JP2015130459A - Phosphor-containing multilayer film sheet and light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor-containing multilayer film sheet that can achieve both of high luminance and high color rendering property of a light-emitting device using a light source of blue or ultraviolet light, such as a white LED, can simplify chromaticity adjustment of a light source in manufacturing processes, and suppress color irregularity.SOLUTION: The phosphor-containing multilayer film sheet is composed of two or more layers of a resin composition essentially comprising a resin (A), each layer having a thickness of 0.2 to 0.5 mm, and contains two or more kinds of phosphors including at least a red phosphor and a green phosphor. Each of at least two layers in the sheet contains one of the above phosphors; and a phosphor emitting light at a longer wavelength is disposed closer to a light-emitting element. A fine rugged structure smaller than a wavelength of visible light (400 to 800 nm) is formed on at least a surface where light enters and a surface where the received light exits to the outside.

Description

  The present invention includes a phosphor-containing multilayer film sheet that can be used in various light emitting devices such as a white light emitting diode (white LED) using a blue light emitting diode (blue LED) or an ultraviolet light emitting diode (ultraviolet LED), and the like, The present invention relates to a light emitting device using the same.

  A light-emitting device that uses an LED as a light source has a longer life than a light bulb, is easy to miniaturize, and can be driven at a constant voltage. It has attracted attention as a next-generation light source such as a lighting fixture and a backlight of a liquid crystal display element, and has been actively researched and developed in recent years.

  Conventional LED light sources use LED chips that emit blue or ultraviolet light as excitation light sources, and excite multiple phosphors to obtain red, green, and blue light, which are the three primary colors of light. The method of obtaining white light is widely used. FIG. 1 shows an enlarged view of a portion where the phosphor of the LED light source is dispersed.

However, as shown in FIG. 1, when a plurality of phosphors are contained in the same phosphor layer, there is a problem of causing “color unevenness” of light emission depending on the dispersion state of the phosphors.
In addition, when a plurality of phosphors are used, when the excitation spectrum of one phosphor overlaps with the emission spectrum of the other phosphor, a phenomenon occurs in which light emitted from the latter phosphor is absorbed by the former phosphor. . In general, since the excitation spectrum of a phosphor is located on the shorter wavelength side than the emission spectrum, this phenomenon is caused by the fact that light emitted from a phosphor having a shorter wavelength emission spectrum has an excitation spectrum in the same wavelength range as the emission spectrum. It happens when absorbed by the body. As a result, there is a problem that the luminous efficiency is lowered and high luminance cannot be obtained.

  In order to solve such problems, it has been proposed to stack a plurality of phosphor layers in the traveling direction of light from the light emitting element (for example, Patent Document 1, Patent Document 2, and Non-Patent Document). 1). As a method of creating a laminated state, the mounting position of the chip is recessed so that the top surface of the LED chip and the bottom of the package are in the same plane, and phosphors are applied to the substantially flat surface obtained thereby one by one. There is a way. In this way, it has been proposed to eliminate color unevenness due to the phosphor (Patent Document 3).

However, in the method described in the above-mentioned patent document, there is a problem in that the number of manufacturing steps is long and time is required because the layer once applied is cured after the phosphor is applied one layer, and then the next layer is applied. Further, although the color rendering properties and the light emission efficiency are compared with respect to the order in which the phosphors are stacked, the examples in which the light emission color of the light emitting device has the same chromaticity are not shown.

JP 2011-228344 A JP 2005-31136 A Patent 04653662

T. T. et al. Kitatake, “Emission color tuning of laminated and mixed SiAlON phosphor films by electrophoretic deposition”, Journal of the Ceramic Society 10, 118-

  The present invention provides a phosphor-containing multilayer sheet capable of simplifying the chromaticity adjustment of a light source and increasing the total luminous flux of the light emitting device in the manufacturing process of a light emitting device such as a white LED using blue to ultraviolet light as a light source. It is a thing.

