JP2008050539A - Unsaturated polyester resin composition and molded article of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an unsaturated polyester resin composition having a high heat resistance without using an environmentally loading material and without increasing working processes. <P>SOLUTION: The unsaturated polyester resin composition comprises 20-30 pts.wt. of a mixture of an unsaturated polyester resin and a diallyl phthalate resin resin, 50-60 pts.wt. of an inorganic filler, 5-15 pts.wt. of glass fibers and 1-10 pts.wt. of a reactive silicone oil having organic acid groups based on acrylic acid at least introduced on both terminals. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an unsaturated polyester resin composition for sealing electronic parts such as capacitors, coils, resistors, etc., and electrical parts such as terminal blocks, coil bobbins and the like, and a molded product thereof.

Unsaturated polyester resin compositions are widely used as sealing materials for various electronic parts or as molding materials for electronic parts, and various types of unsaturated polyester resin compositions have been proposed so far (for example, patent documents). 1-3). The above electronic components are mounted by solder reflow, and the solder used for the reflow is becoming lead-free as part of recent environmental measures. When lead-free solder is used, it is necessary to increase the solder temperature from the conventional 220-230 ° C. to 250-260 ° C. by about 30 ° C. However, raising the solder temperature by about 30 ° C. increases the thermal stress on the various molding materials described above, and there are concerns about problems such as cracking during reflow. Further, when an environment in which an electronic component is exposed to a high temperature even for a short time is assumed, it is necessary to improve heat resistance and improve reliability as an electronic component.
JP 2005-68167 A JP-A-9-316338 Japanese Patent Laid-Open No. 9-87347

  Up to now, as a method for improving heat resistance, for example, it can be considered that it is limited to an inorganic filler having no hydrate, but the effect is not always sufficient, and flame resistance is required. It is conceivable to use halogen-based or phosphorus-based flame retardants for these, but these flame retardants are environmentally hazardous substances and their use is restricted. As another method, after-baking of the molded product is also conceivable, but a separate work process is required, leading to an increase in cost such as an increase in energy consumption. The effect was relatively low.

  From the background as described above, an object of the present invention is to provide an unsaturated polyester resin composition having high heat resistance without using environmentally hazardous substances and without increasing the number of work steps.

  In order to solve the above-mentioned problems, the present invention first includes 20 to 30 parts by weight of a mixture of unsaturated polyester resin and diallyl phthalate resin, 50 to 60 parts by weight of an inorganic filler, and 5 to 15 parts by weight of glass fiber. And 1 to 10 parts by weight of a reactive silicone oil in which an acrylic acid-based organic acid is introduced as a functional group at both ends.

  Secondly, in the unsaturated polyester resin composition, the mixture of unsaturated polyester resin and diallyl phthalate resin is unsaturated polyester resin / diallyl phthalate resin = 90/10 to 70/30 by weight ratio. It is characterized by.

  Thirdly, in the first or second unsaturated polyester resin composition, the basic skeleton of the reactive silicone oil is dimethylpolysiloxane.

  4thly, it is characterized by shape | molding one of the above unsaturated polyester resin compositions as a molded article.

  According to the first invention as described above, as a molding material for electrical parts such as terminals, coil bobbins, etc., for sealing electronic parts such as capacitors, coils, resistors, etc., various electrical characteristics, strength characteristics, etc. It is possible to realize an unsaturated polyester resin composition having a high balance of properties and having high heat resistance without using environmentally hazardous substances and without increasing work steps.

  According to said 2nd invention, in addition to the effect of said invention, characteristics, such as an electrical property and an intensity | strength characteristic, can be made more optimal.

  According to said 3rd invention, compatibility with resin is comparatively good, In addition to the effect of the said invention, it can be used by bleeding out to the external appearance of a molded article.

  The remarkable effects as described above are actually greatly realized as the molded article of the fourth invention.

  The present invention has the features as described above, and the best mode for carrying out the present invention will be described below.

  The unsaturated polyester resin composition of the present invention comprises 20 to 30 parts by weight of a mixture of unsaturated polyester resin and diallyl phthalate resin, 50 to 60 parts by weight of inorganic filler, 5 to 15 parts by weight of glass fiber, and acrylic at least at both ends. It is essential to contain 1 to 10 parts by weight of a reactive silicone oil in which an acid organic acid is introduced as a functional group. If any of these requirements is lacking, an unsaturated polyester resin composition having high heat resistance cannot be realized as a molding material for sealing electronic parts or electrical parts.

