JP2012077242A - Electroconductive thermoplastic resin composition and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electroconductive thermoplastic resin composition suppressing the retention-caused thermal deterioration of a polycarbonate resin/polyethylene terephthalate resin/carbon black composite resin composition and improved in molding stability, electroconductivity and stability thereof, and surface appearance, and to provide resin molded products provided by injection molding of the composition.SOLUTION: The electroconductive thermoplastic resin composition is provided by compounding 0.5-10 pts.mass carbon black (C) to 100 pts.mass resin component comprising 95-51 mass% polycarbonate resin (A) and 5-49 mass% polyethylene terephthalate resin (B), wherein the polyethylene terephthalate resin (B) is a polyethylene terephthalate resin treated with the deactivation treatment of the polycondensation catalyst. Resin molded products produced by injection molding of the resin composition are provided.

Description

  The present invention relates to a conductive thermoplastic resin composition. Specifically, it is a resin composition comprising a polycarbonate resin as a main resin component, a polyethylene terephthalate resin for the purpose of imparting chemical resistance and fluidity, and carbon black as a conductive filler for imparting conductivity. The present invention relates to a conductive thermoplastic resin composition having excellent thermal stability and excellent fluidity, molding stability, conductivity and stability, and a resin molded product formed by injection molding the same.

  Polycarbonate resins, especially aromatic polycarbonate resins, are excellent in impact resistance, heat distortion resistance, rigidity, dimensional stability, etc., and are therefore used in a wide range of applications such as electrical equipment, communication equipment, precision machinery, and automotive parts.

  However, since the polycarbonate resin has a problem that the chemical resistance and fluidity are low compared to other thermoplastic resin compositions, conventionally, in order to improve the chemical resistance and fluidity of the polycarbonate resin, for example, Various polycarbonate-polyester composite resin compositions in which a polyethylene terephthalate resin or the like is combined have been studied.

  Furthermore, when the polycarbonate-polyester composite resin composition is required to have antistatic properties, electromagnetic wave shielding properties, and electrostatic coating properties, the addition of various conductive fillers has been studied as a method for imparting conductivity. (For example, refer to Patent Documents 1 to 3).

JP 2006-206703 A JP 2005-120323 A JP 2006-206780 A

  When a polyethylene terephthalate resin and a conductive filler are combined with a polycarbonate resin, chemical resistance and fluidity are improved, and conductivity is imparted, while the obtained polycarbonate-polyester composite resin composition has thermal stability. There was a problem of a decrease.

  When injection molding such a resin composition having low thermal stability, the polycarbonate-polyester composite resin composition is kept at a high temperature for a long time in a resin cylinder for injection molding, whereby polycarbonate resin and polyethylene terephthalate are used. There was a problem that a transesterification reaction occurred with the resin, and the appearance of a resin molded product called foam or silver was poor due to the generation of decomposition gas due to this reaction.

  Furthermore, if the transesterification reaction between the polycarbonate resin and the polyethylene terephthalate resin proceeds due to retention at a high temperature in the resin cylinder for injection molding, the resin morphology changes, so the dispersion state of the conductive filler also changes. There is also a problem that the conductivity of the molded product is lowered.

  In addition, the polycarbonate resin decomposes and the molecular weight decreases due to the high temperature holding in the cylinder, and the impact resistance, heat distortion resistance, etc. of the polycarbonate resin are impaired due to the decrease in the molecular weight. There also exists a problem that the molding stability at the time of injection molding is impaired by the viscosity fall of the resin composition.

  In addition, it is possible to stably provide high conductivity by increasing the amount of conductive filler added, but generally conductive fillers are often expensive and the increase in the amount added is the cost of the product. In addition to increasing the amount of the conductive filler, a large amount of the conductive filler may cause deterioration in fluidity (moldability) during molding. For this reason, it is required that the conductive filler efficiently obtain desired conductivity with a minimum addition amount.

  By the way, carbon black generally used as a conductive filler is a composite resin composition of a polycarbonate resin and a polyethylene terephthalate resin, and has a structure for selectively dispersing on the polyethylene terephthalate resin side to express conductivity. Form. Therefore, when the morphology of polycarbonate resin and polyethylene terephthalate resin, which are normally dispersed in the sea-island structure, changes due to these transesterification reactions, the dispersion state of carbon black for developing conductivity also changes, and the conductivity is stable. There is also a problem that the molded product cannot be obtained.

  The present invention solves the above-mentioned conventional problems, suppresses the residence heat deterioration in the polycarbonate resin / polyethylene terephthalate resin / carbon black composite resin composition, and also provides molding stability, conductivity and stability thereof, and further the surface of the molded product. It is an object of the present invention to provide a conductive thermoplastic resin composition having an improved appearance and a resin molded product obtained by injection molding the same.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the above-mentioned problem of residence heat deterioration in the polycarbonate resin / polyethylene terephthalate resin / carbon black composite resin composition is used in the production process of polyethylene terephthalate resin, This is due to the polycondensation catalyst contained in the polyethylene terephthalate resin provided as a product. Therefore, as the polyethylene terephthalate resin, by using the polyethylene terephthalate resin in which this polycondensation catalyst is deactivated, the residence heat deterioration It has been found that can be suppressed.
Furthermore, since the transesterification reaction between the polycarbonate resin and the polyethylene terephthalate resin is suppressed by the polyethylene terephthalate resin in which the polycondensation catalyst is deactivated, the morphology of the composite resin composition is stabilized, and as a result, a conductive filler is obtained. The dispersion state of carbon black is also stable, so there is little variation in the conductive performance of the molded product by injection molding, etc., and not only a product with stable quality can be obtained, but also the surface appearance of the molded product will be good, and polyethylene Since the decrease in crystallinity of the terephthalate resin is suppressed, the crystallization shrinkage of the polyethylene terephthalate resin is effectively performed during injection molding, and it has been found that the releasability from the mold is maintained relatively well. It was.

  The present invention has been achieved based on such findings, and the gist thereof is as follows.

[1] Carbon black (C) 0.5 to 10 parts by mass is blended with 100 parts by mass of a resin component composed of 95 to 51% by mass of the polycarbonate resin (A) and 5 to 49% by mass of the polyethylene terephthalate resin (B). A conductive thermoplastic resin composition, wherein the polyethylene terephthalate resin (B) is a polyethylene terephthalate resin that has been subjected to a deactivation treatment of a polycondensation catalyst.

[2] Polyethylene terephthalate resin subjected to the deactivation treatment of the polycondensation catalyst has a terminal carboxyl group concentration of 5 to 40 μeq / g, an intrinsic viscosity [η] of 0.6 to 1.5 dl / g, and is based on all constituent repeating units. The ratio of the oxyethyleneoxyterephthaloyl unit is 90 equivalent% or more, and the solid phase polymerization rate Ks calculated by the following formula (1) is 0.006 (dl / g · hr) or less. [1] The conductive thermoplastic resin composition according to [1].
Solid-phase polymerization rate Ks = ([η] s− [η] m) / T (1)
(Where [η] s is the intrinsic viscosity (dl / g) of the polyethylene terephthalate resin after holding the polyethylene terephthalate resin at 210 ° C. for 3 hours under a nitrogen stream, and [η] m is a nitrogen stream. (Inherent viscosity (dl / g) of the polyethylene terephthalate resin after being kept at 210 ° C. for 2 hours, T is 1 (hour).)

[3] The specific surface area of the carbon black (C) (BET equation nitrogen adsorption method) 30~1500m ² / g, and a dibutyl phthalate (DBP) absorption is characterized by a 100~500cm ³ / 100g [1 ] Or the conductive thermoplastic resin composition according to [2].

[4] Furthermore, with respect to a total of 100 parts by mass of the polycarbonate resin (A) and the polyethylene terephthalate resin (B), 0.01 to 0.5 parts by mass of a phosphorus-based thermal stabilizer as a thermal stabilizer (D) and / or Alternatively, the conductive thermoplastic resin composition according to any one of [1] to [3], further comprising 0.01 to 1 part by mass of a hindered phenol heat stabilizer.

[5] Furthermore, 1 to 15 parts by mass of the rubbery polymer (E) is contained with respect to 100 parts by mass in total of the polycarbonate resin (A) and the polyethylene terephthalate resin (B). The conductive thermoplastic resin composition according to any one of [4].

[6] The conductive thermoplastic resin composition according to any one of [1] to [5], wherein the volume resistivity change calculated by the following formula (2) is 3 or less.
Volume resistivity change = [R _x ] / [R _o ] (2)
(However, in the above formula (2), [R _x ] is the volume resistivity of a molded product that is injection-molded after the resin composition is retained in an injection molding machine at 280 ° C. for 20 minutes, and [R ₀ ] is (The volume resistivity of each of the molded products obtained by injection molding immediately after the resin composition is injected into the injection molding machine is shown.)

[7] A resin molded product obtained by injection molding the conductive thermoplastic resin composition according to any one of [1] to [6].

  According to the present invention, a polycarbonate resin excellent in impact resistance, heat distortion resistance, rigidity, dimensional stability, etc. is combined with a polyethylene terephthalate resin for improving chemical resistance and fluidity, and imparted with conductivity. In addition to improving the thermal stability of the polycarbonate resin / polyethylene terephthalate resin / carbon black composite resin composition containing carbon black for the purpose, the conductive performance and its stability, as well as the mold release and moldability during injection molding, The appearance of the surface of the molded product is improved, and a product with high quality and excellent quality stability is provided.

  The conductive thermoplastic resin composition of the present invention having such excellent features is used in various applications such as electrical / electronic equipment parts, OA equipment, machine parts, vehicle parts, building members, various containers, leisure goods and miscellaneous goods. Useful for.

