JP2010077407A - Thermally conductive resin composition, method for producing the same and molded product of thermally conductive resin - Google Patents

Abstract

[PROBLEMS] To suppress the breakage and cutting of carbon fibers in a production process such as kneading and molding, enable continuous mass production, perform industrial production, and have excellent heat conductivity unique to carbon fibers. An electrically conductive resin composition and a method for producing the same are provided, and a thermally conductive resin molded article having excellent thermal conductivity using the same is provided.
A heat conductive resin composition comprising a resin component (A) of a base material, an organic compound (E) incompatible with the resin component, and a carbon fiber (B), the carbon fiber (B) However, the average layer spacing (d ₀₀₂ ) of the (002) plane determined by X-ray diffraction is 0.3367 nm or more and less than 0.3440 nm.
[Selection figure] None

Description

  The present invention includes a carbon fiber that is prevented from being damaged or cut in kneading or molding in a production process, and has a thermal conductivity unique to carbon fiber, a method for producing the same, and a method for producing the same. The present invention relates to a thermally conductive resin molded body.

  Thermoplastic resins have excellent moldability, low cost, corrosion resistance, etc., so there are a variety of electronic parts, machine parts, automotive parts, office supplies, household tableware, and interior / exterior materials for electrical appliances. It is used as an important material in various industrial fields. In particular, in electronic equipment applications, thermal conductivity for efficiently dissipating heat generated from various devices is required, but thermoplastic resins are generally not sufficient in thermal conductivity. Such a resin material with poor thermal conductivity, when applied to parts such as electronic devices and housing materials, prevents heat dissipation and induces failure and destruction of these devices and elements.

  As a method for improving the thermal conductivity of a resin, a method of adding a thermal conductive filler is generally known. For example, inorganic fillers with high thermal conductivity such as alumina, boron nitride, and carbon are widely used. In particular, carbon fibers are lighter than other fillers and have little impact on the environment. For this reason, it has been attracting attention as a material with excellent practicality.

For example, according to the method disclosed in Patent Document 1, graphitized carbon containing polycrystallized resin, which is a polymer material, having high crystallinity and boron with an average interlamellar spacing (d ₀₀₂ ) between graphite layers of less than 0.3360. A thermal conductivity of 2.3 W / m · K is obtained in a heat conductive molded body obtained by kneading 70 parts by weight of fibers and 30 parts by weight of aluminum oxide powder with a twin screw extruder and injection molding. Patent Document 2 discloses a pellet for molding a carbon long fiber reinforced synthetic resin product obtained by impregnating a synthetic resin with a carbon long fiber that is entirely or partially coated with an elastic material. By the action of the elastic material coating, It is described that cutting of reinforcing carbon long fibers during molding in injection molding, injection compression molding, or the like can be suppressed. Further, Patent Document 3 discloses that a fine vapor grown carbon fiber (VGCF) having a diameter of 50 to 200 nm is kneaded with a thermoplastic resin while minimizing the breakage of VGCF as much as possible at a blending ratio of 70% by weight. It has been reported that a thermal conductivity of .5 W / m · K can be obtained.

  Patent Document 4 discloses a method for increasing the thermal conductivity of a resin composition by selectively dispersing carbon fibers. Specifically, in two or more kinds of resin mixtures, carbon fibers having a diameter of 1 μm or less are selectively dispersed in one kind of resin phase, so that a maximum ratio of 0.73 W / m · K can be obtained at a blending ratio of 10 wt%. Thermal conductivity is obtained. In such a mixture of different kinds of resins, a method in which a filler is unevenly distributed in a specific resin phase and has a local characteristic region is also called double percolation. It is described as a resin production method.

  However, the methods disclosed in Patent Documents 1 to 4 have several problems.

  The thermally conductive molded body disclosed in Patent Document 1 tends to fail to obtain high thermal conductivity even when carbon fibers having high crystallinity and high thermal conductivity are added at a high blending ratio. For example, even if carbon fiber is blended as high as 160 parts by weight with respect to 100 parts by weight of the resin, only a thermal conductivity of about 3.2 W / m · K has been obtained, and this value can be found in ceramics and metal materials. Compared to 1 to 2 digits, it is low.

  The resin pellets described in Patent Document 2 certainly contain pellet-length carbon fibers, but use special pellet manufacturing equipment for coating carbon fibers with elastic materials and long-fiber carbon fibers (roving). It is necessary to do and lacks practicality. The thermally conductive resin described in Patent Document 3 disperses carbon fibers over a long period of time without applying a high shear force such as a pressure kneader so as not to damage vapor grown carbon fibers (VGCF). Since it is necessary to use a special kneading machine, there is a problem in productivity. Furthermore, VGCF is known to have an excellent thermal conductivity compared to pitch-based carbon fibers, but when fine carbon fibers obtained by a gas phase method are added to a resin at a high blending ratio, its strong aggregation There is a problem that the melt viscosity is remarkably increased by the force and the molding processability is lowered.

  On the other hand, in the heat conductive resin composition described in Patent Document 4, the mechanical strength tends to decrease due to the formation of regions having different characteristics locally. Specifically, the resin phase in which the carbon fibers are unevenly distributed and the resin component phase of the base material have greatly different mechanical properties, so that interface breakage is likely to occur, which includes a serious drawback as a practical material. . Furthermore, although the thermal conductivity is improved as compared with a general blending method, all of them have a value of less than 1 W / m · K, reaching a practical required level as a thermal conductive material. Not in.

  As described above, it is difficult to efficiently produce a resin composition in which carbon fibers are efficiently and uniformly dispersed while maintaining the carbon fiber length. Fiber length that can form a network in the resin composition by suppressing breakage and shortening of the fiber in order to give the resin material the functions such as excellent thermal conductivity and conductivity that the carbon fiber has. There is a need for a thermally conductive resin composition containing carbon fibers having the same, a method for producing the same, and a thermally conductive resin molded body using the composition.

JP 2002-97371 A JP-A-6-270142 JP 2005-325345 A JP 2005-54094 A No. 2603511

Tokyo Tech, Vol. 3, 2000, pp. 7

  The object of the present invention is to suppress the breakage and cutting of carbon fibers in the production process such as kneading and molding, enable continuous mass production and industrial production, and have excellent thermal conductivity specific to carbon fibers. An object of the present invention is to provide a thermally conductive resin composition and a method for producing the same, and to provide a thermally conductive resin molded article having excellent thermal conductivity using the composition.

