JP2011256340A - Phosphor, phosphor-containing composition using the phosphor, light emitting device, image display device and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor excellent in color rendering performance, a phosphor-containing composition using the phosphor, a light emitting device, an image display device using the light emitting device, and a lighting device.SOLUTION: The phosphor has a composition expressed by the following formula [1]: M)A1SiON: M(wherein, Mis a divalent metal element selected from Sr, Ba, Ca, Mg and Zn; Mis an activating element selected from Cr, Mn, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb; 0≤x≤1; 0<y≤1; 0≤z≤13; and 3.6≤n≤4.4.).

Description

  The present invention relates to a phosphor, 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.

  The phosphor is used for a fluorescent display tube (VFD), a field emission display (FED), a plasma display panel (PDP), a cathode ray tube (CRT), a white light emitting diode (LED), 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, electron beams, blue light, etc. When excited by a high energy excitation source, it emits visible light.

In recent years, there has been a demand for further improvements in performance such as color rendering in light emitting devices, and the development of new phosphors is desired.
Further, instead of conventional phosphors such as silicate phosphors, phosphate phosphors, aluminate phosphors and sulfide phosphors, nitride phosphors and oxynitride phosphors are also being searched for.

In Non-Patent Document 1, as an oxynitride, (Sr _1-x Ca _x ) _{(11 + 16y−25z) / 2} (Si _1−y Al _y ) ₁₆ (N _1−z O _z ) ₂₅ (x = 0.24) , Y = 0.18, z = 0.19). _The examples were synthesized substance represented by _{Sr 3.44 Ca 1.07 Si 13.12 Al 2.88} N 20.14 O 4.87 is described.
Patent Document 1 and Non-Patent Document 2 disclose Sr ₃ Si ₁₃ Al ₃ O ₂ N ₂₁ : Eu and Sr ₂ Si ₇ Al ₃ ON ₁₃ : Eu, respectively.
Also, further, in Non-Patent Document _{3, Sr 5 Al 5 + x} Si 21-x N 35-x O z: Eu 2+ (x ≒ 0) is disclosed. _The examples were synthesized substance represented by _{Sr 5 Al 5 Si 21 N 35} O z is described.

International Publication No. 2007/105631

J. et al. A. Kechel et al. Eur. J. et al. Inorg. Chem. 2009 (2009) 3326-3332 Y. Fukuda et al, Appl. Phys. Express. 2 (2009) 012401 Oliver Oeckler et al, Chem. Eur. J. et al. 2009, 15, 5311-5319

However, the substance described in Non-Patent Document 1 does not contain an activating element, and there is no suggestion that it can be used as a phosphor instead of a phosphor.
Further, the phosphors described in Patent Document 1, Non-Patent Document 2, and Non-Patent Document 3 have narrow-band light emission, and further improvement is required in terms of color rendering properties.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a phosphor having a novel composition excellent in color rendering properties, a phosphor-containing composition and a light-emitting device using the phosphor, An object of the present invention is to provide an image display device and a lighting device using a light emitting device.

  In view of the above problems, the present inventors have searched for a new fluorescent substance, found that a phosphor having a composition represented by the following formula [1] emits light with good color rendering, and completed the present invention. . In addition, the present inventors have found that this phosphor can be suitably used for applications such as a light emitting device, and have completed the present invention.

  That is, the gist of the present invention is as follows.

(1) A phosphor having a composition represented by the following formula [1].
^{_{M 1 n (1-y)}} Al nx + z Si 16- (nx + z) O nx + z N 20 + n- (nx + z): M 2 y ··· [1]
(In the above formula [1], M ¹ represents at least one divalent metal element selected from the group consisting of Sr, Ba, Ca, Mg, and Zn, and M ² represents Cr, Mn, Ce, Pr, At least one type of activating element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb is shown.
Moreover, x, y, z, and n show the numerical value of the following ranges, respectively.
0 ≦ x ≦ 1
0 <y ≦ 1
0 ≦ z ≦ 13
3.6 ≦ n ≦ 4.4)

(2) The phosphor according to (1), which has a superstructure.

(3) The phosphor according to (1) or (2), which comprises a crystal phase A defined below.

In an X-ray diffractometer using a CuKα X-ray source, a crystal phase in which a diffraction peak is observed in a diffraction angle (2θ) range of 27 ° to 29 ° (R0), which is based on the diffraction peak (P0) As diffraction peaks, the five diffraction peaks derived from the black angle (θ0) of P0 are designated as P1, P2, P3, P4, and P5 in order from the low angle, and the diffraction angle ranges of these diffraction peaks are defined as R1, R2, R1, R2, R3, R4 and R5 are R3, R4 and R5, respectively.
R1 = R1s-R1e
R2 = R2s-R2e
R3 = R3s-R3e
R4 = R4s-R4e
R5 = R5s-R5e
An angle range of at least one diffraction peak in all ranges of R1, R2, R3, R4, and R5,
In addition, among P1, P2, P3, P4, and P5, the intensity of P0 has a diffraction peak height ratio of 20% or more with respect to the height of the diffraction peak having the highest diffraction peak height. Yes,
Among P1, P2, P3, P4, and P5, the peak intensity of at least one of P1, P2, P3, P4, and P5 other than P1, P2, P3, P4, and P5 with respect to the height of the diffraction peak having the highest diffraction peak height Has a diffraction peak height ratio of 5% or more.

Here, when there are two or more diffraction peaks in each angular range of the angular ranges R0, R1, R2, R3, R4, and R5, the peak having the highest peak intensity among these is P0, P1, Let P2, P3, P4 and P5.
R1s, R2s, R3s, R4s, and R5s indicate start angles of R1, R2, R3, R4, and R5, respectively. R1e, R2e, R3e, R4e, and R5e are R1, R2, R3, and R5e, respectively. The end angles of R4 and R5 are shown, and specifically the following angles are shown.
R1s: 2 × arcsin {sin (θ0) / (0.943 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (0.943 × 0.985)}
R2s: 2 × arcsin {sin (θ0) / (0.912 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (0.912 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (0.869 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (0.869 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.834 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.834 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.731 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.731 × 0.985)}

(4) A phosphor-containing composition comprising the phosphor according to any one of (1) to (3) and a liquid medium.

(5) 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 (3). A light-emitting device comprising one or more of the phosphors according to any one of the above as the first phosphor.

(6) An image display device comprising the light-emitting device according to (5) as a light source.

(7) An illumination device comprising the light-emitting device according to (5) as a light source.

ADVANTAGE OF THE INVENTION According to this invention, the fluorescent substance of the novel composition which light-emits blue thru | or green thru | or red can be provided. The phosphor of the present invention exhibits broadband emission with a broad emission peak and is excellent in color rendering.
In addition, by using the phosphor of the present invention, a high-performance light-emitting device, image display device, and lighting device can be provided.

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. 2 is a chart showing a powder X-ray diffraction pattern of the phosphor obtained in Example 1. FIG. 2 is a chart showing an emission spectrum of the phosphor obtained in Example 1. FIG. 6 is a chart showing a powder X-ray diffraction pattern of the phosphor obtained in Comparative Example 1. 6 is a chart showing an emission spectrum of the phosphor obtained in Comparative Example 1. 6 is a chart showing a powder X-ray diffraction pattern of the phosphor obtained in Example 2. FIG. 6 is a chart showing an emission spectrum of the phosphor obtained in Example 2. 6 is a chart showing an excitation spectrum of the phosphor obtained in Example 2. 6 is a chart showing powder X-ray diffraction patterns of the phosphors obtained in Examples 3, 6, 10, and 15. It is a chart which shows the emission spectrum of the fluorescent substance obtained in Example 3, 6, 10, 15. It is a chart which shows the powder X-ray-diffraction pattern of the fluorescent substance obtained in Examples 16-21. It is a chart which shows the emission spectrum of the fluorescent substance obtained in Examples 16-21. It is a chart which shows the powder X-ray-diffraction pattern of the fluorescent substance obtained in Examples 22-25. It is a chart which shows the emission spectrum of the fluorescent substance obtained in Examples 22-25.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following descriptions, 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.
Further, the relationship between the color name and the chromaticity coordinates in this specification is all based on the JIS standard (JIS Z8110).

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

[1. Phosphor]
[1-1. composition]
The phosphor of the present invention has a composition represented by the following formula [1].
^{_{M 1 n (1-y)}} Al nx + z Si 16- (nx + z) O nx + z N 20 + n- (nx + z): M 2 y ··· [1]
(In the above formula [1], M ¹ represents at least one divalent metal element selected from the group consisting of Sr, Ba, Ca, Mg, and Zn, and M ² represents Cr, Mn, Ce, Pr, At least one type of activating element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb is shown.
Moreover, x, y, z, and n show the numerical value of the following ranges, respectively.
0 ≦ x ≦ 1
0 <y ≦ 1
0 ≦ z ≦ 13
3.6 ≦ n ≦ 4.4)

Here, in the formula [1], M ¹ is at least one divalent metal element selected from the group consisting of Sr, Ba, Ca, Mg, and Zn. M ¹ may contain any one of these elements alone, or may contain two or more kinds in any combination and ratio. M ¹ is preferably at least one selected from the group consisting of Sr, Ba, and Ca. At this time, the ratio of Sr, Ba, or Ca to the entire M ¹ is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more.

