JP5915948B2 - Polyester resin and polyester resin composition for surface mounted LED reflector using the same - Google Patents

Description

  The present invention is excellent in moldability, fluidity, dimensional stability, low water absorption, solder heat resistance, surface reflectance, and the like, and further, a polyester resin excellent in gold / tin solder heat resistance, light resistance, and low water absorption. And a polyester resin composition suitable for use in a reflector for a surface-mounted LED using the same.

  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 to 5 have been proposed as polyester resin compositions for LED reflectors.

  In Patent Documents 1 and 2, (a) i) terephthalic acid residue 70 to 100 mol%; ii) aromatic dicarboxylic acid residue 0 to 30 mol% having 20 or less carbon atoms; and iii) fat having 16 or less carbon atoms. A dicarboxylic acid component comprising 0 to 10 mol% of an aromatic dicarboxylic acid residue; and (b) i) a 2,2,4,4-tetramethyl-1,3-cyclobutanediol residue of 1 to 99 mol%; and ii) A glycol component containing 1 to 99 mol% of 1,4-cyclohexanedimethanol residues (wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the glycol component is 100 mol%) Although a polyester resin is disclosed, although mechanical properties tend to be good, there are problems in moldability and light resistance.

  Moreover, in patent document 3, 2-50 mass parts of phosphinates whose (B) anion part is the calcium salt or aluminum salt of phosphinic acid with respect to 100 mass parts of (A) polyester resin, (C) Titanium dioxide 0. 5 to 30 parts by mass and (D) 0.01 to 3 parts by mass of a polyolefin resin having a polar group, and a flame retardant polyester resin composition for a reflector of an illuminating device using a semiconductor light emitting element as a light source Although a product is disclosed, there are problems in 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) It is composed of 8 to 42 parts by mass of titanium oxide particles surface-treated by adding (both of them to 100% by mass), 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 are problems in heat resistance and weather 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 resistance coloring property, light resistance, and moldability.

  Furthermore, in recent years, development for lighting applications has been actively carried out. 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 mentioned above, the polyester resin composition which fully satisfied the characteristic which can be used for the reflector for surface mount type LED has not been reported until now.

Special table 2008-544030 gazette JP 2008-54031 A 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, Excellent light resistance, and high-melting point applicable to gold / tin eutectic solder process to ensure long-term reliability, low water absorption for reducing swelling of molded products due to moisture in solder process, It is providing the polyester resin which achieved the light resistance at the time of outdoor use or long-term use, and the polyester resin composition for reflectors for surface mount type LED using the same.

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

That is, the present invention has the following configurations (1) to (11).
(1) A polyester resin comprising a dicarboxylic acid component containing 50 mol% or more of an aromatic dicarboxylic acid and a glycol component containing 15 mol% or more of 4,4′-biphenyldimethanol, having a melting point of 280 ° C. or more. Polyester resin characterized by being.
(2) The aromatic dicarboxylic acid contains at least one dicarboxylic acid selected from the group consisting of 4,4′-biphenyldicarboxylic acid, terephthalic acid, and 2,6-naphthalenedicarboxylic acid (1) The polyester resin as described in.
(3) The glycol component other than 4,4′-biphenyldimethanol constituting the polyester resin is ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neopentyl glycol, and 1,4-butane. The polyester resin according to (1) or (2), comprising at least one glycol selected from the group consisting of diols.
(4) The polyester resin according to any one of (1) to (3), wherein the difference between the melting point (Tm) of the polyester resin and the cooling crystallization temperature (Tc2) is 42 ° C. or less.
(5) The polyester resin according to any one of (1) to (4), wherein the acid value of the polyester resin is 1 to 40 eq / t.
(6) At least one reinforcing material selected from the group consisting of the polyester resin (A), titanium oxide (B), fibrous reinforcing material and acicular reinforcing material according to any one of (1) to (5). (C) and non-fibrous or non-needle-like filler (D), and 100 parts by mass of polyester resin (A), titanium oxide (B), reinforcing material (C), and non-fibrous or non-fibrous The needle-shaped filler (D) is present in a ratio of 0.5 to 100 parts by mass, 0 to 100 parts by mass, and 0 to 50 parts by mass, respectively, for use in a surface mount type LED reflector. Polyester resin composition.
(7) The non-fibrous or non-needle-like 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 polyester resin (A) ( The polyester resin composition as described in 6).
(8) Solder reflow heat-resistant temperature is 260 degreeC or more, The polyester resin composition as described in (6) or (7) characterized by the above-mentioned.
(9) Solder reflow heat-resistant temperature is 280 degreeC or more, The polyester resin composition in any one of (6)-(8) characterized by the above-mentioned.
(10) The polyester resin composition has a melting peak temperature (Tm) of 280 ° C. or higher, and a difference between the melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) is 42 ° C. or lower ( The polyester resin composition according to any one of 6) to (9).
(11) A surface mount LED reflector, which is obtained by molding using the polyester resin composition according to any one of (6) to (10).

