Molded body, light-emitting device, and method for manufacturing the molded body

Abstract

To provide a molding having excellent color rendering and heat resisting properties, a light emitting device and a method for producing the molding.SOLUTION: A molding 31 has: a translucent substrate 101 composed of an inorganic material containing first phosphor particles 101a; second phosphor particles 102a disposed on the substrate 101; and translucent second ceramic 102b for fixing the second phosphor particles 102a to the substrate 101. A surface of the molding 31 is provided with irregularities resulting from the second phosphor particles 102a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a molded article, a light emitting device, and a method for manufacturing the molded article. [Background technology]

[0002] Light-emitting devices that combine light-emitting elements such as light-emitting diodes (LEDs) and semiconductor laser (LD) chips with phosphors are used as illumination, backlights for liquid crystal displays, vehicle lights, light sources for projectors, etc. Light-emitting devices are required to be compact depending on the purpose and location of application. In addition, for example, in a projector light source that uses an LD as a light-emitting element, high-energy light is locally emitted from the light-emitting element, so a member containing a phosphor that converts the wavelength of the light emitted from the light-emitting element is required to have high heat resistance.

[0003] For example, Patent Document 1 discloses a wavelength conversion member that is made of an inorganic material such as glass or sapphire with good thermal conductivity and that has a phosphor layer made of a phosphor and a translucent ceramic on a light-transmitting base material. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2017 / 126440 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of one aspect of the present invention is to provide a molded article, a light-emitting device, and a method for manufacturing the molded article, which are excellent in color rendering properties and heat resistance. [Means for solving the problem]

[0006] The present invention includes the following aspects. A first aspect of the present invention is a molded body including a light-transmitting base made of an inorganic material containing first phosphor particles, second phosphor particles arranged on the base, and a light-transmitting second ceramic that fixes the second phosphor particles to the base, wherein unevenness caused by the second phosphor particles is formed on the surface of the molded body.

[0007] A second aspect of the present invention is a light emitting device including the molded body and an excitation light source.

[0008] A third aspect of the present invention is a method for producing a molded body, comprising: preparing a light-transmitting base made of an inorganic material containing first phosphor particles; preparing a phosphor-containing composition containing second phosphor particles and a second inorganic binder; applying the phosphor-containing composition to the base; and subjecting the base and the phosphor-containing composition to a first heat treatment to fix the second phosphor particles to a surface of the base via a light-transmitting second ceramic derived from the second inorganic binder, thereby obtaining a molded body having unevenness on its surface caused by the second phosphor particles. Effect of the Invention

[0009] According to one aspect of the present invention, it is possible to provide a molded article, a light emitting device, and a method for manufacturing a molded article, which are excellent in color rendering properties and heat resistance. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a schematic cross-sectional view showing a molded body according to the first embodiment. [Diagram 2] FIG. 4 is a schematic cross-sectional view showing a molded body according to a second embodiment. [Diagram 3] FIG. 11 is a schematic cross-sectional view showing a molded body according to a third embodiment. [Figure 4] FIG. 11 is a schematic cross-sectional view showing a molded body according to a fourth embodiment. [Diagram 5] FIG. 11 is a schematic cross-sectional view showing a molded body according to a fifth embodiment. [Figure 6A] FIG. 1 is a schematic perspective view showing a light-emitting module, which is an example of a light-emitting device. [Figure 6B] 1 is a schematic plan view showing a light-emitting module which is an example of a light-emitting device. [Figure 6C] FIG. 6C is a cross-sectional view taken along line VIC-VIC in FIG. 6B. [Figure 6D] FIG. 6C is a cross-sectional view taken along line VID-VID in FIG. 6B. [Figure 6E] FIG. 1 is a schematic cross-sectional view showing a light-emitting device including a molded body as a light-transmitting member. [Figure 6F] FIG. 2 is a schematic bottom view of the light emitting device. [Figure 7] 1 is a flowchart illustrating an example of a manufacturing method. [Figure 8] 1 is a flowchart illustrating an example of a manufacturing method. [Figure 9] FIG. 1 is a schematic side view showing an overview of a light source device for a projector. [Figure 10A] 10 is a schematic plan view showing one surface of the phosphor wheel as viewed from the arrow A in FIG. 9. [Figure 10B] 10 is a schematic plan view showing one surface of the phosphor wheel as viewed from the arrow B in FIG. [Figure 10C] 10 is a schematic plan view showing one surface of the phosphor wheel as viewed from the arrow C in FIG. 9. [Figure 11] FIG. 1 is a schematic diagram illustrating a configuration of a projector equipped with a light source device. [Figure 12] 13 is a plan SEM photograph of a base on a side where second phosphor particles exist before a third ceramic and a fourth ceramic are formed in Example 11. [Figure 13] FIG. 23 is a diagram illustrating a binarized state of a planar SEM photograph of the base on the side where the second phosphor particles are present before the third ceramic and the fourth ceramic are formed in Example 11. [Figure 14] 13 is a SEM photograph of a partial cross section of a molded body before the third ceramic and the fourth ceramic are formed in Example 11. [Figure 15] FIG. 13 is an SEM-EDS element mapping diagram of a partial cross-sectional SEM photograph of a molded body before the formation of the third ceramic and the fourth ceramic in Example 11. [Figure 16] FIG. 13 is an SEM-EDS element mapping diagram illustrating locations where Si exists in an SEM photograph of a partial cross section of a molded body before the formation of the third ceramic and the fourth ceramic in Example 11. [Figure 17] FIG. 13 is an SEM-EDS element mapping diagram showing locations where Sr exists in an SEM photograph of a partial cross section of a molded body before the formation of the third ceramic and the fourth ceramic in Example 11. [Figure 18] FIG. 13 is a SEM-EDS element mapping diagram showing locations where Ca exists in a SEM photograph of a partial cross section of a compact before the formation of the third ceramic and the fourth ceramic in Example 11. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The molded body, light-emitting device, and method for manufacturing the molded body according to the present invention will be described below based on one embodiment. However, the embodiment shown below is an example for embodying the technical idea of ​​the present invention, and the present invention is not limited to the molded body, light-emitting device, and method for manufacturing the molded body described below. The relationship between the color name and the chromaticity coordinates is in accordance with JIS Z8110. The above-mentioned Patent Document 1 describes the use of glass or sapphire, which has high thermal conductivity, as the substrate, but does not describe the use of phosphor particles as the substrate. The phosphor layer is formed on the substrate. It is described that if the thickness of the phosphor layer is excessively thin compared to the particle diameter of the phosphor particles, the excitation light passes through without being wavelength-converted by the phosphor, and the performance of converting the wavelength of the excitation light is not fully exhibited. It is also disclosed that depending on the size of the particle diameter of the phosphor, a thickness of the phosphor layer of 1.5 or more is required for the particle diameter of the phosphor, and depending on the particle diameter of the phosphor, the demand for thinning may not be met. Furthermore, it is described that by using a substrate with high thermal conductivity, heat accumulation of the phosphor layer is suppressed, and when the thickness of the phosphor layer exceeds a certain number times the particle diameter of the phosphor, the thermal resistance of the grain boundary increases, the temperature of the phosphor layer increases, and the luminous intensity decreases. Depending on the particle diameter of the phosphor particles, it may not be possible to contain the desired phosphor in the phosphor layer, and the desired luminous color may not be obtained. In contrast, the molded body and light-emitting device according to the present embodiment can provide a body with excellent color rendering and heat resistance. In other words, by using first phosphor particles having a predetermined thickness on the base and arranging second phosphor particles so as to compensate for the poor color rendering, it is possible to improve the color rendering as a whole. In addition, in a base using only the first phosphor particles, or the first phosphor particles as the main material and the first ceramic or glass as the secondary material, the heat generated in the first phosphor particles is transferred to the adjacent first phosphor particles, and the heat can be efficiently released to the outside, so that a molded body with excellent heat resistance can be provided. In addition, the heat generated in the second phosphor particles is also transferred to the first phosphor particles, and the heat can be efficiently released to the outside, so that a molded body with excellent heat resistance can be provided. The second phosphor particles are excellent in heat resistance because only the second ceramic is used to the extent that unevenness can be created. A base using the first phosphor particles as the main material and the first ceramic or glass as the secondary material refers to a base in which the content of the first phosphor particles in the base is greater than the content of the first ceramic or glass.

[0012] Molded body The molded body includes a light-transmitting base made of an inorganic material containing first phosphor particles, second phosphor particles arranged on the base, and a light-transmitting second ceramic that fixes the second phosphor particles to the base. The surface of the molded body has unevenness caused by the second phosphor particles. The base may further include at least one of a first ceramic and glass in addition to the first phosphor particles. In this specification, ceramic means an inorganic non-metallic material at a temperature of 1000°C or less. The molded body includes a base made of an inorganic material containing the first phosphor particles and the first ceramic, and the second phosphor particles fixed by the second ceramic, and is made of an inorganic material, so it has excellent heat resistance. In addition, even when the molded body includes a third phosphor particle, a third ceramic, and a fourth ceramic described later, it has excellent heat resistance because it is made of an inorganic material. In this specification, "the surface of the molded body has unevenness caused by the second phosphor particles" refers to the state before multiple layers, such as a third ceramic and a fourth ceramic, are arranged, i.e., the surface of the molded body formed by the base, the second phosphor particles, and the second ceramic.

[0013] FIG. 1 is a schematic cross-sectional view showing a molded body according to the first embodiment. The molded body 31 includes a light-transmitting base 101 made of an inorganic material containing a first phosphor particle 101a and a first ceramic 101b, a second phosphor particle 102a arranged on the base 101, and a light-transmitting second ceramic 102b that fixes the second phosphor particle 102a to the base 101. The surface of the molded body 31 has unevenness caused by the second phosphor particle 102a. The second phosphor particle 102a is present intermittently in the horizontal direction on the surface of the base 101. The second ceramic 102b is a ceramic derived from a second inorganic binder, and fixes the second phosphor particle 102a to the base 101. The reason why the surface of the molded body 31 has unevenness due to the second phosphor particles 102a is, for example, when there are parts where the second phosphor particles 102a with a large particle size are present and parts where the second phosphor particles 102a with a small particle size are present in the horizontal direction along the surface of the base 101, when the height of the second phosphor particles 102a differs due to differences in particle size or how the particles are piled up, or when there are parts where the second phosphor particles 102a are present and parts where the second phosphor particles 102a are not present. The part where the second phosphor particles 102a are not present means that there is a part on the surface of the base 101 where the second phosphor particles 102a are not present. In this specification, even if there is a part where the second phosphor particles 102a are not present in the horizontal direction along the surface of the base 101, there is no void and it is covered with the second ceramics 102b. In addition, the materials such as the first ceramics and the second ceramics using the inorganic binder may be the same or different unless otherwise specified.

[0014] In the horizontal direction along the surface of the base 101, the second phosphor particles 102a and the second ceramics 102b, which are present intermittently, do not form a layer of uniform thickness. The surface of the base 101 has a portion E where the second phosphor particles 102a are present intermittently and a portion N where the second phosphor particles 102a are not present. In the portion N where the second phosphor particles 102a are not present on the surface of the base 101, only the second ceramics 102b may be present, or the second ceramics 102b may not be present. The portion where the second phosphor particles 102a are present is convex, and the portion where the second phosphor particles 102a are not present, that is, the portion where only the second ceramics 102b is present, is concave compared to the portion where the second phosphor particles 102a are present. As a result, unevenness caused by the second phosphor particles 102a is formed on the surface of the molded body 31. The surface of the molded body 31 has irregularities caused by the second phosphor particles 102a, and the surface roughness Ra of the irregularities is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less, and particularly preferably 6.6 μm or less. The surface roughness Ra of the irregularities is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and particularly preferably 5 μm or more. However, this surface roughness Ra varies depending on the size of the second phosphor particles 102a, so it is not limited to this.

[0015] From the molded body 31, light that has been wavelength-converted by the second phosphor particles 102a fixed to the surface of the base 101 so as to have unevenness, and light from the excitation light source that has passed through the translucent base 101 from the portion where the second phosphor particles 102a are not present, and light that has been wavelength-converted by the first phosphor particles 101a contained in the base 101 are emitted, and mixed color light with excellent color rendering properties can be emitted by the light from the excitation light source, the light that has been wavelength-converted by the first phosphor particles 101a, and the light that has been wavelength-converted by the second phosphor particles 102a. In addition, the molded body 31 can reduce color unevenness by diffuse reflection of the emitted light due to the unevenness on its surface caused by the second phosphor particles 102a. In addition, since the second phosphor particles 102a, which are present in the molded body 31 so as to form unevenness on its surface, are fixed by the second ceramics 102b, the film thickness of the second phosphor particles 102a and the second ceramics 102b can be made thinner than a layer formed by piling up the second phosphor particles 102a, and the requirement for a thinner body can be satisfied. This is because the thickness of the molded body 31 can be made thinner by reducing the amount of the second ceramics 102b.

[0016] In a plan view of the molded body 31, when the unit area of ​​the surface of the base 101 is taken as 100%, the total surface area where the second phosphor particles 102a are present is preferably 97% or less, more preferably 90% or less, even more preferably 80% or less, even more preferably 78% or less, and particularly preferably 72% or less. In addition, when the unit area of ​​the surface of the base 101 is taken as 100%, the total surface area where the second phosphor particles 102a are present is preferably 10% or more, more preferably 20% or more, even more preferably 25% or more, even more preferably 30% or more, and particularly preferably 35% or more. In a plan view of the molded body 31, the total surface area where the second phosphor particles 102a are present relative to 100% of the unit area of ​​the surface of the base 101 is also called the coverage rate. In a plan view, if the total surface area of ​​the second phosphor particles 102a present on the surface of the base 101 is 97% or less relative to 100% of the unit area of ​​the surface of the base 101, then it is possible to extract light whose wavelength has been converted by the first phosphor particles 101a in the base 101 from areas where the second phosphor particles 102a are not present, and light from an excitation light source that has passed through the translucent base 101 without being wavelength converted by the first phosphor particles 101a. This light and the light whose wavelength has been converted by the second phosphor particles 102a can produce mixed-color light having the desired chromaticity from the molded body 31, thereby satisfying the requirement for thinness. When the unit area of ​​the surface of the base is taken as 100% in a plan view of the molded body, the total surface area (coverage) on which the second phosphor particles are present can be calculated by, for example, using a scanning electron microscope (SEM) to obtain an SEM image of the plane of the molded body on the side on which the second phosphor particles are present, performing image analysis using, for example, the image analysis software used in the examples described below, binarizing the second phosphor particles, setting the area of ​​the SEM image to be measured to 100%, and calculating the total area of ​​the binarized second phosphor particles as the coverage of the second phosphor particles.

