JP7210345B2 - Polyester resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyester-based resin composition, and more particularly to a polyester-based resin composition excellent in impact resistance, flowability (moldability), and heat resistance.

Polybutylene terephthalate resin is easy to process, has excellent mechanical properties, heat resistance, and other physical and chemical properties. However, in recent years, there is a growing need for large-sized molded parts.

These large products used to be manufactured by assembling a large number of molded parts, but recently, with the improvement of mold design technology and resin molding technology, they are being molded all at once. In addition, there is a tendency for the molded products to be thin, even if they are large. Such molded products have usually been molded with multi-point gates. , one-point gate molding is being applied, and for this purpose, high fluidity is required for the resin material.

To increase the impact resistance of polybutylene terephthalate resin, there are methods such as selecting polybutylene terephthalate with a high molecular weight and alloying it with engineering plastics with excellent impact resistance such as polycarbonate. ) is aggravated.

In particular, household appliances such as IH cookers, hot plates, and electric kettles have heating units such as electric heaters and IH heaters for heating. Furthermore, it is required to have excellent heat resistance. However, the current situation is that the development of materials having excellent heat resistance in addition to impact resistance and fluidity has been difficult.

In Patent Document 1, as a method for improving impact resistance while avoiding a decrease in fluidity of polybutylene terephthalate resin, a styrene-maleic anhydride copolymer and a polyalkylene oxide are used in addition to an epoxy group-containing ethylene copolymer. A method of melt-kneading a reaction product with a monoalkyl ether has been proposed. However, the liquidity in this proposal is not necessarily sufficient.
As mentioned above, especially recently, even when injection molding large-sized and complicated-shaped molded products, injection molding has been carried out using a single-point gate, and more excellent fluidity is required. Even in such a case, it is required to satisfy impact resistance, fluidity (moldability) and heat resistance at the same time.

JP-A-8-104799

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a polyester-based resin composition that achieves both high impact resistance and high fluidity (moldability) and is also excellent in heat resistance. .

The inventors of the present invention have made intensive studies to solve the above problems, and as a result, found that the above problems can be solved by incorporating two types of special elastomer components in combination into polybutylene terephthalate resin and polycarbonate resin. , completed the present invention.
The present invention relates to the following polyester resin composition.

[1] For a total of 100 parts by mass of (A) and (B) containing 60 to 90 parts by mass of (A) polybutylene terephthalate resin and (B) 10 to 40 parts by mass of polycarbonate resin,
(C) 1 to 20 parts by mass of a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic ester, and (D) a copolymer of an α-olefin and a (meth)acrylic ester [however, (C) Copolymers of α-olefins, unsaturated glycidyl compounds and (meth)acrylic acid esters are excluded. ] A polyester resin composition characterized by containing 1 to 20 parts by mass.
[2] The total content of (C) the copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester and (D) the copolymer of α-olefin and (meth)acrylic acid ester is The polyester resin composition according to the above [1], which is 3 to 30 parts by mass with respect to a total of 100 parts by mass of (A) and (B).
[3] (C) The content of the copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester is 5 to 42% by mass with respect to the total 100% by mass of (C) and (D). The polyester resin composition according to the above [1] or [2].
[4] The polyester resin composition according to any one of [1] to [3] above, wherein (D) the copolymer of α-olefin and (meth)acrylic acid ester has an MFR of 35 to 350 g/10 min.

In the polyester-based resin composition of the present invention, (C) α-olefin-unsaturated glycidyl compound-(meth)acrylic acid is added to a system containing both (A) polybutylene terephthalate-based resin and (B) polycarbonate resin. High impact resistance and high fluidity (moldability) are achieved for the first time by combining and compounding two types of elastomers, ester copolymer and (D) α-olefin-(meth)acrylic acid ester copolymer. can be achieved in a well-balanced manner, and the effect of being excellent in heat resistance can be exhibited.
Therefore, the polyester-based resin composition of the present invention can be applied to a wide range of fields such as the electric/electronic field (particularly the field of home electric appliances), the field for vehicles (particularly the field of automobiles), and the field of building materials. In particular, the polyester-based resin composition of the present invention has high impact resistance and heat resistance even if it has a complicated shape, and is easy to mold, so it is useful for molded articles for various home electric appliances.

The polyester-based resin composition of the present invention is
(A) containing 60 to 90 parts by mass of polybutylene terephthalate resin and (B) 10 to 40 parts by mass of polycarbonate resin for a total of 100 parts by mass of (A) and (B),
(C) 1 to 20 parts by mass of a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic ester, and (D) a copolymer of an α-olefin and a (meth)acrylic ester [however, (C) Copolymers of α-olefins, unsaturated glycidyl compounds and (meth)acrylic acid esters are excluded. ] is characterized by containing 1 to 20 parts by mass.

The contents of the present invention will be described in detail below.
The description of each constituent element described below may be made based on representative embodiments and specific examples of the present invention, but the present invention is interpreted as being limited to such embodiments and specific examples. not a thing In the specification of the present application, the term "~" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit.

[(A) Polybutylene terephthalate resin]
As the (A) polybutylene terephthalate resin (hereinafter sometimes abbreviated as "PBT resin"), which is the main component constituting the polyester resin composition of the present invention, a terephthalic acid unit and 1,4-butane A polymer having a structure in which diol units are ester-bonded is shown. That is, in addition to the polybutylene terephthalate resin (homopolymer), a polybutylene terephthalate copolymer containing other copolymerization components other than the terephthalic acid unit and the 1,4-butanediol unit, or a homopolymer and the copolymer including mixtures with

The PBT resin may contain dicarboxylic acid units other than terephthalic acid. Specific examples of other dicarboxylic acids include isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, and 2,5-naphthalenedicarboxylic acid. , 2,6-naphthalenedicarboxylic acid, biphenyl-2,2′-dicarboxylic acid, biphenyl-3,3′-dicarboxylic acid, biphenyl-4,4′-dicarboxylic acid, bis(4,4′-carboxyphenyl)methane , anthracene dicarboxylic acid, aromatic dicarboxylic acids such as 4,4′-diphenyl ether dicarboxylic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 4,4′-dicyclohexyl dicarboxylic acid, and adipic acid , sebacic acid, azelaic acid, dimer acid and other aliphatic dicarboxylic acids.

The diol unit may contain other diol units in addition to 1,4-butanediol. Specific examples of other diol units include aliphatic or alicyclic diols having 2 to 20 carbon atoms. and bisphenol derivatives. Specific examples include ethylene glycol, propylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, cyclohexanedimethanol, 4,4′-dicyclohexylhydroxymethane, ,4'-dicyclohexylhydroxypropane, ethylene oxide-added diol of bisphenol A, and the like. Furthermore, triols such as glycerin and trimethylolpropane are also included.

The PBT resin is preferably a polybutylene terephthalate homopolymer obtained by polycondensation of terephthalic acid and 1,4-butanediol, and as the carboxylic acid unit, one or more dicarboxylic acids other than the above terephthalic acid and/or A polybutylene terephthalate copolymer containing at least one diol other than the 1,4-butanediol as a diol unit may be used. In the PBT resin, the proportion of terephthalic acid in dicarboxylic acid units is preferably 70 mol % or more, more preferably 90 mol % or more, from the viewpoint of mechanical properties and heat resistance. Similarly, the proportion of 1,4-butanediol in diol units is preferably 70 mol % or more, more preferably 90 mol % or more.

In addition to the above bifunctional monomers, trifunctional monomers such as trimellitic acid, trimesic acid, pyromellitic acid, pentaerythritol, and trimethylolpropane for introducing a branched structure, and fatty acids for molecular weight adjustment. A small amount of monofunctional compound can also be used together.

