JP5740097B2 - High heat conductive resin molding for heat sink - Google Patents

Description

  The present invention provides a resin obtained from a thermoplastic resin composition that achieves both high thermal conductivity and electrical insulation, is excellent in light resistance, moldability, high light resistance, and high whiteness, and has a high reflectance. It relates to a molded body. More specifically, the present invention relates to a thermoplastic resin molded article suitable for various uses, particularly as a lighting fixture member, which is a high thermal conductive resin but has a low density and can contribute to weight reduction of a lighting fixture member or a portable electronic device.

  The performance of electronic devices has been remarkably improved, the degree of integration has increased with the performance improvement, and the amount of heat generated per volume has increased remarkably. Therefore, how to take measures against heat in electronic device design is an important issue for the performance and long-term reliability of the device. In particular, in recent years, the use of LEDs has been expanded and applied to displays and liquid crystal backlights and lighting, and countermeasures against heat have become a problem. In many cases, such heat release is performed by quickly spreading the heat of the heating element using a heat sink or a heat spreader, and increasing the contact surface with the refrigerant such as air or water.

  Conventional heat sinks use copper and aluminum materials to produce products by cutting, die casting or hot extrusion. Since these metals generally have low emissivity, there are some metals whose emissivity is improved by surface processing such as alumite or painting. There are also products with metal heat pipes installed to further improve heat dissipation. When these metal heat sinks are further reduced in size, weight, or complicated shape, the productivity of metal such as die-casting is poor and the shape is limited. Therefore, a resin material has attracted attention as a material that changes to metal.

  However, when a thermoplastic resin molded body is applied to various uses such as personal computers and display casings, electronic device materials, automobile interior and exterior, lighting fixture members, and portable electronic devices such as mobile phones, plastic is a metal material. Since heat conductivity is lower than that of an inorganic material, it may be a problem that generated heat is difficult to escape. In order to solve such problems, attempts have been widely made to obtain a high thermal conductive resin composition by blending a large amount of a high thermal conductive inorganic substance in a thermoplastic resin. As the high heat conductive inorganic compound, high heat conductive inorganic materials such as graphite, carbon fiber, low melting point metal, alumina, aluminum nitride, etc. are used, and usually have a high content of 30% by volume or more, and further 50% by volume or more. It is necessary to mix in the resin. (Patent Document 1)

Among these resin compositions, those using graphite, carbon fiber, low melting point metal, etc. can obtain a resin molded body having a relatively high thermal conductivity, but the obtained resin molded body has conductivity. Therefore, it is difficult to differentiate from metal, and its application is limited. (Patent Document 2)
On the other hand, those using alumina can achieve both electrical insulation and high thermal conductivity, but since alumina is higher in density than resin, the density of the resulting composition is also increased, and portable electronic devices and lighting fixture members However, it is difficult to meet the demand for weight reduction and the like, and there is a problem that the thermal conductivity is not improved so much. Further, when aluminum nitride is used, a composition having a relatively high thermal conductivity can be obtained, but there is a concern about the hydrolyzability of aluminum nitride.

  Furthermore, the thermoplastic resin composition highly filled with these fillers greatly reduces moldability due to the high filler content, and injection molding is very difficult with molds having practical shapes or molds having pin gates. There is a problem that it is difficult. In order to improve the moldability of a highly thermally conductive thermoplastic resin highly filled with a filler, for example, a method of adding a liquid organic compound at room temperature is exemplified (Patent Document 3).

  However, in such a method, there is a problem that a liquid organic compound bleeds out during injection molding and contaminates the mold. Various other methods for improving formability have been studied, but no effective method has been found yet.

  On the other hand, in the past, thermosetting resins were mainly used for lighting fixture members such as light bulb sockets and arc tube holders, but conversion to thermoplastic resins has been promoted due to problems in processability and cost. In this case, it is necessary to have high light resistance as a resin, and in order to satisfy this, a white thermoplastic polyester resin composition to which a large amount of a white pigment containing, for example, titanium oxide is added is exemplified (Patent Document 4).

  However, in such a method, there is a problem that it is not possible to meet the demands for lighting fixture members that have been demanded in recent years, such as compactness, long life, and high functionality such as high thermal conductivity.

Patent No. 4407250 JP2009-16415 Japanese Patent No. 3948240 Patent No. 1959144

  In view of the above-mentioned present situation, the present invention has excellent properties such as high thermal conductivity, electrical insulation, low density, good moldability, high light resistance, high whiteness and the like, and further has excellent reflectance. It is to realize the difficult task of obtaining a body.

  As a result of diligent research on a method that satisfies all of high thermal conductivity, electrical insulation, low density, moldability, high light resistance, and high white color and can easily provide high reflectivity, the inventor has obtained a specific structure. The present inventors have found that a desired molded article can be easily formed by using a hexagonal boron nitride powder having a specific shape with a resin in combination.

That is, the present invention relates to the following [1] to [ 5 ].
[1] A high heat conductive resin molding for heat sink partially or entirely formed of a high heat conductive resin composition, wherein the high heat conductive resin composition is a thermoplastic polyester resin (A), number average It contains at least a scale-shaped hexagonal boron nitride powder (B) having a particle size of 15 μm or more, a whiteness W of 90 or more, and a graphitization index GI of 2.0 or less, and glass fiber , of (A) / (B) volume ratio is obtained from the resin composition is in the range of 85 / 15-25 / 75, and molded by an injection molding method, whiteness 80 or more and Ri der total light reflectance of 50% or more, 120 ℃ in an atmosphere at the time of seven days continuously irradiated from a distance of 10cm the 400W mercury lamp, the color difference between before and after irradiation △ E heat sink for highly thermally conductive resin formed body, characterized in der Rukoto 10 or less.
[2] The highly heat conductive resin molded body for a heat sink according to [1], wherein the scale-shaped hexagonal boron nitride powder (B) has a number average particle diameter of 30 μm or more.
[3] The highly heat-conductive resin molded article for a heat sink according to [1] or [2], wherein the scale density hexagonal boron nitride powder (B) has a tap density of 0.6 g / cm ³ or more. .
[ 4 ] The thermal diffusivity in the surface direction of the molded body is twice or more the thermal diffusivity in the thickness direction of the molded body, and the thermal diffusivity in the surface direction of the molded body is 0.5 mm ² / sec or more. The high heat conductive resin molded article for a heat sink according to any one of [1] to [ 3 ].
[5] The thermal conductivity of the formed features is not less 1W / m · K or more, and characterized in that further surface resistivity is ^{10 11} Omega above, [1] any one of - [4] A highly heat-conductive resin molded product for a heat sink as described in 1.

  By using the method of the present invention, a thermoplastic resin molded article having excellent reflectance can be obtained, and the thermoplastic resin composition itself used for the molded article has high thermal conductivity, electrical insulation, low density. In addition, it has good moldability, high light resistance, and high whiteness, and a resin molded body that is very useful for reducing the weight of a lighting fixture member, portable electronic device, etc., heat countermeasures, etc. can be easily molded.

