JP2002313621A - Silicone resin composition and resin-bonded molded metallic parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicone resin composition that can prevent the attenuation of its permeability in a high-frequency region while maintaining a permeability value when a small amount of bonding resin is added to the composition, and to provide resin-bonded molded metallic parts that are obtained by curing the resin composition and can be used in a wide frequency region. SOLUTION: The silicone resin composition contains a silicone resin (a), metal or metallic compound powder (b), and a silane coupling agent (c).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicone resin composition which provides a resin-bonded metal molded product having excellent magnetic permeability, and a metal molded product using the same.

[0002]

2. Description of the Related Art A part of electric and electronic parts such as a toroidal core and a choke coil for a noise filter, a deflection yoke for an electron beam, a magnetic core of a transformer and a high-frequency part, and a magnetic head are made of magnetic metal powder using resin as a binder. There is a resin-bonded metal molding type obtained by compacting. In recent years, in addition to demands for miniaturization and thinning of various parts, molded parts having excellent magnetic permeability characteristics have been demanded for the above-mentioned resin-bonded metal molded parts under a higher operating frequency. However, the permeability characteristics largely depend on the binder resin used, and there is still insufficient research on binder resins that can provide excellent permeability characteristics for miniaturization, thinning, and use in high-frequency regions. Is not obtained.

[0003]

In resin-bonded metal molding, the addition of a large amount of a binder resin has the advantage that the attenuation of magnetic permeability in a high-frequency region can be suppressed, but conversely, the value of magnetic permeability is reduced. I have a situation. An object of the present invention is to provide a resin composition capable of preventing a decrease in magnetic permeability in a high-frequency region while maintaining a magnetic permeability value by adding a small amount of a binding resin, and a resin obtained by curing the resin composition. The purpose of the present invention is to provide a resin composition capable of achieving use in a wide frequency range.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention. That is, the present invention provides a silicone resin composition comprising (1) a silicone resin (a), a metal or metal compound powder (b), and a silane coupling agent (c);
(2) The silicone resin has the following formula (1)

Embedded image (In the formula, n represents an integer of 10 to 30. Further, R is
It represents any one of a hydrogen atom, a methyl group, an ethyl group, a t-butyl group and a phenyl group, and may be the same or different. ), Wherein the powder (b) of the metal or metal compound (3) is a powder containing a metal or metal compound exhibiting magnetism. The silicone resin composition according to the above (3), wherein the metal or metal compound exhibiting magnetism contains at least an iron component; and (5) the silicone resin composition according to the above (1) to (4). A resin-bonded metal molded part using the silicone resin composition according to any one of the preceding claims.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The silicone resin composition of the present invention contains a silicone resin (a), a powder of a metal or a metal compound (b), and a silane coupling agent (c). The silicone resin (a) used in the present invention is not particularly limited as long as it has an organopolysiloxane structure, but the use of a silicone resin cured by heating is advantageous in terms of mechanical strength and magnetic permeability. Is good.
Preferably, those having the structure represented by the above formula (1) are preferable, and among them, those in which R in the formula (1) contains a methyl group or a phenyl group are preferable. As the molecular weight of the silicone resin (a) represented by the formula (1), it is preferable to use a resin polymerized to a number average molecular weight of 300 or more in terms of polystyrene standard as measured by GPC (gel permeation chromatography). From the viewpoint of workability, it is more preferable to use a solid silicone resin whose softening temperature is adjusted to 30 ° C. or higher. If the softening point is 30 ° C. or lower, stickiness may occur after the treatment of the component (b) described below, which may lead to deterioration in workability. These silicone resins (a) are preferably contained in an amount of 30 to 100% by weight of the total resin. When it is necessary to heat-treat the silicone resin composition at a high temperature when obtaining the resin-bonded metal molded part of the present invention, 50 to 100% by weight of the total resin,
More preferably, it is desirable to contain 70 to 100% by weight of the silicone resin (a).

In the present invention, a resin other than the silicone resin (a) can be used to the extent that the magnetic permeability characteristics are not impaired. As other resins, for example, phenolic resin, urethane resin, epoxy resin, silicone resin,
Examples include, but are not limited to, polyester resins, urea resins, phenoxy resins, isocyanate resins, acrylic resins, thermosetting polyimide resins, and other thermoplastic resins.

