JP2012052018A - Phosphor-containing composition and wavelength conversion member obtained by firing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor-containing composition for producing a wavelength conversion member which comprises inorganic powder including glass powder and inorganic phosphor powder and an organic resin, in which the organic resin is hard to remain after firing, and which can produce a wavelength conversion member having excellent emission intensity.SOLUTION: The phosphor-containing composition comprises: the inorganic powder including glass powder and inorganic phosphor powder; and a polyalkylene carbonate-based resin. The wavelength conversion member is obtained by firing the same.

Description

  The present invention relates to a phosphor-containing composition suitable for producing a wavelength conversion member used for white LEDs and the like, and a wavelength conversion member formed by firing the phosphor-containing composition.

  White LEDs have advantages such as low power consumption, mercury-free, and long life, and are applied to general lighting, liquid crystal backlights, headlamps, and the like as next-generation light sources that replace incandescent bulbs and fluorescent lamps. The white LED has a configuration in which, for example, a light emitting surface of an LED chip is molded with an organic binder resin containing an inorganic phosphor powder. When excitation light emitted from the LED chip passes through this mold part, all of the excitation light is absorbed by the inorganic phosphor powder and wavelength-converted, or part of the excitation light is absorbed by the inorganic phosphor powder. Then, the wavelength-converted light and the transmitted excitation light are combined to emit desired light.

  However, there is a problem that the mold resin constituting the LED element is deteriorated by high-power short-wavelength light in the blue to ultraviolet region, and causes discoloration. In order to solve this problem, inorganic powder containing a lead-free glass powder having a softening point of 500 ° C. or higher and an inorganic phosphor powder is baked at a temperature equal to or higher than the softening point of the glass powder, so that an inorganic substance is contained in the glass matrix. A wavelength conversion member in which phosphor powder is dispersed has been proposed (for example, see Patent Document 1). The wavelength conversion member disclosed in Patent Document 1 is chemically stable because the inorganic phosphor powder is dispersed in glass, which is an inorganic material, and is exposed to high-power excitation light for a long time. However, it has the characteristic that there is little discoloration.

  The wavelength conversion member described in Patent Document 1 is pre-molded with inorganic powder containing glass powder and inorganic phosphor powder using a mold having a desired shape, and then fired at a temperature equal to or higher than the softening point of the glass powder. It is produced by this.

JP 2003-258308 A

  In recent years, with the diversification of applications, there is a demand for wavelength conversion members having complicated shapes (eg, spherical, hemispherical, meniscus lens, box, conical, thin plate, etc.) other than the conventional disk shape and rectangular parallelepiped shape. ing. In order to produce a wavelength conversion member having such a complicated shape with high dimensional accuracy, it is effective to granulate the raw material powder into a granular shape and make the powder particle size uniform, for example. At this time, an organic resin is added to the raw inorganic powder, but the wavelength conversion member obtained by firing the raw inorganic powder has a problem in that the emission intensity is inferior.

  Therefore, the present invention is a phosphor-containing composition for producing a wavelength conversion member, which contains an inorganic powder containing glass powder and an inorganic phosphor powder, and an organic resin, and has a superior wavelength conversion. It aims at providing the fluorescent substance containing composition which can produce a member.

  As a result of intensive studies, the present inventor uses a specific organic resin that can be thermally decomposed at a low temperature in a phosphor-containing composition containing an inorganic powder and an organic resin containing glass powder and an inorganic phosphor powder. The present inventors have found that the above problems can be solved, and propose the present invention.

  That is, the present invention relates to a phosphor-containing composition comprising an inorganic powder containing glass powder and an inorganic phosphor powder, and a polyalkylene carbonate resin.

  Since the phosphor-containing composition of the present invention comprises a glass powder and an inorganic phosphor powder, in the wavelength conversion member formed by firing the phosphor-containing composition, the inorganic phosphor is contained in the glass matrix. It is easy to uniformly disperse the powder. Moreover, since the composition contains an organic resin, it can be easily granulated. Here, since the polyalkylene carbonate-based resin used as the organic resin in the present invention decomposes at a relatively low temperature of 250 to 300 ° C., the wavelength conversion member excellent in emission intensity because the carbon component hardly remains after firing. Can be produced.

