WO2013125453A1

WO2013125453A1 - Polyester resin composition used in reflective plate for surface-mounted led

Info

Publication number: WO2013125453A1
Application number: PCT/JP2013/053638
Authority: WO
Inventors: 戸川　惠一朗; 万紀木南; 順一中尾
Original assignee: 東洋紡株式会社
Priority date: 2012-02-24
Filing date: 2013-02-15
Publication date: 2013-08-29
Also published as: JP6048833B2; JPWO2013125453A1; TW201345971A

Abstract

The present invention is a polyester resin composition including: a copolymer polyester resin (A); a titanium oxide (B); at least one type of reinforcing material (C) selected from a group comprising a fibrous reinforcing material and a needle-like reinforcing material; and a non-fibrous or non-needle-like filler (D). The polyester resin composition contains the titanium oxide (B) in the amount of 0.5-100 parts by mass, the reinforcing material (C) in the amount of 0-100 parts per mass, and the non-fibrous or non-needle-like filler (D) in the amount of 0-50 parts per mass, relative to 100 parts per mass of the copolymer polyester resin (A). The present invention is capable of providing the polyester resin composition used in a reflective plate for a surface-mounted LED, wherein the copolymer polyester resin (A) has a 4,4'-biphenyldicarboxylic acid, an acid component comprising other dicarboxylic acids, and a glycol component as the constituent components thereof, and a fusion point of at least 280°C, said polyester resin composition being suitable for reflective plates for surface-mounted LEDs and having excellent heat resistance, excellent moldability during injection molding, excellent low water absorbability, and excellent surface reflectivity.

Description

Polyester resin composition used for reflector for surface mount LED

The present invention relates to a polyester resin composition suitable for use in a reflector for a surface mount LED having excellent moldability, fluidity, dimensional stability, low water absorption, solder heat resistance, surface reflectance, and the like. Furthermore, this invention relates to the polyester resin composition for LED suitable for using for the reflector for surface mount type LEDs which is excellent in gold / tin solder heat resistance, light resistance, and low water absorption.

In recent years, LEDs (light-emitting diodes) are used for lighting fixtures, optical elements, mobile phones, backlights for liquid crystal displays, automobile console panels, traffic lights, etc. by utilizing features such as low power consumption, long life, high brightness, and miniaturization. It is applied to display boards. In applications where design and portability are important, surface mounting technology is used to achieve lightness, thinness, and miniaturization.

A surface-mounted LED is generally composed of a light-emitting LED chip, a lead wire, a reflector that also serves as a case, and a sealing resin. In order to join the entire component mounted on an electronic board with lead-free solder In addition, each component must be formed of a material that can withstand the soldering reflow temperature of 260 ° C. The melting point (melting peak temperature) of the material is required to be 280 ° C. or higher. In particular, regarding the reflector, in addition to these heat resistances, surface reflectivity for efficiently extracting light and durability against heat and ultraviolet rays are required. From this point of view, various heat-resistant plastic materials such as ceramics, semi-aromatic polyamides, liquid crystal polymers, and thermosetting silicones have been studied. Among them, high refractive fillers such as titanium oxide are dispersed in semi-aromatic polyamides and polyesters. The resin made has a good balance of mass productivity, heat resistance, surface reflectance, etc., and is most commonly used. Recently, with the generalization of LEDs, it is necessary to further improve the workability and reliability of the reflector, and long-term heat-resistant coloring and light resistance are required to be improved.

For example, Patent Documents 1 and 2 have been proposed as polyester resin compositions for LED reflectors.
In Patent Documents 1 and 2, (a) i) terephthalic acid residues 70 to 100 mol%; ii) aromatic dicarboxylic acid residues 0 to 30 mol% having 20 or less carbon atoms; and iii) fats having 16 or less carbon atoms A dicarboxylic acid component comprising from 0 to 10 mol% of an aromatic dicarboxylic acid residue; and (b) i) a 2,2,4,4-tetramethyl-1,3-cyclobutanediol residue from 1 to 99 mol%; and ii) Disclosed is a glycol component containing 1-99 mol% 1,4-cyclohexanedimethanol residues (wherein the total mol% of dicarboxylic acid component is 100 mol% and the total mol% of glycol component is 100 mol%) However, although the mechanical properties tend to be good, there are problems in moldability and light resistance. Further, in Patent Document 3, (A) 100 parts by mass of a polyester resin, (B) 2 to 50 parts by mass of a phosphinate whose anion portion is a calcium salt or an aluminum salt of phosphinic acid, and (C) 0.5% of titanium dioxide. A flame-retardant polyester resin composition for a reflector of an illuminating device using a semiconductor light-emitting element as a light source, comprising: 30 parts by mass and (D) 0.01-3 parts by mass of a polyolefin resin having a polar group However, there are problems in the heat resistance, heat resistance, and light resistance of gold / tin solder. In Patent Document 4, 100 parts by mass of wholly aromatic thermotropic liquid crystal polyester, 97 to 85% by mass of titanium oxide obtained by a production method including a roasting step, 3 to 15% by mass of aluminum oxide (including hydrate) (Total of 100% by mass of both) comprising 8 to 42 parts by mass of titanium oxide particles surface-treated, 25 to 50 parts by mass of glass fibers, and 0 to 8 parts by mass of other inorganic fillers. Resin composition obtained through a melt-kneading step including a step of supplying at least a part of the glass fiber from a position 30% or more downstream with respect to the total length of the cylinder of the biaxial kneader using a shaft kneader. Although a product is disclosed, there is a problem in heat resistance and light resistance.
Patent Document 5 discloses a dry unsaturated polyester resin composition containing at least an unsaturated polyester resin, a polymerization initiator, an inorganic filler, a white pigment, a release agent, and a reinforcing material, wherein the unsaturated polyester resin is The total amount of the inorganic filler and the white pigment is in the range of 44 to 74% by mass with respect to the total amount of the composition. The proportion of the white pigment in the total amount of the inorganic filler and the white pigment is 30% by mass or more, and the unsaturated polyester resin is mixed with the unsaturated alkyd resin and the crosslinking agent. Although the unsaturated polyester resin composition for LED reflectors characterized by being is disclosed, there exists a problem in a moldability and light resistance. In addition, various polyamides have been used as surface mount LED reflectors, but there are problems with heat-resistant coloring, light resistance, and water absorption.

