JP2016169279A - Thermally conductive polycarbonate resin composition and molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally conductive polycarbonate resin composition that has high thermal conductivity, has an excellent flexural modulus and has excellent lightness in weight, and a molding.SOLUTION: A thermally conductive polycarbonate resin composition has, based on polycarbonate resin (A) 100 pts.mass, pitch-based carbon fiber (B) 10-100 pts.mass and PAN-based carbon fiber (C) 10-100 pts.mass, where a mass ratio between (B) and (C) contents, ((B)/(C)), is 1 or more.SELECTED DRAWING: None

Description

  The present invention relates to a heat conductive polycarbonate resin composition and a molded article, and more particularly to a heat conductive polycarbonate resin composition and a molded article having excellent bending elastic modulus and light weight and high heat conductivity.

  Polycarbonate resin is excellent in impact resistance, heat resistance, electrical insulation, dimensional stability, etc., and has a good balance of these characteristics. Therefore, electrical and electronic equipment parts, OA equipment parts, precision equipment parts, vehicle parts Widely used in such fields.

  However, since the polycarbonate resin has a high electric resistivity and is easily charged, it may cause various troubles due to static electricity. Moreover, in the above-mentioned field, most devices are equipped with components that generate heat. However, in recent years, there has been a strong demand for higher functionality and higher speed of devices. On the other hand, the amount of heat generated from the internal elements of the device tends to increase as the power consumption per component increases due to high-speed processing and large capacity. In situations where heat dissipation is not sufficient, there is concern about thermal damage to internal elements and problems that cause local high temperatures on the surface of parts (housing) that hold the elements. There is a need for a polycarbonate resin material that is one and exhibits higher thermal conductivity.

  As a method of imparting thermal conductivity to a polycarbonate resin material, a method of blending various thermal conductive fillers is known, and Patent Documents 1 to 6 show polycarbonate resin compositions having good thermal conductivity. ing. However, these polycarbonate resin compositions can exhibit good thermal conductivity, but have the disadvantage that the rigidity is deteriorated, and are excellent in thermal conductivity and have high rigidity. A resin composition is desired.

  In addition, there is a remarkable trend in miniaturization and weight reduction of electrical and electronic equipment and precision equipment in recent years. For example, electrical and electronic equipment, parts that hold internal elements of precision equipment (outer shell parts and housings), for example, Camera parts, especially parts for holding image processing elements in digital cameras (frames, housings), etc., have a high rigidity (bending elastic modulus) while minimizing the density of the materials themselves. There is a strong demand for polycarbonate resin materials that are required and have excellent fluidity for thinning, high thermal conductivity for heat dissipation, and high self-tap strength.

JP 2007-16093 A JP 2007-238917 A JP 2008-127554 A JP 2008-163270 A JP 2009-161582 A JP 2011-16936 A

  In view of the above, an object (issue) of the present invention is a polycarbonate having high thermal conductivity, high rigidity (flexural modulus), excellent lightness, and excellent fluidity and self-tapping strength. The object is to provide a resin composition and a molded article.

As a result of intensive studies to achieve the above-mentioned problems, the inventor has specified a specific amount of pitch-based carbon fiber and PAN-based carbon fiber and specified a ratio of the content of pitch-based carbon fiber and PAN-based carbon fiber. It has been found that a polycarbonate resin composition contained at a mass ratio of the above solves the above problems, and has led to the completion of the present invention.
The present invention provides the following thermally conductive polycarbonate resin composition and molded article.

[1] 10 to 100 parts by mass of pitch-based carbon fiber (B) and 10 to 100 parts by mass of PAN-based carbon fiber (C) with respect to 100 parts by mass of polycarbonate resin (A), (B) and (C) The heat conductive polycarbonate resin composition characterized by having a mass ratio ((B) / (C)) of 1 or more.
[2] The heat conductive polycarbonate resin composition according to [1], further containing 5 to 30 parts by mass of the acrylonitrile-styrene copolymer (D) with respect to 100 parts by mass of the polycarbonate resin (A).
[3] A molded product obtained by molding the thermally conductive polycarbonate resin composition according to [1] or [2].

  According to the heat conductive polycarbonate resin composition of the present invention, the heat conductive polycarbonate resin composition having high heat conductivity, excellent flexural modulus and light weight, and excellent fluidity and self-tap strength. And a molded article can be provided.

It is the schematic of the spiral long resin molded object created by the measurement of the spiral flow length in an Example.

Hereinafter, although an embodiment, an example thing, etc. are shown and explained in detail about the present invention, the present invention is limited to an embodiment, an example, etc. shown below and is not interpreted.
In the present specification, unless otherwise specified, “to” is used in a sense that includes numerical values described before and after it as a lower limit value and an upper limit value.

  The thermally conductive polycarbonate resin composition of the present invention contains 10 to 100 parts by mass of pitch-based carbon fibers (B) and 10 to 100 parts by mass of PAN-based carbon fibers (C), and contains (B) and (C). The mass ratio of the quantity ((B) / (C)) is 1 or more.

[Polycarbonate resin (A)]
There is no restriction | limiting in the kind of polycarbonate resin (A) used in this invention, A polycarbonate resin may use 1 type and may use 2 or more types together by arbitrary combinations and arbitrary ratios.
The polycarbonate resin is a polymer having a basic structure having a carbonic acid bond represented by the formula: — [— O—X—O—C (═O) —] —. In the formula, X is generally a hydrocarbon, but for imparting various properties, X into which a hetero atom or a hetero bond is introduced may be used.
The polycarbonate resin can be classified into an aromatic polycarbonate resin in which carbon directly bonded to a carbonic acid bond is aromatic carbon and an aliphatic polycarbonate resin in which aliphatic carbon is aliphatic carbon, either of which can be used. Of these, aromatic polycarbonate resins are preferred from the viewpoints of heat resistance, mechanical properties, electrical characteristics, and the like.

