JP2005226069A - Phosphor and light emitting device using the same, lighting device, and image displaying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deep red phosphor imparting high color rendering properties or a brilliant white phosphor imparting high color rendering properties and to provide a light emitting device emitting visible lights with high luminescence intensity, by combining the phosphors with a stimulation source which emits the light of 350 to 430 nm. <P>SOLUTION: The phosphor has a crystal phase having chemical composition expressed by general formula [1]. The light emitting device is combined the phosphor and a light emitting source which emits the light of 350 to 430 nm, for irradiation of the light. In the formula, M<SP>1</SP>is an element selected from a group comprising monovalent, divalent, trivalent and pentavalent elements, wherein the ratio of divalent elements is ≥80 mol.%, the ratio of sum of Ba, Ca and Sr is ≥40 mol.%, the ratio of sum of Ba and Ca (molar ratio) is less than 0.2, M<SP>2</SP>is the tetravalent element containing Si and Ge and the sum of the Si and Ge is ≥90 mol.%, Z is a monovalent, divalent elements, H, N or the like elements, for example the phosphor is expressed by Ba<SB>0.935</SB>Mg<SB>0.935</SB>Eu<SB>0.1</SB>Mn<SB>0.03</SB>SiO<SB>4</SB>. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a highly efficient light-emitting device obtained by combining a phosphor that emits light in the near ultraviolet to visible region and a phosphor that absorbs this light and emits visible light having a longer wavelength, and the phosphor itself.
In general, white light essential for display and illumination is obtained by combining light emission of blue, green, and red by the additive mixing principle of light. In the display, in order to efficiently reproduce a wide range of colors on the chromaticity coordinates, the blue, green, and red light emitters must have as high emission intensity as possible and good color purity. In general lighting, depending on the light emission efficiency and application, it is necessary that the color of the illuminated object looks the same as when illuminated by natural light, that is, so-called color rendering is high. A fluorescent lamp, which is a typical illumination, uses a mixture of three types of phosphors that emit light of 450, 540, and 610 nm, which is sensitive to the human eye, using ultraviolet light of 254 nm by mercury discharge as an excitation source. Realized highly efficient lighting. However, in the present situation, phosphors having high emission efficiency have not been developed when the wavelength of excitation light is in the near ultraviolet to visible region. In particular, there is a demand for the development of red phosphors having excellent performance because the emission efficiency of red phosphors is lower than that of blue and green for excitation light in this wavelength range. In addition, if any two or three luminescences of 450, 540, and 610 nm are obtained from one phosphor, the preparation process can be simplified and stable performance can be expected compared to mixing three types of phosphors. Not done.

Various phosphors that emit blue, green, and red light in combination with a light source that emits light in the near ultraviolet to visible region are exemplified in Patent Document 1. Among them, it is described that alkaline earth metal silicate phosphors emit light in blue and red, and Patent Document 2 discloses (Ba, Ca, Sr, Mg) -Si activated by Eu ^2+. In the case of only Ba and Ca in the -O system, light is emitted at 505 nm, and when Sr is added, the light emission wavelength is shifted to 580 nm. Non-Patent Document 1 reports on (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu, Mn. In Non-Patent Document 2, B
It is described that a ₃ MgSi ₂ O ₈ : Eu, Mn has an emission peak at 442,505,620 nm and the crystal structure is merwinite.
JP-T-2004-505470 Special table 2004-501512 gazette J. et al. Electrochem. Soc, Vol. 115, No7, 733-738 (1968) Appl. Phys. Lett. , Vol. 84, no. 15, 2931-2933 (2004)

  The purpose is to develop a high-efficiency red light-emitting phosphor and a white phosphor for use in a display or illumination that emits light with high efficiency in combination with a light source emitting near-ultraviolet to visible light.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that an alkaline earth silicate phosphor having a new composition and a specific crystal structure enhances red or white light against excitation light in the near ultraviolet to visible region. The present invention was completed by finding that light is emitted efficiently.
Specifically, an M ₂ SiO ₄ type silicate containing Ba and Ca activated by Eu and Mn was found, and the present invention was achieved. In particular, the red phosphor of the present invention has a feature that it emits redness that is felt bright because its emission peak wavelength is in the range of 590-620 nm.