The PBT resin is produced by melt-polymerizing a dicarboxylic acid component or an ester derivative thereof mainly composed of terephthalic acid and a diol component mainly composed of 1,4-butanediol in a batch or continuous manner. can be done. Further, after producing a low-molecular-weight polybutylene terephthalate resin by melt polymerization, the degree of polymerization (or molecular weight) can be increased to a desired value by solid-phase polymerization under a nitrogen stream or under reduced pressure.

The PBT resin is preferably produced by continuous melt polycondensation of a dicarboxylic acid component mainly composed of terephthalic acid and a diol component mainly composed of 1,4-butanediol.

Catalysts used in carrying out the esterification reaction may be those conventionally known, and examples thereof include titanium compounds, tin compounds, magnesium compounds, calcium compounds, and the like. Particularly suitable among these are titanium compounds. Specific examples of the titanium compound as the esterification catalyst include titanium alcoholates such as tetramethyl titanate, tetraisopropyl titanate and tetrabutyl titanate, and titanium phenolates such as tetraphenyl titanate.

The PBT resin may be a polybutylene terephthalate resin modified by copolymerization, and a specific preferred copolymer thereof is copolymerized with polyalkylene glycols (especially polytetramethylene glycol (PTMG)). Polyester ether resins, dimer acid-copolymerized polybutylene terephthalate resins, particularly isophthalic acid-copolymerized polybutylene terephthalate resins can be mentioned. In addition, these copolymers refer to those having a copolymerization amount of 1 mol % or more and less than 50 mol % in all segments of the PBT resin. Among them, the copolymerization amount is preferably 2 to 50 mol %, more preferably 3 to 40 mol %, particularly preferably 5 to 20 mol %.

When these copolymers and homopolymers are mixed and used, the preferable content of the copolymer is 50% by mass or less, or even 5% by mass in 100% by mass of the total amount of (A) polybutylene terephthalate resin. to 30% by weight, especially 10 to 20% by weight.

The intrinsic viscosity ([η]) of the PBT resin is preferably high in order to obtain high impact resistance, specifically, preferably 0.7 dl/g or more, and 0.75 dl/g or more is more preferable, and that of 0.80 dl/g or more is even more preferable. In addition, if the intrinsic viscosity is too high, the fluidity of the resin when melted deteriorates, which may impair the moldability in injection molding. is preferably 1.3 dl/g or less, more preferably 1.2 dl/g or less, and particularly preferably 1 dl/g or less.
The intrinsic viscosity is measured at 30° C. in a 1:1 (mass ratio) mixed solvent of tetrachloroethane and phenol.

The content of (A) polybutylene terephthalate resin is based on a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin, and (A) PBT resin is 60 to 90 parts by mass. is preferably 67 parts by mass or more, more preferably 74 parts by mass or more, and still more preferably 80 parts by mass or more. Moreover, as an upper limit, it is 85 mass parts or less, More preferably, it is 80 mass parts or less. When the above upper limit is exceeded, the effect of improving the impact resistance and toughness of the polyester-based resin composition of the present invention is small, and the dimensional stability is lowered. On the other hand, if it is less than the above lower limit, the flowability is deteriorated and the moldability is deteriorated.

[(B) polycarbonate resin]
The polyester-based resin composition of the present invention contains (B) a polycarbonate resin in addition to (A) a polybutylene terephthalate-based resin.
Polycarbonate resins are optionally branched thermoplastic polymers or copolymers obtained by reacting a dihydroxy compound or a small amount of a polyhydroxy compound with phosgene or a carbonic acid diester. The method for producing the polycarbonate resin is not particularly limited, and one produced by a conventionally known phosgene method (interfacial polymerization method) or melting method (transesterification method) can be used.

The dihydroxy compound as a raw material is preferably an aromatic dihydroxy compound such as 2,2-bis(4-hydroxyphenyl)propane (=bisphenol A), tetramethylbisphenol A, bis(4-hydroxyphenyl)-p-diisopropylbenzene, Hydroquinone, resorcinol, 4,4-dihydroxydiphenyl and the like, preferably bisphenol A. A compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used.

Among the polycarbonate resins mentioned above, aromatic polycarbonate resins derived from 2,2-bis(4-hydroxyphenyl)propane, or 2,2-bis(4-hydroxyphenyl)propane and other aromatic dihydroxy Aromatic polycarbonate copolymers derived from a compound are preferred. It may also be a copolymer mainly composed of an aromatic polycarbonate resin, such as a copolymer with a polymer or oligomer having a siloxane structure. Furthermore, two or more of the above polycarbonate resins may be mixed and used.
Monohydric aromatic hydroxy compounds may be used to control the molecular weight of polycarbonate resins, such as m- and p-methylphenol, m- and p-propylphenol, p-tert-butylphenol, p-long chain Alkyl-substituted phenols and the like can be mentioned.

The viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 20,000 or more, more preferably 23,000 or more, still more preferably 25,000 or more, and particularly preferably 29,000 or more. If the viscosity-average molecular weight is lower than 20,000, the resulting resin composition tends to have low mechanical strength such as impact resistance. Moreover, it is preferably 60,000 or less, more preferably 40,000 or less, and even more preferably 35,000 or less. If it is higher than 60,000, the fluidity of the resin composition may deteriorate, resulting in poor moldability.
In the present invention, the viscosity average molecular weight (Mv) of the polycarbonate resin is obtained by measuring the viscosity of a methylene chloride solution of the polycarbonate resin at 25 ° C. using an Ubbelohde viscometer to determine the intrinsic viscosity ([η]). A value calculated from the following Schnell viscosity formula is shown.
[η]=1.23×10 ⁻⁴ Mv ^0.83

The method for producing the polycarbonate resin is not particularly limited, and polycarbonate resins produced by either the phosgene method (interfacial polymerization method) or the melt method (transesterification method) can be used. Also preferred is a polycarbonate resin prepared by subjecting a polycarbonate resin produced by a melting method to a post-treatment for adjusting the amount of terminal OH groups.
The content of the (B) polycarbonate resin is based on a total of 100 parts by mass of the (A) polybutylene terephthalate resin and (B) the polycarbonate resin, and the (B) polycarbonate resin is 10 to 40 parts by mass, preferably 15 parts by mass. parts or more, more preferably 20 parts by mass or more, preferably 36 parts by mass or less, more preferably 33 parts by mass or less. Below the above lower limit, the effect of improving the impact resistance and toughness of the polyester-based resin composition of the present invention is small, and the dimensional stability is lowered. On the other hand, when the above upper limit is exceeded, the fluidity deteriorates and the moldability deteriorates.

[(C) Copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester]
The polyester-based resin composition of the present invention further comprises (C) a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester, and (D) an α-olefin and a (meth)acrylic acid ester. It also contains a copolymer.

(C) The copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester is not only a terpolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester, but also α - It may be a quaternary or higher multi-component copolymer comprising an olefin, an unsaturated glycidyl compound, a (meth)acrylic acid ester and other monomers.

Examples of the α-olefin in the copolymer (C) include α-olefins having about 2 to 8 carbon atoms such as ethylene, propylene, 1-butene and 1-pentene, with ethylene being particularly preferred.

The unsaturated glycidyl compound is preferably glycidyl (meth)acrylate or unsaturated glycidyl ether such as vinyl glycidyl ether, allyl glycidyl ether, 2-methylallyl glycidyl ether, and particularly glycidyl (meth)acrylate. , that is, glycidyl acrylate or glycidyl methacrylate.

(Meth)acrylate esters include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and methacrylic acid. Examples include propyl acid, butyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate, with butyl acrylate being particularly preferred.

