JP2011184618A - Molded product consisting of electroconductive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molded product which consists of an electroconductive resin composition having conductivity, low dusting nature, flowability, and especially generating little volatile organic gas, the electroconductive resin composition having excellent mechanical characteristics, especially weld strength retention while retaining the characteristics. <P>SOLUTION: The molded product consists of the electroconductive resin composition containing 1-20 pts.wt. of a conductive carbon material (component C) and 0.1-10 pts.wt. of a hydrogenation styrenic thermoplastic elastomer (component D) having a styrene content of 20-40 wt.%, based on 100 pts.wt. of a resin component which consists of 51-95 wt.% of aromatic polycarbonate resin (component A) and 5-49 wt.% of polyethylene terephthalate resin (component B), wherein the surface resistivity of the molded product is 10<SP>12</SP>Ω/sq or less and a half-attenuation time is 10 s or less when 10 kV is impressed. The molded products consisting of the electroconductive resin composition are selected from the group consisting of electric and electronic parts, OA equipment parts, semiconductor related members and automobile exterior parts. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a molded article made of a conductive resin composition. More specifically, the present invention has good electrical conductivity and rapid voltage decay characteristics, and the conductive carbon material does not fall off from the resin surface of the molded product, and the amount of volatile organic gas from the molded product is small. Furthermore, in addition to excellent fluidity, the present invention relates to a molded product selected from the group consisting of electrical and electronic parts, OA equipment parts, semiconductor-related members and automobile exterior parts, which are excellent in mechanical properties, particularly weld strength.

With the progress of miniaturization and weight reduction, higher integration, and higher precision of OA equipment and electronic equipment in hard disk-related parts and semiconductor-related members exemplified by in-process containers, IC chip trays, wafer transfer containers, glass containers, etc. Demands for reducing dust and dust adhesion in related processes and preventing malfunction due to static electricity failures of OA equipment and electronic equipment are becoming stricter year by year. In order to prevent malfunction due to static electricity failure, the surface resistivity of the components around the hard disk is set to 10 ⁵ to 10 ¹² Ω so as to prevent dust and dust from adhering around the hard disk and to prevent static electricity that is the basis of the failure. It is customary to control to / sq and to quickly decay the charged voltage. In addition, electrical and electronic parts such as camera shutter parts such as shutter base plates, shutter blade retainers, and intermediate plates incorporated in cameras, etc., may be malfunctioned if charged even a little due to friction during their operation. It is necessary to control the surface resistivity of peripheral components to 10 ¹² Ω / sq or less and to quickly attenuate the charged voltage. Moreover, electrostatic coating is generally performed on automobile exterior parts in order to improve the adhesion efficiency of paint. Electrostatic coating uses a grounded coating as an anode and a coating atomizer as a cathode. A negative high voltage is applied to this to create an electrostatic field between the two electrodes, and the atomized coating particles are charged negatively. This is a coating method in which a paint is efficiently adsorbed on an object that is the opposite pole. Since thermoplastic resin is electrically insulating, it is necessary to add conductivity to perform electrostatic coating. To obtain high conductivity with a small amount of conductive material, a conductive carbon material should be added. Is widely practiced.

  Compared to the above products, the products are becoming smaller, lighter, more integrated, and more accurate, and in addition to the antistatic function to prevent adhesion, the dust generated from the parts, so-called conductive carbon material is removed. The requirements for reducing dust and dust adhesion in related processes, such as the requirements for materials, and the operating noise due to trace amounts of corrosive organic gas are becoming stricter year by year. In addition, since the miniaturization or thinning is progressing, the resin composition used in such a molded product is desired to have higher fluidity, and depending on the shape of the molded product, the molded product may be formed at the time of mold release. Since such load tends to increase, stronger mechanical strength is required.

  It is known to blend a conductive carbon material into an alloy of an aromatic polycarbonate and a thermoplastic polyalkylene phthalate, and in Patent Document 1, by blending a thermoplastic polyalkylene phthalate into an aromatic polycarbonate and a conductive carbon black, The dispersibility of carbon black is improved without impairing the mechanical properties, moldability, and conductivity of the polycarbonate resin. However, in the alloy of polycarbonate and polyethylene terephthalate, it is generally known that the adhesion at the interface is poor and the weld strength and impact strength are reduced. Unable to meet increasing mechanical strength requirements. In Patent Document 2, conductive carbon black is blended with an alloy of aromatic polycarbonate and polyethylene terephthalate in order to provide a conductive resin composition excellent in impact resistance, dimensional stability, fluidity, appearance, and the like. In addition, it is proposed that the dispersion of the conductive carbon black is unevenly distributed in the polyethylene terephthalate phase, and the inclusion of a rubbery polymer is recommended in order to improve the impact resistance. Further, Patent Document 3 proposes a conductive resin composition having a low surface glossiness by blending conductive carbon black with an alloy of aromatic polycarbonate and polyethylene terephthalate and further blending a styrene elastomer. . However, in these patent documents, the surface resistivity of the molded article is exemplified, but this is a usual countermeasure against static electricity trouble, and as the miniaturization and weight reduction of the members, higher integration, and higher accuracy are progressing, It is not enough to meet user demands for severe electrostatic disturbances. At present, it is necessary to keep the spark current small so that a precision component does not break even if a spark occurs. Further, the dropping of the conductive carbon material from the resin surface of the molded product and the generation of corrosive organic gas have been problems, and in particular, a rubber polymer commonly known for improving impact resistance is used. In the compounding, a large amount of corrosive organic gas is generated, so that there is a limit to the application to applications that require a high level of static electricity countermeasures and high cleanliness.

Japanese Patent No. 3897512 JP 2005-120323 A JP 2008-184482 A

  The object of the present invention is to have good electrical conductivity and quick voltage decay characteristics, a small spark current generated from the surface of the molded product, a small drop of the conductive carbon material from the resin surface of the molded product, and from the molded product. From the group consisting of electrical and electronic parts, OA equipment parts, semiconductor-related parts, and automotive exterior parts, which have low volatile organic gas content and excellent fluidity, as well as excellent mechanical properties, particularly weld strength. The purpose is to provide the selected molded product.

In order to solve the above-mentioned problems, the present inventors have intensively studied to complete the present invention. That is, the present inventors made conductive carbon material (C) with respect to 100 parts by weight of resin component consisting of 51 to 95% by weight (A component) of aromatic polycarbonate resin and 5 to 49% by weight (B component) of polyethylene terephthalate resin. 1) to 20 parts by weight of component) and 0.1 to 10 parts by weight of hydrogenated styrene-based thermoplastic elastomer (component D) having a styrene content of 20 to 40% by weight, an OA equipment part, A molded product selected from the group consisting of a semiconductor-related member and an automobile exterior part, wherein the molded product has a surface resistivity of 10 ¹² Ω / sq or less and a half decay time of 10 seconds or less when 10 kV is applied. A certain molded product has a reduced spark current, which is one of the electrostatic disturbances, has good conductivity and rapid voltage decay characteristics, and is a conductive carbon material from the resin surface of the molded product. The present invention was completed by finding that the mechanical properties, in particular, the weld strength were good while maintaining a small amount of volatile organic gas from the molded product, and also having excellent fluidity. .

