JP4747561B2 - Polyphenylene sulfide resin composition - Google Patents

Description

  The present invention relates to a polyphenylene sulfide resin composition from which a molded product having excellent surface smoothness and strength can be obtained. More specifically, the present invention has excellent surface smoothness for forming a metal film, and mechanical properties. The present invention relates to a polyphenylene sulfide resin composition having an excellent balance of properties such as low gas properties and excellent slidability.

  Since polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) has suitable properties as engineering plastics such as excellent heat resistance, rigidity, dimensional stability, and flame retardancy, various types are mainly used for injection molding. Widely used in electrical / electronic parts, machine parts and automobile parts.

  However, when it is used for a molded product that is excellent in surface smoothness and requires strength, an inorganic filler is blended. However, when an inorganic filler having a large particle size is blended, the surface smoothness is deteriorated. Therefore, in order to improve the surface smoothness, it is necessary to reduce the particle size of the inorganic filler. However, when the particle size of the inorganic filler is reduced, there is a problem that the impact strength is lowered. Thus, it has been difficult to achieve both surface smoothness and impact strength of the molded product.

  In addition, when forming a mirror surface by coating a metal such as aluminum on the surface of a molded article, if the metal is coated by a method such as vapor deposition without any surface treatment after molding of the resin, There is a problem that sufficient surface smoothness cannot be obtained due to fine unevenness caused by the filler present on the surface, and a PPS resin composition that can satisfy these problems has not been obtained yet.

Several fillers have been studied so far for the purpose of improving the high surface smoothness. For example, Patent Document 1 discloses a composition in which a fibrous filler and barium sulfate are blended with a PPS resin. However, according to the study by the present inventors, when the amount of the fibrous filler is too large, and when specifically described barium sulfate is used, the particle size is too large and sufficient surface smoothness cannot be obtained. I understood it. Further, it has been found that if only barium sulfate and a fibrous filler are used in combination, the metal film is formed and then heat-treated to cause fogging and a sufficient surface appearance cannot be obtained. Patent Document 2 describes a coating composition in which barium sulfate is blended with a PPS resin. This coating composition is coil-coated or spray-coated as a dispersion, and is then heat-cured to adhere to a coating object. A coating film having excellent properties can be obtained, which is completely different from a composition obtained by melt-kneading each component as in the present invention. Patent Document 3 discloses a composition in which barium sulfate is blended with a PPS resin. However, since the particle size is too large even when barium sulfate specifically described is used, sufficient surface smoothness and appearance are obtained. It was not obtained, and it was also found that the mechanical properties such as impact resistance were inferior.
Japanese Patent No. 2772342 (page 1-4) Japanese Patent Publication No. 5-5870 (page 1-2) Japanese Patent Laid-Open No. 3-185069 (page 1-4)

  The present invention maintains the excellent heat resistance, rigidity, dimensional stability, flame retardancy, and the like of the conventional polyphenylene sulfide resin described above, and is excellent in strength, low gas resistance, slidability, and particularly excellent impact strength, metal An object of the present invention is to provide a PPS resin composition having both surface smoothness for forming a film.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the above-mentioned problem is caused by using a PPS resin composition containing a specific size of barium sulfate and a specific size of calcium carbonate or kaolin. The inventors have found that the problem can be solved, and have arrived at the present invention.
That is, the present invention
(1) (A) with respect to the polyphenylene sulfide resin 100 parts by weight, (B) wa Rasutenaito textiles 5-25 parts by weight, (C) 10 to 250 parts by weight of barium sulfate having an average particle size of less than 2.5 [mu] m, (D ) Polyphenylene sulfide resin composition obtained by melt-kneading 0.1 to 150 parts of one or more non-fibrous inorganic fillers selected from calcium carbonate having an average particle diameter of 1 μm to 15 μm and kaolin having an average particle diameter of 0.5 μm to 15 μm object,
(2) The polyphenylene sulfide resin composition according to (1), wherein the average fiber diameter of the (B) wollastonite fiber is 8 μm or less,
(3) The polyphenylene sulfide resin composition according to any one of (1) and (2), wherein the polyphenylene sulfide resin composition has a heat loss of not more than 0.4% by weight at 320 ° C. for 2 hours,
(4) Melt flow rate of polyphenylene sulfide resin composition (measured using a melt indexer under conditions of 315.5 ° C., 5-minute residence, load 2160 g (orifice diameter 2.095 mm, length 8.00 mm)) The polyphenylene sulfide resin composition according to any one of (1) to (3), in which is 15 g / 10 min to 150 g / 10 min,
(5) The polyphenylene sulfide resin composition according to any one of (1) to (4), wherein (C) barium sulfate is surface-treated.
(6) (A) The polyphenylene sulfide resin composition according to any one of (1) to (5), in which the polyphenylene sulfide resin has a heat loss of 1.0% by weight or less at 371 ° C. for 1 hour,
(7) The polyphenylene sulfide resin composition according to any one of (1) to (6), which is used for a light reflecting component by forming a metal film on the surface after forming a molded product.

  The present invention maintains the excellent heat resistance, rigidity, dimensional stability, flame retardancy, etc. of the above-mentioned conventional polyphenylene sulfide resin, and is excellent in strength, low gas property, slidability, and deposits a particularly excellent metal film. An object of the present invention is to provide a PPS resin composition having both surface smoothness and impact strength.