Examples of other monomers that can be components of the quaternary or higher multi-component copolymer include vinyl esters such as vinyl acetate and vinyl propionate, acrylonitrile, styrene, carbon monoxide, maleic anhydride, and the like. can do.

(C) In the copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester, the preferable content of each structural unit is α- Olefin is 50 to 94.5% by mass, more preferably 52 to 85% by mass, more preferably 55 to 75% by mass, and unsaturated glycidyl compound is 0.5 to 20% by mass, more preferably 1 to 18% by mass. %, more preferably 2 to 15% by mass, particularly preferably 3 to 10% by mass, and the (meth)acrylic acid ester is 5 to 49.5% by mass, more preferably 7 to 45% by mass, further preferably is 10 to 40% by mass, particularly preferably 15 to 35% by mass. When other monomers are further used in combination, the other monomers are 0 to 49.5% by mass, more preferably 0.5 to 40% by mass, more preferably 1 to 35% by mass. Copolymerized ones are preferred.

If the content of the unsaturated glycidyl compound is too low, the impact resistance of the polyester resin composition may be impaired, while if the content is too high, the viscosity of the resin rises sharply, making molding difficult. In addition, problems such as the generation of gel in the composition may occur. Further, by using a copolymer obtained by copolymerizing (meth)acrylic acid ester in the above range, it becomes easy to impart good impact resistance to the polyester-based resin composition.

(C) The copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester may be a random copolymer or a graft copolymer, but a random copolymer is used. is preferred. Such random copolymers can be obtained, for example, by radical copolymerization at high temperature and high pressure.
(C) A copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester has a melt flow rate (in accordance with JIS K7210-1999, measured at 190°C under a load of 2.16 kg) of 0.01. It is preferable to use one having a density of up to 1,000 g/10 min, more preferably 0.1 to 200 g/10 min, particularly 1 to 70 g/10 min.

(C) Impact resistance can be improved by blending a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester. The blending amount is 1 to 20 parts by mass, preferably 1.5 parts by mass or more, more preferably 2 parts by mass, with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin, and further It is preferably 3 parts by mass or more, more preferably 16 parts by mass or less, more preferably 12 parts by mass or less, and even more preferably 10 parts by mass or less. If the content is too high, it may cause a decrease in heat resistance, a decrease in mechanical strength, and a deterioration in fluidity.

[(D) Copolymer of α-olefin and (meth)acrylic acid ester]
The polyester-based resin composition of the present invention further contains (D) a copolymer of α-olefin and (meth)acrylic acid ester. Here, (D) the copolymer of α-olefin and (meth)acrylic acid ester is a copolymer different from (C) the above-mentioned copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester. (C) Copolymers of α-olefins, unsaturated glycidyl compounds and (meth)acrylic acid esters are excluded.

The (D) α-olefin of the copolymer of α-olefin and (meth)acrylic acid ester used in the present invention includes α- Olefins can be exemplified, and ethylene is particularly preferred.

(Meth)acrylate esters include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and methacrylic acid. Examples include propyl acid, butyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate.
Among acrylic acid esters and methacrylic acid esters, acrylic acid esters are preferred, and butyl acrylate is particularly preferred.

The ratio of the α-olefin and the (meth)acrylic ester may be adjusted as appropriate. It is preferably at least 10% by mass, more preferably at least 15% by mass, even more preferably at least 20% by mass. The upper limit is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

Each of the α-olefin and (meth)acrylic acid ester may be used alone or in combination of two or more. Further, it may be a copolymer containing monomers other than α-olefin and (meth)acrylic acid ester. In the case of a copolymer containing a monomer other than an olefin and an alkyl (meth)acrylate, the content of the other monomer is preferably 10% by mass or less, and 5% by mass or less, of the monomers constituting the copolymer. is more preferable, and may be 1% by mass or less.

(D) The copolymer of α-olefin and (meth)acrylic acid ester preferably does not contain an epoxy group. (D) Since the copolymer of α-olefin and (meth)acrylic acid ester does not contain epoxy groups, it is difficult to bond with (A) polybutylene terephthalate resin, and the effect as an elastomer is more effectively exhibited. .

(D) The copolymer of α-olefin and (meth)acrylic acid ester is preferably an ethylene-alkyl (meth)acrylate copolymer, more preferably an ethylene-butyl (meth)acrylate copolymer. An ethylene-butyl (meth)acrylate copolymer is more preferred.
More specifically, it is more preferably a copolymer having a structural unit represented by the following formula a and a structural unit represented by the following formula b.

In the above formula, R is an alkyl group having 1 to 6 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, or a butyl group, more preferably a methyl group or a butyl group, and a butyl group. is more preferable.

The ratio between the structural unit a and the structural unit b may be adjusted as appropriate, but the mass ratio of the monomers constituting the structural unit b in the copolymer is preferably 5% by mass or more, and 10% by mass or more. is more preferably 15% by mass or more, and even more preferably 20% by mass or more. The upper limit is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less.

(D) The α-olefin/(meth)acrylic acid ester copolymer preferably has an MFR of 35 to 350 g/10 minutes measured at 190° C. under a load of 2.16 kg. When the MFR is equal to or higher than the above lower limit, high impact resistance can be obtained when the polyester-based resin composition containing this is formed into a molded product. The upper limit of MFR is more preferably 300 g/10 minutes or less, still more preferably 200 g/10 minutes or less, and particularly preferably 150 g/10 minutes or less.

The glass transition point (Tg) of the (D) α-olefin/(meth)acrylic acid ester copolymer used in the present invention is preferably 0° C. or lower, more preferably −30° C. or lower. There is no particular lower limit, but -100° C. or higher is practical. A glass transition point (Tg) is a temperature defined as a temperature obtained by a DSC method according to JIS K7121.
The melting point of the (D) α-olefin/(meth)acrylic acid ester copolymer used in the present invention is preferably 70 to 120°C.

As the copolymer of (D) α-olefin and (meth)acrylic acid ester that can be employed in the resin composition of the present invention, specifically, trade name "LOTRYL (registered trademark) 28BA175" manufactured by Arkema Co., Ltd. ”, “LOTRYL (registered trademark) 35BA40T”, “LOTRYL (registered trademark) 35BA40”, “LOTRYL (registered trademark) 35BA320T”, “LOTRYL (registered trademark) HMA-LV”, “LOTRYL (registered trademark) 35BA320”, etc. mentioned.

By containing (D) a copolymer of α-olefin and (meth)acrylic acid ester, good fluidity and impact resistance can be improved. The content is 1 to 20 parts by mass, preferably 2 parts by mass or more, more preferably 3 parts by mass or more, and 4 parts by mass with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. The amount is more preferably 5 parts by mass or more, particularly preferably 5 parts by mass or more, preferably 18 parts by mass or less, further preferably 16 parts by mass or less, and particularly preferably 15 parts by mass or less. If the blending amount is too large, it may cause a decrease in heat resistance and a decrease in mechanical strength.

The polyester-based resin composition of the present invention comprises (C) a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester, and (D) a copolymer of an α-olefin and a (meth)acrylic acid ester. By containing the coalescence together, the above effects are exhibited, but (C) a copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester, (D) α-olefin and (meth) The total content of the acrylic acid ester copolymer is preferably 3 to 30 parts by mass, more preferably 100 parts by mass in total of (A) the polybutylene terephthalate resin and (B) the polycarbonate resin. 5 to 28 parts by mass, more preferably 7 to 26 parts by mass.

