JP2008063569A - Conductive resin composition and molded product formed by molding the same - Google Patents

Abstract

【Task】
Providing a conductive resin composition with reduced odor and a molded article using the resin composition.
[Solution]
For 100 parts by weight of resin component (C) containing 50 to 92% by weight of polyphenylene ether (A) and 50 to 8% by weight of styrene resin (B), 50 to 200 parts by weight of stainless microfiber (D) and the following formula A conductive resin composition comprising 0.1 to 5.0 parts by weight of the synthetic zeolite (E) represented by (1).
_{M 2 / n O · Al 2} O 3 · xSiO 2 · yH 2 O (1)
(Wherein, M represents a monovalent or divalent metal capable of ion exchange, n represents the valence of the metal, and x represents a silica coefficient (SiO ₂ / Al ₂ O ₃ molar ratio) of 10 to 10. 500 represents the number, y is the number of water of crystallization, and represents a number of 0 to 7.)
[Selection figure] None

Description

  The present invention relates to a novel conductive resin composition, and more specifically, at the time of melt-kneading a polyphenylene ether resin composition containing a styrenic resin (hereinafter sometimes abbreviated as a modified polyphenylene ether resin) or a high temperature of a molded product. Concerning conductive resin compositions that reduce odors generated during heating and suppress the adhesion of dust and dust, and molded products such as storage containers for electric and electronic parts and transport trays formed by molding the resin compositions It is.

In recent years, electric / electronic / OA devices have been reduced in size, weight, integration, and accuracy, and accordingly, there has been an increasing demand to reduce the adhesion of dust and dust to electric / electronic components as much as possible. In the first place, if dust or dust adheres to electrical and electronic parts, it will cause problems such as poor contact and reading errors, so it inherently dislikes the adhesion of dust and dust, but especially the recent reduction in size and weight of electrical and electronic parts. Demands are becoming stricter due to higher integration and higher accuracy. For example, wafers used for semiconductors, IC chips, digital cameras, solid-state imaging devices such as CCD image sensors and CMOS image sensors used for video cameras, and internal components of hard disks used for computers are the best examples. The manufacture and assembly of these electric and electronic parts are usually performed in a so-called clean room where dust and dust are extremely small, and dust and dust do not adhere here. However, during transportation of electrical and electronic parts, since it is exposed to the outside air, adhesion of dust and dust becomes a problem. In order to avoid this problem, it is required to use a resin material imparted with conductivity to parts for transporting and storing electrical and electronic parts (IC and CCD trays, cases, housings, etc.).

On the other hand, the production of the resin composition and the processing such as injection molding are usually performed at a high temperature. For example, 200 to 280 ° C. for styrene-based resins, 260 to 360 ° C. for polyphenylene ether, and 240 to 350 for modified polyphenylene ether resins. It is often in a molten state at a high temperature of ℃.
Furthermore, molded articles obtained by molding such a resin composition are often exposed to high temperatures in the course of use. For example, in the case where the molded product is a tray used in IC and CCD manufacturing processes and transportation processes, slight moisture contained in the IC and CCD, and volatility such as alkali ions, Br ions, and Cl ions. In order to degas and remove (bake) impurities, ICs and CCDs are placed in the tray and heated in a baking room set at a temperature of 130 ° C. or higher. If moisture or a gas component remains in the IC or CCD, it causes a fatal defect in the accuracy of the IC or CCD. Therefore, it is necessary to sufficiently heat the baking process. Recently, in order to improve the reliability of ICs and CCDs, the baking temperature tends to rise to 150 ° C. or higher.

  In addition, at the time of high temperature heating such as melt kneading and molding of the resin composition or baking of the molded product, (1) odor derived from a small amount of production raw material remaining in the resin, (2) due to thermal decomposition of the resin Odor, (3) Odor due to thermal decomposition or vaporization of the additive is generated. And there exists a problem that such an odor damages the manufacturing chamber of a resin composition, a molding processing chamber, and the surrounding environment. Further, this odor is brought into a clean room where ventilation is restricted together with a molded product such as an IC or CCD tray, and there is a problem that it causes a significant discomfort to an assembly operator of electrical and electronic parts. Therefore, a low-odor conductive resin composition is required for a tray for transporting electrical and electronic parts.

In order to impart conductivity to the modified polyphenylene ether resin, it is widely practiced to mix conductive carbon black and metal fibers. Examples of the modified polyphenylene ether resin containing conductive carbon black include Patent Documents 1 and 2, but have the following drawbacks. (1) Detachment of carbon black due to wear during molding contact or friction (so-called “carbon black peeling”), and the desorbed carbon black is used in IC and CCD chips, wafers, and hard disks used in computers. Adhering to internal parts of the product causes malfunction. (2) Odor is generated when the resin composition or molded product is heated to a high temperature. (3) The mechanical strength is lowered, the moldability is lowered, and the appearance of the molded product is deteriorated due to the exposure of carbon black. (4) Since only a black resin composition can be obtained, it is impossible to identify molded products by coloring them in various hues.
In addition, when metal fibers longer than 1 mm are blended in the resin, poor dispersion due to entanglement of the metal fibers is likely to occur, resulting in conductive variation and gate clogging.
Although the resin composition which mix | blended the metal fiber of 1 mm or less is disclosed in patent document 3 as an electroconductive resin composition which solved the various problems by said carbon black, and the poor dispersion | distribution of metal fiber, in patent document 3, Even the metal fibers used have a long length, gate clogging occurs, and the problem of odor generated when a resin composition or a molded product is heated to a high temperature has not been solved.

