WO2013108782A1

WO2013108782A1 - Oxynitride-based phosphor and light emitting device using same

Info

Publication number: WO2013108782A1
Application number: PCT/JP2013/050668
Authority: WO
Inventors: 文孝吉村; 岳史田原
Original assignee: 三菱化学株式会社
Priority date: 2012-01-17
Filing date: 2013-01-16
Publication date: 2013-07-25
Also published as: JP2013213191A; TW201335338A

Abstract

Provided is a phosphor which has a skeletal structure configured of Si, Al, N and O and has high luminous intensity. An oxynitride-based phosphor which is characterized by containing a crystalline phase that has a composition represented by formula (1): (A_1-x,Eu_x)_aD_bE_cN_dO_e. (In formula (1), A represents alkaline earth metal elements essentially including Sr and Ca; D represents tetravalent metal elements essentially including Si; E represents trivalent metal elements essentially including Al; x represents a number that satisfies 0.0001 ≤ x ≤ 0.20; and a, b, c, d and e respectively represent numbers that satisfy 0.7 ≤ a ≤ 1.3, 2.8 ≤ b ≤ 4.0, 1.0 ≤ c ≤ 3.0, 4.0 ≤ (b + c)/a ≤ 6.0, 5.0 ≤ d ≤ 7.0, 0 < e ≤ 2.0 and 6.5 ≤ (d + e)/a ≤ 7.5.) The oxynitride-based phosphor is also characterized in that: the crystal system of the crystalline phase is an orthorhombic system or a monoclinic system; and the unit cell volume (V) of the crystalline phase as calculated from the lattice constant is from 1,220 × 10⁶ pm³ to 1,246 × 10⁶ pm³ (inclusive).

Description

Oxynitride phosphor and light emitting device using the same

The present invention relates to an oxynitride phosphor and a light-emitting device using the same.

Fluorescent substances are used in fluorescent display tubes (VFD), field emission displays (FED), plasma display panels (PDP), cold cathode tubes (CRT), light emitting devices (LEDs), and the like. In any of these applications, in order to cause the phosphor to emit light, it is necessary to supply energy for exciting the phosphor to the phosphor. The phosphor is excited by an excitation source having high energy such as vacuum ultraviolet rays, ultraviolet rays, electron beams, blue light, and emits visible light.

In recent years, there has been a demand for a light emitting device that emits white light with high color rendering and color reproducibility. To achieve this, conventional silicate phosphors, phosphate phosphors, aluminate phosphors, sulfides are required. In addition to phosphors such as nitride phosphors, nitride phosphors and oxynitride phosphors are also being searched for.

For example, Sr ₂ Al ₃ Si ₇ ON ₁₃ : Eu, SrAl _1.25 Si _3.75 O _0.25 N _6.75 : Eu, SrAlSi ₄ N are one of the oxynitride phosphors that are attracting attention. ₇ : Phosphors having a composition typified by Eu have been reported (Patent Documents 1 to 4).

JP 2010-106127 A International Publication No. 2007/037059 Pamphlet Special table 2010-518194 gazette JP 2011-195688 A

Here, although the crystal structure of the phosphor described in Patent Document 1 is disclosed, no study has been made on the size of the crystal lattice and the effect of element substitution, and high emission intensity can be obtained. Therefore, further improvement in emission intensity is required for practical use.
In addition, the phosphor described in Patent Document 2 discloses a specific example in which the Sr site is replaced with Ba, but the effect has not been sufficiently studied, and the relationship with the crystal structure has not been studied at all. Not.
Further, although Patent Document 3 discloses that the emission wavelength can be lengthened by substituting the Sr site with Ca, there is no disclosure of specific examples of substituting with Ca, and the size of the crystal lattice due to Ca substitution. There is no suggestion of any change in light emission or improvement in emission intensity.
Further, although the phosphor described in Patent Document 4 described above has improved the emission intensity, it is still insufficient in practical use, and repeated firing is required to obtain a single phase. The manufacturing cost may be high.

Thus, the phosphors described in Patent Documents 1 to 4, that is, phosphors having a skeletal structure composed of Si, Al, N, and O and having a crystal structure in which Sr sites exist in the voids. The improvement of the emission intensity was desired.
An object of the present invention is to improve the emission intensity of a phosphor having a skeleton structure composed of Si, Al, N, and O and having a crystal structure in which Sr sites exist in the voids.

As a result of various studies to achieve the above-mentioned problems, the inventors of the present invention are excellent in terms of emission intensity of oxynitride phosphors whose unit cell volume of the crystal phase is in a specific range. As represented by the general formula [1], it has been found that when Ca is essential among the alkaline earth metal elements, the emission intensity is further improved. The present invention has been accomplished based on these findings.

That is, the gist of the present invention includes the phosphor of the following first embodiment.
[1] The following formula [1]:
(A _1-x , Eu _x ) _a D _b E _c N _d O _e [1]
(In the formula [1], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d, and e represent 0.7 ≦ a ≦ 1.3 and 2.8 ≦ b ≦, respectively. 4.0, 1.0 ≦ c ≦ 3.0, 4.0 ≦ (b + c) /a≦6.0, 5.0 ≦ d ≦ 7.0, 0 <e ≦ 2.0, 6.5 ≦ (D + e) /a≦7.5 represents a crystal phase having a composition represented by the formula), and the crystal system of the crystal phase is orthorhombic or monoclinic, and from the lattice constant The calculated unit cell volume (V) of the crystal phase is 1220 × 10 ⁶ pm ³ or more and 1246 × 10 ⁶ pm ³ or less.
[2] The phosphor according to [1], wherein the space group of the crystal phase is Pna2 ₁ .
[3] The phosphor according to [1] or [2], wherein, in the formula [1], a ratio of Ca to the entire element A is 0.001 mol% or more and 80 mol% or less.
[4] The phosphor according to any one of [1] to [3], wherein the emission peak exists in a wavelength range of 550 nm to 650 nm.
The gist of the present invention includes the phosphor of the second embodiment described below.
[5] The following formula [1]:
(A _1-x , Eu _x ) _a D _b E _c N _d O _e [1]
(In the formula [1], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d, and e represent 0.7 ≦ a ≦ 1.3 and 2.8 ≦ b ≦, respectively. 4.0, 1.0 ≦ c ≦ 3.0, 4.0 ≦ (b + c) /a≦6.0, 5.0 ≦ d ≦ 7.0, 0 <e ≦ 2.0, 6.5 ≦ (D + e) /a≦7.5). The crystal phase of the crystal phase is orthorhombic or monoclinic, and the emission peak is An oxynitride phosphor having a wavelength in the range of 581 nm to 650 nm.
[6] The phosphor according to [5], wherein the space group of the crystal phase is Pna2 ₁ .
[7] The phosphor according to [5] or [6], wherein, in the formula [1], a ratio of Ca to the entire element A is 0.001 mol% to 80 mol%.
The gist of the present invention includes the phosphor of the following third embodiment.
[8] The following formula [2]:
(A _1-x , Eu _x ) _a D _b E _c N _d O _e [2]
(In the formula [2], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d, and e represent 0.7 ≦ a ≦ 1.3 and 2.8 ≦ b ≦, respectively. 3.6, 1.0 ≦ c ≦ 3.0, 4.0 ≦ (b + c) /a≦6.0, 5.0 ≦ d ≦ 7.0, 0 <e ≦ 2.0, 6.5 ≦ (D + e) /a≦7.3 is included.) The ratio of Ca to element A in the above [2] is 0.001 mol% or more and 80 mol% or less. The crystal system of the crystal phase is orthorhombic or monoclinic.
[9] The phosphor according to [8], wherein the space group of the crystal phase is Pna2 ₁ .
[10] The phosphor according to [8] or [9], wherein the emission peak exists in a wavelength range of 570 nm to 600 nm.
[11] The phosphor according to any one of [1] to [10], wherein the half width of the emission peak is 95 nm or more.
Moreover, the gist of the present invention includes the phosphor-containing composition, the light emitting device, the lighting device, and the image display device of the following embodiment.
[12] A phosphor-containing composition, wherein at least one phosphor according to any one of [1] to [11] is dispersed in a liquid medium.
[13] A light-emitting device having a first light emitter (excitation light source) and a second light emitter capable of emitting visible light by converting light from the first light emitter, The second light emitter contains at least one of the phosphors according to any one of [1] to [11] as the first phosphor, or the second light emitter according to [12] A light emitting device comprising the phosphor-containing composition described above.
[14] The light emitting device according to [13], wherein the second phosphor includes at least one phosphor having a light emission peak wavelength different from that of the first phosphor as the second phosphor. apparatus.
[15] The light emitting device according to [13] or [14], wherein the correlated color temperature is 2600K to 4500K.
[16] An illumination device or an image display device comprising the light-emitting device according to any one of [13] to [15].

According to the present invention, it is possible to improve the light emission intensity of a phosphor having a skeletal structure composed of Si, Al, N, and O and having a crystal structure in which Sr sites exist in the voids. Furthermore, the phosphor of the present invention hardly produces an impurity phase and can be easily manufactured. In addition, when the phosphor of the present invention is combined with an LED or the like, a light emitting device having excellent light emission characteristics can be provided.

It is a perspective view which shows typically one embodiment of the light-emitting device of this invention. It is sectional drawing which shows another embodiment of the light-emitting device of this invention typically. 2A shows a bullet-type light emitting device, and FIG. 2B shows a surface-mounted light-emitting device. It is sectional drawing which shows typically the one aspect | mode of the illuminating device of this invention. It is an X-ray diffraction pattern obtained by powder X-ray diffraction for the phosphors of Examples 2, 3, 6, 10 and Comparative Example 1. 3 is an emission spectrum of the phosphors of Examples 2, 3, 6 to 9, 13 and Comparative Example 1. 3 is an excitation spectrum of the phosphor of Example 2. It is an X-ray diffraction pattern obtained by powder X-ray diffraction for the phosphors of Examples 4 and 11 and Comparative Example 2. It is an emission spectrum of the phosphors of Examples 4 and 11 and Comparative Example 2. It is an emission spectrum of Examples 5 and 12 and Comparative Example 3. 6 is a powder X-ray pattern obtained by powder X-ray diffraction for the phosphors of Examples 18 to 23. FIG. It is an emission spectrum of the phosphors of Examples 18 to 23. 6 is a powder X-ray pattern obtained by powder X-ray diffraction for the phosphors of Examples 18 and 24-28. 7 is an emission spectrum of the phosphors of Examples 18 and 24 to 28.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention. In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value. 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 “(Ca, Sr, Ba) Al ₂ O ₄ : Eu” has “CaAl ₂ O ₄ : Eu”, “SrAl ₂ O ₄ : Eu”, and “BaAl ₂ O ₄ : Eu”. “Ca _1-x Sr _x Al ₂ O ₄ : Eu”, “Sr _1-x Ba _x Al ₂ O ₄ : Eu”, “Ca _1-x Ba _x Al ₂ O ₄ : Eu”, _{_{_{"Ca 1-x-y Sr x}}} Ba y Al 2 O 4: Eu " (. in the formula, 0 <x <1,0 <y <1,0 < a x + y <1) all the comprehensive It shall be shown in

[1. Phosphor]
<Crystal structure>
The phosphors of the first to third embodiments of the present invention have a skeletal structure composed of Si, Al, N, and O, and have a crystal structure in which Sr sites exist in the voids.

