JP2007048864A - Phosphor composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chemically stable phosphor composite material having a high energy conversion efficiency and a high mechanical strength. <P>SOLUTION: The phosphor composite material has an inorganic-material base material and a glass sintered layer, and the glass sintered layer is formed on one surface or both surfaces of the inorganic-material base material. When the composite material is irradiated with an excitation light, the inorganic-material base material has a light transmitting property to the wavelength range of the excitation light, and the glass sintered layer has a property in which a light is absorbed in the wavelength range of the excitation light, and a fluorescence is emitted having a wavelength from 380 nm to 780 nm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a phosphor composite material that converts the wavelength of light emitted from a light source into another wavelength.

  In recent years, white LEDs are expected to be applied to lighting applications as next-generation light sources that replace incandescent bulbs and fluorescent lamps.

  In LED elements that perform wavelength conversion using phosphors, phosphor powder is mixed and molded into an organic binder resin (mold resin) that seals the light emitting surface of the LED chip, and part or all of the light emitted from the LED chip is molded. Is converted into a desired wavelength.

  However, since the LED element is molded by mixing phosphor powder with an organic binder resin that seals the light emitting surface of the LED chip, high-power short-wavelength light in the blue to ultraviolet region, or phosphor The resin constituting the LED element is deteriorated by heat generation or heat of the LED chip, causing discoloration. As a result, there is a problem in that the emission intensity is lowered and the color shift occurs and the life is shortened.

Therefore, it has been proposed to fix phosphor powder with glass instead of resin. (For example, Patent Document 1)
JP 2003-258308 A

  The phosphor composite material disclosed in Patent Document 1 is produced by firing a mixed powder of glass powder and phosphor powder. The phosphor composite material thus produced has a feature that the glass as a base material is not deteriorated by heat or irradiation light.

  However, the phosphor composite material disclosed in Patent Document 1 is a material obtained by firing a mixture of glass powder and inorganic phosphor powder, and therefore has low mechanical strength. If the thickness of the phosphor composite material is increased in order to increase the mechanical strength, there arises a problem that the energy conversion efficiency is lowered.

  An object of the present invention is to provide a phosphor composite material that is chemically stable, has high energy conversion efficiency, and has high mechanical strength.

  The phosphor composite material of the present invention is a phosphor composite material having an inorganic material substrate and a glass sintered layer, wherein a glass sintered layer is formed on one or both sides of the inorganic material substrate, and excitation light , The inorganic material substrate has translucency with respect to the wavelength region of excitation light, and the glass sintered layer absorbs light in the wavelength region of excitation light and emits fluorescence with a wavelength of 380 to 780 nm. It has the property to emit.

  Since the phosphor composite material of the present invention is formed only from the inorganic material substrate and the inorganic material of the glass sintered layer, it is chemically stable and can suppress the deterioration of the emission intensity and the shortening of the lifetime. In addition, since the glass sintered layer is formed on the surface of the inorganic material substrate, high mechanical strength can be obtained even if the glass sintered layer is thin. Therefore, a phosphor composite material with high energy conversion efficiency can be obtained. Therefore, it is suitable as a member used as a light emitting device such as an illumination, a display, or a headlight of an automobile or the like.

  In phosphor materials, organic materials are included in the phosphor material in order to suppress deterioration of the light emission intensity and shortening of the lifetime caused by chemically stable and high output light and heat of the phosphor and LED chip. Design so that there is no. The phosphor composite material of the present invention is formed only from an inorganic material substrate and an inorganic material of a glass sintered layer. For this reason, it is possible to suppress deterioration of the light emission intensity and shortening of the life caused by chemically stable, high output light, and heat generation of the phosphor and the LED chip.

  Moreover, although the mechanical strength is low only by the glass sintered layer formed by firing the glass powder and the phosphor powder, the phosphor composite material of the present invention is an inorganic material having a higher mechanical strength than the glass sintered layer. A glass sintered layer is formed on the surface of the substrate. Therefore, high mechanical strength can be obtained without increasing the thickness of the glass sintered layer.

  Furthermore, since the inorganic material substrate has translucency with respect to the wavelength range of the excitation light, the excitation light can reach the glass sintered layer formed on the surface of the inorganic material substrate and emit fluorescence.

  The excitation light is preferably a light beam having a wavelength of 300 to 500 nm. The reason is that there are many types of inorganic phosphor powders that emit fluorescence when irradiated with light in this wavelength range, and it is easy to obtain members.

