JP2008075080A - Light emitting apparatus, image displaying apparatus, and illuminating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting apparatus that attains a high luminance using a Tb complex fluorescent substance. <P>SOLUTION: The light emitting apparatus 1 is equipped with a first illuminant 3 that is a semiconductor light emitting device such as a light emitting diode and a second illuminant 4 that emits visible light by light irradiation from the first illuminant 3, wherein the second illuminant 4 contains a complex fluorescent substance containing Tb and an inorganic fluorescent substance. The complex fluorescent substance has an emission peak wavelength ranging from 510 to 560 nm and the inorganic fluorescent substance has an emission peak wavelength ranging from 570 to 700 nm or 420 to 480 nm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device, and an image display device and an illumination device using the light emitting device.

  In recent years, light emitting devices using phosphors have been developed, and accordingly, research and development on phosphors have been actively conducted. Under such circumstances, non-patent documents 1 and 2 report Tb complex phosphors as phosphors containing Tb. In these documents, the light emission characteristics in a methanol solution are investigated, and it is described that the Tb complex phosphor emits light having a wavelength of 545 nm by excitation with light having a wavelength of 380 nm.

“Rare Earth RARE EARTHS” Japan Rare Earth Society, 2005.5, No. 46, p. 106-107 Proceedings of the 18th Photochemical Conference on Coordination Compounds, p. 61-62

However, when a light-emitting device is to be manufactured using a phosphor containing Tb, including the Tb complex phosphors described in Non-Patent Documents 1 and 2, the conventional technology has not provided sufficient luminance for practical use. .
The present invention was devised in view of the above problems, and aims to provide a light emitting device having high luminance using a Tb complex phosphor, and an image display device and an illumination device using the light emitting device. To do.

  As a result of intensive studies to solve the above problems, the present inventors have obtained a high-luminance light-emitting device by constructing a light-emitting device by combining a Tb complex phosphor and an inorganic phosphor when producing a light-emitting device. The present invention has been completed.

  That is, the gist of the present invention is a light emitting device including a first light emitter and a second light emitter that emits visible light when irradiated with light from the first light emitter, the second light emission. The light emitting device is characterized in that the body contains a complex phosphor containing Tb and an inorganic phosphor (Claim 1).

At this time, it is preferable that the second luminous body contains two or more kinds of the inorganic phosphors (claim 2).
The complex phosphor has an emission peak in a wavelength range of 510 nm to 560 nm, and at least one of the inorganic phosphors has an emission peak in a wavelength range of 570 nm to 700 nm or a wavelength range of 420 nm to 480 nm. (Claim 3).

（式（II）において、Ｒ¹〜Ｒ⁵は、それぞれ独立に、水素原子又は１価の置換基を表わし、Ｙ¹は−ＯＨを表わし、Ｙ²は＝Ｏを表わす。）
Ｌｎは、それぞれ独立に、希土類イオンを表わし、且つ、Ｌｎの少なくとも１つはテルビウムイオンを表わし、Ｘは陰イオンを表わし、ａ、ｂ及びｃは、１≦ａ／ｂ≦４、１＜ｃ／ｂ≦４を満たす整数を表わす。また、Ｙ¹及びＹ²は、同一の又は異なるＬｎに配位している。｝ Furthermore, the complex phosphor is preferably represented by the following formula (I).
L _a (Ln) _b X _c (I)
{In Formula (I), L represents a ligand represented by Formula (II);

(In Formula (II), R ^{1 to} R ⁵ each independently represents a hydrogen atom or a monovalent substituent, Y ¹ represents —OH, and Y ² represents ═O.)
Ln each independently represents a rare earth ion, and at least one of Ln represents a terbium ion, X represents an anion, a, b and c are 1 ≦ a / b ≦ 4, 1 <c An integer satisfying / b ≦ 4 is represented. Y ¹ and Y ² are coordinated to the same or different Ln. }

Another subject matter of the present invention lies in an image display device comprising the light-emitting device as a light source (Claim 5).
Still another subject matter of the present invention lies in an illuminating device comprising the light emitting device as a light source (claim 6).

  ADVANTAGE OF THE INVENTION According to this invention, the high-intensity light-emitting device using Tb complex fluorescent substance, and the image display apparatus and illuminating device using the light-emitting device can be provided.

Hereinafter, the present invention will be described in detail with reference to embodiments and examples, but the present invention is not limited to the following embodiments and examples, and may be arbitrarily changed without departing from the gist of the present invention. Can be implemented.
Further, in the following description, there is a part for explaining the phosphor, but in the explanation part, phosphors that are different only in a part of the structure are appropriately omitted. For example, “Y ₂ SiO ₅ : Ce ³⁺ ”, “Y ₂ SiO ₅ : Tb ³⁺ ” and “Y ₂ SiO ₅ : Ce ³⁺ , Tb ³⁺ ” are changed to “Y ₂ SiO ₅ : Ce ³⁺ , Tb”. ³⁺ ”,“ La ₂ O ₂ S: Eu ”,“ Y ₂ O ₂ S: Eu ”and“ (La, Y) ₂ O ₂ S: Eu ”are changed to“ (La, Y) ₂ O ₂ S: “Eu” collectively. In this case, the total of the elements in () is 1 mol. Omitted parts are shown separated by commas (,).

  The light-emitting device of the present invention includes at least a first light-emitting body as an excitation light source and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body.

[1. First luminous body]
The 1st light-emitting body in the light-emitting device of this invention light-emits the light which excites the 2nd light-emitting body mentioned later. The emission 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. An illuminant having an emission wavelength from the near ultraviolet region to the blue region is used. As a specific numerical value, an illuminant having an emission peak wavelength of usually 200 nm or more, preferably 300 nm or more, more preferably 360 nm or more, and usually 500 nm or less, preferably 480 nm or less, more preferably 470 nm or less is used. As the first light emitter, a semiconductor light emitting element is generally used. Specifically, a light emitting diode (hereinafter abbreviated as “LED” as appropriate) or a semiconductor laser diode (semiconductor laser diode). Hereinafter, it is abbreviated as “LD” where appropriate).

Among these, as the first light emitter, a GaN-based LED or LD using a GaN-based compound semiconductor is preferable. This is because GaN-based LEDs and LDs have remarkably large light output and external quantum efficiency compared to SiC-based LEDs that emit light in this region. This is because bright light emission can be obtained. For example, for a current load of 20 mA, GaN-based LEDs and LDs usually have a light emission intensity 100 times or more that of SiC-based. A GaN-based LED or LD preferably has an Al _x Ga _Y N light emitting layer, a GaN light emitting layer, or an In _x Ga _Y N light emitting layer. Among GaN-based LEDs, those having an In _X Ga _Y N light-emitting layer are particularly preferable because the emission intensity is very strong. In GaN-based LEDs, an In _X Ga _Y N layer and a GaN layer are particularly preferable. A multi-quantum well structure is particularly preferable because the emission intensity is very strong.

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

These light-emitting layer GaN-based LED is, p layer, n layer, electrode, and is obtained by the basic components of the substrate, Al _X Ga _Y N layer of the light-emitting layer n-type and p-type, 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 of a quantum well structure are more preferable because of high light emission efficiency.

[2. Second luminous body]
The second light emitter in the light emitting device of the present invention is a light emitter that emits visible light when irradiated with light from the first light emitter described above, and is a complex phosphor containing Tb (hereinafter referred to as “Tb complex fluorescence as appropriate”). Body) and an inorganic phosphor.

[2-1. Tb complex phosphor]
The Tb complex phosphor is not particularly limited as long as it is a complex phosphor containing Tb, and an arbitrary one can be used. Among them, a Tb complex phosphor represented by the following formula (I) (hereinafter referred to as “specific” "Tb phosphor" is preferred. This specific Tb phosphor is a light-emitting rare earth multinuclear complex in which a ligand molecule (sensitizer) having a photosensitizing function is coordinated with a plurality of rare earth ions serving as nuclei.
L _a (Ln) _b X _c (I)

  In the formula (I), a, b and c represent integers satisfying 1 ≦ a / b ≦ 4 and 1 <c / b ≦ 4. When a suitable range of a, b and c is mentioned, a is usually an integer of 2 or more, preferably 3 or more, more preferably 5 or more, and usually 40 or less, preferably 30 or less, more preferably 20 or less. Represent. B represents an integer of usually 2 or more, preferably 5 or more, more preferably 10 or more, and usually 20 or less, preferably 18 or less, more preferably 16 or less. Furthermore, c represents an integer of usually 1 or more, preferably 3 or more, more preferably 5 or more, and usually 40 or less, preferably 30 or less, more preferably 19 or less.