  The polyester resin of the present invention is excellent in processability such as moldability during injection molding and solder heat resistance, in addition to high heat resistance and low water absorption. Therefore, since the polyester resin composition of the present invention uses such a polyester resin, it is possible to industrially advantageously produce a reflector for a surface mount LED that highly satisfies all necessary characteristics.

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

  The polyester resin of the present invention has characteristics suitable as a material to be used for a molded body such as a film, a sheet, an injection-molded body, and a deformed shaped body, particularly a reflector for a surface-mounted LED. Further, 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 polyester resin (A), titanium oxide (B), at least one reinforcing material (C) selected from the group consisting of a fibrous reinforcing material and a needle-shaped reinforcing material, and a non-fiber. Or a non-needle-like filler (D).

  The polyester resin (A) is blended to realize excellent UV resistance in addition to high melting point and low water absorption in order to impart high reliability, and 50 mol of aromatic dicarboxylic acid. % Dicarboxylic acid component and a glycol component containing 15 mol% or more of 4,4′-biphenyldimethanol, and has a melting point of 280 ° C. or more. The melting point of the polyester resin (A) is preferably 290 ° C. or higher, more preferably 300 ° C. or higher, and further preferably 310 ° C. or higher. Although the upper limit of melting | fusing point of a polyester resin (A) is not specifically limited, From the restriction | limiting of the raw material component which can be used, it is 340 degrees C or less. The melting point is measured by the method described in the Examples section.

  Examples of the aromatic dicarboxylic acid used as the dicarboxylic acid component of the polyester resin (A) include 4,4′-biphenyldicarboxylic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, diphenoxyethanedicarboxylic acid, 4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl ketone dicarboxylic acid, etc. are mentioned. Among the above aromatic dicarboxylic acids, 4,4′-biphenyldicarboxylic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, or a mixture thereof is preferable from the viewpoint of polymerizability, cost, and heat resistance. From the viewpoint of heat resistance, the aromatic dicarboxylic acid is 50 mol% or more of the dicarboxylic acid component, preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, and particularly preferably 90 mol%. It may be 100% by mole or more. Dicarboxylic acids other than aromatic dicarboxylic acids include aliphatic dicarboxylic acids such as adipic acid, sebacic acid, succinic acid, glutaric acid and dimer acid, hexahydroterephthalic acid, hexahydroisophthalic acid, and 1,2-cyclohexanedicarboxylic acid. Examples thereof include alicyclic dicarboxylic acids such as acid, 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. In addition, polyoxycarboxylic acids such as p-oxybenzoic acid and oxycaproic acid, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, biphenylsulfonetetracarboxylic acid, and biphenyltetracarboxylic acid, and anhydrides thereof. You may use together.