(Crystal system)
The crystal system of the crystal phase contained in the phosphor according to the first to third embodiments of the present invention is orthorhombic or monoclinic, and is preferably orthorhombic.

The phosphors according to the first to third embodiments of the present invention preferably have a crystal structure similar to that of SrAlSi ₄ N _7, and the crystal phase space group is “International Tables for Crystallography (Third, revised edition)”. No. 62 [Pnma], 33 [Pna2 ₁ ], 19 [P2 ₁ 2 ₁ 2 ₁ ], 7 [Pc], or 4 [P2 ₁ ] based on “Volume A Space-Group Symmetry” And those belonging to No. 33 [Pna2 ₁ ] are most preferred.
The space group can be uniquely determined by electron diffraction or convergent electron diffraction.

(Lattice volume of crystal phase)
The phosphor according to the first embodiment of the present invention contains a crystal phase whose unit cell volume (V) calculated from the lattice constant is 1220 × 10 ⁶ pm ³ or more and 1246 × 10 ⁶ pm ³ or less. When the unit cell volume is in the above range, distortion of the skeleton structure caused by introducing the activator can be suppressed, and stable energy transfer is possible, so that the emission intensity is improved.

As described above, the unit cell volume (10 ⁶ pm ³ ) calculated from the lattice constant of the crystal phase contained in the phosphor of the first embodiment of the present invention is usually 1220 or more and 1246 or less, preferably It is 1224 or more, more preferably 1228 or more, further preferably 1232 or more, further preferably 1236 or more, particularly preferably 1240 or more, and preferably 1245 or less, more preferably 1244 or less.

If the unit cell volume is too large, the emission intensity will decrease. Conversely, if the unit cell volume is too small, the skeletal structure will become unstable and impurities of another structure will be produced as a by-product. It tends to cause a decline.

The means for realizing the unit cell volume of the crystal phase contained in the phosphor according to the first embodiment of the present invention is that Sr and Ca are contained in the voids (Sr sites) formed by the open holes in the planar skeleton structure. It is preferable to introduce at a constant ratio, but other atoms having an ionic radius smaller than Sr, such as Mg and Li, may be introduced in addition to Sr and Ca. It is also preferable to adjust the unit cell volume by leaving defects at the Sr site. It is also possible to construct an appropriate skeleton structure by introducing both small atoms or defects such as Li that have a large effect on reducing the skeletal structure and large atoms such as Ba that have the effect of increasing the skeleton structure. is there. Furthermore, when there are two or more types of Sr sites, it is also preferable to appropriately select the type and ratio of atoms or defects to be introduced according to the coordination number, coordination distance, etc. of the sites.
For the same reason as described above, the phosphors of the second to third embodiments of the present invention preferably satisfy the requirements for the unit cell volume (V).

(Lattice constant)
As for the lattice constant (pm) of the crystal phase contained in the phosphor according to the first to third embodiments of the present invention, the a-axis is usually 1162 or more, preferably 1164 or more, more preferably 1166 or more, and usually 1178. Hereinafter, it is preferably 1172 or less, more preferably 1168 or less. Further, the b-axis is usually 2115 or more, preferably 2125 or more, more preferably 2135 or more, particularly preferably 2137.5 or more, and usually 2165 or less, preferably 2155 or less, more preferably 2145 or less.

The phosphor according to the first to third embodiments of the present invention has a planar skeletal structure with a hole extending on a plane including the a-axis and the b-axis, and the planar skeletal structure is c-axis. A skeletal structure is formed by stacking in the direction. Therefore, when the lattice constants of the a axis and the b axis are the above values, particularly the distortion of the planar skeleton structure can be suppressed, and the emission intensity is improved. The c-axis is not particularly limited, but is usually 494 or more, preferably 494.5 or more, more preferably 495.5 or more, particularly preferably 496.5 or more, usually 499.5 or less, preferably 498.5 or more, More preferably, it is 497.5 or less.

(Powder X-ray diffraction pattern)
The phosphors of the first to third embodiments of the present invention preferably contain a crystal phase exhibiting the following powder X-ray diffraction (XRD) pattern.
The crystal phase of the phosphor of the first to third embodiments of the present invention has a diffraction angle (2θ) in the range of 31.0 ° to 31.9 ° (R0) in X-ray diffraction measurement using a CuKα X-ray source. ) Is a crystal phase in which at least one diffraction peak is observed, and a diffraction peak having the highest height among the diffraction peaks is defined as a reference diffraction peak (P0), and is derived from a Bragg angle (θ0) of P0. Two diffraction peaks are designated as P1, P2, P3, P4 and P5 in this order from the low angle side, and when the diffraction angle angle range of these diffraction peaks is R1, R2, R3, R4 and R5, R1, R2 , R3, R4 and R5 are each
R1 = R1s to R1e,
R2 = R2s to R2e,
R3 = R3s to R3e,
R4 = R4s to R4e,
R5 = R5s to R5e,
At least one diffraction peak in all ranges of R1, R2, R3, R4, and R5, and among P0, 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 peak intensity of at least one or more is a diffraction peak height ratio, usually 5% or more, preferably 10% or more, more preferably 15% or more, and particularly preferably 20% or more of a crystal phase, P1, P2, P3 , P4 Is 5% or more crystalline phases at least one or more peak intensity diffraction peak height ratio of P5.

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 peaks having the highest peak intensity among these are P0, P1 respectively. , P2, P3, P4 and P5.

R1s, R2s, R3s, R4s, and R5s are the start angles of R1, R2, R3, R4, and R5, and R1e, R2e, R3e, R4e, and R5e are R1, R2, R3, R4, and R5, respectively. The end angle is shown, and the following angles are shown.

R1s: 2 × arcsin {sin (θ0) / (1.268 × 1.015)}
R1e: 2 × arcsin {sin (θ0) / (1.268 × 0.985)}
R2s: 2 × arcsin {sin (θ0) / (1.037 × 1.015)}
R2e: 2 × arcsin {sin (θ0) / (1.037 × 0.985)}
R3s: 2 × arcsin {sin (θ0) / (1.023 × 1.015)}
R3e: 2 × arcsin {sin (θ0) / (1.023 × 0.985)}
R4s: 2 × arcsin {sin (θ0) / (0.882 × 1.015)}
R4e: 2 × arcsin {sin (θ0) / (0.882 × 0.985)}
R5s: 2 × arcsin {sin (θ0) / (0.788 × 1.015)}
R5e: 2 × arcsin {sin (θ0) / (0.788 × 0.985)}

The phosphor of the present invention includes a phosphor having a yellow to red emission color (first embodiment), a phosphor having an orange to red emission color (second embodiment), which will be described below. And a phosphor having a light emission color of yellow to orange (third embodiment).

<Composition of phosphor>
The phosphor according to the first embodiment of the present invention has the following formula [1]:
(A _1-x , Eu _x ) _a D _b E _c N _d O _e [1]
(In the formula [1], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d, and e represent 0.7 ≦ a ≦ 1.3 and 2.8 ≦ b ≦, respectively. 4.0, 1.0 ≦ c ≦ 3.0, 4.0 ≦ (b + c) /a≦6.0, 5.0 ≦ d ≦ 7.0, 0 <e ≦ 2.0, 6.5 ≦ It includes a crystal phase having a composition represented by (d + e) /a≦7.5.

As described above, in the above formula [1], “A” represents an alkaline earth metal element in which Sr and Ca are essential. The ratio of Sr and Ca to the entire A element is preferably 50 mol% or more, more preferably 70 mol% or more, and particularly preferably 90 mol% or more. In addition to Sr and Ca, the element A may contain an alkaline earth metal element such as barium (Ba).

In the formula [1], the ratio of Ca with respect to the entire element A is a number that usually satisfies 0.001 mol% or more and 80 mol% or less, preferably 0.01 mol% or more, more preferably 1 mol% or more, More preferably 5 mol% or more, particularly preferably 7 mol% or more, most preferably 9 mol% or more, preferably 65 mol% or less, more preferably 50 mol% or less, more preferably 35 mol% or less. Especially preferably, it is 20 mol% or less.
When the proportion of Ca is in the above range, the lattice volume becomes a more appropriate size, and the skeletal structure can take a stable state without distortion.

In the above formula [1], “Eu” represents an activator element that requires europium. Europium (Eu), which is an activator, includes chromium (Cr), manganese (Mn), iron (Fe), cerium (Ce), praseodymium (Pr), neodymium (Nd), and samarium (Sm) as other activators. ), Terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm) and ytterbium (Yb) may be substituted with at least one metal element. . Among these other activators, at least one metal element selected from the group consisting of Ce, Pr, Sm, Tb, and Yb is preferable, and Ce is more preferable in terms of emission quantum efficiency.

The ratio of europium (Eu) to the whole activator element is preferably 50 mol% or more, more preferably 70 mol% or more, and particularly preferably 90 mol% or more.

In the above formula [1], “D” represents a tetravalent metal element in which Si is essential. The element D may contain germanium (Ge) or the like within a range that does not affect the properties of the obtained phosphor. The proportion of Si with respect to the entire D element is preferably 50 mol% or more, more preferably 70 mol% or more, and particularly preferably 90 mol% or more. If the ratio of Si to the entire D element is too small, impurities are generated, and it tends to be difficult to obtain a phosphor having the target composition.

In the above formula [1], “E” represents a trivalent metal element in which Al is essential. The element E may contain boron (B), gallium (Ga), or the like within a range that does not affect the properties of the obtained phosphor. The proportion of Al to the entire E element is preferably 50 mol% or more, more preferably 70 mol% or more, and particularly preferably 90 mol% or more. If the ratio of Al to the entire E element is too small, impurities are generated, and it tends to be difficult to obtain a phosphor having the target composition.

In the formula [1], “N” represents nitrogen. The N element only needs to contain nitrogen as a main component, and may contain fluorine (F), chlorine (Cl), or the like within a range that does not affect the characteristics of the obtained phosphor.

In the formula [1], “O” represents oxygen. The O element only needs to contain oxygen as a main component, and may contain F, Cl, or the like within a range that does not affect the characteristics of the obtained phosphor.

The phosphor of the first embodiment of the present invention affects the effects of the first embodiment of the present invention in addition to the above-described constituent elements of A, Eu, D, E, N and O. It may contain an element inevitably mixed within a range, for example, an impurity element.

In the formula [1], “x” represents the molar ratio of the activator element (Eu). x is a number satisfying 0.0001 ≦ x ≦ 0.20, preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, and preferably 0.19. In the following, it is more preferably 0.17 or less, further preferably 0.15 or less, particularly preferably 0.12 or less.

