JP2014159536A - Diallyl phthalate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for molding that is excellent in filling property, releasability and the like to a die, and is easily molded in a molding process, and in which a molded product is excellent in heat resistance, has a high degree of whiteness, and can keep a high degree of whiteness over a long period of time.SOLUTION: A diallyl phthalate resin composition contains a diallyl phthalate resin (a), a polymerization initiator (b), titanium oxide (c), and an antioxidant (d). The antioxidant (d) is a phosphorus-based antioxidant, and the content in the composition is 0.1-10 pts.wt. with respect to 100 pts.wt. of the diallyl phthalate resin (a). The diallyl phthalate resin composition is cured, and thereby a package housing a light-emitting diode therein can be molded which is excellent in heat resistance and light resistance, and can keep a high degree of whiteness over a long period of time.

Description

  The present invention relates to a diallyl phthalate resin composition that is excellent in heat resistance and gives a high whiteness and a molded product that can maintain the whiteness for a long period of time.

  In recent years, there has been a demand for a storage package using a material that has excellent heat resistance and can maintain high whiteness for a long time in a lighting fixture using a light emitting diode. For example, a ceramic material is used as the material of the storage package. Ceramic materials are widely used in lighting fixtures because of high surface reflection of visible light and excellent heat dissipation and electrical insulation. However, since ceramic materials are inferior in terms of mold filling properties, mold release properties, and the like in molding processing, alternative materials have been studied.

  Diallyl phthalate resin has excellent dimensional stability, heat resistance, and heat and humidity resistance, as well as excellent mold filling and releasability, etc., for molding and molding materials for electrical and electronic parts. Widely used as a resin.

  As an example in which diallyl phthalate resin is used for a storage package of a light emitting diode, Patent Document 1 contains diallyl phthalate resin, a polymerization initiator, titanium oxide, and a light stabilizer. A diallyl phthalate resin composition is described which is adjusted to 97% by weight and whose content is 5 to 120 parts by weight based on the total weight of the composition. However, since the component contained in the diallyl phthalate resin composition causes yellowing over time, it has been insufficient in terms of maintaining long-term whiteness.

  One method for solving the above problem includes a method of adding an antioxidant to the diallyl phthalate resin composition. As the antioxidant used in the thermosetting resin composition such as diallyl phthalate resin, a phenolic antioxidant is generally used. However, the phenolic antioxidant captures peroxy radicals generated in the process of auto-oxidation and is oxidized to quinone compounds via phenoxy radicals. This quinone compound is known to be a coloring substance, and in a resin composition requiring whiteness, a phenolic antioxidant cannot be used from the viewpoint of formation of a colored compound. Therefore, development of a resin composition that uses diallyl phthalate resin having excellent moldability as a package material, has excellent heat resistance, and can maintain high whiteness for a long period of time is required.

JP2008-255338

  The object of the present invention is to provide good mold filling and releasability, etc. in molding, easy to mold, molded products have excellent heat resistance, high whiteness, and high whiteness over a long period of time. It is to provide a maintainable diallyl phthalate resin composition.

As a result of intensive studies to solve the above problems, the present inventor has found that a diallyl phthalate resin composition containing a specific antioxidant can solve the above problems. That is, the present invention contains a diallyl phthalate resin (a), a polymerization initiator (b), titanium oxide (c), and an antioxidant (d), and the antioxidant (d) is a phosphorus-based antioxidant. A diallyl phthalate resin composition characterized in that the content of the antioxidant (d) in the resin composition is 0.1 to 10 parts by weight with respect to 100 parts by weight of the diallyl phthalate resin (a). The present invention was completed by finding out that it has excellent heat resistance and can maintain high whiteness for a long time.
This invention is completed based on the said knowledge, and provides a diallyl phthalate resin composition below.

