JP2017088642A - filler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filler capable of providing a silicone resin composition that, when blended with silicone resin, adds high thermal conductivity, and also has excellent workability and flexibility.SOLUTION: A filler for silicone resin has inorganic oxide powder surface-treated with titanate coupling agent.SELECTED DRAWING: None

Description

  The present invention relates to a filler for silicone resin. More specifically, the present invention relates to a filler filled in a silicone resin, including an inorganic oxide powder surface-treated with a titanate coupling agent, a silicone resin composition containing the filler, and a method for producing the filler. .

  Electronic components such as CPUs (Central Processing Units) and transistors that constitute parts of electronic equipment such as computers may cause deterioration of the functions of electronic equipment due to heat generation during use. A heat radiating sheet is provided between an electronic component serving as a heat generating body and a heat radiating body such as a heat radiating fin. Conventionally, as a composition for constituting such a heat-dissipating sheet, a resin composition composed of a silicone resin or the like blended with a heat conductive filler such as aluminum oxide in order to increase the heat conductivity has been used.

  However, when a large amount of thermally conductive filler is blended in order to increase the thermal conductivity, the hardness of the molded body made of such a resin composition is increased, so that the adhesion to electronic parts and heat sinks is reduced. There has been a problem that the heat dissipation effect cannot be sufficiently obtained, and the workability when processing into a heat dissipation sheet is deteriorated due to the increase in the viscosity of the resin composition.

  In recent years, various resin compositions have been proposed in order to solve such problems. For example, Patent Document 1 includes a thermally conductive filler such as aluminum oxide surface-treated with a silane coupling agent and a silicone gel. A thermally conductive silicone gel composition is disclosed. Similarly, Patent Document 2 discloses a heat conductive resin composition containing a heat conductive inorganic powder such as alumina coated with a silane compound and silicone rubber. Patent Document 3 discloses a heat conductive rubber that does not use silicone rubber, includes a base rubber mainly composed of polar rubber such as acrylic rubber, a filler such as aluminum oxide, and further contains a titanate coupling agent. A composition is disclosed.

JP 2001-329173 A Japanese Patent No. 4514164 JP 2012-211250 A

However, even in the heat conductive resin composition as described in Patent Documents 1 to 3, the viscosity and hardness are not always satisfactory.
An object of the present invention is to provide a filler capable of providing a silicone resin composition having high heat conductivity and excellent workability and flexibility when blended with a silicone resin. It is.

The present invention provides the following preferred embodiments [1] to [9].
[1] A filler for a silicone resin comprising an inorganic oxide powder surface-treated with a titanate coupling agent.
[2] The filler according to [1], wherein the inorganic oxide powder has a BET specific surface area of 0.1 m ² / g or more and 8 m ² / g or less.
[3] The filler according to [1] or [2], wherein the inorganic oxide powder is aluminum oxide.
[4] Use of an inorganic oxide powder surface-treated with a titanate coupling agent as a filler filled in a silicone resin.
[5] A silicone resin composition comprising the filler according to any one of [1] to [3] and a silicone resin.
[6] A silicone resin molded article comprising the silicone resin composition according to [5].
[7] A method for producing a filler for a silicone resin, comprising surface-treating an inorganic oxide powder with a titanate coupling agent.
[8] The production method according to [7], wherein the surface treatment is performed with a titanate coupling agent in an amount of 0.1 to 2.4 parts by mass with respect to 100 parts by mass of the inorganic oxide powder.
[9] The production method according to [7] or [8], wherein the surface treatment is performed at a temperature of 60 ° C. or higher.

  ADVANTAGE OF THE INVENTION According to this invention, when mix | blending with respect to a silicone resin, while providing high thermal conductivity, the filler which can provide the silicone resin composition which has the outstanding workability and a softness | flexibility can be provided.

Hereinafter, embodiments of the present invention will be described in detail.
The filler of the present invention is a filler that is suitable for being filled into a silicone resin and includes an inorganic oxide powder surface-treated with a titanate coupling agent. By directly surface-treating the inorganic oxide powder with a titanate coupling agent, the affinity of the inorganic oxide powder for the silicone resin can be increased.

As the titanate coupling agent used in the present invention, for example, the formula (1):
(X) _n- Ti- (Z) _m [L] _q (1)
[In the formula, Z represents a hydrophobic organic functional group, X represents a hydrolyzable group, L represents a ligand, m is a number of 1 to 4, and n is a number of 1 to 4. , Q is a number from 0 to 2. However, when q is 2, m may be 0. ]
And the like.

