JP2015067754A - Composite wavelength conversion particle, resin composition containing composite wavelength conversion particle, and light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite wavelength conversion particle that has high use efficiency of light and high use efficiency of a phosphor itself, can achieve both high efficiency light emission and high reliability, and is environmentally friendly, and to provide an organic resin composition containing composite wavelength conversion particles, and a light-emitting device.SOLUTION: A composite wavelength conversion particle 1 contains an yttrium aluminum garnet phosphor 3 dispersed in a fluoride matrix particle 2 comprising one or more compounds selected from the group consisting of magnesium fluoride, calcium fluoride and strontium fluoride; and the particle shows a maximum of emission intensity in a wavelength region of 560 nm or more and 580 nm or less.

Description

  The present invention relates to a composite wavelength conversion particle, a composite wavelength conversion particle-containing resin composition, and a light emitting device. More specifically, the light utilization efficiency and the phosphor utilization efficiency are high, and both high efficiency light emission and high reliability are achieved. The present invention relates to a composite wavelength conversion particle, a composite wavelength conversion particle-containing resin composition, and a light emitting device.

  Phosphors are used in various optical devices such as various display devices, lighting devices, solar power generation devices, photonic devices, and optical amplifiers. In particular, phosphors used for wavelength conversion films of photovoltaic devices such as white light emitting elements (white LED elements) and solar cells are relatively low energy electron beams such as near ultraviolet rays or blue light among visible rays. It is necessary to emit light (fluorescence) with high efficiency by excitation. In addition, white light-emitting elements and photovoltaic devices have excellent phosphor long-term stability (small degradation over a long period of time), as well as reduced luminous efficiency even at high temperatures and high humidity. Small wavelength conversion materials are needed. In particular, in optical devices using wavelength conversion materials that are excited by near ultraviolet rays or visible rays to emit visible rays or infrared rays, it is necessary to achieve both high efficiency of light emission, high reliability, and excellent durability. It is said that.

A YAG phosphor having a garnet structure such as yttrium aluminum garnet (YAG) is generally used as such a phosphor material, that is, a phosphor material that is excited by near ultraviolet light or blue light and emits visible light with high efficiency. It has been. For example, Y ₃ Al ₅ O ₁₂ : Ce ³⁺ , which is an example, has a quantum efficiency of about 90% at room temperature.
Further, as phosphor materials other than this YAG-based phosphor, particulate phosphor materials such as silicate, borate, and phosphate have been developed and proposed. It is inferior to YAG phosphors in terms of moisture resistance and heat resistance.
Further, nitride and oxynitride phosphor materials have been proposed as phosphor materials having the same luminous efficiency and durability as YAG phosphors.

These phosphor materials are generally used as a wavelength conversion member dispersed in an organic binder such as epoxy resin or silicone resin or glass or silica-based inorganic binder in the form of particles.
In this wavelength conversion member, the refractive index of the phosphor material is about 1.63 to 2.0, but the refractive index of the organic binder or the inorganic binder is smaller than 1.6. Scattering occurs due to the difference in refractive index from the binder. For example, in an optical element in which excitation light from a light source is incident from behind a wavelength conversion member and emitted light is emitted in front of the wavelength conversion member, it is necessary to reduce light loss due to backscattering. Therefore, the particle diameter of the phosphor is set to about 10 μm.

By the way, in the case of phosphor particles having a particle size of about 10 μm, excitation light is absorbed and emitted light is emitted only on the surface layer of the particles, and the inside of the particles almost functions as a phosphor. Many parts of the phosphor particles are wasted.
Therefore, in order to improve the light utilization efficiency by light scattering of the phosphor particles, phosphor particles in which the surface of the phosphor particles is covered with a porous coating layer made of a metal oxide have been proposed (Patent Document 1). ).
In addition, a phosphor material in which the loss of light utilization efficiency due to light scattering is reduced by dispersing phosphor particles having a particle diameter smaller than the wavelength of excitation light or radiation light in a binder has been proposed. For example, a luminescent material in which a rare earth metal for an emission center is supported on a zeolite single crystal (Patent Document 2), a monodispersed spherical inorganic phosphor in which oxide phosphor nanoparticles are dispersed in a spherical silica matrix (Patent Document 3), etc. Has been proposed.
Furthermore, an attempt to suppress light scattering by reducing the particle size of the YAG phosphor has been proposed.

Special table 2011-503266 gazette JP 2003-246981 A JP 2010-155958 A

However, in the phosphor particles described in Patent Document 1, the surface of the phosphor particles is covered with a porous coating layer made of a metal oxide, thereby suppressing scattering on the surface of the phosphor particles. Although it can be done, it does not improve the refractive index of the phosphor particles themselves, so there is a problem that there is almost no effect of suppressing light scattering.
In addition, in the luminescent material described in Patent Document 2, since the rare earth metal for the luminescent center is supported on the zeolite single crystal, the loss of light utilization efficiency due to light scattering is reduced, but the luminous efficiency due to the surface defects of the luminescent material itself. There was a problem of a significant drop. Furthermore, it is easily affected by humidity and its performance as a wavelength conversion material is insufficient.

Further, in the monodispersed spherical inorganic phosphor described in Patent Document 3, the oxide phosphor nanoparticles are dispersed in the spherical silica matrix, so that the loss of light utilization efficiency due to light scattering is reduced, but the monodispersed There has been a problem that the luminous efficiency due to surface defects of the spherical inorganic phosphor itself is greatly reduced. Furthermore, it is easily affected by humidity and its performance as a wavelength conversion material is insufficient.
Further, in the case where the light scattering is suppressed by reducing the particle diameter of the YAG phosphor, the influence of crystal disturbance on the surface of the YAG phosphor particles is greatly affected by reducing the particle diameter. Therefore, the luminous efficiency was as low as about 21 to 56%, which was insufficient practically.

  The present invention has been made in view of the above circumstances, and has high light use efficiency and high use efficiency of the phosphor itself, and can achieve both high efficiency light emission and high reliability. An object of the present invention is to provide a composite wavelength conversion particle, a composite wavelength conversion particle-containing resin composition, and a light-emitting device that are gentle to the environment.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors are made of a fluoride containing one or more selected from the group consisting of magnesium fluoride, calcium fluoride and strontium fluoride. If the yttrium aluminum garnet phosphor is dispersed in the matrix particles and the maximum emission intensity is in the wavelength region of 560 nm or more and 580 nm or less, the light utilization efficiency and the phosphor utilization efficiency can be improved. It has been found that it is possible to achieve both high-efficiency light emission and high reliability, and that it is friendly to the global environment, and the present invention has been completed.

  That is, the composite wavelength conversion particle of the present invention includes yttrium aluminum in matrix particles made of fluoride containing one or more selected from the group of magnesium fluoride, calcium fluoride and strontium fluoride. A garnet phosphor is dispersed, and the maximum value of emission intensity is in a wavelength region of 560 nm or more and 580 nm or less.

The yttrium aluminum garnet phosphor is
_{(Y 3-x-z Ce} x M z) (Al 5-y-w R w Si y) O 12 ...... (1)
(However, M is at least one of lanthanoid and Bi excluding Ce, R is at least one of In and Ga, and 0.21 ≦ x ≦ 0.9, 0 ≦ y ≦ 1.5, 0 ≦ z ≦ 1.5, 0 ≦ w ≦ 1.0)
Is preferably the main component.
The mass percentage of the yttrium aluminum garnet phosphor with respect to the fluoride is preferably 20% by mass or more and 70% by mass or less.

  The composite wavelength conversion particle-containing resin composition of the present invention is characterized in that the composite wavelength conversion particles of the present invention are dispersed in a resin.

  A light-emitting device of the present invention includes a semiconductor light-emitting element that emits light in a wavelength region of 300 nm or more and 500 nm or less, and a light-emitting layer that emits visible light by receiving light emitted from the semiconductor light-emitting element. The light emitting layer contains the composite wavelength conversion particle according to any one of claims 1 to 3.

  The light emitting layer preferably contains one or more of a yellow phosphor, a blue phosphor, a green phosphor and a red phosphor.

  According to the composite wavelength conversion particle of the present invention, the yttrium aluminum garnet is contained in the matrix particle made of fluoride containing one or more selected from the group of magnesium fluoride, calcium fluoride and strontium fluoride. System phosphors are dispersed, and the maximum value of the emission intensity is in the wavelength region of 560 nm or more and 580 nm or less, so that the light utilization efficiency and the utilization efficiency of the particles themselves can be increased. Can emit light. In addition, since this high-efficiency light emission is stable over a long period of time, the reliability can be improved.

Furthermore, since the yttrium aluminum garnet phosphor is dispersed in the matrix particles having a high coefficient of thermal expansion, it is possible to generate a large compressive stress in the matrix particles and distort the crystal structure of the yttrium aluminum garnet phosphor. Therefore, the emission wavelength can be increased.
As described above, both high-efficiency light emission and high reliability can be achieved.

  According to the composite wavelength conversion particle-containing resin composition of the present invention, since the composite wavelength conversion particles of the present invention are dispersed in the resin, the light utilization efficiency and the utilization efficiency of the resin composition itself can be increased. Light can be emitted with high efficiency. In addition, since this high-efficiency light emission is stable over a long period of time, the reliability can be improved.