  Further, 4,4′-biphenyldimethanol used as the glycol component of the polyester resin (A) needs to be contained in an amount of 15 mol% or more of the total glycol component, and preferably 50,4,4′-biphenyldimethanol. The mol% or more, more preferably 60 mol% or more, still more preferably 65 mol% or more, and most preferably 70 mol% or more. 4,4'-biphenyldimethanol is added to improve moldability, solder heat resistance, and light resistance. If the ratio is less than the above values, these characteristics tend to be lowered. Examples of glycol components other than 4,4′-biphenyldimethanol 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 the above glycols, ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neopentyl glycol, and 1,4-butanediol are selected from the viewpoint of heat resistance, polymerizability, moldability, cost, and the like. One or a mixture of two or more thereof is preferred. More preferably, it is one or a mixture of two or more 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 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 polyester resin, although it depends on production conditions. Moreover, you may use together polyhydric polyols, such as a trimethylol ethane, a trimethylol propane, glycerol, and a pentaerythritol.

  The polyester resin is preferably 160 mol% or more, more preferably 180 mol% or more, still more preferably 190 mol in terms of the total of the above dicarboxylic acid component and glycol component when the total constituent components are 200 mol%. % Or more, and may be 200 mol%. However, in either case, the dicarboxylic acid component does not exceed 100 mol% and the glycol component does not exceed 100 mol%.

  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 is used within a range of 20 mol% or less of the total acid component or the total diol component Also good.

  Although it does not specifically limit as a catalyst used when manufacturing a polyester resin (A), It is preferable that at least 1 type of compound chosen from the compound of Ge, Ti, Sb, 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.

  Also, as stabilizers for resins, 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 It is preferable to use at least one phosphorus compound selected from the group consisting of a series compound.

  The acid value of the polyester 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 polyester resin (A) of the present invention has a melting point (Tm) in DSC measurement of 280 ° C. or higher, preferably 290 ° C. or higher, more preferably 300 ° C. or higher, particularly preferably 310 ° C. or higher, and most preferably 320 ° C. or higher. It is. On the other hand, the upper limit of the melting point (Tm) of the polyester resin of the present invention is preferably 340 ° C. or lower. When Tm exceeds 340 ° C., the processing temperature required for injection molding the composition using the polyester resin (A) of the present invention becomes extremely high, so that the polyester resin decomposes during processing, and the desired physical properties and The appearance may not be obtained. 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, in the polyester resin (A) of the present invention, the difference between the melting point (Tm) and the temperature-falling crystallization temperature (Tc2) in DSC measurement is preferably 42 ° C. or less, more preferably 40 ° C. or less, more preferably 35 ° C. or lower, most preferably 30 ° C. or lower. The temperature-falling crystallization temperature (Tc2) is a temperature at which crystallization starts when the temperature is lowered from a temperature higher by 10 ° C. or more than the melting point in DSC measurement. The melting point (Tm) and the cooling crystallization temperature (Tc2) are measured by the methods described in the Examples section. When the difference between the melting point (Tm) and the cooling crystallization temperature (Tc2) is not more than the above temperature, crystallization proceeds easily, and dimensional stability and physical properties can be sufficiently exhibited. On the other hand, when the difference between the melting point (Tm) and the temperature rising crystallization temperature (Tc2) exceeds the above temperature, the LED reflector is molded in a short cycle of injection molding, so that the crystallization may not proceed sufficiently. Insufficient molding, etc., or crystallization has not been completed sufficiently, causing deformation and crystal shrinkage during heating in the subsequent process, causing problems of peeling from the sealing material and lead frame, resulting in increased reliability Lack.

  The intrinsic viscosity (IV) of the polyester resin (A) is preferably 0.10 to 0.70 dl / g, more preferably 0.20 to 0.65 dl / g, and still more preferably 0.25 to 0.00. 60 dl / g.

  The polyester resin (A) is preferably present in a proportion of 25 to 90% by mass, more preferably 40 to 75% by mass in the polyester resin composition of the present invention. When the ratio of the polyester resin (A) is less than the above lower limit, the mechanical strength becomes low. It becomes difficult to obtain.

