JP2009129947A - Reflector for optical semiconductor, and optical semiconductor device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reflector for an optical semiconductor which has superior resistance to ultraviolet rays, thermal resistance, and ultraviolet-rays reflectivity. <P>SOLUTION: The reflector for the optical semiconductor comprises a stack of a base made of a composition containing anatase type titanium dioxide and a reflective layer made of a composition containing components (1) and (2): (1) 40 to 80 mass% of a thermosetting compound and/or a photosetting compound, and (2) 20 to 60 mass% of hollow particles made of a material having a transmittance of ≥50% to ultraviolet ray of 350 nm in wavelength. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical semiconductor reflector and an optical semiconductor device using the same.

  Since the 1990s, the progress of light emitting diodes (LEDs) has been remarkable. Among these, white LEDs are expected as next-generation light sources that replace conventional white light bulbs, halogen lamps, HID lamps, and the like. In fact, LEDs have been evaluated for their features such as long life, power saving, temperature stability, low voltage drive, etc., and are applied to displays, destination display boards, in-vehicle lighting, signal lights, emergency lights, mobile phones, video cameras, and the like. Such a light emitting device is usually manufactured by fixing an LED to a concave reflecting layer formed by integrally molding a synthetic resin with a lead frame and sealing with a sealing material such as an epoxy resin or a silicone resin.

  Recently, LEDs that emit ultraviolet light having a wavelength of 380 nm to 400 nm have come to be used. In order to increase the brightness of such LEDs, a reflective layer that reflects ultraviolet rays with high efficiency is required, but many of the reflective layers used in current LEDs have extremely low ultraviolet reflectance, and improvements are desired. It was.

A resin composition obtained by adding titanium oxide to a polyamide-based resin (for example, Patent Document 1) is often used as an LED reflector. This material has a high reflectance in the visible light region. However, since titanium oxide absorbs ultraviolet rays having a wavelength of 400 nm or less, the material containing titanium oxide hardly reflects ultraviolet rays having a wavelength of 400 nm or less.
It is known that anatase-type titanium oxide has higher ultraviolet reflectivity than rutile-type titanium oxide. Therefore, it was found that when anatase-type titanium oxide was added to the polyamide-based resin, the reflectance with respect to ultraviolet rays was improved (about 60% at a wavelength of 380 nm), but when ultraviolet rays were irradiated for a long time, the reflectance was lowered. .

  Patent Document 2 discloses an optical semiconductor device including a resin layer containing a light reflective filler around a light emitting element. As the light reflective filler, compounds containing titanium and oxygen such as titanium oxide and potassium titanate are disclosed. Potassium titanate is mentioned as a particularly suitable light reflecting filler. When potassium titanate is used, the reflectance is as high as 85% at 400 nm, but the reflectance is about 70% at 380 nm, and it cannot be said that it has sufficient ultraviolet reflectance.

Patent Document 3 discloses an optical semiconductor device in which a composition in which hollow particles are mixed with a thermosetting resin or a photocurable compound is applied and cured on the surface of a molded body made of a resin composition containing rutile titanium oxide. is doing. The reflectivity of the reflector in the optical semiconductor device depends on the thickness of the hollow particle layer, and the reflectivity of the thin film was not sufficient. For example, when the thickness of the hollow particle layer is 300 μm, the reflectance at 380 nm is about 75% and the reflectance at 400 nm is slightly less than 80%, and further improvement in reflectance is necessary.
JP-A-2-288274 JP 2000-150969 A International Publication No. 07/037093 Pamphlet

  An object of this invention is to provide the reflector for optical semiconductors which has the outstanding ultraviolet resistance, heat resistance, and ultraviolet reflectivity.