If the value of x is too large, concentration quenching tends to occur and the brightness tends to decrease. If it is too small, the absorption efficiency tends to decrease, and the brightness tends to decrease accordingly.

In the above formula [1], “a” represents the sum of molar ratios of the element A (an alkaline earth metal element essential for Sr and Ca) and the activator element (Eu). a is usually a number satisfying 0.7 ≦ a ≦ 1.3, preferably 0.8 or more, more preferably 0.9 or more, particularly preferably 0.95 or more, and preferably 1. It is 2 or less, more preferably 1.1 or less, and particularly preferably 1.05 or less.

The molar ratio of “a” and the moles of “b” and “c” described below are within the scope of the first embodiment of the present invention, that is, the D element (a tetravalent metal element in which Si is essential) and By setting the ratio of element E (trivalent metal element essential for Al) within a specific range, element A (alkaline earth metal element essential for Sr and Ca) is surely solid-dissolved. A phosphor exhibiting the effect can be obtained.

In the above formula [1], “b” represents the molar ratio of the D element (a tetravalent metal element in which Si is essential). b is a number satisfying 2.8 ≦ b ≦ 4.0, preferably 3.0 or more, more preferably 3.2 or more, more preferably 3.4 or more, more preferably 3.5 or more, particularly Preferably, it is 3.55 or more, preferably 3.9 or less, more preferably 3.8 or less, still more preferably 3.7 or less, and particularly preferably 3.65 or less.

In the above formula [1], “c” represents the molar ratio of the E element (a trivalent metal element in which Al is essential). c is a number satisfying 1.0 ≦ c ≦ 3.0, preferably 1.1 or more, more preferably 1.2 or more, still more preferably 1.3 or more, and preferably 2.5 or more. Below, more preferably 2.0 or less, still more preferably 1.75 or less, particularly preferably 1.5 or less.

Further, (b + c) / a is a ratio of the sum of the molar ratio of the D element and the E element to the sum of the molar ratio of the A element and the activator element, and is generally 4.0 ≦ (b + c) / a ≦ 6 It is a number satisfying .0. Further, (b + c) / a is preferably 4.25 or more, more preferably 4.5 or more, still more preferably 4.75 or more, and preferably 5.75 or less, more preferably 5.5. Hereinafter, it is more preferably 5.25 or less.

In the above formula [1], “d” represents the molar ratio of N element (nitrogen). d is a number satisfying 5.0 ≦ d ≦ 7.0, preferably 5.5 or more, more preferably 6.0 or more, further preferably 6.25 or more, and particularly preferably 6.5 or more. Also, it is preferably 6.9 or less, more preferably 6.8 or less, and particularly preferably 6.7 or less.

In the above formula [1], “e” represents the molar ratio of O element (oxygen). e is a number satisfying 0 <e ≦ 2.0, preferably 0.1 or more, more preferably 0.2 or more, still more preferably 0.3 or more, still more preferably 0.4 or more, More preferably 0.45 or more, further preferably 0.5 or more, particularly preferably 0.55 or more, preferably 1.5 or less, more preferably 1.0 or less, more preferably 0.8 or less. More preferably, it is 0.6 or less.

Further, (d + e) / a is the ratio of the sum of the molar ratios of N element (nitrogen) and O element (oxygen) to the sum of the molar ratios of element A and activator element, and usually 6.5 ≦ ( d + e) /a≦7.5. Further, (d + e) / a is preferably 6.7 or more, more preferably 6.9 or more, particularly preferably 6.95 or more, and preferably 7.3 or less, more preferably 7.1 or less. Particularly preferably, it is 7.05 or less.

As described above, in the phosphor according to the first embodiment of the present invention, the molar ratio of a, the molar ratio of d, and the molar ratio of e are within the above ranges, that is, a, b, c, (b + c) / a, By setting the number of d, e, and (d + e) / a within the above range, the A element can be reliably dissolved, and a phosphor exhibiting the above-described effects can be obtained.

When the phosphor of the first embodiment is subjected to elemental analysis, Sr is 13.5 wt% or more and 25.4% or less, Ca is more than 0 and 6.3 wt% or less, Eu is more than 0 and 5.0 or less. Wt% or less, Si 25.0 wt% or more and 37.0 wt% or less, Al 8.1 wt% or more 17.7 wt% or less, N 25.0 wt% or more 33.0 wt% or less, O Is preferably more than 0 and 5.3% by weight or less.

For the second embodiment of the present invention, the description of the first embodiment is incorporated.

The phosphor of the third embodiment of the present invention has the following formula [2]:
(A _1-x , Eu _x ) _a D _b E _c N _d O _e [2]
(In the formula [2], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d, and e represent 0.7 ≦ a ≦ 1.3 and 2.8 ≦ b ≦, respectively. 3.6, 1.0 ≦ c ≦ 3.0, 4.0 ≦ (b + c) /a≦6.0, 5.0 ≦ d ≦ 7.0, 0 <e ≦ 2.0, 6.5 ≦ It includes a crystal phase having a composition represented by (d + e) /a≦7.3.
In said Formula [2], "a" shows the sum of the molar ratio of A element (alkaline earth metal element which makes Sr and Ca essential) and activator element (Eu). a is usually a number satisfying 0.7 ≦ a ≦ 1.3, preferably 0.95 or more, more preferably 0.97 or more, more preferably 0.99 or more, and preferably 1. 05 or less, more preferably 1.03 or less, more preferably 1.1 or less.
The molar ratio of “a” and the moles of “b” and “c” described below are included in the range of the third embodiment of the present invention, that is, D element (a tetravalent metal element in which Si is essential) and By setting the ratio of element E (trivalent metal element essential for Al) within a specific range, element A (alkaline earth metal element essential for Sr and Ca) is surely solid-dissolved. A phosphor exhibiting the effect can be obtained.

In the above formula [2], “b” represents the molar ratio of the D element (a tetravalent metal element in which Si is essential). b is a number satisfying 2.8 ≦ b ≦ 3.6, preferably 2.9 or more, more preferably 3.0 or more, more preferably 3.1 or more, more preferably 3.2 or more. Also, it is preferably 3.55 or less, more preferably 3.50 or less, further preferably 3.45 or less, and particularly preferably 3.4 or less.
In the formula [2], “c” represents the molar ratio of the E element (a trivalent metal element in which Al is essential). c is a number satisfying 1.0 ≦ c ≦ 3.0, preferably 1.4 or more, more preferably 1.45 or more, more preferably 1.5 or more, and further preferably 1.55 or more. Also, it is preferably 2.2 or less, more preferably 2.1 or less, more preferably 2.0 or less, further preferably 1.9 or less, and particularly preferably 1.8 or less.
Further, (b + c) / a is a ratio of the sum of the molar ratio of the D element and the E element to the sum of the molar ratio of the A element and the activator element, and is generally 4.0 ≦ (b + c) / a ≦ 6 It is a number satisfying .0. Further, (b + c) / a is preferably 4.7 or more, more preferably 4.75 or more, more preferably 4.8 or more, still more preferably 4.85 or more, and preferably 5.3. Hereinafter, it is more preferably 5.25 or less, more preferably 5.2 or less, further preferably 5.15 or less, and particularly preferably 5.1 or less.
In said Formula [2], "d" shows the molar ratio of N element (nitrogen). d is a number satisfying 5.0 ≦ d ≦ 7.0, preferably 5.8 or more, more preferably 5.9 or more, more preferably 6.0 or more, still more preferably 6.1 or more, particularly Preferably, it is 6.2 or more, preferably 6.6 or less, more preferably 6.55 or less, more preferably 6.5 or less, further preferably 6.45 or less, and particularly preferably 6.4 or less. is there.

In the above formula [2], “e” represents the molar ratio of O element (oxygen). e is a number satisfying 0 <e ≦ 2.0, preferably 0.4 or more, more preferably 0.45 or more, more preferably 0.5 or more, still more preferably 0.55 or more, and particularly preferably It is 0.6 or more, preferably 1.2 or less, more preferably 1.1 or less, more preferably 1.0 or less, more preferably 0.9 or less, and particularly preferably 0.8 or less. *

Further, (d + e) / a is the ratio of the sum of the molar ratios of N element (nitrogen) and O element (oxygen) to the sum of the molar ratios of element A and activator element, and usually 6.5 ≦ ( d + e) /a≦7.3. Further, (d + e) / a is preferably 6.7 or more, more preferably 6.75 or more, more preferably 6.8 or more, particularly preferably 6.85 or more, and preferably 7.3 or less. More preferably, it is 7.25 or less, More preferably, it is 7.2 or less, Most preferably, it is 7.15 or less.
As described above, in the phosphor of the present invention, the molar ratio of a, the molar ratio of d, and the molar ratio of e are within the above ranges, that is, a, b, c, (b + c) / a, d, e, (d + e ) / A in the above range makes it possible to obtain a phosphor exhibiting the effects described above by reliably dissolving the A element.

Regarding the composition of the phosphor of the third embodiment, the explanation of the first embodiment is incorporated for other items.

<Characteristics of phosphor>
(Peak emission wavelength)
The phosphor of the first embodiment of the present invention is usually 550 nm or more, preferably 570 nm or more, more preferably 575 nm or more, more preferably 580 nm or more, more preferably 582 nm or more, more preferably 590 nm or more, particularly preferably 600 nm. In addition, the emission peak is usually in the wavelength range of 650 nm or less, preferably 630 nm or less, more preferably 610 nm or less. That is, it has a yellow to red light emission color.

The phosphor of the second embodiment is usually 581 nm or more, preferably 582 nm or more, and usually has a light emission peak in a wavelength range of 650 nm or less, preferably 630 nm or less, more preferably 610 nm or less. That is, it has an emission color of orange to red.

The phosphor of the third embodiment is usually 550 nm or more, preferably 570 nm or more, more preferably 575 nm or more, particularly preferably 580 nm or more, and usually 650 nm or less, preferably 600 nm or less, more preferably 595 nm or less, More preferably, it has an emission peak in a wavelength range of 590 nm or less. That is, it has a yellow to orange emission color.

Since the phosphors of the first to third embodiments of the present invention have a wide half-value width of the emission peak, when used in combination with a blue LED, light emission with good color rendering can be obtained with only one type of phosphor. . In addition to the phosphors of the first to third embodiments of the present invention, if a light emitting device is formed by combining a blue to yellow-green phosphor, a red phosphor, or the like, a light emitting device that emits light of higher color rendering can be obtained. Obtainable.

(Half width of emission spectrum)
In the phosphors according to the first to third embodiments of the present invention, the half width of the emission peak is usually 95 nm or more, preferably 97 nm or more, more preferably 100 nm or more, more preferably 103 nm or more, and particularly preferably 105 nm or more. . That is, it shows an emission spectrum with a wide half-value width.

