JP4513287B2 - Light emitting device, lighting device, and image display device - Google Patents

Description

  The present invention relates to a light-emitting device, and more specifically, a first light emitter that emits light from ultraviolet light to visible light region by a power source, and absorbs light in the visible light region from the ultraviolet light to generate long-wavelength visible light. By combining with a second phosphor as a wavelength conversion material having a phosphor containing a phosphor containing a luminescent center ion as a base compound that emits light, color rendering is good regardless of the usage environment and high intensity light emission is generated. The present invention relates to a light-emitting device that can be used.

In order to generate white and other various colors uniformly and with good color rendering by mixing blue, red, and green, a light emitting device in which the light emission color of an LED or LD is converted with a phosphor has been proposed. For example, in JP-B-49-1221, phosphor a beam of laser emitting a radiation beam having a wavelength of _{300-530nm (Y 3-xy Ce x} Gd y M 5-z Ga z O 12 (Y is Y, Lu , Or La, M represents Al, Al—In, or Al—Sc))), and this is emitted to form a display. Further, in recent years, a white light emitting device configured by combining a gallium nitride (GaN) LED or LD with high luminous efficiency, which has been attracting attention as a blue light emitting semiconductor light emitting element, and a phosphor as a wavelength conversion material. However, it has been proposed as a light-emitting source for an image display device and a lighting device, taking advantage of the feature of low power consumption and long life. Actually, Japanese Patent Application Laid-Open No. 10-242513 discloses a light emitting device using this nitride semiconductor LED or LD chip and using yttrium, aluminum, garnet as a phosphor. . In U.S. Patent No. 6,278,135, the light-emitting device that emits visible light by receiving ultraviolet light of the phosphor from the LED, BaMg ₂ Al ₁₆ O ₂₇ as its phosphor: Eu ²⁺ Hitoshiga示Has been. W
In O00 / 033389, in a light emitting device in which a phosphor receives light from a blue LED and emits visible light, (Sr, Ca, Ba) (Al, Ga) ₂ is used as a phosphor emitting green light around 540 nm. S ₄ : Eu ^{2+ and the} like are shown.

However, so far, the first illuminant such as an LED or the like emits light such as a combination of an yttrium / aluminum / garnet phosphor as disclosed in JP-A-10-242513 as the second illuminant. The apparatus does not satisfy both the light emission intensity and the color rendering properties, and further improvement is required as a light source such as a display, a backlight light source, and a traffic light. Further, BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ or (Sr, which is described as a material for converting LED light into blue visible light or green visible light as disclosed in US Pat. No. 6,278,135. The same applies to Ca, Ba) (Al, Ga) ₂ S ₄ : Eu ²⁺ , and it is required to further improve both the color rendering properties and the emission intensity. Note that color rendering is one of the factors that are problematic when white light is generated by mixing blue, green, and red phosphors. This is a scale that indicates how close the color of an object illuminated with light emitted from a phosphor is. Normally, blue, green, and red phosphors are mixed to produce white light, but the known blue phosphor and green phosphor that can be used to obtain white light have peaks around 450 nm and 540 nm, respectively. Since there is a large valley between the blue and green emission peaks with the top, the spectrum of white light by the combination of blue, green and red becomes a valley in the 460-520 nm region, and there is no valley in that region. This cannot be matched with the sunlight spectrum, and this is one of the causes of low color rendering of white light of the blue, green and red mixed phosphors.
Japanese Patent Publication No.49-1221 Japanese Patent Laid-Open No. 10-242513 US Pat. No. 6,278,135 WO00 / 033389