  The mechanism by which the spark current is reduced is considered to be that the spark current is reduced because the conductive carbon material is finely dispersed on the resin surface of the molded product and the static electricity accumulated in the resin quickly moves to the conductive carbon material. The spark current can be measured by a method in which a terminal is brought close to a molded product to which a high voltage is applied by an electric field induction method and the spark current is measured, and is a method based on the JEDEC standard (JESD22-C1010C). The removal of the conductive carbon material from the resin surface of the molded product can be suppressed by blending polyethylene terephthalate because the conductive carbon material is unevenly distributed only in polyethylene terephthalate, and the familiarity between the surface of the conductive carbon material and polyethylene terephthalate. It is thought to be good.

  The reason why it is possible to improve the mechanical properties, particularly the weld strength, while maintaining good electrical conductivity and rapid voltage decay characteristics, less conductive carbon material falling off and good fluidity, is that styrene content is 20-40% by weight of hydrogenated styrene thermoplastic elastomer has good compatibility with polycarbonate resin and polyethylene terephthalate resin, which affects the phase structure of polyethylene terephthalate resin containing polycarbonate resin and conductive carbon material. This is considered to be because the strength of the interface can be improved without reaching. Further, among the styrene-based thermoplastic elastomers, the use of a hydrogenated styrene-based thermoplastic elastomer having excellent heat resistance eliminates an increase in the generation of volatile organic gas from the molded product.

  The molded article made of the resin composition of the present invention has good conductivity and rapid voltage decay characteristics, and the conductive carbon material does not fall off from the resin surface of the molded article, and the volatile organic gas from the molded article. In addition to its small amount and excellent fluidity, it has excellent mechanical properties, particularly weld strength, and is therefore useful for electrical and electronic parts, OA equipment parts, semiconductor-related parts, automobile exterior parts, and the like.

<Component A: aromatic polycarbonate>
An aromatic polycarbonate (component A) is obtained by reacting a dihydric phenol and a carbonate precursor. Examples of the reaction method include an interfacial polycondensation method, a melt transesterification method, a solid phase transesterification method of a carbonate prepolymer, and a ring-opening polymerization method of a cyclic carbonate compound.

  Representative examples of the dihydric phenol used here include hydroquinone, resorcinol, 4,4′-biphenol, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis (4-hydroxyphenyl). ) Propane (commonly called bisphenol A), 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl)- 1-phenylethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis (4-hydroxyphenyl) Pentane, 4,4 ′-(p-phenylenediisopropylidene) diphenol, 4,4 ′-(m-phenylenediisopropyl Pyridene) diphenol, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) ketone, bis (4-hydroxyphenyl) ester, bis (4-hydroxy-3-methylphenyl) sulfide, 9,9-bis (4-hydroxyphenyl) Examples include fluorene and 9,9-bis (4-hydroxy-3-methylphenyl) fluorene. A preferred dihydric phenol is bis (4-hydroxyphenyl) alkane, and bisphenol A (hereinafter sometimes abbreviated as “BPA”) is particularly preferred because of its excellent toughness, and is widely used.

  As the carbonate precursor, carbonyl halide, carbonic acid diester, haloformate or the like is used, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like.

  In producing a polycarbonate resin by interfacial polymerization of the above dihydric phenol and carbonate precursor, a catalyst, a terminal terminator, an antioxidant for preventing the dihydric phenol from being oxidized, etc., as necessary. May be used. The polycarbonate resin of the present invention is a branched polycarbonate resin copolymerized with a trifunctional or higher polyfunctional aromatic compound, or a polyester carbonate resin copolymerized with an aromatic or aliphatic (including alicyclic) difunctional carboxylic acid. , Copolymerized polycarbonate resins copolymerized with bifunctional alcohols (including alicyclic), and polyester carbonates copolymerized with such bifunctional carboxylic acids and difunctional alcohols. Moreover, the mixture which mixed 2 or more types of the obtained polycarbonate may be sufficient.

  The branched polycarbonate increases the melt tension of the resin composition of the present invention, and can improve the molding processability in extrusion molding, foam molding and blow molding based on such properties. As a result, a molded product by these molding methods, which is superior in dimensional accuracy, is obtained.

  Examples of the trifunctional or higher polyfunctional aromatic compound used in the branched polycarbonate resin include 4,6-dimethyl-2,4,6-tris (4-hydroxydiphenyl) heptene-2, 2,4,6- Trimethyl-2,4,6-tris (4-hydroxyphenyl) heptane, 1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1 , 1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, and 4- {4- [1,1- Trisphenol such as bis (4-hydroxyphenyl) ethyl] benzene} -α, α-dimethylbenzylphenol is preferably exemplified. Other polyfunctional aromatic compounds include phloroglucin, phloroglucid, tetra (4-hydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) ketone, 1,4-bis (4,4-dihydroxytriphenylmethyl) benzene. And trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, and acid chlorides thereof. Of these, 1,1,1-tris (4-hydroxyphenyl) ethane and 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane are preferable, and 1,1,1-tris (4- Hydroxyphenyl) ethane is preferred.

  The structural unit derived from the polyfunctional aromatic compound in the branched polycarbonate is 0.1% in a total of 100 mole parts of the structural unit derived from the dihydric phenol and the structural unit derived from the polyfunctional aromatic compound. It is 03-1 mol part, Preferably it is 0.07-0.7 mol part, Most preferably, it is 0.1-0.4 mol part.

Further, such a branched structural unit is not only derived from a polyfunctional aromatic compound but also derived without using a polyfunctional aromatic compound, such as a side reaction during a melt transesterification reaction. Also good. The ratio of such a branched structure can be calculated by ¹ H-NMR measurement.

  On the other hand, the aliphatic bifunctional carboxylic acid is preferably α, ω-dicarboxylic acid, and specific examples thereof include sebacic acid (decanedioic acid), dodecanedioic acid, tetradecanedioic acid, octadecanedioic acid, icosane diacid. Examples thereof include linear saturated aliphatic dicarboxylic acids such as acids and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. As the bifunctional alcohol, an alicyclic diol is suitable, and examples thereof include cyclohexanedimethanol, cyclohexanediol, and tricyclodecane dimethanol. Further, a polycarbonate-polyorganosiloxane copolymer obtained by copolymerizing polyorganosiloxane units can also be used.

  The component A may be a mixture of two or more of polycarbonates having different dihydric phenol components, polycarbonates containing branched components, various polyester carbonates, polycarbonate-polyorganosiloxane copolymers, and the like. Furthermore, what mixed 2 or more types of polycarbonates from which a manufacturing method differs, a polycarbonate from which a terminal terminator differs, etc. can also be used. Reaction formats such as interfacial polymerization, melt transesterification, solid phase transesterification of carbonate prepolymers, and ring-opening polymerization of cyclic carbonate compounds, which are methods for producing the aromatic polycarbonate of the present invention, are various documents and patents. This is a well-known method in gazettes.