  In the production of a thermally conductive resin composition containing carbon fibers, the present inventors have paid attention to the fact that breakage or cutting of the carbon fibers generated in the production process strongly affects the thermal conductivity of the composition. The method that can prevent the breakage and cutting of the steel was investigated. As a result, a carbon fiber having a specific crystallite size and having a specific structure having a specific crystal plane spacing is used at the same time as the specific organic compound, thereby producing the thermal conductive resin composition, That is, the present inventors have found that carbon fiber can be prevented from being broken or cut in a kneading or molding process of a composition containing a resin and carbon fiber, and the thermal conductivity of the composition can be significantly improved.

  The carbon fiber having a specific structure found by the present inventors has a high thermal conductivity based on the lattice vibration of the crystal lattice because most of the structure is composed of a crystalline graphite structure with few defects. . The carbon fiber having such a high thermal conductivity can impart excellent thermal conductivity to the resin with a small addition amount. In addition, the carbon fiber having a specific structure according to the present invention has moderate flexibility because it has a region with low crystallinity in a part of the structure. Such a carbon fiber having moderate flexibility can effectively prevent breakage and cutting in the kneading and molding process with the resin.

  In addition, the specific organic compound of the present invention has a moderate incompatibility with the base resin and a good affinity for the carbon fiber. While such an organic compound is finely dispersed in the base material resin, it functions to disperse the carbon fibers and at the same time partially bond the carbon fibers by interaction with the carbon fibers. That is, since a network structure in which carbon fibers are partially bonded in a resin, that is, a heat conductive network structure, is formed, the thermal conductivity of the composition can be remarkably improved. Furthermore, since the melt viscosity of the base resin is reduced by the addition of the organic compound, the shearing force applied to the carbon fiber in the kneading or molding process is reduced, and the breakage or cutting of the carbon fiber can be further suppressed.

  That is, the mechanism of high thermal conductivity of the present invention is that the carbon fiber has high thermal conductivity and moderate flexibility at the same time, so that breakage and cutting in the kneading and molding process with the resin can be suppressed. It is possible to impart excellent high thermal conductivity to the resin, and at the same time, the presence of an appropriate binder forms a network structure of carbon fibers in the thermal conductive resin composition, that is, a thermal conductive network structure. It is considered that high thermal conductivity can be achieved with a small amount of carbon fiber added.

That is, this invention is a heat conductive resin composition containing the resin component (A) of a base material, an organic compound (E) incompatible with this, and carbon fiber (B), B) relates to a thermally conductive resin composition having an average layer spacing (d ₀₀₂ ) of (002) planes determined by X-ray diffraction of 0.3367 nm or more and less than 0.3440 nm.

  Moreover, this invention is a manufacturing method of the said heat conductive resin composition, Comprising: Carbon fiber (B) is supplied and mixed with the molten resin component (A) and organic compound (E), It is characterized by the above-mentioned. The present invention relates to a method for producing a thermally conductive resin composition.

  Moreover, this invention relates to the heat conductive resin molded object shape | molded using the said heat conductive resin composition.

  The thermally conductive resin composition of the present invention suppresses breakage and cutting of carbon fibers in the production process such as kneading and molding, and uses this to provide excellent thermal conductivity, electromagnetic wave shielding properties, and conductivity unique to carbon fibers. A molded body having the same can be obtained. Moreover, the manufacturing method of the heat conductive resin composition of this invention can perform continuous industrial manufacture, and can manufacture a heat conductive resin composition efficiently.

It is a figure which shows the thermography which shows the heat conductivity of an example of the heat conductive resin molding of this invention in comparison with stainless steel. 2 is a diagram showing an image obtained by Example 1 with an optical microscope. FIG. It is a figure which shows the image obtained by the optical microscope about Example 4. FIG. It is a figure which shows the image obtained by the optical microscope about the comparative example 1. FIG.

The heat conductive resin composition of the present invention is a heat conductive resin composition containing a resin component (A) as a base material, an organic compound (E) incompatible with the resin component, and carbon fibers (B). The carbon fiber (B) is characterized in that the carbon fiber (B) has an (002) plane average layer spacing (d ₀₀₂ ) of 0.3367 nm or more and less than 0.3440 nm determined by X-ray diffraction. .

  The resin component (A) of the base material used in the heat conductive resin composition of the present invention is a base material of the heat conductive resin composition, and any thermoplastic resin used in the molding field can be used. Can also be applied. As such a resin component (A), for example, a polystyrene-based resin such as ABS or a polyester-based resin can be mentioned as a preferable one, and these can be used alone or in combination of two or more. Polystyrene resins are widely used in electrical products and are not only excellent in practical properties such as heat resistance, wear resistance, chemical resistance, and workability, but also blended and molded with various fillers and other resins. There are advantages such as easy processing.

The polyester resin may be a synthetic polyester, but a biodegradable polyester resin is preferable from the viewpoint that environmental destruction can be suppressed. Examples of biodegradable polyester resins include biomass-derived resins and derivatives thereof. Biomass-derived resin refers to a resin containing as a main component a resin made from biomass, and its derivatives are partly substituted or modified by other compounds or functional groups. Say something. Biomass-derived resins are superior in biocompatibility compared to petroleum-based resins, and are particularly preferable for equipment or component materials that are in direct contact with the human body or living organisms. In addition, the environmental load inherent in the material itself, such as resource saving measures and CO ₂ emission reduction, can be greatly reduced. Specific examples of such biomass-derived resins include polylactic acid (PLA), polycaprolactone (PCL), polyhydroxybutyric acid (PHB), polyhydroxyalkanoate (PHA), polybutylene succinate (PBS), Examples thereof include cellulose acetate, starch resin, and derivatives thereof include aromatic carboxylic acid, alicyclic carboxylic acid, saturated aliphatic carboxylic acid, unsaturated aliphatic carboxylic acid, aliphatic diol, alicyclic diol, Mention may be made of copolymers with aromatic diols and the like.

  Among these, polylactic acid (PLA) and its derivatives can be mentioned as preferable ones. Examples of the polylactic acid derivative include polyethylene glycol-modified PLA and acrylate-modified PLA. Examples of the polylactic acid alloy include alloys with PCL, PBS, polycarbonate, polymethyl methacrylate, and the like. These polyester-based resins can be used alone or in combination of two or more, and can be used in any combination with other thermoplastic resins.

The carbon fiber (B) used in the thermally conductive resin composition of the present invention has an average layer spacing (d ₀₀₂ ) of the (002) plane determined by X-ray diffraction of 0.3367 nm or more and less than 0.3440 nm, and more Preferably, it is 0.3390 nm or more and less than 0.3440 nm.