  The “hydrolyzable group” represented by X in the formula (1) is a monovalent or polyvalent hydrolyzable group having 1 to 7 carbon atoms and comprising a hydrocarbon group and an oxygen atom. And a group bonded to Ti by 1 or 2 oxygen atoms is preferred. Examples of such hydrolyzable groups include the following groups.

  n is a number from 1 to 4, and is usually 1 or 2. The smaller the number of hydrolyzable groups, the more the titanate coupling agents can be prevented from condensing when bonded to the hydroxyl group present on the particle surface of the inorganic oxide powder.

  The “hydrophobic organic functional group” represented by Z in formula (1) is preferably a hydrophobic organic functional group having a large number of carbon atoms, a hydrocarbon carboxy group having 8 to 20 carbon atoms, or the number of carbon atoms. The hydrogen atom is removed from the hydroxyl group of the hydrocarbon oxy group having 8 to 20 carbon atoms, the sulfonyloxy group having 8 to 20 carbon atoms, the metaphosphate ester having 8 to 40 carbon atoms or the pyrophosphate ester having 8 to 40 carbon atoms. More preferred. The sulfonyloxy group having 8 to 20 carbon atoms is preferably a phenylsulfonyloxy group in which a hydrocarbon group having 2 to 14 carbon atoms is bonded to the 4-position. The metaphosphate ester having 8 to 40 carbon atoms is preferably a metaphosphate ester having 1 to 2 hydrocarbon oxy groups having 1 to 2 carbon atoms bonded to a metaphosphate residue. The pyrophosphate ester having 8 to 40 carbon atoms is preferably a pyrophosphate ester in which 1 to 2 hydrocarbon oxy groups having 2 to 8 carbon atoms are bonded to a pyrophosphate residue. Examples of such hydrophobic organic functional groups include the following groups.

  By using a titanate coupling agent having a hydrophobic organic functional group having a large number of carbon atoms, the affinity of the inorganic oxide powder for the silicone resin can be further increased.

  m is a number from 1 to 4, and is usually 2 or 3. Since the affinity of the inorganic oxide powder to the silicone resin can be improved as the number of hydrophobic organic functional groups increases, m is particularly preferably 3. However, when q is 2, m may be 0.

  The ligand represented by L in Formula (1) is an atomic group coordinated to a Ti atom, and a phosphite compound having 8 to 40 carbon atoms is preferable. Examples of the ligand include dioctyl phosphite and ditridecyl phosphite represented by the following structural formula.

  q is a number from 0 to 2, and when q = 0, it means that the ligand is not bonded.

  Specific examples of such titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri (N-aminoethyl / aminoethyl) titanate, diisopropyl bis (dioctyl phosphate) titanate, and tetraisopropyl bis (dioctyl phosphite). ) Titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl phosphite) titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctyl) Pyrophosphate) ethylene titanate and the like. Of these, isopropyl triisostearoyl titanate is preferable as the titanate coupling agent from the viewpoint of affinity with the silicone resin. These titanate coupling agents may be used alone or in combination of two or more.

  The inorganic oxide powder contained in the filler of the present invention can be prepared by subjecting the inorganic oxide powder as a raw material to a surface treatment with the titanate coupling agent. Hereinafter, the surface treatment of the inorganic oxide powder contained in the filler of the present invention will be described. In addition, this invention also provides the manufacturing method of the filler for silicone resins including surface-treating the inorganic oxide powder described below with a titanate coupling agent.

The inorganic oxide powder used as a raw material in the present invention preferably has a BET specific surface area of 0.1 m ² / g or more and 8 m ² / g or less, and is 0.3 m ² / g or more and 4 m ² / g or less. Is more preferable. When the inorganic oxide powder used as a raw material has a BET specific surface area of 0.1 m ² / g or more, each particle of the inorganic oxide powder has a hydroxyl group capable of binding to a hydrolyzable group of the titanate coupling agent. Since it exists sufficiently on the surface, the effect of surface treatment with the titanate coupling agent can be sufficiently obtained, and the affinity of the inorganic oxide powder for the silicone resin can be further increased. Moreover, when the BET specific surface area of the inorganic oxide powder used as a raw material is 8 m ² / g or less, the generation of aggregated particles during the surface treatment can be effectively suppressed. By using the inorganic oxide powder having the BET specific surface area as a raw material, an inorganic oxide powder having a BET specific surface area of usually 0.1 m ² / g or more and 8 m ² / g or less is obtained after the surface treatment. It is done.

