JP2012211233A - Resin composition, and molded article formed from the resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition that has improved moldability by the improvement of fluidity without impairing the heat resistance and mechanical properties such as the impact resistance and the like of the conventional polyarylate resins and further has improved visibility.SOLUTION: The resin composition includes as constituent components (A) a polyarylate resin, (B) a polycarbonate resin and (C) a methyl methacrylate/styrene copolymer and is characterized in that the mass ratio of the components simultaneously satisfy formulas (I) and (II): formula (I) is (A)/(B)=30/70 to 100/0; and formula (II) is (C)/{(A)+(B)+(C)}=5/100 to 30/100.

Description

  The present invention relates to a resin composition. In particular, the present invention relates to a resin composition containing a polyarylate resin and a methyl methacrylate-styrene copolymer, or containing a polyarylate resin, a polycarbonate resin and a methyl methacrylate-styrene copolymer.

  Polyarylate resins composed of bisphenols and aromatic carboxylic acids are widely known as engineering plastics. Since such polyarylate resin is excellent in heat resistance, mechanical strength, and transparency, the molded body is widely applied in fields such as electric / electronic, automobile, and machine. However, since polyarylate resin has a high melt viscosity, it has a problem that the fluidity during molding is poor and the moldability is not necessarily good.

  As an attempt to improve the moldability while maintaining the mechanical properties and heat resistance of the polyarylate resin, Patent Documents 1 and 2 disclose a resin composition comprising a polyarylate resin and a polycarbonate resin. The resin composition is excellent in mechanical properties and appearance, has little decrease in heat resistance, and further has improved moldability of polyarylate resin. However, in recent years, the weight and size of automobiles and electrical products have been reduced, and the components constituting automobiles and electrical products have also been reduced in size. In such a downsized case, particularly a thin molded product, very good moldability is strongly demanded. However, the resin composition composed of the polyarylate resin and the polycarbonate resin described in Patent Document 1 and Patent Document 2 may not satisfy the required moldability. Furthermore, in the case of patent document 1 and patent document 2, since the fluidity | liquidity of the resin composition obtained is bad, when a fluidity modifier is used in order to improve the fluidity | liquidity, visibility will be impaired, or it may stay. There was a problem that stability was impaired.

  From the current situation as described above, while maintaining the good mechanical properties and heat resistance of the polyarylate resin, the moldability is sufficiently improved, and there are no defects such as lack of visibility seen in conventional fluidity modifiers. A resin composition has been strongly desired.

Japanese Patent Publication No. 50-027061 JP 58-083050 A

  Accordingly, an object of the present invention is to provide a resin composition with improved visibility and improved moldability by improving fluidity without impairing the heat resistance and mechanical properties of conventional polyarylate resins. .

As a result of intensive studies to solve the above problems, the present inventor has blended methyl methacrylate-styrene copolymer (C) with polyarylate resin (A), or polyarylate resin (A) and By blending the methyl methacrylate-styrene copolymer (C) with the polycarbonate resin (B), the visibility is improved and the flow length when the molded body is thinned while maintaining heat resistance and mechanical properties. The present inventors have found that a resin composition with a small decrease in the temperature can be obtained, and have reached the present invention.
That is, the gist of the present invention is as follows.
(1) The polyarylate resin (A), the polycarbonate resin (B), and the methyl methacrylate-styrene copolymer (C) are constituent components, and the mass ratio of each component satisfies the following formulas (I) and (II). A resin composition characterized by the above.
(A) / (B) = 30 / 70-100 / 0 (I)
(C) / {(A) + (B) + (C)} = 5 / 100-30 / 100 (II)
(2) The resin composition according to (1), wherein the copolymerization ratio of methyl methacrylate-styrene copolymer (C) is in the range of methyl methacrylate / styrene = 95/5 to 75/25 in terms of molar ratio. object.
(3) The resin composition according to (1) or (2), wherein the polycarbonate resin (B) has an inherent viscosity of 0.3 to 0.7 dl / g.
(4) A molded article comprising the resin composition according to any one of (1) to (3).

  According to the present invention, by containing a methyl methacrylate-styrene copolymer, while maintaining the heat resistance, mechanical properties, and retention stability of the polyarylate resin to the level required for actual use, It is possible to improve fluidity (moldability). Furthermore, since the flow length is less reduced when the molded body is thinned and visibility is improved, it is very useful. In addition, when a polycarbonate resin is contained, it is possible to improve the mechanical properties of the polyarylate resin and further improve the moldability.

The present invention will be described below.
The resin composition of the present invention is prepared by blending a methyl methacrylate-styrene copolymer (C) with a polyarylate resin (A) or methyl methacrylate- with respect to the polyarylate resin (A) and the polycarbonate resin (B). It is obtained by blending the styrene copolymer (C).