  Next, the present invention will be described more specifically.

  The PPS resin used in the present invention is a polymer having a repeating unit represented by the following structural formula (I),

  From the viewpoint of heat resistance, the polymer preferably contains 70 mol% or more, more preferably 90 mol% or more of a polymer containing a repeating unit represented by the above structural formula. In addition, about 30 mol% or less of the repeating units of PPS may be composed of repeating units having the following structure.

  The PPS resin is obtained by a method for obtaining a polymer having a relatively small molecular weight obtained by a production method represented by Japanese Patent Publication No. 45-3368, or Japanese Patent Publication Nos. 52-12240 and 61-7332. It can be produced by a known method such as a method for obtaining a polymer having a relatively large molecular weight as described.

  The PPS resin obtained as described above may be used as it is, or it may be used for crosslinking / polymerization by heating in air, heat treatment under an inert gas atmosphere such as nitrogen or reduced pressure, organic solvent, hot water. It is also possible to use after washing with an acid aqueous solution or the like. Furthermore, it is also possible to use a mixture of two or more different molecular weight distributions.

  The MFR of the PPS resin used in the present invention is not particularly limited as long as it can be melt kneaded. However, the conditions are as follows: 315.5 ° C., 5-minute residence, load 5000 g (orifice diameter 2.095 mm, length 8.00 mm) The measured value using a melt indexer is preferably 10,000 g / 10 min or less, more preferably 5000 g / 10 min or less, and further preferably 2000 g / 10 min or less. Although there is no restriction | limiting in particular as a minimum, From the point of melt viscosity, it is good that it is 10 g / 10min or more, and it is more preferable that it is 50 g / 10min or more.

  The PPS resin used in the present invention has a heat loss of 371 ° C. for 1 hour of preferably 1.0% by weight or less in that the amount of generated gas can be suppressed, and particularly preferably 0.8% by weight or less. More preferably, it is 0.7 weight% or less. Although the lower limit is preferable, 0.05% by weight or more usually provides a sufficient effect. For loss on heating, 1 g of PPS resin is put in an aluminum cup, preliminarily dried in an atmosphere at 150 ° C. for 1 hour, then weighed, treated in air at 371 ° C. for 1 hour, and then weighed again. The weight loss due to the treatment at 371 ° C. is divided by the weight before the treatment, and the weight loss is expressed as a percentage.

  The production method for obtaining the PPS resin having the above properties is not particularly limited as long as the above properties can be obtained, but the polymer is a substantially linear polymer with few impurities, and the desired properties are obtained. A method of washing with an organic solvent, hot water, an acid aqueous solution, or the like until is obtained. In particular, it is more preferable that the PPS resin is reinforced at 371 ° C. for 1 hour with a weight loss of 0.5% by weight or less.

  In the case of washing with an organic solvent, the organic solvent to be used is not particularly limited as long as it does not have an action of decomposing PPS. For example, nitrogen-containing polar solvents such as N-methylpyrrolidone, dimethylformaldehyde, dimethylacetamide, 1,3-dimethylimidazolidinone, hexamethylphosphoramide, piperazinones, sulfoxides and sulfones such as dimethylsulfoxide, dimethylsulfone, and sulfolane Solvents, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, acetophenone, ether solvents such as dimethyl ether, dipropyl ether, dioxane, tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene dichloride, chloroethylene , Halogenated solvents such as monochloroethane, dichloroethane, tetrachloroethane, perchloroethane, chlorobenzene, methanol, ethanol, propanol, Alcohol, pentaol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, polypropylene glycol and other alcohol-phenol solvents, and benzene, Examples thereof include aromatic hydrocarbon solvents such as toluene and xylene.

  There is no restriction | limiting in particular also about washing | cleaning temperature, Usually, about normal temperature-about 300 degreeC are selected. In the case of washing with an acid aqueous solution, the acid to be used is not particularly limited as long as it does not have an action of decomposing PPS, and examples thereof include acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, silicic acid, carbonic acid, and propyl acid. Moreover, it can also be used after performing various treatments such as activation with a functional group-containing compound such as an acid anhydride group, an epoxy group, or an isocyanate group.

In the present invention , wollastonite fiber is used as the (B) fibrous filler .

  The average fiber diameter of the above (B) is preferably 8 μm or less, and more preferably 7 μm or less. There is no particular limitation on the lower limit, and it is preferable that the lower limit is as small as possible. When the average fiber diameter exceeds 8 μm, the surface smoothness tends to decrease. In general, the average fiber diameter is a volume-based average fiber diameter determined based on a diameter distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer. However, the ratio of the fiber length L to the fiber diameter D (L / D) is as large as 25 or more, and the average fiber diameter of whiskers and the like not suitable for laser diffraction particle size distribution measurement is a weight measured by an ordinary method using an electron scanning microscope Use the average fiber diameter. Moreover, there is no restriction | limiting in particular about purity.