In the formula (I), Ln represents a rare earth ion. This Ln is presumed to form the nucleus of a specific Tb complex that is a multinuclear complex. However, at least one of Ln represents a terbium ion. At this time, the terbium ion is usually a trivalent cation.
Examples of suitable Ln include europium divalent cation (Eu ²⁺ ), lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, Lanthanoid trivalent cations such as lutetium (La ³⁺ , Ce ³⁺ , Pr ³⁺ , Nd ³⁺ , Pm ³⁺ , Sm ³⁺ , Eu ³⁺ , Gd ³⁺ , Tb ³⁺ , Dy ³⁺ , Ho ³⁺ , Er ³⁺ , Tm ³⁺ , Yb ³⁺ , Lu ³⁺ ), and a cation such as a cerium tetravalent cation (Ce ⁴⁺ ).

  Note that Ln may consist of only one of these rare earth ions, or two or more rare earth ions may be used in any combination and ratio without departing from the gist of the present invention. . Since the light emission characteristics and the like vary depending on the type of rare earth ions Ln, it is preferable to select them according to the purpose.

In the formula (I), X represents an anion. Examples of X include ions that connect rare earth ions Ln such as O ²⁻ , OH ⁻ , S ²⁻ , SH ⁻ , Se ²⁻ , Te ²⁻ ; NO ₃ ⁻ , Cl ⁻ , Br ⁻ , OH ⁻ , B (C ₆ H ₅ ) ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ^{−, and the} like, which are part of the composition, may be mentioned. In addition, 1 type may be used for X and it may use 2 or more types together by arbitrary combinations and a ratio.

In the formula (I), L represents a ligand represented by the formula (II). This ligand is presumed to function as a photosensitizer that transfers the energy of irradiated light to the rare earth ions Ln.

In formula (II), R ^{1 to} R ⁵ each independently represents a hydrogen atom or a monovalent substituent. Examples of monovalent substituents that can be R ^{1 to} R ⁵ include hydroxyl groups; substituted or unsubstituted amino groups; nitro groups; halogen groups such as chloro groups and bromo groups. Examples of monovalent substituents that can be R ^{1 to} R ⁵ include aromatic groups containing heteroatoms such as thienyl and pyridyl groups; benzyl groups; branched chains such as isopropyl groups and 2-ethyl-hexyl groups. An alkyl group having a structure; a substituted or unsubstituted aryl group; a cyano group; an alkyl group or cycloalkyl group represented by —R; an alkoxy group represented by —OR; an acyl group represented by —C (═O) R; An organic group such as an amide group represented by —C (═O) NHR is also included.

Here, when R < ¹ > -R < ⁵ > is an alkyl group, a methyl group, an ethyl group, a hexyl group etc. are mentioned as the example. Further, when R ^{1 to} R ⁵ are aryl groups, examples thereof include a phenyl group, a tolyl group, a xylyl group, a biphenyl group, a naphthyl group, an anthryl group, and a phenanthryl group.

Moreover, the substituent which substitutes the thing which may be substituted among said R < ¹ > -R < ⁵ > is arbitrary, unless the effect of this invention is impaired remarkably, For example, an alkyl group, a halogen, a nitro group, A cyano group, an alkoxy group, an acyl group, etc. are mentioned. In addition, only 1 type may be sufficient as the substituent substituted by these R < ¹ > -R < ⁵ >, and 2 or more types may be used together by arbitrary combinations and a ratio.

The carbon number of R ^{1 to} R ⁵ is arbitrary as long as the effects of the present invention are not significantly impaired, but is usually 1 or more, preferably 2 or more, more preferably 5 or more, and usually 20 or less, preferably 18 or less, more preferably 15 or less. If the number of carbon atoms is too small or too large, the luminance may decrease.

In formula (II), Y ¹ represents —OH, and Y ² represents ═O. In the ligand L, Y ¹ and Y ² are coordinated to the rare earth ion Ln, whereby the ligand L and the rare earth ion Ln are coordinated. As for the coordination form, both Y ¹ and Y ² may be coordinated to the same rare earth ion Ln, or Y ¹ and Y ² may be coordinated to different rare earth ions Ln. .

The ligand L preferably has the following structure.
In the formula (II), R ¹ and / or R ³ are preferably hydrogen, and R ¹ and R ³ are particularly preferably both hydrogen. That is, R ¹ present in the ortho position relative to Y ¹ and R ³ present in the para position relative to Y ¹ are preferably not substituted.
R ⁵ represents an alkyl group or cycloalkyl group represented by —R, an alkoxy group represented by —OR, an acyl group represented by —C (═O) R, or an amide group represented by —C (═O) NHR. And is more preferably an alkyl group or a cycloalkyl group represented by -R, or an alkoxy group represented by -OR. Here, R is a substituted or unsubstituted linear or branched alkyl group or cycloalkyl group. The number of carbon atoms of R is arbitrary as long as the effects of the present invention are not significantly impaired, but are preferably 2 or more, more preferably 5 or more, and preferably 20 or less, more preferably 18 or less. The substituent for R is optional as long as the effects of the present invention are not significantly impaired. Preferred specific examples include a hydroxyl group (—OH), an alkoxy group (—OR), an amino group (—NH ₂ ), and the like. And an electron donating group.
When the ligand L has a structure as described above, a pair of L benzene rings cause ππ stacking (pipa stacking) in the complex, and the complex easily takes a stable structure. As a result, the emission intensity is considered to be improved.

Among these ligands L, it is preferable to use hexyl salicylate represented by the following formula (III) because high emission intensity can be obtained and synthesis is easy.

Since the above-mentioned Tb phosphor composed of hexyl salicylate has a characteristic that the absorption spectrum is around 390 nm, it can be efficiently excited by light from a commercially available inexpensive LED or the like. Furthermore, it has the advantages that it is much easier to synthesize and less expensive than the ligands of the rare earth complexes conventionally used.
For the same reason as described above, as the ligand L, methyl salicylate, ethyl salicylate, propyl salicylate, butyl salicylate, pentyl salicylate, hydroxyethyl salicylate, ethylhexyl salicylate, or the like can also be used.

  The specific Tb phosphor described above has an advantage that the emission intensity is remarkably higher than that of other phosphors. Moreover, this specific Tb phosphor can be efficiently excited using a commercially available inexpensive LED. Further, the specific Tb phosphor has high thermal durability. Moreover, there is an advantage that the synthetic raw material is inexpensive. In addition, since the light-emitting rare earth polynuclear complex itself is colorless and transparent, it can be easily integrated with other substances and materials.

Further, among the specific Tb phosphors described above, in particular, a nine-nuclear rare earth polynuclear complex (hereinafter, appropriately referred to as “nine-nuclear rare earth complex”) having a complex structure represented by L ₁₆ (Ln) ₉ X _c is used. preferable. FIG. 4 shows a schematic conceptual diagram of the molecular structure of the nine-nuclear rare earth complex in this case. In addition, the energy transfer described in FIG. 4 represents that the light energy captured by the ligand L moves to the rare earth ions Ln (nuclei). In this case, the ligand L coordinates to the outer eight of the nine rare earth ions Ln (nuclei). At this time, all of the rare earth ions Ln are terbium trivalent cations or a combination of at least one terbium trivalent cation and trivalent cations of samarium, europium, gadolinium, and ytterbium. Are preferably used.

  Furthermore, it is particularly preferable to use only a terbium ion as the rare earth ion Ln serving as the nucleus of the nine-nuclear rare earth complex. At this time, hexyl salicylate is preferably used as the ligand L. Thus, by using only terbium ions as rare earth ions and using hexyl salicylate as a ligand, the nine-nuclear rare earth complex can have thermal durability and realize green light emission with high emission intensity. can do. Further, yellow light emission can be realized by combining terbium ions and europium ions as the rare earth ions Ln. Thus, light emission of a desired color can be obtained by appropriately combining various rare earth ions.