  In the present invention, the polyarylate resin (A) is a polyester composed of an aromatic dicarboxylic acid residue and a bisphenol residue. The polyarylate resin (A) can be produced by a known and common method such as melt polymerization or interfacial polymerization.

  Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and 1,5-naphthalenedicarboxylic acid. , Methyl terephthalic acid, 4,4'-biphenyl dicarboxylic acid, 2,2'-biphenyl dicarboxylic acid, 4,4'-biphenyl ether dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid Examples include acid, 4,4′-diphenylisopropylidenedicarboxylic acid, 1,2-bis (4-carboxyphenoxy) ethane, and 5-sodium sulfoisophthalic acid.

  Among the above, as the aromatic dicarboxylic acid, terephthalic acid and isophthalic acid are preferable, and in view of melt processability and mechanical properties, it is particularly preferable to use a mixture of both. The molar ratio of terephthalic acid and isophthalic acid (terephthalic acid / isophthalic acid) is arbitrarily in the range of 100/0 to 0/100, but when the interfacial polymerization method is used as the production method of the polyarylate resin (A) From the viewpoint of polymerizability, it is preferably 70/30 to 30/70, more preferably 60/40 to 40/60. Among the above terephthalic acid and isophthalic acid molar ratios, it is better to use excess isophthalic acid in order to improve the discoloration resistance to light, especially ultraviolet rays, and in order to improve heat resistance, use excessive terephthalic acid. It is preferable.

  Specific examples of bisphenols include, for example, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, and 2,2-bis. (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl ether, 4 , 4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenylmethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl)- 3,3,5-trimethylcyclohexane (bisphenol TMC), 2 -Phenyl-3,3-bis (4-hydroxyphenyl) phthalimidine (PPPBP) and the like. These compounds may be used alone or in combination of two or more.

  Among these, 2,2-bis (4-hydroxyphenyl) propane is preferably used from the viewpoint of cost performance and polymerizability. From the viewpoint of heat resistance, it is preferable to use bisphenol TMC or PPPBP.

  The inherent viscosity of the polyarylate resin (A) is preferably in the range of 0.3 to 1.0 dl / g, more preferably 0.35 to 0.6 dl / g, and 0.40 to 0 More preferably, it is .55 dl / g. If the inherent viscosity of the polyarylate resin (A) is less than 0.3 dl / g, the molecular weight of the resulting resin composition will be low, which may result in poor mechanical properties and heat resistance. On the other hand, if it exceeds 1.0 dl / g, the melt viscosity becomes high, which may cause discoloration or decrease in fluidity during melt processing. In the present invention, the inherent viscosity is a value measured by dissolving 1.0 g of a sample in 100 ml of 1,1,2,2-tetrachloroethane and preparing a solution at a temperature of 25 ° C. is there.

  The polycarbonate resin (B) in the present invention is composed of bisphenol residues and carbonate residues. Since the polycarbonate resin (B) has a bisphenol residue similar to the polyarylate resin (A), the polycarbonate resin (B) exhibits good compatibility with the polyarylate resin (A), and further molding the polyarylate resin (A). There is an advantage of improving the property, heat resistance and impact resistance. In addition, in this invention, even if it does not mix | blend polycarbonate resin (B), a desired effect may be achieved.

  Examples of bisphenols include 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, and 2,2-bis (3,5-dimethyl). -4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) ) Decane, 1,4-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclododecane, 4,4′-dihydroxydiphenyl ether, 4,4′-dithiodiphenol, 4,4 '-Dihydroxy-3,3'-dichlorodiphenyl ether, 4,4'-dihydroxy-2,5-dihydroxy Phenyl ether and the like.

  Other examples of bisphenols include U.S. Pat. No. 2,999,835, U.S. Pat. No. 3,028,365, U.S. Pat. No. 3,334,154, U.S. Pat. Diphenols described in 131,575 can be used. These may be used alone or in combination of two or more. Among these compounds, it is preferable to use 2,2-bis (4-hydroxyphenyl) propane from the viewpoint of cost performance, and it is preferable to use 2,2-bis (4-hydroxyphenyl) propane alone. Most preferred.

  Examples of the component for introducing a carbonate residue include phosgene and diphenyl carbonate.

  In the present invention, the above inherent viscosity of the polycarbonate resin (B) is preferably 0.3 to 0.7 dl / g, more preferably 0.35 to 0.65 dl / g. If the inherent viscosity of the polycarbonate resin (B) is less than 0.3 dl / g, the resulting resin composition may be inferior in mechanical properties and heat resistance, and conversely if it exceeds 0.7 dl / g, the melt viscosity increases. For this reason, discoloration during melt processing and fluidity deterioration may occur.

