JP2015127288A - Filler powder and resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filler powder that has a lower thermally expanded coefficient than that of a silica powder and, when blended into resin, causes less degeneration and discoloration of the resin.SOLUTION: A filler powder comprises a crystallized glass obtained by the deposition of β-quartz solid solution and/or β-eucryptite solid solution. Preferably, an average particle diameter Dis 5 μm or less, and a thermally expanded coefficient in the range of 30-150°C is 5×10/°C or less.

Description

  The present invention relates to a filler powder suitable for blending with a resin used for a multilayer printed wiring board or the like.

  Conventionally, an inorganic filler powder is blended into a resin for the purpose of adjusting the thermal expansion coefficient. For example, in a multilayer printed wiring board using a resin, cracks are likely to occur due to the difference in thermal expansion coefficient between the conductor layer and the insulating layer, so that it is necessary to reduce the thermal expansion coefficient of the insulating layer. Therefore, an inorganic filler powder such as silica powder is blended in the resin. Silica powder is widely used as an inorganic filler powder because of its excellent physical strength and heat resistance (see, for example, Patent Document 1).

JP 2009-88303 A

  In recent years, there has been a demand for further low thermal expansion of resin compositions. Although silica powder has a low thermal expansion coefficient to some extent, the effect of reducing the thermal expansion coefficient is still insufficient. Therefore, even if silica powder is blended with the resin, it is difficult to obtain a desired low thermal expansion coefficient. Alternatively, when a large amount of silica powder is blended in the resin in order to achieve a desired low thermal expansion coefficient, the homogeneity tends to decrease or the surface smoothness when formed into a film tends to be poor.

  Although it is conceivable to use a filler powder made of β-eucryptite crystal, β-quartz solid solution crystal, etc., which shows lower expansion characteristics than silica powder, the filler powder reacts with the resin composition to form a resin composition. There is a risk of the property being altered or discolored.

  In view of the above, an object of the present invention is to provide a filler powder that has a lower coefficient of thermal expansion than silica powder and is less likely to cause resin alteration or discoloration when blended with a resin.

  The filler powder of the present invention is characterized by comprising crystallized glass obtained by depositing β-quartz solid solution and / or β-eucryptite.

Filler powder of the present invention preferably has an average particle diameter D ₅₀ is 5μm or less.

The filler powder of the present invention preferably has a thermal expansion coefficient of 5 × 10 ⁻⁷ / ° C. or less in the range of 30 to 150 ° C.

Filler powder of the present invention, in _{mass%, SiO 2 55~75%, Al} 2 O 3 15~30%, Li 2 O 2~10%, Na 2 O 0~3%, K 2 O 0~3% _{, 0~5% MgO, 0~10% ZnO} , BaO 0~5%, TiO 2 0~5%, ZrO 2 0~4%, P 2 O 5 0~5%, and _SnO 2 0 to 2.5 It is preferable that it consists of crystallized glass containing%.

  The filler powder of the present invention preferably has a substantially spherical or substantially cylindrical shape.

  The filler powder of the present invention is preferably used by blending in a resin.

  The resin composition of the present invention is characterized by containing the filler powder and a resin.

  According to the present invention, it is possible to provide a filler powder that has a lower coefficient of thermal expansion than silica powder and is less likely to cause resin alteration or discoloration when blended with a resin.

Filler powder of the present invention, beta-quartz solid solution _{(Li 2 O · Al 2 O} 3 · nSiO 2; 2 <n ≦ 4) and / or beta-eucryptite _{(Li 2 O · Al 2 O} 3 · 2SiO 2 ), And has a low thermal expansion characteristic as compared with a silica powder conventionally used as an inorganic filler powder. Therefore, when blended in the resin, it is possible to achieve desired thermal expansion characteristics with a relatively small blending amount.

  Further, unlike the crystal powder of β-quartz solid solution or β-eucryptite, the filler powder of the present invention is composed of crystallized glass and therefore has low reactivity with the resin. For this reason, the filler powder of the present invention is characterized in that, when blended in a resin, the resin is not easily altered or discolored.