Example of heat sink shape It is the evaluation model used in the Example.

<Thermoplastic polyester resin>
Examples of the thermoplastic polyester resin of the component (A) of the present invention include amorphous thermoplastic polyester resins such as amorphous aliphatic polyester, amorphous semi-aromatic polyester, and amorphous wholly aromatic polyester, and crystals. Crystalline thermoplastic polyester resins such as crystalline aliphatic polyesters, crystalline semi-aromatic polyesters, crystalline wholly aromatic polyesters, liquid crystals such as liquid crystalline aliphatic polyesters, liquid crystalline semi-aromatic polyesters, and liquid crystalline wholly aromatic polyesters A thermoplastic thermoplastic polyester resin can be used. Among the thermoplastic polyester resins, specific examples of structures preferable as liquid crystalline thermoplastic polyester resins are:
-O-Ph-CO- structural unit (I),
-O-R3-O- structural unit (II),
-O-CH2CH2-O- structural unit (III) and -CO-R4-CO- structural unit (IV)
And a liquid crystalline polyester comprising the structural units of:
(However, R3 in the formula is

One or more groups selected from R4,

1 or more groups selected from (wherein X represents a hydrogen atom or a chlorine atom).

  The structural unit (I) is a structural unit generated from p-hydroxybenzoic acid, and the structural unit (II) is 4,4′-dihydroxybiphenyl, 3,3 ′, 5,5′-tetramethyl-4,4. '-Dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, phenylhydroquinone, methylhydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2-bis (4-hydroxyphenyl) propane and 4,4'- A structural unit generated from one or more aromatic dihydroxy compounds selected from dihydroxydiphenyl ether, a structural unit (III) is a structural unit generated from ethylene glycol, a structural unit (IV) is terephthalic acid, isophthalic acid, 4, 4 '-Diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, Selected from 1,2-bis (phenoxy) ethane-4,4′-dicarboxylic acid, 1,2-bis (2-chlorophenoxy) ethane-4,4′-dicarboxylic acid and 4,4′-diphenyl ether dicarboxylic acid Each of the structural units produced from one or more aromatic dicarboxylic acids is shown.

  Among these, liquid crystalline polyesters composed of structural units generated from p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, structural units generated from p-hydroxybenzoic acid, structural units generated from ethylene glycol, aromatics Structural units generated from dihydroxy compounds, liquid crystalline polyesters of structural units generated from terephthalic acid, structural units generated from p-hydroxybenzoic acid, structural units generated from ethylene glycol, liquid crystalline polyesters of structural units generated from terephthalic acid Can be used particularly preferably.

  Among the thermoplastic polyester resins, specific examples of the crystalline thermoplastic polyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polybutylene naphthalate, and poly 1,4-cyclohexylene diene. In addition to methylene terephthalate and polyethylene-1,2-bis (phenoxy) ethane-4,4'-dicarboxylate, etc., polyethylene isophthalate / terephthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / decane dicarboxylate and poly Examples thereof include crystalline copolyesters such as cyclohexanedimethylene terephthalate / isophthalate.

  Among these crystalline polyesters, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, polybutylene naphthalate, poly 1,4-cyclohexylene dimethylene terephthalate, Etc. are preferably used. Among these, polyalkylene terephthalate-based thermoplastic polyester resins such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and the like are preferable from the viewpoint that the crystallization speed is optimal.

  In the resin composition used for the high thermal conductive resin molding of the present invention, the polyester resin may be used alone or in combination of two or more. When two or more types are used in combination, the combination is not particularly limited, and two or more types of components having different chemical structures, molecular weights, crystal forms, and the like can be arbitrarily combined.

  Among these various thermoplastic polyester resins, it is preferable to use a highly crystalline or liquid crystalline resin because the resin itself has high thermal conductivity. Depending on the resin, the crystallinity may change depending on the molding conditions. In such a case, the thermal conductivity of the resulting resin molding is increased by selecting molding conditions that result in high crystallinity. be able to.

  Various thermoplastic resins other than the thermoplastic polyester resin (A) can be further used for the resin composition used for the highly thermally conductive resin molded article of the present invention. The thermoplastic resin other than (A) may be a synthetic resin or a resin existing in nature. When using a thermoplastic resin other than (A), the amount used is preferably 0 to 100 parts by weight, more preferably 0 with respect to 100 parts by weight, considering the balance between moldability and mechanical properties. ~ 50 parts by weight.

Examples of the thermoplastic resin other than (A) include aromatic vinyl resins such as polystyrene, vinyl cyanide resins such as polyacrylonitrile, chlorine resins such as polyvinyl chloride and polyvinylidene chloride, and polymethacrylates such as polymethyl methacrylate. Acrylic acid ester resins and polyacrylic acid ester resins, polyolefin resins such as polyethylene, polypropylene and cyclic polyolefin resins, polyvinyl ester resins such as polyvinyl acetate, polyvinyl alcohol resins and their derivative resins, polymethacrylic acid resins Resins, polyacrylic acid resins and their metal salt resins, polyconjugated diene resins, polymers obtained by polymerizing maleic acid, fumaric acid and their derivatives, polymers obtained by polymerizing maleimide compounds, polyamides Resin, polycarbonate Resin, polyurethane resin, polysulfone resin, polyalkylene oxide resin, cellulose resin, polyphenylene ether resin, polyphenylene sulfide resin, polyketone resin, polyimide resin, polyamideimide resin, polyetherimide resin, Polyether ketone resins, polyether ether ketone resins, polyvinyl ether resins, phenoxy resins, fluorine resins, silicone resins, liquid crystal polymers, and random block graft copolymers of these exemplified polymers , Etc. These thermoplastic resins other than (A) may be used alone or in combination of one or more. When two or more resins are used in combination, a compatibilizer or the like can be added as necessary. Any thermoplastic resin other than (A) may be appropriately used according to the purpose.

  Among these thermoplastic resins other than (A), part or all of the resin is a thermoplastic resin having crystallinity or liquid crystallinity, and the resulting resin composition tends to have high thermal conductivity. This is preferable from the viewpoint of easy inclusion of the inorganic compound (B) in the resin. These thermoplastic resins having crystallinity or liquid crystallinity are part of the resin such that only a specific block in the molecule of the block or graft copolymer resin is crystalline or liquid crystalline even if the entire resin is crystalline. Only may be crystalline or liquid crystalline. There is no particular limitation on the crystallinity of the resin. Further, as a thermoplastic resin other than (A), a polymer alloy of an amorphous resin and a crystalline or liquid crystalline resin can also be used. At this time, the crystallinity of the resin is not particularly limited.