  In the present invention, the blending ratio of the polyarylate resin (A) and the polycarbonate resin (B) is (A) / (B) = 30/70 to 100/0 in terms of mass ratio from the viewpoint of heat resistance of the resin composition. It is necessary to be 40/60 to 90/10. When the ratio of the polyarylate resin (A) is less than 30% by mass in the mass ratio, sufficient heat resistance may not be obtained.

  In the present invention, by using the methyl methacrylate-styrene copolymer (C), an effect of improving moldability (fluidity) while maintaining good heat resistance and mechanical properties of the polyarylate resin is exhibited. That is, the methyl methacrylate-styrene copolymer (C) plays a role as a fluidity modifier. Furthermore, there is an advantage that a resin composition free from problems in use such as water absorption and retention deterioration at the time of molding can be obtained with little decrease in flow length when the molded body is thinned. Furthermore, there is an advantage that the visibility of the obtained resin composition is remarkably improved. A resin composition comprising a polyarylate resin or a polyarylate resin and a polycarbonate resin is excellent in transparency but poor in fluidity. Therefore, various fluidity improvers have been used to improve fluidity. However, when a conventional fluidity improver is used, the visibility of the polyarylate resin and the visibility of the resin composition comprising the polyarylate resin and the polycarbonate resin are not only greatly impaired, but also the residence stability is lowered. That is, when a fluidity modifier other than methyl methacrylate-styrene copolymer (C) was used, the visibility, fluidity, and retention stability were insufficient. In order to increase the retention stability, it is effective to lower the molding temperature. However, a decrease in the molding temperature leads to a decrease in fluidity and a problem that the appearance during molding deteriorates. However, in the present invention, since a methyl methacrylate-styrene copolymer is used as a fluidity modifier, the fluidity is improved while improving the visibility (that is, without greatly impairing transparency). It has the remarkable effect of being able to.

  The methyl methacrylate-styrene copolymer (C) used in the present invention can be obtained by a known and usual production method. For example, the production method includes batch type suspension polymerization method, continuous bulk polymerization method, radical polymerization method, solution polymerization method and the like.

  The glass transition temperature measured by the differential scanning calorimetry (DSC method) of the methyl methacrylate-styrene copolymer (C) used in the present invention is 75 from the viewpoint of the balance between heat resistance and fluidity of the resin composition. It is preferable that it is -110 degreeC, and it is more preferable that it is 80-100 degreeC. When the glass transition temperature is less than 75 ° C., the heat resistance of the resulting resin composition may be lowered. On the other hand, when it exceeds 110 ° C., the fluidity of the resin composition may be lowered.

The density measured according to JIS K7112 of the methyl methacrylate-styrene copolymer (C) used in the present invention is 1.10 to 1.22 g / cm ³ from the viewpoint of ensuring compatibility and reducing the weight. Preferably, it is 1.12 to 1.19 g / cm ³ . Further, the melt flow rate (200 ° C., 49 N load) measured according to JIS K7210 of the methyl methacrylate-styrene copolymer (C) used in the present invention is 0.5 from the viewpoint of ensuring compatibility and fluidity. It is preferable that it is -2.5g / 10min, and it is more preferable that it is 0.8-2.0g / 10min.

  As the methyl methacrylate-styrene copolymer (C) used in the present invention, a commercially available product can be suitably used. For example, trade name “Acryster KT-80” manufactured by Denki Kagaku Kogyo Co., Ltd. can be used. .

  The copolymerization ratio of methyl methacrylate and styrene in the structure of the methyl methacrylate-styrene copolymer (C) is preferably in the range of methyl methacrylate / styrene = 95/5 to 75/25 by mass ratio. More preferably, it is within the range of 90/10 to 80/20. When the mass ratio of methyl methacrylate exceeds 95% by mass, sufficient retention stability and moldability may not be obtained in the obtained resin composition. When the mass ratio of styrene exceeds 25% by mass, it is not preferable because appearance defects such as distortion, cracks, breakage, and peeling of the molded body may occur during the high-temperature heat treatment of the molded body.

In the present invention, the mass ratio of the methyl methacrylate-styrene copolymer (C), the polyarylate resin (A), and the polycarbonate resin (B) needs to be in the relationship of the following formula.
(C) / [(A) + (B) + (C)] = 5 / 100-30 / 100 (II)

  The above formula is a blend of methyl methacrylate-styrene copolymer (C) when the total blend amount of polyarylate resin (A), polycarbonate resin (B) and methyl methacrylate-styrene copolymer (C) is 100 parts by mass. Represents a percentage. However, in the present invention, the polycarbonate resin (B) may not be included. In the present invention, [(A) + (B) + (C)] is 100 parts by mass, and the methyl methacrylate-styrene copolymer (C) needs to be 5 to 30 parts by mass. It is preferably 28 parts by mass, and more preferably 7.5 to 25 parts by mass from the viewpoint of moldability. When the blending ratio of the methyl methacrylate-styrene copolymer (C) is less than 5 parts by mass, the moldability is hardly improved based on the fluidity improving effect of the resin composition of the present invention. In addition, the larger the amount of methyl methacrylate-styrene copolymer (C) added, the less the flow length decrease when the molded body is thinned. However, if it exceeds 30 parts by mass, the heat resistance and mechanical properties deteriorate. There is.