Suitable applications of the conductive thermoplastic resin composition of the present invention include bumpers, fenders, door panels, trunk lids, front panels, rear panels, roof panels, bonnets, pillars, side moldings, garnishes, wheel caps, door handles, food bulges. And automobile exterior parts used for electrostatic coating such as fuel lids and various spoilers.
Moreover, the conductive thermoplastic resin composition of the present invention can be suitably used for applications requiring electrical conductivity such as, for example, electrical / electronic / OA equipment, in addition to automotive exterior parts. For example, IC chips used in semiconductors, IC trays, wafers, internal parts of hard disks used in computers, etc. are given antistatic properties to prevent dust and dust from sticking, and malfunctions due to static electricity are prevented. It can be used for purposes such as It can also be used in applications requiring conductivity for imparting electromagnetic wave shielding properties, such as notebook computer housings, PDA housings, pachinko component substrates, camera shutters, mobile phone housings, and the like.

  Embodiments of the conductive thermoplastic resin composition of the present invention (hereinafter sometimes referred to as “the resin composition of the present invention”) and molded articles thereof will be described in detail below. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

[Polycarbonate resin (A)]
Examples of the polycarbonate resin (A) used in the resin composition of the present invention include aromatic polycarbonate resins, aliphatic polycarbonate resins, and aromatic-aliphatic polycarbonate resins, with aromatic polycarbonate resins being preferred.

  The aromatic polycarbonate resin is an optionally branched aromatic polycarbonate polymer obtained by reacting an aromatic hydroxy compound with a phosgene or carbonic acid diester. The method for producing the aromatic polycarbonate resin is not particularly limited, and may be a conventional method such as a phosgene method (interfacial polymerization method) or a melting method (transesterification method). Further, it may be a polycarbonate resin produced by a melting method and produced by adjusting the amount of OH groups of terminal groups.

Typical examples of the aromatic dihydroxy compound that is one of the raw materials of the aromatic polycarbonate resin used in the present invention include, for example, bis (4-hydroxyphenyl) methane and 2,2-bis (4-hydroxyphenyl). Propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (4-hydroxyphenyl) Cyclohexane, 4,4′-dihydroxybiphenyl, 3,3 ′, 5,5′-tetramethyl-4,4′-dihydroxybiphenyl, bis (4- Hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone and the like.
Furthermore, polyvalent phenols having three or more hydroxy groups in the molecule such as 1,1,1-tris (4-hydroxylphenyl) ethane (THPE), 1,3,5-tris (4-hydroxyphenyl) benzene Etc. can be used together in small amounts as a branching agent.
Among these aromatic dihydroxy compounds, 2,2-bis (4-hydroxyphenyl) propane (hereinafter also referred to as “bisphenol A” and sometimes abbreviated as “BPA”) is preferable. These aromatic dihydroxy compounds can be used alone or in admixture of two or more.

  In order to obtain a branched aromatic polycarbonate resin, phloroglucin, 4,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) heptene-2, 4,6-dimethyl-2,4,6-tris ( 4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) heptene-3, 1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1 -Polyhydroxy compounds such as tris (4-hydroxyphenyl) ethane, or 3,3-bis (4-hydroxyaryl) oxindole (= isatin bisphenol), 5-chloruisatin, 5,7-dichloroisatin, 5-bromoisatin, etc. May be used as a part of the aromatic dihydroxy compound, and the amount used thereof may be And from 0.01 to 10 mol% against, and preferably 0.1 to 2 mol%.

  In the polymerization by the transesterification method, a carbonic acid diester is used as a monomer instead of phosgene. Representative examples of the carbonic acid diester include substituted diaryl carbonates typified by diphenyl carbonate and ditolyl carbonate, and dialkyl carbonates typified by dimethyl carbonate, diethyl carbonate, di-tert-butyl carbonate and the like. These carbonic acid diesters can be used alone or in admixture of two or more. Among these, diphenyl carbonate (hereinafter sometimes abbreviated as “DPC”) and substituted diphenyl carbonate are preferable.

  Moreover, said carbonic acid diester may substitute the quantity of the 50 mol% or less preferably 30 mol% or less with the dicarboxylic acid or dicarboxylic acid ester preferably. Representative dicarboxylic acids or dicarboxylic acid esters include terephthalic acid, isophthalic acid, diphenyl terephthalate, and diphenyl isophthalate. When substituted with such a dicarboxylic acid or dicarboxylic acid ester, a polyester carbonate is obtained.

  When an aromatic polycarbonate is produced by a transesterification method, a catalyst is usually used. Although there is no limitation on the catalyst species, generally basic compounds such as alkali metal compounds, alkaline earth metal compounds, basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds are used. Of these, alkali metal compounds and / or alkaline earth metal compounds are particularly preferred. These may be used alone or in combination of two or more. In the transesterification method, the polymerization catalyst is generally deactivated with p-toluenesulfonic acid ester or the like.

  Preferred aromatic polycarbonate resins are polycarbonate resins derived from 2,2-bis (4-hydroxyphenyl) propane or derived from 2,2-bis (4-hydroxyphenyl) propane and other aromatic dihydroxy compounds. And polycarbonate copolymers. Further, for the purpose of imparting flame retardancy and the like, a polymer or oligomer having a siloxane structure can be copolymerized. The aromatic polycarbonate resin may be a mixture of two or more polymers and / or copolymers of different raw materials, and may have a branched structure up to 0.5 mol%.

  The terminal hydroxyl group content of the polycarbonate resin has a great influence on the thermal stability, hydrolysis stability, color tone and the like of the molded product. In order to give practical physical properties, it is usually 30 to 2000 ppm, preferably 100 to 1500 ppm, more preferably 200 to 1000 ppm, and p-tert-butylphenol is used as a sealing end agent for adjusting the terminal hydroxyl group content. , Phenol, cumylphenol, p-long chain alkyl-substituted phenol, and the like can be used.

  As the amount of residual monomer in the polycarbonate resin, the aromatic dihydroxy compound is 150 ppm or less, preferably 100 ppm or less, and more preferably 50 ppm or less. When synthesized by the transesterification method, the residual amount of carbonic acid diester is 300 ppm or less, preferably 200 ppm or less, more preferably 150 ppm or less.

  The molecular weight of the polycarbonate resin is not particularly limited, but is a viscosity average molecular weight converted from the solution viscosity measured at a temperature of 20 ° C. using methylene chloride as a solvent, and preferably in the range of 10,000 to 50,000. More preferably, it is a thing of 11,000-40,000, Most preferably, it is a thing of the range of 12,000-30,000. By setting the viscosity average molecular weight to 10,000 or more, the mechanical properties are more effectively exhibited, and by setting the viscosity average molecular weight to 50,000 or less, the molding process becomes easier. Further, two or more kinds of polycarbonate resins having different viscosity average molecular weights may be mixed, or a polycarbonate resin having a viscosity average molecular weight outside the above preferred range may be mixed to be within the above molecular weight range.

[Polyethylene terephthalate resin (B)]
The polyethylene terephthalate resin (B) used in the present invention is a ratio of oxyethyleneoxyterephthaloyl units (hereinafter sometimes referred to as “ET units”) composed of terephthalic acid and ethylene glycol to all the structural repeating units (hereinafter sometimes referred to as “ET units”). The polyethylene terephthalate resin is preferably 90 equivalent% or more, and the polyethylene terephthalate resin in the present invention contains constituent repeating units other than ET units in a range of less than 10 equivalent%. May be. The polyethylene terephthalate resin in the present invention is produced using terephthalic acid or a lower alkyl ester thereof and ethylene glycol as main raw materials, but other acid components and / or other glycol components may be used together as raw materials.

  Acid components other than terephthalic acid include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,3- Examples thereof include phenylenedioxydiacetic acid and structural isomers thereof, dicarboxylic acids such as malonic acid, succinic acid and adipic acid and derivatives thereof, and oxyacids such as p-hydroxybenzoic acid and glycolic acid or derivatives thereof.

  Examples of diol components other than ethylene glycol include 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, aliphatic glycols such as pentamethylene glycol, hexamethylene glycol, and neopentyl glycol, cyclohexane Examples include alicyclic glycols such as dimethanol, and aromatic dihydroxy compound derivatives such as bisphenol A and bisphenol S.

  The raw material containing terephthalic acid or an ester-forming derivative thereof and ethylene glycol as described above is subjected to esterification or transesterification in the presence of an esterification catalyst or transesterification catalyst, and bis (β-hydroxyethyl) terephthalate and Then, an oligomer thereof is formed, and then a melt polycondensation is performed under high temperature and reduced pressure in the presence of a polycondensation catalyst and a stabilizer to obtain a polymer.

  The esterification catalyst is not particularly required because terephthalic acid serves as an autocatalyst for the esterification reaction. The esterification reaction can be carried out in the presence of an esterification catalyst and a polycondensation catalyst described later, and can be carried out in the presence of a small amount of an inorganic acid or the like. As the transesterification catalyst, alkali metal salts such as sodium and lithium, alkaline earth metal salts such as magnesium and calcium, and metal compounds such as zinc and manganese are preferably used. Above all, on the appearance of the obtained polyethylene terephthalate resin, Manganese compounds are particularly preferred.

  As the polycondensation catalyst, compounds soluble in a reaction system such as a germanium compound, an antimony compound, a titanium compound, a cobalt compound, and a tin compound are used alone or in combination. As the polycondensation catalyst, germanium dioxide is particularly preferable from the viewpoints of color tone and transparency. These polycondensation catalysts may be used in combination with a stabilizer in order to suppress the decomposition reaction during polymerization. Examples of the stabilizer include phosphate esters such as trimethyl phosphate, triethyl phosphate and triphenyl phosphate, and triphenyl phosphate. Phosphites such as phyto, trisdodecyl phosphite, methyl acid phosphate, dibutyl phosphate, monobutyl phosphate acidic phosphate, phosphorous compounds such as phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid Or 2 or more types are preferable.