Since the phosphor of the first to third embodiments of the present invention has a wide half-value width of the light emission peak, when used in combination with a blue LED, the first to third embodiments of the present invention are used as the second light emitter. Even when only the above phosphor is used, light emission with good color rendering can be obtained. In particular, when only the phosphor of the third embodiment is used as the second light emitter, a light emitter with particularly good color rendering properties can be obtained, and the effects of the present invention can be remarkably exhibited. In addition to the phosphors of the first to third embodiments of the present invention, if a light emitting device is formed by combining a blue to yellow-green phosphor, a red phosphor, or the like, a light emitting device that emits light of higher color rendering can be obtained. Obtainable.

(CIE chromaticity coordinates)
The x value of the CIE chromaticity coordinate of the phosphor according to the first or second embodiment of the present invention is usually 0.400 or more, preferably 0.425 or more, more preferably 0.450 or more, more preferably 0.00. 50 or more, particularly preferably 0.520 or more, usually 0.66 or less, preferably 0.63 or less, more preferably 0.61 or less, more preferably 0.59 or less, more preferably 0.575 or less, Especially preferably, it is 0.56 or less. The y value of the CIE chromaticity coordinates of the phosphor according to the first or second embodiment of the present invention is usually 0.30 or more, preferably 0.35 or more, more preferably 0.40 or more, and still more preferably. It is 0.425 or more, usually 0.55 or less, preferably 0.525 or less, more preferably 0.510 or less, more preferably 0.50 or less, and particularly preferably 0.46 or less.
On the other hand, the x value of CIE chromaticity coordinates of the phosphor according to the third embodiment of the present invention is usually 0.400 or more, preferably 0.425 or more, more preferably 0.450 or more, and usually 0.8. 575 or less, preferably 0.550 or less, more preferably 0.525 or less, more preferably 0.500 or less, and particularly preferably 0.475 or less. The y value of the CIE chromaticity coordinates of the phosphor of the third embodiment of the present invention is usually 0.425 or more, preferably 0.450 or more, more preferably 0.475 or more, and particularly preferably 0.480. The above is usually 0.550 or less, preferably 0.525 or less, more preferably 0.510 or less.
When the CIE chromaticity coordinates are in the above range, a light emission color with good color rendering can be obtained. In particular, within the range of the CIE chromaticity coordinates of the phosphor of the third embodiment, when combined with a blue LED as the first light emitter, color rendering properties can be achieved by using only the phosphor as the second light emitter. Therefore, it is preferable because a cost advantage and quality can be achieved at the same time.

(Excitation wavelength)
The phosphor according to the first to third embodiments of the present invention has a wavelength range of usually 300 nm or more, preferably 330 nm or more, more preferably 360 nm or more, and usually 500 nm or less, preferably 480 nm or less, more preferably 460 nm or less. Has an excitation peak. That is, it is excited by light in the ultraviolet to blue region.

(Temperature extinction characteristics (emission intensity maintenance rate))
The phosphors according to the first to third embodiments of the present invention also have excellent temperature characteristics. Specifically, the ratio of the emission peak intensity value in the emission spectrum diagram at 100 ° C. to the emission peak intensity value in the emission spectrum diagram at 25 ° C. when light having a peak at a wavelength of 405 nm is usually 50 % Or more, preferably 60% or more, more preferably 70% or more. In addition, since the emission intensity of ordinary phosphors decreases with increasing temperature, it is unlikely that the ratio exceeds 100%, but it may exceed 100% for some reason. However, if it exceeds 150%, the color shift tends to occur due to a temperature change.

(Quantum efficiency)
The external quantum efficiency (η _o ) of the phosphors of the first to third embodiments of the present invention is usually 40% or more, preferably 50 or more, more preferably 60% or more. The higher the external quantum efficiency, the better. The lower the external quantum efficiency, the lower the light emission efficiency.

The internal quantum efficiency, external quantum efficiency, absorption efficiency, and the like can be measured by, for example, the methods described in paragraphs [0026] to [0038] of JP-A-2008-285562.

(Particle size)
The phosphors of the first to third embodiments of the present invention are usually in the form of fine particles. Specifically, the mass median diameter _{D 50} is usually 2μm or more, preferably 5μm or more, and usually 30μm or less, preferably fine particles of the range 20 [mu] m. When the mass median diameter D ₅₀ is too large, for example, tend to dispersibility becomes poor in the resin which is used as a sealing material described later, they tend to be too small and the low luminance.

Mass median diameter D ₅₀ is, for example, obtained by measuring particle size distribution by laser diffraction scattering method, is a value determined from the mass-standard particle size distribution curve. The median diameter D ₅₀ is in this mass-standard particle size distribution curve, the accumulated value refers to the particle size value when the 50%.

The following description is common to all the first to third embodiments of the present invention.

[2. Method for producing phosphor]
In the phosphors according to the first and second embodiments of the present invention, each phosphor raw material preferably has an elemental composition represented by the following formula [3] so as to have a crystal phase composition represented by the formula [1]. Thus, it can be produced by weighing a compound or metal as a raw material to prepare a phosphor raw material mixture and firing the obtained phosphor raw material mixture.

(A _1-x , Eu _x ) _f D _g E _h N _i O _j [3]
(In the formula [3], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. X represents a number satisfying 0.0001 ≦ x ≦ 0.20, and f, g, h, i and j represent 0.7 ≦ f ≦ 1.3 and 2.8 ≦ g ≦, respectively. 4.0, 1.0 ≦ h ≦ 3.0, 4.0 ≦ (g + h) /f≦6.0, 5.0 ≦ i ≦ 7.0, 0 <j ≦ 2.0, 6.5 ≦ (The number satisfying (i + j) /f≦7.5 is indicated.)

In the phosphor according to the third embodiment of the present invention, each phosphor raw material preferably has the composition of the crystal phase represented by the formula [2], preferably the elemental composition is represented by the following formula [4]. In addition, the phosphor raw material mixture can be prepared by weighing the compound or metal used as the raw material, and the obtained phosphor raw material mixture can be fired.

(A _1-x , Eu _x ) _f D _g E _h N _i O _j [4]
(In the formula [4], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. X represents a number satisfying 0.0001 ≦ x ≦ 0.20, and f, g, h, i and j represent 0.7 ≦ f ≦ 1.3 and 2.8 ≦ g ≦, respectively. 3.6, 1.0 ≦ h ≦ 3.0, 4.0 ≦ (g + h) /f≦6.0, 5.0 ≦ i ≦ 7.0, 0 <j ≦ 2.0, 6.5 ≦ (The number satisfying (i + j) /f≦7.3 is shown.)

Note that f, g, h, i, and j correspond to a, b, c, d, and e in the item of the composition of the phosphor of this embodiment, respectively, and explanations of preferred ranges thereof are incorporated.

(Phosphor raw material)
As the phosphor material, a metal compound, a metal, or the like is used. For example, when producing a phosphor having the composition of the crystal phase represented by the above formula [1] or [2], a raw material of A element (hereinafter referred to as “A source” as appropriate), a raw material of D element (hereinafter referred to as “D” as appropriate). Source), E element source (hereinafter referred to as “E source” as appropriate), N element source (hereinafter referred to as “N source” as appropriate), O element source (hereinafter referred to as “O source” as appropriate), Eu element A necessary combination is mixed from raw materials (hereinafter referred to as “Eu source” as appropriate) (mixing step), the resulting mixture is fired (firing step), and the obtained fired product is crushed and pulverized as necessary. Or by washing (post-treatment process).

Among them, the raw material used as the alkaline earth metal source is preferably an alkaline earth metal oxide or an alkaline earth metal carbonate, particularly preferably an alkaline earth metal carbonate. This is because the raw material used as the alkaline earth metal source can be handled in the air, which eliminates the need for atmosphere control during mixing and is advantageous in terms of manufacturing costs.

As the phosphor material used, known materials can be used. For example, as the A source, an Sr source such as Sr ₃ N ₂ , SrO, SrCO ₃ , or a Ca source such as Ca ₃ N ₂ , CaO, CaCO _3, etc. Si source such as SiC, Si ₃ N ₄ , and SiO ₂ as D source, Al source such as AlN, Al ₂ O ₃ , and Al ₄ C ₃ as E source, and Eu metal, oxide, and carbonate as Eu source Eu compounds selected from chlorides, fluorides, nitrides or oxynitrides can be used.

The O source (oxygen) and N source (nitrogen) in the formula [3] or [4] are A source (Sr and Ca source), D source (Si source), E source (Al source), Eu source. May be supplied from a firing atmosphere. Each raw material may contain inevitable impurities.

(Mixing process)
The phosphor raw materials are weighed so as to obtain the target composition, and sufficiently mixed using a ball mill or the like to obtain a phosphor raw material mixture (mixing step).
Although it does not specifically limit as said mixing method, Specifically, the method of following (A) and (B) is mentioned.

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

(B) After adding a solvent or dispersion medium such as water to the above-mentioned phosphor raw material and mixing with, for example, a pulverizer, a mortar and a pestle, or an evaporating dish and a stirring rod, A wet mixing method in which drying is performed by spray drying, heat drying, or natural drying.

The mixing of the phosphor raw material may be either the wet mixing method or the dry mixing method, but in order to avoid contamination of the phosphor raw material with moisture, a dry mixing method or a wet mixing method using a water-insoluble solvent is more preferable. .

(Baking process)
Subsequently, the phosphor material mixture obtained in the mixing step is fired (firing step). The above-mentioned phosphor raw material mixture is dried as necessary and then filled in a container such as a crucible and fired using a firing furnace, a pressure furnace or the like.

When the phosphors according to the first to third embodiments of the present invention are manufactured by the study of the present inventors, in the firing step, the pressure in the furnace is 0.2 MPa or more and 100 MPa or less as described above. It has been found that firing the phosphor raw material mixture is more preferable. Preferred conditions in the firing step are described below.

Examples of the material of the firing container (such as a crucible) used in the firing step include boron nitride and carbon.

Calcination temperature varies depending on other conditions such as pressure, but can be usually performed in a temperature range of 1300 ° C. or higher and 2100 ° C. or lower. The highest temperature reached in the firing step is usually 1200 ° C. or higher, preferably 1400 ° C. or higher, more preferably 1600 ° C. or higher, particularly preferably 1800 ° C. or higher, and usually 2100 ° C. or lower, preferably 2000 ° C. or lower. Preferably it is 1900 degrees C or less. If the firing temperature is too high, nitrogen will fly, generating defects in the host crystal and coloring, and impurities tend to be generated. If it is too low, the progress of the solid phase reaction tends to be slow.

The heating rate in the firing step is usually 2 ° C./min or more, preferably 5 ° C./min or more, more preferably 10 ° C./min or more, and usually 30 ° C./min or less, preferably 25 ° C./min or less. It is. If the rate of temperature rise is below this range, the firing time may be long. In addition, if the rate of temperature rise exceeds this range, the firing device, container, etc. may be damaged.

The firing atmosphere in the firing step is arbitrary as long as the phosphors according to the first to third embodiments of the present invention are obtained, but a nitrogen-containing atmosphere is preferable. Specific examples include a nitrogen atmosphere and a hydrogen-containing nitrogen atmosphere, and a nitrogen atmosphere is particularly preferable. The oxygen content in the firing atmosphere is usually 10 ppm or less, preferably 5 ppm or less.

