JP2006257174A - Resin composition and optical molded article comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition having good moldability at processing, excellent heat conductivity, excellent dimensional stability at heated time, and excellent slidability, and further having excellent rigidity change and cracking resistance in a cold and hot cycle test assuming actual using condition; and to provide an optical molded article such as an optical pick-up part, comprising the resin composition. <P>SOLUTION: The resin composition comprises (A) 100 pts.wt. thermoplastic resin, (B) 20-300 pts.wt. expandable graphite and (C) 20-300 pts.wt. graphite except the exfoliated graphite regulated so that the compounded ratio (B)/(C) of the exfoliated graphite (B) to the graphite (C) except the exfoliated graphite may be (1/9)-(5/5). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention has good moldability during processing, excellent thermal conductivity, excellent dimensional stability at elevated temperature, and slidability, and changes in rigidity and split resistance when exposed to a cold cycle under actual use conditions. It is related with the resin composition excellent in the above, and the molded article for optics consisting thereof.

  In recent years, recording devices such as CDs and DVDs that write and read information using laser light have become widespread, but various components used in them, especially laser oscillators, lenses for narrowing laser beams, and laser beam The base (optical pickup slide base, optical pickup body) equipped with a rising mirror to change the direction, a beam splitter, a laser light receiving sensor, etc., is distorted due to changes in the operating environment temperature. It will shift | deviate and an error will arise in writing and reading of information.

  As the recording density increases, the allowable range of deviation of the laser optical axis is becoming smaller, and the temperature rises due to heat storage due to higher performance and smaller size of the recording device. However, there is a need for a material with excellent heat dissipation that is less prone to optical axis deviation and can suppress a decrease in laser life due to temperature rise.

For example, as a method of improving optical axis stability, graphite having a particle size of 20 to 900 μm is blended with polyarylene sulfide resin to stabilize the temperature change of the laser optical axis (see Patent Document 1), and tension is applied to polyarylene sulfide resin. A method of blending reinforcing agents and fillers such as pitch-based carbon fiber having an elastic modulus of 500 GPa or more, graphite and calcium carbonate, and stabilizing the temperature change of the laser optical axis (see Patent Document 2), copper in polyarylene sulfide resin A method of blending inorganic fillers, fibrous fillers such as glass fibers, and non-fibrous fillers such as calcium carbonate at a specific ratio to stabilize the temperature change of the laser optical axis (see Patent Document 3), polyarylene sulfide resin A filler such as flaky graphite and zinc oxide whisker is added to a thermoplastic resin, etc., or a phosphate ester in a specific ratio As a method of stabilizing the laser optical axis by tableting (see Patent Document 4) and a method of improving heat dissipation, an inorganic filler such as graphite and glass fiber having an average particle diameter of 1 to 300 μm is added to a polyarylene sulfide resin. A method of blending at a specific ratio (see Patent Document 5) has been proposed. However, the methods described in Patent Documents 1 to 5 describe the improvement of heat dissipation, the improvement of optical axis stability, etc. by making graphite highly filled and controlling the particle size of graphite used. However, when subjected to a cold cycle, the rigidity changed and cracked, which was not satisfactory in practice. In addition, the method described in Patent Document 6 describes that the conductivity is improved by using expanded graphite and graphite in combination. However, in the method specifically described in the same document, the thermal cycle property is particularly high. It was still not satisfactory.
JP-A-2004-339290 (first and second items, examples) Japanese Patent Application Laid-Open No. 2002-129015 (first and second items, examples) Japanese Patent Laid-Open No. 2003-327828 (first and second items, examples) Japanese Patent Application Laid-Open No. 2004-176062 (first and second items, examples) Japanese Patent Application Laid-Open No. 2003-231811 (first and second items, examples) Japanese Unexamined Patent Publication No. 2000-0117179 (first and second items, examples)

  The present invention solves the above-mentioned conventional problems and is excellent in thermal conductivity, dimensional stability at elevated temperature, and slidability while maintaining the product design freedom and productivity that are the characteristics of thermoplastic resins. An object of the present invention is to provide a resin composition excellent in change in rigidity and split resistance when exposed to a thermal cycle under actual use conditions, and an optical pickup component comprising the same.

  As a result of intensive studies to solve the above problems, the present inventors have reached the present invention.

That is, the present invention
(1) (B) containing 20 to 300 parts by weight of expanded graphite and (C) 20 to 300 parts by weight of graphite other than expanded graphite with respect to 100 parts by weight of (A) thermoplastic resin, and (B (B) / (C) = 1/9 to 5/5. The resin composition is characterized in that the blending ratio of expanded graphite and graphite other than (C) expanded graphite is (B) / (C) = 1/9 to 5/5.
(2) The resin composition according to (1), further comprising (D) 5 to 300 parts by weight of other inorganic fillers per 100 parts by weight of the thermoplastic resin (A).
(3) The resin described in (1) or (2), wherein the thermoplastic resin (A) is at least one selected from polyamide resin, non-liquid crystalline polyester resin, liquid crystal polymer, and polyarylene sulfide resin. Composition.
(4) An optical molded product obtained by injection molding or injection press molding the resin composition according to any one of (1) to (3).
(5) The optical molded product according to (4), wherein the optical molded product is used for an optical pickup component.

  The resin composition of the present invention has good workability and thermal conductivity, dimensional stability at elevated temperature, which could not be obtained with conventional materials by blending expanded graphite and graphite other than expanded graphite in a specific ratio, It is excellent in slidability and can be imparted with a change in rigidity and split resistance even when subjected to a thermal cycle under actual use conditions, and is particularly useful for optical molded articles. And it has excellent environmental stability of the laser focus used for CD (compact disc), DVD (digital versatile disc), laser disc, magneto-optical disc, etc., and excellent characteristics under actual use environment such as heat dissipation characteristics and cooling cycle. It is possible to provide an optical molded product such as an optical pickup component that exhibits the above.

  Hereinafter, the present invention will be described in detail. In the present invention, “weight” means “mass”.

  In the present invention, the thermoplastic resin (A) is a synthetic resin that can be melt-molded.