Incidentally, it is possible to adjust, as will be described later, Sr contained as M ^1, Ba, the light emission color of the phosphor by changing the proportion of each element of Ca.

In the formula [1], M ² is an activator element. Specifically, Cr, Mn, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb At least one transition metal element or rare earth element selected from the group consisting of As M ² , any one of these elements may be contained alone, or two or more may be contained in any combination and ratio.

Among them, M ² is preferably at least one element selected from the group consisting of rare earth elements Eu, Ce, Pr, Sm, Tb, and Yb, and at least Eu and / or Ce in terms of emission quantum efficiency. It is more preferable to contain Eu, and it is further preferable to make Eu essential in terms of the emission peak wavelength. The proportion of Eu in the entire M ² is preferably 50 mol% or more, more preferably 70 mol% or more, further preferably 90 mol% or more, and M ² is particularly preferably composed of Eu.

The M ² is considered to replace the site of the M ¹ element, and is present as a divalent cation and / or a trivalent cation in the phosphor of the present invention. In this case, the activation element M ² is towards the abundance ratio of the divalent cation is preferably higher. When M ² is Eu, specifically, the ratio of Eu ^{2+ to} the total amount of Eu is usually 20 mol% or more, preferably 50 mol% or more, more preferably 80 mol% or more, and particularly preferably 90 mol%. % Or more.

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

  In the formula [1], x is a variable related to N and O. The larger the value of x, the greater the O (oxygen) content. The range of x is usually 0 or more, preferably 0.5 or more, more preferably 0.75 or more, more preferably 0.9 or more, and the closer to 1, the better.

In the formula [1], y refers to the concentration of the activation element ^{M 2.} The range of y is usually larger than 0, preferably 0.005 or more, more preferably 0.02 or more, and usually 1 or less, preferably 0.5 or less, more preferably 0.3 or less. . If the value of y is too large, concentration quenching may occur, and if it is too small, the concentration of the luminescent center may be too low.

  In the formula [1], z means a ratio of replacing the Si—N group with the Al—O group in the phosphor crystal structure, and the larger the value of z, the more Al—O groups. means. For example, z = 13 when all Si—N groups contained in the phosphor of the present invention are replaced with Al—O groups. The range of z is usually 0 or more and usually less than 13, preferably 5 or less, more preferably 3 or less.

In the formula [1], n denotes the percentage that contains ^M 1 (O, N) in the composition of the phosphor. The range of n is usually 3.6 or more, preferably 3.8 or more, more preferably 3.9 or more, and usually 4.4 or less, preferably 4.2 or less, more preferably 4.1. It is as follows. If the value of n is too large or too small, an impurity phase may be easily generated.

The composition of the phosphor of the present invention is the sum of the composition ratio of Al and the composition ratio of Si with respect to the composition ratio of the M ¹ element (ie, {(nx + z) + 16- (nx + z)} / {n− (1 -Y)} = 16 / {n- (1-y)}) is usually 3.6 or more, preferably 3.9 or more, and usually 4.4 or less, preferably 4.1 or less. It is preferable. By having such a composition, a phosphor with high crystallinity is easily obtained.

In addition to the composition represented by the formula [1], the phosphor of the present invention may contain impurities, additive elements, and the like within a range that does not affect the properties of the phosphor. Examples of such elements include halogen elements such as F and Cl, transition metals such as Fe and Co, B (boron), and C (carbon). Further, in the phosphor of the present invention, together with the oxygen element or a nitrogen element, and that the M ¹ element is missing, it may M ¹ element enters extra into gaps of the crystal lattice. In some cases, part of the nitrogen element is present at the oxygen element site or part of the oxygen element is present at the nitrogen element site.

Specific examples of preferred compositions of the phosphor of the present invention are listed below, but the composition of the phosphor of the present invention is not limited to the following examples.
Preferable specific examples of the phosphor of the present invention include (Ca, Sr, Ba) Si ₄ N ₆ : (Eu, Ce, Mn), ((Ca, Sr, Ba) ₄ ON ₃ ) (AlSi ₁₅ N ₂₀ ). : (Eu, Ce, Mn), ((Ca, Sr, Ba) ₄ O ₂ N ₂ ) (Al ₂ Si ₁₄ N ₂₀ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) ₄ O _{3 N) (Al 3 Si 13} N 20) :( Eu, Ce, Mn), ((Ca, Sr, Ba) O) 4 (Al 4 Si 12 N 20) :( Eu, Ce, Mn), (( Ca, Sr, Ba) O) ₄ (Al ₅ Si ₁₁ ON ₁₉ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₆ Si ₁₀ O ₂ N ₁₈ ): (Eu , Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₇ Si ₉ O ₃ N ₁₇ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₈ Si ₈ O ₄ N ₁₆ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₉ Si ₇ O ₅ N ₁₅ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₀ Si ₆ O ₆ N ₁₄ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₁ Si ₅ O ₇ N ₁₃ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₂ Si ₄ O ₈ N ₁₂ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₃ Si ₃ O ₉ N ₁₁ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₄ Si ₂ O ₁₀ N ₁₀ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₅ Si ₉ O ₁₁ N ₉ ): (Eu, Ce, Mn), ((Ca, Sr, Ba) O) ₄ (Al ₁₆ O ₁₂ N ₈ ): (Eu, Ce, Mn).

[1-2. Characteristics of phosphor
<Weight median diameter>
The phosphor of the present invention preferably has a weight median diameter of usually 10 μm or more, more preferably 15 μm or more, and usually 30 μm or less, especially 20 μm or less. If the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate, which is not preferable. On the other hand, when the weight median diameter is too large, there is a tendency that uneven coating or blockage of a dispenser or the like occurs, which is not preferable. The weight median diameter of the phosphor of the present invention can be measured using a device such as a laser diffraction / scattering particle size distribution measuring device.

<Quantum efficiency and absorption efficiency>
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.

  The phosphor of the present invention is more preferable as its external 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 external quantum efficiency is low, the light emission efficiency tends to decrease, which is not preferable.

[1-3. Superstructure]
The phosphor of the present invention preferably has a superstructure. In particular, the phosphor of the present invention preferably includes a crystal phase A described later, and the crystal phase A preferably has a superstructure.
Hereinafter, the superstructure will be described.

When a streak or the like is observed in addition to a diffraction spot of the basic structure of the sample in X-ray diffraction or electron beam diffraction of the sample, it is said to have “superstructure”.
Superstructures include superlattice structures where streaks are observed at integer multiples of the basic structure and modulated structures where streaks are observed at non-integer multiples of the basic structure. The superstructure of the phosphor of the present invention is preferably a modulation structure.

For example, when the phosphor of the present invention having Sr as M ¹ has a crystal phase A described later, in the crystal structure, a block composed of Sr (O, N) and Si ₃ N ₄ -Al ₂ O ₃ The blocks formed of are stacked alternately, and this stacking tends to cause deviation (modulation). This shift (modulation) affects the surrounding environment of the partner element (for example, Sr) to which the luminescent center element (activator element) is replaced, and various different luminescent sites are formed. Light emission with a wide value range can be obtained.

  In general, there is one Sr site in the crystal in the average crystal structure obtained by the X-ray diffraction method, and an activating element such as Eu tends to be replaced by a solid solution at the Sr site. When the number of sites is one, observation of an emission peak with a narrow half-value width can be expected. However, when there is a stacking irregularity due to defect generation in the SrO layer as in the crystal phase A, when attention is paid to each Sr element, it is expected that Sr elements having various coordination environments exist in the crystal. Is done. Therefore, since the phosphor of the present invention has various light emitting sites formed by such a characteristic crystal structure, the light emission of an activating element such as Eu activated at the Sr site is broad with a large half width. Observed as emission peak.

[1-4. Crystal Phase A]
The phosphor of the present invention preferably contains a crystal phase A defined below.

In an X-ray diffractometer using a CuKα X-ray source, a crystal phase in which a diffraction peak is observed in a diffraction angle (2θ) range of 27 ° to 29 ° (R0), which is based on the diffraction peak (P0) As diffraction peaks, the five diffraction peaks derived from the black angle (θ0) of P0 are designated as P1, P2, P3, P4, and P5 in order from the low angle, and the diffraction angle ranges of these diffraction peaks are defined as R1, R2, R1, R2, R3, R4 and R5 are R3, R4 and R5, respectively.
R1 = R1s-R1e
R2 = R2s-R2e
R3 = R3s-R3e
R4 = R4s-R4e
R5 = R5s-R5e
At least one diffraction peak in all ranges of R1, R2, R3, R4, and R5, and among P1, P2, P3, P4, and P5, a diffraction peak The intensity of P0 is usually 20% or more, preferably 30% or more, more preferably 40% or more, particularly preferably 50% or more in terms of diffraction peak height ratio with respect to the height of the highest diffraction peak. Among the P1, P2, P3, P4, and P5, the diffraction peak height is the highest among the P1, P2, P3, P4, and P5. A crystal phase having a diffraction peak height ratio of at least 1 or more, usually 5% or more, preferably 10% or more, more preferably 15% or more, and particularly preferably 20% or more.

