Inorganic reinforced thermoplastic polyester resin composition and method for producing the same

Abstract

The present invention relates to an inorganic reinforced thermoplastic polyester resin composition, which can obtain a molded product with high rigidity and high strength, less appearance defects and warpage caused by the floating of inorganic reinforcing materials, and a uniform texture appearance without unevenness. The inorganic reinforced thermoplastic polyester resin composition contains a predetermined amount of polybutylene terephthalate resin (A), polyethylene terephthalate resin (B), copolymerized polybutylene terephthalate resin (C), copolymerized polyethylene terephthalate resin (D), polycarbonate resin (E), glass fiber-based reinforcement material (F) and ester exchange inhibitor (G); the glass fiber-based reinforcement material (F) contains at least a predetermined amount of flat cross-section glass fiber (F1) and milled short glass fiber (F2), and the weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the resin composition is 200 to 700 μm, and the melt viscosity is within a specific range.

Description

Technical Field

[0001] The present invention relates to an inorganic reinforced thermoplastic polyester resin composition containing a thermoplastic polyester resin and an inorganic reinforcing material such as glass fiber. Specifically, the present invention relates to an inorganic reinforced thermoplastic polyester resin composition that can obtain a molded product having high rigidity and high strength, less appearance defects caused by the bleed-out of the inorganic reinforcing material, and having a uniform texture appearance without unevenness or a mirror appearance, and further relates to an inorganic reinforced thermoplastic polyester resin composition that has good fluidity and low burr properties even in the molding of long strips and thin-walled molded products. Background Art

[0002] Generally speaking, polyester resins are excellent in mechanical properties, heat resistance, chemical resistance, etc., and are widely used in automobile parts, electrical and / or electronic parts, household sundries, etc. Among them, it is known that the rigidity, strength, and heat resistance of polyester resin compositions reinforced with inorganic reinforcing materials such as glass fibers are greatly improved, and in particular, the rigidity is improved with the addition amount of inorganic reinforcing materials.

[0003] However, if the amount of inorganic reinforcing materials such as glass fibers added is large, the inorganic reinforcing materials such as glass fibers tend to float on the surface of the molded product, which may cause a decrease in surface gloss for molded products that require surface gloss, and may cause poor texture appearance for molded products with matte surfaces.

[0004] In particular, polyester resins such as polybutylene terephthalate, which have a fast crystallization rate, have poor transferability to the mold as they crystallize during molding, making it very difficult to obtain a satisfactory appearance.

[0005] On the other hand, as a method for obtaining a good texture appearance, a method of using isophthalic acid-modified polybutylene terephthalate or polycarbonate resin has been proposed (for example, Patent Documents 1 and 2). However, in Patent Document 1, if the filling amount is increased to obtain high mechanical strength and high rigidity, there is a defect that the appearance is impaired. In Patent Document 2, since a large amount of isophthalic acid-modified polybutylene terephthalate or polycarbonate resin is required, molding stability and molding cycle cannot be satisfied.

[0006] Although Patent Document 3 has been proposed as an improvement to these disadvantages, it is recognized that the following disadvantages still exist: in applications requiring high rigidity, when the amount of reinforcing material is increased to improve rigidity due to insufficient rigidity, the appearance is reduced, and further, the range of molding conditions is very narrow, making it difficult to obtain good products stably.

[0007] In recent years, thin-walled and elongated molded products have made progress. In addition to further requiring high rigidity (flexural modulus greater than 20 GPa), they are also required to have an appearance quality that is equal to or better than before. Patent Document 4 proposes a polyester resin composition that uses flat glass and milled fibers and contains more than 60% by mass of glass fiber reinforcement materials in order to achieve a balance of these qualities. However, there are large differences in mechanical strength, appearance, warpage and other qualities, and stabilizing quality is an important issue.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Publication No. 2007-92005

[0011] Patent Document 2: Japanese Patent Application Publication No. 2008-120925

[0012] Patent Document 3: International Publication No. 2015 / 008831

[0013] Patent Document 4: Japanese Patent Application Publication No. 2017-39878 Summary of the invention

[0014] Problems to be solved by the invention

[0015] The present invention aims to provide an inorganic reinforced thermoplastic polyester resin composition which can obtain a molded product having high rigidity (flexural modulus greater than 20 GPa) and high strength, less appearance defects and warpage deformation caused by the floating of inorganic reinforcing materials, and a uniform texture appearance without unevenness, and which can ensure stable quality even in long-term production with less variation in quality such as mechanical strength, appearance, warpage, etc.

[0016] Means for solving problems

[0017] The present inventors have conducted in-depth studies on the composition and properties of polyester resin compositions in order to solve the above-mentioned problems. As a result, they have found that the cause of quality differences such as mechanical strength, appearance, and warpage during long-term production is related to the length of glass fibers in the polyester resin composition. By setting the fiber length to a specific range, the above-mentioned problems can be achieved, thereby completing the present invention.

[0018] That is, the present invention has the following configurations.

[0019] [1] An inorganic reinforced thermoplastic polyester resin composition comprising 8 to 20 parts by mass of a polybutylene terephthalate resin (A), 1 to 7 parts by mass of a polyethylene terephthalate resin (B), 1 to 12 parts by mass of a copolymerized polybutylene terephthalate resin (C), 5 to 12 parts by mass of a copolymerized polyethylene terephthalate resin (D), 1 to 6 parts by mass of a polycarbonate resin (E), 50 to 70 parts by mass of a glass fiber reinforcement (F), and 0.05 to 2 parts by mass of an ester exchange inhibitor (G), wherein the total amount of the components (A), (B), (C), (D), (E), and (F) is 100 parts by mass;

[0020] The glass fiber-based reinforcing material (F) comprises at least 40 to 55 parts by weight of flat cross-section glass fibers (F1) having a ratio of major diameter to minor diameter (major diameter / minor diameter) of 1.3 to 8, and 5 to 20 parts by weight of milled short glass fibers (F2) having a fiber length of 30 to 150 μm.

[0021] The weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition is 200 to 700 μm,

[0022] The inorganic reinforced thermoplastic polyester resin composition is heated to 270°C and at a shear rate of 10 sec -1 The melt viscosity is 0.6 kPa·s or more and 1.5 kPa·s or less.

