Reflector cured product

Abstract

To provide a reflector cured product which is excellent in reflection efficiency of visible light and suppression in discoloration.SOLUTION: A reflector cured product is obtained by curing a resin composition containing a resin component containing a curable resin as a main component and a white inorganic filler. When a reflection electronic image obtained by imaging the surface of the reflector cured product with a scanning type electron microscope is observed, and the surface is classified into a first phase composed of the resin component and a second phase composed of the white inorganic filler, an average diameter of the second phase is 0.13 μm or more and 0.3 μm or less; in the second phase, a ratio of an aggregation phase composed of secondary particles of the white inorganic filler is 25% or less; and an occupied area ratio of the second phase is 10 area% or more and 50 area% or less with respect to 100 area% of the total of the first phase and the second phase. The aggregation phase is a phase composed of aggregation of two or more white inorganic filler fine particles, in the reflection electronic image.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a cured reflector. [Background technology]

[0002] In recent years, optical semiconductor elements such as LEDs (light-emitting diodes) have been widely used as indicators or light sources, not only for their high-efficiency light emission but also for their excellent driving and repetitive lighting characteristics. Therefore, optical semiconductor elements are widely used as indicators or light sources. In particular, white LEDs are widely used as backlights for display devices or camera flashes, and are also expected to be used as next-generation lighting devices. Such lighting devices are provided with a reflective material that reflects the emitted visible light to improve the efficiency of visible light extraction in the direction of irradiation. Furthermore, as white LEDs become smaller and lighter, high reflectivity in thin films is required. Currently, compositions containing a photocurable or thermosetting resin, such as an acrylic resin or an epoxy resin, in combination with a white inorganic filler are widely used as materials for reflective materials (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-140207 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the reflective material described in Patent Document 1, in order to increase the reflection efficiency of visible light, it was necessary to use a large amount of white inorganic filler in combination or to make the cured film thicker. As a result, problems such as peeling of the coating film or a decrease in mechanical strength, problems with dimensional accuracy in microfabrication due to the thick cured film, and problems with weight reduction and miniaturization occurred, making it difficult to apply the reflective material described in Patent Document 1 to recent high-output light-emitting devices.

[0005] An object of the present invention is to provide a cured reflective material that has excellent visible light reflection efficiency and excellent discoloration prevention properties. [Means for solving the problem]

[0006] According to the present invention, there is provided the following cured reflective material. [1] A cured reflector obtained by curing a resin composition containing a resin component mainly composed of a curable resin and a white inorganic filler, When a backscattered electron image obtained by imaging the surface of the cured reflector material with a scanning electron microscope is observed and the result is classified into a first phase consisting of the resin component and a second phase consisting of the white inorganic filler, The average diameter of the second phase is 0.13 μm or more and 0.3 μm or less, the ratio of an aggregate phase consisting of secondary particles of the white inorganic filler in the second phase is 25% or less; the occupied area ratio of the second phase is 10 area % or more and 50 area % or less with respect to 100 area % in total of the first phase and the second phase, The aggregated phase is a phase consisting of two or more aggregated white inorganic filler particles in the backscattered electron image, The ratio of the aggregation phase is obtained by setting a rectangular measurement field of view of 4.5 μm×6.0 μm in the backscattered electron image, observing all second phases in the measurement field, and classifying them into the aggregation phases and single particle phases other than the aggregation phases, and then calculating the ratio of the number of the aggregation phases to the number of all second phases. Cured reflective material. [2] In the cured reflector according to [1], The white inorganic filler contains at least one metal oxide selected from the group consisting of titania, zirconia, yttria-stabilized zirconia, alumina, and silica. Cured reflective material. [3] In the cured reflector according to [1] or [2], the white inorganic filler is a core-shell type filler having a core layer and a shell layer, the core layer is made of titania, The shell layer is made of at least one metal oxide selected from the group consisting of zirconia, alumina, and silica. Cured reflective material. [4] In the cured reflector according to any one of [1] to [3], The white inorganic filler has been subjected to an organic surface treatment. Cured reflective material. [5] In any of the cured reflective materials [1] to [4], When the thickness of the cured reflective material is 30 μm, The reflectance of the cured reflective material at a wavelength of 450 nm is 92% or more in the SCI (Specular Component Include) method, After reflow treatment in a nitrogen atmosphere (oxygen concentration: 2000 ppm) at a peak temperature of 260°C or higher for 6 seconds and at a melting temperature of 240°C or higher for 60 seconds, the reflectance of the cured reflective material at a wavelength of 450 nm is 91.5% or higher according to the SCI method. Cured reflective material. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to provide a cured reflective material that has excellent visible light reflection efficiency and excellent discoloration suppression. [Brief explanation of the drawings]