  In the phosphor composite material of the present invention, the inorganic material substrate and the glass sintered layer are preferably in close contact by fusing and integrating the glass sintered layer onto the inorganic material substrate. By adopting a structure in which no space is provided between the inorganic material substrate and the glass sintered layer, it is possible to suppress a decrease in light emission intensity and to improve mechanical strength. Further, it is not necessary to use a resin such as an adhesive that causes discoloration.

  In order to prevent peeling of the glass sintered layer from the inorganic material substrate, α1−α2 ≦ ± 1 ppm / when α1 is the thermal expansion coefficient of the inorganic material substrate and α2 is the thermal expansion coefficient of the glass sintered layer. It is preferable to make it into ° C. When it is out of this range, it becomes easy to peel off. Preferably, α1−α2 ≦ ± 0.8 ppm / ° C.

  In addition, it is preferable to use what has translucency with respect to the wavelength range of excitation light as an inorganic material base material which comprises the fluorescent substance composite material of this invention, specifically, in the wavelength range of excitation light. The total transmittance including diffuse transmittance is preferably 50% or more (preferably 60% or more, more preferably 70% or more). This is because when the total transmittance in the wavelength region of the excitation light is lowered, the excitation light is difficult to reach the glass sintered layer, and as a result, the luminous efficiency of the phosphor composite material is lowered.

  The inorganic fluorescent material preferably has a thermal conductivity at 25 ° C. of 10 W / m · K or more (preferably 15 W / m · K or more, more preferably 20 W / m · K or more). The reason for this is that when the thermal conductivity of the inorganic material substrate is increased, the heat dissipation effect is increased, and the heat generated from the phosphor and the LED chip can be released, and the deterioration of the phosphor and the LED chip due to heat can be suppressed. This is because it can.

  Moreover, it is preferable that an inorganic material base material is plate shape. The reason is that if the inorganic material substrate is plate-shaped, a glass sintered layer can be easily formed on the inorganic material substrate.

  The inorganic material substrate preferably has a thickness of 0.1 to 10.0 mm. The reason is that if the thickness of the inorganic material substrate becomes too thin, the mechanical strength of the phosphor composite material tends to be lowered. On the other hand, if the wall thickness is too thick, the excitation light tends to be difficult to transmit, and as a result, the light emission efficiency of the phosphor composite material tends to decrease.

The inorganic material substrate is not particularly limited as long as it is a material having translucency with respect to the wavelength range of excitation light. Glass, Al ₂ O ₃ , MgO, ZrO ₂ , Y ₂ O ₃ translucent ceramic, sapphire single crystal, or the like can be used. In order to suppress deterioration due to heat, it is preferable to use any one of Al ₂ O ₃ , MgO, ZrO ₂ , Y ₂ O ₃ and sapphire single crystal having a large thermal conductivity.

  Moreover, as a glass sintering layer which comprises the fluorescent substance composite material of this invention, the light of the wavelength range of excitation light is absorbed, The fluorescence of the light of wavelength 380-780 nm, especially blue (wavelength 440-480 nm), green It is preferable to use a material having a property of emitting fluorescence (wavelength 500 to 550 nm), yellow (wavelength 550 to 600 nm), and red (wavelength 600 to 780 nm).

  In order to obtain a sintered glass layer having the above properties, a mixture containing glass powder and inorganic phosphor powder may be fired. Since such a glass sintered layer has a structure in which an inorganic phosphor is dispersed in glass, it is chemically stable and can suppress discoloration even when exposed to high output light for a long period of time.

  The inorganic phosphor powder contained in the sintered glass layer can be used as long as it is generally available in the market. Oxides, nitrides, oxynitrides, sulfides, oxysulfides, halides, halophosphorus Some are made of acid chlorides. Among the above-described inorganic phosphors, those having an excitation band at a wavelength of 300 to 500 nm and having an emission peak at a wavelength of 380 to 780 nm, particularly those emitting light in blue, green and red are preferably used.

Examples of phosphors that emit blue fluorescence when irradiated with excitation light in the ultraviolet region with a wavelength of 300 to 440 nm include Sr ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , (Sr, Ba) MgAl ₁₀ O ₁₇ : Eu ²⁺ , (Sr, Ba) ₃ MgSi ₂ O ₈ : Eu ²⁺ can be used.