  For the purpose of solving the odor problem, a synthetic polyphenylene ether resin is synthesized with carbon black and a water adsorption capacity of 20% by weight or more under conditions of a pore diameter of 0.8 nm or more, temperature of 25 ° C./relative humidity of 10% / normal pressure. A resin composition (patent document 4) containing zeolite is disclosed. However, with respect to the synthetic zeolite described in Patent Document 4, attention is paid only to the water adsorption ability, and the silica coefficient and the amount of water of crystallization of the zeolite are not paid attention, and are not specifically described. In addition, only examples using hydrophilic zeolites with low silica modulus are described.

  Patent Document 5 discloses an additive for a resin containing, as a main component, an inorganic powder capable of deodorizing and removing odors generated during kneading and molding of a resin composition. As, it is disclosed to use an aluminosilicate having silica, metal oxide and alumina in a specific ratio. However, in the resin composition containing the resin additive specifically described in Patent Document 5, there is no description regarding the appearance of the molded product and the mechanical strength, and the inorganic powder used in the examples Had a low silica coefficient.

JP-A-2-175754 JP 2004-263016 A Japanese Patent Laid-Open No. 2-178336 JP 07-138466 A Japanese Patent Laid-Open No. 11-293032

When the inventor of the present application further examined the above Patent Document 4, when synthetic zeolite having a moisture adsorption capacity of 20% by weight or more described in Patent Document 4 is used, silver is generated on the surface of the molded product, Only a molded product having an inferior appearance was obtained, and the problem of carbon black peeling was not solved.
Moreover, when this inventor examined further about the resin composition of patent document 5, it turned out that the problem of peeling of an inorganic powder is not solved.
The problem to be solved by the present invention is that it can be colored in a hue other than black without impairing the original properties of the modified polyphenylene ether resin, the appearance of the molded product is excellent, and when the resin is melt-kneaded and molded. An object of the present invention is to provide a conductive resin composition in which generation of odor is reduced during high-temperature heating or high-temperature heating of a resin molded product, and a molded product using the resin composition.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have obtained a synthetic zeolite which is a highly hydrophobic silica alumina silicate having a specific shape metal fiber and a high SiO ₂ / Al ₂ O ₃ molar ratio. It has been found that the above problems can be solved by using in combination.
That is, with respect to 100 parts by weight of resin component (C) containing 50 to 92% by weight of polyphenylene ether (A) and 50 to 8% by weight of styrene resin (B), 50 to 200 parts by weight of stainless microfiber (D), and The resin composition obtained by blending 0.1 to 5.0 parts by weight of the synthetic zeolite (E) represented by the following formula (1) is a resin kneaded and melt-kneaded without impairing the original properties of the modified polyphenylene ether resin. It is a conductive resin composition that can remarkably reduce the generation of odors during high-temperature heating such as molding processing and high-temperature heating of resin molded products, can be colored other than black, and has an extremely excellent appearance of molded products The present invention has been found and reached the present invention.

_{M 2 / n O · Al 2} O 3 · xSiO 2 · yH 2 O (1)
(Wherein, M represents a monovalent or divalent metal capable of ion exchange, n represents a valence of the metal, x represents a silica coefficient (a molar ratio of SiO ₂ / Al ₂ O ₃ ), 10 The number of ~ 500 is shown, y is the number of crystal water, and shows the number of 0-7.)

  The low odor conductive resin composition of the present invention maintains the original characteristics of the modified polyphenylene ether resin, is capable of being colored, and has a stable conductivity with little adhesion of dust and dust. It is suitable as a material for storage containers for electronic parts, trays for conveyance, and the like. In addition, the resin composition and molded products using the resin composition generate very little odor when heated at high temperatures, and can maintain a comfortable working environment even in a clean room with limited ventilation. It is extremely suitable for manufacturing molded articles such as trays for transporting electrical and electronic parts.

Hereinafter, the contents of the present invention will be described in detail. 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. In the present specification, a “group” such as an alkyl group may or may not have a substituent unless otherwise specified.
The polyphenylene ether (A) in the present invention is a polymer having an aromatic polyether structure, preferably the following formula (2)

（式中、Ｒ₁は炭素数１〜３の低級アルキル基、Ｒ₂およびＲ₃は、それぞれ、水素原子または炭素数１〜３の低級アルキル基を示す。）
で表される構造単位を主鎖に持つ重合体であって、ホモポリマーであってもコポリマーであってもよい。
Ｒ₁としては、メチル基、エチル基が好ましい。
Ｒ₂およびＲ₃が炭素数１〜３の低級アルキル基である場合、メチル基、エチル基が好ましい。

(In the formula, R ₁ represents a lower alkyl group having 1 to 3 carbon atoms, and R ₂ and R ₃ each represents a hydrogen atom or a lower alkyl group having 1 to 3 carbon atoms.)
A polymer having a structural unit represented by the following formula in its main chain, which may be a homopolymer or a copolymer.
R ₁ is preferably a methyl group or an ethyl group.
When R ₂ and R ₃ are lower alkyl groups having 1 to ₃ carbon atoms, a methyl group and an ethyl group are preferable.

  Examples of the polyphenylene ether (A) include poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, and poly (2,6-dipropyl- 1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, and other homopolymers Examples include copolymers such as 2,6-dialkylphenol / 2,3,6-trialkylphenol copolymer, especially poly (2,6-dimethyl-1,4-phenylene) ether, 2,6-dimethylphenol. A 2,3,6-trimethylphenol copolymer is preferred. Also suitable are polyphenylene ethers containing molecular constituents that improve properties such as molecular weight, melt viscosity and impact strength.