The average layer spacing (d ₀₀₂ ) of (002) planes determined by X-ray diffraction is the distance between the carbon layer planes in the benzenoid structure in which the network-like carbon layers having a six-membered carbon condensed structure are laminated, In the case of graphite whose carbon layer surface is a plane, it is 0.3354 nm.

If the average layer spacing (d ₀₀₂ ) of the carbon fiber (B) is 0.3367 nm or more, the carbon fiber can be prevented from being stiffened due to excessive crystallization. And cutting can be suppressed. Also, if the average layer spacing (d ₀₀₂ ) is less than 0.3440 nm, the interlayer distance is sufficiently small to form a highly crystalline graphite structure, and heat conduction is good, so that the resin composition is high. Thermal conductivity can be imparted. Further, the carbon fiber having an average layer surface separation (d ₀₀₂ ) of 0.3367 nm or more and less than 0.3440 nm can be processed at a relatively low processing temperature for crystallization (graphitization) of 2500 ° C. or less, so that production energy And cost can be kept low.

Moreover, the value calculated _| required as follows can be employ _| adopted for the average space _| interval ( _d002 ) of carbon fiber (B). An X-ray diffraction pattern is obtained by making carbon fiber into powder, filling an aluminum sample cell, and using CuKα rays monochromatized by a graphite monochromator as a radiation source. The peak position of the (002) diffraction line is obtained by the centroid method (a method of obtaining the centroid position of the diffraction line and obtaining the peak position using the corresponding 2θ value). 111) Correct using diffraction lines (28.466 °), and calculate d ₀₀₂ from Bragg's formula d ₀₀₂ = λ / 2 · sin θ. Here, the wavelength λ of the CuKα ray is 0.15418 nm.

  The carbon fiber (B) has a crystallite size Lc in the C-axis direction of 10 nm to 35 nm, preferably 10 nm to 20 nm.

  A crystallite is a unit that can be regarded as a single crystal constituting one solid particle, that is, one particle constituting a solid is formed by integrating a plurality of crystallites, and the size of the crystallite is large. As the number of crystal lattices increases, the crystallinity increases. The C-axis direction refers to a direction perpendicular to the carbon layer surface in the benzenoid structure.

  If the crystallite size Lc in the C-axis direction of the carbon fiber is 10 nm or more, the carbon fiber has a size sufficient to obtain high thermal conductivity due to lattice vibration of the crystal lattice, and imparts high thermal conductivity to the resin composition. it can. Further, if the crystallite size Lc is 35 nm or less, it is possible to prevent the carbon fiber from being stiffened due to excessive crystallization, and thus it is possible to suppress breakage or cutting of the carbon fiber in the kneading with the resin or in the molding process. Furthermore, since the carbon fiber having a crystallite size Lc of 10 nm or more and 35 nm or less can be treated at a relatively low temperature of 2500 ° C. or less for crystallization (graphitization), manufacturing energy and cost can be kept low. it can.

Here, as the crystallite size Lc (nm) in the C-axis direction of the carbon fiber (B), a value obtained by a wide angle X-ray diffraction method can be adopted. Specifically, a carbon fiber is cut into a length of 4 cm, and is solidified into a prismatic shape using a mold and an alcohol solution of collodion to obtain a sample. CuKα (Ni filter) is used as the X-ray source, and the output is 40 kV and 20 mA. Then, the crystal size is calculated from the half width of the peak of the plane index (002) obtained by the transmission method using the Scherrer equation, Lc (hkl) = K · λ / β0 · cos θB. Here, Lc (hkl) is the average crystal size in the direction perpendicular to the (hkl) plane, K is 1.0, λ is the wavelength of the X-ray, and β0 is (βE ² −β1 ² ) ^{1 / 2} , θB is the Bragg angle, βE is the apparent half width (measured value), and β1 is 1.05 × 10 ⁻² rad.

As described above, in the carbon fiber (B) used in the heat conductive resin composition of the present invention, the average layer spacing (d ₀₀₂ ) of the (002) plane determined by X-ray diffraction is 0.3367 nm or more and less than 0.3440 nm. It is preferable that the crystallite size Lc in the C-axis direction is 10 nm or more and 35 nm or less. However, even if the average layer spacing (d ₀₀₂ ) of the (002) plane determined by X-ray diffraction is outside the above range, the C axis If the crystallite size Lc in the direction is 10 nm or more and 35 nm or less, the resin composition can be provided with preferable thermal conductivity, and the breakage and cutting of the carbon fiber in the kneading and molding process with the resin can be suppressed. In addition, a thermally conductive resin composition can be provided that provides a molded article having excellent thermal conductivity, electromagnetic wave shielding properties, and electrical conductivity.

  The average fiber length of the carbon fiber (B) is preferably a plane orientation, that is, a length capable of forming a two-dimensional network structure, and is preferably 0.1 mm or more and 50 mm or less. The carbon fiber (B) having such an average fiber length forms a network structure very easily even in a low blending ratio in the presence of the organic compound (E), and the carbon fibers (B) are very close to each other. A state or a direct contact state is formed, and a heat energy propagation loss is remarkably reduced, and heat conduction is performed efficiently. On the other hand, if the average fiber length of the carbon fibers (B) is 50 mm or less, the entanglement between the carbon fibers (B) prevents the resin from being mixed and molded, and the nozzle is clogged during injection molding. Can be suppressed. Moreover, since it is easy to orient in the flow direction or the surface direction of the resin at the time of molding, both the thermal conductivity and the anisotropic thermal conductivity can be remarkably improved in the obtained molded body as compared with the conventional one. This is because the carbon fibers (B) in the molded body are oriented while maintaining contact or extremely close to each other, and a network structure is formed, so that the contact area between the carbon fibers (B) or the heat conduction thereof. This is because the effective area of the carbon fiber (B) involved in the increase increases and the thermal resistance significantly decreases.

  As the average fiber length of the carbon fiber (B), a value obtained by a measuring method such as a microscope method, a laser diffraction / scattering method, or a dynamic light scattering method can be adopted.

  As the carbon fiber (B), one having an average diameter of 1 μm or more and 50 μm or less is preferably used. When the average diameter of the carbon fiber (B) is 1 μm or more, the carbon fiber (B) is less likely to aggregate and can be easily dispersed in mixing with the resin. On the other hand, if the average diameter is 50 μm or less, it can be uniformly dispersed in the resin, and appearance defects due to exposure of aggregates of carbon fibers (B) to the surface of the molded product can be suppressed. . The average diameter of such a carbon fiber (B) can be determined by microscopy.