  Specific examples thereof include, for example, non-liquid crystalline polyester resins such as non-liquid crystalline semi-aromatic polyester and non-liquid crystalline wholly aromatic polyester, liquid crystal polymers (liquid crystalline polyester resin, liquid crystalline polyester amide resin, etc.), polycarbonate, fat Polyamide resins such as aromatic polyamide, aliphatic-aromatic polyamide, wholly aromatic polyamide, polyoxymethylene, polyimide, polyamide, polybenzimidazole, polyketone, polyetheretherketone, polyetherketone, polyethersulfone, polyetherimide, Olefin polymers such as modified polyphenylene ether, polysulfone, phenoxy resin, polyarylene sulfide resin, polypropylene, polyethylene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, Tylene / propylene / non-conjugated diene copolymer, ethylene / ethyl acrylate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer and ethylene / propylene-g-maleic anhydride One or more selected from olefin copolymers such as copolymers, ABS resins, AS resins, styrene copolymers such as polystyrene, methacrylic resins, polyester ether elastomers, polyester elastomers, polyamide elastomers, and other elastomers (“/” Represents copolymerization, the same applies hereinafter).

  Among the above-mentioned thermoplastic resins, liquid crystal polymers such as non-liquid crystalline polyester resin, polyamide resin, liquid crystalline polyester resin, polycarbonate, polyarylene sulfide resin, polyethylene, polypropylene, polystyrene, ABS, in terms of mechanical properties and moldability One or a mixture of two or more selected from a modified polyphenylene ether and a phenoxy resin is preferably used, among which a liquid crystal polymer such as a polyamide resin, a non-liquid crystalline polyester resin, a liquid crystalline polyester resin, or a polyarylene sulfide resin is preferably used. In particular, liquid crystal polymers and polyarylene sulfide resins are preferably used.

  Further, representative examples of polyarylene sulfide resins include polyphenylene sulfide (hereinafter sometimes abbreviated as PPS), polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers thereof, block copolymers, and mixtures thereof. Among them, polyphenylene sulfide is particularly preferably used. Such polyphenylene sulfide is a polymer containing a repeating unit represented by the following structural formula, preferably 70 mol% or more, more preferably 90 mol% or more. When the repeating unit is 70 mol% or more, the heat resistance is high. It is preferable at an excellent point.

  In addition, the polyphenylene sulfide resin can be composed of 30 mol% or less of the repeating unit with a repeating unit having the following structural formula, and may be a random copolymer or a block copolymer. Or a mixture thereof.

  Such polyarylene sulfide resins are generally known in the art, that is, a method for obtaining a polymer having a relatively small molecular weight described in JP-B-45-3368, or JP-B-52-12240 and JP-A-61-7332. It can be produced by a method for obtaining a polymer having a relatively large molecular weight described in the publication.

  In the present invention, the polyarylene sulfide resin obtained as described above is subjected to crosslinking / polymerization by heating in air, heat treatment under an inert gas atmosphere such as nitrogen or under reduced pressure, an organic solvent, hot water, Of course, it is possible to use it after various treatments such as washing with an acid aqueous solution, activation with a functional group-containing compound such as an acid anhydride, amine, isocyanate, or a functional group-containing disulfide compound.

  Specific methods for crosslinking / high molecular weight polyarylene sulfide resin by heating include an atmosphere of an oxidizing gas such as air or oxygen, or a mixed gas atmosphere of the oxidizing gas and an inert gas such as nitrogen or argon. Below, a method of heating until a desired melt viscosity is obtained at a predetermined temperature in a heating container can be exemplified. In this case, the heat treatment temperature is preferably 150 to 280 ° C., more preferably 200 to 270 ° C., and the treatment time is preferably 0.5 to 100 hours, more preferably 2 A range of ˜50 hours is selected, but by controlling both, a target viscosity level can be obtained. Such a heat treatment apparatus may be a normal hot air dryer or a heating apparatus with a rotary or stirring blade. However, in the case of efficient and more uniform treatment, a heating apparatus with a rotary or stirring blade is used. Is more preferable.

As a specific method for heat-treating the polyarylene sulfide resin under an inert gas atmosphere such as nitrogen or under reduced pressure, an inert gas atmosphere such as nitrogen or under reduced pressure (preferably 7,000 Nm ^-2 or less), Examples of the heat treatment method include a heat treatment temperature of 150 to 280 ° C, preferably 200 to 270 ° C, and a heating time of 0.5 to 100 hours, preferably 2 to 50 hours. Such a heat treatment apparatus may be a normal hot air dryer or a heating apparatus with a rotary or stirring blade. However, in the case of efficient and more uniform treatment, a heating apparatus with a rotary or stirring blade is used. Is more preferable.

  When the polyarylene sulfide resin is washed with an organic solvent, the organic solvent used for washing is not particularly limited as long as it does not have an action of decomposing the polyarylene sulfide resin. For example, nitrogen-containing polar solvents such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, sulfoxide sulfone solvents such as dimethyl sulfoxide, dimethylsulfone, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, acetophenone, dimethyl ether, dipropyl ether , Ether solvents such as tetrahydrofuran, halogen solvents such as chloroform, methylene chloride, trichloroethylene, ethylene chloride, dichloroethane, tetrachloroethane, chlorobenzene, methanol, ethanol, propanol, butanol, pentanol, ethylene glycol, propylene glycol, phenol, Alcohol / phenolic solvents such as cresol and polyethylene glycol, benzene and toluene Ene, and aromatic hydrocarbon solvents such as xylene may be used. Of these organic solvents, N-methylpyrrolidone, acetone, dimethylformamide, chloroform and the like are particularly preferably used. These organic solvents are used alone or in combination of two or more.

  As a specific method of washing with such an organic solvent, there is a method of immersing a polyarylene sulfide resin in an organic solvent, and it is possible to appropriately stir or heat as necessary. There is no restriction | limiting in particular about the washing | cleaning temperature at the time of wash | cleaning polyarylene sulfide resin with an organic solvent, Arbitrary temperature of about normal temperature-about 300 degreeC can be selected. Although the cleaning efficiency tends to increase as the cleaning temperature increases, a sufficient effect is usually obtained at a cleaning temperature of room temperature to 150 ° C. The polyarylene sulfide resin that has been washed with an organic solvent is preferably washed several times with water or warm water in order to remove the remaining organic solvent. The water washing temperature is preferably 50 to 90 ° C, and preferably 60 to 80 ° C.

  The following method can be illustrated as a specific method when the polyarylene sulfide resin is treated with hot water. That is, the water used is preferably distilled water or deionized water in order to exhibit a preferable chemical modification effect of the polyarylene sulfide resin by hot water washing. The operation of the hot water treatment is usually performed by adding a predetermined amount of polyarylene sulfide resin to a predetermined amount of water, and heating and stirring at normal pressure or in a pressure vessel. The ratio of the polyarylene sulfide resin and water is preferably as much as possible, and is preferably used at a bath ratio of 200 g or less of polyarylene sulfide resin with respect to 1 liter of water.