  The polyphenylene ether (A) used in the present invention preferably has an intrinsic viscosity at 30 ° C. measured in chloroform of 0.2 to 0.8 dl / g, preferably 0.3 to 0.6 dl / g. More preferred. When the intrinsic viscosity is 0.2 dl / g or more, the mechanical strength of the resin composition tends to be improved, and when it is 0.8 dl / g or less, the fluidity is improved and the molding process is easy. Tend to be.

  The styrene resin (B) used in the present invention is composed of a styrene monomer polymer, a copolymer of a styrene monomer and another copolymerizable monomer, and a styrene graft copolymer. Examples include coalescence.

Examples of the styrene monomer include styrene, α-methyl styrene, p-methyl styrene, and preferably styrene. Examples of the monomer copolymerizable with the styrenic monomer include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, methyl acrylate, ethyl acrylate, propyl acrylate, methyl methacrylate, and methacrylic acid. Examples include (meth) acrylic acid alkyl ester monomers such as ethyl, maleimide, N-phenylmaleimide, and the like, and preferred are vinyl cyanide monomer and (meth) acrylic acid alkyl ester monomer.
Examples of the copolymer of the styrene monomer and other copolymerizable monomer include a styrene / acrylonitrile resin (AS resin), and the styrene graft copolymer includes, for example, Examples include impact polystyrene (HIPS resin), acrylonitrile / butadiene / styrene resin (ABS resin), AES resin in which butadiene of the ABS resin is replaced with ethylene-propyne rubber, acrylonitrile / acrylate / styrene resin (AAS resin), and the like. . Examples of the method for producing the styrene-based copolymer include known methods such as an emulsion polymerization method, a solution polymerization method, a suspension polymerization method, and a bulk polymerization method.
As the styrenic resin (B), polystyrene and high-impact polystyrene are preferable in terms of compatibility with polyphenylene ether. Particularly when impact resistance is required, impact-resistant polystyrene is more preferable.

  The resin component (C) in the present invention contains 50 to 92% by weight of polyphenylene ether (A) and 50 to 8% by weight of styrene resin (B). Preferably, it contains 60 to 90% by weight of polyphenylene ether (A) and 40 to 10% by weight of styrene resin (B), more preferably 70 to 90% by weight of polyphenylene ether (A) and styrene resin (B ) 30 to 10% by weight. If the polyphenylene ether (A) is less than 50% by weight, the load deflection temperature and mechanical strength tend to decrease, and if it exceeds 92% by weight, the fluidity tends to decrease and the molding process tends to become complicated.

In order to improve impact strength, the resin component (C) in the present invention preferably further contains a styrene elastomer. The styrenic elastomer preferably blended in the present invention has a hard segment composed of a styrene polymer, and a soft segment composed of at least one polymer selected from the group consisting of polybutadiene, polyisoprene and hydrogenated products thereof. Block copolymers, specifically SBS (styrene / butadiene / styrene block copolymer), SIS (styrene / isoprene / styrene block copolymer), SEBS (styrene / ethylene / butylene / styrene block copolymer: hydrogenated SBS) Product), SEPS (styrene / ethylene / propylene / styrene block copolymer: hydrogenated product of SIS) and the like, and SEBS is particularly preferable.
The composition ratio of the hard segment and the soft segment of the styrenic elastomer can be appropriately selected within the range of 10:90 to 90:10 (molar ratio), preferably 10:90 to 50:50. The combination form of the soft segment blocks may be a diblock type or a triblock type.
The number average molecular weight of the styrenic elastomer is preferably 20,000 to 180,000, more preferably 30,000 to 160,000, still more preferably 35,000 to 140,000. By making the number average molecular weight 20,000 or more, the impact resistance and dimensional stability of the finally obtained resin composition are excellent, and further, the appearance of the molded product obtained from the resin composition is also made good. Can do. Further, it is preferable that the number average molecular weight is 180,000 or less because the fluidity of the finally obtained resin composition is improved and the molding process becomes easy.

The amount of the styrene-based elastomer is 1 to 25% by weight, preferably 3 to 20% by weight, and more preferably 5 to 15% by weight in the resin component (C). When the blending amount of the styrene elastomer is 1% by weight or more, the impact strength tends to be further improved. Moreover, when the compounding quantity of a styrene-type elastomer shall be 25 weight% or less, it exists in the tendency for the rigidity and load deflection temperature of a resin composition to improve, and it is preferable.
Furthermore, the resin component (C) used in the present invention may contain other resin components without departing from the spirit of the present invention. The compounding amount in this case is usually 50% by weight or less of the resin component (C).