As a result of intensive studies to solve the above problems, the present inventor has an excellent ultraviolet resistance with a laminate of a substrate comprising a composition containing anatase-type titanium oxide and a reflective layer comprising a composition containing hollow particles, It discovered that it had heat resistance and ultraviolet reflectivity, and completed this invention.
According to the present invention, the following reflectors for optical semiconductors and the like are provided.
1. The reflector for optical semiconductors which is a laminated body of the base | substrate which consists of a composition containing an anatase type titanium oxide, and the reflection layer which consists of a composition containing following component (1) and (2).
(1) Thermosetting compound and / or photocurable compound: 40 to 80% by mass
(2) Hollow particles made of a material having a transmittance of 50% or more for ultraviolet rays having a wavelength of 350 nm: 20 to 60% by mass
2. The reflector for optical semiconductors according to 1, wherein the thermosetting compound or the photocurable compound is a silicone compound, an epoxy compound, or a (meth) acrylic acid ester compound.
3. The reflector for optical semiconductors according to 1 or 2, wherein the hollow particles are a crosslinked resin or an inorganic compound.
4). The reflector for optical semiconductors according to any one of 1 to 3, wherein the hollow particles are a crosslinked styrene resin, a crosslinked acrylic resin, inorganic glass, or silica.
5). The reflector for optical semiconductors in any one of 1-4 whose composition containing the said anatase type titanium oxide contains crystalline polystyrene, a liquid crystal polymer, or a polyamide resin.
6). The reflector for optical semiconductors according to any one of 1 to 5, wherein the reflectance of the substrate with respect to ultraviolet rays having a wavelength of 400 nm is 60% or more.
An optical semiconductor device including the optical semiconductor reflector according to any one of 7.1 to 6.

  ADVANTAGE OF THE INVENTION According to this invention, the reflector for optical semiconductors which has the outstanding ultraviolet resistance, heat resistance, and ultraviolet reflectivity can be provided.

The reflector for optical semiconductors of the present invention is a laminate of a substrate made of a composition containing anatase-type titanium oxide and a reflective layer made of a composition containing the following components (1) and (2).
(1) Thermosetting compound and / or photocurable compound: 40 to 80% by mass
(2) Hollow particles made of a material having a transmittance of 50% or more for ultraviolet rays having a wavelength of 350 nm: 20 to 60% by mass

  The hollow particles reflect ultraviolet rays, but do not absorb but transmit. Anatase type titanium oxide has excellent ultraviolet reflectance. In the present invention, by making the reflective layer containing hollow particles and the substrate containing anatase-type titanium oxide into a laminate, the ultraviolet reflectance can be dramatically improved by the synergistic effect of both.

  Anatase-type titanium oxide is titanium oxide having an anatase-type crystal structure, and is preferably titanium oxide used as a white pigment. Commercially available products such as A220 manufactured by Ishihara Sangyo Co., Ltd., A197, A950, and FTA manufactured by Sakai Chemical Industry Co., Ltd. can be used as the anatase type titanium oxide.

  In the composition constituting the substrate, the content of anatase-type titanium oxide is usually 5 to 50% by mass, preferably 8 to 40% by mass. When the content of the anatase type titanium oxide is less than 5% by mass, the reflectance of the obtained substrate with respect to ultraviolet rays having a wavelength of 400 nm may be less than 60%. On the other hand, when the content of the anatase-type titanium oxide exceeds 50% by mass, the mechanical properties of the obtained substrate may be deteriorated.

Resin (hereinafter sometimes referred to as matrix resin) contained in the composition constituting the substrate includes heat resistance such as crystalline polystyrene, liquid crystal polymer, polyamide resin, polyester resin, polyether resin, and polyether ketone resin. Resins are included, and are preferably crystalline polystyrene, liquid crystal polymer, and polyamide resin because of less light absorption, and more preferably crystalline polystyrene, particularly preferably syndiotactic polystyrene because of less color change due to heat. is there.
A resin obtained by mixing one or more of the above resins can be used as a matrix resin.

The composition constituting the substrate may contain 5 to 50% by mass, preferably 10 to 40% by mass, of an inorganic compound having an aspect ratio of 10 or more. By including the inorganic compound, the linear expansion coefficient of the substrate can be lowered, and the reliability of the optical semiconductor device can be increased.
When the content of the inorganic compound is less than 5% by mass, the linear expansion coefficient of the substrate may increase. On the other hand, if the content of the inorganic compound exceeds 50% by mass, the moldability of the substrate may be lowered.

  Examples of the inorganic compound having an aspect ratio of 10 or more include glass fiber, potassium titanate whisker, silicon carbide whisker, aluminum borate whisker, calcium carbonate whisker, and nanoclay, and preferably glass fiber, potassium titanate whisker, or nanoclay. Is used.