  In addition, Tb complex fluorescent substance may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

[Emission peak of Tb complex phosphor]
Although there is no restriction | limiting in the wavelength range of the light emission peak of Tb complex fluorescent substance, Usually, it is a visible region. The specific wavelength range of the emission peak is usually 510 nm or more, preferably 520 nm or more, and usually 700 nm or less, preferably 690 nm or less. In particular, when a Tb complex phosphor that emits green light is used, the wavelength range of the emission peak is usually 510 nm or more, preferably 520 nm or more, and usually 560 nm or less, preferably 550 nm or less. The specific Tb phosphor is a green phosphor having an emission peak in this wavelength range.

[Weight median diameter of Tb complex phosphor]
The weight median diameter of the Tb complex phosphor is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 1 μm or more, especially 2 μm or more, particularly 5 μm or more, and usually 30 μm or less, especially 20 μm or less, particularly 10 μm or less. It is preferable that When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, when the weight median diameter is too large, there is a tendency for coating unevenness and blockage of a dispenser to occur.

[Content of Tb complex phosphor]
The content of the Tb complex phosphor in the second light emitter is arbitrary as long as the effects of the present invention are not significantly impaired, but usually 5% by weight or more, preferably 10% by weight or more, more preferably 15% by weight or more, Moreover, it is 50 weight% or less normally, Preferably it is 40 weight% or less, More preferably, it is 30 weight% or less. If the amount of the Tb complex phosphor is too small, leakage of excitation light may occur and the luminance may decrease. If the amount is too large, applicability may be deteriorated, or light may be scattered in the apparatus, so that light can be extracted. The efficiency may decrease and the luminance may decrease.

[2-2. Inorganic phosphor]
There is no restriction | limiting in an inorganic fluorescent substance, According to the use etc. of a light-emitting device, arbitrary inorganic fluorescent substances can be used. For example, a phosphor that emits fluorescence of the same color as the Tb complex phosphor (a phosphor of the same color) may be used, or a phosphor that emits fluorescence of a color different from that of the Tb complex phosphor may be used. However, since the inorganic phosphor is usually used to adjust the color tone of light emitted from the second phosphor, a phosphor that emits fluorescence having a color different from that of the Tb complex phosphor is often used. Therefore, usually, a phosphor having an emission wavelength different from that of the Tb complex phosphor is often used as the inorganic phosphor.

  Although only one type of inorganic phosphor may be used, it is preferable to use two or more types. Moreover, when using 2 or more types of inorganic fluorescent substance, the combination and ratio are arbitrary, However, It is preferable to use combining the inorganic fluorescent substance from which the light emission color differs. Increasing the color component of light emitted by the light emitting device of the present invention, making the light more natural when the light emitting device is used for illumination, or providing color reproducibility when the light emitting device is used for an image display device It is for improving.

Among the inorganic phosphors, metal oxides represented by Y ₂ O ₃ and Zn ₂ SiO ₄ which are crystal bases, metal nitrides represented by Sr ₂ Si ₅ N _{8 and the} like, Ca ₅ (PO ₄ ) ₃ Phosphate represented by Cl, etc. and sulfides represented by ZnS, SrS, CaS, etc., and rare earths such as Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb A combination of metal ions and metal ions such as Ag, Cu, Au, Al, Mn, and Sb as activators or coactivators is preferred.

Preferable specific examples of the crystal matrix include, for example, sulfides such as (Zn, Cd) S, SrGa ₂ S ₄ , SrS, CaS and ZnS, oxysulfides such as Y ₂ O ₂ S, (Y, Gd) ₃ Al ₅ O ₁₂ , YAlO ₃ , BaMgAl ₁₀ O ₁₇ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ , (Ba, Sr, Ca) (Mg, Zn, Mn) Al ₁₀ O ₁₇ , BaAl ₁₂ O ₁₉ , CeMgAl ₁₁ O ₁₉ , (Ba, Sr, Mg) O · Al ₂ O ₃ , BaAl ₂ Si ₂ O ₈ , SrAl ₂ O ₄ , Sr ₄ Al ₁₄ O ₂₅ , Y ₃ Al ₅ O _12, etc. Salt, silicate such as Y ₂ SiO ₅ and Zn ₂ SiO ₄ , oxide such as SnO ₂ and Y ₂ O ₃ , borate such as GdMgB ₅ O ₁₀ and (Y, Gd) BO ₃ , Ca ₁₀ (PO _{4 ) 6 (F, Cl) 2} , (Sr, Ca, Ba, Mg) 10 (PO 4) 6 halophosphate such as Cl _{2 Sr 2 P 2 O 7, (} La, Ce) phosphate PO ₄ etc., (Mg, Ca, Sr, Ba) 2 Si 5 N 8, (Mg, Ca, Sr, Ba) AlSiN 3 such metal nitride And the like.

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

  Specifically, the following red inorganic phosphors, green inorganic phosphors, blue inorganic phosphors, yellow inorganic phosphors, and the like can be used as the phosphors, but these are merely examples and are used in the present invention. The phosphors that can be used are not limited to these.

[Red inorganic phosphor]
Among the inorganic phosphors, the red inorganic phosphor that emits red light includes, for example, broken particles having a red fracture surface and emits light in the red region (Mg, Ca, Sr, Ba) ₂ Si ₅ N _8. : Europium-activated alkaline earth silicon nitride-based phosphor represented by Eu, composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the red region (Y, La, Gd, Lu) ) ₂ O ₂ S: Europium activated rare earth oxychalcogenide phosphor represented by Eu.

  Further, for example, an oxynitride containing at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta, W, and Mo described in JP-A-2004-300247 and / or Alternatively, a phosphor containing an oxysulfide and containing an oxynitride having an alpha sialon structure in which a part or all of the Al element is substituted with a Ga element can also be used in this embodiment. . These are phosphors containing oxynitride and / or oxysulfide.

In addition, examples of the red inorganic phosphor include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu, Y (V, P) O ₄ : Eu, Y ₂ O _3. : Eu activated oxide phosphor such as Eu, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Mg) ₂ SiO ₄ : Eu, Mn activated silicate such as Eu, Mn Eu-activated tungstic acid such as phosphor, LiW ₂ O ₈ : Eu, LiW ₂ O ₈ : Eu, Sm, Eu ₂ W ₂ O ₉ , Eu ₂ W ₂ O ₉ : Nb, Eu ₂ W ₂ O ₉ : Sm Salt phosphor, Eu activated sulfide phosphor such as (Ca, Sr) S: Eu, Eu activated aluminate phosphor such as YAlO ₃ : Eu, LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu, Ca _{2 Y 8 (SiO 4) 6} O 2: Eu, (Sr, Ba, Ca) 3 SiO 5: Eu, Sr 2 BaSiO 5: Eu Eu-like Tsukekatsu珪_{Phosphor, (Y, Gd) 3 Al} 5 O 12: Ce, (Tb, Gd) 3 Al 5 O 12: Ce -activated aluminate phosphor such as Ce, (Ca, Sr, Ba ) 2 Si 5 _{N 8: Eu, (Mg,} Ca, Sr, Ba) SiN 2: Eu, (Mg, Ca, Sr, Ba) AlSiN 3: Eu -activated nitride phosphor such as Eu, (Mg, Ca, Sr , Ba ) AlSiN ₃ : Ce-activated nitride phosphor such as Ce, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn-activated halophosphate phosphor such as Eu and Mn, 2. Ba ₃ Mg) Si ₂ O ₈ : Eu, Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu, Mn activated silicate phosphor such as Eu, Mn _{5MgO · 0.5MgF 2 · GeO 2:} Mn -activated germanate salt phosphor such as Mn, with Eu such as Eu-activated α-sialon Oxynitride phosphor, (Gd, Y, Lu, La) 2 O 3: Eu, Eu Bi, etc., Bi-activated oxide phosphor, (Gd, Y, Lu, La) 2 O 2 S: Eu, Eu, Bi-activated oxysulfide phosphors such as Bi, (Gd, Y, Lu, La) VO ₄ : Eu, Bi-activated vanadate phosphors such as Eu, Bi, SrY ₂ S ₄ : Eu, Ce Eu, Ce activated sulfide phosphor such as CaLa ₂ S ₄ : Ce activated sulfide phosphor such as (Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba) , Mg, Zn) ₂ P ₂ O ₇ : Eu, Mn-activated phosphate phosphor such as Eu, Mn, (Y, Lu) ₂ WO ₆ : Eu, Mo-activated tungstate fluorescence such as Eu, Mo body, (Ba, Sr, Ca) x Si y N z: Eu, Ce ( provided that, x, y, z are an integer of 1 or more), such as Eu, Ce-activated nitride firefly Body, (Ca, Sr, Ba, Mg) 10 (PO 4) 6 (F, Cl, Br, OH): Eu, Eu such as Mn, Mn-activated halophosphate phosphor, ((Y, Lu, Gd , Tb) _1-x Sc _x Ce _y ) ₂ (Ca, Mg) _1-r (Mg, Zn) _{2 + r} Si _zq Ge _q O _{12 + δ,} etc. Ce-activated silicate phosphor, (Sr, Mg ) ₃ (PO ₄ ) ₂ : Sn ²⁺ Sn-activated phosphate phosphor or the like may be used.

