JP2001254009A - Molded article composed of polybutylene terephthalate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molded article made of a polybutylene terephthalate resin suitably employed for a molded part of a large casing that requires dimensional stability, molding properties and flame retardance. SOLUTION: The molded part is obtained by injection molding of a flame- retardant polybutylene terephthalate resin composition comprising (A) 100 pts.wt. of a polybutylene terephthalate resin having an intrinsic viscosity of 0.6-1.2 dl/g and a terminal carboxylic group content of 50 meq/kg or less, and incorporated therewith, (B) 5-80 pts.wt. of a polycarbonate resin, (C) 5-80 pts.wt. of an inorganic filler, (D) 1-30 pts.wt. of a halogen-containing flame-retardant, (E) 0.5-15 pts.wt. of an antimony compound comprising as constituting elements antimony pentoxide and an alkali metal oxide and (F) 0.001-5 pts.wt. of a phosphite or a metal phosphate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a molded article comprising a polybutylene terephthalate resin composition having excellent flame retardancy and flow stability during molding. More particularly, the present invention relates to a molded product made of polybutylene terephthalate resin which is suitably used for a large-sized molded product requiring dimensional stability, moldability, and flame retardance, as represented by a battery case for an automobile.

[0002]

2. Description of the Related Art Polybutylene terephthalate resin is a crystalline thermoplastic resin having excellent mechanical properties, electrical properties, other physical and chemical properties, and good workability. Therefore, they are used as engineering plastics in a wide range of applications such as automobiles and electric / electronic parts. Such polybutylene terephthalate resin is used alone in various molded articles, but depending on the field of use, various reinforcing agents, additives, etc. may be blended for the purpose of improving its properties, particularly mechanical properties. Have been done. In general, for applications requiring flame retardancy such as electric / electronic parts, a halogen-based flame retardant and an inorganic flame retardant auxiliary represented by antimony trioxide are used in combination to provide an excellent flame retardant. Those with flammability are used.

[0003] Materials obtained by adding a filler and a flame retardant to these polybutylene terephthalate resins are used in a wide range of fields. Recently, there is an opportunity to use them for large-sized molded products in housings of electric appliances and OA equipment, automotive applications, and the like. Is increasing. In the case of materials used for such large-sized molded products, moldability and flatness (low deformation) are further required.

Regarding the improvement of these characteristics, a method of improving the flatness by using a polycarbonate resin or the like in combination has conventionally been known. However, when a polybutylene terephthalate resin and a polycarbonate resin are used in combination, there is a problem such as inferior melting heat stability. The deterioration of the properties was remarkable, and improvement was required.

As a method for solving these problems, Japanese Patent Application Laid-Open No. Sho 62-64856 proposes a method of blending an antimony compound having a specific structure. According to this method, although the melting heat stability is considerably improved, the effect is not sufficient for a molded article having a large molding machine and a long residence time, such as a large molded article, and the effect is not sufficient. However, the flow stability and discoloration of the obtained molded product were not at a sufficient level, and further improvement was required.

[0006]

DISCLOSURE OF THE INVENTION In view of the above-mentioned problems, the present inventors have developed a flame-retardant material which can be suitably used for large-sized, especially molded housing parts such as housings of electric appliances and OA equipment, battery cases for automobiles and the like. In order to obtain a thermoplastic resin material for a large-sized molded housing part, which has excellent flowability, suppression of discoloration and dimensional stability, the present inventors have conducted intensive studies. as a result,
A composition mainly composed of polybutylene terephthalate resin and blended with polycarbonate resin, inorganic filler, flame retardant, specific antimony compound and phosphorus compound, has excellent flame retardancy and melt stability. They have found that they are extremely useful and have completed the present invention.