  In addition, the composition constituting the substrate is not limited to the effects of the present invention, and various known additions such as a crystal nucleating agent, an antioxidant, a light stabilizer, a lubricant, a plasticizer, an antistatic agent, and a release agent. An agent, a thermoplastic resin, a compatibilizing agent and the like may be included.

  Examples of thermoplastic resins include polyolefins such as polyethylene, polypropylene, and polypentene; polythioethers such as polyphenylene sulfide; polycarbonate, polyimide, polyamideimide, polymethyl methacrylate, ethylene-acrylic acid copolymer, acrylonitrile-styrene copolymer, and acrylonitrile. -Chlorinated polyethylene-styrene copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, acrylonitrile-butadiene-styrene copolymer, vinyl chloride resin, chlorinated polyethylene, fluorinated polyethylene, polyacetal, heat Plastic polyurethane elastomer, polybutadiene, styrene elastomer (SBR, SBS, SEBS, SEPS, etc.), styrene-maleic anhydride copolymer, etc. It is.

  As a compatibilizing agent, a modified product of a polyphenylene ether polymer can be used. For example, maleic anhydride, maleic acid, fumaric acid, maleimide, maleic hydrazide; poly (2,6-dimethylenephenylene-1,4-ether) introduced with amino group, carboxylic acid group, hydroxyl group, epoxy group, etc. Can be used.

  The composition constituting the substrate may consist essentially of anatase-type titanium oxide and a matrix resin, or may consist solely of these components. “Substantially” means that the composition constituting the substrate consists only of anatase-type titanium oxide and a matrix resin, and can contain the following additives in addition to these components.

  The substrate is prepared by mixing a composition containing anatase-type titanium oxide and the above additives at a predetermined ratio, and kneading the obtained mixture using a Banbury mixer, a single screw extruder, a twin screw extruder or the like, It can be produced by using a known molding method.

Any of a monomer, an oligomer, and a polymer may be sufficient as the thermosetting compound and photocurable compound contained in the composition which comprises a reflection layer.
As said thermosetting compound and photocurable compound, the silicone type compound, (meth) acrylic acid ester type compound, and epoxy type compound which give a high heat resistant polymer are preferable. Among these, silicone compounds and (meth) acrylic acid ester compounds are more preferable because they give a polymer excellent in ultraviolet resistance.

  Commercially available products such as KER2500A / B and SCR1100A / B manufactured by Shin-Etsu Chemical Co., Ltd., XJL-0012A / B and XJL-0016A / B manufactured by Nippon Pernox Co., Ltd. can be used as the silicone compound.

  As the (meth) acrylic acid ester compound, an alicyclic hydrocarbon group-containing (meth) acrylic acid ester compound having 7 or more carbon atoms is preferable because it gives a polymer excellent in heat-resistant yellowing. Examples of the alicyclic hydrocarbon group having 7 or more carbon atoms include an adamantyl group, a norbornyl group, and a dicyclopentanyl group. Moreover, you may use it, mixing a C7 or more alicyclic hydrocarbon group containing (meth) acrylic ester compound and other (meth) acrylic ester.

  The composition constituting the reflective layer includes hollow particles. When the material of the hollow particles has a thickness of 250 μm, the transmittance with respect to ultraviolet rays having a wavelength of 350 nm is 50% or more, and preferably 60% to 100%.

  Since the ultraviolet rays that have passed through the outer shell of the hollow particles are reflected by the hollow portion, a material having a high ultraviolet transmittance is required. In order to increase the reflectance at the hollow portion, it is preferable that the difference in refractive index between the portion constituting the hollow particle and the gas existing inside the hollow particle is large. The gas present inside the hollow particles is usually air, but may be an inert gas such as nitrogen or argon, or may be a vacuum.

  The hollow particles are preferably particles that contain one or more closed cells inside the particles, but may be secondary particles in which hollow portions are formed. The material constituting the hollow particles may be an organic compound or an inorganic compound. However, when light is absorbed by the outer shell of the hollow particles, the ultraviolet rays that reach the inside of the hollow particles are reduced, and the reflectance at the hollow portion is reduced. Therefore, those that do not absorb much ultraviolet rays are preferable. Moreover, since a hollow part is destroyed by heat processing and a reflective characteristic will be lost when a hollow part is lose | eliminated, a thing with high heat resistance is preferable.