The firing time varies depending on the temperature and pressure during firing, but is usually 10 minutes or longer, preferably 30 minutes or longer, and usually 24 hours or shorter, preferably 12 hours or shorter.

Although the pressure in the firing step varies depending on the firing temperature and the like, the pressure in the furnace can be set to atmospheric pressure (0.1013 MPa) or a pressurized state. The pressure in the firing step is usually 0.1013 MPa or more, preferably 0.2 MPa or more, more preferably 0.4 MPa or more, and usually 100 MPa or less, preferably 50 MPa or less, more preferably 20 MPa or less, particularly preferably 10 MPa. It is as follows. If the pressure is too high, by-products tend to increase, and if the pressure is too low, the obtained phosphor may be decomposed or colored, so adjustment of the pressure is important.

In addition, you may repeat a baking process in multiple times as needed. In that case, the firing conditions may be the same or different between the first firing and the second firing. It is preferable to perform the second baking at a relatively high temperature after the first baking as a preliminary baking at a relatively low temperature in order to reduce the impurity phase and increase the luminous efficiency.

(Post-processing process)
The obtained fired product is granular or massive. This is pulverized, pulverized and / or classified into a powder of a predetermined size. _Here, it is preferable to process as _{D 50} is less than about 30 [mu] m.

Specific examples of the treatment include a method of subjecting the synthesized product to sieve classification with an opening of about 45 μm, and passing the powder that has passed through the sieve to the next step, or the synthesized product to a general method such as a ball mill, a vibration mill, or a jet mill. The method of grind | pulverizing to a predetermined particle size using a grinder is mentioned. In the latter method, excessive pulverization not only generates fine particles that easily scatter light, but also generates crystal defects on the particle surface, which may cause a decrease in luminous efficiency.

Further, if necessary, a step of cleaning the phosphor (baked product) may be provided. After the cleaning step, the phosphor is dried until it has no adhering moisture and is used. Further, if necessary, dispersion / classification treatment may be performed to loosen the aggregation.

[3. Use of phosphor]
The phosphor according to the first to third embodiments of the present invention can be used for any application using the phosphor. The phosphors of the first to third embodiments of the present invention can be used alone, but two or more kinds of phosphors can be used together, or the phosphors of the first to third embodiments of the present invention can be used together. It can also be used as a phosphor mixture of any combination, such as in combination with other phosphors.

The phosphors of the first to third embodiments of the present invention can be used as a phosphor-containing composition by mixing with a known liquid medium (for example, a silicone compound).
In addition, the phosphor obtained by the first to third embodiments of the present invention can be used in various light emitting devices by combining with a light source that emits ultraviolet light, taking advantage of the fact that it can be excited by ultraviolet light. It can be used suitably.

The emission color of the light-emitting device is not limited to purple or white, but by appropriately selecting the combination and content of phosphors, light emission that emits light in any color, such as light bulb color (warm white) or pastel color The device can be manufactured. The light-emitting device thus obtained can be used as a light-emitting portion (particularly a liquid crystal backlight) or an illumination device of an image display device.

[4. Phosphor-containing composition]
The phosphors of the first to third embodiments of the present invention can be used by mixing with a liquid medium. In particular, when the phosphor of the first to third embodiments of the present invention is used for a light emitting device or the like, it is preferably used in a form dispersed in a liquid medium. The phosphor of the first to third embodiments of the present invention dispersed in a liquid medium is appropriately referred to as “the phosphor-containing composition of the present invention”, and the fourth embodiment of the present invention is A phosphor-containing composition obtained by dispersing at least one phosphor described above in a liquid medium.

(Phosphor)
There is no restriction | limiting in the kind of fluorescent substance of the 1st thru | or 3rd embodiment of this invention contained in the said fluorescent substance containing composition, It can select arbitrarily from what satisfy | fills the condition. Moreover, the fluorescent substance of the 1st thru | or 3rd embodiment of this invention contained in a fluorescent substance containing composition may be only 1 type, and may use 2 or more types together by arbitrary combinations and ratios. . Furthermore, the phosphor-containing composition may contain a phosphor other than the phosphors of the first to third embodiments of the present invention as long as the effects of the present embodiment are not significantly impaired.

(Liquid medium)
The kind of liquid medium used for the phosphor-containing composition 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, as the curable material, any of inorganic materials, organic materials, and mixtures thereof can be used.

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 methyl poly (meth) acrylate; styrene resins such as polystyrene and styrene-acrylonitrile copolymers; polycarbonate resins; polyester resins; phenoxy resins; butyral resins; Cellulose resins such as cellulose acetate and cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins and the like.

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, a silicone-based material such as a condensation type, an addition type, an improved sol-gel type, and a photocurable type can be used.

As the condensation type silicone material, for example, semiconductor light-emitting device members described in JP-A No. 2007-129973 to No. 112975, JP-A No. 2007-19459, JP-A No. 2008-34833 and the like can be used. Condensation-type silicone materials have excellent adhesion to 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 No. 2004-186168, JP-A No. 2004-221308, JP-A No. 2005-327777, JP-A No. 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.

Further, as an improved sol-gel type silicone material which 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 are 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-based material, for example, silicone materials described in JP2007-131812A, JP2007-214543A, 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 plurality of silicone materials may be mixed and used as long as they do not inhibit curing by mixing.

(Content of liquid medium and phosphor)
The content of the liquid medium is arbitrary as long as the effect of the present embodiment is not significantly impaired, but is usually 25% by mass or more, preferably 40% by mass or more with respect to the entire phosphor-containing composition of the present embodiment. Moreover, it is 99 mass% or less normally, Preferably it is 95 mass% or less, More preferably, it is 80 mass% 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 has a role as a binder in the phosphor-containing composition of the present embodiment. 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 mass or less, preferably 10% by mass or less, based on the total amount of the liquid medium as the binder.

The phosphor content in the phosphor-containing composition is arbitrary as long as the effect of the present embodiment is not significantly impaired, but is usually 1% by mass or more, preferably with respect to the entire phosphor-containing composition of the present embodiment. Is 5% by mass or more, more preferably 20% by mass or more, and usually 75% by mass or less, preferably 60% by mass or less. The proportion of the phosphor of the first to third embodiments of the present invention in the phosphor in the phosphor-containing composition is also arbitrary, but is usually 30% by mass or more, preferably 50% by mass or more. Usually, it is 100 mass% 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.

(Other ingredients)
In addition to the phosphor and the liquid medium, the phosphor-containing composition has other components such as a metal oxide for adjusting the refractive index, a diffusing agent, a filler, and a viscosity, as long as the effects of the present embodiment are not significantly impaired. You may contain additives, such as a regulator and a ultraviolet absorber. 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]
According to a fifth embodiment of the present invention, there is provided a first light emitter (excitation light source) and a second light emitter that can emit visible light by converting light from the first light emitter into visible light. A light-emitting device having the above-described [1. It contains a first phosphor containing one or more of the phosphors of the first to third embodiments described in the section [Phosphor].

The light emitting device of this embodiment includes a first phosphor as the second light emitter. As a result, it is possible to provide a light emitting device excellent in color rendering and color reproducibility even when only the phosphors of the first to third embodiments are used in the light emitting device. When the ratio of the first phosphor in the second phosphor is 95% by mass or more, preferably 98% by mass or more, and more preferably 99.9% by mass or more, different types of phosphors By mixing the phosphors, it is possible to avoid the problem of self-absorption that other phosphors absorb the light emission of the phosphors, so that a light-emitting device with high luminous efficiency can be provided.

Favorable specific examples of the phosphors of the first to third embodiments used in the light emitting device of the present embodiment include [1. Examples include phosphors according to the embodiments described in the “Phosphor” column, and phosphors used in each Example in the “Example” column described below. In addition, the phosphors of the first to third embodiments may be used alone or in combination of two or more in any combination and ratio.

The light emitting device of this embodiment has a first light emitter (excitation light source) and uses at least the phosphors of the first to third embodiments as the second light emitter. The configuration is not limited, and a known device configuration can be arbitrarily employed. A specific example of the device configuration will be described later.

Among the light emitting devices of the present embodiment, in particular, as a white light emitting device, specifically, an excitation light source as described later is used as the first light emitter, and in addition to the phosphors of the first to third embodiments, the light source will be described later. Such a phosphor that emits blue fluorescence (hereinafter referred to as “blue phosphor” as appropriate), a phosphor that emits green fluorescence (hereinafter referred to as “green phosphor” as appropriate), and a phosphor that emits red fluorescence (hereinafter referred to as “green phosphor”). By appropriately combining known phosphors such as “red phosphor” and yellow phosphor (hereinafter referred to as “yellow phosphor” as appropriate) and using a known apparatus configuration can get.

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

<Configuration of light emitting device>
(First luminous body)
The first light emitter in the light emitting device of this embodiment emits light that excites a second light emitter described 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, a light emitter having an emission wavelength from the ultraviolet region to the blue region is used.

The specific value of the emission peak wavelength of the first illuminant is usually 300 nm or more, preferably 330 nm or more, more preferably 360 nm or more, and usually 500 nm or less, preferably 480 nm or less, more preferably 460 nm or less. It is desirable to use a light emitter having a wavelength.

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 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.
Among the first light emitters described above, a blue LED is preferable as the first light emitter used in the light emitting device of the present invention. In this case, the specific value of the emission peak wavelength of the first illuminant is usually 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 500 nm or less, preferably 480 nm or less, more preferably 460 nm or less. It is desirable to use an illuminant having an emission peak wavelength in the above range.
In the light emitting device of the present invention, a light emitting device with high color rendering can be obtained by including at least one blue LED and the phosphors of the first to third embodiments. In particular, the phosphor of the third embodiment. The use of is particularly preferred.

In the light emitting device of this embodiment, a blue LED and one or more phosphors of the first to third embodiments can be used to obtain a light emitting device with high color rendering, but as another embodiment, A light emitting device in which a near-ultraviolet LED, the phosphor of the first to third embodiments (first phosphor), and the blue phosphor (second phosphor) are combined can also be provided. The specific value of the emission peak wavelength of the first illuminant at this time is usually 300 nm or more, preferably 330 nm or more, more preferably 360 nm or more, and usually 420 nm or less, preferably 415 nm or less, more preferably 410 nm or less. It is desirable to use an illuminant having an emission peak wavelength in the above range. The specific value of the emission peak wavelength of the second phosphor (blue phosphor) at this time is usually 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 500 nm or less, preferably 480 nm or less, More preferably, it is desirable to use a phosphor having an emission peak wavelength in a range of 460 nm or less.

(Second light emitter)
The second light emitter in the light emitting device of the present embodiment is a light emitter that emits visible light when irradiated with the light from the first light emitter described above, and the first to third embodiments are used as the first phosphor. In addition to containing one or more of the above phosphors, the second phosphor (blue phosphor, green phosphor, yellow phosphor, orange phosphor, red phosphor, etc.), which will be described later, is appropriately included depending on the application. can do. Further, for example, the second light emitter is configured by dispersing the first and second phosphors in a sealing material.

