JP5296622B2 - Molded product comprising conductive resin composition - Google Patents

Abstract

The invention provides a molding made from a conductive resin composition. The surface of the molding can be prevented from being adhered to dust or dust or dirt and the spark current can be prohibited by controlling the surface resistivity and static voltage half life within a conductive area. As the conductive carbon material is not easy to fall off, the flowability and appearance are good. The invention is characterized in that the molding is formed by a conductive resin composition comprising 1-20 parts by weight of conductive carbon material (C component) relative to 100 weight parts of resin; the resin comprises 75-95% by weight aromatic polycarbonate resin (A component) and 5-25% by weight polyethylene terephthalate (B component). The invention is the molding for electric and electronic components, office equipment components, semiconductor related components, glass containers and automobile external mounted components which meets the requirement of (1) and (2) and comprises parts like a photography shutter. The surface resistivity of (1) is 100-105 Omega/sq, and the half life of (2) applied with 10kv is lower than 10 seconds.

Description

  The present invention relates to a molded article made of a conductive resin composition. More specifically, the present invention can be controlled to have good conductivity and rapid voltage decay, prevent dust and dust from adhering to the surface of the molded product, and the spark current generated from the surface of the molded product is small. Electrical and electronic parts including camera shutter parts, OA equipment parts, semiconductor-related parts, glass containers, or automobile exteriors that have a low dropout of the conductive carbon material from the resin surface of the molded product and that are excellent in fluidity and appearance. The present invention relates to a molded article made of a conductive resin composition suitable for parts.

  Electrical and electronic parts such as camera shutter parts such as shutter base plates, shutter blade retainers, and intermediate boards incorporated in cameras, OA equipment parts, and semiconductor-related parts will malfunction if charged even a little due to friction during their operation. There is a risk, antistatic performance is required. For this purpose, it is necessary to reduce the surface resistivity and speed up the charge decay time so that charges can easily escape. Also, good conductivity is extremely effective in preventing the adhesion of surrounding dust and dust.

  In addition, as products become smaller and lighter, with higher integration and higher precision, the reduction of dust and dust adhesion in related processes has become more and more severe year by year, and it has an antistatic function to prevent further adhesion. In addition, there is an increasing demand for dust generated from parts, that is, what is called conductive carbon material falling off.

  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. 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. 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 has been proposed that the dispersion of conductive carbon black is unevenly distributed in the polyethylene terephthalate phase. 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.

Japanese Patent No. 3897512 JP 2005-120323 A

  The object of the present invention is to control the surface resistivity and charged voltage half decay time of the molded product in the conductive region, thereby preventing dust and dust from adhering to the molded product surface and generating from the molded product surface. Electrical and electronic parts including camera shutter parts, OA equipment parts, and semiconductors that suppress spark current and, in addition, have less conductive carbon material falling off from the resin surface of the molded product, and also have excellent fluidity and appearance. An object of the present invention is to provide a molded article made of a conductive resin composition suitable for a related member, a glass container or an automobile exterior part.

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 75 to 95% by weight of aromatic polycarbonate resin (A component) and 5 to 25% by weight of polyethylene terephthalate resin (B component). In addition to controlling the surface resistivity of the molded article made of the conductive resin composition to 10 ⁰ to 10 ⁵ Ω / sq, which is a conductive region, by adding 1 to 20 parts by weight of component) 10 kV The inventors have found a surprising effect that by controlling the half decay time when applied to 10 seconds or less, it is also possible to reduce the spark current that is one of the electrostatic disturbances. Furthermore, when the addition amount of polyethylene terephthalate is limited to a limited range of 5 to 25% by weight, the effect of reducing the spark current can be exhibited with a smaller addition amount of the conductive carbon material, in addition to molding. It has been found that dust and dust can be prevented from adhering to the resin surface of the product and that the conductive carbon material can be prevented from dropping off, and the present invention has been completed.

  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 reason why the molded article can exhibit the effect of reducing the spark current with a smaller amount of the conductive carbon material added is presumably because the conductive carbon material is unevenly distributed only in polyethylene terephthalate. The reason why the conductive carbon material can be prevented from falling off from the resin surface of the molded product by blending polyethylene terephthalate is considered to be because the familiarity between the surface of the conductive carbon material and polyethylene terephthalate is good.

  The molded article made of the resin composition of the present invention prevents dust and dust from adhering to the molded article surface, has a small spark current that becomes one of the static electricity obstacles, has little drop off of the conductive carbon material, and has a suitable flow. Therefore, it is useful for electrical and electronic parts including camera shutter parts, OA equipment parts, semiconductor-related member glass containers, and automobile exterior parts.