As a material for the hollow particles, an inorganic compound or a crosslinked resin is preferably used.
Examples of the inorganic compound include inorganic glass, metal oxides such as silica and alumina, and metal salts such as calcium carbonate, barium carbonate, calcium silicate, and nickel carbonate. Preferably, inorganic glass or silica is used.
As said crosslinked resin, a styrene resin, an acrylic resin, these crosslinked bodies, etc. can be used suitably, These may be included 1 type or 2 or more types. Preferably, a crosslinked styrene resin or a crosslinked acrylic resin is used.

  The outer diameter of the hollow particles is not particularly limited. From the viewpoint of light reflectivity and handleability, 0.01 to 500 μm is preferable. When the outer diameter of the hollow particles is less than 0.01 μm, the viscosity before curing of the composition containing the heat or photocurable compound and the hollow particles becomes high, and there is a possibility that shaping is difficult. On the other hand, when the outer diameter of the hollow particles is more than 500 μm, the surface of the reflective layer is roughened and the reflectance may be lowered. The inner diameter of the hollow particles is not particularly limited. From the viewpoint of light reflectivity, the inner diameter of the hollow particles is preferably 0.005 to 100 μm, more preferably 0.1 to 50 μm.

  Content of the hollow particle contained in the composition which comprises a reflection layer is 20-60 mass%, Preferably it is 25-55 mass%. When content of a hollow particle is less than 20 mass%, there exists a possibility that the reflectance of the reflector obtained may fall. On the other hand, when the content of the hollow particles is more than 60% by mass, the viscosity of the composition constituting the reflective layer before polymerization may be increased, and shaping may be difficult.

  The composition constituting the reflective layer may consist essentially of a thermosetting compound and / or a photocurable compound and hollow particles, or may consist only of these components. “Substantially” means that the composition constituting the reflective layer is composed only of a thermosetting compound and / or a photocurable compound and hollow particles, and may contain the following additives in addition to these components. It is.

Moreover, the composition which comprises a reflection layer may also contain a well-known antioxidant, a light stabilizer, etc. as an additive in the range which does not impair the effect of this invention.
Examples of the antioxidant include phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, lactone antioxidants, amine antioxidants, and the like. The content of these antioxidants is usually 0.005 to 5 parts by mass, preferably 0.02 to 100 parts by mass of the resin component (thermosetting compound and photocurable compound) contained in the composition. 2 parts by mass. Two or more of these antioxidants may be used in combination.

  As the light stabilizer, a hindered amine light stabilizer can be suitably used. Content of a light stabilizer is 0.005-5 mass parts normally with respect to 100 mass parts of resin components (thermosetting compound and photocurable compound) contained in a composition, Preferably it is 0.02-2. Part by mass. Two or more of these light stabilizers may be used in combination.

  The reflection layer can be produced by (1) mixing a hollow particle with (1) a thermosetting compound and / or a photocurable compound, and then polymerizing and curing with heat or light. In the reflective layer preparation process, a polymerization initiator may be further added to accelerate the polymerization reaction. Although the polymerization initiator to be used is not specifically limited, For example, a radical polymerization initiator can be used.

  Specific examples of the radical polymerization initiator include ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, and methylcyclohexanone peroxide, 1,1,3,3-tetramethylbutyl Hydroperoxides such as hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, diisobutyryl peroxide, bis-3,5,5-trimethylhexanol peroxide, lauroyl peroxide, benzoyl peroxide, m- Diacyl peroxides such as toluylbenzoyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) Xanthone, 1,3-bis (t-butylperoxyisopropyl) hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexene, etc. Dialkyl peroxides, 1,1-di (t-butylperoxy-3,5,5-trimethyl) cyclohexane, 1,1-di-t-butylperoxycyclohexane, 2,2-di (t-butylperoxy) Peroxyketals such as butane, 1,1,3,3-tetramethylbutylperoxyneodicarbonate, α-cumylperoxyneodicarbonate, t-butylperoxyneodicarbonate, t-hexylperoxypivalate, t-butylperoxypi Valate, 1,1,3,3-tetramethylbutylperoxy-2 -Ethylhexanoate, t-amylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, di-t-butylperoxyhexahydroterephthalate, 1, 1,3,3-tetramethylbutylperoxy-3,5,5-trimethylhexanoate, t-amylperoxy3,5,5-trimethylhexanoate, t-butylperoxy3,5,5-trimethylhexanoate , T-butylperoxyacetate, t-butylperoxybenzoate, alkyl peresters such as dibutylperoxytrimethyladipate, di-3-methoxybutylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, bis (1,1-butyl Cyclohexa Xyldicarbonate), diisopropyloxydicarbonate, t-amylperoxyisopropylcarbonate, t-butylperoxyisopropylcarbonate, t-butylperoxy-2-ethylhexylcarbonate, 1,6-bis (t-butylperoxycarboxy) hexane, and the like. Examples thereof include oxycarbonates. Moreover, perhexa 3M-95 (Nippon Yushi Co., Ltd.), azobisisobutyronitrile, etc. are mentioned.