Item 1. Containing diallyl phthalate resin (a), polymerization initiator (b), titanium oxide (c), and antioxidant (d),
The diallyl, wherein the antioxidant (d) is a phosphorus antioxidant and the content in the composition is 0.1 to 10 parts by weight with respect to 100 parts by weight of the diallyl phthalate resin (a). Phthalate resin composition.
Item 2. Item 2. The phosphorous antioxidant is one or more selected from the group consisting of a phosphorous acid antioxidant, a hypophosphorous acid antioxidant, and a phosphoric acid antioxidant. Diallyl phthalate resin composition.
Item 3. Item 3. The diallyl phthalate resin composition according to item 1 or 2, wherein the titanium oxide (c) is a rutile type and is subjected to a surface treatment.
Item 4. The hardened | cured material obtained by thermosetting the diallyl phthalate resin composition in any one of claim | item 1-3.
Item 5. Item 4. A reflector for LED obtained by molding the diallyl phthalate resin composition according to any one of Items 1 to 3.
Item 6. Item 6. An LED lighting apparatus comprising the LED reflector according to Item 5.

Since the diallyl phthalate resin composition of the present invention is excellent in heat resistance, the cured product obtained by thermosetting has high whiteness, and it is possible to maintain high whiteness for a long period of time. Therefore, it can be suitably used as a molding material in the electric / electronic field where high heat resistance and whiteness are required.
For example, the diallyl phthalate resin composition of the present invention is easy to mold, has a high whiteness on the surface of the molded product, and can improve the irradiation efficiency and reflection efficiency of light emission from the LED chip. A resin package for housing the light emitting element can be provided.

Hereinafter, the present invention will be described in detail.
Diallyl phthalate resin composition The present invention comprises a diallyl phthalate resin (a), a polymerization initiator (b), titanium oxide (c), and an antioxidant (d), and the antioxidant (d) is a phosphorus-based oxidation. A diallyl phthalate resin composition, which is an inhibitor and has an antioxidant (d) content of 0.1 to 10 parts per 100 parts by weight of diallyl phthalate resin (a) in the resin composition It is.

Diallyl phthalate resin (a)
The diallyl phthalate resin (a) used in the present invention is typified by diallyl phthalate resins such as diallyl orthophthalate prepolymer, diallyl isophthalate prepolymer, diallyl terephthalate prepolymer, and the like alone or in a mixture of two or more. It may be. When high heat resistance is required for the molded product, it is preferable to use an isotype or paratype. The resin may be a prepolymer made of a copolymer of two or more so-called diallyl phthalate monomers such as diallyl orthophthalate monomer, diallyl isophthalate monomer, diallyl terephthalate monomer. In this case, hydrogen atoms on the benzene ring may be substituted with halogen atoms such as chlorine and bromine, and prepolymers in which all or part of the unsaturated bonds present in the molecule are hydrogenated are also shown here. Shall be included.

The diallyl phthalate resin (a) may contain a diallyl phthalate monomer. Examples of the diallyl phthalate monomer include diallyl orthophthalate monomer, diallyl isophthalate monomer, diallyl terephthalate monomer, and the like.
The content of the diallyl phthalate monomer is preferably 0.01 to 5% by weight, more preferably 0.1 to 2% by weight, and still more preferably 0.2 to 1.9% by weight with respect to the entire resin composition.

  The diallyl phthalate resin (a) is preferably 20,000-60,000 in terms of weight average molecular weight (measured by GPC, converted to standard polystyrene), and iodine value is 50-90 in consideration of the viscosity of the resin. It is preferable that the softening point is 65 to 110 ° C.

  The content of the diallyl phthalate resin (a) is preferably 10 to 70% by weight, more preferably 30 to 50% by weight, based on the entire resin composition.