That is, the present invention relates to (B) a polycarbonate resin having a viscosity of 0.6 to 1.2 dl / g and a carboxyl group content of not more than 50 meq / kg per 100 parts by weight of a polybutylene terephthalate resin. Parts by weight (C) 5 to 80 parts by weight of inorganic filler (D) 1 to 30 parts by weight of halogen-based flame retardant (E) 0.5 to 15 parts by weight of antimony compound containing antimony pentoxide and alkali metal oxide as components A molded article obtained by injection molding a flame-retardant polybutylene terephthalate resin composition containing 0.001 to 5 parts by weight of a phosphite or a metal phosphate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, the base resin (A) polybutylene terephthalate resin of the present invention is a polybutylene terephthalate obtained by polycondensing terephthalic acid or an ester-forming derivative thereof and an alkylene glycol having 4 carbon atoms or an ester-forming derivative thereof. . In addition, polybutylene terephthalate may be a copolymer containing 70% by weight or more per se.

As dibasic acid components other than terephthalic acid and its lower alcohol esters, aliphatic or aromatic polybasic acids such as isophthalic acid, naphthalenedicarboxylic acid, adipic acid, sebacic acid, trimellitic acid and succinic acid, and esters thereof Formable derivatives and the like, as glycol components other than 1,4-butanediol, include ordinary alkylene glycols such as ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, hexamethylene glycol, neopentyl glycol, and cyclohexane dimethanol. , Lower alkylene glycols such as 1,3-octanediol, bisphenol A, aromatic alcohols such as 4,4'-dihydroxybiphenyl, bisphenol A ethylene oxide 2 mol adduct, bisphenol Alkylene oxide adduct alcohols, such as propylene oxide 3 mol adduct, glycerin, polyhydroxy compound or its ester-forming derivatives such as pentaerythritol, and the like.
In the present invention, any of the polybutylene terephthalates produced by polycondensation using the above compound as a monomer component can be used as the component (A) of the present invention, and they are used alone or in combination of two or more. .

The polybutylene terephthalate resin (A) used in the present invention has an intrinsic viscosity of 0.6 to 1.2 dl / g, preferably 0.65 to 1.1 dl / g, measured at 25 ° C. using O-chlorophenol as a solvent. g range, more preferably
It is important to be in the range of 0.65 to 0.9 dl / g. If the intrinsic viscosity is less than 0.6 dl / g, the amount of gas generated from polybutylene terephthalate such as tetrahydrofuran cannot be reduced sufficiently, resulting in poor appearance during molding and adhesion of deposits. If it exceeds 1.2 dl / g, the fluidity during molding will be poor.

Further, the polybutylene terephthalate resin (A) used in the present invention has a terminal carboxyl group content of 50 meq /
It is also important that the weight is not more than kg, preferably not more than 35 meq / kg. If the amount of terminal carboxyl groups exceeds 50 meq / kg, a decrease in the melting heat stability is observed, and when the large molded product of the present invention is molded, discoloration and a decrease in strength are not preferred. The amount of terminal carboxyl groups was determined by crushing a pulverized sample of polybutylene terephthalate in benzyl alcohol at 215 ° C.
After dissolving for 1 minute, it is determined by titrating with a 0.01N aqueous sodium hydroxide solution and measuring.

In the present invention, a branched polymer belonging to a copolymer as polybutylene terephthalate can also be used. The term "polybutylene terephthalate branched polymer" as used herein refers to a polyester mainly composed of a so-called polybutylene terephthalate or a butylene terephthalate monomer, and branched by adding a polyfunctional compound. The polyfunctional compounds that can be used here include:
There are trimesic acid, trimellitic acid, pyromellitic acid and their alcohol esters, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like.

Next, a polycarbonate resin (B) is added to the composition of the present invention. The (B) polycarbonate resin is added to and blended with the (A) polybutylene terephthalate resin to achieve dimensional stability and low warpage, while suppressing sink marks such as a boss portion of a molded product and reducing hesitation marks. It is small and can make the appearance good, and is an essential component in the present invention.

The polycarbonate resin used for this purpose is prepared by a solvent method, that is, a reaction between a dihydric phenol and a carbonate precursor such as phosgene in a solvent such as methylene chloride in the presence of a known acid acceptor and a molecular weight modifier. Or by a transesterification reaction of a dihydric phenol with a carbonate precursor such as diphenyl carbonate. Bihydric phenols that can be suitably used here include bisphenols, and in particular, 2,2-bis (4-
Hydroxyphenyl) propane, ie bisphenol A
Is preferred. Further, phenol A may be obtained by substituting part or all of phenol A with another dihydric phenol.