As described above, conventionally proposed polyesters and polyamides are used while having problems in heat-resistant coloring, light resistance and moldability.

Furthermore, in recent years, it has been actively developed for lighting applications. When considering the development of lighting applications, further cost reduction, higher power, longer life, and long-term reliability are required. Therefore, as a measure for improving the reliability, gold / tin eutectic solder having a low deterioration and a high thermal conductivity is being used instead of the conventional epoxy resin / silver paste for bonding the lead frame and the LED chip. However, since processing of gold / tin eutectic solder requires a temperature of 280 ° C. or higher and lower than 290 ° C., the resin to be used is required to have a melting point of 290 ° C. or higher in order to withstand the process. Further, even when processing gold / tin eutectic solder, the resin is required to have low water absorption in order to prevent blisters from occurring on the surface of the molded product due to moisture in the resin.

As described above, the required melting point (melting peak temperature) of the polyester resin composition used for the surface mount LED reflector is as high as 280 ° C. or higher, preferably 290 ° C. or higher, and the aromatic ring concentration is high. It is preferable. However, a polyester resin composition used for a surface mount LED reflector satisfying these conditions has not been reported so far.

Special table 2008-544030 gazette Special table 2008-54031 JP 2010-270177 A JP 2008-231368 A Japanese Patent No. 4844699

The present invention was devised in view of the above-mentioned problems of the prior art, and its purpose is moldability during injection molding, fluidity, dimensional stability, low water absorption, solder heat resistance, surface reflectance, An object of the present invention is to provide a polyester resin composition suitable for use in a surface mount LED reflector having excellent light resistance. Furthermore, an object of the present invention is to provide a high melting point that can be applied to a gold / tin eutectic soldering process and to ensure a long-term reliability, and a low water absorption for reducing swelling of a molded product due to moisture in the soldering process. Another object of the present invention is to provide a polyester resin composition suitable for use in a surface mount LED reflector that has achieved light resistance during outdoor use or long-term use.

In order to achieve the above object, the present inventor can advantageously perform injection molding and reflow soldering processes while satisfying the characteristics as an LED reflector, and further, gold / tin eutectic solder heat resistance, low water absorption As a result of intensive studies on the composition of polyester having excellent properties and light resistance, the present invention has been completed.

That is, the present invention has the following configuration.
(1) Copolyester resin (A), titanium oxide (B), at least one reinforcing material (C) selected from the group consisting of fibrous reinforcing materials and acicular reinforcing materials, and non-fibrous or non-needle Containing a filler (D), 0.5 to 100 parts by weight of titanium oxide (B), 0 to 100 parts by weight of reinforcing material (C), and 100% by weight of 100 parts by weight of the copolyester resin (A) Or non-needle-like filler (D) in a proportion of 0 to 50 parts by weight, wherein the copolymerized polyester resin (A) comprises 4,4′-biphenyldicarboxylic acid and other dicarboxylic acids A polyester resin composition for use in a reflector for a surface-mounted LED, comprising an acid component and a glycol component, each having a melting point of 280 ° C. or higher.
(2) The polyester resin composition as described in (1), wherein 30 mol% or more of all acid components constituting the copolyester resin (A) is 4,4′-biphenyldicarboxylic acid.
(3) The polyester resin as described in (1) or (2), wherein the other dicarboxylic acid constituting the copolyester resin (A) is terephthalic acid and / or 2,6-naphthalenedicarboxylic acid Composition.
(4) 30 to 90 mol% of the total acid component constituting the copolyester resin (A) is 4,4′-biphenyldicarboxylic acid, and the other dicarboxylic acid is terephthalic acid and / or 2,6-naphthalenedicarboxylic acid. It is an acid, and the glycol component is one or more selected from ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neopentyl glycol, and 1,4-butanediol. The polyester resin composition according to any one of (1) to (3).
(5) The non-fibrous or non-needle filler (D) is talc, and is contained at a ratio of 0.1 to 5 parts by mass of talc with respect to 100 parts by mass of the copolyester resin (A). The polyester resin composition according to any one of (1) to (4).
(6) The polyester resin composition according to any one of (1) to (5), wherein the solder reflow heat-resistant temperature is 260 ° C. or higher.
(7) The polyester resin composition according to any one of (1) to (6), wherein the solder reflow heat-resistant temperature is 280 ° C. or higher.
(8) The polyester resin according to any one of (1) to (7), wherein the difference between the melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) of the polyester resin composition is 40 ° C. or less. Composition.
(9) A surface-mounted LED reflector obtained by molding the polyester resin composition according to any one of (1) to (8).

In addition to high heat resistance and low water absorption, the polyester resin composition of the present invention uses a specific copolyester resin excellent in processability such as moldability during injection molding and solder heat resistance. A reflector for a surface-mounted LED that highly satisfies the required characteristics can be industrially advantageously produced.

In addition, the polyester resin composition of the present invention is adaptable to a gold / tin eutectic solder process because the main component copolymer polyester resin has a high melting point of 280 ° C. or more and excellent heat resistance. Since the aromatic ring concentration is high, characteristics such as excellent heat resistance, toughness, and light resistance, and excellent adhesion to the sealing material can be exhibited.

The polyester resin composition of the present invention is intended to be used for a reflector for a surface mount LED. The surface mount type LED includes a chip LED type using a printed wiring board, a gull wing type using a lead frame, and a PLCC type. The polyester resin composition of the present invention injection-molds all these reflectors. Can be manufactured.

The polyester resin composition of the present invention comprises a copolymerized polyester resin (A), titanium oxide (B), at least one reinforcing material (C) selected from the group consisting of a fibrous reinforcing material and an acicular reinforcing material, and Contains non-fibrous or non-needle filler (D), 0.5 to 100 parts by mass of titanium oxide (B) and 100 to 100 parts by mass of reinforcing material (C) with respect to 100 parts by mass of copolyester resin (A) A polyester resin composition containing 0 to 50 parts by mass of non-fibrous or non-needle filler (D), wherein the copolymerized polyester resin (A) is 4,4′-biphenyldicarboxylic acid It is a polyester resin composition used for a reflector for a surface-mounted LED, having an acid component composed of an acid and another dicarboxylic acid and a glycol component as constituent components and a melting point of 280 ° C. or higher.

