JPS6261066B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester resin composition, and more specifically to a glass fiber-reinforced polyethylene terephthalate resin that can form molded products with excellent moldability, particularly mold release properties, and molding machine screw penetration properties, as well as excellent appearance, particularly gloss and surface whitening prevention. Regarding the composition. Reinforced resin compositions made by blending glass fibers with polyethylene terephthalate resin are well known. In other words, when polyethylene terephthalate resin is not blended with glass fiber, its impact resistance is particularly low, and its use as a so-called plastic molding material is limited, but by reinforcing it with glass fiber, it has significantly improved impact resistance. It has become clear that it can improve impact resistance, heat resistance, etc., and it has come to be widely used in electrical insulation parts, mechanical parts, etc. However, simply blending glass fiber with polyethylene terephthalate resin does not provide the desired properties as a molding material, and various improvements have been made and proposed. For example, in order to increase the crystallization rate in the mold during injection molding, a compound with a crystal nucleation effect is added as a so-called crystal nucleation agent, thereby increasing the density of the molded product and increasing the crystallization rate at high temperatures. Examples of such crystal nucleating agents include inorganic solid substances such as talc, carbon black, graphite, and metal salts of organic monocarboxylic acids, especially sodium and potassium salts. is said to be valid. However, it cannot be said that the crystallization rate is sufficiently high for practical purposes only by blending such a crystal nucleating agent. Therefore, as a method for further promoting crystallization during molding, a method has been proposed in which molten resin is injected into a mold that has been heated to a high temperature in advance and solidified. It is usually desirable for this mold temperature to be 70°C or higher, but in order to improve the appearance of the molded product, especially its surface gloss and dimensional stability at high temperatures, it is required to be 100°C or higher. especially
It is preferable to maintain the temperature at about 140°C. However, on the other hand, when molding is carried out at such high mold temperatures, working conditions become poor, and moldings are often deformed or destroyed when released from the mold due to insufficient cooling and solidification of the molded material. The problem is that there are many cases. For this reason, a so-called mold release agent is usually added for the purpose of improving mold release properties and thereby shortening the molding cycle. Examples of compounds having such a mold release effect include, for example, mainly:
It has been proposed to incorporate acid mixtures of aliphatic monocarboxylic acids having a chain length of 20 to 32 carbon atoms (hereinafter referred to as montan wax acids). However, there are few that satisfy both of these crystal nucleation and mold release properties, and in particular, there are very few that can satisfy injection molding conditions on an industrial scale. Therefore, it is desired to develop a technique that satisfies both the moldability and molded product properties of glass fiber-reinforced polyethylene terephthalate resin compositions. As a result of various studies focusing on this point, the present inventors found that depending on the combination of the crystal nucleating agent and the mold release agent, the mutual compounds may have an adverse effect on each other, resulting in the desired properties being obtained. I learned that there are many things that cannot be done. For example, if the above-mentioned sodium salt or potassium salt of the organic monocarboxylic acid and montan wax acid are used simultaneously in polyethylene terephthalate resin, the degree of polymerization of the polyethylene terephthalate resin in the composition will be significantly reduced, and as a result, the strength of the molded product will be extremely low. It has been found that the so-called whitening phenomenon in which the appearance characteristics, particularly the surface of the molded product, becomes white is likely to occur. This phenomenon is presumed to occur due to the acid decomposition of polyethylene terephthalate resin by montanwax acid, but the organic monocarboxylic acid sodium salt or potassium salt also plays a catalytic effect on this reaction, and this catalytic effect causes It is presumed that the acceleration of the decomposition reaction is also a major influence. In such cases, for example, it may be effective to use a polyethylene terephthalate resin with a high degree of polymerization as a raw material in order to avoid a decrease in reinforcement of the molded product due to a decrease in the degree of polymerization of the polyethylene terephthalate resin, but in reality, Polyethylene terephthalate resin with a high degree of polymerization has a high melt viscosity, and the decrease in the degree of polymerization due to montan wax acid does not occur instantaneously during melt mixing. Impregnation is poor, resulting in poor dispersion of the glass fibers and a non-uniform molding material. Furthermore, as the melt viscosity increases, the kneading