  The use ratio of the above catalyst is usually in the range of 1 to 2000 ppm, preferably 3 to 500 ppm as the weight of the metal in the catalyst in the total polymerization raw material, and the use ratio of the stabilizer is the stabilizer in the total polymerization raw material. The weight of the phosphorus atom is usually 10 to 1000 ppm, preferably 20 to 200 ppm. The catalyst and the stabilizer can be supplied at any stage of the esterification reaction or transesterification reaction in addition to the preparation of the raw slurry. Further, it can be supplied at the beginning of the polycondensation reaction step.

The reaction temperature during the esterification reaction or transesterification reaction is usually 240 to 280 ° C., and the reaction pressure is usually 0.2 to 3 kg / cm ² G (20 to 300 kPa) as a relative pressure to the atmosphere. The reaction temperature during polycondensation is usually 250 to 300 ° C., and the reaction pressure is usually 500 to 0.1 mmHg (67 to 0.013 kPa) as an absolute pressure. Such esterification or transesterification reaction and polycondensation reaction may be performed in one step or in multiple steps. The polyethylene terephthalate resin thus obtained has an intrinsic viscosity of usually 0.45 to 0.70 dl / g, and is chipped by a conventional method. The average particle diameter of this chip is usually in the range of 2.0 to 5.5 mm, preferably 2.2 to 4.0 mm.

  Next, the polymer obtained by melt polycondensation as described above is usually subjected to solid phase polymerization. A polymer chip subjected to solid phase polymerization may be subjected to solid phase polymerization after preliminarily crystallizing by heating to a temperature lower than the temperature at which solid phase polymerization is performed in advance. Such precrystallization includes (a) a method in which a dry polymer chip is heated at a temperature of usually 120 to 200 ° C., preferably 130 to 180 ° C. for 1 minute to 4 hours, and (b) a dry polymer chip. A method of heating the water in an atmosphere of water vapor or water vapor-containing inert gas at a temperature of usually 120 to 200 ° C. for 1 minute or longer, (c) a polymer chip that absorbs moisture in a water, water vapor or water vapor-containing inert gas atmosphere and adjusts the humidity Can be performed by a method of heating at a temperature of usually 120 to 200 ° C. for 1 minute or more. The humidity control of the polymer chip is carried out so that the moisture content is usually in the range of 100 to 10,000 ppm, preferably 1000 to 5000 ppm. By subjecting the conditioned polymer chip to crystallization or solid phase polymerization, it is possible to further reduce the amount of acetaldehyde contained in PET and impurities contained in a trace amount.

The solid phase polymerization step consists of at least one stage, and usually has a polymerization temperature of 190 to 230 ° C., preferably 195 to 225 ° C., usually 1 kg / cm ² G to 10 mmHg (absolute pressure 200 to 1.3 kPa), preferably 0. The reaction is carried out under a flow of inert gas such as nitrogen, argon, carbon dioxide or the like under conditions of a polymerization pressure of 5 kg / cm ² G to 100 mmHg (150 to 13 kPa as an absolute pressure). The solid phase polymerization time may be shorter as the temperature is higher, but is usually 1 to 50 hours, preferably 5 to 30 hours, and more preferably 10 to 25 hours. The intrinsic viscosity of the polymer obtained by solid phase polymerization is usually in the range of 0.70 to 0.90 dl / g.

  The intrinsic viscosity of the polyethylene terephthalate resin used in the present invention may be appropriately selected and determined, but is usually 0.5 to 2 dl / g, particularly 0.6 to 1.5 dl / g, particularly 0.7 to 1. It is preferably 0 dl / g. By setting the intrinsic viscosity to 0.5 dl / g or more, particularly 0.7 dl / g or more, the mechanical properties, residence heat stability, chemical resistance, and heat-and-moisture resistance tend to be improved in the resin composition of the present invention. And preferred. On the other hand, the intrinsic viscosity is preferably less than 2 dl / g, particularly less than 1.0 dl / g, which tends to improve the fluidity of the resin composition.

  In the present invention, the intrinsic viscosity of the polyethylene terephthalate resin is a value measured at 30 ° C. using a mixed solvent of phenol / tetrachloroethane (weight ratio 1/1).

  The density | concentration of the terminal carboxyl group of the polyethylene terephthalate resin used for this invention is 1-60microeq / g normally, and it is preferable that it is 3-50microeq / g especially 5-40microeq / g. When the terminal carboxyl group concentration is 60 μeq / g or less, the mechanical properties of the resin composition tend to be improved. Conversely, when the terminal carboxyl group concentration is 1 μeq / g or more, the heat resistance of the resin composition is increased. It is preferable because the thermal stability and hue tend to be improved.

  The terminal carboxyl group concentration of the polyethylene terephthalate resin can be determined by dissolving 0.5 g of polyethylene terephthalate resin in 25 mL of benzyl alcohol and titrating with a 0.01 mol / L benzyl alcohol solution of sodium hydroxide. it can.

  The polyethylene terephthalate resin used in the present invention is obtained by subjecting the above-described polyethylene terephthalate resin to a polycondensation catalyst deactivation treatment. There is no restriction | limiting in particular as a deactivation processing method of the polycondensation catalyst of a polyethylene terephthalate resin, A conventionally well-known deactivation process can be given according to the polycondensation catalyst used. Examples of the deactivation treatment method include the following methods.

Deactivation treatment method of polycondensation catalyst 1: Hot water (steam) treatment of germanium catalyst A method of deactivating the germanium catalyst in the polyethylene terephthalate resin by treating the polyethylene terephthalate resin with hot water (steam).
Specifically, the container is filled with polyethylene terephthalate resin, and steam of 70 to 150 ° C., for example, about 100 ° C. is steamed in an amount of 1 to 100% by weight per hour for 5 to 6000 minutes with respect to the polyethylene terephthalate resin. Dry after treatment.
The polyethylene terephthalate resin is immersed in distilled water 0.3 to 10 times the weight of the polyethylene terephthalate resin in the container, and then the container containing the polyethylene terephthalate resin and distilled water is heated from the outside, and the internal temperature is set to 70 to 110. The temperature is controlled at 3 ° C. and the mixture is kept for 3 to 3000 minutes for hot water treatment, then dehydrated and dried.
The said drying is normally performed for 3 to 8 hours at 120-180 degreeC in inert gas, such as nitrogen.

Deactivation treatment method 2 of polycondensation catalyst: Addition of phosphorus compound to titanium catalyst A phosphorus compound is added to a polyethylene terephthalate resin to deactivate the titanium catalyst in the polyethylene terephthalate resin. In this case, the amount of phosphorus atoms added is preferably in the range of 7 to 145 ppm based on the weight of the polyethylene terephthalate resin. When the addition amount of the phosphorus compound is less than 7 ppm, the deactivation of the catalyst is insufficient, and the intended effect of the present invention may not be obtained. When the addition amount of phosphorus atoms exceeds 145 ppm, the phosphorus compound itself becomes coarse aggregated particles, causing problems such as poor appearance and reduced impact resistance.

  In addition, as a phosphorus compound to add, conventionally well-known phosphate ester compounds, phosphite ester compounds, phosphonate compounds, etc. are mentioned. Among these, phosphonate compounds represented by the following general formula (3) are preferable.

R ¹ OC (O) XP (O) (OR ² ) ₂ (3)
Wherein R ¹ and R ² are alkyl groups having 1 to 4 carbon atoms, X is —CH ₂ — or —CH (Y) — (Y represents a phenyl group), and R ¹ and R ² are Each may be the same or different.)

  Among the phosphonate compounds represented by the above formula (3), alkyl phosphonate compounds are preferably exemplified, and among these, triethylphosphonoacetic acid is particularly preferable. These may be used alone or in combination of two or more.

  The deactivation treatment method of the polycondensation catalyst of the polyethylene terephthalate resin is an example of a deactivation treatment that can be adopted in the present invention, and the deactivation treatment according to the present invention is not limited to the above method.

  Hereinafter, the polyethylene terephthalate resin subjected to the deactivation treatment of the polycondensation catalyst is referred to as “deactivated PET”, and the untreated polyethylene terephthalate resin is referred to as “untreated PET”.

The deactivated PET used in the present invention is such that the polycondensation catalyst in the polyethylene terephthalate resin is deactivated as described above, so that the solid phase polymerization rate Ks calculated by the following formula (1) is 0.006 ( dl / g · hr) or less, particularly 0.005 (dl / g · hr) or less, and particularly about 0.001 to 0.004 (dl / g · hr) is preferable.
Solid-phase polymerization rate Ks = ([η] s− [η] m) / T (1)
Here, [η] s is the intrinsic viscosity (dl / g) of the polyethylene terephthalate resin after the polyethylene terephthalate resin is held at 210 ° C. for 3 hours under a nitrogen stream, and [η] m is the polyethylene terephthalate. It is the intrinsic viscosity (dl / g) of the polyethylene terephthalate resin after holding the resin at 210 ° C. for 2 hours under a nitrogen stream. T is 1 (hour). That is, in the present invention, the intrinsic viscosity after holding at 210 ° C. for 3 hours under a nitrogen stream is [η] s, and the intrinsic viscosity after holding for 2 hours under the same conditions is [η] m. The solid phase polymerization rate Ks calculated by the above-described equation (1) was used as the solid phase polymerization rate Ks. T is 1 hour.

  When the solid phase polymerization rate Ks of the deactivated PET exceeds 0.006 (dl / g · hr), the deactivation treatment of the polycondensation catalyst is insufficient, and the effect of suppressing the residence heat deterioration according to the present invention is sufficiently obtained. Can't get. However, it is difficult to make the solid phase polymerization rate Ks excessively small, and it is usually 0.001 (dl / g · hr) or more.