[0023] [2] The inorganic reinforced thermoplastic polyester resin composition according to [1] is characterized in that the cooling crystallization temperature (TC2) obtained by differential scanning calorimetry (DSC) is in the range of 160°C ≤ TC2 < 180°C.

[0024] [3] The inorganic reinforced thermoplastic polyester resin composition according to [1] or [2], characterized in that the acid value of the resin component of the inorganic reinforced thermoplastic polyester resin composition is 5 to 50 eq / ton.

[0025] [4] The inorganic reinforced thermoplastic polyester resin composition according to any one of [1] to [3], characterized in that the number average fiber length Ln and the weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition satisfy 1.1≤Lw / Ln≤2.4.

[0026] [5] A method for producing an inorganic reinforced thermoplastic polyester resin composition according to any one of [1] to [4], characterized in that a twin-screw extruder having a plurality of side feeders is used, and the same glass fiber-based reinforcement material (F) is fed separately from the plurality of side feeders.

[0027] Effects of the Invention

[0028] According to the present invention, even if a resin composition is formulated with a large amount of glass fiber-based reinforcement, by setting the curing (crystallization) speed (TC2 is a substitute parameter) of the resin composition in the mold within a specific range, the bubbling of the glass fiber-based reinforcement on the surface of the molded product can be suppressed, thereby greatly improving the appearance of the molded product. Furthermore, by containing a specific glass fiber-based reinforcement within a specific range, a molded product with high strength, high rigidity, and good mirror appearance can be obtained without significantly increasing the molding cycle. In addition, for a molded product with a texture, a molded product with a low gloss (gross) with a black feel and a uniform texture and excellent design can be stably manufactured over a long period of production. DETAILED DESCRIPTION

[0029] Hereinafter, the present invention will be described in detail. In the following description, the content of each component constituting the inorganic reinforced thermoplastic polyester resin composition is expressed in parts by mass, which is the mass part when the total of the components (A), (B), (C), (D), (E) and (F) is 100 parts by mass. The blending amount (mass ratio) of each component used as a raw material in the inorganic reinforced thermoplastic polyester resin composition of the present invention directly becomes the content (mass ratio) of each component in the inorganic reinforced thermoplastic polyester resin composition.

[0030] The polybutylene terephthalate resin (A) in the present invention is a resin that is the main component of all polyester resins in the resin composition of the present invention. It is preferably the most abundant in all polyester resins. There is no particular limitation on the polybutylene terephthalate resin (A), and it is preferred to use a homopolymer composed of terephthalic acid and 1,4-butanediol. In addition, within the range that does not damage the moldability, crystallinity, surface gloss, etc., when the total acid component constituting the polybutylene terephthalate resin (A) is 100 mol% and the total diol component is 100 mol%, other components can be copolymerized to about 5 mol%. As other components, the components used in the copolymerized polybutylene terephthalate resin (C) described below can be listed.

[0031] As for the molecular weight of the polybutylene terephthalate resin (A), the reduced viscosity (0.1 g of the sample is dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6 / 4) and measured at 30°C using an Ubbelohde viscometer) is preferably in the range of 0.5 to 0.7 dl / g, and more preferably in the range of 0.6 to 0.7 dl / g. When it is less than 0.5 dl / g, the toughness of the resin tends to decrease significantly, and burrs tend to be easily generated due to excessive fluidity. On the other hand, when it exceeds 0.7 dl / g, due to the influence of the decreased fluidity of the composition of the present invention, it is difficult to apply uniform pressure to the textured molded product, and therefore it becomes difficult to obtain a good texture appearance (the range of molding conditions becomes narrower).

[0032] The content of the polybutylene terephthalate resin (A) is 8 to 20 parts by mass, preferably 10 to 20 parts by mass, and more preferably 13 to 18 parts by mass. By blending the polybutylene terephthalate resin (A) within this range, various properties can be satisfied.

[0033] The polyethylene terephthalate resin (B) in the present invention is basically a homopolymer of ethylene terephthalate units. In addition, within the range that does not impair various properties, when the total acid component constituting the polyethylene terephthalate resin (B) is 100 mol% and the total diol component is 100 mol%, other components can be copolymerized to about 5 mol%. As other components, the components used in the copolymerized polyethylene terephthalate resin (D) described below can be listed. As other components, diethylene glycol generated by condensation of ethylene glycol during polymerization is also included.

[0034] The molecular weight of the polyethylene terephthalate resin (B) is preferably 0.4 to 1.0 dl / g, more preferably 0.5 to 0.9 dl / g, in a reduced viscosity (0.1 g of a sample is dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6 / 4) and measured at 30°C using an Ubbelohde viscometer. When the reduced viscosity is less than 0.4 dl / g, the strength of the resin tends to decrease, and when the reduced viscosity exceeds 1.0 dl / g, the fluidity of the resin tends to decrease.

[0035] The content of the polyethylene terephthalate resin (B) is 1 to 7 parts by mass, preferably 2 to 7 parts by mass, and more preferably 3 to 6 parts by mass. By blending the polyethylene terephthalate resin (B) within this range, various properties can be satisfied.

[0036] The copolymerized polybutylene terephthalate resin (C) in the present invention is a resin in which 1,4-butanediol accounts for 80 mol% or more of the total acid component constituting the total diol ... When the total acid components constituting the copolymerized polybutylene terephthalate resin (C) are 100 mol%, the copolymerization ratio of isophthalic acid is preferably 20 to 80 mol%, and more preferably 20 to 60 mol%. When the copolymerization ratio is less than 20 mol%, the transferability to the mold is poor and it tends to be difficult to obtain a sufficient appearance. When the copolymerization amount exceeds 80 mol%, the molding cycle is reduced and the demolding property is reduced.

[0037] The molecular weight of the copolymerized polybutylene terephthalate resin (C) may slightly vary depending on the specific copolymer composition, but the reduced viscosity (0.1 g of a sample is dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6 / 4) and measured at 30° C. using an Ubbelohde viscometer) is preferably 0.4 to 1.5 dl / g, and more preferably 0.4 to 1.3 dl / g. When the reduced viscosity is less than 0.4 dl / g, the toughness tends to decrease, and when the reduced viscosity exceeds 1.5 dl / g, the fluidity tends to decrease.