No particular limitation is imposed on the L / D of wollastonite fibers (B) above, but is preferably from 3 to 25, more preferably 4 to 25. As L / D increases, the strength and rigidity increase. However, when the fiber diameter is large and L / D is large, the surface smoothness decreases, so when using a fiber with a large fiber diameter such as wollastonite, L / D is low. 3-25 extent is preferable.
The blending amount of the (B) fibrous filler is 5 to 25 parts by weight, preferably 5 to 15 parts by weight, based on 100 parts by weight of the (A) PPS resin. If it exceeds 25 parts by weight, the surface smoothness is lowered, which is not preferable. Further, in order to sufficiently obtain the effect of adding the (B) fibrous filler, the amount is more preferably 10 parts by weight or more.

The wollastonite fiber (B) can be surface-treated within a range not impairing the effects of the present invention. Examples of the treating agent include a surface treating agent and a sizing agent. Compounds, isocyanate compounds, silane compounds, titanate compounds, borane treatment, and the like.

  The barium sulfate (C) used in the present invention may be either barite powder obtained by pulverizing barite or precipitated barium sulfate produced by a chemical reaction, but preferably precipitated barium sulfate is used.

  The (C) barium sulfate has an average particle size of less than 2.5 μm, preferably an average particle size of 1.5 μm or less. Although there is no restriction | limiting in particular in a minimum, A sufficient effect can be acquired if it is 0.1 micrometer or more normally. If the average particle diameter exceeds 2.5 μm, both surface smoothness and impact strength are lowered, which is not preferable. The average particle size is a volume-based average particle size obtained based on a particle size distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer. Moreover, there is no restriction | limiting in particular about purity.

  The shape of the above (C) may be a cubic shape, a spindle shape, a columnar shape, a needle shape, a spherical shape, or an indeterminate shape, but preferably indefinite or spherical.

  The blending amount of the barium sulfate (C) is 10 to 250 parts by weight and preferably 20 to 210 parts by weight with respect to 100 parts by weight of the (A) PPS resin. Less than 10 parts by weight is not preferable because the balance between strength and surface smoothness is poor, and more than 250 parts by weight is not preferable because surface smoothness decreases.

  The barium sulfate (C) is preferably surface-treated, and examples of the treating agent include coating agents, dispersants, modifiers, and the like. Specifically, fatty acids, waxes, nonionic interfaces Examples include activators, epoxy compounds, isocyanate compounds, silane compounds, titanate compounds, phosphorus compounds, aluminum salts such as alumina, silicates such as silicon dioxide, titanium salts such as titanium dioxide, and the like. Furthermore, these can also be used in combination of 2 or more types.

  The component (D) used in the present invention is selected from calcium carbonate and kaolin. These non-fibrous inorganic fillers can be used in combination of two or more. Either calcium carbonate or heavy calcium carbonate may be used, but heavy calcium carbonate is preferably used. Examples of kaolin include calcined kaolin and non-calcined kaolin. It is preferable to use calcined kaolin.

  The average particle diameter of the (D) calcium carbonate is 1 to 15 μm, preferably 1 to 10 μm. When the average particle size is less than 1 μm, the filler is poorly dispersed, the filler is likely to float, and the impact strength is reduced. When it exceeds 15 μm, the surface smoothness is lowered.

  The average particle size of kaolin is 0.5 to 15 μm, preferably 0.7 to 10 μm. When the average particle size is less than 0.5 μm, the impact strength decreases. When it exceeds 15 μm, the surface smoothness is lowered.

  The average particle diameter is a volume-based average particle diameter obtained based on a particle size distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer. Moreover, there is no restriction | limiting in particular about purity.

  The shape of the non-fibrous filler (D) may be a cubic shape, a spindle shape, a columnar shape, a spherical shape, or an indeterminate shape, but is preferably indefinite or spherical.

  The (D) non-fibrous inorganic filler may be surface-treated within a range that does not impair the effects of the present invention. Examples of the treatment agent for performing the surface treatment include a surface modifier and a sizing agent. Specifically, fatty acids, waxes, nonionic surfactants, epoxy compounds, isocyanate compounds, silane compounds, titanate compounds, phosphorus compounds, aluminum salts such as alumina, silicates such as silicon dioxide, Examples thereof include titanium salts such as titanium dioxide.

  The (D) non-fibrous inorganic filler is 0.1 to 150 parts by weight, preferably 0.1 to 100 parts by weight, more preferably 5 to 100 parts by weight of (A) PPS resin. The amount is preferably 80 parts by weight. When it exceeds 150 parts by weight, the surface smoothness tends to be lowered.

  In the present invention, the component (C) and the component (D) are blended with the (A) PPS resin, and the component (B) is blended as an optional component. These (B) to (D) are average particle diameters, averages. In general, the smaller the fiber diameter, the better the surface smoothness. However, even if the average particle diameter and the average fiber diameter are the same, even if (C) component and (D) component or fillers other than these and (B) component are used, they are not necessarily uniformly dispersed, and the filler floats, etc. It tends to occur. In the present invention, a composition excellent in surface smoothness and dimensional accuracy is obtained by selecting a component that is not only small but also has good wettability with (A) PPS resin as a component to be blended with the PPS resin. It is thought that Moreover, when the metal film is formed on the surface by using the component (C) and the component (D) in combination, the surface appearance is excellent, and in particular, the appearance change after heat treatment of the metal film formed can be obtained. .