The copolyester resin (A) is blended to realize excellent UV resistance in addition to a high melting point and low water absorption in order to impart high reliability. A) is characterized in that it comprises an acid component composed of 4,4′-biphenyldicarboxylic acid and other dicarboxylic acid and a glycol component as constituent components and has a melting point of 280 ° C. or higher. Copolymerization polyester resin (A) can make melting | fusing point 280 degreeC or more by having the following structure. The melting point of the copolyester resin (A) is preferably 290 ° C. or higher, more preferably 300 ° C. or higher, and still more preferably 310 ° C. or higher. The upper limit of the melting point of the copolyester resin (A) is not particularly set, but is 340 ° C. or lower due to the limitation of the raw material components that can be used. The melting point is measured by the method described in the Examples section below.

The copolymerized polyester resin (A) preferably contains 4,4′-biphenyldicarboxylic acid in an amount of 30 mol% or more, more preferably 4,4′-biphenyldicarboxylic acid in an amount of 50 mol% or more, still more preferably. Is 60 mol% or more, particularly preferably 63 mol% or more, and most preferably 70 mol% or more. If 4,4′-biphenyldicarboxylic acid is less than 30 mol% of the total acid component, moldability, solder heat resistance, and light resistance tend to be lowered. The amount of 4,4′-biphenyldicarboxylic acid is preferably 90 mol% or less of the total acid component. If it exceeds 90 mol%, the melting point of the polyester resin becomes too high, and the setting of the polymerization conditions tends to be difficult.
Other dicarboxylic acids are aromatic dicarboxylic acids such as terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenoxyethanedicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, and 4,4′-diphenyl ketone dicarboxylic acid. Aliphatic dicarboxylic acids such as acid, adipic acid, sebacic acid, succinic acid, glutaric acid and dimer acid, hexahydroterephthalic acid, hexahydroisophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1 , 4-cyclohexanedicarboxylic acid and the like, and among them, terephthalic acid, 2,6-naphthalenedicarboxylic acid, or a mixture thereof is preferable from the viewpoint of polymerizability, cost, and heat resistance. . Also, polyoxycarboxylic acids such as p-oxybenzoic acid and oxycaproic acid, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, biphenylsulfonetetracarboxylic acid, biphenyltetracarboxylic acid, and anhydrides thereof You may use together. The acid component constituting the copolymerized polyester resin (A) is preferably a total of 4,4′-biphenyldicarboxylic acid and other dicarboxylic acids, preferably 80 mol% or more, more preferably 90 mol% or more, and 95 mol%. The above is more preferable, 97 mol% or more is particularly preferable, and it may be 100 mol%.

Examples of the glycol component of the copolyester resin (A) include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butylene glycol, 1,2-butylene glycol, 1, 3-butylene glycol, 2,3-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2 -Cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, 3-methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 2-methyl-1,3-propa Diol, 2-ethyl-1,3-propanediol, neopentyl glycol, 2-ethyl-2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2-methyl-2 N-butyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2-di-n-butyl-1,3-propanediol, 2-ethyl- 2-n-hexyl-1,3-propanediol, 2,2-di-n-hexyl-1,3-propanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol , Aliphatic glycols such as triethylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, polypropylene glycol, Droquinone, 4,4'-dihydroxybisphenol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-bis (β-hydroxyethoxyphenyl) sulfone, bis (p-hydroxyphenyl) ether, bis (p- Examples include aromatic glycols such as hydroxyphenyl) sulfone, bis (p-hydroxyphenyl) methane, 1,2-bis (p-hydroxyphenyl) ethane, bisphenol A, and alkylene oxide adducts of bisphenol A. Among these, one or two selected from ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neopentyl glycol, and 1,4-butanediol are considered due to heat resistance, polymerizability, molding, cost, and the like. A mixture of species or more is preferred. More preferably, it is at least one selected from ethylene glycol and 1,4-butanediol. In addition, when ethylene glycol is used for the glycol component, diethylene glycol may be by-produced during the production of the copolymer polyester resin (A) to become a copolymer component. In this case, diethylene glycol by-produced is about 1 to 5 mol% with respect to ethylene glycol incorporated in the copolymer polyester resin, although it depends on the production conditions. Moreover, you may use together polyhydric polyols, such as a trimethylol ethane, a trimethylol propane, glycerol, and a pentaerythritol.

When ethylene glycol is used as the glycol component of the copolyester resin (A), the amount of 4,4′-biphenyldicarboxylic acid is preferably 63 mol% or more, preferably 70 mol% or more. Is more preferable. Further, in this case, in order to achieve a more desirable high melting point, it is more preferable that 4,4′-biphenyldicarboxylic acid is 75 mol% or more as an acid component, and 80 mol% or more is particularly preferable.

Further, metal salts such as 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5- [4-sulfophenoxy] isophthalic acid, or 2-sulfo-1,4-butanediol, 2,5 -A dicarboxylic acid or diol containing a sulfonic acid metal base such as a metal salt such as dimethyl-3-sulfo-2,5-hexanediol may be used in the total acid component or in a range of 20 mol% or less of the total diol component. Good.

Although it does not specifically limit as a catalyst used when manufacturing copolyester resin (A), It is preferable that at least 1 type of compound chosen from the compound of Ge, Sb, Ti, Al, Mn, or Mg is used. . These compounds are added to the reaction system as powders, aqueous solutions, ethylene glycol solutions, ethylene glycol slurries and the like.

Further, as stabilizers, phosphoric acid, phosphoric acid esters such as polyphosphoric acid and trimethyl phosphate, phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphonous acid compounds, phosphinic acid compounds, phosphine compounds It is preferable to use at least one phosphorus compound selected from the group consisting of:

The acid value of the copolyester resin (A) is preferably 1 to 40 eq / ton. When the acid value exceeds 40 eq / ton, light resistance tends to decrease. On the other hand, when the acid value is less than 1 eq / ton, the polycondensation reactivity tends to decrease and the productivity tends to deteriorate.

The intrinsic viscosity (IV) of the copolyester resin (A) is preferably 0.10 to 0.70 dl / g, more preferably 0.20 to 0.65 dl / g, still more preferably 0.25 to 0.60 dl / g.