In the present invention, the stainless microfiber (D) is blended mainly for the purpose of imparting conductivity to the resin composition. The type of stainless steel used as a raw material for the stainless microfiber (D) used in the present invention is not limited, but SUS304, SUS316, SUS403, and mixtures thereof are particularly preferable according to JIS regulations.
The average fiber length of the stainless microfiber (D) is preferably 50 to 500 μm, more preferably 100 to 300 μm. When the average fiber length is 50 μm or more, the conductive effect tends to be improved. When the average fiber length is 500 μm or less, poor dispersion due to entanglement between the fibers occurs, resulting in conductive variation and gate clogging during molding. The mechanical strength tends to be improved.
The average fiber diameter of the stainless microfiber (D) is preferably 1 to 50 μm, more preferably 10 to 30 μm, and particularly preferably 10 to 20 μm. When the average fiber diameter is 1 μm or more, the fibers are difficult to break, and when the average fiber diameter is 50 μm or less, the conductive effect is improved and the appearance tends to be improved. The average fiber length and average fiber diameter of the stainless microfibers in the present invention are obtained by dispersing the raw stainless steel microfibers on a slide glass, observing with a microscope and taking a photograph, and using the obtained photographs as image analysis software. It is the number average value of the values obtained by measuring the fiber length and the fiber diameter for 2000 stainless microfibers using (Imageron Pro Plus manufactured by Planetron).
The specific gravity of the stainless microfiber (D) is preferably 7.7 to 8.0.
The stainless microfiber (D) used in the present invention can be treated with a surface treatment agent such as a coupling agent used as a surface treatment agent for glass fibers.
The stainless microfiber (D) of the present invention has a good surface appearance and less drop-out than the conductive carbon black or the like conventionally used for imparting conductivity because it has less bleeding out to the surface of the molded product. In addition, since the volume ratio with respect to the blending amount is small, the dispersibility in the resin composition is also good, and there is no variation in electrical conductivity or unevenness of the molded product color, or mechanical strength is not lowered due to poor dispersion. In the present invention, the above performance can be exhibited more effectively by using a stainless microfiber (D) having a short average fiber length of about 100 to 300 μm.

  The compounding amount of the stainless microfiber (D) is 50 to 200 parts by weight, preferably 60 to 150 parts by weight, and more preferably 60 to 120 parts by weight with respect to 100 parts by weight of the resin component (C). By setting the blending amount to 50 parts by weight or more, the surface resistance value is greatly lowered and the conductive effect tends to be improved. Moreover, by setting it as 200 weight part or less, it exists in the tendency for specific gravity to fall and for mechanical strength to improve.

  In the present invention, synthetic zeolite is mainly used to reduce the odor derived from the residual production raw material, the odor due to the thermal decomposition of the resin, the odor due to the thermal decomposition or vaporization of the additive, etc. generated from the resin composition during high-temperature heating. (E) is blended. The synthetic zeolite (E) used in the present invention is generally an aluminosilicate having a three-dimensional framework structure and is represented by the following formula (1).

_{M 2 / n O · Al 2} O 3 · xSiO 2 · yH 2 O (1)
(Wherein, M represents a monovalent or divalent metal capable of ion exchange, n represents the valence of the metal, and x represents a silica coefficient (SiO ₂ / Al ₂ O ₃ molar ratio) of 10 to 10. 500 represents the number, y is the number of water of crystallization, and represents a number of 0 to 7.)

Zeolite includes natural zeolite and synthetic zeolite. Synthetic zeolite has a low silica coefficient (less than 10) hydrophilic zeolite (for example, A type zeolite, X type zeolite, Y type zeolite, etc.) and high silica coefficient. There are (more than 10) hydrophobic zeolites (for example, MFI type zeolite), but the above synthetic zeolite (E) used in the present invention is a hydrophobic zeolite and is easily available from the market. Among these, MFI type synthetic zeolite is preferable. The hydrophobic MFI-type synthetic zeolite has a three-dimensional network structure in which the pore entrance is formed by a 10-membered oxygen ring and is composed of linear pores and zigzag pores intersecting with them. For example, an ellipse having an effective pore diameter of 5 to 6 mm, a pore volume of 0.15 to 0.25 mL / g, and a specific surface area of 300 to 550 m ² / g is preferable. More preferably, the pore volume is 0.15 to 0.25 mL / g and the specific surface area is 300 to 450 m ² / g.

The synthetic zeolite (E) used in the present invention needs to be represented by the above formula (1), and the silica coefficient x is more preferably 20 to 60, and further preferably 30 to 60. . Further, M in the formula (1) is preferably sodium, potassium or calcium, and more preferably sodium. The value of y in formula (1) is preferably low.
Furthermore, the synthetic zeolite (E) used in the present invention has a water adsorption capacity of preferably less than 20% by weight, more preferably less than 15% by weight under the conditions of temperature 25 ° C./relative humidity 10% / normal pressure. More preferably, the synthetic zeolite is less than 10% by weight. In particular, a synthetic zeolite represented by the above formula (1) and having a silica coefficient x of 20 to 60 and a water adsorption capacity of less than 10% by weight under the conditions of temperature 25 ° C./relative humidity 10% / normal pressure is The molded product obtained from such a low odor resin composition containing a synthetic zeolite has the characteristics that it does not generate silver and has a very good appearance.
The average primary particle diameter of the synthetic zeolite (E) according to the present invention is preferably 0.1 to 20 μm, more preferably 0.2 to 10 μm, and further preferably 0.5 to 5 μm. By setting the average primary particle size of the synthetic zeolite (E) to 0.1 μm or more, the melt viscosity of the resin composition tends to be low, and by setting the average particle size to 20 μm or more, the rough surface of the molded product becomes less noticeable, and the appearance Tends to be improved.

  The compounding quantity of a synthetic zeolite (E) is 0.1-5.0 weight part with respect to 100 weight part of resin components (C), Preferably it is 0.2-3.0 weight part. If the blending amount is less than 0.1 parts by weight, the effect of reducing odor is small, and even if blended exceeding 5.0 parts by weight, no further odor reducing effect can be expected, and the mechanical strength also decreases. There is.