  The following method can be illustrated as a specific method in the case of acid-treating a polyarylene sulfide resin. That is, there is a method of immersing a polyarylene sulfide resin in an acid or an aqueous solution of an acid, and stirring or heating can be appropriately performed as necessary. The acid used is not particularly limited as long as it does not have the action of decomposing the polyarylene sulfide resin, such as aliphatic saturated monocarboxylic acids such as formic acid, acetic acid, propionic acid and butyric acid, chloroacetic acid and dichloroacetic acid. Halo-substituted aliphatic saturated carboxylic acids, aliphatic unsaturated monocarboxylic acids such as acrylic acid and crotonic acid, aromatic carboxylic acids such as benzoic acid and salicylic acid, oxalic acid, malonic acid, succinic acid, phthalic acid, fumaric acid, etc. Dicarboxylic acid and inorganic acidic compounds such as sulfuric acid, phosphoric acid, hydrochloric acid, carbonic acid and silicic acid are used. Of these acids, acetic acid and hydrochloric acid are particularly preferably used. The polyarylene sulfide resin subjected to the acid treatment is preferably washed several times with water in order to remove the remaining acid or salt. The water washing temperature is preferably 50 to 90 ° C, and preferably 60 to 80 ° C. The water used for washing is preferably distilled water or deionized water in the sense that the effect of the preferred chemical modification of the polyarylene sulfide resin by acid treatment is not impaired.

  The weight average molecular weight of the polyarylene sulfide resin used in the present invention is preferably 50000 or less, more preferably 40000 or less, and more preferably 25000 or less in terms of polystyrene to enable high filler filling. It is particularly preferred. Although there is no restriction | limiting in particular about the minimum of a weight average molecular weight, When considering residence stability etc., it is preferable that it is 1500 or more.

  Here, the weight average molecular weight is a value measured by GPC and determined in terms of polystyrene.

  Two or more polyarylene sulfide resins having different melt viscosities may be used in combination. When the weight average molecular weight of the polyarylene sulfide resin used in the present invention exceeds the above range, not only tends to be disadvantageous in terms of melt fluidity, but also the environmental stability of the laser focus of the optical pickup component made of the composition It tends to decrease the sex. Although it is unclear why the environmental stability of the laser focus decreases when the weight average molecular weight increases, it is likely that the anisotropy of deformation due to temperature changes in the molded body will probably promote the orientation of the fibrous filler during molding. Estimated to increase.

  The expanded graphite (B) used in the present invention is obtained by treating raw graphite with a strong acid such as concentrated sulfuric acid or nitric acid and a strong oxidizing agent such as hydrogen peroxide, perchlorate, permanganate, etc. After the formation of an interlayer material, the substrate is washed with water, dehydrated, and heated rapidly to 800-1200 ° C. to vaporize nitric acid and sulfate ions inserted between the graphite layers, generating pressure due to the vaporization inside the graphite. And expanded to 100 to 300 times the original volume, and pulverized into powder. As the expanded graphite obtained by the method as described above, various expanded graphites having different properties such as particle diameter, bulk density, DBP oil absorption and the like are manufactured and commercially available.

The (B) expanded graphite used in the present invention preferably has a DBP oil absorption amount of 200 ml / 100 mg or more, more preferably, in order to obtain the effects of improving the stability of the laser optical axis, the rigidity change due to the thermal cycle, and the split resistance. Is preferably in the range of 250 ml / 100 mg or more, more preferably 280 ml / 100 mg or more. The DBP oil absorption is measured using DBP (dibutyl phthalate) according to the JIS K6221 carbon black test method for rubber (the spatula kneading method). Furthermore, in order to improve the dispersibility during melt-kneading and obtain the stability of characteristic expression, the bulk density is preferably 0.08 g / cm ³ or more, more preferably 0.09 g / cm ³ or more. In the present invention, the bulk density is measured according to JIS K7365 (plastic funnel—measures the bulk density of a material that can be poured from a specified funnel). Examples of the raw graphite for the expanded graphite include highly graphitized materials such as natural graphite, quiche graphite, and pyrolytic graphite. Among these, natural graphite is preferable from the viewpoint of the balance between thermal conductivity and economy. As natural graphite to be used, for example, commercially available products such as CFW50A (trade name, manufactured by Chuetsu Graphite Co., Ltd.) can be used.

Examples of graphite other than (C) expanded graphite used in the present invention include artificial graphite graphitized at a temperature of 2000 ° C. or higher using petroleum coke as a raw material, natural graphite obtained by refining and pulverizing natural products, and the like. Specific examples of natural graphite include scaly graphite, scaly graphite, earthy graphite, and the like. Among these, artificial graphite, scaly graphite and scaly graphite are preferable in terms of thermal conductivity and stability of the laser optical axis. . Moreover, in order to improve the fluidity at the time of melt processing, the bulk density is preferably in the range of 0.20 g / cm ³ or more, more preferably 0.25 g / cm ³ or more.

  From (B) expanded graphite and (C) graphite other than expanded graphite, the porosity between particles is reduced, and the heat conductivity, rigidity change due to the thermal cycle and the split resistance are improved by packing more closely, The particle size distribution is preferably over a wide range. Specifically, the 90% cumulative particle size (D90) and the 10% cumulative particle size (D10) obtained from the cumulative particle size distribution curve measured by the laser diffraction method. The ratio (D90 / D10) is preferably 10 or more, more preferably 11 or more, and still more preferably 13 or more. The upper limit is not particularly limited, but is 1000 considering productivity and the like. The cumulative particle size distribution curve is a distribution curve obtained by integrating the particle sizes measured by the laser light diffraction method from those having a small particle size. Furthermore, in order to maximize the thermal conductivity of (B) expanded graphite and (C) graphite other than expanded graphite used in the present invention, (B) expanded graphite obtained by a laser diffraction method and ( C) The average particle size (50% particle size (D50)) when combined with graphite other than expanded graphite is preferably in the range of 1 to 250 μm, more preferably 40 to 150 μm, and even more preferably 50 to 100 μm. .