  Secondly, the phosphor-containing composition of the present invention is characterized in that the polyalkylene carbonate resin is a polyethylene carbonate resin or a polypropylene carbonate resin.

  Thirdly, the phosphor-containing composition of the present invention is characterized by containing 0.1 to 20 parts by mass of a polyalkylene carbonate-based resin with respect to 100 parts by mass of the inorganic powder.

Fourthly, the phosphor-containing composition of the present invention is characterized in that the glass powder is SnO—P ₂ O ₅ glass.

Since the SnO—P ₂ O ₅ glass has a relatively low softening point and can be sintered at a low temperature, deterioration of the inorganic phosphor powder during firing can be suppressed. As a result, it becomes possible to obtain a wavelength conversion member having excellent emission intensity.

Fifth, in the phosphor-containing composition of the present invention, SnO—P ₂ O ₅ glass is mol% as a composition, SnO 35-80%, P ₂ O ₅ 5-40%, B ₂ O ₃ 0 It is characterized by containing ~ 30%.

  Sixth, in the phosphor-containing composition of the present invention, the inorganic phosphor powder comprises oxide, nitride, oxynitride, sulfide, oxysulfide, rare earth sulfide, aluminate chloride, and halophosphate chloride. It is at least one selected from the above.

  Seventh, the phosphor-containing composition of the present invention is characterized in that the content of the inorganic phosphor powder in the inorganic powder is 0.01 to 30% by mass.

  Eighth, the phosphor-containing composition of the present invention is granular.

  When the phosphor-containing composition is granular, it is easy to handle compared to a fine powder before granulation. Specifically, since the shape of the phosphor-containing composition particles can be made substantially spherical and the particle size can be made uniform, the fluidity of the phosphor-containing composition is improved, and a mold for preforming The reproducibility of the filling amount is good. As a result, it is possible to obtain a wavelength conversion member that is excellent in dimensional accuracy and has little variation in light emission characteristics.

  Ninth, the present invention relates to a wavelength conversion member obtained by firing any of the phosphor-containing compositions.

  10thly, this invention relates to the LED device characterized by using the said wavelength conversion member.

  Eleventhly, the present invention is a method for producing any one of the above phosphor-containing compositions, comprising an inorganic powder containing glass powder and an inorganic phosphor powder, and a polyalkylene carbonate resin dissolved in a solvent. The present invention relates to a method for producing a phosphor-containing composition, wherein the solvent is removed after mixing.

  12thly, the manufacturing method of the fluorescent substance containing composition of this invention is characterized by performing a solvent removal with a granulator.

  According to this configuration, it is possible to easily produce a substantially spherical granular phosphor-containing composition having a desired particle size.

  Thirteenthly, the present invention relates to a process for obtaining a preform by molding any one of the phosphor-containing compositions into a predetermined shape, a process for heat degreasing the preform, and a preform after degreasing. And a step of baking the glass powder at a temperature equal to or higher than the softening point of the glass powder.

  14thly, the manufacturing method of the wavelength conversion member of this invention is characterized by performing baking of the preform after degreasing | defatting in inert atmosphere.

Depending on the type of glass powder to be used, when baked in an oxidizing atmosphere such as the air, the luminescence intensity of the wavelength conversion member may be significantly reduced due to blackening (for example, SnO—P ₂ O ₅ glass). . Even when such glass powder is used, it is possible to produce a wavelength conversion member that suppresses blackening and has excellent emission intensity by firing the preform in an inert atmosphere. Become.

  In addition, by performing the firing of the preform in an inert atmosphere, it is possible to suppress the deterioration of the inorganic phosphor powder during firing.

  Fifteenth, the wavelength conversion member manufacturing method of the present invention is characterized in that the inert atmosphere is vacuum, nitrogen, or argon.

It is a graph which shows the emission spectrum measured about the wavelength conversion member of an Example.

  The phosphor-containing composition of the present invention is characterized by containing an inorganic powder containing a glass powder and an inorganic phosphor powder, and a polyalkylene carbonate resin.

The glass powder is preferably a low melting point glass that can be sintered at a low temperature. Examples of such glass include SnO—P ₂ O ₅ glass, RO—B ₂ O ₃ —SiO ₂ glass (R = Mg, Ca, Sr, Ba), ZnO—B ₂ O ₃ —SiO ₂ glass. Etc.