  The carbon fiber (B) preferably has an aspect ratio of 2 or more and 50000 or less, more preferably 10 or more and 50000 or less. The aspect ratio is a ratio of the fiber length to the average diameter of the carbon fiber (B).

  The carbon fiber (B) preferably has a thermal conductivity of 70 W / m · K or more and 600 W / m · K or more. If the thermal conductivity of the carbon fiber (B) is in the above range, it has a flexibility capable of suppressing breakage during kneading with the resin component, and has sufficient thermal conductivity, so that it has high thermal conductivity. A resin composition having is obtained. Since the carbon fiber (B) has a thermal conductivity in the above range, it has particularly excellent thermal conductivity in the fiber axis direction, and is oriented in the flow direction of the resin by injection molding or the like, and is anisotropic in the resulting molded body. It is possible to control the direction and amount of movement of heat.

  As the thermal conductivity, a measured value by a measuring method such as a laser flash method, a flat plate heat flow meter method, a temperature wave thermal analysis method (TWA method), a temperature gradient method (flat plate comparison method) can be adopted.

  The carbon fiber (B) is synthesized by pitch system, PAN system, arc discharge method, laser evaporation method, CVD method (chemical vapor deposition method), CCVD method (catalytic chemical vapor deposition method), etc. Can be used. Among these, carbon fibers obtained by pitch-based and further graphitized are excellent in crystallinity and excellent in thermal conductivity in the fiber axis direction. In particular, carbon (nano) tubes, carbon (nano) horns, carbon fibers, etc. produced in the mesophase (anisotropic) pitch system and in the gas phase have an anisotropic graphite structure with respect to the fiber axis direction. Compared with the carbon fiber which has the above thermal conductivity and has an isotropic graphite structure, higher thermal conductivity can be imparted to the base thermoplastic resin (A).

  Next, the manufacturing method of the said carbon fiber (B) is described. As a raw material for carbon fiber, any hydrocarbon compound that can be easily graphitized can be used. Examples thereof include condensed polycyclic hydrocarbon compounds such as naphthalene and phenanthrene, and condensed heterocyclic compounds such as petroleum and coal-based pitch. In particular, by using petroleum pitch, coal pitch, preferably optically anisotropic pitch, that is, mesophase pitch, a highly heat conductive polymer composition and heat conductive molded body can be obtained. The mesophase pitch is not particularly limited as long as spinning is possible, but a mesophase content of 100% is preferable from the viewpoints of high thermal conductivity, spinnability, and quality stability. The above raw materials are spun by a spinning method (melt spinning method, melt blow method, centrifugal spinning method, vortex spinning method, etc.) to obtain pitch-based carbon fibers. Next, for example, a method of heat treatment at a relatively low temperature of 200 to 400 ° C. in an oxidizing gas atmosphere such as nitrogen dioxide or oxygen, a method of treating in an oxidizing aqueous solution such as nitric acid or chromic acid, light, and γ An infusible fiber is obtained using a method of polymerizing with a wire or the like. Further, the infusible fiber is graphitized by adding a graphitization catalyst. As the graphitization catalyst, at least one selected from boron compounds such as boron carbide, boron oxide, boron nitride, and boron alone is used. The addition amount of the graphitization catalyst is preferably 0.1 to 10% by mass as the boron content with respect to the carbon fiber. If the boron content is in the above range, it is preferable because the catalyst effect is sufficiently exerted and the boron compound remains little. The graphitization temperature is preferably 1500 ° C. or higher and 2500 ° C. or lower. When the graphitization temperature is 1500 ° C. or higher, carbon fibers having the crystallite size Lc and the average layer spacing can be produced in a practical processing time. Moreover, if it is 2500 degrees C or less, the surplus energy thrown into heating can be suppressed and manufacturing cost can be suppressed low.

  The raw material carbon fiber may be used as it is, but may be used after being treated with a sizing agent, if necessary.

  The carbon fiber (B) can be used after partly or entirely treating the carbon fiber (B) as necessary. Specifically, the surface treatment includes oxidation treatment, nitridation treatment, nitration, sulfonation, or the surface of the functional group or carbon fiber (B) introduced into the surface by these treatments, metal, metal compound, organic A treatment for attaching or bonding a compound or the like can be given. Specific examples of the functional group include oxygen-containing groups such as hydroxyl groups, carboxyl groups, carbonyl groups, nitro groups, amino groups, and nitrogen-containing groups. In the carbon fiber (B) in which such a functional group or compound is introduced into a part of the surface, the chemical interaction with the base material thermoplastic resin (A) such as a polyester resin is strengthened, and thus obtained. Mechanical strength is improved in the molded body.

  Examples of the surface treatment of the carbon fiber (B) include a treatment for bonding or attaching a functional group or compound having an interaction with the organic compound (E) to the surface. The carbon fiber (B) subjected to such a surface treatment has a stronger bond with the organic compound (E), and can further improve the thermal conductivity in the molded body. Specific examples include surface treatment with various carboxylic acids and the like.

  Further, examples of the surface treatment include a hydrophobic treatment on the surface of the carbon fiber (B). Examples of the hydrophobic treatment include a method of performing a heat treatment in an inert gas atmosphere, a fluorination treatment, and the like. Such a hydrophobized carbon fiber (B) exhibits a stronger interaction with a resin having a low polarity.

  The carbon fiber (B) is preferably contained in the range of 1% by mass to 40% by mass with respect to the total mass of the thermally conductive resin composition, and more preferably 5% by mass to 20% by mass. is there. If the content is 1% by mass or more, sufficient thermal conductivity can be obtained. On the other hand, if it is 40 mass% or less, especially in the heat conductive resin composition containing the low density carbon fiber (B), the increase in the volume fraction is suppressed, and the composition melts due to the entanglement of the carbon fibers. An increase in viscosity can be suppressed, and excellent moldability can be obtained.

  Moreover, you may make the heat conductive resin composition of this invention contain the carbon fiber (C) and carbon compound (D) which have a fiber length shorter than the average fiber length of the said carbon fiber (B). As carbon fiber (C) with short fiber length, aggregates, such as carbon fiber with high crystallinity, can be illustrated as a preferable thing. Examples of the average fiber length of the carbon fiber (C) include 5 nm or more and less than 100 μm.

  Moreover, as a carbon compound (D), graphite, expanded graphite, exfoliated graphite, etc. can be mentioned as a preferable thing. The average particle size of the carbon compound (D) is preferably 1 μm or more and 300 μm or less because mixing with the resin component (A) is easy.