Here, when there are two or more diffraction peaks in each angular range of the angular ranges R0, R1, R2, R3, R4, and R5, the peak having the highest peak intensity among these is P0, P1, Let P2, P3, P4 and P5.
R1s, R2s, R3s, R4s, and R5s indicate start angles of R1, R2, R3, R4, and R5, respectively. R1e, R2e, R3e, R4e, and R5e are R1, R2, R3, and R5e, respectively. The end angles of R4 and R5 are shown, and specifically the following angles are shown.
R1s: 2 × arcsin {sin (θ0) / (0.943 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (0.943 × 0.985)}
R2s: 2 × arcsin {sin (θ0) / (0.912 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (0.912 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (0.869 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (0.869 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.834 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.834 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.731 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.731 × 0.985)}

Hereinafter, the crystal phase A will be described.
The crystal phase A has an orthorhombic unit cell. The lattice constant varies depending on the type of elements constituting the crystal, but the lattice constant a is usually 4.0 angstroms or more, preferably 4.5 angstroms or more, more preferably 5.0 angstroms or more, In general, it is 7.5 angstroms or less, preferably 7.0 angstroms or less, and more preferably 6.5 angstroms or less. The lattice constant b is usually 35 angstroms or more, preferably 36 angstroms or more, more preferably 37 angstroms or more, and usually 41 angstroms or less, preferably 40 angstroms or less, more preferably 39 angstroms or less. The lattice constant c is usually 8.0 angstroms or more, preferably 8.5 angstroms or more, more preferably 9.0 angstroms or more, and usually 11.5 angstroms or less, preferably 11.0 angstroms or less. Preferably it is 10.5 angstroms or less.

  The lattice constant can be obtained by an X-ray diffraction and neutron diffraction analysis method using a Rietveld method, and the space group is uniquely obtained by electron diffraction or convergent electron diffraction. Can do. The Rietveld analysis may be carried out using the analysis program Rietan 2000 with reference to Izumi Nakai and Fujio Izumi, “Practice of Powder X-ray Analysis—Introduction to the Rietveld Method” published by Asakura Shoten (2002). .

  Furthermore, the space group of the crystal phase A preferably belongs to No. 43 (Fdd2) based on “International Tables for Crystallography (Third, Revised Edition), Volume A Space-Group Symmetry”.

  The identification of the crystal phase can also be performed using the crystal system or the space group described above. However, the crystal phase of the phosphor of the present invention causes distortion or subtle structural change in the crystal structure due to the change in composition, thereby changing the crystal system and / or space group. There are aspects that make phase identification difficult. Therefore, in the following, the phosphor of the present invention is defined by the X-ray diffraction pattern necessary for identifying the crystal phase contributing to light emission.

  Usually, in order to specify (identify) that the crystal structures of two compounds are the same based on the X-ray diffraction pattern, the angle (2θ) of diffraction peaks indicated by these compounds should match. However, when the constituent element ratios are different as in the phosphor of the present invention, the angle of the diffraction peak moves even if the crystal structure is the same, so the angle of the diffraction peak cannot be defined in detail as a numerical value. Accordingly, the present inventors have focused on the diffraction peak plane distance calculated using the Bragg equation and specified the angle range of the diffraction peak by the following display method.

Bragg's formula:
d = λ / {2 × sin (θ)} (Formula 1)
θ = arcsin {λ / (2 × d)} (Formula 2)
Here, Expression 2 is a modification of Expression 1.
In Formula 1 and Formula 2, d, θ, and λ represent the following, respectively.
d: Surface spacing (Å)
θ: Bragg angle (°)
λ: CuKα X-ray wavelength = 1.54184 mm

Here, if the interplanar spacing range of the reference diffraction peak (P0) is defined as 3.3 to 3.1, the range of the diffraction angle (2θ) is 27 ° to 29 ° from Equation 2. Further, from the angle (θ 0) of the observed reference diffraction peak (P 0), the plane spacing (d 0) of the reference diffraction peak is expressed by the following expression 3 from expression 1.
d0 = λ / {2 × sin (θ0)} (Formula 3)

Five diffraction peaks other than the reference diffraction peak (P0) are designated as P1, P2, P3, P4, and P5 from the low angle side, and the angle ranges in which each peak appears are R1, R2, R3, R4, and R5 in order. Then, the angle range R1 in which P1 appears is determined as follows. That is, when the diffraction plane has a plane spacing of 0.943 times the plane spacing (d0) derived from the reference diffraction peak, and the deviation of the plane spacing due to the structural distortion is 1.5%, the starting angle of the angle range R1 ( R1s) and end angle (R1e) are derived from Equation 2 as follows.
R1s: 2 × arcsin {λ / (2 × d0 × 0.943 × 1.015)}
R1e: 2 × arcsin {λ / (2 × d0 × 0.943 × 0.985)}
Substituting Equation 3 for each,
R1s: 2 × arcsin {sin (θ0) / (0.943 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (0.943 × 0.985)}
It becomes.

Similarly, the angle range in which P2, P3, P4, and P5 appear is defined as 0.912 times, 0.869 times, 0.834 times, and 0.731 times with respect to the plane distance derived from the reference diffraction peak, Assuming that the deviation of the interplanar spacing due to the strain of the structure is uniformly 1.5%, each angle range is as follows.
R2s: 2 × arcsin {sin (θ0) / (0.912 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (0.912 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (0.869 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (0.869 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.834 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.834 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.731 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.731 × 0.985)}

  By confirming that each peak from the reference peaks P0 to P5 appears in the above-mentioned angle range in the obtained X-ray diffraction measurement result, the specific crystal structure (crystal phase A) in the present invention may exist. I can confirm.

The phosphor of the present invention contains cristobalite, which is a single crystal form of silicon dioxide identified by X-ray diffraction measurement using a CuKα X-ray source, or an impurity phase such as α-silicon nitride or β-silicon nitride. May be. The content of these impurity phases can be known by X-ray diffraction measurement, and the strongest diffraction peak intensity of the contained impurity phase is compared with the strongest peak intensity among the above-mentioned P0, P1, P2, P3, P4 and P5. In general, it is 40% or less, preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less. In particular, the crystalline phase A exists as a single phase without the peak of the impurity phase being observed. It is preferable. Thereby, the light emission intensity can be increased.
The X-ray diffraction measurement as described above can be performed by the method described in the examples.

[1-5. When Sr is required as M ¹ ]
The phosphor of the present invention preferably contains Sr as M ¹ from the viewpoint of the stability of the crystal structure. Hereinafter, the case where the phosphor of the present invention requires Sr as M ^{1 in the} formula [1] will be described.

<Composition>
In case of a mandatory Sr as M ^1, when the coexistence of Ba as ^{M 1,} the ratio of Sr to the total of ^{M 1} and ^{M 2} is greater than the normal 50 mol%, preferably 70 mol% or more, further Preferably it is 90 mol% or more, and it is especially preferable that it is 95 mol% or more. This is because a phosphor having a desired composition is easily obtained. The ratio of Ba to the total of ^{M 1} and ^{M 2} is preferably at most 25 mol%.
In case of a mandatory Sr as M ^1, when the coexistence of Ca as ^{M 1,} the ratio of Sr to the total of ^{M 1} and ^{M 2} are larger than the normal 85 mole%, preferably it is 90 mol% or more , 95 mol% or more is particularly preferable. This is because a phosphor having a desired composition is easily obtained.

The other condition in the formula [1] (element or included as M ^2, x, y, z, and n value range, etc.) can incorporate the foregoing description.

Further, the composition of the phosphor that requires Sr as M ¹ and contains the above-described crystal phase A can also be expressed using the following formula [2].
_{^{M 1 4 (1-a)}} Al 4b Si 4c O 4d N 4e: M 2 a ... [2]
(In the above formula [2], M ¹ represents at least one divalent metal element selected from the group consisting of Sr, Ba, Ca, Mg and Zn, and M ² represents Cr, Mn, Ce, Pr, At least one type of activating element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb is shown.
Moreover, a, b, c, d, and e show the numerical values of the following ranges, respectively.
0 <a ≦ 1
0 ≦ b ≦ 4.4
0 ≦ c ≦ 4.4
0 ≦ d ≦ 6.4
0 ≦ e ≦ 6.4)

In the formula [2], description of ^{M 1,} and ^{M 2} may hence the description relating to the formula [1].
In the formula [2], the range of a is usually larger than 0, preferably 0.005 or more, more preferably 0.02 or more, and usually 1 or less, preferably 0.5 or less, more preferably. Is 0.3 or less. If the value of a is too large, concentration quenching may occur, and if it is too small, the concentration of the luminescent center may be too low.
In the formula [2], the range of b is usually 0 or more, preferably 0.5 or more, and usually 4.4 or less, preferably 4 or less.
In the formula [2], the range of c is usually 0 or more, preferably 2 or more, and is usually 4.4 or less, preferably 3 or less.
In the formula [2], the range of d is usually 0 or more, preferably 2 or more, and is usually 6.4 or less, preferably 6 or less.
In the formula [2], the range of e is usually 0 or more, preferably 3 or more, and usually 6.4 or less, preferably 5 or less.

<Characteristics of phosphor>
The phosphor of the present invention in the case where Sr is essential in the composition range as described above emits blue or green light. More specifically, the emission peak wavelength is usually in the range of 460 nm or more and 530 nm or less.
When a blue-green phosphor is desired, the emission peak wavelength is preferably 460 nm or more and 510 nm or less, and when a green phosphor is desired, the emission peak wavelength is preferably 510 nm or more and 530 nm or less.