  In addition, when using 25 parts by mass or more of methyl methacrylate-styrene copolymer (C) with respect to 100 parts by mass of [(A) + (B) + (C)], mechanical properties of the resin composition, In order not to impair the heat resistance, the blending ratio of the polyarylate resin (A) and the polycarbonate resin (B) is preferably (A) / (B) = 30/70 to 90/10 in terms of mass ratio. / 70 to 80/20 is more preferable. In the case of using 25 parts by mass or more of methyl methacrylate-styrene copolymer (C), if the ratio of the polyarylate resin (A) is less than 30% by mass, it tends to be difficult to obtain sufficient heat resistance, If it exceeds 80% by mass, it tends to be difficult to obtain sufficient mechanical properties. In such a case, if the ratio of the polyarylate resin (A) exceeds 80% by mass, the reason why it becomes difficult to obtain sufficient mechanical properties is not clear, but it is presumed that the following is obtained. That is, when 25 parts by mass or more of the methyl methacrylate-styrene copolymer (C) is used, the fluidity of the resin composition tends to be remarkably improved, while the polyarylate resin (A) and the methyl methacrylate-styrene copolymer are both improved. It is speculated that this is because the difference in melt viscosity from the polymer (C) is increased, and the compatibility of the resin composition tends to be insufficient.

  In the case of using 25 parts by mass or more of methyl methacrylate-styrene copolymer (C) with respect to 100 parts by mass of [(A) + (B) + (C)], the inherent viscosity of the polycarbonate resin (B) is 0.4 to 0.7 dl / g, preferably 0.45 to 0.665 dl / g. In such a case, if the inherent viscosity is less than 0.4 dl / g, it may be difficult to obtain sufficient mechanical properties, and if it exceeds 0.7 dl / g, the fluidity of the resin composition decreases. There is a case.

  In the resin composition of the present invention, in addition to the polyarylate resin (A), the polycarbonate resin (B), and the methyl methacrylate-styrene copolymer (C), within the range not impairing the effects of the present invention, From the viewpoint of stability to light, for example, a phosphite compound, a phenol compound, a benzotriazole compound, a triazine compound, a binderd amine compound, a sulfur compound, or a mixture thereof may be included. Additives other than those described above, for example, antioxidants, ultraviolet absorbers, bluing agents, pigments, flame retardants, mold release agents, antistatic agents, lubricants, organic fillers, as long as the effects of the present invention are not impaired. In addition, an inorganic filler may be included.

  In the present invention, a method in which methyl methacrylate-styrene copolymer (C) is blended with polyarylate resin (A), or methyl methacrylate-styrene copolymer (with respect to polyarylate resin (A) and polycarbonate resin (B) ( The method of blending C) is not particularly limited as long as each component is uniformly dispersed. Specifically, for example, it may be uniformly dry blended using a tumbler or Henschel mixer, then melt-kneaded and extruded, and subjected to a cooling, cutting, and drying step, and pelletized. In melt kneading, a general kneader such as a single screw extruder, a twin screw extruder, a roll kneader, or a Brabender can be used, but from the viewpoint of improving dispersibility, a twin screw extruder should be used. Is preferred.

  The resin composition of the present invention can be molded into various molded products by any method. The molding method is not particularly limited, and an injection molding method, an extrusion molding method, a compression molding method, a blow molding method, or the like can be applied.

  Since the molded body made of the resin composition of the present invention maintains heat resistance and mechanical properties, and the flow length when the molded body is thinned is small, such as a flat-screen TV, personal computer, mobile phone, mobile device, etc. It can be used in casings such as electronic devices and OA devices, various parts, and automotive exterior resin parts such as lamp reflectors. Moreover, it can be suitably used as a cover resin component for various illuminations, indicator lights, warning lights, etc. that require visibility.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to only these examples. Below, the evaluation method implemented by the Example and the comparative example is described.

  In the present specification, the “base resin composition” has the same blending ratio of (A) / (B) with respect to the resin composition consisting of [(A) + (B) + (C)]. And a resin composition not containing (C). In addition, as a base resin composition, the case where the compounding quantity of (B) is 0 mass part is also included. For example, for Examples 1 and 2, Comparative Examples 1 and 2 correspond to the base resin composition, respectively.

