JPH08138923A - Composition for resin-bonded magnet and resin-bonded magnet - Google Patents

Abstract

(57) [Summary] [Structure] (A) Contains resin-coated magnetic powder obtained by coating the surface of a magnetic powder having an anisotropic magnetic field (H _A ) of 50 kOe or more with a thermosetting resin, and (B) a thermoplastic resin. A composition for a resin-bonded magnet. According to the present invention, it is possible to obtain a resin-bonded magnet having excellent magnetic properties, moldability, and mechanical strength.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composition capable of obtaining a resin-bonded magnet having excellent magnetic properties, moldability and mechanical strength.

[0002]

2. Description of the Related Art Ferrite magnets, alnico magnets, rare earth magnets, resin-bonded magnets, etc. are used in various applications including motors. Among them, the resin-bonded magnet is generally obtained by molding a composition in which a binder such as a thermoplastic resin is mixed with magnetic powder. However, in the resin-bonded magnet, when the compounding ratio of the magnetic powder becomes 80 wt% or more,
Since the viscosity at the time of melt molding rapidly increases, molding of the composition becomes difficult. In addition, since the composition contains a lubricant for thermoplastic resins such as stearic acid-based metal soap and paraffins, it has a drawback that mechanical strength is lowered. In particular, magnets used in small motors, audio equipment, office automation equipment, etc. are required to have excellent magnetic characteristics, moldability, and physical characteristics (mechanical strength, etc.) because of the demand for downsizing of the equipment. However, conventional resin-bonded magnets are not sufficient in all of them.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a composition capable of obtaining a resin-bonded magnet having good moldability, magnetic properties and mechanical strength.

[0004]

Means for Solving the Problems The first aspect of the present invention is (A)
_A resin-bonded magnet composition containing (B) a thermoplastic resin and a resin-coated magnetic powder obtained by coating the surface of a magnetic powder having an anisotropic magnetic field (H _A ) of 50 kOe or more with a thermosetting resin.
The second aspect of the present invention is that (A) the anisotropic magnetic field (H _A ) is 50 kO.
e Resin-coated magnetic powder obtained by coating the surface of magnetic powder of e or more with a thermosetting resin, (B) polyamide resin, and (C) at least one modification selected from the group consisting of epoxy groups, amino groups and carboxyl groups Modified silicone oil having a group 0.01 per 100 parts by weight of the polyamide resin
It is a composition for resin-bonded magnets containing about 50 parts by weight. The third aspect of the present invention is that (A) the anisotropic magnetic field (H _A ) is 50.
Resin-coated magnetic powder obtained by coating the surface of a magnetic powder of kOe or more with a thermosetting resin, (B) a polyamide resin, and (C) an epoxy group-containing aliphatic compound having 8 or more carbon atoms, relative to 100 parts by weight of the polyamide resin. It is a resin-bonded magnet composition containing 0.01 to 50 parts by weight.

The present invention will be described in detail below. (First composition of the present invention) (A) used in the components of the resin-coated magnetic powder present invention component (A) of the resin-coated magnetic powder, anisotropy field (H _A) the surface of the above magnetic powder 50kOe Is coated with a thermosetting resin. The magnetic powder used for the resin-coated magnetic powder has an anisotropic magnetic field (H _A ) of 50 kOe
With the above magnetic powder, the magnetic powder usually used for resin-bonded magnets can be used without particular limitation. For example, SmCo ₅ system, Sm ₂ (Co, Fe, Zr, V)
₁₇ series, Sm ₂ (Co, Cu, Fe, Zr) ₁₇ series, Sm ₂
(Co, Cu, Fe, Zr, Te) ₁₇ system, Sm ₂ (C
o, Cu, Fe, Ta, Te) ₁₇ series rare earth-cobalt system, for example, Nd-Fe-Co-B system, Nd-Dy-
Fe-B type, Nd-Fe-B type rare earth-iron-boron type, for example, Sm-Fe-N type, Nd-Fe-Ti-N type.
Examples thereof include rare earth-iron-nitrogen-based magnetic powders such as Nd-Fe-VN system. The particle size of the magnetic powder is preferably 200 μm or less on average, and particularly preferably 100 μm on average.
m or less.