That is, the first aspect of the present invention is a phosphor having a crystal phase having a chemical composition represented by the following general formula [1], the first illuminant that emits light of 350 to 430 nm, and the first In a light emitting device having a second light emitter that generates visible light upon irradiation of light from the light emitter, the second light emitter has a crystal phase having a chemical composition represented by the following general formula [1] A light emitting device characterized in that is a second gist thereof.

(However, M ¹ is at least one element selected from the group of divalent elements other than monovalent elements, Eu, Mn, and Mg, trivalent elements, and pentavalent elements. The proportion of the element is 80 mol% or more, the proportion of the total of Ba, Ca, and Sr is 40 mol% or more, and the proportion (molar ratio) of Ca to the sum of Ba and Ca is less than 0.2. ² represents a tetravalent element group containing 90 mol% or more of Si and Ge in total, and Z is at least one element selected from the group consisting of −1 and −2 elements, H and N. A is 0.01 <a ≦ 0.8, b is 0 <b ≦ 0.8, c and d are 0 <c / (c + d) ≦ 0.2, or 0.3 ≦ c / (c + d) ≦. 0.8, a, b, c, d is 1.8
≦ (a + b + c + d) ≦ 2.2, e and f are numbers satisfying 0 ≦ f / (e + f) ≦ 0.035 and 3.6 ≦ (e + f) ≦ 4.4. )

  ADVANTAGE OF THE INVENTION According to this invention, the phosphor which emits deep red or bright white can be obtained, and the light-emitting device which emits visible light with high color rendering property efficiently can be provided.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.
The present invention is a phosphor having a crystal phase having a chemical composition of the following general formula [1], a phosphor having a crystal phase having a chemical composition of the following general formula [1], and a phosphor having a crystal phase of 350 to 430 nm. And a light emitting device for irradiating light.

M ¹ in the formula [1] is a monovalent element, a divalent element excluding Eu, Mn, and Mg, a trivalent element,
It represents at least one element selected from the group of pentavalent elements, the proportion of divalent elements is 80 mol% or more, the proportion of the total of Ba, Ca, and Sr is 40 mol% or more, and Ba and It satisfies the condition that the ratio (molar ratio) of Ca to the total of Ca is less than 0.2.

When elements other than Ba, Ca, and Sr are specifically described, examples of monovalent elements include Li, Na, K, Rb, and Cs. Examples of divalent elements include V, Cr, Fe, and Co. , Ni, Cu, Zn, Mo, Ru, Pd, Ag, Cd, Sn, Sm, Tm, Yb, W, Re, Os, Ir, Pt, Hg, Pb, and the like. B, Al, Ga, In, and the like, and rare earth elements such as Y, Sc, and the like. Examples of the pentavalent element include, but are not limited to, P, Sb, Bi, and the like. Among them, in divalent elements, V, Zn, M
o, Sn, Sm, Tm, Yb, W, and Pb hardly affect the performance.

A total of 20 mol% of monovalent, trivalent, and pentavalent elements is used to aid crystallization of silicate by diffusion in the solid during firing of divalent elements and activators Eu ²⁺ and Mn ²⁺ in M ^1. May be introduced within.
In terms of a deep red component or the like, the ratio (molar ratio) of Ca to the total of Ba and Ca is preferably less than 0.1, and more preferably 0. From the viewpoint of red or white emission intensity, the proportion of the total of Ba, Ca, Sr is preferably 80 mol% or more, more preferably the proportion of the total of Ba, Ca is 80 mol% or more, More preferably, the ratio of the total of Ba, Ca and Sr is 100 mol%.

M ² in the formula [1] represents a tetravalent element group containing 90 mol% or more of Si and Ge in total, but M ² contains 80 mol% or more of Si in terms of red or white emission intensity. It is more preferable that M ² is made of Si. Examples of tetravalent elements other than Si and Ge include Zn, Ti, Hf, and the like, and these may be included within a range that does not impair the performance in terms of red or white emission intensity.