  As the A component aromatic polycarbonate of the present invention, not only a virgin raw material but also an aromatic polycarbonate regenerated from a used product, that is, a so-called material recycled aromatic polycarbonate can be used. Used products include soundproof walls, glass windows, translucent roofing materials, various glazing materials represented by automobile sunroofs, transparent members such as windshields and automobile headlamp lenses, containers such as water bottles, and optical recording media Etc. are preferred. These do not contain a large amount of additives or other resins, and the desired quality is easily obtained stably. In particular, an automotive headlamp lens, an optical recording medium, and the like are preferred as preferred embodiments because they satisfy the more preferable conditions of the viscosity average molecular weight. In addition, said virgin raw material is a raw material which is not yet used in the market after the manufacture.

Since the surface resistivity in the molded article of the present invention may be greatly affected by the fluidity of the resin composition, a method for controlling the fluidity can be taken as one of the adjustment methods. The viscosity average molecular weight of the aromatic polycarbonate is preferably 1 × 10 ^{4 to} 5 × 10 ⁴ , more preferably 1.4 × 10 ^{4 to} 3 × 10 ⁴ , and still more preferably 1.8 × 10 ^{4 to} 2.5 ×. 10 is ^four. In the range of 1 × 10 ^{4 to} 5 × 10 ⁴ , both excellent impact resistance and fluidity are particularly excellent, and it is easy to adjust the surface resistivity of the molded product made of the resin composition to the conductive region. It becomes. Most preferably, it is 1.9 × 10 ^{4 to} 2.4 × 10 ⁴ . The viscosity average molecular weight may be satisfied as the whole component A, and includes those satisfying such a range by a mixture of two or more kinds having different molecular weights.

The viscosity average molecular weight referred to in the present invention is first determined by using an Ostwald viscometer from a solution in which 0.7 g of aromatic polycarbonate is dissolved in 100 ml of methylene chloride at 20 ° C., and the specific viscosity calculated by the following formula:
Specific viscosity (η _SP ) = (t−t ₀ ) / t ₀
[T ₀ is methylene chloride falling seconds, t is sample solution falling seconds]
The obtained specific viscosity is inserted by the following equation to determine the viscosity average molecular weight M.
η _SP /c=[η]+0.45×[η] ² c (where [η] is the intrinsic viscosity)
[Η] = 1.23 × 10 ⁻⁴ M ^0.83
c = 0.7

<B component: polyethylene terephthalate>
Polyethylene terephthalate (component B) is a saturated polyester polymer or copolymer obtained by a condensation reaction of terephthalic acid as an aromatic dicarboxylic acid component and ethylene glycol as a diol component. Yes, it is a thermoplastic polyester resin containing ethylene terephthalate units as repeating units, preferably 70 mol% or more, more preferably 80 mol% or more. According to a conventional method, the polyethylene terephthalate resin is produced by reacting the dicarboxylic acid component and the diol component with heating in the presence of a polycondensation catalyst containing titanium, germanium, antimony, etc. It is performed by discharging alcohol out of the system. For example, germanium-based polymerization catalysts include germanium oxides, hydroxides, halides, alcoholates, phenolates, and the like. More specifically, germanium oxide, germanium hydroxide, germanium tetrachloride, tetramethoxygermanium, etc. Can be illustrated. At this time, either a batch method or a continuous polymerization method can be employed, and the degree of polymerization can be increased by solid phase polymerization.

  Moreover, the terminal group structure of the polyethylene terephthalate to be used is not particularly limited, and may be a case where the ratio of one of the hydroxyl groups and the carboxyl group in the terminal group is large other than the case where the ratio is almost the same. Moreover, those terminal groups may be sealed by reacting a compound having reactivity with such terminal groups.

  Further, in the present invention, compounds such as manganese, zinc, calcium, magnesium, etc., which are used in a transesterification reaction that is a prior stage of a conventionally known polycondensation, can be used in combination, and phosphoric acid or phosphorous after completion of the transesterification reaction. Such a catalyst can be deactivated and polycondensed with an acid compound or the like.

  Further, the molecular weight of polyethylene terephthalate (component B) is not particularly limited, but in order to obtain a suitable fluidity for controlling the surface resistivity of the molded article made of the resin composition, o-chlorophenol is used as a solvent. The intrinsic viscosity measured at ° C is preferably 0.4 to 1.2, more preferably 0.65 to 1.15.

The content of the polyethylene terephthalate (component B) is 5 to 49% by weight, preferably 10 to 45% by weight, more preferably 15 to 45% by weight per 100% by weight in total with the aromatic polycarbonate (component A). Preferably, 20 to 45% by weight is most preferable. By blending polyethylene terephthalate, the conductive carbon material is unevenly distributed in the polyethylene terephthalate phase, and therefore conductivity can be obtained with a smaller amount of the conductive carbon material added. However, if the blending ratio of polyethylene terephthalate is less than 5% by weight, the blending amount of polyethylene terephthalate is so small that it is impossible to prevent the conductive carbon material from falling off. If it exceeds 49% by weight, the conductive carbon material of the polyethylene terephthalate phase is diluted, the surface resistivity becomes larger than 10 ¹² Ω / sq, and dust and dust are likely to adhere to the surface of the molded product, which is not preferable.

<C component: conductive carbon material>
The conductive carbon material (component C) is blended to impart conductivity to the resin composition and to control the surface resistivity and charging half decay time of a molded product made of the conductive resin composition.
Examples of conductive carbon materials include carbon black, carbon nanotubes, amorphous carbon, graphite, fibrous carbon, and nanocarbon. Among these, outgas, surface finish and gloss, fluidity, spark current, etc. Therefore, conductive carbon black and carbon nanotubes are preferable.

(Conductive carbon black)
Examples of the conductive carbon black include ketjen black, acetylene black, furnace black, thermal black, etc. Among them, the conductive carbon black exhibits excellent conductivity in a very small amount compared to the conventional conductive carbon black, and a small amount Ketjen black is preferable in that excellent conductivity can be obtained by addition.

This conductive carbon black is not particularly limited by the raw material and the production method, but carbon black having a DBP oil absorption of 400 ml / 100 g or more and a BET specific surface area of 1000 m ² / g or more can be used more suitably. . The DBP oil supply amount is more preferably 400 to 1000 ml / 100 g, further preferably 400 to 600 ml / 100 g. When the DBP oil absorption is smaller than 400 ml / 100 g and the BET specific surface area is smaller than 1000 m ² / g, or when either the DBP oil absorption is 400 ml / 100 g or the BET specific surface area is 1000 m ² / g smaller than the above value In order to obtain a desired surface resistivity and charged voltage half decay time, a larger amount of blending is required, and as a result, there is a possibility that the conductive carbon material is dropped and the fluidity is lowered. Moreover, there is no restriction | limiting in particular about the upper limit of a BET specific surface area, However, 1500 m < ² > / g or less is more preferable at the point which may impair workability | operativity greatly.