There is no particular limitation on the composition of the phosphor other than the phosphors of the first to third embodiments (that is, the second phosphor) used in the second luminous body, but it becomes a base crystal. Y ₂ O ₃ , YVO ₄ , Zn ₂ SiO ₄ , metal oxides typified by Y ₃ A ₁₅ O ₁₂ , Sr ₂ SiO ₄ , metal nitrides typified by Sr ₂ Si ₅ N ₈ , Ca ₅ Ce in phosphates typified by (PO ₄ ) ₃ Cl and the like, sulfides typified by ZnS, SrS, CaS and the like, oxysulfides typified by Y ₂ O ₂ S and La ₂ O ₂ S and the like , Ions of rare earth metals such as Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and ions of metals such as Ag, Cu, Au, Al, Mn, Sb A combination of the coactivator elements is included.
Specific examples of preferred crystal matrixes are shown in Table 1.

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 embodiment are not limited to these. In the following examples, as described above, phosphors that differ only in part of the structure are omitted as appropriate.

(First phosphor)
The second light emitter in the light emitting device of this embodiment contains at least the first phosphor including the phosphors of the first to third embodiments described above. Any one of the phosphors of the first to third embodiments may be used alone, or two or more thereof may be used in any combination and ratio, so that a desired emission color is obtained. What is necessary is just to adjust suitably the composition of the fluorescent substance of the 1st thru | or 3rd embodiment.

(Second phosphor)
The second light emitter in the light emitting device of the present embodiment may contain a phosphor (that is, the 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 mass median diameter D ₅₀ that is used for the light emitting device of the present embodiment is generally 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 mass median diameter D ₅₀ is too small, and the luminance decreases tends to phosphor particles tend to aggregate. On the other hand, when the mass median diameter is too large, there is a tendency for coating unevenness and blockage of a dispenser to occur.

(Blue phosphor)
When a blue phosphor is used as the second phosphor, any blue phosphor can be used as long as the effect of the present embodiment is 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 this embodiment, and the phosphor of this embodiment is efficiently excited by the blue light from the blue phosphor. Because you can. Table 2 shows phosphors that can be used as such blue phosphors.

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

(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 embodiment 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. Table 3 shows phosphors that can be used as such green phosphors.

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 preferred.

When the obtained light-emitting device is used for a lighting device, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, CaSc ₂ O ₄ : CeCa 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.

(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 embodiment 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. Table 4 shows phosphors that can be used as such yellow phosphors.

More in even, as the yellow _{_{_{_{phosphor, Y 3 Al 5 O 12:}}}} Ce, (Y, Gd) 3 A l5 O 12: Ce, (Sr, Ca, Ba, Mg) 2 SiO 4: Eu, (Ca, Sr) Si ₂ N ₂ O ₂ : Eu is preferred.

(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 effect of the present embodiment is 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. Table 5 shows phosphors that can be used as such orange to red phosphors.

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) ) Β-diketone Eu complex such as 3,1,10-phenanthroline complex, 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.

<Embodiment of Light Emitting Device>
Hereinafter, the light-emitting device of this embodiment will be described in more detail with specific embodiments, but 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 any modification.

The typical perspective view which shows the positional relationship of the 1st light-emitting body used as an excitation light source, and the 2nd light-emitting body comprised as a fluorescent substance containing part which has fluorescent substance in an example of the light-emitting device of this embodiment is a figure. It is shown in 1. 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, the excitation light source (LD) 2 and the phosphor-containing portion 1 (second light emitter) are separately manufactured, and their surfaces are brought into contact with each other by an adhesive or other means. Alternatively, the phosphor-containing portion 1 (second light emitter) may be formed (molded) on the light emitting surface of the excitation light source (LD) 2. As a result, the excitation light source (LD) 2 and the phosphor-containing part 1 (second light emitter) can be brought into contact with each other.

When such an apparatus configuration is employed, the light loss is such that light from the excitation light source (first light emitter) is reflected by the film surface of the phosphor-containing portion (second light emitter) and oozes out. Therefore, the light emission efficiency of the entire device can be improved.
FIG. 2A is a typical example of a light emitting device of a form generally referred to as a shell type, and has a light emission having an excitation light source (first light emitter) and a phosphor-containing portion (second light emitter). It is typical sectional drawing which shows one Example of an apparatus. In the light emitting device 4, reference numeral 5 is a mount lead, reference numeral 6 is an inner lead, reference numeral 7 is an excitation light source (first light emitter), reference numeral 8 is a phosphor-containing portion, reference numeral 9 is a conductive wire, and reference numeral 10 is a mold. Each member is indicated.

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.

<Characteristics of light emitting device>
In the light emitting device of this embodiment, the Ra of the emission color is usually 58 or more, preferably 60 or more, more preferably 62 or more, and particularly preferably 64 or more. As the value of Ra is larger, a light emitting device having better color rendering properties can be obtained.
In the light emitting device of this embodiment, the special color rendering index R9 of the emitted color is usually minus 75 or more, preferably minus 70 or more, more preferably minus 65 or more, particularly preferably minus 60 or more. When the special color rendering index R9 is in the above range, a light emitting device having good color rendering properties can be obtained.

In the light emitting device of this embodiment, the correlated color temperature of the emitted color is usually 2600 K or higher, preferably 2700 K or higher, particularly preferably 2800 K or higher, and usually 4500 K or lower, preferably 4300 K or lower, more preferably 4000 K or lower, Preferably it is 3700K or less, Especially preferably, it is 3400K or less.
When the correlated color temperature is in the above-described range, a light emitting device that exhibits a warm emission color from a preferable white color to a light bulb color (a range in which the correlated color temperature is 2600K to 4500K) can be obtained.

<Applications of light emitting device>
The application of the light-emitting device of this embodiment is not particularly limited, and can be used in various fields where a normal light-emitting device is used. However, since the color rendering property is high and the color reproduction range is wide, illumination is particularly important. It is particularly preferably used as a light source for a device or an image display device.

[6. Lighting device and image display device]
A sixth embodiment of the present invention is an illumination device or an image display device including the above-described light emitting device.

<Lighting device>
When the light emitting device according to the fifth embodiment of the present invention is applied to a lighting device, the light emitting device as described above may be appropriately incorporated in 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 cited.
FIG. 3 is a cross-sectional view schematically showing one embodiment of the illumination device of the present embodiment. As shown in FIG. 3, the surface-emitting illumination device has a large number of light-emitting devices 13 (on the light-emitting device 4 described above) on the bottom surface of a rectangular holding case 12 whose inner surface is light-opaque such as a white smooth surface. Is provided with a power source and a circuit (not shown) for driving the light-emitting device 13 on the outside, and a milky white acrylic plate or the like is provided at a position corresponding to the lid portion of the holding case 12. The diffusion plate 14 is fixed for uniform light emission.

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

<Image display device>
When the light emitting device of the fifth embodiment 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.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In addition, the values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the value of the upper limit or the lower limit. It may be a range defined by a combination of values of the following examples or values of the examples.

[Measurement and evaluation method of phosphor characteristics]
In each Example and Comparative Example, various characteristics measurement / evaluation of the phosphor particles were performed by the following method unless otherwise specified.

<Emission spectrum>
Measurement was performed using a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a 150 W xenon lamp as an excitation light source and a multichannel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus.

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 455 nm was irradiated to the phosphor through the optical fiber. The light generated from the phosphor by the irradiation of the excitation light is dispersed by a diffraction grating spectroscope having a focal length of 25 cm, the emission intensity of each wavelength is measured by a spectrum measuring device in a wavelength range of 300 nm to 800 nm, and a personal computer is used. 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”) was read from the obtained emission spectrum. The relative peak intensity was expressed as a relative value with the peak intensity of Comparative Example 1 as the reference value 100. The relative emission luminance is a range obtained by excluding the excitation wavelength region from the emission spectrum in the visible region obtained by the above-described method, and the stimulus of Comparative Example 3 from the stimulus value Y in the XYZ color system calculated according to JIS Z8724. The value Y was calculated as a relative value (hereinafter, sometimes simply referred to as “luminance”) with 100%.

<Chromaticity coordinates>
The chromaticity coordinates of the x, y color system (CIE 1931 color system) are obtained from the data in the wavelength region of 360 nm to 800 nm of the emission spectrum obtained by the above method, according to JIS Z8724. The chromaticity coordinates x and y in the prescribed XYZ color system were calculated.

<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>
Precision measurement was performed with a powder X-ray diffractometer X′Pert (manufactured by PANalytical). The measurement conditions are as follows. For the measurement data, automatic background processing was performed 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
Divergence slit = 1/4 °, X-ray mirror Detector = Semiconductor array detector X'Celerator used Ni filter used Scanning range 2θ = 10 ° to 65 °
Reading width = 0.05 °
Counting time = 33 seconds

<Lattice constant refinement>
From the powder X-ray diffraction measurement data of each example and comparative example, the lattice constant has a skeletal structure composed of Si, Al, N, and O, and has a crystal structure in which Sr sites exist in the voids. The same crystal structure as SrAlSi ₄ N ₇ which is a kind of phosphor, that is, a peak due to the crystal structure in which the space group is classified as Pna2 ₁ , is selected and data processing software X'Pert Plus (manufactured by PANalytical) is used. Obtained by refining.

<Composition analysis>
For Sr, Ca, Si, Al, and Eu, the obtained phosphor was subjected to alkali melting treatment, acid dissolution, and quantitative analysis by ICP-AES (ULTIMA 2C manufactured by Horiba Seisakusho).
For O and N, quantitative analysis was performed using an oxygen / nitrogen / hydrogen analyzer (TCH600, manufactured by LECO) by a true pulse furnace heating extraction-IR detection method and a TCD detection method in an inert gas atmosphere.

[Examples 1 to 13, 17 and Comparative Examples 1 to 3]
As phosphor raw materials, Sr ₃ N ₂ (manufactured by Shellac), Ca ₃ N ₂ (manufactured by Shellac), Si ₃ N ₄ (manufactured by Ube Industries), Al ₂ O ₃ (manufactured by Sumitomo Chemical), AlN (Tokuyama) The phosphor was prepared as follows using Eu ₂ O ₃ (manufactured by Shin-Etsu Chemical Co., Ltd.).

(Weighing, grinding and mixing)
The raw materials were weighed with an electronic balance so as to have the charged compositions of Examples 1 to 13 and 17 and Comparative Examples 1 to 3 shown in Table 6, placed in an alumina mortar, and ground and mixed until uniform. These operations were performed in a glove box filled with N ₂ gas.