  By using together such carbon fiber (C) and carbon compound (D), the antistatic property and electromagnetic wave shielding property can be further improved in the obtained molded article. This improves the conductivity of the resin by including short-fiber-length carbon fibers (C) and carbon compounds (D) that exist in a random state with respect to the oriented long-fiber carbon fibers (B). Thus, it is possible to highly control the thermal conductivity and the like of the obtained molded body.

  The content of such short fiber length carbon fiber (C) or carbon compound (D) is 0.5% by mass or more and 20% by mass or less with respect to the total mass of the heat conductive resin composition. it can.

  The organic compound (E) used in the thermally conductive resin composition of the present invention is incompatible with the resin component (A) of the base material, and is particulate in the thermoplastic resin (A) of the base material. It forms a dispersed phase. Here, incompatible means a material in which a dispersed phase is formed with a size of 0.1 μm or more with respect to the resin component (A) of the base material and exhibits optical incompatibility in the visible light region. In addition, in the mixing of different types of resins or resins and organic compounds, complete thermodynamic compatibility (being one phase at the molecular level) is extremely rare, and partial compatibility makes it appear uniform. Even in this case, it is generally present in a dispersed state in a microscopic field of submicron or less. Therefore, “incompatible” or “not completely compatible” includes a different resin or a mixed system of a resin and an organic compound. The incompatibility in the organic compound (E) used in the present invention indicates an incompatible state in a macroscopic view as described above, including a partially compatible state.

  In the resin component (A), the organic compound (E) is preferably dispersed in the range of 0.1 μm or more and 500 μm or less as an average particle size. If the average particle size of the organic compound (E) is 0.1 μm or more, optical incompatibility in the visible light region is recognized, and based on the incompatibility, a network structure with the carbon fiber (B) described later The thermal conductivity can be improved. On the other hand, when the average particle diameter is 500 μm or less, aggregation in the resin component (A) can be suppressed, and interface fracture due to macrophase separation can be suppressed.

  Here, the average particle diameter can be a value measured by a microscopic method.

  In addition, the organic compound (E) having such an average particle diameter is a bonded body in which two or more carbon fibers (B) are coordinated on the surface or inside thereof due to the interaction with the carbon fibers (B). Form. As a form of this bonded body, the carbon fiber (B) may be either in the organic compound (E) particles or in a state of penetrating the particles, or in a state of being in contact with the surface. By dispersing this joined body in the base material resin, the particles of the organic compound (E) become a binder for concentrating a plurality of carbon fibers (B), and a network structure is formed in the base material resin component (A). Can be formed. When the average particle diameter of the organic compound (E) is ½ or less of the average fiber length of the carbon fiber (B), aggregation of the carbon fiber (B) on the particulate organic compound (E) is suppressed, and carbon Two-dimensional coordination of the fiber (B) to the particulate organic compound (E) can be promoted. For this reason, the network structure by the carbon fiber (B) and the organic compound (E) dispersed in the matrix resin component (A) is easily formed, and even if the blending amount of the carbon fiber (B) is small, it is sufficient. High thermal conductivity can be obtained. Bonding forms that form the coordination of the carbon fiber (B) to the organic compound (E) include physical adsorption, electrostatic adsorption, hydrophobic interaction, magnetic adsorption, in addition to chemical bonds such as hydrogen bonds and coordinate bonds. Any of joining by geometric factors may be used.

  The organic compound (E) preferably has a melt viscosity lower than that of the resin component (A) and a melting point lower than that of the resin component (A). By using such an organic compound (E), in the melt mixing with the resin component (A), the melt viscosity of the mixture is reduced, the fluidity is improved, and the solid carbon fiber (B) is used as a base resin. It can be easily and uniformly dispersed in the component (A). Specifically, the melting point of the organic compound (E) is preferably 80 to 200 ° C. When the melting point of the organic compound (E) is 80 ° C. or higher, softening and elution due to heat can be suppressed even when the organic compound (E) is used for a part or casing of a product that generates heat such as an electronic device. On the other hand, if the melting point is 200 ° C. or less, even when a biodegradable polyester resin such as polylactic acid which is easily thermally decomposed due to a high molding process is used as the resin component (A), decomposition, gas generation, Discoloration and the like can be suppressed.

  The organic compound (E) has a polarity or solubility parameter (hereinafter referred to as SP value) equal to or less than that of the resin component (A) of the base material, and the difference is the SP value of the thermoplastic resin (A). Is preferably within a range of 30% or less. Organic compounds having the same SP value are generally compatible with each other, but may be incompatible with each other due to the influence of molecular weight, steric structure, and the like. Here, when the organic compound (E) is equivalent to the SP value of the resin component (A), the organic compound (E) has a factor that inhibits the compatibility thereof such as the molecular weight and the three-dimensional structure, and is not compatible with the resin component (A). It is necessary to have compatibility. If the difference in SP value is 30% or less with respect to the value of the resin component (A) of the base material, it is a case where a functional group having reaction activity is included in a part of the molecular structure of the organic compound (E). In addition, macrophase separation in the resin component (A) can be suppressed, and a decrease in thermal conductivity can be suppressed.

  In addition, since the organic compound (E) has a lower polarity or SP value than the resin component (A) of the base material, the carbon fiber (B) having a chemically inert hydrophobic structure surface becomes a resin component ( A) Aggregation can be suppressed by a strong hydrophobic interaction with the organic compound (E) having a lower polarity or SP value. Furthermore, since the organic compound (E) having an SP value in the above range is finely dispersed with the carbon fiber (B) in the resin component (A), the dispersibility of the carbon fiber (B) can be further improved. it can.

  Here, as the SP value, from a qualitative viewpoint, a value theoretically calculated using a general group contribution method (the group contribution method) can be applied. Specifically, it can be calculated using Equation (1). About each physical property value required for calculation, it is described in literature values (for example, DW Van Krevelen and PJ Hoftyzer, PROPERTY OF POLYMERS: THEIR ESTIMATION AND CORRELATION WITH CHEMICAL STRUCTURE, E19. Alternatively, any experimental value may be used.

δ = (ΣEcohi / ΣVmi) ^1/2 (1)
δ: solubility parameter (SP value)
Ecohi: molar cohesive energy of each atomic group EVmi: molar volume of each atomic group As the organic compound (E), ester compounds, olefin compounds, carbonate compounds, amide compounds, silicone compounds, hydrogenated fats and oils, synthetic waxes, and the like It is preferable that it is a low molecular compound whose melting | fusing point chosen from these mixtures is 80 to 200 degreeC, and whose molecular weight is 2000 or less. These types of organic compounds are less likely to cause problems of molecular weight reduction due to hydrolysis, transesterification reaction, etc. with respect to a base resin such as a polyester resin, and because the melt viscosity is low, they are easily finely dispersed in the base resin. There is an advantage of doing.