  Here, the DBP oil absorption is a value measured by a dibutyl phthalate abstract meter, which is the ml capacity of dibutyl phthalate contained per 100 g of conductive carbon black, and indicates the degree of structure of the conductive carbon black. It is said to affect the conductivity when blended with the composition. Further, the BET specific surface area is a value obtained by a liquid nitrogen adsorption method and indicates the surface area per unit weight of the conductive carbon black.

(carbon nanotube)
The carbon nanotube is not particularly limited by the raw material and the manufacturing method, but the number of graphene sheets may be one layer, two layers, or a plurality of layers exceeding two layers, particularly a plurality of layers exceeding two layers. Is preferred. The diameter of the carbon nanotube is preferably 0.7 to 100 nm, more preferably 7 to 100 nm, and still more preferably 15 to 90 nm. The aspect ratio of the carbon nanotube is preferably 5 or more, more preferably 50 or more, and still more preferably 100 or more.

  The aspect ratio can be determined from the ratio of length and diameter measured at a scanning electron microscope magnification of 3 to 100,000. The length is measured by the following method. First, the observation image is taken into the CCD camera as image data. Next, the fiber length of the obtained image data is calculated using an image analyzer. The number of measurement is 5000 or more. The diameter is measured by the following method. First, carbon nanotubes whose diameter is to be measured are randomly extracted from an image obtained by observation with an electron microscope, and the diameter is measured near the center. If the cross section is not a circle, the maximum value is the diameter. The number average diameter is calculated from the measured values obtained. Since recent electron microscopes have a function of calculating the length on the observation screen, the diameter can be calculated relatively easily. The number of measurement is 1000 or more.

  Content of this electroconductive carbon material (C component) is 1-20 weight part with respect to a total of 100 weight part of a resin component, 2-15 weight part is preferable and 3-10 weight part is more preferable. If the blending amount of the conductive carbon material is less than 1 part by weight, the surface resistivity and the charged voltage decay time do not fall within the scope of the present invention, and if the blending amount of the conductive carbon material exceeds 20 parts by weight, the conductivity is increased. It is not preferable because the carbon material is largely dropped.

<D component: hydrogenated styrene thermoplastic elastomer>
The hydrogenated styrenic thermoplastic elastomer used in the present invention is blended to improve the interfacial strength between the polycarbonate resin and the polyethylene terephthalate resin, and has excellent heat resistance. Occurrence is suppressed. The styrene content of the elastomer is 20 to 40% by weight, preferably 23 to 37% by weight, and more preferably 25 to 35% by weight. When the styrene content is outside the range of 20 to 40% by weight, the compatibility is deteriorated and the effect of improving the strength is lowered, which is not desirable. This is because such an elastomer needs to improve the interfacial strength while maintaining the phase structure of the polycarbonate resin and the polyethylene terephthalate resin so as not to affect the electrical properties. From the viewpoint of compatibility, it is preferable that both ends of the hard block are styrene components, and the soft block has a polyolefin structure such as polybutylene and polyisoprene, which have a high effect of improving the strength.

  Specific examples of the hydrogenated styrene thermoplastic elastomer include styrene-hydrogenated polybutadiene-styrene copolymer (SEBS), styrene-hydrogenated polyisoprene-styrene copolymer (SEPS), styrene-hydrogenated poly (isoprene / And butadiene) -styrene copolymer (SEEPS). Of these, styrene-hydrogenated polyisoprene-styrene copolymer (SEPS) and styrene-hydrogenated poly (isoprene / butadiene) -styrene copolymer (SEEPS), which are more excellent in heat resistance, are preferable, and among them, styrene-water. An additive poly (isoprene / butadiene) -styrene copolymer (SEEPS) is more preferable.

  The content of the styrenic thermoplastic elastomer (component D) is 0.1 to 10 parts by weight, preferably 1 to 8 parts by weight, and more preferably 1 to 6 parts by weight with respect to 100 parts by weight of the total resin component. preferable. If the amount is less than 0.1 weight, such a sufficient improvement effect of the interfacial strength cannot be obtained, and if the amount exceeds 10 parts by weight, the amount of volatile organic gas generated is undesirably increased.

<E component: polytetrafluoroethylene particles>
The polytetrafluoroethylene particles used in the present invention are blended in order to impart slidability to the molded product and to prevent the conductive carbon material from falling off.
The polytetrafluoroethylene particles of the present invention include low molecular weight polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / perfluoromethyl vinyl ether copolymer, tetrafluoroethylene / hexafluoropropylene copolymer, tetrafluoroethylene / An ethylene copolymer or the like can be mentioned, and any of these can be used, but among them, the use of low molecular weight polytetrafluoroethylene is preferable from the viewpoint of slidability. The low molecular weight polytetrafluoroethylene includes those containing a small amount of a copolymer component. As the low molecular weight polytetrafluoroethylene, those usually used as dry lubricants can be used, and preferably in the form of fine powder. The average particle diameter of the fine powder is preferably 0.1 to 100 μm by a method of measuring a dispersion dispersed in perchlorethylene by a light transmission method. The melting point of the polytetrafluoroethylene fine powder is preferably 320 ° C. or higher as measured by DSC method. Since the polytetrafluoroethylene fine powder is easily re-agglomerated, some of it has been subjected to a treatment such as a baking treatment in order to make it difficult to re-agglomerate, and these can be preferably used. Polytetrafluoroethylene resin is Lubron L-5, L-2, L-7 from Daikin Industries, Ltd., and Fullon L-150J, L-169J, L-170J, L from Asahi IC Fluoropolymers Co., Ltd. It is commercially available as -172J, as TLP-10F-1 from Mitsui DuPont Fluorochemical Co., Ltd., and as Hostaflon TF9202 and TF9205 from Hoechst Japan Co., Ltd.

  Such polytetrafluoroethylene particles are preferably blended in an amount of 1 to 10 parts by weight, more preferably 1 to 5 parts by weight, per 100 parts by weight of the total of component A and component B. If the amount is less than 1 weight, the desired slidability cannot be obtained, so that the dropping of the conductive carbon material cannot be sufficiently suppressed. If the amount exceeds 10 parts by weight, the polytetrafluoroethylene dispersed phase causes the conductive path of the conductive carbon material. This may adversely affect the surface resistivity and the half voltage decay time of the molded product.

<F component: Stabilizer>
The stabilizer (component F) is preferably at least one selected from the group consisting of phosphite compounds, phosphonite compounds, hindered phenol compounds and thioether compounds. Among these, at least one stabilizer selected from the group consisting of a phosphite compound and a hindered phenol compound having little influence on the generation of volatile organic gas is particularly preferable.