  The present invention has been made in view of the above-mentioned prior art, and has been made to develop a light emitting device having high color rendering properties and high emission intensity. Therefore, the present invention is easy to manufacture and has color rendering properties. An object of the present invention is to provide a double light-emitting type light emitting device having high emission intensity.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have used a phosphor that emits an intermediate color between blue and green in order to improve the color rendering of white light. It is important to compensate for this, and a system that combines [blue phosphor] + [green phosphor] + [red phosphor] + [phosphor that emits strong blue-green light], [blue and green areas approaching blue Combination of [phosphor that emits strongly in the green region] + [red phosphor], combination of [blue phosphor] + [phosphor that emits strongly in the blue-green region by reaching the green region] + [red phosphor] It has been found that a system combining [phosphor that emits strong light in the blue-green region by approaching the blue region] + [green phosphor] + [red phosphor] gives white light with high color rendering properties. In the light emitting device including the first light emitter that generates light of 350 to 415 nm and the second light emitter that generates visible light by irradiation with light from the first light emitter, the second light emission is performed. When a phosphor containing a crystal phase having the following specific chemical composition is used as the body, the phosphor emits strong blue-green light, and the phosphor is irradiated with light in the vicinity of 350 to 415 nm, and is visible with good color rendering and high intensity. As a result of light emission, the above object was achieved. Specifically, by using a perovskite or a perovskite-like crystal composed of a monovalent metal and a divalent metal halide activated by Eu ²⁺ , strong light emission in the 460-520 nm region by excitation of light near 400 nm. The emission intensity of the light-emitting element is known blue phosphor BaMgAl ₁₀ O ₁₇ : Eu ²⁺ or green phosphor (Sr, Ca, Ba) (Al, which emits light by excitation near 400 nm. Ga) ₂ S ₄ : It is equivalent to or stronger than Eu ²⁺ and its half-width of its strong emission peak is very large, so it is good as a blue or green phosphor, and both color rendering properties and luminance are good. The inventors have found that a good light emitting device can be provided, and have reached the present invention.

That is, the present invention is directed to a phosphor having a crystal phase having a chemical composition represented by the following general formula [1] and its gist.

(In the above general formula [1], A is Cs, M is Mg, Ca, a divalent metal element selected from Sr, X table but a halogen element, or 70 mol% is F, a is a number satisfying 0.01 ≦ a ≦ 0.25 .)
Another gist is a light emitting device having a first light emitter that generates light of 350 to 415 nm and a second light emitter that generates visible light by irradiation of light from the first light emitter. The gist of the light-emitting device is characterized in that the second light-emitting body contains the phosphor.

  According to the present invention, it is possible to provide a light emitting device having high color rendering properties and high emission intensity.

The present invention is a light-emitting device in which a first light-emitting body that emits light of 350 to 415 nm and a second light-emitting body that is a phosphor are combined, and the second light-emitting body is represented by the following general formula [1]. It contains a phosphor having a crystal phase having a chemical composition.

(In the above general formula [1], A represents a monovalent metal element, M represents a divalent metal element other than Eu, X represents a halogen element, Z represents a monovalent, divalent, trivalent, It represents at least one element selected from the group consisting of tetravalent, pentavalent, hexavalent, −1 valent, −2 valent, and −3 valent elements, where a is 0.0001 ≦ a ≦ 1, b. Is a number satisfying 0 ≦ b ≦ 0.1.)
The metal element A in the formula [1] is a monovalent metal element, and examples thereof include alkali metal elements, Au, Ag, Cu, etc., and alkali metals among A from the viewpoint of color rendering properties and light emission intensity. The element preferably occupies 70 mol% or more, more preferably the sum of Cs, Rb, and K occupies 70 mol% or more, more preferably Cs occupies 50 mol% or more, and A particularly comprises Cs. preferable.

  The metal element M in the formula [1] is a divalent metal element other than Eu, and examples thereof include Mg, Ca, Sr, Ba, Zn, Mn, Pb, Cd, and Sn. In view of the above, it is preferable that the total of Mg, Ca, Sr, Ba, Zn, and Mn occupies 70 mol% or more in M, and M is a group consisting of Mg, Ca, Sr, Ba, Zn, and Mn. More preferably, it is composed of at least one element selected from the above, and the ratio of Mg in M is 50 mol% or more.

The Eu molar ratio a in the general formula [1] is 0.0001 ≦ a ≦ 1, but in terms of color rendering properties and light emission intensity, the lower limit is 0.01 or more. Preferably, it is 0.015 or more, and speaking about the upper limit, it is preferably 0.6 or less, and more preferably 0.25 or less. If the content of the luminescent center ion Eu ²⁺ is less than the above range, the emission intensity tends to be small. On the other hand, if the content exceeds the above range, the emission intensity also tends to decrease due to a phenomenon called concentration quenching.

  X in the formula [1] is preferably a halogen element. From the viewpoints of color rendering properties and emission intensity, it is more preferable that F occupies 70 mol% or more in X, and X further comprises F. preferable.