  Although there is no restriction | limiting in the specific kind of polycarbonate resin, For example, the polycarbonate polymer formed by making a dihydroxy compound and a carbonate precursor react is mentioned. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Further, a method of reacting carbon dioxide with a cyclic ether using a carbonate precursor may be used. The polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a homopolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. In general, such a polycarbonate polymer is a thermoplastic resin.

  Among monomers used as raw materials for aromatic polycarbonate resins, examples of aromatic dihydroxy compounds include:

Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie, resorcinol), 1,4-dihydroxybenzene;
Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl;

2,2′-dihydroxy-1,1′-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, , 7-dihydroxynaphthalene, dihydroxynaphthalene such as 2,7-dihydroxynaphthalene;

2,2′-dihydroxydiphenyl ether, 3,3′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) Dihydroxy diaryl ethers such as benzene and 1,3-bis (4-hydroxyphenoxy) benzene;

2,2-bis (4-hydroxyphenyl) propane (ie, bisphenol A),
1,1-bis (4-hydroxyphenyl) propane,
2,2-bis (3-methyl-4-hydroxyphenyl) propane,
2,2-bis (3-methoxy-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-methoxy-4-hydroxyphenyl) propane,
1,1-bis (3-tert-butyl-4-hydroxyphenyl) propane,
2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane,
2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-cyclohexyl-4-hydroxyphenyl) propane,
α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene,
1,3-bis [2- (4-hydroxyphenyl) -2-propyl] benzene,
Bis (4-hydroxyphenyl) methane,
Bis (4-hydroxyphenyl) cyclohexylmethane,
Bis (4-hydroxyphenyl) phenylmethane,
Bis (4-hydroxyphenyl) (4-propenylphenyl) methane,
Bis (4-hydroxyphenyl) diphenylmethane,
Bis (4-hydroxyphenyl) naphthylmethane,
1,1-bis (4-hydroxyphenyl) ethane,
1,1-bis (4-hydroxyphenyl) -1-phenylethane,
1,1-bis (4-hydroxyphenyl) -1-naphthylethane,
1,1-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) pentane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
1,1-bis (4-hydroxyphenyl) octane,
2,2-bis (4-hydroxyphenyl) octane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
4,4-bis (4-hydroxyphenyl) heptane,
2,2-bis (4-hydroxyphenyl) nonane,
1,1-bis (4-hydroxyphenyl) decane,
1,1-bis (4-hydroxyphenyl) dodecane,
Bis (hydroxyaryl) alkanes such as;

1,1-bis (4-hydroxyphenyl) cyclopentane,
1,1-bis (4-hydroxyphenyl) cyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,4-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,5-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxy-3,5-dimethylphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-propyl-5-methylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -4-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -3-phenylcyclohexane,
1,1-bis (4-hydroxyphenyl) -4-phenylcyclohexane,
Bis (hydroxyaryl) cycloalkanes such as;

9,9-bis (4-hydroxyphenyl) fluorene,
Cardio structure-containing bisphenols such as 9,9-bis (4-hydroxy-3-methylphenyl) fluorene;

4,4′-dihydroxydiphenyl sulfide,
Dihydroxydiaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide;

Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide;

4,4′-dihydroxydiphenyl sulfone,
Dihydroxydiaryl sulfones such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone;
Etc.

Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are particularly preferable, and 2,2-bis (4-hydroxyphenyl) propane (especially from the viewpoint of impact resistance and heat resistance). That is, bisphenol A) is preferred.
In addition, 1 type may be used for an aromatic dihydroxy compound and it may use 2 or more types together by arbitrary combinations and a ratio.

In addition, when an example of a monomer that is a raw material of the aliphatic polycarbonate resin is given,
Ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1,3-diol, 2-methyl-2-propylpropane-1,3- Alkanediols such as diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, decane-1,10-diol;

  Cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4- (2-hydroxyethyl) cyclohexanol, 2,2,4, Cycloalkanediols such as 4-tetramethyl-cyclobutane-1,3-diol;

  Glycols such as ethylene glycol, 2,2'-oxydiethanol (ie, diethylene glycol), triethylene glycol, propylene glycol, spiro glycol and the like;

  1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1,4-benzenediethanol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis ( 2-hydroxyethoxy) benzene, 2,3-bis (hydroxymethyl) naphthalene, 1,6-bis (hydroxyethoxy) naphthalene, 4,4′-biphenyldimethanol, 4,4′-biphenyldiethanol, 1,4- Aralkyl diols such as bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2-hydroxyethyl) ether;

  1,2-epoxyethane (ie ethylene oxide), 1,2-epoxypropane (ie propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, 1-methyl And cyclic ethers such as -1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane;

  Among the monomers used as the raw material for the polycarbonate resin, carbonyl halides, carbonate esters and the like are used as examples of the carbonate precursor. In addition, 1 type may be used for a carbonate precursor and it may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of carbonyl halides include phosgene; haloformates such as bischloroformate of dihydroxy compounds and monochloroformate of dihydroxy compounds.

  Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate bodies of dihydroxy compounds, monocarbonate bodies of dihydroxy compounds, and cyclic carbonates. And carbonate bodies of dihydroxy compounds such as

-Manufacturing method of polycarbonate resin The manufacturing method of polycarbonate resin is not specifically limited, Arbitrary methods are employable. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer.
Hereinafter, a particularly preferable one of these methods will be described in detail.