(Phosphite compounds)
As phosphite compounds, triphenyl phosphite, tris (nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl Phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, tris (diethylphenyl) phosphite, tris (di-iso-propylphenyl) phosphite, tris (di-n-butylphenyl) Phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, distearyl pentaeri Ritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis ( 2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite, phenylbisphenol A penta Examples include erythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, and dicyclohexylpentaerythritol diphosphite.

  Furthermore, as other phosphite compounds, those that react with dihydric phenols and have a cyclic structure can be used. For example, 2,2′-methylenebis (4,6-di-tert-butylphenyl) (2,4-di-tert-butylphenyl) phosphite, 2,2′-methylenebis (4,6-di-tert- Butylphenyl) (2-tert-butyl-4-methylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, and the like.

  Suitable phosphite compounds are distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methyl). Phenyl) pentaerythritol diphosphite, and bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite.

(Phosphonite compounds)
Examples of phosphonite compounds include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylene diphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenylene diphospho. Knight, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,4'-biphenylenediphosphonite, Tetrakis (2,6-di-tert-butylphenyl) -4,3′-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -3,3′-biphenylenediphosphonite, bis ( 2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite, bis (2,4-di-tert Butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-n-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) -4- Examples thereof include phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) -3-phenyl-phenylphosphonite. Tetrakis (di-tert-butylphenyl) -biphenylenediphosphonite, bis (di-tert-butylphenyl) -phenyl-phenylphosphonite are preferred, and tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite Knight and bis (2,4-di-tert-butylphenyl) -phenyl-phenylphosphonite are more preferred. Such a phosphonite compound can be used in combination with a phosphite compound having an aryl group in which two or more alkyl groups are substituted.

  The phosphonite compound is preferably tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite, and stabilizers based on the phosphonite are Sandostab P-EPQ (trademark, manufactured by Clariant) and Irgafos P. -It is commercially available as EPQ (trademark, manufactured by CIBA SPECIALTY CHEMICALS) and any of them can be used.

(Hindered phenolic compounds)
As the hindered phenol compound, various compounds usually blended in a resin can be used. Examples of such hindered phenol compounds include α-tocopherol, butylhydroxytoluene, sinapyl alcohol, vitamin E, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2-tert-butyl. -6- (3'-tert-butyl-5'-methyl-2'-hydroxybenzyl) -4-methylphenyl acrylate, 2,6-di-tert-butyl-4- (N, N-dimethylaminomethyl) Phenol, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6) -Tert-butylphenol), 4,4'-methylenebis (2,6-di-t) rt-butylphenol), 2,2′-methylenebis (4-methyl-6-cyclohexylphenol), 2,2′-dimethylene-bis (6-α-methyl-benzyl-p-cresol), 2,2′-ethylidene -Bis (4,6-di-tert-butylphenol), 2,2'-butylidene-bis (4-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol) ), Triethylene glycol-N-bis-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 1,6-hexanediol bis [3- (3,5-di-tert- Butyl-4-hydroxyphenyl) propionate], bis [2-tert-butyl-4-methyl-6- (3-tert-butyl- -Methyl-2-hydroxybenzyl) phenyl] terephthalate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1, -dimethylethyl } -2,4,8,10-tetraoxaspiro [5,5] undecane, 4,4′-thiobis (6-tert-butyl-m-cresol), 4,4′-thiobis (3-methyl-6) -Tert-butylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, 4,4'-di- Thiobis (2,6-di-tert-butylphenol), 4,4′-tri-thiobis (2,6-di-tert-butylphenol), 2,2-thiodiethylene S- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis (n-octylthio) -6- (4-hydroxy-3,5-di-tert- Butylanilino) -1,3,5-triazine, N, N′-hexamethylenebis- (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N, N′-bis [3- (3 , 5-Di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl -2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl-4-hydroxyphenyl) isocyanur Rate, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 1,3,5-tris2 [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanurate, tetrakis [methylene-3- (3,5-di-tert-butyl- 4-hydroxyphenyl) propionate] methane, triethylene glycol-N-bis-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, triethylene glycol-N-bis-3- (3- tert-butyl-4-hydroxy-5-methylphenyl) acetate, 3,9-bis [2- {3 (3-tert-butyl-4-hydroxy-5-methylphenyl) acetyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, tetrakis [methylene- 3- (3-tert-Butyl-4-hydroxy-5-methylphenyl) propionate] methane, 1,3,5-trimethyl-2,4,6-tris (3-tert-butyl-4-hydroxy-5- Examples include methylbenzyl) benzene and tris (3-tert-butyl-4-hydroxy-5-methylbenzyl) isocyanurate.

  Among the above compounds, tetrakis [methylene-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] methane, octadecyl-3- (3,5-di-tert-butyl-) is used in the present invention. 4-hydroxyphenyl) propionate, and 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4 , 8,10-Tetraoxaspiro [5,5] undecane is preferably used. In particular, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxa Spiro [5,5] undecane is preferred. The said hindered phenol type compound can be used individually or in combination of 2 or more types.

(Thioether compounds)
Specific examples of thioether compounds include dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol-tetrakis (3-lauryl thiopropionate), Pentaerythritol-tetrakis (3-dodecylthiopropionate), pentaerythritol-tetrakis (3-octadecylthiopropionate), pentaerythritol tetrakis (3-myristylthiopropionate), pentaerythritol-tetrakis (3-stearylthio) Propionate) and the like.

  The content of the stabilizer (component F) is preferably 0.001 to 2 parts by weight, more preferably 0.005 to 1 part by weight, still more preferably 0.001 part by weight per 100 parts by weight of the total of component A and component B. 01 to 0.5 parts by weight. When the blending amount is less than 0.001 part by weight, the stability effect is insufficient, so the residence heat stability is lowered, and when it exceeds 2 parts by weight, the stability effect is lowered, and also due to the volatile matter derived from the stabilizer. The amount of gas generated increases, which may impair the cleanliness of the molded product.

<Other additives>
The composition of the present invention includes other thermoplastic resins (for example, polyarylate resin, liquid crystalline polyester resin, polyamide resin, polyimide resin, polyether, excluding component A and component B within the range where the effects of the present invention are exhibited. Imide resin, polyurethane resin, silicone resin, polyphenylene ether, polyphenylene sulfide resin, polysulfone resin, polyolefin resin such as polyethylene and polypropylene, polystyrene resin, acrylonitrile / styrene copolymer (AS resin), acrylonitrile / butadiene / styrene copolymer ( ABS resin), polystyrene resin, high impact polystyrene resin, syndiotactic polystyrene resin, polymethacrylate resin, phenoxy or epoxy resin, etc.), inorganic filler (glass fiber, glass) (Lake, carbon fiber, carbon flake, talc, wollastonite, etc.), organic filler (aramid fiber, kenaf fiber, etc.), impact modifier excluding D component (core shell acrylic rubber, core shell butadiene rubber, etc.), UV Absorbers (benzotriazole, triazine, benzophenone, etc.), light stabilizers (HALS, etc.), mold release agents (saturated fatty acid esters, unsaturated fatty acid esters, paraffin wax, beeswax, etc.), flow modifiers (polycaprolactone) Colorants (carbon black, titanium dioxide, various organic dyes, metallic pigments, etc.), antistatic agents, inorganic and organic antibacterial agents, photocatalytic antifouling agents (fine particle titanium oxide, fine particle zinc oxide, etc.), You may mix | blend an infrared absorber and a photochromic agent ultraviolet absorber. These various additives can be used in known amounts.