  According to the light emitting device of the present invention, a semiconductor light emitting element that emits light in a wavelength region of 300 nm or more and 500 nm or less, a light emitting layer that emits visible light by receiving light emitted from the semiconductor light emitting element, This light emitting layer contains the composite wavelength conversion particles of the present invention, so that the light utilization efficiency and the utilization efficiency of the resin composition itself can be increased, and therefore, the light emission layer can be made to emit light with high efficiency. Reliability can be improved over a long period of time.

It is sectional drawing which shows the composite wavelength conversion particle of one Embodiment of this invention. It is sectional drawing which shows the surface mount type light-emitting device which is an example of the light-emitting device of one Embodiment of this invention. It is sectional drawing which shows the surface mount type light-emitting device which is another example of the light-emitting device of one Embodiment of this invention. It is sectional drawing which shows the surface mount type light-emitting device which is another example of the light-emitting device of one Embodiment of this invention. It is a scanning electron microscope (SEM) image which shows the composite wavelength conversion particle | grains of Example 1 of this invention. It is an expansion scanning electron microscope (SEM) image which shows the composite wavelength conversion particle of Example 1 of this invention. It is a figure which shows the X-ray absorption edge vicinity fine structure spectrum of Ce-L3 absorption edge of the composite wavelength conversion particle of Example 7 of this invention. It is a figure which shows the distance between ions in each composite wavelength conversion particle of Example 7, 8, 10 of this invention.

The form for implementing the composite wavelength conversion particle | grains of this invention, the composite wavelength conversion particle containing resin composition, and a light-emitting device is demonstrated.
The following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified.

[Composite wavelength conversion particles]
FIG. 1 is a cross-sectional view showing a composite wavelength conversion particle according to an embodiment of the present invention. The composite wavelength conversion particle 1 is selected from the group consisting of magnesium fluoride, calcium fluoride and strontium fluoride. An yttrium aluminum garnet phosphor 3 is dispersed in matrix particles 2 made of a fluoride containing two or more kinds.
The maximum value of the emission intensity of the composite wavelength conversion particle 1 is in the wavelength region of 560 nm or more and 580 nm or less.
Next, the composite wavelength conversion particles will be described in detail.

"Matrix particles"
Matrix particles are a particulate material that constitutes the base portion of the composite wavelength conversion particle, and are composed of fluoride.
As this fluoride, a fluoride having a refractive index lower than that of the yttrium aluminum garnet phosphor and excellent in durability such as heat resistance and chemical resistance, that is, magnesium fluoride (refractive index: 1.38), One or more selected from the group of calcium fluoride (refractive index: 1.43) and strontium fluoride (refractive index: 1.44) are preferably used.
These fluorides can be used in combination with amorphous silica (refractive index: 1.45).

The average particle diameter of the matrix particles is preferably 1 nm or more and 500 nm or less, more preferably 10 nm or more and 300 nm or less, or the length of the excitation wavelength or less.
Here, when the average particle diameter of the matrix particles exceeds 500 nm, Mei scattering occurs due to the refractive index difference between the fluorides and the phosphor particles constituting the matrix particles, and the use efficiency of the excitation light decreases. This is not preferable.
On the other hand, if the average particle size of the matrix particles is less than 1 nm, the chemical resistance and water resistance are lowered, which is not preferable.

The matrix particles are formed by combining a plurality of fluoride crystallites containing one or more selected from the group consisting of magnesium fluoride, calcium fluoride, and strontium fluoride. It has become.
Moreover, the crystallite diameter of the fluoride in the matrix particles can be measured using an X-ray diffraction method.

The average crystallite diameter of the fluoride is preferably 100 nm or less, and more preferably 80 nm or less.
Here, when the average crystallite diameter of the fluoride exceeds 100 nm, the dispersed state of the phosphor particles becomes non-uniform, and the forward light emission property is lowered, which is not preferable.

The matrix particles can be produced using a known method. For example, when producing fine particles made of fluoride, a fluoride containing an aqueous solution of ammonium fluoride and one or more fluorides selected from the group of magnesium fluoride, calcium fluoride and strontium fluoride By mixing the aqueous solution, fluoride fine particles composed of one kind or two or more kinds selected from the group of magnesium fluoride fine particles, calcium fluoride fine particles and strontium fluoride fine particles can be produced in a colloidal form.
Therefore, fluoride fine particles composed of one or more selected from the group of magnesium fluoride fine particles, calcium fluoride fine particles and strontium fluoride fine particles can be easily produced using a simple apparatus.

"Yttrium aluminum garnet phosphor"
Yttrium aluminum garnet phosphor (hereinafter sometimes abbreviated as YAG phosphor)
_{(Y 3-x-z Ce} x M z) (Al 5-y-w R w Si y) O 12 ...... (2)
(However, M is at least one of lanthanoid and Bi excluding Ce, R is at least one of In and Ga, and 0.21 ≦ x ≦ 0.9, 0 ≦ y ≦ 1.5, 0 ≦ z ≦ 1.5, 0 ≦ w ≦ 1.0)
Is a phosphor that emits yellowish fluorescence.

Here, the crystal structure and emission wavelength of the YAG phosphor will be described.
YAG-based phosphors have a garnet structure (composition formula: II ₃ III ₂ IV ₃ O ₁₂ , where II, III, and IV are divalent, trivalent, and tetravalent metal ions, respectively), and oxygen 6-coordinated Oxygen 8-coordinated metal ions (II) are arranged in distorted voids in the network of metal ions (III) and oxygen 4-coordinated metal ions (IV).
For example, yttrium aluminum garnet (YAG) has a structure in which yttrium ions are arranged at oxygen 8-coordinate positions and aluminum ions are arranged at oxygen 4-coordinate positions and 6-coordinate positions.

On the other hand, in a YAG phosphor, 5d of cerium ions affected by surrounding oxygen ions is obtained by substituting cerium (III) ions for a part of yttrium ions at the oxygen 8-coordinate positions arranged in the distorted voids. It is known that crystal field splitting occurs in the orbit, and light emission in the visible light region due to the 4f-5d transition of cerium (III) ions is used.
Conventionally, as a method of controlling the emission wavelength of a YAG phosphor, ions such as cadmium ions and gallium ions having ion radii different from yttrium ions, aluminum ions, cerium ions at oxygen 8-coordinate positions and oxygen 4-coordinate positions are used. Is used to control the size of the crystal field splitting of the cerium ion at the 8-coordinate position by distorting the 8-coordinate structure.

The method for controlling the emission wavelength of the YAG phosphor of the present embodiment is completely different from the method for controlling the garnet structure by adding ion species having different ionic radii as described above.
That is, the YAG phosphor is fixed by matrix particles having a higher thermal expansion coefficient than that of the YAG phosphor and a low refractive index, so that the YAG phosphor is compressed by the difference in thermal expansion force inside the particles. In this method, stress is generated, and thus the garnet structure is deformed and distorted, and as a result, the emission wavelength of the YAG phosphor can be controlled.
In this case, for example, when the thermal expansion coefficient of the fluoride is about 24 ppm, the thermal expansion coefficient of the YAG phosphor is about 8 ppm.

As a result, the YAG phosphor of this embodiment can increase the crystal field splitting of cerium ions without using rare metal ions such as gadmium ions and gallium ions. As a result, high luminous efficiency can be obtained. Can be achieved. In addition, even if the concentration of the cerium ion to be added is set to a high concentration that has not been known in the past, so-called “concentration quenching” due to luminescent ions does not occur.
As described above, by adding cerium ions to the YAG-based phosphor at a high concentration, it is possible to achieve both a longer emission peak wavelength and higher emission efficiency.

  In the YAG-based phosphor represented by the above formula (2), M (ion) is a metal element other than yttrium (Y) and has a larger ionic radius (r) in 8-coordinate than Y. Ions, that is, ions composed of at least one of lanthanoid and bismuth (Bi: r = 1.17) excluding Ce are preferable.

  Here, the lanthanoid in which M (ion) excludes Ce means that M is an ion excluding cerium (Ce) among rare earth elements having atomic numbers of 57 to 71, and lanthanum (La: r = 1. 16), praseodymium (Pr: r = 1.13), neodymium (Nd: r = 1.12), promethium (Pm), samarium (Sm: r = 1.08), europium (Eu: r = 1.07) ), Gadolinium (Gd: r = 1.05), terbium (Tb: r = 1.04), dysprosium (Dy: r = 1.03), holmium (Ho), erbium (Er: r = 1.00) , Thulium (Tm), ytterbium (Yb), and lutetium (Lu: r = 0.97).

  In the above equation (2), the reason why the value range of x is 0.21 ≦ x ≦ 0.9 is that when x <0.21, the emission wavelength peak is smaller than 560 nm and the emission color is shifted to green. This is not preferable. On the other hand, when x> 0.9, even if more cerium ions are added, the emission wavelength peak does not change, which is not preferable.