  You may mix | blend another thermoplastic resin with the resin composition of this invention in the range which does not impair the effect in this invention. Specific examples include polyethylene resin, polypropylene resin, polystyrene resin, ABS resin, polyamide resin, polycarbonate resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyacetal resin, modified polyphenylene ether resin, polysulfone resin, polyallyl sulfone resin, polyketone. Resin, polyetherimide resin, polyarylate resin, liquid crystal polymer, polyethersulfone resin, polyetherketone resin, polythioetherketone resin, polyetheretherketone resin, polyimide resin, polyamideimide resin, polytetrafluoroethylene resin, heat Plastic polyurethane resin, polyamide elastomer, polyester elastomer, polyester resin, polyphenylene ether resin, SAN resin, resin Lil resin, SBS, SEBS, various elastomers, etc., can be blended in a range not impairing the effects of the present invention. Furthermore, these can also be used in combination of 2 or more types.

  Furthermore, it is possible to mix | blend carbon black with the resin composition of this invention in the range which does not impair the effect of this invention. The carbon black can be used in any kind such as for imparting conductivity and for a colorant as long as C (carbon) is a main component, but a channel type and a furnace type used as a colorant are preferable. Carbon black is compounded (added by blending with raw materials during extrusion kneading), masterbatch added (added by blending carbon black master before molding such as injection molding), dry color ( You may use by any addition method of the method of adding by coating carbon black on the surface of a resin composition pellet.

  Further, in the resin composition of the present invention, a coupling agent such as an isocyanate compound, an organic titanate compound, an organic borane compound, and an epoxy compound, a polyalkylene oxide oligomer compound, a thioether, as long as the effects of the present invention are not impaired. Plasticizers such as organic compounds, ester compounds and organic phosphorus compounds, inorganic fine particles, organic phosphorus compounds, crystal nucleating agents such as metal oxides and polyetheretherketone, polyolefins such as polyethylene and polypropylene, waxes of montanic acid, stearin Metal soaps such as lithium acid, aluminum stearate, ethylenediamine / stearic acid / sebacic acid polycondensate, mold release agents such as silicone compounds, anti-coloring agents such as hypophosphite, hindered phenol antioxidants, Phosphorus antioxidant, sulfur oxidation Antioxidants such as stoppers, weathering agents and UV inhibitors (resorcinols, salicylates, benzotriazoles, benzophenones, hindered amines, etc.), heat stabilizers, lubricants (montanic acid and its metal salts, esters, Half ester, stearyl alcohol, stearamide, various bisamides, bisurea, polyethylene wax, etc.), foaming agents, pigments (cadmium sulfide, phthalocyanine, carbon black, metallic pigments, etc.), dyes (nigrosine, etc.), antistatic agents (alkyl sulfate type) Normal addition of anionic antistatic agents, quaternary ammonium salt type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents), flame retardants, etc. Agent can be added

  The method for preparing the resin composition used in the present invention is not particularly limited, but it can be obtained by melt-kneading the components (A), (C), (D) and other raw materials added as necessary. Specifically, the mixture of raw materials is supplied to a generally known melt mixer such as a single or twin screw extruder, Banbury mixer, kneader, or mixin gall, and kneaded at a temperature of 280 to 450 ° C. The method of doing can be given as an example. In addition, there is no particular limitation on the mixing order of the raw materials, a method in which all the raw materials are blended and then melt-kneaded by the above method, a part of the raw materials are blended and then melt-kneaded by the above method, and the remaining raw materials are blended and melted Any method may be used, such as a method of kneading or a method of mixing a part of raw materials and mixing the remaining raw materials using a side feeder during melt-kneading with a single or twin screw extruder. As for the small amount additive component, other components may be kneaded and pelletized by the above-described method and then added before molding and used for molding.

  In the PPS resin composition of the present invention, the loss on heating when heated in air at 320 ° C. for 2 hours is preferably 0.4% by weight or less, and particularly preferably 0.3% by weight or less. Such a PPS resin composition can be obtained by compounding a component (C), a component (D), other optional components, etc., into a base polymer with a PPS resin having a small loss on heating.

  The MFR of the PPS resin composition obtained in the present invention is not particularly limited as long as it can be molded. However, the MFR is 315.5 ° C. for 5 minutes, the load is 2160 g (orifice diameter 2.095 mm, length 8.00 mm). The measured value using a melt indexer under the conditions is preferably 150 g / 10 min or less, more preferably 100 g / 10 min or less from the viewpoint of strength. The lower limit is preferably 15 g / 10 min or more from the viewpoint of fluidity, more preferably 25 g / 10 min or more, and further preferably 30 g / 10 min or more. The MFR of the PPS resin composition depends mainly on the amount of the MPS of the PPS resin to be used, the components (B) to (D), etc., and by using the PPS having a low MFR or the components (B) to (D) Since the MFR tends to decrease as the amount increases, a PPS resin composition having the above range can be obtained by appropriately adjusting these.

  The resin composition of the present invention can be molded by various known injection molding methods such as injection molding, injection compression molding, two-color molding, DSI molding, extrusion molding, and blow molding, and in particular, molding by injection molding. Is preferable in terms of excellent surface smoothness.