  That is, the present invention is composed of two or more layers of a resin composition mainly composed of resin A, where epoxy resin or silicone resin is resin A, and includes a red phosphor and a green phosphor. In the phosphor-containing multilayer film sheet containing more than one kind of phosphor, the phosphor-containing multilayer film sheet is provided so as to be laminated in the traveling direction of light passing through the phosphor-containing multilayer film sheet. There are at least two phosphor layers containing phosphors, each phosphor layer contains one kind of phosphor, and other phosphors are contained in different phosphor layers, and the emission wavelength Are arranged in the traveling direction of light passing through the phosphor-containing multilayer film sheet in order from a phosphor layer containing a long phosphor to a phosphor layer containing a phosphor having a short emission wavelength, and each phosphor layer Included in The volume frequency of the phosphor is 0.4% or more and 40% or less, the thickness of each phosphor layer is 0.2 mm or more and 0.5 mm or less, and at least the light incident surface and the incident light The phosphor-containing multilayer film sheet is characterized in that a fine concavo-convex structure is provided on the surface from which light is emitted to the outside.

Moreover, it is a fluorescent substance containing multilayer film sheet whose pattern pitch distance of a fine concavo-convex structure is 0.05 micrometer-0.4 micrometer.

Moreover, it is a fluorescent substance containing multilayer film sheet whose height of the convex part of a fine concavo-convex structure is 0.05 micrometer-0.4 micrometer.

The phosphor-containing multilayer film sheet may be formed with a fine concavo-convex structure at the interface of each layer.

The phosphor-containing multilayer film sheet in which the main component of the resin A is any one selected from an epoxy resin and a silicone resin.

Furthermore, the phosphor-containing multilayer film sheet in which the main component of the resin A is a silicone resin.

The red phosphor is selected from phosphors having Eu ²⁺ as an activator and based on a crystal composed of alkaline earth silicate, alkaline earth silicate, α-SiAlON or alkaline earth silicate. It is also a phosphor-containing multilayer film sheet containing one type of phosphor.

The green phosphor has Eu ²⁺ as an activator and a green phosphor or Ce ^{3+ based} on a crystal composed of alkaline earth silicate, alkaline earth silicate nitride or β-SiAlON as an activator. It is also a phosphor-containing multilayer film sheet that is a green phosphor having a crystal composed of a garnet-type oxide or an alkaline earth metal scandate as a base material.

  The phosphor-containing multilayer sheet is characterized in that the two or more types of phosphors are formed and laminated in layers for each type.

  The fine concavo-convex structure is a phosphor-containing multilayer film sheet formed by a cutting method, a nanoimprint method, a laser fine processing, an etching method, or the like.

  Further, it is also a light emitting device comprising the above phosphor-containing multilayer sheet.

  By using the phosphor-containing multilayer film of the present invention, a sheet in which the color of the light source is adjusted to daylight and the light bulb color is adjusted, and a plurality of conventional phosphors are mixed in the same layer It is possible to obtain higher brightness than

FIG. 1 is a schematic sectional view of a conventional phosphor-containing film sheet, and is an enlarged view of a portion where phosphors are dispersed. FIG. 2 is a schematic cross-sectional view showing an embodiment of the phosphor-containing multilayer film sheet of the present invention. FIG. 3 is a schematic cross-sectional view showing another embodiment of the phosphor-containing multilayer film sheet of the present invention. FIG. 4 shows data examples of (a) CIEx and (b) CIEy of the green phosphor used for adjusting the chromaticity of the sheet. FIG. 5 shows data examples of (a) CIEx and (b) CIEy of the red phosphor used for adjusting the chromaticity of the sheet. FIG. 6 shows an emission spectrum when the periphery of the LED chip is covered with a resin having a refractive index of 1.41, and an emission spectrum when the periphery of the LED chip is covered with air having a refractive index of 1.00. FIG. 7 shows the emission spectra of Example 1, Comparative Example 1, and Comparative Example 2. FIG. 8 shows the emission spectra of Example 2, Comparative Example 3, and Comparative Example 4. FIG. 9 is an emission spectrum of the embodiment and the comparative embodiment when adjusted to daylight color. FIG. 10 is an emission spectrum of the embodiment and the comparative example when the light bulb color is adjusted. FIG. 11 is an explanatory diagram of a fine uneven structure.