R (ion) is a metal element other than the tetracoordinated aluminum ion (r = 0.39), and is a trivalent having an ionic radius larger than that of the tetracoordinated aluminum ion. Examples include metal element ions such as indium (In: r = 0.62) and gallium (Ga: r = 0.47).
In the above formula (2), the reason why the range of the value of w is 0 ≦ w ≦ 1.0 is that when w> 1.0, the light emission efficiency is remarkably deteriorated, which is not preferable.

The average particle size of this YAG phosphor is preferably 1 nm or more and 500 nm or less, more preferably 20 nm or more and 300 nm or less, like the average particle size of the matrix particles.
Here, the reason why the average particle diameter of the YAG phosphor is set to the above range is that this range is a range in which the refractive index of the YAG phosphor is 1.6 or more and 2.0 or less. .

  Here, when the average particle diameter of the YAG phosphor exceeds 500 nm, Mei scattering occurs due to the refractive index difference between the YAG phosphor and the matrix particles. Backscattering is increased, and the YAG phosphor is dispersed in the resin to form a resin composition, which reduces the light emission efficiency, which is not preferable. On the other hand, if the average particle diameter of the YAG phosphor is less than 1 nm, the light absorption efficiency of the YAG phosphor is lowered, which is not preferable.

The crystallite diameter of this YAG phosphor can be measured using an X-ray diffraction method.
The average crystallite size of this YAG phosphor is preferably 200 nm or less, and more preferably 150 nm or less.
Here, if the average crystallite diameter of the YAG phosphor exceeds 200 nm, the dispersibility of the YAG phosphor in the matrix particles becomes non-uniform, and the forward light emission is reduced, which is not preferable.
This YAG phosphor can be synthesized by a usual solid phase method, sol-gel method, coprecipitation method, uniform precipitation method, solvothermal method, combustion method, complex polymerization method, and the like.

"Composite wavelength conversion particles"
The composite wavelength conversion particle of the present embodiment is present in a state where the YAG phosphor is dispersed in matrix particles composed of particles having a refractive index lower than that of the YAG phosphor.
That is, it is a composite structure of the above YAG phosphor and matrix particles made of a substance having a refractive index lower than that of the YAG phosphor.

In this composite wavelength conversion particle, the YAG phosphor is a matrix particle made of a fluoride containing one or more selected from the group of dense calcium fluoride and strontium fluoride constituting the matrix particle. Since the structure is held inside, most of the YAG phosphors are not in contact with the external atmosphere (air, water vapor, etc.) except for the YAG phosphors present on the surface of the composite wavelength conversion particles. Can do.
Since the composite wavelength conversion particles are usually used as a resin composite by mixing with a resin, the shape is preferably spherical.

  In the composite wavelength conversion particle of this embodiment, the refractive index is about 1 in the matrix particles made of fluoride containing one or more selected from the group of magnesium fluoride, calcium fluoride and strontium fluoride. .8 is dispersed, the refractive index of the entire composite wavelength conversion particle can be controlled to a desired refractive index, for example, 1.6 or less.

Further, the refractive index of the composite wavelength conversion particle is such that the fluoride containing one or more selected from the group consisting of magnesium fluoride, calcium fluoride and strontium fluoride constituting the matrix particle, and YAG fluorescence It can be controlled by changing the ratio to the body, that is, the ratio (M _F : M _Y ) of the mass of the fluoride (M _F ) and the mass of the YAG phosphor (M _Y ).
For example, in order to reduce the refractive index of the entire composite wavelength conversion particle to 1.6 or less, the refractive index of the matrix particle is set to 1.45 or less, although it depends on the refractive index and amount of the YAG phosphor. Is more preferable because more YAG phosphors can be contained.

The content of the YAG phosphor in the composite wavelength conversion particle is preferably 20% by mass or more and 70% by mass or less, more preferably 20% by mass or more and 60% by mass or less, with respect to the total mass of the composite wavelength conversion particle. It is.
Here, when the content of the YAG phosphor is less than 20% by mass, the compressive stress due to the difference in thermal expansion coefficient between the matrix particles made of fluoride and the YAG phosphor acts on the YAG phosphor evenly. Therefore, the YAG crystal structure cannot be deformed or distorted, and as a result, the luminous efficiency is not improved, which is not preferable. On the other hand, when the content exceeds 70% by mass, the compressive stress due to the matrix particles composed of fluoride is reduced, and as a result, the YAG-based phosphor is present alone, and the luminous efficiency is lowered. The number of YAG phosphors exposed on the surface of the composite wavelength conversion particles increases, and the exposed YAG phosphors are affected by the external atmosphere, and the durability and characteristics are deteriorated. .

  The average particle diameter of the composite wavelength conversion particles is not particularly limited. However, when preparing a resin composite by mixing with various resins, the ease of mixing with various resins and the preparation of the resin composite are not limited. In terms of ease, a range of 1 μm or more and 50 μm or less is preferable.

The composite wavelength conversion particles include fluoride particles containing one or more selected from the group of magnesium fluoride, calcium fluoride, and strontium fluoride having an average particle diameter of 500 nm or less, and the YAG-based fluorescence described above. A precursor of the body, and the precursor is uniformly dispersed between the fluoride particles, and the resulting mixture is subjected to heat treatment at a temperature range equal to or higher than a temperature at which the YAG phosphor is generated and crystallized, It can be obtained by producing a YAG-based phosphor between the fluoride particles and then performing a heat treatment or a thermal reduction treatment at a temperature below the melting point of the fluoride particles.
It is not preferable that the heat treatment temperature or the heat reduction treatment temperature is equal to or higher than the melting point of the fluoride particles because both the YAG phosphor and the fluoride particles grow and become coarse.

  In the composite wavelength conversion particle of this embodiment, a YAG-based phosphor having a refractive index of about 1.8 and an average particle diameter of about the excitation / radiation wavelength or less is dense, low refraction with high chemical and thermal stability. According to the effective medium theory, the refractive index of such composite wavelength conversion particles is determined by the volume of the fluoride particles and the YAG phosphor. The refractive index is expressed by a fraction.

Therefore, when the composite wavelength conversion particles are dispersed in the binder, the difference in refractive index between the composite wavelength conversion particles and the binder can be reduced. Therefore, the light use efficiency can be increased. That is, it becomes possible to radiate green light excited and emitted by excitation light having a wavelength of 300 to 500 nm emitted from a light source (semiconductor element) in a more forward direction (advancing direction of excitation light). At the same time, 300 to 500 nm ultraviolet light or blue light emitted from a light source (semiconductor element) can be irradiated in the forward direction, so that a light emitting device with excellent luminous efficiency can be manufactured.
In addition, the utilization efficiency of the YAG phosphor is maximized, and furthermore, since the YAG phosphor is embedded in a dispersed state in a dense matrix, high reliability can be ensured.

[Composite wavelength conversion particle-containing resin composition]
The composite wavelength conversion particle-containing resin composition of this embodiment is a resin composition obtained by dispersing the composite wavelength conversion particles of this embodiment in a resin.
In this resin composition, the refractive index of the composite wavelength conversion particle is 1 in order to reduce the difference in refractive index between the composite wavelength conversion particle and the resin to suppress backscattering and improve the light utilization efficiency. .6 or less is preferable.

The resin is not particularly limited as long as it is transparent to the target wavelength band of light, and is a thermoplastic resin, thermosetting resin, light (electromagnetic wave) curing that is cured by visible light, ultraviolet light, infrared light, or the like. A curable resin such as a curable resin or an electron beam curable resin that is cured by electron beam irradiation is preferably used.
Examples of such resins include epoxy resins, silicone resins, acrylic resins, polyester resins, fluorine resins, polyethylene resins, polypropylene resins, polystyrene resins, nylon resins, polyacetal resins, polyethylene terephthalate resins, polyimide resins, liquid crystal polymers, poly Examples include ether sulfone resin, polysulfone resin, polycarbonate resin, butyral resin. In particular, a silicone resin is preferable because it is excellent in heat resistance and light resistance and has high affinity with the composite wavelength conversion particles.

Examples of such silicone resins include dimethyl silicone resin, methylphenyl silicone resin, diphenyl silicone resin, vinyl group-containing silicone resin, amino group-containing silicone resin, methacryl group-containing silicone resin, carboxy group-containing silicone resin, and epoxy group-containing. Silicone resin, carbinol group-containing silicone resin, phenyl group-containing silicone resin, organohydrogen silicone resin, alicyclic epoxy group-modified silicone resin, polycyclic hydrocarbon-containing silicone resin, aromatic ring hydrocarbon-containing silicone resin, etc. It is done.
These silicone resins are usually used alone, but two or more kinds of silicone resins can be used in combination depending on applications.

[Light emitting device]
FIG. 2 is a cross-sectional view showing a surface-mounted light-emitting device that is an example of a light-emitting device according to an embodiment of the present invention. The surface-mounted light-emitting device 11 is 300 nm in a recess 13 of a frame 12 made of an insulator. The semiconductor light emitting element 14 that emits light in the wavelength region of 500 nm or less is provided, and the light emitting layer 15 is provided on the outgoing light side of the semiconductor light emitting element 14.
Electrodes 16 and 17 are embedded in the recess 13, and the semiconductor light emitting element 14 is electrically connected to the electrode 16, and is further electrically connected to the electrode 17 by a bonding wire 18.
In the light emitting layer 15, the composite wavelength conversion particle 22, the green phosphor 23, and the red phosphor 24 of the present embodiment are dispersed in a resin 21 having transparency.