resistance increases, resulting in greater damage to the glass fibers, which not only impairs the mechanical and thermal properties of the molded product, but also causes large variations in properties locally. Depending on the intended use of the molded product, this often results in a fatal defect that makes the molded product unsuitable for actual use. The present inventors conducted further studies to develop a resin composition that does not cause such defects and has excellent crystallinity and mold release properties, and as a result, it was found that the mold release effect of acetylacetone metal chelate and itself alone is extremely low. The inventors have discovered that such defects can be significantly improved by using a specific small montan wax ester in combination with the montan wax ester, and have arrived at the present invention. That is, the present invention uses 5 to 200 parts by weight of glass fiber (B) and acetylacetone alkali metal chelate (C) per 100 parts by weight of polyethylene terephthalate resin (A) having an intrinsic viscosity (measured at 35°C in an orthochlorophenol solution) of 0.9 or less. 0.01 to 3 parts by weight, and the following formula
(1), (2) and (3) 50≦NV≦110 …(1) 100≦SV≦180 …(2) 10≦(SV−NV)≦100 …(3) (In the formula, NV is The present invention relates to a polyester resin composition containing 0.05 to 3 parts by weight of montan wax ester (D) that satisfies a neutralization value (SV is a saponification value). The polyethylene terephthalate resin as component (A) used in the present invention is mainly polyethylene terephthalate obtained by using terephthalic acid or its ester-forming derivative as the acid component and ethylene glycol or its ester-forming derivative as the glycol component. However, a part of the terephthalic acid component or ethylene glycol component may be replaced with a copolymer component. Such copolymerization components include, for example, isophthalic acid, phthalic acid; alkyl-substituted phthalic acids such as methyl terephthalic acid and methyl isophthalic acid;
- Diphenylcarboxylic acids such as naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, and 1,5-naphthalene dicarboxylic acid; aromatics such as diphenoxyethane carboxylic acids such as 4,-4'-diphenoxyethane dicarboxylic acid; Group dicarboxylic acids;
Aliphatic or alicyclic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid, decadicarboxylic acid, cyclohexanedicarboxylic acid, etc.; trimethylene glycol, tetramethylene glycol, hexamethylene glycol, neopentyl glycol, diethylene glycol, 1 ,4
- Aliphatic or alicyclic diols such as cyclohexanedimethanol; dihydroxybenzenes such as hydroquinone, resorcinol, etc.; 2,2-
Bisphenols such as bis(4-hydroxydiphenyl) sulfone; aromatic diols such as ether diols obtained from bisphenols and glycols such as ethylene glycol; ε-oxycaproic acid, hydroxybenzoic acid, hydroxyl Examples include oxycarboxylic acids such as ethoxybenzoic acid. One or more of these copolymerization components can be used, and the proportion thereof is preferably 20 mol % or less based on the total dicarboxylic acid (in the case of oxycarboxylic acid, half the amount is calculated as carboxylic acid). Furthermore, a small proportion of a branching component such as a trifunctional compound such as tricarballylic acid, trimellisic acid, trimellitic acid, or a tetrafunctional ester-forming compound such as pyromellitic acid may be copolymerized with the above-mentioned polyethylene terephthalate. These polyesters may be used alone or in combination of two or more. The intrinsic viscosity of the polyethylene terephthalate resin used in the present invention is preferably 0.9 or less when measured at 35° C. using an orthochlorophenol solvent, and more preferably in the range of 0.4 to 0.9, particularly 0.45 to 0.8. When polyethylene terephthalate resin with an intrinsic viscosity exceeding 0.9 is used, the fluidity of the composition is poor, and the resulting molded product not only loses its glossy appearance but also has large variations in its mechanical and thermal properties. So I don't like it. The glass fiber of component (B) used in the present invention is not particularly limited as long as it is generally used for reinforcing resins. For example, a long fiber type (glass roving) or a chopped strand of short fibers can be selected for use. Further, the glass fibers may be treated with a sizing agent (eg, polyvinyl acetate, polyester sizing agent, etc.), a coupling agent (eg, silane compound, borane compound, etc.), or other surface treatment agent. Furthermore, it may be coated with a resin such as a thermoplastic resin or a thermosetting resin. Usually, long fiber type glass fibers are used by being cut into a desired length before or after blending with a resin, and this mode of use is also useful in the present invention. The amount of glass fiber added is preferably 5 to 200 parts by weight per 100 parts by weight of the polyethylene terephthalate resin. If the amount added is less than 5 parts by weight, the strength and heat resistance of the molded product will be low, and only an unsatisfactory molded product can be obtained. If the amount exceeds 200 parts by weight, the melt flowability of the composition will be markedly deteriorated, making it impossible to obtain a molded product with good appearance, and the strength will reach saturation, which is not preferable. The main part of the glass fiber length in the composition is 0.2mm.