  When the mixture of the unsaturated polyester resin and the diallyl phthalate resin is less than 20 parts by weight, the fluidity of the unsaturated polyester resin composition is remarkably lowered and a sufficient molded product cannot be obtained. On the other hand, if it exceeds 30 parts by weight, the fluidity of the unsaturated polyester resin composition becomes too good, and a sufficient molded product cannot be obtained. Insufficient molded products may be unfilled or have voids inside, resulting in a significant decrease in heat resistance.

  The above unsaturated polyester resin is obtained by condensation reaction of a polyhydric alcohol and a dibasic acid. Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, and triethylene. Examples thereof include glycol, pentane glycol, hexanediol, neopentyl glycol, hydrogenated bisphenol A, bisphenol A, and glycerin. Examples of the dibasic acid include maleic anhydride, fumaric acid, adipic acid, phthalic anhydride, terephthalic acid, isophthalic acid, and the like. Among these, terephthalic acid and isophthalic acid are preferable in view of heat resistance. . Furthermore, it is preferable that 50% by weight or more of the unsaturated polyester resin is obtained by a condensation reaction of isophthalic acid. As a result, the thermal decomposition temperature of the resulting resin is increased, and as a result, it is considered that the heat resistance of the unsaturated polyester resin composition is affected.

  Regarding the diallyl phthalate resin, it is preferable to use a monomer and a polymer of the diallyl phthalate resin in combination. Since the monomer of the diallyl phthalate resin is a low-viscosity liquid, the fluidity of the unsaturated polyester resin composition can be adjusted by increasing or decreasing the monomer. The weight ratio of the monomer to the polymer is preferably in the range of, for example, polymer / monomer = 75/25 to 95/5, and in this range, the fluidity of the material is made suitable, and molding is performed. This is because the performance can be improved. When the polymer of diallyl phthalate resin is less than 75% by weight, the fluidity of the material becomes too large due to the influence of the relatively increasing monomer, which is not preferable. If the polymer of the diallyl phthalate resin exceeds 95% by weight, the fluidity of the material is lowered and the moldability is hindered.

  The blending ratio of the mixture of unsaturated polyester resin and diallyl phthalate resin in the present invention is not particularly limited, but for example, unsaturated polyester resin / diallyl phthalate resin = 90/10 to 70 / by weight ratio. Mixing at a ratio of 30 is considered as a preferred embodiment. Thereby, characteristics such as electrical characteristics and strength characteristics can be optimized.

  In the present invention, as described above, it is necessary to blend 50-60 parts by weight of the inorganic filler and 5-15 parts by weight of the glass fiber. By blending in such a range, the moldability is improved and the defects of the molded product are reduced, for example, the occurrence of cracks due to thermal stress during solder reflow due to the defects of the molded product is reduced. is there. When the inorganic filler is less than 50 parts by weight, the fluidity of the material increases and the moldability decreases. Furthermore, in the pressurizing and heating kneading process at the time of material production, the adhesion of the material to the kneading machine becomes large and the productivity becomes unstable. When it exceeds 60 parts by weight, the fluidity of the material is greatly reduced, and the moldability is remarkably lowered. When the glass fiber is less than 5 parts by weight, the reinforcing effect cannot be obtained. When it exceeds 15 parts by weight, the fluidity of the unsaturated polyester resin composition is lowered, and a sufficient molded product cannot be obtained.

  Examples of the inorganic filler in the present invention include fused silica, crystalline silica, alumina, quartz glass, calcium carbonate, or hydrates of metals such as aluminum hydroxide and magnesium hydroxide. As the average particle size, a particle size in the range of 2 to 40 μm can be used. Among them, it is preferable to use a hydrate of metals. This is because the hydrates of metals can impart flame resistance since the water in the molecules is removed and volatilizes around 260 ° C. For this reason, when a metal hydrate is used as the inorganic filler, flame resistance can be ensured without using a halogen compound which is an environmental load substance.

  For the glass fiber in the present invention, for example, it is considered to use a glass chop having a fiber length of about 0.1 to 5 mm in consideration of dispersibility in the material.