Examples of phosphors that emit green fluorescence when irradiated with excitation light in the ultraviolet region with a wavelength of 300 to 440 nm include SrAl ₂ O ₄ : Eu ²⁺ , SrGa ₂ S ₄ : Eu ²⁺ , SrBaSiO ₄ : Eu ²⁺ , CdS: In, CaS: Ce ³⁺ , Y ₃ (Al, Gd) ₅ O ₁₂ : Ce ²⁺ , Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce ³⁺ , SrSiOn: Eu ²⁺ , ZnS: Al ³⁺ , Cu ⁺ , CaS: Sn ²⁺ , CaS: Sn ²⁺ , F, CaSO ₄ : Ce ³⁺ , Mn ²⁺ , LiAlO ₂ : Mn ²⁺ , BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ²⁺ , ZnS: Cu ^{+ _{, Cl -, Ca 3 WO 6}} : U, Ca 3 SiO 4 Cl 2: Eu 2+, Sr x Ba y Cl z Al 2 O 4-z / 2: Ce 3+, Mn 2+ (X: 0.2 , Y: 0.7, Z: 1.1 ), Ba 2 MgSi 2 O 7: Eu 2+, Ba 2 SiO 4: Eu 2+, Ba 2 Li 2 S ^{_{2 O 7: Eu 2+, ZnO}} : S, ZnO: Zn, Ca 2 Ba 3 (PO 4) 3 Cl: Eu 2+, BaAl 2 O 4: Eu 2+ can be used.

As phosphors emitting green fluorescence when irradiated with blue excitation light having a wavelength of 440 to 480 nm, SrAl ₂ O ₄ : Eu ²⁺ , SrGa ₂ S ₄ : Eu ²⁺ , SrBaSiO ₄ : Eu ²⁺ , CdS: In CaS: Ce ³⁺ , Y ₃ (Al, Gd) ₅ O ₁₂ : Ce ²⁺ , Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce ³⁺ , SrSiO _N : Eu ²⁺ can be used.

Examples of phosphors that emit yellow fluorescence when irradiated with excitation light in the ultraviolet region with a wavelength of 300 to 440 nm include ZnS: Eu ²⁺ , Ba ₅ (PO ₄ ) ₃ Cl: U, Sr ₃ WO ₆ : U, CaGa ₂ S. ₄ : Eu ²⁺ , SrSO ₄ : Eu ²⁺ , Mn ²⁺ , ZnS: P, ZnS: P ³⁻ , Cl ⁻ ZnS: Mn ²⁺ can be used.

As phosphors that emit yellow fluorescence when irradiated with blue excitation light having a wavelength of 440 to 480 nm, Y ₃ (Al, Gd) ₅ O ₁₂ : Ce ²⁺ , Ba ₅ (PO ₄ ) ₃ Cl: U, CaGa ₂ S ₄ : Eu ²⁺ can be used.

Examples of phosphors that emit red fluorescence when irradiated with excitation light in the ultraviolet region with a wavelength of 300 to 440 nm include CaS: Yb ²⁺ , Cl, Gd ₃ GA ₄ O ₁₂ : Cr ³⁺ , CaGa ₂ S ₄ : Mn ^2+. Na (Mg, Mn) ₂ LiSi ₄ O ₁₀ F ₂ : Mn, ZnS: Sn ²⁺ , Y ₃ Al ₅ O ₁₂ : Cr ³⁺ , SrB ₈ O ₁₃ : Sm ²⁺ , MgSr ₃ Si ₂ O ₈ : Eu ²⁺ , Mn ²⁺ , α-SrO · 3B ₂ O ₃ : Sm ²⁺ , ZnS—CdS, ZnSe: Cu ⁺ , Cl, ZnGa ₂ S ₄ : Mn ²⁺ , ZnO: Bi ³⁺ , BaS: Au , K, ZnS: Pb ²⁺ , ZnS: Sn ²⁺ , Li ⁺ , ZnS: Pb, Cu, CaTiO ₃ : Pr ³⁺ , CaTiO ₃ : Eu ³⁺ , Y ₂ O ₃ : Eu ³⁺ , (Y, Gd) ₂ O ₃ : Eu ³⁺ , CaS: Pb ²⁺ , Mn ²⁺ , YPO ₄ : Eu ³⁺ , Ca ₂ MgSi ₂ O ₇ : Eu ^{2 +} , Mn ²⁺ , Y (P, V) O ₄ : Eu ³⁺ , Y ₂ O ₂ S: Eu ³⁺ , SrAl ₄ O ₇ : Eu ³⁺ , CaYAlO ₄ : Eu ³⁺ , LaO ₂ S: Eu ³⁺ , LiW ₂ O ₈ : Eu ³⁺ , Sm ³⁺ , (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ , Mn ²⁺ , Ba ₃ MgSi ₂ O ₈ : Eu ²⁺ , Mn ²⁺
Phosphors that emit red fluorescence when irradiated with blue excitation light having a wavelength of 440 to 480 nm include ZnS: Mn ²⁺ , Te ²⁺ , Mg ₂ TiO ₄ : Mn ⁴⁺ , K ₂ SiF ₆ : Mn ⁴⁺ , SrS: Eu ²⁺ , Na _1.23 K _0.42 Eu _0.12 TiSi ₄ O ₁₁ , Na _1.23 K _0.42 Eu _0.12 TiSi ₅ O ₁₃ : Eu ³⁺ , CdS: In, Te, CaAlSiN ₃ : Eu ²⁺ , CaSiN ₃ : Eu ^{2 +} , (Ca, Sr) ₂ Si ₅ N ₈ : Eu ²⁺ , Eu ₂ W ₂ O ₇ can be used.