Examples of the dihydric phenol other than bisphenol A include hydroquinone, 4,4-dihydroxydiphenyl, bis (4-hydroxyphenyl) alkane,
Compounds such as bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, Or bis (3,5-dibromo-4-hydroxyphenyl) propane, bis (3,5
Halogenated bisphenols such as (-dichloro-4-hydroxyphenyl) propane.
These dihydric phenols may be homopolymers or copolymers of two or more dihydric phenols. Further, the polycarbonate resin used in the present invention may be a thermoplastic random branched polycarbonate obtained by reacting a polyfunctional aromatic with a dihydric phenol and / or a carbonate precursor. The polycarbonate used in the present invention is particularly preferably a highly fluid polycarbonate.

In the present invention, the amount of the polycarbonate (B) is 5 to 80 parts by weight, preferably 15 to 50 parts by weight, based on 100 parts by weight of the polybutylene terephthalate resin (A). (B) If the blending amount of the polycarbonate parts by weight is too small, the obtained molded product does not show sufficient dimensional stability and low warpage, and if it is too large, the molding cycle increases, the releasability deteriorates, and Is not preferred because it causes problems in molding such as a decrease in stability of the melting heat.

Next, the inorganic filler of the component (C) used in the present invention is an essential component for obtaining a molded article having high mechanical strength, impact strength and heat resistance.

Here, as the inorganic filler (C), any of a fibrous filler, a non-fibrous filler (granular, plate-like) or a mixture of both may be used.

Among such fillers, fibrous fillers include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber. And metal fibrous substances such as stainless steel, aluminum, titanium, copper, and brass. In addition, polyamide,
High-melting-point organic fibrous substances such as fluororesins and acrylic resins can be used in the same manner as inorganic fibrous substances. On the other hand, as the particulate filler, carbon black, silica, quartz powder, glass beads, glass powder, calcium silicate, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, titanium oxide, zinc oxide Oxides of metals such as alumina, carbonates of metals such as calcium carbonate and magnesium carbonate, sulfates of metals such as calcium sulfate and barium sulfate, silicon carbide, silicon nitride, boron nitride, and various metal powders. Examples of the plate-like filler include mica, glass flake, various metal foils, and the like.

Of these, glass fibers and carbon fibers are preferred as the fibrous filler. Further, as the non-fibrous filler, an average primary particle size is preferably a granular or plate-like filler having a particle size of 20 μm or less, more preferably glass beads,
Milled fiber, talc, mica and kaolin.

One or more inorganic fillers can be used in combination. The combined use of fibrous fillers, especially glass fibers or carbon fibers, and the above non-fibrous fillers is a preferable combination for obtaining particularly high mechanical strength and dimensional accuracy. Particularly preferably, one or a combination of two or more of glass fiber, glass flake, talc and mica is used.

In using these inorganic fillers,
If necessary, it is desirable to use a sizing agent or a surface treatment agent. As such a sizing agent or a surface treatment agent, for example, a functional compound such as an epoxy compound, an isocyanate compound, a silane compound, a titanate compound or the like is used. These compounds may be used by subjecting the inorganic filler to a convergence treatment or surface treatment in advance, or may be added simultaneously with the preparation of the material.

The amount of the inorganic filler (C) used in the present invention is 5 to 80 parts by weight, preferably 10 to 40 parts by weight, based on 100 parts by weight of the polybutylene terephthalate resin (A). If the amount is too large, the surface of the molded article is deteriorated. If the amount is too small, sufficient mechanical strength cannot be obtained. The amount of the sizing agent or surface treating agent used in combination is 10% by weight or less, preferably 0.05 to 5% by weight, based on the inorganic filler.

The halogen-based flame retardant (D) used in the present invention is an essential component for ensuring the flame retardancy of the resin composition and the molded product. In the present invention, all generally known halogen-based flame retardants for resins are used.
(D) It can be used as a component, and examples thereof include halogen-based flame retardants such as organic chlorine compounds and organic bromine compounds. Organic bromine compounds are particularly preferred, and specifically,
Preferred examples thereof include a brominated aromatic bisimide compound, a brominated aromatic epoxy compound, a brominated polycarbonate, a brominated benzyl acrylate and a polymer thereof, and a brominated polystyrene. These flame retardants can be used alone or in combination of two or more.

