition, Si metal can also be added to the master alloy containing Si.

In the present invention, other than melting the alkaline earth metal after melting the Si metal, there is no particular limitation on the melting time of the other raw metal, but usually a large amount or a high melting point Thaw first.
In order to disperse the activation element M ¹ uniformly and the addition amount of the activation element M ¹ is small, it is preferable to melt the raw material metal of the activation element M ¹ after melting the Si metal.

In the case of producing a phosphor raw material alloy represented by the above general formula [3], in which the tetravalent metal element M ⁴ containing at least Si is Si and containing at least Sr as the divalent metal element M ² , It is preferable to melt by the following procedure.
(1) preparing a mother alloy of Si and trivalent metal elements M ^3. At this time, preferably, Si and the trivalent metal element M ³ are alloyed at a Si: M ³ ratio in the general formula [3].
(2) After melting the master alloy of (1), melt Sr.
(3) Thereafter, the divalent metal elements other than Sr, to melt the activator elements M ^1.

  As an atmosphere at the time of melting such a raw material metal, an inert atmosphere is preferable, and Ar is particularly preferable.

Moreover, the pressure is usually preferably in the range of 1 × 10 ³ Pa or more and 1 × 10 ⁵ Pa or less, and from the viewpoint of safety, it is desirable to carry out at atmospheric pressure or less.

<Casting of molten metal>
Nitrogen-containing alloys can be produced directly from the molten alloy produced by melting the raw metal, but after the casting process in which the molten alloy produced by melting the raw metal is poured into a mold and molded, the solidified body ( It is preferable to obtain an alloy lump. However, in this casting process, segregation occurs due to the cooling rate of the molten metal, and a composition that has a uniform composition in the molten state may have an uneven composition distribution. Therefore, it is desirable that the cooling rate be as fast as possible. The mold is preferably made of a material having good thermal conductivity such as copper, and preferably has a shape in which heat is easily dissipated. It is also preferable to devise cooling the mold by means such as water cooling if necessary.

  By such a device, for example, it is preferable to use a mold having a large bottom area with respect to the thickness and solidify as soon as possible after pouring the molten metal into the mold.

  Also, since the degree of segregation varies depending on the composition of the alloy, it is necessary to prevent segregation by collecting samples from several places of the obtained solidified body by using necessary analytical means such as ICP emission spectroscopy. It is preferable to set a proper cooling rate.

  The casting atmosphere is preferably an inert atmosphere, and Ar is particularly preferable.

<Ingot crushing>
The alloy lump obtained in the casting process is then pulverized to prepare an alloy powder having a desired particle size and particle size distribution. As the pulverization method, a dry method or a wet method using an organic solvent such as ethylene glycol, hexane, or acetone can be used. Hereinafter, the dry method will be described in detail as an example.
This pulverization step may be divided into a plurality of steps such as a coarse pulverization step, a medium pulverization step, and a fine pulverization step as necessary. In this case, the entire pulverization process can be pulverized using the same apparatus, but the apparatus used may be changed depending on the process.

  Here, the coarse pulverization step is a step of pulverizing so that approximately 90% by weight of the alloy powder has a particle size of 1 cm or less. Can be used. The middle pulverization step is a step of pulverizing so that approximately 90% by weight of the alloy powder has a particle size of 1 mm or less, and a pulverizer such as a cone crusher, a crushing roll, a hammer mill, or a disk mill can be used. . The fine pulverization step is a step of pulverizing the alloy powder so as to have a weight median diameter, which will be described later. Can be used.

  Among these, from the viewpoint of preventing impurities from being mixed, it is preferable to use a jet mill in the final pulverization step. In order to use a jet mill, the alloy lump is preferably pulverized in advance until the particle size is about 2 mm or less. In the jet mill, the particles are pulverized mainly by using the expansion energy of the fluid injected from the nozzle original pressure to the atmospheric pressure. Therefore, the particle size can be controlled by the pulverization pressure, and contamination of impurities can be prevented. Is possible. Although the pulverization pressure varies depending on the apparatus, it is usually in the range of 0.01 MPa or more and 2 MPa or less in gauge pressure. Among them, 0.05 MPa or more and less than 0.4 MPa is preferable, and 0.1 MPa or more and 0.3 MPa or less. Is more preferable.

  In any case, it is necessary to appropriately select the relationship between the material of the pulverizer and the object to be crushed so that impurities such as iron do not enter during the pulverization process. For example, the contact portion is preferably provided with a ceramic lining, and among ceramics, alumina, silicon nitride, tungsten carbide, zirconia and the like are preferable.

In order to prevent oxidation of the alloy powder, the pulverization step is preferably performed in an inert gas atmosphere, and the oxygen concentration in the inert gas atmosphere is preferably 10% or less, particularly preferably 5% or less. Moreover, as a minimum of oxygen concentration, it is about 10 ppm normally. By setting the oxygen concentration within a specific range, it is considered that an oxide film is formed on the surface of the alloy during pulverization and stabilized. When the pulverization step is performed in an atmosphere having an oxygen concentration higher than 5%, dust may explode during the pulverization, and thus equipment that does not generate dust is necessary. Although there is no restriction | limiting in particular in the kind of inert gas, Usually, 1 type single atmosphere or 2 or more types mixed atmosphere is used among gases, such as nitrogen, argon, and helium, and nitrogen is especially preferable from a viewpoint of economical efficiency.
Moreover, you may cool as needed so that the temperature of an alloy powder may not rise during a grinding | pulverization.

<Classification of alloy powder>
The alloy powder pulverized in the pulverization process is divided into a desired weight median described later using a sieve using a mesh such as a vibratory screen and a shifter, an inertia classifier such as an air separator, and a centrifuge such as a cyclone. It is adjusted to the diameter _{D 50} and particle size distribution.
In adjusting the particle size distribution, the coarse particles are preferably classified and recycled to a pulverizer, and the classification and / or recycling is more preferably continuous.

  This classification step is also preferably performed in an inert gas atmosphere, and the oxygen concentration in the inert gas atmosphere is preferably 10% or less, particularly preferably 5% or less. Although there is no restriction | limiting in particular in the kind of inert gas, Usually, 1 type single atmospheres, such as nitrogen, argon, helium, or 2 or more types of mixed atmospheres are used, and nitrogen is especially preferable from a viewpoint of economical efficiency.

The alloy powder before the primary nitriding process described later needs to adjust the particle size according to the activity of the metal element constituting the alloy powder, and the weight median diameter D ₅₀ is usually 100 μm or less, preferably 80 μm. Hereinafter, it is particularly preferably 60 μm or less, 0.1 μm or more, preferably 0.5 μm or more, particularly preferably 1 μm or more. In the case of containing Sr has a high reactivity with the ambient gas, the weight median diameter D ₅₀ of the alloy powder, usually 5μm or more, preferably 8μm or more, and more preferably 10μm or more, particularly preferably 13μm or more It is desirable to do. If the weight median diameter D ₅₀ is smaller than the above range, the rate of heat generation during a reaction such as nitriding increases, which may make it difficult to control the reaction. On the other hand, when the weight median diameter D ₅₀ is larger than the above range, the reaction such as nitriding inside the alloy particles may be insufficient.

<Manufacture of phosphor>
There is no particular limitation on the method for producing the phosphor using the above alloy powder, and reaction conditions are set according to the type of phosphor such as nitride, oxynitride, etc. explain.