The copolymerized polyester resin (A) is present in a proportion of 25 to 90% by mass, preferably 40 to 75% by mass in the polyester resin composition of the present invention. When the proportion of the copolymerized polyester resin (A) is less than the above lower limit, the mechanical strength becomes low, and when it exceeds the above upper limit, the blending amount of titanium oxide (B) and the reinforcing material (C) is insufficient, and the desired amount It becomes difficult to obtain the effect.

Titanium oxide (B) is blended to increase the surface reflectance of the reflector. For example, rutile type and anatase type titanium dioxide (TiO ₂ ) and titanium monoxide produced by the sulfuric acid method and the chlorine method. (TiO), dititanium trioxide (Ti ₂ O ₃ ) and the like can be mentioned, and rutile type titanium dioxide (TiO ₂ ) is particularly preferably used. The average particle diameter of titanium oxide (B) is generally in the range of 0.05 to 2.0 μm, preferably 0.15 to 0.5 μm, and may be used alone or may have different particle diameters. Titanium may be used in combination. The titanium oxide component concentration is 90% or more, preferably 95% or more, and more preferably 97% or more. In addition, the titanium oxide (B) may be one that has been surface-treated with a metal oxide such as silica, alumina, zinc oxide, zirconia, a coupling agent, an organic acid, an organic polyhydric alcohol, or siloxane. it can.

The proportion of titanium oxide (B) is 0.5 to 100 parts by mass, preferably 10 to 80 parts by mass with respect to 100 parts by mass of the copolyester resin (A). If the ratio of titanium oxide (B) is less than the above lower limit, the surface reflectivity is lowered, and if it exceeds the upper limit, molding processability may be lowered, such as a significant decrease in physical properties and fluidity.

The reinforcing material (C) is blended in order to improve the moldability of the polyester resin composition and the strength of the molded product, and uses at least one selected from a fibrous reinforcing material and an acicular reinforcing material. . Examples of the fibrous reinforcing material include glass fiber, carbon fiber, boron fiber, ceramic fiber, and metal fiber. Examples of the acicular reinforcing material include potassium titanate whisker, aluminum borate whisker, zinc oxide whisker, and carbonic acid. Calcium whiskers, magnesium sulfate whiskers, wollastonite and the like can be mentioned. As glass fibers, chopped strands or continuous filament fibers having a length of 0.1 mm to 100 mm can be used. As the cross-sectional shape of the glass fiber, a glass fiber having a circular cross section and a non-circular cross section can be used. The diameter of the circular cross-section glass fiber is 20 μm or less, preferably 15 μm or less, more preferably 10 μm or less. Further, a glass fiber having a non-circular cross section is preferred from the viewpoint of physical properties and fluidity. Non-circular cross-section glass fibers include those that are substantially oval, substantially oval, or substantially bowl-shaped in a cross section perpendicular to the length direction of the fiber length, and have a flatness of 1.5 to 8. It is preferable. Here, the flatness is assumed to be a rectangle with the smallest area circumscribing a cross section perpendicular to the longitudinal direction of the glass fiber, the length of the long side of the rectangle is the major axis, and the length of the short side is the minor axis. It is the ratio of major axis / minor axis. The thickness of the glass fiber is not particularly limited, but the minor axis is about 1 to 20 μm and the major axis is about 2 to 100 μm. Further, glass fibers are preferably used in the form of chopped strands which are formed into fiber bundles and cut to a fiber length of about 1 to 20 mm. Furthermore, in order to increase the surface reflectance of the polyester resin composition, it is preferable that the difference in refractive index from the copolyester resin is large, so use a material whose refractive index is increased by changing the glass composition or surface treatment. It is preferable to do.

The proportion of the reinforcing material (C) is 0 to 100 parts by mass, preferably 5 to 100 parts by mass, and more preferably 10 to 60 parts by mass with respect to 100 parts by mass of the copolyester resin (A). The reinforcing material (C) is not an essential component, but the proportion of 5 parts by mass or more is preferable because the mechanical strength of the molded product is improved. When the ratio of the reinforcing material (C) exceeds the above upper limit, the surface reflectance and the moldability tend to be lowered.

Examples of the non-fibrous or non-needle filler (D) include reinforcing fillers, conductive fillers, magnetic fillers, flame retardant fillers, thermal conductive fillers, thermal yellowing suppression fillers, etc., according to purpose. Glass beads, glass flakes, glass balloons, silica, talc, kaolin, mica, alumina, hydrotalcite, montmorillonite, graphite, carbon nanotubes, fullerene, indium oxide, tin oxide, iron oxide, magnesium oxide, aluminum hydroxide, Magnesium hydroxide, calcium hydroxide, red phosphorus, calcium carbonate, magnesium acetate, lead zirconate titanate, barium titanate, aluminum nitride, boron nitride, zinc borate, barium sulfate, and non-acicular wollastonite, titanium Potassium oxide, aluminum borate, Magnesium, zinc oxide, calcium carbonate, and the like. These fillers may be used not only alone but also in combination of several kinds. Among these, talc is preferable because it has an effect of accelerating crystallization and improves moldability. The addition amount of the filler may be selected as an optimum amount, but it is possible to add up to 50 parts by mass with respect to 100 parts by mass of the copolyester resin (A), but the mechanical strength of the resin composition In view of the above, 0.1 to 20 parts by mass is preferable, and 1 to 10 parts by mass is more preferable. When talc is used, it is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 3 parts by mass with respect to 100 parts by mass of the copolyester resin (A). In order to improve the affinity with the copolyester resin, the fibrous reinforcing material and filler are preferably used after being treated with an organic treatment or a coupling agent, or in combination with a coupling agent at the time of melt compounding. As the coupling agent, any of a silane coupling agent, a titanate coupling agent, and an aluminum coupling agent may be used, and among them, an aminosilane coupling agent and an epoxy silane coupling agent are particularly preferable. .

In the polyester resin composition of the present invention, various additives of conventional polyester resin compositions for LED reflectors can be used. Additives include stabilizers, impact modifiers, flame retardants, mold release agents, slidability improvers, colorants, fluorescent brighteners, plasticizers, crystal nucleating agents, thermoplastic resins other than polyester, and the like. .