The compounding amount of the halogen-based flame retardant (D) is
(A) The amount is 1 to 30 parts by weight, preferably 5 to 20 parts by weight, per 100 parts by weight of the polybutylene terephthalate resin.
If the amount of the flame retardant is too small, sufficient flame retardancy cannot be obtained. If the amount is too large, the mechanical properties and the releasability are lowered, which is not preferable.

Next, the specific antimony compound of the component (E) used in the present invention is an essential component for maintaining the flame retardancy of the obtained molded article. The specific antimony compound used here includes antimony pentoxide (Sb ₂ O ₅ ) and an alkali metal oxide (M ₂ O) as constituent elements,
Preferably whereas antimony pentoxide (Sb ₂ O ₅₎ 0.1 ~0.8
It contains an alkali metal oxide in a molar ratio and has an antimony pentoxide structure. Examples of the metal of the alkali metal oxide include lithium, sodium, potassium, rubidium, and cesium, and sodium and potassium are preferable from the viewpoint of cost, and sodium is particularly preferable.

Such antimony compounds include, for example, (a)
Sodium antimonate is dispersed in water and reacted with a monovalent or divalent inorganic acid 1.5 to 5 times the organic base stoichiometry of 0.5 to 20% by weight of sodium antimonate to form antimony pentoxide gel. (B) The gel is filtered, washed with water, dispersed in water and aged at 50-100 ° C., and (c) an alkali metal hydroxide and / or salt is added thereto, followed by filtration. , Can be prepared by drying and grinding. Drying is possible from room temperature to 500 ° C,
The product obtained by drying at 270 ° C. or less contains 4 to 16% of water as crystallization water. The antimony compound is preferably used in the form of a powder having an average particle diameter of 0.5 to 50 μm.

Further, the antimony compound used in the present invention has a slurry pH of 6 to 6 when dispersed in water.
Those having a range of 10 are preferred, and those having a pH of 7 to 9 are particularly preferred. If the pH of the slurry is less than 6 or more than 10, the decomposition of polybutylene terephthalate is promoted at the time of melting, and the amount of gas generated from the resin may increase.

The amount of the specific antimony compound of the component (E) in the present invention is 0.5 to 15 parts by weight, preferably 1 to 10 parts by weight, particularly preferably 100 parts by weight of the polybutylene terephthalate resin (A). Is 2 to 7 parts by weight.
If the amount of the antimony compound is too small, sufficient flame retardancy cannot be obtained, and if it is too large, mechanical properties such as thermal shock resistance are impaired.

Incidentally, depending on the use of the molded product, it may be required to be "V-0" in the flame retardant category of UL Standard 94. In that case, it is preferable to use a fluorine resin or the like together with the flame retardant. The fluororesin includes homo- or copolymers of fluorine-containing monomers such as tetrafluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, hexafluoropropylene, and perfluoroalkylvinyl ether; the fluorine-containing monomers, ethylene,
Copolymers with copolymerizable monomers such as propylene and (meth) acrylate are included. Examples of such a fluorine-based resin include homopolymers such as polytetrafluoroethylene, polychlorotrifluoroethylene, and polyvinylidene fluoride; tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkyl Vinyl ether copolymer, ethylene-tetrafluoroethylene copolymer, ethylene-
Copolymers such as chlorotrifluoroethylene copolymer are exemplified. These fluororesins can be used alone or in combination of two or more. In addition, these fluororesins,
It can be used in a granular form. The addition amount of the fluororesin
For example, the amount is about 0.1 to 10 parts by weight, preferably about 0.1 to 5 parts by weight, more preferably 0.2 to 1 part by weight, based on 100 parts by weight of the polybutylene terephthalate resin (A).