For example, the nitriding treatment of the alloy powder is performed as follows.
That is, first, an alloy powder as a nitriding raw material is filled in a crucible or a tray. Examples of the material of the crucible or tray used here include boron nitride, silicon nitride, aluminum nitride, molybdenum, and tungsten. Boron nitride is preferable because of its excellent corrosion resistance.

  After putting the crucible or tray filled with the alloy powder into a heating furnace capable of controlling the atmosphere, a gas containing nitrogen is circulated to sufficiently replace the inside of the system with the nitrogen-containing gas. If necessary, a nitrogen-containing gas may be circulated after the system is evacuated.

  Examples of the nitrogen-containing gas used in the nitriding treatment include a gas containing nitrogen, such as nitrogen, ammonia, or a mixed gas of nitrogen and hydrogen. The oxygen concentration in the system affects the oxygen content of the phosphor to be produced, and if the content is too high, high light emission cannot be obtained. Therefore, the oxygen concentration in the nitriding atmosphere is preferably as low as possible, usually 1000 ppm or less, Preferably it is 100 ppm or less, More preferably, it is 10 ppm or less. Further, if necessary, an oxygen getter such as carbon or molybdenum may be placed in the in-system heating portion to lower the oxygen concentration.

  The nitriding treatment is performed by heating in a state filled with or containing a nitrogen-containing gas, but the pressure may be any of a reduced pressure, an atmospheric pressure or a pressurized pressure rather than atmospheric pressure. In order to prevent oxygen from being mixed in the atmosphere, the pressure is preferably set to atmospheric pressure or higher. If the pressure is less than atmospheric pressure, a large amount of oxygen may be mixed if the heating furnace is poorly sealed, and the properties of the resulting phosphor may be degraded. The pressure of the nitrogen-containing gas is preferably at least 0.2 MPa as a gauge pressure, and most preferably from 10 MPa to 200 MPa.

  The heating of the alloy powder is usually performed at a temperature of 800 ° C. or higher, preferably 1000 ° C. or higher, more preferably 1200 ° C. or higher, and usually 2200 ° C. or lower, preferably 2100 ° C. or lower, more preferably 2000 ° C. or lower. When the heating temperature is lower than 800 ° C., the time required for nitriding tends to be long. On the other hand, if the heating temperature is higher than 2200 ° C., the generated nitride is volatilized or decomposed, and the chemical composition of the obtained nitride phosphor shifts, and a phosphor with high characteristics cannot be obtained, or the reproducibility is poor. There is a case.

  The heating time (holding time at the maximum temperature) during the nitriding treatment may be a time required for the reaction between the alloy powder and nitrogen, but is usually 1 minute or more, preferably 10 minutes or more, more preferably 30 minutes or more, Preferably it is 60 minutes or more. If the heating time is shorter than 1 minute, the nitriding reaction does not proceed sufficiently and a phosphor having high characteristics may not be obtained. The upper limit of the heating time is usually preferably 24 hours or less from the viewpoint of production efficiency.

  After the nitriding treatment of the alloy, the obtained phosphor is preferably pulverized and classified. For example, it is particularly preferable to perform pulverization and classification so that 90% or more of the obtained phosphor particles become particles of 5 μm or more and 20 μm or less.

  In addition, as a method for producing the phosphor of the present invention, the above-described alloy method is most preferable because the obtained phosphor has more excellent light emission characteristics, but the method is not limited to the alloy method. The phosphor of the present invention can also be produced using a method in which a metal compound (preferably a metal nitride) is used as a raw material and nitriding is performed by heating under high pressure in a nitrogen-containing atmosphere. . Moreover, it is considered that the phosphor of the present invention can also be produced by a method using an imide compound or an amide compound having one or more elements constituting the phosphor as a raw material.

[Characteristics of phosphor]
(Crystal structure)
The crystal structure of the phosphor of the present invention will be described.
The crystal structure of the phosphor of the present invention preferably has the same orthorhombic (Cmc2 ₁ , # 36) crystal structure as the CASN structure described in WO2005 / 052087. The lattice constants are usually 9.7Å ≦ a ≦ 9.93Å, 5.6Å ≦ b ≦ 5.8Å, 5.0Å ≦ c ≦ 5.2Å, 270Å ³ ≦ V ≦ 300Å ³ , and more preferably 9 .75Å ≦ a ≦ 9.93Å, 5.69Å ≦ b ≦ 5.77Å, 5.1Å ≦ c ≦ 5.18Å, 280Å ³ ≦ V ≦ 298Å ³ .

(Powder X-ray diffraction pattern)
The present inventors examined a powder X-ray diffraction pattern measured when CuKα rays (1.54184１．５) were used for the phosphor of the present invention.

The phosphor of the present invention has the strongest peak in the range of 2θ between 34 ° and 36.7 ° in the powder X-ray diffraction pattern measured using CuKα ray (1.54184Å), and 2θ is 10 °. The peak intensity ratio I of the peak existing in the range of 17 ° or less (that means region 1 in Table A) is usually 4% or less, preferably 2% or less, more preferably 1% or less. It is characterized by being. However, the peak intensity ratio I corresponds to the height I _max of the strongest peak existing in the range of 2θ of 34 ° to 36.7 ° in the powder X-ray diffraction pattern of 2θ of 10 ° to 60 °. The ratio of the peak height I _p is (I _p × 100) / I _max (%). Here, the peak intensity is a value obtained by performing background correction.

  In addition to the above, the phosphor of the present invention has a peak intensity ratio I in regions 2 to 6 shown in the following <Table A> in a powder X-ray diffraction pattern measured using CuKα rays (1.54184Å). Usually, it is preferably 10% or less, preferably 8% or less, more preferably 3% or less.

  Examples of powder X-ray diffraction patterns are shown in Table B below. In Table B, the X-ray powder diffraction peak position is represented by 2θ (within a range of 10 ° to 60 °).

When the phosphor of the present invention has the chemical composition represented by the general formula [1], the amount of Sr and Ca that can be contained can be changed. In Table B, the amount of Ca is decreased and the amount of Sr is increased in the order of Example 1, Example 2, Example 3, Example 4, and Example 5. Examples 1 to 5 described in Table B are orthorhombic crystals of the same type as CASN, and show several peaks below the strongest peak.
From Table B, it can be seen that the diffraction peak position shifts depending on the substitution amount of Sr. Since Sr has a larger ionic radius than Ca, the larger the Sr substitution amount, the larger the lattice constant and the smaller the 2θ value at the peak position.

The peak position in the powder X-ray diffraction pattern derived from the same crystal structure as the CaAlSiN ₃ crystal of the phosphor of the present invention is usually a position where Example 5 is the lower limit and Example 1 is the upper limit, and preferably This is a position where 4 is the lower limit and Example 2 is the upper limit. Furthermore, the peak position in Example 3 is preferably within the range of ± 0.2 °.

  The phosphor of the present invention usually has 7 or more, preferably 10 or more of the peaks shown in Table B.

(Emission spectrum)
For example, the phosphor of the present invention has a chemical composition represented by the general formula [2], and, if it contains Eu as activator elements M ^1, in view of the use as an orange or red phosphor When the emission spectrum is measured when excited with light having a peak wavelength of 465 nm, it preferably has the following characteristics.