(Baking)
About 1 g of the obtained raw material mixed powder was weighed and filled into a boron nitride crucible (BN crucible) as it was. This BN crucible was placed in a resistance heating type vacuum pressure atmosphere heat treatment furnace (manufactured by Fuji Denpa Kogyo Co., Ltd.). Subsequently, the pressure was reduced to 5 × 10 ⁻³ Pa or less, and then vacuum heating was performed from room temperature to 800 ° C. at a temperature rising 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 1600 ° C. at a rate of temperature increase of 20 ° C./min. When the temperature reached 1600 ° C., the temperature was maintained for 2 hours, followed by heating to 1850 ° C. at 20 ° C./min, and the temperature was maintained for 6 hours. After firing, the mixture was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, and then allowed to cool. Thereafter, the product was crushed to obtain phosphors of Examples 1 to 13, 17 and Comparative Examples 1 to 3.

[Examples 14 to 16]
Phosphors were prepared in the same manner as in Examples 1 to 13, 17 and Comparative Examples 1 to 3, except that the following preliminary firing was performed before firing.

(Preliminary firing)
About 1 g of the obtained raw material mixed powder was weighed and filled into a boron nitride crucible (BN crucible) as it was. This BN crucible was placed in a resistance heating type vacuum pressure atmosphere heat treatment furnace (manufactured by Fuji Denpa Kogyo Co., Ltd.). Subsequently, the pressure was reduced to 5 × 10 ⁻³ Pa or less, and then vacuum heating was performed from room temperature to 800 ° C. at a temperature rising 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 1500 ° C. at a temperature rising rate of 20 ° C./min. When it reached 1500 ° C., it was maintained for 8 hours. After firing, the mixture was cooled to 1200 ° C. at a temperature lowering rate of 20 ° C./min, and then allowed to cool. Thereafter, the product was crushed to obtain pre-fired products of Examples 14 to 16.

(Baking)
About 1 g of the obtained preliminary fired product was weighed and filled in a boron nitride crucible (BN crucible) as it was, and fired in the same manner as in Examples 1 to 13, 17 and Comparative Examples 1 to 3.

[Examples 18 to 28]
Examples 1 to 13 and 17 and Comparative Example except that Ba ₃ N ₂ (manufactured by Taiheiyo Cement Co., Ltd.) was used as the phosphor raw material, and the respective charge compositions of Examples 18 to 28 shown in Table 7 were used. Phosphors were obtained in the same manner as in Examples 1 to 3.

The various characteristics of the obtained phosphor were evaluated by the methods described above. The results are shown in Tables 8 to 10, Table 12 below, and FIGS. Comparative Examples 1 to 3 are phosphors in which Ca is not substituted at all, Examples 1 to 5 are phosphors in which Ca is substituted at a ratio of 10 mol% with respect to Sr, and Examples 6 to 12 and 17 are based on Sr. Phosphors in which Ca was substituted at a ratio of 20 mol%, Examples 13 to 15 and 18 to 21 were phosphors in which Ca was substituted at a ratio of 30 mol% to Sr, and Examples 16 and 22 to 23 were Sr Phosphors in which Ca was substituted at a ratio of 40 mol% with respect to Example 24, Examples 24 to 28 were phosphors in which Ca was substituted at a ratio of 30 mol% and Ba at a ratio shown in Table 7.

Table 8 shows the results of refinement of the lattice constant based on the powder X-ray diffraction patterns of the phosphors of Examples 1 to 17 and Comparative Examples 1 to 3, and Patent Document 3 (Japanese Patent Publication No. 2010-518194). Are the lattice constants and unit lattice volume (V) values of SrAlSi ₄ N ₇ described in (Comparative Example 4). As the Sr site in the crystal structure was replaced with Ca, the unit cell volume decreased. Therefore, it was confirmed that the phosphor obtained in the present invention was able to reliably replace Ca at the Sr site and arbitrarily adjust the unit cell volume.

4 is a powder X-ray pattern of the phosphors of Examples 2, 3, 6, 10 and Comparative Example 1. FIG. The obtained powder X-ray diffraction pattern has a skeleton structure composed of Si, Al, N, and O, and SrAlSi ₄ N, which is a kind of phosphor having a crystal structure in which Sr sites exist in the voids. ₇ shows a crystal phase having the same crystal structure as that of FIG. ₇ , that is, a space group of a crystal structure in which the space group is classified as Pna2 ₁ , and the peak positions are slightly different. Moreover, it was confirmed that the difference in peak intensity ratio seen in FIG. 4 is the influence of selective orientation in the measurement.

FIG. 5 shows emission spectra of the phosphors obtained in Examples 2, 3, 6 to 9, 13 and Comparative Example 1. It was confirmed that the peak intensities of the phosphors of all the examples were increased from the peak intensity of Comparative Example 1. That is, the emission intensity was increased by adjusting the unit cell volume.

FIG. 6 is an excitation spectrum of the phosphor obtained in Example 2. It has been found that the phosphor of this example exhibits high-intensity orange light emission over a wide range of wavelengths from 300 nm to 550 nm, particularly from 400 nm to 500 nm.

7 is a powder X-ray pattern of the phosphors of Examples 4 and 11 and Comparative Example 2, and FIG. 8 is an emission spectrum of those phosphors. In the phosphors of Examples 4 and 11, the ratio of Si and Al in the crystal structure is the same as that of the phosphor of Comparative Example 2, and only the amount of substitution of Ca is changed. In Comparative Example 2, a peak due to the impurity phase was confirmed, but in Example 4, the intensity decreased, and in Example 11, it was not confirmed. This suggests that by replacing the Sr site with Ca, the unit cell volume was adjusted and a phosphor having a more stable structure could be generated. Accordingly, the generation of the impurity phase is suppressed, and the target crystal phase is easily generated selectively, so that an increase in emission intensity is achieved.

FIG. 9 shows emission spectra of the phosphors of Examples 5 and 12 and Comparative Example 3. In the phosphors of Examples 5 and 12, the ratio of Si and Al in the crystal structure is the same as that of the phosphor of Comparative Example 3, and only the amount of substitution of Ca is changed. As compared with Comparative Example 3, the emission intensity increased in accordance with Example 5 and Example 12. This is because, as in the phosphors of Examples 4 and 11, and Comparative Example 2, the Sr site was replaced with Ca, whereby the unit cell volume was adjusted and a phosphor having a more stable structure could be generated. It is suggested.

FIG. 10 is a powder X-ray pattern of the phosphors of Examples 18 to 23. The obtained powder X-ray diffraction pattern has a skeleton structure composed of Si, Al, N, and O, and SrAlSi ₄ N, which is a kind of phosphor having a crystal structure in which Sr sites exist in the voids. ₇ shows a crystal phase having the same crystal structure as that of FIG. ₇ , that is, a space group of a crystal structure in which the space group is classified as Pna2 ₁ , and the peak positions are slightly different. Moreover, it was confirmed that the difference in peak intensity ratio seen in FIG. 10 is the influence of selective orientation in the measurement.

FIG. 11 shows emission spectra of the phosphors of Examples 18 to 23. It can be seen that the emission peak wavelength can be controlled by adjusting the ratio of Si, Al, N, and O constituting the skeleton structure and the Ca substitution amount of the Sr site.

FIG. 12 is a powder X-ray pattern of the phosphors of Examples 18 and 24-28. The obtained powder X-ray diffraction pattern has a skeleton structure composed of Si, Al, N, and O, and SrAlSi ₄ N, which is a kind of phosphor having a crystal structure in which Sr sites exist in the voids. ₇ shows a crystal phase having the same crystal structure as that of FIG. ₇ , that is, a space group of a crystal structure in which the space group is classified as Pna2 ₁ , and the peak positions are slightly different. Moreover, it was confirmed that the difference in peak intensity ratio seen in FIG. 12 is the influence of the selective orientation in the measurement. In other words, it was confirmed that Ba could be solid solution-substituted at the ratio shown in Table 7 for the Sr sites in the crystal structure.

FIG. 13 shows the emission spectra of the phosphors of Examples 18 and 24-28. When the ratio of Si, Al, N, and O constituting the skeleton structure and the Ca substitution amount of the Sr site are made constant, and the Sr site is substituted with Ba, the full width at half maximum increases as the substitution amount increases. Was confirmed. That is, it was confirmed that the half-value width can be controlled by replacing the Sr site in the crystal structure of the phosphor of the present invention with Ba.

Table 9 shows the measurement results of the emission peak wavelength, CIE chromaticity coordinates, emission peak half width, and relative emission peak intensity of the phosphors of Examples 1 to 4, 6 to 11, and 13 and Comparative Examples 1 and 2. . In all the phosphors of the examples, the peak intensity is increased from the peak intensity of Comparative Examples 1 and 2 while maintaining a wide half-value width, and the emission intensity is high in a wide range from yellow to red. It was confirmed that an excellent phosphor could be produced. This is considered to be because by replacing the Sr site with Ca together with the composition of the skeletal structure, the unit cell volume was adjusted and optimum stable structures could be constructed in various emission colors.

Table 10 shows the measurement results of the emission peak wavelength, CIE chromaticity coordinates, emission peak half-value width, and relative emission luminance of the phosphors of Examples 5, 12, 14 to 17 and Comparative Example 3. In all the phosphors of the examples, the relative light emission luminance is higher than the relative light emission luminance of Comparative Example 3 while maintaining a wide half width. By replacing the Sr site with Ca together with the composition of the skeletal structure, the unit cell volume can be adjusted, and the emission color can be adjusted without reducing the light emission efficiency. This is considered to be because a phosphor with high luminance was obtained in a wide range.

[Examples 29 and 30]
A phosphor was prepared in the same manner as in Example 9 in Example 29 and in the same manner as in Example 14 in Example 30. The obtained phosphor was subjected to composition analysis by the above method.

Table 11 shows the composition analysis results of the phosphors of Examples 29 and 30.

When the value of the composition analysis is converted into the composition formula, Example 29 is Sr _0.75 Ca _0.20 Eu _0.05 Si _3.57 Al _1.41 N _6.33 O _0.46 , and Example 30 is Sr _{0. .67} Ca _0.28 Eu _0.05 Si _3.33 Al _1.73 N _6.13 O _0.74 , confirming that a phosphor having a substantially aimed composition (prepared composition) was obtained.

[Semiconductor light-emitting device simulation]
[Examples 18 to 28 and Comparative Examples 4 to 6]
The phosphor of the above-described embodiments 18-28, Comparative Example 4 is Ca- alpha sialon, Comparative Example 5 _Sr 1.98 BaSiO _5: the _{Eu 0.02,} Comparative Example 6 is yttrium-aluminum-garnet fluorescent material A simulation was performed on the assumption that a semiconductor light emitting device was manufactured by combining with a blue LED (emission peak wavelength 455 nm). The Ca-alpha sialon used in Comparative Example 4 is a known one. Further, _Sr 1.98 BaSiO ₅ used in Comparative Example 5: _{Eu 0.02} is, _Sr 1.98 BaSiO ₅ by powder X-ray measurement: it was confirmed _{that Eu 0.02} is obtained. Further, the yttrium aluminum garnet phosphor used in Comparative Example 6 is P46-Y3 manufactured by Mitsubishi Chemical Corporation. The phosphor of Example 18 is the phosphor of Example 14 described above, the phosphor of Example 19 is the phosphor of Example 15 described above, and the phosphor of Example 22 is the fluorescence of Example 16 described above. It is the same as the body.