  In addition to the above components, the low-odor conductive resin composition of the present invention includes, if necessary, colorants such as pigments and dyes, aliphatic carboxylic acids, aliphatic carboxylic acid esters, polyolefin waxes, and silicone oils. Mold release agents such as, hindered phenol compounds, phosphorus compounds and stabilizers such as zinc oxide, flame retardants such as phosphate esters and condensed phosphate esters, hindered amines, benzotriazoles, benzophenones, epoxies, etc. Additives such as UV absorbers, antioxidants, lubricants, plasticizers, antistatic agents, slidability improvers, compatibilizers, difluoroethylene polymers, tetrafluoroethylene polymers, tetrafluoroethylene-hexafluoropropylene Polymer, copolymer of tetrafluoroethylene and fluorine-free ethylene monomer, etc. Reinforcing fillers such as fluororesins, glass fibers, glass flakes, carbon fibers, and stainless microfibers, or whiskers such as potassium titanate, aluminum borate, and calcium silicate, mica, talc Inorganic fillers such as clay can be blended. The blending method of these additives can be appropriately carried out by a conventionally known method that makes use of these characteristics.

In the present invention, a colorant (F) can be added. In conventional conductive resin compositions, carbon black has been employed to impart conductivity, and in many cases, only a black resin composition can be obtained. However, in the present invention, since conductivity can be imparted without using conductive carbon black, it can be colored freely.
Examples of the colorant (F) in the present invention include dyes, inorganic pigments, and organic pigments that are generally used for thermoplastic resins.
Examples of the dye include azo dyes, anthraquinone dyes, phthalocyanine dyes, indigo dyes, diphenylmethane dyes, acridine dyes, cyanine dyes, nitro dyes, and nigrosine. Inorganic pigments include oxide pigments such as titanium oxide, red pepper and cobalt blue, hydroxide pigments such as alumina white, sulfide pigments such as zinc sulfide and cadmium yellow, silicate pigments such as white carbon and talc, and carbon black. Etc. Examples of organic pigments include nitro pigments, azo pigments, phthalocyanine pigments, and condensed polycyclic pigments. Among these, an inorganic pigment is preferable because it is difficult to bleed out to the surface of the molded product. The colorant may also be used as a masterbatch with a thermoplastic resin such as polyphenylene ether resin, polystyrene resin, polycarbonate resin, or acrylic resin for the purpose of improving handling at the time of extrusion.

  0.01-20 weight part is preferable with respect to 100 weight part of resin components (C), and, as for the compounding quantity of a coloring agent (F), 0.1-15 weight part is more preferable. In addition, inorganic pigments such as titanium oxide may be used for purposes other than coloring (for example, imparting light-shielding properties). In this case, the blending amount is usually 5 to 100 parts by weight of the resin component (C). 20 parts by weight, preferably 5 to 15 parts by weight. Two or more of these colorants may be used in combination.

Examples of the stabilizer in the present invention include hindered phenol compounds, phosphorus compounds, and zinc oxide.
Specific examples of the hindered phenol compound include n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,6-hexanediol-bis [3- (3,5 -Di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,6-di-tert-butyl- 4-methylphenol, 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8, 10-tetraoxaspiro [5,5] undecane, triethylene glycol-bis [3- (3-tert-butyl-5-methyl) 4-hydroxyphenyl) propionate], 3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3,5-di-) -Tert-butyl-4-hydroxybenzyl) benzene, 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], tris- (3,5-di -Tert-butyl-4-hydroxybenzyl) -isocyanurate, N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide) and the like. Among these, n-octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,6-hexanediol-bis [3- (3,5-tert-butyl-4 -Hydroxyphenyl) propionate], 2,6-di-tert-butyl-4-methylphenol, 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-) 5-methylphenyl) propionyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane is preferred.

As the phosphorus compound, for example, a phosphonite compound or a phosphite compound is preferably used.
Examples of the phosphonite compound include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,5-di-tert-butylphenyl) -4,4′-. Biphenylene diphosphonite, tetrakis (2,3,4-trimethylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,3-dimethyl-5-ethylphenyl) -4,4'-biphenylene diphosphonite Tetrakis (2,6-di-tert-butyl-5-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3,4-tributylphenyl) -4,4'-biphenylenediphosphonite Tetrakis (2,4,6-tri-tert-butylphenyl) -4,4′-biphenylenediphosphonite and the like. Among them, tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite is preferable.
Examples of the phosphite compound include tris (2,4-di-tert-butylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and bis (2,6-diphenyl). -Tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, 4,4'-butylidenebis (3-methyl-6- tert-butylphenylditridecyl) phosphite, 1,1,3-tris (2-methyl-4-ditridecylphosphite-5-tert-butyl-phenyl) butane, tris (nonylphenyl) phosphite, 4,4 '-Isopropylidenebis (phenyldialkylphosphite) and the like 2,4-di-tert-butylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (2,6-di-tert-butyl-4-methyl) Phenyl) pentaerythritol diphosphite is preferred.

As zinc oxide, for example, those having an average particle diameter of 0.02 to 1 μm are preferable, and those having an average particle diameter of 0.08 to 0.8 μm are more preferable.
Among these stabilizers, zinc oxide is preferable because it does not easily generate mold deposits and hardly changes color.