In this surface-mounted light-emitting device 11, the semiconductor light-emitting element 14 emits light in a wavelength region of 300 nm or more and 500 nm or less, and the composite wavelength conversion particle 22 receives this light.
In this composite wavelength conversion particle 22, the wavelength of the received light (300 nm or more and 500 nm or less) is lengthened, and emits yellow light in a wavelength region in which the emission peak is 560 nm or more and 580 nm or less.
On the other hand, the green phosphor 23 and the red phosphor 24 receive light emitted from the semiconductor light emitting element 14, the green phosphor 23 emits green light in a specific wavelength region, and the red phosphor 24 has a specific wavelength. Emits red light in the area.
Therefore, the light emitted from the surface-mount light-emitting device 11 is recognized as white light by superimposing yellow light, green light, and red light.

  FIG. 3 is a cross-sectional view showing a surface-mounted light-emitting device that is another example of the light-emitting device according to the embodiment of the present invention. The surface-mounted light-emitting device 31 is different from the surface-mounted light-emitting device 11 described above. The point is that the composite wavelength conversion particle-containing resin layer 32 in which the composite wavelength conversion particle 22 of the present embodiment is dispersed is formed on the side of the resin 21 having transparency close to the semiconductor light emitting element 14. A phosphor-containing resin layer 33 in which a green phosphor 23, a red phosphor 24, and, if necessary, a yellow phosphor (not shown) are dispersed is formed on the containing resin layer 32, and these composite wavelength conversion particle-containing resins. The light emitting layer 34 having a two-layer structure is configured by the layer 32 and the phosphor-containing resin layer 33.

In the surface mount light emitting device 31, the semiconductor light emitting element 14 emits light in a wavelength region of 300 nm or more and 500 nm or less, and the composite wavelength conversion particle 22 in the composite wavelength conversion particle-containing resin layer 32 receives this light. .
In this composite wavelength conversion particle 22, the wavelength of the received light (300 nm or more and 500 nm or less) is lengthened, and emits yellow light in a wavelength region in which the emission peak is 560 nm or more and 580 nm or less.
On the other hand, in the phosphor-containing resin layer 33, the light emitted from the semiconductor light emitting element 14 is received by the green phosphor 23, the red phosphor 24 and, if necessary, the yellow phosphor (not shown). The green phosphor emits green light of a specific wavelength region, the red phosphor 24 emits red light of a specific wavelength region, and the yellow phosphor emits yellow light of a specific wavelength region.
Therefore, the light emitted from the surface mount light emitting device 31 is recognized as white light by superimposing yellow light, green light, and red light.

  FIG. 4 is a cross-sectional view illustrating a surface-mounted light-emitting device that is still another example of the light-emitting device according to the embodiment of the present invention. The surface-mounted light-emitting device 41 includes the surface-mounted light-emitting device 11 described above. 31 is different from the resin 21 having the same or different composition as the resin 21 on the transparent resin 21 filled in the recess 13, and the composite wavelength conversion particle 22 and the green phosphor of the present embodiment. 23 and the light emitting layer 43 in which the red phosphor 24 is dispersed.

In the surface mount light emitting device 41, the semiconductor light emitting element 14 emits light in a wavelength region of 300 nm or more and 500 nm or less, and the composite wavelength conversion particle 22 in the light emitting layer 43 receives this light.
In this composite wavelength conversion particle 22, the wavelength of the received light (300 nm or more and 500 nm or less) is lengthened, and emits yellow light in a wavelength region in which the emission peak is 560 nm or more and 580 nm or less.
On the other hand, the green phosphor 23 and the red phosphor 24 receive light emitted from the semiconductor light emitting element 14, the green phosphor 23 emits green light in a specific wavelength region, and the red phosphor 24 has a unique wavelength region. The red light is emitted.
Therefore, the light emitted from the surface-mounted light emitting device 41 is recognized as white light by superimposing yellow light, green light, and red light.
Next, the components of these surface mount light emitting devices 11, 31, 41 will be described in detail.

"Semiconductor light emitting device"
The semiconductor light-emitting element 14 emits light that excites the light-emitting layers 15, 34, and 43, and the emission wavelength is not particularly limited as long as it overlaps with the absorption wavelength of the light-emitting layers 15, 34, and 43. In addition, a wide emission wavelength region can be used. Usually, it is preferable to use an emission wavelength from the ultraviolet region to the blue region, particularly an emission wavelength from 300 nm to 500 nm from the near ultraviolet region to the blue region.

The semiconductor light emitting element 14 is preferably a GaN LED (light-emitting diode) or LD (laser diode) using a GaN compound semiconductor.
The reason is that 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 low when combined with the light-emitting layers 15, 34, and 43. This is because very bright light emission can be obtained with electric power.

For example, GaN-based LEDs and LDs have a light emission intensity that is 100 times or more compared to SiC-based LEDs with respect to a current load of 20 mA.
In GaN-based LEDs and LDs, an Al _x Ga _y N light emitting layer (x + y = 0.8 to 1.2), a GaN light emitting layer, and an In _x Ga _y N light emitting layer (x + y = 0.8 to 1.2) are provided. What it has is preferable because the emission intensity is high. Among these, those having an In _x Ga _y N light emitting layer (x + y = 0.8 to 1.2) are preferable because the light emission intensity is very strong.

A GaN-based LED is a light emitting layer such as an Al _x Ga _y N light emitting layer (x + y = 0.8 to 1.2), a GaN light emitting layer, an In _x Ga _y N light emitting layer (x + y = 0.8 to 1.2), or the like. , P layer, n layer, electrode, and substrate, and the above light emitting layer is made of n-type and p-type Al _x Ga _y N layers (x + y = 0.8 to 1). .2), a hetero structure sandwiched by Ga _y N layers (y = 0.8 to 1.2), GaN layers, In _x Ga _y N layers (x + y = 0.8 to 1.2), etc. In particular, in a GaN-based LED, a multi-quantum well structure including an In _x Ga _y N light emitting layer and a GaN layer is particularly preferable because the light emission intensity is very strong.

In the GaN-based LED, those in which these light emitting layers are doped with Zn or Si or those without dopants are preferable for adjusting the light emission characteristics.
Only one semiconductor light emitting element 14 may be used, or two or more semiconductor light emitting elements 14 may be used in combination.

"Light emitting layer"
The light-emitting layer emits visible light by receiving light emitted from the semiconductor light-emitting element 14 and contains the composite wavelength conversion particles of the present embodiment, as well as a green phosphor and a red phosphor, as necessary. Yellow phosphor (not shown).
This light emitting layer is provided on the optical path of the light emitted from the semiconductor light emitting element 14.

In particular, when the red phosphor layer and the green phosphor layer are overlaid on the light emitting layer 15, when the light emitted from the semiconductor light emitting element 14 is blue light, the light emitting layer 15 is changed to the red phosphor layer and the green phosphor layer. It is more preferable to provide the phosphor layer closer to the semiconductor light emitting element 14 than the phosphor layer because the light emission efficiency is increased.
Here, in the composite wavelength conversion particle 22 of the present embodiment, the light emitted from the semiconductor light emitting element 14 is absorbed and the light that is not absorbed (blue light) is not backscattered and absorbed by the composite wavelength conversion particle 22. It proceeds in the traveling direction of the light emitted from the semiconductor light emitting element 14 to excite more red and green phosphor layers.
As described above, by arranging the light emitting layer 15, the green phosphor layer, and the red phosphor layer in this order from the semiconductor light emitting element 14 side, it is possible to obtain a white light emitting device with extremely excellent luminous efficiency.

Next, the phosphor contained in the light emitting layer will be described.
(Green phosphor)
Any green phosphor can be used as long as the effects of the present invention are not significantly impaired.
The emission peak wavelength of the green phosphor is preferably 510 nm or more, preferably 520 nm or more, and usually 540 nm or less, preferably 530 nm or less.

As such a green phosphor, for example,
(Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu-activated alkaline earth silicon oxynitride phosphor represented by Eu,
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, Sr, Ca, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Euopium activated silicate phosphors such as Eu Can be mentioned.

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 boric acid phosphor such as Eu,
Eu-activated halosilicate phosphors such as Sr ₂ Si ₃ O ₈ -2SrCl ₂ : Eu,
Zn ₂ SiO ₄ : Mn-activated silicate phosphor such as Mn,
Tb-activated aluminate phosphors such as CeMgAl ₁₁ O ₁₉ : Tb, Y ₃ Al ₅ O ₁₂ : Tb,
Tb activated silicate phosphors such as Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Tb, La ₃ Ga ₅ SiO ₁₄ : Tb, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm, etc. Eu, Tb, Sm activated thiogallate phosphor,
Ce activated aluminate phosphors such as Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Gd, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce Can be mentioned.

Ce activated silicate phosphors such as Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce,
CaSc ₂ O ₄ : Ce-activated oxide phosphor such as Ce,
Eu-activated oxynitride phosphors such as Eu-activated β sialon,
BaMgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphor such as Eu, Mn,
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,
Examples include LaPO ₄ : Ce, Tb-loaded intelligent phosphate phosphors such as Ce and Tb.