[0017] 2 is a schematic cross-sectional view showing a molded body according to the second embodiment. The molded body 32 according to the second embodiment is different from the molded body 31 according to the first embodiment in that the base 101 is made of only the first phosphor particles 101a. The first phosphor particles 101a of a predetermined size are sintered and solidified at a predetermined temperature. Since the base 101 can be formed only from the first phosphor particles 101a, it has excellent heat resistance. The surfaces of at least some of the first phosphor particles 101a may be partially or entirely melted, thereby fixing the first phosphor particles 101a together.

[0018] FIG. 3 is a schematic cross-sectional view showing a molded body according to the third embodiment. The molded body 33 according to the third embodiment is different from the molded body 31 according to the first embodiment in that the phosphor arranged on the surface of the base 101 is a third phosphor particle 102c arranged in addition to the second phosphor particle 102a. This makes it possible to obtain mixed-color light having a desired chromaticity from the molded body. The molded body 33 further includes a third phosphor particle 102c fixed by the second ceramic 102b in the horizontal direction along the surface of the base 101 and emitting light in a wavelength range different from that of the second phosphor particle 102a. The third phosphor particle 102c may be arranged adjacent to the second phosphor particle 102a in the horizontal direction along the surface of the base 101, or may be arranged away from the second phosphor particle 102a. The third phosphor particle 102c may be arranged in a portion of the surface of the base 101 where the second phosphor particle 102a is not arranged. The third phosphor particles 102c may be disposed in the concave portions of the concave portions of the second phosphor particles 102a. This allows the second phosphor particles 102a and the third phosphor particles 102c to correct the color tone and reduce the thickness.

[0019] FIG. 4 is a schematic cross-sectional view showing a molded body according to the fourth embodiment. The molded body 34 according to the fourth embodiment is different from the molded body 31 according to the first embodiment in that a translucent third ceramic 103 is fixed onto the second phosphor particles 102a. This makes it possible to prevent the second phosphor particles 102a from falling off or peeling off. In addition, it is possible to eliminate or reduce unevenness on the surface of the molded body 34. Furthermore, it is also possible to increase the extraction efficiency of light emitted from the molded body 34.

[0020] FIG. 5 is a schematic cross-sectional view showing a molded body according to the fifth embodiment. The molded body 35 according to the fifth embodiment is different from the molded body 34 according to the fourth embodiment in that the fourth ceramic 104 is fixed on the third ceramic 103 on the second phosphor particle 102a. In the molded body 35, the third ceramic 103 is fixed on the second phosphor particle 102a on which the unevenness caused by the second phosphor particle 102a is formed, and the fourth ceramic 104 is fixed on the third ceramic 103. This prevents the second phosphor particle 102a fixed to the base 101 by the second ceramic 102b from falling off or peeling off, and can further increase the adhesion between the second phosphor particle 102a and the base 101. In addition, the unevenness difference on the surface of the fourth ceramic 104 can be reduced or eliminated. Here, the molded body has a surface on which irregularities caused by the second phosphor particles are formed, and is then coated with the third ceramic and the fourth ceramic, so that the irregularities on the surface caused by the second phosphor particles may become smaller, or the irregularities caused by the second phosphor particles may disappear. The components will be described in detail below.

[0021] base body The base is made of an inorganic material containing at least the first phosphor particles. The base may be fixed by sintering or pressing only the first phosphor particles. Since the base can be made of only the first phosphor particles, the wavelength conversion efficiency can be increased. In addition, since the base can be made of only the first phosphor particles, there is no need to consider the deterioration of other members or the difference in linear expansion coefficient with other members. On the other hand, instead of only the first phosphor particles, the base can use an inorganic material containing the first phosphor particles and glass, an inorganic material containing the first phosphor particles and a first ceramic, or an inorganic material containing the first phosphor particles, the first ceramic, and glass. The first phosphor particles alone or any combination is excellent in heat resistance and light resistance because it is made of only inorganic materials. In this specification, the light transmittance means that the light transmittance at the emission peak wavelength of the excitation light is 60% or more, and the light transmittance at the emission peak wavelength of the excitation light is preferably 70% or more, and more preferably 80% or more.

[0022] The base may contain at least one inorganic material selected from a first ceramic and glass that do not convert the wavelength of the excitation light, in addition to the first phosphor particles. The first ceramic is preferably at least one selected from the group consisting of aluminum oxide, aluminum nitride, mullite, and silicon nitride. If the first ceramic is at least one selected from the group consisting of aluminum oxide, aluminum nitride, mullite, and silicon nitride, a base having translucency and excellent heat resistance can be obtained. The first ceramic is more preferably at least one selected from the group consisting of aluminum oxide, aluminum nitride, and silicon nitride. If the first ceramic is at least one selected from the group consisting of aluminum oxide, aluminum nitride, and silicon nitride as the inorganic material contained in the base, a base having translucency, heat resistance, and excellent thermal conductivity can be obtained.

[0023] The glass may be, for example, borosilicate glass. Examples of the borosilicate glass include barium borosilicate glass and aluminoborosilicate glass. The glass may have a softening point of 500° C. or higher, 600° C. or higher, or 700° C. or higher.

[0024] The thickness of the substrate is not particularly limited. In consideration of mechanical strength and wavelength conversion efficiency, the thickness of the substrate is in the range of 1 μm to 1 mm, may be in the range of 10 μm to 800 μm, may be in the range of 50 μm to 500 μm, or may be in the range of 100 μm to 300 μm. The surface roughness Ra of the base is preferably 1.5 μm or less, more preferably 1 μm or less, and particularly preferably 0.9 μm or less, in order to facilitate fixing the second phosphor particles to the base via the second ceramic.

[0025] First phosphor particles The first phosphor particles may be phosphor particles having an emission peak wavelength in the range of 530 nm or more and 590 nm or less when exposed to light from an excitation light source, or may be phosphor particles having an emission peak wavelength in the range of 490 nm or more and 555 nm or less.

[0026] When the first phosphor particles are phosphor particles having an emission peak wavelength in the range of 530 nm or more and 590 nm or less when exposed to light from an excitation light source, the first phosphor particles preferably contain at least one type of aluminate phosphor.

[0027] The aluminate phosphor may be an aluminate phosphor having a composition represented by the following formula (1A). M 1 3(Al,Ga)5O 12 :Ce (1A) In formula (1A), M 1 is at least one selected from the group consisting of Y, Lu, Gd and Tb. In this specification, in a composition formula, a plurality of elements separated by a comma (,) means that at least one of these elements is contained in the composition. A plurality of elements separated by a comma (,) in a composition formula includes at least one element selected from the plurality of elements separated by the comma in the composition, and may include a combination of two or more of the plurality of elements. In this specification, in a formula representing the composition of a phosphor, the part before the colon (:) represents the elements constituting the host crystal and their molar ratio, and the part after the colon (:) represents an activator element.

[0028] In the case where the first phosphor particles are phosphor particles having an emission peak wavelength in the range of 530 nm to 590 nm by light from an excitation light source, the first phosphor particles are preferably YAlO 12 : Ce, Y3(Al,Ga)5O 12 : Ce, (Y, Gd)3Al5O 12 : Ce, Lu3A l5 O 12 : Ce or Lu3(Al,Ga)5O 12 :Ce is one example.

[0029] As described above, or instead of the above, when the first phosphor particles are phosphor particles having an emission peak wavelength in the range of 490 nm to 555 nm by light from an excitation light source, the first phosphor particles may be at least one phosphor selected from the group consisting of an alkaline earth metal silicate phosphor, an alkaline earth metal aluminate phosphor, an alkaline earth metal halosilicate phosphor, and a β-sialon phosphor. For example, the first phosphor particles may be at least one phosphor selected from the group consisting of an alkaline earth metal silicate phosphor having a composition represented by the following formula (1B), an alkaline earth metal aluminate phosphor having a composition represented by the following formula (1C), an alkaline earth metal halosilicate phosphor having a composition represented by the following formula (1D), and a β-sialon phosphor having a composition represented by the following formula (1E).

[0030] BaSi2O2N2:Eu (1B) Sr4Al 14 O 25: Eu (1C) (Ca, Sr, Ba)8MgSi4O 16 (F, Cl, Br)2: Eu (1D) Si 6-a Al a O a N 8-a : Eu (1E) In formula (1E), a is a number satisfying 0 < a < 4.2.

[0031] When the first phosphor particles are phosphor particles having an emission peak wavelength in the range of 490 nm or more and 555 nm or less by the light from the excitation light source, specifically, as the first phosphor particles, Ca8MgSi4O 16 Cl2: Eu etc. may be mentioned.

[0032] The content of the first phosphor particles in the substrate varies depending on the desired chromaticity. As described above, the substrate may be one obtained by sintering the first phosphor particles, and the content of the first phosphor particles in the substrate may be 100%. When the substrate contains at least one inorganic material selected from the first ceramics and glass that do not convert the excitation light in wavelength in addition to the first phosphor particles, the content of the first phosphor particles may be in the range of 0.1% by mass or more and 99.9% by mass or less with respect to the total amount of the inorganic material constituting the substrate and the first phosphor particles. The content of the first phosphor particles is more preferably 0.5% by mass or more, more preferably 1% by mass or more, more preferably 3% by mass or more, and particularly preferably 5% by mass or more. Also, the content of the first phosphor particles is more preferably 95% by mass or less, more preferably 80% by mass or less, more preferably 70% by mass or less, and particularly preferably 50% by mass or less. When the substrate contains at least one inorganic material selected from the first ceramics and glass that do not convert the excitation light in wavelength and the first phosphor particles, if the content of the first phosphor particles is in the range of 0.1% by mass or more and 99.9% by mass or less with respect to the total amount of the first phosphor particles and the inorganic material, a mixed-color light having a desired chromaticity can be obtained by wavelength-converting the excitation light with the substrate containing the first phosphor particles and the second phosphor particles containing particles discontinuously present in the horizontal direction along the surface of the substrate.

[0033] The average particle size of the first phosphor particles is preferably in the range of 1 μm or more and 50 μm or less. The average particle size of the first phosphor particles is more preferably 2 μm or more, more preferably 5 μm or more. The average particle size of the first phosphor particles is more preferably 40 μm or less, further preferably 20 μm or less, and particularly preferably 15 μm or less. When the average particle size of the first phosphor particles is 1 μm or more, the first phosphor particles can be dispersed substantially uniformly in the base. When the average particle size of the first phosphor particles is 50 μm or less, the voids in the base are reduced, so that the wavelength conversion efficiency of the excitation light can be increased. In this specification, the average particle size of the phosphor particles refers to the average particle size (Fisher Sub-Sieve Siezer's Number) measured by the Fisher Sub-Sieve Sizer (hereinafter also referred to as the "FSSS method").

[0034] Second phosphor particles The second phosphor particles emit light in a wavelength range different from that of the first phosphor particles when exposed to light from an excitation light source. The second phosphor particles preferably emit light having an emission peak wavelength in the range of 600 nm to 690 nm. The second phosphor particles are preferably at least one phosphor selected from the group consisting of fluoride phosphors, alkaline earth metal silicon nitride phosphors, and α-sialon phosphors.

[0035] In the molded body, when the first phosphor particles have a peak emission wavelength in the range of 530 nm or more and 590 nm or less, it is preferable that the second phosphor particles have a peak emission wavelength in the range of 600 nm or more and 670 nm or less.

[0036] In the molded body, when the first phosphor particles have a peak emission wavelength in the range of 490 nm or more and 555 nm or less, it is preferable that the second phosphor particles have a peak emission wavelength in the range of 600 nm or more and 690 nm or less.

[0037] When the second phosphor particles are phosphor particles having an emission peak wavelength in the range of 600 nm or more and 690 nm or less by the light from the excitation light source, it is preferably at least one phosphor selected from the group consisting of a fluoride phosphor having a composition represented by the following formula (2A), a fluorogermanate (hereinafter also referred to as "MGF") phosphor contained in a fluoride phosphor having a composition represented by the following formula (2B), an alkaline earth metal silicon nitride phosphor having a composition represented by the following formula (2C), an alkaline earth metal silicon nitride phosphor having a composition represented by the following formula (2D), an α-sialon phosphor having a composition represented by the following formula (2E), and a nitride phosphor having a composition represented by the following formula (2F).

[0038] A2[M 2 1-b Mn 4+ b F6] (2A) In formula (2A), A is at least one selected from the group consisting of an alkali metal element and NH4 + and M 2 is at least one element selected from the group consisting of a Group 4 element and a Group 14 element, and b is a number satisfying 0 < b < 0.2.

[0039] (i-j)MgO·(j / 2)M 3 2O3·kMgF2·mCaF2·(1-n)GeO2·(n / 2)M 4 2O3:zMn 4+ (2B) In formula (2B), M 3 is at least one element selected from the group consisting of Li, Na, K, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, and M 4 is at least one element selected from the group consisting of Al, Ga and In, and i, j, k, m, n and z are numbers respectively satisfying 2 ≦ i ≦ 4, 0 ≦ j < 0.5, 0 < k < 1.5, 0 ≦ m < 1.5, 0 < n < 0.5, and 0 < z < 0.05.