Polymerization initiator (b)
As a polymerization initiator (b) used by this invention, if the said diallyl phthalate resin is thermosetted, it can be especially used without a restriction | limiting. Specifically, dicumyl peroxide, tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoyl) Peroxy) hexane, 1,1-di (tert-hexylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (tert-butylperoxy) valerate, tert-butylperoxy Examples thereof include carbonate, tert-butyl peroxypivalate, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl monocarbonate, tert-butyl peroxy-2-ethylhexyl monocarbonate, and the like. Of these, tert-butylperoxy-2-ethylhexyl monocarbonate is preferred.

  The content of the polymerization initiator (b) in the resin composition is 0.1 to 5 parts by weight, preferably 1 to 4 parts by weight with respect to 100 parts by weight of the diallyl phthalate resin from the viewpoint of moldability. is there.

Titanium oxide (c)
As titanium oxide (c) used in the present invention, there are three crystal types of a rutile type, an anatase type and a brookite type, which may be any, but preferably a rutile type. The average particle diameter of titanium oxide (c) may be in the range of 0.01 to 1 μm, and preferably in the range of 0.1 to 0.5 μm. The average particle diameter can be measured by a laser diffraction scattering method or the like.
By setting the average particle diameter of titanium oxide (c) within the above range, a diallyl phthalate resin composition that gives a molded article having high whiteness and high surface reflectance can be obtained.
Further, as the titanium oxide (c), those subjected to surface treatment are preferable, and examples of the surface treatment agent include metal oxides such as silica, alumina and zirconia; silane coupling agents, titanium coupling agents, organic acids, Examples include organic substances such as polyol and silicone. Titanium oxide surface-treated with at least one selected from silica, alumina, zirconia and organic substances is preferable. Of these, titanium oxide surface-treated with silica and alumina is preferred from the viewpoint of heat resistance.

The following commercially available products are known as such titanium oxide (c), and any of these can be used in the present invention.
R-11P, TCR-52, D-918, FTR-700 (all trade names) manufactured by Sakai Chemical Industry, which is a rutile type titanium oxide, Type CR CR-50 manufactured by Ishihara Sangyo Co., Ltd.,
CR-50-2, CR-60, CR-60-2, CR-63, CR-80, CR-90, CR-90-2, CR-93, CR-95, CR-97, R-820, R-830, R-930, R-980, R-680, R-550, PF-739, PC-3, UT-771 (all trade names), JR-403 manufactured by Teika Co., Ltd., JR- 405, JR-805, JR-806, JR-701, JR-800, etc. (all trade names), Fuji-Titanium Industry Co., Ltd. TR-600, TR-700, TR-750, TR-840, TR -900 (both are trade names).
Moreover, content of titanium oxide (c) in a resin composition is 5-300 weight part with respect to 100 weight part of diallyl phthalate resin (a), Preferably it is 100-230 weight part.
If it is less than 5 parts by weight, it is insufficient in terms of whiteness, heat resistance and light resistance, and if it exceeds 300 parts by weight, it is inferior in moldability.

  Examples of the antioxidant (d) used in the present invention include phosphorous acid-based, hypophosphorous acid-based and phosphoric acid-based antioxidants.