  In the present invention, (A) with respect to 100 parts by weight of the thermoplastic resin, the characteristics of expanded graphite used and graphite other than expanded graphite are exhibited with high efficiency and from the viewpoint of balance with melt processability, (B) 20 to 300 parts by weight of expanded graphite and (C) 20 to 300 parts by weight of graphite other than expanded graphite, preferably (B) 40 to 200 parts by weight of expanded graphite and (C) 40 to 200 parts by weight of graphite other than expanded graphite More preferably, (B) 50 to 150 parts by weight of expanded graphite and (C) 50 to 150 parts by weight of graphite other than expanded graphite, and high heat dissipation, stability of the laser optical axis, rigidity due to cooling cycle In order to exhibit change, split resistance, and slidability with high efficiency, the blend ratio (B) / (C) of (B) expanded graphite to (C) graphite other than expanded graphite is 1/9 to 5 / 5, (B) expanded graphite and (C) The blending ratio (B) / (C) with graphite other than the stretched graphite is preferably 1/9 to 4/6, and the blending ratio (B) between the expanded graphite and (C) the graphite other than the expanded graphite (B ) / (C) is more preferably 3/7 to 4/6.

  From the viewpoint of imparting mechanical strength such as rigidity at high temperature to the present invention, it is preferable to add (D) other inorganic filler, and specifically, fibrous or non-fibrous (plate-like, scale-like) Specific examples include, for example, glass fibers, PAN-based and pitch-based carbon fibers, stainless fibers, aluminum fibers, brass fibers, and the like as fibrous fillers. , Organic fibers such as aromatic polyamide fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, barium titanate whisker, boric acid Examples include aluminum whiskers and silicon nitride whiskers. To no particular limitation if those used for reinforcement of resin, such as a long fiber type and short fiber type, chopped strands, may be selected from such milled fiber. The filler may be coated or focused with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

  Specific examples of non-fibrous fillers include mica, talc, kaolin, silica, calcium carbonate, glass beads, glass flakes, glass microballoons, clay, molybdenum disulfide, wollastonite, calcium polyphosphate, graphite, metal powder, Examples include metal flakes, metal ribbons, metal oxides (alumina, zinc oxide, titanium oxide, etc.), carbon nanotubes, and the like. Moreover, silver, nickel, copper, zinc, aluminum, stainless steel, iron, brass, chromium, tin etc. can be illustrated as a specific example of the metal seed | species of metal powder, metal flakes, and a metal ribbon.

  Here, specific examples of the metal species of the metal powder, metal flake and metal ribbon include silver, nickel, copper, zinc, aluminum, magnesium, stainless steel, iron, brass, chromium and tin.

  Moreover, iron, copper, stainless steel, aluminum, brass, etc. can be illustrated as a specific example of the metal seed | species of the said metal fiber.

  Such metal powders, metal flakes, metal ribbons, and metal fibers may all be surface-treated with a surface treatment agent such as titanate, aluminate, and silane.

Specific examples of the metal oxide include SnO ₂ (antimony dope), In ₂ O ₃ (antimony dope) and ZnO (aluminum dope), and these include titanate, aluminum and silane. The surface treatment may be performed with the surface treatment agent.

Specific examples of the nitride include AlN (aluminum nitride), BN (boron nitride), Si ₃ N ₄ (silicon nitride), etc., and these include titanate-based, aluminum-based and silane-based surfaces. Surface treatment may be performed with a treating agent.

  In the present invention, the blending amount of (D) other inorganic filler is preferably blended with 5 to 300 parts by weight of (D) other inorganic filler with respect to 100 parts by weight of (A) thermoplastic resin. (D) 10 to 200 parts by weight of the other inorganic filler is more preferable, and (D) 40 to 150 parts by weight of the other inorganic filler is more preferable.

  In addition, the present invention includes the following (E) fatty acid metal salt, ester-based compound, amide group-containing compound, epoxy-based compound, and phosphate ester from the viewpoint of filler interface bondability and imparting flow improvement during processing. Any one or more additives are preferably added. Specific examples of such additives (E) include sodium stearate, calcium stearate, magnesium stearate, potassium stearate, lithium stearate, and zinc stearate. , Fatty acid metal salts such as barium stearate, aluminum stearate, sodium montanate, calcium montanate, magnesium montanate, potassium montanate, lithium montanate, zinc montanate, barium montanate, aluminum montanate, and derivatives thereof, stearic acid Methyl stearate such as chill, stearic acid stearate, myristic acid ester such as myristyl myristate, montanic acid ester, methacrylic acid ester such as behenyl methacrylate, pentaerythritol monostearate, cetyl 2-ethylhexanoate, palm fatty acid Methyl, methyl laurate, isopropyl myristate, octyldodecyl myristate, butyl stearate, 2-ethylhexyl stearate, isotridecyl stearate, methyl caprate, methyl myristate, methyl oleate, octyl oleate, lauryl oleate, olein Monohydric alcohol esters of fatty acids such as oleyl acid, 2-ethylhexyl oleate, decyl oleate, octidodecyl oleate, and isobutyl oleate And its derivatives, distearyl phthalate, distearyl trimellirate, dimethyl adipate, dioleyl adipate, adipate, ditridecyl phthalate, diisobutyl adipate, diisodecyl adipate, dibutyl glycol adipate, 2-ethylhexyl phthalate, phthalate Fatty acid esters of polybasic acids such as diisononyl acid, didecyl phthalate, tri-2-ethylhexyl trimellitic acid, triisodecyl trimellitic acid, stearic acid monoglyceride, palmitic acid / stearic acid monoglyceride, stearic acid mono / diglyceride, stearic acid / oleic acid・ Fatty acid esters of glycerin such as mono-diglyceride and behenic monoglyceride and their derivatives, sorbitan tristearate, sorbitan Monostearate, sorbitan monostearate, sorbitan distearate, sorbitan monopalmitate, sorbitan monostearate, polyethylene glycol monostearate, polyethylene glycol distearate, polypropylene glycol monostearate, pentaerythritol monostearate, sorbitan mono Laurate, sorbitan trioleate, sorbitan monooleate, sorbitan sesquioleate, sorbitan monolaurate, polyoxymethylene sorbitan monolaurate, polyoxymethylene sorbitan monopalinate, polyoxymethylene sorbitan monostearate, polyoxymethylene sorbitan monooleate , Polyoxymethylene sorbitan tetraoleate, polyethylene glycol, polyethylene Glycol monolaurate, polyethylene glycol monooleate, polyoxyethylene bisphenol A lauric acid ester, fatty acid esters of polyhydric alcohols such as pentaerythritol, pentaerythritol monooleate, and derivatives thereof, ethylene bisstearylamide, ethylenebisoleylamide , Stearyl erucamide, ethylene bisoctamide, ethylene bisdecanamide, and mixtures thereof, amide group-containing compounds, novolac phenyl type, bisphenol type monofunctional or polyfunctional epoxy compounds, aromatics such as triphenyl phosphate Examples thereof include phosphate esters such as phosphate esters and aromatic condensed phosphate esters.