As the metal or metal compound powder (b), those containing a metal or metal compound having magnetism for use as a magnetic component after compacting are preferable, but other than these, for example, aluminum powder, copper powder, Ni powder, A
Non-magnetic materials such as various alloys such as l-Ni powder may be contained. Specific examples of the magnetic metal or metal compound that can be used include atomized iron powder, reduced iron powder, permalloy (Ni-Fe alloy), silicon steel and silicon iron (Fe-
Si), sendust (Fe-Si-Al alloy), alpalm (Fe-Al alloy) and the like containing an iron component. Other examples include powders of metals or metal compounds having various magnetisms, such as alnico alloy powder, rare earth metal powder, and metal oxide powder. Of these components (b), powders containing an iron component are preferred.

The powder of the metal or metal compound used (b)
The average particle size of is not particularly limited.
Although it is necessary to select an optimal particle size in consideration of the magnetic permeability characteristics and the like, it is generally preferable to use a particle size of 2 mm or less, preferably 1 mm or less, more preferably 500 μm or less.

The silane coupling agent (c) is not particularly limited, but specific examples include 3-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, Chloropropylmethyldimethoxysilane, 3
3-glycidoxypropyltrimethoxysilane having at least one functional group or structure selected from the group consisting of chloropropyltrimethoxysilane and an epoxy group, an amino group, a ketimine structure and an imidazole structure in the molecule;
Glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl)
3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N- (2- (vinylbenzylamino) ethyl) 3-aminopropyltrimethoxysilane hydrochloride, N- (1,3 dimethylbutylidene) -3 −
Examples of (triethoxysilyl) -1-propanamine and imidazole type silane coupling agents include, for example, 2
Reaction product of methylimidazole and 3-glycidoxypropyltrimethoxysilane, reaction product of 2-ethyl-4-methylimidazole and 3-glycidoxypropyltrimethoxysilane, 2-ethyl-4-methylimidazole and 3-methacryloxypropyltrimethoxy A reaction product with silane is exemplified. These silane coupling agents can be used alone or in combination of two or more. Among them, it is particularly preferable to use a silane coupling agent having an amino group, a ketimine group, an imidazole group or the like which can be a reaction accelerator when heating the silicone resin (a). It is also possible to use a silane coupling agent having reactivity with them.

In the present invention, these silane coupling agents can be used in combination with other coupling agents as long as the magnetic permeability characteristics are not adversely affected. Other coupling agents include zirconium-based coupling agents, aluminum-based coupling agents, titanate-based coupling agents, and the like. Specific examples of the coupling agent that can be used include isopropyl (N-ethylaminoethylamino)
Titanate, isopropyl triisostearoyl titanate, titanium di (dioctyl pyrophosphate) oxyacetate, tetraisopropyl di (dioctyl phosphite) titanate, neoalkoxy tri (p-N- (β-aminoethyl) aminophenyl)
Titanium coupling agents such as titanate, Zr-acetylacetonate, Zr-methacrylate, Zr-propionate, neoalkoxy zirconate, neoalkoxytris neodecanoyl zirconate, neoalkoxytris (dodecanoyl) benzenesulfonyl zirconate, neoalkoxy Tris (ethylenediaminoethyl) zirconate, neoalkoxytris (m-aminophenyl) zirconate, ammonium zirconium carbonate, Al-acetylacetonate, A
Examples include zirconium such as l-methacrylate and Al-propionate, or an aluminum-based coupling agent.

When a silane coupling agent is used in combination with another coupling agent, the amount of the silane coupling agent is usually at least 30% by weight, preferably at least 50% by weight, more preferably at least 80% by weight of all the coupling agents. It is preferable to use the above proportion.

A coloring agent, a leveling agent, a lubricant and the like can be added to the silicone resin composition of the present invention according to the purpose. There is no particular limitation on the coloring agent, and various organic systems such as phthalocyanine, azo dyes, disazo dyes, quinacridone, anthraquinone, flavanthrone, perinone, perylene, dioxazine, condensed azo dyes, azomethine dyes, and methine dyes can be used. Pigments, and inorganic pigments include titanium oxide, lead sulfate, zinc oxide, chrome yellow, zinc yellow, chrome vermillion, red iron oxide, cobalt purple, navy blue, ultramarine, carbon black, chrome green, chromium oxide, cobalt green, and the like. .