  Phosphite antioxidants include bis (nonylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphos Phyto, 2,2'-methylenebis (4,6-di-t-butylphenyl) octyl phosphite, triethyl phosphite, tri-n-butyl phosphite, triphenyl phosphite, diphenyl monooctyl phosphite, tri (p -Cresyl) phosphite, diphenyl monodecyl phosphite, diphenyl mono (tridecyl) phosphite, tris (2-ethylhexyl) phosphite, phenyl didecyl phosphite, tridecyl phosphite, tetraphenyl dipropylene glycol diphosphine Bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, tris (tridecyl) phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis [2,4-di (1-phenyl) Isopropyl) phenyl] pentaerythritol diphosphite, trilauryl trithiophosphite, trioleyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, tris (nonylphenyl) phosphite, distearyl pentaerythritol diphosphite Phosphite, tris (mono, dinonylphenyl) phosphite, tristearyl phosphite, 4,4'-butylidenebis (3-methyl-6-tert-butylphenylditridecyl) phosphite, tetra (C12-C15 mixed alkyl) -4 4'-isopropylidene diphenyl diphosphite, tetra (tridecyl) -4,4'-butylidenebis (3-methyl-6-tert-butylphenol) diphosphite, hexa (tridecyl) -1,1,3-tris (2-methyl) -5-t-butyl-4-hydroxyphenyl) butane-triphosphite, hydrogenated bisphenol A phosphite polymer, 2-[[2,4,8,10-tetrakis (1,1-dimethylether) dibenzo [d, f] [1,3,2] dioxaphosphin 6-yl] oxy] -N, N-bis [2-[[2,4,8,10-tetrakis (1,1 dimethylethyl) dibenzo [d , F] [1,3,2] dioxaphosphin-6-yl] oxy] -ethyl] ethanamine, 2,2'-methylenebis (4,6-di-t-butyl) And the like can be exemplified phenyl) octyl phosphite.

  As hypophosphite antioxidants, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2,5-dihydroxyphenyl) -10H-9-oxa-phospha Phenanthrene-10-oxide, tetrakis (2,4-di-t-butylphenyloxy) 4,4'-biphenylene-di-phosphine, tetrakis (2,4-di-t-butyl-5-methylphenyloxy) 4 4,4'-biphenylene-di-phosphine, tetrakis (2,4-di-t-butyl-5-ethylphenyloxy) 4,4'-biphenylene-di-phosphine, tetrakis (2,4-di-t-butyl) -5-butylphenyloxy) 4,4'-biphenylene-di-phosphine, tetrakis (2,4-di-t-butyl-5-hexylphenyl) Carboxymethyl) 4,4'-biphenylene - di - can be exemplified phosphine.

Examples of phosphoric acid antioxidants include 2,2′-methylenebis (4,6-di-tert-butylphenyl) phosphate, 2,4,8,10-tetra-tert-butyl-6-hydroxy-12H— An example is dibenzo [d, g] [1,3,2] dioxaphosphocin-6-one.
Of these, phosphorous acid antioxidants are preferable in terms of heat resistance and light resistance.

  Content of antioxidant (d) in a resin composition is 0.1-10 weight part with respect to 100 weight part of diallyl phthalate resin (a), Preferably it is 0.2-7 weight part, More Preferably it is 0.5-5 weight part.

  In addition to the above components, the diallyl phthalate resin composition of the present invention does not reduce the whiteness of the molded product of the resin composition of the present invention and does not affect other physical properties (heat resistance, light resistance, etc.). As long as it can contain additives such as ultraviolet absorbers, light stabilizers, internal mold release agents, sulfur-based antioxidants, fillers, plasticizers, crystal nucleating agents and the like.

The manufacturing method of the diallyl phthalate resin composition of the present invention is not particularly limited as long as it can be prepared by uniformly mixing predetermined amounts of each of the above components.
The curing and molding methods of the prepared resin composition are not particularly limited. A desired molded product can be obtained by various molding methods such as normal injection molding, transfer molding, compression molding, lamination molding, and extrusion molding.
The diallyl phthalate resin composition of the present invention can be used as a raw material for a molded product that is particularly required to maintain whiteness and the whiteness for a long period of time, such as an LED chip storage package.