  (E) The addition amount of the additive is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 10 parts by weight, further preferably 100 parts by weight of the total amount of the components (A) to (D). Is selected in the range of 0.3 to 8 parts by weight, particularly preferably 0.3 to 6 parts by weight.

  (E) If the additive amount is too much than the range of the present invention, the surface of the obtained molded product bleeds out, thereby causing peeling of the interface between the thermoplastic resin and the filler and lowering the mechanical properties. There is a tendency.

  In the resin composition of the present invention, other components, such as antioxidants and heat stabilizers (hindered phenol-based, hydroquinone-based, phosphite-based and substituted products thereof, etc.), as long as the effects of the present invention are not impaired. Weathering agents (resorcinol, salicylate, benzotriazole, benzophenone, hindered amine, etc.), release agents and lubricants, pigments (cadmium sulfide, phthalocyanine, carbon black for coloring, etc.), dyes (nigrosine, etc.), crystal nucleating agents (Talc, silica, kaolin, clay, etc.), plasticizer (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agent (alkyl sulfate type anionic antistatic agent, quaternary ammonium salt type cationic type) Nonionic system such as antistatic agent, polyoxyethylene sorbitan monostearate Antistatic agents, betaine-based amphoteric antistatic agent, etc.), can be added a flame retardant, other polymers.

  The resin composition of the present invention is usually produced by a known method. For example, it is prepared by pre-mixing other necessary additives such as the components (A) to (D) and the component (E) or without supplying them to an extruder or the like and sufficiently melt-kneading them. The Moreover, when adding (B)-(D) component, in order to suppress the breakage of the fiber of a fibrous filler, Preferably (A) thermoplastic resin and (B), (C), and other required additions It is prepared by introducing the agent from the extruder and supplying the component (D) to the extruder by using a side feeder, or (A) adding the thermoplastic resin and other necessary additives to the extruder. It is prepared by charging from the beginning and supplying the components (B), (C), and (D) to the extruder by using a side feeder.

  When producing a resin composition, for example, melt-kneading at 180 to 350 ° C. using a single-screw extruder, twin-screw, three-screw extruder and kneader-type kneader equipped with a “unimelt” (R) type screw. To obtain a composition.

  In addition, when a large amount of filler is added, for example, a highly filled resin composition is obtained in which the amount of addition exceeds 200 parts by weight with respect to 100 parts by weight of (A) thermoplastic resin. As a method, for example, as disclosed in JP-A-8-1663, a method of extruding the head portion of the extruder and extruding, coarsely pulverizing and uniformly blending, or a method of compressing the raw material into a tablet can be mentioned. In particular, the method of tableting by compressing the raw material is preferable from the viewpoint of the quality stability of the obtained composition.

  In the present invention, a tablet refers to a granular material obtained by compacting a raw material containing a powdery raw material in a solid phase. Such a tablet can be obtained by compression molding a raw material containing a powdery raw material in a solid phase. Can do. In the above, the solid phase state means that the thermoplastic resin component contained in the raw material is not melted. For the compression molding, it is preferable to use a molding machine having a compression roll such as a tableting machine (rotary, single-shot, double, triple) or briquette machine.

As a specific method for tableting, for example, a thermoplastic resin powder and an inorganic filler are uniformly blended in a solid phase using a Banbury mixer, kneader, roll, single-screw or twin-screw extruder, and a tableting machine or It can be obtained by tableting with a molding machine having a compression roll. Also, the thermoplastic resin raw material and inorganic filler are dry blended in advance using a Banbury mixer, kneader, or roll, or melt blended once using a single or twin screw extruder, etc., and cooled. After being pulverized into a powder form, it can be formed into tablets (tablets) with a tableting machine or a molding machine having a compression roll. In this case, the thermoplastic resin component used for melt kneading is not particularly limited as long as it can be melt kneaded, either in powder form or pellet form, but it is a powder from the viewpoint of reducing variation in characteristics due to poor dispersion of inorganic filler. Preferably, it is in the form of a pulverized product. In addition, when the composition previously melt-kneaded using a single-screw or twin-screw extruder is powdered, if the amount of inorganic filler used is large, the fluidity deteriorates, so the pellet cannot be extruded from the die. However, in this case, as described in JP-A-8-1663, kneading and extrusion can be performed with the head portion of the extruder being opened. When the amount of the inorganic filler is large, a flaky composition may be obtained. In the present invention, if necessary, a pellet or flake composition obtained by melt-kneading in advance by these methods is cooled and pulverized to form a powder and then tableted. In addition, these methods can be combined into tablets. That is, a raw material selected from the following (a) to (f) can be adjusted to have a desired content and tableted.
(A) (A) Thermoplastic resin (B) (B) Expanded graphite (C) (C) Graphite other than expanded graphite (2) (D) Other inorganic fillers (E) (E) Fatty acid metal salts, esters One or more of a compound, an amide group-containing compound, an epoxy compound, and a phosphoric ester, and two or more selected from the components (A) to (E), and the component (A) is essential A composition formed by melt-kneading the components to be melted, preferably the lump and powder thereof. Among the above methods, the raw materials of the above (a) to (e) and, if necessary, (f) A method in which a mixture obtained by uniformly blending these raw materials in a solid phase is formed into a tablet by using a tableting machine or a molding machine having a compression roll.

  As the powder of the component (A), those available in powder form such as polyarylene sulfide resin may be used. It can also be obtained by pulverizing the pellets at room temperature or by freeze pulverization. The freeze pulverization can be carried out by using a generally known hammer type pulverizer, cutter type pulverizer, or stone mill type pulverizer after being frozen with dry ice or liquid nitrogen. The thermoplastic resin powder used in the present invention includes particles obtained by measurement based on a laser diffraction type particle size distribution measurement method from the viewpoint of making the composition uniform between the obtained tablets and improving the handleability of the obtained tablets. The number average particle diameter of the maximum major axis is preferably 1000 μm or less, more preferably 800 μm or less, and even more preferably 500 μm or less. In order to obtain a powder having such a particle size, the powder obtained by pulverization or the like may be appropriately sieved using a sieve having a desired size.

  As the tablet shape of the resin composition used in the present invention, when considering shape retention during transportation and easy crushability during molding, for example, cylindrical, elliptical columnar, truncated cone shape, spherical, elliptical spherical, egg shape The shape, Macek type, disk shape, cubic shape and prismatic shape can be mentioned. Among these, a cylindrical shape, an elliptical column shape, a truncated cone shape, a spherical shape, an elliptic spherical shape, an egg shape, and a Macek shape are preferable from the viewpoint of measurement stability during processing.