[0038] The content of the copolymerized polybutylene terephthalate resin (C) is 1 to 12 parts by mass, preferably 2 to 10 parts by mass, more preferably 2 to 7 parts by mass, and still more preferably 3 to 6 parts by mass. When the content is less than 1 part by mass, the appearance defects due to the bubbling of glass fibers and poor mold transfer will become conspicuous; when the content exceeds 12 parts by mass, although the appearance of the molded product is good, the molding cycle will be prolonged, which is not preferred.

[0039] The copolymerized polyethylene terephthalate resin (D) in the present invention is a resin in which ethylene glycol accounts for 40 mol% or more when the total acid component constituting the total diol ... As a copolymerization component, 1,4-butanediol is preferably used in an amount of 20 mol% or less.

[0040] The copolymerization ratio of neopentyl glycol is preferably 20 to 60 mol%, more preferably 25 to 50 mol%, based on 100 mol% of the total glycol components constituting the copolymerized polyethylene terephthalate resin (D).

[0041] When the total acid components constituting the copolymerized polyethylene terephthalate resin (D) are taken as 100 mol %, the copolymerization ratio of isophthalic acid is preferably 20 to 60 mol %, more preferably 25 to 50 mol %.

[0042] The molecular weight of the copolymerized polyethylene terephthalate resin (D) may slightly vary depending on the specific copolymer composition, but the reduced viscosity (0.1 g of the sample is dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6 / 4) and measured at 30° C. using an Ubbelohde viscometer) is preferably 0.4 to 1.5 dl / g, and more preferably 0.4 to 1.3 dl / g. When the reduced viscosity is less than 0.4 dl / g, the toughness tends to decrease; when it exceeds 1.5 dl / g, the fluidity tends to decrease.

[0043] The content of the copolymerized polyethylene terephthalate resin (D) is 5 to 12 parts by mass, preferably 6 to 12 parts by mass, and more preferably 7 to 10 parts by mass. When the content is less than 5 parts by mass, the appearance defect caused by the bubbling of glass fibers etc. becomes conspicuous; when the content exceeds 12 parts by mass, although the appearance of the molded product is good, the molding cycle becomes longer, which is not preferred.

[0044] The polycarbonate in the polycarbonate resin (E) used in the present invention can be manufactured by a solvent method, that is, in a solvent such as dichloromethane, in the presence of a known acid acceptor and a molecular weight regulator, by a reaction of a carbonate precursor such as a dihydric phenol and phosgene or an ester exchange reaction of a carbonate precursor such as a dihydric phenol and diphenyl carbonate. Here, as the dihydric phenol preferably used, there are bisphenols, especially 2,2-bis(4-hydroxyphenyl)propane, i.e. bisphenol A. In addition, part or all of bisphenol A can be replaced with other dihydric phenols. As dihydric phenols other than bisphenol A, for example, compounds such as hydroquinone, 4,4'-dihydroxydiphenyl, and bis(4-hydroxyphenyl)alkane, or halogenated bisphenols such as bis(3,5-dibromo-4-hydroxyphenyl)propane and bis(3,5-dichloro-4-hydroxyphenyl)propane can be cited. The polycarbonate can be a homopolymer using one dihydric phenol or a copolymer using two or more. The polycarbonate resin (E) is preferably a resin composed only of polycarbonate. The polycarbonate resin (E) may be a resin copolymerized with a component other than polycarbonate (eg, a polyester component) within a range (20% by mass or less) that does not impair the effects of the present invention.

[0045] The polycarbonate resin (E) used in the present invention preferably has high fluidity, and preferably has a melt volume flow rate (unit: cm 3 The polycarbonate resin (E) preferably has a melt volume flow rate (MWF) of 20 to 100, more preferably 25 to 95, and even more preferably 30 to 90. If a polycarbonate resin (E) having a melt volume flow rate of less than 20 is used, the fluidity is greatly reduced, and there are problems such as reduced strand stability and deteriorated moldability. If the melt volume flow rate exceeds 100, the physical properties are reduced due to the low molecular weight, and there is a problem such as gas generation due to decomposition.

[0046] The content of the polycarbonate resin (E) used in the present invention is 1 to 6 parts by mass, preferably 2 to 5 parts by mass. When the content is less than 1 part by mass, the effect of improving the texture appearance is small; when the content exceeds 6 parts by mass, the molding cycle is easily deteriorated due to the decrease in crystallinity, or the appearance is poor due to the decrease in fluidity, etc., which is not preferred.

[0047] As the glass fiber-based reinforcing material (F) in the present invention, it is preferred to use milled fibers of glass short fibers having an average fiber diameter of about 4 to 20 μm and a cut length of about 30 to 150 μm; and chopped strand-shaped glass fibers having an average fiber diameter of about 1 to 20 μm and cut to a fiber length of about 1 to 20 mm. As the cross-sectional shape of the glass fiber, glass fibers with a circular cross-section and a non-circular cross-section can be used. As the glass fiber with a circular cross-sectional shape, extremely general glass fibers with an average fiber diameter of about 4 to 20 μm and a cut length of about 2 to 6 mm can be used. As the glass fiber with a non-circular cross-sectional shape, glass fibers with an average fiber diameter of about 4 to 20 μm and a cut length of about 2 to 6 mm are included. Glass fibers with a non-circular cross-sectional shape include glass fibers with a cross-section perpendicular to the length direction of the fiber length that is approximately elliptical, approximately oblong, and approximately cocoon-shaped, and the flatness is preferably 1.3 to 8. Here, the flatness refers to the ratio of the major diameter to the minor diameter when a rectangle with the minimum area circumscribed with a cross-section perpendicular to the length direction of the glass fiber is assumed, and the length of the long side of the rectangle is taken as the major diameter and the length of the short side is taken as the minor diameter. The thickness of the glass fiber is not particularly limited, and glass fibers having a short diameter of about 1 to 20 μm and a long diameter of about 2 to 100 μm can be used. These glass fibers may be used alone or in combination of two or more.

[0048] As for the glass fiber-based reinforcing material (F), from the viewpoint of appearance and elastic modulus, a flat cross-section glass fiber (F1) having a ratio of the major diameter to the minor diameter (major diameter / minor diameter) of the fiber cross section of 1.3 to 8 is preferred; from the viewpoint of suppressing glass bubbling, a milled short glass fiber (F2) having a fiber length of 30 to 150 μm is preferred. In the present invention, as the glass fiber-based reinforcing material (F), a flat cross-section glass fiber (F1) and a milled short glass fiber (F2) are used. If necessary, a glass fiber having a circular cross-section shape may also be used.