  Furthermore, since the filler powder of the present invention has a relatively small crystallite size of precipitated crystals, it can be easily pulverized. By blending finely pulverized filler powder with a small particle diameter into the resin, the resin molded body can be made thinner. In addition, when the finely pulverized crystal powder is blended with the resin as a filler powder, the thermal expansion coefficient of the obtained resin molded product tends to be larger than when the coarsely pulverized filler powder is used. On the other hand, unlike the crystalline powder, the filler powder of the present invention has a feature that the effect of reducing the coefficient of thermal expansion is hardly impaired even when pulverized.

The average particle diameter D ₅₀ of the filler powder of the present invention is preferably 5μm or less, more preferably 3μm or less, more preferably 1μm or less. The maximum particle diameter _{D 99} of the filler powder of the present invention is preferably 30μm or less, more preferably 25μm or less, more preferably 20μm or less. When the average particle diameter D ₅₀ or the maximum particle diameter D ₉₉ of the filler powder is too large, when molded by blending in a resin into a film, exposure of the filler powder in the film surface becomes prominent, poor surface smoothness Tend. Although not specifically limited lower limit of the average particle diameter D ₅₀ of the filler powder is realistically the 0.1μm or more, more is 0.2μm or more.

Incidentally, when the thickness of the resin molded body using a filler powder of the present invention is large, the average particle diameter D ₅₀ and the maximum particle diameter D ₉₉ of the filler powder is not limited to the above range. For example, a filler powder having an average particle diameter D50 of ₅₀ μm or less, further 20 μm or less, and a maximum particle diameter _D99 of 100 μm or less, further 50 μm or less can be used.

In the present invention, the average particle diameter D ₅₀ and the maximum particle diameter D ₉₉ indicate values measured by a laser diffraction method.

  The precipitation amount of β-quartz solid solution or β-eucryptite in the filler powder of the present invention is preferably 50% by mass or more, more preferably 70% by mass or more. When the precipitation amount of β-quartz solid solution or β-eucryptite is too small, it is difficult to obtain the effect of reducing the thermal expansion coefficient. On the other hand, the upper limit of the precipitation amount of β-quartz solid solution or β-eucryptite is not particularly limited, but is practically 99% by mass or less. When both β-quartz solid solution and β-eucryptite are contained, it is preferable that the total amount satisfies the above range.

The thermal expansion coefficient in the range of 30 to 150 ° C. of the filler powder of the present invention is preferably 5 × 10 ⁻⁷ / ° C. or less, more preferably 3 × 10 ⁻⁷ / ° C. or less, and 2 × 10 ⁻ More preferably, it is ⁷ / ° C. or less. The lower limit of the thermal expansion coefficient is not particularly limited, but is practically −30 × 10 ⁻⁷ / ° C. or higher, particularly −25 × 10 ⁻⁷ / ° C. or higher.

The filler powder of the present invention is not particularly limited as long as it can precipitate β-quartz solid solution and / or β-eucryptite. For example, the filler powder of the present invention, in _{mass%, SiO 2 55~75%, Al} 2 O 3 15~30%, Li 2 O 2~10%, Na 2 O 0~3%, K 2 O 0~ _{3%, 0~5% MgO, 0~10} % ZnO, BaO 0~5%, TiO 2 0~5%, ZrO 2 0~4%, P 2 O 5 0~5%, and _SnO 2 0 to 2 It is preferably made of crystallized glass containing 5%. Hereinafter, the reason why the glass composition range is limited will be described.

SiO ₂ forms a glass skeleton and is a constituent component of the main crystal. The content of SiO ₂ is preferably 55 to 75%, more preferably 60 to 75%. When the content of SiO ₂ is too small, the thermal expansion coefficient tends to increase or the chemical durability tends to decrease. On the other hand, if the content of SiO ₂ is too large, it lowered the meltability, the viscosity of the glass melt is increased, or not easily clarified, tend to or becomes difficult to mold.

Al ₂ O ₃ forms a glass skeleton and also becomes a constituent component of the main crystal. The content of Al ₂ O ₃ is preferably 15 to 30%, more preferably 17 to 27%. When the content of Al ₂ O ₃ is too small, or the thermal expansion coefficient becomes high, the chemical durability tends to lowered. On the other hand, when the content of Al ₂ O ₃ is too large, there is a tendency that the melting is lowered. Moreover, there exists a tendency for viscosity to become large and it becomes difficult to clarify or shaping | molding becomes difficult. Furthermore, it becomes easy to devitrify.