Sulfide phosphors such as ZnS: Cu, Al, ZnS: Cu, Au, Al,
_{(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: K Ce, Tb activated borate phosphors such as
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,
Examples include Eu activated nitride phosphors such as M ₃ Si ₆ O ₉ N ₄ : Eu, M ₃ Si ₆ O ₁₂ N ₂ : Eu (where M is an alkaline earth metal element).

Furthermore, as other green phosphors, for example, pyridine-phthalimide condensed derivatives, benzoxazinone-based, quinazolinone-based, coumarin-based, quinophthalone-based, naltalimide-based fluorescent pigments, and organic phosphors such as terbium complexes are used. It is also possible.
Any one of these green phosphors may be used, or two or more thereof may be used in combination.

(Red phosphor)
Any red phosphor can be used as long as the effects of the present invention are not significantly impaired.
The emission peak wavelength of this red phosphor is usually in the wavelength range of usually 580 nm or more, preferably 585 nm or more, and usually 780 nm or less, preferably 700 nm or less.
As such a red phosphor, for example,
(Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Europium-activated alkaline earth silicon nitride-based phosphor represented by Eu,
Examples include (Y, La, Gd, Lu) ₂ O ₂ S: Euopium-activated rare earth oxychalcogenide phosphors represented by Eu.

Other red phosphors include
(La, Y) ₂ O ₂ S: Eu-activated sulfide phosphors such as Eu,
Eu-activated oxide phosphors such as Y (V, P) O ₄ : Eu, Y ₂ O ₃ : Eu,
(Ba, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn activated silicate phosphor such as Eu, Mn,
Eu-activated tungstate phosphors such as 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,
Eu-activated sulfide phosphors such as (Ca, Sr) S: Eu are listed.

YAlO ₃ : Eu-activated aluminate phosphor such as Eu,
Eu-activated silicic acid such as Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Eu, LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu, (Sr, Ba, Ca) ₃ SiO ₅ : Eu, Sr ₂ BaSiO ₅ : Eu Salt phosphor,
_{(Y, Gd) 3 Al 5} O 12: Ce, (Tb, Gd) 3 Al 5 O 12: Ce, (Y, Mn) 3 (Al, Si) 5 O 12: Ce -activated aluminate phosphor such as Ce body,
(Mg, Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Mg, Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Eu-activated oxide such as Eu, nitride, or oxynitride phosphor,
Examples thereof include Ce-activated oxides such as (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, nitrides, or oxynitride phosphors.

  (Sr, Ca, Ba, Mg) 10 (PO4) 6Cl2: Eu, Mn, etc. Eu, Mn activated halophosphate phosphor, Ba3MgSi2O8: Eu, Mn, (Ba, Sr, Ca, Mg) 3 (Zn, Mg) Eu 2 O 8: Eu, Mn activated silicate phosphor such as Eu, Mn, 3.5 MgO · 0.5 MgF 2 · GeO 2: Mn activated germanate phosphor such as Mn, Eu activated oxynitride phosphor such as Eu activated α sialon (Gd, Y, Lu, La) 2O3: Eu, Bi-activated oxide phosphors such as Eu and Bi, (Gd, Y, Lu, La) 2O2S: Eu, Bi-activated oxysulfide fluorescent materials such as Eu and Bi And (Gd, Y, Lu, La) VO4: Eu, Bi activated vanadate phosphors such as Eu and Bi, and the like.

SrY ₂ S ₄ : Eu, Ce-activated sulfide phosphors such as Eu and Ce,
CaLa ₂ S ₄ : Ce-activated sulfide phosphor such as Ce,
(Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba, Mg, Zn) ₂ P ₂ O ₇ : Eu, Mn activated phosphate phosphors such as Eu, Mn,
(Y, Lu) ₂ WO ₆ : Eu, Mo-activated tungstate phosphor such as Eu, Mo, etc.
(Ba, Sr, Ca) _x Si _y Nz: Eu, Ce activated nitride phosphor such as Eu, Ce (where x, y, z are integers of 1 or more),
(Ca, Sr, Ba, Mg) ₁₀ (PO ₄ ) ₆ (F, Cl, Br, OH): Eu, Mn-activated halophosphate phosphor such as Eu, Mn,
((Y, Lu, Gd, Tb) _1-xy Sc _x Ce _y ) ₂ (Ca, Mg) _1-r (Mg, Zn) _{2 + r} Si _{2 -q} Ge _q O _{12 + δ} etc. Ce-activated silicate fluorescence Examples include the body.

Furthermore, as other red phosphors, for example, β-diketonate, β-diketone, aromatic carboxylic acid, or a red organic phosphor comprising a rare earth element ion complex having an anion such as Bronsted acid as a ligand, Penylene pigments such as dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene, Anthraquinone pigments, lake pigments, azo pigments, quinacridone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments, India Phenol pigments, cyanine pigments, and dioxazine pigments can also be used.
Any one of these red phosphors may be used, or two or more thereof may be used in combination.

(Blue phosphor)
Any blue phosphor can be used as long as the effects of the present invention are not significantly impaired.
The emission peak wavelength of this blue phosphor is usually in the wavelength range of usually 420 nm or more, preferably 430 nm or more, and usually 490 nm or less, preferably 470 nm or less.

As such a blue phosphor, for example,
(Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Europium-activated barium magnesium aluminate-based phosphor represented by Eu,
(Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ (Cl, F): Europium-activated calcium halophosphate phosphor represented by Eu,
(Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: Europium-activated alkaline earth chloroborate phosphor represented by Eu,
Examples thereof include a europium activated alkaline earth aluminate phosphor represented by (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba) ₄ Al ₁₄ O ₂₅ : Eu.

Other blue phosphors include Sn-activated phosphate phosphors such as Sr ₂ P ₂ O ₇ : Sn,
Ce-activated thiogallate phosphors such as SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce,
(Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphor such as Eu, Mn,
Sulfide phosphors such as ZnS: Ag, ZnS: Ag, Al,
Y ₂ SiO ₅ : Ce-activated silicate phosphor such as Ce,
CaWO ₄ tungstate phosphor,
Eu-activated oxynitride phosphors such as SrSi ₉ Al ₁₉ ON ₃₁ : Eu and EuSi ₉ Al ₁₉ ON ₃₁ can also be used.

Further, as other blue phosphors, for example, naphthalic acid imide-based, benzoxazole-based, styryl-based, coumarin-based, pyralizone-based, triazole-based fluorescent dyes, organic phosphors such as thulium complexes, etc. can be used. It is.
Any one of these blue phosphors may be used, or two or more thereof may be used in combination.

(Yellow phosphor)
Any yellow phosphor can be used as long as the effects of the present invention are not significantly impaired.
The emission peak wavelength of this yellow phosphor is usually in the wavelength range of usually 550 nm or more, preferably 560 nm or more, and usually 620 nm or less, preferably 600 nm or less.
Examples of such yellow phosphors 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 is one or more selected from the group of Y, Tb, Gd, Lu and Sm, and M is selected from the group of Al, Ga and Sc) 1 type or 2 types or more), Ma ₃ Mb ₂ Mc ₃ O ₁₂ : Ce (where Ma is a divalent metal element, Mb is a trivalent metal element, Mc is a tetravalent metal element), etc. A garnet phosphor having a garnet structure,
AE ₂ MdO ₄ : Eu (where AE is one or more selected from the group of Ba, Sr, Ca, Mg and Zn, and Md is any one of Si, Ge, Si and Ge), etc. Orthosilicate phosphors represented,
Oxynitride phosphors in which part of the constituent element oxygen of these phosphors is replaced by nitrogen,
Phosphors activated with Ce such as nitride phosphors having a CaAlSiN ₃ structure such as AEAlSiN ₃ : Ce (where AE is one or more selected from the group of Ba, Sr, Ca, Mg and Zn) Is mentioned.

Furthermore, as other yellow phosphors, for example, sulfides such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu, etc. Phosphor,
It is also possible to use a phosphor activated with Eu such as an oxynitride-based phosphor having a SiAlON structure such as Ca _x (Si, Al) ₁₂ (O, N) ₁₆ : Eu.
Examples of the yellow phosphor include fluorescent dyes such as brilliant sulfoflavine (Colour Index Number 56205), basic yellow HG (Colour Index Number 46040), eosine (Colour Index Number 45380), and rhodamine 6G (Colour Index Number 45160). It is also possible to use it.

(Phosphor combination)
The green phosphor, red phosphor, blue phosphor, and yellow phosphor (except for the composite wavelength conversion particle of the present embodiment) may use one kind of phosphor alone, or two or more kinds of fluorescence. The body may be used in any combination and ratio.
Further, the ratio of the composite wavelength conversion particles of the present embodiment to the above various phosphors is also arbitrary as long as the effects of the present invention are not significantly impaired. Therefore, the usage amount of the various phosphors and the combination and ratio of the phosphors used as the various phosphors may be arbitrarily set according to the use of the light emitting device.