Stabilizers include organic antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, heat stabilizers, light stabilizers such as hindered amines, benzophenones, and imidazoles. Examples include ultraviolet absorbers, metal deactivators, and copper compounds. Copper compounds include cuprous chloride, cuprous bromide, cuprous iodide, cupric chloride, cupric bromide, cupric iodide, cupric phosphate, cupric pyrophosphate, Copper salts of organic carboxylic acids such as copper sulfide, copper nitrate, and copper acetate can be used. Further, as a component other than the copper compound, an alkali metal halide compound is preferably contained. Examples of the alkali metal halide compound include lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, bromide. Examples thereof include sodium, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, potassium iodide and the like. These additives may be used alone or in combination of several kinds. Although the addition amount of a stabilizer should just select the optimal quantity, it is possible to add a maximum of 5 mass parts with respect to 100 mass parts of copolyester resin (A).

A thermoplastic resin different from the copolymerized polyester resin (A) may be added to the polyester resin composition of the present invention. For example, polyamide (PA), polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), fluororesin, aramid resin, polyetheretherketone (PEEK), polyetherketone (PEK), polyether Imide (PEI), thermoplastic polyimide, polyamideimide (PAI), polyether ketone ketone (PEKK), polyphenylene ether (PPE), polyethersulfone (PES), polysulfone (PSU), polyarylate (PAR), polyethylene terephthalate, Polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate (PC), polyoxymethylene (POM), polypropylene (PP), polyethylene (PE) Polymethyl pentene (TPX), polystyrene (PS), polymethyl methacrylate, acrylonitrile - styrene copolymer (AS), acrylonitrile - butadiene - styrene copolymer (ABS) and the like. These thermoplastic resins can be blended in a molten state by melt kneading. However, the thermoplastic resin may be made into a fiber or particle and dispersed in the polyamide resin composition of the present invention. An optimum amount of the thermoplastic resin may be selected, but a maximum of 50 parts by mass can be added to 100 parts by mass of the copolyester resin (A).

Impact modifiers include ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene- Polyolefin resins such as methacrylic acid ester copolymer, ethylene vinyl acetate copolymer, styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene -Styrene copolymer (SIS), vinyl polymer resin such as acrylate copolymer, polybutylene terephthalate or polybutylene naphthalate as hard segment, polytetramethylene glycol or polycaprolactone or poly Polyester block copolymer in which the turbo sulfonate diol as a soft segment, a nylon elastomer, urethane elastomer, acrylic elastomer, silicone rubber, fluorinated rubber, and the like polymer particles having a core-shell structure constituted from two different polymers. The addition amount of the impact modifier may be selected as an optimum amount, but it is possible to add a maximum of 30 parts by mass with respect to 100 parts by mass of the copolyester resin (A).

When a thermoplastic resin other than the copolymerized polyester resin (A) and an impact resistance improving material are added to the polyester resin composition of the present invention, a reactive group capable of reacting with the polyester is copolymerized. Preferably, the reactive group is a group capable of reacting with a hydroxyl group and / or a carboxyl group which is a terminal group of the polyester resin. Specific examples include an acid anhydride group, an epoxy group, an oxazoline group, an amino group, and an isocyanate group. Among these, an epoxy group and an isocyanate group are most excellent in reactivity. There is also a report that the thermoplastic resin having a reactive group that reacts with the polyester resin is finely dispersed in the polyester and finely dispersed, so that the distance between the particles is shortened and the impact resistance is greatly improved.

As a flame retardant, a combination of a halogen flame retardant and a flame retardant aid is good. As a halogen flame retardant, brominated polystyrene, brominated polyphenylene ether, brominated bisphenol type epoxy polymer, brominated styrene maleic anhydride Polymers, brominated epoxy resins, brominated phenoxy resins, decabromodiphenyl ether, decabromobiphenyl, brominated polycarbonate, perchlorocyclopentadecane, brominated cross-linked aromatic polymers, etc. are preferred. Examples include layered silicates such as antimony, antimony pentoxide, sodium antimonate, zinc stannate, zinc borate, and montmorillonite, fluorine-based polymers, and silicones. Among these, from the viewpoint of thermal stability, the halogen flame retardant is preferably a combination of dibromopolystyrene and the flame retardant auxiliary is any combination of antimony trioxide, sodium antimonate, and zinc stannate. Non-halogen flame retardants include melamine cyanurate, red phosphorus, phosphinic acid metal salts, and nitrogen-containing phosphoric acid compounds. In particular, a combination of a phosphinic acid metal salt and a nitrogen-containing phosphoric acid compound is preferable. As the nitrogen-containing phosphoric acid compound, a reaction product of melamine or a melamine condensate such as melam, melem, melon and polyphosphoric acid Or a mixture thereof. As other flame retardants and flame retardant aids, addition of hydrotalcite-based compounds and alkali compounds is preferable as metal corrosion prevention for molds and the like when these flame retardants are used. The addition amount of the flame retardant may be an optimum amount, but it is possible to add a maximum of 50 parts by mass with respect to 100 parts by mass of the copolymerized polyamide resin (A).

Examples of the release agent include long chain fatty acids or esters thereof, metal salts, amide compounds, polyethylene wax, silicone, polyethylene oxide, and the like. The long chain fatty acid preferably has 12 or more carbon atoms, and examples thereof include stearic acid, 12-hydroxystearic acid, behenic acid, and montanic acid. Partial or total carboxylic acid is esterified with monoglycol or polyglycol. Or a metal salt may be formed. Examples of the amide compound include ethylene bisterephthalamide and methylene bisstearyl amide. These release agents may be used alone or as a mixture. The addition amount of the release material may be selected as an optimum amount, but a maximum of 5 parts by mass can be added to 100 parts by mass of the copolyester resin (A).

The polyester resin composition of the present invention preferably has a melting peak temperature (Tm) of 280 ° C. or higher in DSC measurement, more preferably 290 ° C. or higher, further preferably 300 ° C. or higher, particularly preferably 310 ° C. or higher. Most preferably, it is 320 degreeC or more. The upper limit of Tm of the polyester resin composition of the present invention is preferably 340 ° C. or lower for the following reason. When Tm exceeds the above upper limit, the processing temperature required for injection molding the polyester resin composition of the present invention becomes extremely high, so that the polyester resin composition decomposes during processing, and the desired physical properties and appearance are obtained. There may not be. On the other hand, when Tm is less than the above lower limit, the crystallization rate is slow, and in some cases, molding may be difficult, and further, solder heat resistance may be reduced. A Tm of 310 ° C. or higher is preferable because it satisfies the reflow solder heat resistance of 280 ° C. and can be applied to a gold / tin eutectic solder process.