  Some thermoplastic resins other than the resin (A) having a crystallinity or liquid crystallinity may be used alone or molded under specific molding process conditions, even if they can be crystallized. In some cases, some resins may be amorphous. When such a resin is used, it is possible to adjust the amount and method of addition of the inorganic compound (B), or to devise a molding method such as stretching or post-crystallization, so that In some cases, part or the whole can be crystallized.

  Among the thermoplastic resins having crystallinity or liquid crystallinity, preferred examples of the resin include polyphenylene sulfide resin, crystalline polyolefin resin, polyolefin block copolymer, and the like. A functional resin or a liquid crystalline resin can be used.

  Moreover, the impact strength of the resin of (A) can also be improved by using resin which has elasticity for thermoplastic resins other than (A). Since these elastic resins are excellent in the impact strength improving effect of the obtained resin composition, it is preferable that at least one glass transition point thereof is 0 ° C. or lower, more preferably −20 ° C. or lower.

  The elastic resin is not particularly limited, and examples thereof include diene rubbers such as polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and (meth) acrylic acid alkyl ester-butadiene rubber; acrylic rubber, ethylene-propylene rubber, and siloxane rubber. Rubbery polymer such as diene rubber and / or rubbery polymer selected from the group consisting of aromatic vinyl compound, vinyl cyanide compound and alkyl (meth) acrylate with respect to 10-90 parts by weight of rubbery polymer. A rubber-like copolymer obtained by polymerizing at least 10 parts by weight of at least one monomer and 10 parts by weight or less of another vinyl compound copolymerizable therewith; various polyolefin resins such as polyethylene and polypropylene; ethylene Propylene copolymer, ethylene-butene copolymer, Ethylene-α olefin copolymer; olefin copolymer such as propylene-butene copolymer; copolymer polyolefin resin modified with various copolymer components such as ethylene-ethyl acrylate copolymer; ethylene-glycidyl Methacrylate copolymer, ethylene-maleic anhydride copolymer, ethylene-propylene-glycidyl methacrylate copolymer, ethylene-propylene-maleic anhydride copolymer, ethylene-butene-glycidyl methacrylate copolymer, ethylene-butene-anhydrous Modified polyolefin resin modified with various functional components such as maleic acid copolymer, propylene-butene-glycidyl methacrylate copolymer, propylene-butene-maleic anhydride copolymer; styrene-ethylene-propylene copolymer ,styrene -Styrenic thermoplastic elastomers such as ethylene-butene copolymer and styrene-isobutylene copolymer.

  When the elastic resin is added, the addition amount is usually 150 parts by weight or less, preferably 0.1 to 100 parts by weight, more preferably 0.2 parts per 100 parts by weight of the resin (A). ~ 50 parts by weight. If it exceeds 150 parts by weight, the rigidity, heat resistance, thermal conductivity, etc. tend to decrease.

<Scale-shaped hexagonal boron nitride>
The scale-shaped hexagonal boron nitride powder (B) having a number average particle size of 15 μm or more, a whiteness W of 90 or more and a graphitization index GI of 2.0 or less used in the present invention is produced by various known methods. can do. As a general production method, boron oxide or boric acid serving as a boron source, melamine serving as a nitrogen source, urea, ammonia, etc. are reacted in advance if necessary, and then in the presence of an inert gas such as nitrogen or Heated to about 1000 ° C. under vacuum to synthesize a turbulent boron nitride, and then further heated to about 2000 ° C. in the presence of an inert gas such as nitrogen or argon or under vacuum to promote crystallization. Examples thereof include a method of forming a crystalline boron nitride crystal powder. By such a production method, scale-shaped hexagonal boron nitride having a number average particle diameter of about 5 to 15 μm is generally obtained. However, the scale-shaped hexagonal boron nitride used in the present invention grows primary crystals greatly by using a special production method, the number average particle size is 15 μm or more, the whiteness W is 90 or more, and the graphitization index GI is 2 0.0 or less.

  As a method for obtaining a scale-shaped hexagonal boron nitride powder (B) having a number average particle size of 15 μm or more, a whiteness W of 90 or more and a graphitization index GI of 2.0 or less, for example, an inert gas atmosphere such as nitrogen or argon In the presence of flux compounds that become liquid at high temperatures such as lithium nitrate, calcium carbonate, sodium carbonate, and metallic silicon, nitrogen sources such as melamine and urea, or nitrogen such as nitrogen gas and ammonia gas By firing the source gas and the boron source compound such as boric acid and boron oxide at a high temperature of about 1700 to 2200 ° C., crystal growth is promoted in the flux compound, and crystal grains having a large particle size The production method is not limited to such a method, and various methods can be used.

  The scale-shaped hexagonal boron nitride powder (B) having a particularly large number average particle diameter thus obtained was filled in the resin by injection molding or extrusion molding of the resin composition filled in the resin. The scale-shaped hexagonal boron nitride powder is easily oriented in the surface direction of the compact. By obtaining such an orientation state of the boron nitride powder, it is possible to make the thermal diffusivity measured in the surface direction of the molded body more than twice the thermal diffusivity measured in the thickness direction. That is, the scale-shaped hexagonal boron nitride powder (B) having a particularly large number-average particle diameter has a property of more easily transferring heat in the scale-shaped surface direction than boron nitride having a small number-average particle diameter. .

  The number average particle diameter of the scale-shaped hexagonal boron nitride powder (B) used in the present invention is required to be 15 μm or more, preferably 20 μm or more, more preferably 25 μm or more, and further preferably 30 μm or more. Preferably it is 40 micrometers or more. As the number average particle size is larger, when the resin composition filled with the scale-shaped hexagonal boron nitride powder is used as a molded body, the thermal conductivity of the molded body as a whole tends to be improved, and the molding is performed. It is recognized that the ratio of the thermal diffusivity measured in the body surface direction to the thermal diffusivity measured in the thickness direction, that is, the thermal diffusion anisotropy tends to increase. The upper limit of the number average particle diameter is generally 1 mm or less. When the thickness is 1 mm or more, the moldability tends to be lowered due to powder clogging in the gate portion of the mold during injection molding.

  The whiteness W of the scale-shaped hexagonal boron nitride powder (B) used in the present invention is preferably 90 or more, more preferably 92 or more, and most preferably 95 or more. As the whiteness is higher, when the resin composition filled with the scale-shaped hexagonal boron nitride powder is used as a molded body, the whiteness of the molded body tends to increase.

  Furthermore, the graphitization index GI of the scale-shaped hexagonal boron nitride powder (B) used in the present invention is preferably 2.0 or less, more preferably 1.8 or less, still more preferably 1.6 or less, and most preferably 1. .3 or less. The lower the graphitization index value, the higher the crystallinity of the scale-shaped hexagonal boron nitride powder, and when the resin composition filled with the scale-shaped hexagonal boron nitride powder is used as a molded body, Since the tendency which the thermal conductivity of this improves is recognized, it is preferable.