  First, the above-mentioned phosphor preferably has a peak wavelength λp (nm) in the above-mentioned emission spectrum that is usually larger than 590 nm, particularly 600 nm or more, and usually 650 nm or less, especially 640 nm or less. If the emission peak wavelength λp is too short, it tends to be yellowish, whereas if it is too long, it tends to be dark reddish, which is not preferable because the characteristics as orange or red light may be deteriorated.

  Further, the above phosphor has a full width at half maximum (hereinafter, abbreviated as “FWHM” where appropriate) in the above-mentioned emission spectrum, which is usually larger than 50 nm, particularly 70 nm or more, and more preferably 75 nm or more. In addition, it is usually preferably less than 120 nm, more preferably 100 nm or less, and even more preferably 90 nm or less. If the full width at half maximum FWHM is too narrow, the emission intensity may decrease, and if it is too wide, the color purity may decrease.

  In order to excite the phosphor with light having a peak wavelength of 465 nm, for example, a GaN-based light emitting diode can be used. The emission spectrum of the phosphor of the present invention can be measured by, for example, a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a 150 W xenon lamp as an excitation light source and a multichannel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus. ) Or the like. The emission peak wavelength and the half width of the emission peak can be calculated from the obtained emission spectrum.

(Weight median diameter D ₅₀ )
The phosphor of the present invention preferably has a weight median diameter D ₅₀ in the range of usually 3 μm or more, especially 5 μm or more, and usually 30 μm or less, especially 20 μm or less. When the weight-average median diameter D ₅₀ is too small, and if the luminance is lowered, there is a case where phosphor particles tend to aggregate. On the other hand, when the weight-average median diameter D ₅₀ is too large, there is a tendency for blockage, such as uneven coating or a dispenser.
The weight-average median diameter D ₅₀ of the phosphor in the present invention, for example, can be measured using a device such as a laser diffraction / scattering particle size distribution measuring apparatus.

(Temperature characteristics)
The phosphor of the present invention also has excellent temperature characteristics. Specifically, the ratio of the emission peak intensity value in the emission spectrum diagram at 150 ° C. to the emission peak intensity value in the emission spectrum diagram at 25 ° C. when light having a peak at a wavelength of 455 nm is normally 55 % Or more, preferably 60% or more, particularly preferably 70% or more.
Further, since the emission intensity of ordinary phosphors decreases with increasing temperature, it is unlikely that the ratio exceeds 100%, but it may exceed 100% for some reason. However, if it exceeds 150%, the color shift tends to occur due to a temperature change.

  The phosphor of the present invention is excellent in temperature characteristics not only with respect to the emission peak intensity but also in terms of luminance. Specifically, the ratio of the luminance at 150 ° C. to the luminance at 25 ° C. when irradiated with light having a peak at a wavelength of 455 nm is usually 55% or more, preferably 60% or more, particularly preferably 70%. That's it.

  When measuring the temperature characteristics, for example, an MCPD7000 multi-channel spectrum measuring device manufactured by Otsuka Electronics as an emission spectrum device, a color luminance meter BM5A as a luminance measuring device, a cooling mechanism using a Peltier element, and a heating mechanism using a heater. And it can measure as follows using the apparatus provided with a 150W xenon lamp as a light source. A cell containing a phosphor sample is placed on the stage, and the temperature is changed in the range of 20 ° C to 150 ° C. Confirm that the surface temperature of the phosphor is constant at the measurement temperature. Next, the emission spectrum is measured by exciting the phosphor with light having a peak wavelength of 455 nm extracted from the light source by spectroscopy with a diffraction grating. The emission peak intensity is obtained from the measured emission spectrum. Here, as the measured value of the surface temperature on the excitation light irradiation side of the phosphor, a value corrected using the measured temperature value by the radiation thermometer and the thermocouple is used.

(Other)
The phosphor of the present invention is more preferable as its internal quantum efficiency is higher. The value is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more. If the internal quantum efficiency is low, the light emission efficiency tends to decrease, which is not preferable.

  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 0.7 or more. If the absorption efficiency is low, the light emission efficiency tends to decrease, which is not preferable.

[Use of phosphor]
The phosphor of the present invention can be suitably used for various light-emitting devices (hereinafter referred to as “light-emitting device of the present invention”) by taking advantage of its high luminance and high color rendering properties. For example, when the phosphor of the present invention is an orange or red phosphor, a white light emitting device with high color rendering can be realized by combining a green phosphor and a blue phosphor. 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. The phosphor of the present invention can be used alone. For example, an orange light emitting device can be manufactured by combining a near ultraviolet LED and the orange phosphor of the present invention.

[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.

<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, you may make the fluorescent substance containing composition of this invention contain fluorescent substances other than the fluorescent substance of this invention as needed.

<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 in the target 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.

  As the inorganic material, for example, a solution obtained by hydrolytic polymerization of a solution containing a metal alkoxide, a ceramic precursor polymer or a metal alkoxide by a sol-gel method, or a combination thereof, an inorganic material (for example, a siloxane bond) Inorganic materials having

  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, when using a phosphor for a high-power light-emitting device such as illumination, it is preferable to use a silicon-containing compound 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 following formula (i) and / or a mixture thereof.

In the above formula (i), R ¹ to R ⁶ may be the same or different and are selected from the group consisting of an organic functional group, a hydroxyl group, and a hydrogen atom.
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 the silicone material is used for sealing a semiconductor light emitting device that can be used as a first light emitter described later, the silicone material is sealed with a liquid silicone material and then cured by heat or light. Can do.

  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 a polyorganosiloxane chain is crosslinked by an organic addition bond. A typical example is a compound having a Si—C—C—Si bond at a 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 include polycondensates obtained by hydrolysis and polycondensation of compounds represented by the following general formula (ii) and / or (iii) and / or oligomers thereof.

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

^{_{M s + X t Y 1 s}} -t (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.

  As such a condensation type silicone material, for example, semiconductor light emitting device members described in Japanese Patent Application Nos. 2006-47274 to 47277 and Japanese Patent Application No. 2006-176468 are suitable.

Of the condensed silicone materials, particularly preferred materials will be described below.
Silicone materials generally have a problem of poor adhesion to semiconductor light emitting elements, substrates on which elements are arranged, packages, and the like, but as silicone 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.

<Characteristic [1] (silicon content)>
The basic skeleton of the conventional silicone-based material is an organic resin such as an epoxy resin having carbon-carbon and carbon-oxygen bonds as the basic skeleton, whereas the basic skeleton of the silicone-based material of the present invention is glass (silicate). It is the same inorganic siloxane bond as glass). As is apparent from the chemical bond comparison table shown in Table 5 below, this siloxane bond has the following characteristics excellent as a silicone material.

(I) Since the binding energy is large and thermal decomposition and photolysis are difficult, light resistance is good.
(II) It is slightly polarized electrically.
(III) The degree of freedom of the chain structure is large, a structure with high flexibility is possible, and the chain structure can freely rotate around the center of the siloxane chain.
(IV) The degree of oxidation is large and no further oxidation occurs.
(V) Rich in electrical insulation.

  Because of these characteristics, silicone-based silicone materials that are formed with a skeleton in which siloxane bonds are three-dimensionally bonded with a high degree of crosslinking are close to inorganic materials such as glass or rock, and have a high heat resistance and light resistance. Can be understood. In particular, a silicone-based material having a methyl group as a substituent has no absorption in the ultraviolet region, so that photolysis hardly occurs and has excellent light resistance.