.. Interfacial polymerization method First, the case where a polycarbonate resin is produced by the interfacial polymerization method will be described.
In the interfacial polymerization method, a dihydroxy compound and a carbonate precursor (preferably phosgene) are reacted in the presence of an organic solvent inert to the reaction and an aqueous alkaline solution, usually at a pH of 9 or higher. Polycarbonate resin is obtained by interfacial polymerization in the presence. In the reaction system, a molecular weight adjusting agent (terminal terminator) may be present as necessary, or an antioxidant may be present to prevent the oxidation of the dihydroxy compound.

  The dihydroxy compound and the carbonate precursor are as described above. Of the carbonate precursors, phosgene is preferably used, and a method using phosgene is particularly called a phosgene method.

  Examples of the organic solvent inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene and dichlorobenzene; aromatic hydrocarbons such as benzene, toluene and xylene; It is done. In addition, 1 type may be used for an organic solvent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the alkali compound contained in the alkaline aqueous solution include alkali metal compounds and alkaline earth metal compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and sodium hydrogen carbonate, among which sodium hydroxide and water Potassium oxide is preferred. In addition, 1 type may be used for an alkali compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Although there is no restriction | limiting in the density | concentration of the alkali compound in alkaline aqueous solution, Usually, in order to control pH in the alkaline aqueous solution of reaction to 10-12, it is used at 5-10 mass%. For example, when phosgene is blown, the molar ratio of the bisphenol compound and the alkali compound is usually 1: 1.9 or more in order to control the pH of the aqueous phase to be 10 to 12, preferably 10 to 11. Among these, it is preferable that the ratio is 1: 2.0 or more, usually 1: 3.2 or less, and more preferably 1: 2.5 or less.

  Examples of the polymerization catalyst include aliphatic tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, and trihexylamine; alicyclic rings such as N, N′-dimethylcyclohexylamine and N, N′-diethylcyclohexylamine. Formula tertiary amines; aromatic tertiary amines such as N, N′-dimethylaniline and N, N′-diethylaniline; quaternary ammonium salts such as trimethylbenzylammonium chloride, tetramethylammonium chloride, triethylbenzylammonium chloride, etc. Pyridine; guanidine salt; and the like. In addition, 1 type may be used for a polymerization catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the molecular weight regulator include aromatic phenols having a monohydric phenolic hydroxyl group; aliphatic alcohols such as methanol and butanol; mercaptans; phthalimides and the like. Of these, aromatic phenols are preferred. Specific examples of such aromatic phenols include alkyl groups such as m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, p-tert-butylphenol, and p-long chain alkyl-substituted phenol. Examples thereof include substituted phenols; vinyl group-containing phenols such as isopropanyl phenol; epoxy group-containing phenols; carboxyl group-containing phenols such as o-hydroxybenzoic acid and 2-methyl-6-hydroxyphenylacetic acid; In addition, a molecular weight regulator may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The usage-amount of a molecular weight regulator is 0.5 mol or more normally with respect to 100 mol of dihydroxy compounds, Preferably it is 1 mol or more, and is 50 mol or less normally, Preferably it is 30 mol or less. By making the usage-amount of a molecular weight modifier into this range, the thermal stability and hydrolysis resistance of a resin composition can be improved.

In the reaction, the order of mixing the reaction substrate, reaction medium, catalyst, additive and the like is arbitrary as long as a desired polycarbonate resin is obtained, and an appropriate order may be arbitrarily set. For example, when phosgene is used as the carbonate precursor, the molecular weight regulator can be mixed at any time as long as it is between the reaction (phosgenation) of the dihydroxy compound and phosgene and the start of the polymerization reaction.
In addition, reaction temperature is 0-40 degreeC normally, and reaction time is normally several minutes (for example, 10 minutes)-several hours (for example, 6 hours).

-Melt transesterification method Next, the case where a polycarbonate resin is manufactured by the melt transesterification method is demonstrated.
In the melt transesterification method, for example, a transesterification reaction between a carbonic acid diester and a dihydroxy compound is performed.

The dihydroxy compound is as described above.
On the other hand, examples of the carbonic acid diester include dialkyl carbonate compounds such as dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate; diphenyl carbonate; substituted diphenyl carbonate such as ditolyl carbonate, and the like. Among these, diphenyl carbonate and substituted diphenyl carbonate are preferable, and diphenyl carbonate is more preferable. In addition, carbonic acid diester may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The ratio of the dihydroxy compound and the carbonic acid diester is arbitrary as long as the desired polycarbonate resin is obtained, but it is preferable to use an equimolar amount or more of the carbonic acid diester with respect to 1 mol of the dihydroxy compound, and above all, 1.01 mol or more is used. It is more preferable. The upper limit is usually 1.30 mol or less. By setting it as such a range, the amount of terminal hydroxyl groups can be adjusted to a suitable range.

  In the polycarbonate resin, the amount of terminal hydroxyl groups tends to have a great influence on thermal stability, hydrolysis stability, color tone and the like. For this reason, you may adjust the amount of terminal hydroxyl groups as needed by a well-known arbitrary method. In the transesterification reaction, a polycarbonate resin in which the amount of terminal hydroxyl groups is adjusted can be usually obtained by adjusting the mixing ratio of the carbonic diester and the aromatic dihydroxy compound; the degree of vacuum during the transesterification reaction, and the like. In addition, the molecular weight of the polycarbonate resin usually obtained can also be adjusted by this operation.

When adjusting the amount of terminal hydroxyl groups by adjusting the mixing ratio of the carbonic acid diester and the dihydroxy compound, the mixing ratio is as described above.
Further, as a more aggressive adjustment method, there may be mentioned a method in which a terminal terminator is mixed separately during the reaction. Examples of the terminal terminator at this time include monohydric phenols, monovalent carboxylic acids, carbonic acid diesters, and the like. In addition, 1 type may be used for a terminal terminator and it may use 2 or more types together by arbitrary combinations and a ratio.