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 size of the 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 with different particle sizes. Titanium may be used in combination. As a titanium oxide component density | concentration, it is 90 mass% or more, Preferably it is 95 mass% or more, More preferably, it is 97 mass% 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 ratio 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 polyester 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 the glass fiber, 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 preferably 20 μm or less, more preferably 15 μm or less, and even 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-sectional glass fibers include those that are substantially oval, substantially oval, and 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. Moreover, the glass fiber becomes a fiber bundle, and the thing of the chopped strand shape cut | disconnected by about 1-20 mm of fiber length can use it preferably. Furthermore, in order to increase the surface reflectance of the polyester resin composition, it is preferable that the difference in refractive index from the polyester resin is large, so use a glass composition that has a higher refractive index by changing the surface composition or by surface treatment. Is preferred.

  The ratio 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 polyester 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 acid, aluminum borate, sulfur 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 optimal amount, but it is possible to add a maximum of 50 parts by mass with respect to 100 parts by mass of the polyester resin (A), but from the viewpoint of the mechanical strength of the resin composition Therefore, 0.1 to 20 parts by mass is preferable, and 1 to 10 parts by mass is more preferable. When using talc, 0.1-5 mass parts is preferable with respect to 100 mass parts of polyester resins (A), More preferably, it is 0.5-3 mass parts. In order to improve the affinity with the polyester resin, the fibrous reinforcing material and the filler are preferably used after being treated with an organic treatment or a coupling agent, or used in combination with a coupling agent at the time of melt compounding. As the ring 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.

  Various additives of the conventional polyester resin composition for LED reflectors can be used for the polyester resin composition of the present invention. 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. .

  Resin composition stabilizers include organic antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, heat stabilizers, hindered amines, benzophenones, imidazoles, etc. Examples thereof include a light stabilizer, an ultraviolet absorber, a metal deactivator, and a copper compound. 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 an optimal quantity, it is possible to add a maximum of 5 mass parts with respect to 100 mass parts of polyester resins (A).

  A thermoplastic resin different from the 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 polyester resin composition of the present invention. The 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 polyester resin (A).

  As the impact modifier, 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 -Polytetramethylene glycol, polycaprolactone, or poly (polyethylene glycol) as a hard segment made of vinyl polymer resin such as styrene copolymer (SIS), acrylate copolymer, polybutylene terephthalate or polybutylene naphthalate. Polyester block copolymer in which the ball 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 impact modifier may be added in 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 polyester resin (A).

  When adding a thermoplastic resin other than the polyester resin (A) and an impact resistance improving material to the polyester resin composition of the present invention, it is preferable that a reactive group capable of reacting with the polyester is copolymerized, 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 aid is a combination of antimony trioxide, sodium antimonate, or 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. Although the addition amount of a flame retardant should just select an optimal quantity, it is possible to add a maximum of 50 mass parts with respect to 100 mass parts of polyamide resins (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. Although the addition amount of a mold release agent should just select an optimal quantity, it is possible to add a maximum of 5 mass parts with respect to 100 mass parts of polyester resins (A).

  Since the polyester resin composition of the present invention contains the polyester resin (A) as described above, the melting peak temperature (Tm) is preferably 280 ° C. or higher in DSC measurement, more preferably 290 ° C. or higher. More preferably, it is 300 ° C. or higher, particularly preferably 310 ° C. or higher, and most preferably 320 ° C. or higher. On the other hand, the upper limit of Tm of the polyester resin composition of the present invention is preferably 340 ° C. or lower.

  Furthermore, since the polyester resin composition of the present invention contains the polyester resin (A) as described above, the difference between the melting peak temperature (Tm) and the cooling crystallization temperature (Tc2) is 42 ° C. or less in DSC measurement. Preferably, it is 40 ° C. or lower, more preferably 35 ° C. or lower, still more preferably 30 ° C. or lower.

  The polyester resin (A) has an excellent balance between 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 the polyester resin (A) has a high melting point of 280 ° C. or higher and low water absorption, in addition to a thin wall, High cycle molding is possible.