  Further, the full width at half maximum of the emission peak of the phosphor of the present invention when Sr is essential is usually 80 nm or more, preferably 90 nm or more, and usually 110 nm or less, preferably 100 nm or less. It is. If this half width is too narrow, the emission intensity tends to decrease, and if it is too wide, the color purity tends to decrease.

  The excitation wavelength of the phosphor of the present invention when Sr is essential is usually 200 nm or more, and is usually 460 nm or less, preferably 420 nm or less. Therefore, it can be applied to other uses such as fluorescent lamps in addition to LED uses.

<Crystal structure of phosphor>
A typical composition of the phosphor of the present invention when Sr is essential is obtained by activating Sr ₄ Al ₅ Si ₁₁ O ₅ N ₁₉ with Eu. As shown in the examples described later, this composition was confirmed to have the above-described crystal phase A as a new crystal structure by an X-ray diffraction method.
The phosphor of the present invention in which Sr is essential as M ¹ is preferably a complex oxynitride phosphor having a composition represented by the formula [1] and containing a crystal phase A.

  When a part of the Sr ion site is substituted with Ba, a new crystal structure (hereinafter sometimes referred to as “crystal phase B”) is obtained when the substitution amount exceeds a certain value. In addition, even when the Sr ion site is substituted with Ca, another crystal structure (hereinafter sometimes referred to as “crystal phase C”) is obtained when the substitution amount exceeds a certain value.

[1-6. When Ba is required as M ¹ ]
The phosphor of the present invention preferably contains Ba as M ¹ from the viewpoint of moving the emission peak to the orange to red region and further widening the half width. Hereinafter, a case where Ba is essential as M ¹ of the formula [1] will be described.

<Composition>
In case of a mandatory Ba as M ^1, when the coexistence of Sr as ^{M 1,} the ratio of Ba to the total of ^{M 1} and ^{M 2} is greater than the normal 50 mol%, preferably 70% or more, more preferably Is at least 90 mol%, particularly preferably at least 95 mol%. This is because the new phosphor crystal phase is the main phase.

The other condition in the formula [1] (element or included as M ^2, x, y, z, and n value range, etc.) can incorporate the foregoing description.

<Characteristics of phosphor>
The phosphor of the present invention in which Ba is essential in the composition range as described above, emits red light. More specifically, the emission peak wavelength is usually in the range of 590 nm or more, preferably 630 nm or more, and usually 700 nm or less, preferably 680 nm or less.

  Further, the full width at half maximum of the emission peak of the phosphor of the present invention when Ba is essential is usually 80 nm or more, preferably 90 nm or more, and usually 200 nm or less, preferably 150 nm or less. It is. If this half width is too narrow, the emission intensity tends to decrease, and if it is too wide, the color purity tends to decrease.

  The excitation wavelength of the phosphor of the present invention when Ba is essential is usually 180 nm or more, preferably 200 nm or more, and usually 500 nm or less, preferably 460 nm or less. Therefore, it can be applied to fluorescent lamps and the like in addition to LED applications.

[1-7. When Ca is required as M ¹ ]
The phosphor of the present invention preferably contains Ca as M ¹ from the viewpoint of moving the emission peak to the green region and further widening the half width. Hereinafter, a case where Ca is essential as M ¹ of the formula [1] will be described.

<Composition>
In case of a mandatory Ca as M ^1, when the coexistence of Sr as ^{M 1,} the ratio of Ca to the sum of ^{M 1} and ^{M 2} is usually 10 mol% or more, preferably 15 mol% or more, more preferably Is 20 mol% or more, and is usually 50 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less. This is because when the content of Ca is too large, an impurity phase tends to be generated.

The other condition in the formula [1] (element or included as M ^2, x, y, z, and n value range, etc.) can incorporate the foregoing description.

<Characteristics of phosphor>
The phosphor of the present invention in the case where Ca is essential as M ^{1 in the} composition range as described above emits green light. More specifically, the emission peak wavelength is usually in the range of 480 nm or more, preferably 500 nm or more, and usually 550 nm or less, preferably 540 nm or less.

The full width at half maximum of the emission peak of the phosphor of the present invention when Ca is essential as M ¹ is usually 80 nm or more, preferably 90 nm or more, and usually 200 nm or less, preferably Is 150 nm or less. If this half width is too narrow, the emission intensity tends to decrease, and if it is too wide, the color purity tends to decrease.

In addition, the excitation wavelength of the phosphor of the present invention when Ca is essential as M ¹ is usually 180 nm or more, preferably 200 nm or more, and usually 500 nm or less, preferably 460 nm or less. Therefore, it can be applied to fluorescent lamps and the like in addition to LED applications.

[2. Method for producing phosphor]
The method for producing the phosphor of the present invention is not particularly limited. For example, in the above-described formula [1], the raw material of the metal element M ¹ (hereinafter referred to as “M ¹ source” as appropriate), the Si raw material (hereinafter referred to as appropriate) (Referred to as “Si source”), a raw material of Al (hereinafter referred to as “Al source” as appropriate), and a raw material of the activation element M ² (hereinafter referred to as “M ² source” as appropriate) (mixing step). ) And firing the obtained mixture (firing step).

<Raw material>
Examples of the M ¹ source, Si source, Al source and M ² source used in the production of the phosphor of the present invention include oxides, hydroxides and carbonates of each of the elements M ¹ , Si, Al and M ^2. , Nitrates, sulfates, oxalates, carboxylates, halides and the like. From these compounds, the reactivity to the composite oxide, the low generation amount of NO _x , SO _{x and the} like during firing may be selected as appropriate.

Specific examples of the M ¹ source are listed as follows for each type of M ¹ element.
Of the M ¹ sources, SrO, SrCO ₃ , Sr ₂ N, Sr (NH), Sr (NH ₂ ) ₂ , Sr (OH) _{2 and the} like are preferable as specific examples of the Sr source.
Of the M ¹ sources, specific examples of the Ba source include BaCO ₃ , Ba ₂ N, Ba (NH), Ba (NH ₂ ) ₂ , Ba (OH) _{2, and the} like.
Of the M ¹ sources, specific examples of the Ca source include CaCO ₃ , Ca ₃ N ₂ , Ca (NH), Ca (NH ₂ ) ₂ , and Ca (OH) ₂ .
Among the M ¹ sources, specific examples of the Mg source are preferably MgCO ₃ , Mg ₃ N ₂ , Mg (NH), Mg (NH ₂ ) ₂ , Mg (OH) _{2, and the} like.
Of the M ¹ sources, specific examples of the Zn source include ZnCO ₃ , Zn ₃ N ₂ , Zn (NH), Zn (NH ₂ ) ₂ , Zn (OH) _{2, and the} like.

Specific examples of the Si source include Si ₃ N ₄ and SiO ₂ .

Specific examples of the Al source include AlN, Al ₂ O ₃ , Al (OH) ₃ , AlOOH, Al (NO ₃ ) _{3 and the} like.

Specific examples of M ² source, when listed separately for each type of M ² element is as follows.
Among the M ² sources, examples of Eu sources include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (OCO) ₆ , EuCl ₂ , EuCl ₃ , Eu (NO ₃ ) ₃ · 6H ₂ O Etc. Of these, Eu ₂ O ₃ , EuCl _{2 and the} like are preferable.

  Further, specific examples of the Ce source, Sm source, Tm source, Yb source, etc. include compounds in which Eu is replaced by Ce, Sm, Tm, Yb, etc. in the respective compounds listed as specific examples of the Eu source. .

Any of M ¹ source, Si source, Al source and M ² source may be used alone, or two or more may be mixed and used in an arbitrary combination and ratio.

Here, for _{example, Sr 3.96 Al 5 Si 11 O} 5 N 19: the charge composition in the case of producing a _{Eu 0.04,} the following equation [3].
3.96 · SrCO ₃ + 5 · AlN + 3.5 · Si ₃ N ₄ + 0.5 · SiO ₂ + 0.02 · Eu ₂ O ₃ ... [3]
However, when SrO is used instead of SrCO ₃ , it is considered that a phosphor according to the charged composition can be obtained within the accuracy of analysis.

<Mixing process>
The method for mixing the M ¹ source, the Si source, the Al source, and the M ² source is not particularly limited, but examples include the following methods (A) and (B).

(A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., or pulverization using mortar and pestle, etc. and mixer such as ribbon blender, V-type blender, Henschel mixer, or mortar and pestle A dry mixing method in which mixing is performed, and raw materials such as an M ¹ source, an Si source, an Al source, and an M ² source are pulverized and mixed.

(B) Add a solvent or dispersion medium such as water to raw materials such as M ¹ source, Si source, Al source, and M ² source, and mix using a pulverizer, mortar and pestle, or evaporating dish and stir bar. , Wet mixing method in which the solution or slurry is dried and then dried by spray drying, heat drying, or natural drying

<Baking process>
(Baking conditions)
In the firing step, a mixture of raw materials such as an M ¹ source, an Si source, an Al source, and an M ² source obtained by the above-described mixing step is usually used as a heat-resistant material such as a crucible or a tray made of a material having low reactivity with each raw material. It is carried out by placing in a container and heating.