  The amount of the stabilizer is preferably 0.01 to 5 parts by weight, more preferably 0.05 to 3 parts by weight with respect to 100 parts by weight of the resin component (C). By making the blending amount 0.01 parts by weight or more, the effect as a stabilizer can be sufficiently exerted, and by making it 5 parts by weight or less, a decrease in mechanical strength and generation of mold debossed during molding are suppressed. can do. Two or more of these stabilizers may be used in combination.

Examples of the release agent in the present invention include aliphatic carboxylic acids, aliphatic carboxylic acid esters, polyolefin waxes, and silicone oils.
Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monocarboxylic acid, dicarboxylic acid, and tricarboxylic acid. Here, the aliphatic carboxylic acid also includes an alicyclic carboxylic acid. Of these, preferred aliphatic carboxylic acids are mono- or dicarboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monocarboxylic acids having 6 to 36 carbon atoms are more preferred. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, valeric acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, melissic acid, tetratriacontanoic acid. , Montanic acid, glutaric acid, adipic acid, azelaic acid and the like.

  As the aliphatic carboxylic acid component constituting the aliphatic carboxylic acid ester, the same aliphatic carboxylic acid as that described above can be used. On the other hand, examples of the alcohol component constituting the aliphatic carboxylic acid ester include saturated or unsaturated monohydric alcohols and saturated or unsaturated polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Of these alcohols, monovalent or polyvalent saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the aliphatic alcohol also includes an alicyclic alcohol.

  Specific examples of these alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol. Etc. can be mentioned. These aliphatic carboxylic acid esters may contain an aliphatic carboxylic acid and / or alcohol as impurities, and may be a mixture of a plurality of compounds.

  Specific examples of the aliphatic carboxylic acid ester include beeswax (mixture based on myristyl palmitate), stearyl stearate, behenyl behenate, octyldodecyl behenate, glycerin monopalmitate, glycerin monostearate, glycerin diester Mention may be made of stearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monosterate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate.

  Examples of polyolefin waxes include olefin homopolymers and copolymers. Examples of the olefin homopolymer include polyethylene wax, polypropylene wax and the like, partial oxides thereof, and mixtures thereof. Examples of the olefin copolymer include ethylene, propylene, 1-butene, 1-hexene, 1-decene, 2-methylbutene-1, 3-methylbutene-1,3-methylpentene-1, 4-methylpentene-1, and the like. Copolymers such as α-olefins, monomers copolymerizable with these olefins, for example, unsaturated carboxylic acids or their anhydrides [maleic anhydride, (meth) acrylic acid, etc.], (meth) acrylic acid esters And copolymers with polymerizable monomers such as [methyl (meth) acrylate, alkyl ester having 1 to 6 carbon atoms of (meth) acrylic acid such as ethyl (meth) acrylate] and the like. In addition, these copolymers include random copolymers, block copolymers, or graft copolymers. The olefin copolymer is usually a copolymer of ethylene and at least one monomer selected from other olefins and polymerizable monomers. Of these polyolefin waxes, polyethylene wax is most preferred. The polyolefin wax may have a linear or branched structure.

  Examples of silicone oils include those composed of polydimethylsiloxane, and some or all of the methyl groups of polydimethylsiloxane are substituted with phenyl groups, hydrogen atoms, alkyl groups having 2 or more carbon atoms, halogenated phenyl groups, and fluoroester groups. Silicone oil, epoxy-modified silicone oil having an epoxy group, amino-modified silicone oil having an amino group, alcohol-modified silicone oil having an alcoholic hydroxyl group, polyether-modified silicone oil having a polyether structure, and the like. You may use together.

  The compounding amount of the release agent is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 6 parts by weight, and still more preferably 0.1 to 3 parts by weight with respect to 100 parts by weight of the resin component (C). . When the blending amount is 0.01 parts by weight or more, the release effect is more easily exhibited, and by 10 parts by weight or less, problems such as heat resistance, mold contamination, and poor plasticization are less likely to occur.

  The method for obtaining the conductive resin composition of the present invention includes, for example, (1) various kneaders such as uniaxial and multiaxial kneaders, Banbury mixers, rolls, Brabender plastograms, etc. (2) The above components and some of the additives added as necessary are kneaded in advance, and then kneaded together with other components. Method (including a method using a masterbatch), (3) an additive to be added as necessary is dissolved in a suitable solvent, for example, hydrocarbons such as hexane, heptane, benzene, toluene, xylene and derivatives thereof. Or a solution mixing method of mixing with the resin component (C) in a suspended state. The melt kneading method (1) or (2) is preferable from the industrial cost, but is not limited thereto. In the melt-kneading, it is preferable to use a uniaxial or biaxial extruder.

As a method for molding a molded product molded using the conductive resin composition of the present invention, for example, a container for storage of electric and electronic parts or a tray for conveyance, an injection molding method is often used because of good productivity. However, it is not particularly limited, and molding methods generally used for thermoplastic resins, for example, molding methods such as hollow molding, extrusion molding, thermoforming from a sheet-like molded product, and rotational molding can be applied.
Examples of molded products formed using the conductive resin composition of the present invention include IC and CCD trays, cases, housings for electric and electronic parts such as housings, and housings, and trays for transport. The conductive resin composition of the present invention is suitable for IC and CCD trays used at high temperatures.

The Charpy impact strength of the resin composition of the present invention is preferably ²⁰ kJ / m ² or more when measured by the method described below. Moreover, when the load deflection temperature of the resin composition of this invention is measured by the method mentioned later, it is preferable that it is 155 degreeC or more.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded. The resin compositions and molded articles in the examples and comparative examples were evaluated as follows.