  The resin composition of the present invention is excellent in strength, low gas property, and slidability, and is particularly excellent in surface smoothness and strength. Suitable for parts and molded parts for light reflection. For example, exterior parts of automobiles such as fenders and doors, sliding parts such as various gears, pistons, rollers, guides, engine covers of motorcycles and automobiles, cylinder head covers and their integrated parts, electrical component cases, and other containers It is suitable not only for molded articles but also for other structural materials. Specifically, OA equipment parts such as notebook computer housings and printer housings, home appliance housings, covers, intake manifolds, door mirror stays, wheel caps, relay blocks, inhibitor switches, combination switch levers, and other automobiles There are uses for interior and exterior parts. Among them, it is extremely suitable for a light reflecting molded product, particularly a light reflecting molded product having a metal film formed on the surface of the molded product. Examples of products that use the light reflecting molded article include searchlights, spotlights, projector reflectors, OHP reflectors, automobile headlamp reflectors, foglan reflectors, and two-wheel headlamp reflectors. The metal film may be formed directly on the surface of the molded product or may be formed after applying a modifier. However, it is preferable to use the metal film formed directly on the surface of the molded product. The metal film can be formed by a method such as sputtering, vacuum deposition, or ion plating, but sputtering or vacuum deposition is preferable.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by a following example.

  The MFR, heat loss, center line average roughness, impact strength, and surface appearance described in the examples and comparative examples were measured according to the following methods.

[Measurement of MFR of composition]
A value obtained by measuring pellets using a melt indexer under conditions of 315.5 ° C. for 5 minutes and a load of 2160 g (orifice diameter 2.095 mm, length 8.00 mm).

[Measurement of heat loss]
10 g of the resin composition pellets are placed in an aluminum cup and pre-dried in an atmosphere at 150 ° C. for 1 hour. The pellet weight is measured, treated for 2 hours in an atmosphere at 320 ° C., and then the pellet weight is measured again. The weight loss due to heating at 320 ° C. is expressed as a percentage by dividing the weight loss due to the treatment at 320 ° C. by the weight of the pellets before the treatment. The resin composition with less heat loss can be said to be a lower gas, and the surface haze is reduced.

[Measurement of surface roughness (centerline average roughness Ra)]
A mirror-surface square plate (70 mm × 100 mm × 3 mm thickness, film gate) was molded at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. Measure the centerline average roughness Ra specified in JISB0601 with any 10 parts of the mirror surface part of the specular square plate (mold mirror surface roughness 0.03 s) with a surface roughness measuring instrument manufactured by Mitutoyo Corporation. And average. When forming a mirror surface by coating the surface with a metal such as aluminum if it is 35 nm or less, even if the metal is coated by vapor deposition or the like without processing the surface after molding the resin, a level that can be used as a mirror surface, It can be said that it is a preferable level when it is 30 nm or less. The lower the numerical value, the better the surface smoothness.

[Measurement of impact strength]
An impact test piece (1/8 inch (3.2 mm) wide, no notch) according to ASTM D256 was molded at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C., and measured under a temperature condition of 23 ° C. is there. If it is 10 kJ / m ² or more, it can be said that the product strength level has no practical problem, but the higher this value, the better the toughness and the better.

[Surface appearance]
The appearance of the specular square plate used for measuring the surface roughness was visually observed to determine the appearance. Judgment: ◎: cloudiness, good with no filler floating, ○: practical level, but inconspicuous clouding, filler floating, x: cloudy, filler floating, not practical level.

[Metal deposition appearance]
The appearance of a test piece obtained by directly vacuum-depositing aluminum on a specular square plate whose surface appearance was determined was observed. Judgment: A: Cloudy, uneven and inconspicuous and good, ○: Practical level of cloudy and irregular, x: Cloudy, irregular, large and not practical level. The better the appearance, the better the light reflectivity of the product characteristics.

Furthermore, the test piece was heat-treated at 180 ° C. for 2 hours, and the appearance was observed again. The determination was the same as described above.
A sample having a good appearance with no change in appearance before and after the heat treatment was evaluated as ◎. The smaller the appearance change before and after the heat treatment by heat treatment, the better the product characteristics (light reflection) decrease in the actual use environment, and the longer the product life.

[Measurement of molding shrinkage]
Two points each in the flow direction and the right angle direction were measured from the gate of the specular square plate (70 × 100 × 3 mm thickness) used for the surface roughness measurement, and the molding shrinkage was calculated. Nikon universal projector V-24B was used for the measurement. The molding shrinkage rate (%) was calculated by ((die size−molded product size) / die size) × 100. The smaller the molding shrinkage rate, the better the dimensional stability, and the smaller the difference between the molding shrinkage rate in the perpendicular direction and the flow direction, the smaller the change in appearance when heat treating a metal film vapor-deposited molded product, and the better the specularity. Yes. If the value of the molding shrinkage is 1.0% or less, and the difference between the perpendicular direction and the flow direction is 0.15% or less, it can be said that there is no practical problem. The smaller the value, the better.