  Further, the tablet size of the tablet is preferably a bottom surface of 15 mm diameter or less × length of 20 mm or less, in particular, the maximum value of the bottom surface diameter or length (height) is preferably less than 15 mm, and the minimum value is 1 mm or more. It is preferable that As for the method of defining the maximum diameter and the minimum diameter with respect to those having a bottom surface that is not circular, when the maximum diameter of the circumscribed circle is specified, the maximum diameter is preferably less than 15 mm, 1 mm or more, more preferably 12 mm. Hereinafter, it is good that it is 1.5 mm or more.

  In addition, in order to keep the shape stable during transportation, the compression fracture strength value (crush strength value) when pressure is applied perpendicularly to the side of the tableting surface of the tablet or the compression surface of the compression roll, Preferably it is 5-100N, More preferably, it is 15-80N. As a method for obtaining a preferable crushing strength value, for example, it is most dependent on the raw material composition, and by adding additives such as ester compounds, amide group-containing compounds, phosphate esters, or in the tableting process, A method of supplying raw materials uniformly to the supply pocket, a method of reducing the number of rotations of the compression roll and extending the pressurization time of the material on the compression roll, and using a feed screw in the hopper, which is effective before roll compression. A high tablet density and a high crushing strength can be obtained by a simple deaeration and pre-compression method. The crushing strength value is measured by placing a tablet on a strain gauge such as a load cell, and lowering the indenter at a low speed (preferably 0.1 to 2.0 mm / sec), and straining the tablet at the time of compressive fracture. A method of measuring the pressure indicated by the gauge can be used.

  By using such a method, it becomes possible to obtain a resin composition highly filled with a filler.

  As a molding method for molding the resin composition of the present invention, a normal molding method (injection molding, press molding, injection press molding, etc.), a gas injection molding, a musel molding method, or the like can be used. Although it can be processed into a molded article, a sheet, a case (housing), etc., in consideration of productivity, injection molding or injection press molding is preferably employed. The molded product thus obtained makes the best use of the characteristics of the inorganic filler to be used and is capable of being melt-molded. For example, high heat dissipation applications, metal replacement applications, ceramic replacement applications, electromagnetic wave shielding applications, high precision parts ( Low dimensional change), useful for high conductivity applications, specifically, various cases, gear cases, LED lamp related parts, connectors, relay cases, switches, variable capacitor cases, optical pickup lens holders, optical pickup slide bases, Various terminal boards, transformers, printed wiring boards, liquid crystal panel frames, power modules and their housings, plastic magnets, semiconductors, liquid crystal display parts, lamp covers for projectors, FDD carriages, FDD chassis, actuators, HDD parts such as chassis Computer related parts Electric / electronic parts represented by: audio equipment such as VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave oven parts, acoustic parts, audio laser discs (registered trademark), compact discs, digital video discs Houses represented by parts, lighting parts, refrigerator parts, air conditioner parts, office electrical product parts, office computer-related parts, telephone-related parts, facsimile-related parts, printer heads and parts related to printing heads and transfer rolls, Cleaning jigs, motor parts, microscopes, binoculars, cameras, optical instruments such as watches, precision machine related parts; alternator terminals, alternator connectors, IC regulators, light dimmer potentiometer bases, motor core sealing materials, SCHRATER components, power seat gear housings, thermostat bases for air conditioners, air conditioner panel switch boards, horn terminals, electrical component insulation plates, lamp housings, ignition device cases and other automotive / vehicle related parts, personal computer housings, mobile phone housings, etc. In the field of information and communications, chip antennas, a wide range of fields such as housings such as installation antennas that require shielding properties such as electromagnetic waves, etc., in addition, high dimensional accuracy, electromagnetic wave shielding properties, barrier properties such as gas and liquid are required CDs and DVDs that are useful in applications that require partition walls, heat and electrical conductivity, equipment for outdoor installations, or building members, and that are particularly lightweight and require freedom of shape. , For optical pickup parts such as laser disk and magneto-optical disk, In particular, it is suitably used for DVDs, laser discs, optical pickup slide bases of magneto-optical discs, lens holders, and the like that require heat dissipation.

  Hereinafter, although an example is given and the present invention is explained in detail, the gist of the present invention is not limited only to the following examples.

Reference Example 1 Preparation of Thermoplastic Resin PPS In a 20 liter autoclave equipped with a stirrer and a valve at the bottom, 2383 g (20.0 mol) of 47% sodium hydrosulfide (Sankyo Kasei), 831 g of 96% sodium hydroxide (19. 9 mol), 3960 g (40.0 mol) of N-methyl-2-pyrrolidone (NMP), and 3000 g of ion-exchanged water, and gradually heated to 225 ° C. over about 3 hours while passing nitrogen at normal pressure. After distilling 4200 g and NMP 80 g, the reaction vessel was cooled to 160 ° C. The residual water content in the system per mole of the alkali metal sulfide charged was 0.17 mole. The amount of hydrogen sulfide scattered per mole of the alkali metal sulfide charged was 0.021 mol.

  Next, 2942 g (20.0 mol) of p-dichlorobenzene (Sigma Aldrich) and 1515 g (15.3 mol) of NMP were added, and the reaction vessel was sealed under nitrogen gas. Then, while stirring at 400 rpm, the temperature was increased from 200 ° C. to 227 ° C. at a rate of 0.8 ° C./min, then increased to 274 ° C. at a rate of 0.6 ° C./min, and held at 274 ° C. for 50 minutes. Then, the temperature was raised to 282 ° C. Open the extraction valve at the bottom of the autoclave, pressurize with nitrogen, flush the contents into a vessel with a stirrer over 15 minutes, stir at 250 ° C for a while to remove most of the NMP, polyphenylene sulfide (PPS) and Solids containing salts were collected.

  The obtained solid and 15120 g of ion-exchanged water were placed in an autoclave equipped with a stirrer, washed at 70 ° C. for 30 minutes, and suction filtered through a glass filter. Next, 17280 g of ion-exchanged water heated to 70 ° C. was poured into a glass filter, and suction filtered to obtain a cake.

  The obtained cake and 11880 g of ion-exchanged water were charged into an autoclave equipped with a stirrer, and the inside of the autoclave was replaced with nitrogen, and then the temperature was raised to 192 ° C. and held for 30 minutes. Thereafter, the autoclave was cooled and the contents were taken out.