It is preferable to use a material having a length of at least 100%. The alkali metals constituting the acetylacetone alkali metal chelate of component (C) used in the present invention include lithium, sodium, potassium,
Examples include rubidium, cesium, and francium, and among these, lithium, sodium, and potassium are particularly preferred. Such acetylacetone alkali metal chelates can be prepared by conventional methods (e.g. Organic Syntheses,
Collective Volume IV, page 869, Johr Wileye
Sons, Inc.). These chelate compounds act specifically as crystal nucleating agents for polyethylene terephthalate resin and have great effects. Furthermore, in combination with montan wax ester, component (D), which will be described later, an excellent mold release effect is exhibited. The amount of acetylacetone metal chelate is based on 100 parts by weight of polyethylene terephthalate resin.
0.01 to 3 parts by weight is desirable. When this amount is less than 0.01 parts by weight, there is almost no effect as a crystal nucleating agent, while when it is used in an amount exceeding 3 parts by weight, the effect as a crystal nucleating agent increases. On the contrary, this is not preferable because it results in inhibiting the effect of preventing the molecular weight reduction of the polyethylene terephthalate resin according to the present invention. The montan wax ester of component (D) used in the present invention means a partial ester compound of montan wax acid. Here, montan wax acid is a mixture of saturated aliphatic monocarboxylic acids mainly having a chain length of 20 to 32 carbon atoms, and a common example is so-called montan wax obtained by refining lignite. ) is oxidized with an oxidizing agent such as a chromic acid mixture. The above-mentioned montan wax ester is produced by converting the montanic acid into a monohydric or dihydric alcohol, particularly a dihydric alcohol having 2 to 4 carbon atoms in the alkylene group, according to the following formulas (1), (2) and (3). It is partially esterified to satisfy the following. 50≦NV≦110 …(1) 100≦SV≦180 …(2) 10≦(SV−NV)≦100 …(3) (Here, NV is neutralization value and SV is saponification value ) The above neutralization value and saponification value are values measured according to JISK3341. Unlike montanic acid, montan wax ester does not significantly lower the molecular weight of polyethylene terephthalate resin, and when combined with the acetylacetone alkali metal complex salt of component (C), exhibits an excellent mold release effect. The NV and SV of the montan wax ester greatly affect the mold releasability and physical property deterioration of the composition, particularly the molecular weight deterioration. As a condition for expressing the mold release effect, it is necessary that NV and SV each be within a certain range as shown in the above formulas (1) and (2), but in addition, (SV - NV) must be within a certain range. The value must satisfy equation (3). When the (SV-NV) value is less than 10, the molecular weight of the polyethylene terephthalate resin decreases significantly, while when it exceeds 100, the release effect becomes extremely weak.
The preferred range of (SV-NV) value is 20-80. The amount of Montan wax ester added is 0.05 to 100 parts by weight of polyethylene terephthalate resin.
It is 3 parts by weight. If the amount added is less than 0.05 parts by weight, there is almost no effect as a mold release agent, while if it is used in excess of 3 parts by weight, the effect as a mold release agent reaches saturation and increases. Not only is this not possible, but it is also impractical because it promotes a decrease in the molecular weight of the polyethylene terephthalate resin. The resin composition of the present invention is produced by blending polyethylene terephthalate resin, glass fiber, acetylacetone alkali metal complex salt, and montan wax ester. Any method can be used for the blending method.