[0040] (Ca1-p Sr p )AlSiN3:Eu (2C) In formula (2C), p is a number satisfying 0 ≦ p ≦ 1.0.

[0041] (Ca 1-q-r Sr q Ba r )2Si5N8:Eu (2D) In formula (2D), q and r are numbers respectively satisfying 0 ≦ q ≦ 1.0, 0 ≦ r ≦ 1.0, and q + r ≦ 1.0.

[0042] M 5 c Si 12-(d+e) Al d+e O e N 16-e :Eu (2E) In formula (2E), M 5 is at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and c, d, and e are numbers respectively satisfying 0 < c ≦ 2.0, 2.0 ≦ d ≦ 6.0, and 0 ≦ e ≦ 1.0.

[0043] M 6 f M 7 g M 8 h Al 3-i Si i N j (2F) In formula (2F), M 6 is at least one element selected from the group consisting of Sr, Ca, Ba, and Mg, M 7 is at least one element selected from the group consisting of Li, Na, and K, M 8 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and f, g, h, i, and j are numbers respectively satisfying 0.80 ≦ f ≦ 1.05, 0.80 ≦ g ≦ 1.05, 0.001 < h ≦ 0.1, 0 ≦ i ≦ 0.5, and 3.0 ≦ j ≦ 5.0.

[0044] When the second phosphor particles are phosphor particles having an emission peak wavelength in the range of 600 nm to 670 nm by light from an excitation light source, specific examples of the second phosphor particles include K2SiF6:Mn, MGF:Mn, Ca2Si5N8:Eu, (Ba,Sr)2Si5N8:Eu, (Sr,Ca)AlSiN3:Eu, CaAlSiN3:Eu, Sr 0.9925 Li 1.0000 EU 0.0075 Examples include Al3N4.

[0045] The average particle size of the second phosphor particles may be in the range of 1 μm to 50 μm. The average particle size of the second phosphor particles is preferably 2 μm or more, more preferably 5 μm or more. The average particle size of the second phosphor particles is preferably 40 μm or less, more preferably 20 μm or less, and even more preferably 15 μm or less. If the average particle size of the second phosphor particles is in the range of 1 μm to 50 μm, the second phosphor particles fixed to the base by the second ceramics derived from the second inorganic binder so as to include particles intermittently present in the horizontal direction along the surface of the base, the first phosphor particles in the base, and the light from the excitation light source provide mixed color light with improved color rendering.

[0046] The second phosphor particles are fixed by the second ceramic so that unevenness due to the second phosphor particles is formed on the surface of the base. The second phosphor particles are fixed to the surface of the base by the translucent second ceramic derived from the second inorganic binder described later. As described later, the second inorganic binder contains a second ceramic precursor that becomes the second ceramic and a solvent. The second phosphor particles are mixed with the second inorganic binder to form a phosphor-containing composition, and the phosphor-containing composition is applied to the surface of the base by a method described later. The second phosphor particles tend to be easily aggregated in the phosphor-containing composition by the solvent contained in the second inorganic binder. When the solvent volatilizes, the second ceramic precursor contained in the second inorganic binder is easily present between the aggregated second phosphor particles, the second phosphor particles, and the base due to the action of capillary action or surface tension. Therefore, the second phosphor particles are arranged on the surface of the base so as to include particles that are present intermittently in the horizontal direction along the surface of the base. Then, by subsequent heat treatment, the second phosphor particles are fixed to the surface of the base by a translucent second ceramic derived from the second inorganic binder so as to include particles that are present intermittently in the horizontal direction along the surface of the base, and unevenness caused by the second phosphor particles is formed on the surface.

[0047] Second ceramics derived from second inorganic binder The second ceramics having translucency derived from the second inorganic binder is obtained by heat-treating the second ceramics precursor contained in the inorganic binder. The second ceramics precursor is preferably a silica precursor. The silica precursor is preferably polysilanol or polysilazane. The second ceramics is preferably silicon dioxide (SiO2), but alumina (Al2O3) can also be used. Polysilanol is a compound containing a siloxane (Si-O-Si) bond, and by heat treatment, the hydroxyl group and alkoxy group bonded to Si are removed to become silicon dioxide (SiO2) having translucency, which fixes the second phosphor particles to each other or the second phosphor particles to the base. Polysilazane is a compound containing a SiH2-NH bond, and by heat treatment in the air or in an atmosphere containing water vapor, it reacts with moisture and oxygen to become silicon dioxide (SiO2) having translucency, which fixes the second phosphor particles to each other or the second phosphor particles to the base.

[0048] The second ceramics, which fix the second phosphor particles arranged so as to form unevenness due to the second phosphor particles on the surface, form a layered material on the surface of the base. The layered material may not be a layer of uniform thickness. The thickness of the layered material including the second phosphor particles and the second ceramics may be in the range of 1 μm to 180 μm, 1 μm to 150 μm, 2 μm to 120 μm, or 2 μm to 100 μm. In the present specification, the thickness of the layered material may be measured by a contact thickness measuring device, or more accurately, it may be confirmed by observing the cross section with a SEM.

[0049] Third phosphor particles The molded body may further include third phosphor particles on the surface of the base, which emit light in a wavelength range different from that of the second phosphor particles. When the molded body includes the third phosphor particles on the surface of the base, the excitation light that passes through the base without being wavelength-converted by the first phosphor particles can be further wavelength-converted by the third phosphor particles on the surface of the base, and mixed-color light having a desired chromaticity can be obtained from the molded body. The third phosphor particles may be fixed with a third ceramic, which will be described later.

[0050] The third phosphor particles may be ones that convert the wavelength of light from the first phosphor particles or the second phosphor particles, but are preferably ones that convert the wavelength of light from an excitation light source. The excitation light that passes through the base without being wavelength-converted by the first phosphor particles contained in the base can be wavelength-converted by the third phosphor particles, and a mixed color light having a desired chromaticity can be obtained from the molded body by the excitation light that passes through the base, the light that has been wavelength-converted by the first phosphor particles, the light that has been wavelength-converted by the second phosphor particles, and the light that has been wavelength-converted by the third phosphor particles. The emission color from the third phosphor particles is the same as or close to the emission color of the first phosphor particles, so that the emission color of the first phosphor particles is supplemented, and the color of the light emitted from the light emitting device can be shifted toward the emission color of the first phosphor particles.

[0051] The third phosphor particles may be phosphor particles having a peak emission wavelength in the range of 530 nm or more and 590 nm or less when exposed to light from an excitation light source, or may be phosphor particles having a peak emission wavelength in the range of 490 nm or more and 555 nm or less.

[0052] When the third phosphor particles are phosphor particles having an emission peak wavelength in the range of 530 nm to 590 nm by light from an excitation light source, the third phosphor particles may be at least one type of aluminate phosphor. Examples of the aluminate phosphor include an aluminate phosphor having a composition represented by the above formula (1A). When the third phosphor particles are phosphor particles having an emission peak wavelength in the range of 530 nm to 590 nm by light from an excitation light source, the third phosphor particles may be Y3Al5O 12 : Ce, Y3(Al,Ga)5O12 : Ce, (Y, Gd)3Al5O 12 : Ce, Lu3A l5 O 12 : Ce, or Lu3(Al, Ga)5O 12 : Examples include Ce.

[0053] When the third phosphor particles are phosphor particles having an emission peak wavelength in the range of 490 nm or more and 555 nm or less by the light from the excitation light source, it is preferably at least one phosphor selected from the group consisting of alkaline earth metal silicate phosphors, alkaline earth metal aluminate phosphors, alkaline earth metal halosilicate phosphors, and β - sialon phosphors. When the third phosphor particles are phosphor particles having an emission peak wavelength in the range of 490 nm or more and 555 nm or less by the light from the excitation light source, it may be at least one selected from the group consisting of an alkaline earth metal silicate phosphor having the composition represented by the formula (1B), an alkaline earth metal aluminate phosphor having the composition represented by the formula (1C), an alkaline earth metal halosilicate phosphor having the composition represented by the formula (1D), and a β - sialon phosphor having the composition represented by the formula (1E). When the third phosphor particles are phosphor particles having an emission peak wavelength in the range of 490 nm or more and 555 nm or less by the light from the excitation light source, specifically, as the third phosphor particles, BaSi2O2N2:Eu, Sr4Al 14 O 25 : Eu, Ca8MgSi4O 16 Cl2:Eu, Si 6-a Al a O a N 8-a : Eu (where a is a number satisfying 0 < a < 4.2) can be mentioned.

[0054] In plan view, when the unit area of ​​the surface of the base is 100%, the total surface area where the second phosphor particles and the third phosphor particles are present is preferably 97% or less, more preferably 90% or less, even more preferably 80% or less, even more preferably 78% or less, and particularly preferably 72% or less. In addition, when the unit area of ​​the surface of the base is 100%, the total surface area where the second phosphor particles and the third phosphor particles are present is preferably 10% or more, more preferably 20% or more, even more preferably 25% or more, even more preferably 30% or more, and particularly preferably 35% or more. In plan view of the molded body, the total surface area where the second phosphor particles and the third phosphor particles are present relative to 100% of the unit area of ​​the surface of the base is also called the coverage rate. When viewed in a plan view, if the total surface area in which the second phosphor particles and the third phosphor particles are present on the surface of the base is 97% or less relative to 100% unit area of ​​the surface of the base, light whose wavelength has been converted by the first phosphor particles in the base and light from an excitation light source that has passed through the translucent base without being wavelength converted by the first phosphor particles can be extracted from areas where the second phosphor particles and the third phosphor particles are not present, and mixed light having the desired chromaticity can be obtained from the molded body by using this light and the light whose wavelength has been converted by the second phosphor particles and the third phosphor particles, thereby satisfying the requirement for thinness.

[0055] The second and third phosphor particles intermittently present along the surface of the substrate, and the second ceramic form a layered material on the surface of the substrate. The layered material may not be a layer of uniform thickness. The thickness of the layered material including the second and third phosphor particles and the second ceramic may be in the range of 1 μm to 180 μm, 1 μm to 150 μm, 2 μm to 120 μm, or 2 μm to 100 μm. The maximum height of the second phosphor particles and the second ceramic is preferably in the range of 1 μm to 150 μm.

[0056] Third Ceramics The third ceramic is preferably a light-transmitting member derived from the third inorganic binder, and is preferably obtained by heat-treating the third ceramic precursor contained in the third inorganic binder. The third inorganic binder is preferably the same as the first inorganic binder or the second inorganic binder, but may be different. The third ceramic precursor is preferably a silica precursor. The third ceramic is preferably silicon dioxide (SiO2) derived from the silica precursor contained in the third inorganic binder, but alumina (Al2O3) can also be used. The third ceramic is preferably composed of a third ceramic formed by applying the third inorganic binder on the second phosphor particles and the second ceramic, or on the second phosphor particles, the third phosphor particles, and the second ceramic by spin coating, and then heat-treating the third inorganic binder.

[0057] The thickness of the third ceramic is not particularly limited, but in order to emit light transmitted through the base and light whose wavelength has been converted by the first phosphor particles, the second phosphor particles, or the third phosphor particles, the thickness from the base to the upper surface of the third ceramic is preferably within a range of 2 μm to 100 μm. The thickness from the base to the upper surface of the third ceramic may be within a range of 3 μm to 70 μm, or may be within a range of 5 μm to 50 μm.

[0058] The fourth ceramic The fourth ceramic is preferably a translucent fourth ceramic formed by atomic layer deposition (ALD). The fourth ceramic is preferably aluminum oxide (Al2O3). When the fourth ceramic is formed by ALD, it has a uniform thickness and can be densely formed, so that the adhesion between the second phosphor particles or the third phosphor particles and the base can be increased, and the second phosphor particles or the third phosphor particles can be prevented from falling off or peeling off. The thickness of the fourth ceramic may be, for example, in the range of 0.5 nm to 100 nm, or in the range of 1 nm to 50 nm.

[0059] Light-emitting device A light emitting device includes the molded article and an excitation light source. The light emitting device can be used as a light source for a projector, an illumination device, a display device, or the like.

[0060] The excitation light source is preferably a light emitting element made of a light emitting diode (LED) or a semiconductor laser (LD) chip, and is preferably a nitride semiconductor (In X Al Y Ga 1-X-Y N, 0≦X, 0≦Y, X+Y≦1) can be used. By using a semiconductor light-emitting element as the excitation light source, it is possible to obtain a stable light-emitting device that is highly efficient, has high linearity of output relative to input, and is resistant to mechanical shock.

[0061] The excitation light source is preferably a semiconductor laser. The excitation light emitted from the semiconductor laser as the excitation light source is made incident on the molded body, and the light whose wavelength is converted by the molded body is condensed, and separated into red light, green light, and blue light by a plurality of optical systems such as a lens array, a polarization conversion element, and a color separation optical system, and modulated according to image information to form color image light. The excitation light emitted from the semiconductor laser as the excitation light source may be made incident on the molded body through an optical system such as a dichromic mirror or a collimating optical system.

[0062] The light emitting device preferably has an average color rendering index Ra of 70 or more. The average color rendering index Ra of the light emitting device is more preferably 71 or more, and even more preferably 72 or more. The average color rendering index Ra of the light emitting device can be measured in accordance with JIS Z8726. The closer the average color rendering index Ra of the light emitting device is to 100, the closer the color rendering is to that of the reference light source. If the average color rendering index Ra is 70 or more, it is possible to provide a light emitting device that emits light suitable for illumination purposes for general work in offices, schools, etc.

[0063] Light emitting device (light emitting module) A light-emitting device including a molded body and an excitation light source, and a light-emitting module including a light-emitting device will be described. The light-emitting device is not limited to the light-emitting module described below. The dimensions, materials, shapes, and relative arrangements of the components of the light-emitting device and light-emitting module described below are merely examples, and are not intended to be limited to the following descriptions unless otherwise specified. Note that the sizes and positional relationships of the components shown in each drawing may be exaggerated to clarify the description. Also, the light-emitting elements shown in each drawing are illustrated with a number set as an example to make the configuration easier to understand.