  The polyester resin composition of this invention can be manufactured by mix | blending each above-mentioned component by a conventionally well-known method. For example, each component is added during the polycondensation reaction of the polyester resin (A), the polyester resin (A) and other components are dry blended, or each component is added using a twin screw type extruder. The method of melt-kneading can be mentioned.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but 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 polyester resin (IV)
It calculated | required from the solution viscosity at 30 degreeC in a 1,1,2,2-tetrachloroethane / phenol (2: 3 weight ratio) mixed solvent.
(2) Acid value The polyester resin (0.1 g) was dissolved by heating in 10 ml of benzyl alcohol, and then titrated with a 0.1N NaOH methanol / benzyl alcohol (1/9 volume ratio) solution.
(3) Melting point (Tm) of polyester resin, melting peak temperature (Tm) of resin composition, temperature drop crystallization temperature (Tc2)
Measurements were made with a differential thermal analyzer (DSC), RDC-220, manufactured by Seiko Electronics Corporation. 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. In addition, when not melting | dissolving at 330 degreeC, after hold | maintaining at 340 degreeC for 3 minutes, 340 to 130 degreeC was temperature-fallen at 10 degree-C / min. The peak temperature of the melting peak observed when the temperature was raised was defined as the melting point (Tm), and the peak temperature of the crystallization peak observed when the temperature was decreased was defined as the cooling crystallization temperature (Tc2).

(4) Moldability and dimensional stability 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 125 ° C., the film gate has a length of 100 mm, a width of 100 mm, Injection molding was performed using a flat plate mold having a thickness of 1 mmt. Molding was performed at an injection speed of 50 mm / second, a holding pressure of 30 MPa, an injection time of 10 seconds, and a cooling time of 10 seconds. The moldability was evaluated according to the following criteria.
○: 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.
Furthermore, in order to evaluate the dimensional stability of the obtained molded product, the molded product was heated at 180 ° C. for 1 hour. The dimension in the direction perpendicular to the flow direction before and after heating was measured, and the amount of dimensional change was determined as follows.
Dimensional change (%) = {dimension before heating (mm) −dimension after heating (mm)} / dimension before heating (mm) × 100
The dimensional stability was evaluated according to the following criteria.
○: Dimensional change is less than 0.2% ×: Dimensional change is 0.2% or more

(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 test piece was heated in an air reflow furnace (AIS-20-82C manufactured by ATEC) over 60 seconds from room temperature to 150 ° C, 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 surface swelling and deformation did not occur was defined as the reflow heat resistant temperature, and the solder heat resistance was evaluated according to the following criteria.
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 having a length of 100 mm, a width of 100 mm, and a thickness of 2 mm 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 having a length of 100 mm, a width of 100 mm, and a thickness of 1 mm 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 time of saturated water absorption−weight at time of drying) / weight at time of drying} × 100

(8) Fluidity Using Toshiba Machine's injection molding machine IS-100, the cylinder temperature is set to 330 ° C, the mold temperature is set to 120 ° C, the injection pressure set value is 40%, the injection speed set value is 40%, the metering 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) Silicone adhesion 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 having a length of 100 mm, a width of 100 mm, and a thickness of 2 mm is injection molded. Then, a test piece for evaluation was produced. On one side of this test piece, a silicone sealing material (manufactured by Shin-Etsu Silicone Co., ASP-1110, sealing material hardness D60) is coated 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, a cross-cut test (1 mm width crosscut 100 mass) based on JIS K5400 was performed on the sealing material film on the test piece, and the adhesion was evaluated according to the following criteria.
○: 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 having a length of 100 mm, a width of 100 mm, and a thickness of 2 mm is injection molded. A test piece for evaluation was prepared. About this test piece, UV irradiation was implemented by the illumination intensity of 50 mW / cm < ² > in the environment of 63 degreeC 50% RH using the super acceleration | stimulation weathering tester "eye 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 light resistance was evaluated according to the following criteria based on the retention of the light reflectance of the test piece after irradiation with respect to the light reflectance of the test piece before irradiation.
◎: Retention rate 95% or more ○: Retention rate less than 95% to 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 having a length of 100 mm, a width of 100 mm, and a thickness of 2 mm is injection molded. Then, a test piece for evaluation was produced. Using this test piece, it processed at 150 degreeC with a hot air dryer for 2 hours, confirmed yellowing visually, and evaluated it on the following references | standards.
○: No change △: Slightly yellow ×: Yellowish