  Z in the formula [1] is at least one element selected from the group consisting of a −1 valent element, a −2 valent element, H, and N. For example, S, which is a −2 valent element similar to oxygen, In addition to Se and Te, it may be −1 valent F, Cl, Br, I, etc., OH group may be contained, and oxygen group is partially changed to ON group or N group. Also good. Z may be contained to such an extent that the fluorescent performance is not affected, that is, the impurity level to the total element ratio is about 2 mol% or less. This corresponds to a molar ratio of Z to (Z + oxygen atom) of 0.035 or less. Therefore, the range of f / (e + f), which is the molar ratio of Z to (Z + oxygen atom), is 0 ≦ f / (e + f) ≦ 0.035. From the viewpoint of phosphor performance, f / (e + f) ≦ 0.01 is preferable, and f / (e + f) = 0 is more preferable.

Regarding the Eu molar ratio a in the formula [1], a is a number satisfying 0.0003 ≦ a ≦ 0.8. If the molar ratio “a” of the luminescent center ion Eu ²⁺ is too small, the luminescence intensity tends to decrease, and is preferably 0.001 or more, more preferably 0.01 or more. On the other hand, if the amount is too large, the emission intensity tends to decrease due to a phenomenon called concentration quenching or temperature quenching. As an upper limit, a ≦ 0.5 is more preferable.

The Mn molar ratio b in the formula [1] is a factor that determines whether to emit red light or white light. When b is 0, a red peak is not obtained and only a blue or blue-green peak is obtained. However, when b takes a small positive value, a red peak appears in the blue and green peaks, and the whole emits white light, and when b takes a larger positive value, the blue and green peaks become very small and red. The peak is the main. The range of b is 0 <b ≦ 0.8 as a red phosphor or a white phosphor. Energy Eu ²⁺ phosphor has excited by the irradiation of the excitation light source is moved to Mn ^2+, it believed that Mn ²⁺ is red-emitting, energy mainly by the composition of M ¹ and M ² Since the degree of movement is slightly different, the boundary value of b for switching from the red phosphor to the white phosphor is somewhat different depending on the composition of M ¹ and M ² . Therefore, the good range of b of red light emission and white light emission cannot be strictly distinguished, but 0.002 ≦ b ≦ 0.6 is more preferable from the viewpoint of the intensity of the light emission color including red and white, and 0 0.005 ≦ b ≦ 0.4 is more preferable. In the present invention, “white” is to be interpreted in a broad sense, and means that there are two or more maximum values in the emission spectrum, each of which is a broadband emission peak.

Mg in the formula [1] is substituted by M ¹ which is mainly a divalent element, and c and d which are the ratio of the number of moles of Mg to the total number of moles of Mg and M ¹ are 0 <c / (c + d) ≦ 0.2, or 0.3 ≦ c / (c + d) ≦ 0.8. From the viewpoint of red or white emission intensity, c and d are 0 <c /
(C + d) ≦ 0.2 or 0.3 ≦ c / (c + d) ≦ 0.7 is preferable.
In the crystal phase Eu _a Mn _b Mg _c M ¹ _d M ² O _e Z _f of the general formula [1], Eu ²⁺ , Mn ²⁺ , and Mg ²⁺ are replaced with M ¹ mainly composed of a divalent element. M ² is mainly occupied by Si and Ge, the anion is mainly oxygen, and the basic composition is M ¹ , M ³ , and the total molar ratio of oxygen atoms is 2, ¹ , 4 respectively. However, even if some cation deficiency or anion deficiency occurs, the fluorescence performance for this purpose is not greatly affected. Therefore, when the total molar ratio of M ² mainly occupied by Si and Ge is fixed to 1 in the chemical formula, The molar ratio (a + b + c + d) of M ¹ + Eu + Mn + Mg is 1.8 ≦ (
a + b + c + d) ≦ 2.2, preferably 1.9 ≦ (a + b + c + d) as the lower limit, (a + b + c + d) ≦ 2.1, and more preferably (a + b + c + d) = 2. Further, (e + f), which is the total molar ratio of sites on the anion side, is in a range of 3.6 ≦ (e + f) ≦ 4.4, and preferably has a lower limit of 1.9 ≦ (e + f) and an upper limit of ( e + f) ≦ 2.1 is preferable, and it is more preferable that e = 4 and f = 0.