In the present invention, the center particle diameter of the inorganic oxide powder used as a raw material is preferably 0.1 to 100 μm, and more preferably 1 to 20 μm. When the center particle size of the inorganic oxide powder as the raw material is within the above range, the surface treatment effect by the titanate coupling agent can be sufficiently obtained, and the generation of aggregated particles during the surface treatment can be suppressed. Can do.
The central particle size can be measured using a laser diffraction / scattering particle size distribution measuring device such as Microtrac MT3300 (manufactured by Nikkiso Co., Ltd.).

  In the present invention, the inorganic oxide powder is not particularly limited as long as it has thermal conductivity, and may be a conventionally known inorganic oxide powder, such as aluminum oxide, titanium oxide, silicon oxide. And powders such as magnesium oxide and zinc oxide. Among them, the inorganic oxide powder in the present invention is preferably an aluminum oxide powder because of its high thermal conductivity and low cost.

  When aluminum oxide is used as the inorganic oxide powder, any of aluminum oxide such as α-alumina, γ-alumina, and amorphous may be used. From the viewpoint of improving thermal conductivity, α-alumina is preferably used. The manufacturing method of the aluminum oxide used as a raw material is not specifically limited, It can manufacture using the method generally used conventionally. For example, aluminum hydroxide obtained by the alkoxide method, Bayer method, ammonium alum pyrolysis method, ammonium dosonite pyrolysis method, etc. is produced by firing in air at a temperature of 1100 ° C. or higher. It can be used as aluminum oxide as a raw material. Further, when pulverizing the aluminum oxide as a raw material, for example, alcohols such as methanol, ethanol and propanol, glycols such as ethylene glycol and propylene glycol, and the like can be used as a pulverization aid.

  When aluminum oxide is used as the inorganic oxide powder in the present invention, the shape of aluminum oxide is not particularly limited. For example, aluminum oxide having a spherical shape, a polyhedron shape, an irregular shape, a fiber shape, a plate shape, or the like is used. Can be used.

  For the surface treatment of the inorganic oxide powder with the titanate coupling agent, either a dry method or a wet method can be employed. For example, after mixing inorganic oxide powder and a titanate coupling agent with a blender etc., it can carry out by heat-processing. Specifically, mixing of the inorganic oxide powder and the titanate coupling agent can be performed by stirring and mixing using a known stirring mixer such as a Henschel mixer or a super mixer. Further, by using a stirring mixer with a jacket temperature controller, the inorganic oxide powder and the titanate coupling agent can be stirred and mixed while heating.

  The amount of the titanate coupling agent used for the surface treatment is preferably 0.1 parts by mass or more and 2.4 parts by mass or less, and 0.5 parts by mass or more and 2.0 parts by mass or less with respect to 100 parts by mass of the inorganic oxide powder. More preferably, it is 0.9 parts by mass or more and 2.0 parts by mass or less, and particularly preferably 1.5 parts by mass or more and 2.0 parts by mass or less. When the amount of the titanate coupling agent used for the surface treatment is within the above range, the titanate coupling agent is sufficiently bonded to the surface of the inorganic oxide powder, so that the inorganic oxide powder has a high affinity for the silicone resin. Can be obtained. By filling the silicone resin with a filler containing such inorganic oxide powder, a silicone resin composition having low hardness when molded can be obtained. In particular, a filler containing a surface-treated inorganic oxide powder with a sufficient amount (for example, 0.5 parts by mass or more with respect to 100 parts by mass of the inorganic oxide powder) is used as a silicone resin. When filled, the resulting silicone resin composition exhibits a lower viscosity and has excellent processability. On the other hand, when the amount of titanate coupling agent used for the surface treatment is too large, the silicone resin composition may be inhibited from curing.