[Resin component]
The resin component which concerns on this invention is 95-51 mass% of the 1 type (s) or 2 or more types of the above-mentioned polycarbonate resin (A), and 5-49 masses of 1 type or 2 or more types of the above-mentioned deactivated PET (B). %.

When the proportion of the polycarbonate resin (A) in the resin component is larger than the above upper limit and the proportion of the deactivated PET (B) is smaller than the lower limit, the effect of improving chemical resistance and fluidity by using PET is sufficient. In addition, the conductivity development effect when carbon black is added cannot be sufficiently obtained.
On the other hand, when the proportion of the polycarbonate resin (A) is less than the above lower limit and the proportion of the deactivated PET (B) is more than the above upper limit, the original properties of the polycarbonate resin are impaired, and impact resistance and load heat deflection temperature are reduced. This is not preferable because the conductivity is not sufficiently obtained when carbon black is added.

  The preferable ratio of the resin component is polycarbonate resin (A) 90 to 55% by mass, deactivated PET (B) 10 to 45% by mass, more preferably polycarbonate resin (A) 85 to 60% by mass, deactivated PET ( B) It is 15-40 mass%.

[Carbon black (C)]
The carbon black (C) used as the conductive filler in the present invention is generally a conductive carbon black having a large specific surface area and a developed secondary aggregate (structure), preferably a specific surface area (BET type nitrogen adsorption method). There in a range of 30~1500m ² / g, inter alia 50~1300m ² / g, more preferably a 70~900m ² / g, especially 100~850m ² / g. When the specific surface area exceeds 1500 m ² / g, the fluidity and appearance of the resulting resin composition tend to deteriorate. When the specific surface area is less than 30 m ² / g, the conductivity may be difficult to be exhibited.

As the carbon black (C), dibutyl phthalate (DBP) absorption number of conductive carbon black 100~500cm ³ / 100g is preferably, among others 120~450cm ³ / 100g, especially 150~400cm ³ / 100g It is more preferable in terms of the balance between conductivity and impact resistance.

In the present invention, BET equation nitrogen adsorption method specific surface area ^(unit: m 2 / g), DBP absorption ^(unit: cm 3 / 100g) are those measured according to JIS K6217.

  Examples of such preferable conductive carbon black include a furnace method conductive carbon black in which raw material hydrocarbons are thermally decomposed by the combustion heat of crude oil or gas to generate carbon black, and a ketjen obtained by a heavy oil gasification process. Examples thereof include black and acetylene black obtained by pyrolyzing acetylene gas. For example, “Vulcan XC-72” manufactured by Cabot Corporation, “Ketjen Black EC” manufactured by Mitsubishi Chemical Corporation, “Denka” manufactured by Denki Kagaku Kogyo Co., Ltd. Black ", etc. are commercially available.

  One type of carbon black (C) may be used alone, or two or more types having different physical properties, raw materials, or manufacturing processes may be mixed and used.

  Carbon black (C) is 0.5 to 10 parts by mass, preferably 0.8 to 8 parts by mass, more preferably 100 parts by mass of the resin component consisting of polycarbonate resin (A) and deactivated PET (B). 1 to 6 parts by mass are used. If the blending amount of the carbon black (C) is less than the above lower limit, the conductivity of the resin composition is insufficient, and if it exceeds the upper limit, the fluidity, impact resistance and appearance of the resin composition are deteriorated.

[Thermal stabilizer (D)]
The resin composition of the present invention may contain a phosphorus-based heat stabilizer and / or a hindered phenol-based heat stabilizer with respect to the above-described resin component, and include these specific heat stabilizers (D). Thereby, the inhibitory effect of the residence heat deterioration by using deactivated PET as a polyethylene terephthalate resin (B) can be improved further notably, and the resin composition excellent in the residence heat deterioration resistance can be implement | achieved. That is, the thermal degradation can be suppressed by the phosphorus thermal stabilizer by the decomposition of the peroxide and the hindered phenol thermal stabilizer by capturing the peroxide radical.

  Examples of phosphorus heat stabilizers include phosphorus heat stabilizers such as phosphites and phosphates.

  Examples of phosphites include triphenyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, trinonyl phosphite, tridecyl phosphite, and trioctyl phosphite. , Trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tricyclohexyl phosphite, monobutyl diphenyl phosphite, monooctyl diphenyl phosphite, distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butyl Phenyl) pentaerythritol phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol phosphite, 2,2-methylenebis (4,6-di-tert) Butylphenyl) triesters of phosphorous acid such as octyl phosphite, diesters, monoesters, and the like.

  Examples of phosphate esters include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, tris (nonylphenyl) phosphate, 2-ethylphenyldiphenyl phosphate, tetrakis (2,4-di-). tert-butylphenyl) -4,4-diphenylphosphonite and the like.

  Among the above phosphorus-based heat stabilizers, distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol phosphite, bis (2,6-di-tert-butyl-4) -Methylphenyl) pentaerythritol phosphite, phosphite compounds such as tris (2,4-di-tert-butylphenyl) phosphite are preferred, and among them bis (2,6-di-tert-butyl-4-methylphenyl) Pentaerythritol phosphite and tris (2,4-di-t-butylphenyl) phosphite are particularly preferred.

  As the hindered phenol heat stabilizer, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl- 4-hydroxyphenyl) propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3 5-di-tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl)- 4-hydroxyphenyl] methyl] phosphoate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert Butyl-a, a ′, a ″-(mesitylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3 5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert -Butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol and the like.

  Among the above, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate is preferred. These two phenolic heat stabilizers are commercially available from Ciba Specialty Chemicals under the names “Irganox 1010” and “Irganox 1076”.

  A phosphorus heat stabilizer may be used individually by 1 type, and may use 2 or more types together. Moreover, about a hindered phenol-type heat stabilizer, 1 type may be used independently and 2 or more types may be used together. Moreover, you may use together a phosphorus thermal stabilizer and a hindered phenol thermal stabilizer.

  When a phosphorus heat stabilizer is used in the resin composition of the present invention, the phosphorus heat stabilizer is preferably 0 with respect to 100 parts by mass of the resin component composed of the polycarbonate resin (A) and the deactivated PET (B). 0.01 to 0.5 parts by mass, more preferably 0.02 to 0.2 parts by mass is used. When a hindered phenol heat stabilizer is used, the hindered phenol heat stabilizer is preferably added to the resin component 100 parts by mass composed of the polycarbonate resin (A) and the deactivated PET (B). 01 to 1 part by mass, more preferably 0.05 to 0.2 part by mass is used. When the blending amount of these heat stabilizers is not less than the above lower limit value, it is possible to sufficiently obtain the effect of suppressing the residence heat deterioration due to the blending of the heat stabilizer. Not economical. In addition, when using together a phosphorus heat stabilizer and a hindered phenol heat stabilizer, after making each heat stabilizer into the said mixing | blending range, a total compounding ratio is polycarbonate resin, deactivated PET resin, and It is preferable to use it so that it may become 0.07-0.4 mass part with respect to 100 mass parts of resin components which consist of.

[Rubber polymer (E)]
The resin composition of the present invention may further contain a rubbery polymer (E). By blending the rubbery polymer (E), the impact resistance and moldability are improved, and at the time of heat retention. The thickening of the resin composition can be suppressed. That is, by blending a suitable rubber polymer in an appropriate blending amount, the aggregation of the rubber polymer during heat retention is suppressed, and the thickening due to the aggregation of the rubber polymer is suppressed. The molding stability of the resin composition can be improved.

  The rubbery polymer used in the present invention is a rubbery polymer having a glass transition temperature of 0 ° C. or lower, particularly −20 ° C. or lower, or a copolymer obtained by copolymerizing a monomer component copolymerizable therewith. Any conventionally known compound that can be blended in a polycarbonate resin composition or the like to improve its mechanical properties can be used.

  Examples of rubber polymers include polybutadiene, polyisoprene, diene copolymers (styrene / butadiene copolymers, acrylonitrile / butadiene copolymers, acrylic / butadiene rubbers, etc.), ethylene and α-olefin copolymer Copolymers (ethylene / propylene copolymers, ethylene / butene copolymers, ethylene / octene copolymers, etc.), copolymers of ethylene and unsaturated carboxylic acid esters (ethylene / methacrylate copolymers, ethylene / butyl acrylate copolymers) Polymers), copolymers of ethylene and aliphatic vinyl compounds, terpolymers of ethylene, propylene and nonconjugated dienes, acrylic rubber (polybutyl acrylate, poly (2-ethylhexyl acrylate), butyl acrylate / 2-ethylhexyl) Acrylate copolymers), Corn-based rubber (a polyorganosiloxane rubber; polyorganosiloxane rubber and a polyalkyl (meth) consisting of acrylate rubber-IPN composite rubber etc.) and the like. These may be used alone or in combination of two or more. “(Meth) acrylate” means “acrylate” and “methacrylate”, and “(meth) acrylic acid” described later means “acrylic acid” and “methacrylic acid”.

  Preferred examples of the monomer component copolymerized with such a rubbery polymer include aromatic vinyl compounds, vinyl cyanide compounds, (meth) acrylic acid ester compounds, (meth) acrylic acid compounds, and the like. . Other monomer components include epoxy group-containing (meth) acrylic acid ester compounds such as glycidyl (meth) acrylate; maleimide compounds such as maleimide, N-methylmaleimide, N-phenylmaleimide; maleic acid, phthalic acid, itacon Examples thereof include α, β-unsaturated carboxylic acid compounds such as acids and anhydrides thereof, such as maleic anhydride. These monomer components may be used alone or in combination of two or more.