  When producing a polycarbonate resin by the melt transesterification method, a transesterification catalyst is usually used. Any transesterification catalyst can be used. Among them, it is preferable to use, for example, an alkali metal compound and / or an alkaline earth metal compound. In addition, auxiliary compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds may be used in combination. In addition, 1 type may be used for a transesterification catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  In the melt transesterification method, the reaction temperature is usually 100 to 320 ° C. The pressure during the reaction is usually a reduced pressure condition of 2 mmHg or less. As a specific operation, a melt polycondensation reaction may be performed under the above-mentioned conditions while removing a by-product such as an aromatic hydroxy compound.

  The melt polycondensation reaction can be performed by either a batch method or a continuous method. When performing by a batch type, the order which mixes a reaction substrate, a reaction medium, a catalyst, an additive, etc. is arbitrary as long as a desired aromatic polycarbonate resin is obtained, What is necessary is just to set an appropriate order arbitrarily. However, considering the stability of the polycarbonate resin and the like, the melt polycondensation reaction is preferably carried out continuously.

  In the melt transesterification method, a catalyst deactivator may be used as necessary. As the catalyst deactivator, a compound that neutralizes the transesterification catalyst can be arbitrarily used. Examples thereof include sulfur-containing acidic compounds and derivatives thereof. In addition, 1 type may be used for a catalyst deactivator and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the catalyst deactivator used is usually 0.5 equivalents or more, preferably 1 equivalent or more, and usually 10 equivalents or less, relative to the alkali metal or alkaline earth metal contained in the transesterification catalyst. Preferably it is 5 equivalents or less. Furthermore, it is 1 ppm or more normally with respect to polycarbonate resin, and is 100 ppm or less normally, Preferably it is 20 ppm or less.

-Other matters regarding the polycarbonate resin (A) The molecular weight of the polycarbonate resin (A) may be appropriately selected and determined. The viscosity average molecular weight [Mv] is usually 10,000 or more, preferably 16000 or more, more preferably 17000 or more. More preferably, it is 18000 or more, and is usually 40000 or less, preferably 30000 or less.

The viscosity average molecular weight [Mv] is obtained by using methylene chloride as a solvent and obtaining an intrinsic viscosity [η] (unit: dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer. , Η = 1.23 × 10 ⁻⁴ Mv ^0.83 . The intrinsic viscosity [η] is a value calculated from the following equation by measuring the specific viscosity [η _sp ] at each solution concentration [C] (g / dl).

  The terminal hydroxyl group concentration of the polycarbonate resin (A) is arbitrary and may be appropriately selected and determined, but is usually 1000 ppm or less, preferably 800 ppm or less, more preferably 600 ppm or less. Thereby, the residence heat stability and color tone of polycarbonate resin can be improved more. In addition, the lower limit is usually 10 ppm or more, preferably 30 ppm or more, more preferably 40 ppm or more, particularly for polycarbonate resins produced by the melt transesterification method. Thereby, the fall of molecular weight can be suppressed and the mechanical characteristic of a resin composition can be improved more.

  In addition, the unit of a terminal hydroxyl group density | concentration represents the mass of the terminal hydroxyl group with respect to the mass of polycarbonate resin in ppm. The measurement method is colorimetric determination (method described in Macromol. Chem. 88 215 (1965)) by the titanium tetrachloride / acetic acid method.

  The polycarbonate resin is a polycarbonate resin alone (the polycarbonate resin alone is not limited to an embodiment containing only one type of polycarbonate resin, and is used in a sense including an embodiment containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights, for example. .), Or an alloy (mixture) of a polycarbonate resin and another thermoplastic resin may be used in combination. Further, for example, for the purpose of further improving flame retardancy and impact resistance, a polycarbonate resin is copolymerized with an oligomer or polymer having a siloxane structure; for the purpose of further improving thermal oxidation stability and flame retardancy A monomer, oligomer or polymer having a copolymer; a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; A copolymer with an oligomer or polymer having an olefin structure; a copolymer with a polyester resin oligomer or polymer for the purpose of improving chemical resistance; Good.

  In addition, the polycarbonate resin (A) may contain a polycarbonate oligomer in order to improve the appearance and fluidity of the molded product. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1500 or more, preferably 2000 or more, and is usually 9500 or less, preferably 9000 or less. Furthermore, the polycarbonate ligomer contained is preferably 30% by mass or less of the polycarbonate resin (A) (including the polycarbonate oligomer).

Further, the polycarbonate resin (A) may be not only a virgin raw material but also a polycarbonate resin regenerated from a used product (so-called material-recycled polycarbonate resin). Examples of the used products include: optical recording media such as optical disks; light guide plates; vehicle window glass, vehicle headlamp lenses, windshields and other vehicle transparent members; water bottles and other containers; eyeglass lenses; Examples include architectural members such as glass windows and corrugated sheets. Also, non-conforming products, pulverized products obtained from sprues, runners, etc., or pellets obtained by melting them can be used.
However, the regenerated polycarbonate resin is preferably 80% by mass or less, more preferably 50% by mass or less, among the polycarbonate resin (A). Recycled polycarbonate resin is likely to have undergone deterioration such as heat deterioration and aging deterioration, so when such polycarbonate resin is used more than the above range, hue and mechanical properties can be reduced. It is because there is sex.

[Carbon fiber]
The thermally conductive polycarbonate resin composition of the present invention contains a PAN-based carbon fiber (C) together with a pitch-based carbon fiber (B), and in this case, the pitch-based carbon fiber (B) and the PAN-based carbon fiber (C). By making the mass ratio ((B) / (C)) of the content of 1 or more, all of weight reduction, high rigidity, and high thermal conductivity can be achieved.