(C) a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester, and (D) a copolymer of an α-olefin and a (meth)acrylic acid ester. ) The content of the copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester is preferably 5 to 42% by mass with respect to the total 100% by mass of (C) and (D). , more preferably 40% by mass or less, 35% by mass or less, 28% by mass or less, and 7% by mass or more, 10% by mass or more, 15% by mass or more, for good impact resistance and fluidity It is particularly preferable because it can be obtained in a balanced manner.

[Glass fiber]
The polyester-based resin composition of the present invention preferably contains glass fibers.

Although the average fiber length of the glass fiber is not particularly limited, it is preferably selected in the range of, for example, 0.1 to 20 mm, more preferably 0.3 to 5 mm. If the average fiber length is less than 0.1 mm, the reinforcing effect may not be sufficiently exhibited, and if it exceeds 20 mm, molding of the obtained polyester-based resin composition may become difficult.

Although the average fiber diameter of the glass fiber is not particularly limited, it is preferably selected in the range of, for example, 1 to 100 μm, more preferably 2 to 50 μm, still more preferably 3 to 30 μm, particularly preferably 5 to 20 μm. Glass fibers with an average fiber diameter of less than 1 μm are not easy to manufacture and may be costly, while glass fibers with an average fiber diameter of more than 100 μm may have reduced tensile strength.

As the glass fiber, it is preferable to use a flat cross-section glass fiber with an average value of the ratio of the major axis to the minor axis (major axis/minor axis) of 1.5 to 8 in terms of bending strength and impact strength, as well as the appearance of the product. , warpage, etc., and is more preferable in terms of good dimensional stability. The average value of the ratio of the major axis to the minor axis (major axis/minor axis) of the fiber cross section of the flat cross section glass fiber is more preferably 1.6 to 7, more preferably 1.7 to 6, and particularly preferably 1.8 to 5.

Moreover, it is preferable to use the glass fiber surface-treated with a surface treatment agent such as a coupling agent. A glass fiber to which a surface treatment agent is attached tends to be excellent in durability, resistance to moist heat, resistance to hydrolysis, and resistance to heat shock, and thus is preferable.

As the surface treatment agent, any conventionally known one can be used, and specifically, silane coupling agents such as aminosilane, epoxysilane, allylsilane, and vinylsilane are preferred.

Among these, aminosilane-based surface treatment agents are preferred, and specifically, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane and γ-(2-aminoethyl)aminopropyltrimethoxysilane are preferred. Examples include:

In addition, as the surface treatment agent, epoxy resins such as novolak type epoxy resins, bisphenol A type epoxy resins, and the like are preferably used. Among them, a novolak type epoxy resin is more preferable.

The silane-based surface treatment agent and the epoxy resin may be used alone or in combination, and it is also preferable to use both together.

In the present invention, the content when glass fiber is contained is preferably 10 to 150 parts by mass with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin, and more. It is preferably 20 to 120 parts by mass, more preferably 30 to 100 parts by mass. Such a content is preferable because impact resistance, heat resistance and fluidity can be improved in a well-balanced manner.

[Inorganic filler]
It is also preferable that the polyester-based resin composition of the present invention contain an inorganic filler other than glass fiber. Any commonly used inorganic filler can be used. If an inorganic filler other than glass fiber is contained, the content is preferably 0.5 to 50 parts by mass with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. , more preferably 1 part by mass or more, more preferably 40 parts by mass or less, and still more preferably 30 parts by mass or less. When the content of the inorganic filler other than the glass fiber (B) exceeds 50 parts by mass, the fluidity is lowered, which is not preferable.

Specific examples of inorganic fillers other than glass fibers (B) include fibrous fillers such as carbon fibers, wollastonite, and potassium titanate fibers; calcium carbonate, titanium oxide, feldspar minerals, clay, Granular or amorphous fillers such as organized clay and glass beads; plate-like fillers such as talc; and scale-like fillers such as glass flakes, mica and graphite can also be used. Among them, talc is preferably used from the viewpoint of mechanical strength, rigidity and heat resistance.

[Flame retardants]
The polyester-based resin composition of the present invention preferably contains a flame retardant.
As flame retardants, known flame retardants for plastics can be used. Specifically, halogen flame retardants, phosphorus flame retardants (melamine polyphosphate, etc.), nitrogen flame retardants (melamine cyanurate, etc.), Hydroxide (such as magnesium hydroxide).
A brominated flame retardant is more preferable as the halogen-based flame retardant.

As the brominated flame retardant, any conventionally known brominated flame retardant used for thermoplastic resins can be used. Such brominated flame retardants include aromatic compounds, and specific examples include polybrominated benzyl (meth)acrylates such as pentabromobenzyl polyacrylate, polybromophenylene ethers, brominated polystyrene, brominated epoxy compounds such as epoxy oligomers of tetrabromobisphenol A; brominated imide compounds such as N,N'-ethylenebis(tetrabromophthalimide) (EBTPI); and brominated polycarbonates.

Among them, polybrominated benzyl (meth)acrylates such as pentabromobenzyl polyacrylate, brominated epoxy compounds such as epoxy oligomers of tetrabromobisphenol A, brominated polystyrene, and brominated polycarbonates are preferred, particularly from the viewpoint of good thermal stability. A brominated epoxy compound is preferred from the viewpoint of cost and flame retardancy.

As the brominated polycarbonate-based flame retardant, for example, a brominated polycarbonate obtained from brominated bisphenol A, particularly tetrabromobisphenol A is preferable. Its terminal structure includes a phenyl group, a 4-t-butylphenyl group, a 2,4,6-tribromophenyl group, and the like, particularly those having a 2,4,6-tribromophenyl group in the terminal group structure. is preferred.

The average number of carbonate repeating units in the brominated polycarbonate flame retardant may be appropriately selected and determined, but is usually 2-30. If the average number of repeating carbonate units is small, the polybutylene terephthalate-based resin (A) may decrease in molecular weight during melting. Conversely, if it is too large, the melt viscosity of the polycarbonate resin (B) increases, causing poor dispersion in the molded product, and the external appearance of the molded product, particularly the glossiness, may deteriorate. Therefore, the average number of repeating units is preferably 3 to 15, particularly preferably 3 to 10.

The molecular weight of the brominated polycarbonate-based flame retardant is arbitrary, and may be appropriately selected and determined. The viscosity-average molecular weight of the brominated polycarbonate-based flame retardant can be obtained by the same method as for measuring the viscosity-average molecular weight of the polycarbonate resin (B).

The brominated polycarbonate flame retardant obtained from the brominated bisphenol A can be obtained, for example, by a conventional method of reacting the brominated bisphenol with phosgene. End capping agents include aromatic monohydroxy compounds, which may be substituted with halogens or organic groups.

Polybrominated benzyl (meth)acrylates are polymers obtained by polymerizing benzyl (meth)acrylates containing bromine atoms alone, or by copolymerizing two or more of them, or by copolymerizing them with other vinyl monomers. The bromine atom is attached to a benzene ring, and the number of additions is preferably 1 to 5, more preferably 4 to 5 per benzene ring.

Examples of the bromine atom-containing benzyl acrylate include pentabromobenzyl acrylate, tetrabromobenzyl acrylate, tribromobenzyl acrylate, and mixtures thereof. Benzyl methacrylate containing a bromine atom includes methacrylates corresponding to the above-described acrylates.

Other vinyl monomers used for copolymerization with benzyl (meth)acrylate containing a bromine atom include, for example, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, and benzyl acrylate. Acrylic acid esters; Methacrylic acid esters such as methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate and benzyl methacrylate; Unsaturated carboxylic acids such as styrene, acrylonitrile, fumaric acid and maleic acid or their anhydrides; Vinyl acetate , vinyl chloride, and the like.