  The present inventors have studied the simplification of the manufacturing process of a white LED using a known blue to ultraviolet light as an excitation light source, and studied to increase the brightness of the light source. As a result, it is composed of a resin composition mainly composed of a resin A having a refractive index of 1.3 to 1.8, and contains a phosphor containing two or more kinds of phosphors including a red phosphor and a green phosphor. In the multilayer sheet, at least two or more layers containing the phosphor are formed in the phosphor-containing multilayer film sheet, and one kind of phosphor is included in the layer containing each phosphor. Further, a phosphor having a longer emission wavelength was contained in a layer near the excitation light source, and a phosphor having a shorter emission wavelength was contained in a phosphor layer far from the excitation light source. Furthermore, by forming a fine concavo-convex structure in which the pattern pitch distance and the height of the convex portion are smaller than the wavelength of visible light on at least the light incident surface and the surface from which the incident light is emitted to the outside, It was found that light with higher luminance than that of the white LED can be obtained.

As a specific material of the resin A, a transparent resin excellent in weather resistance such as an epoxy resin and a silicone resin is preferable. In particular, it is preferable to use a silicone resin because it is excellent in reliability and can improve the dispersibility of the phosphor substance.
The refractive index of the resin A is preferably 1.3 to 1.8 in terms of light extraction efficiency. Furthermore, the thing of 1.4-1.5 is more preferable.

The phosphors are 420 nm to 500 nm (blue region), 500 nm to 555 nm (green region), 555 nm to 580 nm (yellow region), 580 nm to 600 nm (orange region), 600 nm to 630 nm (red orange region), 630 to 800 nm (red). Region) has an emission wavelength. Phosphor particles include silicon (Si), aluminum (Al), titanium (Ti), germanium (Ge), phosphorus (P), boron (B), yttrium (Y), alkaline earth elements, sulfides, rare earths At least one element or nitride is included.

A phosphor that emits light in a red-orange region or a red region becomes a red phosphor. Specifically, the following phosphors are applicable.
Y ₂ O ₂ S: Eu, Y ₂ O ₂ S: Eu + pigment, Y ₂ O ₃ : Eu, Zn ₃ (PO ₄ ) ₂ : Mn, (Zn, Cd) S: Ag + In ₂ O ₃ , (Y, Gd, Eu) BO ₃ , (Y, Gd, Eu) ₂ O ₃ , YVO ₄ : Eu, La ₂ O ₂ S: Eu, Sm, LaSi ₃ N ₅ : Eu ²⁺ , α-SiAlON: Eu ²⁺ , CaAlSiN ₃ : Eu ²⁺ , CaSiN _X : Eu ²⁺ , CaSiN _X : Ce ²⁺ , M ₂ Si ₅ N ₈ : Eu ²⁺ , CaAlSiN ₃ : Eu ²⁺ , (SrCa) AlSiN ₃ : Eu ^{X +} , Sr _x (Si _y Al ₃ ) _{z xN} ): Eu ^{X +} .

A phosphor that emits light in the green region is a green phosphor. Specifically, the following phosphors are applicable.
ZnS: Cu, Al, ZnS: Cu, Al + pigment, (Zn, Cd) S: Cu, Al, ZnS: Cu, Au, Al, + pigment, Y ₃ Al ₅ O ₁₂ : Tb, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, Y ₂ SiO ₅ : Tb, Y ₃ (Al, Ga) ₅ O ₁₂ : Tb, Y ₂ SiO ₅ : Tb, Zn ₂ SiO ₄ : Mn, (Zn, Cd) S: Cu, ZnS: Cu, Zn ₂ SiO ₄ : Mn, ZnS: Cu + Zn ₂ SiO ₄ : Mn, Gd ₂ O ₂ S: Tb, (Zn, Cd) S: Ag, ZnS: Cu, Al, Y ₂ O ₂ S: Tb, ZnS : Cu, Al + In ₂ O ₃ , (Zn, Cd) S: Ag + In ₂ O ₃ , (Zn, Mn) ₂ SiO ₄ , BaAl ₁₂ O ₁₉ : Mn, (Ba, Sr, Mg) O · aAl ₂ O ₃ : M _{, LaPO 4: Ce, Tb,} Zn 2 SiO 4: Mn, ZnS: Cu, La 2 O 3 · 0.2SiO 2 · 0.9P 2 O 5: Ce, Tb, CeMgAl 11 O 19: Tb, CaSc 2 O ₄ : Ce, (BrSr) SiO ₄ : Eu, α-SiAlON: Yb ²⁺ , β-SiAlON: Eu ²⁺ , (SrBa) YSi ₄ N ₇ : Eu ²⁺ , (CaSr) Si ₂ O ₄ N ₇ : Eu ²⁺ , Sr (SiAl) (ON): Ce.