Examples of the leveling agent include acrylates such as ethyl acrylate, butyl acrylate and 2-ethylhexyl acrylate having a molecular weight of 4000.
~ 12000 oligomers, epoxidized soy fatty acids,
Epoxidized aviethyl alcohol, hydrogenated castor oil, and the like. Examples of the lubricant include hydrocarbon lubricants such as paraffin wax, micro wax, and polyethylene wax, higher fatty acid lubricants such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and behenic acid, stearylamide, palmitylamide, Higher fatty acid amide lubricants such as oleylamide, methylenebisstearamide, ethylenebisstearamide, hydrogenated castor oil, butyl stearate, ethylene glycol monostearate, pentaerythritol (mono-, di-, tri-, or tetra-) ) Higher fatty acid ester lubricants such as stearate, cetyl alcohol, stearyl alcohol,
Alcohol-based lubricants such as polyethylene glycol and polyglycerol, and metals such as magnesium, calcium, cadmium, barium, zinc, and lead such as lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, ricinoleic acid, and naphthenic acid Examples include natural waxes such as salt metal soaps, carnauba wax, candelilla wax, beeswax and montan wax.

In order to obtain the resin-bonded metal molded part of the present invention, the above-mentioned components are mixed at a predetermined ratio by an arbitrary method and a resin-coated metal or metal compound powder (the silicone resin composition of the present invention) If necessary, pulverization may be carried out to make the particle size uniform), and thereafter, compacting and heat curing are performed.
Furthermore, when sintering is required after curing, heat treatment may be performed usually at 400 ° C. or higher for several hours. As the blending ratio of each of the above components, a metal or metal compound powder (b) in the entire composition
It is preferable to mix other components so that the content of the metal is usually 50% by weight or more. When a high magnetic permeability product is obtained, the powder (b) of the metal or metal compound is 90% by weight or more, and more preferably 98% by weight. It is better to contain the above. The usage ratio of the silicone resin (a) to the silane coupling material (c) is not particularly limited, but is usually 99: 1 to 3 by weight in consideration of the mechanical strength and heat resistance of the metal molded product.
0:70, preferably 98: 2 to 80:20, particularly preferably 95: 5 to 90:10. As a mixing method,
A method of dissolving the above-mentioned resins (which may be premixed with a kneader or the like) in an appropriate solvent in advance, uniformly mixing the solution with a powder of a metal or a metal compound, and then removing the solvent to obtain a powder. Or dry mixing of raw materials (including metal powders) using a Henschel mixer or the like, and then melting and heating and melting and mixing using a machine such as a kneader, extruder, batch kneader, and reaction kettle that can be heated and melted and kneaded. There is a method in which a powder is obtained by subjecting the mixture to cooling and solidification, pulverizing, and then collecting powder having a desired particle size. The method of mixing the resin and the powder of the metal or metal compound is not limited to these, and it is necessary to perform the method under appropriate methods and conditions so as not to impair the magnetic permeability characteristics. In the above, as the solvent,
There is no particular limitation as long as each component can be dissolved. Examples of ketone solvents include methyl ethyl ketone, methyl isobutyl ketone, acetone, and the like, and other organic solvents such as toluene, xylene, mesitylene, and dimethylformamide.

[0015]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the following examples, "parts" means parts by weight.

Example 1 100 parts of a silicone resin (A1) in which all Rs in the formula (1) are methyl groups, and 5 parts of 3-glycidoxypropylmethyldimethoxysilane are uniformly dissolved in 395 parts of methyl ethyl ketone, and the concentration is 20% by weight. % Resin solution was prepared. Using this resin liquid, the resin component in the total solid content was 1.0% by weight.
And then uniformly mixed with the reduced iron powder so as to obtain a powdered silicone resin composition of the present invention. The obtained silicone resin composition is put into a ring molding die and compacted to form an outer diameter of 20.
A metal molded product having a diameter of 10 mm, an inner diameter of 10 mm and a thickness of 7 mm was obtained. Next, this metal molded product was preheated and cured at 150 ° C. for 1 hour, and further baked at 470 ° C. for 4 hours to obtain a resin-bonded metal molded component of the present invention. The magnetic permeability of the obtained resin-bonded metal molded part was measured. Permeability measurement is 1
K, 1M, and 10 MHz, and the permeability value of 1 KHz is set as an initial value. A sample having a permeability value of 50% or more at 1 M and 10 MHz is ○, and a material having a permeability value of less than 50%. Table 2 shows the results of the frequency dependence as x.