[0064] Fig. 6A is a schematic perspective view showing the configuration of a light emitting module, which is an example of a light emitting device, including a light emitting device having a molded body and an excitation light source. Fig. 6B is a schematic plan view showing the configuration of a light emitting module, which is an example of a light emitting device, including a light emitting device having a molded body and an excitation light source. Fig. 6C is a cross-sectional view taken along line VIC-VIC in Fig. 6B. Fig. 6D is a cross-sectional view taken along line VID-VID in Fig. 6B. Fig. 6E is a schematic cross-sectional view showing the configuration of an example of a light emitting device. Fig. 6F is a schematic bottom view showing the configuration of an example of a light emitting device.

[0065] A light emitting module 200, which is an example of a light emitting device, includes a light emitting device 100 and a module substrate 80 on which the light emitting device 100 is mounted.

[0066] Light-emitting device The light emitting device 100 will now be described. The light emitting device 100 has a plurality of light emitting surfaces on the upper surface thereof as light extraction regions of the light emitting device 100 . The light emitting device 100 includes a submount substrate 10, a light emitting element 20 provided on the submount substrate 10, a light transparent member 30 made of the above-mentioned molded body provided on the light emitting element 20, a light guiding member 40 disposed between the light transparent member 30 and the light emitting element 20, an element structure 15 including a first covering member 50 covering a side surface of the light emitting element 20 on the submount substrate 10, and a second covering member 60 covering a side surface of the element structure 15 and holding a plurality of element structures 15. The upper surface of the light transparent member 30 is exposed from the second covering member 60 and constitutes a plurality of light emitting surfaces provided in the light emitting device 100. In the light emitting device 100, a plurality of element structures 15, each having a light emitting surface, are held by a second covering member 60. The second covering member 60 makes it possible to hold each of the element structures 15 in a desired arrangement, so that the plurality of light emitting surfaces can be arranged at a smaller distance and with a higher density. The light emitting device 100 may not use the light guiding member 40, and the light transparent member 30 and the light emitting element 20 may be directly bonded to each other.

[0067] Each component of the light emitting device 100 will now be described. The submount substrate 10 is a member on which the light emitting element 20 and the protective element 25 are mounted. The submount substrate 10 is formed, for example, in a substantially rectangular shape in a plan view. For the submount substrate 10, it is preferable to use an insulating material and a material that is difficult to transmit light emitted from the light emitting element 20 and external light. For example, ceramics such as alumina, aluminum nitride, mullite, etc., thermoplastic resins such as polyamide, polyphthalamide, polyphenylene sulfide, liquid crystal polymer, etc., and resins such as epoxy resin, silicone resin, modified epoxy resin, urethane resin, phenol resin, etc. Among them, it is preferable to use ceramics that have excellent heat dissipation properties.

[0068] The submount substrate 10 has wiring on the upper surface, the lower surface, and inside thereof for electrically connecting to the light emitting element 20 and an external power supply. The wiring can be formed using, for example, a metal such as Fe, Cu, Ni, Al, Ag, Au, Al, Pt, Ti, W, or Pd, or an alloy containing at least one of these metals. For example, the submount substrate 10 may include a substrate having an upper surface wiring 2 connected to the light emitting element 20 on the upper surface on which the light emitting element 20 is mounted, and an external connection electrode 3 (e.g., an anode electrode 3a and a cathode electrode 3b) electrically connected to an external power source on the lower surface opposite to the upper surface on which the light emitting element 20 is mounted. In this case, the upper surface wiring 2 and the external connection electrode 3 may be formed with a via 4 that extends to both the upper surface and the lower surface, that is, that penetrates the submount substrate 10. This electrically connects the upper surface wiring 2 and the external connection electrode 3.

[0069] In the light emitting device 100, the distance L1 between adjacent submount substrates 10 may be, for example, 0.05 mm or more and 0.2 mm or less. As a result, the thickness of the second covering member 60 disposed between the submount substrates 10 is 0.05 mm or more and 0.2 mm or less, so that the adjacent submount substrates 10 can be densely joined to each other. Also, in the light emitting device 100 including a plurality of element structures 15, each of the plurality of element structures 15 includes a submount substrate 10, and the second covering member 60 can be disposed between the submount substrates 10. As a result, it is possible to suppress the influence of thermal stress due to expansion or contraction of the submount substrate 10 caused by heat generated in each element structure 15 and thermal history during mounting of the light emitting device.

[0070] The light emitting element 20 is a semiconductor element that emits light by itself when a voltage is applied. The shape, size, etc. of the light emitting element 20 can be selected as desired. The light emitting element 20 can be selected to emit light of any wavelength depending on the application. For example, the light emitting element 20 for blue (light with a wavelength of 430 nm to 500 nm) or green (light with a wavelength of 500 nm to 570 nm) can be made of the above-mentioned nitride semiconductor (In X Al Y Ga 1-X-YN, 0≦X, 0≦Y, X+Y≦1), GaP, etc. can be used. As the red light emitting element 20 (light with a wavelength of 610 nm to 700 nm), in addition to the nitride-based semiconductor element, GaAlAs, AlInGaP, etc. can be used. As the excitation light source, a semiconductor laser is preferable among the semiconductor light emitting elements, but a light emitting diode can also be used.

[0071] It is preferable to use light emitting element 20 having positive and negative element electrodes on one surface, which allows flip chip mounting to wiring on submount substrate 10 with conductive adhesive 8. As conductive adhesive 8, for example, eutectic solder, conductive paste, bumps, etc. may be used.

[0072] The protective element 25 is, for example, a Zener diode. The protective element 25 has positive and negative element electrodes on one surface, and is flip-chip mounted to wiring on the submount substrate 10 with a conductive adhesive 8. The light emitting device may not include the protective element 25.

[0073] The above-mentioned molded body can be used for the light-transmitting member 30. The light-transmitting member 30 is a flat plate-like member having an upper surface that is the main light-emitting surface of each element structure 15 and the light-emitting device 100, and a lower surface opposite to the upper surface. The light-transmitting member 30 is disposed on the light-emitting element 20. The light-transmitting member 30 preferably has an upper surface that is wider than the upper surface of the light-emitting element 20, and is preferably disposed so as to enclose the light-emitting element 20 in a planar view. In the light emitting device 100, the distance L2 between the light transparent members 30 exposed on the upper surface of the light emitting device 100 may be, for example, 0.2 mm or less. If the distance L2 between adjacent light transparent members 30 is 0.2 mm or less, the light source can be made smaller. The distance L2 between adjacent light transparent members 30 may be 0.1 mm or less, or 0.05 mm or less. From the viewpoint of ease of manufacturing the light emitting device 100, the distance L2 between the light transparent members 30 may be 0.03 mm or more.

[0074] The planar shape of the light-transmitting member 30 may be various, such as a circle, an ellipse, a square, or a polygon such as a hexagon. Among them, from the viewpoint of arranging a plurality of light-emitting surfaces in close proximity, a rectangular shape such as a square or a rectangle is preferable, and a shape similar to the planar shape of the light-emitting element 20 is more preferable.

[0075] The light guiding member 40 is disposed between the light transmitting member 30 and the light emitting element 20, and is a member that joins the light emitting element 20 and the light transmitting member 30. The light guiding member 40 is a member that facilitates extraction of light from the light emitting element 20 and guides the light from the light emitting element 20 to the light transmitting member 30. The light guiding member 40 can improve the luminous flux and the light extraction efficiency. The light guiding member 40 is preferably provided also on the side surface of the light emitting element 20. The light guide member 40 covering the side surface of the light emitting element 20 can be formed by spreading the adhesive member that bonds the light transmitting member 30 and the light emitting element 20 onto the side surface of the light emitting element 20 .

[0076] The light guide member 40 is formed in a triangular shape in a cross-sectional view such that the width of the member increases from the lower surface (submount substrate 10 side) of the light emitting element 20 toward the light transparent member 30. With this configuration, the light traveling in the lateral direction from the light emitting element 20 is more likely to be reflected upward, thereby further improving the luminous flux and light extraction efficiency. However, the cross-sectional shape of the outer surface of the light guide member 40 is not limited to a linear shape, and may be a curved shape. For example, the curved shape of the light guide member 40 may be a curved shape that bulges toward the first covering member 50 side, or a curved shape that is recessed toward the light emitting element 20 side.

[0077] The light-guiding member 40 need only cover the area of ​​the side surface of the light-emitting element 20 that includes the light-emitting portion, but from the viewpoint of improving the luminous flux and light extraction efficiency, it is more preferable that the light-guiding member 40 covers substantially the entire side surface of the light-emitting element 20. For example, a light-transmitting resin material, glass, or ceramics can be used as the light-guiding member 40. The light-guiding member 40 may contain a diffusing material. This allows light to be more uniformly incident on the light-transmitting member 30, and prevents color unevenness in the light-emitting device 100.

[0078] The first covering member 50 is provided on the submount substrate 10 and covers the side surface of the light emitting element 20. The first covering member 50 can increase the adhesive strength between the submount substrate 10 and the light emitting element 20. The first covering member 50 covers the side surface of the light emitting element 20 via the light guiding member 40. The first covering member 50 is formed, for example, in a triangular cross-sectional shape so that the member width increases from the light transmitting member 30 side toward the submount substrate 10 in a cross-sectional view. The cross-sectional shape of the outer surface of the first covering member 50 is not limited to a linear shape, and may be a curved shape. For example, the curved shape of the first covering member 50 may be a curved shape that bulges toward the second covering member 60 side, or a curved shape that is recessed toward the light emitting element 20 side.

[0079] As the first covering member 50, for example, a light-transmitting resin material containing a reflective material can be used. Examples of the resin material used for the first covering member 50 include silicone resin, epoxy resin, and urea resin. In particular, it is preferable to use silicone resin, which has excellent light resistance and heat resistance. Examples of the reflective material include titanium oxide, silica, silicon oxide, aluminum oxide, zirconium oxide, magnesium oxide, potassium titanate, zinc oxide, silicon nitride, and boron nitride. Among them, it is preferable to use titanium oxide, which has a relatively high refractive index, from the viewpoint of light reflection.

[0080] The first covering member 50 may cover at least a part of the side surface of the light emitting element 20. Preferably, the first covering member 50 covers the entire side surface of the light emitting element 20. More preferably, the first covering member 50 extends from the side surface of the light emitting element 20 to cover at least a part of the side surface of the light transparent member 30. This can prevent light from the side surface of the light emitting element 20 from being directly emitted to the outside in each element structure 15. This can prevent light leakage to adjacent element structures 15 in a light emitting device 100 including a plurality of element structures 15, resulting in a light emitting device 100 with less uneven light emission. In addition, as described below, when a sorting process is performed after the element structures 15 are separated into individual elements, the chromaticity coordinates of the element structures 15 can be more easily grasped. Moreover, the first covering member 50 preferably covers the lower surface of the light emitting element 20. This allows light traveling downward from the light emitting element 20 to be irradiated to and reflected by the reflecting material contained in the first covering member 50, thereby further increasing the luminous flux of the light emitting device 100. In addition, the adhesive strength between the submount substrate 10 and the light emitting element 20 can be further increased.

[0081] The second covering member 60 is a member provided around the plurality of element structures 15. The second covering member 60 is preferably made of a resin material, but glass or ceramics can also be used. The second covering member 60 is formed by covering the side surfaces of the element structures 15 with, for example, a white resin made of a translucent resin material containing a reflective material. That is, the second covering member 60 covers the side surfaces of the submount substrate 10, the side surfaces of the first covering member 50, and the side surfaces of the light-transmitting member 30. The second covering member 60 is also provided between adjacent element structures 15, and covers the outer peripheral side surfaces of each of the plurality of element structures 15 while exposing the upper surface of the light-transmitting member 30.

[0082] Examples of the resin material used for the second covering member 60 include the resin materials exemplified for the first covering member 50. Examples of the reflective material contained in the resin used for the second covering member 60 include the reflective materials exemplified for the first covering member 50.

[0083] The light emitting device 100 includes a plurality of element structures 15, each of which includes a first covering member 50 covering a side surface of the light emitting element 20, and therefore can suppress lateral leakage of light emitted from the light emitting element 20. This makes it possible to arrange the plurality of element structures 15 closer to each other without reducing the light extraction efficiency of each element structure 15. In the light emitting device 100, as an example here, four element structures 15 arranged in a matrix of two rows and two columns are held by a second covering member 60. The element structures 15 are arranged so that the protective elements 25 are positioned on the outer side. This allows the four light-transmitting members 30 to be arranged in a matrix with narrower intervals. The light emitting device may include three or less element structures 15, or may include five or more element structures 15.

[0084] Method for manufacturing a light emitting device The manufacturing method of the light emitting device 100 includes an element structure preparation step of preparing a plurality of element structures 15 each including a submount substrate 10, a light emitting element 20 provided on the submount substrate 10, a light transmitting member 30 provided on the light emitting element 20, a light guiding member 40 provided on the side of the light emitting element 20, and a first covering member 50 covering the side of the light emitting element 20 on the submount substrate 10, an element structure mounting step of mounting the plurality of element structures 15 on a sheet member so that the submount substrate 10 of the element structure 15 faces the sheet member, a second covering member formation step of forming a second covering member 60 on the sheet member that covers the side of the plurality of element structures 15 and holds the plurality of element structures 15, and a sheet member removal step of removing the sheet member. The manufacturing method of the light emitting device may include the above-mentioned molded body as the light transmitting member 30, as well as the manufacturing method described in Japanese Patent Application No. 2020-006262.