  In order to improve the molding stability of the resin composition of the present invention, it is particularly preferable to use a core / shell type graft copolymer type rubber polymer as the rubber polymer. In particular, at least one rubber polymer selected from butadiene-containing rubber, butyl acrylate-containing rubber, 2-ethylhexyl acrylate-containing rubber, and silicone-based rubber is used as a core layer, and an acrylic ester, a methacrylic ester, and a fragrance around the core layer. A core / shell type graft copolymer comprising a shell layer formed by copolymerizing at least one monomer component selected from an aromatic vinyl compound is particularly preferred. More specifically, methyl methacrylate-butadiene-styrene polymer (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene polymer (MABS), methyl methacrylate-butadiene polymer (MB), methyl methacrylate-acrylic rubber polymer ( MA), methyl methacrylate-acrylic butadiene rubber copolymer, methyl methacrylate-acrylic butadiene rubber-styrene copolymer, methyl methacrylate- (acrylic silicone IPN (interpenetrating polymer network) rubber) polymer, etc. Mention may be made of a core / shell type rubbery polymer comprising a polymethyl methacrylate (PMMA) -based polymerization or copolymer block.

  As such a core / shell type rubbery polymer, for example, Rohm and Haas Japan manufactured by Paraloid EXL2315, EXL2602, EXL2603, etc., KL series, KM330, KM336P, etc., KM series, KCZ201, etc., KCZ series, etc. And METABRENE S-2001 and SRK-200 manufactured by Mitsubishi Rayon.

  Other specific examples of the rubbery polymer obtained by copolymerizing a rubbery polymer with a monomer component copolymerizable therewith include polybutadiene rubber, styrene-butadiene copolymer (SBR), and styrene-butadiene-styrene. Block copolymer (SBS), styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), ethylene-ethyl acrylate copolymer (EEA), ethylene -A methyl acrylate copolymer (EMA) etc. are mentioned.

  These rubbery polymers may be used individually by 1 type, and may use 2 or more types together.

  When the rubbery polymer (E) is used in the resin composition of the present invention, the content of the rubbery polymer (E) in the resin composition of the present invention is such that the polycarbonate resin (A), the deactivated PET (B) and Preferably it is 1-15 mass parts with respect to 100 mass parts of resin components which consist of, More preferably, it is 2-12 mass parts, Most preferably, it is 3-10 mass parts. When the content of the rubbery polymer is equal to or higher than the above lower limit value, it is possible to sufficiently obtain an effect of improving the impact strength due to the blending of the rubbery polymer. Stiffness can be maintained well.

[Inorganic filler]
The resin composition of the present invention must contain the component (A), the component (B), and the component (C), but improves the dimensional stability, heat resistance, and rigidity of the resin composition. For the purpose, an inorganic filler other than the component (C) can be further contained.

  The inorganic filler used in the present invention is an inorganic compound powder other than the component (C). The form of the powder may be any of spherical, plate-like, needle-like, fiber-like, etc., but in order to improve the dimensional stability, heat resistance and rigidity of the finally obtained resin composition, it is plate-like Needles and fibers are preferred. Therefore, in the present invention, the shape of the inorganic filler is clearly distinguished into a spherical shape, a plate shape, a needle shape, and a fibrous shape as follows. In the case of a spherical shape, it includes not only a true spherical shape but also an elliptical cross section to some extent and an aspect ratio close to 1. In the case of a plate-like shape, it indicates a plate-like shape and has an aspect ratio (longest length of plate-like surface of plate-like powder / thickness of plate-like powder) in the range of 2-100. In the case of a needle shape, the length is 100 μm or less and the aspect ratio (particle length / particle diameter) is in the range of 2 to 20, and in the case of a fibrous shape, the length exceeds 100 μm. These can be easily distinguished by electron micrographs.

Specific examples of such plate-like, needle-like, and fibrous inorganic fillers include, as the plate-like filler, magnesium silicate such as talc, clay, mica, graphite, sericite, montmorillonite, plate-like calcium carbonate, There are plate-like alumina, glass flakes, etc., and acicular fillers include calcium silicate such as wollastonite, moss heidi, zonotlite, calcium titanate, aluminum borate, acicular calcium carbonate, acicular titanium oxide, tetrapot type zinc oxide Examples of the fibrous filler include glass fiber and carbon fiber. Among these inorganic fillers, talc, mica, glass flake, wollastonite, glass fiber, and carbon fiber are preferable in terms of the balance of impact resistance, dimensional stability, fluidity, and product appearance. From the viewpoint of product appearance, talc and wollastonite are preferable. In addition, about the details, such as a component, in the inorganic filler in this invention, for example, "filler utilization encyclopedia" (
(Filler Research Group, Taiseisha, 1994).

The average particle diameter of these inorganic fillers is preferably 0.1 to 25 μm, more preferably 0.5 to 15 μm in the case of plate-like and needle-like fillers. If the average particle size is less than 0.1 μm, the reinforcing effect tends to be insufficient, and if it exceeds 25 μm, the product appearance tends to be adversely affected. Here the average particle diameter refers to the D ₅₀ as measured in the liquid phase precipitation method using X-ray transmission. As an apparatus capable of performing such measurement, a Sedigraph particle size analyzer (manufactured by Micromeritics Instruments, model 5100) can be mentioned. Further, the fiber diameter of the fibrous filler is preferably 1 to 15 μm. If the fiber diameter is less than 1 μm, the reinforcing effect tends to be insufficient, and if it exceeds 15 μm, the product appearance tends to be adversely affected. In addition, the fiber diameter of a fibrous filler can be easily measured with an electron micrograph.

  The inorganic filler may be left untreated, but for the purpose of increasing the affinity with the resin component or the interfacial binding force, an inorganic surface treatment agent, a derivative such as a higher fatty acid or an ester salt thereof, aminosilane, epoxy For the purpose of improving the surface treatment with a coupling agent such as silane or the like, or improving the handleability, it may be used after being subjected to a focusing treatment with an acrylic resin, a urethane resin or the like. When surface treatment is performed in combination with various surfactants such as nonionic, cation and anionic types, and dispersants such as various resins, the viewpoint of improving mechanical strength and kneadability To preferred. In addition, the production method when pulverizing the inorganic filler such as talc from the raw stone is not particularly limited, but from the viewpoint of the handling of the inorganic filler, an aggregated state in which the bulk density is increased is preferable, which is deaerated and compressed. What was granulated using a thing and a binder is mentioned as a preferable thing.

  When an inorganic filler is blended in the resin composition of the present invention, the content of the inorganic filler in the resin composition of the present invention is 100 parts by mass of a resin component composed of polycarbonate resin (A) and deactivated PET (B). Is preferably 1 to 20 parts by mass, more preferably 2 to 15 parts by mass, and particularly preferably 3 to 10 parts by mass. When the content of the inorganic filler is equal to or higher than the above lower limit, the effect of improving the dimensional stability, heat resistance and rigidity due to the blending of the inorganic filler can be sufficiently obtained, and when the content is equal to or lower than the upper limit. A decrease in fluidity, impact strength, appearance, and conductivity can be prevented.

[Other ingredients]
In the resin composition of the present invention, the above-mentioned polycarbonate resin (A) and deactivated PET (B), carbon black (C), heat stabilizer (D), rubber properties are included within the range not impairing the effects of the present invention. In addition to the polymer (E) and the inorganic filler, other various additives contained in a normal polycarbonate resin composition may be contained.

  As various additives that can be contained, antioxidants, mold release agents, ultraviolet absorbers, dyes and pigments, reinforcing agents, flame retardants, impact resistance improvers, antistatic agents, antifogging agents, lubricants and antiblocking agents, Examples thereof include a fluidity improver, a plasticizer, a dispersant, and a fungicide. Two or more of these may be used in combination. Hereinafter, an example of an additive suitable for the resin composition of the present invention will be specifically described.

  The release agent includes at least one compound selected from the group consisting of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15000, and polysiloxane silicone oil. Can be mentioned.

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

  As the aliphatic carboxylic acid in the ester of an aliphatic carboxylic acid and an alcohol, the same one as the aliphatic carboxylic acid can be used. On the other hand, examples of the alcohol include saturated or unsaturated monovalent or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monovalent or polyvalent saturated alcohol having 30 or less carbon atoms is preferable, and an aliphatic saturated monohydric alcohol or polyhydric alcohol having 30 or less carbon atoms is more preferable. Here, aliphatic includes alicyclic compounds. Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol and the like. Is mentioned.

  In addition, said ester compound may contain aliphatic carboxylic acid and / or alcohol as an impurity, and may be a mixture of a some compound.

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

  Examples of the aliphatic hydrocarbon having a number average molecular weight of 200 to 15000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. Here, as the aliphatic hydrocarbon, alicyclic hydrocarbon is also included. Moreover, these hydrocarbon compounds may be partially oxidized. Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable. The number average molecular weight is preferably 200 to 5,000. These aliphatic hydrocarbons may be a single substance, or may be a mixture of various constituent components and molecular weights, as long as the main component is within the above range.

  Examples of the polysiloxane silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone. Two or more of these may be used in combination.

  When using a mold release agent, the content of the mold release agent in the resin composition of the present invention is usually 0.001 to 2 parts by mass with respect to 100 parts by mass in total of the polycarbonate resin (A) and the deactivated PET (B). The amount is preferably 0.01 to 1 part by mass. When the content of the release agent is not less than the above lower limit, the release effect is sufficient, and when it is not more than the above upper limit, degradation of hydrolysis resistance, mold contamination during injection molding, etc. can be prevented. it can.

  Specific examples of the ultraviolet absorber include organic ultraviolet absorbers such as benzotriazole compounds, benzophenone compounds, and triazine compounds in addition to inorganic ultraviolet absorbers such as cerium oxide and zinc oxide. Of these, organic ultraviolet absorbers are preferred. In particular, benzotriazole compounds, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2, 4-Dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2,2 ′-(1,4-phenylene) bis [4H-3,1-benzoxazine-4- ON], [(4-methoxyphenyl) -methylene] -propanedioic acid-dimethyl ester is preferred.