(1) Inherent viscosity (dl / g): In accordance with ISO1628-1, an Ubbelohde viscosity tube was used, 1,1,2,2-tetrachloroethane was used as a solvent, and 1 g of a sample was added to 100 ml of the solvent (that is, Measurement was performed at a temperature of 25 ° C. with a concentration of 1 g / dl.

(2) Bar flow flow length (mm): The pellet-shaped resin compositions obtained in Examples and Comparative Examples were dried with hot air at 120 ° C. for 12 hours or more, and then injection molding machine (trade name, manufactured by FANUC) In “S2000i-100B”), the cylinder temperature is set to 320 ° C., the mold temperature is set to 120 ° C., and the flow length of the test piece is measured when the injection pressure is 120 MPa, the injection time is 4 seconds, and the injection speed is 100 mm / second. did. This is an indicator of liquidity. The bar flow test mold with a thickness of 2 mmt, a width of 20 mm, and a length of 980 mm when measuring at a thickness of 2 mmt, and the bar flow test mold with a thickness of 1 mmt, a width of 20 mm, and a length of 330 mm when measuring at a thickness of 1 mmt Was used.

(3) Deflection temperature under load (° C.): It was measured at a load of 1.8 MPa using a test piece having a thickness of 4 mm in accordance with ISO75-1. Further, an annealing treatment was performed before measuring the deflection temperature under load. The annealing treatment was performed for the purpose of removing the internal strain of the molded body, and was allowed to stand in a hot air dryer at 140 ° C. for 3 hours.
In the present invention, a case where the deflection temperature under load is 145 ° C. or higher and the difference from the deflection temperature under load of the base resin composition is within 25 ° C. can be practically used.

(4) Bending elastic modulus (GPa): According to ISO178, a bending test was performed using a test piece having a thickness of 4 mm to obtain a bending elastic modulus.

(5) Tensile elongation at break (%): According to ISO 527-1, a tensile test was performed using a test piece having a thickness of 4 mm to obtain the tensile elongation at break.
In the present invention, those having a tensile elongation at break of 10% or more are assumed to be practically usable.

(6) Charpy impact value (J / m): Measured according to ISO 179-1eA using a test piece with a notch having a thickness of 4 mm.
In the present invention, those having a Charpy impact value of 5 kJ / m ² or more are assumed to be practically usable.

(7) Total light transmittance (%): An injection molding machine (Toshiba Machine Co., Ltd., “EC100N type” was used to mold a 2 mm thick plate. According to ISO 13468-1, a turbidimeter (Nippon Denshoku Industries Co., Ltd.) NDH2000 model) was used, and the total light transmittance was measured under the conditions of light source D65 / viewing angle 2 °.
In the present invention, the total light transmittance is preferably 30% or more, and more preferably 40% or more. In addition, if the total light transmittance was 30% or more, it judged that it had visibility.

(8) Yellow index (%): According to ASTM D1925, a yellow color index (Nippon Denshoku Kogyo Co., Ltd., “SE6000 type”) is used in the reflection method under the conditions of light source D65 / viewing angle 2 °. Hereinafter, it is referred to as a YI value). In addition, the plate obtained by carrying out similarly to (7) was used as a test piece.
In the present invention, the YI value is preferably 20 or less, and more preferably 10 or less.

(8) Water absorption (%): The water absorption after 24 hours was measured in water at 23 ° C. according to ISO62.

(9) Appearance evaluation of molded product during annealing: The plate (molded product) used in (7) was used as a test piece.
The molded product was allowed to stand in a hot air dryer controlled at a constant temperature and annealed for 2 hours, and the appearance of the molded product after the treatment was visually determined. The annealing treatment was similarly performed under each temperature condition of 130 ° C, 140 ° C, and 150 ° C. A molded article with distortion, cracks, breakage or peeling was regarded as abnormal, and judged according to the following evaluation criteria.
(Double-circle): When processed at 150 degreeC, neither the distortion of a molded article, a crack, a fracture | rupture nor peeling was confirmed.
○: When processed at 150 ° C., at least one of distortion, crack, break, and peeling of the molded product was confirmed, but when processed at 140 ° C., distortion, crack, fracture, and peeling of the molded product were confirmed. None were confirmed.
Δ: At least one of distortion, crack, breakage, and peeling of the molded product was confirmed when treated in the 140 ° C test. However, when treated at 130 ° C, the molded product was strained, cracked, broken, and peeled. None were confirmed.
X: When processed by 130 degreeC test, at least any one of the distortion of a molded article, a crack, a fracture | rupture, and peeling was confirmed.