Li ₂ O is a constituent component of the main crystal and is a component that greatly affects the crystallinity and lowers the viscosity to improve the meltability and moldability. The content of Li ₂ O is preferably 2 to 10%, more preferably 2 to 7%, still more preferably 2 to 5%, and particularly preferably 2 to 4.8%. When the Li 2 _O content is too small, the main crystals may become difficult deposition, meltability or lowered. Moreover, there exists a tendency for viscosity to become large and it becomes difficult to clarify or shaping | molding becomes difficult. On the other hand, when the content of Li 2 _O is too large, it tends to be devitrified.

Na ₂ O and K ₂ O are components for reducing the viscosity and improving the meltability and moldability. The content of Na ₂ O and K ₂ O is preferably 0 to 3%, more preferably 0.1 to 1%. When the content of Na 2 _O or K _{2 O} is too large, it devitrified easily, also tends to increase the thermal expansion coefficient. Moreover, when blended with a resin, the resin may be altered.

  MgO is a component for adjusting the thermal expansion coefficient. The content of MgO is preferably 0 to 5%, more preferably 0.1 to 3%, and still more preferably 0.3 to 2%. When there is too much content of MgO, it will become easy to devitrify and a thermal expansion coefficient will become high easily.

  ZnO is a component for adjusting the thermal expansion coefficient. The content of ZnO is preferably 0 to 10%, more preferably 0 to 7%, preferably 0 to 3%, more preferably 0.1 to 1%. When there is too much content of ZnO, it will become easy to devitrify.

  BaO is a component for reducing the viscosity and improving the meltability and moldability. The content of BaO is preferably 0 to 5%, more preferably 0.1 to 3%. When there is too much content of BaO, it will become easy to devitrify.

TiO ₂ and ZrO ₂ are components that act as nucleating agents for precipitating crystals in the crystallization step. The content of TiO ₂ is preferably 0 to 5%, more preferably 1 to 4%. The content of ZrO ₂ is preferably 0 to 4%, more preferably 0.1 to 3%. When the content of TiO ₂ or ZrO ₂ is too large, it tends to be devitrified.

P ₂ O ₅ is a component that promotes phase separation and assists the formation of crystal nuclei. The content of P ₂ O ₅ is preferably 0 to 5%, more preferably 0.1 to 4%. When the content of P ₂ O ₅ is too large, tends to phase separation in the melting step, the resulting glass tends to cloudy.

SnO ₂ is a component that acts as a fining agent. The content of SnO ₂ is preferably 0 to 2.5%, more preferably 0.1 to 2%. When the content of SnO ₂ is too large, or too dark color tone, or easily devitrified.

In addition to the above components, B ₂ O ₃ , SrO, CaO and the like can be appropriately contained within a range not impairing the effects of the present invention.

The specific surface area of the filler powder of the present invention is preferably 20 m ² / g or less, more preferably 18 m ² / g or less, still more preferably 15 m ² / g or less, and 10 m ² / g or less. It is particularly preferred that When the specific surface area is too large, the filler powder is difficult to disperse in the resin, and it becomes difficult to blend the filler powder at a high concentration.

  The shape of the filler powder of the present invention is not particularly limited, but is preferably substantially spherical, substantially cylindrical or prismatic. This is preferable because the specific surface area is small even if the average particle shape of the filler powder is small. In that case, it becomes possible to mix | blend filler powder with high concentration in resin. When the shape is approximately spherical, the closer to a true sphere, the easier the effect is obtained. Moreover, when the shape is substantially columnar or prismatic, it is preferable that the aspect ratio is 10 or less because the above-described effect can be easily obtained and the mechanical strength of the obtained resin molded body can be increased.

  The filler powder of the present invention may be subjected to a surface treatment with a silane coupling agent in order to improve the wettability of the interface with the resin and the dispersibility when blended in the resin. Examples of the silane coupling agent include amino silane, epoxy silane, methacryl silane, ureido silane, and isocyanate silane.