[0085] Light Emitting Module Next, a light emitting module 200, which is a light emitting device, will be described. The light emitting module 200 includes the light emitting device 100 having the configuration already described, and a module substrate 80 on which the light emitting device 100 is mounted so that the submount substrate 10 of the light emitting device 100 faces the module substrate 80. In the case where the light emitting device 100 does not include the protective element 25, the protective element 25 may be provided on the module substrate 80. The module substrate 80 may also be configured to include electronic components other than the protective element 25.

[0086] The light emitting device 100 has the configuration as described above. The module substrate 80 is a member on which the light emitting device 100 is mounted, and electrically connects the light emitting device 100 to the outside. The module substrate 80 is formed, for example, in a substantially rectangular shape in a plan view. As the material of the module substrate 80, for example, the materials exemplified as those used for the submount substrate 10 can be mentioned. The module substrate 80 has wiring on its upper surface for electrically connecting to the light emitting device 100. Examples of materials for the wiring of the module substrate 80 include the materials exemplified as those used for the wiring of the submount substrate 10. A composite material of an insulating material and a metal member may also be used.

[0087] The light emitting device 100 is mounted on the upper surface of the module substrate 80 such that the wiring of the submount substrate 10 and the wiring of the module substrate 80 are bonded via a conductive adhesive. As the conductive adhesive, for example, eutectic solder, conductive paste, bumps, metal sintered bodies, etc. may be used. A metal sintered body, for example, a metal powder such as silver particles sintered at 160°C or higher, preferably 180°C or higher, and 400°C or lower, preferably 280°C or lower, can be used to firmly fix the light emitting device 100.

[0088] When the light emitting module 200 is driven, a current is supplied from an external power source to the light emitting element 20, causing the light emitting element 20 to emit light. Of the light emitted by the light emitting element 20, the light traveling upward is extracted to the outside above the light emitting device 100 via the light transparent member 30. Meanwhile, the light traveling downward is reflected by the submount substrate 10 and extracted to the outside of the light emitting device 100 via the light transparent member 30. Meanwhile, the light traveling laterally is reflected by the first covering member 50 and / or the second covering member 60 and extracted to the outside of the light emitting device 100 via the light transparent member 30.

[0089] Manufacturing method of light emitting module The manufacturing method of the light emitting module 200 may include a light emitting device preparation step of preparing the light emitting device 100 using the manufacturing method of the light emitting device 100, and a light emitting device mounting step of mounting the light emitting device 100 so that the submount substrate 10 faces the module substrate 80. The manufacturing method of the light emitting module as the light emitting device can be referred to the manufacturing method described in Japanese Patent Application No. 2020-006262.

[0090] Manufacturing method of molded body An example of a method for producing a molded body according to an embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a flow chart showing an example of a method for producing a molded body. The method for producing a molded body includes a step S101 of preparing a base, a step S102 of preparing a phosphor-containing composition, a step S103 of applying the phosphor-containing composition to the base, and a step S104 of obtaining a molded body having unevenness due to second phosphor particles formed on its surface. This step includes preparing a light-transmitting base made of an inorganic material selected from a first ceramic, glass, and first phosphor particles and including at least one essential material including the first phosphor particles, preparing a phosphor-containing composition containing second phosphor particles and a second inorganic binder, applying the phosphor-containing composition to the base, subjecting the base and the phosphor-containing composition to a first heat treatment, fixing the second phosphor particles to the surface of the base via the light-transmitting second ceramic derived from the second inorganic binder, and obtaining a molded body having unevenness due to the second phosphor particles formed on its surface.

[0091] 8 is a flow chart showing another example of a method for producing a molded body. The method for producing a molded body may include a step S201 of preparing a base, a step S202 of preparing a phosphor-containing composition, a step S203 of applying the phosphor-containing composition to the base, a step S204 of obtaining a molded body having unevenness formed on the surface due to the second phosphor particles, a step S205 of applying a third inorganic binder, a step S206 of fixing the second phosphor particles via a third ceramic, and a step S207 of fixing a fourth ceramic. In addition, after the step S204 of obtaining the molded body, the method may include a step S205 of applying a third inorganic binder onto the second phosphor particles, and a step S206 of fixing the second phosphor particles via a third ceramic derived from the third inorganic binder. The method for producing a molded body may include, after the step of obtaining a molded body, applying a third inorganic binder onto the second phosphor particles by a spin coating method, and subjecting the third inorganic binder to a second heat treatment to fix the second phosphor particles via a third ceramic having translucency derived from the third inorganic binder. The method for producing a molded body may include fixing the second phosphor particles via the third ceramic, and then fixing a fourth ceramic having translucency by an ALD method. The method for producing a molded body may also include a step of cutting and processing the obtained molded body to a desired size or thickness as necessary.

[0092] Step S101 (S201) of preparing a substrate In the base preparation step, a translucent base made of an inorganic material containing first phosphor particles is prepared. The base may be a commercially available product. The base may be made of first phosphor particles in which the content of the first phosphor particles obtained by sintering the first phosphor particles is 100% by mass, or the content of the first phosphor particles in the base may be within a range of 0.1% by mass to 99.9% by mass. The base used for the molded body may contain at least one inorganic material selected from a first ceramic and glass that do not convert the wavelength of the excitation light, in addition to the first phosphor particles. Specifically, the above-mentioned base may be used. The first phosphor particles may be the same first phosphor particles as the first phosphor particles used for the molded body. The base may be a translucent base containing the first phosphor particles and the first ceramic, which is produced by hardening or firing a first inorganic binder containing the first phosphor particles. The material of the first inorganic binder may be the same as that of the second inorganic binder and the third inorganic binder, so they will be described together. When describing the first inorganic binder, the second inorganic binder, and the third inorganic binder together, they are sometimes called "inorganic binders."

[0093] Step S102 (S202) of preparing a phosphor-containing composition The phosphor-containing composition includes a second phosphor particle and a second inorganic binder. The second phosphor particle may be the same as the second phosphor particle used in the above-mentioned molded body. A third inorganic binder that becomes a third ceramic may be prepared in advance.

[0094] Inorganic Binder At least one of the first inorganic binder which becomes the first ceramic, the second inorganic binder which becomes the second ceramic, and the third inorganic binder which becomes the third ceramic preferably contains a ceramic precursor, and the ceramic precursor is at least one silica precursor selected from polysilanol and polysilazane. Polysilanol is a compound containing a siloxane (Si-O-Si) bond. Polysilazane is a compound containing a SiH2-NH bond. Polysilazane is preferably a perhydropolysilazane in which hydrogen is bonded to all Si or N. The silica precursor contained in the inorganic binder becomes silicon dioxide (SiO2) having translucency by heat treatment. The second inorganic binder fixes the second phosphor particles to each other or the second phosphor particles to the substrate. When the phosphor-containing composition contains the third phosphor particles, the second phosphor particles, the third phosphor particles, and the substrate may be fixed by the second ceramic derived from the second inorganic binder.

[0095] In the step of preparing the phosphor-containing composition, when the phosphor-containing composition is taken as 100 mass%, the content of the ceramic precursor in the phosphor-containing composition is preferably within the range of 0.5 mass% to 70 mass%. If the content of the ceramic precursor in the phosphor-containing composition is within the range of 0.5 mass% to 70 mass%, the inorganic binder containing the ceramic precursor and the phosphor particles can be easily mixed, and the second phosphor particles containing intermittently present particles can be easily fixed to each other or the second phosphor particles and the base with the second ceramic derived from the second inorganic binder.

[0096] The inorganic binder includes a solvent. The amount of the solvent included in the inorganic binder is the remainder obtained by subtracting the amount of the ceramic precursor in the inorganic binder. By heat treatment after applying the inorganic binder, the second phosphor particles or the third phosphor particles are fixed to the surface of the base by the second transparent ceramic derived from the second inorganic binder, or are fixed by the third transparent ceramic derived from the third inorganic binder, so as to include particles that are present intermittently in the horizontal direction along the surface of the base.

[0097] Examples of the solvent contained in the inorganic binder include acetone, ethanol, isopropyl alcohol (IPA), propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), tridecane, and triethylene glycol. The solvent contained in the inorganic binder preferably has a relatively high boiling point, and more preferably has a boiling point of 80° C. or higher at room temperature in the range of 10° C. to 40° C. in an atmospheric pressure (101.325 kPa) atmosphere. If the boiling point of the solvent is relatively high, the volatilization of the solvent can be suppressed when the phosphor-containing composition is applied to the substrate, and the phosphor-containing composition can be evenly applied to the surface of the substrate. If the volatilization of the solvent contained in the inorganic binder can be suppressed, the second phosphor particles flow and aggregate easily in the phosphor-containing composition, and the second phosphor particles are easily arranged on the surface of the substrate so as to include particles that are present intermittently in the horizontal direction along the surface of the substrate. In addition, the solvent contained in the inorganic binder is preferably hydrophilic. When the solvent is hydrophilic, even if the second phosphor particles aggregate in the phosphor-containing composition and are arranged on the surface of the substrate so as to include particles that are present intermittently in the horizontal direction along the surface of the substrate, the ceramic precursor contained in the inorganic binder, together with the hydrophilic solvent, is easily absorbed between the second phosphor particles or between the second phosphor particles and the substrate by the action of capillary action or surface tension, and after the solvent is volatilized by drying, the ceramic precursor is converted into the first ceramic by heat treatment, allowing the second phosphor particles to be fixed to the substrate.

[0098] In addition, the content of the second phosphor particles in 100% by mass of the phosphor-containing composition is preferably in the range of 20% by mass to 99.5% by mass, more preferably in the range of 25% by mass to 98% by mass, even more preferably in the range of 30% by mass to 95% by mass, and particularly preferably in the range of 40% by mass to 90% by mass. If the content of the second phosphor particles in the phosphor-containing composition is in the range of 20% by mass to 99.5% by mass with respect to the total amount of the phosphor-containing composition, the second phosphor particles are easily arranged on the surface of the base by applying the phosphor-containing composition containing an inorganic binder and the second phosphor particles to the base by the method described later, so as to include particles that are intermittently present in the horizontal direction along the surface of the base.

[0099] In the step of preparing the phosphor-containing composition, the phosphor-containing composition may further include a third phosphor particle that emits light in a wavelength range different from that of the second phosphor particle. The third phosphor particle may be the same as the third phosphor particle used in the above-mentioned molded body.

[0100] When the phosphor-containing composition contains the third phosphor particles, the third phosphor particles are contained so that the total content of the second phosphor particles and the third phosphor particles in 100% by mass of the phosphor-containing composition is preferably in the range of 20% by mass to 99.5% by mass, more preferably in the range of 25% by mass to 98% by mass, even more preferably in the range of 30% by mass to 95% by mass, and particularly preferably in the range of 40% by mass to 90% by mass. By containing the third phosphor particles in the phosphor-containing composition, a molded body that emits mixed-color light having a desired chromaticity can be obtained.

[0101] The mass ratio of the second phosphor particles to the third phosphor particles (second phosphor particles:third phosphor particles) in the phosphor-containing composition is preferably within a range of 1:99 to 99:1. If the mass ratio of the second phosphor particles to the third phosphor particles in the phosphor-containing composition is within a range of 1:99 to 99:1, a molded body that emits light of a desired chromaticity can be obtained.

[0102] Step S103 (S203) of applying a phosphor-containing composition to a substrate In the step of applying the phosphor-containing composition to the substrate, the phosphor-containing composition is applied to the substrate by spraying, potting, or printing. Examples of the application method of the phosphor-containing composition include spraying, potting, and printing. Even if the combination of the phosphor-containing composition is such that the particles tend to settle, the spraying method can apply the phosphor-containing composition to the substrate with a stable thickness by using a structure that circulates the slurry. Since the potting method applies the phosphor-containing composition to the substrate by discharging the composition from a syringe, the amount of the phosphor-containing composition applied can be reduced. Although printing has a limitation that it can only be applied to a planar structure, it has a high processing speed and is suitable for mass production. The phosphor-containing composition can be applied to the substrate by appropriately selecting from these application methods.

[0103] In the step of applying the phosphor-containing composition to the substrate, the thickness of the phosphor-containing composition is preferably in the range of 20 μm to 150 μm. The thickness of the phosphor-containing composition on the substrate is not particularly limited by the desired chromaticity, but may be, for example, in the range of 20 μm to 150 μm, may be in the range of 30 μm to 140 μm, or may be in the range of 40 μm to 120 μm. The thickness of the phosphor-containing composition on the substrate can be adjusted by the thickness of the printing mask, for example, when the composition is applied by printing. The phosphor-containing composition may be applied once to the substrate, or may be applied repeatedly multiple times. After the phosphor-containing composition is applied, it may be dried by a drying step described later, and then applied again, or application and drying may be repeated alternately. The phosphor-containing composition may be subjected to at least one drying step between the application steps repeated multiple times.

[0104] A step S104 (S204) of obtaining a molded body having unevenness formed on the surface thereof due to the second phosphor particles. In the process of obtaining a molded body having unevenness on its surface caused by the second phosphor particles, the base and the phosphor-containing composition are subjected to a first heat treatment to fix the second phosphor particles to the surface of the base via a second translucent ceramic derived from the second inorganic binder, thereby obtaining a molded body having unevenness on its surface caused by the second phosphor particles. The method may include a first drying step to remove the solvent contained in the second inorganic binder after applying the phosphor-containing composition to the surface of the substrate and disposing the second phosphor particles on the surface of the substrate so as to include particles that are present intermittently in the horizontal direction along the surface of the substrate. The first drying step is preferably performed, for example, at a temperature range of 50°C to 100°C for 10 minutes to 60 minutes. The first drying step may be repeated multiple times. The solvent may be removed even if the temperature in the first drying step is lower than the boiling point of the solvent contained in the second inorganic binder.

[0105] The temperature for the first heat treatment is preferably within the range of 150° C. to 500° C., more preferably within the range of 180° C. to 400° C., and even more preferably within the range of 200° C. to 350° C. The higher the temperature, the higher the purity of the ceramic precursor becomes, but if the temperature is 350° C. or less, it can be used for phosphors with slightly poor heat resistance.