The raw material pitch of the pitch-based carbon fiber (B) can be produced from various raw materials such as petroleum and coal. The raw material pitch used here is not particularly limited as long as spinning is possible, but a pitch containing an optically anisotropic phase (mesophase) is preferable from the viewpoint of high conductivity. The PAN-based carbon fiber (C) is obtained by spinning and firing polyacrylonitrile (PAN) as a raw material.
In addition, in the heat conductive polycarbonate resin composition of this invention, carbon fiber derived from other raw materials, such as rayon type | system | group, can also be mix | blended other than carbon fibers other than pitch type and PAN type, for example.

The average fiber diameter of the pitch-based carbon fiber (B) is preferably 20 μm or less, and if it exceeds 20 μm, the balance between dimensional stability and impact resistance is lowered, which is not preferable. From the balance of fluidity, impact resistance, dimensional stability and appearance, it is more preferably 15 μm or less, further preferably 13 μm or less, particularly preferably 12 μm or less, preferably 5 μm or more, more preferably 8 μm or more, still more preferably. Is 9 μm or more.
The length of the pitch-based carbon fiber (B) (length as a raw material before kneading) is preferably 3 to 20 mm, more preferably 4 mm or more, further preferably 5 mm or more, more preferably 15 mm or less, The thickness is preferably 10 mm or less, particularly preferably 8 mm or less.
The average fiber length in the polycarbonate resin composition is preferably in the range of 0.1 to 2 mm from the viewpoint of the balance of thermal conductivity, rigidity, impact resistance, dimensional stability and appearance.

The average fiber diameter of the PAN-based carbon fiber (C) is preferably 15 μm or less, and exceeding 15 μm is not preferable because the balance between dimensional stability and impact resistance is lowered. From the balance of fluidity, impact resistance, dimensional stability and appearance, it is more preferably 13 μm or less, further preferably 10 μm or less, particularly preferably 9 μm or less, preferably 3 μm or more, more preferably 4 μm or more, even more preferably. Is preferably 5 μm or more, particularly preferably 6 μm or more.
The length of the PAN-based carbon fiber (C) (length as a raw material before kneading) is preferably 3 to 20 mm, more preferably 4 mm or more, further preferably 5 mm or more, more preferably 15 mm or less, The thickness is preferably 10 mm or less, particularly preferably 8 mm or less.
The average fiber length in the polycarbonate resin composition is preferably in the range of 0.1 to 2 mm from the viewpoint of the balance of thermal conductivity, rigidity, impact resistance, dimensional stability and appearance.

The pitch-based carbon fiber (B) and the PAN-based carbon fiber (C) are preferably subjected to surface treatment, and the tensile strength and bending strength as the resin composition are improved. Any commonly used surface treating agent can be used, and examples thereof include epoxy sizing agents, urethane sizing agents, epoxy-urentane sizing agents, polyamide sizing agents, and olefin sizing agents. Among these, epoxy-based, polyamide-based, and urethane-based materials are preferable because of their good dispersibility with respect to the polycarbonate resin.
The amount of the surface treatment agent is preferably in the range of 0.5 to 15 parts by mass with respect to 100 parts by mass of the pitch-based carbon fiber (B) or the PAN-based carbon fiber (C). More preferably, it is within the range.

  Content of the pitch-type carbon fiber (B) in the heat conductive polycarbonate resin composition of this invention is 10-100 mass parts with respect to 100 mass parts of polycarbonate resin (A). When the content of the carbon fiber (B) is less than 10 parts by mass, the thermal conductivity is insufficient. Conversely, when the content exceeds 100 parts by mass, the impact resistance and fluidity are insufficient. The content of the pitch-based carbon fiber (B) is preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and preferably 80 parts by mass or less, more preferably 65 parts by mass or less.

  Content of the PAN type carbon fiber (C) in the heat conductive polycarbonate resin composition of this invention is 10-100 mass parts with respect to 100 mass parts of polycarbonate resin (A). If the content of the PAN-based carbon fiber (C) is less than 10 parts by mass, the rigidity is insufficient, and if it exceeds 100 parts by mass, the impact resistance and fluidity are insufficient. The content of the PAN-based carbon fiber (C) is preferably 15 parts by mass or more, more preferably 20 parts by mass or more, preferably 80 parts by mass or less, more preferably 60 parts by mass or less, and further preferably 50 parts by mass. Part or less, particularly 40 parts by weight or less, particularly 30 parts by weight or less are preferred.

As described above, the mass ratio of the content of the pitch-based carbon fiber (B) and the PAN-based carbon fiber (C) is (B) / (C) and is 1.0 or more, preferably 1.1. More preferably, it is 1.2 or more, more preferably 1.25 or more, preferably 5 or less, more preferably 4 or less, further 3 or less, particularly preferably 2 or less. By setting the mass ratio of the content of pitch-based carbon fiber (B) and PAN-based carbon fiber (C) within the above range, characteristics such as thermal conductivity, rigidity, elastic modulus, impact resistance, and fluidity during molding can be obtained. It becomes possible to improve in a balanced manner.
The total content of the pitch-based carbon fiber (B) and the PAN-based carbon fiber (C) is preferably 30 parts by mass or more, more preferably 35 parts by mass or more, with respect to 100 parts by mass of the polycarbonate resin (A). More preferably, it is 40 parts by mass or more, preferably 125 parts by mass or less, more preferably 100 parts by mass or less, still more preferably 80 parts by mass or less, and particularly preferably 70 parts by mass or less.