[0008] [Figure 1] 1 shows backscattered electron images obtained by photographing the surfaces of the cured reflectors obtained in Example 1 and Comparative Example 1 with a scanning electron microscope. [Figure 2] 1 is a graph showing the relationship between the number of particles constituting the second phase and the ratio thereof in the cured reflector materials obtained in Example 1 and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0009] The cured reflector according to this embodiment is a cured reflector obtained by curing a resin composition containing a resin component whose main component is a curable resin and a white inorganic filler. When the surface of this cured reflector is photographed with a scanning electron microscope to obtain a backscattered electron image and classified into a first phase consisting of the resin component and a second phase consisting of the white inorganic filler, the average diameter of the second phase is 0.13 μm or more and 0.3 μm or less, the proportion of an aggregate phase consisting of secondary particles of the white inorganic filler in the second phase is 25% or less, and the area ratio of the second phase is 10% or more and 50% or less based on a total area of ​​the first phase and the second phase (100%).

[0010] The average diameter of the second phase must be 0.13 μm or more and 0.3 μm or less. If the average diameter of the second phase is outside this range, the reflection efficiency of visible light becomes insufficient. From the same viewpoint, the average diameter of the second phase is preferably 0.16 μm or more and 0.25 μm or less. The average diameter of the second phase can be adjusted to fall within the above range by the following methods: For example, the average diameter of the second phase can be adjusted by changing the average particle diameter of the white inorganic filler.

[0011] The ratio of the aggregated phase consisting of secondary particles of the white inorganic filler in the second phase must be 25% or less. If the ratio of the aggregated phase exceeds the upper limit, the reflection efficiency of visible light becomes insufficient and discoloration suppression becomes insufficient. From the same viewpoint, the ratio of the aggregated phase is preferably 1% or more and 20% or less, more preferably 2% or more and 15% or less, and particularly preferably 3% or more and 12% or less. Furthermore, from the viewpoint of visible light reflection efficiency and discoloration suppression, the average number of white inorganic fillers constituting the second phase (hereinafter also referred to as the average number of aggregated particles) is preferably 1.3 or less, more preferably 1.2 or less. The following methods can be used to adjust the ratio of the aggregated phase or the average number of aggregated particles to fall within the above range: For example, the ratio of the aggregated phase or the average number of aggregated particles can be adjusted by changing the type of resin component, the type of white inorganic filler, the surface treatment, and the dispersion method.

[0012] The area ratio of the second phase must be 10 area % or more and 50 area % or less, relative to 100 area % of the total of the first phase and the second phase. If the area ratio of the second phase is less than the lower limit, the reflection efficiency of visible light becomes insufficient. On the other hand, if the area ratio of the second phase exceeds the upper limit, the cured reflector becomes prone to peeling. From the same viewpoint, the area ratio of the second phase is preferably 20 area % or more and 40 area % or less, relative to 100 area % of the total of the first phase and the second phase. The method for adjusting the area ratio of the second phase to fall within the above range includes the following: For example, the area ratio of the second phase can be adjusted by changing the blending amount of the white inorganic filler.

[0013] In this embodiment, the backscattered electron image, the ratio of the aggregated phase, and the average number of aggregated particles are obtained as follows. The backscattered electron image is obtained by imaging the surface of the cured reflector with a scanning electron microscope. Any known scanning electron microscope can be used as appropriate. The backscattered electron image may be subjected to binarization processing in order to calculate the average diameter of the second phase, the proportion of the aggregated phase, and the occupied area ratio. The binarization processing can be performed, for example, using an image analysis and measurement system (product name "WinROOF2021", manufactured by Mitani Shoji Co., Ltd.). The aggregate phase is a phase consisting of two or more aggregated white inorganic filler particles in a backscattered electron image, whereas a phase consisting of a single white inorganic filler particle is a single particle phase. The ratio of the aggregate phase is obtained by setting a rectangular measurement field of 4.5 μm × 6.0 μm in the backscattered electron image, observing all second phases in this measurement field, and classifying them into aggregate phases and single particle phases, and then calculating the ratio of the number of aggregate phases to the number of all second phases (the sum of the number of single particle phases and the number of aggregate phases) ((number of aggregate phases / number of all second phases) × 100 (%)). The average number of agglomerated particles can be obtained by setting a rectangular measurement field of view of 4.5 μm × 6.0 μm in a backscattered electron image, observing all the second phases in this measurement field, counting the number of white inorganic fillers constituting the second phases, and calculating the average value.