  The filler powder of the present invention is produced as follows. First, a raw material batch obtained by blending glass raw materials at a predetermined ratio is melted to obtain molten glass. Next, bulk crystalline glass is obtained by forming the molten glass into a predetermined shape (for example, a plate shape). Furthermore, the bulk crystallized glass is obtained by heat-treating the bulk crystallized glass under predetermined conditions to precipitate β-quartz solid solution and / or β-eucryptite inside. The filler powder of the present invention can be obtained by subjecting the obtained bulk crystallized glass to a predetermined pulverization treatment. According to this method, a filler powder with a high degree of crystallinity can be easily obtained.

  The melting temperature of the raw material batch is preferably about 1600 to 1800 ° C. from the viewpoint of productivity and homogeneity. Further, the heat treatment conditions (crystallization conditions) of the crystalline glass are as follows: heat treatment at 600 to 800 ° C. for 1 to 5 hours to form crystal nuclei (crystal nucleation stage), and further at 800 to 950 ° C. It is preferable to heat-treat for 5 to 3 hours to precipitate the main crystal (crystal growth stage).

  The filler powder of the present invention is prepared by pulverizing a bulk crystalline glass obtained by molding molten glass to produce a crystalline glass powder, and then subjecting the crystalline glass powder to a heat treatment for crystallization. Can also be produced. Here, before the crystalline glass powder is crystallized, it is sprayed into a flame and subjected to heat treatment, whereby the surface of the crystalline glass powder softens and flows, and a substantially spherical filler powder can be obtained. Moreover, it becomes possible to obtain a substantially cylindrical filler powder by spinning and melting the molten glass, followed by pulverization and heat treatment.

  The filler powder of the present invention is used, for example, in a resin. A resin molded body obtained by blending the filler powder of the present invention in a resin is used as a multilayer printed wiring board or the like. Here, the resin is not particularly limited as long as it is generally used. For example, thermosetting resins such as epoxy resins, polyester resins, phenol resins, urethane resins, amino resins, polyvinyl resins, polyamide resins, polyimide resins. , Thermoplastic resins such as allyl resin, styrene resin, acrylic resin, and polycarbonate resin.

  The content of the filler powder in the resin is appropriately selected according to characteristics such as a target thermal expansion coefficient. For example, the content of the filler powder with respect to the total amount of the resin and the filler powder is suitably selected in the range of preferably 10 to 95% by volume, more preferably 20 to 90% by volume.

  The resin composition of the present invention is characterized by containing a resin and the filler powder. By carrying out like this, the thermal expansion coefficient of the resin molding formed with a resin composition can be reduced.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these Examples.

(1) Preparation of filler powder The raw material powder was prepared and mixed uniformly so that it might become the glass which has a composition of Table 1. The obtained raw material batch was melted at 1600 to 1800 ° C. until homogeneous. Molten glass was formed into a plate shape and cooled to room temperature using a slow cooling furnace to obtain a plate-like crystalline glass.

  For Examples A to H and O to Q, the plate-like crystalline glass was heat treated at 760 to 780 ° C. for 3 hours to form nuclei, and then further subjected to heat treatment at 870 to 890 ° C. for 1 hour. And crystallized. When the precipitated crystal was analyzed, it was confirmed that β-quartz solid solution was precipitated as the main crystal. About the obtained plate-shaped crystallized glass, the thermal expansion coefficient in the temperature range of 30-150 degreeC was measured using the dilatometer.

  The obtained plate-like crystallized glass was pulverized to obtain filler powders having the particle sizes shown in Tables 3, 4 and 7. As a pulverization method, coarse pulverization was performed by dry pulverization for 24 hours using a ball mill, and then the coarse powder was removed using an air classifier. The fine pulverization was performed by wet pulverization of the powder that had been dry pulverized for 24 hours using a ball mill for 66 hours.

  Moreover, about Example M and N, the crystalline glass powder obtained by grind | pulverizing plate-like crystalline glass was sprayed in the flame, and was spheroidized. Thereafter, 2 to 10% by weight of alumina fine powder was added and mixed, and after nucleation by heat treatment at 760 to 780 ° C. for 3 hours, heat treatment was further performed at 870 to 890 ° C. for 1 hour. By crystallization, a filler powder having each particle size shown in Table 6 was obtained.