Furthermore, the polyester resin composition of the present invention preferably has a difference in melting peak temperature (Tm) and cooling crystallization temperature (Tc2) of 40 ° C. or less, more preferably 35 ° C. or less, and still more preferably 30 in DSC measurement. It is below ℃. The temperature-falling crystallization temperature (Tc2) is a temperature at which crystallization starts when the temperature is lowered from a temperature 10 ° C. higher than the melting point of the copolyester resin in DSC measurement. The melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) are measured by the methods described in the Examples section below. When the difference between the melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) is 40 ° C. or less, crystallization proceeds easily, and dimensional stability and physical properties can be sufficiently exhibited. On the other hand, when the difference between the melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) exceeds 40 ° C., the LED reflector is molded in a short cycle of injection molding, so that crystallization may not proceed sufficiently. Due to molding difficulties such as insufficient mold release, or because crystallization has not been completed sufficiently, deformation and crystal shrinkage occur during heating in the subsequent process, causing problems of peeling from the sealing material and lead frame, resulting in reliability Lack of sex.

The copolymerized polyester resin (A) in the present invention has an excellent balance of low water absorption and fluidity in addition to a high melting point and moldability, and also has excellent light resistance. For this reason, the polyester resin composition of the present invention obtained from such a copolyester resin (A) has a high melting point of 280 ° C. or higher and low water absorption in the molding of a reflector of a surface-mounted LED. Thin-walled, high-cycle molding is possible.

The polyester resin composition of the present invention can be produced by blending the above-described constituent components by a conventionally known method. For example, each component is added during the polycondensation reaction of the copolyester resin (A), the copolyester resin (A) and other components are dry blended, or a twin screw type extruder is used. The method of melt-kneading each structural component can be mentioned.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In addition, the measured value described in the Example is measured by the following method.

(1) Intrinsic viscosity of copolyester resin (IV)
The viscosity was determined from the solution viscosity at 30 ° C. in a 1,1,2,2-tetrachloroethane / phenol (2: 3 weight ratio) mixed solvent.
(2) Acid value After 0.1 g of copolyester resin was dissolved in 10 ml of benzyl alcohol by heating, it was determined by titration using a solution of 0.1 N NaOH in methanol / benzyl alcohol (1/9 volume ratio). .
(3) Melting point of copolymerized polyester resin, melting peak temperature (Tm) of resin composition, cooling crystallization temperature (Tc2)
Measurements were made with a differential thermal analyzer (DSC), RDC-220, manufactured by Seiko Denshi Kogyo Co., Ltd. The temperature was raised at a rate of temperature increase of 20 ° C./min, held at 330 ° C. for 3 minutes, and then cooled from 330 ° C. to 130 ° C. at a rate of 10 ° C./min. The peak temperature of the melting peak observed when the temperature was raised was the melting point Tm, and the temperature of the crystallization peak observed when the temperature was lowered was the temperature-falling crystallization temperature (Tc2).

(4) Formability Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C., the mold temperature is set to 120 ° C., and a flat plate having a film gate length of 100 mm, width of 100 mm, and thickness of 1 mm. Injection molding was carried out using a production mold. Molding was performed at an injection speed of 50 mm / sec, a holding pressure of 30 MPa, an injection time of 10 seconds, and a cooling time of 10 seconds. The quality of the moldability was evaluated as follows.
○: A molded product can be obtained without problems.
Δ: Sprue sometimes remains in the mold.
X: The releasability is insufficient, and the molded product sticks to the mold or deforms.

(5) Solder heat resistance Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C., the mold temperature is set to 140 ° C., the length is 127 mm, the width is 12.6 mm, and the thickness is 0.8 mm. The test piece for the UL combustion test was injection molded to produce a test piece. The test piece was left in an atmosphere of 85 ° C. and 85% RH (relative humidity) for 72 hours. The specimen was heated in an air reflow furnace (AIS-20-82C manufactured by ATEC) from room temperature to 150 ° C over 60 seconds, preheated, and then heated to 190 ° C at a rate of 0.5 ° C / min. Preheating was performed. Thereafter, the temperature was raised to a predetermined set temperature at a rate of 100 ° C./min, held at the predetermined temperature for 10 seconds, and then cooled. The set temperature was increased from 240 ° C. every 5 ° C., and the highest set temperature at which the surface did not swell or deformed was defined as the reflow heat resistant temperature, which was used as an index of solder heat resistance.
A: Reflow heat resistant temperature is 280 ° C or higher. ○: Reflow heat resistant temperature is 260 ° C or higher and lower than 280 ° C. X: Reflow heat resistant temperature is lower than 260 ° C.

(6) Diffuse reflectance Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C, the mold temperature is set to 140 ° C, and a flat plate of 100mm in length, 100mm in width and 2mm in thickness is injection molded. Then, a test piece for evaluation was produced. Using this test piece, an integrating sphere manufactured by Hitachi, Ltd. was installed in a self-recording spectrophotometer “U3500” manufactured by Hitachi, Ltd., and the reflectance at wavelengths from 350 nm to 800 nm was measured. For comparison of reflectance, diffuse reflectance at a wavelength of 460 nm was obtained. Barium sulfate was used as a reference.

(7) Saturated water absorption Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C, the mold temperature is set to 140 ° C, and a flat plate of 100mm length, 100mm width and 1mm thickness is injection molded. Then, a test piece for evaluation was produced. This test piece was immersed in hot water at 80 ° C. for 50 hours, and the saturated water absorption was determined from the following equation from the weight at the time of saturated water absorption and drying.
Saturated water absorption (%) = {(weight at saturated water absorption−weight at drying) / weight at drying} × 100

(8) Fluidity Using Toshiba Machine's injection molding machine IS-100, cylinder temperature is set to 330 ° C, mold temperature is set to 120 ° C, injection pressure set value is 40%, injection speed set value is 40%, weighing is 35mm, Under the conditions of an injection time of 6 seconds and a cooling time of 10 seconds, injection molding was performed with a flow length measuring mold having a width of 1 mm and a thickness of 0.5 mm to prepare an evaluation test piece. As an evaluation of fluidity, the flow length (mm) of this test piece was measured.