Generally, it is preferable to disperse these components more uniformly, for example, by mixing all of them simultaneously or separately using a blender, kneader, roll, extruder, etc., to homogenize them, or by simultaneously dispersing some of the mixed components. Alternatively, they are mixed separately, for example, in a blender, kneader, roll, extruder, etc., and the remaining components are further mixed in these mixers or extruders,
Homogenization methods can be used. Furthermore,
The montan wax ester is preferably kneaded into the polyethylene terephthalate resin, and it is preferable to melt and mix the two in advance. The most common method is to melt and knead a previously dry-blended composition in a heated extruder to homogenize it, extrude it into wires, and then cut it into desired lengths and granulate it. . The molding composition thus prepared is normally kept in a sufficiently dry state before being charged into the hopper of a molding machine and subjected to molding. Other methods include, for example, adding and mixing other components during the production of polyethylene terephthalate, before the polycondensation, after the polycondensation, or during the polycondensation. Glass fibers may be dry blended without being melt-kneaded with other components in an extruder in order to prevent the glass fibers from shattering as much as possible during kneading and to improve workability during composition production. For example, a composition obtained by mixing glass fiber-free polyethylene terephthalate granules produced in an extruder with a predetermined amount of glass chopped strands or a pre-prepared glass fiber-rich thermoplastic resin is placed in a molding machine hopper. It can also be used for molding. Pigments and other compounding agents may be added to the composition of the present invention in the desired amount. Examples of such compounding agents include flame retardants such as halogen-containing compounds such as brominated biphenyl ether, brominated bisphenol-A diglycidyl ether, and polycarbonate oligomers produced from brominated bisphenol-A; red phosphorus; Phosphorus compounds such as triphenyl phosphate; phosphorus-nitrogen compounds such as phosphonic acid amide; flame retardant aids such as antimony trioxide and zinc borate; inorganic substances as nucleating agents that further promote crystallization, such as alkaline earth. Metal oxides such as metal carbonates (e.g. calcium carbonate, magnesium carbonate, etc.), sulfates (e.g. calcium sulfate, etc.), titanium oxide, aluminum oxide, zinc oxide, etc., talc, graphite,
Examples include aluminum silicate and clay. Furthermore, inorganic fillers such as silica, mica, asbestos, glass fuchs, glass powder, potassium titanate, carbon fiber, feldspar, etc., as well as other stabilizers, colorants, antioxidants, lubricants, ultraviolet absorbers, and antistatic agents. It can also be added. Also, in small proportions, other thermoplastic resins such as styrene resins, acrylic resins, polyethylene, polypropylene, fluorine resins, polyamide resins, polycarbonate resins, polysulfones, etc.; thermosetting resins such as phenolic resins, melamine resins, unsaturated polyester resins , silicone resins, etc.; and soft thermoplastic resins such as ethylene-vinyl acetate copolymers, polyester elastomers, ethylene-propylene terpolymers, etc. may also be added. The resin composition of the present invention can be molded very easily by a conventional method using a general thermoplastic resin molding machine. There is no need to particularly heat the mold temperature, but when molding is performed in a mold preheated to 120℃ to 150℃, the crystallization rate is accelerated by the effect of the nucleating agent, resulting in more homogeneous molding both inside and outside. This is preferable because it allows you to obtain products. The resin composition of the present invention has excellent moldability (particularly embedding property, crystallinity, and mold releasability), and can be molded into molded products with high productivity, and the resulting molded products have excellent gloss and no whitening phenomenon. Not only does this prevent the phenomenon of white powdery matter adhering to the surface of the molded product, giving it an excellent appearance, but it also suppresses a decrease in the molecular weight of the resin, so it exhibits the desired mechanical and thermal properties. Can be done. The present invention will be further explained below with reference to Examples. In the examples, the intrinsic viscosity of the polyethylene terephthalate resin and polybutylene terephthalate resin is the value measured in orthochlorophenol at 35°C.
Moreover, the mold releasability and static strength during molding are values measured by the following method unless otherwise specified. Mold releasability: After drying the sample molding pellets with hot air at 140℃ for 4 hours, they were immediately put into a 5-ounce injection molding machine at a cylinder temperature of 275℃ and an injection pressure of 800Kg/cm ² mold temperature.