These are usually used in an equimolar amount or less, preferably in an amount of 0.5 or less times the molar amount of benzyl (meth)acrylate containing a bromine atom.

As the vinyl-based monomer, xylene diacrylate, xylene dimethacrylate, tetrabrom xylene diacrylate, tetrabrom xylene dimethacrylate, butadiene, isoprene, divinylbenzene, etc. can also be used, and these usually contain a bromine atom. 0.5-fold molar amount or less can be used with respect to the benzyl acrylate or benzyl methacrylate used.

As the polybrominated benzyl (meth)acrylate, pentabromobenzyl polyacrylate is preferable from the viewpoint of its high bromine content and high electrical insulation properties (anti-tracking properties).

Specific examples of brominated epoxy compounds include bisphenol A-type brominated epoxy compounds represented by tetrabromobisphenol A epoxy compounds.

The molecular weight of the brominated epoxy compound is arbitrary and may be determined by appropriately selecting it. Preferably, the weight average molecular weight (Mw) is 3000 to 100000, and among them, the higher the molecular weight, the more specifically Mw. is preferably 15,000 to 80,000, especially 18,000 to 78,000, more preferably 20,000 to 75,000, particularly 22,000 to 70,000. Even within this range, those having a high molecular weight are preferred.
The epoxy equivalent of the brominated epoxy compound is preferably 3,000 to 40,000 g/eq, more preferably 4,000 to 35,000 g/eq, and particularly preferably 10,000 to 30,000 g/eq.

A brominated epoxy oligomer can also be used in combination as a brominated epoxy compound flame retardant. At this time, for example, by using about 0 to 50% by mass of an oligomer having an Mw of 5000 or less, flame retardancy, releasability and fluidity can be appropriately adjusted. The bromine atom content in the brominated epoxy compound is arbitrary, but is usually 10% by mass or more, preferably 20% by mass or more, particularly preferably 30% by mass or more, in order to impart sufficient flame retardancy. The upper limit is 60% by mass, preferably 55% by mass or less.

The content of the flame retardant is preferably 3 to 30 parts by mass, more preferably 7 parts by mass or more, with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. It is preferably 10 parts by mass or more, more preferably 25 parts by mass or less, still more preferably 23 parts by mass or less, and particularly preferably 20 parts by mass or less. If the content of the flame retardant is too small, the flame retardancy of the resin composition used in the present invention will be insufficient. .

[Antimony compound]
The polybutylene terephthalate resin composition of the present invention preferably contains an antimony compound as a flame retardant aid.
Preferred examples of antimony compounds include antimony trioxide (Sb ₂ O ₃ ), antimony pentoxide (Sb ₂ O ₅ ) and sodium antimonate. Among these, antimony trioxide is preferable from the viewpoint of impact resistance.

The antimony compound is preferably blended as a masterbatch with (A) polybutylene terephthalate resin. This makes it easier for the antimony compound to exist in the (A) polybutylene terephthalate resin phase, suppresses adverse effects on the (B) polycarbonate resin, and tends to suppress a decrease in impact resistance.

The content of the antimony compound in the masterbatch is preferably 20 to 90% by mass. If the antimony compound is less than 20% by mass, the proportion of the antimony compound in the flame retardant masterbatch is small, and the effect of improving the flame retardancy of the polybutylene terephthalate resin containing this compound is small. On the other hand, if the content of the antimony compound exceeds 90% by mass, the dispersibility of the antimony compound tends to decrease. It is not preferable because the workability at the time of production is remarkably deteriorated, for example, problems such as unstable strands and easy breakage during production using an extruder tend to occur.
The lower limit of the content of the antimony compound in the masterbatch is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably 50% by mass or more, and the upper limit is preferably 88% by mass. Yes, more preferably 85% by mass or less.

The content of the antimony compound is preferably 1 to 15 parts by mass, more preferably 2 parts by mass or more, and even more preferably It is 2.5 parts by mass or more, more preferably 10 parts by mass or less, still more preferably 7 parts by mass or less, especially 6 parts by mass or less, and particularly preferably 5 parts by mass or less. If it is less than the above lower limit, the flame retardancy tends to be lowered, and if it exceeds the above upper limit, the crystallization temperature is lowered, the releasability is deteriorated, and mechanical properties such as impact resistance are lowered.

[Release agent]
The polyester-based resin composition of the present invention preferably contains a release agent. As the release agent, known release agents that are commonly used for polyester resins can be used. Among them, polyolefin compounds, fatty acid ester compounds, and silicone compounds are selected because of their high release effect. One or more release agents are preferred, and fatty acid ester compounds are particularly preferred.

Examples of polyolefin compounds include compounds selected from paraffin waxes and polyethylene waxes. Among them, those having a weight average molecular weight of 700 to 10,000, more preferably 900 to 8,000 are preferred.

Examples of fatty acid ester compounds include saturated or unsaturated aliphatic monovalent or divalent carboxylic acid esters, fatty acid esters such as glycerin fatty acid esters, sorbitan fatty acid esters, and partially saponified products thereof. Among them, mono- or di-fatty acid esters composed of fatty acids having 11 to 28 carbon atoms, preferably 17 to 21 carbon atoms, and alcohols are preferred.

Aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, melissic acid, tetralyacontanoic acid, montanic acid, adipic acid, and azelaic acid. etc. Also, the aliphatic carboxylic acid may be an alicyclic carboxylic acid.

Alcohols may include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have substituents such as fluorine atoms and aryl groups. Among these, monohydric or polyhydric saturated alcohols having 30 or less carbon atoms are preferred, and saturated monohydric or polyhydric alcohols having 30 or less carbon atoms are more preferred. Here, the term "aliphatic" also includes alicyclic compounds.

Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. is mentioned.

The above ester compound may contain aliphatic carboxylic acid and/or alcohol as impurities, or may be a mixture of a plurality of compounds.

Specific examples of fatty acid ester compounds include glycerin monostearate, glycerin monobehenate, glycerin dibehenate, glycerin-12-hydroxy monostearate, sorbitan monobehenate, pentaerythritol monostearate, and pentaerythritol distearate. rate, stearyl stearate, ethylene glycol montanic acid ester, and the like.

As the silicone-based compound, a modified compound is preferable from the viewpoint of compatibility with the polybutylene terephthalate-based resin. Modified silicone oils include silicone oils in which organic groups are introduced into side chains of polysiloxane, silicone oils in which organic groups are introduced into both ends and/or one end of polysiloxane, and the like. Examples of the organic group to be introduced include an epoxy group, an amino group, a carboxyl group, a carbinol group, a methacrylic group, a mercapto group, a phenol group and the like, preferably an epoxy group. As the modified silicone oil, a silicone oil obtained by introducing an epoxy group into the side chain of polysiloxane is particularly preferable.

The content of the release agent is preferably 0.1 to 3 parts by mass, preferably 0.2 to 2.5 parts by mass, with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. Parts by mass are more preferred. If the amount is less than 0.1 parts by mass, the surface properties tend to deteriorate due to poor mold release during melt molding. A haze may be seen on the body surface. The content of the release agent is more preferably 0.5 to 2 parts by mass.

[Stabilizer]
The polyester resin composition of the present invention contains a stabilizer to improve thermal stability, prevent transesterification, suppress rapid viscosity change during molding retention, suppress voids due to foaming, and mechanical strength. , is preferable in that it has the effect of preventing deterioration of transparency, hue and surface appearance. As stabilizers, phosphorus stabilizers, sulfur stabilizers and phenol stabilizers are preferred, and phosphorus stabilizers and phenol stabilizers are more preferred.