  In this invention, it is preferable to heat-process in the surface treatment of the inorganic oxide powder by a titanate coupling agent. In the heat treatment in the surface treatment, after mixing the inorganic oxide powder and the titanate coupling agent, the mixture may be subjected to a heat treatment, or the inorganic oxide powder and the titanate coupling agent are mixed. You may heat-process, however. The heating temperature is preferably 60 ° C. or higher, more preferably 90 ° C. or higher, further preferably 120 ° C. or higher, and particularly preferably 150 ° C. or higher. By performing the heat treatment in the surface treatment of the inorganic oxide powder with the titanate coupling agent, the titanate coupling agent used for the surface treatment can be sufficiently reacted, and the amount of the unreacted titanate coupling agent is reduced. can do. Thereby, the silicone resin composition which becomes low hardness when it shape | molds can be obtained. In particular, when the heating temperature is moderately high (for example, 90 ° C. or higher), the silicone resin composition tends to exhibit lower viscosity when filled into the silicone resin, and has excellent processability. Although the upper limit of heating temperature is not specifically limited, Usually, it is 200 degrees C or less, and it is preferable that it is 150 degrees C or less.

  For example, when the heat treatment is performed while mixing the inorganic oxide powder and the titanate coupling agent, a predetermined amount of the inorganic oxide powder and the titanate coupling agent are charged into a mixer with a jacket temperature controller, The mixture can be stirred and mixed while heating until the powder temperature of the mixture reaches a predetermined heating temperature. Alternatively, after a predetermined amount of inorganic oxide powder is charged into a mixer, stirring and mixing may be performed while heating until the powder temperature of the mixture reaches a predetermined heating temperature while adding a titanate coupling agent. After the powder temperature reaches a predetermined heating temperature, the powder temperature may be further heated for a certain time. The heating time after the powder temperature reaches a predetermined heating temperature may be appropriately determined according to the heating temperature and the type and amount of the inorganic oxide powder and titanate coupling agent subjected to the heat treatment. It may be 30 minutes, preferably 5 to 20 minutes.

  When heat treatment is performed after mixing the inorganic oxide powder and the titanate coupling agent, the mixture of the inorganic oxide powder and the titanate coupling agent is heated using, for example, an air circulation oven or an electric furnace. can do. The heating time may be appropriately determined according to the heating temperature and the kind and amount of the inorganic oxide powder and titanate coupling agent to be heat-treated, and may be, for example, 5 to 120 minutes, for example, 30 to 90 minutes. Preferably there is.

  The inorganic oxide powder subjected to the heat treatment is usually recovered after cooling. For example, the inorganic powder after the heat treatment may be cooled by transferring it to a water-cooled mixer, or may be naturally cooled outside the apparatus such as a mixer or a heating device.

  Since the inorganic oxide powder surface-treated with the titanate coupling agent has a high affinity for the silicone resin, it is excellent in familiarity with the silicone resin when filled with the silicone resin. For this reason, the said inorganic oxide powder surface-treated with the titanate coupling agent can be used suitably as a filler used with respect to a silicone resin.

  The filler of the present invention may be composed only of inorganic oxide powder surface-treated with a titanate coupling agent, and if the range does not affect the effect of the filler of the present invention, In addition to the inorganic oxide powder, an additive that can be generally blended with a filler used for the silicone resin may be included.

  Since the filler of the present invention has a high affinity for the silicone resin, it is excellent in familiarity with the silicone resin when filled in the silicone resin. For this reason, the filler of the present invention has a viscosity of the silicone resin composition as compared with a filler such as a thermally conductive filler surface-treated with, for example, a silane coupling agent as generally used conventionally. An increase in the hardness of the molded body can be suppressed. Therefore, the filler of the present invention can be suitably used as a filler for obtaining a silicone resin composition excellent in processability and flexibility. Accordingly, the present invention also provides a silicone resin composition comprising the filler of the present invention and a silicone resin.

  The silicone resin contained in the silicone resin composition of the present invention is not particularly limited and can be appropriately selected depending on the purpose. Examples of the silicone resin include addition reaction type liquid silicone resins and condensation reaction type silicone resins. These silicone resins may be used alone or in combination of two or more. Among the silicone resins, an addition reaction type liquid silicone resin is preferable because the silicone resin composition can exhibit high flexibility.

  Specific examples of the addition reaction type liquid silicone resin include, for example, one solution of an organopolysiloxane having a vinyl group at the terminal or side chain, and an organopolysiloxane having two or more H-Si groups at the terminal or side chain. A two-component addition reaction type liquid silicone resin in which is used as a two-component liquid. As such an addition reaction type liquid silicone resin, commercially available products may be used, and examples thereof include CY52-276 and 527 manufactured by Toray Dow Corning Co., Ltd. In the silicone resin composition of the present invention, when the two-component addition reaction type liquid silicone resin is used, the mixing ratio of the first and second liquids is the desired viscosity of the silicone resin composition and the desired viscosity when cured. What is necessary is just to select suitably according to hardness etc.