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 4 because the silicon content of the glass composed solely of SiO ₂ is 47% by weight.
The range is 7% by weight or less.

  The silicon content of the silicone material is calculated based on the result of inductively coupled plasma spectrometry (hereinafter abbreviated as “ICP” where appropriate) using, for example, 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.

<Characteristic [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: Chemagnetics InfinityCMX-400 nuclear magnetic resonance spectrometer 29Si 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 1H decoupling frequency: 50 kHz
29Si flip angle: 90 ° 29Si90 ° 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.
The peak is identified by AIChE Journal, 44 (5), p. Refer to 1141, 1998, etc.

<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.

  In addition, the silanol content rate of a silicone type material uses the method demonstrated in the term of {the solid-state Si-NMR spectrum measurement and calculation of silanol content rate} of <characteristic [2] (solid Si-NMR spectrum)>, for example. The solid Si-NMR spectrum measurement is performed, and the ratio (%) of silicon atoms that are silanols in all silicon atoms is obtained from the ratio of the peak area derived from silanol to the total peak area, and compared with the silicon content analyzed separately. This can be calculated.

  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.

<Content of liquid medium>
The content of the liquid medium of the phosphor-containing composition of the present invention is arbitrary as long as the effects of the present invention are not significantly impaired, but usually 50% by weight or more, preferably with respect to the entire phosphor-containing composition of the present invention. Is 75% by weight or more, usually 99% by weight or less, preferably 95% by weight or less. When the amount of the liquid medium is large, no particular problem occurs. However, in order to obtain the desired chromaticity coordinates, color rendering index, luminous efficiency, etc. in the case of a light emitting device, the liquid is usually mixed at the above blending ratio. It is desirable to use a 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 serves 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.

<Other ingredients>
In addition, you may make the fluorescent substance containing composition of this invention contain other components other than a fluorescent substance and a liquid medium, unless the effect of this invention is impaired remarkably. 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.

[Light emitting device]
Next, the light emitting device of the present invention will be described.
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. The second light emitter contains one or more of the phosphors of the present invention described above as the first phosphor.

The phosphor of the present invention used in the light emitting device of the present invention is not particularly limited in its composition and emission color as long as it is the phosphor of the present invention described above. For example, the phosphor of the present invention is represented by the general formula [2], and, if it contains Eu as activator elements M ^1, the phosphor of the present invention is usually irradiated with light from the excitation light source Below, the phosphor emits fluorescence in the orange or red region (hereinafter sometimes referred to as “the orange or red phosphor of the present invention”). Specifically, when the phosphor of the present invention is an orange or red phosphor, those having an emission peak in a wavelength range of 590 nm to 640 nm are preferable. 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.

Further, the weight median diameter D ₅₀ of the phosphor of the present invention used in the light emitting device of the present invention is preferably in the range of usually 10 μm or more, particularly 15 μm or more, and usually 30 μm or less, especially 20 μm or less. When the weight-average median diameter D ₅₀ is too small, and the luminance decreases tends to phosphor particles tend to aggregate. On the other hand, if too large weight-average median diameter D _50, tends to blockage such as uneven coating or a dispenser.

  Further, preferred specific examples of the phosphor of the present invention used in the light emitting device of the present invention include the phosphor of the present invention described in the above-mentioned [Phosphor composition] column and the below-mentioned [Example] column. The phosphor used in each of the examples.

  The light-emitting device of the present invention has a first light emitter (excitation light source), and at least the phosphor of the present invention is used as the second light emitter. It is possible to arbitrarily adopt the apparatus configuration. A specific example of the device configuration will be described later.

  As the light emission peak in the orange to red region in the light emission spectrum of the light emitting device of the present invention, one having a light emission peak in the wavelength range of 590 nm to 670 nm is preferable.

  Among the light emitting devices of the present invention, in particular, as a white light emitting device, specifically, an excitation light source as described later is used as the first light emitter, and in addition to the orange or red phosphor as described above, as described later. A phosphor that emits green fluorescence (hereinafter referred to as “green phosphor” as appropriate), a phosphor that emits blue fluorescence (hereinafter referred to as “blue phosphor” as appropriate), and a phosphor that emits yellow fluorescence (hereinafter referred to as “ It can be obtained by using known phosphors such as “yellow phosphor” in any combination and using a known apparatus configuration.

  Here, the white color of the white light emitting device includes all of (yellowish) white, (greenish) white, (blueish) white, (purple) white, and white defined by JISZ8701. Of these, white is preferred.

<Configuration of light-emitting device (light-emitting body)>
(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 using near-ultraviolet light as excitation light, it is desirable to use an illuminant having an emission peak wavelength of usually 300 nm or more, preferably 330 nm or more, more preferably 360 nm or more, and usually 420 nm or less. When blue light is used as excitation light, it is desirable to use a light emitter having an emission peak wavelength of usually 420 nm or more, preferably 430 nm or more, and 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”) 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 output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely low power and extremely low power when combined with the phosphor of the present invention. This is because bright 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. In the GaN-based LED, the one having _{an In} X Ga _Y N emission layer Among these particularly preferred because the emission intensity is very strong, the GaN-based LED is _In X Ga _Y N layer and the multiple quantum well structure of GaN layer Is particularly preferable because the emission intensity is very strong.

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

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

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

Used for the in the second luminescent material is not particularly limited to the phosphor composition other than the phosphor of the present invention, the crystal _{matrix, Y 2 O 3, YVO 4} , Zn 2 SiO 4, Y 3 Metal oxides typified by Al ₅ O ₁₂ , Sr ₂ SiO ₄ , metal nitrides typified by Sr ₂ Si ₅ N ₈ , phosphates typified by Ca ₅ (PO ₄ ) ₃ Cl, etc. Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, sulfide represented by ZnS, SrS, CaS, etc., oxysulfide represented by Y ₂ O ₂ S, La ₂ O ₂ S, etc. A combination of rare earth metal ions such as Ho, Er, Tm, and Yb, and metal ions such as Ag, Cu, Au, Al, Mn, and Sb as activators or coactivators.

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 Aluminate 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, g) ₁₀ (PO ₄₎ such as ₆ Cl _{2 halophosphate;} Sr ₂ P _{2 O 7,} can be cited (La, Ce) phosphate PO _4, etc. and the like.

  However, the crystal matrix and the activator element or 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, the phosphor of the present invention, the represented by the general formula [2], and, in the case of containing Eu as activator elements M ^1, usually, since the phosphor of the present invention is a orange or red phosphor As the first phosphor, another type of orange or red phosphor can be used in combination with the phosphor of the present invention.

Any orange or red phosphor may be used as long as the effects of the present invention are not significantly impaired.
At this time, the emission peak wavelength of the orange to red phosphor, which is the same color combination phosphor, is usually 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. It is preferable to be in the following wavelength range.