  Specific examples of the benzotriazole compound include condensates of methyl-3- [3-tert-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate-polyethylene glycol. Specific examples of other benzotriazole compounds include 2-bis (5-methyl-2-hydroxyphenyl) benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) benzotriazole, 2- (3 ′, 5′-di-tert-butyl-2′-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chloro Benzotriazole, 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- (3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy- 3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methyl Ren-bis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] [methyl-3- [3-tert-butyl-5- (2H- Benzotriazol-2-yl) -4-hydroxyphenyl] propionate-polyethylene glycol] condensate. Two or more of these may be used in combination.

  Of the above, preferably 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl]- 2H-benzotriazole, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2,4 -Dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol, 2,2'-methylene-bis [4- (1,1,3,3-tetramethylbutyl)- 6- (2N-benzotriazol-2-yl) phenol].

  When using the ultraviolet absorber, the content of the ultraviolet absorber in the resin composition of the present invention is usually 0.01 to 3 parts by mass with respect to 100 parts by mass in total of the polycarbonate resin (A) and the deactivated PET (B). The amount is preferably 0.1 to 1 part by mass. When the content of the ultraviolet absorber is at least the above lower limit, the effect of improving the weather resistance is sufficient, and when it is at most the upper limit, problems such as mold deposits can be prevented.

  Examples of the dye / pigment include inorganic pigments, organic pigments, and organic dyes. Examples of inorganic pigments include, for example, sulfide pigments such as carbon black, cadmium red, and cadmium yellow; silicate pigments such as ultramarine blue; zinc white, petal, chromium oxide, titanium oxide, iron black, titanium yellow, and zinc- Oxide pigments such as iron brown, titanium cobalt green, cobalt green, cobalt blue, copper-chromium black and copper-iron black; chromic pigments such as chrome lead and molybdate orange; Examples include Russian pigments. Organic pigments and organic dyes include phthalocyanine dyes such as copper phthalocyanine blue and copper phthalocyanine green; azo dyes such as nickel azo yellow; thioindigo, perinone, perylene, quinacridone, dioxazine, and isoindolinone. And condensed polycyclic dyes such as quinophthalone; anthraquinone, heterocyclic, and methyl dyes and the like. Two or more of these may be used in combination. Among these, carbon black, titanium oxide, cyanine-based, quinoline-based, anthraquinone-based, and phthalocyanine-based compounds are preferable from the viewpoint of thermal stability.

  When using a dye / pigment, the content of the dye / pigment in the resin composition of the present invention is usually 5 parts by mass or less, preferably 3 parts by mass with respect to 100 parts by mass in total of the polycarbonate resin (A) and the deactivated PET (B). Part or less, more preferably 2 parts by weight or less. When the content of the dye / pigment exceeds 5 parts by mass, the impact resistance may not be sufficient.

  Examples of the flame retardant include halogenated bisphenol A polycarbonate, brominated bisphenol epoxy resin, brominated bisphenol phenoxy resin, halogenated flame retardant such as brominated polystyrene, phosphate ester flame retardant, diphenylsulfone-3,3 ′. -Organic metal salt flame retardants such as dipotassium disulfonate, potassium diphenylsulfone-3-sulfonate, potassium perfluorobutanesulfonate, and polyorganosiloxane flame retardants are preferable, but phosphate ester flame retardants are particularly preferable. .

  Specific examples of the phosphate ester flame retardant include triphenyl phosphate, resorcinol bis (dixylenyl phosphate), hydroquinone bis (dixylenyl phosphate), 4,4′-biphenol bis (dixylenyl phosphate), bisphenol A Examples thereof include bis (dixylenyl phosphate), resorcinol bis (diphenyl phosphate), hydroquinone bis (diphenyl phosphate), 4,4′-biphenol bis (diphenyl phosphate), bisphenol A bis (diphenyl phosphate), and the like. Two or more of these may be used in combination. In these, resorcinol bis (dixylenyl phosphate) and bisphenol A bis (diphenyl phosphate) are preferable.

  When using a flame retardant, the content of the flame retardant in the resin composition of the present invention is usually 1 to 30 parts by mass, preferably 3 to 100 parts by mass in total of the polycarbonate resin (A) and the deactivated PET (B). -25 mass parts, More preferably, it is 5-20 mass parts. Sufficient flame retardancy is obtained when the content of the flame retardant is equal to or higher than the lower limit, and a decrease in heat resistance can be prevented when the content is lower than the upper limit.

  Examples of the anti-dripping agent include fluorinated polyolefins such as polyfluoroethylene, and polytetrafluoroethylene having fibril forming ability is particularly preferable. This shows the tendency to disperse | distribute easily in a polymer and to couple | bond together polymers and to make a fibrous material. Polytetrafluoroethylene having fibril-forming ability is classified as type 3 according to the ASTM standard. Polytetrafluoroethylene can be used in solid form or in the form of an aqueous dispersion. Examples of polytetrafluoroethylene having fibril-forming ability include “Teflon (registered trademark) 6J” or “Teflon (registered trademark) 30J” from Mitsui DuPont Fluorochemical Co., Ltd. and “Polyflon (trade name) from Daikin Industries, Ltd. Is commercially available.

  When using a dripping inhibitor, the content of the dripping inhibitor of the resin composition of the present invention is usually 0.02 to 4 parts by mass with respect to 100 parts by mass in total of the polycarbonate resin (A) and the deactivated PET (B). The amount is preferably 0.03 to 3 parts by mass. When there are too many compounding quantities of a dripping prevention agent, the fall of a molded article appearance may arise.

  The resin composition according to the present invention may contain other resin components and rubber components other than the polycarbonate resin (A) and deactivated PET (B) and the rubber polymer (E) described above. . In this case, as other resin or rubber component, for example, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, styrene resin such as polystyrene resin, polyolefin resin such as polyethylene resin and polypropylene resin, polyamide resin , Polyimide resin, polyetherimide resin, polyurethane resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, polymethacrylate resin, phenol resin, epoxy resin, etc., but the content of these other resins or rubber components is In order to sufficiently secure the effect of the combined use of the polycarbonate resin (A) and the deactivated PET (B), 20 parts by mass with respect to a total of 100 parts by mass of the polycarbonate resin (A) and the deactivated PET (B). Less than It is preferable that the.

[Method for Producing the Resin Composition of the Present Invention]
The resin composition of the present invention comprises polycarbonate resin (A), deactivated PET (B), carbon black (C), heat stabilizer (D) used as necessary, rubbery polymer (E), other It can be produced by appropriately selecting any conventionally known method using an additive.

  Specifically, polycarbonate resin (A), deactivated PET (B), carbon black (C), and other additives are mixed in advance using various mixers such as a tumbler and a Henschel mixer, and then a Banbury mixer, roll The resin composition can be produced by melt-kneading with a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, a kneader or the like. Moreover, it is also possible to produce a resin composition without mixing each component in advance, or by mixing only some components in advance and supplying them to an extruder using a feeder and melt-kneading them.

  The resin composition of the present invention is preferably produced by a production method for satisfying suitable characteristics of the resin composition of the present invention described later.

[Preferable characteristics of the resin composition of the present invention]
The resin composition of the present invention is excellent in suppression of residence heat deterioration due to the use of deactivated PET, and is excellent in conductivity and its stability. The preferable one is that the volume resistivity change calculated by the following formula (2) is used. It shows good characteristics of 3 or less.
Volume resistivity change = [R _x ] / [R _o ] (2)
(However, in the above formula (2), [R _x ] is the volume resistivity of a molded product that is injection-molded after the resin composition is retained in an injection molding machine at 280 ° C. for 20 minutes, and [R ₀ ] is (The volume resistivity of each of the molded products obtained by injection molding immediately after the resin composition is injected into the injection molding machine is shown.)

  If the resin composition has a volume resistivity change of 3 or less, particularly 2 or less, the resin composition is excellent in staying heat stability and conductivity performance, and is stable and continuously produced. can do.

  In order to obtain such a resin composition, it is important to improve the dispersion of carbon black (C) in the resin composition and to remove elements that destabilize dispersion by heating. That is, in the resin composition of the present invention, the two resin components of the polycarbonate resin (A) and the polyethylene terephthalate resin (B) maintain a stable morphology with respect to the thermal history, as well as the conductive carbon. It is important to disperse the black (C) in the resin composition so that the shape of the black (C) remains intact and a conductive path can be stably formed.

  Thus, as a method of disperse | distributing carbon black (C) favorably in a resin composition, the method of using a dispersing agent and the method of adjusting kneading | mixing conditions are mentioned. In particular, as a kneading condition, an appropriate kneading, that is, in a kneading step of the resin composition in order to disperse the carbon black (C) primary particle aggregate structure (structure) in the resin composition as much as possible. And a method of side-feeding carbon black (or carbon black masterbatch).

  In general, in a method for producing a resin composition, raw materials for the resin composition are charged into a kneader, and these are first melted and kneaded. The kneading step is generally provided a plurality of times. Specifically, for example, as a step inside a general kneader, the raw material melting step is performed in order from the raw material charging side (upstream side) of the resin composition. The resin composition is manufactured through a kneading step, a conveying step, and a kneading step.

  In order to obtain a resin composition having a volume resistivity change of 3 or less, carbon black is side-fed in this melt-kneading step, and at this time, a shearing force is applied as in the above-mentioned “conveying step”, that is, the kneading step. There is a method in which the molten resin is first brought into contact with the molten resin for a certain period of time and then the resin composition containing the carbon black is kneaded, whereby a resin composition having excellent performance can be obtained.