The _SnO-P 2 _{O 5} based glass, in mol% as _{composition, SnO 35~80%, P 2 O} 5 5~40%, it is preferable that contain 2 O 3 0~30% _B. The reason why the glass composition is limited to this range will be described below.

  SnO is a component that forms a glass skeleton and lowers the softening point. The SnO content is preferably 35 to 80%, 40 to 70%, 50 to 70%, particularly 55 to 65%. If the SnO content is less than 35%, the softening point of the glass tends to increase, and low-temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member. On the other hand, when the content of SnO is more than 80%, devitrification bumps resulting from Sn are precipitated in the glass, and the transmittance of the glass tends to be lowered. As a result, the wavelength conversion member having high emission intensity is obtained. It becomes difficult to obtain. Moreover, it becomes difficult to vitrify.

P ₂ O ₅ is a component that forms a glass skeleton. The content of P ₂ O ₅ is preferably 5 to 40%, 10 to 30%, particularly preferably 15 to 24%. When the content of P ₂ O ₅ is less than 5%, vitrification becomes difficult. On the other hand, when the content of P ₂ O ₅ is more than 40%, the softening point of the glass tends to increase, and low-temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member. Further, the weather resistance tends to be remarkably lowered.

In order to lower and stabilize the softening point of the glass, the value of SnO / P ₂ O ₅ is 0.9 to 16, 1.5 to 16, 1.5 to 10, particularly in molar ratio. It is preferable that it is 2-5. When the value of SnO / P ₂ O ₅ is smaller than 0.9, the softening point of the glass tends to increase, and low-temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member. Moreover, it exists in the tendency for the weather resistance of glass to fall remarkably. On the other hand, when the value of SnO / P ₂ O ₅ is larger than 16, devitrification bumps due to Sn are precipitated in the glass, and the transmittance of the glass tends to be lowered. As a result, the wavelength having high luminous efficiency. It becomes difficult to obtain the conversion member.

B ₂ O ₃ is a component that suppresses the reaction between the glass and the inorganic phosphor powder and improves the weather resistance. It is also a component that stabilizes the glass. The content of B ₂ O ₃ is preferably 0 to 30%, 1 to 30%, 2 to 20%, particularly 4 to 18%. When the content of B ₂ O ₃ is more than 30%, it reacts with the inorganic phosphor powder and the weather resistance tends to decrease. In addition, the softening point of the glass tends to increase, and low temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member.

  In addition to the above components, the following components can be added.

Al ₂ O ₃ is a component that stabilizes the glass. The content of Al ₂ O ₃ is preferably 0 to 10%, 0 to 7%, particularly preferably 1 to 5%. When the content of Al ₂ O ₃ is more than 10%, the softening point of the glass tends to increase and low temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member.

SiO ₂ is a component that stabilizes the glass in the same manner as Al ₂ O ₃ . The content of SiO ₂ is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. When the content of SiO ₂ exceeds 10%, the softening point of the glass tends to increase, and low-temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member. Moreover, it becomes easy to phase-separate glass.

Li ₂ O is a component that greatly reduces the softening point of the glass and has a large effect of improving the emission intensity of the inorganic phosphor powder. The content of Li ₂ O is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. When the content of Li ₂ O is more than 10%, the glass becomes extremely unstable and becomes difficult to vitrify.

Na ₂ O is a component that has the effect of lowering the softening point of the glass and improving the emission intensity of the inorganic phosphor powder. The content of Na ₂ O is preferably 0 to 10%, 0 to 7%, or 1 to 5%. When the content of Na ₂ O is more than 10%, the glass becomes unstable and becomes difficult to vitrify.

K ₂ O is a component having an effect of lowering the softening point of the glass and improving the emission intensity of the inorganic phosphor powder. The content of K ₂ O is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. If the content of K ₂ O is more than 10%, the glass becomes unstable and is difficult to vitrify.

_{Incidentally,} 0% Li 2 O, Na ₂ O and _{K 2} O in total 0 to 7%, and particularly preferably 1 to 5%. If the total amount of these components exceeds 10%, the glass becomes unstable and it is difficult to vitrify.