<Manufacture of conductive resin composition>
Arbitrary methods are employ | adopted for manufacture of the conductive resin composition of this invention. For example, components A to F are sufficiently mixed (so-called dry blend) using premixing means such as a V-type blender, a Henschel mixer, a mechanochemical apparatus, and an extrusion mixer, and then an extrusion granulator as necessary. Granulation of the pre-mixture obtained by using a briquetting machine, etc., and then melt-kneading with a melt-kneader typified by a vent type twin-screw extruder, and pelletizing the melt-kneaded composition with a device such as a pelletizer The method of making it.

  In addition, a method of supplying each component independently to a melt kneader represented by a vent type twin screw extruder, or a part of each component is premixed and then supplied to the melt kneader independently of the remaining components. The method of doing is also mentioned. Examples of the premixing method include a method of dry blending a part of the powder of the component A and an additive to be blended such as the component C to prepare a master batch of the additive diluted with the powder. Furthermore, the method etc. which supply one component independently from the middle of a melt extruder are mentioned. The heating temperature at the time of melt kneading is usually selected in the range of 250 to 300 ° C.

  In addition, when there exists a liquid thing in the component to mix | blend, what is called a liquid injection apparatus or a liquid addition apparatus can be used for supply to a melt extruder. As such a liquid injection device or a liquid addition device, one provided with a heating device is preferably used.

  The extruded resin can be cut directly into pellets or formed into strands and then cut into pellets with a pelletizer. When it is necessary to reduce the influence of external dust during pelletization, it is preferable to clean the atmosphere around the extruder. Although the shape of the obtained pellet can take general shapes, such as a cylinder, a prism, and a spherical shape, it is more preferably a cylinder. The diameter of such a cylinder is preferably 1 to 5 mm, more preferably 1.5 to 4 mm, and still more preferably 2 to 3.3 mm. On the other hand, the length of the cylinder is preferably 1 to 30 mm, more preferably 2 to 5 mm, and still more preferably 2.5 to 3.5 mm.

  The conductive resin composition of the present invention preferably has a generated gas amount of 2 ppm or less, more preferably 1 ppm or less, and even more preferably 0.5 ppm or less. If the amount of generated gas exceeds 2 ppm, there is a possibility of affecting the precision parts around the molded product, which is not preferable. The generated gas amount of the resin composition was measured by the following method. That is, the amount of volatile organic gas was measured for the conductive resin composition pellets of the present invention using a gas chromatogram (GC-MS manufactured by Agilent). Specifically, 3 g of the extruded composition pellets was heated at 150 ° C. for 1 hour, the amount of volatile organic gas was measured with a gas chromatogram (GC-MS), and the total amount was converted to toluene, and the amount of gas generated It was.

<Creation of molded products>
Various products can be produced from the molded product comprising the conductive resin composition of the present invention by obtaining a molded product by injection molding the pellets produced as described above. In such injection molding, not only ordinary molding methods but also injection compression molding, injection press molding, gas assist injection molding, foam molding (including a method of injecting a supercritical fluid), insert molding, in-mold coating molding, heat insulation Examples thereof include mold molding, rapid heating / cooling mold molding, two-color molding, sandwich molding, and ultra-high speed injection molding. In addition, either a cold runner method or a hot runner method can be selected for molding. Conventionally known molding methods can be applied to the injection-molded product without any limitation, but the mold temperature is preferably 30 ° C. or higher, more preferably 40 ° C. or higher from the viewpoint of improving the appearance during injection molding. However, the mold temperature is preferably 100 ° C. or lower, more preferably 90 ° C. or lower in the sense of preventing the deformation of the molded product. Moreover, the molded article which consists of the conductive resin composition of this invention can also be obtained by extrusion molding, rotational molding, blow molding, etc.

Furthermore, the molded article made of the conductive resin composition of the present invention can be imparted with other functions by surface modification. Surface modification here means a new layer on the surface of resin molded products such as vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), plating (electroplating, electroless plating, hot dipping, etc.), painting, coating, printing, etc. The method used for normal resin molded products can be applied.
Applications of the molded article made of the conductive resin composition of the present invention are electric and electronic parts, OA equipment parts, semiconductor-related members, and automobile exterior parts.

The surface resistivity of the molded article of the present invention is 10 ¹² Ω / sq or less, preferably 10 ² to 10 ¹² Ω / sq, and more preferably 10 ⁴ to 10 ¹⁰ Ω / sq. When the surface resistivity is higher than 10 ¹² Ω / sq, the electric charge is easily charged, and dust and dust are likely to adhere to the surface of the molded product, and the spark current when the charged electric charge is discharged increases. This is not preferred because there is a high possibility of damaging precision equipment around the molded product. The surface resistivity of the molded product was measured using a resistivity meter suitable for each resistance value. That is, in the case of 10 ¹⁰ Ω / sq or more, digital insulation meter DSM-8103 (applied voltage 100 V, dedicated probe) manufactured by TOA Co., Ltd., and in the case of 10 ⁷ to 10 ¹⁰ Ω / sq, manufactured by Mitsubishi Chemical Corporation High Lester UP MCP-HT400 (applied voltage 100V, UR-SS probe (JISK6911 compliant)), 10 ⁷ Ω / sq or less, Lorester GP MCP-T600 (applied voltage 90V, ESP probe (JISK7194) Compliant)). As a specific measurement method, three test pieces (length × width × thickness = 90 mm × 50 mm × 2 mmt) are cut from the molded product, and the above-described resistivity meter is used under the conditions of a temperature of 23 ° C. and a humidity of 50% RH. The surface resistivity of the central part in the test piece surface was measured and the average value of the values obtained from the three test pieces was defined as the surface resistivity of the test piece.

In addition, since the surface resistivity in the molded article of the present invention may be greatly influenced by the fluidity of the resin composition, a method of controlling the fluidity can be taken as one of the adjustment methods. Specifically, melt volume flow rate of the resin composition (MVR) is preferably 5~80cm ^3/10 min, more preferably 5 to 50 cm ^3/10 min, even more preferably 10 to 30 cm ^3/10 min When it shows, favorable surface resistivity can be obtained. The melt volume flow rate of such a resin composition is measured by a method based on ISO 1133 (JIS K 7210) at a cylinder and piston temperature of 300 ° C. and a load of 2.16 kg.