[0049] The average fiber diameter and average fiber length of the glass fibers can be measured by electron microscope observation.

[0050] These glass fibers can preferably be glass fibers that have been pre-treated with a conventionally known coupling agent such as an organosilane compound, an organotitanium compound, an organoborane compound, or an epoxy compound.

[0051] In the inorganic reinforced thermoplastic polyester resin composition of the present invention, inorganic reinforcing materials other than the above-mentioned glass fibers may be used in combination according to the purpose and within the range that does not impair the characteristics. Specifically, mica, wollastonite, needle-shaped wollastonite, glass flakes, glass beads, etc., which are generally commercially available, may be mentioned. Materials treated with generally known coupling agents may also be used without any problem. When inorganic reinforcing materials other than glass fibers are used in combination, when considering the content of each component of the inorganic reinforced thermoplastic polyester resin composition of the present invention, the total amount of glass fibers and inorganic reinforcing materials other than glass fibers is taken as the content of glass fiber-based reinforcing material (F). When glass fibers and inorganic reinforcing materials other than glass fibers are used in combination, in the glass fiber-based reinforcing material (F), glass fibers are preferably used in an amount of 50% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more. However, as inorganic reinforcing materials, materials that show a strong nucleating agent effect (for example, talc) are not preferred because even a small amount of addition will exceed the range of the cooling crystallization temperature (TC2) of the material specified in the present invention.

[0052] From the viewpoint of rigidity and strength, the content of the glass fiber-based reinforcing material (F) in the present invention is 50 to 70 parts by mass, preferably 60 to 67 parts by mass, and more preferably 62 to 66 parts by mass.

[0053] In this case, as the glass fiber-based reinforcing material (F), at least 40 to 55 parts by mass of flat cross-section glass fibers (F1) having a ratio of the major diameter to the minor diameter of the fiber cross section (major diameter / minor diameter) of 1.3 to 8 and 5 to 20 parts by mass of milled short glass fibers (F2) having a fiber length of 30 to 150 μm are included. The flat cross-section glass fibers (F1) are preferably 42 to 53 parts by mass, more preferably 45 to 50 parts by mass. The milled short glass fibers (F2) are preferably 10 to 18 parts by mass, more preferably 12 to 17 parts by mass.

[0054] In the inorganic reinforced thermoplastic polyester resin composition of the present invention, by using the flat cross-section glass fiber (F1) and the milled short glass fiber (F2) within the above range as the glass fiber-based reinforcement (F), the Charpy impact strength of the molded article obtained by injection molding the inorganic reinforced thermoplastic polyester resin composition can be 20 kJ / m 2 By setting the glass fiber reinforced material (F) to the above-mentioned composition ratio, it is possible to have high mechanical properties and also obtain a good appearance. (Within the range that can maintain a good appearance) The higher the Charpy impact strength, the better, preferably 22 kJ / m 2 above.

[0055] The ester exchange inhibitor (G) used in the present invention, as the name implies, is a stabilizer that prevents the ester exchange reaction of polyester resins. In alloys between polyester resins, no matter how the conditions during manufacturing are optimized, a lot of ester exchange reactions will occur due to the application of thermal history (thermal process). If the degree is very large, the expected properties of the alloy cannot be obtained. In particular, since the ester exchange between polybutylene terephthalate and polycarbonate often occurs, the crystallinity of polybutylene terephthalate is greatly reduced at this time, so it is not preferred. In the present invention, by adding component (G), in particular, the ester exchange reaction between polybutylene terephthalate resin (A) and polycarbonate resin (E) can be prevented, thereby maintaining appropriate crystallinity.

[0056] As the transesterification inhibitor (G), a phosphorus compound having a catalyst deactivating effect on the polyester resin can be preferably used, and for example, "ADEKA STAB AX-71" manufactured by ADEKA Corporation can be used.

[0057] The amount of the transesterification inhibitor (G) used in the present invention is 0.05 to 2 parts by mass, preferably 0.1 to 1 part by mass. When it is less than 0.05 parts by mass, the desired transesterification reaction inhibition performance is often not achieved. On the contrary, even if it is added in excess of 2 parts by mass, not only is the effect hardly noticeable, but it may even become a factor that increases gas, etc.

[0058] Since the inorganic reinforced thermoplastic polyester resin composition of the present invention contains 50 to 70 parts by mass of the glass fiber-based reinforcement (F), the flexural modulus of a molded article obtained by injection molding the inorganic reinforced thermoplastic polyester resin composition can exceed 20 GPa.

[0059] The inorganic reinforced thermoplastic polyester resin composition of the present invention is characterized in that the temperature of the crystallization by cooling determined by differential scanning calorimetry (DSC) is TC2, which is within the range of 160°C or more and less than 180°C. TC2 is the peak top temperature of the crystallization peak of the thermogram obtained by heating to 300°C at a heating rate of 20°C / min under a nitrogen stream, maintaining the temperature for 5 minutes, and then cooling to 100°C at a rate of 10°C / min using a differential scanning calorimeter (DSC). When TC2 is 180°C or more, the crystallization rate of the polyester resin composition becomes faster, and crystallization in the mold occurs too quickly. In particular, in a composition containing a large amount of inorganic reinforcing material, the propagation rate of the injection pressure tends to decrease. Due to insufficient close fit between the injection material and the mold and the influence of crystallization shrinkage, inorganic reinforcing materials such as glass fibers appear on the surface of the molded product, so-called glass floating, etc., resulting in poor appearance of the molded product. In this case, although it is possible to consider setting the mold temperature to a high temperature of 120 to 130°C to delay the solidification of the molded product, this method can improve the surface gloss and appearance of the central part where the injection pressure is high in the mold, but it is difficult to obtain a uniform and good appearance because glass floating and other defects are likely to occur at the end part where the injection pressure is difficult to apply. In addition, since the temperature of the molded product after being taken out of the mold becomes higher, the warping of the molded product will become larger.

[0060] On the contrary, when TC2 is less than 160°C, the crystallization rate becomes too slow, and due to slow crystallization, poor demolding and deformation during extrusion may occur due to adhesion to the mold. In addition, since the resin easily enters deeper into the texture due to the pressure during molding, the resin in the mold is prone to uneven texture depth due to the displacement of the texture during shrinkage and demolding, making it difficult to obtain a good texture appearance. In view of these problems during molding, the inorganic reinforced thermoplastic polyester resin composition of the present invention is adjusted to obtain the most appropriate TC2, thereby obtaining good appearance and moldability even at a mold temperature of 100°C or less.