In this invention, whiteness means the whiteness of the surface of the hardened | cured material which shape | molded and hardened the diallyl phthalate resin composition of this invention on the following conditions.
That is, a molded product obtained by molding at a temperature and time at which the diallyl phthalate resin composition is cured, specifically, for example, by compression molding at 160 ° C. higher than the softening point of the resin composition for 3 minutes, A molded product having a thickness of 3 mm and a diameter of 100 mm was obtained, and by using this molded product, a colorimetry color difference meter ZE6000 (manufactured by Nippon Denshoku Industries Co., Ltd.) was used, and brightness by Hunter's color difference formula defined in JIS Z8730 ( L value), redness (a value), and yellowness (b value) were obtained, and whiteness was obtained from these values according to the following formula (1).
Whiteness = 100 − [(100−L) ² + a ² + b ² ] ^1/2 (1)
[In the formula, L represents lightness, a and b represent chromaticity (a is in the red direction, -a is in the green direction, b is in the yellow direction, and -b is in the blue direction). ]
The diallyl phthalate resin composition of the present invention has an initial whiteness of 94 or more determined by the above formula (1) of a cured product obtained under the above molding conditions. If it is 94 or more, the extraction efficiency of light emission from the LED chip can be sufficiently obtained.

The diallyl phthalate resin composition of the present invention is excellent in high whiteness, heat resistance, and light resistance, and can be molded into a molded product having electrical characteristics because it can maintain the whiteness for a long period. Can be used.
As an LED chip storage package, for example, as shown in FIG. 1 or 2 of Japanese Patent Laid-Open No. 2003-163378, a recess is formed on the bottom surface of the package that opens upward, and the LED chip is stored in the recess. It becomes a shape that can be made. In recent years, storage packages of various materials and shapes have been devised. The diallyl phthalate resin composition of the present invention can be applied to the molding of these storage packages, and various light-emitting devices that store LED chips can be created by these storage packages.
The hollow package can be molded by applying a mold release agent on the inner surface of the mold, pouring the composition of the present invention into the mold, and heating and curing to obtain a molded product. Since the composition of the present invention is excellent in fluidity, the composition can be poured into the details of the mold, so that even a mold having a small and intricate structure can be molded with excellent finish. Can be obtained.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. The present invention is not particularly limited by these. In addition, the physical property of the shaping | molding board obtained by the Example and the comparative example was tested and evaluated by the following test method.

1) Whiteness initial value (W ₀ )
The molded product is cooled to room temperature, and by using a colorimetric color difference meter ZE6000 (manufactured by Nippon Denshoku Industries Co., Ltd.), brightness (L value), redness (a value) according to Hunter color difference formula defined in JIS Z8730, and The degree of yellowness (b value) is obtained, and the degree of whiteness obtained from these numerical values by the following equation.
Whiteness = 100 − [(100−L) ² + a ² + b ² ] ^1/2

2) Heat discoloration resistance _{(H 1} and _H 2)
The molded product was treated for 6 hours and 12 hours with a hot air circulating dryer maintained at 180 ° C., and the whiteness (W ₁ ) and (W ₂ ) were determined in the same manner as described above. It was calculated whiteness retention for whiteness initial value W ₀ of the (percent) by the following equation.
H ₁ (%) = (W ₁ / W ₀ ) × 100
H ₂ (%) = (W ₂ / W ₀ ) × 100
W ₁ : Whiteness of molded plate treated at 180 ° C. for 6 hours W ₂ : Whiteness of molded plate treated at 180 ° C. for 12 hours H ₁ : Whiteness retention (%) of molded plate treated at 180 ° C. for 6 hours
H ₂ : Whiteness retention rate (%) of molded plate treated at 180 ° C. for 12 hours

3) Releasability When the molded product was molded, the release state of the molded product main body and the burr was observed, and the release property was visually evaluated. The evaluation criteria are shown below.
○: Good releasability.
X: The mold release property of the molded product main body or the burr part is poor or the curing is poor.