  MgO is a component that has a great effect of stabilizing the glass to facilitate vitrification and improving the emission intensity of the inorganic phosphor powder. The content of MgO is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. When the content of MgO is more than 10%, the glass tends to be devitrified and the transmittance tends to decrease, and as a result, it becomes difficult to obtain a wavelength conversion member having high emission intensity.

  CaO is a component that stabilizes glass and facilitates vitrification. The content of CaO is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. If the content of CaO is more than 10%, the glass tends to be devitrified, and the transmittance of the glass tends to decrease. As a result, it becomes difficult to obtain a wavelength conversion member having high emission intensity.

  SrO is a component that stabilizes glass and facilitates vitrification. The content of SrO is preferably 0 to 10%, 0 to 7%, particularly 1 to 5%. If the SrO content is more than 10%, the glass tends to be devitrified, and the transmittance tends to decrease. As a result, it becomes difficult to obtain a wavelength conversion member having high emission intensity.

  BaO is a component that stabilizes glass and facilitates vitrification. The BaO content is preferably 0 to 5%, 0 to 3%, and 0.1 to 1%. If the content of BaO is more than 5%, the glass tends to devitrify significantly and the transmittance tends to decrease. As a result, it becomes difficult to obtain a wavelength conversion member having high emission intensity.

  In addition, it is preferable that MgO, CaO, SrO and BaO are 0 to 10%, 0 to 7%, particularly 1 to 5% in total. When the total amount of these components exceeds 10%, the glass tends to be devitrified, and the transmittance tends to decrease. As a result, it becomes difficult to obtain a wavelength conversion member having high emission intensity.

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, in order to improve the weather resistance, ZnO, Ta ₂ O ₅ , TiO ₂ , Nb ₂ O ₅ , Gd ₂ O ₃ , La ₂ O ₃ may be added up to 10% in total.

However, when colored components such as Fe ₂ O ₃ , Cr ₂ O ₃ , CoO, CuO, NiO are added, the glass is colored and the internal transmittance is lowered. Therefore, these components are combined in an amount of 0.02% or less. It is preferable to limit.

  The average particle diameter D50 of the glass powder is preferably 0.1 to 10 μm, 1 to 10 μm, particularly 1 to 4 μm. When the average particle diameter D50 of the glass powder is less than 0.1 μm, it tends to be charged with static electricity and tends to be difficult to handle. On the other hand, when the average particle diameter D50 exceeds 10 μm, in the wavelength conversion member obtained by firing, the leakage due to the glass particles tends to occur, and the chromaticity variation tends to increase.

  The glass powder may be adjusted to a desired average particle size by using a known pulverizing apparatus such as a ball mill, a rake machine, a jet mill, or a bead mill.

  The softening point of the glass powder is preferably 500 ° C. or lower, 450 ° C. or lower, and particularly preferably 400 ° C. or lower. If the softening point exceeds 500 ° C., low-temperature sintering becomes difficult. As a result, the inorganic phosphor powder easily deteriorates during firing, which causes a decrease in the emission intensity of the wavelength conversion member.

  Examples of the inorganic phosphor powder used in the present invention include those that emit fluorescence having a wavelength longer than the wavelength of the excitation light when ultraviolet or visible excitation light is incident. For example, when an inorganic phosphor powder that emits complementary fluorescence to the hue of the excitation light when incident excitation light composed of visible light is incident, white light is easily obtained by synthesizing the transmitted excitation light and fluorescence. A white LED device can be manufactured. For example, when the excitation light composed of visible light is light having a central wavelength of 430 to 490 nm and fluorescence is light having a central wavelength of 530 to 590 nm, white light can be easily obtained.

  Specific examples of the inorganic phosphor powder that can be used in the present invention are not particularly limited as long as they are generally available on the market. Examples thereof include garnets such as YAG and other oxides, nitrides, oxynitrides, sulfides, oxysulfides, rare earth sulfides, aluminate chlorides, halophosphates, and the like.

  Among the inorganic phosphor powders, those having an excitation band at a wavelength of 300 to 500 nm and an emission peak at a wavelength of 380 to 780 nm, particularly blue (wavelength 440 to 480 nm), green (wavelength 500 to 540 nm), yellow (wavelength 540) ˜595 nm) and red (wavelength of 600 to 700 nm) are preferably used.