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

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

In addition, examples of 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, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Ce activated oxide such as Ce , Nitride or oxynitride phosphor, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn activated halophosphate phosphor such as Eu, Mn, Ba ₃ MgSi ₂ O ₈ : Eu, Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu Eu, Mn activated silicate phosphor such as Mn, Mn, etc., 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn activated germanate phosphor such as Mn, Eu activated oxynitride such as Eu activated α sialon Phosphor, (Gd, Y, Lu, La) ₂ O ₃ : Eu, Bi activated oxide phosphor such as Eu, Bi, (Gd, Y, Lu, La) ₂ O ₂ S: Eu, Bi, etc. Eu, Bi-activated oxysulfide phosphors, (Gd, Y, Lu, La) VO ₄ : Eu, Bi-activated vanadate phosphors, SrY ₂ S ₄ : Eu, Ce, etc. Eu, Ce activated sulfide phosphor, Ce activated sulfide phosphor such as CaLa ₂ S ₄ : Ce, (Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba, Mg) _{, Zn) 2 P 2 O 7} : Eu, Eu such as Mn, Mn-activated phosphate phosphor, (Y, _{Lu) 2} O _6: Eu, Eu such as Mo, Mo-activated tungstate _{phosphor, (Ba, Sr, Ca)} x Si y N z: Eu, Ce ( provided that, x, y, z are an integer of 1 or more Represent. 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 red phosphors, (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, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu, It is preferable to contain (La, Y) ₂ O ₂ S: Eu or 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, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Sr, Ba) ₃ SiO _{5: Eu, (Ca, Sr} ) S: Eu or _{(La, Y) 2 O 2} S: Eu, or Eu ( Preferably comprises a _{dibenzoylmethane)} 3 · 1,10-beta-diketone Eu complex or carboxylic acid Eu complex phenanthroline complex, _{etc., (Ca, Sr, Ba)} 2 Si 5 (N, O) 8: Eu (Sr, Ca) AlSiN 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.
Any one of the orange to red phosphors exemplified above may be used alone, or two or more may be used in any combination and 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 an orange or red phosphor is used as the first phosphor, examples of the second phosphor include a first phosphor such as a green phosphor, a blue phosphor, and a yellow phosphor. Use phosphors that emit different colors.

The weight median diameter of the second phosphor used in the light emitting device of the present invention is usually in the range of 10 μm or more, especially 12 μm or more, and usually 30 μm or less, especially 25 μm or less. When the weight-average median diameter D ₅₀ is too small, and the luminance decreases tends to phosphor particles tend to aggregate. On the other hand, if too large weight-average median diameter D _50, tends to blockage such as uneven coating or a dispenser.

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

Such a blue phosphor is composed of grown particles having a substantially hexagonal shape as a regular crystal growth shape, and is represented by (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu that emits light in a blue region. Europium activated barium magnesium aluminate-based phosphor, composed of growing particles having a substantially spherical shape as a regular crystal growth shape, emits light in the blue region (Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ ( Cl, F): a europium-activated calcium halophosphate phosphor represented by Eu, and composed of grown particles having a substantially cubic shape as a regular crystal growth shape, and emits light in a blue region (Ca, Sr, Ba) ₂ A europium-activated alkaline earth chloroborate-based phosphor represented by B ₅ O ₉ Cl: Eu, comprising fractured particles having a fracture surface 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 phosphor such as Sb, Sb, BaAl ₂ Si ₂ O ₈ : Eu, (Sr, Ba) ₃ MgSi ₂ O ₈ : Eu-activated silicate phosphor such as Eu, Sr ₂ P ₂ O ₇ : Eu-activated phosphate phosphors such as Eu, sulfide phosphors such as ZnS: Ag, ZnS: Ag, Al, Ce-activated silicate phosphors such as Y ₂ SiO ₅ : Ce, tungsten such as CaWO _{4 phosphors, (Ba, Sr, Ca)} BPO 5: Eu, Mn, (Sr, Ca) 10 (PO 4) 6 · nB 2 O 3: Eu, 2SrO · 0.84P 2 O 5 · 0.16B ₂ O ₃ : Eu, Mn activated borate phosphate phosphor such as Eu, Sr ₂ Si ₃ O ₈ · 2SrCl ₂ : Eu activated halosilicate phosphor such as Eu, SrSi ₉ Al ₁₉ ON ₃₁ : Eu, EuSi ₉ Al ₁₉ Eu-activated of ON _31, etc. Nitride _{phosphor, La 1-x Ce x Al} (Si 6-z Al z) (N 10-z O z) ( here, x, and y are each 0 ≦ x ≦ 1,0 ≦ z ≦ 6 is a number _{satisfying.), La 1-x-} y Ce x Ca y Al (Si 6-z Al z) (N 10-z O z) ( here, x, y, and z are each 0 It is also possible to use Ce-activated oxynitride phosphors such as ≦ x ≦ 1, 0 ≦ y ≦ 1, and 0 ≦ z ≦ 6.

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

Among the above examples, as the blue phosphor, (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu or It is preferable to contain (Ba, Ca, Mg, Sr) ₂ SiO ₄ : Eu, and (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (PO Cl, F) ₂ : Eu or (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu is more preferable, and BaMgAl ₁₀ O ₁₇ : Eu, Sr ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : More preferably, Eu or Ba ₃ MgSi ₂ O ₈ : Eu is included. Of these, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu or (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu is particularly preferable for illumination and display applications.

  Any one of the blue phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

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

Such yellow phosphors include various oxides, nitrides, oxynitrides, sulfides,
Examples thereof include phosphors such as oxysulfides.
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} is garnet phosphor having a garnet structure represented by the representative) like a tetravalent metallic ^{_{element, AE 2 M d O 4:}} . Eu ( where, AE is, Ba, Sr, Ca, Mg , And at least one element selected from the group consisting of Zn, and M ^d represents Si and / or Ge)), etc., and constituent elements of the phosphors of these systems Oxynitride Phosphors in which a Part of Oxygen is Replaced with Nitrogen AEAlSiN _3: Ce (., Where, AE is, Ba, Sr, Ca, Mg and represents at least one element selected from the group consisting of Zn) of the nitride-based fluorescent material or the like having a CaAlSiN ₃ structure, such as Ce And the phosphor activated in step (b).

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, Cax (Si, Al) ₁₂ (O, N) ₁₆ : phosphor activated by Eu such as oxynitride phosphor having SiAlON structure such as Eu, (M _1-A-B Eu _A Mn _B ) ₂ (BO ₃ ) _1-P (PO ₄ ) _P X (where M represents one or more elements selected from the group consisting of Ca, Sr, and Ba, and X represents F, Cl, and Br) Represents one or more elements selected from the group consisting of: A, B, and P are 0.001 ≦ A ≦ 0.3, 0 ≦ B ≦ 0.3, and 0 ≦ P ≦ 0.2, respectively. It is also possible to use Eu-activated or Eu / Mn co-activated halogenated borate phosphors, etc. That.

  Examples of the yellow phosphor include fluorescent dyes such as brilliant sulfoflavine FF (Colour Index Number 56205), basic yellow HG (Colour Index Number 46040), eosine (Colour Index Number 45380), and rhodamine 6G (Colour Index Number 45160). Etc. can also be used.

  Any one of the yellow phosphors exemplified above may be used alone, or two or more thereof may be used in any combination and ratio.

<Green phosphor>
When a green phosphor is used as the second phosphor, any green phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the 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 542 nm or less, and further preferably 535 nm or less. If this emission peak wavelength is too short, it tends to be bluish, while if it is too long, it tends to be yellowish, and the characteristics as green light may deteriorate.

Specifically, the green phosphor is composed of, for example, fractured particles having a fractured surface, and emits a green region with (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : with europium represented by Eu. Examples include active 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

  In addition, as the green phosphor, it is also possible to use a pyridine-phthalimide condensed derivative, a benzoxazinone-based, a quinazolinone-based, a coumarin-based, a quinophthalone-based, a naltalimide-based fluorescent pigment, or an organic phosphor such as a terbium complex. is there.