  Among these, aliphatic carboxylic acid amides, aromatic carboxylic acid amides, and aliphatic carboxylic acid esters having a main chain of molecular structure having 8 to 44 carbon atoms and a molecular weight of 200 to 1500, more preferably 300 to 1000. And a crystalline organic compound selected from aromatic carboxylic acid esters and the like. These can be used alone or in combination of two or more. Many of these crystalline organic compounds having a specific carbon number and molecular weight can be synthesized from natural fats and oils such as vegetable fats and animal fats and are easy to handle and can be obtained at low cost. There are many cases. In addition, when the resin component (A) of the base material is a crystalline resin, an effect of acting as a crystal nucleating agent and greatly shortening the molding cycle can be obtained. The aliphatic carboxylic acid amide, aromatic carboxylic acid amide, aliphatic carboxylic acid ester, and aromatic carboxylic acid ester preferably have one or more polar groups introduced into the molecule. Examples of such polar groups include oxygen-containing groups such as hydroxyl groups, carboxyl groups, and glycidyl groups, nitrogen-containing groups such as amino groups, nitro groups, cyano groups, and isocyanate groups, and fluorine-containing groups. In the above-mentioned compounds in which these polar groups are partially introduced, while having an interaction with the carbon fiber (B), it has a physicochemical action such as hydrogen bonding on the resin component (A) of the base material. In addition, a binder effect that reinforces the interaction between both the resin component (A) and the carbon fiber (B) of the base material is exhibited, and the mechanical strength is improved.

  Specific examples of the organic compound (E) include ricinoleic acid amide, linoleic acid amide, linolenic acid amide, arachidic acid amide, lauric acid amide, palmitic acid amide, oleic acid amide, stearic acid amide, erucic acid amide, N-oleyl palmitic acid amide, N-oleyl oleic acid amide, N-oleyl stearic acid amide, N-stearyl oleic acid amide, N-stearyl stearic acid amide, N-stearyl erucic acid amide, methylene bis stearic acid amide, ethylene bis Lauric acid amide, ethylene biscapric acid amide, ethylene bisoleic acid amide, ethylene bisstearic acid amide, ethylene biserucic acid amide, ethylene bisisostearic acid amide, butylene bisstearic acid amide, p-xylylene bis Carboxylic acid amides such as thetearic acid amide and compounds in which polar groups are introduced in some of these molecules, lauric acid esters, palmitic acid esters, oleic acid esters, stearic acid esters, erucic acid esters, N-oleyl Palmitic acid ester, N-oleyl oleic acid ester, N-oleyl stearic acid ester, N-stearyl oleic acid ester, N-stearyl stearic acid ester, N-stearyl erucic acid ester, methylene bis stearic acid ester, ethylene bis lauric acid ester , Ethylene biscapric acid ester, ethylene bis oleic acid ester, ethylene bis stearic acid ester, ethylene bis erucic acid ester, ethylene bis isostearic acid ester, butylene bis stearic acid ester, - and the like compounds polar group is introduced in a part of the carboxylic acid ester and of these molecules such as xylylene bis stearic acid ester.

  Of the organic compounds (E) listed above, a carboxylic acid amide compound derived from castor oil is particularly preferable. Specific examples include ricinoleic acid amide, stearic acid amide, oleic acid amide, palmitic acid amide, linoleic acid amide, linolenic acid amide, arachidic acid amide, and derivatives thereof. In addition to excellent thermal conductivity, these are derived from biomass, so they have excellent environmental compatibility, safety, productivity, cost, biocompatibility, and dispersion control over polyester resins. It acts as a crystal nucleating agent and can form a network structure with the carbon fiber (B).

  The content of the organic compound (E) in the thermally conductive resin composition is preferably 0.5% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 15% by mass or less. If content of an organic compound (E) is 0.5 mass% or more, the melt viscosity of a composition can be made low enough and carbon fiber (B) can fully be disperse | distributed. On the other hand, if the content of the organic compound (E) is 20% by mass or less, the re-aggregation of the finely dispersed organic compound (E) can be suppressed, and the decrease in mechanical strength due to macrophase separation can be suppressed. It can suppress that the organic compound (E) which aggregated in the molded object obtained is exposed to the surface, and can suppress generation | occurrence | production of the appearance defect and the coating defect.

  Various additives can be blended in the heat conductive resin composition of the present invention as required. Examples of additives include reinforcing agents, flame retardants, foaming agents, deterioration inhibitors, crystal nucleating agents, colorants, antioxidants, heat resistance improvers, light resistance agents, processing stabilizers, antibacterial agents, fungicides, A plasticizer etc. can be mentioned. Specifically, fillers such as mica and talc, organic fibers such as aramid and polyarylate, glass fibers, and plant fibers such as kenaf can be used as the reinforcing agent. Specific examples of the flame retardant include metal hydroxides such as aluminum hydroxide and magnesium hydroxide, nitrogen flame retardants such as melamine and isocyanuric acid compounds, and phosphorus flame retardants such as phosphoric acid compounds. be able to. In addition, various inorganic or organic crystal nucleating agents, coloring agents such as titanium oxide, stabilizers such as radical trapping agents, antioxidants, hydrolysis inhibitors, and antibacterial agents such as silver ions are appropriately blended. Can do.

  As a method for producing the heat conductive resin composition of the present invention, a method of mixing the above various components can be employed. As such a mixing method, a known mixer such as a tumbler mixer, a ribbon blender, a single-screw or multi-screw mixing extruder, a roll or the like can be used. In particular, if carbon fiber (B) is supplied from the side feed or the like to the molten resin component (A) and the incompatible organic compound (E), and mixed, the carbon fiber (B) It is preferable because a resin composition reflecting the high thermal conductivity in the original fiber axis direction of the carbon fiber (B) can be obtained. In addition, when adding a plurality of additives to the resin component (A), additives other than the carbon fiber (B) are added in advance and mixed, and then the carbon fiber (B) is added using a side feed. It is also effective to shorten the mixing time of the carbon fiber (B) and reduce these breaks and crushing. Moreover, in order to ensure sufficient fluidity at the time of melt mixing, it is preferable to appropriately set the apparatus conditions such as clearance adjustment in the cylinder of the mixer, the number of rotations of the screw and the stirring blade, and the melting temperature condition.