Among the red inorganic phosphors, those having a peak wavelength in the range of 580 nm or more, preferably 590 nm or more, and 620 nm or less, preferably 610 nm or less can be suitably used as the orange inorganic phosphor. Examples of such orange inorganic phosphors include (Sr, Ba) ₃ SiO ₅ : Eu, (Sr, Mg) ₃ (PO ₄ ) ₂ : Sn ^{2+ and the} like.

Among these red inorganic phosphors, particularly suitable red inorganic phosphors for use in combination with Tb complex phosphors are Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu. (Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu, Eu-activated nitride phosphors such as (Mg, Ca, Sr, Ba) AlSiN ₃ : Eu, (Sr, Ba) ₃ SiO ₅ : Eu, etc. Eu-activated silicate phosphors.

[Green inorganic phosphor]
Among the inorganic phosphors, the green inorganic phosphor emitting green light is composed of, for example, fractured particles having a fracture surface, and emits light in the green region (Mg, Ca, Sr, Ba) Si ₂ O ₂ N _2. : Europium-activated alkaline earth silicon oxynitride phosphor represented by Eu, composed of fractured particles having a fracture surface, and emitting in the green region (Ba, Ca, Sr, Mg) ₂ SiO ₄ : Eu Examples thereof include europium-activated alkaline earth silicate phosphors.

In addition, examples of the green inorganic phosphor include Eu-activated aluminate phosphors such as Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu, (Sr, Ba ) Al ₂ Si ₂ O ₈ : Eu, (Ba, Mg) ₂ SiO ₄ : Eu, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, (Ba, Sr, Ca) ₂ (Mg, Zn) Si ₂ O ₇ : Eu, (Ba, Ca, Sr, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Eu-activated silicate phosphor such as Eu, Y ₂ SiO ₅ : Ce, Tb activated silicate phosphor such as Ce, Tb, Sr ₂ P ₂ O ₇ —Sr ₂ B ₂ O ₅ : Eu activated borate phosphate phosphor such as Eu, Sr ₂ Si ₃ O ₈ — 2SrCl ₂ : Eu-activated halosilicate phosphor such as Eu, Zn ₂ SiO ₄ : Mn-activated silicate phosphor such as Mn, CeMgAl ₁₁ Tb activated aluminate phosphors such as O ₁₉ : Tb, Y ₃ Al ₅ O ₁₂ : Tb, Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Tb, La ₃ Ga ₅ SiO ₁₄ : With Tb such as Tb Activated silicate phosphor, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphor such as Eu, Tb, Sm, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, ( Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce-activated aluminate phosphor such as Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ ( Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce-activated silicate phosphor such as Ce, Ce-activated oxide phosphor such as CaSc ₂ O ₄ : Ce, SrSi ₂ O ₂ N ₂ : Eu, (Sr, Ba, Ca) Si 2 O 2 N 2: Eu, Eu -activated β-sialon, Eu Tsukekatsusan nitride firefly such Eu-activated α-sialon _{Body, BaMgAl 10 O 17: Eu,} Eu such as Mn, Mn-activated aluminate phosphor, SrAl ₂ O _4: Eu-activated aluminate phosphor such as Eu, (La, Gd, Y ) 2 O 2 S: Tb-activated oxysulfide phosphors such as Tb, LaPO ₄ : Ce, Tb-activated phosphate phosphors such as Ce, Tb, sulfides such as ZnS: Cu, Al, ZnS: Cu, Au, Al phosphor, (Y, Ga, Lu, Sc, La) BO 3: Ce, Tb, Na 2 Gd 2 B 2 O 7: Ce, Tb, (Ba, Sr) 2 (Ca, Mg, Zn) B 2 O ₆ : Ce, Tb activated borate phosphor such as K, Ce, Tb, Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphor such as Eu, Mn, (Sr, Ca , Ba) (Al, Ga, in) 2 S 4: Eu activated thioaluminate phosphor or thiogallate phosphor such as Eu, _{Ca, Sr) 8 (Mg,} Zn) (SiO 4) 4 Cl 2: Eu, it is also possible to use Eu such as Mn, a Mn-activated halo-silicate phosphors and the like.

Among these green inorganic phosphors, particularly suitable green inorganic phosphors for use in combination with Tb complex phosphors are europium activated alkalis represented by (Ba, Ca, Sr, Mg) ₂ SiO ₄ : Eu. Earth silicate phosphors, BaMgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphors such as Eu, Mn, Eu activated alumina aluminate such as (Ba, Sr, Ca) Al ₂ O ₄ : Eu Phosphor, sulfide phosphor such as ZnS: Cu, Al, Ce activated oxide phosphor such as CaSc ₂ O ₄ : Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na , Li) ₂ Si ₃ O ₁₂ : Ce-activated silicate phosphor such as Ce.

[Blue inorganic phosphor]
Among the inorganic phosphors, the blue inorganic phosphor that emits blue light is, for example, BaMgAl ₁₀ O ₁₇ : Eu composed of grown particles having a substantially hexagonal shape as a regular crystal growth shape and emitting light in a blue region. The europium-activated barium magnesium aluminate-based phosphor, which is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, emits light in the blue region (Ca, Sr, Ba) ₅ (PO ₄ ) ₃ A europium-activated calcium halophosphate phosphor represented by Cl: Eu, composed of grown particles having a substantially cubic shape as a regular crystal growth shape, and emits light in a blue region (Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: europium-activated alkaline earth aluminate phosphor represented by Eu, consists fracture particles having a fracture surface Is, to emit light in the blue-green region (Sr, Ca, Ba) Al 2 O 4: Eu or _{(Sr, Ca, Ba) 4} Al 14 O 25: europium-activated alkaline earth aluminate phosphor represented by Eu Examples include the body.

In addition, as the blue inorganic phosphor, for example, Sn-activated phosphate phosphor such as Sr ₂ P ₂ O ₇ : Sn, Sr ₄ Al ₁₄ O ₂₅ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, BaAl ₈ Eu-activated aluminate phosphors such as O ₁₃ : Eu, Ce-activated thiogallate phosphors such as SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu BaMgAl ₁₀ O ₁₇ : Eu-activated aluminate phosphor such as Eu, Tb, Sm, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn-activated aluminate phosphor such as Eu, Mn, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Ca) ₅ (PO ₄ ) ₃ (Cl, F, Br, OH): Eu, Mn, Sb, etc. Eu-activated halophosphate _{phosphor, BaAl 2 Si 2 O 8:} Eu, ( _{r, Ba) 3 MgSi 2 O} 8: Eu -activated silicate phosphors such as _{Eu, Sr 2 P 2 O 7} : Eu -activated phosphate phosphor such as Eu, ZnS: Ag, ZnS: Ag, Al , etc. Sulfide activated phosphor such as Y ₂ SiO ₅ : Ce activated silicate phosphor, tungstate phosphor such as CaWO ₄ , (Ba, Sr, Ca) BPO ₅ : Eu, Mn, (Sr, Ca ) ₁₀ (PO ₄ ) ₆ · nB ₂ O ₃ : Eu, 2SrO · 0.84P ₂ O ₅ · 0.16B ₂ O ₃ : Eu, Mn-activated boric acid phosphor phosphor such as Eu, Sr ₂ Si ₃ It is also possible to use Eu-activated halosilicate phosphors such as O ₈ · 2SrCl ₂ : Eu.