Phosphorous stabilizers include phosphorous acid, phosphoric acid, phosphites, phosphate esters, etc. Among them, organic phosphoric acid ester compounds are preferred.

The organic phosphoric acid ester compound has a partial structure in which 1 to 3 alkoxy groups or aryloxy groups are bonded to a phosphorus atom. A substituent may be further bonded to these alkoxy groups and aryloxy groups. Preferably, an organic phosphoric acid ester compound represented by any one of the following general formulas (1) to (5) is used. You may use an organic phosphoric acid ester compound in combination of 2 or more types.

一般式（１）中、Ｒ^１～Ｒ^４は、それぞれ独立して、アルキル基又はアリール基を表す。Ｍはアルカリ土類金属又は亜鉛を表す。

In general formula (1), R ¹ to R ⁴ each independently represent an alkyl group or an aryl group. M represents an alkaline earth metal or zinc.

一般式（２）中、Ｒ^５はアルキル基又はアリール基を表し、Ｍはアルカリ土類金属又は亜鉛を表す。

In general formula ( ² ), R5 represents an alkyl group or an aryl group, and M represents an alkaline earth metal or zinc.

一般式（３）中、Ｒ^６～Ｒ^１１は、それぞれ独立して、アルキル基又はアリール基を表す。Ｍ’は３価の金属イオンとなる金属原子を表す。

In general formula (3), R ⁶ to R ¹¹ each independently represent an alkyl group or an aryl group. M' represents a metal atom that becomes a trivalent metal ion.

一般式（４）中、Ｒ^１２～Ｒ^１４は、それぞれ独立して、アルキル基又はアリール基を表す。Ｍ’は３価の金属イオンとなる金属原子を表し、２つのＭ’はそれぞれ同一であっても異なっていてもよい。

In general formula (4), R ¹² to R ¹⁴ each independently represent an alkyl group or an aryl group. M' represents a metal atom that becomes a trivalent metal ion, and two M's may be the same or different.

一般式（５）中、Ｒ^１５はアルキル基又はアリール基を表す。ｎは０～２の整数を表す。なお、ｎが０のとき、３つのＲ^１５は同一でも異なっていてもよく、ｎが１のとき、２つのＲ^１５は同一でも異なっていてもよい。

In general formula (5), R ¹⁵ represents an alkyl group or an aryl group. n represents an integer of 0 to 2; When n is 0, three R ¹⁵ may be the same or different, and when n is 1, two R ¹⁵ may be the same or different.

In general formulas (1) to (5), R ¹ to R ¹⁵ are generally alkyl groups having 1 to 30 carbon atoms or aryl groups having 6 to 30 carbon atoms. From the viewpoint of retention heat stability, chemical resistance, moist heat resistance, etc., it is preferably an alkyl group having 2 to 25 carbon atoms, and most preferably an alkyl group having 6 to 23 carbon atoms. The alkyl group includes octyl group, 2-ethylhexyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group, hexadecyl group, octadecyl group and the like. Further, M in general formulas (1) and (2) is preferably zinc, and M' in general formulas (3) and (4) is preferably aluminum.

Preferred specific examples of organic phosphoric ester compounds include bis(distearyl acid phosphate) zinc salt as the compound of general formula (1), monostearyl acid phosphate zinc salt as the compound of general formula (2), and general formula (3). ) as the compound of tris(distearyl acid phosphate) aluminum salt, and as the compound of the general formula (4), a salt of one monostearyl acid phosphate and two monostearyl acid phosphate aluminum salts, the general formula Compounds of (5) include monostearyl acid phosphate and distearyl acid phosphate. These may be used singly or as a mixture.

As an organic phosphate ester compound, it has a very high effect of suppressing transesterification, has good thermal stability during molding, and has excellent moldability. Bis(distearyl acid phosphate) zinc, which is a zinc salt of an organic phosphoric acid ester compound represented by the general formula (1), from the viewpoint of stable molding and excellent hydrolysis resistance and impact resistance. It is preferable to use a salt, a zinc salt of stearyl acid phosphate such as monostearyl acid phosphate zinc salt, which is a zinc salt of the organic phosphoric acid ester compound represented by the general formula (2). Commercially available products include "JP-518Zn" manufactured by Johoku Kagaku Kogyo Co., Ltd. and the like.

As the sulfur-based stabilizer, any conventionally known sulfur atom-containing compound can be used, and thioethers are particularly preferable. Specific examples include didodecylthiodipropionate, ditetradecylthiodipropionate, dioctadecylthiodipropionate, pentaerythritol tetrakis(3-dodecylthiopropionate), thiobis(N-phenyl-β-naphthylamine ), 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyldithiocarbamate, nickel isopropylxanthate, trilauryltrithiophosphite. Among these, pentaerythritol tetrakis(3-dodecylthiopropionate) is preferred.

Phenolic stabilizers include, for example, pentaerythritol tetrakis (3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), octadecyl-3-(3,5-di-tert-butyl-4 -hydroxyphenyl)propionate, thiodiethylenebis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), pentaerythritol tetrakis(3-(3,5-di-neopentyl-4-hydroxyphenyl) ) propionate) and the like. Among these, pentaerythritol-letetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl ) propionate is preferred.

One type of stabilizer may be contained, or two or more types may be contained in any combination and ratio, and it is particularly preferable to use two types of a phosphorus stabilizer and a phenolic stabilizer in combination. .

The content of the stabilizer is preferably 0.001 to 2 parts by mass with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. If the content of the stabilizer is less than 0.001 part by mass, it is difficult to expect an improvement in the thermal stability and compatibility of the resin composition, and a decrease in molecular weight and deterioration in color during molding are likely to occur. If it exceeds, the amount becomes excessive, and the generation of silver and the deterioration of the hue tend to occur more easily. The stabilizer content is more preferably 0.01 to 1.5 parts by mass, and still more preferably 0.1 to 1 part by mass.

[Carbon black]
The polyester-based resin composition of the present invention preferably contains carbon black.
Carbon black is not limited in its type, raw material type, and production method, and any of furnace black, channel black, acetylene black, ketjen black, etc. can be used. Although the number average particle diameter is not particularly limited, it is preferably about 5 to 60 nm.

The content of carbon black is preferably 0.1 to 4.0 parts by mass, more preferably 0.2 to 3.0 parts by mass, with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. It is 0 parts by mass. If it is less than 0.1 part by mass, the desired color may not be obtained or the effect of improving weather resistance may not be sufficient, and if it exceeds 4.0 parts by mass, mechanical properties may deteriorate.

Carbon black is preferably blended in advance as a masterbatch containing carbon black at a high concentration in order to improve handleability during production of the resin composition and uniform dispersibility in the resin composition. In this case, the resin used in the carbon black masterbatch may be (A) a polybutylene terephthalate resin, other resins such as polycarbonate resin, polyethylene terephthalate resin, styrene resin (for example, AS resin), Polyethylene resin or the like may be used. It is preferable to use (A) a polybutylene terephthalate-based resin because it is easy to disperse high-concentration carbon black and to easily form a masterbatch.
The carbon black concentration of the carbon black masterbatch is usually about 10 to 60% by mass.

[Other ingredients]
The polyester-based resin composition of the present invention may optionally contain various resin additives other than those mentioned above within a range that does not impair the effects of the present invention. Various resin additives include anti-dripping agents, ultraviolet absorbers, weather stabilizers, coloring agents such as dyes and pigments other than carbon black, lubricants, catalyst deactivators, antistatic agents, foaming agents, plasticizers, crystals A nucleating agent, a crystallization accelerator, and the like are included.