[0106] The first heat treatment step is preferably carried out in an oxygen-containing atmosphere. The oxygen content in the atmosphere is preferably 5% by volume or more, more preferably 10% by volume or more, and even more preferably 15% by volume or more, and may be an air atmosphere (oxygen content of 20% by volume or more). In an oxygen-free atmosphere in which the oxygen content in the atmosphere is less than 1% by volume, the ceramic precursor contained in the inorganic binder may be difficult to react. The amount of oxygen in the atmosphere may be measured, for example, by the amount of oxygen flowing into a firing device, and may be measured at a temperature of 20°C and atmospheric pressure (101.325 kPa). The heat treatment may be carried out under a slightly reduced pressure of about 100 kPa, which is slightly lower than atmospheric pressure, or may be carried out under atmospheric pressure.

[0107] Step S205 of applying a third inorganic binder After obtaining a molded body in which the second phosphor particles and, in some cases, the third phosphor particles are fixed to the surface of the base with the second ceramic, the third inorganic binder is applied onto the second phosphor particles or the third phosphor particles by a spin coating method. The third inorganic binder can be the same as the first inorganic binder or the second inorganic binder. The conditions for applying the third inorganic binder onto the second phosphor particles of the molded body by the spin coating method are not particularly limited, but the molded body can be rotated at a speed of 500 revolutions / minute (rpm) to 3000 revolutions / minute (rpm) for 30 seconds to 5 minutes to apply the third inorganic binder onto the second phosphor particles or the third phosphor particles. After applying the third inorganic binder onto the second phosphor particles, a second heat treatment step may be included to remove the solvent contained in the third inorganic binder. The second heat treatment step can be performed at the same temperature and time as the second inorganic binder. The second heat treatment step may be repeated multiple times.

[0108] Step S206 of fixing the second phosphor particles via the third ceramic The method may include subjecting the applied third inorganic binder to a second heat treatment to fix the second phosphor particles, and in some cases the third phosphor particles, via a third ceramic having translucency derived from the third inorganic binder. The second phosphor particles, etc. are fixed via the third ceramic. In order to remove the solvent contained in the third inorganic binder, the method may include a second drying step using the same temperature range and drying time as the first drying step.

[0109] The second heat treatment can be performed in the same temperature range and atmosphere as the first heat treatment. The second heat treatment can be performed at the same temperature as the first heat treatment as long as it is in the same temperature range as the first heat treatment, or at a different temperature than the first heat treatment. The second heat treatment can be performed in the same atmosphere as the first heat treatment as long as it is in the same atmosphere as the first heat treatment, or at a different atmosphere than the first heat treatment.

[0110] Step S207 of fixing the fourth ceramic The method for producing a molded body preferably includes fixing the second phosphor particles via the third ceramic, and then fixing a translucent fourth ceramic by the ALD method. The fourth ceramic is preferably formed on the third ceramic. In the method for producing a molded body, by fixing the fourth ceramic on the third ceramic to which the second phosphor particles are fixed, the adhesion between the second phosphor particles or the third phosphor particles, including particles intermittently present in the horizontal direction along the surface of the base, and the base can be further increased, and the second phosphor particles or the third phosphor particles can be prevented from falling off or peeling off. A uniform and dense fourth ceramic can be fixed by the ALD method. When the fourth ceramic is fixed by the ALD method, it is preferable that the material contains a fourth ceramic precursor that becomes the fourth ceramic, and an example of the fourth ceramic precursor that becomes the fourth ceramic is trimethylaluminum. In the ALD method, for example, trimethylaluminum is introduced into the device together with a carrier gas to deposit a trimethylaluminum layer on the third ceramic, and then the trimethylaluminum in the gas phase is removed by purging. Next, water vapor (H2O) is introduced into the device, causing the trimethylaluminum and water vapor to react with each other to adhere the fourth ceramic made of aluminum oxide (Al2O3) as the fourth ceramic.

[0111] Processing process The obtained molded body may be cut into a desired size or thickness. The cutting method may be a known method, such as blade dicing, laser dicing, or cutting using a wire saw. Among these, blade dicing is preferred because it has high dimensional accuracy and does not generate debris.

[0112] Light source device for projector A light emitting device including the molded body and an excitation light source can be used as a light source for a projector. An example of a projector will be described with reference to Fig. 9 and Figs. 10A to 10C. Fig. 9 is a schematic side view showing an overview of a light source device 300 for a projector.

[0113] As shown in Fig. 9, the light source device 300 includes a light source 310, a condenser lens 320 on which light emitted from the light source 310 is incident, a phosphor wheel 330 on which light emitted from the condenser lens 320 is incident, and a light receiving lens 340 on which light emitted from the phosphor wheel 330 is incident. The phosphor wheel 330 is a disc-shaped phosphor wheel that transmits light from the light source, and is rotated by a drive motor 350 via a drive shaft 352. Note that, in Fig. 9, the light source device 300 includes the light source 310, the condenser lens 320, the phosphor wheel 330, and the light receiving lens 340. However, the light source device 300 may be configured by the light source 310, the condenser lens 320, and the phosphor wheel 330 without including the light receiving lens 340.

[0114] Next, an overview of the light source device 300 will be described along the flow of light emitted from the light source 310. In this embodiment, a case where a semiconductor laser that emits blue light is used as the light source 310 will be described as an example. Blue light is emitted from the light source 310, and the emitted blue light enters the condenser lens 320, is condensed by the condenser lens 320, and enters the phosphor wheel 330 rotated by the drive motor 350. The phosphor wheel 330 is made of a material that transmits light, and is provided with a molded body 33 containing phosphor in at least a part of its area. Not limited to the molded body 33, any of the molded bodies 31, 32, 34, and 35 can be used. The phosphor wheel 330 may be divided into an area where the molded body 33 is provided and an area where the molded body 33 is not provided. If the area is divided into an area where molded body 33 is provided and an area where molded body 33 is not provided, when blue light enters phosphor wheel 330 from condenser lens 320, green light of the first phosphor particles, red light of the second phosphor particles, yellow light of the third phosphor particles, and blue light of light source 310 are emitted from phosphor wheel 330 and enter light receiving lens 340. The light is then collimated by light receiving lens 340 and emitted from light source device 300. Note that light receiving lens 340 can not only emit parallel light, but can also emit light in a direction in which the light spreads, or can be condensed at a predetermined position.

[0115] Phosphor Wheel Description 9 and 10A to 10C, the structure of phosphor wheel 330 used in light source device 300 for a projector will be described. As the phosphor provided in phosphor wheel 330, the above-mentioned molded body can be used, and for example, molded body 33 can be used. The phosphor wheel 330 is a transmissive phosphor wheel that transmits light from the light source 310, and includes a first substrate 332 and a second substrate 334 in this order from the light source 310 side. The first substrate 332 and the second substrate 334 are fixed to a drive shaft 352 of a drive motor 350, and rotate around the drive shaft 352 by the driving force of the drive motor 350. That is, the first substrate 332 and the second substrate 334 are fixed in position relative to each other by the drive shaft 352. However, the method of fixing the relative positions of the first substrate 332 and the second substrate 334 is not limited to the case where the drive shaft 352 is used, and they can be fixed by any other means, for example, by inserting a spacer between the first substrate 332 and the second substrate 334. The phosphor wheel 330 includes, for example, a molded body 33 between a first substrate 332 and a second substrate 334. In addition, in the molded body 33 viewed from the arrow B in Fig. 9, it is preferable that a base including the first phosphor particles is disposed on the first substrate 332 side. It is also preferable that the second phosphor particles 102a and the third phosphor particles 102c of the molded body 33 are disposed on the second substrate 334 side.

[0116] The phosphor wheel 330 includes a filter 360 on the light source 310 side that transmits light in the wavelength range of light from the light source 310 and reflects light in the wavelength range of light wavelength-converted by the first phosphor particles, the second phosphor particles, or the third phosphor particles contained in the molded body 33. In the embodiment shown in Fig. 9, the filter 360 is provided on the light source side of the first substrate 332. Specifically, a short-pass filter that transmits light in the blue wavelength range and reflects light in the green, yellow, and red wavelength ranges can be used as the filter 360.

[0117] The phosphor wheel 330 is provided with a filter 362 on the opposite side to the light source 310, which transmits light in the wavelength range of the light wavelength-converted by the first phosphor particles, the second phosphor particles, and the third phosphor particles, and reflects light in the wavelength range of the light from the light source 310. In the embodiment shown in FIG. 9, the filter 362 is provided on the surface of the second substrate 334 opposite to the light source 310, at a position corresponding to the molded body 33 in the rotation direction. Specifically, a long-pass filter that transmits light in the wavelength ranges of green light, yellow light, and red light and reflects blue light can be used as the filter 362. Note that for light in the wavelength range between blue light and red light, for example, light in the wavelength range of yellow light or green light, the filter 362 can transmit or reflect light in a specific wavelength range, and the optimal transmission wavelength range of the filter can be determined depending on the application.

[0118] 10A to 10C, the arrangement on each surface of first substrate 332 and second substrate 334 will be described. Fig. 10A is a diagram showing the light source side surface of first substrate 332 of phosphor wheel 330 as viewed from the arrow A in Fig. 9. First substrate 332 has filter 360 in an area where molded body 33 is provided on the back surface side.

[0119] Fig. 10B is a diagram showing the surface of second substrate 334 of phosphor wheel 330 on the light source side as viewed from the direction of arrow B in Fig. 9. Second substrate 334 is provided with region SP in the rotation direction where molded body 33 is provided, and blue emission region SB where no phosphor is provided.

[0120] 10C is a view showing the surface of the second substrate 334 of the phosphor wheel 330 opposite to the light source as seen from the arrow C in FIG. The second substrate 334 is provided with a filter 362 on the surface opposite to the light source side so as to correspond to the region SP having the molded body 33 on the light source side. Furthermore, the blue emission region SB does not have a phosphor. However, it is also possible to deposit a dielectric multilayer film, form an anti-reflection film, or form a layer containing a scatterer on the blue emission region SB.

[0121] In the phosphor wheel 330 shown in Figures 9 and 10A to 10C, the base of the molded body 33 is arranged on the surface of the first substrate 332 opposite the light source 310, and the second phosphor particles 102a and the third phosphor particles 102c of the molded body are arranged on the surface of the second substrate 334 facing the light source 310.

[0122] Projector Description Next, a case where the above-mentioned light source device 300 is used as a light source device in a so-called one-chip type DLP projector will be described with reference to Fig. 11. Fig. 11 is a schematic diagram showing the configuration of a projector 400 according to one embodiment that includes the above-mentioned light source device 300, and is a schematic plan view of the light source device 300 and the projector 400 as viewed from above. In FIG. 11, light emitted from the light source device 300 enters a DMD (Digital Micromirror Device) element (light modulation means) 470, which is an optical spatial modulator, via an optical system. The light is then reflected by the DMD element 470, condensed by a projection lens 480, which is a projection means, and projected onto a screen 490. The DMD element 470 is a matrix arrangement of fine mirrors, each of which corresponds to a pixel of an image projected onto the screen 490, and can turn on / off the light emitted onto the screen by changing the angle of each mirror in microsecond units. In addition, the gradation of the light incident on the projection lens can be changed depending on the ratio of the time each mirror is turned on to the time it is turned off, thereby enabling gradation display based on the image data of the image to be projected.

[0123] In this embodiment, a DMD element is used as the light modulation means, but this is not limited to this, and any other light modulation element can be used depending on the application. Furthermore, the light source device 300 according to the present invention and the projector 400 using this light source device 300 are not limited to the above-mentioned embodiment, and various other embodiments are included in the present invention. In addition, in this embodiment, the light receiving lens 340 is included in the light source device 300, but this is not limited to the above. For example, the light receiving lens 340 may not be included in the light source device 300, but may be included as part of the optical system.

[0124] As described above, the projector 400 in this embodiment includes the above-mentioned light source device 300, a DMD element 470 that forms an image by sequentially modulating light of multiple wavelength bands emitted from the light source device 300 based on image data, and a projection lens 480 that enlarges and projects the image. By the above steps, a molded article and a light emitting device having excellent color rendering properties and heat resistance can be easily manufactured. EXAMPLES

[0125] The present embodiment will be described in detail below with reference to examples, but the present embodiment is not limited to these examples.

[0126] First phosphor particle a The first phosphor particles a are Y 2.955 Ce 0.045 AlO 12 The rare earth aluminate phosphor particles used had a composition represented by the formula (hereinafter also referred to as "YAG") and an average particle size measured by the FSSS method of 14.9 μm. The first phosphor particles a had an emission peak wavelength in the range of 530 nm to 590 nm. The true density of the YAG first phosphor particles b was 4.60 g / cm 3 It was.

[0127] First phosphor particle b The first phosphor particle b is Lu 2.984 Ce 0.016 AlO 12 The rare earth aluminate phosphor particles used had a composition represented by the formula (hereinafter also referred to as "LAG") and an average particle size of 21.5 μm measured by the FSSS method. The first phosphor particles b had an emission peak wavelength in the range of 490 nm to 555 nm. The true density of the LAG first phosphor particles a was 6.69 g / cm 3 It was.

[0128] Second phosphor particles The second phosphor particles were nitride phosphor particles having a composition represented by (Sr,Ca)AlSiN3:Eu (hereinafter also referred to as "SCASN") and an average particle size of 12.5 μm measured by the FSSS method. The second phosphor particles had an emission peak wavelength in the range of 600 nm to 670 nm.

[0129] Inorganic Binder An inorganic binder containing polysilanol in the range of 1% by mass to 10% by mass and containing isopropyl alcohol as a solvent was used.

[0130] Third phosphor particles The third phosphor particles used were the same as the first phosphor particles.