  The particle size here is calculated from the diameter of a circle when the shape is circular when the projection area is observed to be the largest among the scaly particles. When the shape is not circular, the longest dimension in the plane is called the particle size. That is, the major axis of the ellipse in the case of an elliptical shape, and the length of the diagonal line of the rectangle in the case of a rectangle is taken as the particle size.

  The powder has a scaly shape means that the dimension of the major axis when observed so that the projected area of the powder becomes the largest is five times the dimension of the shortest side when observed so that the projected area of the powder becomes the smallest. The major axis dimension when observed so that the projected area of the powder becomes the largest is defined as being less than five times the minor axis dimension. The ratio of the major axis dimension when the projection area is observed to be the largest and the minor dimension when the projection area is observed to be the smallest is preferably such that the major axis dimension is at least six times the minor dimension. More preferably, it is 7 times or more. The ratio of the major axis dimension to the minor axis dimension when observed so that the projected area of the powder becomes the largest is preferably less than 4.5 times the major axis dimension, more preferably less than four times the minor axis dimension. .

  Moreover, the whiteness W here can be calculated by the following equation (1) from the lightness (L), hue, and saturation (a, b) of the color of the powder measured using a colorimetric color difference meter.

    W = 100-{(100-L) 2 + a2 + b2} 1/2 (1)

  Further, the graphitization index GI here refers to the integrated intensity ratio of (100), (101) and (102) diffraction lines in the diffraction diagram in the powder X-ray diffraction measurement of the scale-shaped hexagonal boron nitride powder (that is, From the area ratio, it can be calculated by the following equation (2).

    GI = [area {(100) + (101)}] / [area (102)] (2)

The tap density of the scale-shaped hexagonal boron nitride powder (B) used in the present invention is determined by impact by tapping the scale-shaped hexagonal boron nitride powder in a 100 cc container for density measurement using a general powder tap density measuring device. After hardening, it is calculated by a method of rubbing excess powder on the top of the container with a blade. The larger the tap density measured in this way, the easier the resin is filled. The value of the tap density preferably 0.6 g / cm ³ or more, more preferably 0.65 g / cm ³ or more, more preferably 0.7 g / cm ³ or more, and most preferably 0.75 g / cm ³ or more.

  In the thermoplastic resin composition used for the high thermal conductive resin molding of the present invention, the ratio of the resin (A) to the scale-shaped hexagonal boron nitride powder (B) is 85 (A) / (B). / 15 to 25/75 is preferable. In view of the fact that the greater the amount of (A) used, the more the impact resistance, surface properties and molding processability of the resulting molded body will improve, and melt kneading tends to be easier, and the amount of (B) used is From the viewpoint that thermal conductivity tends to improve as the amount increases, the volume ratio is preferably 80/20 to 33/67, more preferably 75/25 to 35/65, and still more preferably 73/27 to 40/60. Most preferably, it is 70/30 to 45/55.

  In order to further improve the performance of the high thermal conductive resin molding of the present invention, a high thermal conductive inorganic compound having a single thermal conductivity of 1 W / m · K or more can be used in combination. In order to further improve the thermal conductivity of the molded body, the thermal conductivity of the inorganic compound used alone is preferably 2 W / m · K or more, more preferably 5 W / m · K or more, and even more preferably 10 W / m · K or more, most preferably 30 W / m · K or more. The upper limit of the thermal conductivity of the high thermal conductivity inorganic compound alone is not particularly limited, and it is preferably as high as possible. Generally, it is preferably 3000 W / m · K or less, more preferably 2500 W / m · K or less. Used.

In particular, when the molded body is used for applications requiring high electrical insulation, a compound exhibiting electrical insulation is preferably used as the high thermal conductivity inorganic compound. Specifically, the electrical insulating property indicates that the volume resistivity is 1 Ω · cm or more, preferably 10 Ω · cm or more, more preferably 10 ⁵ Ω · cm or more, and still more preferably 10 ^It is preferable to use those having a resistance of ¹⁰ Ω · cm or more, most preferably 10 ¹³ Ω · cm or more. The upper limit of the volume specific electrical resistivity is not particularly limited, but is generally 10 ¹⁸ Ω · cm or less.

  Specific examples of highly thermally conductive inorganic compounds that exhibit electrical insulation include aluminum oxide, magnesium oxide, silicon oxide, beryllium oxide, copper oxide, cuprous oxide, and other metal oxides, aluminum nitride, and nitride Metal nitrides such as silicon, metal carbides such as silicon carbide, metal carbonates such as magnesium carbonate, insulating carbon materials such as diamond, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, cubic nitriding Various boron nitrides having a form other than (B) such as boron and turbulent boron nitride can be exemplified. Aluminum oxide may be a compound compounded with other elements such as mullite.

  Among them, since it has excellent electrical insulation properties, metal nitrides other than (B) such as boron nitride, aluminum nitride, and silicon nitride, metal oxides such as aluminum oxide, magnesium oxide, and beryllium oxide, and metal carbonates such as magnesium carbonate A metal hydroxide such as a salt, aluminum hydroxide or magnesium hydroxide, or an insulating carbon material such as diamond can be more preferably used. Among aluminum oxides, α-alumina is preferable because of its excellent thermal conductivity. These may be used alone or in combination of two or more.

  Various shapes can be applied to these highly heat-conductive inorganic compounds. For example, particles, fine particles, nanoparticles, aggregated particles, tubes, nanotubes, wires, rods, needles, plates, rugby balls, hexahedrons, large particles and fine particles are complexed Various shapes such as composite particles, irregular shapes, and liquids can be exemplified. These high thermal conductivity inorganic compounds may be natural products or synthesized ones. In the case of a natural product, there are no particular limitations on the production area and the like, which can be selected as appropriate. These high thermal conductive inorganic compounds may be used alone or in combination of two or more different shapes, average particle diameters, types, surface treatment agents and the like.

  These highly heat-conductive inorganic compounds have been surface-treated with various surface treatment agents such as a silane treatment agent in order to enhance the adhesion at the interface between the resin and the inorganic compound or to facilitate workability. Also good. It does not specifically limit as a surface treating agent, For example, conventionally well-known things, such as a silane coupling agent and a titanate coupling agent, can be used. Among them, an epoxy group-containing silane coupling agent such as epoxy silane, an amino group-containing silane coupling agent such as aminosilane, polyoxyethylene silane, and the like are preferable because they hardly reduce the physical properties of the resin. The surface treatment method of the inorganic compound is not particularly limited, and a normal treatment method can be used.