The polyester-based resin composition of the present invention may optionally contain other thermoplastic resins, thermosetting resins, and the like within a range that does not impair the effects of the present invention. Other thermoplastic resins include polyethylene resins, polypropylene resins, acrylic resins, polyacetal resins, polyphenylene oxide resins, polyphenylene sulfide resins, liquid crystal polyester resins, etc. Thermosetting resins include phenol resins, melamine resins, Examples include silicone resins and epoxy resins. These may be one type or two or more types.

However, when containing other resins other than the resins of the essential components described above, the content is 40 parts by mass or less with respect to a total of 100 parts by mass of (A) polybutylene terephthalate resin and (B) polycarbonate resin. more preferably 30 parts by mass or less, more preferably 20 parts by mass or less, especially 10 parts by mass or less, particularly 5 parts by mass or less, and most preferably 2 parts by mass or less.

The method for producing the polyester-based resin composition of the present invention is not limited to a specific method, but the melting and kneading method is preferred. The melting/kneading method can be a method commonly used for thermoplastic resins.

Melting and kneading methods include, for example, (A) polybutylene terephthalate-based resin, (B) polycarbonate resin, (C) copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester, and (D). A copolymer of α-olefin and (meth)acrylic acid ester, and if necessary, the above-mentioned desired components are uniformly mixed with a Henschel mixer, ribbon blender, V-type blender, tumbler, etc., and then uniaxially or multiaxially kneaded. A method of melting and kneading with an extruder, a roll, a Banbury mixer, Laboplastomill (Brabender) or the like can be mentioned. If necessary, the glass fiber or the like is preferably supplied from the side feeder of the kneading extruder so that breakage of the reinforcing filler can be suppressed and dispersed.

The temperature and kneading time for melting and kneading can be selected according to the type of components constituting the resin component, the ratio of the components, the type of melting and kneading machine, etc. The temperature for melting and kneading is 200 to 300. °C range is preferred. When it exceeds 300 ° C., (A) polybutylene terephthalate resin, (B) polycarbonate resin and (C) copolymer of α-olefin, unsaturated glycidyl compound and (meth) acrylic acid ester, (D) α-olefin and (meth)acrylic acid ester copolymers and the like become a problem due to heat deterioration, and the physical properties of the molded article may deteriorate and the appearance may deteriorate.

In terms of fluidity (moldability), the polyester resin composition of the present invention thus obtained has a melt volume rate (MVR) of 8 cm ³ /10 min or more measured under conditions of a temperature of 265° C. and a load of 5 kgf. , more preferably 9 cm ³ /10 min or more, and even more preferably 10 cm ³ /10 min or more.
Here, MVR is the melt flow volume MVR per unit time (unit: cm ³ /10 min) measured under conditions of 265° C. and a load of 5 kgf using a melt indexer. Examples of the melt indexer include those manufactured by Takara Industry Co., Ltd., and the like.

In terms of heat resistance, the ball pressure temperature is preferably 180° C. or higher, more preferably 190° C. or higher.
Here, the ball pressure temperature can be measured, for example, using a test piece of 100×100×3 mmt according to the Electrical Appliances and Materials Research Committee Method B (in oil). Specifically, a φ5 mm steel ball was pressed with a load of 20 N for 1 hour in oil at the test temperature, and the temperature of the oil when the dent depth of the test piece reached 0.209 mm was defined as the ball pressure temperature.

The method for producing a molded article from the polyester resin composition of the present invention is not particularly limited, and the molding methods conventionally employed for thermoplastic resins, that is, injection molding, insert molding, and blow molding. , extrusion molding, compression molding, etc., but injection molding is particularly preferred. As for the injection molding method, a conventional method applied to injection molding of polybutylene terephthalate resin may be applied. By using the polyester-based resin composition of the present invention, it is possible to obtain a molded article having excellent fluidity (moldability) and good impact resistance and heat resistance even with a one-point gate.

As the molded article, one integrally molded by injection molding is preferable. As the molded product by injection molding, it is particularly preferable to have a shape having a bottom portion recessed by surrounding rising walls, a volume of 200 to 20000 cm ³ and a minimum thickness of 3 mm or less.

Such preferred molded articles will be described below.
There is no particular limitation on the shape of the bottom portion recessed by the surrounding rising walls. It may be a flat plate or a curved surface, and may have uneven portions, rib portions, hinge portions, and boss portions on a part or the entire surface.

When the bottom portion is a curved surface, the cross-sectional shape of the bottom portion in the height direction of the molded product includes, for example, substantially semicircular, substantially semielliptical, substantially semielliptical, substantially rectangular, substantially square, arc-shaped, and these shapes. , a shape in which a tapered shape and a circular arc shape are combined, a shape in which a tapered shape and a flat plate shape are combined, and the like. Further, the cross-sectional shape of the bottom surface in the plane direction perpendicular to the height direction of the molded product is, for example, substantially circular, substantially semicircular, substantially elliptical, substantially semielliptical, substantially oval, substantially semielliptical, substantially triangular. , substantially rectangular, substantially square, and combinations of these shapes.

The volume of the molded product is preferably 200-18000 cm ³ , more preferably 300-15000 cm ³ , still more preferably 500-12000 cm ³ . Also, the minimum thickness is preferably 0.1 to 3 mm, more preferably 0.5 to 2.5 mm.

Here, the volume of the molded product refers to the volume of the space formed by the rising wall around the molded product and the bottom part recessed by the rising wall,
(Height of surrounding rising wall) x (Maximum projected area of bottom recessed by surrounding rising wall)
can be obtained by In addition, if the bottom part is not flat, such as having a curved surface or unevenness, or if the height of the surrounding rising wall varies depending on the part, the height of the rising wall may vary depending on the part of the molded product. different. Therefore, in such a case, the height of the portion where the height of the rising wall is the highest is used as the height of the rising wall to calculate the volume of the molded product. The height of the rising wall does not include the effects of bosses, ribs, and the like.

Also, the minimum thickness of the molded product is the minimum thickness of the portion excluding ribs, hinges, bosses, etc., if the molded product has them.
Having such a volume, average and minimum thickness means that the molded product is thin and large, and the space formed by the molded product cannot accommodate or hold other articles or products. is also possible. The molded article thus constructed can be easily and stably molded due to the excellent fluidity of the polyester resin composition of the present invention. It has become possible to have excellent impact resistance and heat resistance.

The molded product preferably has at least a portion with a minimum thickness of 3 mm or less. is 35% or more, preferably 40% or more. Here, if the molded product has ribs, hinges, bosses, etc., the area is the sum of the areas excluding these parts, and means the total area of the bottom surface and surrounding rising walls. If there are other parts at positions facing the bottom part, etc., the other parts are also included in the area.

The molded article preferably has an average thickness of 1 to 5 mm, more preferably 1 to 4 mm, even more preferably 1 to 3.5 mm. The average thickness of the molded product is the average value obtained by measuring the thickness of the portions excluding ribs, hinges, bosses, etc., if the molded product has them.

Furthermore, the molded article preferably has an area of the bottom portion recessed by the surrounding rising walls of 100 to 900 cm ² , more preferably 130 to 800 cm ² , and even more preferably 150 to 700 cm ² . . The area of the bottom surface means the maximum projected area of the bottom surface.

The injection molding method, which is a preferred method for producing molded articles, is not particularly limited, and typical examples thereof include a general injection molding method, a gas assist molding method, an injection compression molding method, and the like.

During molding, the temperature of the resin in the injection cylinder is preferably in the range of 230 to 290.degree. C., more preferably 240 to 280.degree.

As the mold for injection molding, even multi-point gates can be applied, but a mold with one or several pin gates in the center is recommended for ease of mold design and avoidance of weld problems. Because of the excellent fluidity of the polyester-based resin composition of the present invention, it is possible to easily and stably mold thin and large-sized molded articles of the present invention even with a one-point gate.