  A plurality of inorganic phosphor powders may be mixed and used in accordance with the wavelength range of excitation light and the color desired to emit light. For example, in order to obtain white light by irradiating ultraviolet excitation light, phosphors emitting blue, green, and red fluorescence may be mixed and used.

  Some of the above inorganic phosphor powders react with glass by heating during sintering and cause abnormal reactions such as foaming and discoloration. Become. However, even such inorganic phosphor powders can be used by optimizing the firing temperature and glass composition.

The glass powder used when producing the glass sintered layer has a role as a medium for stably holding the inorganic phosphor. Further, since the color tone of the sintered body varies depending on the composition system of the glass powder and the reactivity with the inorganic phosphor varies, it is necessary to select the composition of the glass powder in consideration of various conditions. It is also important to determine the amount of inorganic phosphor added suitable for the glass composition and the thickness of the member. The glass powder is not particularly limited as long as it does not easily react with the inorganic phosphor. For example, SiO ₂ —B ₂ O ₃ —RO (RO represents MgO, CaO, SrO, BaO). system glass, SiO ₂ -B ₂ O ₃ based _{glass, SiO 2 -B 2 O 3 -R} 2 O (R 2 O represents _{Li 2 O, Na 2 O,} K 2 O) -based glass, SiO ₂ -B ₂ O ₃ —Al ₂ O ₃ glass and SiO ₂ —B ₂ O ₃ —ZnO glass can be used. Among these, it is preferable to use SiO ₂ —B ₂ O ₃ —RO-based glass that hardly reacts with the inorganic phosphor during firing.

The composition range of the SiO ₂ —B ₂ O ₃ —RO-based glass is SiO ₂ 30 to 70%, B ₂ O ₃ 1 to 15%, MgO 0 to 10%, CaO 0 to 25%, SrO 0 in terms of mole percentage. ~10%, BaO 5~40%, RO 10~45%, Al 2 O 3 0~20%, is preferably 0% ZnO. The reason for determining the above range is as follows.

SiO ₂ is a component that forms a network of glass. When the content is less than 30 mol%, chemical durability tends to deteriorate. On the other hand, if it exceeds 70 mol%, the sintering temperature becomes high, and the phosphor tends to deteriorate. A more preferred range of SiO ₂ is 45 to 65%.

B ₂ O ₃ is a component that significantly improves the meltability by lowering the melting temperature of the glass. When the content is less than 1 mol%, it is difficult to obtain the effect. On the other hand, when it exceeds 15 mol%, chemical durability tends to deteriorate. A more preferable range of B ₂ O ₃ is 2 to 10%.

  MgO is a component that improves the meltability by lowering the melting temperature of the glass. When the content exceeds 10 mol%, chemical durability tends to deteriorate. A more preferable range of MgO is 0 to 5%.

  CaO is a component that improves the meltability by lowering the melting temperature of the glass. When the content is more than 25 mol%, chemical durability tends to deteriorate. A more preferable range of CaO is 3 to 20%.

  SrO is a component that improves the meltability by lowering the melting temperature of the glass. When the content exceeds 10 mol%, chemical durability tends to deteriorate. A more preferable range of SrO is 0 to 5%.