  Z in the formula [1] represents an impurity or excess M, A, or X, a monovalent element that is the valence of A, a divalent element that is the valence of M, and In addition to the -1 valent element that is the valence of X, a trivalent, tetravalent, pentavalent, hexavalent, -2 valent, and -3 valent element may be used. May promote the diffusion of the main elements in the solid and may help to crystallize the perovskite-like crystals, and even if some cation deficiency or anion deficiency occurs due to the heterovalent element, there is no significant effect on the fluorescence performance for this purpose. Because of that. As specific examples, Li, Na, K, Rb, Cs, Sc, Y, Zr, B, Al, Sc, Y, Ti, V, Cr, Zr, Nb, Hf, Ta, Bi, Sr, Ba, Ca, Examples of elements include Mg, Mn, Zn, Sm, Pb, Sn, Cl, F, Br, I, P, Sb, Tm, Ce, O, H, Si, and N. Absent. The molar ratio of Z may be included as long as there is little influence on the fluorescence performance, and it may be equal to or less than the molar ratio corresponding to the impurity level to total element ratio of 2% and b ≦ 0.1. . From the viewpoint of the performance of the phosphor, b ≦ 0.01 is preferable, and b = 0 is more preferable.

For example, in the case of _{Cs 1.01 Ca 0.3 Mg 0.5 Eu 0.2} F 3 (OH) 0.01, A is a metal element Cs, M is a metal element group consisting of Ca and Mg, because OH is an impurity, AM _0.8 E
Since it is expressed as u _0.2 F ₃ Z _0.03 and a and b satisfy the above inequality, Cs _1.01 Ca _0.3 Mg _0.5 Eu _0.2 F ₃ (OH) _0.01 falls within the category of the above-mentioned formula [1].

  The phosphor used in the present invention is excited by light of 350 to 415 nm from the first light emitter, and generates visible light. The phosphor has a good color rendering property upon excitation of light of 350 to 415 nm, generates visible light having a strong emission intensity, has a high color rendering property and a high luminance by 400 nm excitation light emitted from a GaN-based semiconductor. It is found that emits.

The crystal structure of the phosphor in the present invention is ^{_{M I + M II 2+ X I}} - perovskite structure and it distorted structure represented by ₃ (where, M _I is a monovalent element, M _II is a divalent element X _I is mainly halogen). In these perovskite crystals or perovskite-like crystals, crystal systems such as tetragonal crystals, orthorhombic crystals, and trigonal crystals can be taken in addition to cubic crystals. These can be obtained by introducing various sizes of elements into the M _I and M _II sites. As examples of a cubic perovskite structure and a trigonal perovskite-like structure, FIGS. 1 and 2 show X-ray diffraction patterns of CsCaF ₃ and Cs ₂ NaCrF ₆ , respectively (from the powder X-ray diffraction database). In the present invention, CsCaF ₃ activated with a small amount of Eu becomes a cubic perovskite. When this Cs site or Ca site is substituted with another monovalent element or divalent element having a different cation radius, Further, the brightness tends to be higher. The crystal system at this time tends to change to a crystal system other than cubic such as trigonal. Therefore, in the present invention, the crystal system has an M _I site or M _II site composed of a plurality of elements having different cation radii or activated with a metal element constituting the M _II site due to deviation from the cubic crystal. When the cation radius of the agent Eu is different, it is more preferable to sufficiently increase the substitution molar ratio of Eu.

The phosphor used in the present invention includes compounds of A source, M source, X source, Z source and element source compound of luminescent center ion (Eu) as shown in the general formula [1] below ( The mixture prepared by the mixing method of A) or (B) can be produced by heat treatment and baking. (A) A dry pulverizer such as a hammer mill, a roll mill, a ball mill or a jet mill, or a pulverizer using a mortar and pestle, a mixer such as a ribbon blender, V-type blender or Henschel mixer, or a mortar and pestle. Dry mixing method combined with the mixture used.
(B) Using a pulverizer or a mortar and pestle, etc., add water etc. and mix in a slurry or solution state with a pulverizer, mortar and pestle, or evaporating dish and stirrer, spray drying, heating Wet mixing method that is dried by drying or natural drying.

  Among these mixing methods, in particular, in the element source compound of the luminescent center ion, it is preferable to use a liquid medium because a small amount of compound needs to be mixed and dispersed uniformly throughout, and other elements are also used. The latter wet method is also preferred from the viewpoint of obtaining uniform mixing throughout the source compound, and the heat treatment method is usually 500 to 1500 ° C. in a heat-resistant container such as a crucible or tray made of alumina or quartz, The heating is preferably performed at a temperature of 600 to 1300 ° C. for 10 minutes to 50 hours in a single or mixed atmosphere of a gas such as air, oxygen, carbon monoxide, carbon dioxide, nitrogen, hydrogen, and argon. In addition, after heat processing, washing | cleaning, drying, a classification process, etc. are made | formed as needed.