[Reference example]
(Production of PPS-1)
Into an autoclave equipped with a stirrer, 6.005 kg (25 mol) of sodium sulfide nonahydrate, 0.205 kg (2.5 mol) of sodium acetate and 5 kg of N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) were charged while passing through nitrogen. The temperature was gradually raised to 205 ° C., and 3.6 liters of water was distilled off. Next, after cooling the reaction vessel to 180 ° C., 3.719 kg (25.3 mol) of 1,4-dichlorobenzene and 3.7 kg of NMP were added, sealed under nitrogen, heated to 270 ° C., heated to 270 ° C. Reacted for 2.5 hours. After cooling, the reaction product was washed 5 times with warm water, then heated to 100 ° C., poured into 10 kg of NMP, stirred for about 1 hour, filtered, and washed several times with hot water. This was poured into 25 liters of an acetic acid aqueous solution of pH 4 heated to 90 ° C., and stirred for about 1 hour, filtered, washed with ion-exchanged water at about 90 ° C. until the pH of filtration became 7, It dried under reduced pressure at 80 degreeC for 24 hours, and obtained the PPS resin of MFR600 (g / 10min). The MFR was measured using a melt indexer under conditions of 315.5 ° C., 5 minutes residence, and a load of 5000 g (orifice diameter 2.095 mm, length 8.00 mm). Further, the loss on heating of the PPS resin was 0.5% by weight. In addition, 1 g of PPS resin was put into an aluminum cup, preliminarily dried for 1 hour in an atmosphere of 150 ° C., and then the weight was measured. The weight loss was measured in air at 371 ° C. for 1 hour, and the weight was measured again. The weight loss due to the treatment at 371 ° C. was divided by the weight before the treatment, and expressed as a percentage, which was regarded as the heat loss.

(Production of PPS-2)
An autoclave equipped with a stirrer was charged with 2.98 kg (25 mol) of a 47% aqueous sodium chloride solution, 2.17 kg (26 mol) of 48% sodium hydroxide, 656 g (8 mol) of sodium acetate and 5 kg of NMP, and gradually heated to 205 ° C. Then, 2.8 liters of extracted water containing 2.7 kg of water was removed. To the residual mixture, 3.75 kg (25.5 mol) of 1,4-dichlorobenzene and 2.5 kg of NMP were added and heated at 270 ° C. for 1 hour. The reaction product was washed twice with warm water, dried under reduced pressure at 120 ° C. for 24 hours, and then heat-treated at 230 ° C. for 16 hours to obtain MFR120 (g / 10 min) of PPS-2.
The MFR was measured using a melt indexer under conditions of 315.5 ° C., 5 minutes residence, and a load of 5000 g (orifice diameter 2.095 mm, length 8.00 mm). Further, the loss on heating of the PPS resin was 0.5% by weight. In addition, 1 g of PPS resin was put into an aluminum cup, preliminarily dried for 1 hour in an atmosphere of 150 ° C., and then the weight was measured. The weight loss was measured in air at 371 ° C. for 1 hour, and the weight was measured again. The weight loss due to the treatment at 371 ° C. was divided by the weight before the treatment, and expressed as a percentage, which was regarded as the heat loss.

(Production of PPS-3)
An autoclave equipped with a stirrer was charged with 4.67 kg (25 mol) of an aqueous sodium hydrosulfide solution, 2.00 kg (25 mol) of 50% sodium hydroxide and 8 kg of N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) while stirring. The temperature was gradually raised to 205 ° C., and 4.1 liters of distilled water containing 3.8 kg of water was removed. To the residual mixture, 3.75 kg (25.5 mol) of 1,4-dichlorobenzene and 2 kg of NMP were added and heated at 230 ° C. for 1 hour and further at 260 ° C. for 30 minutes. After cooling, the reaction product was washed 5 times with warm water and dried under reduced pressure at 80 ° C. for 24 hours to obtain an MFR3000 (g / 10 min) PPS resin. The MFR was measured using a melt indexer under conditions of 315.5 ° C., 5 minutes residence, and a load of 5000 g (orifice diameter 2.095 mm, length 8.00 mm). The heat loss of the PPS resin was 0.7% by weight. In addition, 1 g of PPS resin was put into an aluminum cup, preliminarily dried for 1 hour in an atmosphere of 150 ° C., and then the weight was measured. The weight loss was measured in air at 371 ° C. for 1 hour, and the weight was measured again. The weight loss due to the treatment at 371 ° C. was divided by the weight before the treatment, and expressed as a percentage, which was regarded as the heat loss.

(Production of PPS-4)
An autoclave with a stirrer was charged with 6.005 kg (25 mol) of sodium sulfide 9 hydrate, 0.787 kg (9.6 mol) of sodium acetate and 5 kg of NMP, and gradually heated to 205 ° C. through nitrogen, and 3.6 liters of water Distilled. Next, after cooling the reaction vessel to 180 ° C, 3.712 kg (25.25 mol) of 1,4-dichlorobenzene and 2.4 kg of NMP were added, sealed under nitrogen, heated to 270 ° C, heated at 270 ° C. Reacted for 2.5 hours. Next, the mixture was heated to 100 ° C., put into 10 kg of NMP, stirred for about 1 hour, filtered, and further washed with hot water at 80 ° C. for 30 minutes three times. This was filtered, poured into 25 liters of an aqueous solution containing 10.4 g of calcium acetate, and stirred for about 1 hour at 192 ° C. in a sealed autoclave, then filtered, and the pH of the filtration became 7. After washing with ion-exchanged water at about 90 ° C., it was dried under reduced pressure at 80 ° C. for 24 hours to obtain a PPS resin of MFR100 (g / 10 min). The MFR was measured using a melt indexer under conditions of 315.5 ° C., 5 minutes residence, and a load of 5000 g (orifice diameter 2.095 mm, length 8.00 mm). The heat loss of the PPS resin was 0.35% by weight. In addition, 1 g of PPS resin was put into an aluminum cup, preliminarily dried for 1 hour in an atmosphere of 150 ° C., and then the weight was measured. The weight loss was measured in air at 371 ° C. for 1 hour, and the weight was measured again. The weight loss due to the treatment at 371 ° C. was divided by the weight before the treatment, and expressed as a percentage, which was regarded as the heat loss.