The resin composition filling volume per gate during injection molding is preferably 50 ml or more, more preferably 70 ml or more, even more preferably 100 ml or more, and particularly preferably 200 ml or more. The polyester-based resin composition using such a resin composition filling volume per gate can be easily achieved in the present invention, so that the large molded article of the present invention can be molded even with a single gate. The resin composition filling volume per gate during injection molding is a value calculated by dividing the total resin filling volume of the molded product by the number of gates.

A molded article using the resin composition of the present invention has high impact resistance and heat resistance, and can be easily manufactured even if it has a complicated shape and a large size.
Molded products that require these features include, for example, electric/electronic parts, home appliance parts, automobile parts, OA equipment parts, machine mechanism parts, building material parts, other precision equipment parts, various containers, etc. Applicable. In particular, it is suitable for household appliance parts, especially product parts that require high impact resistance, moldability (fluidity) and heat resistance.

Among them, the product has a heating part (heating part) by an electric heater (including resistance heating, dielectric heating, microwave heating, induction heating, etc.), and it is located within 30 mm, particularly within 20 mm from the heating part It can be suitably used for parts that are arranged in such a way as to In addition, "located within 30 mm from the heating part" refers to a state in which at least a part of the molded product is located within 30 mm from the heating part, and the molded product and the heating part are in direct contact. is also included.
In particular, the molded article obtained by molding the resin composition of the present invention has sufficient heat resistance to be used as a part of an actual product. It can also be used for product parts that require high heat resistance, such as those located within 30 mm from the Furthermore, since the parts made of the polyester-based resin composition of the present invention have excellent heat resistance, problems such as deterioration of mechanical properties and discoloration due to thermal deterioration are unlikely to occur even when placed in the vicinity of the heating unit. There are other advantages as well.

Examples of parts of products having a heating part (heat generating part) include rice cookers, IH cookers, hot plates, water heaters, microwave ovens, oven ranges, cooking heaters, electric pots, coffee makers, electric heaters, far-infrared heaters, and tableware. Examples include parts of dryers, fan heaters, irons, hair dryers, lighting equipment, and the like.

Raw material components used in the following examples and comparative examples are as shown in Table 1 below.

(Examples 1-3, Comparative Examples 1-9)
<Production of polyester resin composition>
Among the components listed in Table 1, each component other than glass fiber is blended at the ratio (described in parts by mass) shown in Table 2 below, and this is blended with a 30 mm vent type twin screw extruder (Japan Using a twin-screw extruder “TEX30α” manufactured by Steelworks Co., Ltd.), glass fibers are supplied from a side feeder, melted and kneaded at a barrel temperature of 270 ° C., extruded into strands, pelletized with a strand cutter, and polyester A pellet of the system resin composition was obtained.

<Measurement evaluation method>
Various physical properties and performances in Examples and Comparative Examples were measured and evaluated by the following methods.
[Impact resistance evaluation: impact hammer test]
After drying the pellets obtained by the above production method at 120 ° C. for 5 hours, using an injection molding machine manufactured by Nissei Plastic Industry Co., Ltd. (clamping force 80 T), under the conditions of a cylinder temperature of 260 ° C. and a mold temperature of 80 ° C. A molded 100×100×2 mmt injection-molded test piece was used as the test piece.
Four kinds of square frames with internal areas of 15 cm ² , 20 cm ² , 25 cm ² and 30 cm ² were prepared as pedestals on which the test pieces were placed, using a resin piece with a width of 10 mm and a thickness of 4 mm. The above 100 × 100 × 2 mmt test piece was placed on each pedestal, and the impact was applied 10 times to the center with an impact hammer pulled with an energy of 0.5 J, and it did not break ( The number of non-breaks (number of clears) was counted and evaluated according to the following criteria.
◎: No break for all 10 times ○: No break for 5 to 9 times △: No break for 1 to 4 times ×: No break for all 10 times Even if the resin frame is small, samples with a high non-break ratio have excellent impact resistance. can be judged.

[Fluidity: injection peak pressure]
The injection peak pressure (unit: MPa) when molding the impact hammer test piece was read and used as an index of fluidity. A value of 110 MPa or less was used as a criterion for excellent fluidity.

[Design value of intrinsic viscosity of polybutylene terephthalate resin]
The intrinsic viscosity IV at 30° C. of the raw material polybutylene phthalate resin (mixture of A1 to A3 shown in Table 2) was measured before charging (referred to as “designed IV value” in the table).
The intrinsic viscosity is a value (unit: dl/g) measured at 30° C. in a 1:1 (mass ratio) mixed solvent of tetrachloroethane and phenol.
The above evaluation results are shown in Table 2 below.

In Table 2 above, Comparative Examples 1 to 3 show that by increasing the intrinsic viscosity of (A) polybutylene terephthalate resin without blending the (C) component and (D) component of the present invention, the impact resistance Although this is an example intended to improve the IV value, it can be seen that although the impact resistance is improved by increasing the IV value, it is not sufficient, and the fluidity deterioration is more remarkable.
Further, Comparative Examples 4 to 7 are examples in which the (A) polybutylene terephthalate resin was blended with the (C) component and the (D) component without blending the (B) polycarbonate resin. Although the impact resistance is slightly improved by increasing the intrinsic viscosity, it is found to be insufficient.
Comparative Examples 8 and 9 are examples in which only either component (C) or component (D) is blended, but in Comparative Example 8 in which only component (D) is blended alone, the impact resistance is slightly improved. is insufficient, and in Comparative Example 9 in which only the component (C) is blended alone, the impact resistance is improved, but the fluidity is poor.
On the other hand, in Examples 1 to 3, which satisfy the requirements of the present application, the impact resistance is extremely good, at an acceptable level, and the fluidity is also good.

The polyester-based resin composition of the present invention is excellent in impact resistance, fluidity (moldability), and heat resistance, so it can be widely used in various applications. It can be applied to automobile parts, OA equipment parts, machine mechanism parts, building material parts, other precision equipment parts, various containers, etc., and its usability is high.

Claims (3)

(A) containing 60 to 90 parts by mass of polybutylene terephthalate resin and (B) 10 to 40 parts by mass of polycarbonate resin for a total of 100 parts by mass of (A) and (B),
(C) 1 to 20 parts by mass of a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester ;
(D) Copolymer of α-olefin and (meth)acrylic acid ester [Excluding (C) Copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester. ] from 1 to 20 parts by mass , and
Contains 3 to 30 parts by mass of a brominated flame retardant ,
(C) the content of the copolymer of α-olefin, unsaturated glycidyl compound and (meth)acrylic acid ester is 5 to 42% by mass with respect to the total 100% by mass of (C) and (D);
(D) When the copolymer of α-olefin and (meth)acrylic acid ester is a copolymer containing other monomers other than olefin and alkyl (meth)acrylate, the other monomer constitutes the copolymer 1% by mass or less of the monomer that
(D) the copolymer of α-olefin and (meth)acrylic acid ester has an MFR of 35 to 350 g/10 min;
A polyester-based resin composition for parts of products having a heating part with an electric heater . The total content of (C) a copolymer of an α-olefin, an unsaturated glycidyl compound and a (meth)acrylic acid ester and (D) a copolymer of an α-olefin and a (meth)acrylic acid ester is (A) The polyester resin composition according to claim 1, which is 3 to 30 parts by mass with respect to a total of 100 parts by mass of (B). 3. The polyester resin composition according to claim 1, wherein the polycarbonate resin (B) has a viscosity average molecular weight of 25,000 to 60,000.