[0061] TC2 is more preferably 163°C or higher and 177°C or lower, and further preferably 165°C or higher and 175°C or lower.

[0062] Adjustment of TC2 can also be achieved by adjusting the content of polyethylene terephthalate resin (B) and copolymerized polyethylene terephthalate resin (D), but since these components also have a great influence on shrinkage, demolding properties, etc., there are problems such as: even if TC2 is adjusted to the target range by these adjustments, the range of molding conditions that can obtain good appearance becomes narrow; even if good appearance can be obtained, demolding properties deteriorate, etc. With respect to the inorganic reinforced thermoplastic polyester resin composition of the present invention, it has been found that by adjusting TC2 with a specific content of copolymerized polybutylene terephthalate resin (C), a very wide range of molding conditions for good appearance can be obtained, and molding can be performed without negatively affecting other properties. According to the present invention, even for a composition that contains more than 60% by mass of glass fiber-based reinforcement (F) in 100% by mass of the inorganic reinforced thermoplastic polyester resin composition, which is extremely prone to glass floating, good appearance can be obtained in a wide range of molding conditions due to the compounding effect of copolymerized polybutylene terephthalate resin (C).

[0063] Therefore, when the inorganic reinforced thermoplastic polyester resin composition of the present invention is molded at a mold temperature of about 90° C., a good surface appearance can be obtained in a wide range of injection speeds and a wide range of molding conditions. In particular, for a mold subjected to a texture process, a molded product with a uniform appearance having a very jet-black feel and no uneven texture can be obtained.

[0064] Here, the weight average fiber length Lw of the glass fiber reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition of the present invention is 200 to 700 μm, preferably 230 to 700 μm, more preferably 300 to 700 μm, and further preferably 500 to 700 μm. If the weight average fiber length Lw is within the above range, the mechanical strength is not much affected by the fiber length, and a molded product with excellent balance between mechanical properties and fluidity can be obtained. In addition, since the ejection pressure is stable during the manufacturing process and the glass fiber clogging at the front end of the mold is not likely to occur, the strand breakage can be suppressed. On the other hand, when Lw is less than 200 μm, the mechanical strength is reduced, and burrs are generated during molding as the melt viscosity decreases. In addition, when Lw exceeds 700 μm, the production stability is reduced, and the dispersibility of the glass fiber in the resin composition is also reduced, so there are differences in quality such as mechanical strength, appearance, and warping.

[0065] In addition, the number average fiber length Ln and the weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition of the present invention preferably satisfy 1.1≤Lw / Ln≤2.4. Since a predetermined amount of milled short glass fibers (F2) is used, Lw / Ln less than 1.1 means that the fiber length of the flat cross-section glass fibers (F1) becomes shorter than the required length, which is not preferred. On the other hand, when it is greater than 2.4, there is a tendency for the appearance of the molded product to deteriorate. Lw / Ln is more preferably greater than 1.2 and less than 2.3.

[0066] Furthermore, the inorganic reinforced thermoplastic polyester resin composition of the present invention may contain various known additives as required within a range that does not impair the characteristics of the present invention. Examples of known additives include colorants such as pigments, mold release agents, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, modifiers, antistatic agents, flame retardants, dyes, and the like. When the inorganic reinforced thermoplastic polyester resin composition is 100% by mass, these various additives may be contained in an amount up to 5% by mass in total. That is, the total amount of the contents of (A), (B), (C), (D), (E), (F), and (G) in 100% by mass of the inorganic reinforced thermoplastic polyester resin composition is preferably 95 to 100% by mass.

[0067] As the release agent, long-chain fatty acids or their esters and metal salts, amide compounds, polyethylene wax, silicone, polyethylene oxide, etc. can be cited. As long-chain fatty acids, carbon atoms of 12 or more are particularly preferred, such as stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, etc., and part or all of the carboxylic acids can be esterified by monoglycol or polyglycol, or can form metal salts. As amide compounds, ethylene bis terephthalamide, methylene bis stearamide, etc. can be cited. These release agents can be used alone or as a mixture.

[0068] The inorganic reinforced thermoplastic polyester resin composition of the present invention is subjected to a temperature of 270°C and a shear rate of 10 sec. -1 The melt viscosity is 0.6 kPa·s to 1.5 kPa·s, preferably 0.7 kPa·s to 1.4 kPa·s, and more preferably 0.8 kPa·s to 1.3 kPa·s. When the melt viscosity is less than 0.6 kPa·s, injection molding is difficult. On the other hand, when it is greater than 1.3 kPa·s, burrs are easily generated on the molded product. In order to satisfy the melt viscosity, it is important to have the above-mentioned composition ratio.

[0069] The acid value of the resin component contained in the inorganic reinforced polyester resin composition of the present invention is preferably 5 to 50 eq / ton. The acid value is related to the adhesion to the glass fiber and the degree of gas generation during retention. In addition, the acid value affects the toughness of the molded product, so it is very important for thin-walled and long-strip molded products. When the acid value is lower than 5 eq / ton, the toughness decreases due to the decrease in adhesion to the glass fiber, and the dispersibility of the glass fiber in the resin composition decreases, which is likely to cause quality differences. On the other hand, when it is higher than 50 eq / ton, gas is easily generated when the resin is retained at high temperature, and there is a tendency for the appearance of the molded product to deteriorate. The acid value is more preferably 8 to 45 eq / ton.

[0070] As a method for manufacturing the inorganic reinforced thermoplastic polyester resin composition of the present invention, the above-mentioned components and various stabilizers, pigments, etc. as required are mixed and melt-kneaded to produce. The melt-kneading method can use any method known to those skilled in the art, and a single-screw extruder, a twin-screw extruder, a pressure kneading machine, a Banbury mixer, etc. can be used. Among them, a twin-screw extruder is preferably used. As a common melt-kneading condition, the barrel temperature in the twin-screw extruder is 240 to 290° C., and the kneading time is 2 to 15 minutes.