  As the heating atmosphere, an atmosphere necessary for obtaining an ion state (valence) in which the element of the emission center ion contributes to light emission is selected. In the case of divalent Eu or the like in the present invention, a neutral or reducing atmosphere such as carbon monoxide, nitrogen, hydrogen, and argon is preferable, but it can be selected even under an oxidizing atmosphere such as air and oxygen. .

Here, as the compounds of the A source, M source, and Eu source, halides of A, M, and Eu are mainly preferred. When using NH ₄ X, HX, etc. as the X source compound, it is desirable to use oxides, hydroxides, carbonates, nitrates, oxalates, carboxylates, etc. of A, M, and Eu, Even when NH ₄ X, HX, or the like is not used, it is possible to use a part of them for synthesis. Examples of the X source compound include AX, MX ₂ , EuX ₃ , NH ₄ X, and HX. Of these, the chemical composition, reactivity, and non-generation of NO _x , SO _x, etc. during firing are selected.

Specific examples of the compound Cs, Rb, or K as a raw material for synthesis that are preferable as the metal element A are given. The Cs source compound mainly includes CsX, that is, CsF, CsCl, CsBr, etc., but in combination with other halides, CsOH, Cs ₂ CO ₃ , CsNO ₃
, CsOCOCH _{3 and the} like.

Rb source compounds mainly include RbX, that is, RbF, RbCl, RbBr, etc., but in combination with other halides, RbOH.nH ₂ O, Rb ₂ CO ₃ , RbN
Examples include O ₃ and RbOCOCH ₃ .

Examples of the K source compound mainly include KX, that is, KF, KCl, KBr, and the like, and in combination with other halides, KOH, K ₂ CO ₃ , KNO ₃ , KOCOCH _{3 and the} like can be mentioned.

Specific examples of a compound for a raw material of synthesis of the element Ba, Mg, Ca, Zn, Mn, or Sr that are preferable as the metal element M are mainly BaX ₂ , that is, BaF ₂ , BaCl ₂ , BaBr. ₂ · 2H ₂ O and the like, and in combination with other halides, BaO, Ba (OH) ₂ · 8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , Ba (OCOCH ₃ ) _{2 and the} like are mentioned. It is done.

Mg source compounds are mainly MgX ₂ , that is, MgF ₂ , MgCl ₂ , MgBr ₂ .6H ₂ O.
In combination with other halides, MgO, Mg (OH) ₂ ,
MgCO ₃ , Mg (OH) ₂ .3MgCO ₃ .3H ₂ O, Mg (NO ₃ ) ₂ .6H ₂ O, Mg (
OCOCH _{3) 2} · 4H ₂ O, and the like.

The Ca source compound, primarily CaX ₂ That _{CaF 2, CaCl 2, CaBr 2} · 2H 2 but O, and the like, CaO in combination with other halides, Ca (OH) _2, C
Examples include aCO ₃ , Ca (NO ₃ ) ₂ .4H ₂ O, Ca (OCOCH ₃ ) ₂ .H ₂ O, and the like.

The Zn source compound is mainly ZnX ₂ , that is, ZnF ₂ .4H ₂ O, ZnCl ₂ , ZnBr _2.
ZnO, Zn (OH) ₂ in combination with other halides, etc.
ZnCO ₃ , Zn (NO ₃ ) ₂ .6H ₂ O, Zn (OCOCH ₃ ) ₂ , ZnCl _{2 and the} like can be mentioned.

As the Mn source compound, mainly MnX ₂ , that is, MnF ₂ , MnCl ₂ .4H ₂ O, MnBr ₂
· 4H ₂ but O, and the like, MnO _2, Mn ₂ in combination with other halides
O ₃ , Mn ₃ O ₄ , MnO, Mn (OH) ₂ , MnCO ₃ , Mn (NO ₃ ) ₂ , Mn (OCOC)
H ₃ ) ₂ · 2H ₂ O, Mn (OCOCH ₃ ) ₃ · nH ₂ O, MnCl ₂ · 4H ₂ O and the like.

Sr source compounds are mainly SrX ₂ , that is, SrF ₂ , SrCl ₂ , SrBr ₂ .6H ₂ O.
In combination with other halides, SrO, Sr (OH) _2.
Examples thereof include 8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , Sr (OCOCH ₃ ) ₂ .0.5H ₂ O, and the like.

Furthermore, the element source compound is specifically illustrated about Eu which is an element of a luminescent center ion. EuF ₃ , EuCl ₃ .6H ₂ O, EuBr _{3 and the} like are mainly mentioned, but in combination with other halides, Eu ₂ O ₃ , Eu (NO ₃ ) ₃ .6H ₂ O, Eu (OCOCH ₃ ) ₃・
4H ₂ O and the like can be mentioned.