Among these blue inorganic phosphors, particularly suitable blue inorganic phosphors for use in combination with Tb complex phosphors include Eu-activated aluminate phosphors such as BaMgAl ₁₀ O ₁₇ : Eu.

[Yellow inorganic phosphor]
Among inorganic phosphors, examples of yellow inorganic phosphors that emit yellow light include various oxide-based, nitride-based, oxynitride-based, sulfide-based, and oxysulfide-based phosphors.
In particular, RE ₃ M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M represents Al, Ga, and Sc. And M ² ₃ M ³ ₂ M ⁴ ₃ O ₁₂ : Ce (where M ² is a divalent metal element, M ³ is a trivalent metal element) , M ⁴ represents a tetravalent metal element.) A garnet-based phosphor having a garnet structure represented by AE ₂ M ⁵ O ₄ : Eu (where AE is Ba, Sr, Ca, Mg, And at least one element selected from the group consisting of Zn and M ⁵ represents Si and / or Ge.) Etc., and the constituent elements of the phosphors of these systems An oxynitride phosphor in which part of oxygen is replaced by nitrogen, AEAlSiN ₃ : Ce (this Here, AE represents at least one element selected from the group consisting of Ba, Sr, Ca, Mg and Zn.) Fluorescence activated by Ce such as a nitride-based phosphor having a CaAlSiN ₃ structure such as The body is mentioned.

In addition, examples of the yellow inorganic phosphor include sulfides such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, and (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu. It is also possible to use a phosphor activated by Eu, such as a material phosphor, an oxynitride phosphor having a SiAlON structure such as Cax (Si, Al) ₁₂ (O, N) ₁₆ : Eu.

[Emission peak of inorganic phosphor]
Although there is no restriction | limiting in the wavelength range of the emission peak of inorganic fluorescent substance, Usually, it is a visible region. Although there is no restriction | limiting in the wavelength of a specific emission peak, For example, when the preferable wavelength range of the emission peak of a red inorganic fluorescent substance, a green inorganic fluorescent substance, a blue inorganic fluorescent substance, and a yellow inorganic fluorescent substance is shown, it is as follows. is there.
The wavelength range of the emission peak of the red inorganic phosphor is usually 570 nm or more, preferably 575 nm or more, more preferably 580 nm or more, and usually 700 nm or less, preferably 690 nm or less, more preferably 680 nm or less.
The wavelength range of the emission peak of the green inorganic phosphor is usually 500 nm or more, preferably 510 nm or more, more preferably 520 nm or more, and usually 570 nm or less, preferably 560 nm or less, more preferably 550 nm or less.
The wavelength range of the emission peak of the blue inorganic phosphor 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 470 nm or less.
The wavelength range of the emission peak of the yellow inorganic phosphor is usually 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.

  Among these, regarding the emission peak wavelength, it is preferable to use at least one inorganic phosphor having an emission peak in a wavelength range of 570 nm to 700 nm or a wavelength range of 420 nm to 480 nm. In particular, an inorganic phosphor having an emission peak wavelength in this wavelength range is particularly preferably used in combination with a Tb complex phosphor having an emission peak in the wavelength range of 510 nm or more and 560 nm or less. This is because white light with high luminance can be obtained. In addition to the inorganic phosphor having an emission peak in the above wavelength range, other inorganic phosphors may be used alone or in combination of two or more.

[Weight median diameter of inorganic phosphor]
The weight median diameter of the inorganic phosphor is arbitrary as long as the effects of the present invention are not significantly impaired, but it is usually 10 μm or more, preferably 15 μm or more, and usually 30 μm or less, preferably 20 μm or less.

[Content of inorganic phosphor]
The content of the inorganic phosphor in the second luminous body is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 5% by weight or more, preferably 10% by weight or more, more preferably 15% by weight or more, The amount is usually 50% by weight or less, preferably 40% by weight or less, more preferably 30% by weight or less. If the amount of the inorganic phosphor is too small, excitation light may leak and the luminance may decrease. If the amount is too large, the luminance may decrease or applicability may deteriorate.

[Preferred combinations]
The specific type of inorganic phosphor used in combination with the Tb complex phosphor and the ratio of the inorganic phosphor to the Tb complex phosphor are arbitrary as long as the effects of the present invention are not significantly impaired. Any setting may be made accordingly.

Therefore, in the light emitting device of the present invention, the types of the red inorganic phosphor, the blue inorganic phosphor, the green inorganic phosphor, and the yellow inorganic phosphor described above may be appropriately selected according to the use of the light emitting device. For example, when the light emitting device of the present invention is configured as a white light emitting device, a Tb complex phosphor and an inorganic phosphor may be appropriately combined so that desired white light can be obtained. As a specific example, a near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a specific Tb phosphor is used as the Tb complex phosphor, and a red inorganic phosphor and a blue inorganic are used as the inorganic phosphor. If a phosphor is used in combination, a white light emitting device can be obtained. In this way, when an example of a combination of inorganic phosphors suitable as an inorganic phosphor to be used when a white light emitting device is configured in combination with a specific Tb phosphor, red inorganic phosphors (Mg, Ca, Sr) are given. , Ba) AlSiN ₃ : Eu is preferably used in combination with BaMgAl ₁₀ O ₁₇ : Eu as a blue-emitting inorganic phosphor. As a mixing ratio of each phosphor in this case, when the total amount of the Tb complex phosphor, the blue phosphor and the red phosphor is 100, Tb complex phosphor: blue phosphor: red phosphor = 10 to 80 : 10 to 80: 1 to 20 (weight ratio) is preferable.

[2-3. Sealing resin]
The second illuminant can be composed of only the Tb complex phosphor and the inorganic phosphor, but for example, a sealing resin can also be used. In that case, normally, the Tb complex phosphor and the inorganic phosphor are dispersed in the sealing resin to constitute the second light emitter.

There is no restriction | limiting in particular in sealing resin, As long as the light which the 1st light-emitting body, Tb complex fluorescent substance, and inorganic fluorescent substance can permeate | transmit can be used, unless the effect of this invention is impaired remarkably. . If the example of sealing resin is given, a thermoplastic resin, a thermosetting resin, a photocurable resin etc. will be mentioned. Specifically, methacrylic resin such as methyl polymethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; ethyl cellulose, cellulose acetate, cellulose Cellulose resins such as acetate butyrate; epoxy resins; phenol resins; silicone resins such as addition reaction type silicone resins, condensation reaction type silicone resins, and modified silicone resins. Also, inorganic materials such as inorganic materials obtained by solidifying (curing) a solution obtained by hydrolytic polymerization of a solution containing a metal alkoxide, ceramic precursor polymer or metal alkoxide by a sol-gel method, or a combination thereof. An inorganic material having a siloxane bond can also be used as the sealing resin.
In addition, 1 type may be used for sealing resin and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the sealing resin used in the second luminous body is arbitrary as long as the effects of the present invention are not significantly impaired. The phosphor (Tb complex phosphor) varies depending on the type of the sealing resin and the type of the light emitting device. And a weight ratio with respect to the inorganic phosphor etc.) is usually 0.1 times or more, preferably 3 times or more, more preferably 5 times or more, and usually 30 times or less, preferably 15 times or less. If the amount of the sealing resin is too small, the brightness may be lowered, and if it is too much, the brightness may be lowered or the coating property may be deteriorated.

[2-4. Other ingredients]
The 2nd light-emitting body may contain components other than Tb complex fluorescent substance mentioned above, inorganic fluorescent substance, and sealing resin, unless the effect of this invention is impaired remarkably. Examples of other components include organic phosphors and inorganic particles (light dispersing agents).
In addition, 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and a ratio.