Examples of inorganic phosphor powder that emits blue light when irradiated with ultraviolet to near-ultraviolet excitation light having 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+ and the} like.

As inorganic phosphor powders that emit green fluorescence when irradiated with ultraviolet to near-ultraviolet excitation light having a wavelength of 300 to 440 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⁺ , 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 0.2 Ba 0.7 Cl 1.1 Al 2 O 3.45: Ce 3+ ^{_{Mn 2+, Ba 2 MgSi 2 O}} 7: Eu 2+, Ba 2 SiO 4: Eu 2+, Ba 2 Li 2 Si 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+ and the} like.

Examples of inorganic phosphor powders that emit green fluorescence when irradiated with blue excitation light having a wavelength of 440 to 480 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+ and the} like.

Examples of inorganic phosphor powder that emits yellow fluorescence when irradiated with ultraviolet to near-ultraviolet excitation light having 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+ and the} like can be mentioned.

As an inorganic phosphor powder that emits 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⁺ , Sr ₂ SiO ₄ : Eu ²⁺ .

Examples of the inorganic phosphor powder that emits red fluorescence when irradiated with ultraviolet to near-ultraviolet excitation light having 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+ and the} like.

Examples of inorganic phosphor powders 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⁺ , CaS: 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 and the} like.

  A plurality of inorganic phosphor powders may be mixed and used in accordance with the wavelength range of excitation light or light emission. For example, when white light is obtained by irradiation with ultraviolet excitation light, inorganic phosphor powders emitting blue, green, yellow, and red fluorescence may be mixed and used.

  When the content of the inorganic phosphor powder in the inorganic powder is too large, it becomes difficult to sinter, resulting in problems such as increased porosity and increased light scattering loss. On the other hand, when there is too little content of inorganic fluorescent substance powder, it becomes difficult to obtain sufficient light emission. Therefore, the content of the inorganic phosphor powder in the inorganic powder is preferably 0.01 to 30% by mass, 0.05 to 20% by mass, and particularly 0.08 to 15% by mass.

  In the phosphor-containing composition of the present invention, a polyalkylene carbonate resin is used as the organic resin. The polyalkylene carbonate-based resin is a polymer having an alkylene carbonate structure composed of an alkylene group and a carbonate group. Examples of the polyalkylene carbonate resin include polyethylene carbonate resin, polypropylene carbonate resin, polybutene carbonate resin, polypentene carbonate resin, polyhexene carbonate resin, and the like. Among these, it is preferable to use a polyethylene carbonate resin and a polypropylene carbonate resin because they are relatively easily decomposed by heat treatment.

  The weight average molecular weight of the polyalkylene carbonate-based resin is not particularly limited, and, for example, those in the range of 10,000 to 1,000,000, further 200,000 to 500,000 can be used.

  In the phosphor-containing composition of the present invention, the content of the polyalkylene carbonate-based resin is 0.1 to 20 parts by mass, 0.5 to 15 parts by mass, 1 to 10 parts by mass with respect to 100 parts by mass of the inorganic powder. In particular, it is preferably 1 to 5 parts by mass. If the content of the polyalkylene carbonate resin is less than 0.1 parts by mass, it tends to be difficult to produce granules. On the other hand, when the content of the polyalkylene carbonate-based resin exceeds 20 parts by mass, the carbon component tends to remain after firing, which tends to cause a decrease in emission intensity of the wavelength conversion member.

  The phosphor-containing composition of the present invention is preferably granular. The average particle diameter D50 of the granules is preferably 10 to 300 μm, particularly 40 to 100 μm. When the average particle diameter D50 of the granules is less than 10 μm, the fluidity is inferior and the filling amount in the mold tends to vary. On the other hand, when the average particle diameter D50 of the granules exceeds 300 μm, the gap between the particles becomes large when filling the mold, and the filling amount is likely to vary. Therefore, in any case, the dimensional accuracy of the wavelength conversion member obtained after firing is inferior, and the emission intensity tends to vary.

  The phosphor-containing composition of the present invention can be prepared by mixing an inorganic powder containing a glass powder and an inorganic phosphor powder and a polyalkylene carbonate resin dissolved in a solvent and then removing the solvent. .

  Examples of the solvent include known organic solvents such as acetone and dimethyl carbonate.