[0071] In addition, only the glass fiber reinforced material (F) or other components as required can be supplied from the side feeder and melt-kneaded. The screw element preferably combines a reverse disk and a kneading disk between the main feeder and the side feeder and applies high shear to melt the polyester resin. It is further preferred to convey the molten polyester resin in the forward direction, merge with the glass fiber reinforced material (F) supplied from the side feeder, and knead in a low shear state. Then, the molten polyester resin composition is extruded from the mold in a low shear state and water-cooled, thereby obtaining a strand of the polyester resin composition. By vacuum drying and molding the obtained polyester resin composition under conditions of, for example, 80°C and 12 hours, a molded product can be obtained.

[0072] As a method for producing the inorganic reinforced thermoplastic polyester resin composition of the present invention, it is preferred to use a twin-screw extruder and feed the same kind of glass fiber-based reinforcement material (F) separately from different feeders.

[0073] In addition, in the present invention, side feeders can be provided at multiple positions. The fiber length of the glass fiber-based reinforcement (F) supplied from the upstream side feeder is shorter than the fiber length of the glass fiber-based reinforcement (F) supplied from the downstream side feeder, but by changing the supply amount of the glass fiber-based reinforcement (F) to each side feeder, it is easy to adjust the fiber length in the composition to within a specified range without changing other extrusion conditions. In addition, compared with the method supplied from the original feeder (main feeder) and 1 side feeder, the above method is easy to control the fiber length distribution, so it is preferred.

[0074] The position of the side feeder for supplying the glass fiber reinforcement (F) can be arbitrarily adjusted according to the target such as the amount of the glass fiber reinforcement (F), the ease of mixing in the resin, the fiber length of the reinforcement, etc. In the production of the inorganic reinforced thermoplastic polyester resin composition of the present invention, it is preferred to set the first side feeder at a position after a quarter of the distance between the main feeder and the die from the main feeder so that the fiber length does not become too short. For example, in a TEM75BS twin-screw extruder with 12 barrels (manufactured by Toshiba Machine Co., Ltd., with 12 barrels, a screw diameter of 75 mm, and L / D=45), it is preferred to set the main feeder in the first barrel, then set the first side feeder in the 4th to 7th barrels, and set the second side feeder in the 8th to 11th barrels, because it is easy to adjust the fiber length. For example, when milled short glass fibers (F2) and flat cross-section glass fibers (F1) are fed from the first side feeder and the second side feeder at a mass ratio of 40 / 60 to 70 / 30, respectively, it is easy to adjust to a suitable fiber length.

[0075] That is, as a method for producing an inorganic reinforced thermoplastic polyester resin composition of the present invention, it is preferred to use a twin-screw extruder having a plurality of side feeders, and feed the same glass fiber-based reinforcing material (F) separately from the plurality of side feeders. In this case, the glass fiber-based reinforcing material (F) is preferably fed only from the plurality of side feeders and not from the main feeder.

[0076] The inorganic reinforced thermoplastic polyester resin composition of the present invention can be made into a molded body by a known molding method. The molding method is not specific, and it can be appropriately used in injection molding, blow molding, extrusion molding, foam molding, special-shaped molding, calendering molding, and other various molding methods. Among them, injection molding is preferred.

[0077] Example

[0078] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples. The measured values ​​described in the examples are measured by the following methods.

[0079] (1) Reduced viscosity of polyester resin

[0080] 0.1 g of the sample was dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6 / 4) and measured at 30°C using an Ubbelohde viscometer. (Unit: dl / g)

[0081] (2) Cooling crystallization temperature (TC2)

[0082] The peak top temperature of the crystallization peak in the thermogram obtained by using a differential scanning calorimeter (DSC) and raising the temperature to 300°C at a heating rate of 20°C / min under a nitrogen flow, maintaining the temperature for 5 minutes, and then lowering the temperature to 100°C at a rate of 10°C / min was determined.

[0083] (3) Mirror appearance of molded products

[0084] When a strip-shaped molded product of 18 mm × 180 mm × 2 mm is molded by injection molding at a barrel temperature of 275°C and a mold temperature of 90°C, the appearance of the molded product A molded within the injection speed range of a filling time of 1 second (molding condition A) and the molded product B molded within the injection speed range of a filling time of 2.2 seconds (molding condition B) are visually observed. In addition, the holding pressure is 75 MPa. If it is "○" or "△", it is a level with no problem.

[0085] ○: No appearance defects due to the floating of glass fibers, etc., good

[0086] △: Some parts (especially the end of the molded product) have a slight appearance defect

[0087] ×: The entire molded product has a poor appearance

[0088] (4) Texture and appearance of molded products

[0089] The texture appearance of the molded product molded under the above-mentioned condition (3) was visually observed. Regarding the texture, a mold with a pear-skin texture with a wrinkle depth of 15 μm was used. If it is "○" or "△", it is a level with almost no problem.

[0090] ○: No surface defects due to misalignment of the texture, good

[0091] △: A small part of the molded product has a poor appearance due to the misalignment of the texture. When observing from a different angle, there is a white part.

[0092] ×: The entire molded product has a poor appearance due to the misalignment of the texture. When observed from a different angle, it looks white.

[0093] (5) Mold release

[0094] When molding is performed under the conditions of (3) above, the demoulding property is judged when the cooling time after the injection process is set to 5 seconds (the entire molding cycle is 17 seconds). If it is "○" or "△", it is a level with almost no problem.

[0095] ○: There is no problem in demolding, and continuous molding is easy

[0096] △: Mold release failure may occur once during several injections, but continuous molding is possible

[0097] ×: Demolding failure occurs every time injection is made, and continuous molding is impossible

[0098] (6) Burr generation

[0099] The maximum value of the burr at the flow end portion generated in the molded article A molded under the above-mentioned condition (3) was measured using a microscope.

[0100] (7) Flexural strength and flexural fracture strain

[0101] The measurement was performed based on ISO 178. The test piece was injection molded under the conditions of a cylinder temperature of 265°C and a mold temperature of 90°C.

[0102] (8) Charpy impact strength

[0103] The measurement was performed based on ISO-179. The test piece was injection molded under the conditions of a cylinder temperature of 265°C and a mold temperature of 90°C.

[0104] (9) Number average fiber length, weight average fiber length

[0105] The residual glass fiber length in the inorganic reinforced thermoplastic polyester resin composition was measured by the following method.