  The heat conductive resin molding of this invention was shape | molded using the said heat conductive resin composition, It is characterized by the above-mentioned. As a method for molding the thermally conductive resin molding, a method used for molding a thermoplastic resin such as injection molding, injection compression molding, compression molding, or the like can be applied. It is preferable that the temperature at the time of melt mixing and molding is not less than the melting point of the resin component (A) as a base material and the range in which each component does not deteriorate.

  In the thermally conductive resin molded body of the present invention, a film made of a resin having different thermal conductivity can be formed on the upper or lower portion of the thermally conductive resin molded body. Specific examples of the coating include those formed by laminating or forming thin films using resins having different filler concentrations, addition amounts, orientation directions, and the like, resins having different blending components, and resins having different types as raw materials. The thermally conductive resin molded body on which such a laminated structure or a film made of a thin film is formed can also control the directionality of the thermal conductivity three-dimensionally. In particular, the resin film with low thermal conductivity provided on the upper or lower part of the thermally conductive resin molded body can avoid the state where heat is transmitted directly from the heat source to the molded body surface, and prevents low-temperature burns in the housing of electronic devices. It is particularly effective for countermeasures.

  In addition, a laminated structure or a coating made of a material or paint excellent in heat radiation action can be provided on the surface of the thermally conductive resin molded body of the present invention. By having such a film, the heat dissipation characteristics can be improved.

  Moreover, the laminated structure or film which consists of material from which heat capacity differs can be provided in the surface of the heat conductive resin molding of this invention. By having such a coating, the temperature change on the surface can be dulled, which is effective in a device that directly touches a human body or a living organism or a precision device that dislikes a change in heat.

  Below, although the heat conductive resin composition of this invention and a molded object using the same are demonstrated in detail, the technical scope of this invention is not limited to these.

[Example 1]
[Preparation of Thermally Conductive Resin Composition and Injection Molded Body]
As the resin component (A), commercially available polylactic acid (manufactured by Unitika: melting point 170 ° C., hereinafter referred to as PLA) 85% by mass and the organic compound (E) N'-ethylenebisoleylamide (ITO WAX J-500, ITOHWAX J-500) 5 mass% was dry blended. The obtained mixture was supplied from a hopper port of a continuous kneading extruder (Berstorf, ZE40A × 40D, L / D = 40, screw diameter φ40) whose cylinder temperature was set to 190 ° C., and carbon fiber (B ) 10% by mass of pitch-based carbon fiber (B-2 shown in Table 1) having an anisotropy of 6 mm in fiber length from the side feed port, the total amount of resin and carbon fiber per hour is 15 to 20 kg. / H was supplied. Then, the screw was rotated at 150 rpm, mixed and stirred under melt shearing, then extruded into a strand from the die port of the extruder, cooled in water, then cut into pellets, and the heat conductive resin composition Pellets were obtained.

  The obtained pellets were dried at 100 ° C for 5 hours, and then molded using a 20t injection molding machine (EC20P-0.4A manufactured by Toshiba Machine) under conditions of a cylinder temperature of 190 ° C and a mold set temperature of 25 ° C. , Test pieces (125 mm × 13 mm × 1.6 mm and 125 mm × 13 mm × 3.2 mm) were obtained. The obtained 1.6 mm-thick test piece was subjected to thermal conductivity evaluation and carbon fiber microscopic observation, and the 3.2 mm-thick test piece was subjected to bending strength, flexural modulus, and IZOD impact test. It was.

[Thermal conductivity evaluation]
The test piece was fixed to a support, and steady heat was applied to a part of the test piece with a rubber heater preheated to 80 ° C. The state of heat diffusing from the contact area with the rubber heater to the entire test piece was measured with an infrared thermotracer (manufactured by NEC Sanei, Thermoscanner TS5304), and the in-plane thermal conductivity was evaluated by the thermographic analysis shown in FIG. did. The thermal conductivity a of the test piece was evaluated according to the following criteria as a ratio of the stainless steel plate having the same shape as the test piece to the thermal conductivity b, a / b. The results are shown in Table 2.

A: a / b is 0.9 or more and 1.1 or less ○: a / b is 0.5 or more and less than 0.9 Δ: a / b is 0.3 or more and less than 0.5 ×: a / b is 0.00. Less than 3.

[Evaluation of carbon fiber]
A part of the obtained test piece is cut out, melted on a 200 ° C. hot plate to prepare a preparation, and an image obtained by an optical microscope (manufactured by KEYENCE, VHX-500) is shown in FIG. Ten fields of view of an image magnified 200 times with an optical microscope were taken, the length of each 50 was measured, the average value of the total length of 500 carbon fibers was determined, and evaluated according to the following criteria. In addition, when magnification did not match, it adjusted suitably according to fiber length. The carbon fiber was evaluated in the same manner as described above for the pellets of the heat conductive resin composition.
A: Average fiber length of 500 μm or more ○: Average fiber length of 300 μm or more and less than 500 μm Δ: Average fiber length of 100 μm or more and less than 300 μm ×: Average fiber length of less than 100 μm

[Bending characteristics]
The specimen was treated at 110 ° C. for 2 hours to crystallize and returned to room temperature, and then the bending strength and the flexural modulus were measured by a universal testing machine (5567: manufactured by Instron) in accordance with JIS K7203. . The results are shown in Table 2.

[IZOD impact strength]
The test piece was crystallized by treatment at 110 ° C. for 2 hours, and after returning to room temperature, the IZOD impact strength was measured according to JIS K7110. The results are shown in Table 2.

[Examples 2-4, 9, 10, Comparative Examples 1, 2, 5]
In place of carbon fiber (B-2), pellets were prepared and test pieces were formed in the same manner as in Example 1 except that carbon fibers B-1 and B-3 to B-9 shown in Table 1 were used. The thermal conductivity and carbon fiber were evaluated. For Example 4, the bending strength, flexural modulus, and IZOD impact strength were measured in the same manner as Example 1. The results are shown in Table 2. The images obtained by the optical microscope for Example 4 and Comparative Example 1 are shown in FIGS. 3 and 4, respectively.

[Examples 5 to 8, 11, and 12, Comparative Examples 3, 4, and 6]
Except that 75% by mass of PLA and 20% by mass of carbon fiber were used, a pellet was prepared, a test piece was molded, and thermal conductivity and carbon fiber were evaluated in the same manner as in Example 1. For Examples 5, 6, and 8, the bending strength, flexural modulus, and IZOD impact test were measured in the same manner as in Example 1. The results are shown in Table 3.