[0131] Example 1: Preparing a Substrate A substrate was prepared that contained 13 mass% of YAG first phosphor particles a, 87 mass% of aluminum oxide as the first ceramic, had a relative density of 99.7%, and had a thickness of 0.18 mm. In the examples and reference examples, the relative density of the substrate can be calculated based on the following formulas (1) to (3).

[0132] TIFF0007678270000001.tif17170

[0133] TIFF0007678270000002.tif45170

[0134] TIFF0007678270000003.tif19170

[0135] Example 1: Preparing a phosphor-containing composition A phosphor-containing composition was produced by mixing 50% by mass of the second phosphor particles and 50% by mass of the second inorganic binder, with the total amount of the second phosphor particles and the second inorganic binder being 100% by mass. The second inorganic binder contains a silica precursor made of polysilanol as a second ceramic precursor.

[0136] Example 1: Applying a phosphor-containing composition to a substrate The phosphor-containing composition was applied to the surface of the substrate by printing using a mask. The thickness of the mask used was 58 μm. By applying the phosphor-containing composition, the second phosphor particles were arranged on the surface of the substrate. The substrate coated with the phosphor-containing composition was placed on a hot plate and dried at 80° C. for 3 minutes in a first drying step to remove the solvent contained in the second inorganic binder.

[0137] Example 1: Process for obtaining a molded body The substrate coated with the dried phosphor-containing composition was placed on a hot plate and heated stepwise in an air atmosphere (oxygen content of 20 volume % or more, atmospheric pressure 101.325 kPa) at 150°C for 5 minutes, 200°C for 5 minutes, and 250°C for 5 minutes. After heating, the substrate was heat-treated at 300°C for 30 minutes, and the second phosphor particles, including particles present intermittently horizontally along the surface of the substrate, were fixed to the surface of the substrate via a translucent second ceramic made of silicon dioxide derived from the second inorganic binder, to obtain a molded product having unevenness on the surface caused by the second phosphor particles.

[0138] Example 2 A phosphor-containing composition was produced by mixing 55% by mass of the second phosphor particles and 45% by mass of the inorganic binder with respect to the total amount of the second phosphor particles and the inorganic binder being 100% by mass. A molded body having the second phosphor particles fixed to the base via the second ceramic was obtained in the same manner as in Example 1, except that this phosphor-containing composition was used.

[0139] Example 3 A phosphor-containing composition was produced by mixing 60% by mass of the second phosphor particles and 40% by mass of the inorganic binder, with the total amount of the second phosphor particles and the inorganic binder being 100% by mass. A molded body having the second phosphor particles fixed to the base via the second ceramic was obtained in the same manner as in Example 1, except that this phosphor-containing composition was used.

[0140] Example 4 A phosphor-containing composition was produced by mixing 70% by mass of the second phosphor particles and 30% by mass of the inorganic binder with respect to the total amount of the second phosphor particles and the inorganic binder being 100% by mass. A molded body having the second phosphor particles fixed to the base via the second ceramic was obtained in the same manner as in Example 1, except that this phosphor-containing composition was used.

[0141] Example 5 A molded body having second phosphor particles fixed to a base via a second ceramic was obtained in the same manner as in Example 1, except that a substrate similar to that in Example 1 was used and the thickness of the mask used during printing was 116 μm (two masks).

[0142] Reference example 1 A molded body having second phosphor particles fixed to a base via a second ceramic was obtained in the same manner as in Example 1, except that a substrate similar to that in Example 1 was used and the mask thickness during printing was 174 μm (three masks).

[0143] Example 6 As in Example 1, a molded body having second phosphor particles fixed to a base via a second ceramic was obtained, and then the following steps of applying a third inorganic binder and fixing the second phosphor particles via the third ceramic were carried out. Hereinafter, the steps of applying a third inorganic binder and fixing the second phosphor particles via the third ceramic are also referred to as a third ceramic forming step.

[0144] Example 6: Third ceramics formation process A third inorganic binder similar to the second inorganic binder was applied onto the second phosphor particles by spin coating (1000 revolutions per minute (rpm), 30 seconds). After the third inorganic binder was applied, drying was performed once on a hot plate at 80°C for 3 minutes, and the temperature was increased stepwise by leaving it at 150°C for 5 minutes, 200°C for 5 minutes, and 250°C for 5 minutes, and after the temperature increase, it was heat-treated at 300°C for 30 minutes to form a third ceramic, and a molded body was obtained in which the second phosphor particles fixed to the base by the second ceramic were fixed to the base via the third ceramic.

[0145] Example 7 A molded body was obtained in the same manner as in Example 6, except that the step of applying the third inorganic binder and the drying step of the third ceramic formation step were repeated three times in this order, in which the second phosphor particles fixed to the base with the second ceramic were attached to the base via the third ceramic.

[0146] Example 8 As in Example 7, a molded body was obtained in which the second phosphor particles were fixed to the substrate via the second ceramic and then adhered to the substrate via the third ceramic. Then, a SiO2 film was formed on the third ceramic by magnetron sputtering to a thickness of 400.0 nm, forming a translucent fourth ceramic made of silicon dioxide. As a result, a molded body was obtained in which the second phosphor particles were fixed to the substrate via the second ceramic, the third ceramic to which the second phosphor particles were adhered, and the fourth ceramic was formed on the third ceramic.

[0147] Example 9 A SiO2 film was formed on the third ceramic by CVD (Chemical Vapor Deposition) to a thickness of 1200.0 nm, and a translucent fourth ceramic made of silicon dioxide was fixed thereon, but in the same manner as in Example 8, a molded body having the second phosphor particles fixed to the base via the second ceramic, the third ceramic to which the second phosphor particles were fixed, and the fourth ceramic on the third ceramic was obtained. The process of fixing the fourth ceramic on the third ceramic is also referred to as the fourth ceramic forming process.

[0148] Example 10 A film of aluminum oxide (Al2O3) was formed as the fourth ceramic with a thickness of 17.5 nm by heating the substrate at 100°C using trimethylaluminum and water vapor as the fourth ceramic precursor, which is the raw material of the fourth ceramic, on top of the third ceramic by the ALD method, and the fourth ceramic was fixed to a thickness of 17.5 nm by the ALD method. The fourth ceramic was then fixed to a light-transmitting fourth ceramic made of aluminum oxide. In the same manner as in Example 8, a molded body was obtained having second phosphor particles fixed to a substrate via the second ceramic, a third ceramic to which the second phosphor particles were fixed, and a fourth ceramic on the third ceramic.

[0149] Example 11 A substrate was prepared that contained 26.7 mass% of LAG first phosphor particles b, 73.3 mass% of aluminum oxide as the first ceramic, had a relative density of 98.8%, and had a thickness of 0.17 mm. Except for using this substrate, the same procedure as in Example 10 was used to obtain a molded body having second phosphor particles fixed to the substrate via the second ceramic, a third ceramic to which the second phosphor particles were fixed, and a fourth ceramic on the third ceramic.

[0150] SEM images A scanning electron microscope (product name JSM-IT200, manufactured by JEOL) was used to obtain SEM photographs of the plane or cross section of the molded body of each Example and Reference Example. Fig. 12 is a plane SEM photograph of the base on the side where the second phosphor particles exist before the third ceramic and the fourth ceramic are formed according to Example 11. Fig. 13 is a plane SEM photograph of the base on the side where the second phosphor particles exist before the third ceramic and the fourth ceramic are formed according to Example 11, which has been binarized. Fig. 14 is a partial cross-sectional SEM photograph showing the state of the base, the second phosphor particles, and the second ceramic before the third ceramic and the fourth ceramic are formed according to Example 11.

[0151] SEM-EDS elemental mapping On the SEM image, element mapping of elements (Lu, Al, O) contained in the first phosphor particles, elements (Si, O) contained in the first ceramic, elements (Ca, Sr, Al, Si) contained in the second phosphor particles, and elements (Si, O) contained in the second ceramic was prepared by SEM-EDS (scanning electron microscope / energy dispersive X-ray spectrometry). The measurement conditions in SEM-EDS were acceleration voltage: 20 kV, focal length: 11.7 mm, and sample tilt angle: 0°. FIG. 15 is a diagram showing a cross-sectional SEM-EDS mapping showing the state of the base, the second phosphor particles, and the second ceramic before the third ceramic and the fourth ceramic are formed according to Example 11. FIG. 16 is a SEM-EDS element mapping diagram showing the location where Si exists in a partial cross-sectional SEM photograph of the molded body before the third ceramic and the fourth ceramic are formed according to Example 11. Fig. 17 is an SEM-EDS element mapping diagram showing the location of Sr in a partial cross-sectional SEM photograph of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11. Fig. 18 is an SEM-EDS element mapping diagram showing the location of Ca in a partial cross-sectional SEM photograph of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11.

[0152] Surface roughness Ra For each molded body in the Examples and Reference Examples, the surface roughness Ra of the flat surface of the molded body on the side where the second phosphor particles were present was measured using a stylus profiler (product name: Alpha Step IQ3, manufactured by KLA-Tencor) under conditions of a measurement length of 2 mm, a measurement speed of 50 μm / sec, and a Gaussian filter.

[0153] Coverage For each molded body in the Examples and Reference Examples, SEM images (magnification 700x) of the plane of the molded body on the side where the second phosphor particles are present were analyzed using image analysis software (product name: GIMP2, free software), the second phosphor particles were binarized, the area of ​​the SEM image to be measured was set to 100%, and the total area of ​​the binarized second phosphor particles was calculated as the coverage rate of the second phosphor particles.

[0154] Chromaticity x, y and color rendering index Ra due to LED illumination Each molded body of the Examples and Reference Examples was irradiated with blue light having a wavelength of 455 nm from a bullet-shaped LED, and a handy LED spectroradiometer (product: MK-350, manufactured by UPRtek) was used to measure the transmitted light emitted from the side where the second phosphor particles existed in each molded body at room temperature, and the x, y chromaticity coordinates of the chromaticity diagram in the CIE (Commission Internationale de l'eclarirage) 1931 color system were obtained from the measured values. The average color rendering index Ra was measured in accordance with JIS Z8726. The input current when measuring the color rendering index Ra was 20 mA to be the rated forward current, and the forward voltage at that time was 3 V. The results are shown in Table 1.

[0155] Peel test For each molded body of the Examples and Reference Examples, a polyimide tape (product name: No. 360A, manufactured by Nitto Denko Corporation, adhesive strength 408 g / 19 mm) or a dicing tape (product name: D-510T, manufactured by Lintec Corporation, adhesive strength 2200 g / 25 mm) was used to attach the tape to the side of the second phosphor particles fixed to the base via the second ceramic, and a peeling test of the second phosphor particles was performed. The results are shown in Table 2. When the tape was peeled off from the molded body, if the second phosphor particles did not peel off, it was recorded as "no peeling". If a large amount of the second phosphor particles peeled off, it was recorded as "major peeling".

[0156] [Table 1]

[0157] [Table 2]

[0158] The molded bodies according to Examples 1 to 5 had excellent color rendering, with a color rendering index exceeding 70. The molded bodies according to Examples 1 to 5 had a total surface area (coverage) where the second phosphor particles were present of 97% or less relative to 100% unit area of ​​the surface of the base, and a mixed color light of light wavelength-converted by the first phosphor particles in the base, light from an excitation light source that was transmitted through the translucent base without being wavelength-converted by the first phosphor particles, and light wavelength-converted by the second phosphor particles was obtained, and the desired mixed color light could be extracted from the molded body, satisfying the requirement for a thin body.

[0159] The molded body of Reference Example 1 was coated with a phosphor-containing composition by printing using a mask thickness of 174 μm, and the second phosphor particles were fixed to the base with the second ceramics, so that the second phosphor particles that existed intermittently in the horizontal direction along the surface of the base were not included, the second phosphor particles were present over the entire surface of the base, and no unevenness due to the second phosphor particles was formed on the surface. Therefore, the light emitted from the base 101 was wavelength-converted by the second phosphor particles, and the light emitted from the molded body was shifted to the long wavelength side, resulting in a color rendering index of 0.

[0160] According to Table 2, the molded body according to Example 1, which does not have the third ceramic and the fourth ceramic, peels off significantly in the tape peeling test. In contrast, the molded bodies according to Examples 6 and 7, which have the third ceramic and are formed by performing the third ceramic forming process, did not have peeling of the second phosphor particles even in the polyimide tape peeling test. In particular, the molded body according to Example 7, which has been subjected to the coating and drying process three times in the third ceramic forming process, has less peeling of the second phosphor particles in response to the peeling of the dicing tape compared to the molded body according to Example 6, which has been subjected to the coating and drying process once, and an improvement has been observed. Furthermore, the molded bodies according to Examples 8 to 11, which have been subjected to the fourth ceramic forming process, have shown improvement in the molded bodies according to Examples 9 to 11 in response to the peeling of the dicing tape, and further improvement in the molded body according to Example 9, and the molded bodies according to Examples 10 and 11 have no peeling of the second phosphor particles. In the molded bodies according to Examples 10 and 11, it is presumed that the fourth ceramic can be formed by the ALD method in a manner that follows the unevenness of the second phosphor particles, and the adhesion strength of the second phosphor particles is improved.While whether durability in a tape peeling test is necessary when actually using the molded body varies depending on the mode of use, it is desirable for the molded body to have the third ceramic and the fourth ceramic by the third ceramic and fourth ceramic forming step as necessary.

[0161] Chromaticity x, y and color rendering index Ra by LD irradiation The molded body of Example 11 was pulse-irradiated with blue light having a wavelength of 453 nm from the LD (0.05 ms / 5 ms, 3 A, LD output 35 W), and the transmitted light emitted from the side where the second phosphor particles of the molded body of Example 11 existed at room temperature was measured using an integrating sphere measuring device, and from this measurement value, the x, y chromaticity coordinates of the chromaticity diagram in the CIE) 1931 color system were obtained, and further, the average color rendering index Ra was measured in accordance with JIS Z8726. As a result, the chromaticity x = 0.40, the chromaticity y = 0.45, the average color rendering index Ra = 72.9, and the luminous flux = 4508 lm.