<Additives>
In order to further improve the heat resistance and mechanical strength of the resin composition, an inorganic compound other than those described above is further added to the resin composition used for the highly thermally conductive resin molded product of the present invention within a range not impairing the characteristics of the present invention. can do. There is no restriction | limiting in particular as such an inorganic compound. However, since the addition of these inorganic compounds may affect the thermal conductivity, attention should be paid to the amount added. These inorganic compounds may also be surface treated. When using these, it is preferable that the addition amount is 100 weight part or less with respect to 100 weight part of resin (A). When the addition amount exceeds 100 parts by weight, impact resistance and molding processability may be deteriorated. Preferably it is 50 weight part or less, More preferably, it is 10 weight part or less. In addition, as the addition amount of these inorganic compounds increases, the surface properties and dimensional stability of the molded product tend to deteriorate. Therefore, when these characteristics are important, the addition amount of the inorganic compound should be as small as possible. It is preferable to do.

  Moreover, in order to make the highly heat conductive resin molding of the present invention higher performance, heat stabilizers such as phenol stabilizers, sulfur stabilizers, phosphorus stabilizers, etc., alone or in combination of two or more. Is preferably added. Furthermore, as required, generally well-known stabilizers, lubricants, mold release agents, plasticizers, flame retardants other than phosphorus, flame retardant aids, ultraviolet absorbers, light stabilizers, pigments, dyes, charging You may add an inhibitor, an electroconductivity imparting agent, a dispersing agent, a compatibilizer, an antibacterial agent etc. in the range which has the effect of this invention individually or in combination of 2 or more types.

  It does not specifically limit as a manufacturing method of the resin composition used for the highly heat conductive resin molding of this invention. For example, it can be produced by drying the above-described components, additives and the like and then melt-kneading them in a melt-kneader such as a single-screw or twin-screw extruder. Moreover, when a compounding component is a liquid, it can also manufacture by adding to a melt-kneader on the way using a liquid supply pump etc.

  In the resin composition used for the high thermal conductive resin molding of the present invention, the moldability can be further improved by adding a crystallization accelerator such as a nucleating agent as necessary.

  Examples of the crystallization accelerator used in the present invention include higher fatty acid amides, urea derivatives, sorbitol compounds, higher fatty acid salts, aromatic fatty acid salts and the like, and these can be used alone or in combination of two or more. . Of these, higher fatty acid amides, urea derivatives, and sorbitol compounds are preferred because of their high effects as crystallization accelerators.

  Examples of the higher fatty acid amide include behenic acid amide, oleic acid amide, erucic acid amide, stearic acid amide, palmitic acid amide, N-stearyl behenic acid amide, N-stearyl erucic acid amide, ethylenebisstearic acid amide, ethylene Bisoleic acid amide, ethylene biserucic acid amide, ethylene bislauric acid amide, ethylene biscapric acid amide, p-phenylenebisstearic acid amide, ethylenediamine, stearic acid and sebacic acid polycondensate, etc. Acid amides are preferred.

  Examples of the urea derivative include bis (stearylureido) hexane, 4,4′-bis (3-methylureido) diphenylmethane, 4,4′-bis (3-cyclohexylureido) diphenylmethane, 4,4′-bis (3- Cyclohexylureido) dicyclohexylmethane, 4,4′-bis (3-phenylureido) dicyclohexylmethane, bis (3-methylcyclohexylureido) hexane, 4,4′-bis (3-decylureido) diphenylmethane, N-octyl-N ′ -Phenylurea, N, N'-diphenylurea, N-tolyl-N'-cyclohexylurea, N, N'-dicyclohexylurea, N-phenyl-N'-tribromophenylurea, N-phenyl-N'-tolylurea N-cyclohexyl-N′-phenylurea , Etc. are exemplified, especially bis (stearyl ureido) hexane are preferred.

  Examples of the sorbitol compound include 1,3,2,4-di (p-methylbenzylidene) sorbitol, 1,3,2,4-dibenzylidene sorbitol, 1,3-benzylidene-2,4-p-methylbenzylidene. Sorbitol, 1,3-benzylidene-2,4-p-ethylbenzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-benzylidene sorbitol, 1,3-p-methylbenzylidene-2,4-p-ethylbenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3,2,4-di (p- Ethylbenzylidene) sorbitol, 1,3,2,4-di (pn-propylbenzylidene) sorbi 1,3,2,4-di (p-i-propylbenzylidene) sorbitol, 1,3,2,4-di (pn-butylbenzylidene) sorbitol, 1,3,2,4-di ( p-s-butylbenzylidene) sorbitol, 1,3,2,4-di (pt-butylbenzylidene) sorbitol, 1,3,2,4-di (p-methoxybenzylidene) sorbitol, 1,3,2 , 4-Di (p-ethoxybenzylidene) sorbitol, 1,3-benzylidene-2,4-p-chlorobenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-benzylidenesorbitol, 1,3-p- Chlorbenzylidene-2,4-p-methylbenzylidene sorbitol, 1,3-p-chlorobenzylidene-2,4-p-ethylbenzylidene sorbitol, 1 3-p-methylbenzylidene-2,4-p-chlorobenzylidene sorbitol, 1,3-p-ethylbenzylidene-2,4-p-chlorobenzylidene sorbitol, and 1,3,2,4-di (p-chloro) Benzylidene) sorbitol, and the like. Among these, 1,3,2,4-di (p-methylbenzylidene) sorbitol and 1,3,2,4-dibenzylidenesorbitol are preferable.

  The amount of the crystallization accelerator used in the resin composition used for the high thermal conductive resin molding of the present invention is preferably 0.01 to 5 parts by weight with respect to 100 parts by weight of the resin (A) in terms of moldability. 0.03 to 4 parts by weight is more preferable, and 0.05 to 3 parts by weight is still more preferable. If it is less than 0.01 part by weight, the effect as a crystallization accelerator may be insufficient, and if it exceeds 5 parts by weight, the effect may be saturated. May be damaged.

<High thermal conductive resin molding>
The total light reflectance of the high thermal conductive resin molding of the present invention is preferably 50% or more and 100% or less, more preferably 60% or more and 100% or less, and further preferably 65% or more and 100% or less. Yes, most preferably 70% or more and 100% or less. In the illumination member, since light is absorbed when the reflectance is low, it is necessary to emit more light to achieve the same brightness. When the reflectance is 100% or more, it is considered that light is emitted in response to incident light, but it is not included in the preferred range because of an effect that is not expected of the present invention. Further, since the reflectance depends on both the material of the molded body and the molding conditions, the high reflectance also indicates that the present invention has good moldability.

  Here, the total light reflectance of the high thermal conductive resin molding of the present invention is a combination of regular reflectance and diffuse reflectance. Here, the regular reflectance refers to the ratio of the amount of light reflected at a reflection angle equal to the incident angle with respect to the amount of incident light. When the light incident surface is uneven, light that is reflected at a reflection angle different from the incident angle of the incident light is generated. The diffuse reflectance refers to the ratio of the amount of light reflected at a reflection angle different from the incident angle with respect to the amount of incident light. It is preferable that the reflectance at a wavelength of 550 nm is greater than or equal to the above numerical value, representing the visible light region (400 nm to 800 nm).