[2-5. Method for manufacturing second light emitter]
Although there is no restriction | limiting in the preparation method of a 2nd light-emitting body, For example, when comprising a 2nd light-emitting body using sealing resin, a phosphor containing composition is prepared first and this phosphor containing composition is used. It can be made by curing.

  The phosphor-containing composition is obtained by dispersing at least a Tb complex phosphor and an inorganic phosphor in a liquid medium, and the liquid medium functions as a sealing resin when cured. In other words, a liquid substance that functions as a sealing resin by curing is used as the liquid medium.

  Any liquid medium may be used as long as it exhibits liquid properties under the desired use conditions, suitably disperses the Tb complex phosphor and the inorganic phosphor, and does not cause an undesirable reaction. It is possible to select according to. Examples of the liquid medium include a thermosetting resin before curing and a photocurable resin, and examples thereof include those similar to those exemplified as the sealing resin. However, when used as a liquid medium, these are used in a liquid state before curing. Furthermore, a solution in which the sealing resin is dissolved in a solvent can be used as the liquid medium. In addition, these liquid media may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  The amount of the liquid medium used may be appropriately adjusted depending on the application, but generally, the weight ratio of the liquid medium to the phosphor (Tb complex phosphor, inorganic phosphor, etc.) is usually 3 times or more, preferably Is 5 times or more, usually 30 times or less, preferably 15 times or less. If the amount of the liquid medium is too small, the luminance may be lowered. If the amount is too large, the luminance may be lowered or the coating property may be deteriorated.

  In addition to the Tb complex phosphor, the inorganic phosphor, and the liquid medium, the phosphor-containing composition may contain other optional components depending on its use. Examples of other components include a diffusing agent, a thickener, a bulking agent, and an interference agent. Specific examples include silica fine powder such as Aerosil, alumina and the like. These other components are usually contained as other components also in the second luminous body. In addition, these other components may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  In preparing the phosphor-containing composition, the Tb complex phosphor and the inorganic phosphor and the liquid medium are mixed. At this time, either the Tb complex phosphor or the inorganic phosphor is the first. It may be mixed with a liquid medium. Alternatively, a Tb complex phosphor and an inorganic phosphor may be mixed in advance to prepare a phosphor mixture, and this phosphor mixture may be mixed with a liquid medium. Further, a part of the Tb complex phosphor and the inorganic phosphor may be used as a phosphor mixture, and the other part may be mixed with the liquid medium first. When preparing the phosphor mixture, the ratio of the Tb complex phosphor and the inorganic phosphor is arbitrary, but usually the Tb complex phosphor and the inorganic phosphor to be contained in the second phosphor to be produced are prepared. Try to match the ratio. In addition, the term “mixing” as used herein does not necessarily mean that phosphors are mixed with each other, and means that different types of phosphors are combined.

Once the phosphor-containing composition is prepared, it is molded into a desired shape and cured to produce a second light emitter.
For example, when the second light-emitting body is formed in a film shape, the phosphor-containing composition may be applied to an application target such as a substrate to form a coating film. Further, for example, when the second light emitter is formed in a cup-shaped frame as in the embodiments described later, the concave portion of the frame may be filled with the phosphor-containing composition.

The curing method may be selected according to the type of the liquid medium, and for example, heat treatment, light irradiation treatment, cooling treatment, etc. may be performed. Moreover, when using the liquid medium which melt | dissolves sealing resin in a solvent, what is necessary is just to harden by drying and removing the said solvent.
In this manner, a second light emitter can be manufactured.
In addition, said fluorescent substance containing composition and fluorescent substance mixture can be widely used also for uses other than producing 2nd light-emitting bodies, such as fluorescent ink, for example.

[3. Overall configuration of light emitting device]
The light-emitting device of the present invention is not particularly limited as long as it includes the first light-emitting body and the second light-emitting body described above. Usually, the first light-emitting body is formed on an appropriate frame. And a second light emitter. At this time, the second light emitter is excited by the light emission of the first light emitter (that is, the Tb complex phosphor and the inorganic phosphor are excited) to emit light, and the light emission of the first light emitter. And / or it arrange | positions so that light emission of a 2nd light-emitting body may be taken out outside. In this case, the Tb complex phosphor and the inorganic phosphor may be uniformly dispersed in the second light emitting part, but may not be uniform.

  In the light emitting device of the present invention, members other than the first light emitter, the second light emitter, and the frame described above may be used. As an example, an adhesive portion can be mentioned. As a specific example, the bonding portion can be used in the light emitting device for bonding the first light emitting body, the second light emitting body, and the frame. In addition, as an adhesion part, it can form with the material similar to sealing resin illustrated as a constituent material of a 2nd light-emitting body, for example.

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

  FIG. 1 is a diagram schematically showing a configuration of a light emitting device according to an embodiment of the present invention. The light-emitting device 1 of the present embodiment absorbs a part of light emitted from the frame 2, a near-ultraviolet LED (first light emitter) 3 that is a light source, and the near-ultraviolet LED 3, and light having a wavelength different from that. A phosphor-containing portion (second light emitter) 4 that emits light.

  The frame 2 is a metal base for holding the near-ultraviolet LED 3 and the phosphor-containing portion 4. On the upper surface of the frame 2, a trapezoidal concave section (dent) 2A having an opening on the upper side in FIG. Thereby, since the frame 2 has a cup shape, the light emitted from the light emitting device 1 can have directivity, and the emitted light can be used effectively. Further, the inner surface of the concave portion 2A of the frame 2 is enhanced in the reflectance of light in the entire visible light region by metal plating such as silver. Can be discharged in a predetermined direction.

  Near-ultraviolet LED 3 is installed at the bottom of recess 2A of frame 2 as a first light emitter. The near-ultraviolet LED 3 is an LED that emits near-ultraviolet light when supplied with electric power. The near-ultraviolet light emitted from the near-ultraviolet LED 3 is absorbed as excitation light by the phosphor (Tb complex phosphor and inorganic phosphor) in the phosphor-containing portion 4.

  Further, the near-ultraviolet LED 3 is installed at the bottom of the recess 2A of the frame 2 as described above. Here, a silver paste (a mixture of silver particles in an adhesive) 5 is provided between the frame 2 and the near-ultraviolet LED 3. Thus, the near-ultraviolet LED 3 is installed on the frame 2. Further, the silver paste 5 also plays a role of efficiently dissipating heat generated in the near ultraviolet LED 3 to the frame 2.

  Further, a gold wire 6 for supplying power to the near ultraviolet LED 3 is attached to the frame 2. That is, an electrode (not shown) provided on the upper surface of the near-ultraviolet LED 3 is connected by wire bonding using the wire 6, and when the wire 6 is energized, power is supplied to the near-ultraviolet LED 3. The ultraviolet LED 3 emits near ultraviolet light. One or a plurality of wires 6 are attached in accordance with the structure of the near ultraviolet LED 3.

Further, the concave portion 2A of the frame 2 is provided with a phosphor-containing portion 4 that absorbs part of the light emitted from the near-ultraviolet LED 3 and emits light having a different wavelength. The phosphor-containing part 4 is formed of a phosphor and a transparent resin. In the present embodiment, a Tb complex phosphor and an inorganic phosphor are used as the phosphor. What is necessary is just to select the specific kind and ratio of Tb complex fluorescent substance and inorganic fluorescent substance so that the sum total of the light which the fluorescent substance light emission part 4 emits may become a desired color. The color is not limited to white, but may be yellow, orange, pink, purple, blue-green, or the like. Further, it may be an intermediate color between these colors and white. Here, as a phosphor, a Tb complex phosphor that emits green light, an inorganic phosphor that emits red light (red inorganic phosphor), and an inorganic phosphor that emits blue light (blue inorganic phosphor) are used. It is assumed that light is emitted.
Moreover, transparent resin is sealing resin of the fluorescent substance containing part 4, and uses the above-mentioned sealing resin here.

  The mold unit 7 functions as a lens for protecting the near-ultraviolet LED 3, the phosphor-containing unit 4, the wire 6, and the like from the outside and controlling the light distribution characteristics. An epoxy resin can be mainly used for the mold part 7. Moreover, the fluorescent substance containing part 4 may take a means for sealing the fluorescent substance in a vacuum.