(1) Odor A: During melt kneading of the resin composition carried out under the production conditions described later, at the location 50 cm away from the die of the twin screw extruder (screw diameter 30 mm), five people sniff the odor and The evaluation score was given by the standard, and the total score of all members was taken as the evaluation score.
Odor B: An ISO test piece for Charpy impact test obtained under the molding conditions described below is placed in a 300 ml stoppered Erlenmeyer flask and heated at 140 ° C. for 3 hours. The total score of all members was used as the evaluation score.
Evaluation points Evaluation criteria
1 point Very faint smell
2 point Smell
3 points
4 points Strong smell
5 points Very strong odor

(2) Gate occlusion: Using a mold having a gate having a gate diameter of 0.7 mm and a gate land of 2.0 mm in the center of a disk having a thickness of 1.0 mm and a diameter of 50 mm, a cylinder set temperature of 290 to 330 ° C., 500 shots of continuous injection molding were performed under conditions of a mold temperature of 120 ° C. and a molding cycle of 30 seconds, and the number of shots at which gate clogging occurred was examined. Those in which no clogging occurred even after 500 shots are displayed as “> 500” in Table 1.

(3) Appearance of molded product: Visually observed the occurrence of silver, flow marks, etc. in a square plate molded product of 50 mm × 90 mm × 3.2 mmt obtained under the molding conditions described later, and in order from the molded product with excellent appearance. The evaluation was made in three stages, as follows: ○, Δ, and ×.
○: No appearance defects such as silver and flow mark.
Δ: Some appearance defects such as silver and flow mark are seen.
X: Appearance defects such as silver and flow mark are conspicuous.

(4) Charpy impact strength: Using the ISO test pieces for Charpy impact test obtained under the molding conditions described later, 5 pieces were measured at 23 ° C. according to the ISO 527 standard, and the Charpy impact strength (hereinafter referred to as “5” average value) was measured. Impact strength and abbreviation).

(5) Load deflection temperature: The load deflection temperature (hereinafter abbreviated as DTUL) was measured under the condition of 1.82 MPa according to the ISO75 standard using the ISO test piece for load deflection temperature test obtained under the molding conditions described later. .

(6) Surface resistivity: 50 mm × 90 mm × 3.2 mmt square plate product obtained under the molding conditions described later was used, and measurement was performed at any three locations using Loresta or Hiresta of Mitsubishi Chemical Corporation products. It was. For those having a surface resistivity of 10 ⁴ Ω or more, Hiresta was used, and for those having a surface resistivity of 10 ⁴ Ω or less, Loresta was used.

(7) Tape peelability: A square plate molded product of 50 mm × 90 mm × 3.2 mmt obtained under the molding conditions described later is used. 18 "was affixed and the peeled state of the surface of the molded product when it was peeled off was visually observed and evaluated in the following three grades: ○, Δ, and ×. It can be judged that the smaller the peeling, the less the stainless microfiber or carbon black peels off.
◯: Even when the tape is applied and rubbed with force, the surface of the molded product is not peeled at all.
[Delta]: When the cellophane tape is applied and rubbed with force, the surface of the molded product is peeled off.
X: Peeling occurs on the surface of the molded article even if a cellophane tape is applied and lightly rubbed.

[raw materials]
The following raw materials were prepared.
(1) Poly (2,6-dimethyl-1,4-phenylene) ether resin: manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name “PX100F”, intrinsic viscosity 0.38 dl / g (measured in chloroform at 30 ° C.) (Hereafter abbreviated as “PPE”)
(2) Styrenic resin: high impact polystyrene: manufactured by Toyo Styrol Co., Ltd., trade name “H485”, weight average molecular weight 200,000, MFR 3.2 g / 10 min (hereinafter abbreviated as “HIPS”)

(3-1) Stainless steel microfiber: manufactured by JFE Techno Research Co., Ltd., trade name “SMF-708AE”, average fiber length 150 μm, average fiber diameter 15 μm, specific gravity 7.9 (hereinafter abbreviated as “SMF”)
(3-2) (for comparative example) Stainless steel fiber: Stainless steel fiber master pellet, manufactured by Toyo Ink Mfg. Co., Ltd., trade name “Rioconduct”, 8 μm diameter stainless steel fiber converged with polyester and cut to a pellet length of 4 mm And 75% by weight of stainless fiber (hereinafter abbreviated as “SUS”)
(3-3) Carbon black: Ketjen Black International Co., Ltd., trade name “Ketjen Black EC”, average particle size of 30 μm (hereinafter abbreviated as “CB”)

(4-1) MFI type synthetic high silica zeolite: Mizusawa Chemical Industry Co., Ltd., trade name “Mizuka Sieves EX-122”, M in the above formula (1) is sodium, n is 1, silica coefficient x = 33, and the number of water of crystallization y = 0-7. Also, it has an elliptical shape with an effective pore diameter of 5 to 6 mm, a pore volume of 0.15 to 0.25 mL / g, a specific surface area of 300 to 450 m ² / g, an average primary particle diameter of 2.0 μm, a temperature of 25 ° C./relative humidity. Moisture adsorption capacity under the condition of 10% / normal pressure is 7% by weight (hereinafter abbreviated as “M zeolite”)
(4-2) (For Comparative Example) X-type zeolite: manufactured by Nippon Chemical Industry Co., Ltd., trade name “Zeostar NX-110P”, silica coefficient x = 2.6, effective pore size 9 mm, average primary particle size 3 μm Water adsorption capacity under the conditions of temperature 25 ° C./relative humidity 10% / normal pressure 25% by weight (hereinafter abbreviated as “X zeolite”)