The whiteness of the high thermal conductive resin molding of the present invention is preferably 80 or more, more preferably 82 or more, and most preferably 85 or more.
Here, the whiteness of the highly thermally conductive resin molded product of the present invention is the lightness (L) of the color of the molded product measured using a colorimetric color difference meter, similar to the whiteness of the scale-shaped hexagonal boron nitride powder, From hue and saturation (a, b), it can be calculated by (1).

  The light resistance of the high thermal conductive resin molding of the present invention can be evaluated by the color difference of the sample accompanying the mercury lamp irradiation at a high temperature. For example, the color difference ΔE before and after irradiation when a 400 W mercury lamp is continuously irradiated from a distance of 10 cm for 7 days in a 120 ° C. atmosphere is evaluated. This ΔE needs to be 10 or less, preferably 8 or less, and most preferably 6 or less.

  Here, the color difference ΔE before and after irradiation with the mercury lamp is measured by the colorimetric colorimeter to measure the color tone L0, a0, b0 of the molded body before irradiation with the mercury lamp and the color tone L1, a1, b1 of the molded body after irradiation with the following formula ( 3).

  ΔE = {(L1-L0) 2+ (a1-a0) 2+ (b1-b0) 2} 1/2 (3)

  The high thermal conductive resin molding of the present invention is required to have high thermal conductivity as a molding. The thermal conductivity of the molded body is preferably 1 W / m · K or more, more preferably 2 W / m · K or more, and most preferably 3 W / m · K or more.

  The thermal conductivity of the high thermal conductive resin molding of the present invention as a molded body is, for example, a flat or circular sample, and has a double spiral structure using a hot disk method thermal property measuring device. A nickel foil sensor can be sandwiched between two samples, and the sensor can generate constant heat with constant power and can be calculated from the temperature rise of the sensor.

  The thermal diffusivity in the surface direction and the thickness direction of the high thermal conductive resin molding of the present invention is, for example, heated by a laser or light from the surface using a flash thermal diffusivity measuring device with a flat sample, It is possible to calculate the temperature by the method of measuring the temperature rise change on the back surface at a location slightly away from the back surface and the heated portion in the surface direction. In order to keep the sample surface temperature rise during measurement low, it is preferable to use a xenon flash thermal diffusivity measuring device for the measurement. When comparing the thermal diffusivity in the plane direction and the thickness direction measured by such a method, the thermal diffusivity measured in the plane direction of the molded body is twice the thermal diffusivity measured in the thickness direction of the molded body. With the above, for example, when the molded body is applied to an external housing or the like of a portable electronic device or the like, heat generated inside can be efficiently dispersed in the surface direction. This is defined as "high thermal diffusion anisotropy in the plane direction". The thermal diffusivity measured in the surface direction of the molded body is preferably 2.5 times or more, more preferably 3 times or more, and further preferably 4 times the thermal diffusivity measured in the thickness direction of the molded body. Above, most preferably 5 times or more.

Furthermore, in order to transfer the heat generated inside a portable electronic device or the like well to the outside, it is necessary to increase the absolute value of the thermal diffusivity of the molded body itself, and the heat measured in the surface direction of the molded body. The value of diffusivity needs to be 0.5 mm ² / sec or more. Thermal diffusivity measured in the surface direction of the molded body is preferably 0.75 mm ² / sec or more, more preferably 1.0 mm ² / sec or more, more preferably 1.5 mm ² / sec or more, and most preferably 2 0.0 mm ² / sec or more.

Since the high thermal conductive resin molding of the present invention can achieve both electrical insulation and high thermal conductivity, metal can be used because insulation is necessary while conventionally requiring high thermal conductivity. It can be used particularly useful for applications that did not exist. The surface electrical resistance value of the molded body measured by the two-terminal method according to ASTM D-257 needs to be 10 ¹⁰ Ω or more, preferably 10 ¹¹ Ω or more, more preferably 10 ¹² Ω or more, and most preferably Is 10 ¹³ Ω or more.

  Such a molded body can be molded by various thermoplastic resin molding methods such as injection molding, extrusion molding, press molding, blow molding, etc., but the molded body has a high shear rate that the resin composition receives during molding. It is preferable that the molded body is molded by an injection molding method because it can easily impart thermal diffusion anisotropy, has a short molding cycle and is excellent in productivity. The injection molding method is a method in which a mold is attached to an injection molding machine, a resin composition melt-plasticized by the molding machine is injected into the mold at a high speed, and the resin composition is cooled and solidified to have a predetermined purpose. This is a molding method of shaping into a shape and taking it out. There are no particular limitations on the molding machine and mold used at this time, and it is preferable to use a mold designed to obtain a molded body having a predetermined target shape. In addition, since a molded body having anisotropy in thermal diffusion is continuously obtained and productivity is high, a molded body molded by an extrusion molding method is also preferable.

  The molded body thus obtained is in various forms such as a resin film, a resin sheet, and a resin molded body, and an electronic material, a magnetic material, a catalyst material, a structural material, an optical material, a medical material, an automobile material, and an architectural material. It can be widely used for various applications such as materials. Since the general plastic injection molding machine currently widely used can be used for the highly heat conductive resin molding obtained by this invention, acquisition of the molding which has a complicated shape is also easy. The thermoplastic resin composition used for the high thermal conductive resin molding of the present invention has excellent properties such as good moldability and high thermal conductivity, and is a portable electronic device such as a mobile phone having a heat source inside. As a resin for molding casings of equipment, displays, computers, etc., and because it has excellent characteristics such as high light resistance, high whiteness, and high reflectance, it is used as a resin for molding lighting fixtures such as bulb sockets and arc tube holders. Is very useful.

  The high thermal conductive resin molded product of the present invention can be suitably used for home appliances, OA equipment parts, AV equipment parts, automotive interior / exterior parts, injection-molded bodies such as light bulb shaped lighting, and the like. In particular, it can be suitably used as an exterior material in home appliances and office automation equipment that generate a lot of heat. In addition, in an electronic device having a heat source inside but difficult to forcibly cool by a fan or the like, it is preferably used as an exterior material of these devices in order to dissipate heat generated inside to the outside. Furthermore, it can be suitably used as a lighting fixture member that is required to have a white color and a high reflectance and requires a long shape like a fluorescent lamp.

  Among these, as preferred devices, small or portable electronic devices such as portable computers such as notebook computers, PDAs, cellular phones, portable game machines, portable music players, portable TV / video devices, portable video cameras, etc. The thermoplastic resin composition used for the highly thermally conductive resin molded product of the present invention is very useful as the resin composition for the casing, housing, and exterior material.

  It can also be used very effectively as various materials for battery peripherals in automobiles, trains, etc., for portable batteries of household electrical appliances, for power distribution parts such as breakers, and for sealing motors.

  The high thermal conductive resin molded body of the present invention has better impact resistance and surface properties than the conventionally well-known molded body, and has useful properties for parts or casings in the above applications. is there.