Example 1
Diallyl isophthalate resin [trade name: Daiso Isodap, weight average molecular weight 30000 to 50,000, manufactured by Daiso Corporation] 100 parts by weight, titanium oxide [trade name: R-820: surface treated with silicon, alumina and zinc oxide , Titanium dioxide content, 93%; manufactured by Ishihara Sangyo Co., Ltd.] 150 parts by weight, polymerization initiator [trade name: Perbutyl E, purity 97% or more, manufactured by NOF Corporation] 3.75 parts by weight, And 1.25 parts by weight of a phosphorus antioxidant (trade name: PEP36, manufactured by ADEKA Corporation) and 1.25 parts by weight of a mold release agent (compound name: zinc stearate, manufactured by Sakai Chemical Industry Co., Ltd.) By mixing, diallyl phthalate resin composition 1 was obtained. Table 1 summarizes the compositions. The obtained resin composition 1 was compression molded at 160 ° C. higher than the melting point for 3 minutes to obtain a molded plate 1 having a thickness of 3 mm and a diameter of 100 mm. The obtained molded plate 1 was used and evaluated by the above measuring method. The evaluation results are shown in Table 2.

Example 2
Diallyl phthalate resin composition 2 was obtained under the same conditions as in Example 1 except that the content of the phosphorus-based antioxidant [trade name: PEP36, manufactured by ADEKA Corporation] was changed to 2.50 parts by weight. Table 1 summarizes the compositions. The obtained diallyl phthalate resin composition 2 was molded under the same conditions as in Example 1 to obtain a molded plate 2 and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Example 3
A diallyl phthalate resin composition 3 was obtained under the same conditions as in Example 1 except that the content of the phosphorus-based antioxidant [trade name: PEP36, manufactured by ADEKA Corporation] was changed to 3.75 parts by weight. Table 1 summarizes the compositions. The obtained diallyl phthalate resin composition 3 was molded under the same conditions as in Example 1 to obtain a molded plate 3 and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 1
Diallyl isophthalate resin [trade name: Daiso Isodap, weight average molecular weight 30000 to 50,000, manufactured by Daiso Corporation] 100 parts by weight, titanium oxide [trade name: R-820: surface treated with silicon, alumina and zinc oxide , Titanium dioxide content, 93%; manufactured by Ishihara Sangyo Co., Ltd.] 150 parts by weight, polymerization initiator [trade name: Perbutyl E, purity 97% or more, manufactured by NOF Corporation] 3.75 parts by weight, And 1.25 parts by weight of a release agent (compound name: zinc stearate, manufactured by Sakai Chemical Industry Co., Ltd.) were mixed to obtain diallyl phthalate resin composition 4. The obtained diallyl phthalate resin composition 4 was compression molded at 160 ° C. higher than the melting point for 3 minutes to obtain a molded plate 4 having a thickness of 3 mm and a diameter of 100 mm. Evaluation was performed in the same manner as in Example 1 using the obtained molded plate 4. The evaluation results are shown in Table 2.

Comparative Example 2
Diallyl isophthalate resin [trade name: Daiso Isodap, weight average molecular weight 30000 to 50,000, manufactured by Daiso Corporation] 100 parts by weight, titanium oxide [trade name: R-820: surface treated with silicon, alumina and zinc oxide , Titanium dioxide content, 93%; manufactured by Ishihara Sangyo Co., Ltd.] 150 parts by weight, polymerization initiator [trade name: Perbutyl E, purity 97% or more, manufactured by NOF Corporation] 3.75 parts by weight, 2.5 parts by weight of a phenolic antioxidant (trade name: Irganox 1076, manufactured by BASF) and 1.25 parts by weight of a mold release agent (compound name: zinc stearate, manufactured by Sakai Chemical Industry Co., Ltd.) are mixed and diallyl A phthalate resin composition 5 was obtained. The obtained diallyl phthalate resin composition 5 was compression molded at 160 ° C. higher than the melting point for 3 minutes to obtain a molded plate 5 having a thickness of 3 mm and a diameter of 100 mm. The obtained molded plate 5 was used and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 3
Resin composition 6 was obtained under the same conditions as in Comparative Example 2 except that the antioxidant was changed to 2.5 parts by weight of a phenolic antioxidant (trade name: Songnox 1010, manufactured by Songwon Industrial). The obtained resin composition 6 was molded under the same conditions as in Comparative Example 2 to obtain a molded plate 6 and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 4
Resin composition 7 was obtained under the same conditions as in Comparative Example 2, except that the antioxidant was changed to 2.5 parts by weight of a phenolic antioxidant (trade name: AO-80, manufactured by ADEKA Corporation). The obtained resin composition 7 was molded under the same conditions as in Comparative Example 2 to obtain a molded plate 7 and evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