  The radical polymerization initiators may be used alone or in combination of two or more. The amount used is usually 0.01 to 5 parts by mass, preferably 0.05 to 1.0 parts by mass, when the total amount of the thermally polymerizable compound and the photopolymerizable compound is 100 parts by mass.

  In the present invention, preferably, a thermosetting compound or a photocurable compound is polymerized and used as a reflector. “To make a reflector simultaneously with polymerization” means, for example, obtaining a reflector only by an operation of curing a thermosetting compound or a photocurable compound on a substrate. For example, the composition constituting the liquid reflective layer is applied directly to the substrate without using a solvent, and then the polymerization is completed by energy such as light or heat to form a reflector.

The following methods (A) and (B) for producing a reflector do not correspond to “a reflector at the same time as polymerization”.
(A) A polymer of the composition constituting the reflective layer is dissolved in a solvent or the like, applied to a substrate and dried to obtain a reflector.
(B) A polymer of the composition constituting the reflective layer is injection-molded or extruded, and the resulting reflective layer and substrate are combined to form a reflector.

FIG. 1 is a schematic cross-sectional view showing an embodiment of an optical semiconductor device using the reflector of the present invention.
In the optical semiconductor device 1 of FIG. 1, the anatase-type titanium oxide-containing substrate 10 (hereinafter sometimes simply referred to as the substrate 10) is open in the light emitting direction, and the hollow particle-containing reflective layer 20 (hereinafter, In some cases, the reflective layer 20 may be simply laminated. Two lead frames 12 (conductive portions) are inserted into the base 10, an optical semiconductor element 24 is mounted on one lead frame 12, and the other lead frame 12 and the optical semiconductor element 24 are connected by wire bonding 22. It is electrically connected via. The opening formed by the base 10 is sealed with a sealing material 30.

  In general, the optical semiconductor device shown in FIG. 1 has a hollow particle-containing composition in which an optical semiconductor element is fixed to an anatase-type titanium oxide-containing substrate integrally formed with a lead frame, and then the optical semiconductor element is wired by wire bonding. Can be produced by coating and curing.

For example, when the reflective layer 20 shown in FIG. 1 is formed by the method (A), it is necessary to fill the concave portion of the substrate 10 with the polymerizable composition solution. However, since the optical semiconductor element is fixed to the opening of the substrate 10, when the reflective layer 20 is formed by the method (A), the surface of the optical semiconductor element is simultaneously covered with the reflective layer. It becomes difficult to extract light from the element.
Moreover, if the polymer is shaped as in the method (B) above, it can be formed into a concave shape. However, in the method (B), it is necessary to expose the polymer to a considerably high temperature for several minutes. During this time, the polymer deteriorates and becomes colored, and thus a reduction in reflectance is inevitable.

The base 10 of the optical semiconductor device 2 has a size of 5 mm, but the present invention is not limited to this size, and may be a size of 2 mm, 10 mm, etc. depending on the application.
When the substrate is concave as shown in FIG. 2, the thickness of the hollow particle-containing reflective layer is not constant, but preferably the maximum thickness is 0.05 mm to 3 mm, more preferably 0.25 to 2 mm. is there.

  The shape of the substrate 10 may be a flat shape in addition to the concave shape. When the shape of the substrate 10 is planar, the thickness of the substrate 10 is preferably 0.01 to 3 mm, more preferably 0.03 to 2 mm, from the balance of the strength and reflectance of the substrate. The thickness of the reflective layer 20 laminated on the substrate 10 is preferably as thick as possible from the viewpoint of reflectivity. However, considering the downsizing of the optical semiconductor device, it is preferably 0.01 to 3 mm, more preferably 0.25 to 0.25. 2 mm.