(5) Release agent: polyethylene wax, manufactured by Sanyo Chemical Industries, trade name “Sunwax 151P”, density 0.93 g / ml, weight average molecular weight 2,000 (hereinafter abbreviated as “release agent”)
(6) Stabilizer: Zinc oxide (reagent grade 1), manufactured by Honjo Chemical Co. (hereinafter abbreviated as “stabilizer”)
(7) Colorant: Red inorganic pigment, manufactured by Toda Kogyo Co., Ltd., trade name “140ED”

[Method for Producing Resin Composition]
A composition prepared by adjusting the above-mentioned raw materials with the blending ratio shown in Table 1 was prepared by using Tanabe Plastics Machine Co., Ltd.'s "VS-40" (single screw extruder with a screw diameter of 40 mm) and a cylinder set temperature. It melted and kneaded under conditions of 270 to 320 ° C. and a screw rotation speed of 50 rpm, and extruded to produce a pellet-shaped conductive resin composition.
[Method for producing test specimen for evaluation]
The pellet-shaped conductive resin composition obtained by the above method was dried for 4 hours using a hot air dryer having a temperature of 110 ° C., and then a cylinder set temperature of 300 using an IS150 type injection molding machine manufactured by Toshiba Machine Co., Ltd. ~ 330 ° C, mold temperature is 100-120 ° C depending on the composition when molding the molded product appearance and surface resistivity evaluation, 140 ° C when molding the tape peelability evaluation Then, a square plate molded product of 50 mm × 90 mm × 3.2 mmt for evaluation of molded product appearance, surface resistivity and tape peelability was injection molded. An ISO test piece for Charpy impact test and load deflection temperature test was molded under the same temperature conditions as the above-mentioned square plate molded product was injection molded using a J50 type injection molding machine manufactured by Nippon Steel Works.

[Examples 1 to 3, Comparative Examples 1 to 4]
The evaluation results obtained by the above method are shown in Table 1 below.
The resin compositions of Examples 1 to 3 of the present invention were low in odor, did not clog the gate during injection molding, and were excellent in appearance of molded product, impact strength, DTUL, surface resistivity, and tape peelability. On the other hand, the resin composition of Comparative Example 1 in which no zeolite was used was extremely strong in odor and inferior in impact strength. Further, the resin composition of Comparative Example 2 having the same composition as that of Example 1 except that X zeolite used in known literatures has a slight odor, the appearance of the molded product is poor, impact strength and tape The peelability was also poor. In addition, the resin composition of Comparative Example 3 having the same composition as Example 2 except that stainless steel master pellets were used instead of stainless microfibers (D) was slightly inferior in odor and from the start of molding. At the 135th shot, the gate was closed and molding was impossible, and further, the appearance of the molded product and the tape peelability were lowered, and the impact strength was greatly inferior. Instead of the stainless steel microfiber (D), the resin composition of Comparative Example 4 using carbon black had a little odor, the molded product appearance and DTUL were lowered, and the impact strength and tape peelability were greatly inferior.

Claims (11)

For 100 parts by weight of resin component (C) containing 50 to 92% by weight of polyphenylene ether (A) and 50 to 8% by weight of styrene resin (B), 50 to 200 parts by weight of stainless microfiber (D) and the following formula A conductive resin composition comprising 0.1 to 5.0 parts by weight of the synthetic zeolite (E) represented by (1).
_{M 2 / n O · Al 2} O 3 · xSiO 2 · yH 2 O (1)
(Wherein, M represents a monovalent or divalent metal capable of ion exchange, n represents the valence of the metal, and x represents a silica coefficient (SiO ₂ / Al ₂ O ₃ molar ratio) of 10 to 10. 500 represents the number, y is the number of water of crystallization, and represents a number of 0 to 7.) The conductive resin composition according to claim 1, wherein the polyphenylene ether (A) is a polymer having a structural unit represented by the following formula (2) in the main chain.

(In the formula, R ₁ represents a lower alkyl group having 1 to 3 carbon atoms, and R ₂ and R ₃ each represents a hydrogen atom or a lower alkyl group having 1 to 3 carbon atoms.) The conductive resin composition according to claim 1 or 2, wherein the styrenic resin (B) is polystyrene or high-impact polystyrene. The conductive resin composition according to any one of claims 1 to 3, wherein the resin component (C) includes 60 to 90% by weight of polyphenylene ether (A) and 40 to 10% by weight of a styrene resin (B). object. M in said Formula (1) is sodium, The conductive resin composition of any one of Claims 1-4. The conductive resin composition according to any one of claims 1 to 5, wherein the silica coefficient x in the formula (1) is 20 to 60, and the number y of crystal water is 0 to 7. The conductive resin composition according to any one of claims 1 to 6, wherein the synthetic zeolite (E) is MFI type zeolite. The conductive resin composition according to claim 1, wherein the stainless microfiber (D) has an average fiber length of 50 to 500 μm and an average fiber diameter of 1 to 50 μm. Furthermore, 0.01-20 weight part of coloring agents (F) are mix | blended with respect to 100 weight part of said resin components (C), The conductive resin composition of any one of Claims 1-8. . The molded article formed by shape | molding the conductive resin composition of any one of Claims 1-9. The molded article according to claim 10, wherein the molded article is a tray for transporting electrical and electronic parts.