In the phosphor-containing multilayer sheet, it is preferable to use CaAlSiN ₃ : Eu ²⁺ or (SrCa) AlSiN ₃ : Eu ^{X +} as the red phosphor. As the green phosphor, β-SiAlON: Eu ²⁺ is preferably used.

In the present invention, a phosphor that emits light in a region other than the red region and the green region may be used. Specifically, the following phosphors are applicable.
ZnS: Ag, ZnS: Ag + pigment, ZnS: Ag, Al, ZnS: Ag, Cu, Ga, Cl, ZnS: Ag + In ₂ O ₃ , ZnS: Zn + In ₂ O ₃ , (Ba, Eu) MgAl ₁₀ O ₁₇ , (Sr , Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ , 10 (Sr , Ca, Ba, Mg) · 6PO ₄ · Cl ₂ , BaMg ₂ Al ₁₆ O ₂₅ : Eu.

A method for adjusting the volume frequency (%) of the phosphor of the phosphor layer of the sheet of the present invention and the thickness (mm) of the phosphor layer will be described. These are appropriately adjusted according to the wavelength λ (nm) or chromaticity of the excitation light source.

As shown in FIGS. 4 and 5, the present invention is based on the chromaticity CIEx and CIEy of the excitation light source, the wavelength λ or chromaticity of the excitation light source, the volume frequency (%) of the phosphor in the phosphor layer, and the thickness of the phosphor layer. Data indicating correspondence with (mm) is taken.

A light emitting device is prepared in which the wavelength λ or chromaticity of the excitation light source, the volume frequency of the phosphor, and the thickness of the phosphor layer are individually changed, and the data are associated with each other. The volume frequency (%) of the phosphor is replaced by the following mathematical formula (1). That is, the phosphor content of the phosphor layer is determined from the thickness of the sheet and the chromaticity of the light emitting device.

here,
m _phos : phosphor mass in the phosphor layer [g]
ρ _phos : phosphor density [g / cm ³ ]
m _matrix : mass of resin A in the phosphor layer [g]
ρ _matrix : density of resin A [g / cm ³ ]

  The spectral waveform of the light emitting device is measured using the wavelength λ or chromaticity of the excitation light source, the phosphor content of the phosphor layer, and the thickness of the phosphor layer as parameters. Thus, the spectral waveform is associated with the wavelength λ or chromaticity of the excitation light source, the phosphor content of the phosphor layer, and the thickness of the phosphor layer.

  For example, the wavelength of the excitation light source is 450 nm, the phosphor layers are two layers, the thickness of each layer is 0.2 mm to 0.5 mm, and each phosphor layer contains a red phosphor and a green phosphor, and the chromaticity (CIEx) , CIEy) = (0.289, 0.294) (= daylight color), the volume frequency of the green phosphor is 2.00% to 50.0%, and the volume frequency of the red phosphor is 0.400%. -5.00% is preferable. When the chromaticity is set to (CIEx, CIEy) = (0.437, 0.404) (= bulb color) with the same configuration, the volume frequency of the green phosphor is 4.00% to 40.0%, and the red fluorescence The volume frequency of the body is preferably 0.500% to 6.00%.

  The thickness of each layer of the phosphor-containing multilayer film of the present invention is preferably 0.2 mm to 0.5 mm. If the thickness of the sheet is smaller than 0.2 mm, the desired chromaticity cannot be obtained even if the volume frequency of the phosphor is increased, and the sheet production becomes difficult. When the thickness of the sheet exceeds 0.5 mm, concentration quenching occurs due to self-absorption caused by the other phosphors in the same layer that absorbs the light emitted from the phosphors in the layer, thereby reducing the total luminous flux. End up.

  A method for producing the phosphor-containing multilayer film of the present invention will be described. From a slurry obtained by kneading the sealing resin and phosphor at the above ratio and vacuum defoaming, using a known sheet forming method such as vacuum forming, pressure forming, press forming, etc., cutting method, nanoimprint method, laser fine processing A phosphor-containing multilayer film sheet can be obtained by providing a fine relief structure on the surface using an etching method or the like. By using the phosphor-containing multilayer film sheet of the present invention, the light emission luminance of the white LED can be increased, and the process of applying the phosphor is not necessary and can be simplified in manufacturing the white LED.