  In the light emitting device of the present embodiment, the presence or absence of the specifications of the green phosphor, the red phosphor, the blue phosphor, and the yellow phosphor (excluding the composite wavelength conversion particle of the present embodiment) and the type thereof are the same as those of the light emitting device. What is necessary is just to select suitably according to a use. For example, when the light-emitting device of this embodiment is configured as a light-emitting device that emits yellow light, only the composite wavelength conversion particles of this embodiment may be used, and the various phosphors described above are usually unnecessary.

On the other hand, when the light emitting device of the present embodiment is configured as a light emitting device that emits white light, the semiconductor light emitting element 14, the composite wavelength conversion particle of the present embodiment, What is necessary is just to combine various fluorescent substance appropriately.
Specifically, when the light-emitting device of this embodiment is configured as a light-emitting device that emits white light, a preferable combination of the composite wavelength conversion particle of this embodiment and the various phosphors described above is as follows (i ) To (ii).

(I) A blue light emitting element (blue LED or the like) is used as the semiconductor light emitting element, a yellow phosphor containing the composite wavelength conversion particles of the present embodiment is used as the yellow phosphor, and a red phosphor or green is used as the other phosphor. Any one or two of the phosphors are used.
In this case, the red phosphor is preferably at least one selected from (Sr, Ca) AlSiN ₃ : Eu and (Sr, Ba) ₃ SiO ₅ : Eu.
Further, as the green phosphor, for example, an Eu-activated alkaline earth silicon oxynitride phosphor represented by (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu, Ca ₃ (Sc, Mg) , Na, Li) ₂ Si ₃ O ₁₂ : One or more selected from Ce-activated silicate phosphors such as Ce are preferable.

(Ii) A near-ultraviolet light-emitting element (near-ultraviolet LED or the like) is used as a semiconductor light-emitting element, a yellow phosphor containing the composite wavelength conversion particles of the present embodiment is used as a yellow phosphor, and a blue phosphor as another phosphor A red phosphor and a green phosphor are used.
In this case, the blue phosphor is at least selected from (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu and (Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ (Cl, F): Eu. One is preferred.
The red phosphor is preferably at least one selected from (Sr, Ca) AlSiN ₃ : Eu and La ₂ O ₂ S: Eu.
Examples of green phosphors include (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphors such as Eu, Tb, and Sm, Eu activated oxynitride phosphors such as Eu activated β sialon, SrAl Eu-activated aluminate phosphors such as ₂ O ₄ : Eu, Eu, Mn-activated aluminate phosphors such as BaMgAl ₁₀ O ₁₇ : Eu, Mn, and the like are preferable.

(resin)
As the resin for dispersing the composite wavelength conversion particles of the present embodiment and the various phosphors described above, the resin used in the above-described composite wavelength conversion particle-containing resin composition is preferably used.

In the light emitting device, instead of each light emitting layer, the composite wavelength conversion particle of the present embodiment, the green phosphor, the red phosphor, the blue phosphor, and the yellow phosphor as necessary (this embodiment) A light emitting film in which a composite wavelength converting particle) is dispersed in a plastic film, or a wavelength conversion sheet or film in which these composite wavelength converting particles and the above-mentioned various phosphors are coated on a plastic surface. It is good also as attaching to the side.
The use of the above light emitting device is not particularly limited, and can be used in various fields where a normal light emitting device is used. However, since the light emitting efficiency is high and the color rendering property is also high, the lighting device or the image is used. It is suitable as a light source for a display device.

  As described above, according to the composite wavelength conversion particle of the present embodiment, it is made of a fluoride containing one or more selected from the group of magnesium fluoride, calcium fluoride, and strontium fluoride. Since the yttrium aluminum garnet phosphor is dispersed in the matrix particles, and the maximum emission intensity is in the wavelength region of 560 nm or more and 580 nm or less, the light utilization efficiency and the particle utilization efficiency are increased. Therefore, light can be emitted with high efficiency. In addition, since this high-efficiency light emission is stable over a long period of time, the reliability can be improved.

In addition, since the yttrium aluminum garnet phosphor is dispersed in the matrix particles having a large coefficient of thermal expansion, a large compressive stress can be generated in the matrix particles to distort the crystal structure of the yttrium aluminum garnet phosphor. The emission wavelength can be increased.
As described above, both high-efficiency light emission and high reliability can be achieved.

  According to the composite wavelength conversion particle-containing resin composition of the present embodiment, since the composite wavelength conversion particles of the present embodiment are dispersed in the resin, the light utilization efficiency and the utilization efficiency of the resin composition itself can be increased. Therefore, light can be emitted with high efficiency. In addition, since this high-efficiency light emission is stable over a long period of time, the reliability can be improved.

  According to the light emitting device of this embodiment, a semiconductor light emitting element that emits light in a wavelength region of 300 nm or more and 500 nm or less, and a light emitting layer that emits visible light by receiving light emitted from the semiconductor light emitting element, The composite wavelength conversion particles of the present embodiment are contained in the light emitting layer, so that the light utilization efficiency and the utilization efficiency of the resin composition itself can be increased, and therefore light can be emitted with high efficiency. Further, the reliability can be improved over a long period of time.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited to a following example.

"Composite wavelength conversion particles"
"Example 1"
(Production of magnesium fluoride colloid)
Magnesium chloride hexahydrate (MgCl ₂ · 6H ₂ O) 406.6 g was dissolved in 2000 g of pure water (room temperature: 25 ° C.) to prepare an aqueous magnesium chloride solution. Next, an ammonium fluoride aqueous solution in which 148.2 g of ammonium fluoride (NH ₄ F) was dissolved in 2000 g of pure water (room temperature: 25 ° C.) was added to this solution while stirring to produce magnesium fluoride particles.
Next, the solution containing the magnesium fluoride particles is subjected to ultrafiltration washing to remove impurity ions in the solution and then concentrated to a magnesium fluoride colloid containing 2% by mass of magnesium fluoride (MgF ₂ ) particles. Was made.

The dispersed particle size of the magnesium fluoride colloid was measured using a light transmission type particle size distribution measuring device, and found to be 30 nm.
Magnesium fluoride was separated from this magnesium fluoride colloid, dried, and the crystallite diameter of the obtained magnesium fluoride (MgF ₂ ) particles was measured by a powder method using an X-ray diffractometer, and found to be 8 nm. .

(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions as luminescent ions was set to x = 0.54, y = 0, and w = 0 in the above equation (1).

Moreover, 380 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an aqueous ammonium hydrogen carbonate solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 301.90g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 151.66g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 37.74 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of the above magnesium fluoride colloid and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloid solution, and then dried with a two-fluid nozzle spray dryer. Next, the obtained dried product was heat-treated at 550 ° C. for 2 hours in the air atmosphere to thermally decompose the precursor of the YAG: Ce phosphor to obtain calcined particles.
Next, the fired particles were subjected to heat treatment at 1050 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen to produce composite wavelength conversion particles of Example 1.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm. Scanning electron microscope (SEM) images of the composite wavelength conversion particles are shown in FIGS.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of MgF ₂ was 25 nm and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
The mass ratio (Mp: Ms) of the above composite wavelength conversion particles (Mp) and the two-pack type silicone resin OE6630 (refractive index: 1.53, manufactured by Toray Dow Co., Ltd.) (Ms) is 25:75. Then, the above composite wavelength conversion particles and the silicone resin were weighed and kneaded in an agate mortar. The silicone resin was 42.8 parts by mass of the main agent and 32.2 parts by mass of the curing agent.

Next, this kneaded product was applied on a transparent glass substrate with a bar coater, then heated and cured at 150 ° C. for 60 minutes, and the wavelength of Example 1 for measuring the emission intensity of 30 μm in thickness on this transparent glass substrate. A conversion film was formed.
On the other hand, a commercially available YAG: Ce phosphor P46-Y3 (YAG particle size: 6 μm to 8 μm, manufactured by Kasei Opto Co., Ltd.) was used as a wavelength conversion film for measuring the emission characteristics for comparison. In the same manner as the wavelength conversion film of Example 1, a comparative wavelength conversion film for measuring the emission intensity having a thickness of 30 μm was formed on a transparent glass substrate.

Next, the quantum efficiencies of the emission spectra of the wavelength conversion film of Example 1 and the comparative wavelength conversion film were measured by the transmission method using an integrated hemispherical quantum efficiency measurement system QE2000 (manufactured by Otsuka Electronics Co., Ltd.). It was measured.
Here, the sample area of the transmitted light is a rectangular shape of 5 mm × 6 mm, the excitation light is incident from behind the wavelength conversion film (glass substrate side), and the emission spectrum in front of the wavelength conversion film is collected by the integrating hemisphere. 560 nm emission photon amount (equivalent to external quantum efficiency) emitted forward with respect to the incident 460 nm excitation light photon amount was measured, and the wavelength conversion film of Example 1 per 1 g of the composite wavelength conversion particle, on the other hand, the comparative wavelength conversion film Were converted per YAG per gram, and the emission characteristics in the forward direction of the composite wavelength conversion particles of Example 1 and the phosphor for comparison were compared (front emission characteristics ratio).