The phosphor used in the present invention includes an M ¹ source, an M ² source, an Mg source, and Eu and Mn element source compounds as shown in the general formula [1] described below (A ) Or (B) can be produced by heat-treating the mixture prepared by the mixing method.
(A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., pulverization using mortar and pestle, etc., mixer such as ribbon blender, V-type blender and Henschel mixer, or mortar and pestle Dry mixing method combined with mixing.
(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 activator element, it is preferable to use a liquid medium because it is necessary to uniformly mix and disperse a small amount of the compound, and other elements The latter wet method is also preferred from the viewpoint of obtaining uniform mixing throughout the source compound, and as the heat treatment method, in a heat-resistant container such as a crucible or a tray using a material having low reactivity with the phosphor, Usually, it is made by heating at a temperature of 750 to 1400 ° C., preferably 900 to 1300 ° C., for 10 minutes to 24 hours in a single or mixed atmosphere of a gas such as 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 activating element contributes to light emission is selected. In the case of divalent Eu and Mn in the present invention, a neutral or reducing atmosphere such as carbon monoxide, nitrogen, hydrogen, and argon is preferable, but a reducing atmosphere containing carbon monoxide and hydrogen is more preferable. More preferably, carbon is present in the atmosphere. Specifically, it is achieved by heating using a carbon heater furnace, heating using a container such as a carbon crucible in a reducing atmosphere, heating in which carbon beads or the like coexist in the reducing atmosphere, and the like.

Here, as the element source compounds of the M ¹ source, M ² source, Mg source, and activator element, M ¹ ,
M ² , Mg, and each of the oxides, hydroxides, carbonates, nitrates, sulfates, oxalates of the activating elements,
Carboxylic acid salts, halides and the like can be mentioned, and these are selected in consideration of reactivity to the composite oxide and non-generation of NOx, SOx, etc. during firing.
The Ba listed as M ^1, Ca, the Sr, if specific examples thereof M ¹ source compound, as a Ba source _{compound, BaO, Ba (OH) 2} · 8H 2 O, BaCO 3
, Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (OCO) ₂ .2H ₂ O, Ba (OCOCH ₃ ) ₂ , B
aCl _{2 and the} like, and Ca source compounds include CaO, Ca (OH) ₂ , CaCO ₃ , Ca (
NO ₃ ) ₂ · 4H ₂ O, CaSO ₄ · 2H ₂ O, Ca (OCO) ₂ · H ₂ O, Ca (OCOCH _3
2 · H ₂ O, CaCl _{2 and the} like, and Sr source compounds include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (OCO) ₂・ H ₂ O, Sr (OCO
CH ₃ ) ₂ · 0.5H ₂ O, SrCl _{2 and the} like.

Specific examples of the M ² source compounds for the Si and Ge mentioned as M ² include SiO ₂ , H ₄ SiO ₄ , Si (OCOCH ₃ ) _4, etc. Examples of the Ge source compound include GeO ₂ , Ge (OH) ₄ , Ge (OCOCH ₃ ) ₄ , and GeCl ₄ .
For Mg, specific examples of Mg source compounds include MgO, Mg (OH) ₂ , MgC
O ₃ , Mg (OH) ₂ .3MgCO ₃ .3H ₂ O, Mg (NO ₃ ) ₂ .6H ₂ O, MgSO ₄ , Mg (OCO) ₂ .2H ₂ O, Mg (OCOCH ₃ ) ₂ .4H ₂ O , MgCl _{2 and the} like.

Further, with respect to Eu and Mn mentioned as the activation elements, specific examples of the element source compounds include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (OCO) ₆ , EuCl ₂ and EuCl. _Three
Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, MnO ₂ , Mn ₂ O ₃ , Mn ₃ O ₄
, MnO, Mn (OH) ₂ , MnCO ₃ , Mn (OCOCH ₃ ) ₂ .2H ₂ O, Mn (OCO
CH ₃ ) ₃ · nH ₂ O, MnCl ₂ · 4H ₂ O and the like.