In the present invention, by molding a resin composition comprising the above components (A) to (E), the resulting molded article has good flame retardancy and excellent dimensional stability. Has low deformability. However, in order to obtain a large molded product continuously, it is necessary to further add (F) a phosphite or a metal phosphate. The (F) phosphite or metal phosphate used here has a high effect of suppressing the transesterification reaction between the (A) polybutylene terephthalate resin and the (B) polycarbonate resin, maintains thermal stability, and melts the resin. Has the effect of suppressing the decomposition of Specific examples of the phosphite include bis (2,6-di-t-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylene phosphite,
Specific examples of the metal phosphate include monobasic calcium phosphate and monobasic sodium phosphate. Of these, a pentaerythritol diphosphite or biphenylene phosphite compound is preferred.

The compounding amount of the phosphite or the metal phosphate of the component (F) is determined according to the amount of the polybutylene terephthalate resin (A)
0.001 to 5 parts by weight with respect to parts by weight, preferably 0.001 to 5 parts by weight.
The amount is from 1 to 2 parts by weight, particularly preferably from 0.002 to 0.8 parts by weight. If the amount of the component (F) is too small, it is difficult to maintain sufficient melt heat stability, and the resulting molded product has poor appearance due to unevenness in fluidity. Also. If the amount is too large, the molded product will be discolored or the influence of the gas derived from the component (F) will be large, making it difficult to obtain a good molded product.

In addition to the phosphite or metal phosphate of the component (F), it is effective to use an antioxidant represented by a hindered phenol for the purpose of further improving the thermal stability. .

Further, in order to impart desired properties according to the purpose, the resin composition of the present invention generally contains known substances added to thermoplastic resins and thermosetting resins, that is, such as ultraviolet absorbers. It is possible to incorporate a stabilizer, an antistatic agent, a coloring agent such as a dye or a pigment, a lubricant, a release agent, a crystallization accelerator, a crystal nucleating agent, and the like.

The composition of the present invention can be easily prepared by known equipment and methods generally used as a conventional method for preparing a resin composition. For example, i) after mixing each component, kneading and extruding with an extruder to prepare pellets and then molding, ii) once preparing pellets having a different composition, mixing a predetermined amount of the pellets and molding. Any method can be used, such as a method of obtaining a molded article having the desired composition after the molding, and iii) a method of directly charging one or more of each component to a molding machine. Mixing and adding a part of the resin component as a fine powder with other components is a preferable method for uniformly blending these components.

[0036]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

The measuring methods for evaluating physical properties shown in the following examples are as follows. (1) Tensile strength and elongation Measured according to ASTM D-638. (2) Melt heat stability After leaving for a certain period of time in the cylinder of the molding machine under the following molding conditions, molding was performed.
The tensile strength was measured according to D-638, and the strength retention with respect to the tensile strength of (1) was determined. (Molding conditions) Molding machine: IS-80EPN manufactured by Toshiba Machine Mold: ASTM D-638 Dumbbell evaluation mold Mold temperature: 70 ° C Cylinder temperature: 260 ° C Injection pressure: P = 74.5MPa Injection speed: V = 1m / min In-machine residence time: 30 min (3) Flow stability The flow length at a thickness of 2 mmt was measured under the following molding conditions.
At the same time, after the first 10 shots were formed, 100 shots were continuously formed, and the flow variation (R = maximum flow length−minimum flow length) was evaluated. (Molding conditions) Molding machine: SG-150U made by Sumitomo Heavy Industries Mold: 2mmt thickness rod flow length evaluation mold Mold temperature: 90 ° C Cylinder temperature: 260 ° C Injection pressure: P = 98.5MPa Injection speed: V = 4m / min ( 4) Warpage Deformation A molded product of 120 mm × 120 mm (thickness 2 mmt) was molded under the following molding conditions, and the amount of warpage was measured. (Molding conditions) Molding machine: SG-150U made by Sumitomo Heavy Industries Mold: 120mm x 120mm x 2mmt Flat mold temperature: 90 ℃ Cylinder temperature: 265-265-265-255-240 ℃ (5) Flammability Underwriters Laboratories Subject 94
In accordance with the method of (UL94), flame retardancy was tested using five test pieces (0.8 mm in thickness). Examples 1 to 10, Comparative Examples 1 to 10 The components (A) to (F) having the compositions shown in Tables 1 and 2 were melt-kneaded with an extruder and pelletized, and then the above characteristics were evaluated. The evaluation results are also shown in Tables 1 and 2.