Here, with respect to the wavelength conversion films of Example 1 and each of the comparative examples, the forward emission characteristics (forward emission 560 nm photon amount / incident 460 nm excitation light) per 1 g of the light emitter are determined by the forward emission 560 nm photon amount and the incident 460 nm excitation light photon amount. The amount of photons) was calculated, and then the ratio of the front emission characteristics per 1 g of the composite wavelength conversion particle of Example 1 to the front emission characteristics per 1 g of the comparative phosphor was calculated and used as the front emission characteristics ratio.
At the same time, the emission peak wavelength and the half width of the emission spectrum were also measured.

Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 2]
(Preparation of calcium fluoride colloid)
376.6 g of calcium chloride dihydrate (CaCl ₂ .2H ₂ O) was dissolved in 9624 g of pure water (room temperature: 25 ° C.) to prepare an aqueous calcium chloride solution. Next, an ammonium fluoride aqueous solution in which 190 g of ammonium fluoride (NH ₄ F) was dissolved in 9810 g of pure water (room temperature: 25 ° C.) was added to this solution while stirring to generate calcium fluoride particles.
Next, the solution containing calcium fluoride particles is subjected to ultrafiltration washing to remove impurity ions in the solution, and then concentrated to obtain a calcium fluoride colloid containing 2% by mass of calcium fluoride (CaF ₂ ) particles. Was made.
The dispersed particle diameter of the calcium fluoride colloid was 80 nm, and the crystallite diameter of the calcium fluoride (CaF ₂ ) particles was 20 nm.

(Preparation of phosphor precursor solution with garnet structure)
In accordance with Example 1, an aqueous solution of glyoxylic acid of Al, Y, and Ce was prepared as a phosphor precursor.

(Production of composite wavelength conversion particles)
200 g of the above calcium fluoride colloid and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to form a uniform colloid solution, and then dried with a two-fluid nozzle spray dryer. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, to produce composite wavelength conversion particles of Example 2.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 2, a wavelength conversion film for measuring light emission characteristics of Example 2 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 3]
(Preparation of phosphor precursor solution with garnet structure)
In accordance with Example 1, an aqueous solution of glyoxylic acid of Al, Y, and Ce was prepared as a phosphor precursor.

(Production of composite wavelength conversion particles)
A two-fluid nozzle type spray dryer is prepared by mixing and stirring 200 g of calcium fluoride colloid prepared according to Example 2 and 42.9 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce to obtain a uniform colloidal solution. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen to produce composite wavelength conversion particles of Example 3.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm and the crystallite diameter of YAG was 50 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 3, a wavelength conversion film for measuring light emission characteristics of Example 3 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 4]
(Preparation of phosphor precursor solution with garnet structure)
In accordance with Example 1, an aqueous solution of glyoxylic acid of Al, Y, and Ce was prepared as a phosphor precursor.

(Production of composite wavelength conversion particles)
A two-fluid nozzle type spray dryer is prepared by mixing and stirring 200 g of calcium fluoride colloid prepared according to Example 2 and 66.7 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce to obtain a uniform colloidal solution. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 4 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 4, a wavelength conversion film for measuring light emission characteristics of Example 4 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 5]
(Preparation of phosphor precursor solution with garnet structure)
In accordance with Example 1, an aqueous solution of glyoxylic acid of Al, Y, and Ce was prepared as a phosphor precursor.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 150 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 5 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 75 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 5, a wavelength conversion film for measuring light emission characteristics of Example 5 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 6]
(Preparation of phosphor precursor solution with garnet structure)
In accordance with Example 1, an aqueous solution of glyoxylic acid of Al, Y, and Ce was prepared as a phosphor precursor.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 233 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, to produce composite wavelength conversion particles of Example 6.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 80 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 6, a wavelength conversion film for measuring light emission characteristics of Example 6 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 7]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions, which are luminescent ions, was x = 0.39, y = 0, and w = 0 in the above equation (1).

Moreover, 382 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 305.68g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 162.92g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 27.60 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Further, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 7 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm and the crystallite diameter of YAG was 110 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 7, a wavelength conversion film for measuring light emission characteristics of Example 7 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 8]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions, which are luminescent ions, was x = 0.39, y = 0, and w = 0 in the above equation (1).

Moreover, 374 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10000 g of pure water to prepare an aqueous ammonium hydrogen carbonate solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 310.38g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 176.81g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 15.09 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Further, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 8 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm and the crystallite diameter of YAG was 110 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 8, a wavelength conversion film for measuring light emission characteristics of Example 8 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 9]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions as luminescent ions was set to x = 0.6, y = 0, and w = 0 in the above equation (1).

Moreover, 380 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an aqueous ammonium hydrogen carbonate solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 300.42g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 147.23g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 41.73g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Further, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 9 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite size of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite size of CaF ₂ was 40 nm and the crystallite size of YAG was 95 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 9, a wavelength conversion film for measuring light emission characteristics of Example 9 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 10]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions as luminescent ions was set to x = 0.75, y = 0, and w = 0 in the above equation (1).

Further, 379 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 296.77g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 136.35g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 51.53g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Further, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 10 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 10, a wavelength conversion film for measuring light emission characteristics of Example 10 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 11]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions as luminescent ions was set to x = 0.9, y = 0, and w = 0 in the above equation (1).

Further, 378 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 293.21g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 125.73g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 61.09g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, to produce composite wavelength conversion particles of Example 11.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 11, a wavelength conversion film for measuring light emission characteristics of Example 11 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Example 12]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as a phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, Ce, and Gd was prepared as a precursor of the YAG: Ce phosphor. In the precursor of this YAG: Ce phosphor, the concentrations of Ce ions and Gd ions, which are luminescent ions, are x = 0.3, z = 0.75, w = 0.

Further, 313 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate (Al (NO ₃ ) ₃ · 9H ₂ O: molecular weight 375.13) 284.07 g, yttrium nitrate hexahydrate (Y (NO ₃ ) ₃ · 6H ₂ O: molecular weight 383. 01) 113.11g, cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 19.73 g, and gadolinium nitrate _{(Gd (NO 3) 3 ·} 6H 2 O: molecular weight 451 .36) 51.27 g was dissolved in 5000 g of pure water (room temperature: 25 ° C.) to prepare a nitrate aqueous solution.

  Next, the nitrate aqueous solution is added to the ammonium hydrogen carbonate aqueous solution to produce a precipitate of Al, Y, Ce, and Gd hydroxy carbonate, and this precipitate is washed with an ultrafiltration device to remove impurity ions. Then, solid-liquid separation was performed with a vacuum filtration device, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce, Gd hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce, and Gd was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, Ce, and Gd are mixed and stirred to form a uniform colloid solution, and then a two-fluid nozzle type spray dryer Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Example 12 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm and the crystallite diameter of YAG was 50 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Example 12, a wavelength conversion film for measuring light emission characteristics of Example 12 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Comparative Example 1]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions, which are luminescent ions, was x = 0.39, y = 0, and w = 0 in the above equation (1).

Moreover, 382 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 305.68g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 162.92g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 27.60 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
After mixing 400 g of calcium fluoride colloid prepared according to Example 2 and 35.28 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce to obtain a uniform colloidal solution, a two-fluid nozzle type spray dryer Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Comparative Example 1 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 30 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Comparative Example 1, a wavelength conversion film for measuring light emission characteristics of Comparative Example 1 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, no change was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Comparative Example 2]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions, which are luminescent ions, was x = 0.39, y = 0, and w = 0 in the above equation (1).

Moreover, 382 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 305.68g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 162.92g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 27.60 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 300 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to form a uniform colloid solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Further, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Comparative Example 2 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 120 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Comparative Example 2, a wavelength conversion film for measuring light emission characteristics of Comparative Example 2 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, a slight decrease was observed in the forward light emission characteristics.
These results are shown in Table 2.

[Comparative Example 3]
(Preparation of phosphor precursor solution with garnet structure)
A rare earth aluminate-based phosphor precursor solution was prepared as a phosphor precursor.
Here, a YAG: Ce phosphor was selected as the phosphor having a garnet structure, and an aqueous solution of glyoxylic acid (glyoxylic acid complex aqueous solution) of Al, Y, and Ce was prepared as a precursor of the YAG: Ce phosphor. In this YAG: Ce phosphor precursor, the concentration of Ce ions, which are luminescent ions, was x = 0.39, y = 0, and w = 0 in the above equation (1).

Further, 378 g of ammonium hydrogen carbonate (NH ₄ HCO ₃ ) was dissolved in 10,000 g of pure water to prepare an ammonium hydrogen carbonate aqueous solution.
Furthermore, aluminum nitrate nonahydrate _{(Al (NO 3) 3 ·} 9H 2 O: molecular weight 375.13) 311.13g, yttrium nitrate hexahydrate _{(Y (NO 3) 3 ·} 6H 2 O: molecular weight 383. 01) 179.17g, and cerium nitrate hexahydrate _{(Ce (NO 3) 3 ·} 6H 2 O: molecular weight 434.23) 12.97 g of pure water 5000 g (RT: dissolved in 25 ° C.), the aqueous nitrate solution Produced.