  The contents were subjected to suction filtration with a glass filter, and then 17280 g of ion-exchanged water at 70 ° C. was poured into the contents, followed by suction filtration to obtain a cake. The obtained cake was dried with hot air at 80 ° C., and further dried under vacuum at 120 ° C. for 24 hours to obtain dry PPS. The obtained PPS had a weight average molecular weight in terms of polystyrene of 20000.

  The weight average molecular weight was measured by the following method.

5 mg of polymer and 5 g of 1-chloronaphthalene were weighed into a sample bottle, placed in a high-temperature filter set at 210 ° C. (SSC-9300 manufactured by Senshu Kagaku), and heated for 5 minutes (1 minute preheating, 4 minutes stirring), The sample was prepared by taking it out from the high-temperature filter and leaving it to room temperature. Subsequently, the weight average molecular weight was measured under the following measurement conditions.
GPC measurement condition device: Senshu Science SSC-7100
Column name: Senshu Science GPC3506 × 1
Eluent: 1-chloronaphthalene (1-CN)
Detector: Differential refractive index detector Detector sensitivity: Range 8
Detector polarity: +
Column temperature: 210 ° C
Pre-temperature bath temperature: 250 ° C
Pump bath temperature: 50 ° C
Detector temperature: 210 ° C
Sample-side flow rate: 1.0 mL / min
Reference side flow rate: 1.0 mL / min
Sample injection amount: 300 μL
Calibration curve preparation sample: polystyrene.

  PA6 (nylon 6): CM1001 (manufactured by Toray Industries, Inc.) is immersed in liquid nitrogen, pulverized with a sample mill (SK-M type, manufactured by Kyoritsu Riko Co., Ltd.), and classified with a sieve at 42 mesh pass and 80 mesh on. A number average particle diameter of 300 μm was obtained.

  LCP (Liquid Crystal Polyester Resin): “Siberus” L201E (manufactured by Toray Industries, Inc.) is dipped in liquid nitrogen, pulverized with a sample mill (SK-M type, manufactured by Kyoritsu Riko Co., Ltd.), 80 mesh pass with sieve, 150 mesh on And a number average particle diameter of 150 μm was obtained.

  PBT (polybutylene terephthalate): 1100S (manufactured by Toray Industries, Inc.) is immersed in liquid nitrogen, pulverized with a sample mill (SK-M type manufactured by Kyoritsu Riko Co., Ltd.), and classified with a sieve at 42 mesh pass and 80 mesh on. And a number average particle diameter of 300 μm was obtained.

Reference Example 2 Expanded graphite B: BSP-60AS (raw material: natural graphite, average particle size 60 μm, DBP oil absorption 288 ml / 100 mg, bulk density 0.093 g / cm ³ , manufactured by Chuetsu Graphite)

Reference Example 3 Graphite C other than expanded graphite: natural graphite, CFW50A (flaky graphite, average particle size 50 μm, bulk density 0.27 g / cm ³ , manufactured by Chuetsu Graphite)
The DBP oil absorption was measured using DBP (dibutyl phthalate) according to the JIS K6221 carbon black test method for rubber (the spatula kneading method). The bulk density was measured according to JIS K7365 (Plastic funnel—measures bulk density of material that can be poured from a specified funnel).

Reference Example 4 Other inorganic filler D-1: carbon fiber, MLD1000 (fibrous filler, PAN, average fiber length 150 μm, manufactured by Toray Industries, Inc.)
D-2: Alumina, AL-32B (crushed alumina, average particle size 2 μm, manufactured by Sumitomo Chemical Co., Ltd.)
In addition, said average particle diameter is the number average measured based on the laser diffraction type particle size distribution measuring method.

Reference Example 5 Additive (use 42 mesh pass through sieve)
E-1: “PX-200” (Daihachi Chemical Industry Co., Ltd., powdered aromatic condensed phosphate ester, CAS No. 139189-30-3).
E-2: “WH255” (a long-chain alkyl aliphatic amide group-containing compound manufactured by Kyoei Chemical Co., Ltd.).

Examples 1-6, Comparative Examples 1-7
The thermoplastic resin of Reference Example 1 and the fillers shown in Reference Examples 2 to 4 are blended in a ribbon blender in the amounts shown in Table 1, and are represented by a PCM30 with a three-hole strand die head (biaxial extruder; manufactured by Ikekai Tekko Co., Ltd.). Melt kneading was carried out at the resin temperature shown in FIG. Subsequently, after drying for 4 hours in a 130 degreeC hot-air oven, evaluation mentioned later was performed.

Examples 7 to 10, Comparative Examples 8 to 10
A rotary punch made by Tsukishima Kikai Co., Ltd. equipped with an automatic raw material supply feeder by blending the thermoplastic resin of Reference Example 1, the fillers shown in Reference Examples 2 to 4 and the additive of Reference Example 5 with a Henschel mixer in the amounts shown in Table 1. A 6 mm diameter × 3 mm long cylindrical tablet (tablet resin composition) (maximum value 6 mm, minimum value 3 mm) was obtained by tableting at room temperature using a tablet machine. Subsequently, after drying with a 130 degreeC hot-air dryer for 4 hours, the following evaluation was performed.

(1) Fluidity An injection molding machine UH1000 (manufactured by Nissei Plastic Industry Co., Ltd.) is used for injection molding at the molding lower limit pressure at the resin temperature and mold temperature shown in Table 1, and an optical pickup slide base having the shape shown in FIG. An injection molded product (a rectangular parallelepiped having a length of 40 mm, a width of 30 mm, and a thickness of 5 mm) 1 was obtained. At that time, the minimum filling pressure required to fill the molded product was measured (the lower the pressure, the better the fluidity (moldability)).

  FIG. 1 is a perspective view of an injection molded product provided with a half mirror. A central cutout portion (a square with a side of 6 mm) is provided at the center of the upper surface of the injection molded product 1, and a half mirror 2 is installed.

(2) Thermal cycle test (1) (strength retention)
Using an injection molding machine UH1000 (manufactured by Nissei Plastic Industrial Co., Ltd.), a square-shaped product of 80 mm × 80 mm × thickness 3 mm (film gate) was molded at the minimum pressure + 5 MPa at the resin temperature and mold temperature shown in Table 1. The obtained molded product was subjected to a thermal cycle test with a thermal shock device (TSA-70L manufactured by ESPEC), then cut into two pieces with a width of 12.7 mm from the center in the flow direction, and conformed to ASTM D790. The bending strength was measured, and the strength retention was evaluated by the following formula. It can be said that the smaller this value is, the better the rigidity change due to temperature change.
Strength retention (%) = (bending strength before cooling test / bending strength after cooling test) × 100

  The conditions of the cold test were 1000 cycles, where normal temperature (23 ° C.) → temperature drop at 5 minutes → hold at −40 ° C. for 30 minutes → temperature rise at 5 minutes → hold at 30 ° C. for 30 minutes for one cycle.