  The conditions after the side feed at this time are as follows: 0.5 to 10 parts by mass of carbon black (C) with respect to 100 parts by mass of the resin component charged from the upstream side is 0. The condition of kneading after contacting with the molten resin in the range of 5 to 10 seconds is mentioned. In this way, the resin composition is maintained while maintaining the structure of the primary particles of the carbon black (C) by performing kneading after contacting with the molten resin for a certain period of time without performing kneading for a long time by side feed. It can be dispersed well inside.

The degree of conductivity of the resin composition of the present invention is 1.0 × 10 ⁸ Ωcm or less, for example, as a volume resistivity value measured by the measurement method described in the Examples section below. Assuming the case of an electromagnetic wave shield, a resin molded product for electrostatic coating, etc., it is preferably about 1.0 × 10 ^{1 to} 1.0 × 10 ⁷ Ωcm.

Further, the degree of fluidity of the resin composition of the present invention is measured by the measuring method described in the section of the examples described later. MVR (melt volume rate) 5 to 30 cm ³ / 10min as the value of, in particular 7~25cm ³ / 10min, it is preferable that especially 9~20cm ³ / 10min.
When the MVR of the composition of the present invention is not more than the above upper limit value, the impact resistance and moist heat resistance are good, and when it is not less than the above lower limit value, the fluidity becomes good, the residual strain is suppressed, and the chemical resistance A molded product having excellent properties can be obtained.

[Production method of resin molded product]
The method for producing a molded article from the resin composition of the present invention is not particularly limited, and a molding method generally employed for thermoplastic resins, that is, a general injection molding method, an ultra-high speed injection molding method, an injection Compression molding method, multicolor injection molding method, gas-assisted injection molding method, molding method using heat insulation mold, molding method using rapid heating / cooling mold, foam molding (including supercritical fluid), insert molding, IMC (In-mold coating molding) A molding method, an extrusion molding method, a sheet molding method, a thermoforming method, a rotational molding method, a lamination molding method, a press molding method, or the like can be employed. Also, in various injection molding methods, a molding method using a hot runner method can be selected.

  Further, the resin composition of the present invention can be subjected to multicolor composite molding with other thermoplastic resin compositions to form a composite molded product.

  In the present invention, the polyethylene terephthalate resin (B) is combined with the polycarbonate resin (A) by using inactivated PET as the polyethylene terephthalate resin (B), and preferably further blending a specific heat stabilizer (D). Residual heat deterioration of the resin composition due to the formation of the resin composition is suppressed, so that the problem of residence heat deterioration in the molding process is prevented, but if this residence temperature is excessively high and the residence time is excessively long, There is a risk of thermal degradation. Therefore, the residence temperature of the resin composition in the molding step of the resin composition of the present invention is preferably 280 ° C. or less and the residence time is 20 minutes or less.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
The raw material components used in the following examples and comparative examples are as follows.

[Polycarbonate resin]
(1) PC-A:
Bisphenol A-type aromatic polycarbonate produced by the interfacial polymerization method “Iupilon (registered trademark) E-2000” manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight: 28,000, terminal hydroxyl group content: 150 ppm

(2) PC-B:
Bisphenol A-type aromatic polycarbonate produced by the interfacial polymerization method "Iupilon (registered trademark) S-3000" manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight: 22,000, terminal hydroxyl group content: 150 ppm

(3) PC-C:
Bisphenol A-type aromatic polycarbonate produced by the interfacial polymerization method “Iupilon (registered trademark) H-3000” manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight: 18,000, terminal hydroxyl group content: 150 ppm

[Polyethylene terephthalate resin]
(1) Untreated PET-1:
Polyethylene terephthalate using a germanium dioxide catalyst as a polycondensation catalyst “GG500S” manufactured by Mitsubishi Chemical Corporation, intrinsic viscosity [η]: 0.76 dl / g, terminal carboxyl group concentration AV: 28 μeq / g, ET ratio: 97.8 Equivalent%, solid phase polymerization rate Ks: 0.0085 dl / g · hr (physical property values are all based on the measurement method described later.)

(2) Untreated PET-2:
Polyethylene terephthalate using a titanium-based catalyst as a polycondensation catalyst "Novapex (registered trademark) RF543DE" manufactured by Mitsubishi Chemical Corporation, intrinsic viscosity [η]: 0.74 dl / g, terminal carboxyl group concentration AV: 8.4 μeq / g ET ratio: 97.6 equivalent%, solid phase polymerization rate Ks: 0.0078 dl / g · hr (all physical property values are according to the measurement method described later)

(3) Inactivated PET-1:
The above-mentioned untreated PET-1 was subjected to the deactivation treatment of the following polycondensation catalyst, intrinsic viscosity [η]: 0.75 dl / g, terminal carboxyl group concentration AV: 30 μeq / g, ET ratio: 97 .8 equivalent%, solid phase polymerization rate Ks: 0.0031 dl / g · hr (physical property values are all based on the measurement method described later.)
<Deactivation treatment method>
50 kg of untreated PET-1 was boiled in 50 kg of distilled water at 100 ° C. for 1 hour, dehydrated, and dried at 120 ° C. for 6 hours in a nitrogen atmosphere.

(4) Inactivated PET-2:
The above-mentioned untreated PET-2 was subjected to the following polycondensation catalyst deactivation treatment, intrinsic viscosity [η]: 0.73 dl / g, terminal carboxyl group concentration AV: 12 μeq / g, ET ratio: 97 .6 equivalent%, solid phase polymerization rate Ks: 0.0042 dl / g · hr (physical property values are all determined by the measurement method described later.)
<Deactivation treatment method>
0.01 parts by mass of the following phosphorus-based thermal stabilizer a (Adeka Stab AX-71) and 0.03 parts by mass of the following phosphorus-based thermal stabilizer b (Irgaphos 168) with respect to 100 parts by mass of untreated PET-2. After adding a part and mixing uniformly with a tumbler mixer, using a twin screw extruder (manufactured by Nippon Steel Works, TEX30XCT, L / D = 42, barrel number 12), cylinder temperature 270 ° C., screw rotation speed 200 rpm, discharge Inactivated PET-2 pellets were prepared by feeding to an extruder from a barrel at an amount of 15 kg / hr, and melt-kneading.
Phosphorus heat stabilizer a: “ADEKA STAB AX-71” (mono or di-stearyl acid phosphate) manufactured by ADEKA
Phosphorus-based thermal stabilizer b: “Irgaphos 168” (Tris (2,4-di-t-butylphenyl) phosphite) manufactured by Ciba Specialty Chemicals

[Carbon black]
(1) CB-1
Mitsubishi Chemical Corporation product "Mitsubishi Carbon Black # 3400 b", the specific surface area (BET equation nitrogen adsorption method): 165m ² / g, a dibutylphthalate (DBP) ^absorption: 175cm 3 / 100g

(2) CB-2
Mitsubishi Chemical Corporation product "Mitsubishi Carbon Black # 3030B", the specific surface area (BET equation nitrogen adsorption method): ^32m 2 / g, a dibutylphthalate (DBP) ^absorption: 130 cm 3/100 g

(3) CB-3
Denki Kagaku Kogyo Co., Ltd. product "Denka Black", the specific surface area (BET equation nitrogen adsorption method): ^69m 2 / g, a dibutylphthalate (DBP) ^absorption: 160cm 3 / 100g

(4) CB-4
Mitsubishi Chemical Corporation products "Ketchen Black EC-300J", the specific surface area (BET equation nitrogen adsorption method): 800m ² / g, dibutyl phthalate (DBP) absorption ^amount: 360cm 3 / 100g

[Rubber polymer]
Core / shell type graft copolymer consisting of polyalkyl acrylate (core) / alkyl acrylate / alkyl methacrylate copolymer (shell) "Paralloid EXL2315" manufactured by Rohm and Haas Japan

[Thermal stabilizer]
(1) Heat stabilizer-1 (phosphorus heat stabilizer)
Tris (2,4-di-tert-butylphenyl) phosphite “Irgaphos 168” manufactured by Ciba Specialty Chemicals

(2) Heat stabilizer-2 (hindered phenol heat stabilizer)
Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate “Irganox 1076” manufactured by Ciba Specialty Chemicals

In addition, evaluation methods for various physical properties and characteristics are as follows.
<Terminal carboxyl group concentration of PET>
Weigh 0.5 g of resin chips accurately, dissolve in 25 ml of benzyl alcohol at 195 ° C., cool in ice water for several tens of seconds, add 2 ml of ethyl alcohol, and use an automatic titrator (“AUT-301” manufactured by Toa Denpa). And neutralized titration with 0.01N NaOH benzyl alcohol solution. From the measurement titration amount A (ml), the blank titration amount B (ml), the titer F of NaOH benzyl alcohol, and the weighed value W (g) of the sample, the amount of terminal carboxyl group AV (μeq / g) according to the following formula: Asked.
AV = (A−B) × 0.01 × F × 1000 / W

<Intrinsic viscosity of PET>
A solution having a concentration (c) of 1.0 g / dl was prepared using 0.50 g of freeze-pulverized PET sample using a mixed solution of phenol / tetrachloroethane (weight ratio 1/1) as a solvent. Here, the sample was dissolved at 120 ° C. for 30 minutes. The relative viscosity (η _rel ) of this solution was measured at 30 ° C. using an Ubbelohde viscometer with respect to the solvent alone (c = 0), and this relative viscosity (η _rel ) −1 was _defined as the specific viscosity (η _sp ). The ratio (η _sp / c) to the concentration (c) was determined. Similarly, the concentration (c) is 0.5 g / dl, 0.2 g / dl, and 0.1 g / dl, and the respective ratios (η _sp / c) are obtained. From these values, the concentration (c) is set to 0. The ratio (η _sp / c) when extrapolated to was calculated as intrinsic viscosity [η] (dl / g).