  Since the light emitting device of the present embodiment is configured as described above, when the near-ultraviolet LED 3 emits light, the Tb complex phosphor, the red inorganic phosphor, and the blue inorganic phosphor in the phosphor light emitting unit 4 are excited, Each emits green, red and blue light. As a result, white light is emitted from the light emitting device as combined light composed of green, red, and blue light.

The light-emitting device of the present invention is not limited to the above-described embodiment, and can be implemented with any changes without departing from the gist thereof.
For example, a surface-emitting type can be used as the first light emitter, and a film-like one can be used as the second light emitter. In this case, it is preferable to have a shape in which the film-shaped second light emitter is in direct contact with the light emitting surface of the first light emitter. In addition, contact here means producing the state which the 1st light-emitting body and the 2nd light-emitting body have touched exactly without passing air or gas. As a result, it is possible to avoid a light amount loss in which light from the first light emitter is reflected by the film surface of the second light emitter and oozes out, so that the light emission efficiency of the entire apparatus can be improved.

FIG. 2 is a schematic perspective view showing an example of a light emitting device in which a surface light emitting type is used as the first light emitter and a film-like one is applied as the second light emitter. In the light-emitting device 8 shown in FIG. 2, a surface-emitting GaN-based LD 10 as a first light-emitting body is provided on a substrate 9, and a film-shaped second light-emitting body 11 is formed on the surface-emitting GaN-based LD 10. Has been. Here, in order to create a state where they are in contact with each other, the LD 10 as the first light emitter and the second light emitter 11 are prepared separately, and their surfaces are brought into contact with each other by an adhesive or other means. Alternatively, the second light emitter 11 may be formed (molded) on the light emitting surface of the LD 10. As a result, the LD 11 and the second light emitter 11 can be brought into contact with each other.
According to the light-emitting device 8 having such a configuration, in addition to the same advantages as those of the above-described embodiment, it is possible to improve the light emission efficiency by avoiding the loss of light amount.

[5. Advantages of light-emitting device of the present invention]
Although the light-emitting device of the present invention uses a complex phosphor containing Tb, it is possible to provide a light-emitting device having a large total luminous flux by using a high-brightness specific Tb complex phosphor together with an inorganic phosphor. it can. Specifically, it is usually 0.01 lumen or more, preferably 0.05 lumen or more, more preferably 0.1 lumen or more. The upper limit is not limited, but it is usually 10 lumens or less. The total luminous flux can be measured by, for example, a fiber multichannel spectrometer (USB 2000 manufactured by Ocean Optics).

  As described above, when the Tb complex phosphor and the inorganic phosphor are used in combination, the reason why a higher luminance than that obtained when the Tb complex and the organic complex phosphor are used in combination is not clear. It is guessed as follows. That is, when a light-emitting device is produced by combining a Tb complex phosphor and an organic complex phosphor, it is considered that the Tb complex phosphor partially dissolves when the sealing resin is cured. Therefore, when the Tb complex phosphor is mixed with the organic complex phosphor, the Tb complex phosphor undergoes ligand exchange with the organic complex phosphor, the cluster structure of the Tb complex phosphor is destroyed, and the luminance of the light emitting device is greatly reduced. It is presumed that it was. On the other hand, when the Tb complex phosphor is mixed with an inorganic phosphor, the above-described ligand exchange does not occur, and thus it is considered that high-luminance emission can be maintained without breaking the cluster structure of the Tb complex phosphor. .

[6. Application of light emitting device]
The application of the light-emitting device of the present invention is not particularly limited, and can be used in various fields where a normal light-emitting device is used. Among these, when used together with a color filter, the color reproducibility range is widened. Therefore, the light emitting device of the present invention is particularly preferably used as a light source of an image display device and an illumination device. In addition, when using the light-emitting device of this invention as a light source of an image display apparatus, using with a color filter is preferable. For example, when the image display device is a color image display device using a color liquid crystal display element, the light emitting device is used as a backlight, an optical shutter using liquid crystal, and a color filter having red, green, and blue pixels. By combining these, an image display device can be formed.

  An example of a surface emitting illumination device 12 incorporating the light emitting device 1 is schematically shown in FIG. In the surface light emitting illumination device 12, a large number of light emitting devices 1 are provided on the bottom surface of a rectangular holding case 13 whose inner surface is light-opaque such as a white smooth surface, and a power source for driving the light emitting device 1 is provided on the outside thereof. And a circuit or the like (not shown). In order to make the light emission uniform, a diffuser plate 14 such as a milky white acrylic plate is fixed to a portion corresponding to the lid portion of the holding case 13.

  When the surface emitting illumination device 12 is used, the light emitting device 1 emits light. This light is transmitted through the diffusion plate 14 and emitted upward in the drawing, and illumination light with uniform brightness can be obtained within the surface of the diffusion plate 14 of the holding case 13.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to a following example, unless it deviates from the summary.

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

[Emission color evaluation method]
The semiconductor light emitting devices produced in the examples and comparative examples were caused to emit light, and the emitted light was measured with a fiber multichannel spectrometer (USB2000 manufactured by Ocean Optics), and the xyz chromaticity coordinates of the emitted light were determined.

[Measurement method of total luminous flux]
The semiconductor light emitting devices produced in the examples and comparative examples were allowed to emit light, and the emitted light was measured with a fiber multichannel spectrometer (USB 2000 manufactured by Ocean Optics), and the total luminous flux (lumen) of the emitted light was determined. .

[Measurement method of radiant flux]
The semiconductor light-emitting devices produced in the examples and comparative examples were allowed to emit light, and the emitted light was measured with a fiber multichannel spectrometer (USB 2000 manufactured by Ocean Optics) to determine the radiant flux (microwatt) of the emitted light. It was.

[Measurement method of emission spectrum]
The semiconductor light emitting devices produced in the examples and comparative examples were caused to emit light, and the emission spectrum of the emitted light was measured with a fiber multichannel spectrometer (USB 2000 manufactured by Ocean Optics).

[Example 1]
Red phosphor (Sr, Ca) AlSiN ₃ : Eu, green phosphor hexyl salicylate-Tb (III) nine-nuclear complex (Tb complex phosphor), and blue phosphor BaAlMn ₁₀ O ₁₇ : Eu Were mixed at a weight ratio of 3:66:31 to prepare a phosphor mixture. Note that the phosphor used as a raw material is in powder form.

  125 mg of the obtained phosphor mixture and 500 mg of an inorganic material (the production method will be described later) are mixed, and the defoaming process is performed for 1 minute and the mixing process is performed for 3 minutes with the centrifugal defoamer “Awatori Rentaro AR100”. And a phosphor-containing composition was prepared.

  As shown in FIG. 5, a light emitting device (emission peak wavelength 395 nm) [100] in which a GaN-based semiconductor light emitting element (manufactured by Cree, 395 MB) [103] is installed at the bottom [102] of a polyphthalamide cup [101]. In the concave part [104] of the cup [101], the obtained phosphor-containing composition was dropped twice with a micropipette, and a total of 3.5 μl was dropped, and heated at 120 ° C. for 1 hour for the first drying. Went. Subsequently, heating was performed at 150 ° C. for 3 hours and second drying was performed. As a result, a phosphor layer [106] having no defects, in which the phosphor [105] was uniformly dispersed, could be formed. In the light emitting device [100], an electrode (not shown) provided on the cup [101] and the light emitting element [103] are connected by a wire [107], and power is supplied through the wire [107], thereby the light emitting element. [103] emits light. In the description of the embodiment, the numerical value in parentheses “[]” is a symbol indicating the corresponding part in FIG.

The semiconductor light-emitting device thus obtained was driven at 20 mA, and its emission color, luminance, emission intensity, and emission spectrum were measured by the method described above. The results of emission color, luminance, and emission intensity are shown in Table 1 as Tb-1. FIG. 6 shows an emission spectrum.
Further, by the same operation, a semiconductor light emitting device was produced four more times, and its total luminous flux, radiant flux, and chromaticity coordinates were measured by the method described above. These measurement results are shown in Table 1 as Tb-2 to Tb-5.