[0014] (Resin composition) The resin composition used in this embodiment contains a resin component and a white inorganic filler. For example, this resin composition is applied to form a coating film, and then cured to obtain a cured reflective material. Curing conditions can be appropriately set depending on the type of resin component.

[0015] (resin component) The resin component (solid content) used in this embodiment is mainly composed of a curable resin, which can be cured to obtain a cured reflective material. The curable resin is a resin that has at least one of photocurability and thermosetting properties, and may be a resin that has both photocurability and thermosetting properties.

[0016] Examples of the curable resin include epoxy resin, phenol resin, urethane resin, and melamine resin. The curable resin may be, for example, a resin having a carboxyl group and a photosensitive group. The carboxyl group reacts with an epoxy compound to have thermosetting properties. Examples of such curable resins include (i) a resin obtained by partially reacting an epoxy group-containing unsaturated compound with a copolymer of an unsaturated carboxylic acid and a compound other than the unsaturated carboxylic acid that has an unsaturated double bond, and (ii) a resin obtained by addition-reacting a carboxyl group-containing compound with the epoxy groups of a copolymer of an epoxy group-containing unsaturated compound and a compound other than the epoxy group-containing unsaturated compound that has an unsaturated double bond, and then reacting the resulting hydroxyl groups with a saturated or unsaturated polybasic acid anhydride.

[0017] Examples of the unsaturated carboxylic acid used in the synthesis of the curable resin (i) include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, and vinylacetic acid. Among these, acrylic acid or methacrylic acid is preferred, and methacrylic acid is particularly preferred. Furthermore, examples of compounds having an unsaturated double bond other than unsaturated carboxylic acids include methyl methacrylate, methyl acrylate, ethyl methacrylate, cyclohexyl methacrylate, phenoxymethyl methacrylate, and 2-hydroxyethyl methacrylate. Examples of the epoxy group-containing unsaturated compound include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, and 4-hydroxybutyl acrylate glycidyl ether.

[0018] Examples of the epoxy group-containing unsaturated compound used in the synthesis of the curable resin (ii) include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, and 4-hydroxybutyl acrylate glycidyl ether. Furthermore, examples of compounds having an unsaturated double bond other than the epoxy group-containing unsaturated compound include methyl methacrylate, methyl acrylate, ethyl methacrylate, cyclohexyl methacrylate, phenoxymethyl methacrylate, and 2-hydroxyethyl methacrylate. Examples of the carboxyl group-containing compound include acrylic acid and methacrylic acid. Furthermore, examples of the saturated or unsaturated polybasic acid anhydride include acid anhydrides of succinic acid, maleic acid, adipic acid, citric acid, phthalic acid, and tetrahydrophthalic acid.

[0019] The resin component used in this embodiment may contain an epoxy compound. The epoxy compound is a compound having an epoxy group. The epoxy compound can increase the crosslink density of the cured product of the resin composition. As the epoxy compound, any known epoxy compound can be used.

[0020] The resin component used in this embodiment may contain a photopolymerization initiator, which can improve the photosensitivity of the resin composition. As the photopolymerization initiator, any known photopolymerization initiator can be used.

[0021] The resin component used in this embodiment may contain a reactive diluent. The reactive diluent is, for example, a photopolymerizable monomer, which is a compound having at least one polymerizable double bond per molecule. The reactive diluent can improve the photocurability of the resin composition. As the reactive diluent, any known diluent can be used as appropriate.

[0022] (white inorganic filler) The white inorganic filler used in this embodiment is a white inorganic filler that can impart visible light reflectivity to the cured reflective material. Examples of the white inorganic filler include titania, zirconia, yttria-stabilized zirconia, alumina, and silica. These may be used alone or in combination of two or more.