  BaO is a component that improves the meltability by lowering the melting temperature of the glass and suppresses the reaction with the phosphor. When the content is less than 5 mol%, the reaction suppression effect with the phosphor tends to be reduced. On the other hand, when it exceeds 40 mol%, chemical durability tends to deteriorate. A more preferable range of BaO is 10 to 35%.

  In order to improve the meltability of the glass without deteriorating the chemical durability, it is preferable that the total amount of RO of MgO, CaO, SrO and BaO is 10 to 45 mol%. If the RO content is less than 10 mol%, it is difficult to obtain the effect of improving the meltability. On the other hand, when it exceeds 45 mol%, chemical durability tends to deteriorate. A more preferable range of RO is 11 to 40%.

Al ₂ O ₃ is a component that improves chemical durability. When the content exceeds 20 mol%, the meltability of the glass tends to deteriorate. A more preferable range of Al ₂ O ₃ is 2 to 15%.

  ZnO is a component that improves the meltability by lowering the melting temperature of the glass. When the content exceeds 10 mol%, chemical durability tends to deteriorate. A more preferable range of ZnO is 1 to 7%.

In addition to the above components, various components can be added as long as the gist of the present invention is not impaired. For example, an alkali metal oxide, P ₂ O ₅ , La ₂ O ₃ or the like may be added.

  Moreover, it is desirable to use a glass powder having an average particle size of 1 to 100 μm. If the average particle size of the glass powder is reduced, the cost is likely to increase. On the other hand, if the average particle size is increased, excitation light is not efficiently irradiated onto the phosphor in the glass sintered layer.

  The luminous efficiency of the sintered glass layer varies depending on the type and content of phosphor particles dispersed in the glass and the thickness of the sintered glass layer. The phosphor content and the thickness of the sintered glass layer may be adjusted to optimize the energy conversion efficiency. However, if the phosphor is too much, it becomes difficult to sinter and the porosity increases. There arises a problem that it becomes difficult to efficiently irradiate the phosphor with the excitation light. On the other hand, if the amount is too small, it becomes difficult to emit light sufficiently. Therefore, the mixing ratio of the glass powder and the inorganic phosphor powder is 70 to 99.99% (preferably 80 to 99.95%, more preferably 85 to 99.92%) of the glass powder in terms of mass ratio, inorganic. It is preferable to adjust the phosphor powder to a range of 0.01 to 30% (preferably 0.5 to 20%, more preferably 0.8 to 15%).

  Moreover, in order to obtain said glass sintered layer, the mixture which added the organic solvent and binder resin to said glass powder and inorganic fluorescent substance powder is baked in the form of a paste, a green sheet, etc., for example. Can be obtained at

  A method for obtaining a glass sintered layer using a paste will be described.

  A paste uses a binder, a plasticizer, a solvent, etc. with the glass powder and inorganic fluorescent substance powder which were mentioned above.

  As a ratio of the glass powder and the inorganic phosphor powder in the entire paste, about 30 to 90% by mass is common.

  A binder is a component which increases the film | membrane intensity | strength after drying and provides a softness | flexibility, and the content is about 0.1-20 mass% in general. As the binder, polybutyl methacrylate, polyvinyl butyral, polymethyl methacrylate, polyethyl methacrylate, ethyl cellulose, nitrocellulose and the like can be used, and these are used alone or in combination.

  The plasticizer is a component that controls the drying speed and imparts flexibility to the dry film, and the content thereof is generally about 0 to 10% by mass. As the plasticizer, dibutyl phthalate, butyl benzyl phthalate, dioctyl phthalate, diisooctyl phthalate, dicapryl phthalate, dibutyl phthalate and the like can be used, and these are used alone or in combination.

  The solvent is a material for pasting the material, and its content is generally about 10 to 50% by mass. As the solvent, terpineol, isoamyl acetate, toluene, methyl ethyl ketone, diethylene glycol monobutyl ether acetate, 2,2,4-trimethyl-1,3-pentadiol monoisobutyrate and the like can be used alone or in combination.

  The paste can be prepared by preparing glass powder, inorganic phosphor powder, binder, plasticizer, solvent and the like and kneading them at a predetermined ratio.

  In order to directly form a glass sintered layer on an inorganic material substrate using such a paste, the paste is applied on the inorganic material substrate using a screen printing method, a batch coating method, or the like, and a predetermined film is formed. After forming a thick coating layer, it can be dried and fired at 700 to 1000 ° C. to obtain a predetermined glass sintered layer.