<Evaluation of light extraction efficiency>
An LED chip having an emission peak wavelength of 450 nm and a half width of 20 nm was mounted on a package having a light emission area of 4.5 mm ² and a depth of 0.85 mm. Thereafter, a silicone resin (KER-2500, manufactured by Shin-Etsu Chemical Co., Ltd.) having a refractive index n _D = 1.41 was potted to cure the resin. Thereafter, the chip was illuminated with a voltage of 3 V and a current of 20 mA, and the total luminous flux was measured using a total luminous flux measurement system (total luminous flux measurement (φ1000 mm) system, manufactured by Otsuka Electronics Co., Ltd.). Similarly, the total luminous flux was measured using the above-mentioned total luminous flux system even when the tip (refractive index = 2.5) was exposed to air (refractive index = 1.0) without potting the silicone resin.

  FIG. 6 shows an emission spectrum of the package when the potting is performed and an emission spectrum when the resin is not potted. When the resin was potted, the total luminous flux value was 1.36 times larger than when the resin was not potted.

  When the resin is potted, a discontinuous refractive index gap is generated at the interface between the chip and the resin and at the interface between the resin and the air layer. Light is reflected by this refractive index gap. Therefore, the present inventors provided a fine concavo-convex structure smaller than visible light (400 to 800 nm) at the interface / surface of each layer. This allows light to pass through without reflecting as if there were no interface. The present inventors have found that this can further increase the total luminous flux.

  The present invention will be illustrated more specifically with reference to examples, but the present invention is not limited by the contents described in these examples.

<Production method of sheet>
As a resin A, a phosphor is melt-kneaded with a two-part silicone resin (KER-2500, manufactured by Shin-Etsu Chemical Co., Ltd.) using a vacuum defoaming device (ARV-310, manufactured by THINKY) to prepare a phosphor paste. . Next, the paste is poured into the opening using a spacer frame having an opening of 30 mm × 30 mm and the depth adjusted. Then, it heated and hardened at 150 degreeC for 1 hour, and produced the fluorescent substance containing sheet.

<Evaluation of thickness of each layer of sheet>
[Example 1]
The red phosphor CASN is mixed with the silicone resin so that the volume frequency is 0.9% so that the chromaticity becomes (0.289, 0.294), and the thickness of the sheet becomes 0.5 mm. Thus, a phosphor-containing sheet was produced. Similarly, green phosphor β-SiAlON is mixed with the silicone resin so that the volume frequency is 5.5%, and the phosphor-containing sheet is produced by the production method so that the thickness of the sheet is 0.5 mm. did. Further, the red phosphor-containing sheet was disposed at a position close to the excitation light source, and the green phosphor-containing sheet was stacked at a position far from the excitation light source. Finally, a fine concavo-convex structure was formed on the surface where the excitation light was incident and the surface where the incident light was emitted to the outside. The pattern pitch distance of the fine concavo-convex structure shown in FIG. 11 was 0.2 μm, and the height of the convex part of the fine concavo-convex structure was 0.4 μm, which was used as a phosphor-containing multilayer film sheet.

[Comparative Example 1]
The same as Example 1 except that the thickness of the sheet was changed to 0.7 mm.

[Comparative Example 2]
The same as Example 1 except that the thickness of the sheet was changed to 1.0 mm.

[Example 2]
The volume frequency of the green phosphor β-SiAlON is 16.4%, the sheet thickness is 0.2 mm, and the fine irregularities so that the volume frequency of the red phosphor CASN is 2.3% and the sheet thickness is 0.2 mm. The same as Example 1 except that the pattern pitch distance of the structure was changed to 0.05 μm.

[Comparative Example 3]
The same as Example 2 except that the thickness of the sheet was changed to 0.1 mm.

[Comparative Example 4]
The same as Example 2 except that the thickness of the sheet was changed to 0.05 mm.

<Evaluation of sheet>
The sheet formed in each example and comparative example was placed on a blue LED jig having a peak wavelength of 450 nm, a half width of 20 nm, and a light emission intensity of 0.0123 W, the LED was turned on, and the total luminous flux measurement system (total luminous flux measurement (φ1000 mm ) System, manufactured by Otsuka Electronics Co., Ltd.) to measure the total luminous flux.