In addition, the inorganic material mentioned above is synthesize | combined as follows. 1400 g of GE Toshiba Silicone double-ended silanol dimethyl silicone oil XC96-723, 140 g of phenyltrimethoxysilane, and 3.08 g of zirconium tetraacetylacetonate powder as a catalyst were prepared. The mixture was weighed into a mouth-opening colben and stirred at room temperature for 15 minutes until the catalyst was sufficiently dissolved. Thereafter, the temperature of the reaction solution was raised to 120 ° C., and initial hydrolysis was performed while stirring at 120 ° C. under total reflux for 30 minutes.
Subsequently, nitrogen was blown in with SV20 and stirred at 120 ° C. while distilling off the generated methanol, moisture and by-product low boiling silicon components, and the polymerization reaction was further advanced for 6 hours. Here, “SV” is an abbreviation for “Space Velocity” and refers to the volume of blown volume per unit time. Therefore, SV20 refers to blowing N ₂ in a volume 20 times that of the reaction solution in one hour.
After stopping the blowing of nitrogen and cooling the reaction solution to room temperature, the reaction solution was transferred to an eggplant-shaped flask, and methanol and moisture remaining in a minute amount at 120 ° C. and 1 KPa on an oil bath using a rotary evaporator, The low boiling silicon component was distilled off to obtain a solventless inorganic material.

[Comparative Example 1]
The red phosphor Eu (Hexafluoroacetylatenate) ₃ (Triphenylphosphineoxide) ₃ , the green phosphor hexyl salicylate-Tb (III) nine-nuclear complex, and the blue phosphor BaAlMn ₁₀ O ₁₇ : Eu 2:65: A phosphor mixture was prepared by mixing at a weight ratio of 33. Note that the phosphor used as a raw material is in powder form.

Using this phosphor mixture, a phosphor-containing composition was prepared in the same manner as in Example 1, and the phosphor layer [106] was formed on the fermentation device [100].
The semiconductor light-emitting device thus obtained was driven at 20 mA, and its emission color, luminance, emission intensity, and emission spectrum were measured by the method described above. The results of emission color, luminance, and emission intensity are shown in Table 1 as -1 after Tb-Eu curing. FIG. 7 shows an emission spectrum.
Further, by the same operation, a semiconductor light emitting device was produced three more times, and the total luminous flux, radiant flux, and chromaticity coordinates were measured by the method described above. These measurement results are shown in Table 1 as −2 after Tb-Eu curing and −4 after Tb-Eu curing.

[Summary 1]
Both Example 1 and Comparative Example 1 give different results for each operation, but these are considered to be within the error range.
The light-emitting device of the present invention produced by combining a Tb complex phosphor and an inorganic phosphor from Example 1 and Comparative Example 1 rather than a light-emitting device produced by combining a Tb complex phosphor and an organic phosphor. However, it was confirmed that light was emitted with high luminance.

[Example 2]
An equimolar amount of triethylamine (0.270 g, 2.70 mmol) was added to 50 ml of a methanolic solution of hydroxyethyl salicylate (0.492 g, 2.70 mmol), stirred at room temperature for a predetermined time, and then Tb (NO ₃ ) ₃ · 6H. 10 ml of a methanol solution of ₂ O (0.690 g, 1.52 mmol) was added dropwise and stirred at 40 ° C. for 2 hours. The obtained transparent solution was filtered and allowed to stand to obtain white crystals. The crystals were washed several times with cold methanol, filtered and air-dried to obtain hydroxyethyl salicylate-Tb nine-nuclear complex. A light emitting device was prepared and evaluated in the same manner as in Example 1 except that the type of the nine-nucleus complex used was changed. The results are shown in Table 2.

[Example 3]
An equimolar amount of triethylamine (0.270 g, 2.70 mmol) was added to 50 ml of a methanol solution of ethylhexyl salicylate (0.676 g, 2.70 mmol), stirred at room temperature for a predetermined time, and then Tb (NO ₃ ) ₃ · 6H _2. 10 ml of a methanol solution of O (0.690 g, 1.52 mmol) was added dropwise and stirred at 40 ° C. for 2 hours. The obtained transparent solution was filtered and allowed to stand to obtain white crystals. The crystals were washed several times with cold methanol, filtered and air-dried to obtain ethylhexyl salicylate-Tb non-nuclear complex. A light emitting device was prepared and evaluated in the same manner as in Example 1 except that the type of the nine-nucleus complex used was changed. The results are shown in Table 2.

[Example 4]
An equimolar amount of triethylamine (0.270 g, 2.70 mmol) was added to 50 ml of a methanolic solution of methyl salicylate (0.411 g, 2.70 mmol), stirred at room temperature for a predetermined time, and then Tb (NO ₃ ) ₃ · 6H _2. 10 ml of a methanol solution of O (0.690 g, 1.52 mmol) was added dropwise and stirred at 40 ° C. for 2 hours. The obtained white crystals were washed several times with cold methanol, filtered, and air-dried to obtain methyl salicylate-Tb nine-nuclear complex. A light emitting device was prepared and evaluated in the same manner as in Example 1 except that the type of the nine-nucleus complex used was changed. The results are shown in Table 2.

[Summary 2]
In any of Examples 2 to 4, different results were obtained for each operation, but these are considered to be within the error range.
From Examples 1 to 4, it was confirmed that light was emitted with high luminance regardless of the type of ligand L included in the Tb complex phosphor.

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

It is a figure which shows typically the structure of the light-emitting device which concerns on one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view showing an embodiment of the present invention, showing an example of a light-emitting device using a surface-emitting type as a first light emitter and a film-like one as a second light emitter. is there. BRIEF DESCRIPTION OF THE DRAWINGS It is shown about one Embodiment of this invention, and is a figure which shows typically an example of the surface emitting illumination device incorporating the light-emitting device. It is a figure for demonstrating an example of preferable specific Tb fluorescent substance, Comprising: It is a typical conceptual diagram of the molecular structure in case specific Tb fluorescent substance is a nine-nuclear rare earth polynuclear complex. It is sectional drawing which shows typically the light emitting device produced in the Example and comparative example of this invention. It is a figure showing the emission spectrum measured in Example 1 of this invention. 6 is a diagram showing an emission spectrum measured in Comparative Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 Frame 2A The recessed part of a flame | frame 3 Near ultraviolet LED (1st light-emitting body)
4 Phosphor-containing part (second light emitter)
5 Silver paste 6 Wire 7 Mold part 8 Light-emitting device 9 Substrate 10 Surface-emitting GaN-based LD (first light emitter)
DESCRIPTION OF SYMBOLS 11 2nd light-emitting body 12 Surface emitting illuminating device 13 Holding case 14 Diffusion plate 100 Light emitting device 101 Polyphthalamide cup 102 Bottom part 103 GaN-type semiconductor light-emitting device 104 Recessed part 105 Phosphor 106 Phosphor layer 107 Wire

Claims (6)

A light emitting device comprising: a first light emitter; and a second light emitter that emits visible light by irradiation of light from the first light emitter,
The light emitting device, wherein the second light emitter contains a complex phosphor containing Tb and an inorganic phosphor. The light emitting device according to claim 1, wherein the second light emitter contains two or more of the inorganic phosphors. The complex phosphor has an emission peak in a wavelength range of 510 nm to 560 nm;
3. The light emitting device according to claim 1, wherein at least one of the inorganic phosphors has a light emission peak in a wavelength range of 570 nm to 700 nm or a wavelength range of 420 nm to 480 nm. The light emitting device according to claim 1, wherein the complex phosphor is represented by the following formula (I).
L _a (Ln) _b X _c (I)
{In Formula (I),
L represents a ligand represented by the formula (II),

(In Formula (II), R ^{1 to} R ⁵ each independently represents a hydrogen atom or a monovalent substituent, Y ¹ represents —OH, and Y ² represents ═O.)
Ln each independently represents a rare earth ion, and at least one of Ln represents a terbium ion,
X represents an anion,
a, b and c represent integers satisfying 1 ≦ a / b ≦ 4 and 1 <c / b ≦ 4.
Y ¹ and Y ² are coordinated to the same or different Ln. } An image display device comprising the light-emitting device according to claim 1 as a light source. An illuminating device comprising the light-emitting device according to claim 1 as a light source.

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