[Acrylonitrile-styrene copolymer (D)]
The thermally conductive polycarbonate resin composition of the present invention preferably contains an acrylonitrile-styrene copolymer (D). By containing the acrylonitrile-styrene copolymer (D), the fluidity of the polycarbonate resin composition of the present invention can be further improved and the self-tapping property can be improved, which is preferable. The acrylonitrile-styrene copolymer (D) refers to a copolymer of acrylonitrile and one or more styrene monomers.
The method for producing the acrylonitrile-styrene copolymer is not particularly limited, and a known method can be employed. For example, methods such as bulk polymerization, solution polymerization, suspension polymerization, bulk suspension polymerization, and emulsion polymerization are used. It can also be obtained by blending separately polymerized or copolymerized resins.
As the styrene monomer constituting the acrylonitrile-styrene copolymer (D), styrene, α-methylstyrene, p-methylstyrene, bromostyrene and the like are preferable, and styrene and / or α-methylstyrene is more preferable. .

The styrene monomer content in the acrylonitrile-styrene copolymer (D) is preferably 50 to 95% by mass, and more preferably 65 to 92% by mass.
The melt flow rate (MFR) reflecting the molecular weight of the acrylonitrile-styrene copolymer (D) is preferably 5 to 50 g / 10 min at 220 ° C. and a load of 10 kg, more preferably 10 to 30 g / 10 min.

  As the acrylonitrile-styrene copolymer (D), those commercially available as acrylonitrile styrene copolymer (AS resin) or acrylonitrile styrene copolymer (SAN) can be widely used.

  The preferable content of the acrylonitrile-styrene copolymer (D) is 5 to 30 parts by mass, more preferably 7 parts by mass or more, and further preferably 10 parts by mass or more with respect to 100 parts by mass of the polycarbonate resin. Yes, more preferably 25 parts by mass or less, still more preferably 23 parts by mass or less, and particularly preferably 20 parts by mass or less.

[Carbon black (E)]
The thermally conductive polycarbonate resin composition of the present invention preferably contains carbon black (E). As carbon black (E), there is no restriction | limiting in the kind, raw material seed | species, and a manufacturing method, Furnace black, channel black, acetylene black, ketjen black, etc. can be used. The number average particle diameter is not particularly limited, but is preferably about 5 to 60 nm. By containing carbon black having a number average particle diameter in such a range, it becomes easy to obtain a composition in which blisters hardly occur at high temperatures.

Nitrogen adsorption specific surface area of the carbon black (E) ^{(unit: m} 2 / g) is preferably usually less than 1000 m ² / g, is preferably Among them 50 to 400 m ² / g. Setting the nitrogen adsorption specific surface area to less than 1000 m ² / g is preferred because the fluidity of the heat conductive polycarbonate resin composition of the present invention and the appearance of the molded product tend to be improved. The nitrogen adsorption specific surface area can be measured according to JIS K6217.

The DBP (dibutyl phthalate) absorption amount of carbon black (E) ^is preferably less than 300 cm 3/100 g, is preferably Among them 30~200cm ³ / 100g. The DBP absorption amount by less than 300 cm ^3/100 g, preferably tends to increase the appearance of fluidity and a molded article of the thermally conductive polycarbonate resin composition of the present invention.
Incidentally, DBP absorption ^(unit: cm 3 / 100g) can be measured according to JIS K6217. The carbon black used in the present invention is not particularly limited with respect to its pH, but it is usually 2 to 10, preferably 3 to 9, and more preferably 4 to 8.

  Carbon black (E) can be used alone or in combination of two or more. Furthermore, the carbon black (E) can be granulated using a binder, and can also be used in a master batch that is melt-kneaded at a high concentration in another resin. By using the melt-kneaded master batch, the handling property during extrusion and the dispersibility improvement in the resin composition can be achieved. Examples of the resin include polystyrene resin, polycarbonate resin, acrylic resin, and the like.

  The preferable content of carbon black (E) is 0.5 to 5 parts by mass, more preferably 0.8 parts by mass or more, and further preferably 1 part by mass or more with respect to 100 parts by mass of the polycarbonate resin (A). More preferably, it is 4 parts by mass or less, and further preferably 3 parts by mass or less.

[Release agent]
Moreover, it is preferable that the heat conductive polycarbonate resin composition of this invention contains a mold release agent. Preferable examples of the release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15000, polysiloxane silicone oils, and the like.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acid. Here, the aliphatic carboxylic acid includes alicyclic carboxylic acid. Among these, preferable aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, mellicic acid, tetrariacontanoic acid, montanic acid, adipine Examples include acids and azelaic acid.

  As aliphatic carboxylic acid in ester of aliphatic carboxylic acid and alcohol, the same thing as the said aliphatic carboxylic acid can be used, for example. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, monovalent or polyvalent saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or aliphatic saturated polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the term “aliphatic” is used as a term including alicyclic compounds.

  Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. Is mentioned.

  In addition, said ester may contain aliphatic carboxylic acid and / or alcohol as an impurity. Moreover, although said ester may be a pure substance, it may be a mixture of a plurality of compounds. Furthermore, the aliphatic carboxylic acid and alcohol which combine and comprise one ester may each be used 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate Examples thereof include rate, glycerol distearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

  Examples of the aliphatic hydrocarbon having a number average molecular weight of 200 to 15000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. Here, the aliphatic hydrocarbon includes alicyclic hydrocarbons. Further, these hydrocarbons may be partially oxidized.

Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable.
The number average molecular weight of the aliphatic hydrocarbon is preferably 5000 or less.
The aliphatic hydrocarbon may be a single substance, but even a mixture of various constituent components and molecular weights can be used as long as the main component is within the above range.

  Examples of the polysiloxane silicone oil include dimethyl silicone oil, methylphenyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

  In addition, 1 type may contain the release agent mentioned above, and 2 or more types may contain it by arbitrary combinations and a ratio.

  The content of the release agent is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and usually 2 parts by mass or less, preferably 1 with respect to 100 parts by mass of the polycarbonate resin (A). It is below mass parts. When the content of the release agent is less than the lower limit of the range, the effect of releasability may not be sufficient, and when the content of the release agent exceeds the upper limit of the range, hydrolysis resistance And mold contamination during injection molding may occur.