[0023] From the viewpoint of dispersibility of the white inorganic filler in the resin component, the white inorganic filler is preferably a core-shell type filler having a core layer and a shell layer. Here, the core layer is preferably made of titania. Furthermore, the shell layer is preferably made of at least one metal oxide selected from the group consisting of zirconia, alumina, and silica. In addition, from the viewpoint of further improving the dispersibility of the white inorganic filler, it is preferable that the white inorganic filler has been subjected to an organic surface treatment. The organic surface treatment may be a surface treatment using a silane coupling agent or the like.

[0024] (Other ingredients) The resin composition used in this embodiment may contain other components as needed in addition to the resin component and the white inorganic filler. Other components include antifoaming agents, thickeners, thixotropic agents, flame retardants, curing catalysts, and non-reactive diluents. These may be used alone or in combination of two or more.

[0025] (Method of producing resin composition) The method for producing the resin composition used in this embodiment is not limited to a specific method as long as it can ensure the dispersibility of the white inorganic filler. For example, the resin composition can be produced by blending the components in a predetermined ratio and then kneading or mixing them at room temperature using a kneading device such as a three-roll mill, a ball mill, or a sand mill, or a stirring device such as a super mixer or a planetary mixer. Among these, the use of a three-roll mill is preferred. Furthermore, pre-kneading or pre-mixing may be performed as necessary before kneading or mixing.

[0026] (Method for producing cured reflective material) The cured reflective material according to this embodiment can be produced by forming a cured reflective material on a substrate using the resin composition used in this embodiment described above. The substrate may be an LED substrate or the like.

[0027] Specifically, first, the resin composition used in this embodiment is applied onto a substrate, and then pre-dried to form a coating film. Examples of methods for applying the coating include screen printing, bar coating, applicator, blade coating, knife coating, roll coating, gravure coating, and spray coating. The conditions for pre-drying vary depending on the type of resin composition and are not particularly limited, but may be, for example, heating at a temperature in the range of 60° C. to 80° C. for 15 minutes to 60 minutes. By such pre-drying, the solvent in the resin composition can be evaporated, and a tack-free coating film can be formed. The thickness of the coating film (dry film thickness) is not particularly limited, but is usually from 5 μm to 200 μm, and preferably from 10 μm to 70 μm.

[0028] When a photodevelopable resin composition is used as the resin composition, a negative film having a pattern in which the areas other than the lands of the circuit pattern are transparent may be adhered to the coating film, and the coating film after exposure may be developed by irradiating it with ultraviolet light from above and then removing the unexposed areas with a dilute alkaline aqueous solution, thereby forming openings in the coating film corresponding to the circuit pattern.

[0029] Next, the substrate is subjected to a heat treatment (hereinafter sometimes referred to as post-cure), which allows a cured reflective material to be formed on the substrate. The heat treatment conditions vary depending on the type of resin composition and are not particularly limited. For example, a hot air circulation dryer or a far-infrared oven can be used as the heat treatment oven. When a hot air circulation dryer is used, the heat treatment temperature is preferably 130°C or higher and 170°C or lower, and the heat treatment time is preferably 30 minutes or higher and 120 minutes or lower. When a far-infrared oven is used, the heat treatment temperature is preferably 200°C or higher and 250°C or lower, and the heat treatment time is preferably 3 minutes or higher and 10 minutes or lower.

[0030] (Physical properties of cured reflective material) As described above, the cured reflective material according to this embodiment has excellent visible light reflection efficiency and excellent discoloration suppression. Furthermore, compared with conventional reflective materials, the cured reflective material according to this embodiment can maintain sufficient reflection efficiency even when the thickness of the cured reflective material is reduced. Therefore, while the thickness of conventional cured reflective materials is usually 100 μm or more and 500 μm or less, the cured reflective material according to this embodiment can be made thinner than conventional ones. The cured reflector according to this embodiment preferably has a thickness of 5 μm or more and 200 μm or less, more preferably 10 μm or more and 100 μm or less, and particularly preferably 20 μm or more and 70 μm or less.