  The temperature during firing is usually 1200 ° C. or higher, preferably 1500 ° C. or higher, and usually 2200 ° C. or lower, preferably 2000 ° C. or lower. If the firing temperature is too low, the crystals do not grow sufficiently and the particle size may be reduced. On the other hand, if the firing temperature is too high, the crystals may grow too much and the particle size may become too large.

  The pressure during firing varies depending on the firing temperature or the like, but is usually normal pressure or higher, preferably 0.5 MPa or higher, and is usually 200 MPa or lower, preferably 1 MPa or lower.

  The firing time varies depending on the firing temperature, pressure, and the like, but is usually 10 minutes or longer, preferably 1 hour or longer, and is usually 24 hours or shorter, preferably 6 hours or shorter.

  The atmosphere at the time of firing is not particularly limited, but is basically an inert gas or reducing gas atmosphere. An atmosphere containing a trace amount of oxygen having an oxygen concentration in the range of 0.1 ppm to 10 ppm is preferable because the phosphor can be synthesized at a relatively low temperature. When firing in an oxidizing atmosphere such as in an oxygen-containing gas or in the air where the oxygen concentration exceeds 0.1% by volume, the volatilization of nitrogen from the raw materials and products may increase, making it impossible to obtain the target phosphor There is.

  Specific examples of the inert gas or the reducing gas include nitrogen, hydrogen, argon, ammonia and the like. In addition, only 1 type may be used for an inert gas and reducing gas, and 2 or more types may be used together by arbitrary combinations and a ratio. Among these, in order to prevent the volatilization of nitrogen from raw materials and products, a nitrogen atmosphere is preferable. The nitrogen gas concentration in the nitrogen atmosphere is usually 50% by volume or more, preferably 70% by volume or more, and usually 100% by volume or less, preferably 90% by volume or less.

In addition, although baking may be performed once, you may perform repeatedly over multiple times.

<Flux>
In the firing step, a flux may coexist in the reaction system from the viewpoint of growing good crystals. The type of the flux is not particularly limited, but examples include NH ₄ Cl, LiCl, NaCl, KCl, CsCl, CaCl ₂ , BaCl ₂ , SrCl _{2 and} other chlorides, LiF, NaF, KF, CsF, CaF ₂ , BaF _2. , Fluorides such as SrF ₂ and AlF ₃ . The amount of flux, varies depending on the raw materials of the type and flux materials, ^{M 1} source, Si source, usually 0.01 wt% or more based on the total of Al source and ^{M 2} source, even 0.1 A range of not less than wt%, usually not more than 20 wt%, and more preferably not more than 10 wt% is preferable. If the amount of flux used is too small, the effect of the flux will not appear, and if the amount of flux used is too large, the flux effect will be saturated, or it will be incorporated into the host crystal and change the emission color or cause a decrease in brightness There is. These fluxes may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

(Post-processing)
After the above-described firing step, treatments such as washing, drying, and classification may be performed as necessary.
In addition, when manufacturing the light-emitting device by the method to be described later using the phosphor of the present invention, it is preferable to perform a known surface treatment, for example, calcium phosphate treatment, if necessary, before use.

[3. 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 excellent conversion efficiency with respect to blue light or near-ultraviolet light. For example, a high-efficiency blue-green light emitting device can be realized when used in a light emitting device that emits blue-green light (hereinafter referred to as “blue-green light emitting device” as appropriate). Moreover, a high-performance white light emitting device can be realized by combining a phosphor of the present invention, which is a blue-green phosphor, with a red phosphor, a blue phosphor, an orange phosphor, or the like. The light emitting device thus obtained can be used as a light emitting unit or an illumination device of an image display device.

  Moreover, since the phosphor of the present invention can be excited by ultraviolet rays, electron beams or the like, it can be suitably used not only for LED applications but also for fluorescent lamps, fluorescent lamps and the like.

[4. 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.

[4-1. Phosphor]
There is no restriction | limiting in the kind of fluorescent substance of this invention contained in the fluorescent substance containing composition of this invention, It can select arbitrarily from what was mentioned above. Moreover, the fluorescent substance of this invention contained in the fluorescent substance containing composition of this invention may be only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. Furthermore, the phosphor-containing composition of the present invention may contain a phosphor other than the phosphor of the present invention as long as the effects of the present invention are not significantly impaired.

[4-2. Liquid medium]
The kind of the liquid medium used for the phosphor-containing composition of the present invention is not particularly limited, and a curable material that can be molded over the semiconductor light emitting element can be used. The curable material is a fluid material that is cured by performing some kind of curing treatment. Here, the fluid state means, for example, a liquid state or a gel state. The curable material is not particularly limited as long as it secures the role of guiding the light emitted from the solid light emitting element to the phosphor. Moreover, only 1 type may be used for a curable material and it may use 2 or more types together by arbitrary combinations and a ratio. Therefore, any of inorganic materials, organic materials, and a mixture of both can be used as the curable material.

  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

  On the other hand, examples of the organic material include a thermosetting resin and a photocurable resin. Specific examples include (meth) acrylic resins such as poly (meth) acrylic acid methyl (where “(meth) acrylic” refers to both “acrylic” and “methacrylic”); polystyrene, styrene- Styrene resin such as acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; cellulose resin such as ethyl cellulose, cellulose acetate, cellulose acetate butyrate; epoxy resin; phenol resin; It is done.

  Among these curable materials, it is preferable to use a silicon-containing compound that is less deteriorated with respect to light emitted from the semiconductor light-emitting element and is excellent in alkali resistance, acid resistance, and heat resistance. A silicon-containing compound is a compound having a silicon atom in the molecule, organic materials such as polyorganosiloxane (silicone compounds), inorganic materials such as silicon oxide, silicon nitride, and silicon oxynitride, and borosilicates and phosphosilicates. Examples thereof include glass materials such as salts and alkali silicates. Among these, silicone materials are preferable from the viewpoints of transparency, adhesion, ease of handling, and excellent mechanical and thermal stress relaxation characteristics.

  The silicone-based material usually refers to an organic polymer having a siloxane bond as a main chain, and for example, condensation-type, addition-type, improved sol-gel type, photo-curing type silicone-based materials can be used.

  As the condensed silicone material, for example, semiconductor light-emitting device members described in JP-A-2007-112973 to 112975, JP-A-2007-19459, JP-A-2008-34833, and the like can be used. Condensation-type silicone materials have excellent adhesion to components such as packages, electrodes, and light-emitting elements used in semiconductor light-emitting devices, so the addition of adhesion-improving components can be minimized, and crosslinking is mainly due to siloxane bonds. There is an advantage of excellent heat resistance and light resistance.

  Examples of the addition-type silicone material include potting silicone materials described in JP-A-2004-186168, JP-A-2004-221308, JP-A-2005-327777, JP-A-2003-183881, Organically modified silicone materials for potting described in JP-A-2006-206919, silicone materials for injection molding described in JP-A-2006-324596, silicone materials for transfer molding described in JP-A-2007-231173, etc. Can be suitably used. The addition-type silicone material has advantages such as a high degree of freedom in selection such as a curing speed and a hardness of a cured product, a component that does not desorb during curing, hardly shrinking due to curing, and excellent deep part curability.

  Moreover, as an improved sol-gel type silicone material that is one of the condensation types, for example, the silicone materials described in JP-A-2006-077234, JP-A-2006-291018, JP-A-2007-119569 and the like can be used. It can be used suitably. The improved sol-gel type silicone material has an advantage that it has a high degree of crosslinking, heat resistance, light resistance and durability, and is excellent in the protective function of a phosphor having low gas permeability and low moisture resistance.

  As the photocurable silicone material, for example, silicone materials described in JP 2007-131812 A, JP 2007-214543 A, and the like can be suitably used. The ultraviolet curable silicone material has advantages such as excellent productivity because it cures in a short time, and it is not necessary to apply a high temperature for curing, so that the light emitting element is hardly deteriorated.

These silicone materials may be used alone, or a mixture of a plurality of silicone materials may be used if curing inhibition does not occur when mixed.

[4-3. Content ratio of liquid medium and phosphor]
The content of the liquid medium is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 25% by weight or more, preferably 40% by weight or more, based on the entire phosphor-containing composition of the present invention. The amount is usually 99% by weight or less, preferably 95% by weight or less, more preferably 80% by weight or less. When the amount of the liquid medium is large, no particular problem occurs. However, in order to obtain a desired chromaticity coordinate, color rendering index, luminous efficiency, etc. in the case of a semiconductor light emitting device, it is usually at a blending ratio as described above. It is desirable to use a liquid medium. On the other hand, when there is too little liquid medium, fluidity | liquidity may fall and it may become difficult to handle.

  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 using a silicon-containing compound for the purpose of improving heat resistance, light resistance, etc., other thermosetting resins such as an epoxy resin are contained so as not to impair the durability of the silicon-containing compound. Also good. 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.

  The content of the phosphor in 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 1% by weight or more with respect to the entire phosphor-containing composition of the present invention, Preferably it is 5 weight% or more, More preferably, it is 20 weight% or more, and is 75 weight% or less normally, Preferably it is 60 weight% or less. The proportion of the phosphor of the present invention in the phosphor in the phosphor-containing composition is also arbitrary, but is usually 30% by weight or more, preferably 50% by weight or more, and usually 100% by weight or less. If the phosphor content in the phosphor-containing composition is too high, the flowability of the phosphor-containing composition may be inferior and difficult to handle, and if the phosphor content is too low, the light emission efficiency of the light-emitting device decreases. There is a tendency.