  The silicone resin composition of the present invention preferably contains the filler of the present invention in an amount of 300 to 1000 parts by mass, preferably 400 to 700 parts by mass with respect to 100 parts by mass of the total amount of silicone resin contained in the silicone resin composition. Is more preferable. When the amount of the filler of the present invention contained in the silicone resin composition is within the above range, a molded product having low hardness and high thermal conductivity can be obtained by the silicone resin composition.

  The silicone resin composition of the present invention is generally used for the silicone resin composition as long as it does not affect the effect of the silicone resin composition of the present invention in addition to the filler and silicone resin of the present invention. Ingredients that can be blended may be included. As a component which the silicone resin composition of this invention may contain, a coloring agent etc. are mentioned, for example.

  The silicone resin composition of the present invention can be produced by a method known in the art. Specifically, for example, the silicone resin and the filler of the present invention can be prepared by charging a predetermined amount in a kneader such as a planetary mixer and kneading under normal pressure or reduced pressure. Moreover, the silicone resin composition can be obtained by placing the silicone resin composition of the present invention in a mold and heating and curing it at a predetermined temperature and time. What is necessary is just to determine suitably the temperature at the time of mixing, a pressure, mixing time, the temperature at the time of shaping | molding, time, etc. according to the kind of silicone resin to be used, the quantity of a silicone resin, and a filler.

  The silicone resin composition containing the inorganic oxide powder, the titanate coupling agent and the silicone resin is not subjected to surface treatment directly with the titanate coupling agent on the inorganic oxide powder before mixing with the silicone resin. It can also be prepared by adding a titanate coupling agent when the inorganic oxide powder and the silicone resin are kneaded. However, in this method, the affinity of the inorganic oxide powder to the silicone resin is low, and it tends to be difficult to knead the silicone resin and the inorganic oxide powder. Has high hardness and poor flexibility. Therefore, the silicone resin composition of the present invention comprises an inorganic oxide powder directly surface-treated with a titanate coupling agent and a silicone resin, and kneaded and molded to obtain the silicone resin molded article of the present invention. It is done.

The silicone resin composition of the present invention is a low-viscosity resin composition. Therefore, for example, it has a viscosity of 1500 to 3000 Pas, preferably 1500 to 2500 Pas. By having the viscosity in the above range, the silicone resin composition of the present invention is easy to handle and excellent in workability.
In addition, the said viscosity of a silicone resin composition is the value measured by the method shown by the Example mentioned later.

The silicone resin molded article obtained from the silicone resin composition of the present invention is a molded article having a low hardness. Therefore, for example, it has an Asker C hardness of 5 to 40, preferably 5 to 30. By having the hardness in the above range, the silicone resin composition of the present invention and the molded product thereof are excellent in flexibility. Therefore, for example, a heat radiating sheet manufactured using the silicone resin composition of the present invention has excellent adhesion to electronic components and heat radiating bodies, and has a high heat radiating effect.
In addition, the said hardness of a silicone resin molded object is the value measured by the method shown by the Example mentioned later.

  Moreover, the silicone resin composition of the present invention and the molded product thereof have high thermal conductivity. Therefore, for example, it has a thermal conductivity of 0.5 to 3 W / m · K, preferably 1 to 3 W / m · K.

  The silicone resin composition and molded product thereof according to the present invention have excellent processability and flexibility, and have high thermal conductivity. Therefore, the silicone resin composition and the molded body thereof can be suitably used as a material such as a heat radiating sheet used in electronic devices. it can.

  Hereinafter, the present invention will be described more specifically with reference to examples. The scope of the present invention is not limited to the contents of the following examples.

1. Example 1
(1) Preparation of filler <Surface treatment of aluminum oxide>
According to the composition shown in Table 1, with respect to 100 parts by mass of aluminum oxide A [AL-41DBM-01 (manufactured by Sumitomo Chemical Co., Ltd.), center particle size: 1.3 μm, BET specific surface area: 2.6 m ² / g] 0.9 parts by mass of titanate coupling agent [Plenact TTS (Ajinomoto Fine Techno Co., Ltd.)] was added and mixed with a blender (WARING X-TREME model number: MX1200XTM). Subsequently, according to the conditions shown in Table 1, the obtained mixture was subjected to a surface treatment by heat treatment at 150 ° C. for 90 minutes in an air circulation oven to obtain a filler 1.