The materials used in the following examples and comparative examples are shown below.
[Matrix resin]
Zalek 130ZC (crystalline polystyrene, manufactured by Idemitsu Kosan Co., Ltd.)
[Titanium oxide]
A220 (anatase type titanium oxide, manufactured by Ishihara Sangyo Co., Ltd.)
A950 (anatase type titanium oxide, manufactured by Sakai Chemical Industry Co., Ltd.)
PF-726 (rutile titanium oxide, manufactured by Ishihara Sangyo Co., Ltd.)
[Thermosetting resin and photocurable resin]
Adamantate AM (methacrylic ester composition, 1-adamantyl methacrylate, manufactured by Idemitsu Kosan Co., Ltd.) / Perhexa HC (manufactured by NOF Corporation) = 100 / 0.1 (mass ratio)
XJL-0012A (silicone resin, manufactured by Nippon Pernox Co., Ltd.)
XJL-0012B (silicone resin, manufactured by Nippon Pernox Co., Ltd.)
KER2500A (silicone resin, manufactured by Shin-Etsu Chemical Co., Ltd.)
KER2500B (silicone resin, manufactured by Shin-Etsu Chemical Co., Ltd.)
[Hollow particles]
XX06BZ (crosslinked acrylic hollow particles, average particle size 5 μm, average pore size 1-2 μm, UV transmittance of crosslinked acrylic 84% (wavelength 350 nm, thickness 250 μm), manufactured by Sekisui Plastics Co., Ltd.)
HSC-110C (glass-based hollow particles, average particle diameter 13 μm, average pore diameter 9 μm, UV transmittance of glass> 90% (wavelength 350 nm, thickness 250 μm), manufactured by Potters Valotini Co., Ltd.)
[Non-hollow reflective filler]
Tismo D101 (potassium titanate fiber, manufactured by Otsuka Chemical Co., Ltd.)
[Radical polymerization initiator]
Perhexa HC (manufactured by NOF Corporation)

Production Example 1
60 parts by mass of syndiotactic polystyrene 130ZC, 30 parts by mass of anatase-type titanium dioxide A220, and 10 parts by mass of glass fiber JAFT164G (Asahi Fiber Glass Co., Ltd.) are blended and dry blended, and then twin screw extrusion with an inner diameter of 30 mm. It was put into a hopper of the machine, melt-kneaded at a barrel temperature of 285 ° C., and then pelletized. The obtained pellets were dried at 100 ° C. for a whole day and night, and then injection molded at a barrel temperature of 280 ° C. and a mold temperature of 150 ° C. (mirror mold) to obtain a square plate-like white molded body 1 of 3 cm × 3 cm × 1 mm.

Production Example 2
After blending 55 parts by weight of syndiotactic polystyrene 130ZC, 25 parts by weight of anatase-type titanium dioxide A950 and 20 parts by weight of glass fiber JAFT164G, they were dry-blended and then put into a hopper of a twin screw extruder with an inner diameter of 30 mm. After melt-kneading at a temperature of 285 ° C., pellets were obtained. The obtained pellets were dried at 100 ° C. for a whole day and night, and then injection molded at a barrel temperature of 280 ° C. and a mold temperature of 150 ° C. (mirror mold) to obtain a square plate-like white molded body 2 of 3 cm × 3 cm × 1 mm.

Production Example 3
After blending 55 parts by mass of syndiotactic polystyrene 130ZC, 25 parts by mass of rutile titanium oxide PF-726, and 20 parts by mass of glass fiber JAFT164G, the mixture was dry blended and charged into a hopper of a twin screw extruder having an inner diameter of 30 mm. After melt-kneading at a barrel temperature of 285 ° C., pellets were obtained. The obtained pellets were dried at 100 ° C. all day and night, and then injection molded at a barrel temperature of 280 ° C. and a mold temperature of 150 ° C. (mirror mold) to obtain a square plate-like white molded body 3 of 3 cm × 3 cm × 1 mm.