In the present invention, the first light emitter that irradiates the phosphor with light generates light having a wavelength of 350 to 415 nm. Preferably, a light emitter that generates light having a peak wavelength in the wavelength range of 350 to 415 nm is used. Specific examples of the first light emitter include a light emitting diode (LED) or a laser diode (LD). Laser diodes are preferred because they consume less power. Of these, GaN LEDs and LDs using GaN compound semiconductors are preferred. This is because GaN-based LEDs and LDs have significantly higher light emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely bright with very low power when combined with the phosphor. This is because light emission can be obtained. For example, for a current load of 20 mA, the GaN system usually has a light emission intensity 100 times or more that of the SiC system. GaN-based LEDs and LDs preferably have an Al _x Ga _Y N light emitting layer, a GaN light emitting layer, or an In _x Ga _Y N light emitting layer. Among GaN-based LEDs, In _X
Those having a Ga _Y N light-emitting layer are particularly preferred because the light emission intensity is very strong.
In particular, a multi-quantum well structure composed of an In _x Ga _y N layer and a GaN layer is particularly preferable because the emission intensity is very high. In the above, the value of X + Y is usually a value in the range of 0.8 to 1.2. In the GaN-based LED, those in which the light emitting layer is doped with Zn or Si or those without a dopant are preferable for adjusting the light emission characteristics. A GaN-based LED has these light-emitting layer, p-layer, n-layer, electrode, and substrate as basic constituent elements. The light-emitting layer is made of n-type and p-type Al _x Ga _y N layers, GaN layers, or In _x. Ga _Y N layer high emission efficiency which has a hetero structure in which a sandwich like, preferably, there is further higher emission efficiency which was further heterostructure quantum well structure is more preferable.

  In the present invention, it is particularly preferable to use a surface-emitting type illuminant, particularly a surface-emitting GaN-based laser diode, as the first illuminant because the luminous efficiency of the entire light-emitting device is increased. A surface-emitting type illuminant is an illuminant that emits strong light in the surface direction of a film. In a surface-emitting GaN-based laser diode, the crystal growth of a light-emitting layer or the like is controlled, and a reflective layer or the like is successfully performed. By devising, the light emission in the surface direction can be made stronger than the edge direction of the light emitting layer. When the surface emitting type is used, the light emission cross-sectional area per unit light emission amount can be increased compared to the type that emits light from the edge of the light emitting layer. As a result, the phosphor of the second light emitter is irradiated with the light. Since the irradiation area can be made very large with the same amount of light and the irradiation efficiency can be improved, stronger light emission can be obtained from the phosphor that is the second light emitter.

  When a surface-emitting type is used as the first light emitter, the second light emitter is preferably a film. As a result, the cross-sectional area of the light from the surface-emitting light emitter is sufficiently large. Therefore, when the second light emitter is formed into a film in the direction of the cross section, the irradiation cross-section area of the phosphor from the first light emitter is irradiated. Becomes larger per unit amount of phosphor, so that the intensity of light emitted from the phosphor can be further increased.

  Further, when a surface-emitting type is used as the first light emitter and a film-like one is used as the second light emitter, the second light emitter directly in the form of a film on the light-emitting surface of the first light emitter. It is preferable that the shape is made to contact. Contact here means to create a state in which the first light emitter and the second light emitter are in perfect contact with each other without 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. 3 is a schematic perspective view showing the positional relationship between the first light emitter and the second light emitter in an example of the light emitting device of the present invention. In FIG. 3, 1 is a film-like second light emitter having the phosphor, 2 is a surface-emitting GaN-based LD as a first light emitter, and 3 is a substrate. In order to create a state in which they are in contact with each other, the LD 2 and the second light emitter 1 may be formed separately and the surfaces may be brought into contact with each other by an adhesive or other means, or the light emitting surface of the LD 2 A second light-emitting body may be formed (molded) on the top. As a result, the LD 2 and the second light emitter 1 can be brought into contact with each other.