It is the schematic which shows the camera shutter components used in the Example of this invention.

<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 such polyethylene terephthalate (component B) is 5 to 25% by weight, preferably 10 to 25% by weight, more preferably 13 to 25% by weight per 100% by weight in total with the aromatic polycarbonate (component A). Preferably, 15 to 25% 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 25% by weight, the conductive carbon material of the polyethylene terephthalate phase is diluted, the surface resistivity becomes higher than 10 ⁵ 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.

  The content of the conductive carbon material (component B) is 1 to 20 parts by weight, preferably 2 to 15 parts by weight, and more preferably 3 to 10 parts by weight based on 100 parts by weight of the resin component. 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: Glass fiber and / or glass flake>
The glass fiber and / or glass flake used in the present invention is blended for improving the strength and reducing the warpage of the molded product.

(Glass fiber)
The glass fiber that can be used in the present invention can be selected from, for example, a long fiber type (roving), a short fiber chopped strand, a milled fiber, and the like. In the milled fiber, the number average aspect ratio is preferably 5 or more.

  Glass fibers include sizing agents (for example, polyvinyl acetate, urethane, acrylic, epoxy, polyester sizing agents, etc.), coupling agents (for example, silane compounds, boron compounds, titanium compounds, etc. including alkylalkoxysilanes, polyorganohydrogensiloxanes, etc.) ) Or other surface treatment agents. Examples of such other surface treatment agents include higher fatty acid esters, acid compounds (for example, phosphorous acid, phosphoric acid, carboxylic acid, and carboxylic acid anhydride), and waxes. Furthermore, it may be granulated with a sizing agent such as various resins, higher fatty acid esters, and waxes.

(Glass flakes)
The glass flakes used in the present invention have a scaly or layered shape having a diameter of at least several times the thickness, and the flow direction (MD) of the molded product made of the conductive resin composition. It is blended to alleviate and reduce the difference in molding shrinkage in the vertical direction (TD), reduce warpage, and stabilize the dimensions, but also contributes to the improvement of rigidity. Glass flakes are generally expressed by their average thickness and particle size distribution, and are not particularly limited to these conditions, but for the particle size, the median diameter by the standard sieving method is preferably 100 to 500 μm, more preferably. May be in the range of 100 to 400 μm, more preferably 120 to 300 μm, and particularly preferably 120 to 200 μm.

  The glass flakes used in the present invention can be obtained by a conventionally known production method. For example, a glass raw material is melted in a melting furnace, the melt is drawn into a tube shape, the glass film thickness is made constant, and then crushed with a roll to obtain a frit having a specific film thickness. It can be ground into flakes having the desired aspect ratio.

  Here, if the value obtained by dividing the particle size of the glass flake by the thickness of the glass flake is defined as the aspect ratio of the glass flake, the value of this aspect ratio is preferably 9 or more (when the thickness is 5 μm, the particle size is 45 μm or more). The total particle size distribution is 75% or more, more preferably the aspect ratio value is 28 or more (when the thickness is 5 μm, the particle size is 140 μm or more). It can be suitably used for reducing or reducing the difference in shrinkage between the flow direction (MD) and the vertical direction (TD) of a molded article made of a conductive resin composition.

  Such glass fiber and / or glass flake (component D) is preferably blended in an amount of 5 to 50 parts by weight, more preferably 10 to 40 parts by weight, per 100 parts by weight of the total of component A and component B. When glass fibers and / or glass flakes are blended, the aim is to improve strength and reduce warpage of the molded product. However, if the amount is less than 5 parts by weight, the desired performance cannot be obtained. It deteriorates and is not preferable in terms of productivity. Of course, it goes without saying that glass fibers and glass flakes are used in combination according to the desired properties, and the blending ratio is determined according to the desired properties.

<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: Antioxidant>
The antioxidant (component F) is at least one selected from the group consisting of phosphite compounds, phosphonite compounds, hindered phenol compounds, and thioether compounds. The antioxidant (F component) is particularly preferably composed of two types of phosphite compounds and hindered phenol compounds in terms of improving thermal stability.

(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 is preferable because it 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 such an antioxidant (component F) is preferably 0.001 to 2 parts by weight, more preferably 0.005 to 1 part by weight, and still more preferably 0 per 100 parts by weight of the total of component A and component B. 0.01 to 0.5 parts by weight. When the blending amount is less than 0.001 part by weight, the anti-oxidation effect is insufficient, so the residence heat stability is lowered. When it exceeds 2 parts by weight, not only the antioxidant effect is lowered, but also the antioxidant-derived effect is derived. The amount of gas generated due to volatile matter increases, and the cleanliness of the molded product may be impaired.