Example 1
According to the mixing ratio shown in Table 1, 70 parts by mass of a mixture of adamantate AM and perhexa HC (adamantate AM / perhexa HC = 100 / 0.1 (mass ratio)) and 30 parts by mass of XX06BZ (crosslinked acrylic hollow particles) Mixing was performed to prepare a composition containing hollow particles. The obtained composition was applied to the white molded body 1, heat-treated at 110 ° C. for 3 hours, and further heat-treated at 160 ° C. for 1 hour to cure the composition to obtain a laminate having a thickness of about 300 μm.
The following evaluation was performed about the obtained laminated body. The results are shown in Table 2.

[Initial reflectance of laminate]
Using a self-recording spectrophotometer UV-2400PC (manufactured by Shimadzu Corporation) equipped with a multipurpose large sample chamber unit MPC-2200 (manufactured by Shimadzu Corporation), reflection of the laminate in the wavelength range of 700 to 300 nm. The rate (%) was measured. Incidentally, barium sulfate was used as a reference.

[Reflectance of laminate after UV irradiation]
Using a weather resistance tester solarbox 1500e (manufactured by Jusco International Co., Ltd.), the reflective layer of the laminate was irradiated with ultraviolet light at an output of 500 W / m ² for 1000 hours. After the ultraviolet irradiation, the reflectance of the laminate was measured by the above method.

[Reflectance of laminate after heat treatment]
The laminate was put into an oven set at 160 ° C. and heat-treated for 5 hours. After the heat treatment, the reflectance of the laminate was measured by the above method.

Examples 2-7 and Comparative Examples 1-5
Compositions were prepared at the blending ratios shown in Table 1, respectively. The obtained composition was applied on the molded body shown in Table 1, and the composition was cured under the heat treatment conditions shown in Table 1, to obtain a laminate having a thickness of about 300 μm. In addition, the silicone type composition A of Table 1 is a silicone resin composition which is XJL0012A: XJL0012B = 100: 5 (mass ratio), and the silicone type composition B is KER2500A: KER2500B = 50: 50 (mass). Ratio) is a silicone resin composition.
The obtained laminate was evaluated in the same manner as in Example 1. The results are shown in Table 2. In addition, some roughness was confirmed on the surface of the laminate of Comparative Example 4. Further, in Comparative Example 5, the composition could not be uniformly applied to the substrate, and the thickness of the reflective layer was 1 mm or more and the surface was extremely rough.

Comparative Example 6
The white molded body 1 produced in Production Example 1 was evaluated in the same manner as in Example 1. The results are shown in Table 2.

  The reflector of the present invention can be used for lamp reflectors for liquid crystal displays, reflectors for showcases, reflectors for illumination, LED reflectors, and the like. The reflector for LED can be used for various OA equipment, electrical and electronic equipment and parts, automobile parts, and the like such as a display, a destination display board, in-vehicle illumination, a signal light, an emergency light, a mobile phone, and a video camera.

It is a schematic sectional drawing which shows one Embodiment of the optical semiconductor device using the reflector of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical semiconductor device 10 Anatase type titanium oxide containing base | substrate 12 Lead frame 20 Hollow particle containing reflection layer 22 Wire bonding 24 Optical semiconductor element 30 Sealing material

Claims (7)

The reflector for optical semiconductors which is a laminated body of the base | substrate which consists of a composition containing an anatase type titanium oxide, and the reflection layer which consists of a composition containing following component (1) and (2).
(1) Thermosetting compound and / or photocurable compound: 40 to 80% by mass
(2) Hollow particles made of a material having a transmittance of 50% or more for ultraviolet rays having a wavelength of 350 nm: 20 to 60% by mass   The reflector for an optical semiconductor according to claim 1, wherein the thermosetting compound or the photocurable compound is a silicone compound, an epoxy compound, or a (meth) acrylic ester compound.   The optical semiconductor reflector according to claim 1, wherein the hollow particles are a crosslinked resin or an inorganic compound.   The optical semiconductor reflector according to claim 1, wherein the hollow particles are a crosslinked styrene resin, a crosslinked acrylic resin, inorganic glass, or silica.   The reflector for optical semiconductors according to any one of claims 1 to 4, wherein the composition containing the anatase-type titanium oxide contains crystalline polystyrene, a liquid crystal polymer, or a polyamide resin.   6. The optical semiconductor reflector according to claim 1, wherein the substrate has a reflectance of 60% or more with respect to ultraviolet rays having a wavelength of 400 nm.   The optical semiconductor device containing the reflector for optical semiconductors in any one of Claims 1-6.

Images