(2) Preparation of silicone resin composition and molded body thereof According to the method described in Japanese Patent No. 5192955, a silicone resin composition was prepared, and the molded body was obtained from the silicone resin composition. That is, 500 parts by mass of the filler 1 (surface-treated aluminum oxide A) obtained by the surface treatment is added to 100 parts by mass of the silicone resin “CY52-276” (manufactured by Toray Dow Corning Co., Ltd.) as the silicone resin. The mixture was mixed under normal temperature and normal pressure for 3 minutes using a vacuum defoaming Mikista 250 type (manufactured by Mikista Kogyo Co., Ltd.). Thereafter, the air in the mixture was evacuated for 10 minutes under reduced pressure to obtain a silicone resin composition 1.
The obtained silicone resin composition 1 is put into a 30 mmφ × 3 mm mold, molded using a press molding machine, and then cured by heating at 100 ° C. for 60 minutes to obtain a silicone resin molded body 1. It was.
The thermal conductivity and hardness of the obtained silicone resin molding 1 were measured according to the following method. The results are shown in Table 2.

<Measurement of thermal conductivity>
The thermal conductivity was measured with a hot disk method thermophysical property measuring apparatus (model number: TPS2500S, manufactured by Kyoto Electronics Industry Co., Ltd.). A 4 mmφ sensor was sandwiched between the silicone resin moldings 1 and set in a jig. Thereafter, the cover attached to the jig was covered so as not to be exposed to wind, and the thermal conductivity was measured.

<Asker C hardness>
Hardness was measured by applying two loads of the molded body obtained above and applying a load of 1 kgf using an Asker C hardness meter.

  On the other hand, 500 parts by mass of the filler 1 obtained by the surface treatment is added to 100 parts by mass of silicone resin “SH200-300CS” (manufactured by Toray Dow Corning Co., Ltd.) as a silicone resin, and vacuum is added. Using a defoamed Mikista 250 type (manufactured by Mikista Kogyo Co., Ltd.), the mixture was mixed at room temperature and normal pressure for 1 minute to obtain a silicone resin composition 1 ′ for viscosity evaluation. The obtained silicone resin composition 1 ′ was transferred to a container for viscosity measurement, immersed in a water bath at 25 ° C. for 30 minutes, and then the viscosity was measured using a B-type viscometer (model number: RB85H, manufactured by Toki Sangyo Co., Ltd.). It was 2032 Pas when measured under the conditions: 25 ° C., spindle No. 7, rotation speed 0.5 rpm.

2. Example 2
As shown in Table 1, the filler and silicone resin were prepared in the same manner as in Example 1 except that the amount of titanate coupling agent used for the surface treatment was 0.5 parts by mass with respect to 100 parts by mass of aluminum oxide. A composition and a silicone resin molded body were prepared. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2. Furthermore, when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as in Example 1, it was 2632 Pas.

3. Example 3
As shown in Table 1, a filler, a silicone resin composition, and a silicone resin molded article were prepared by the same method as in Example 1 except that the heating temperature in the surface treatment was changed to 120 ° C. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2. Furthermore, when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as in Example 1, it was 2112 Pas.

4). Example 4
As shown in Table 1, the filler and silicone resin were prepared in the same manner as in Example 1 except that the amount of titanate coupling agent used for the surface treatment was 1.5 parts by mass with respect to 100 parts by mass of aluminum oxide. A composition and a silicone resin molded body were prepared. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2. Furthermore, it was 1680 Pas when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as Example 1.

5. Example 5
As shown in Table 1, the filler and silicone resin were prepared in the same manner as in Example 1 except that the amount of titanate coupling agent used for the surface treatment was 2.0 parts by mass with respect to 100 parts by mass of aluminum oxide. A composition and a silicone resin molded body were prepared. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2. Furthermore, when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as in Example 1, it was 1752 Pas.

6). Example 6
As shown in Table 1, a filler, a silicone resin composition, and a silicone resin molded article were prepared in the same manner as in Example 1 except that the heating temperature in the surface treatment was changed to 90 ° C. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2. Furthermore, when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as in Example 1, it was 2440 Pas.