(10) Residence stability test (10) -1. Inherent viscosity retention (%)
Before molding, the inherent viscosity of the resin composition pellets was measured. Next, the resin composition pellets were dried with hot air at 120 ° C. for 12 hours or more, and then molded on an injection molding machine (manufactured by FANUC, trade name “S2000i-100B”) (average length 200 mm, width 53 mm, depth 8 mm average). A wall thickness of 1.5 mm (box shape) was attached, the cylinder temperature was set to 330 ° C., the mold temperature was set to 120 ° C., and injection molding was carried out in a molding cycle of 3.0 minutes. Molding was repeated several shots, and the molded body was collected when the molding was stable. The inherent viscosity of the obtained molded body was measured, and the inherent viscosity retention was calculated from the following formula.
Inherent viscosity retention ratio = (inherent viscosity of molded body) / (inherent viscosity of resin composition pellet before molding) × 100
In addition, it was judged that the inherent viscosity retention rate was larger as the numerical value was larger and the resin composition did not undergo thermal degradation and had residence stability. The inherent viscosity retention is preferably 80% or more, more preferably 90% or more, and most preferably 95% or more.

(10) -2. Appearance during molding (with or without silver)
(10) -1. A molded body was obtained by the method described, and the appearance of the molded body was confirmed. Evaluation was made according to the following criteria.
○: Silver does not occur on the surface of the molded body.
X: Silver is generated on the surface of the molded body.

(10) -3. Molding appearance (yellowish)
(10) -1. A molded body was obtained by the method described, and the appearance of the molded body was confirmed. Evaluation was made according to the following criteria.
○: Even when the molding shot is repeated 10 times, the color of the molded body does not change.
(Triangle | delta): When a shaping | molding shot is repeated 10 times, the color of a molded object changes to yellowishness, and it colors a little.
X: When the molding shot is repeated 10 times, the color of the molded body is remarkably changed, and the yellowness is increased.

(11) Bar flow flow length improvement rate (%): The bar flow flow length improvement rate was measured according to the measurement method of (2) above, and the bar flow flow length improvement rate was calculated by the following formula. This is a value indicating the degree of change in the flow length of the bar flow due to the addition of the methyl methacrylate-styrene copolymer (C).
Bar flow flow length improvement rate (%) = {Bar flow flow length of resin composition consisting of [(A) + (B) + (C)]} / {Bar flow flow length of base resin composition} × 100
In the present invention, those that are 130% or more in the 2 mmt evaluation and 150% or more in the 1 mmt evaluation are assumed to be practically usable.

(12) Bar flow flow length retention when thin (%): The bar flow flow length was measured according to the measurement method of (2) above, and the bar flow flow retention when thin was calculated according to the following formula. This shows a change in thickness dependency during molding by adding the methyl methacrylate-styrene copolymer (C).
Bar flow flow length retention when thin (%) = {1 mmt barflow flow length} / {2 mmt barflow flow length} × 100
The bar flow flow length retention rate at the time of thinness is preferably as the numerical value is large, and indicates that there is little decrease in fluidity when thin.

(13) Fluidity improvement rate In the thin bar flow flow length retention rate of (12), the value obtained by the following formula was defined as the fluidity improvement rate.
Flowability improvement rate (%) = {Bar flow flow length retention rate when thin of resin composition consisting of [(A) + (B) + (C)]}-{Bar flow flow when base resin composition is thin Long retention rate ×× 100
The fluidity improvement rate indicates that the larger the value, the higher the fluidity improvement effect by the fluidity modifier, and it is preferably 5% or more, and more preferably 8% or more.

(14) Tensile rupture elongation retention (%): The tensile rupture elongation was measured according to the measurement method of (5) above, and the tensile rupture elongation retention was calculated according to the following formula. This is a value indicating the degree of change in tensile elongation at break by adding methyl methacrylate-styrene copolymer (C).
Tensile elongation at break (%) = {tensile elongation at break of resin composition of [(A) + (B) + (C)]} / (tensile elongation at break of base resin composition) × 100
In the present invention, it was judged that a material having a tensile elongation at break of 50% or more can be practically used, but it is preferable to hold 65% or more, and more preferable to hold 80% or more. .

(15) Charpy impact value retention ratio (%): The Charpy impact value was measured according to the measurement method of (6) above, and the Charpy impact value retention ratio was calculated by the following formula. This is a value indicating the degree of change in Charpy impact value by adding methyl methacrylate-styrene copolymer (C).
Charpy impact value retention ratio (%) = {Charpy impact value of resin composition of [(A) + (B) + (C)]} / (Charpy impact value of base resin composition) × 100
In the present invention, the Charpy impact value retention rate in the present invention was determined to be practically usable when the Charpy impact value retention rate was 10% or more, but it is preferably 20% or more, preferably 30% It is more preferable to hold the above.