In the present invention, the first light emitter that irradiates the phosphor with light generates light having a wavelength of 350 to 430 nm. Preferably, a light emitter that generates light having a peak wavelength in the wavelength range of 350 to 430 nm is used. Specific examples of the first light emitter include a light emitting diode (LED) or a laser diode (LD). A laser diode is more preferable because it consumes 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, those having an In _X Ga _Y N light-emitting layer are particularly preferable because the emission intensity is very strong, and in GaN-based LDs, the multiple quantum of the In _X Ga _Y N layer and the GaN layer is preferred. A 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. 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. Those having a heterostructure sandwiched between Ga _Y N layers and the like have high luminous efficiency, and those having a heterostructure having a quantum well structure have higher luminous efficiency and are 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 type 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 to have a shape in which is contacted. Contact here refers to creating 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. 1 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. 1, 1 is a film-like second light emitter having the phosphor, 2 is a surface-emitting GaN-based LD as the 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 their surfaces may be brought into contact with each other by an adhesive or other means. Alternatively, the second light emitter may be formed (molded). 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 the resin that can be used in this case include various resins such as silicon resin, epoxy resin, polyvinyl resin, polyethylene resin, polypropylene resin, and polyester resin, which are preferable in terms of good dispersibility of the phosphor powder. Is a silicon resin or an epoxy resin. 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 generates 350-430 nm light, and the phosphor absorbs 350-430 nm light emitted from the light-emitting element. In addition, the phosphor having a good color rendering property and capable of generating high-intensity visible light regardless of the use environment, and the phosphor having the crystal phase of the present invention constituting the light-emitting device has a wavelength of 350 to 430 nm. By emitting light from the first light-emitting body that generates the light, light is emitted in a wavelength region representing red or white. The light-emitting device of the present invention is suitable for a light source such as a backlight source, a light source such as a traffic light, an image display device such as a color liquid crystal display, and a lighting device such as a surface light source.

  The light emitting device of the present invention will be described with reference to the drawings. FIG. 2 is a schematic cross-sectional view showing an embodiment of a light emitting device having a first light emitter (350-430 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 (350-430 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. 2, 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. (350-430 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. 3, 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, by driving the surface emitting illumination device 11 and applying a voltage to the first light emitter of the light emitting element 13, light of 350 to 430 nm is emitted, 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.

Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, Mn (NO ₃ ) ₂ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, SiO ₂ molar ratio 0.935: 0.935: 0.1: 0.03: 1) was mixed in a platinum container, dried and heated at 1050 ° C. for 2 hours under a nitrogen gas flow containing 4% hydrogen. The phosphor Ba _0.935 Mg _0.935 Eu _0.1 Mn _0.03 SiO ₄ (phosphor used for the second light emitter) was manufactured. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength of the emission peak, the intensity of the emission peak (hereinafter referred to as relative intensity), and the half width when the intensity of the emission peak of Comparative Example 5 described later is 100. Since the present phosphor has sufficiently large intensity and half width, it emits strong red light giving high color rendering properties and emits bright deep red light because the peak wavelength is in the region of 615-645 nm. According to the measurement of the excitation spectrum at the peak wavelength of 630 nm in the excitation at 400 nm, the relative intensities at the excitation wavelengths of 254 nm, 280 nm, 382 nm, and 400 nm are 208, 328, 351, and 320, respectively. In addition, it can be seen that the light emission by excitation near 400 nm is 1.5 times or more stronger, and this phosphor is a very advantageous phosphor for the light source of the GaN-based semiconductor.
(Comparative Example 1)
Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal silica (SiO ₂ ) suspension (Ba (NO ₂ ) ₃ ) ₂ , Mg (N
The molar ratio of O ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, SiO ₂ is 0.95: 0.95:
Phosphor Ba _0.95 Mg _0.95 Eu _0.1 SiO ₄ was produced in the same manner as in Example 1 except that 0.1: 1) was used as the stock solution. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. It can be seen that when Mn is not added in the composition of Example 1, no red peak appears.

Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, Mn (NO ₃ ) ₂ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, the molar ratio of SiO ₂ is 0.623: 1.247: 0.1: 0.03: 1) except for using as a stock solution were charged, phosphor Ba in the same manner as in example 1 _0.623 Mg _1.247 Eu _0.1 Mn _0.03 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. Since the present phosphor has sufficiently large intensity and half width, it emits strong red light giving high color rendering properties and emits bright deep red light because the peak wavelength is in the region of 615-645 nm.