[0106] There are many interferences between glass fibers in the glass fiber high filling material, and the glass fibers are easily damaged during measurement, making it difficult to obtain the correct fiber length. Therefore, in the present invention, in order to accurately measure the glass fiber length, the pellets obtained by melt kneading are heated at a high temperature of 650°C for 2 hours, and the glass fibers are taken out in the form of ash without damaging the glass fibers. The obtained glass fibers are immersed in water and the dispersed glass fibers are taken out onto a glass slide. More than 1,000 glass fibers are randomly selected and observed at 80 times with a digital microscope (KH-7700 manufactured by Hirox Co., Ltd.), and the number average and weight average fiber lengths are obtained, respectively as the number average fiber length and weight average fiber length. In addition, regarding the weight average fiber length (Lw), when the number of fibers having a circumference ratio (π), a fiber length (Li), a density (ρi), and a fiber diameter (ri) is set as (Ni), it can be calculated by the following formula.

[0107] Lw=Σ(Ni×π×ri 2 ×Li 2 ×ρi) / Σ(Ni×π×ri 2 ×Li×ρi)

[0108] When the fiber diameter and density are constant, Lw can be calculated by the following formula.

[0109] Lw=Σ(Ni×Li 2 ) / Σ(Ni×Li)

[0110] (10) Melt viscosity

[0111] The pelletized resin composition was measured using a capillary rheometer Capilograph 1B manufactured by Toyo Seiki Seisaku-sho Co., Ltd. in accordance with ISO 11443 at a furnace temperature of 270°C. At shear speed 10 sec -1 The melt viscosity was measured at 400 °C.

[0112] (11) Acid value

[0113] Acid value of polyester resin;

[0114] 0.5 g of polyester resin was dissolved in 25 ml of benzyl alcohol, and titrated using a benzyl alcohol solution having a sodium hydroxide concentration of 0.01 mol / l. As an indicator, 0.10 g of phenolphthalein dissolved in a mixed solution of 50 ml of ethanol and 50 ml of water was used.

[0115] the acid value of the resin component in the resin composition;

[0116] 0.5 g of the resin composition was dissolved in 25 ml of benzyl alcohol, and titrated using a benzyl alcohol solution having a sodium hydroxide concentration of 0.01 mol / l. As an indicator, 0.10 g of phenolphthalein dissolved in a mixed solution of 50 ml of ethanol and 50 ml of water was used. When measuring the above-mentioned "(9) number average fiber length and weight average fiber length", the mass of the inorganic reinforced thermoplastic polyester resin composition and the mass of the ash content were measured in advance and converted into the mass content of the resin component contained in the resin composition.

[0117] (12) Strand breakage

[0118] The number of times that strand breakage occurred during pellet production when pellet production was performed continuously for 24 hours was evaluated according to the following criteria.

[0119] 0:Less than 10 times

[0120] ×: 10 times or more

[0121] The blending components used in Examples and Comparative Examples are as follows.

[0122] [Polybutylene terephthalate resin (A)]

[0123] (A1) Polybutylene terephthalate: manufactured by Toyobo Co., Ltd., reduced viscosity 0.58 dl / g, acid value 24 eq / ton

[0124] (A2) Polybutylene terephthalate: manufactured by Toyobo Co., Ltd., reduced viscosity 0.58 dl / g, acid value 104 eq / ton

[0125] (A3) Polybutylene terephthalate: manufactured by Toyobo Co., Ltd., reduced viscosity 0.58 dl / g, acid value 4 eq / ton

[0126] (A4) Polybutylene terephthalate: manufactured by Toyobo Co., Ltd., reduced viscosity 0.58 dl / g, acid value 126 eq / ton

[0127] [Polyethylene terephthalate resin (B)]

[0128] (B) Polyethylene terephthalate: manufactured by Toyobo Co., Ltd., reduced viscosity 0.63 dl / g, acid value 20 eq / ton

[0129] [Copolymerized polybutylene terephthalate resin (C)]

[0130] (C1) Copolymer polybutylene terephthalate: a copolymer with a composition ratio of TPA / IPA / / 1,4-BD=70 / 30 / / 100 (mol%), manufactured by Toyobo Co., Ltd., a prototype of Toyobo Vylon (registered trademark), reduced viscosity 0.73 dl / g, acid value 8 eq / ton

[0131] (C2) Copolymer polybutylene terephthalate: a copolymer with a composition ratio of TPA / IPA / / 1,4-BD=45 / 55 / / 100 (mol%), manufactured by Toyobo Co., Ltd., a prototype of Toyobo Vylon (registered trademark), reduced viscosity 0.76 dl / g, acid value 7 eq / ton

[0132] [Copolymerized polyethylene terephthalate resin (D)]

[0133] (D1) Copolymerized polyethylene terephthalate: a copolymer having a composition ratio of TPA / / EG / NPG=100 / / 70 / 30 (mol%), manufactured by Toyobo Co., Ltd., a prototype of Toyobo Vylon (registered trademark), reduced viscosity 0.83 dl / g, acid value 6 eq / ton

[0134] (D2) Copolymerized polyethylene terephthalate: a copolymer having a composition ratio of TPA / IPA / / EG / NPG=50 / 50 / / 50 / 50 (mol%), manufactured by Toyobo Co., Ltd., a prototype of Toyobo Vylon (registered trademark), reduced viscosity 0.53 dl / g, acid value 10 eq / ton

[0135] (The abbreviations represent the components TPA: terephthalic acid, IPA: isophthalic acid, 1,4-BD: 1,4-butanediol, EG: ethylene glycol, and NPG: neopentyl glycol, respectively.)