(16) Comprehensive evaluation Excellent heat balance (deflection temperature under load), mechanical properties (tensile elongation at break or Charpy impact value), optical properties (total light transmittance, YI value), and fluidity improvement rate with a good balance. Was evaluated as ◯, and even one having inferior characteristics was evaluated as ×.
In the resin composition of the present invention, it is preferable that both the tensile elongation at break and the Charpy impact value retention are excellent, but even if either one is excellent, the mechanical properties Was judged to be excellent.

The raw materials used in the examples and comparative examples are described below.
・ Polyarylate resin (A)
・ (A-1)
It consists of bisphenol A, terephthalic acid, and isophthalic acid, and has an inherent viscosity of 0.54 dl / g.

・ Polycarbonate resin (B)
・ (B-1)
Product name “Caliber 200-3” manufactured by Sumitomo Dow
The inherent viscosity is 0.645 dl / g.
・ (B-2)
Product name “Caliber 200-30” manufactured by Sumitomo Dow
The inherent viscosity is 0.435 dl / g.

・ Methyl methacrylate-styrene copolymer (C)
・ (C-1)
Product name “Acryster KT-80”, manufactured by Denki Kagaku Kogyo Co., Ltd.
The copolymerization ratio of methyl methacrylate and styrene is methyl methacrylate / styrene = 90/10 in molar ratio.
・ (C-2)
Product name "Cebian MAS 30F", manufactured by Daicel
The copolymerization ratio of methyl methacrylate and styrene is methyl methacrylate / styrene = 60/40 in molar ratio.
・ (C-3)
Product name "Cebian MAS 10F" manufactured by Daicel
The copolymerization ratio of methyl methacrylate and styrene is methyl methacrylate / styrene = 40/60 in molar ratio.

・ Other fluidity modifiers (D)
・ (D-1)
Product name “UMG AXS Resin S900” manufactured by UMG ABS
The copolymerization ratio of methyl methacrylate / acrylonitrile / styrene copolymer is methyl methacrylate / acrylonitrile / styrene = 15/21/64 in molar ratio.
・ (D-2)
Product name “DENKA TH Polymer TH-21” manufactured by Denki Kagaku Kogyo Co., Ltd.
Methyl methacrylate / butadiene / styrene resin (D-3)
Product name "Acrypet VH-001" manufactured by Mitsubishi Rayon Co., Ltd.
Polymethylmethacrylate resin (D-4)
Product name "Toyostyrene GP G210C" manufactured by Toyo Styrene Co., Ltd.
Polystyrene resin (D-5)
Product name “UMG AXS Resin S202N” manufactured by UMG ABS
The copolymerization ratio of acrylonitrile and styrene in terms of molar ratio is acrylonitrile / styrene = 27/73, and the inherent viscosity is 0.668 dl / g.
・ (D-6)
Product name "TOPAS 6015", manufactured by Polyplastics
It is a cycloolefin resin having a glass transition point of 160 ° C., composed of ethylene and norbornene, and containing 79% of norbornene in a mass ratio in the structure.
・ (D-7)
Polyamide 6 having a relative viscosity of 2.5, an amino end group concentration of 62 mol / ton, a melting point of 220 ° C., and no end-blocking agent added during polymerization.
・ (D-8)
Product name "50BWFS", manufactured by Sorusia Japan
Polyamide 66 having a relative viscosity of 2.68, an amino end group concentration of 35 mol / ton, and a melting point of 260 ° C.

Example 1
After the polyarylate resin (A), the polycarbonate resin (B), and the polyamide resin (C) are dry blended and mixed at a blending ratio shown in Table 1 with a total charge of 3 kg, a loss-in-weight continuous quantitative feeder ( KUBOTA's product name “CE-W-1”) is used as the main supply port of a screw-screw 26 mm twin screw extruder (Toshiba Machine Co., Ltd., product name “TEM26SS”) that has one vent part. Supplied. Then, the barrel temperature setting of the extruder is 320 ° C., the degree of vent pressure reduction is −0.099 MPa (gauge pressure), the discharge rate is 20 kg / h, the screw rotation speed is 300 rpm, and the resin composition taken out in a strand form from the die is heated. After cooling and solidifying in a bath, cutting with a pelletizer, and drying with hot air at 120 ° C., resin composition pellets were obtained. In Example 1, polycarbonate resin (B) is not blended.

  Evaluation was carried out based on the evaluation method described above using the obtained resin composition pellets. The results are listed in Table 1. The characteristic values of the base resin used for calculating the bar flow flow length improvement rate, the fluidity improvement rate, the tensile fracture elongation retention rate, the Charpy impact value retention rate, and the like are Comparative Examples 1 to 7 and Comparative Example 19. The values of the properties of the resin compositions (P-1) to (P-8) and (P-8) obtained in (1) were used.