Example 2 100 parts of a silicone resin (A2) wherein R in the formula (1) is all phenyl groups, N- (1,3 dimethylbutylidene)
-3- (Triethoxysilyl) -1-propanamine 5
Was uniformly dissolved in 395 parts of methyl ethyl ketone to prepare a resin solution having a concentration of 20% by weight. Using this resin liquid,
After mixing with the reduced iron powder and uniformly mixing so that the resin component in the total solid content accounts for 1.0% by weight, the solvent was naturally dried to obtain a powdery silicone resin composition of the present invention. . The obtained silicone resin composition is put into a mold for ring molding, and is subjected to green compaction, and has an outer diameter of 20 mm and an inner diameter of 10 mm.
A metal molded product having a thickness of 7 mm and a thickness of 7 mm was obtained. Next, this metal molded product was preheated and cured at 150 ° C. for 1 hour, and further baked at 470 ° C. for 4 hours to obtain a resin-bonded metal molded part of the present invention. The magnetic permeability of the obtained resin-bonded metal molded part was measured in the same manner as in Example 1. Table 2 shows the measurement results as frequency dependence. Comparative Example 1 A resin-bonded metal molding for comparison was obtained in the same manner as in Example 1 except that the components shown in Table 1 were used. The magnetic permeability of the obtained resin-bonded metal molded part was measured in the same manner as in Example 1. Table 2 shows the measurement results as frequency dependence. The numerical values in the composition column in Table 1 represent "parts".

Table 1 / Composition Table of Composition Example-1-2 Comparative Example Silicone Resin (A1) 100-100 Silicone Resin (A2) -100 Coupling Agent (C1) 5--Coupling Agent (C2) -5- MEK 395 395 400

[0019]

The abbreviations of the raw materials shown in Table 1 are as follows. Silicone resin (A1): a silicone resin in which R in formula (1) is all represented by a methyl group Silicone resin (A2): a silicone resin in which R in formula (1) is all represented by a phenyl group Coupling agent ( C1): 3-glycidoxypropyltrimethoxysilane coupling agent (C2): N- (1,3 dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine MEK: methyl ethyl ketone

[0021]

The silicone resin composition of the present invention can provide a resin-bonded metal molded part having excellent magnetic permeability frequency characteristics. Therefore, the resin-bonded metal molded part of the present invention is used for a toroidal core for noise prevention, a choke coil, a deflection yoke for an electron beam, a magnetic core of a transformer or a high-frequency part, a magnetic head, etc., furthermore, a home appliance or an automobile. It is very useful as a bonded magnet for motors.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F071 AA67 AB06 AB09 AB12 AC16 AE14 AE19 AF36 AH12 BA01 BB01 BC07 4J002 CP051 DA066 DA086 DA096 DC006 EX067 EX077 EX087 FD090 FD170 FD200 FD206 FD207 5E041 AA01 AA11B

Claims (5)

[Claims] 1. A silicone resin composition comprising a silicone resin (a), a metal or metal compound powder (b), and a silane coupling agent (c). 2. The silicone resin according to the following formula (1): ## STR1 ## (In the formula, n represents an integer of 10 to 30. Further, R is
It represents any one of a hydrogen atom, a methyl group, an ethyl group, a t-butyl group and a phenyl group, and may be the same or different. The silicone resin composition according to claim 1, which is represented by the formula: 3. The metal or metal compound powder (b) is a powder containing a metal or metal compound exhibiting magnetism.
Or the silicone resin composition according to 2. 4. The silicone resin composition according to claim 3, wherein the metal or metal compound exhibiting magnetism contains at least an iron component. 5. A resin-bonded metal molded part using the silicone resin composition according to any one of claims 1 to 4.