(3) Thermal cycle test (2) (number of heat shock defects)
Using an injection molding machine UH1000 (manufactured by Nissei Plastic Industry Co., Ltd.), injection molding is performed under the conditions of the molding temperature lower limit pressure + 0.49 MPa at the resin temperature and mold temperature shown in Table 1, and the optical pickup slide base having the shape shown in FIG. A molded product (a rectangular parallelepiped having a length of 40 mm, a width of 30 mm, and a thickness of 5 mm) was obtained. As shown in FIG. 1, the half mirror 2 was installed in the center notch part (6 mm side square) of the obtained molded article 1, and the heat cycle test was done with the thermal shock device (TSA-70L by ESPEC).

  The test conditions are as follows: normal temperature (23 ° C.) → temperature drop at 5 minutes → hold at −40 ° C. for 30 minutes → temperature rise at 5 minutes → hold at 30 ° C. for 30 minutes for 1000 cycles, and half mirror The number of defectives including peeling of the molded product and cracks on the surface of the molded product was measured.

(4) Evaluation of optical axis stability (optical axis fluctuation value) Injection molding using the injection molding machine UH1000 (manufactured by Nissei Plastic Industry Co., Ltd.) at the resin temperature and mold temperature shown in Table 1 and the molding lower limit pressure +0.49 MPa. As a result, a molded article (a cuboid having a length of 40 mm, a width of 30 mm, and a thickness of 5 mm) 1 simulating the optical pickup slide base shown in FIG. 1 was obtained. As shown in FIG. 1, a half-mirror 2 is installed in the central cutout portion (a square with a side of 6 mm) of the molded product 1 obtained, and a semiconductor laser auto having a focal length of 200 mm, a wavelength of 650 nm, and an output of 0.3 mW in a constant temperature layer. The laser beam a oscillated from the collimator was applied, and the reflected laser beam b was received by a CCD camera. Then, with the position of the reflected laser beam at 30 ° C. as the origin, the temperature was raised to 90 ° C. over 30 minutes, and then the temperature was lowered from 90 ° C. to 30 ° C. over 30 minutes. The value was measured. It can be said that the smaller this value, the better the environmental stability of the laser focus.

(5) Heat dissipation (thermal conductivity)
Using an injection molding machine UH1000 (manufactured by Nissei Plastic Industry Co., Ltd.), injection molding is performed under the conditions of the molding lower limit pressure + 0.49 MPa at the resin temperature and mold temperature shown in Table 1, and the optical pickup slide base having the shape shown in FIG. A simulated molded article (a rectangular parallelepiped having a length of 40 mm, a width of 30 mm, and a thickness of 5 mm) was obtained. The d surface of the obtained molded product was placed in contact with a stage heated to 70 ° C. of a micro melting point microscope (manufactured by YANAKO), a temperature sensor was installed at the center of the c surface, and the sensor temperature after about 30 minutes Was measured at a constant temperature (the higher the sensor temperature, the better the heat is transferred, the heat is not trapped, and the heat dissipation is better).

(6) Sliding property Using an injection molding machine UH1000 (manufactured by Nissei Plastic Industry Co., Ltd.), the resin temperature and mold temperature shown in Table 1 were injection molded under the conditions of molding lower limit pressure + 0.49 MPa, and the shape shown in FIG. A molded article 3 for evaluation of sliding imitating a size optical pickup component was obtained. 2 is a developed view of the molded article 3 for slidability evaluation imitating the optical pickup component, FIG. 2a is a top view thereof, FIG. 2b is a side view of FIG. 2a viewed from the direction B, and FIG. FIG. 2d is a side view as seen from the direction B in FIG. Next, the molded product is sandwiched between the metal pin guide portion 4 and the metal pin insertion shaft hole portion 5 with a rod made of 3 mmφ SUS420 material, an 8 g weight is placed on the molded product, and the molded product is heated to 100 ° C. with a cartridge heater. In a temperature-controlled state, after reciprocating 1000 times 30 mm left and right, the inner diameter of the metal pin insertion shaft hole 5 was measured using a universal projector, and the dimensional change rate (maximum value) was evaluated.
Dimensional change rate (%) = [(maximum inner diameter before test−maximum inner diameter after test) / inner diameter before test] × 100

  As is apparent from the results in Table 1, the molded product obtained from the resin composition of the present invention stabilizes the optical axis of the laser, and has high heat dissipation, sliding characteristics, and rigidity that were not obtained conventionally. It can be seen that balancing is possible. Moreover, melt molding is possible, and according to this, productivity can be greatly improved.

FIG. 1 is a perspective view of a molded product imitating an optical pickup slide base provided with a half mirror, which was used for evaluation of optical axis stability in Examples. FIG. 2 is a development view of a molded product for slidability evaluation imitating an optical pickup component used for evaluating the optical axis stability in the example, FIG. 2a is a top view thereof, and FIG. FIG. 2c is a side view seen from the direction B in FIG. 2a, and FIG. 2d is a bottom view.

Explanation of symbols

1. Injection molded product Half mirror 3. Molded product for slidability evaluation 4. Metal pin guide part Metal pin insertion part shaft hole part a. Incident direction of laser light oscillated from semiconductor laser autocollimator b. Reflection direction of reflected laser light c. Temperature sensor mounting part
d. The part in contact with the stage of the micro melting point microscope

Claims (5)

(A) 20 to 300 parts by weight of expanded graphite and (C) 20 to 300 parts by weight of graphite other than expanded graphite with respect to 100 parts by weight of the thermoplastic resin, and (B) expanded graphite And (C) The resin composition, wherein the blending ratio of graphite other than expanded graphite is (B) / (C) = 1/9 to 5/5. The resin composition according to claim 1, further comprising (D) 5 to 300 parts by weight of other inorganic fillers with respect to (A) 100 parts by weight of the thermoplastic resin. (A) The resin composition according to claim 1 or 2, wherein the thermoplastic resin is at least one selected from a polyamide resin, a non-liquid crystalline polyester resin, a liquid crystal polymer, and a polyarylene sulfide resin. An optical molded article obtained by injection molding or injection press molding the resin composition according to claim 1. The optical molded article according to claim 4, wherein the optical molded article is used for an optical pickup component.

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