[Compounding materials used in Examples and Comparative Examples]
(Fibrous filler)
Wollastonite fiber A: “FPW # 800” average fiber diameter 4.6 μm, L / D = 3 (manufactured by Kinsei Matech)
Wollastonite fiber B: “NYGLOS 4” average fiber diameter 4.0 μm, L / D = 8 (manufactured by NYCO )
Glass fiber: "T-717" average fiber diameter 13 .mu.m (manufactured by Nippon Electric Glass)
In the above, the average fiber diameter of the wollastonite fiber is a volume-based average fiber diameter determined based on a fiber diameter distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer. The average fiber diameter of the potassium titanate fiber and the glass fiber is a weight average fiber diameter measured by an ordinary method using an electron scanning microscope.

(Barium sulfate)
Barium sulfate C1: “B-30” average particle size 0.3 μm, precipitated barium sulfate, alumina-silicon dioxide surface-treated product (manufactured by Sakai Chemical)
Barium sulfate C2: “B-54” average particle size 1.2 μm, precipitated barium sulfate, untreated product (manufactured by Sakai Chemical)
Barium sulfate C3: “BMH-D” average particle size 3.5 μm, precipitated barium sulfate, untreated product (manufactured by Sakai Chemical)
In the above description, the average particle size is a volume-based average particle size obtained based on a particle size distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer.

(Non-fibrous inorganic filler)
Kaolin A: “ASP600” Average particle size 3.0 μm (manufactured by ENGELHARD)
Kaolin B: “Translink 555” Average particle size 0.8 μm (manufactured by ENGELHARD)
Heavy calcium carbonate: “KS1300” average particle size 3.8 μm (manufactured by Dowa Calfine)
Precipitated calcium carbonate: “Brilliant-1500” average particle size 0.2 μm (manufactured by Shiroishi Kogyo)
Talc: “Micron White 5000A” Average particle size 6.7 μm (Made by Hayashi Kasei)
In the above description, the average particle size is a volume-based average particle size obtained based on a particle size distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer.

Examples 1 12 Comparative Examples 1 to 9
After dry blending the PPS (A), fibrous filler (B), barium sulfate (C), and non-fibrous inorganic filler (D) prepared as described above in the proportions shown in Tables 1 to 4 , The mixture was melt-kneaded and pelletized by a screw type twin screw extruder set to an extrusion condition of 350 ° C. The obtained pellets were dried and then subjected to injection molding under the conditions of a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. using an injection molding machine to obtain predetermined test pieces for characteristic evaluation. About the obtained test piece and pellet, MFR, heating loss, centerline surface roughness, impact strength, appearance, and metal vapor deposition appearance were measured by the method described above. The results are shown in Tables 1 to 4.

  The resin composition and the molded body obtained here had surface smoothness and toughness and were highly practical. Further, since the surface smoothness is improved, it is considered that the slidability is also improved. The surface smoothness is such that when a mirror surface is formed by coating aluminum on the surface, the metal can be practically used as a mirror surface even if the metal is coated by vacuum deposition without treating the surface after molding the resin. It was. Further, even when the vapor-deposited molded product was heat-treated, the change in appearance was small and it was highly practical.

Comparative Example 10
Using only barium sulfate having an average particle size of 0.3 μm as a filler, dry blending was carried out in the proportions shown in Table 4 in the same manner as in Examples, and then melt-kneading, pelletizing, molding, and evaluation were performed. The results are shown in Table 4 .

  When only 300 parts by weight of barium sulfate was blended as a filler, the impact strength was low and the appearance was poor and not practical.

Comparative Example 11
Using dry barium sulfate having an average particle size of 3.5 μm and heavy calcium carbonate having an average particle size of 3.8 μm as fillers, dry blending was carried out in the proportions shown in Table 4 in the same manner as in the examples, followed by melt-kneading and pelletizing. Molding and evaluation were performed. The results are shown in Table 4 .

  When barium sulfate having an average particle size of 3.5 μm was used as the filler, the surface roughness and appearance were poor and not practical.

Comparative Example 12
Using a barium sulfate having an average particle diameter of 1.2 μm and a glass fiber having an average fiber diameter of 13 μm as fillers, in the same manner as in the examples, after dry blending in the proportions shown in Table 4 , melt-kneading, pelletizing, molding, and evaluation Went. The results are shown in Table 4 .

  When the component (D) was not blended as the filler, but the component (C) and glass fiber were blended, the surface roughness was poor and the difference in molding shrinkage was large and not practical.

Comparative Example 13
Using calcium carbonate having an average particle size of 3.8 μm as a filler, the mixture was dry blended in the proportions shown in Table 4 in the same manner as in the examples, and then melt-kneaded, pelletized, molded, and evaluated. The results are shown in Table 4 .