A box-shaped molded product (external dimensions: bottom 128 mm x 68 mm, height 39 mm, wall thickness 2 mm) is molded under the molding conditions of 140℃, cooling time 25 seconds, and total cycle 40 seconds.The molding machine used for this test was equipped with an extrusion plate. A dynamic strain measuring device (Strong Gauge) is installed between the extruder pin and the extrusion pin to measure the force required to release the molded product (referred to as mold release force) after one cycle of molding is completed and the mold is opened. ) can be detected by a dynamic strain measuring device via the mold knockout pin and the molding machine extrusion pin.Therefore, the degree of difficulty in mold releasability can be indicated by the value of the mold release force. However, in reality, when the mold is opened without any charge of resin in the mold, the force detected by the dynamic strain measuring instrument is 0.5 kg, which is necessary to release the molded product itself. The force is (measured value - 0.5) Kg - weight. This value is called the mold release index and is used as a value representing the degree of mold release property. In other words, the smaller the mold release index is, the better the mold release property is. The measured value of the mold release index is the value obtained by subtracting 0.5 from the average value (unit: kg - weight) of the mold release force measured for 10 shots from the 11th shot to the 20th shot after the start of continuous molding. Static strength: After drying the sample molding pellet with hot air at 140℃ for 4 hours, a test piece mold for measuring physical properties was attached to a 5-ounce injection molding machine, and the cylinder temperature was
Test pieces were molded under the following conditions: 280° C., mold temperature 140° C., injection pressure 1000 Kg/cm ² , cooling time 20 seconds, and total cycle 35 seconds. Using this test piece, a tensile test (ASTM D-638) and a bending test (ASTM D-
790) was carried out. Examples 1 and 2 and Comparative Examples 1 to 5 70 parts by weight of polyethylene terephthalate resin with an intrinsic viscosity of 0.64 dried at 120°C for 5 hours, and a length of 3
30 parts by weight of glass chopped strands of 30 mm in diameter and various mold release agents shown in Table 1 were added in the parts by weight shown in Table 1, and mixed uniformly using a V-type blender. The resulting mixture was melt-kneaded in a 65 mmφ extruder at a barrel temperature of 280°C, extruded from a die, and the extruded slet was cooled and cut to obtain a beret for molding. Next, 0.1 part by weight of sodium acetylacetonate powder was added to 100 parts by weight of the pellets, which were further mixed uniformly in a V-type blender and then subjected to molding. Table 1 summarizes the measurement results of the mold releasability, intrinsic viscosity, and static strength of the molded products during molding of each pellet. The molded products obtained here all have excellent surface appearance and are equally shiny and beautiful, but the mold releasability and static strength differ depending on the mold release agent used and the amount added. The results were obtained. WAX-S (manufactured by Hoechst AG, West Germany), which is the mold release agent used in Comparative Example 1, is the montan wax acid described herein. When this WAX-S is used, the mold releasability is extremely good, but it has the disadvantage that it significantly lowers the intrinsic viscosity of the molded product, thereby reducing the static strength of the molded product. On the other hand, when WAX-S is reacted with 1,3-butanediol to esterify some of the carboxyl groups and used as a mold release agent, the degree of esterification has a large effect on mold releasability and static strength. Change. That is, the embodiments of Examples 1 and 2 were partially esterified according to the present invention, and were esterified with 0.35 equivalent and 0.5 equivalent of 1,3-butanediol relative to WAX-S, respectively. It can be seen that when these esterified products are used as mold release agents, both mold releasability and static strength are good.

[Table] However, in the embodiment of Comparative Example 2, in which WAX-S was partially esterified by reacting with 0.83 equivalents of 1,3-butanediol, no decrease in static strength was observed, but the mold releasability was extremely poor, and molding The product was greatly deformed due to the pressure of the mold dowel pin during demolding. Comparative Example 3 is an embodiment in which the esterified product of WAX-S used in Example 1 was added. In this case, there was no problem with mold releasability, but a significant decrease in static strength was observed. Further, Comparative Examples 4 and 5 are examples in which stearic acid and esterified stearic acid with 0.7 equivalent of 1,3-butanediol were used as mold release agents. However, in both cases, the releasability was extremely poor. In particular, in systems to which stearic acid is added, the intrinsic viscosity of the molded product decreases and the static strength is also low. Comparative Examples 6 and 7 70 parts by weight of polybutylene terephthalate resin with an intrinsic viscosity of 0.90 dried at 130°C for 3 hours, and a length of 3
30 parts by weight of glass chopped strands of mm and 0.3 parts by weight of 1,3-butanediol partial esterified product of WAX-S used in Comparative Example 1 or WAS-S used in Comparative Example 2 were added and uniformly mixed in advance. Mixed and blended. The obtained mixture was kneaded and extruded using a 30 mmφ vented extruder while degassing from the vent part. The barrel temperature during extrusion was 270°C, and the average discharge rate was about 2 kg/hv. The extrudate was cut with a cutter after passing through cooling water, and 0.1 part by weight of sodium acetylacetonate powder was added per 100 parts by weight of pellets for molding, and further V
After mixing evenly with a mold blender, reduce the temperature to 250℃.