  The light from the first illuminant and the light from the second illuminant are usually directed in all directions. However, when the phosphor powder of the second illuminant is dispersed in the resin, the light is out of the resin. A part of the light is reflected when exiting, so the direction of the light can be adjusted to some extent. Accordingly, since light can be guided to a certain degree in an efficient direction, it is preferable to use a phosphor in which the phosphor powder is dispersed in a resin as the second luminous body. Further, when the phosphor is dispersed in the resin, the total irradiation area of the light from the first light emitter to the second light emitter is increased, so that the light emission intensity from the second light emitter can be increased. It also has the advantage of being able to. Examples of resins that can be used in this case include silicon resins, epoxy resins, polyvinyl resins, polyethylene resins, polypropylene resins, polyester resins, and the like, but the dispersibility and stability of the phosphor powder are good. In this respect, silicon resin or epoxy resin is preferable. When the powder of the second luminous body is dispersed in the resin, the weight ratio of the powder of the second luminous body to the whole of the resin is usually 10 to 95%, preferably 20 to 90%, more preferably. Is 30-80%. If the phosphor is too much, the luminous efficiency may be reduced due to aggregation of the powder, and if it is too little, the luminous efficiency may be lowered due to light absorption or scattering by the resin.

  The light emitting device of the present invention includes the phosphor as a wavelength conversion material and a light emitting element that emits light of 350 to 415 nm, and the phosphor absorbs light of 350 to 415 nm emitted from the light emitting element. In addition, it is a light emitting device that has good color rendering properties and can generate high-intensity visible light regardless of the use environment, and a light source such as a backlight light source and a traffic light, and an image display device such as a color liquid crystal display. And suitable for light sources such as lighting devices such as surface emitting.

  The light emitting device of the present invention will be described with reference to the drawings. FIG. 4 is a schematic cross-sectional view showing one embodiment of a light emitting device having a first light emitter (350-415 nm light emitter) and a second light emitter. 4 is a light emitting device, 5 is a mount lead, 6 is an inner lead, 7 is a first light emitter (350-415 nm light emitter), 8 is a phosphor-containing resin portion as a second light emitter, 9 Is a conductive wire, and 10 is a mold member.

  As shown in FIG. 4, the light emitting device as an example of the present invention has a general bullet shape, and a first light emitter made of a GaN-based light emitting diode or the like is disposed in the upper cup of the mount lead 5. (350-415 nm illuminant) 7 is a phosphor formed as a second illuminant by mixing and dispersing the phosphor in a binder such as silicon resin, epoxy resin or acrylic resin and pouring it into the cup. It is fixed by being covered with the body-containing resin portion 8. On the other hand, the first light emitter 7 and the mount lead 5, and the first light emitter 7 and the inner lead 6 are each electrically connected by a conductive wire 9, and these are entirely covered with a mold member 10 made of epoxy resin or the like, Protected.

  Further, as shown in FIG. 5, the surface emitting illumination device 11 incorporating the light emitting element 1 has a large number of light emission on the bottom surface of a rectangular holding case 12 whose inner surface is light-opaque such as a white smooth surface. The device 13 is arranged with a power supply and a circuit (not shown) for driving the light emitting device 13 provided outside thereof, 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 apply light to the first light emitter of the light emitting element 13 to emit light of 350 to 415 nm, and a part of the light emission is used as the second light emitter. The phosphor in the phosphor-containing resin part absorbs and emits visible light, while light emission with high color rendering properties is obtained by mixing with blue light or the like that is not absorbed by the phosphor. 14, 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.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

EuF ₃ ; 0.01227 mol, CsF; 0.1023 mol, CaF ₂ ; 0.0184 mol, and MgF ₂ ; 0.0716 mol, together with pure water, ground in an agate mortar, mixed and dried. The resulting mixture was baked in an alumina crucible by heating at 950 ° C. for 24 hours under a nitrogen gas flow containing 4% hydrogen, and subsequently subjected to particle size control by pulverization to produce a blue-green phosphor. CsCa _0.18 Mg _0.7 Eu _0.12 F ₃ (phosphor used for the second phosphor) was produced. FIG. 6 shows the X-ray diffraction pattern of this phosphor. The main peak group in FIG. 6 matches the peak pattern of trigonal Cs ₂ NaCrF _{6 in} FIG. 2, and it can be seen that the target crystal phase is generated.

FIG. 7 shows an emission spectrum when the phosphor is excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. FIG. 7 also shows emission spectra of a known blue phosphor Ba _0.9 Eu _0.1 MgAl ₁₀ O ₁₇ (Reference Example 1) and a green phosphor Sr _0.99 Eu _0.01 Ga ₂ S ₄ (Reference Example 2) as reference examples. Conditions for producing both phosphors are shown below.