Example 1
A 20 liter stainless steel autoclave with a stirrer was charged with 3880 g of high-purity dimethyl terephthalic acid, 2782 g of 4,4′-biphenyldimethanol, 1922 g of ethylene glycol, 2 g of manganese acetate, and 0.86 g of germanium dioxide. While raising the temperature to 300 ° C., the pressure of the reaction system was gradually decreased 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 polyester was 0.60 dl / g, and the resin composition was 100 mol% terephthalic acid, 65.0 mol% 4,4′-biphenyldimethanol, ethylene glycol as determined by ¹ H-NMR measurement. Was 34.5 mol% and diethylene glycol was 0.5 mol%. The composition and characteristic values of the obtained polyester resin are shown in Table 1.

(Examples 2 to 4)
Each polyester resin was obtained in the same manner as in the polymerization of the polyester resin of Example 1 except that the amount and type of raw materials used were changed. Table 1 shows the composition and characteristic values of the obtained polyester resins. Diethylene glycol is a by-product of condensation of ethylene glycol.

(Example 5)
A 20-liter stainless steel autoclave with a stirrer was charged with 3880 g of high-purity dimethyl terephthalic acid, 2782 g of 4,4′-biphenyldimethanol, 1922 g of ethylene glycol, 2 g of manganese acetate, and 0.86 g of germanium dioxide. After transesterification, high-purity terephthalic acid Was added, and the temperature of the reaction system was gradually decreased to 13.3 Pa (0.1 Torr) while raising the temperature to 300 ° C. over 60 minutes, and further polycondensation reaction was performed at 310 ° C. and 13.3 Pa. did. 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 polyester was 0.60 dl / g, and the resin composition was 100 mol% terephthalic acid, 65.0 mol% 4,4′-biphenyldimethanol, ethylene glycol as determined by ¹ H-NMR measurement. Was 34.5 mol% and diethylene glycol was 0.5 mol%. The composition and characteristic values of the obtained polyester resin are shown in Table 1.

(Comparative 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 polyester had an IV of 0.61 dl / g and a resin composition of 100 mol% terephthalic acid, 98.0 mol% ethylene glycol, and 2.0 mol% diethylene glycol, as determined by ¹ H-NMR. It was. The composition and characteristic values of the obtained polyester resin are shown in Table 2.

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

(Comparative 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 resin obtained by solid-phase polymerization at 230 ° C. and 0.1 mmHg for 10 hours, having a melting point of 310 ° C., an intrinsic viscosity [η] of 1.33 dl / g, and a terminal sealing rate of 90%. Got. The composition and characteristic values of the obtained polyamide resin are shown in Table 2.

(Examples 6 to 13, Comparative Examples 6 to 10)
Using the components and mass ratios described in Tables 3 and 4, using a twin screw extruder STS-35 manufactured by Coperion Co., Ltd., melt-kneading at the melting point of the polyester resin (A) or polyamide resin + 15 ° C., Examples 6 to 13 and the resin composition of Comparative Examples 6-10 were obtained. In Tables 3 and 4, the details of the materials used other than the polyester resin (A) are as follows.
Titanium oxide (B): manufactured by Ishihara Sangyo Co., Ltd., Taipei CR-60, rutile TiO ₂ , average particle size 0.2 μm
Reinforcing material (C): Glass fiber (manufactured by Nitto Boseki 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] (Chiba Specialty Chemicals, Irganox 1010)

  The resin compositions obtained in Examples 6 to 13 and Comparative Examples 6 to 10 were used for evaluation of various properties. The evaluation results are also shown in Tables 3 and 4.