  When calcium carbonate was used in place of barium sulfate as a filler, the surface roughness was poor and the impact strength was poor, which was not practical.

Comparative Example 14
Using the barium sulfate having an average particle diameter of 0.3 μm, wollastonite having a fiber diameter of 4.6 μm, and kaolin having an average particle diameter of 0.8 μm as the filler, dry blending was performed at the ratio shown in Table 5 in the same manner as in the example. Thereafter, melt kneading, pelletizing, molding, and evaluation were performed. The results are shown in Table 5 .

  When 300 parts by weight of barium sulfate was used, the loss on heating was large, the impact strength was poor, and it was not at a practical level.

Comparative Example 15
Using PPS-3 as a filler, barium sulfate having an average particle diameter of 1.2 μm was dry blended in the proportions shown in Table 5 in the same manner as in Examples, and then melt-kneaded, pelletized, molded, and evaluated. The results are shown in Table 5 .

  When only PPS-3 and barium sulfate as a filler were blended, the impact strength was low, and the surface heat-treated after metal deposition was fogged, and the appearance was poor and not at a practical level.

Comparative Example 16
Using, as a filler, barium sulfate having an average particle diameter of 1.2 μm and wollastonite A having an average fiber diameter of 4.6 μm, after dry blending in the proportions shown in Table 5 in the same manner as in the examples, melt kneading, pelletizing, Molding and evaluation were performed. The results are shown in Table 5 .

  When the amount of wollastonite fiber was too large as a filler, the surface roughness was poor and the surface smoothness and specularity were inferior and not at a practical level.

Comparative Example 17
Using only barium sulfate having an average particle size of 0.3 μm as a filler, dry blending was performed at the ratio shown in Table 5 in the same manner as in Examples, and then melt-kneading, pelletizing, molding, and evaluation were performed. The results are shown in Table 5 .

  In the case of barium sulfate alone, the surface roughness and appearance were good, but the impact strength was low and the product was not at a practical level.

Comparative Example 18
As a filler, barium sulfate having an average particle diameter of 1.2 μm, wollastonite fiber having a fiber diameter of 4.0 μm and precipitated calcium carbonate having an average particle diameter of 0.2 μm were used in the proportions shown in Table 5 in the same manner as in the Examples. After dry blending, melt kneading, pelletizing, molding, and evaluation were performed. The results are shown in Table 5 .

  When precipitated calcium carbonate having an average particle size of 0.2 μm was used, the filler floated and the appearance was inferior and was not at a practical level.

Comparative Example 19
Using the barium sulfate having an average particle diameter of 1.2 μm and the precipitated calcium carbonate having an average particle diameter of 0.2 μm as the filler, after dry-blending in the proportions shown in Table 5 in the same manner as in the examples, melt kneading, pelletizing, Molding and evaluation were performed. The results are shown in Table 5 .

  When precipitated calcium carbonate having an average particle size of 0.2 μm was used, the impact strength was low, the filler floated, the appearance was inferior, and was not at a practical level.

Comparative Example 20
Using the barium sulfate having an average particle diameter of 1.2 μm, wollastonite having a fiber diameter of 4.0 μm, and talc having an average particle diameter of 6.7 μm as the filler, dry blending was performed at the ratio shown in Table 5 in the same manner as in the example. Thereafter, melt kneading, pelletizing, molding, and evaluation were performed. The results are shown in Table 5 .

  When talc was used instead of the component (D) as the filler, the surface roughness was poor and the filler floated, and the appearance was poor and not at a practical level.

Claims (7)

(A) with respect to the polyphenylene sulfide resin 100 parts by weight, (B) wa Rasutenaito textiles 5-25 parts by weight, (C) 10 to 250 parts by weight of barium sulfate having an average particle size of less than 2.5 [mu] m, (D) an average particle A polyphenylene sulfide resin composition obtained by melt-kneading 0.1 to 150 parts of one or more non-fibrous inorganic fillers selected from calcium carbonate having a diameter of 1 μm to 15 μm and kaolin having an average particle diameter of 0.5 μm to 15 μm. (B) The polyphenylene sulfide resin composition according to claim 1, wherein the average fiber diameter of the wollastonite fiber is 8 μm or less. 3. The polyphenylene sulfide resin composition according to claim 1, wherein the polyphenylene sulfide resin composition has a weight loss by heating of not more than 0.4 wt% at 320 ° C. for 2 hours. Melt flow rate of polyphenylene sulfide resin composition (measured using a melt indexer under conditions of 315.5 ° C., 5 minutes residence, load 2160 g (orifice diameter 2.095 mm, length 8.00 mm)) is 15 g / It is 10 minutes-150 g / 10min, The polyphenylene sulfide resin composition in any one of Claims 1-3. (C) The polyphenylene sulfide resin composition according to any one of claims 1 to 4, wherein barium sulfate is surface-treated. (A) The polyphenylene sulfide resin composition according to any one of claims 1 to 5, wherein the polyphenylene sulfide resin has a heat loss of 1.0% by weight or less at 371 ° C for 1 hour. The polyphenylene sulfide resin composition according to any one of claims 1 to 6, which is used for a light reflecting component by forming a metal film on the surface after forming a molded product.