(9) Adhesion of silicone Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C, the mold temperature is set to 140 ° C, and a flat plate of 100mm length, 100mm width and 2mm thickness is injection molded. Then, a test piece for evaluation was produced. One side of this test piece was coated with a silicone sealing material (Shin-Etsu Silicone Co., ASP-1110, sealing material hardness D60) to a coating thickness of about 100 μm, and after preheating at 100 ° C. for 1 hour, A curing treatment was performed at 150 ° C. for 4 hours to form a sealing material film on one side of the test piece.
Next, the adhesiveness of the sealing material film on the test piece was evaluated by a cross-cut test based on JIS K5400 (100 mm of 1 mm width crosscut).
○: No more than 10 peeling cells ×: There is peeling when forming the cells before the peeling test

(10) Light resistance Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C, the mold temperature is set to 140 ° C, and a flat plate 100mm long, 100mm wide and 2mm thick is injection molded. A test piece for evaluation was prepared. This test piece was irradiated with UV light at an illuminance of 50 mW / cm ^{2 in} an environment of 63 ° C. and 50% RH using a super accelerated weathering tester “I Super UV Tester SUV-F11”. The light reflectance at a wavelength of 460 nm of the test piece was measured before irradiation and 60 hours after irradiation. The retention rate of the light reflectance of the post-irradiation test piece relative to the light reflectance of the pre-irradiation test piece was evaluated according to the following criteria.
○: Retention rate 90% or more △: Retention rate less than 90% to 85% or more ×: Retention rate less than 85%

(11) Heat-resistant yellowing Using Toshiba Machine's injection molding machine EC-100, the cylinder temperature is set to the melting point of the resin + 20 ° C, the mold temperature is set to 140 ° C, and a flat plate of 100mm length, 100mm width and 2mm thickness is injection molded. Then, a test piece for evaluation was produced. Using this test piece, it processed for 2 hours at 150 degreeC with the hot air dryer, and confirmed yellowing visually.
○: No change △: Slightly yellow ×: Yellowish

<Synthesis Example 1>
In a 20-liter stainless steel autoclave with a stirrer, 3542 g of dimethyl 4,4′-biphenyldicarboxylate, 1409 g of high-purity dimethyl terephthalic acid, ethylene glycol in an amount 3 times the acid component, manganese acetate 2 g, and germanium dioxide 0.86 g After the transesterification, while the temperature was raised to 300 ° C. over 60 minutes, the pressure of the reaction system was gradually reduced to 13.3 Pa (0.1 Torr), and a polycondensation reaction was further performed at 310 ° C. and 13.3 Pa. . Subsequent to releasing the pressure, the resin under slight pressure was discharged into water as a strand, cooled, and then cut with a cutter to obtain a cylindrical pellet having a length of about 3 mm and a diameter of about 2 mm. The intrinsic viscosity of the obtained copolyester was 0.60 dl / g, the resin composition was 65 mol% 4,4′-biphenyldicarboxylic acid, 35 mol% terephthalic acid, ethylene glycol as determined by ¹ H-NMR measurement. Was 98.2 mol% and diethylene glycol was 1.8 mol%. Table 1 shows characteristic values of the obtained copolyester resin.

(Synthesis Examples 2 to 7)
Each copolyester resin was obtained in the same manner as in the polymerization of the copolyester resin of Synthesis Example 1 except that the amount and type of raw materials used were changed. Table 1 shows the characteristic values of the obtained copolymer polyester resins. Diethylene glycol is a by-product of condensation of ethylene glycol.
(Synthesis Example 8)
In a 20 liter stainless steel autoclave with a stirrer, 3542 g of dimethyl 4,4'-biphenyldicarboxylate, 1400 g of high purity dimethyl terephthalic acid, ethylene glycol, manganese acetate 2 g, and 0.86 g of germanium dioxide in an amount three times the acid component. After the transesterification, 8 g of high-purity terephthalic acid was added, and the temperature of the reaction system was gradually decreased to 13.3 Pa (0.1 Torr) while increasing the temperature to 300 ° C. over 60 minutes. The polycondensation reaction was carried out at 13.3 Pa. Subsequent to releasing the pressure, the resin under slight pressure was discharged into water as a strand, cooled, and then cut with a cutter to obtain a cylindrical pellet having a length of about 3 mm and a diameter of about 2 mm. The intrinsic viscosity of the obtained copolyester was 0.60 dl / g, the resin composition was 65 mol% 4,4′-biphenyldicarboxylic acid, 35 mol% terephthalic acid, ethylene glycol as determined by ¹ H-NMR measurement. Was 98.2 mol% and diethylene glycol was 1.8 mol%. Table 1 shows characteristic values of the obtained copolyester resin.

(Comparative Synthesis Example 1)
A 20-liter stainless steel autoclave with a stirrer is charged with high-purity terephthalic acid and twice its amount of ethylene glycol, and 0.3 mol% of triethylamine is added to the acid component, and water is added at 250 ° C. under a pressure of 0.25 MPa. The esterification reaction was carried out while distilling out of the system to obtain a mixture of bis (2-hydroxyethyl) terephthalate and oligomer (hereinafter referred to as BHET mixture) having an esterification rate of about 95%. To this BHET mixture, germanium dioxide (100 ppm as Ge) was added as a polymerization catalyst, and then stirred at 250 ° C. for 10 minutes under a nitrogen atmosphere at normal pressure. Thereafter, the pressure in the reaction system was gradually decreased to 13.3 Pa (0.1 Torr) while the temperature was raised to 280 ° C. over 60 minutes, and a polycondensation reaction was further performed at 280 ° C. and 13.3 Pa. Subsequent to releasing the pressure, the resin under slight pressure was discharged into water as a strand, cooled, and then cut with a cutter to obtain a cylindrical pellet having a length of about 3 mm and a diameter of about 2 mm. The obtained PET had an IV of 0.61 dl / g, and the resin composition was 100 mol% terephthalic acid, 98.0 mol% ethylene glycol, and 2.0 mol% diethylene glycol, as determined by ¹ H-NMR. It was. The characteristic values of the obtained polyester resin are shown in Table 2.