  Next, a method for obtaining a sintered glass layer using a green sheet will be described.

  A green sheet uses a binder, a plasticizer, a solvent, etc. with the said glass powder and inorganic fluorescent substance powder.

  The ratio of the glass powder and the inorganic phosphor powder in the green sheet is generally about 50 to 80% by mass.

  As the binder, plasticizer, and solvent, the same binder, plasticizer, and solvent as those used in the preparation of the paste can be used, and the mixing ratio of the binder is 0.1 to 30 mass. The mixing ratio of the plasticizer is generally about 0 to 10% by mass, and the mixing ratio of the solvent is generally about 1 to 40% by mass.

  As a general method for producing a green sheet, the above glass powder, inorganic phosphor powder, binder, plasticizer, etc. are prepared, and a solvent is added to these to form a slurry. A sheet is formed on a film of terephthalate (PET) or the like. Subsequently, after forming the sheet, it is possible to obtain a green sheet by removing the organic solvent by drying.

  In order to directly form a glass sintered layer on an inorganic material substrate using the green sheet obtained as described above, a green sheet is laminated on an inorganic material substrate and thermocompression bonded to form a coating layer. After that, the sintered glass layer can be obtained by firing in the same manner as in the case of the paste described above.

  In addition, although the example which uses a paste or a green sheet was given as a manufacturing method of a glass sintered layer, the glass sintered layer used for the fluorescent substance composite material of this invention is not limited to this, Generally ceramics Various methods used for manufacturing can be applied.

  The glass sintered layer preferably has a thickness of 0.01 to 1.0 mm. If the thickness of the glass sintered layer is too thin, it becomes difficult for the glass sintered layer to emit fluorescence. On the other hand, if the wall thickness is too thick, the energy conversion efficiency tends to decrease.

  Next, a preferred method for producing the phosphor composite material of the present invention will be described.

  First, a paste or green sheet for obtaining the above-mentioned inorganic material substrate and a glass sintered layer is prepared. Next, a paste is applied to the surface of the inorganic material substrate using a screen printing method, a batch coating method, or the like, or a green sheet is laminated, and a glass layer is formed on the surface of the inorganic material substrate. Thereafter, the inorganic material substrate on which the glass layer is formed is fired. By doing in this way, the fluorescent substance composite material of this invention can be obtained.

  In addition, when producing the fluorescent substance composite material of this invention using a paste, you may form what contains several inorganic fluorescent substance powder on the inorganic material base-material surface.

  Moreover, when producing the phosphor composite material of the present invention using a green sheet, one green sheet containing a plurality of inorganic phosphor powders may be formed on the surface of the inorganic material substrate, A sheet produced and laminated may be formed on the surface of the inorganic material substrate.

  In addition, the phosphor composite material of the present invention is a phosphor composite material obtained by firing an inorganic material base material on which a glass layer is formed, and is cut and polished to have an arbitrary shape, for example, a disc shape, a column shape, You may process into shapes, such as a rod shape.

  In addition, it is preferable that it is 700-1000 degreeC as temperature which bakes the inorganic material base material in which the glass layer was formed. The reason is that at a temperature lower than 700 ° C., the glass sintered layer is easily peeled off from the inorganic material substrate, or a dense glass sintered layer is difficult to obtain. It becomes difficult to obtain a phosphor composite material that emits desired light. On the other hand, at a temperature higher than 1000 ° C., it becomes difficult to obtain a phosphor composite material that emits desired light due to the reaction between the glass in the glass sintered layer and the inorganic phosphor.

  Hereinafter, the phosphor composite material of the present invention will be described in detail based on examples.

  First, a paste for obtaining an inorganic material substrate and a glass sintered layer was prepared.

  As for the inorganic material substrate, translucent alumina having a size of 50.0 × 50.0 × 1.0 mm, a transmittance of 93% or more at a wavelength of 300 to 500 nm, and a thermal conductivity of 33 W / m · K at 25 ° C. A ceramic substrate was used.

  In addition, about the transmittance | permeability, the total transmittance in wavelength 300-500 nm was measured with the spectrophotometer which attached the integrating sphere. Moreover, about thermal conductivity, the value in 25 degreeC was measured based on JISR2616.

  About the paste for obtaining a glass sintered layer, it produced as follows.