(Comparative Example 2)
Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal silica (SiO ₂ ) suspension (Ba (NO ₂ ) ₃ ) ₂ , Mg (N
The molar ratio of O ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, SiO ₂ is 0.633: 1.26.
A phosphor Ba _0.633 Mg _1.267 Eu _0.1 SiO ₄ was produced in the same manner as in Example 1 except that 7: 0.1: 1) was used as the stock solution. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. It can be seen that the red peak does not appear if Mn is not added in the composition of Example 2.

Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, Mn (NO ₃ ) ₂ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, The phosphor Ba _0.587 Mg _1.173 Eu _0.2 Mn was _{prepared in the same} manner as in Example 1 except that the molar ratio of SiO ₂ was 0.587: 1.173: 0.2: 0.04: 1). _0.04 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. FIG. 4 shows the emission spectrum. In order to remove the influence of the excitation light source on the emission spectrum, measurement is performed by introducing a filter that cuts light of 420 nm or less. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. Since the present phosphor has sufficiently large intensity and half width, it emits strong red light giving high color rendering properties and emits bright deep red light because the peak wavelength is in the region of 615-645 nm.

(Comparative Example 3)
Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal silica (SiO ₂ ) suspension (Ba (NO ₂ ) ₃ ) ₂ , Mg (N
The molar ratio of O ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, SiO ₂ is 0.6: 1.2: 0.
Phosphor Ba _0.6 in the same manner as in Example 1 except that 2: 1) is used as the stock solution.
Mg _1.2 Eu _0.2 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. It can be seen that when Mn is not added in the composition of Example 3, no red peak appears.

(Comparative Example 4)
An aqueous solution of Ba (NO ₃ ) _2, an aqueous solution of Eu (NO ₃ ) ₃ .6H ₂ O, an aqueous solution of Mn (NO ₃ ) ₂ .6H ₂ O, and a suspension of colloidal silica (SiO ₂ ) (Ba (NO ₃ ) ₂ , Eu (N
Example 3 except that the molar ratio of O ₃ ) ₃ · 6H ₂ O, Mn (NO ₃ ) ₂ , SiO ₂ is 1.7: 0.2: 0.1: 1) is used as the stock solution. Similarly, a phosphor Ba _1.7 Eu _0.2 Mn _0.1 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. It can be seen that even if Mn is contained in the crystal, the red peak does not appear without Mg.

(Comparative Example 5)
Ba (NO ₃ ) ₂ aqueous solution, Ca (NO ₃ ) ₂ .4H ₂ O aqueous solution, Mg (NO ₃ ) ₂ .6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ .6H ₂ O aqueous solution, Mn ( NO ₃ ) ₂ · 6H ₂ O aqueous solution and colloidal silica (SiO ₂ ) suspension (Ba (NO ₃ ) ₂ , Ca (NO ₃ ) ₂ , Mg (
The molar ratio of NO ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, Mn (NO ₃ ) ₂ · 6H ₂ O, SiO ₂ is 0.567: 0.567: 0.566: 0. 0.2: 0.1: 1) was used in the same manner as in Example 1 except that phosphor Ba _0.567 Ca _0.567 Mg _0.566 Eu _0.2 Mn _0.1 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 1 shows the wavelength, relative intensity, and half-value width of the emission peak. It can be seen that if the amount of Ca in the crystal is too much relative to Ba, the peak wavelength is less than 615 nm, and vivid deep red light cannot be emitted.

Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, Mn (NO ₃ ) ₂ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, The phosphor Ba _0.92 Mg _0.92 Eu _0.1 Mn was prepared in the same manner as in Example 1 except that the molar ratio of SiO ₂ was 0.92: 0.92: 0.1: 0.06: 1). _0.06 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. FIG. 5 shows the emission spectrum. Table 2 shows the wavelength and relative intensity of a peak of 590 nm or more (the peak of the red component), the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, the x value of the chromaticity coordinates representing the color, y Indicates the value. A wide spectrum including a deep red component with a peak wavelength in the range of 615 nm to 645 nm and a blue / green component is obtained, giving high color rendering properties and bright white light. It turns out that it is light emission.

  Note that the maximum peak of less than 590 nm refers to the peak with the highest intensity when a plurality of peaks are present in the region of less than 590 nm in the emission spectrum, and refers to that in the case of a single peak. The half width of the peak group is a measure for knowing how widely the emission spectrum is distributed and how high the color rendering is, and as shown in FIG. 6, the intensity of the maximum peak in the emission spectrum. Is defined as the sum of the widths of the wavelength regions having an intensity of more than half.