  Any one of the green phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.

<Selection of second phosphor>
As said 2nd fluorescent substance, 1 type of fluorescent substance may be used independently, and 2 or more types of fluorescent substance may be used together by arbitrary combinations and a 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 the light emitting device of the present invention, the presence / absence and type of the second phosphor (yellow phosphor, blue phosphor, green phosphor, etc.) described above may be appropriately selected according to the use of the light emitting device. . For example, when the light emitting device of the present invention is configured as an orange or red light emitting device, only the first phosphor (orange or red phosphor) may be used, and the second phosphor is usually used. Is unnecessary.

  On the other hand, when the light-emitting device of the present invention is configured as a light-emitting device that emits white light, the first light-emitting body, the first phosphor (orange or red phosphor), and a desired white light are obtained. What is necessary is just to combine a 2nd fluorescent substance appropriately. Specifically, examples of preferable combinations of the first light emitter, the first phosphor, and the second phosphor in the case where the light emitting device of the present invention is configured as a white light emitting device include the following: (I) to (iii) are included.

(I) A blue phosphor (such as a blue LED) is used as the first phosphor, a red phosphor (such as the phosphor of the present invention) is used as the first phosphor, and green fluorescence is used as the second phosphor. Use the body.

(Ii) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a red phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second phosphor is used as the second phosphor. A blue phosphor and a green phosphor are used in combination.

(Iii) A blue phosphor (such as a blue LED) is used as the first phosphor, an orange phosphor (such as the phosphor of the present invention) is used as the first phosphor, and green fluorescence is used as the second phosphor. Use the body.

Specific examples of the above phosphor combinations are listed in the following Tables a) to h).
However, (Ca, Sr) AlSiNi ₃ : Eu exemplified as the deep red phosphor in the following Tables d), h) and Table 5) below refers to the amount of Ca relative to the total amount of Ca and Sr. It is a phosphor having an emission peak wavelength in the range of 40 mol% or more and a wavelength of 630 nm to 700 nm, and may be the phosphor of the present invention.

  Among these combinations, a light emitting device using a semiconductor light emitting element and a phosphor in combinations shown in the following Tables 1) to 7) is particularly preferable.

  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 by being dispersed in a liquid medium that is a sealing material.
Examples of the liquid medium include the same ones as described in the above-mentioned section [Phosphor-containing composition].

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

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

<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.

<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 representative example of a light-emitting device in a form called a surface-mount type, and 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.

<Applications 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.

[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.

[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 together 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.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded.
In each Example and each Comparative Example described later, various evaluations were performed by the following methods.

<Emission spectrum and luminance measurement method>
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 450 nm to 475 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. An emission spectrum was obtained through signal processing such as sensitivity correction. During the measurement, the slit width of the light receiving side spectroscope was set to 1 nm and the measurement was performed.
Moreover, the relative brightness | luminance which made the value of the stimulus value Y of the fluorescent substance in the reference example 1 mentioned later 100% from the stimulus value Y in the XYZ color system calculated based on JISZ8724 was calculated. The luminance was measured by cutting excitation blue light.

<Measuring method of chromaticity coordinates>
Chromaticity coordinates CIEx and CIEy in the XYZ color system defined by JIS Z8701 were calculated from data in the wavelength region of 480 nm to 800 nm (in the case of excitation wavelength of 455 nm) of the emission spectrum by a method according to JIS Z8724.

<Chemical composition>
The analysis was performed by ICP emission spectroscopy (Inductively Coupled Plasma-Atomic Emission Spectrometry; hereinafter sometimes referred to as “ICP method”) using an ICP chemical analyzer “JY 38S” manufactured by Jobibon.

<Powder X-ray diffraction measurement>
The details of the powder X-ray diffraction measurement conditions are as follows.
Measuring apparatus: PANALYTIC PW1700 type powder X-ray diffraction measurement conditions:
X-ray source: Cu—Kα ray (λ = 1.54184Å),
Output setting: 40 kV, 30 mA
Optical conditions during measurement: Divergent slit = 1 °
Scattering slit = 1 °
Receiving slit = 0.2mm
Diffraction peak position 2θ (Diffraction angle)
Measurement range: 2θ = 10 ° to 89.95 °
Scanning speed: 0.05 degree (2θ) / sec, continuous scanning Sample preparation: Sample molding jig (manufactured by Philips, formerly milled manually using an agate mortar)
PW1001 / 00 type).
Sample holder: PANALYTIC PW1781 / 00 type Sample part dimensions Outer diameter: 53mm
Inner diameter: 27mm
Depth: 2.6mm

<Temperature characteristics (maintenance rate of emission peak intensity)>
Measurement was performed using an MCPD7000 multi-channel spectrum measurement device manufactured by Otsuka Electronics as a light emission spectrum measurement device, a stage equipped with a cooling mechanism using a Peltier element and a heating mechanism using a heater, and a device equipped with a 150 W xenon lamp as a light source.
A cell containing a phosphor sample was placed on the stage, and the temperature was changed in the range of 20 ° C to 175 ° C. That is, after confirming that the surface temperature of the phosphor became constant at a measurement temperature in the range of 20 ° C. to 175 ° C., at each temperature, light with a peak wavelength of 455 nm extracted from the light source by a diffraction grating was used. An emission spectrum was measured by exciting the phosphor. The emission peak intensity was determined from the measured emission spectrum, and the peak intensity value at each temperature was calculated as a ratio when the peak intensity value at 25 ° C. was taken as 100.
In addition, the measured value of the surface temperature of the phosphor was a value corrected by using a temperature measured value by a radiation thermometer and a thermocouple.

<Luminance maintenance rate>
Measurement was performed using the above-mentioned apparatus to which a color luminance meter BM5A was added as a luminance measuring apparatus. Specifically, the relative value of the luminance value measured by the luminance measuring device to the luminance value at 25 ° C. was defined as the luminance maintenance rate.

<Excitation spectrum>
Using a fluorescence spectrophotometer F-4500 manufactured by Hitachi, Ltd., the orange emission peak intensity of each phosphor at 25 ° C. was monitored to obtain an excitation spectrum within a wavelength range of 300 nm to 530 nm. The peak wavelength to be monitored was the orange emission peak wavelength at the excitation wavelength of 465 nm of each phosphor.

  In the following, the simple metals used for the alloy raw materials are all high-purity products having an impurity concentration of 0.01 mol% or less. In addition, as for the shape of the raw metal, Sr is a lump and the others are granular.

Example 1
Each metal was weighed so that the metal element composition ratio was Al: Si = 1: 1 (molar ratio), and after melting the raw material metal using a high-frequency induction melting furnace in an argon atmosphere using a graphite crucible, the crucible Was poured into a mold and solidified to obtain an alloy (mother alloy) having a metal element composition ratio of Al: Si = 1: 1 (molar ratio).

The mother alloy and other raw metals were weighed so that the metal element composition ratio would be Eu: Sr: Ca: Al: Si = 0.008: 0.792: 0.2: 1: 1 (molar ratio). After evacuating the inside of the furnace to 5 × 10 ⁻² Pa, the evacuation was stopped, and the furnace was filled with argon to a predetermined pressure. In this furnace, melt the mother alloy in the calcia crucible, and then add Sr, Eu, Ca, and after confirming that the molten metal with all components melted is stirred by the induced current, the copper mold cooled with water from the crucible The molten metal was poured into a (plate shape with a thickness of 40 mm) and solidified.