The details of the components used are as follows. (A) polybutylene terephthalate resin (PBT) (A1) PBT; intrinsic viscosity 0.75 dl / g, terminal carboxyl group amount 45 meq / kg, manufactured by Polyplastics Co., Ltd. (A2) PBT; intrinsic viscosity 0.63 dl / g, Terminal carboxyl group content 25meq / kg, manufactured by Polyplastics Co., Ltd. ・ (B) Polycarbonate resin (B1) polycarbonate; manufactured by Teijin Chemicals Ltd., trade name PALITE L1225 ・ (C) Inorganic filler (C1) glass fiber ( (Diameter 10μm) (C2) glass flakes (thickness about 3μm, central particle size about 300μ
m) ・ (D) Flame retardant (D1) Brominated epoxy resin (BrEP, chemical name: tetrabromobisphenol A-tetrabromobisphenol A diglycidyl ether copolymer, molecular weight about 10,000) ・ (E) Antimony compound (E1) Sb ₂ O ₅ and Na ₂ O (Sb ₂ O ₅ : Na ₂
O: H ₂ O = 1: 0.7: 0.5 mol) (E2) Antimony compound composed of Sb ₂ O ₅ and Na ₂ O (Sb ₂ O ₅ : Na ₂
O: H ₂ O = 1: 0.5: 4.5 mol) (E3) Antimony trioxide (Sb ₂ O ₃ ). (F) Phosphite or metal phosphate (F1) Tetrakis (2,4-di-t-butyl) Phenyl) -4,
4'-biphenylene phosphite (F2) sodium metal phosphate monobasic

[0039]

[Table 1]

[0040]

[Table 2]

As is apparent from the examples, the composition of the present invention has excellent flame retardancy, high heat stability and flow stability, and has good dimensional stability. On the other hand, it is difficult to have good flatness without the addition of the polycarbonate resin (Comparative Examples 1 and 2), and when antimony trioxide is used, the thermal stability and the flow stability are poor, which is not preferable (Comparative Examples). Examples 4, 5). Also, the flow stability is low similarly to the case where no phosphorus-based substance is added, and a molded article that requires high flowability and stable heat stability, such as a large case, is insufficient (Comparative Example 6).

[0042]

As described above, the composition of the present invention has high flame retardancy and excellent dimensional stability, as well as good flow stability and retention heat stability. A molded article molded using a product is used in applications requiring this kind of performance, for example, a battery case of an electric or hybrid vehicle, an ECU (electronic control unit) case, a cover part and a chassis of an electric / OA product, a case part. And the like are suitably used for large-sized molded housing parts.

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Claims (7)

[Claims] (A) 100 parts by weight of a polybutylene terephthalate resin having an intrinsic viscosity of 0.6 to 1.2 dl / g and a terminal carboxyl group content of 50 meq / kg or less, and (B) 5 to 80 parts by weight of a polycarbonate resin. C) 5 to 80 parts by weight of inorganic filler (D) 1 to 30 parts by weight of halogen-based flame retardant (E) 0.5 to 15 parts by weight of antimony compound containing antimony pentoxide and alkali metal oxide as constituent elements (F) Phosphorous acid A molded article obtained by injection molding a flame-retardant polybutylene terephthalate resin composition containing 0.001 to 5 parts by weight of an ester or a metal phosphate. 2. The molded article according to claim 1, wherein the intrinsic viscosity of the polybutylene terephthalate resin (A) is 0.6 to 0.9 dl / g. 3. The molded article according to claim 1, wherein (A) the amount of terminal carboxyl groups of the polybutylene terephthalate resin is 35 meq / kg or less. 4. The molded article according to claim 1, wherein (C) the inorganic filler is one or more selected from glass fiber, glass flake, talc and mica. 5. The antimony compound (E) contains an alkali metal oxide in a molar ratio of 0.1 to 0.8 with respect to antimony pentoxide and has an antimony pentoxide structure.
The molded article according to any one of claims 4 to 4. 6. The molded article according to claim 1, wherein (F) the phosphite is a pentaerythritol diphosphite or biphenylene phosphite. 7. The molded article according to claim 1, wherein the molded article is an automobile battery case or a peripheral molded article thereof.