  From Table 1 and Table 3, in the resin composition (Examples 6-13) using the polyester resin (Examples 1-5) which satisfy | fills the requirements of this invention, the melting peak temperature by DSC of a polyester resin composition is 280 degreeC. In the above case, it can be applied to the reflow soldering process. Further, when the melting peak temperature exceeds 310 ° C, the reflow heat resistance temperature is 280 ° C or higher, so it can be applied to the gold / tin eutectic soldering process. In addition to exhibiting solder heat resistance, it has excellent adhesion to the encapsulant, which is an important characteristic for LED applications, and surface reflectance. Furthermore, it has moldability, fluidity, dimensional stability, low water absorption, light resistance, and heat resistance. A special effect of being excellent in denaturation was confirmed. On the other hand, from Tables 2 and 4, the resin composition (Comparative Examples 6 to 9) using the polyester resin (Comparative Examples 1 to 4) that does not satisfy the requirements of the present invention can satisfy all these characteristics. There wasn't. Although the polyamide resin of Comparative Example 5 has a high melting point, the resin composition (Comparative Example 10) using the polyamide resin of Comparative Example 5 has a reflow heat resistance temperature of 280 ° C. or higher because of water absorption due to the amide structure. It was not satisfactory, and it was inferior to light resistance and heat yellowing.

  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 polyester resin is used, it can be suitably used for a reflector for a surface-mounted LED while highly satisfying necessary characteristics.

Claims (10)

A dicarboxylic acid component containing at least 80 mol% of at least one selected from the group consisting of 4,4′-biphenyldicarboxylic acid, terephthalic acid, and 2,6-naphthalenedicarboxylic acid; and 4,4′-biphenyldimethanol A polyester resin comprising a glycol component containing 15 mol% or more, wherein glycol components other than 4,4′-biphenyldimethanol are ethylene glycol, 1,4-cyclohexanedimethanol, 1,3-propanediol, neo It is at least one selected from the group consisting of pentyl glycol and 1,4-butanediol (however, when the glycol component contains ethylene glycol, it may contain 1 to 5 mol% of diethylene glycol with respect to the amount of ethylene glycol). ), Melting point is 280 ° C or higher Polyester resin to be collected. Contains at least 15 mol% of a dicarboxylic acid component that is at least one selected from the group consisting of 4,4′-biphenyldicarboxylic acid, terephthalic acid, and 2,6-naphthalenedicarboxylic acid, and 4,4′-biphenyldimethanol And a glycol component other than 4,4′-biphenyldimethanol is ethylene glycol (however, it may contain 1 to 5 mol% of diethylene glycol with respect to the amount of ethylene glycol). The polyester resin according to claim 1, wherein the polyester resin has a melting point of 280 ° C. or higher. The polyester resin according to claim 1 or 2 , wherein the difference between the melting point (Tm) of the polyester resin and the cooling crystallization temperature (Tc2) is 42 ° C or less. The polyester resin according to any one of claims 1 to 3 , wherein the acid value of the polyester resin is 1 to 40 eq / t. The polyester resin (A) according to any one of claims 1 to 4 , titanium oxide (B), at least one reinforcing material (C) selected from the group consisting of a fibrous reinforcing material and a needle-shaped reinforcing material, and Contains non-fibrous or non-needle filler (D), and 100 parts by mass of polyester resin (A), titanium oxide (B), reinforcing material (C), and non-fibrous or non-needle filler ( D) is present in a ratio of 0.5 to 100 parts by mass, 0 to 100 parts by mass, and 0 to 50 parts by mass, respectively, and a polyester resin composition for use in a reflector for a surface mount LED . Non-fibrous or non-acicular filler (D) is talc, in claim 5, characterized in that it contains a proportion of talc, from 0.1 to 5 parts by weight relative to the polyester resin (A) 100 parts by mass of The polyester resin composition as described. Solder reflow heat-resistant temperature is 260 degreeC or more, The polyester resin composition of Claim 5 or 6 characterized by the above-mentioned. The polyester resin composition according to any one of claims 5-7 in which the solder reflow heat-resistant temperature is characterized in that at 280 ° C. or higher. Melting peak temperature of the polyester resin composition (Tm) is not less 280 ° C. or higher, the difference between the melting peak temperature (Tm) and crystallization temperature (Tc2) is, according to claim 5-6, characterized in that at 42 ° C. or less The polyester resin composition according to any one of 8 . A surface mount LED reflector, which is obtained by molding using the polyester resin composition according to any one of claims 5 to 9 .