(Comparative Example 6)
Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal silica (SiO ₂ ) suspension (Ba (NO ₂ ) ₃ ) ₂ , Mg (N
The molar ratio of O ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, SiO ₂ is 0.95: 0.95:
A white light emitting phosphor Ba _0.95 Mg _0.95 Eu _0.1 SiO ₄ was produced in the same manner as in Example 1 except that 0.1: 1) was used as the stock solution. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. It can be seen that the red peak does not appear when Mn is not added in the composition of Example 4.

(Comparative Example 7)
Ba (NO ₃ ) ₂ aqueous solution, Ca (NO ₃ ) ₂ · 4H ₂ O aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Ca (NO ₃ ) ₂ .4H ₂ O, Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, The phosphor Ba _1.2 Ca _0.2 Mg _0.4 E was used in the same manner as in Example 1 except that the molar ratio of SiO ₂ was 1.2: 0.2: 0.4: 0.2: 1).
u _0.2 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. It can be seen that the red peak does not appear unless Mn is added in the composition of Example 5.

Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, Mn (NO ₃ ) ₂ · 6H ₂ O aqueous solution, and colloidal Silica (SiO ₂ ) suspensions (Ba (NO ₃ ) ₂ , Mg (NO ₃ ) ₂ .6H ₂ O, Eu (NO ₃ ) ₃ .6H ₂ O, Mn (NO ₃ ) ₂ .6H ₂ O, The phosphor Ba _0.82 Mg _0.82 Eu _0.3 Mn was prepared in the same manner as in Example 1 except that the molar ratio of SiO ₂ was 0.82: 0.82: 0.3: 0.06: 1). _0.06 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. Wide spectrum including deep red component in peak wavelength range of 615-645nm and blue / green component is obtained, giving high color rendering and bright white light emission It turns out that it is.

(Comparative Example 8)
Ba (NO ₃ ) ₂ aqueous solution, Mg (NO ₃ ) ₂ · 6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ · 6H ₂ O aqueous solution, and colloidal silica (SiO ₂ ) suspension (Ba (NO ₂ ) ₃ ) ₂ , Mg (N
The molar ratio of O ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, SiO ₂ is 0.85: 0.85:
A phosphor Ba _0.85 Mg _0.85 Eu _0.3 SiO ₄ was produced in the same manner as in Example 1 except that 0.3: 1) was used as the stock solution. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. It can be seen that the red peak does not appear when Mn is not added in the composition of Example 6.

(Comparative Example 9)
Ba (NO ₃ ) ₂ aqueous solution, Ca (NO ₃ ) ₂ .4H ₂ O aqueous solution, Mg (NO ₃ ) ₂ .6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ .6H ₂ O aqueous solution, Mn ( NO ₃ ) ₂ · 6H ₂ O aqueous solution and colloidal silica (SiO ₂ ) suspension (Ba (NO ₃ ) ₂ , Ca (NO ₃ ) ₂ , Mg (
The molar ratio of NO ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, Mn (NO ₃ ) ₂ · 6H ₂ O, SiO ₂ is 0.88: 0.44: 0.44: 0. _0.2 : 0.04: 1) was used in the same manner as in Example 1 except that phosphor Ba _0.88 Ca _0.44 Mg _0.44 Eu _0.2 Mn _0.04 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. It can be seen that when the amount of Ca is half the amount of Ba in the crystal, the peak wavelength of the red component is less than 615 nm, and colorful white light cannot be emitted.