[0162] FIG. 12 is a planar SEM photograph of the substrate on the side where the second phosphor particles exist before forming the third ceramic and the fourth ceramic according to Example 11. On the surface of the substrate according to Example 11, the second phosphor particles fixed by the second ceramic exist intermittently on the surface of the molded body, and the surface of the molded body has irregularities due to the second phosphor particles. Therefore, in the molded body according to Example 11, the light transmitted through the substrate is wavelength-converted in the portion where the second phosphor particles exist, and a part of the light transmitted through the substrate and a part of the light wavelength-converted by the first phosphor particles of the substrate are emitted to the outside of the molded body as they are without being wavelength-converted by the second phosphor particles. Therefore, a mixed color light of the light wavelength-converted by the second phosphor particles, the light of the excitation light transmitted through the substrate as it is, and the light wavelength-converted by the first phosphor particles can be obtained from the molded body. In addition, the molded body according to Example 11 had excellent color rendering properties, with the color rendering index Ra exceeding 70 when irradiated with LED or LD.

[0163] 13 is a diagram showing a state where a planar SEM photograph of the base on the side where the second phosphor particles exist before forming the third ceramic and the fourth ceramic in Example 11 is binarized, and the total area of ​​the binarized second phosphor particles, in which the area of ​​the SEM image to be measured is set to 100%, was 66.9%. In the horizontal direction along the surface of the molded body, binarization was performed on the part where the second phosphor particles 102a existed and the part where the second phosphor particles did not exist and the surface of the base 101 could be confirmed. In the part where the second phosphor particles of the molded body did not exist, the surface of the base 101 could be confirmed, so the second phosphor particles did not exist with voids in the horizontal direction along the surface of the base, and the second phosphor particles were not in a state where the second phosphor particles existed with voids in the horizontal direction along the surface of the base. Therefore, in the molded body, the light transmitted through the base was wavelength-converted in the portion where the second phosphor particles were present, and a part of the light transmitted through the base and a part of the light wavelength-converted by the first phosphor particles of the base were emitted to the outside of the molded body as they were without being wavelength-converted by the second phosphor particles. Therefore, a mixed color light of the light wavelength-converted by the second phosphor particles, the light of the excitation light transmitted through the base as it was, and the light wavelength-converted by the first phosphor particles could be obtained from the molded body.

[0164] 14 is a SEM photograph of a cross section of a part of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11. In the molded body before the third ceramic and the fourth ceramic are formed according to Example 11, in the horizontal direction along the surface of the base 101, a part E where the second phosphor particles 102a are intermittently present and a part N where the second phosphor particles are not present can be confirmed, and the surface has irregularities caused by the second phosphor particles 102a. It was also confirmed that the base 101 contains the first phosphor particles 101a and the first ceramics 101b.

[0165] FIG. 15 is an SEM-EDS element mapping diagram of a partial cross-sectional SEM photograph of a molded body before forming the third ceramic and the fourth ceramic according to Example 11. In the surface of the base 101, Sr and Ca, which are elements constituting the second phosphor particles 102a, were detected in the portion where the second phosphor particles 102a exist, and Si contained in the second ceramic that fixes the second phosphor particles 102a and the base 101 or the second phosphor particles 102a to each other was detected around the second phosphor particles 102a. Sr and Ca constituting the second phosphor particles 102a were not detected in the portion N where the second phosphor particles 102a do not exist along the horizontal direction of the surface of the base 101. In addition, almost no Si contained in the second ceramic 102b was detected in the portion N where the second phosphor particles 102a do not exist along the horizontal direction of the surface of the base 101. Lu constituting the first phosphor particles 101a was detected in the portion of the base 101 where the first phosphor particles 101a existed. Moreover, Si constituting silicon dioxide (SiO2) of the second ceramics 102b was detected in the portion of the base 101 where the second ceramics 102b existed.

[0166] FIG. 16 is an SEM-EDS element mapping diagram showing the location of Si in a partial cross-sectional SEM photograph of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11. FIG. 17 is an SEM-EDS element mapping diagram showing the location of Sr in a partial cross-sectional SEM photograph of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11. FIG. 18 is an SEM-EDS element mapping diagram showing the location of Ca in a partial cross-sectional SEM photograph of a molded body before the third ceramic and the fourth ceramic are formed according to Example 11. Comparing FIG. 16 to FIG. 18, the location of Si contained in the second ceramic 102b (SiO2) and the location of Sr and Ca contained in the second phosphor particle ((Sr,Ca)AlSiN3:Eu) are almost the same location, and it was confirmed that the second phosphor particle 102a was fixed by the second ceramic 102b.

[0167] The molded bodies according to the examples and the reference examples all showed a large surface roughness Ra exceeding 5 μm. From this result, it was confirmed that the molded bodies according to the examples and the reference examples all had surface roughness due to the second phosphor particles. The surface of a light-transmitting base made of an inorganic material containing general first phosphor particles on whose surface the surface is not formed with surface roughness due to the second phosphor particles has a surface roughness Ra of 1 μm or less even on a roughly polished surface, and even if particles are applied to the polished surface using a resin binder, the surface roughness Ra is 2 μm or less. The second ceramic derived from the second inorganic binder that fixes the second phosphor particles is very thin as shown in the SEM image of FIG. 12, and since the second phosphor particles fixed by the second ceramic have surface roughness, the molded body has a large surface roughness Ra. If the light extraction surface has surface roughness, the light extraction efficiency is improved, and such an effect can also be expected. In addition, since the second ceramic is used to fix the second phosphor particles, the heat resistance is superior compared to the case where an organic material is used to fix the second phosphor particles. [Industrial Applicability]

[0168] The molded article according to one embodiment of the present invention can be used as a wavelength conversion member for light-emitting devices used in lighting devices for in-vehicle or general lighting, backlights for liquid crystal display devices, and light sources for projectors, in combination with an excitation light source such as an LED or LD. [Explanation of symbols]

[0169] 2: upper surface wiring, 3: external connection electrode, 3a: anode electrode, 3b: cathode electrode, 4: via, 8: conductive adhesive, 10: submount substrate, 15: element structure, 20: light emitting element, 25: protective element, 30: light transmitting member (molded body), 31, 32, 33, 34, 35: molded body, 40: light guiding member, 50: first covering member, 60: second covering member, 80: module substrate, 100: light emitting device, 101: base, 101a: first phosphor particle, 101b: first ceramic, 102a: second phosphor particle, 102b: second ceramic, 10 2c: third phosphor particles, 103: third ceramic, 104: fourth ceramic, 200: light emitting module, 300: light source device, 310: light source, 320: condenser lens, 330: phosphor wheel, 332: first substrate, 334: second substrate, 340: light receiving lens, 350: drive motor, 352: drive shaft, 360: filter, 362: filter, 400: projector, 470: DMD element, 480: projection lens, 490: screen, L1: distance between adjacent submount substrates, L2: distance between adjacent light transmitting members

Claims

1. a light-transmitting base made of an inorganic material containing first phosphor particles; second phosphor particles disposed on the substrate; a second ceramic having a light-transmitting property that fixes the second phosphor particles to the base, The molded body has a surface on which irregularities are formed due to the second phosphor particles, in a plan view, in a region where the second phosphor particles are arranged on the surface of the base and are present intermittently in a horizontal direction along the surface of the base, there are a portion where the second phosphor particles are present and a portion where the second phosphor particles are not present and the second ceramic is present, A molded body, in which, in a plan view, a total surface area on which the second phosphor particles are present is 50% or more and 97% or less when a unit area of ​​the surface of the base is taken as 100%.

2. The molded body according to claim 1 , wherein the substrate further comprises at least one of a first ceramic and glass.

3. The molded body according to claim 2 , wherein the first ceramic is at least one selected from the group consisting of aluminum oxide, aluminum nitride, mullite, and silicon nitride.

4. The molded body according to claim 1 , further comprising a third light-transmitting ceramic fixed onto the second phosphor particles.

5. The molded body according to claim 1 , wherein the second phosphor particles and the second ceramic have a maximum height within a range of 1 μm to 150 μm.

6. The molded body according to claim 1 , further comprising third phosphor particles fixed by the second ceramic in a horizontal direction along the surface of the base, the third phosphor particles emitting light in a different wavelength range than the second phosphor particles.

7. The molded body according to claim 6 , wherein the third phosphor particles convert the wavelength of light from an excitation light source.

8. the first phosphor particles have an emission peak wavelength in the range of 530 nm or more and 590 nm or less; The molded body according to claim 1 , wherein the second phosphor particles have an emission peak wavelength in the range of 600 nm or more and 670 nm or less.

9. the first phosphor particles are at least one aluminate phosphor; The molded body according to any one of claims 1 to 8, wherein the second phosphor particles are at least one selected from the group consisting of a fluoride phosphor, an alkaline earth metal silicon nitride phosphor, and an α-sialon phosphor.

10. The molded body according to claim 6 or any one of claims 7 to 9, which cites claim 6, wherein the third phosphor particles are at least one type of aluminate phosphor having an emission peak wavelength in the range of 530 nm to 590 nm.

11. the first phosphor particles have an emission peak wavelength in the range of 490 nm or more and 555 nm or less; The molded body according to claim 1 , wherein the second phosphor particles have an emission peak wavelength in the range of 600 nm or more and 690 nm or less.

12. 11. The molded body according to claim 4, further comprising a fourth light-transmitting ceramic fixed onto the second phosphor particles.

13. The molded body according to claim 1 , wherein the second ceramic is silicon dioxide.

14. The molded body according to claim 4 or any one of claims 5 to 13 which depends on claim 4, wherein the third ceramic is silicon dioxide.

15. The molded body according to claim 12, or claim 13 or claim 14 which derives from claim 12, wherein the fourth ceramic is aluminum oxide.

16. A light emitting device comprising a molded body described in any one of claims 1 to 15 and an excitation light source.

17. The light emitting device according to claim 16 , wherein the excitation light source is a semiconductor laser.

18. 18. The light emitting device according to claim 16, having a general color rendering index Ra of 70 or more.

19. preparing a light-transmitting base made of an inorganic material containing first phosphor particles; preparing a phosphor-containing composition including second phosphor particles and a second inorganic binder including polysilanol or polysilazane, the second phosphor particles being included in an amount within a range of 20% by mass to 90% by mass with respect to a total amount of the phosphor-containing composition; applying the phosphor-containing composition to the substrate to a thickness in the range of 20 μm to 150 μm; and performing a first heat treatment on the base and the phosphor-containing composition to fix the second phosphor particles to a surface of the base via a translucent second ceramic derived from the second inorganic binder, thereby obtaining a molded body in which unevenness caused by the second phosphor particles is formed on the surface, and in which, in a planar view, the surface of the base has parts where the second phosphor particles are present and parts where the second phosphor particles are not present and the second ceramic is present.

20. 20. The method for producing a molded body according to claim 19, wherein the total surface area of ​​the obtained molded body on which the second phosphor particles are present is 50% or more and 97% or less when the unit area of ​​the surface of the base is taken as 100% in a plan view.

21. The method for producing a molded body according to claim 19 or 20, wherein in the step of preparing the phosphor-containing composition, the second phosphor particles have an average particle size in the range of 12.5 μm or more and 50 μm or less.

22. 22. The method for producing a molded body according to claim 19, wherein in the step of preparing the phosphor-containing composition, the content of the second phosphor particles is in the range of 55% by mass or more and 90% by mass or less with respect to 100% by mass of a total amount of the phosphor-containing composition.

23. In the step of preparing the phosphor-containing composition, the second phosphor particles contain at least one phosphor selected from the group consisting of a fluoride phosphor and an alkaline earth metal silicon nitride phosphor; The method for producing a molded body according to any one of claims 19 to 22, wherein in the step of obtaining the molded body, a temperature of the first heat treatment is within a range of 150°C or more and 350°C or less.

24. 24. The method for producing a molded body according to claim 19, wherein in the step of preparing the base, the base further includes at least one of a first ceramic and glass.

25. After the step of obtaining the molded body, applying a third inorganic binder onto the second phosphor particles by a spin coating method; 25. The method for producing a molded body according to claim 19, further comprising: subjecting the third inorganic binder to a second heat treatment to fix the second phosphor particles via a translucent third ceramic derived from the third inorganic binder.

26. The method for producing a molded body according to claim 25, further comprising: fixing the second phosphor particles via the third ceramic, and then fixing a translucent fourth ceramic by an atomic layer deposition method.

27. 27. The method for producing a molded body according to claim 25 or 26, wherein the base comprises the first phosphor particles and the inorganic material obtained by curing or firing a first inorganic binder containing the first phosphor particles, and at least one of the first inorganic binder, the second inorganic binder, and the third inorganic binder comprises a ceramic precursor, and the ceramic precursor is at least one type of silica precursor selected from polysilanols and polysilazanes.

28. 28. The method for producing a molded body according to claim 27, wherein in the step of preparing the phosphor-containing composition, when the phosphor-containing composition is taken as 100 mass%, a content of the ceramic precursor in the phosphor-containing composition is in the range of 0.5 mass% or more and 70 mass% or less.

29. 29. The method for producing a molded body according to claim 19, wherein in the step of preparing the phosphor-containing composition, the phosphor-containing composition further contains third phosphor particles that emit light in a wavelength range different from that of the second phosphor particles.

30. 30. The method for producing a molded body according to claim 19, wherein in the step of applying the phosphor-containing composition to the base, the phosphor-containing composition is applied to the base by spraying, potting, or printing.

31. The method for producing a molded body according to claim 25 or any one of claims 26 to 30 which cites claim 25, wherein the temperature of the second heat treatment is within a range of 150°C or more and 350°C or less.

Images