[0031] The cured reflective material according to this embodiment preferably satisfies the following conditions when the thickness of the cured reflective material is 30 μm. The reflectance of the cured reflective material at a wavelength of 450 nm is preferably 92% or more in the SCI (Specular Component Include) method. If this reflectance is equal to or higher than the lower limit, it can be said that the reflective material has excellent visible light reflection efficiency. Furthermore, after reflow treatment in a nitrogen atmosphere (oxygen concentration: 2000 ppm) under conditions of a peak temperature of 260°C or higher for 6 seconds and a melting temperature of 240°C or higher for 60 seconds, the reflectance of the cured reflective material at a wavelength of 450 nm is preferably 91.5% or higher according to the SCI method. If this reflectance is equal to or higher than the lower limit mentioned above, it can be determined that a decrease in reflection efficiency due to a heat treatment such as reflow treatment has been suppressed. [Example]

[0032] Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples in any way.

[0033] (resin component) Curable resin: A mixture containing acrylate copolymer resin (manufactured by Tamura Corporation), an epoxy compound, and a reactive diluent (white inorganic filler) White inorganic filler A: Titanium oxide (silica-alumina-siloxane treated), product name "PF-728", manufactured by Ishihara Sangyo Kaisha White inorganic filler B: Titanium oxide (silica-alumina treated), product name "PF-726", manufactured by Ishihara Sangyo Kaisha (Other ingredients) Thickener: Hydrophilic fumed silica, product name "Reolosil DM-20S", manufactured by Tokuyama Corporation Antifoaming agent: Silicone-based antifoaming agent, product name "X-50-1095C", manufactured by Shin-Etsu Chemical Co., Ltd.

[0034] [Example 1] 56.8% by mass of curable resin, 39.7% by mass of white inorganic filler A, 1.6% by mass of thickener, and 1.9% by mass of antifoaming agent were placed in a container and premixed with a stirrer, and then mixed and dispersed at room temperature using a three-roll mill to obtain a resin composition. Then, a copper foil solid substrate (copper foil thickness: 35 μm, substrate thickness: 1.6 mm) was surface treated by buffing, and the obtained resin composition was then applied by screen printing to a predetermined dry film thickness to obtain a coated substrate. After application, the substrate was pre-dried in a box furnace at 80°C for 20 minutes. After pre-drying, the substrate was post-cured in a box furnace at 150°C for 60 minutes to form a cured reflective material on the substrate, thereby producing a substrate for evaluation. Three evaluation substrates were produced, each with a different thickness of the cured reflective material: 20 μm, 45 μm, and 70 μm.

[0035] [Comparative Example 1] A resin composition and a substrate for evaluation were obtained in the same manner as in Example 1, except that the materials were mixed according to the formulation shown in Table 1.

[0036] [Evaluation of cured reflective material] The cured reflective material was evaluated (observation of backscattered electron images, reflectance, reflectance after reflow treatment, b-value retention, and 95% reflection equivalent film thickness) using the following methods. The results are shown in Table 1. (1) Observation of backscattered electron images Using an evaluation substrate with a thickness of 20 μm of the cured reflector as a sample, the coating surface was imaged at 20,000 times magnification using a scanning electron microscope. The resulting 4.5 μm x 6.0 μm backscattered electron image was then analyzed using an image analysis and measurement system (product name "WinROOF2021" manufactured by Mitani Shoji Co., Ltd.) to extract the second phase and perform binarization. The resulting backscattered electron image is shown in Figure 1. Furthermore, the average diameter of the second phase, the proportion of aggregated phases, the average number of aggregated particles, and the area ratio of the second phase were calculated from the backscattered electron image. Furthermore, the relationship between the number of particles constituting the second phase and their proportion is shown in Figure 2. (2)Reflectance For three evaluation substrates with different thicknesses of the cured reflective material, the SCI at 450 nm was measured using a spectrophotometer (product name "CM-700d", manufactured by Konica Minolta, Inc.) The obtained reflectance values ​​were plotted, and the reflectance converted to a thickness of 30 μm was calculated from the approximation curve. (3) Reflectance after reflow treatment Three evaluation substrates with different thicknesses of the cured reflective material were each subjected to a reflow treatment in a nitrogen atmosphere (oxygen concentration: 2000 ppm) at a peak temperature of 260°C or higher for 6 seconds and a melting temperature of 240°C or higher for 60 seconds. After the reflow treatment, the SCI at 450 nm of each evaluation substrate was measured using a spectrophotometer (product name "CM-700d" manufactured by Konica Minolta). The resulting reflectance values ​​were plotted, and the reflectance converted to a thickness of 30 μm was calculated from the approximation curve. (4) b-value retention rate For three evaluation substrates with different thicknesses of the cured reflector material, the b value was measured using a spectrophotometer (product name "CM-700d", manufactured by Konica Minolta) in accordance with JIS Z 8781-4 "Colorimetry - Part 4: CIE1976 L*a*b* color space." The obtained b values ​​were plotted, and the b value converted to a thickness of 30 μm (initial b value) was calculated from the approximation curve. Next, three evaluation substrates with different thicknesses of the cured reflective material were each subjected to a reflow treatment in a nitrogen atmosphere (oxygen concentration: 2000 ppm) under conditions of a peak temperature of 260°C or higher for 6 seconds and a melting temperature of 240°C or higher for 60 seconds. For each of these evaluation substrates after reflow treatment, the b value converted to a thickness of 30 μm (b value after reflow treatment) was calculated in the same manner as above. Then, the b-value retention rate (unit: %) was calculated using the following formula: Note that the higher the b-value retention rate, the better the discoloration suppression. b-value retention rate = (b-value after reflow processing / initial b-value) x 100 (5) 95% reflection equivalent film thickness For three evaluation substrates with different thicknesses of the cured reflective material, the SCI at 450 nm was measured using a spectrophotometer (product name "CM-700d", manufactured by Konica Minolta, Inc.) The obtained reflectance values ​​were plotted, and the equivalent film thickness at which the reflectance at 450 nm became 95% was calculated from the approximation curve.