7). Example 7
As shown in Table 1, the filler and silicone resin were prepared in the same manner as in Example 1 except that the amount of titanate coupling agent used for the surface treatment was 0.1 parts by mass with respect to 100 parts by mass of aluminum oxide. A composition and a silicone resin molded body were prepared. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2.

8). Example 8
As shown in Table 1, the filler and silicone resin were prepared in the same manner as in Example 1 except that the amount of titanate coupling agent used for the surface treatment was 0.3 parts by mass with respect to 100 parts by mass of aluminum oxide. A composition and a silicone resin molded body were prepared. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2.

9. Example 9
As shown in Table 1, a filler, a silicone resin composition, and a silicone resin molded article were prepared in the same manner as in Example 1 except that no heat treatment was performed in the surface treatment. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2.

10. Example 10
As shown in Table 1, a filler, a silicone resin composition, and a silicone resin molded article were prepared by the same method as in Example 1 except that the heating temperature in the surface treatment was changed to 60 ° C. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 2.

11. Comparative Example 1
As shown in Table 3, using a surface-treated aluminum oxide A as a filler, a silicone resin composition was prepared in the same manner as in Example 1. As shown in Table 4, the aluminum oxide and the silicone resin were The affinity of was poor, and it was not possible to knead both.

12 Comparative Example 2
The surface treatment of aluminum oxide was not performed directly with the titanate coupling agent, and the titanate coupling agent was added to the aluminum oxide A used in Example 1 in an amount of 0. A silicone resin composition was prepared by adding 9 parts by mass and kneading under the same conditions as in Example 1. As shown in Table 4, the affinity between aluminum oxide and silicone resin was poor, and both were kneaded. I couldn't.

13. Comparative Example 3
As shown in Table 3, in the surface treatment of aluminum oxide, 0.7 parts by mass of hexyltrimethoxysilane [Z6583 (manufactured by Toray Dow Corning)] instead of titanate coupling agent was added to 100 parts by mass of aluminum oxide. Except for the above, a filler, a silicone resin composition, and a silicone resin molded article were prepared in the same manner as in Example 1. By the same method as in Example 1, the thermal conductivity and Asker C hardness of the silicone resin molded body were measured. The results are shown in Table 4. Furthermore, when the viscosity of the silicone resin composition for viscosity evaluation was measured by the same method as in Example 1, it was 2272 Pas.

  As shown in Table 2, when inorganic oxide powder (aluminum oxide) directly surface-treated with a titanate coupling agent is used as a filler for silicone resin (Examples 1 to 10), the resulting silicone The hardness of the molded body of the resin composition was low. In addition, when the surface treatment of aluminum oxide was performed using a specific amount of titanate coupling agent and when heat treatment was performed at a constant temperature during the surface treatment, a lower viscosity silicone resin composition was obtained (implementation) Examples 1-6). On the other hand, as shown in Table 4, when the surface treatment of aluminum oxide was not performed (Comparative Example 1), and the surface treatment was not performed directly on the aluminum oxide, the titanate coupling agent was added when mixed with the silicone resin. When added (Comparative Example 2), the affinity between the silicone resin and aluminum oxide was low, and the two could not be kneaded. Moreover, when the surface treatment was performed with a silane coupling agent (Comparative Example 3), it was confirmed that the hardness of the silicone resin molded body was high and the flexibility was poor.

Claims (9)

  The filler for silicone resins containing the inorganic oxide powder surface-treated with the titanate coupling agent. The filler according to claim 1, wherein the inorganic oxide powder has a BET specific surface area of 0.1 m ² / g or more and 8 m ² / g or less.   The filler according to claim 1 or 2, wherein the inorganic oxide powder is aluminum oxide.   Use of an inorganic oxide powder surface-treated with a titanate coupling agent as a filler filled in a silicone resin.   The silicone resin composition containing the filler and silicone resin in any one of Claims 1-3.   A silicone resin molded article comprising the silicone resin composition according to claim 5.   The manufacturing method of the filler for silicone resins including surface-treating inorganic oxide powder with a titanate coupling agent.   The manufacturing method of Claim 7 which performs the said surface treatment with the titanate coupling agent of the quantity of 0.1 to 2.4 mass parts with respect to 100 mass parts of inorganic oxide powder.   The manufacturing method of Claim 7 or 8 which performs the said surface treatment under the temperature of 60 degreeC or more.