[Example 13]
As a resin component (A), PLA, a commercially available polycarbonate resin (Caliver 301-22 manufactured by Sumitomo Dow), and carbon fiber (B-5) in mass% shown in Table 4 were used, and a continuous kneading extruder and injection molding were used. A test piece was prepared in the same manner as in Example 1 except that the cylinder temperature of the machine was set to 260 ° C., and the obtained test piece was evaluated for thermal conductivity and carbon fiber. The results are shown in Table 4.
[Example 14]
As a resin component (A), PLA, a commercially available polycarbonate resin (Caliver 301-22 manufactured by Sumitomo Dow), and carbon fiber (B-5) in mass% shown in Table 4 were used, and a continuous kneading extruder and injection molding were used. A test piece was prepared in the same manner as in Example 1 except that the cylinder temperature of the machine was set to 270 ° C., and the obtained test piece was evaluated for thermal conductivity and carbon fiber. The results are shown in Table 4.

  From the results, an image obtained by an optical microscope was used in Example 4, in which an average fiber length of the carbon fiber (B-5) was maintained at 500 μm or more, and the carbon fiber (B-2) having high crystallinity was used. From Example 1, it can be seen that the crushing of carbon fibers is suppressed.

In Comparative Examples 1, 3, 5, and 6 using carbon fibers having an average layer surface spacing (d ₀₀₂ ) of less than 0.3367 nm, the carbon fibers have high crystallinity, and the carbon fibers have an average fiber length of 100 μm during continuous kneading extrusion and injection molding. It can be seen that a network structure between carbon fibers is hardly formed, the in-plane thermal conductivity is low, and the thermal resistance is remarkably increased. On the other hand, in Comparative Examples 2 and 4 in which carbon fibers having an average layer surface spacing (d ₀₀₂ ) of 0.3440 nm are used, the carbon fibers have an average fiber length of 500 μm or more, and fiber breakage is suppressed. It can be seen that the thermal conductivity of the resin component (A) cannot be improved because the thermal conductivity of the resin component (A) cannot be improved.

On the other hand, in Examples 1 to 14 using carbon fibers having an average layer surface spacing (d ₀₀₂ ) of 0.3367 nm or more and less than 0.3440, it can be seen that the thermal conductivity is excellent even if the resin components are different.

Claims (24)

A heat conductive resin composition comprising a resin component (A) as a base material, an organic compound (E) incompatible with the resin component, and carbon fibers (B), wherein the carbon fibers (B) are X-rays A thermally conductive resin composition, wherein an average layer surface spacing (d ₀₀₂ ) of (002) planes determined by diffraction is 0.3367 nm or more and less than 0.3440 nm. 2. The heat conductive resin according to claim 1, wherein the average layer spacing (d ₀₀₂ ) of the (002) plane obtained by X-ray diffraction of the carbon fiber (B) is 0.3390 nm or more and less than 0.3440 nm. Composition.   The thermally conductive resin composition according to claim 1 or 2, wherein the crystallite size Lc in the C-axis direction of the carbon fiber (B) is 10 nm or more and 35 nm or less.   The thermally conductive resin composition according to claim 3, wherein the crystallite size Lc in the C-axis direction of the carbon fiber (B) is 10 nm or more and 20 nm or less.   The heat conductive resin composition according to any one of claims 1 to 4, wherein the carbon fiber (B) has an average fiber length of 0.1 mm to 50 mm.   The heat conductive resin composition according to any one of claims 1 to 5, wherein the carbon fiber (B) has an average diameter of 1 µm to 50 µm.   Carbon fiber (B) has an aspect ratio of 10 or more and 50000 or less, The heat conductive resin composition in any one of Claim 1 to 6 characterized by the above-mentioned.   The heat conductive resin composition according to any one of claims 1 to 7, wherein the carbon fiber (B) is contained in an amount of 1 to 40% by mass with respect to the total mass.   The heat conductive resin composition according to any one of claims 1 to 8, wherein the carbon fibers (B) are pitch-based carbon fibers.   The heat conductive resin composition according to any one of claims 1 to 9, wherein the organic compound (E) has an average particle size in a range of 0.1 µm to 500 µm.   The heat conductive resin composition according to any one of claims 1 to 10, wherein the organic compound (E) is a low molecular weight compound having a molecular weight of 2000 or less.   The organic compound (E) includes one or more selected from an ester compound, an olefin compound, a carbonate compound, and an amide compound, and has a melting point of 80 ° C or higher and 200 ° C or lower. The heat conductive resin composition in any one of.   The heat according to any one of claims 1 to 12, wherein the organic compound (E) contains one or more selected from vegetable oils and fats, animal oils and fats, and substances synthesized therefrom. Conductive resin composition.   The organic compound (E) has an aliphatic carboxylic acid amide, an aromatic carboxylic acid amide having a main chain having 8 to 44 carbon atoms, a molecular weight of 300 to 1000 and optionally having a polar group, The heat conductive resin composition according to any one of claims 1 to 13, comprising one or more selected from aliphatic carboxylic acid esters and aromatic carboxylic acid esters.   The heat conductive resin composition according to claim 14, wherein the polar group contains one or more selected from an oxygen-containing group and a nitrogen-containing group.   The heat conductive resin composition according to any one of claims 13 to 15, wherein the organic compound (E) contains a carboxylic acid amide compound derived from castor oil.   The organic compound (E) contains ricinoleic acid amide, stearic acid amide, oleic acid amide, palmitic acid amide, linoleic acid amide, linolenic acid amide, arachidic acid amide, or a derivative thereof. The heat conductive resin composition in any one of 16.   18. The heat conductive resin composition according to claim 1, wherein the organic compound (E) is contained in an amount of 0.5% by mass to 20% by mass with respect to the total mass.   The heat conductive resin composition according to any one of claims 1 to 18, wherein the resin component (A) contains one or more selected from polystyrene resins and polyester resins.   The resin component (A) is selected from polylactic acid, polycaprolactone, polybutylene succinate, polyhydroxyalkanoate, cellulose acetate, starch resin, derivatives thereof, and alloys with these petroleum polyester resins or The thermally conductive resin composition according to claim 1, comprising two or more kinds.   The thermally conductive tree composition according to any one of claims 1 to 20, wherein the resin component (A) contains one or more of polylactic acid, a polylactic acid derivative and a polylactic acid alloy.   It is a manufacturing method of the heat conductive resin composition in any one of Claim 1 to 21, Comprising: Supplying and mixing carbon fiber (B) to the molten resin component (A) and organic compound (E). The manufacturing method of the heat conductive resin composition characterized by the above-mentioned.   A thermally conductive resin molded article, which is molded using the thermally conductive resin composition according to any one of claims 1 to 21.   The thermally conductive resin molded article according to claim 23, which is molded by injection molding.