[4-4. Other ingredients]
In the phosphor-containing composition of the present invention, in addition to the phosphor and the liquid medium, other components such as a metal oxide for adjusting the refractive index, a diffusing agent, and a filler are used unless the effects of the present invention are significantly impaired. Further, additives such as a viscosity modifier and an ultraviolet absorber may be contained. Only 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and a ratio.

[5. Light emitting device]
The light-emitting device of the present invention (hereinafter referred to as “light-emitting device” as appropriate) includes a first light-emitting body (excitation light source), and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body. A light-emitting device having the above-described [1. It contains a first phosphor containing one or more of the phosphors of the present invention described in the section [Phosphor].

  Preferable specific examples of the phosphor of the present invention used in the light emitting device of the present invention include [1. Examples thereof include the phosphor of the present invention described in the “Phosphor” column and the phosphors used in the respective Examples in the “Example” column described later. In addition, any one of the phosphors of the present invention may be used alone, or two or more may be used in any combination and ratio.

  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.

  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 as described above, in addition to the phosphor of the present invention as described later. A phosphor emitting blue fluorescence (hereinafter referred to as “blue phosphor” as appropriate), a phosphor emitting green fluorescence (hereinafter referred to as “green phosphor” as appropriate), and a phosphor emitting red fluorescence (hereinafter referred to as “ It is obtained by using a known apparatus configuration using any combination of known phosphors such as “red phosphor” and phosphors emitting yellow fluorescence (hereinafter appropriately referred to as “yellow phosphor”).

  Here, the white color of the white light emitting device means all of (yellowish) white, (greenish) white, (blueish) white, (purple) white and white defined by JIS Z8701. Of these, white is preferred.

[5-1. Configuration of light emitting device]
<5-1-1. 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 emission peak wavelength of the first illuminant is not particularly limited as long as it overlaps with the absorption wavelength of the second illuminant described later, and an illuminant having a wide 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 in 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 blue light is used as excitation light, the emission peak wavelength is usually 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 480 nm or less, preferably 470 nm or less, more preferably 460 nm or less. It is desirable to use a luminescent material having the same. On the other hand, when near-ultraviolet light is used as excitation light, the phosphor of the present invention is excited by blue light from a phosphor that emits blue light when excited by near-ultraviolet light. It is preferable to select excitation light (near ultraviolet light) having a wavelength suitable for the band. Specifically, it is desirable to use a luminescent material 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, preferably 410 nm or less, more preferably 400 nm or less. .

  As the first light emitter, a semiconductor light emitting element is generally used, and specifically, a light emitting diode (LED), a laser diode (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 emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and emit very bright light with low power when combined with the phosphor. It is because it is 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. As the GaN-based LED and LD, those having an Al _X Ga _Y N light emitting layer, a GaN light emitting layer, or an In _X Ga _Y N light emitting layer are preferable. Among them, since the emission intensity is very high, the GaN-based LED is particularly preferably one having an In _X Ga _Y N light emitting layer, and more preferably a multiple quantum well structure having an In _X Ga _Y N layer and a GaN layer. preferable.

  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.

<5-1-2. Second luminous body>
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 one or more phosphors of the present invention are used as the first phosphor. A second phosphor (a blue phosphor, a green phosphor, a yellow phosphor, an orange phosphor, a red phosphor, etc.), which will be described later, is contained 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 host _{crystal, 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, and the like 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.

  Specific examples of preferred crystal matrixes are shown in the following table.

  However, the matrix crystal 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.

<5-1-2-1. First phosphor>
The 2nd light-emitting body in the light-emitting device of this invention contains the 1st fluorescent substance containing the fluorescent substance of the above-mentioned this invention at least. Any one of the phosphors of the present invention may be used alone, or two or more of them may be used in any combination and ratio, and the phosphor of the present invention may have a desired emission color. What is necessary is just to adjust a composition suitably.

  The weight median diameter of the first phosphor used in the light emitting device of the present invention is usually in the range of 2 μm or more, especially 5 μm or more, and usually 30 μm or less, especially 25 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of the dispenser to occur.

<5-1-2-2. 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. 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. For example, when a green phosphor is used as the first phosphor, a phosphor other than a green phosphor such as a blue phosphor, a red phosphor, or a yellow phosphor may be used as the second phosphor. However, a phosphor having the same color as the first phosphor can be used as the second phosphor.

Second phosphor weight-average median diameter D ₅₀ of which is used for the light emitting device of the present invention is usually 2μm or more and preferably 5μm or more, and usually 30μm or less is preferably in a range of inter alia 20μm 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 the weight median diameter is too large, there is a tendency for coating unevenness and blockage of the dispenser to occur.

<Blue phosphor>
When a blue phosphor is used in addition to the phosphor of the present invention, 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. When the emission peak wavelength of the blue phosphor used is within this range, it overlaps with the excitation band of the phosphor of the present invention, and the phosphor of the present invention can be efficiently excited by the blue light from the blue phosphor. Because.
The following table shows phosphors that can be used as such blue phosphors.

Among these, as the blue phosphor, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu, (Ba , Ca, Mg, Sr) ₂ SiO ₄ : Eu, (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu are preferred, and (Ba, Sr) MgAl ₁₀ O ₁₇ : Eu, (Ca, Sr, Ba) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu, Ba ₃ MgSi ₂ O ₈ : Eu are more preferable, and Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, BaMgAl ₁₀ O ₁₇ : Eu is particularly preferable.

  Any one of the blue phosphors exemplified above may be used alone, or two or more 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.
The phosphors that can be used as such green phosphors are shown in the table below.

Among these, as the green phosphor, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, CaSc ₂ O ₄ : Ce, Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce, (Sr, Ba) ₂ SiO ₄ : Eu, (Si, Al) ₆ (O, N) ₈ : Eu (β-sialon), (Ba, Sr) ₃ Si ₆ O ₁₂ N ₂ : Eu, SrGa ₂ S ₄ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Mn is preferable.

When the obtained light-emitting device is used for a lighting device, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, CaSc ₂ O ₄ : Ce, Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce, (Sr , Ba) ₂ SiO ₄ : Eu, (Si, Al) ₆ (O, N) ₈ : Eu (β-sialon), (Ba, Sr) ₃ Si ₆ O ₁₂ N ₂ : Eu are preferable.
When the obtained light emitting device is used for an image display device, (Sr, Ba) ₂ SiO ₄ : Eu, (Si, Al) ₆ (O, N) ₈ : Eu (β-sialon), (Ba, Sr) ₃ Si ₆ O ₁₂ N ₂ : Eu, SrGa ₂ S ₄ : Eu, and BaMgAl ₁₀ O ₁₇ : Eu, Mn are preferable.

  Any one of the green 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.
The phosphors that can be used as such yellow phosphors are shown in the table below.

More in even, as the yellow _{phosphor, Y 3 Al 5 O 12:} Ce, (Y, Gd) 3 Al 5 O 12: Ce, (Sr, Ca, Ba, Mg) 2 SiO 4: Eu, (Ba, Sr) Si ₂ N ₂ O ₂ : Eu is preferred.

  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.

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

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, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu, (La, Y) ₂ O ₂ S: Eu, Eu (dibenzoylmethane) ) ₃ · 1,10-phenanthroline complexes of β- diketone Eu complex, a carboxylic acid Eu _complex, K 2 _SiF 6: Mn is _{preferred, (Ca, Sr, Ba)} 2 Si 5 (N, O) 8: Eu, (Sr, Ca) AlSi (N, O): Eu, (La, Y) ₂ O ₂ S: Eu, and K ₂ SiF ₆ : Mn are more preferable.

As the orange phosphor, (Sr, Ba) ₃ SiO ₅ : Eu, (Sr, Ba) ₂ SiO ₄ : Eu, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, ( Ca, Sr, Ba) AlSi (N, O) ₃ : Ce is preferred.

  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.

[6. Embodiment of Light Emitting Device]
[6-1. 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 denotes a mount lead, reference numeral 6 denotes an inner lead, reference numeral 7 denotes an excitation light source (first light emitter), reference numeral 8 denotes a phosphor-containing portion, reference numeral 9 denotes a conductive wire, reference numeral 10 Indicates 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 portion (second light emitter), reference numeral 24 is a frame, reference numeral 25 is a conductive wire, reference numerals 26 and 27 are electrodes. Respectively.

[6-2. Application of light emitting device]
The use of the light-emitting device of the present invention is not particularly limited, and can be used in various fields in which ordinary light-emitting devices are used. However, since the color rendering property is high and the color reproduction range is wide, the illumination device is particularly preferable. And as a light source for image display devices.

<6-2-1. Lighting device>
When the light-emitting device of the present invention is applied to a lighting device, the above-described light-emitting device may be appropriately incorporated into a known lighting device. For example, a surface-emitting illumination device (11) incorporating the above-described light-emitting device (4) as shown in FIG. 3 can be mentioned.

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

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

<6-2-2. Image display device>
When the light emitting device of the present invention is used as a light source of an image display device, the specific configuration of the image display device is not limited, but it is preferably used 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 this invention is demonstrated still in detail using an Example, this invention is not limited to a following example, unless the summary is exceeded.