In the present invention, as described above, heat resistance is improved by containing 1 to 10 parts by weight of a reactive silicone oil in which an acrylic acid-based organic acid is introduced as a functional group at at least both ends. Yes. When the amount is less than 1 part by weight, the heat resistance effect cannot be obtained. If it is added in an amount exceeding 10 parts by weight, it not only deteriorates the heat resistance, but also can contaminate the mold and impair the appearance of the molded product. In addition, as for the above reactive silicone oil, the thing whose viscosity is 100 mm < ² > / s (25 degreeC) and a functional group equivalent is about 500-3000 is considered as the characteristic, for example.

  In the present invention, a reactive silicone oil in which a functional group of an acrylic acid-based organic acid is introduced at least at both ends thereof (also referred to as a both-end type) is used because the functional groups are at both ends. When it is introduced, it is continuously crosslinked and incorporated into the resin composition during the curing reaction of the resin composition. Thereby, the heat resistance improvement effect is acquired more. In the case where the functional group is introduced only at one end (also referred to as a single end type), the functional group is incorporated only at the end in the resin composition, so that a sufficient heat resistance improvement effect cannot be obtained.

  The above reactive silicone oil is a linear polymer (also referred to as straight silicone oil) whose basic skeleton is composed of siloxane bonds, and all the side chains of the polysiloxane excluding the functional groups of the organic acid introduced at both ends are all. Examples thereof include a methyl group, a part of the side chain being a phenyl group, and a part of the side chain being hydrogen. Of these, all methyl groups have relatively good compatibility with the unsaturated polyester resin and are sufficiently dispersed in the resin composition to exhibit the above-described effects. Moreover, it can be used without bleeding out to the appearance of the molded product. For this reason, dimethylpolysiloxane in which the side chains of the polysiloxane excluding the functional group of the organic acid introduced at both ends are all methyl groups is preferable. Of course, as long as a functional group of an acrylic acid-based organic acid is introduced at both ends, a functional group of an acrylic acid-based organic acid may be introduced into a part of the side chain. For example, a reactive silicone oil in which all side chains of polysiloxane are methyl groups and functional groups of acrylic acid organic acid are introduced at both ends is represented by the following formula.

式中のＲは各々同一または別異にアクリル酸系の有機酸の官能基であり、ｎは任意の整数である。

In the formula, each R is the same or different and is a functional group of an acrylic acid-based organic acid, and n is an arbitrary integer.

  In the reactive silicone oil in the present invention, the functional groups introduced at both ends thereof are acrylic acid organic acids. Examples of the acrylic acid-based organic acid include acrylic acid and methacrylic acid in the present invention. In the present invention, when the functional group of the acrylic acid organic acid is introduced, it functions as a crosslinking point for crosslinking with the unsaturated polyester resin, and the heat resistance can be further improved. In the case of other functional groups, for example, functional groups such as epoxy groups and carboxyl groups, there is no crosslinking point with the unsaturated polyester resin, and the reactive silicone oil is dispersed as a sea-island structure in the unsaturated polyester resin composition. However, it is considered that it is difficult to obtain a heat resistance effect because it merely acts as a plasticizer.

  In the present invention, various peroxides such as t-butyl peroxybenzone or 1,1-bis (t-butyl peroxy) -3,3,5-trimethyl cyclohexane are used alone or in combination of two or more as a curing agent. May be. Furthermore, if necessary, release agents such as carnauba wax, fatty acid amide, stearic acid, pigments, colorants, thickeners and the like can be added. These compounding amounts are not particularly limited, and are appropriately set according to the purpose of sealing various electronic components or molding materials for electronic components.

  The unsaturated polyester resin composition of the present invention is a mixture of an unsaturated polyester resin and a diallyl phthalate resin, an inorganic filler, glass fiber, and if necessary, a curing agent and other materials, and if necessary, After uniformly mixing with a mixer or blender, it can be prepared by heating and kneading with a kneader such as a kneader or roll. Then, the molded article of the present invention is prepared by injecting the prepared unsaturated polyester resin composition into a mold and heating and curing under conditions of a temperature of 120 to 170 ° C. and a time of 10 to 30 seconds (per 1 mm thickness of the molded article). It can be obtained by doing. This can achieve high heat resistance without using environmentally hazardous substances and without increasing the number of work processes. For sealing electronic parts such as capacitors, coils, resistors, etc., terminal blocks, coil bobbins, etc. It is suitably used as a molded product for electrical parts.

  Hereinafter, examples will be shown and described in more detail. Of course, the present invention is not limited to the following examples.