(Comparative Synthesis Examples 2 to 4)
Each polyester resin was obtained in the same manner as in the polymerization of the polyester resin of Comparative Synthesis Example 1 except that the type of raw material used was changed. Table 2 shows the characteristic values of the obtained polyester resins.

(Comparative Synthesis Example 5: Polyamide resin)
Terephthalic acid 3272.9 g (19.70 mol), 1,9-nonanediamine 2849.2 g (18.0 mol), 2-methyl-1,8-octanediamine 316.58 g (2.0 mol), benzoic acid 73 .27 g (0.60 mol), 6.5 g of sodium hypophosphite monohydrate (0.1% by weight based on the raw material) and 6 liters of distilled water were placed in an autoclave having an internal volume of 20 liters and purged with nitrogen. . The mixture was stirred at 100 ° C. for 30 minutes, and the internal temperature was raised to 210 ° C. over 2 hours. At this time, the autoclave was pressurized to 22 kg / cm ² . The reaction was continued for 1 hour, and then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours. The reaction was carried out while gradually removing water vapor and maintaining the pressure at 22 kg / cm ² . Next, the pressure was reduced to 10 kg / cm ² over 30 minutes and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.25 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a size of 2 mm or less. A white polyamide having a melting point of 310 ° C., an intrinsic viscosity [η] of 1.33 dl / g, and a terminal sealing rate of 90% was obtained by solid-phase polymerization at 230 ° C. and 0.1 mmHg for 10 hours. Obtained.

(Examples 1 to 11, Comparative Examples 1 to 5)
Using the twin screw extruder STS-35 manufactured by Coperion Co., Ltd., with the components and mass ratios described in Tables 3 and 4, the resins were melt kneaded at the melting point of the resin + 15 ° C., and Examples 1 to 11 and Comparative Examples 1 to 5 Polyester resin composition and polyamide resin composition were obtained. In Tables 3 and 4, the materials used other than the copolyester resin are as follows.
Titanium oxide (B): Ipehara Sangyo Co., Ltd. Typek CR-60, rutile TiO ₂ , average particle size 0.2 μm
Reinforcing material (C): Glass fiber (manufactured by Nittobo Co., Ltd., CS-3J-324), acicular wallast (manufactured by NYCO, NYGLOS8)
Filler (D): Talc (Micron White 5000A, Hayashi Kasei Co., Ltd.)
Mold release agent: Magnesium stearate Stabilizer: Pentaerythrityl tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (Irganox 1010, manufactured by Ciba Specialty Chemicals)

The polyester resin compositions and polyamide resin compositions obtained in Examples 1 to 11 and Comparative Examples 1 to 5 were subjected to evaluation of various properties. The results are shown in Tables 3 and 4.

From Table 3, when the melting peak temperature by DSC of the polyester resin composition is 280 ° C. or higher, it can be applied to the reflow soldering process, and when the melting peak temperature exceeds 310 ° C., the reflow heat resistant temperature is 280 ° C. or higher. Therefore, it exhibits solder heat resistance that can be applied to gold / tin eutectic soldering processes, and has excellent adhesion to sealing materials and surface reflectivity, which are important characteristics for LED applications, and moldability. It was confirmed that the fluidity, dimensional stability, low water absorption, and light resistance were excellent. On the other hand, from Table 4, all of these characteristics could not be satisfied in the comparative example. Although the polyamide resin of Comparative Example 5 has a high melting point, the reflow heat resistant temperature could not satisfy 280 ° C. or higher due to water absorption due to the amide structure.

The polyester resin composition of the present invention is not only excellent in heat resistance, moldability, fluidity, and low water absorption, but also has excellent adhesion to a sealing material in LED applications, and also has excellent light resistance. Since the copolyester resin is used, the reflector for surface mount type LED can be produced industrially advantageously while highly satisfying the required characteristics.

Claims

Copolyester resin (A), titanium oxide (B), at least one reinforcing material (C) selected from the group consisting of fibrous reinforcing materials and acicular reinforcing materials, and non-fibrous or non-acicular filling materials (D), and 0.5 to 100 parts by mass of titanium oxide (B), 0 to 100 parts by mass of reinforcing material (C), and non-fibrous or non-containing, with respect to 100 parts by mass of the copolyester resin (A) Needle-like filler (D) is a polyester resin composition containing 0 to 50 parts by weight, wherein the copolymer polyester resin (A) is an acid comprising 4,4′-biphenyldicarboxylic acid and other dicarboxylic acids A polyester resin composition used for a reflector for a surface-mounted LED, comprising a component and a glycol component as constituents and a melting point of 280 ° C. or higher.
2. The polyester resin composition according to claim 1, wherein 30 mol% or more of the total acid component constituting the copolyester resin (A) is 4,4′-biphenyldicarboxylic acid.
The polyester resin composition according to claim 1 or 2, wherein the other dicarboxylic acid constituting the copolymerized polyester resin (A) is terephthalic acid and / or 2,6-naphthalenedicarboxylic acid.
30 to 90 mol% of the total acid component constituting the copolymer polyester resin (A) is 4,4′-biphenyldicarboxylic acid, and the other dicarboxylic acid is terephthalic acid and / or 2,6-naphthalenedicarboxylic acid. The glycol component is one or more selected from ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neopentyl glycol, and 1,4-butanediol. 4. The polyester resin composition according to any one of items 1 to 3.
The non-fibrous or non-needle filler (D) is talc and is contained in a proportion of 0.1 to 5 parts by mass of talc with respect to 100 parts by mass of the copolyester resin (A). 5. The polyester resin composition according to any one of 1 to 4.
The polyester resin composition according to any one of claims 1 to 5, wherein the solder reflow heat-resistant temperature is 260 ° C or higher.
The polyester resin composition according to any one of claims 1 to 6, wherein the solder reflow heat-resistant temperature is 280 ° C or higher.
The polyester resin composition according to any one of claims 1 to 7, wherein the difference between the melting peak temperature (Tm) and the temperature-falling crystallization temperature (Tc2) of the polyester resin composition is 40 ° C or less.
A reflector for surface-mount LED, which is obtained by molding using the polyester resin composition according to any one of claims 1 to 8.