  The mixing method of the inorganic powder and the polyalkylene carbonate resin dissolved in the solvent is not particularly limited, and both may be kneaded in a container, and the inorganic powder is sprayed with the polyalkylene carbonate resin dissolved in the solvent. May be.

  The method for removing the solvent is not particularly limited, but it is preferably performed by a granulator. This makes it possible to easily produce a substantially spherical granular phosphor-containing composition having a desired particle size. It does not specifically limit as a granulator, A spray dryer other than a general stirring type granulator may be sufficient. In addition, it is preferable to select the granulator to be used according to the average particle diameter of the target fluorescent substance-containing composition. For example, when preparing a phosphor-containing composition having an average particle diameter D50 of 150 μm or less, it is preferable to use a spray dryer, and when preparing a phosphor-containing composition having an average particle diameter larger than 150 μm, stirring granulation It is preferable to use a machine.

  The wavelength conversion member of the present invention comprises a step of forming the phosphor-containing composition into a predetermined shape to obtain a preform, a step of heat-treating the preform and degreasing, and a preform after degreasing of the glass powder. It can be manufactured through a step of baking at a temperature equal to or higher than the softening point.

  The preform can be produced, for example, by filling a phosphor-containing composition in a mold and press molding.

  The heat treatment of the preform is not particularly limited as long as the polyalkylene carbonate-based resin is sufficiently decomposed (degreased), and is preferably performed at, for example, 200 to 400 ° C, particularly 250 to 350 ° C.

  The calcining temperature of the preform after degreasing is performed at or above the softening point of the glass powder. The upper limit is not particularly limited, but if the firing temperature is too high, the inorganic phosphor powder reacts with the glass powder and tends to deteriorate, so the softening point is + 100 ° C. or less, especially the softening point + 50 ° C. or less. Is preferred.

The firing atmosphere of the preform after degreasing is preferably an inert atmosphere. In particular, SnO—P ₂ O ₅ glass has a problem that when it is sintered in the air, the Sn component is oxidized and does not sinter sufficiently. Moreover, if it is an inert atmosphere baking, it will become possible to suppress degradation of the inorganic fluorescent substance powder at the time of baking.

Examples of the inert atmosphere include vacuum, nitrogen, argon, and the like. Although the vacuum degree of a vacuum atmosphere is not specifically limited, For example, it is preferable to adjust to the range of 10 ^<-5 > ^-10 < ⁴ > Pa.

  The wavelength conversion member of the present invention can be used as a white LED or a colored LED other than white by combining with a blue, ultraviolet, or near ultraviolet LED chip. The shape of the wavelength conversion member can be spherical, hemispherical, meniscus lens, box, conical, or thin plate as required.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to this Example.

Example 1
(1) Production of phosphor-containing composition First, glass raw materials were weighed so as to have a composition of mol%, SnO 59% P ₂ O ₅ 26% B ₂ O ₃ 13% Al ₂ O ₃ 2%. The glass raw material was put into an alumina crucible and melted in an electric furnace at 950 ° C. in a nitrogen atmosphere for 2 hours. Thereafter, the glass melt was poured between a pair of cooling rolls to form a film, and the film glass was then pulverized using a jet mill to obtain glass powder (average particle diameter D50 = 3 μm, softening point 400 ° C.). .

As the inorganic phosphor powder, a silicate phosphor emitting yellow light (manufactured by Intematix, R ₂ SiO ₄ : Eu ²⁺ , R = alkaline earth metal) is prepared, and glass powder: inorganic phosphor powder = 95: 5 ( (Mass ratio).

  A polypropylene carbonate resin corresponding to 10 parts by mass was dissolved in a predetermined amount of acetone with respect to 100 parts by mass of a mixture of glass powder and inorganic phosphor powder. Thereafter, glass powder, inorganic phosphor powder, and polypropylene carbonate resin solution were mixed with a stirrer to obtain a uniform slurry.

  The obtained slurry was sprayed and dried using a spray dryer to obtain a granular phosphor-containing composition.

(2) Production of Wavelength Conversion Member A granular phosphor-containing composition was press-molded into a plate shape (10 × 10 × 0.5 mm) using a press to produce a preform. The preform was put into an atmosphere substitution furnace, degreased in vacuum (10 ³ Pa) at 300 ° C. for 1 hour, heated to 400 ° C., held for 30 minutes and fired to prepare a wavelength conversion member. .