[0037] [Table 1]

[0038] As is clear from the results shown in Table 1, it was confirmed that the cured reflective material of the present invention (Example 1) was good in all of the results of reflectance, reflectance after reflow treatment, b-value retention, and 95% reflection equivalent film thickness. Therefore, it was confirmed that the cured reflective material of the present invention is excellent in visible light reflection efficiency and in discoloration suppression. [Industrial Applicability]

[0039] The cured reflector of the present invention is useful as a light-reflecting material, for example, a reflector for a light-emitting device, particularly a white LED.

Claims

1. A cured reflective material obtained by curing a resin composition containing a resin component mainly composed of a curable resin and a white inorganic filler, When a backscattered electron image obtained by imaging the surface of the cured reflector material with a scanning electron microscope is observed and the result is classified into a first phase consisting of the resin component and a second phase consisting of the white inorganic filler, The average diameter of the second phase is 0.13 μm or more and 0.3 μm or less, a ratio of an aggregate phase consisting of secondary particles of the white inorganic filler in the second phase is 25% or less; an occupied area ratio of the second phase is 10 area % or more and 50 area % or less with respect to 100 area % in total of the first phase and the second phase; The aggregated phase is a phase consisting of two or more aggregated white inorganic filler particles in the backscattered electron image, The ratio of the aggregation phase is obtained by setting a rectangular measurement field of view of 4.5 μm×6.0 μm in the backscattered electron image, observing all second phases in the measurement field, and classifying the second phases into the aggregation phases and single particle phases other than the aggregation phases, and then calculating the ratio of the number of the aggregation phases to the number of all second phases. Cured reflective material.

2. The cured reflective material according to claim 1, The white inorganic filler contains at least one metal oxide selected from the group consisting of titania, zirconia, yttria-stabilized zirconia, alumina, and silica. Cured reflective material.

3. The cured reflector according to claim 1 or 2, the white inorganic filler is a core-shell type filler having a core layer and a shell layer, the core layer is made of titania, The shell layer is made of at least one metal oxide selected from the group consisting of zirconia, alumina, and silica. Cured reflective material.

4. The cured reflector according to claim 1 or 2, The white inorganic filler has been subjected to an organic surface treatment. Cured reflective material.

5. The cured reflector according to claim 1 or 2, When the thickness of the cured reflective material is 30 μm, The reflectance of the cured reflective material at a wavelength of 450 nm is 92% or more in the SCI (Specular Component Include) method, The reflectance of the cured reflective material at a wavelength of 450 nm after reflow treatment under conditions of a peak temperature of 260°C or higher for 6 seconds and a melting temperature of 240°C or higher for 60 seconds in a nitrogen atmosphere (oxygen concentration: 2000 ppm) is 91.5% or higher according to the SCI method. Cured reflective material.

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