<Examples 1-8 and Comparative Examples 1-7>
In addition to the unsaturated polyester resin, diallyl phthalate resin, inorganic filler, glass fiber, reactive silicone oil in the blending amounts shown in Table 1, 4 phr dicumyl peroxide as a curing catalyst and PBQ (parabenzoquinone) as a curing inhibitor 300 ppm, and 1 wt% of carbon black as a pigment was kneaded with a pressure kneader. The kneader was kept at 40 ° C. until the kneaded product became a paste, and after the kneaded product was cooled, the kneaded product was cooled by passing cooling water and kneaded for 7 minutes. Thereafter, the kneaded product was taken out of the kneader, cooled, and pulverized with a cutter mill to obtain an unsaturated polyester resin composition.

  The unsaturated polyester resin is “Yupika 8500 Series / Nihon Iupika”, diallyl phthalate resin is “Dup Series / Daiso Chemical”, the inorganic filler is “Hajilite H32 / Showa Denko”, and the glass fiber is “fiber length 3 mm” , Fiber diameter 15 μ / manufactured by NSG-V ”was used.

  The obtained unsaturated polyester resin composition was transfer molded (mold temperature: 260 ° C., curing time: 90 seconds) to obtain a color plate (40 × 70 mm).

The color plate was evaluated for solder heat resistance.
(1) Solder heat resistance A 40 × 70 mm color plate was immersed in a solder tank by 20 mm in the longitudinal direction, and the time until the color plate bounced or cracked immediately after the immersion was measured with a stopwatch. The temperature of the solder bath is 260 ° C.

  The results are shown in Table 1.

表１の結果より、実施例１〜８では、不飽和ポリエステル樹脂とジアリルフタレート樹脂との混合物２０〜３０重量部、無機充填材５０〜６０重量部、ガラス繊維５〜１５重量部および少なくとも両末端にアクリル酸系の有機酸が官能基として導入されている反応性シリコーンオイル１〜１０重量部を含有することにより、耐熱性が良好であることが確認された。

From the results of Table 1, in Examples 1 to 8, a mixture of unsaturated polyester resin and diallyl phthalate resin 20 to 30 parts by weight, inorganic filler 50 to 60 parts by weight, glass fiber 5 to 15 parts by weight and at least both ends It was confirmed that heat resistance was good by containing 1 to 10 parts by weight of a reactive silicone oil in which an acrylic acid-based organic acid was introduced as a functional group.

  On the other hand, in Comparative Example 1, since the reactive silicone oil introduced with acrylic acid-based organic acid as a functional group at both ends is not blended, from the color plate of the unsaturated polyester resin composition in the example It was also confirmed that the heat resistance was inferior. In Comparative Example 2, the blended amount of the unsaturated polyester resin and diallyl phthalate resin and the glass fiber were 33 parts by weight and 3 parts by weight, respectively, and no reactive silicone oil was blended. It was confirmed that the heat resistance was inferior to that of the color plate of the unsaturated polyester resin composition. In Comparative Example 3, the blending amounts of the inorganic filler and the glass fiber are 48 parts by weight and 17 parts by weight, respectively. In Comparative Example 4, the blending amount of the reactive silicone oil is 12 parts by weight. It was confirmed that the heat resistance was inferior to the color plate of the unsaturated polyester resin composition in the examples. Further, in Comparative Example 5, the functional group of the acrylic acid-based organic acid introduced into the reactive silicone oil was introduced only at one end rather than at both ends (one-end type). In No. 7, it was confirmed that the heat resistance was inferior to the color plate of the unsaturated polyester resin composition in the examples because the type of functional group introduced into the reactive silicone oil was not acrylic.

Claims (4)

  Mixture of unsaturated polyester resin and diallyl phthalate resin 20 to 30 parts by weight, inorganic filler 50 to 60 parts by weight, glass fiber 5 to 15 parts by weight, and at least both ends are introduced with acrylic acid organic acid as a functional group An unsaturated polyester resin composition comprising 1 to 10 parts by weight of a reactive silicone oil.   2. The unsaturated polyester resin composition according to claim 1, wherein the mixture of the unsaturated polyester resin and the diallyl phthalate resin is unsaturated polyester resin / diallyl phthalate resin = 90/10 to 70/30 in a weight ratio. object.   The unsaturated polyester resin composition according to claim 1 or 2, wherein the basic skeleton of the reactive silicone oil is dimethylpolysiloxane.   A molded article obtained by molding the unsaturated polyester resin composition according to any one of claims 1 to 3.