The charged materials were BaCO ₃ ; 0.0103 mol, basic magnesium carbonate (Mg mole number 0.0114 mol), γ-Al ₂ O ₃ ; 0.0570 mol, and Eu ₂ O ₃ ; 0.00057 mol. CsCa _0.18 Mg _0.7 except that the firing conditions were changed to 1600 ° C. and 2 hours.
Ba _0.9 Eu _0.1 MgAl ₁₀ O ₁₇ having a conventional commercially available blue phosphor composition was obtained by manufacturing in the same manner as Eu _0.12 F ₃ . Ga ₂ S ₃ ; 0.058 mol, SrS; 0.058 mol, and EuF ₃ ; 0.00058 mol were pulverized and mixed in an agate mortar and dried. Firing was performed by heating at 1000 ° C. for 8 hours under a gas flow, and subsequently, particle size control by pulverization was performed to obtain Sr _0.99 Eu _0.01 Ga ₂ S ₄ having a green phosphor composition.

As seen in FIG. 7, the blue-green phosphor of Example 1 has a strong emission peak that can compensate for the valleys of the emission spectra of known blue and green phosphors, so that color rendering can be improved in a small amount. In addition, since the half width of the strong emission peak is sufficiently large, it can be seen that there is also an effect of increasing the intensity of the blue and green peaks. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. Table 1 also shows the emission peak wavelength, relative emission intensity, and half-value width of Reference Examples 1 and 2. The full width at half maximum of CsCa _0.18 Mg _0.7 Eu _0.12 F ₃ is not significantly different from the difference between the blue and green peak wavelengths (79 nm) of Reference Examples 1 and 2, in other words, it has a sufficiently large half width, and Reference Examples 1 and 2 It can be seen that the light emission intensity is larger than the light emission intensity.

Phosphor as in Example 1 except that the raw materials were changed to EuF ₃ ; 0.02384 mol, CsF; 0.0954 mol, CaF ₂ ; 0.0048 mol, and MgF ₂ ; 0.06676 mol CsCa _0.05 Mg _0.7 Eu _0.25 F ₃ was produced. The phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode, and the emission spectrum was measured. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. CsCa _0.05 Mg _0.7 Eu _0.25 F ₃ does not differ greatly from the difference between the peak wavelengths of blue and green in Reference Examples 1 and 2 of 79 nm. In other words, the CsCa _0.05 Mg _0.7 Eu _0.25 F ₃ has a sufficiently large half width and is larger than the emission intensity of Reference Examples 1 and 2. It turns out that it has luminescence intensity.

Phosphors in the same manner as in Example 1 except that the charged raw materials were changed to EuF ₃ ; 0.005322 mol, CsF; 0.1064 mol, CaF ₂ ; 0.0266 mol, and MgF ₂ ; 0.07451 mol CsCa _0.25 Mg _0.7 Eu _0.05 F ₃ was produced. FIG. 8 shows the X-ray diffraction pattern of this phosphor. It can be seen that the main peak group in FIG. 8 matches the peak pattern of trigonal Cs ₂ NaCrF ₆ in FIG. The phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode, and the emission spectrum was measured. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. CsCa _0.25 Mg _0.7 Eu _0.05 F ₃ does not differ greatly from the difference between the peak wavelengths of blue and green in Reference Examples 1 and 2 of 79 nm, in other words, has a sufficiently large half-value width and is larger than the emission intensity of Reference Examples 1 and 2. It turns out that it has luminescence intensity.

Phosphor as in Example 1 except that the raw materials were changed to EuF ₃ ; 0.00163 mol, CsF; 0.1086 mol, CaF ₂ ; 0.0310 mol, and MgF ₂ ; 0.07605 mol CsCa _0.285 Mg _0.7 Eu _0.015 F ₃ was produced. FIG. 9 shows the X-ray diffraction pattern of this phosphor. It can be seen that the main peak group in FIG. 9 matches the peak pattern of trigonal Cs ₂ NaCrF ₆ in FIG. The phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode, and the emission spectrum was measured. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. CsCa _0.285 Mg _0.7 Eu _0.015 F ₃ is not significantly different from the difference between the peak wavelengths of blue and green in Reference Examples 1 and 2 of 79 nm. In other words, the CsCa _0.285 Mg _0.7 Eu _0.015 F ₃ has a sufficiently large half width and is larger than the emission intensity of Reference Examples 1 and 2. It turns out that it has luminescence intensity.