[Flame retardants]
Moreover, it is also preferable that the heat conductive polycarbonate resin composition of this invention contains a flame retardant. Examples of the flame retardant include halogen-based, phosphorus-based, silicone-based, nitrogen-based, metal salt-based flame retardant, and the like, and any known amount can be blended in a necessary amount, for example, condensed phosphate ester, Phosphazene, silicone compounds, sulfonic acid metal salts, polytetrafluoroethylene and the like are preferably used. By using these alone or in combination, a thermally conductive polycarbonate resin composition having desired flame retardancy can be obtained.

  When the flame retardant is a sulfonic acid metal salt, a silicone compound, or polytetrafluoroethylene, the content of the flame retardant is preferably 0.01 parts by mass or more, more preferably 100 parts by mass of the polycarbonate resin (A). Is 0.03 parts by mass or more, and the upper limit thereof is preferably 5 parts by mass or less, more preferably 2 parts by mass or less. When the flame retardant is a condensed phosphate ester or phosphazene, it is preferably 1 part by mass or more, more preferably 5 parts by mass or more with respect to 100 parts by mass of the polycarbonate resin (A), and the upper limit thereof is preferably 30. It is 15 parts by mass or less, more preferably 15 parts by mass or less. When the flame retardant content is less than the lower limit of the above range, it is difficult to obtain an effect of improving flame retardancy, and when it exceeds the upper limit, mechanical strength, heat and humidity resistance, thermal stability, etc. may be reduced. is there. 1 type may be contained for a flame retardant and 2 or more types may be contained by arbitrary combinations and a ratio.

[Other ingredients]
The heat conductive polycarbonate resin composition of the present invention may contain other components other than those described above as necessary, as long as desired physical properties are not significantly impaired. Examples of other components include resins other than polycarbonate resins and various resin additives other than those described above. In addition, 1 type may contain other components and 2 or more types may contain them by arbitrary combinations and ratios.

Other resins Examples of the other resins include thermoplastic polyester resins such as polyethylene terephthalate resin, polytrimethylene terephthalate, and polybutylene terephthalate resin;
Polystyrene resin, high impact polystyrene resin (HIPS), acrylonitrile-styrene-acrylic rubber copolymer (ASA resin), acrylonitrile-ethylenepropylene rubber-styrene copolymer (AES resin), acrylonitrile-butadiene-styrene copolymer ( Styrene resins such as ABS resin); polyolefin resins such as polyethylene resins and polypropylene resins; polyamide resins; polyimide resins; polyether imide resins; polyurethane resins; polyphenylene ether resins;
In addition, 1 type may contain other resin and 2 or more types may contain it by arbitrary combinations and ratios.
When other resins are contained, it is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and more preferably 20 parts by mass or less, in a total of 100 parts by mass of the polycarbonate resin and other resins. More preferably.

Resin additives Examples of resin additives include heat stabilizers, antioxidants, UV absorbers, dyes and pigments, antistatic agents, antifogging agents, lubricants, antiblocking agents, plasticizers, dispersants, antibacterial agents, etc. Is mentioned. In addition, 1 type may contain resin additive and 2 or more types may contain it by arbitrary combinations and a ratio.

[Method for producing thermally conductive polycarbonate resin composition]
There is no restriction | limiting in the manufacturing method of the heat conductive polycarbonate resin composition of this invention, The manufacturing method of a well-known polycarbonate resin composition can be employ | adopted widely, and polycarbonate resin (A), pitch-type carbon fiber (B), and PAN-type carbon fiber (C) and other components to be blended as necessary are mixed in advance using various mixers such as a tumbler and a Henschel mixer, and then Banbury mixer, roll, Brabender, single-screw kneading extruder, two Examples thereof include a melt kneading method using a mixer such as a shaft kneading extruder or a kneader. When using a twin-screw kneading extruder, the pitch-based carbon fiber (B) and the PAN-based carbon fiber (C) are preferably side-fed.
The temperature for melt kneading is not particularly limited, but is usually in the range of 240 to 320 ° C.

The heat conductive polycarbonate resin composition of the present invention has a high flexural modulus, but the value is preferably 18,000 MPa or more, more preferably 18,500 MPa or more, and further preferably 18,900 MPa or more. The tensile modulus is preferably 21,000 MPa or more, more preferably 21,500 MPa or more. Here, the methods for measuring the flexural modulus and tensile modulus are as described in detail in the examples.
Further, the thermally conductive polycarbonate resin composition of the present invention is characterized by a low density, but the value is preferably 1.45 g / cm ³ or less, more preferably 1.40 g / cm ³ or less, More preferably, it is 1.38 g / cm ³ or less.

[Molding]
The pellets obtained by pelletizing the above-described polycarbonate resin composition are molded into various molded products by various molding methods. Further, the resin melt-kneaded by an extruder can be directly molded into a molded product without going through the pellets.
The shape of the molded product is not particularly limited and can be appropriately selected according to the use and purpose of the molded product. For example, a plate shape, a plate shape, a rod shape, a sheet shape, a film shape, a cylindrical shape, an annular shape, Examples include a circular shape, an elliptical shape, a polygonal shape, an irregular shape, a hollow shape, a frame shape, a box shape, and a panel shape.

  The method for molding the molded body is not particularly limited, and a conventionally known molding method can be employed.For example, an injection molding method, an injection compression molding method, an extrusion molding method, a profile extrusion method, a transfer molding method, a hollow molding method, Gas assisted hollow molding method, blow molding method, extrusion blow molding, IMC (in-mold coating molding) molding method, rotational molding method, multilayer molding method, two-color molding method, insert molding method, sandwich molding method, foam molding method And a pressure molding method.