The simulation was performed by the following method.
(Simulation method)
An emission spectrum obtained by subtracting the spectrum of the excitation light source from the actual measurement data of the blue LED (peak wavelength: 450 nm, half-value width: 21 nm) and the actual emission spectrum of the phosphor used at a wavelength of 455 nm was prepared. The emission peak intensity of each prepared spectrum is normalized to 1, and the spectrum obtained by multiplying the intensity of the blue LED and the emission peak intensity of the phosphor by an arbitrary ratio is added to obtain a white spectrum. As derived.

The calculation method of each optical characteristic evaluation item was as follows.
(I) The xy chromaticity coordinates on the CIE 1931 chromaticity diagram were calculated based on JIS Z8724: 1997 (title: color measurement method—light source color—).
(Ii) Based on the result of (i) above, after conversion to uv chromaticity coordinates on the CIE 1960 UCS chromaticity diagram, JIS Z8725: 1999 (title: measurement of light source distribution temperature and color temperature / correlated color temperature) Method) The correlated color temperature (Kelvin) and Duv were calculated.
(Iii) The color rendering index (Ra, R1 to R15) was calculated from the white spectrum based on JIS Z8726: 1990 (title: color rendering property evaluation method of light source).

Table 12 shows the chromaticity, correlated color temperature, and Duv values calculated from the white spectrum created by simulation for the light emitting devices using the phosphors of Examples 18 to 28 and Comparative Examples 4 to 6.

In the light emitting device of Comparative Example 4, since the half-value width of the phosphor used was as narrow as 95 nm or less, the color rendering index Ra was as low as 57, and there was a problem in terms of color rendering properties. Since the full width at half maximum is 95 nm or more, the color rendering properties of the light emitting device are improved.
In other words, the light emitting device of the present invention can provide a phosphor having a wide half-value width according to the present invention, so that it is possible to provide a light emitting device having good color rendering and white to light bulb color. .

Further, the correlated color temperature and the color rendering index Ra of the light emitting device of Comparative Example 4 are described in Non-Patent Document 1 (Proceedings of the IEICE General Conference, 2005, Electronics (2), 42, 2005-03-07). The correlation color temperature of the light-emitting device described in 1 and the color rendering index Ra were almost the same, indicating the validity of the simulation used for creating the emission spectrum of the light-emitting device of the example.
In the light emitting device of Comparative Example 5, the half width of the phosphor used is narrow, and the emission peak wavelength is too long as 594 nm, so the correlated color temperature is 1942K. It is not possible. On the other hand, in the light emitting devices of Examples 18 to 28, since the emission peak wavelength of the phosphor to be used is on the short wavelength side, it is possible to provide a light emitting device with good color rendering and white to light bulb color.

In the light emitting device of Comparative Example 6, the correlated color temperature of the phosphor used is about 5500K, and the blue LED and this phosphor alone cannot be a white to light bulb color (2600K to 4500K) light emitting device.
In Examples 18 to 23, it was confirmed that a light emitting device having good color rendering properties and a light emitting color of white to light bulb color (4500K to 2600K) could be provided. This is because the emission peak wavelength can be adjusted while maintaining the feature that the phosphor of the present invention to be used has a wide half-value width of the emission spectrum. In the simulation results, the color rendering index Ra of the light emitting device of Example 18 is 7 points higher than that of Comparative Example 4, and the color rendering index Ra of Examples 19 to 23 is equivalent to that of Example 18. Or it increased within the range of plus 6 points.

Further, in the light emitting devices of Examples 24 to 28, although the correlated color temperature is about the same as that of Example 18, in the simulation result, the value of the color rendering index Ra is higher than that of Example 18 in Examples 24, 25, 26, It increased by 1 or 2 points in the order of 27 and 28. This is because the full width at half maximum of the emission spectrum can be widened by replacing the Sr site of the phosphor used in the light emitting device with Ba. As a result, it is possible to provide a light-emitting device having a light bulb color (2600K to 3250K) with good color rendering.

[Light emitting device]
[Example 31]
Regarding the light emitting device simulated in Example 18 described above, a surface-mounted white light emitting device having the configuration shown in FIG. 2B was actually manufactured by the following procedure, and the light emission characteristics were measured. Of the constituent elements of the present embodiment, the constituent elements corresponding to those shown in FIG. 2B are indicated by parentheses as appropriate.

As the first light emitter (22), an InGaN light emitting diode (manufactured by Showa Denko KK), which is a blue light emitting diode (hereinafter referred to as “blue LED” where appropriate) that emits light at a wavelength of 450 nm to 470 nm, was used. This blue LED (22) was die-bonded to the electrode (27) at the bottom of the recess of the frame (24) using a silver paste as an adhesive. At this time, the silver paste as the adhesive was thinly and uniformly applied in consideration of the heat dissipation of the heat generated in the blue LED (22). After heating at 150 ° C. for 2 hours to cure the silver paste, the blue LED (22) and the electrode (26) of the frame (24) were wire-bonded. A gold wire having a diameter of 25 μm was used as the wire (25).

The phosphor 18 described above was used as the luminescent material of the phosphor-containing part (23). Phosphor slurry obtained by mixing the phosphor 18, the organically modified silicone resin (SCR 1011 manufactured by Shin-Etsu Silicone), and Aerosil (RX-200 manufactured by Nippon Aerosil Co., Ltd.) in a weight ratio of 15.5: 85.5: 2. (Phosphor-containing composition) was prepared. The purpose of using Aerosil is to prevent sedimentation of the phosphor in the resin.

The obtained phosphor slurry is poured into the recesses of the frame (24) and cured by heating at 100 ° C. for 3 hours and further at 140 ° C. for 3 hours to form the phosphor-containing portion (23), and the surface A mounting type white light emitting device was produced.
Further, the obtained light emitting device was driven to emit light at 25 ° C. by applying a current of 20 mA to the blue LED (22). All the light emission from the white light emitting device was received by an integrating sphere, and further introduced into a spectroscope by an optical fiber, the emission spectrum and the total luminous flux were measured, and the white chromaticity coordinates were measured. Specifically, in a room maintained at a temperature of 25 ± 1 ° C, the emission spectrum is measured by energizing 20 mA using Ocean Optics color / illuminance measurement software and USB2000 series spectroscope (integral sphere specification). , It was confirmed that it emitted light bulb color. From the obtained emission spectra, the correlated color temperature was calculated in the same manner as in Examples 18 to 28 and Comparative Examples 4 to 6, and it was 2773K.

The phosphor of the present invention can be used in any field where light is used. For example, in addition to indoor and outdoor lighting, image display of various electronic devices such as mobile phones, household appliances, and outdoor installation displays. It can be suitably used for an apparatus or the like.

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 electrode 27 electrode

Claims

The following formula [1]:
(A 1-x , Eu x ) a D b E c N d O e [1]
(In the formula [1], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d and e are respectively
0.7 ≦ a ≦ 1.3
2.8 ≦ b ≦ 4.0
1.0 ≦ c ≦ 3.0
4.0 ≦ (b + c) /a≦6.0
5.0 ≦ d ≦ 7.0
0 <e ≦ 2.0
6.5 ≦ (d + e) /a≦7.5
Indicates the number that satisfies )
The crystal phase of the crystal phase is orthorhombic or monoclinic, and the unit lattice volume (V) of the crystal phase calculated from the lattice constant is 1220 × 10 6. An oxynitride phosphor characterized by being 6 pm 3 or more and 1246 × 10 6 pm 3 or less.
The phosphor according to claim 1, wherein a space group of the crystal phase is Pna2 1 .
3. The phosphor according to claim 1, wherein, in the formula [1], a ratio of Ca to the entire element A is 0.001 mol% or more and 80 mol% or less.
The phosphor according to any one of claims 1 to 3, wherein the emission peak exists in a wavelength range of 550 nm to 650 nm.
The following formula [1]:
(A 1-x , Eu x ) a D b E c N d O e [1]
(In the formula [1], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d and e are respectively
0.7 ≦ a ≦ 1.3
2.8 ≦ b ≦ 4.0
1.0 ≦ c ≦ 3.0
4.0 ≦ (b + c) /a≦6.0
5.0 ≦ d ≦ 7.0
0 <e ≦ 2.0
6.5 ≦ (d + e) /a≦7.5
Indicates the number that satisfies )
A crystal phase of the crystal phase is orthorhombic or monoclinic, and an emission peak exists in a wavelength range of 581 nm to 650 nm. Oxynitride phosphor.
The phosphor according to claim 5, wherein the space group of the crystal phase is Pna2 1 .
7. The phosphor according to claim 5, wherein, in the formula [1], a ratio of Ca to the entire element A is 0.001 mol% or more and 80 mol% or less.
Following formula [2]:
(A 1-x , Eu x ) a D b E c N d O e [2]
(In the formula [2], A represents an alkaline earth metal element essential for Sr and Ca, D represents a tetravalent metal element essential for Si, and E represents a trivalent metal essential for Al. Represents an element, x represents a number satisfying 0.0001 ≦ x ≦ 0.20, and a, b, c, d and e are respectively
0.7 ≦ a ≦ 1.3
2.8 ≦ b ≦ 3.6
1.0 ≦ c ≦ 3.0
4.0 ≦ (b + c) /a≦6.0
5.0 ≦ d ≦ 7.0
0 <e ≦ 2.0
6.5 ≦ (d + e) /a≦7.3
Indicates the number that satisfies )
The ratio of Ca to element A in [2] above is 0.001 mol% or more and 80 mol% or less, and the crystal system of the crystal phase is orthorhombic or An oxynitride phosphor characterized by being monoclinic.
The phosphor according to claim 8, wherein a space group of the crystal phase is Pna2 1 .
The phosphor according to claim 8 or 9, wherein the emission peak exists in a wavelength range of 570 nm to 600 nm.
The phosphor according to any one of claims 1 to 10, wherein the half-value width of the emission peak is 95 nm or more.
A phosphor-containing composition obtained by dispersing at least one phosphor according to any one of claims 1 to 11 in a liquid medium.
A light emitting device having a first light emitter (excitation light source) and a second light emitter capable of emitting visible light by converting light from the first light emitter, the second light emitter. The phosphor according to claim 12 contains at least one of the phosphors according to any one of claims 1 to 11 as a first phosphor, or the fluorescence according to claim 12 as the second phosphor. A light-emitting device comprising a body-containing composition.
14. The light emitting device according to claim 13, wherein the second light emitter contains at least one kind of phosphor having a light emission peak wavelength different from that of the first phosphor as the second phosphor.
15. The light emitting device according to claim 13 or 14, wherein the correlated color temperature is 2600K or more and 4500K or less.
An illumination device or an image display device comprising the light emitting device according to any one of claims 13 to 15.