(3) Measurement of total luminous flux value A wavelength conversion member was installed on a blue LED having a wavelength of 460 nm, and the blue LED was turned on at a current of 600 mA in a calibrated integrating sphere. The obtained light was taken into a small spectroscope (USB-4000 manufactured by Ocean Optics) through an optical fiber, and an emission spectrum (energy distribution curve) was obtained on the control PC (FIG. 1). The total luminous flux value (lm) was calculated from the emission spectrum using control software (OP Wave manufactured by Ocean Photonics). The results are shown in Table 1.

(Example 2)
The resin solution was the same as in Example 1 except that a resin solution in which a polyethylene carbonate resin corresponding to 10 parts by mass was dissolved in a predetermined amount of dimethyl carbonate with respect to 100 parts by mass of a mixture of glass powder and inorganic phosphor powder was used. A granular phosphor-containing composition was obtained by this method.

  Furthermore, using the obtained phosphor-containing composition, preforming and firing were performed in the same manner as in Example 1 to prepare a wavelength conversion member. With respect to the obtained wavelength conversion member, the total luminous flux value was measured by the same method as in Example 1. The obtained spectrum was almost the same as in FIG.

(Comparative example)
A phosphor-containing composition and a wavelength conversion member were produced in the same manner as in the examples except that an acrylic resin (trade name: Elbasite 2044) was used instead of polypropylene carbonate.

  With respect to the obtained wavelength conversion member, the total luminous flux value was measured by the same method as in Example 1. The results are shown in Table 1.

  In Examples 1 and 2, a wavelength conversion member having a transparent appearance was obtained, and white light was obtained. On the other hand, the wavelength conversion member of the comparative example was opaque in appearance and did not emit light at all.

Claims (15)

  A phosphor-containing composition comprising: an inorganic powder containing glass powder and an inorganic phosphor powder; and a polyalkylene carbonate resin.   The phosphor-containing composition according to claim 1, wherein the polyalkylene carbonate resin is a polyethylene carbonate resin or a polypropylene carbonate resin.   The phosphor-containing composition according to claim 1 or 2, comprising 0.1 to 20 parts by mass of a polyalkylene carbonate-based resin with respect to 100 parts by mass of the inorganic powder. The phosphor-containing composition according to claim 1, wherein the glass powder is SnO—P ₂ O ₅ glass. _SnO-P 2 _{O 5} based glass, in mol% as the composition, according to claim 4, characterized in that it contains _{SnO 35~80%, P 2 O 5} 5~40%, the 2 O 3 0 to 30% _B 2. The phosphor-containing composition according to 1.   The inorganic phosphor powder is at least one selected from oxide, nitride, oxynitride, sulfide, oxysulfide, rare earth sulfide, aluminate chloride, and halophosphate chloride The phosphor-containing composition according to any one of claims 1 to 5.   Content of the inorganic fluorescent substance powder in inorganic powder is 0.01-30 mass%, The fluorescent substance containing composition in any one of Claims 1-6 characterized by the above-mentioned.   The phosphor-containing composition according to claim 1, wherein the phosphor-containing composition is granular.   A wavelength conversion member obtained by firing the phosphor-containing composition according to claim 1.   An LED device using the wavelength conversion member according to claim 9.   A method for producing the phosphor-containing composition according to any one of claims 1 to 8, comprising: an inorganic powder containing glass powder and an inorganic phosphor powder; and a polyalkylene carbonate-based resin dissolved in a solvent. A process for producing a phosphor-containing composition, wherein the solvent is removed after mixing.   The method for producing a phosphor-containing composition according to claim 11, wherein the solvent removal is performed by a granulator.   A step of forming the phosphor-containing composition according to any one of claims 1 to 8 into a predetermined shape to obtain a preform, a step of heat-treating the preform and degreasing, and a preform after degreasing the glass And a step of firing at a temperature equal to or higher than the softening point of the powder.   The method for producing a wavelength conversion member according to claim 13, wherein the preform after degreasing is fired in an inert atmosphere.   The method for producing a wavelength conversion member according to claim 14, wherein the inert atmosphere is vacuum, nitrogen, or argon.