A glass raw material prepared to have a composition containing 60% SiO ₂ , 5% B ₂ O ₃ , 10% CaO, 15% BaO, 5% Al ₂ O _{3 and} 5% ZnO in a mole percentage is put in a platinum crucible. A uniform glass was obtained by melting at 1400 ° C. for 2 hours. Next, this was pulverized with alumina balls and classified to obtain glass powder having an average particle size of 2.5 μm. Next, inorganic phosphor powder was added to the produced glass powder at a mass ratio of 90:10 and mixed to produce a mixed powder. The inorganic phosphor powder emits blue fluorescence when irradiated with ultraviolet excitation light having a wavelength of 300 to 440 nm. Sr ₅ (PO ₄ ) Cl ₃ : Eu ³⁺ (average particle size: 8 μm), green fluorescence ZnS: Al ³⁺ , Cu ⁺ (average particle size: 8 μm) emitting red, Y ₂ O ₂ S: Eu ³⁺ (average particle size: 8 μm) emitting red fluorescence in a mass ratio of 10:10:80 What was mixed with was used. Next, 6% by mass of ethyl cellulose as a binder and 90% by mass of terpineol as a solvent were added to the prepared mixed powder 100 and mixed to prepare a paste.

  The phosphor composite material was produced as follows.

  The paste produced by the above method was applied to the surface of the translucent alumina ceramic substrate by a batch coating method to form a glass layer (thickness 50 μm). Next, the translucent alumina ceramic substrate coated with the glass layer was degreased at 300 ° C. for 1 hour and baked at 850 ° C. for 20 minutes to produce a phosphor composite material.

  When the thickness of the phosphor composite material thus obtained was measured using a micrometer, it was 1040 μm, and the thickness of the sintered glass layer was 40 μm. Further, when the excitation light and the fluorescence spectrum were measured using a fluorescence spectrophotometer, the excitation spectrum of the ultraviolet light having a center near the wavelength of 365 nm, the blue fluorescence spectrum having the center near the wavelength of 450 nm, and the wavelength near 530 nm. A green fluorescence spectrum having a center and a red fluorescence spectrum having a center near a wavelength of 620 nm were observed. Further, when light emitted from the ultraviolet light emitting diode having a peak at a wavelength of 365 nm from the translucent alumina ceramic substrate side and emitted from the glass sintered layer side was measured using a chromaticity meter, x = 0 in CIE coordinates. .379, y = 0.390 white light was obtained. Furthermore, when the mechanical strength of the phosphor composite material was measured by the above method, it was 250 MPa. In addition, about mechanical strength, it calculated | required by the 3 point | piece bending test based on JISR1601.

  For comparison, only a glass sintered layer (thickness 40 μm) was produced using the paste produced by the above method, and the mechanical strength was measured by the same method as described above, and it was 43 MPa.

  The glass sintered layer was formed by applying the paste prepared by the above method onto the porous mullite ceramic substrate by a batch coating method to form a glass layer (thickness 50 μm), degreased at 300 ° C. for 1 hour, and 20 at 850 ° C. After calcination, the mullite substrate was removed by cooling.

  First, a green sheet for obtaining an inorganic material substrate and a glass sintered layer was prepared.

  As for the inorganic material substrate, a sapphire single crystal substrate having a size of 50.0 × 50.0 × 1.2 mm, a transmittance of 93% or more at a wavelength of 300 to 500 nm, and a thermal conductivity of 41 W / m · K at 25 ° C. Was used. The transmittance and thermal conductivity were obtained by the same method as in Example 1.

  About the green sheet for obtaining a glass sintered layer, it produced as follows.

Y ₃ Al ₅ O ₁₂ (YAG) (average particle diameter: 8 μm) as an inorganic phosphor powder was added to the glass powder prepared in Example 1 at a mass ratio of 95: 5, mixed and mixed. A powder was prepared. Next, 12% by mass of polyvinyl butyral resin as a binder, 3% by mass of dibutyl phthalate as a plasticizer, and 40% by mass of toluene as a solvent were added to the prepared mixed powder 100 and mixed to prepare a slurry. . Subsequently, the slurry was formed into a sheet on a PET film by the doctor blade method and dried to obtain a green sheet having a thickness of 50 μm.

  The phosphor composite material was produced as follows.

  The green sheet produced by the above method is laminated on the surface of the sapphire single crystal substrate and integrated by thermocompression bonding to produce a laminate, degreased at 400 ° C. for 1 hour, baked at 900 ° C. for 20 minutes, and cooled. Thus, a phosphor composite material was produced.