  The thermally conductive polycarbonate resin composition of the present invention is a resin having high thermal conductivity and excellent mechanical properties such as impact resistance, tensile properties and bending properties, and also excellent fluidity, high dimensional accuracy and self-tapping strength. Since it is a material, a molded product obtained by molding the material is suitable for various electronic and electric devices, personal computers, cameras, various precision devices, various portable terminal parts and housings, and the like. In particular, as camera parts, lens barrels, camera housings, and various parts for digital cameras and digital video cameras, for example, elements and parts such as solid-state image sensors, photo sensors, A / D conversion elements, imagers, etc. It is useful as a component (frame body, frame) that holds the element, and by efficiently releasing the heat generated when executing a large amount of optical signal processing at high speed, deformation of the element and component is prevented, and high S / This is preferable because a clear image with an N ratio can be realized.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples, and can be arbitrarily modified and implemented without departing from the gist of the present invention.
Each raw material component used in the following Examples and Comparative Examples is as shown in Table 1 below.

(Examples 1-6, Comparative Examples 1-5)
Using a twin screw extruder (“TEX30HSST” manufactured by Nippon Steel Works), each component described in Table 1 above was used at a cylinder temperature of 290 ° C., a screw rotation speed of 200 rpm, and a discharge rate of 20 kg / hr. It adjusted so that it might become the ratio (all displayed in a mass part) shown in following Table 2, and the pitch-type carbon fiber, the PAN-type carbon fiber, and the glass fiber were side-feeded, and the pellet of the polycarbonate resin composition was obtained.

[Manufacture of ISO multipurpose test pieces]
After drying the pellet obtained above at 100 ° C. for 5 hours, using an injection molding machine (“J55-60H” manufactured by Nippon Steel Works), cylinder set temperature 280-300 ° C., mold temperature 100 ° C., injection time Injection molding was performed under conditions of 2 seconds and a molding cycle of 40 seconds, and an ISO multipurpose test piece (4 mm thick) was injection molded.

[Tensile modulus]
The tensile elastic modulus (unit: MPa) was measured using the ISO multipurpose test piece (4 mm thickness) in accordance with ISO standard 527-1 and ISO527-2.
[Bending elastic modulus]
Based on ISO178, the flexural modulus (unit: MPa) was measured at 23 ° C. using the ISO multipurpose test piece (4 mm thickness).

[Measurement of thermal conductivity (unit: W / m · K)]
The ISO multipurpose test piece (4 mm) obtained above was cut into a slice of 0.15 to 0.5 mm thickness, and this was used as a sample. Temperature phase thermal analyzer “ai-Phase Mobile1” manufactured by I-Phase Co., Ltd. And measured in the MD direction.

[Self-tap breaking torque (unit: N · m)]
After drying the pellet obtained above at 100 ° C. for 5 hours, using an injection molding machine (“J55-60H” manufactured by Nippon Steel Works) at a cylinder set temperature of 290 to 310 ° C. and a mold temperature of 100 ° C., Self-tapping in which a boss hole of outer diameter 7.63 mm x inner diameter 2.61 mm x height 10 mm, outer diameter 7.33 mm x inner diameter 2.44 mm x height 10 mm is formed on a plate-like portion of 70 mm x 45 mm x 3 mm Test boss hole specimens were injection molded.
Screw the screw (M3 × 6 P type, thread diameter 3.02mm, thread valley diameter 2.17mm) to a hook ratio of 34% into the two boss holes of the obtained test piece with a torque screwdriver. Torque to break due to hole cracking was measured and used as self-tap breaking torque.

[Evaluation of fluidity: spiral flow flow length (unit: mm)]
As an evaluation of fluidity, the spiral flow flow length (unit: mm) of the resin composition was evaluated using an injection molding machine (“J55-60H” manufactured by Nippon Steel Works). That is, after the pellets obtained above were dried at 120 ° C. for 4 hours or more, the injection pressure was 150 MPa, the injection speed was 60 mm / sec, the cylinder temperature was 320 ° C., the injection time was 2 sec, the cooling was 7 sec, the mold temperature was 100 The conditions were C. and a suck back of 2 mm.
Moreover, the shape of the evaluated resin molded product is a long resin molded product having a cross section of 2 mm in thickness and a width of 1.5 mm, and has a spiral shape. This spiral long resin molded product is shown in FIG. In FIG. 1, the central member represents the gate 1, and the size of the spiral long resin molded product is the distance between the centers of the long resin molded product (dimension h <b> 1 in the major axis direction) × (short axis Direction dimension h2) = 90 mm × 105 mm.
The spiral flow length indicates that the larger the value, the better the fluidity.
The above evaluation results are shown in Table 2 below.

  The thermally conductive polycarbonate resin composition of the present invention is a polycarbonate resin material having high thermal conductivity, light weight and excellent rigidity, and excellent fluidity and self-tapping strength. It is suitable for parts and housings of computers, cameras, various precision devices, and various portable terminals. In particular, as a camera part, it can be particularly suitably used for a lens barrel, a camera casing, and various parts for a digital camera or a digital video camera, for example, and has very high industrial applicability.

Claims (3)

  It contains 10 to 100 parts by mass of pitch-based carbon fiber (B) and 10 to 100 parts by mass of PAN-based carbon fiber (C) with respect to 100 parts by mass of polycarbonate resin (A), and the contents of (B) and (C) The heat conductive polycarbonate resin composition characterized by having a mass ratio ((B) / (C)) of 1 or more.   Furthermore, the heat conductive polycarbonate resin composition of Claim 1 which contains 5-30 mass parts of acrylonitrile-styrene type copolymers (D) with respect to 100 mass parts of polycarbonate resin (A).   A molded product formed by molding the thermally conductive polycarbonate resin composition according to claim 1.