FIG. 7 shows emission spectra of Example 1, Comparative Example 1, and Comparative Example 2. Table 1 shows the total luminous fluxes of Example 1, Comparative Example 1, and Comparative Example 2.
As shown in FIG. 7 and Table 1, in Comparative Example 1 and Comparative Example 2 in which the thickness of the sheet exceeds 0.5 mm, the total luminous flux is smaller than the sheet of Example 1 which is the present embodiment, and the target chromaticity is not achieved. I understand.

FIG. 8 shows emission spectra from the phosphors of Example 2, Comparative Example 3, and Comparative Example 4. Table 1 shows the total luminous flux. In Comparative Examples 3 and 4 in which the sheet thickness was less than 0.2 mm, the target chromaticity was not achieved, and the total luminous flux was small.

<Examination of layer order of phosphor layers>
Under the same chromaticity, the one that is laminated in order from the phosphor layer containing the phosphor having the longer emission wavelength and the one that is laminated in order from the phosphor layer containing the phosphor having the shorter emission wavelength A comparison was made.

  Based on FIGS. 4 and 5, the sheet thickness is 0.5 mm, the volume frequency of the phosphor is adjusted, and the chromaticity of the light source is (0.345, 0.352) (= day white), or (0 .437, 0.404) (= bulb color), the emission spectrum and the total luminous flux were measured.

[Example 3]
CASN, which is a red phosphor, is contained at a volume frequency of 1.3% at a position close to the excitation light source, a sheet having a thickness of 0.5 mm is arranged, and β-SiAlON, which is a green phosphor, is contained at a volume frequency of 7.1%. Then, the same as Example 1 except that sheets having a thickness of 0.5 mm are laminated so that the chromaticity becomes (0.345, 0.352).

[Comparative Example 5]
The sheet containing the green phosphor β-SiAlON with a volume frequency of 5.0% was placed close to the excitation light source, and the sheet containing the red phosphor CASN with a volume frequency of 2.4% was stacked. Other than the above, the third embodiment is the same as the third embodiment.

[Example 4]
Other than changing CASN that is red phosphor to volume frequency 2.0% and β-SiAlON that is green phosphor to volume frequency 10.1% so that chromaticity becomes (0.437, 0.404). This is the same as in Example 3.

[Comparative Example 6]
Other than changing β-SiAlON, which is a green phosphor, to a volume frequency of 5.9%, and CASN, which is a red phosphor, to a volume frequency of 4.3% so that the chromaticity is (0.437, 0.404). This is the same as Comparative Example 5.

The emission spectra of Example 3 and Comparative Example 5 are shown in FIG. Example 4 and Comparative Example 6 are shown in FIG. Table 1 shows the total luminous flux values of Example 3, Example 4, Comparative Example 5, and Comparative Example 6. From this, the total luminous flux is larger in the present embodiment.

[Comparative Example 7]
Example 1 is the same as Example 1 except that the pattern pitch distance of the unevenness on the surface is 0.5 μm and the height of the convex portion is changed to 0.5 μm.

[Comparative Example 8]
The pattern pitch distance of the unevenness on the surface is 0.4 μm, and the same as Example 1 except that the height of the convex portion is changed to 0.5 μm.

[Comparative Example 9]
Example 1 is the same as Example 1 except that the pattern pitch distance of the surface irregularities is 0.5 μm and the height of the convex portion is changed to 0.4 μm.

[Comparative Example 10]
The pattern pitch distance of the unevenness on the surface is 0.04 μm, and the same as Example 1 except that the height of the convex portion is changed to 0.04 μm.

Table 1 shows total luminous fluxes of Example 1 and Comparative Examples 7 to 10. In Example 1, the total luminous flux was increased.

[Comparative Example 11]
The red phosphor CASN has a volume frequency of 1.6% and the green phosphor β-SiAlON has a volume frequency of 4.3% so that the chromaticity is (0.289, 0.294). It is the same as Example 1 except that the mixture is mixed with a silicone resin, and the red phosphor and the green phosphor coexist in the same layer having a thickness of 0.5 mm, and the single layer structure is changed.