  That is, such a molded body can be used as a heat countermeasure material in various situations such as in the electric / electronic industry field and the automobile field, and is industrially useful.

  Next, the present invention will be described in more detail based on examples, but the present invention is not limited only to such examples.

[Production Example 1]
After mixing 53 parts by weight of orthoboric acid, 43 parts by weight of melamine and 4 parts by weight of lithium nitrate with a Henschel mixer, 200 parts by weight of pure water was added, stirred at 80 ° C. for 8 hours, filtered, and dried at 150 ° C. for 1 hour. Dried . The obtained compound was heated at 900 ° C. for 1 hour in a nitrogen atmosphere, and further fired and crystallized at 1800 ° C. in a nitrogen atmosphere. The obtained fired product was pulverized to obtain a scale-shaped hexagonal boron nitride powder (BN-1). The number average particle diameter of the obtained powder was 48 μm, the whiteness was 92, the graphitization index was 1.0, and the tap density was 0.77 g / cm ³ . Moreover, as a result of solidifying this powder independently and measuring the thermal conductivity, the thermal conductivity was 300 W / mK and it was electrically insulating.

[Production Example 2]
After mixing 50 parts by weight of orthoboric acid, 40 parts by weight of melamine and 10 parts by weight of calcium carbonate with a Henschel mixer, 200 parts by weight of pure water was added, stirred at 80 ° C. for 8 hours, filtered, and dried at 150 ° C. for 1 hour. Dried . The obtained compound was heated at 900 ° C. for 1 hour in a nitrogen atmosphere, and further fired and crystallized at 2000 ° C. in a nitrogen atmosphere. The obtained calcined product was pulverized and then washed with an aqueous nitric acid solution to remove the calcium carbonate component and dried at 150 ° C. to obtain a scale-shaped hexagonal boron nitride powder (BN-2). The number average particle diameter of the obtained powder was 19 μm, the whiteness was 90, the graphitization index was 1.3, and the tap density was 0.88 g / cm ³ . Moreover, as a result of solidifying this powder independently and measuring the thermal conductivity, the thermal conductivity was 100 W / mK and it was electrically insulating.

(Example 1)
A mixture of 100 parts by weight of a polyethylene terephthalate resin (PBKII manufactured by Mitsubishi Chemical Corporation) and 0.2 parts by weight of a phenol-based stabilizer (AO-60 manufactured by ADEKA Corporation) was prepared (raw material 1). Separately, 100 parts by weight of flaky hexagonal boron nitride powder (BN-1), 50 parts by weight of glass fiber (FIL-1), 1 part by weight of epoxy silane coupling agent (KBM-303 manufactured by Shin-Etsu Chemical Co., Ltd.) Then, 5 parts by weight of ethanol was mixed with a super floater and stirred for 5 minutes, and then dried at 80 ° C. for 4 hours (raw material 2). Raw material 1 and raw material 2 are set in separate weight feeders and mixed so that the volume ratio of (A) / (B) is 55/30. It put in from a hopper provided near the screw root of the extruder TEX44XCT. The set temperature was 250 ° C. in the vicinity of the raw material supply port, the set temperature was sequentially increased toward the screw tip, and the screw tip temperature was set at 280 ° C. Sample pellets for injection molding were obtained under these conditions. The obtained pellets were dried at 140 ° C. for 4 hours and then passed through a pin gate installed with a gate size of 0.8 mmφ at the center of the flat surface of a 75t injection molding machine IS-75E-2A manufactured by Toshiba Machine Co., Ltd. A flat plate-shaped test piece of × 80 mm × thickness 1.1 mm was molded and subjected to evaluation of whiteness, light resistance, reflectance, thermal diffusivity and its anisotropy, and electrical insulation. In addition, a test piece having a thickness of 6.4 mm × 21 mmφ was formed through a gate having a gate diameter of 2 mm from the side of the formed body, and subjected to measurement of thermal conductivity as the formed body.

(Examples 2-6, Comparative Examples 1-7)
Except having changed the kind and quantity of a compounding raw material as shown in Table 1, it carried out similarly to Example 1, and obtained the molded object.
The raw materials used in Examples and Comparative Examples are as follows.

<Other inorganic compounds>
(BN-3): Scale-shaped hexagonal boron nitride powder (GP manufactured by Denki Kagaku Kogyo Co., Ltd., thermal conductivity 60 W / m · K alone, number average particle size 8 μm, whiteness 92, graphitization index 1. 3. Electrical insulation, volume resistivity 10 ¹⁴ Ω · cm, tap density 0.50 g / cm ³ ).
(BN-4): Aggregated hexagonal boron nitride powder obtained by agglomeration of scale-shaped hexagonal boron nitride powder (NW150 manufactured by National Nitride Technologies Co., Ltd., single unit thermal conductivity 60 W / m · K, number Average particle size 150 μm, whiteness 78, graphitization index 12, electrical insulation, volume resistivity 10 ¹⁴ Ω · cm, tap density 0.80 g / cm ³ ).
(BN-5): Turbulent layered boron nitride powder (manufactured by Yingkou Boda Fine Chemical Co., Ltd., single body thermal conductivity 25 W / m · K, number average particle size 0.8 μm, whiteness 75, graphitization index 4 0.7, electrical insulation, volume resistivity 10 ¹⁶ Ω · cm, tap density 0.20 g / cm ³ ).
(FIL-1): Glass fiber (T187H / PL manufactured by Nippon Electric Glass Co., Ltd., single body thermal conductivity 1.0 W / m · K, fiber diameter 13 μm, number average fiber length 3.0 mm, electrical insulation, Volume resistivity 10 ¹⁵ Ω · cm)
(FIL-2): Titanium oxide (CR-60 manufactured by Ishihara Sangyo Co., Ltd., thermal conductivity 5.0 W / m · K alone, average particle size 0.21 μm, electrical insulation, volume resistivity 10 ¹⁴ Ω · cm)
(FIL-3): natural scaly graphite powder (BF-50A manufactured by Chuetsu Graphite Co., Ltd., single body thermal conductivity 250 W / m · K, number average particle size 53 μm, conductivity, tap density 0.64 g / cm ³ )

<Thermoplastic polyester resin (A)>
(PES-1): Polyethylene terephthalate resin (PBKII manufactured by Mitsubishi Chemical Corporation)
(PC-1): Polycarbonate resin (Taflon A-2200 manufactured by Idemitsu Kosan Co., Ltd.)
(PPS-1): Polyphenylene sulfide resin (M3910 manufactured by Toray Industries, Inc.)