(Comparative Example 10)
Ba (NO ₃ ) ₂ aqueous solution, Ca (NO ₃ ) ₂ .4H ₂ O aqueous solution, Mg (NO ₃ ) ₂ .6H ₂ O aqueous solution, Eu (NO ₃ ) ₃ .6H ₂ O aqueous solution, Mn ( NO ₃ ) ₂ · 6H ₂ O aqueous solution and colloidal silica (SiO ₂ ) suspension (Ba (NO ₃ ) ₂ , Ca (NO ₃ ) ₂ , Mg (
The molar ratio of NO ₃ ) ₂ · 6H ₂ O, Eu (NO ₃ ) ₃ · 6H ₂ O, Mn (NO ₃ ) ₂ · 6H ₂ O, SiO ₂ is 1.144: 0.216: 0.48: 0. .01: 0.15: 1) was used in the same manner as in Example 1 except that white phosphor phosphor Ba _1.144 Ca _0.216 Mg _0.48 Eu _0.01 Mn _0.15 SiO ₄ was produced. The emission spectrum was measured when this phosphor was excited at 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. Table 2 shows the wavelength and relative intensity of the peak of the red component, the wavelength and relative intensity of the maximum peak of less than 590 nm, the half width of the peak group, and the x value and y value of the chromaticity coordinates. It can be seen that when the Eu molar ratio is as small as 0.01 in the crystal, the intensity of the red component is slightly reduced.

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 type 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 (350-430 nm light-emitting body). The typical sectional view showing an example of the surface emitting illumination device of the present invention. The emission spectrum of the phosphor of Example 3 when irradiated with light having a wavelength of 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. The emission spectrum of the phosphor of Example 4 when irradiated with light having a wavelength of 400 nm, which is the dominant wavelength in the ultraviolet region of a GaN-based light emitting diode. The figure showing the method of measuring the half value width of a peak group.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 2nd light-emitting body 2 Surface emitting GaN-type LD
3 Substrate 4 Light emitting device 5 Mount lead 6 Inner lead 7 First light emitter (light emitter of 350 to 430 nm)
DESCRIPTION OF SYMBOLS 8 Resin part containing fluorescent substance in the present invention 9 Conductive wire 10 Mold member 11 Surface emitting illumination device incorporating light emitting element 12 Holding case 13 Light emitting device 14 Diffusion plate

Claims (8)

A phosphor having a crystal phase having a chemical composition represented by the following general formula [1].

(However, M ¹ is at least one element selected from the group of divalent elements other than monovalent elements, Eu, Mn, and Mg, trivalent elements, and pentavalent elements. The proportion of the element is 80 mol% or more, the proportion of the total of Ba, Ca, and Sr is 40 mol% or more, and the proportion (molar ratio) of Ca to the sum of Ba and Ca is less than 0.2. ² represents a tetravalent element group containing 90 mol% or more of Si and Ge in total, and Z is at least one element selected from the group consisting of −1 and −2 elements, H and N. A is 0.0003 ≦ a ≦ 0.8, b is 0 <b ≦ 0.8, c and d are 0 <c / (c + d) ≦ 0.2, or 0.3 ≦ c / (c + d) ≦ 0.8, a, b, c, d are 1.8 ≦ (a + b + c + d) ≦ 2.2, and e, f are 0 ≦ f / (e + f) ≦ 0.03. 5 and 3.6 ≦ (e + f) ≦ 4.4.) The phosphor according to claim 1, wherein a ratio of the total of Ba, Ca, and Sr in M ¹ is 80 mol% or more. The phosphor according to 1 or 2, wherein the proportion of Si in M ² is 80 mol% or more. A phosphor having a crystal phase having the chemical composition of the general formula [1].
(However, M ¹ is at least one element selected from the group of divalent elements other than monovalent elements, Eu, Mn, and Mg, trivalent elements, and pentavalent elements. The proportion of the element is 80 mol% or more, the proportion of the total of Ba, Ca, and Sr is 40 mol% or more, and the proportion (molar ratio) of Ca to the sum of Ba and Ca is less than 0.2. ² represents a tetravalent element group containing 90 mol% or more of Si and Ge in total, and Z is at least one element selected from the group consisting of −1 and −2 elements, H and N. A is 0.01 <a ≦ 0.5, b is 0 <b ≦ 0.8, c and d are 0 <c / (c + d) ≦ 0.2, or 0.3 ≦ c / (c + d) ≦ 0.7, a, b, c, d are 1.9 ≦ (a + b + c + d) ≦ 2.1, e, f are 0 ≦ f / (e + f) ≦ 0.01, And 3.8 ≦ (e + f) ≦ 4.2.) In a light-emitting device including a first light-emitting body that generates light of 350 to 430 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 4. 6. The light emitting device according to claim 5, wherein the first light emitter is a laser diode or a light emitting diode. A lighting device comprising the light emitting device according to claim 5. An image display device comprising the light emitting device according to claim 5.

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