(2) Evaluation With respect to the resin described in Table 2, the filler powder obtained above was blended at a predetermined ratio described in Tables 3-7. Furthermore, after adding a kneading agent and kneading, it was cured by being allowed to stand at 25 ° C. for 24 hours to obtain a resin molded body in which filler powder was dispersed. In addition, about sample IL which is a comparative example, silica glass powder or (beta) -eucryptite crystal powder was used as filler powder.

  About the resin molding, the thermal expansion coefficient in the temperature range of 30-150 degreeC was measured with the TMA measuring apparatus. The color tone was also evaluated visually. The results are shown in Tables 3-7.

(3) Discussion of results In Examples E to H in which the filler content was 50% by volume, the thermal expansion coefficient of the resin molding was 690 to 715 × 10 ⁻⁷ / ° C. No. whose thermal expansion coefficient is −20 × 10 ⁻⁷ / ° C. or less. In Examples O to Q using the filler having the composition of 3 to 5, the thermal expansion coefficient of the resin molded body was further reduced to 660 to 675 × 10 ⁻⁷ / ° C. On the other hand, Comparative Examples I and J, in which the filler content was 50% by volume and silica glass was used as the filler powder, had a thermal expansion coefficient of 770 to 780 × 10 ⁻⁷ / ° C. Therefore, it can be seen that the filler powder of the present invention has a greater effect of lowering the thermal expansion coefficient when blended in the resin than the filler powder made of silica glass.

In Examples M and N, in which the filler content was 60% by volume, the thermal expansion coefficient of the resin molding was 520 to 530 × 10 ⁻⁷ / ° C. In these cases, since the particle shape is spheroidized, the specific surface area is reduced, the content relative to the resin can be increased, and the thermal expansion coefficient of the resin molded body can be further reduced.

  In Examples A to H and M to Q using the filler powder of the present invention, the resin molded product had a desired milky white color tone. Moreover, since the refractive index difference with resin is smaller than silica glass, translucency was shown. On the other hand, in Comparative Examples K and L using β-eucryptite crystal powder as the filler powder, the color tone of the resin molding was brown, and the resin was discolored. Thus, it turns out that the filler powder of this invention can suppress discoloration of resin at the time of mix | blending in resin.

In Examples E to H, M, and N, when the finely pulverized filler powder was used, the difference in the thermal expansion coefficient of the resin molded body was small compared to the case of using the coarsely pulverized filler powder (Δα ( Fine grinding-coarse grinding) is -5 to + 10 × 10 ⁻⁷ / ° C.). On the other hand, in Comparative Examples K and L using β-eucryptite crystal powder as the filler powder, the resin molded body was compared with the case where the finely pulverized filler powder was used and the case where the coarsely pulverized filler powder was used. The thermal expansion coefficient is significantly increased (Δα (fine pulverization-coarse pulverization) is + 80 × 10 ⁻⁷ / ° C.). Thus, it can be seen that even if the filler powder of the present invention is finely pulverized, the effect of reducing the coefficient of thermal expansion is hardly impaired. This is presumably because the filler powder of the present invention has a very small crystal size.

Claims (7)

  A filler powder comprising a crystallized glass obtained by precipitating β-quartz solid solution and / or β-eucryptite. 2. The filler powder according to claim 1, wherein the average particle diameter D ₅₀ is 5 μm or less. The filler powder according to claim 1 or 2, wherein a thermal expansion coefficient in a range of 30 to 150 ° C is 5 × 10 ^-7 / ° C or less. By _{mass%, SiO 2 55~75%, Al} 2 O 3 15~30%, Li 2 O 2~10%, Na 2 O 0~3%, K 2 O 0~3%, 0~5% MgO, _{0~10% ZnO, BaO 0~5%,} TiO 2 0~5%, ZrO 2 0~4%, crystallized glass containing _P 2 O 5 _0~5%, and _SnO 2 0 to 2.5% The filler powder according to any one of claims 1 to 3, wherein the filler powder is made of.   The filler powder according to any one of claims 1 to 4, wherein the shape is substantially spherical or substantially cylindrical.   It mix | blends and uses for resin, The filler powder as described in any one of Claims 1-5 characterized by the above-mentioned.   A resin composition comprising the filler powder according to any one of claims 1 to 5 and a resin.