  The half decay time of the molded article of the present invention when 10 kV is applied is 10 seconds or less, preferably 5 seconds or less, and more preferably 3 seconds or less. When the charged voltage half decay time exceeds 10 seconds, a new charge is generated before the charged charge is completely attenuated. As a result, dust and dust are likely to adhere to the surface of the molded product. This is not preferable because the spark current when the electric charge is discharged becomes large and there is a high possibility of damaging precision equipment around the molded product. The half decay time of the molded product was measured by the following method. That is, the molded article made of the conductive resin composition of the present invention was measured at a applied voltage of 10 kV using a static honestometer (H-0110, manufactured by Sisid Electric Co., Ltd.). Specifically, three test pieces (length × width × thickness = 60 mm × 50 mm × 2 mmt) were cut from the molded product, and the above-mentioned static honometer was used under the conditions of a temperature of 23 ° C. and a humidity of 50% RH. Then, the half voltage decay time at the center of the test piece surface was measured, and the average value of the values obtained from the three test pieces was taken as the half voltage decay time of the test piece.

It is the schematic which shows the precision member storage container used in the Example of this invention.

  Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these.

[Examples 1 to 13, Comparative Examples 1 to 10]
1. Production of composition pellets Composition pellets were produced by the following method.
Each component shown in Table 1 and Table 2 was dry blended in the proportions shown in Table 1 and Table 2, and then the diameter of 30 mmφ, L / D = 33.2, a vented two-piece equipped with screws in two kneading zones. Using a shaft extruder (Kobe Steel Ltd .: KTX30), melt kneading was performed at a cylinder temperature of 270 ° C., extrusion, and strand cutting to obtain pellets of each composition.

2. Preparation of molded product The resin composition was molded by injection molding at a cylinder temperature of 300 ° C and a mold temperature of 80 ° C, and a test piece was cut according to various evaluations.

3. Evaluation method Each value in the examples was determined by the following method.
(1) Surface resistivity The molded product obtained by the above method was measured using a resistivity meter suitable for each resistance value. That is, in the case of 10 ¹⁰ Ω / sq or more, digital insulation meter DSM-8103 (applied voltage 100 V, dedicated probe) manufactured by TOA Co., Ltd., and in the case of 10 ⁷ to 10 ¹⁰ Ω / sq, manufactured by Mitsubishi Chemical Corporation High Lester UP MCP-HT400 (applied voltage 100V, UR-SS probe (JISK6911 compliant)), 10 ⁷ Ω / sq or less, Lorester GP MCP-T600 (applied voltage 90V, ESP probe (JISK7194) Compliant)). As a specific measurement method, three test pieces (length × width × thickness = 90 mm × 50 mm × 2 mmt) are cut from the molded product, and the above-described resistivity meter is used under the conditions of a temperature of 23 ° C. and a humidity of 50% RH. The surface resistivity of the central part in the test piece surface was measured and the average value of the values obtained from the three test pieces was defined as the surface resistivity of the molded product.

(2) Half decay time The molded product obtained by the above method was measured at a applied voltage of 10 kV using a static honestometer (H-0110 manufactured by Sisid Electric Co., Ltd.). Specifically, three test pieces (length × width × thickness = 60 mm × 50 mm × 2 mmt) were cut from the molded product, and the above-mentioned static honometer was used under the conditions of a temperature of 23 ° C. and a humidity of 50% RH. Then, the half voltage decay time at the center of the test piece surface was measured, and the average value of the values obtained from the three test pieces was taken as the half voltage decay time of the molded product.

(3) Generated gas amount 3 g of the composition pellets obtained by the above method are heated at 150 ° C. for 1 hour, the amount of volatile organic gas is measured with a gas chromatogram (GC-MS manufactured by Agilent), and the total amount is determined. The amount converted to toluene was defined as the amount of generated gas. In addition, in order to ensure the cleanliness of the molded product, the amount of generated gas needs to be 2.0 ppm or less.

(4) Separability of conductive carbon material The composition pellets obtained by the above method were used with an injection molding machine (Mitsubishi Heavy Industries, Ltd .: 80MSP-5), cylinder temperature 280 ° C, mold temperature 80 ° C. Then, a test specimen for measurement (a pin-shaped molded piece having a diameter × height = 10 mm × 20 mm) was formed, and a reciprocating friction wear tester (manufactured by Olintec Co., Ltd .: AFT-15M) was used at 23 ° C. The traces of the conductive carbon material adhering to the mount by reciprocating friction on the mount under a constant load of 0.5 kg under the condition of 50% RH were evaluated. Evaluated as ◯ when the trace of the conductive carbon material is hardly seen on the mount, △ when the trace of the conductive carbon material is observed as △, and x when the trace of the conductive carbon material can be clearly confirmed did.

(5) Fluidity The composition pellets obtained by the above method were used with an injection molding machine (Sumitomo Heavy Industries, Ltd .: SG-150U), cylinder temperature 300 ° C, mold temperature 80 ° C, injection pressure. At 119 MPa, an Archimedean spiral length with a channel thickness of 1 mm and a channel width of 8 mm was measured. The case where the spiral length was 10 cm or more was evaluated as ◯, the case where it was 5-10, and the case where it was 5 or less as x.

(6) Spark current Using a CDM tester (HED-C5000, manufactured by Hanwa Denshi Kogyo Co., Ltd.), the molded product obtained by the above method is applied in accordance with JEDEC / JESD22-C101-C. Measured by application. Specifically, a test piece (length × width × thickness = 45 mm × 45 mm × 2 mmt) was cut from the molded product, and the above-described CDM tester was used under the conditions of a temperature of 25 ° C. and a humidity of 50% RH. The average value of the values obtained by measuring the spark current at 9 locations at intervals of 5 mm was taken as the spark current of the molded product. This spark current needs to be 10 A or less.

(7) Weld strength retention rate The composition pellets obtained by the above method were used at an injection molding machine (Mitsubishi Heavy Industries, Ltd .: 80MSP-5) at a cylinder temperature of 300 ° C and a mold temperature of 80 ° C. Weld tensile strength was measured using a tensile test piece having a weld part in the center prepared according to the ASTM D638 method, and compared with the tensile strength measured using a tensile test piece having no weld part. Was calculated. It is necessary that the weld strength retention is 70% or more.
Weld strength retention rate (%) = {(tensile strength with weld) / (tensile strength without weld)} × 100