  Next, the aqueous nitrate solution is added to the aqueous ammonium bicarbonate solution to produce a precipitate of Al, Y, Ce hydroxy carbonate, and the precipitate is washed using an ultrafiltration device to remove impurity ions. Next, solid-liquid separation was performed with a vacuum filtration apparatus, and the obtained cake was dried at 120 ° C. for 24 hours to obtain dry particles of Al, Y, Ce hydroxycarbonate. Next, 33.9 g (20 g in terms of YAG: Ce) of the dried particles was added to 466.1 g of an aqueous glyoxylic acid solution containing 58.6 g of glyoxylic acid, and then stirred at room temperature (25 ° C.) for 24 hours. A glyoxylic acid aqueous solution of Al, Y, Ce was prepared.

(Production of composite wavelength conversion particles)
200 g of calcium fluoride colloid prepared according to Example 2 and 100 g of an aqueous solution of glyoxylic acid of Al, Y, and Ce were mixed and stirred to obtain a uniform colloidal solution, and then a two-fluid nozzle type spray dryer. Dried. Next, the obtained dried product was heat-treated at 600 ° C. for 2 hours in an air atmosphere.
Furthermore, heat treatment was performed at 1150 ° C. for 5 hours in a reducing atmosphere containing a mixed gas of 3% hydrogen and 97% nitrogen, and composite wavelength conversion particles of Comparative Example 3 were produced.

When the particle diameter of this composite wavelength conversion particle was measured using a scanning electron microscope (SEM), it was distributed in the range of 1 μm to 8 μm.
Further, when the crystallite diameter of the composite wavelength conversion particles was measured by a powder method using an X-ray diffractometer, the crystallite diameter of CaF ₂ was 40 nm, and the crystallite diameter of YAG was 60 nm.

(Production and evaluation of composite wavelength conversion particle-containing resin composition)
Using the composite wavelength conversion particles of Comparative Example 3, a wavelength conversion film for measuring light emission characteristics of Comparative Example 3 was produced according to Example 1.
Next, the light emission characteristics of the wavelength conversion film were measured according to Example 1.
Next, the wavelength conversion film was stored in a high-temperature and high-humidity tester having a temperature of 85 ° C. and a humidity of 85% for 500 hours, and the wavelength conversion film after storage was evaluated for the forward emission characteristic ratio by the same method as described above. However, forward light emission characteristics were not recognized.
These results are shown in Table 2.

[Evaluation by XAFS]
For the composite wavelength conversion particle of Example 7, the X-ray absorption near-edge fine structure (XANES) spectrum of the Ce-L3 absorption edge of Ce ions was installed in the High Energy Accelerator Research Organization. XAFS (X-ray Absorption Fine Structure) measuring apparatus. Here, cerium acetate was used as a trivalent cerium standard sample, and cerium oxide was used as a tetravalent cerium standard sample. As a result, it was confirmed that all of Ce ions (100%) were trivalent.
FIG. 7 shows an X-ray absorption near-edge fine structure (XANES) spectrum of the Ce-L3 absorption edge in the composite wavelength conversion particle of Example 7.

Further, for each of the composite wavelength conversion particles of Examples 7, 8, and 10, Ce-Al (Y) in the structure around Ce atoms (Ce-K absorption edge radial structure function) using the above-described XAFS measurement apparatus. The distance between ions and the distance between Ce-O ions were measured. In FIG. 8, the measurement result of the distance between ions in each of the composite wavelength conversion particles of Examples 7, 8, and 10 is shown.
As a result, it was confirmed that the peak position at an interatomic distance of about 3 mm was shortened with an increase in Ce concentration. Therefore, as the distance between Ce and Al ions is shortened, the crystal field splitting of Ce ions, which are luminescent ions, is further increased. Therefore, in the composite wavelength conversion particle of the present embodiment, even if the Ce concentration is increased more than ever before. It was found that light can be emitted with high efficiency without quenching.
Therefore, it has been found that the composite wavelength conversion particles of the present embodiment are extremely superior in light emission characteristics and reliability in the forward direction.

"Light Emitting Device"
[Example 13]
Using the composite wavelength conversion particles of Example 2, the surface-mounted light-emitting device shown in FIG.
The light emitting device was manufactured by the following procedure.

  As the semiconductor light emitting element 14, a blue light emitting diode (blue LED) ES-CEBL 912 (manufactured by EPISTAR) that emits light with a wavelength of 450 nm to 470 nm is used. Bonding was performed, and the silver paste was heated at 150 ° C. for 2 hours to harden the silver paste to obtain an electrode 16. Next, a gold wire with a diameter of 25 μm was used as the bonding wire 18, and the blue LED and the electrode 17 were wire bonded using this gold wire.

As the light-emitting substance contained in the light-emitting layer 15, Sr _0.8 Ca, which is a red phosphor that emits light having a wavelength of 520 nm to 760 nm as the red phosphor 24, using the composite wavelength conversion particle of Example 2 as a yellow phosphor. Eu activated β sialon, which is a green phosphor that emits light having a wavelength of 500 nm to 560 nm, was used as the green phosphor 23 using _0.192 Eu _0.008 AlSiN ₃ .
Here, the mass ratio of the yellow phosphor, the red phosphor, and the green phosphor was set to 50:25:25. The main component of silicone resin OE6630 (manufactured by Toray Dow Co., Ltd.) is added to the total mass of these yellow phosphor, red phosphor and green phosphor to a mass ratio of 8: 107, and further mixed. A curing agent was added at a ratio of 100: 70 with respect to the total mass of the resin mixture containing the various phosphors and the silicone resin, and mixed with a kneader to prepare a phosphor slurry (phosphor-containing resin composition).

Next, this phosphor slurry was poured into the concave portion 13 of the frame 12 and cured by heating at 150 ° C. for 2 hours to obtain a light emitting layer 15.
As described above, a surface-mounted light-emitting device of Example 13 was produced.

Next, this surface mount type light emitting device is driven by applying a current of 20 mA to a blue LED to emit light, and using a spectroscope USB2000 (integral sphere specification) and color / illuminance measurement software (manufactured by Ocean Optics). The white chromaticity coordinates of this surface-mounted light emitting device were measured.
The measurement of the white chromaticity coordinates is performed by using chromaticity values (x, x, This was done by calculating y).
The white chromaticity coordinates of this surface-mounted light-emitting device were (x, y) = (0.31, 0.33), which was almost achromatic white light emission.

  The composite wavelength conversion particle of the present invention is a yttrium aluminum garnet-based matrix particle made of a fluoride containing one or more selected from the group consisting of magnesium fluoride, calcium fluoride and strontium fluoride. By dispersing the phosphor and further setting the maximum value of the emission intensity to a wavelength region of 560 nm or more and 580 nm or less, the light use efficiency and the particle use efficiency can be increased, and therefore light is emitted with high efficiency. In addition, since this high-efficiency light emission is stable over a long period of time, the reliability can be improved, so various display devices, lighting devices, solar power generation devices, photonic devices, It is useful as a light emitting material for various optical devices such as optical amplifiers, and its industrial value is great.

DESCRIPTION OF SYMBOLS 1 Composite wavelength conversion particle | grains 2 Matrix particle | grain 3 Yttrium aluminum garnet-type fluorescent substance 11 Surface mount type light-emitting device 14 Semiconductor light emitting element 15 Light emitting layer 21 Resin having transparency 22 Compound wavelength conversion particle 23 Green fluorescent substance 24 Red fluorescent substance 31 Surface mount Type light emitting device 32 composite wavelength conversion particle-containing resin layer 33 phosphor-containing resin layer 34 light emitting layer 41 surface mount type light emitting device 42 resin 43 light emitting layer

Claims (6)

Yttrium aluminum garnet phosphor is dispersed in matrix particles made of fluoride containing one or more selected from the group of magnesium fluoride, calcium fluoride and strontium fluoride,
A composite wavelength conversion particle having a maximum value of emission intensity in a wavelength region of 560 nm or more and 580 nm or less. The yttrium aluminum garnet phosphor is
_{(Y 3-x-z Ce} x M z) (Al 5-y-w R w Si y) O 12 ...... (1)
(However, M is at least one of lanthanoid and Bi excluding Ce, R is at least one of In and Ga, and 0.21 ≦ x ≦ 0.9, 0 ≦ y ≦ 1.5, 0 ≦ z ≦ 1.5, 0 ≦ w ≦ 1.0)
The composite wavelength conversion particle according to claim 1, comprising:   3. The composite wavelength conversion particle according to claim 1, wherein a mass percentage of the yttrium aluminum garnet-based phosphor with respect to the fluoride is 20% by mass or more and 70% by mass or less.   A composite wavelength conversion particle-containing resin composition, wherein the composite wavelength conversion particle according to any one of claims 1 to 3 is dispersed in a resin. A semiconductor light emitting element that emits light in a wavelength region of 300 nm or more and 500 nm or less, and a light emitting layer that emits visible light by receiving light emitted from the semiconductor light emitting element,
The light emitting device is characterized in that the light emitting layer contains the composite wavelength conversion particles according to any one of claims 1 to 3.   The light emitting device according to claim 5, wherein the light emitting layer contains one or more of a yellow phosphor, a blue phosphor, a green phosphor, and a red phosphor.