Phosphor as in Example 1 except that the raw materials were changed to EuF ₃ ; 0.005055 mol, CsF; 0.1011 mol, MgF ₂ ; 0.07078 mol, and SrF ₂ ; 0.0253 mol the CsSr _0.25 Mg _0.7 Eu _0.05 F ₃ was produced. The phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode, and the emission spectrum was measured. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. CsSr _0.25 Mg _0.7 Eu _0.05 F ₃ does not differ greatly from the difference between the peak wavelengths of blue and green in Reference Examples 1 and 2 of 79 nm, in other words, has a sufficiently large half-value width and matches the emission intensity of Reference Examples 1 and 2. It can be seen that it has only a large emission intensity.

Phosphor CsCa _0.95 in the same manner as in Example 1 except that the raw materials were changed to EuF ₃ ; 0.005073 mol, CsF; 0.1015 mol, and CaF ₂ ; 0.0964 mol.
Eu _0.05 F ₃ was produced. FIG. 10 shows the X-ray diffraction pattern of this phosphor. It can be seen that the peak pattern of FIG. 10 substantially matches the peak pattern of the cubic CsCaF ₃ of FIG. The phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode, and the emission spectrum was measured. Table 1 shows the wavelength of the emission peak, the relative emission intensity, and the half width. It can be seen that CsCa _0.95 Eu _0.05 F ₃ has a half-value width greater than 79 nm between the blue and green peak wavelengths of Reference Examples 1 and 2, and a large emission intensity corresponding to the emission intensity of Reference Examples 1 and 2. .

X-ray diffraction pattern of CsCaF ₃ (X-ray source: converted to CuKα). X-ray diffraction pattern of Cs ₂ NaCrF ₆ (X-ray source: converted to CuKα). The figure which shows an example of the light-emitting device which made the film-like fluorescent substance contact or shape | mold to the surface emitting GaN-type diode. It is typical sectional drawing which shows one Example of the light-emitting device comprised from the fluorescent substance in this invention, and a 1st light-emitting body (350-415 nm light-emitting body). The typical sectional view showing an example of the surface emitting illumination device of the present invention. X-ray diffraction pattern (X-ray source: CuKα) of the phosphor of Example 1 of the present invention A spectrum obtained by superimposing the emission spectra of the phosphors of Example 1, Reference Example 1, and Reference Example 2 of the present invention irradiated by a GaN-based light emitting diode having an emission wavelength of 400 nm. X-ray diffraction pattern (X-ray source: CuKα) of the phosphor of Example 3 of the present invention X-ray diffraction pattern (X-ray source: CuKα) of the phosphor of Example 4 of the present invention X-ray diffraction pattern (X-ray source: CuKα) of the phosphor of Example 6 of the present invention

Explanation of symbols

1; second light emitter 2; surface-emitting GaN-based LD
3; Substrate 4; Light emitting device 5; Mount lead 6; Inner lead 7; First light emitter (light emitter of 350 to 415 nm)
8; Resin part containing phosphor in the present invention 9; Conductive wire 10; Mold member 11; Surface-emitting illumination device 12 incorporating a light-emitting element; Holding case 13; Light-emitting device 14;

Claims (11)

Phosphor having a crystal phase having a chemical composition of the following one general formula [1].

(In the above general formula [1], A is Cs, M is Mg, Ca, a divalent metal element selected from Sr, X table but a halogen element, or 70 mol% is F, a is a number satisfying 0.01 ≦ a ≦ 0.25 .) The phosphor according to claim 1, wherein the ratio of Mg in M is 50 mol% or more. The phosphor according to claim 1 or 2 , wherein the element M contains Ca or Sr. A first light emitter which emits light of 350-415Nm, used in the second luminous body of the light emitting device and a second luminous body which emits visible light when irradiated with light from the first luminous body The phosphor according to any one of claims 1 to 3, wherein In a light-emitting device including a first light-emitting body that generates light of 350 to 415 nm and a second light-emitting body that generates visible light when irradiated with light from the first light-emitting body, the second light-emitting body includes: A light-emitting device comprising the phosphor according to any one of claims 1 to 3. 6. The light emitting device according to claim 5 , wherein the first light emitter is a laser diode or a light emitting diode. The light emitting device according to claim 5 or 6 , wherein the first light emitter is made of a GaN-based compound semiconductor. First light emitter emitting device according to any one of claims 5 to 7, characterized in that a surface-emitting type GaN-based laser diode. The second powder of silicon resin emitters, and / or according to any one of claims 5 to 8, characterized in that to irradiate the light of the first from the light emitters are dispersed in an epoxy resin Light-emitting device. Lighting device comprising a light-emitting device according to any one of claims 5 to 9. An image display device having a light-emitting device according to any one of claims 5 to 9.

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