Tables 1 and 2 show the evaluation results of the examples and comparative examples.
In addition, the raw material used by the Example and the comparative example is as follows.
(Component A: aromatic polycarbonate)
A-1: Aromatic polycarbonate (L-1225 manufactured by Teijin Chemicals Ltd.)
(B component: polyethylene terephthalate)
B-1: Polyethylene terephthalate resin (TR-4550BH manufactured by Teijin Limited)
B-2: Polyethylene terephthalate resin (TRN-8550FF manufactured by Nanya Plastic Co., Ltd.)
(C component: conductive carbon material)
C-1: Conductive carbon black [Ketjen Black EC-600JD (manufactured by Lion Corporation, DBP oil absorption 495 ml / 100 g, BET specific surface area 1270 m ² / g)]
C-2: Conductive carbon black [Denka Black (DBP oil absorption 191 ml / 100 g, BET specific surface area 68 m ² / g, manufactured by Denki Kagaku Kogyo Co., Ltd.)]
C-3: Conductive carbon black [MA-600 (DBP oil absorption 131 ml / 100 g, BET specific surface area 140 m ² / g, manufactured by Mitsubishi Chemical Corporation)]
C-4: Carbon nanotube [15 wt% carbon nanotube master MB 6015-00 (Hyperion, diameter 20 nm, aspect ratio 5 or more)]
(D component: hydrogenated styrene thermoplastic elastomer)
D-1: Styrene-hydrogenated poly (isoprene / butadiene) -styrene copolymer (SEEPS) [Septon 4077 (manufactured by Kuraray Co., Ltd., styrene content 30% by weight)]
D-2: Styrene-hydrogenated polyisoprene-styrene copolymer (SEPS) [Septon 2005 (manufactured by Kuraray Co., Ltd., styrene content 20% by weight)]
D-3: Styrene-hydrogenated polyisoprene-styrene copolymer (SEPS) [Septon 2006 (Kuraray Co., Ltd., styrene content 35% by weight)]
D-4: Styrene-hydrogenated polyisoprene-styrene copolymer (SEPS) [Septon 2004 (manufactured by Kuraray Co., Ltd., styrene content 18% by weight)]
D-5: Styrene-hydrogenated polyisoprene-styrene copolymer (SEPS) [Septon 2104 (manufactured by Kuraray Co., Ltd., styrene content 65% by weight)]
D-6: Styrene-hydrogenated polybutadiene-styrene copolymer (SEBS) [Tuftec H1051 (manufactured by Asahi Kasei Chemicals Corporation, styrene content 42% by weight)]
D-7: MBS [Paraloid EXL-2678 (Rohm and Haas Japan, styrene content 40% by weight)]
(E component: polytetrafluoroethylene particles)
E-1: Lubron L-5 (manufactured by Daikin Industries, Ltd.)
(F component: stabilizer)
F-1: ADK STAB PEP-24G (Asahi Denka Kogyo Co., Ltd.)

  As shown in Examples 1 to 5, it is composed of a resin composition in which polyethylene terephthalate and hydrogenated styrene thermoplastic elastomer within a specified range amount are blended, and the conductive carbon material is unevenly distributed in the polyethylene terephthalate phase. Molded products that can obtain electrical conductivity with the added amount of carbonaceous material and have controlled surface resistivity and charged voltage half decay time suppress the spark current generated from the molded product surface and have high weld strength retention. Furthermore, it is excellent in fluidity and detachability of the conductive carbon material from the surface of the molded product.

  In Comparative Example 1 and Comparative Example 2, the blending amount of polyethylene terephthalate is outside the specified range. In Comparative Example 1, polyethylene terephthalate is not blended, and the amount of conductive carbon material added to obtain conductivity is sufficient. In addition, dropping of the conductive carbon material cannot be suppressed, and the fluidity is poor. In Comparative Example 2, the blending amount of polyethylene terephthalate is large, and the conductivity cannot be controlled within the specified range.

  In Comparative Example 3 and Comparative Example 4, the blending amount of the conductive carbon material is outside the specified range, and in Comparative Example 3, the blending amount of the conductive carbon material is small, and the conductivity cannot be obtained. In Comparative Example 4, the amount of the conductive carbon material is large, and the conductive carbon material is frequently dropped.

  In Comparative Example 5 and Comparative Example 6, the blended amount of the hydrogenated styrene-based thermoplastic elastomer is outside the specified range, and since Comparative Example 5 does not include the hydrogenated styrene-based thermoplastic elastomer, the weld strength retention is low. Sufficient mechanical properties cannot be obtained. Since Comparative Example 6 has a large amount of hydrogenated styrene-based thermoplastic elastomer and a large amount of volatile organic gas, it is difficult to develop for use in the present invention.

  Comparative Examples 7 to 9 use a hydrogenated styrene-based thermoplastic elastomer whose styrene content is outside the specified range. Since Comparative Example 7 has a low styrene content, the compatibility between polycarbonate and polyethylene terephthalate is poor. Since the phase structure is affected, the conductivity deteriorates. Since Comparative Example 8 and Comparative Example 9 have a high styrene content, a sufficient effect of improving the strength cannot be obtained. Moreover, since the comparative example 10 uses the styrene-type thermoplastic elastomer which is not hydrogenated, there is much generation amount of volatile organic gas.

  In Examples 6 to 13, when the type of hydrogenated styrene-based thermoplastic elastomer is changed, when the type of conductive carbon black is changed, when polytetrafluoroethylene particles are further added, when a stabilizer is further added, The case where the kind of polyethylene terephthalate was changed is shown, and all show a favorable evaluation result.

1 Container body 2 Recess

Claims (7)

1 to 20 parts by weight of a conductive carbon material (C component) with respect to 100 parts by weight of a resin component composed of 51 to 95% by weight (A component) of an aromatic polycarbonate resin and 5 to 49% by weight (B component) of a polyethylene terephthalate resin And a molded article comprising a conductive resin composition containing 0.1 to 10 parts by weight of a hydrogenated styrene-based thermoplastic elastomer (component D) having a styrene content of 20 to 40% by weight, The surface resistivity is 10 ¹² Ω / sq or less, and the half decay time when 10 kV is applied is 10 seconds or less. From electrical and electronic parts, OA equipment parts, semiconductor-related parts, and automobile exterior parts A molded article comprising a conductive resin composition selected from the group consisting of:   The molded article comprising the conductive resin composition according to claim 1, wherein the conductive carbon material (component C) is conductive carbon black or carbon nanotube.   The conductive carbon material (component C) is carbon black having an n-dibutyl phthalate (DBP) oil absorption of 400 ml / 100 g or more, or a carbon nanotube having a diameter of 0.7 to 100 nm and an aspect ratio of 5 or more. A molded article comprising the conductive resin composition according to claim 1 or 2.   Hydrogenated styrene-based thermoplastic elastomer (component D) having a styrene content of 20 to 40% by weight is styrene-hydrogenated polybutadiene-styrene copolymer (SEBS), styrene-hydrogenated polyisoprene-styrene copolymer (SEPS). And a styrene-hydrogenated poly (isoprene / butadiene) -styrene copolymer (SEEPS). 5. A molded article comprising the conductive resin composition according to claim 1.   The molding which consists of 1-10 weight part of (E) polytetrafluoroethylene particle | grains (E component) per 100 weight part of total of A component and B component, and consists of a conductive resin composition in any one of Claims 1-4 Goods.   A molded article comprising the conductive resin composition according to any one of claims 1 to 5, wherein (F) the stabilizer (F component) is contained in an amount of 0.001 to 2 parts by weight per 100 parts by weight in total of the A component and the B component. .   The molded article made of the conductive resin composition according to any one of claims 1 to 6, wherein the amount of volatile organic gas after standing at 150 ° C for 1 hour is 2 ppm or less.

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