The obtained plate-like alloy having a thickness of 40 mm and a weight of about 5 kg was subjected to composition analysis by the ICP method. About 10g was sampled from one point near the center of gravity of the plate and one point near the end face of the plate, and elemental analysis was performed by ICP method.
Central part of plate Eu: Sr: Ca: Al: Si = 0.000: 0.782: 0.212: 1: 0.986,
End face of the plate Eu: Sr: Ca: Al: Si = 0.000: 0.756: 0.21: 1: 0.962
The composition was substantially the same in the range of analysis accuracy. Therefore, it was considered that each element including Eu was distributed uniformly.

The obtained alloy showed a powder X-ray diffraction pattern similar to Sr (Si _0.5 Al _0.5 ) ₂ and was identified as an intermetallic compound called AlB ₂ type alkaline earth silicide.

5 g of alloy powder obtained by pulverizing this plate-like alloy lump in a nitrogen stream to a weight median diameter of 20.0 μm is filled in a boron nitride tray having an inner diameter of 55 mm, and a hot isostatic pressing device (HIP device). Set inside. The inside of the apparatus was evacuated to 5 × 10 ⁻¹ Pa, heated to 300 ° C., and evacuated at 300 ° C. for 1 hour. Thereafter, filling with 1 MPa of nitrogen, releasing the pressure to 0.1 MPa after cooling, and then filling with nitrogen again to 1 MPa were repeated twice. Before starting the heating, nitrogen was charged up to 50 MPa, the sample temperature was raised to 1900 ° C. at 600 ° C./hour, and at the same time the internal pressure was increased to 190 MPa at an average of 45 MPa / hour. Then, while maintaining the internal pressure of the apparatus at 190 MPa, it was heated to 1900 ° C., held at this temperature for 2 hours, and the target composite nitride phosphor having a charged composition of Sr _0.792 Ca _0.2 AlSiN ₃ : Eu _0.008 Got.

The powder X-ray diffraction pattern of the obtained phosphor is as shown in FIG. 4, and an orthorhombic crystal phase of the same type as CaAlSiN ₃ was generated. The peak position (2θ) was as shown in <Table C-3>, and the peak intensity ratio I of each region of this phosphor was as shown in <Table C-1>.
Moreover, about this fluorescent substance, the measurement result of the luminescent property was shown to <Table C-1>, and the ICP chemical analysis result was shown to <Table C-2>.
In <Table C-1>, the luminance is 100% of the luminance of the phosphor obtained in Reference Example 1 described later.

About the obtained fluorescent substance, the temperature characteristic (emission peak intensity maintenance factor) and the luminance maintenance factor were measured by the above-mentioned method. The results are shown in FIG. 5 for the temperature characteristics and in FIG. 6 for the luminance maintenance ratio. In the measurement of the temperature characteristics and the luminance maintenance rate, YAG: Ce yellow phosphor (P46-Y3 manufactured by Kasei Optonics) was simultaneously measured as a comparative sample.
Moreover, the excitation spectrum was measured by the above-mentioned method about the obtained fluorescent substance. The measured excitation spectrum is shown in FIG.

( Reference Example 2)
In the production of the phosphor raw material alloy in Example 1, each metal and the master alloy so that the metal element composition ratio is Eu: Sr: Al: Si = 0.008: 0.992: 1: 1 (molar ratio). A plate-like alloy was produced in the same manner as in Example 1 except that was weighed.
When the composition of the obtained alloy was analyzed by the ICP method, it matched within the range of the charged composition and the accuracy of the analysis. Therefore, it was considered that each element including Eu was distributed uniformly.

The obtained alloy main phase shows a powder X-ray diffraction pattern similar to that of _{Sr (Si 0.5 Al 0.5) 2} , it obtained alloy is a single phase was observed.
The obtained plate-like alloy was pulverized and fired under the same conditions as in Example 1. From the obtained composite nitride, a non-light emitting portion was removed, washed with water, and dried to obtain a phosphor having a charged composition of Sr _0.992 AlSiN ₃ : Eu _0.008 .

As a result of powder X-ray diffraction measurement of the obtained phosphor, an orthorhombic crystal phase of the same type as CaAlSiN ₃ was generated. The peak position (2θ) was as shown in <Table C-3>, and the peak intensity ratio I of each region of this phosphor was as shown in <Table C-1>.
Moreover, about this fluorescent substance, the measurement result of the light emission characteristic was shown in <Table C-1>, and the result of having analyzed the composition of the fluorescent substance by ICP method was shown in <Table C-2>.

Further, with respect to the obtained phosphor, the temperature characteristics and the luminance maintenance rate were measured by the same method as in Example 1. The results are shown in FIG. 5 for the temperature characteristics and in FIG. 6 for the luminance maintenance ratio.
Moreover, the excitation spectrum was measured by the above-mentioned method about the obtained fluorescent substance. The measured excitation spectrum is shown in FIG.

( Reference Example 3)
In Example 1, each metal and the master alloy are weighed so that the metal element composition ratio is Eu: Sr: Ca: Al: Si = 0.006: 0.494: 0.5: 1: 1 (molar ratio). A plate-like alloy having a weight of about 5 kg was produced under the same conditions as in Example 1 except that.
When the composition of the obtained alloy was analyzed by the ICP method, it matched within the range of the charged composition and the accuracy of the analysis. Therefore, it was considered that each element including Eu was distributed uniformly.

The obtained alloy showed a powder X-ray diffraction pattern whose main phase was similar to Sr (Si _0.5 Al _0.5 ) ₂ . Moreover, from the powder X-ray diffraction pattern, it was confirmed that the obtained alloy was a single phase.
This plate-like alloy was pulverized and fired under the same conditions as in Example 1 to obtain a phosphor having a charged composition of Sr _0.494 Ca _0.5 AlSiN ₃ : Eu _0.006 .

As a result of powder X-ray diffraction measurement of the obtained phosphor, an orthorhombic crystal phase of the same type as CaAlSiN ₃ was generated.
The peak position (2θ) was as shown in <Table C-3>, and the peak intensity ratio I of each region of this phosphor was as shown in <Table C-1>.

Moreover, the measurement result of the luminescent property about this fluorescent substance was shown in <Table C-1>.
Further, with respect to the obtained phosphor, the temperature characteristics and the luminance maintenance rate were measured by the same method as in Example 1. The results are shown in FIG. 5 for the temperature characteristics and in FIG. 6 for the luminance maintenance ratio.

( Reference Example 4)
EuN, Sr ₃ N ₂ , Ca ₂ N ₃ so that the metal element composition ratio is Eu: Sr: Ca: Al: Si = 0.008: 0.792: 0.2: 1: 1 (molar ratio). (CERAC 200 mesh pass), AlN (Tokuyama Grade F), Si ₃ N ₄ (Ube Industries SN-E10) were weighed in an argon atmosphere and mixed in a mortar. The obtained raw material mixture was nitrided under the same conditions as in Example 1 to obtain a phosphor having a charged composition of Sr _0.792 Ca _0.2 AlSiN ₃ : Eu _0.008 .
EuN and Sr ₃ N ₂ were obtained by nitriding raw materials (rear metallic and Aldrich, respectively) at 800 ° C. for 12 hours in a 4% hydrogen-containing nitrogen atmosphere.