It was molded under the same molding conditions as in Example 1, except that the temperature was set at .degree. C., and the mold releasability and static strength were measured. The measurement results are shown in Table-2.
According to Table 2, the cases of polybutylene terephthalate resin are also shown in Comparative Example 1 and Comparative Example 2.

[Table] As with polyethylene terephthalate resin, it can be seen that the static strength decreases when WAX-S is used. However, the major difference between the two is that when an esterified product of WAX-S is added, this compound has an extremely low mold release effect on polyethylene terephthalate resin, but a large mold release effect on polybutylene terephthalate resin. It can be seen that this occurs. In other words, when the Montan wax according to the present invention has a different esterification rate, the influence on the mold release properties of the composition is significantly different between polyethylene terephthalate resin and polyethylene terephthalate resin even among terephthalate esters that belong to the same family of polymers. Ru. Therefore, the neutralization value and saponification value of the montan wax acid ester specified in the present invention are applicable only to polyethylene terephthalate resin. Comparative Example 8 The static strength of a molded product obtained by molding the pellets obtained in Example 1 without adding sodium acetylacetonate powder was a tensile strength of 1560 Kg/cm ² .
Although the bending strength was high, 2180 Kg/cm ² , the mold releasability during molding was extremely poor, with a mold release index of 36, and the molded product was significantly deformed upon mold release. Furthermore, the appearance of the molded product was less glossy than in Example 1, and the resin had a marked flow pattern, giving it a poor appearance. Example 3 100 parts by weight of polyethylene terephthalate with an intrinsic viscosity of 0.72, dried at 120°C for 8 hours, fiber length 3 mm
42 parts by weight of glass chopped strands, WAX
-0.3 parts by weight of an esterified product obtained by partially esterifying S with 0.5 equivalents of n-butanol and 0.07 parts by weight of sodium acetylacetonate are mixed uniformly in a tumbler and then extruded and kneaded under the same conditions as Example 1 for molding. Got pellets. The WAX-S esterified product used as a mold release agent had a neutralization value of 65 and a saponification value of 143. The appearance of molded products made using the pellets was glossy and extremely good. Moreover, the measurement results of mold release index and static strength are as follows. Mold release index: 13Kg/heavy Tensile strength: 1510Kg/cm ² Bending strength: 2060Kg/cm ² Flexural modulus: 97000Kg/cm ² Example 4 100 parts by weight of polyethylene terephthalate with an intrinsic viscosity of 0.72, dried at 120°C for 8 hours, Fiber length 3mm
14 parts by weight of glass chopped strands, talc
Esterified product (neutralization value 69,
Saponification value: 153) 0.3 parts by weight were uniformly mixed in advance in a V-type blender, and then extrusion kneaded under the same conditions as in Example 1 to obtain a molding pallet. As a result of molding using the pellets, the mold releasability during molding was extremely good and no problems occurred during molding. Furthermore, the appearance of the obtained molded product was excellent in gloss and had a beautiful surface condition. The measurement results of the mold release index during molding and the static strength of the molded product are as follows. Mold release index: 8Kg/heavy Tensile strength: 980Kg/cm ² Bending strength: 1420Kg/cm ²

Claims (1)

[Claims] 1. Intrinsic viscosity (35 in orthochlorophenol solution)
(measured at °C) 0.9 or less per 100 parts by weight of polyethylene terephthalate resin (A), 5 to 200 parts by weight of glass fiber (B), acetylacetone alkali metal chelate (C)
0.01 to 3 parts by weight, and the following (1), (2) and (3) 50≦NV≦110 …(1) 100≦SV≦180 …(2) 10≦(SV−NV)≦100 … (3) (However, in the formula, NV represents the neutralization value and SV represents the saponification value.) Montan wax ester (D) 0.05 to 3
A polyester resin composition formed by blending parts by weight.