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

<Measurement method of emission spectrum>
The emission spectrum was measured using a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a 150 W xenon lamp as an excitation light source and a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus.
Specifically, the light from the excitation light source was passed through a diffraction grating spectrometer having a focal length of 10 cm, and only the excitation light having a wavelength of 405 nm 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.
The emission peak wavelength (hereinafter sometimes referred to as “peak wavelength”) and the half width of the emission peak were read from the obtained emission spectrum.
Relative light emission peak intensity (hereinafter sometimes referred to as “relative peak intensity”) and relative luminance are expressed as relative values with the peak intensity at the time of excitation at 365 nm wavelength of LP-B4 manufactured by Kasei Optonix as a reference value of 100. did. Higher emission peak intensity and relative luminance are preferable.

<Measurement 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 430 nm to 800 nm by a method according to JIS Z8724.

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

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

[Raw materials]
As phosphor raw materials, SrO, Sr ₂ N, SrCO ₃ (made by Rare Metallic), AlN (made by Tokuyama), Si ₃ N ₄ (made by Ube Industries, Ltd.), SiO ₂ (made by Admafine), Eu ₂ O ₃ (manufactured by Rare Metallic), BaO, and CaO were used. SrO, BaO, CaO, and Sr ₂ N were synthesized by the following methods, respectively.
SrCO ₃ (manufactured by Rare Metallic) is used as the SrO raw material, BaCO ₃ (manufactured by Rare Metallic) is used as the BaO raw material, and CaCO ₃ (manufactured by Shirahige Chemical Co.) is used as the CaO raw material. SrCO ₃ and BaCO ₃ Was calcined at 1200 ° C. and CaCO ₃ was 1000 ° C. at atmospheric pressure for 5 hours, respectively.
Sr ₂ N was obtained by baking Sr metal (manufactured by Aldrich) at 600 ° C. for 8 hours in a nitrogen atmosphere. These samples were stored in a glow box filled with nitrogen.

[Example 1]
SrCO ₃ is 0.84 g, AlN is 0.31 g, Si ₃ N ₄ is 0.74 g, SiO ₂ is 0.05 g, and Eu ₂ O ₃ is 0.00 so that the charged composition becomes the composition ratio shown in Table 6. Weighed 06 g with an electronic balance. After weighing, all of these raw material powders were put in an alumina mortar, ground and mixed until uniform. The operations of weighing, grinding and mixing were performed in a glove box filled with N ₂ gas.

The obtained mixed powder was filled in a boron nitride crucible (BN crucible) as it was. This BN crucible was placed in a resistance heating type vacuum heat treatment furnace (manufactured by Fuji Denpa Kogyo). Then, after reducing the pressure to 5 × 10 ⁻³ Pa or less, vacuum heating was performed from room temperature to 800 ° C. at a heating rate of 20 ° C./min. When the temperature reached 800 ° C., high-purity nitrogen gas (99.9995%) was introduced for 30 minutes until the pressure in the furnace reached 0.92 MPa. After the introduction of the high purity nitrogen gas, the temperature was further increased to 1200 ° C. at a temperature increase rate of 20 ° C./min while maintaining 0.92 MPa. While maintaining at 1200 ° C. for 5 minutes, the thermocouple was changed to a radiation thermometer and further heated to 1800 ° C. at a temperature rising rate of 20 ° C./min. When the temperature reached 1800 ° C., the temperature was maintained for 2 hours, and further heated to 1900 ° C. at 20 ° C./min, and maintained at that temperature for 2 hours. After firing, the mixture was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, and then allowed to cool.

  The X-ray diffraction pattern of the obtained phosphor is shown in FIG. This diffraction pattern was an unknown X-ray diffraction pattern not described in PDF. At this time, since a single crystal was observed in the sample, the single crystal structure analysis was performed using RAXIS-RAPID manufactured by Rigaku Corporation as described later, and the coordinates of each atom were determined. Further, an X-ray diffraction pattern was simulated based on the coordinates, and the chemical composition of the phosphor of the present invention was determined.

  Table 7 shows the measurement results of the emission characteristics of the obtained phosphor under 405 nm excitation irradiation.

  Further, FIG. 5 shows an emission spectrum of this phosphor under irradiation with excitation at 405 nm. An emission spectrum having an emission peak wavelength of 490 nm and a half width of 97 nm was observed.

  The half width of the phosphor obtained in Example 1 was larger than the half width (70 nm) of the phosphor obtained in Comparative Example 1 described later. In the crystal structure of the phosphor of the present invention, where Eu is substituted for Sr as the emission center, stacking fraud is likely to occur, and many different environments of Eu are generated in the crystal structure and can be emitted from various environments. It is considered that broad emission with a wide half-value width was obtained by combining the emission of Eu.

  Next, the phosphor obtained in Example 1 is analyzed for chemical composition and crystal structure as follows, and has the above-described crystal phase A, and the crystal phase A is a superstructure. confirmed.

<Measurement of single crystal X-ray diffraction method>
The X-ray diffraction intensity of the single crystal was measured and integrated at room temperature using Rigaku RAXIS-RAPID II (X-ray source: MoKα 0.71075Å). Based on the analysis of the obtained diffraction data, an attempt was made to derive a structural model as a monoclinic system (P1) by analysis software (Superflip). Although an almost correct unit model was obtained, the diffraction intensity data could not be fully explained.

<Measurement of electron diffraction and view of lattice image>
Therefore, electron diffraction was performed in order to confirm the streak distribution observed in the diffraction data and the symmetry of the lattice. Ten or more transparent plate-like single crystals (0.3 mm to 0.5 mm) in the sample powder were picked up and lightly pulverized in an agate mortar. After this pulverized piece was dispersed in alcohol, it was scraped on a micro Cu grid for TEM to which a collodion film was applied.
With a 200 kV transmission electron microscope (JEOL, JEM-2000EX), an electron beam diffraction pattern of a crystal piece sample was photographed, and when an electron beam was incident from a specific direction, reflection of an odd number of h and l with a Miller index hkl Diffuse strikes were observed in the direction of the axis (b-axis) of the 37.7 cm period. Furthermore, stripe-like contrasts with different widths due to stacking faults were observed from the crystal orientation where Diffuse strikes were observed by electron diffraction.
This shows that the stacking fault is in (010). It can also be seen that the phosphor obtained in Example 1 has a superstructure (modulation structure).

<Chemical composition analysis of single crystal>
Before structural analysis, single crystal was analyzed by EDX analysis using a scanning electron microscope (Hitachi High-Technologies Corporation, S-3400N) attached with an energy dispersive X-ray analyzer (EMAX ENERGY) manufactured by Horiba, Ltd. The chemical composition was determined.
For each of the four crystal samples deposited with carbon, 40 points of each crystal were analyzed and averaged. As a result of analysis, there is no great difference in any crystal, and the molar ratio of Sr: Eu: Al: Si is 0.94 (2): 0.06 (1): 1.19 (3): 2.81 ( 5) (Note that the numbers in parentheses represent standard deviations). Also, characteristic X-ray peaks of N and O were detected, and the molar ratio of N and O was approximately 4: 1. Therefore, the crystal structure analysis was performed with the composition formula of (Sr _0.94 Eu _0.06 ) (Al _0.3 Si _0.7 ) ₄ (N _0.8 O _0.2 ) ₆ .

<Crystal structure analysis>
From the measurement result of electron diffraction, the obtained phosphor crystal is a face-centered lattice (F lattice a = 5.8055 (6), b = 37.764 (4), c = 9.5910 (10) Å)). In at least the b-axis direction and the a-axis direction, the extinction rule is recognized when the Miller index is 0 kl and k = 4n, and when the Miller index is 00l and l = 4n. The extinction law was confirmed when h = 4n with the Miller index h00. From these things, the possibility that the space group was either Fdd2 (Fd2d, F2dd) or Fddd was considered. The space group from which the crystal structure model can be obtained is Fdd2, and Table 8 summarizes the analysis results.

  From the above results, it can be seen that the finished composition of the phosphor of the present invention is based on the charged composition.

[Comparative Example 1]
As phosphor raw materials so as to have the charged composition shown in Table 9, 0.55 g of Sr ₂ N, 0.24 g of AlN, 1.09 g of Si ₃ N ₄ , 0.12 g of SiO ₂ , Eu ₂ O ₃ A phosphor was produced under the same conditions as in Example 1 except that 0.01 g was used.

The X-ray diffraction pattern of the obtained phosphor is shown in FIG. The X-ray diffraction pattern of this phosphor could be identified as the Sr ₃ Si ₁₃ Al ₃ O ₂ N ₂₁ phase reported by Toshiba Fukuda et al. In addition, Table 10 shows the measurement results of the emission characteristics of the obtained phosphor under excitation at 405 nm.
Moreover, the emission spectrum of this phosphor under 405 nm excitation is shown in FIG. The emission peak wavelength was 500 nm, and a peak was observed on the longer wavelength side compared to the example.

[Example 2]
As phosphor materials, 0.72 g of SrO, 0.36 g of AlN, 0.86 g of Si ₃ N ₄ , 0.05 g of SiO ₂ , 0.05 g of Eu ₂ O so that the charged composition becomes the composition ratio shown in Table 11. _A phosphor was produced under the same conditions as in Example 1 except that 0.012 g of ₃ was used. In this example, SrO was used as the Sr source instead of SrCO ₃ in Example 1.