  When the excitation light and the fluorescence spectrum of the phosphor composite material thus obtained were measured using a fluorescence spectrophotometer, a blue excitation spectrum having a center near a wavelength of 465 nm and a center near a wavelength of 560 nm were obtained. A yellow fluorescence spectrum was observed. In addition, when light emitted from a blue light emitting diode having a peak at a wavelength of 465 nm from the sapphire single crystal substrate side and emitted from the glass sintered layer side was measured using a chromaticity meter, x = 0.280 in CIE coordinates. , Y = 0.318 white light was obtained. Furthermore, when the mechanical strength of the phosphor composite material was measured by the same method as in Example 1, it was 265 MPa.

  For comparison, only a sintered glass layer (thickness: 40 μm) was produced using the green sheet produced by the above method, and the mechanical strength was measured by the same method as described above.

  The glass sintered layer is prepared by laminating the green sheet (thickness 50 μm) produced by the above method on an alumina ceramic green sheet substrate and integrating by thermocompression bonding, and then degreasing at 400 ° C. for 1 hour. After baking at 900 degreeC for 20 minutes, it cooled and obtained by removing an alumina ceramic sheet.

  The phosphor composite material of the present invention is not limited to LED applications, and can be used for a material that emits high-power excitation light such as a laser diode.

It is explanatory drawing which shows the fluorescent substance composite material which consists of an inorganic material base material and a glass sintered layer.

Explanation of symbols

1 Inorganic material substrate 2 Crystallized glass

Claims (14)

  A phosphor composite material having an inorganic material substrate and a glass sintered layer, wherein the inorganic material substrate has a glass sintered layer formed on one side or both sides thereof, and is irradiated with excitation light. The material has translucency with respect to the wavelength region of excitation light, and the glass sintered layer has a property of absorbing light in the wavelength region of excitation light and emitting fluorescence with a wavelength of 380 to 780 nm. Phosphor composite material.   2. The phosphor composite material according to claim 1, which is excited by light having a wavelength of 300 to 500 nm.   The phosphor composite material according to claim 1 or 2, wherein the inorganic material substrate and the glass sintered layer are in close contact with each other by fusing the glass sintered layer to the surface of the inorganic material substrate.   The α1-α2 ≦ ± 1 ppm / ° C., where α1 is the thermal expansion coefficient of the inorganic material substrate and α2 is the thermal expansion coefficient of the glass sintered layer. Phosphor composite material.   The phosphor composite material according to any one of claims 1 to 4, wherein the inorganic material substrate has a transmittance of 50% or more in a wavelength range of excitation light.   The phosphor composite material according to claim 1, wherein the inorganic material substrate has a thermal conductivity of 10 W / m · K or more at 25 ° C.   The phosphor composite material according to claim 1, wherein the inorganic material substrate has a plate shape and a thickness of 0.1 to 10.0 mm. The inorganic material substrate is made of any one selected from the group consisting of Al ₂ O ₃ , MgO, ZrO ₂ , Y ₂ O _3, and sapphire single crystal, according to claim 1. Phosphor composite material.   The phosphor composite material according to any one of claims 1 to 4, wherein the glass sintered layer is formed by firing a mixture containing glass powder and inorganic phosphor powder.   The phosphor composite material according to claim 9, wherein the inorganic phosphor powder has an excitation band at a wavelength of 300 to 500 nm and an emission peak at a wavelength of 380 to 780 nm. Glass powder, in mole _{percent, SiO 2 30~70%, B 2} O 3 1~15%, 0~10% MgO, CaO 0~25%, SrO 0~10%, BaO 5~40%, RO ( The phosphor composite material according to claim 9, wherein RO represents MgO, CaO, SrO, BaO), 10 to 45%, Al ₂ O ₃ 0 to 20%, ZnO 0 to 10%.   The phosphor composite material according to claim 9, wherein the mixture is in a range of 70 to 99.99% glass powder and 0.01 to 30% inorganic phosphor powder in terms of mass ratio.   The glass sintered layer is formed by firing a paste or green sheet containing glass powder, inorganic phosphor powder, organic solvent and binder resin, or any one of claims 1 to 4, 9 and 10. Phosphor composite material.   The phosphor composite material according to claim 1, wherein the glass sintered layer has a thickness of 0.01 to 1.0 mm.