As a result of powder X-ray diffraction measurement of the obtained phosphor, an orthorhombic crystal phase of the same type as CaAlSiN ₃ was generated. The peak position (2θ) was as shown in <Table C-3>, and the peak intensity ratio I of each region of this phosphor was as shown in <Table C-1>.
Moreover, the measurement result of the luminescent property about this fluorescent substance was shown in <Table C-1>.

(Comparative Example 1)
EuN, Sr ₃ N ₂ , Ca ₂ N ₃ so that the metal element composition ratio is Eu: Sr: Ca: Al: Si = 0.008: 0.792: 0.2: 1: 1 (molar ratio). (CERAC 200 mesh pass), AlN (Tokuyama Grade F), Si ₃ N ₄ (Ube Industries SN-E10) were weighed in an argon atmosphere and mixed in a mortar. The obtained raw material mixture was nitrided by heating at 1600 ° C. for 2 hours and then at 1800 ° C. for 2 hours under a 0.92 MPa pressure in a nitrogen atmosphere to obtain a composite nitride phosphor. EuN and Sr ₃ N ₂ are produced by nitriding raw metal (rear metallic and Aldrich, respectively) at 800 ° C. for 12 hours in a 4% hydrogen-containing nitrogen atmosphere.

The powder X-ray diffraction pattern of the obtained phosphor is shown in FIG. 8, the evaluation results and the measurement results of the emission characteristics are shown in <Table C-1>, and the results of analyzing the composition of the phosphor by the ICP method are shown in <Table C- 2>. From Table C-1, it can be seen that, in addition to the orthorhombic crystal phase of the same type as CaAlSiN ₃ , impurities appearing as peaks in the aforementioned regions 1 to 6 are generated.

(Comparative Example 2)
A composite nitride phosphor was obtained under the same conditions as in Example 1 except that nitriding was performed in an atmosphere heating furnace (1600 ° C., normal pressure).
The evaluation results of the powder X-ray diffraction and the measurement results of the light emission characteristics of the obtained phosphor are shown in <Table C-1>, and the results of analyzing the composition of the phosphor by the ICP method are shown in <Table C-2>. From Table C-1, it can be seen that, in addition to the orthorhombic crystal phase of the same type as CaAlSiN ₃ , impurities appearing as peaks in the aforementioned regions 1 to 6 are generated.

(Reference Example 1)
Ca ₃ N ₂ (200 mesh pass manufactured by CERAC), AlN (manufactured by Tokuyama Co., Ltd.) so that the metal element composition ratio is Eu: Ca: Al: Si = 0.008: 0.992: 1: 1 (molar ratio). Grade F), Si ₃ N ₄ (SN-E10 manufactured by Ube Industries), and Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd.) were weighed in an argon atmosphere and mixed using a mixer. The obtained raw material mixture was filled into a boron nitride crucible and set in an atmosphere heating furnace. After evacuating the inside of the apparatus to 1 × 10 ⁻² Pa, evacuation was stopped, and after filling the apparatus with nitrogen up to 0.1 MPa, the temperature was raised to 1600 ° C. and held at 1600 ° C. for 5 hours, A composite nitride phosphor was obtained. The emission peak wavelength of this phosphor at an excitation wavelength of 465 nm was 648 nm. Table C-3 shows the peak position (2θ) of the powder X-ray diffraction pattern of this phosphor.

1 Phosphor-containing part (second light emitter)
2 Excitation light source (first light emitter) (LD)
3 Substrate 4 Light-emitting device 5 Mount lead 6 Inner lead 7 Excitation light source (first light emitter)
8 Phosphor-containing resin part 9 Conductive wire 10 Mold member 11 Surface emitting illumination device 12 Holding case 13 Light emitting device 14 Diffusion plate

Claims (12)

In the powder X-ray diffraction pattern measured by using a CuKα ray (1.54184］), which is a phosphor represented by the following general formula [2]:
2θ has the strongest peak in the range of 34 ° to 36.36 °,
The impurity peaks appearing in addition to the crystal phase of the phosphor in the region 1 to region 6 shown in the following <Table A> are those in the region 1 (10 ° to 17 °) shown in the following <Table A>. A phosphor having a peak intensity ratio I of a peak existing in a range of less than 0.2%, and a peak intensity ratio I in regions 2 to 6 being 8% or less.
However, the peak intensity ratio I is the corresponding peak with respect to the height Imax of the strongest peak existing in the range of 2θ between 34 ° and 36.36 ° in the powder X-ray diffraction pattern where 2θ is in the range of 10 ° to 60 °. The ratio of the height Ip (Ip × 100) / Imax (%). Here, the peak intensity is a value obtained by performing background correction.
M ^{1 ′} _{a ′} Sr _{b ′} Ca _{c ′} M ^{2 ′} _{d ′} Al _{e ′} Sif _′ N _{g ′}
[2]
(However, a ′, b ′, c ′, d ′, e ′, f ′, g ′ are values in the following ranges, respectively.
0.00001 ≦ a ′ ≦ 0.15,
0.7 ≦ b ′ ≦ 0.99999,
0 ≦ c ′ <1,
0 ≦ d ′ <1,
a ′ + b ′ + c ′ + d ′ = 1,
0.5 ≦ e ′ ≦ 1.5,
0.5 ≦ f ′ ≦ 1.5,
2.5 ≦ g ′ ≦ 3.5
M ^{1 ′} represents Eu or an activation element composed of Eu and Ce, and M ^{2 ′} represents Mg and / or Ba. ) Emission peak wavelength 60 0 nm or more and equal to or less than 6 4 0 nm, the phosphor of claim 1.   The phosphor according to claim 1 or 2, wherein the oxygen content is 5% by weight or less. The crystal structure is orthorhombic and the lattice constant is 9.75Å ≦ a ≦ 9.93Å, 5.69Å ≦ b ≦.
The phosphor according to any one of claims 1 to 3, wherein 5.77 ?, 5.1 ?? c? 5.18 ?, 280? ³ ? V? 298? ³ .   The phosphor according to any one of claims 1 to 4, wherein the internal quantum efficiency is 0.6 or more.   A phosphor-containing composition comprising the phosphor according to any one of claims 1 to 5 and a liquid medium. A first light emitter, and a second light emitter that emits visible light by irradiation of light from the first light emitter,
6. A light emitting device, wherein the second light emitter contains at least one of the phosphors according to claim 1 as a first phosphor.   The light emitting device according to claim 7, wherein the second phosphor includes at least one phosphor having a light emission peak wavelength different from that of the first phosphor as the second phosphor. . The first light emitter has a light emission peak in a wavelength range of 420 nm to 500 nm;
The light emitting device according to claim 8, wherein the second light emitter contains, as the second phosphor, at least one kind of phosphor having a light emission peak in a wavelength range of 500 nm to 550 nm. . The first light emitter has a light emission peak in a wavelength range of 300 nm or more and 420 nm or less;
The second phosphor is, as the second phosphor, at least one phosphor having an emission peak in a wavelength range of 420 nm to 490 nm and at least one having an emission peak in a wavelength range of 500 nm to 550 nm. The light emitting device according to claim 8, further comprising a seed phosphor.   An image display device comprising the light-emitting device according to claim 7.   An illumination device comprising the light-emitting device according to claim 7.