  The X-ray diffraction pattern of the obtained phosphor is shown in FIG. This diffraction pattern was an unknown X-ray diffraction pattern not described in PDF. Based on the single crystal structure analysis result (shown in Table 8 above) performed in Example 1, the obtained phosphor is subjected to phase identification, and is a substance having a chemical composition represented by Formula [1]. It was identified.

  Table 12 shows the measurement results of the emission characteristics when the obtained phosphor was excited at 405 nm.

Further, FIG. 9 shows an emission spectrum of this phosphor under excitation at 405 nm. From FIG. 9, it was revealed that blue light emission having a peak at 474 nm was exhibited.
Further, FIG. 10 shows an excitation spectrum when this phosphor is monitored at an emission peak wavelength of 474 nm. An excitation spectrum that was tailed down to a long wavelength of 450 nm was observed.

[Examples 3 to 15]
A phosphor was manufactured under the same conditions as in Example 1 except that the phosphor material shown in Table 13 was weighed in the amount shown in Table 13 so as to have the charged composition shown in Table 13. Note that SrO was used as the Sr source. For example, in Example 3, 0.72 g of SrO, 0.36 g of AlN, 0.86 g of Si ₃ N ₄ , 0.05 g of SiO ₂ and 0.006 g of Eu ₂ O ₃ were used. In Table 13, the Eu concentration indicates the Eu concentration with respect to the Sr site.

  The X-ray diffraction patterns of the phosphors obtained in Examples 3, 6, 10, and 15 are shown in FIG. In Examples 3, 6, 10, and 15, it was confirmed that the phosphor of the present invention (the substance having the composition represented by the formula [1]) was generated as the main phase.

  Table 14 shows the measurement results of the light emission characteristics when the obtained phosphor was excited at 405 nm.

  In addition, FIG. 12 shows emission spectra of the phosphors of Examples 3, 6, 10, and 15 under excitation at 405 nm.

  When the Eu substitution amount in Example 6 was 6 atm%, the emission intensity was maximized. It was also observed that the emission wavelength shifted to the longer wavelength side when the Eu concentration was increased. The emission peak wavelengths were, for example, 467 nm in Example 3, 491 nm in Example 6, 501 nm in Example 10, and 517 nm in Example 15.

[Examples 16 to 21]
Phosphors under the same conditions as in Example 1 except that SrO, BaO, AlN, Si ₃ N ₄ , SiO ₂ , and Eu ₂ O ₃ were weighed so that the charged composition had the composition ratio shown in Table 15. Manufactured. For example, in Example 16, 0.632 g of SrO, 0.053 g of BaO, 0.351 g of AlN, 0.841 g of Si ₃ N ₄ , 0.051 g of SiO ₂ and 0.072 g of Eu ₂ O ₃ were used. .

  The X-ray diffraction pattern of the obtained phosphor is shown in FIG. From the result of this X-ray diffraction measurement, when the Ba substitution amount is 10 atm% or less with respect to the Sr site (that is, in Examples 16 and 17), the phosphor phase represented by the formula [1] is observed. It was confirmed that In Example 18, when the Ba substitution amount was 25 atm%, a mixed phase containing the phosphor phase and the other phases was observed. Furthermore, when the Ba substitution amount was set to 50 atm% or more in Examples 19 to 21, a new crystal phase B different from the crystal phase A was confirmed.

  Table 16 shows the measurement results of the light emission characteristics when the obtained phosphor was excited at 405 nm. Further, FIG. 14 shows an emission spectrum under excitation at 405 nm.

  From Table 16 or FIG. 14, it was found that when the Ba substitution amount is 25 atm%, emission peak wavelengths appear at 481 nm and 651 nm, and when the Ba substitution amount is 50 atm% or more, red emission having a peak at 659 nm is exhibited.

[Examples 22 to 25]
The same conditions as in Example 1 except that SrO, CaO, AlN, Si ₃ N ₄ , SiO ₂ , Eu ₂ O ₃ were weighed as phosphor raw materials so as to have the composition ratio shown in Table 17. A phosphor was manufactured. For example, in Example 22, 0.64 g of SrO, 0.02 g of CaO, 0.36 g of AlN, 0.86 g of Si ₃ N ₄ , 0.05 g of SiO ₂ and 0.07 g of Eu ₂ O ₃ It was.

  The X-ray diffraction pattern of the obtained phosphor is shown in FIG. According to the X-ray diffraction results, the presence of the crystal phase A was observed when the Ca substitution amount was 5 atm% or less and 10 atm% or less with respect to Sr (Sr site), respectively (Examples 22 and 23).

  Table 18 shows the measurement results of the light emission characteristics when the obtained phosphor was excited at 405 nm. Further, FIG. 16 shows an emission spectrum under excitation at 405 nm.

The emission peaks in Examples 22 and 23 under irradiation of 405 nm were confirmed at about 490 to 500 nm.
In the Ca substitution amount of 25 atm% in Example 24, the Sr _3.44 Ca _1.07 Si _13.12 Al _2.88 N _20.14 O _4.87 phase described in Non-Patent Document 1 reported by Kechel et al. 15 was confirmed from FIG. 15, and the formation of the crystal phase A was not confirmed. That is, a new crystal phase (hereinafter referred to as “crystal phase C”) was confirmed as the phosphor. From FIG. 16, the peak wavelength of the emission spectrum in Example 24 was observed at 533 nm. Even when the amount of Ca substitution in Example 25 was 50 atm%, only the crystal phase C was observed by powder X-ray diffraction measurement, but yellow emission was observed in the emission spectrum, and the presence of α-sialon phase was confirmed. It was.

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)
DESCRIPTION OF SYMBOLS 8 Fluorescent substance containing part 9 Conductive wire 10 Mold member 11 Surface light-emitting illuminating device 12 Holding case 13 Light-emitting device 14 Diffusion plate 22 Excitation light source (1st light-emitting body)
23 Phosphor-containing part (second light emitter)
24 Frame 25 Conductive wire 26, 27 Electrode

Claims (7)

A phosphor having a composition represented by the following formula [1].
^{_{M 1 n (1-y)}} Al nx + z Si 16- (nx + z) O nx + z N 20 + n- (nx + z): M 2 y ··· [1]
(In the above formula [1], M ¹ represents at least one divalent metal element selected from the group consisting of Sr, Ba, Ca, Mg, and Zn, and M ² represents Cr, Mn, Ce, Pr, At least one type of activating element selected from the group consisting of Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb is shown.
Moreover, x, y, z, and n show the numerical value of the following ranges, respectively.
0 ≦ x ≦ 1
0 <y ≦ 1
0 ≦ z ≦ 13
3.6 ≦ n ≦ 4.4)   The phosphor according to claim 1, wherein the phosphor has a superstructure. 3. The phosphor according to claim 1, comprising a crystal phase A defined below.
In an X-ray diffractometer using a CuKα X-ray source, a crystal phase in which a diffraction peak is observed in a diffraction angle (2θ) range of 27 ° to 29 ° (R0), which is based on the diffraction peak (P0) As diffraction peaks, the five diffraction peaks derived from the black angle (θ0) of P0 are designated as P1, P2, P3, P4, and P5 in order from the low angle, and the diffraction angle ranges of these diffraction peaks are defined as R1, R2, R1, R2, R3, R4 and R5 are R3, R4 and R5, respectively.
R1 = R1s-R1e
R2 = R2s-R2e
R3 = R3s-R3e
R4 = R4s-R4e
R5 = R5s-R5e
An angle range of at least one diffraction peak in all ranges of R1, R2, R3, R4, and R5,
In addition, among P1, P2, P3, P4, and P5, the intensity of P0 has a diffraction peak height ratio of 20% or more with respect to the height of the diffraction peak having the highest diffraction peak height. Yes,
Among P1, P2, P3, P4, and P5, the peak intensity of at least one of P1, P2, P3, P4, and P5 other than P1, P2, P3, P4, and P5 with respect to the height of the diffraction peak having the highest diffraction peak height Has a diffraction peak height ratio of 5% or more.
Here, when there are two or more diffraction peaks in each angular range of the angular ranges R0, R1, R2, R3, R4, and R5, the peak having the highest peak intensity among these is P0, P1, Let P2, P3, P4 and P5.
R1s, R2s, R3s, R4s, and R5s indicate start angles of R1, R2, R3, R4, and R5, respectively. R1e, R2e, R3e, R4e, and R5e are R1, R2, R3, and R5e, respectively. The end angles of R4 and R5 are shown, and specifically the following angles are shown.
R1s: 2 × arcsin {sin (θ0) / (0.943 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (0.943 × 0.985)}
R2s: 2 × arcsin {sin (θ0) / (0.912 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (0.912 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (0.869 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (0.869 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.834 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.834 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.731 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.731 × 0.985)}   A phosphor-containing composition comprising the phosphor according to any one of claims 1 to 3 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,
The light emitting device, wherein the second light emitter contains one or more of the phosphors according to any one of claims 1 to 3 as a first phosphor.   An image display device comprising the light-emitting device according to claim 5 as a light source.   An illumination device comprising the light-emitting device according to claim 5 as a light source.

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