<Composition analysis of PET>
Using a 3% by weight solution of a resin sample dissolved in deuterated trifluoroacetic acid at room temperature, ¹ H-NMR was measured with a nuclear magnetic resonance apparatus (“JNM-EX270 type” manufactured by JEOL Ltd.). Assign the peak, determine the proportion of terephthalic acid and dicarboxylic acid components other than terephthalic acid, and ethylene glycol and other diol components from the integral ratio, and the content of oxyethyleneoxyterephthaloyl units (ET ratio) ) Was calculated.

<Solid-state polymerization rate of PET>
10 g of PET chip cut so that the average grain weight per grain becomes 24 mg is put in a container made of stainless steel mesh with a diameter of 30 mmφ and a height of 30 mm, and an inert oven (“IPHH-201 type” manufactured by ESPEC) It was dried at 160 ° C. for 4 hours under a nitrogen stream of 40 liters / minute. Thereafter, the temperature was raised from 160 ° C. to 210 ° C. over 1 hour while maintaining the nitrogen flow, and from the intrinsic viscosity [η] s after 3 hours after holding at 210 ° C., from the intrinsic viscosity [η] m after 2 hours. It was calculated by the following equation (1).
Solid phase polymerization rate Ks = ([η] s− [η] m) / 1 (1)

[Examples 1 to 16, Comparative Examples 1 to 6]
<Preparation of Resin Compositions of Examples 1-15 and Comparative Examples 1-6>
Using the raw material components, conductive thermoplastic resin compositions containing the proportions shown in Tables 1 and 2 below were prepared as follows.

  That is, after each component shown in Tables 1 and 2 is uniformly mixed with a tumbler-mixer at the ratio shown in Tables 1 and 2, it is fed to a twin-screw extruder (“TEX30XCT” manufactured by Nippon Steel) and melted. The kneaded resin composition was quenched in a water tank and pelletized using a pelletizer to obtain resin composition pellets.

<Preparation of Resin Composition of Example 16>
Each component other than carbon black shown in Table 2 was uniformly mixed with a tumbler-mixer at the ratio shown in Table 2, and then fed to a twin-screw extruder (“TEX30XCT” manufactured by Nippon Steel Works). The resin composition side-feeded from the middle of the same extruder as shown in Table 2 and melt-kneaded was rapidly cooled in a water tank, and pelletized using a pelletizer to obtain pellets of the resin composition. In addition, the arrival time from the side feed to the kneading zone immediately below (the time for the conveyance process) was 5 seconds.

<Evaluation of resin composition>
The resin composition obtained above was evaluated as follows, and the results are shown in Tables 1 and 2.

(1) Notched Charpy impact strength After drying the resin composition pellets at 120 ° C for 5 hours or more, using a FANUC "α100iA type" injection molding machine, cylinder temperature 280 ° C, mold temperature 80 ° C, molding An ISO tensile test piece (thickness: 4.0 mm) was injection molded under a cycle of 40 seconds. In accordance with ISO 179, a test piece with a thickness of 4.0 mm (ordinary test piece) is prepared from this test piece, and the notched Charpy impact strength (unit: kJ / m ² ) is measured under an environment of 23 ° C. It was measured.
In addition, about the measurement of the Charpy impact strength with a notch after residence, the test piece with a notch (test piece after a residence) is produced similarly to the above from the test piece after residence for 20 minutes obtained by the method of (2) described later. In a 23 ° C. environment, the notched Charpy impact strength (unit: kJ / m ² ) was measured.

(2) Appearance after retention After drying the resin composition pellets at 120 ° C. for 5 hours or more in the same manner as in (1) above, using a FANUC “α100iA type” injection molding machine, the cylinder temperature is 280 ° C., gold Under the condition of a mold temperature of 80 ° C., sufficient measurement for injection molding was performed, and after holding for 20 minutes in the cylinder, injection molding was performed to prepare an ISO tensile test piece (thickness: 4.0 mm) after residence.
The appearance of the obtained test piece after residence was evaluated in the following four stages.
◎: No silver streak on the surface ○: Slight silver streak on the surface △: Silver streak on the surface ×: Silver streak on the surface is remarkable

(3) Conductivity (volume resistivity)
For the normal test piece and the post-dwelling test piece obtained by the above method (1), both ends of the parallel part are cut so as to be 50 mm in length, and silver paste is applied to the both end faces generated by the cutting. After drying at room temperature, the resistance value (RL: unit Ω) between the both end faces was measured with a tester, and the volume resistivity R (unit: Ωcm) was calculated from the following equation.
R = RL × AL / L
(In the formula, AL means the cross-sectional area of the test piece (unit: cm ² ), and L means the length of the test piece (unit: cm).)
From the measured volume resistivity [R _o ] of the normal test piece and the volume resistivity [R _x ] of the post-dwelling test piece, the change rate was calculated by the following equation.
Volume resistivity change = Volume resistivity [R _x ] of test piece after residence / Volume resistivity [R _o ] of normal test piece

(4) Mold release resistance In the above (1), after the pellets of the resin composition are dried at 120 ° C. for 5 hours or more, using a “α100iA type” injection molding machine manufactured by FANUC, cylinder temperature 280 ° C., mold temperature When an ISO tensile test piece (thickness: 4.0 mm) was injection-molded under the conditions of 80 ° C. and a molding cycle of 40 seconds, the release resistance of the test piece from the mold was evaluated in the following four stages.
A: No problem with releasability ○: Slight resistance when releasing (visually)
Δ: Slightly deformed specimen when released ×: Poor release (not released, large deformation of specimen)

(5) MVR of resin composition
The MVR (melt volume rate) was measured at a temperature of 300 ° C. and a load of 11.8 N for the normal test piece and the post-staying test piece obtained by the method (1), respectively, according to JIS K7210.

<Discussion>
Tables 1 and 2 show the following.

Even when deactivated PET is used, in Comparative Examples 1 and 2 in which the ratio of the polyethylene terephthalate resin is large and the polycarbonate resin is small, the fluidity is good, but the impact resistance, conductivity, and release resistance are poor.
In Comparative Examples 3 and 4 using untreated PET instead of deactivated PET as the polyethylene terephthalate resin, the volume resistivity change is large, the stability of the conductive performance is poor, and the impact resistance and the appearance after residence are also poor.
In Comparative Example 5 in which the amount of carbon black is too large, the conductivity is good, but the fluidity, impact resistance, and appearance after residence are poor.
In Comparative Example 6 where the amount of carbon black is too small, practical conductivity is not exhibited.

  On the other hand, good evaluation results are obtained in Examples 1 to 16 in which polycarbonate resin and deactivated PET are included in a predetermined ratio as resin components and carbon black is included within the scope of the present invention.

Claims (7)

  Carbon black (C) 0.5-10 mass part is mix | blended with 100 mass parts of resin components which consist of polycarbonate resin (A) 95-51 mass% and polyethylene terephthalate resin (B) 5-49 mass%. A conductive thermoplastic resin composition, wherein the polyethylene terephthalate resin (B) is a polyethylene terephthalate resin that has been subjected to a deactivation treatment of a polycondensation catalyst. Polyethylene terephthalate resin that has been subjected to the deactivation treatment of the polycondensation catalyst has a terminal carboxyl group concentration of 5 to 40 μeq / g, an intrinsic viscosity [η] of 0.6 to 1.5 dl / g, and oxyethyleneoxy with respect to all constituent repeating units. The ratio of terephthaloyl units is 90 equivalent% or more, and the solid-state polymerization rate Ks calculated by the following formula (1) is 0.006 (dl / g · hr) or less. The electrically conductive thermoplastic resin composition as described.
Solid-phase polymerization rate Ks = ([η] s− [η] m) / T (1)
(Where [η] s is the intrinsic viscosity (dl / g) of the polyethylene terephthalate resin after holding the polyethylene terephthalate resin at 210 ° C. for 3 hours under a nitrogen stream, and [η] m is a nitrogen stream. (Inherent viscosity (dl / g) of the polyethylene terephthalate resin after being kept at 210 ° C. for 2 hours, T is 1 (hour).) It claims a specific surface area of the carbon black (C) (BET equation nitrogen adsorption method) 30~1500m ² / g, and a dibutyl phthalate (DBP) absorption is characterized by a 100~500cm ³ / 100g 1 or 2 The conductive thermoplastic resin composition described in 1.   Furthermore, 0.01 to 0.5 parts by mass of a phosphorus-based heat stabilizer and / or hindered as a heat stabilizer (D) with respect to 100 parts by mass in total of the polycarbonate resin (A) and the polyethylene terephthalate resin (B). The conductive thermoplastic resin composition according to claim 1, comprising 0.01 to 1 part by mass of a phenol-based heat stabilizer.   Furthermore, 1-15 mass parts of rubbery polymers (E) are contained with respect to a total of 100 mass parts of polycarbonate resin (A) and polyethylene terephthalate resin (B), Any one of Claim 1 thru | or 4 characterized by the above-mentioned. The conductive thermoplastic resin composition according to claim 1. 6. The conductive thermoplastic resin composition according to claim 1, wherein the volume resistivity change calculated by the following formula (2) is 3 or less.
Volume resistivity change = [R _x ] / [R _o ] (2)
(However, in the above formula (2), [R _x ] is the volume resistivity of a molded product that is injection-molded after the resin composition is retained in an injection molding machine at 280 ° C. for 20 minutes, and [R ₀ ] is (The volume resistivity of each of the molded products obtained by injection molding immediately after the resin composition is injected into the injection molding machine is shown.)   A resin molded product obtained by injection molding the conductive thermoplastic resin composition according to any one of claims 1 to 6.