  Moreover, it is preferable to use the phosphorus stabilizer and the hindered phenol stabilizer in combination. By using a combination of a phosphorus-based stabilizer and a hindered phenol-based stabilizer, a synergistic effect as a stabilizer is exhibited, and deterioration of thermal stability during molding can be further suppressed.

<Other additives>
In the composition of the present invention, other thermoplastic resins (for example, polyarylate resin, liquid crystalline polyester resin, polyamide resin, polyimide resin, polyetherimide 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 excluding D component (carbon fiber, carbon flake, etc.), Machine fillers (aramid fibers, kenaf fibers, etc.), impact modifiers (core shell acrylic rubber, core shell butadiene rubber, etc.), UV absorbers (benzotriazole, triazine, benzophenone, etc.), light stabilizers (HALS) ), Mold release agents (saturated fatty acid esters, unsaturated fatty acid esters, paraffin wax, beeswax, etc.), flow modifiers (polycaprolactone, etc.), colorants (carbon black, titanium diacid, 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.), infrared absorbers, photochromic agents and ultraviolet absorbers. 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 A component and the additive such as the D component and the D component to prepare a master batch of the additive diluted with the powder. It is done. 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 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, the cleanliness deteriorates and 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 include electrical and electronic parts including camera shutter parts, OA equipment parts, semiconductor-related members, glass containers, and automobile exterior parts.

The surface resistivity of the molded article of the present invention is 10 ⁰ to 10 ⁵ Ω / sq, preferably 10 ⁰ to 10 ⁴ Ω / sq, and more preferably 10 ¹ to 10 ³ Ω / sq. When the surface resistivity is higher than 10 ⁵ Ω / sq, it is not preferable because electric charges are easily charged and dust or dust tends to adhere to the surface of the molded product. Also, a high surface resistivity is not preferable because the spark current increases. 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 1~80cm ^3/10 min, more preferably 2~50cm ^3/10 min, even more preferably 3~20cm ^3/10 min When it shows, favorable surface resistivity can be obtained. The melt volume flow rate of such a resin composition is measured at a cylinder and piston temperature of 300 ° C. and a load of 1.2 kg by a method in accordance with ISO 1133 (JIS K 7210).

  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. If 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, resulting in a spark. The current value becomes large, which is not preferable. 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.

  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 10, Comparative Examples 1 to 5]
1. Production of composition pellets Composition pellets were produced by the following method.
After the components shown in Table 1 were dry blended at the ratios shown in Table 1, a twin screw extruder with a vent (Kobe Steel) equipped with 30 mmφ diameter, L / D = 33.2, and two kneading zone screws. (Commercially available from KTX30) was melt kneaded at a cylinder temperature of 290 ° C., extruded, and strand-cut to obtain pellets of each composition.

2. Production of Molded Article A camera shutter component shown in FIG. 1 was molded by injection molding of the resin composition at a cylinder temperature of 290 ° C. and a mold temperature of 80 ° C., and test pieces were 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, a test piece (length × width × thickness = 45 mm × 50 mm × 2 mmt) is cut from a 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. Then, the surface resistivity of the central portion 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, a test piece (length × width × thickness = 45 mm × 50 mm × 2 mmt) was 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. The half voltage decay time at the center of the test piece surface was measured, and the average value 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.

(4) Spark current Using the 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.

(5) Ash adhesion test The molded product obtained by the above method was placed in a plastic bag containing cigarette ash under the conditions of a temperature of 23 ° C. and a humidity of 50% RH, and exposed to the ash by shaking sufficiently. It was taken out later. Next, the molded product was tapped, and the state of the ash adhering at that time was visually evaluated. The case where ash adhesion was not observed was evaluated as ◯, the case where slight ash adhesion was observed as Δ, and the case where ash adhesion was observed as x.

(6) Separability of conductive carbon material Using composition molding pellets obtained by the above method using 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.

(7) Fluidity Using the injection molding machine (Sumitomo Heavy Industries, Ltd. product: SG-150U), the cylinder temperature is 300 ° C., the mold temperature is 80 ° C., and the injection pressure is used for the composition pellets obtained by the above method. 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.

(8) Appearance Using the injection molding machine (Toshiba Machine Co., Ltd. product: IS-150EN), the composition pellet obtained by the above method was measured at a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C. A test piece (formed piece of length × width × thickness = 90 mm × 50 mm × 2 mmt) was formed, and the surface appearance of the formed piece was visually evaluated. A case where the surface was smooth was evaluated as ◯, a case where a slight roughness was observed, and a case where the roughness was observed were evaluated as ×.