<Other compounds>
(FR-1): Brominated composite flame retardant; Brominated phthalimide flame retardant (SAYTEX BT-93W manufactured by Albemarle Corporation) / antimony trioxide (PATOX-p manufactured by Nippon Seiko Co., Ltd.) = 82/18 (weight ratio) ) Composite (FR-2): Phosphorus flame retardant (Exolit OP-935 manufactured by Clariant Japan)

[Number average particle diameter of boron nitride powder]
A 100 ml beaker was charged with 15 ml of a 20% by weight aqueous solution of sodium hexametaphosphate, and 60 mg of boron nitride powder was added to this aqueous solution, followed by dispersion treatment for 40 minutes with an ultrasonic disperser. With the obtained dispersion, the number average particle size was measured using a laser diffraction / scattering particle size distribution analyzer LA-950 manufactured by Horiba, Ltd.

[Whiteness W of boron nitride powder]
A quartz glass sample cell having a diameter of 30 mm and a height of 13 mm is filled with boron nitride powder, and color brightness (L), hue, saturation (by using a colorimetric color difference meter SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd.) a, b) were measured, and the whiteness W was calculated by the equation (1).

[Graphitization index GI of boron nitride powder]
A wide angle X-ray diffraction measurement of boron nitride powder was performed with Cu · Kα X-rays using a Spectraly Co., Ltd. PANalytical X'Pert Pro XRD measuring device. From the measured values obtained, the areas of (100), (101), and (102) found at 2θ = 41 °, 44 °, and 50 ° were measured, and the graphitization index GI was calculated from the equation (2). .

[Tap density of boron nitride powder]
Using a powder tester PT-E manufactured by Hosokawa Micron Co., Ltd., filling the boron nitride powder into a special container of 100 cm3, tapping time is 180 seconds, tapping frequency is 180 times, and tapping is performed under the conditions of 18 mm tap lift. The tap density was measured.

[Whiteness of molded product]
The lightness (L), hue, and saturation (a, b) of the color of the molded product are measured using a colorimetric color difference meter SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd., and the whiteness is calculated by the equation (1). did.

[Light resistance of molded products]
A flat plate sample was placed at a distance of 10 cm from a 400 W mercury lamp placed in a constant temperature bath at a set temperature of 120 ° C., and the mercury lamp irradiation was continued for 7 days. The color tone (L, a, b) of the test piece before and after irradiation was measured using a colorimetric color difference meter SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd., and the color difference ΔE was calculated by the equation (3).

[Reflectance of molded product]
The reflectance of the molded product was measured using an ultraviolet-visible spectrophotometer V-650 manufactured by JASCO Corporation. The specular reflection was measured by applying light at an incident angle of 7 °. The value of the total light reflectance at a wavelength of 550 nm is described as a representative value.

[Thermal conductivity as molded body]
Using two test pieces having a thickness of 6.4 mm × 21 mmφ, the thermal conductivity as a molded body was measured with a hot disk method thermal property measuring apparatus TPA-501 manufactured by Kyoto Electronics Industry Co., Ltd.

[Thermal diffusivity of molded article and its anisotropy]
The obtained molded body having a thickness of 1.1 mm was cut out to prepare a disk-shaped sample of 25.4 mmφ. After applying and drying a laser light absorbing spray (Fine Chemical Japan Co., Ltd. Black Guard Spray FC-153) on the sample surface, the thermal diffusivity in the thickness direction and in the surface direction is measured using a NETZSCH Xe flash analyzer LFA447 Nanoflash. did.
From the obtained thermal diffusivity, the thermal diffusion anisotropy was calculated by the following equation (4).
(Anisotropy of thermal diffusion) = (thermal diffusivity in the plane direction) / (thermal diffusivity in the thickness direction) (4)

[Electrical insulation]
Using a flat plate, the surface electrical resistance value was measured by a two-terminal method according to ASTM D-257.

The respective formulations and results are shown in Table 1. From Table 1, the thermoplastic resin composition used in the molded product of the present invention is a resin composition having a high reflectivity in molding fluidity and a high thermal conductivity compared to a composition outside the range of the composition. I know that there is. Especially Example 2 and Example 4 which mix | blended FIL-2 were favorable in whiteness, light resistance, and a reflectance.
In the table, “impossible” was indicated for those that could not be measured because the molding process was difficult. Since Comparative Example 6 was ocher and Comparative Example 7 was black, some tests were not performed.

  Regarding the formulation of Example 1, the heat radiation performance was confirmed by injection molding (Example 2-1) into a heat sink shape as shown in FIG.

  The measurement was performed by installing a heat sink on the heater and a heat insulating material under the heater as shown in FIG. 2 and inserting a thermistor between the heater and the heat insulating material. The heater generates heat in 1.2W and 0.4W. It was confirmed that it was in a steady state by leaving it at room temperature for 25 hours under natural convection for one hour.

  Similarly, a melt-pressed sample of the same shape (Example 2-2), a sample (Comparative Example 2-1) of polyethylene (Hi-Zex 3000B manufactured by Prime Polymer Co., Ltd.), an aluminum heat sink (LSI Cooler Co., Ltd.) 12F31L30) (Comparative Example 2-2) was used. The aluminum heat sink of Comparative Example 2-2 was blackened on the surface to improve the emissivity.

  The measurement results are shown in Table 2. From Table 2, it can be seen that when the molded body of the present invention is used, performance comparable to that of an aluminum heat sink is exhibited, and in particular, the performance is further improved by injection molding.

Fig. 2 1 Heat sink Fig. 2 Heating element Fig. 2 3 Heat insulator

Claims (5)

A high heat conductive resin molded body for a heat sink partially or wholly formed of a high heat conductive resin composition, wherein the high heat conductive resin composition is a thermoplastic polyester resin (A) having a number average particle size. It contains at least a scale-shaped hexagonal boron nitride powder (B) having a whiteness W of 90 or more and a graphitization index GI of 2.0 or less, and glass fiber , and the volume ratio of (A) / (B) is 15 μm or more. obtained from 85 / 15-25 / 75 resin composition is in the range of, and is molded by injection molding, whiteness 80 or more and Ri der total light reflectance than 50%, 120 ° C. atmosphere in 400W mercury lamp upon 7 days continuously irradiated from a distance of 10cm the color difference before and after irradiation △ E heat sink for highly thermally conductive resin formed body, characterized in der Rukoto 10 or less.   The heat-conductive resin molded body for heat sink according to claim 1, wherein the number average particle diameter of the scale-shaped hexagonal boron nitride powder (B) is 30 µm or more. The highly heat conductive resin molded body for a heat sink according to claim 1 or 2, wherein the tap density of the scale-shaped hexagonal boron nitride powder (B) is 0.6 g / cm ³ or more. The thermal diffusivity in the surface direction of the molded body is twice or more the thermal diffusivity in the thickness direction of the molded body, and the thermal diffusivity in the surface direction of the molded body is 0.5 mm ² / sec or more. The high heat conductive resin molding for heat sinks according to any one of claims 1 to 3 . The thermal conductivity of the formed features is not less 1W / m · K or more, and characterized in that further surface resistivity is 10 ¹¹ Omega above, heat sink according to any one of claims 1-4 High thermal conductive resin molding.