In Table 1,
1. Diallyl phthalate resin ^{* 1)} : Daiso isopap (trade name): weight average molecular weight (polystyrene conversion) 3 to 5 × 10 ⁴ , manufactured by Daiso Corporation Titanium oxide powder ^{* 2)} : R-820 (trade name): rutile titanium oxide, titanium dioxide 93.0% or more, surface treatment agent; alumina, silica, zinc oxide, primary particle size 0.26 μm, Ishihara Sangyo Co., Ltd. 3. Polymerization initiator ^{* 3)} : Perbutyl E (trade name) t-butyl peroxy-2-ethylhexyl monocarbonate, manufactured by NOF Corporation. Antioxidant ^{* 4)} :
PEP-36 (trade name) Bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite: Phosphorous antioxidant, ADEKA Corporation Irganox 1076 (trade name): Phenol-based oxidation Antioxidant, manufactured by BASF Songnox 1010 (trade name): phenolic antioxidant, manufactured by Songwon Industrial AO-80 (trade name): phenolic antioxidant, manufactured by ADEKA Corporation Release agent ^{* 5)} : Zinc stearate, manufactured by Sakai Chemical Industry Co., Ltd.

  Compared with the molded plate 4 to which no phosphorus-based antioxidant is added (Comparative Example 1), the molded plates 1 to 3 (Examples 1 to 3), which are molded plates to which a phosphorus-based antioxidant is added, have initial whiteness. Although the value of is almost unchanged, it can be seen that the whiteness after the heat resistance test (180 ° C.) is high. From this, it can be seen that the phosphorus-based antioxidant reduces the degree of discoloration due to heat of the molded plate. On the other hand, molded plates 5 to 7 (Comparative Examples 2 to 4), which are molded plates to which a phenolic antioxidant that is usually used, are added, both of the initial whiteness and the whiteness after the heat resistance test, are phosphorus antioxidants. It is lower than the molded plates 1 to 3, which are molded plates to which is added. This is presumably because the phenolic antioxidant was oxidized by heat at the time of molding and heat of the heat resistance test and became a colored material. From the above, it can be seen that the initial whiteness can be maintained and the heat resistance can be improved by adding a phosphorus-based antioxidant.

The diallyl phthalate resin composition of the present invention is excellent in heat resistance, has a high whiteness, gives a molded product that can maintain the whiteness for a long time, and has excellent electrical characteristics. It is extremely useful, for example, it can form a package for housing a product, particularly a light emitting diode.

Claims (6)

Containing diallyl phthalate resin (a), polymerization initiator (b), titanium oxide (c), and antioxidant (d),
The diallyl, wherein the antioxidant (d) is a phosphorus antioxidant and the content in the composition is 0.1 to 10 parts by weight with respect to 100 parts by weight of the diallyl phthalate resin (a). Phthalate resin composition.   2. The phosphorus-based antioxidant is at least one selected from the group consisting of a phosphorous acid-based antioxidant, a hypophosphorous acid-based antioxidant, and a phosphoric acid-based antioxidant. Diallyl phthalate resin composition.   The diallyl phthalate resin composition according to claim 1 or 2, wherein the titanium oxide (c) is a rutile type and is subjected to a surface treatment.   Hardened | cured material obtained by thermosetting the diallyl phthalate resin composition in any one of Claims 1-3.   A reflector for LED, wherein the diallyl phthalate resin composition according to claim 1 is molded. The LED lighting fixture formed by mounting | wearing with the LED reflector of Claim 5.