Examples 2-16
Except having the composition shown in Table 1, pellets of the resin composition were obtained in the same manner as in Example 1 and evaluated. The evaluation results are shown in Table 1.

Comparative Examples 1-19
Except having the composition shown in Table 2, pellets of the resin composition were obtained in the same manner as in Example 1 and evaluated. The evaluation results are shown in Table 2. In Comparative Examples 1 to 7 and 19, since the transparency was too good (because it was transparent), the YI value could not be evaluated.

  As is clear from Table 1, the resin compositions obtained in Examples 1 to 9 and 12 to 16 have heat resistance, mechanical properties, thickness dependency during molding, residence stability during molding, and water absorption characteristics. It was excellent. In addition, it had visibility. Furthermore, both the bar flow length and the fluidity improvement rate were excellent, that is, the moldability (fluidity) was excellent.

  In Examples 10 and 11, since the copolymerization ratio of methyl methacrylate and styrene in the methyl methacrylate-styrene copolymer (C) was out of the particularly preferable range of the present invention, the moldability (appearance of the molded product during annealing) was improved. However, it was enough to withstand actual use.

  In Example 16, since the blending amount of the methyl methacrylate-styrene copolymer (C) was out of the particularly preferable range of the present invention, there was room for improvement in mechanical properties, particularly tensile elongation at break. It was enough to withstand actual use.

  In Comparative Examples 1 to 6 and 19, since the methyl methacrylate-styrene copolymer (C) was not blended, the bar flow flow length was a low value, that is, the moldability (fluidity) was inferior.

  In Comparative Example 7, since the blending amount of the polycarbonate resin (B) was excessive, the fluidity was good (that is, about the same as Example 7), but the methyl methacrylate-styrene copolymer (C) The fluidity was not imparted by blending, but the balance between heat resistance and fluidity was poor.

  In Comparative Example 8, since the blending amount of the polyarylate resin (A) was too small, the deflection temperature under load was less than 145 ° C. and the heat resistance was poor.

  In Comparative Example 9, since the blending amount of methyl methacrylate-styrene copolymer (C) was too small, the bar flow flow length improvement rate (1 mmt) and the fluidity improvement rate were low. That is, sufficient moldability (fluidity) was not exhibited.

  In Comparative Example 10, since the amount of methyl methacrylate-styrene copolymer (C) was excessive, there was no problem in moldability (fluidity), bending characteristics, and appearance, but the heat resistance was poor. . In addition, the Charpy impact value and the Charpy impact value retention rate were low, that is, the mechanical strength was poor.

  In Comparative Examples 11 and 12, since a fluidity modifier other than methyl methacrylate-styrene copolymer (C) was used, the inherent viscosity retention was low and the appearance during molding was also deteriorated. That is, the residence stability was insufficient. In addition, the total light transmittance was low, the YI value was high, and the visibility was poor.

  Since Comparative Example 13 used a fluidity modifier other than methyl methacrylate-styrene copolymer (C), the inherent viscosity retention was low, and the appearance during molding was also deteriorated. That is, the residence stability was insufficient. In addition, the total light transmittance was low, and the visibility was poor.

  Since Comparative Example 14 used a fluidity modifier made of only styrene, peeling occurred during the annealing treatment, which was not suitable for actual use.

  In Comparative Example 15, since acrylonitrile-styrene resin was used as the fluidity modifier, the YI value was inferior and the visibility was inferior.

  In Comparative Example 16, since a cycloolefin resin was used as the fluidity modifier, the total light transmittance was lowered and the visibility was poor. In addition, the bar flow flow length (1 mmt) and the flowability improvement rate were low, that is, the moldability (flowability) was lowered. Furthermore, the tensile elongation at break and the tensile elongation at break were low, that is, the mechanical strength was inferior.

  Since Comparative Example 17 and Comparative Example 18 used a polyamide resin as a fluidity modifier, the total light transmittance was lowered and the visibility was inferior. In addition, it was inferior in retention stability and appearance change during molding.

Claims (4)

A polyarylate resin (A), a polycarbonate resin (B), and a methyl methacrylate-styrene copolymer (C) are constituent components, and the mass ratio of each component satisfies the following formulas (I) and (II): Resin composition.
(A) / (B) = 30 / 70-100 / 0 (I)
(C) / {(A) + (B) + (C)} = 5 / 100-30 / 100 (II)   2. The resin composition according to claim 1, wherein the copolymerization ratio of the methyl methacrylate-styrene copolymer (C) is in the range of methyl methacrylate / styrene = 95/5 to 75/25 in terms of molar ratio. .   (B) The inherent viscosity of polycarbonate resin is 0.3-0.7 dl / g, The resin composition of Claim 1 or 2 characterized by the above-mentioned.   The molded object containing the resin composition in any one of Claims 1-3.