[0136] [Polycarbonate resin (E)]

[0137] (E1) Polycarbonate: "CALIBRE 301-40" manufactured by Sumika Styron Polycarbonate Co., Ltd., melt volume flow rate (300°C, load 1.2 kg) 40 cm 3 / 10min

[0138] [Glass fiber-based reinforcing material (F)] (The fiber diameter and fiber length are measured values ​​obtained by electron microscope observation)

[0139] (F1) Flat cross-section glass fiber: manufactured by Nittobo Co., Ltd., “CSG3PL830S”, flat cross-section, ratio of major diameter to minor diameter: 2 (minor diameter 10 μm, major diameter 20 μm), average fiber length 3 mm

[0140] (F2) Milled short glass fiber: manufactured by Central Glass Fiber Co., Ltd., “EFH-100-31”, milled fiber (silane treated), average fiber length 100 μm, average fiber diameter 11 μm

[0141] (G) Ester exchange inhibitor: ADEKA STAB AX-71 manufactured by ADEKA

[0142] The inorganic reinforced thermoplastic polyester resin compositions of the examples and comparative examples were weighed according to the mixing ratio (parts by mass) shown in Table 1, and melt-kneaded at a barrel temperature of 270°C and a screw speed of 200 rpm using a TEM75BS twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., with 12 barrels, 75 mm screw diameter, L / D=45) in which a main feeder was provided at the first barrel from the upstream side of the extruder, a first side feeder was provided at the fifth barrel, and a second side feeder was provided at the ninth barrel. Raw materials other than the glass fiber-based reinforcement material (F) were fed into the twin-screw extruder from the feed head (main feeder), and the glass fiber-based reinforcement material (F) was fed from the feeders shown in Table 1, respectively, and the number of strand breakages during continuous production for 24 hours was confirmed. In addition, the pellets of the inorganic reinforced thermoplastic polyester resin composition obtained were dried and then molded into various evaluation samples by an injection molding machine. The evaluation results are shown in Table 1.

[0143] [Table 1]

[0144]

[0145] According to Table 1, in Examples 1 to 10 within the scope of the present invention, in any one of the molding conditions A and molding conditions B, the mirror surface and texture surface of the molded product have an appearance at a level without problems. Among them, in Examples 1 to 8, the acid value and Lw / Ln of the resin component of the resin composition meet the specific range, so in any one of the molding conditions A and molding conditions B, the mirror surface and texture surface of the molded product have a good appearance, and the bending strength and Charpy impact strength are also high. On the other hand, in Comparative Example 1, Lw exceeds the lower limit, so the bending strength and Charpy impact strength become lower, and the melt viscosity is also out of the range, so the amount of burrs also increases. In addition, in Comparative Examples 2 to 5, Lw exceeds the upper limit, so the fluidity of the resin composition is insufficient and the appearance is poor, and the glass fiber is easy to clog the die head during manufacturing, so the ejection is unstable and the strands are easy to break. In particular, in Comparative Example 3 where Lw / Ln exceeded 2.4 and Comparative Example 4 where the crystallization temperature exceeded 180°C, the appearance was significantly deteriorated. In Comparative Example 5 where the crystallization rate was lower than 160°C, the mold releasability was poor.

[0146] Industrial Applicability

[0147] According to the present invention, a molded product having high strength, high rigidity and good surface appearance can be stably obtained within a wide range of molding conditions, thus making a great contribution to the industrial world.

Claims

1. An inorganic reinforced thermoplastic polyester resin composition, comprising 8 to 20 parts by mass of a polybutylene terephthalate resin (A), 1 to 7 parts by mass of a polyethylene terephthalate resin (B), 1 to 12 parts by mass of a copolymerized polybutylene terephthalate resin (C), 5 to 12 parts by mass of a copolymerized polyethylene terephthalate resin (D), 1 to 6 parts by mass of a polycarbonate resin (E), 50 to 70 parts by mass of a glass fiber reinforcement (F), and 0.05 to 2 parts by mass of an ester exchange inhibitor (G), wherein: The total amount of the components (A), (B), (C), (D), (E) and (F) is 100 parts by mass; The copolymerized polybutylene terephthalate resin (C) is a resin in which, when the total acid components are 100 mol % and the total glycol components are 100 mol %, 1,4-butanediol accounts for 80 mol % or more, and the total proportion of terephthalic acid and 1,4-butanediol is 120-180 mol %, and the copolymerized polybutylene terephthalate resin (C) contains 20-80 mol % of at least one selected from the group consisting of isophthalic acid, sebacic acid, adipic acid, trimellitic acid, 2,6-naphthalene dicarboxylic acid, ethylene glycol, diethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, 1,2-propylene glycol, 1,3-propylene glycol and 2-methyl-1,3-propanediol as copolymer components, The copolymerized polyethylene terephthalate resin (D) is a resin in which ethylene glycol accounts for 40 mol% or more when the total acid components are 100 mol% and the total glycol components are 100 mol%, and the total proportion of terephthalic acid and ethylene glycol is 80-180 mol%, and the copolymerized polyethylene terephthalate resin (D) contains 20-120 mol% of at least one selected from the group consisting of isophthalic acid, sebacic acid, adipic acid, trimellitic acid, 2,6-naphthalene dicarboxylic acid, diethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, 1,4-butanediol, 1,2-propylene glycol, 1,3-propylene glycol and 2-methyl-1,3-propanediol as copolymer components, The glass fiber-based reinforcing material (F) comprises at least 40 to 55 parts by weight of flat cross-section glass fibers (F1) having a ratio of major axis to minor axis of the fiber cross section (major axis / minor axis) of 1.3 to 8, and 5 to 20 parts by weight of milled short glass fibers (F2) having a fiber length of 30 to 150 μm. The weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition is 200 to 700 μm, The inorganic reinforced thermoplastic polyester resin composition is heated at 270°C and a shear rate of 10 sec -1 The melt viscosity is 0.6 kPa·s or more and 1.5 kPa·s or less.

2. The inorganic reinforced thermoplastic polyester resin composition according to claim 1, characterized in that: The temperature was raised to 300°C at a rate of 20°C / min under a nitrogen flow using a differential scanning calorimeter (DSC), maintained at this temperature for 5 minutes, and then cooled to 100°C at a rate of 10°C / min. The obtained cooling crystallization temperature TC2 was in the range of 160°C≤TC2<180°C.

3. The inorganic reinforced thermoplastic polyester resin composition according to claim 1 or 2, characterized in that: The acid value of the resin component of the inorganic reinforced thermoplastic polyester resin composition is 5 to 50 eq / ton.

4. The inorganic reinforced thermoplastic polyester resin composition according to claim 1 or 2, characterized in that: The number average fiber length Ln and the weight average fiber length Lw of the glass fiber-based reinforcement material (F) in the inorganic reinforced thermoplastic polyester resin composition satisfy 1.1≤Lw / Ln≤2.

4.

5. A method for producing an inorganic reinforced thermoplastic polyester resin composition according to any one of claims 1 to 4, characterized in that: A twin-screw extruder having a plurality of side feeders is used, and the same glass fiber-based reinforcing material (F) is fed separately from the plurality of side feeders.

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