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)
(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: glass fiber, glass flake)
D-1: Glass fiber [CS 3PE-937 (manufactured by Nitto Boseki Co., Ltd.)]
D-2: Glass flake [REFG-301 (made by Nippon Sheet Glass Co., Ltd.)]
(E component: polytetrafluoroethylene particles)
E-1: Lubron L-5 (manufactured by Daikin Industries, Ltd.)
(F component: antioxidant)
F-1: ADK STAB PEP-24G (Asahi Denka Kogyo Co., Ltd.)
F-2: TMP (manufactured by Daihachi Chemical Industry Co., Ltd.)

As shown in Example 1, Example 2 and Example 5, it consists of a resin composition blended with polyethylene terephthalate within a specified range amount, and has a surface resistivity of 10 ⁰ to 10 ⁵ Ω / sq which is a semiconductive region and Molded products with a charged voltage half decay time controlled to 10 seconds or less prevent dust and dust from adhering to the molded product surface, suppresses the spark current generated from the molded product surface, and conducts from the resin surface of the molded product. The carbon material is prevented from falling off, and is excellent in fluidity and appearance. Incidentally, melt volume flow rate of the resin composition of Example 1 is ^{3 cm} 3/10 min, the resin composition of Example 2 is ^{4 cm} 3/10 min, the resin composition of Example 5 is ^{4 cm} 3/10 min The fluidity suitable for controlling the surface resistivity in the electrostatic region is exhibited. On the other hand, melt volume flow rate of the resin composition in Comparative Example 1 is 1 cm ^3/10 min, it is difficult to control the surface resistivity of the electrostatic area.

  In Comparative Example 1, Comparative Example 2 and Comparative Example 3, the blending amount of polyethylene terephthalate is outside the specified range, and in Comparative Example 1, polyethylene terephthalate is not blended. Therefore, sufficient conductivity is obtained when the blending amount of the conductive carbon material is small. The ash is not easily obtained. If the blending amount of polyethylene terephthalate is small as in Comparative Example 2, the dropping of the conductive carbon material cannot be sufficiently suppressed. On the other hand, when the blending amount is large as in Comparative Example 3, the surface resistivity cannot be controlled within the specified range, and ash tends to adhere.

  In Comparative Example 4 and Comparative Example 5, the blending amount of the conductive carbon material is outside the specified range, and when the blending amount is small as in Comparative Example 4, it is difficult to control the surface resistivity within the specified range. Ashes are likely to adhere and the spark current is large. On the other hand, when there are many compounding quantities like the comparative example 5, drop-off | omission of an electroconductive carbon material cannot fully be suppressed, but fluidity | liquidity is also bad.

  In Example 3, Example 4 and Examples 6 to 10, when the kind of conductive carbon black is changed, when glass fiber or glass flake is further blended, when polytetrafluoroethylene particles are further blended, the antioxidant Is shown, and all show good evaluation results.

1: Hole (φ30mm)
2: Hole (φ10mm)
3: Semicircular hole (φ20mm)
4: Recess

Claims (5)

N-dibutyl phthalate (DBP) oil absorption is 495 ml / 100 g or more with respect to 100 parts by weight of a resin component comprising 75 to 95% by weight of aromatic polycarbonate resin (component A) and 5 to 25% by weight of polyethylene terephthalate resin (component B). A molded article comprising a conductive resin composition containing 1 to 20 parts by weight of carbon black (component C), wherein the molded article satisfies the following (1) and (2) and includes an electric part including a camera shutter A molded article made of a conductive resin composition, which is a molded article selected from the group consisting of electronic parts, OA equipment parts, semiconductor-related members, glass containers, and automobile exterior parts.
(1) The surface resistivity is 10 ⁰ to 10 ⁵ Ω / sq.
(2) The half decay time when 10 kV is applied is 10 seconds or less. Glass fibers and / or glass flakes (D component) a molded article comprising the conductive resin composition of claim 1 containing a total of 5 to 50 parts by weight per 100 parts by weight of A component and B component. The molded article which consists of a conductive resin composition of Claim 1 or 2 which contains 1-10 weight part of polytetrafluoroethylene particles (E component) per 100 weight part in total of A component and B component. A molded article comprising the conductive resin composition according to any one of claims 1 to 3 , wherein the antioxidant (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 comprising the conductive resin composition according to any one of claims 1 to 4 , wherein the amount of volatile organic gas after standing at 150 ° C for 1 hour is 2 ppm or less.

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