  Table 1 shows the total luminous fluxes of Example 1 and Comparative Example 11. In Example 1, the total luminous flux was larger.

[Example 5]
CASN, which is a red phosphor, has a volume frequency of 2.0%, a sheet having a thickness of 0.5 mm, and β-SiAlON, which is a green phosphor, so that the chromaticity is (0.437, 0.404). Example 4 is the same as Example 4 except that the frequency was changed to 36.9% and the thickness was changed to 0.2 mm.

[Comparative Example 12]
The same as Example 5 except that β-SiAlON, which is a green phosphor, was changed to a volume frequency of 99.9% and a thickness of 0.1 mm.

[Comparative Example 13]
The same as Example 5 except that β-SiAlON, which is a green phosphor, was changed to a volume frequency of 4.6% and a thickness of 1.0 mm.

Table 1 shows the total luminous fluxes of Example 5, Comparative Example 12, and Comparative Example 13. In Example 5, the total luminous flux was larger.

[Example 6]
The same as Example 1 except that the resin was changed to bisphenol A type epoxy resin (trade name Epicoat 806, manufactured by Japan Epoxy Resin Co., Ltd.).

From Table 1, Example 6 had the same total luminous flux as that of Example 1.

DESCRIPTION OF SYMBOLS 1 Phosphor containing multilayer film sheet 101a Red fluorescent substance containing resin layer 101b Green fluorescent substance containing resin layer 102 Resin layer 103, 201 Red fluorescent substance 104, 202 Green fluorescent substance 203 Blue fluorescent substance 301 Sealing resin

Claims (10)

In the phosphor-containing multilayer film sheet composed of two or more layers of the resin composition mainly composed of the resin A and containing two or more kinds of phosphors including a red phosphor and a green phosphor,
It is provided to be laminated in the traveling direction of light passing through the phosphor-containing multilayer film sheet, and among the phosphor-containing multilayer film sheets, there are at least two phosphor layers containing the phosphor, There is one kind of phosphor contained in the phosphor layer, and the phosphor-containing multilayer is sequentially from a phosphor layer containing a phosphor having a long emission wavelength to a phosphor layer containing a phosphor having a short emission wavelength. The phosphors are arranged in the traveling direction of light passing through the film sheet, the volume frequency of the phosphor contained in each phosphor layer is 0.4% or more and 40% or less, and the thickness of each phosphor layer is 0. A fine concavo-convex structure having a height of 0.4 μm or less and a pattern pitch distance of 0.4 μm or less was formed on the surface on which light was incident and the surface from which the incident light was emitted to the outside. A phosphor-containing multilayer film characterized by G.   The phosphor-containing multilayer film sheet according to claim 1, wherein a pattern pitch distance of the fine uneven structure is 0.05 μm to 0.4 μm.   The phosphor-containing multilayer film sheet according to claim 1 or 2, wherein the height of the convex portion of the fine concavo-convex structure is 0.05 µm to 0.4 µm.   The phosphor-containing multilayer film sheet according to any one of claims 1 to 3, wherein a fine uneven structure is formed at an interface of each layer.   The phosphor-containing multilayer film sheet according to any one of claims 1 to 4, wherein the resin A is any one selected from an epoxy resin and a silicone resin.   Resin A is a silicone resin, The fluorescent substance containing multilayer film sheet as described in any one of Claims 1-5. The red phosphor is selected from phosphors having Eu ²⁺ as an activator and based on a crystal composed of alkaline earth silicate, alkaline earth silicate, α-SiAlON or alkaline earth silicate. The phosphor-containing multilayer film sheet according to any one of claims 1 to 6, comprising one kind of phosphor. The green phosphor has Eu ²⁺ as an activator and a green phosphor or Ce ³⁺ based on a crystal composed of alkaline earth silicate, alkaline earth silicate nitride or β-SiAlON as an activator. The phosphor-containing multilayer film sheet according to any one of claims 1 to 7, wherein the phosphor-containing multilayer sheet is a green phosphor based on a crystal composed of a garnet-type oxide or an alkaline earth metal scandate.   The phosphor-containing multilayer film sheet according to claim 1, wherein the phosphor contained in each phosphor layer is one kind. The light-emitting device using the fluorescent substance containing multilayer film sheet as described in any one of Claims 1-9.