The thermosetting resin is not particularly limited, and examples thereof include phenol resin, urea resin, melamine resin, xylene resin, diallyl phthalate resin,
Unsaturated polyester resin, phthalic acid resin, epoxy resin, furan resin, aniline resin, polyurethane resin, butone resin, polydiphenyl ether resin, alkylbenzene resin, benzoguanamine resin, polyamideimide resin, alkylbenzene resin, bismaleimide triazine resin, imide silicone resin , Polyimide resin and the like, and these can be used alone or in combination of two or more kinds. Further, together with these resins, if necessary, a curing agent, a curing accelerator, a modifier,
Stabilizers, diluents and the like can be used. The thickness of the thermosetting resin coating the surface of the magnetic powder is usually 0.1 to 5
It is 0 μm, preferably 1 to 10 μm. The method of coating the surface of the magnetic powder with the thermosetting resin is not particularly limited, but the following method can be given, for example.

The magnetic powder is mixed with necessary components such as a curable resin diluted with a solvent. Examples of the solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, N
-Methylpyrrolidone, toluene, xylene, hexane,
Examples thereof include organic solvents such as dimethylformamide, dimethylacetamide, triethylenetetramine and methylcellosolve. The blending amount of the thermosetting resin is preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the magnetic powder,
More preferably, it is 1 to 3 parts by weight. With such a blending amount, the coating thickness of the thermosetting resin can be set within the above range, and as a result, a magnet excellent in mechanical strength and magnetic characteristics can be obtained. Next, the mixture of the magnetic powder and the thermosetting resin or the like is dried in a vacuum dryer by sufficiently volatilizing the solvent, and then the thermosetting resin is cured.
The curing conditions cannot be unconditionally determined depending on the thermosetting resin used, but are usually 150 to 200 ° C. and 0.5
It is preferred to heat for ~ 2 hours. Then, after crushing this, the particle size distribution is adjusted with a sieve to obtain the resin-coated magnetic powder of the component (A). The content of the component (A) in the composition of the present invention is preferably 80 to 95% by weight.

Component (B) Thermoplastic Resin The component (B) thermoplastic resin used in the present invention is not particularly limited and includes, for example, 6 nylon, 6,6 nylon, 11 nylon, 12 Nylon,
Polyamide resins such as 6,12 nylon and aromatic nylon; low density, high density, high molecular weight polyethylene resins; polystyrene resins; polypropylene resins; polyphenylene sulfide resins; polyester resins such as polybutylene terephthalate resins and polyethylene terephthalate resins Copolymer resins such as acrylonitrile / butadiene / styrene copolymer resins, acrylonitrile / styrene copolymer resins, ethylene / vinyl acetate copolymer resins;
Polycarbonate resin; Polyether ether ketone resin; Polyvinyl acetal resin; Polyvinyl alcohol resin; Methyl methacrylate resin; Polyacetal resin;
Fluororesin such as polytetrafluoroethylene resin and polytrifluoroethylene chloride resin; polyphenylene oxide resin;
Examples thereof include trimethylpentene resin. Further, these homopolymers, copolymers with other kinds of monomers, or those obtained by treating these terminal groups may be used. These thermoplastic resins can be used alone or in combination of two or more kinds. The melt viscosity and molecular weight of these thermoplastic resins are preferably as low as possible in the range where desired mechanical strength is obtained. Specifically, the molecular weight is preferably 35,
000 or more, more preferably 10,000 to 25,
The range is 000.

The shape of the thermoplastic resin as the component (B) may be any of powder, beads, pellets and the like, and is not particularly limited, but in consideration of the uniform mixing property with the magnetic powder, it is powdery. Those are preferable. The blending amount of the thermoplastic resin as the component (B) is the same as that of the resin-coated magnetic powder 1 as the component (A).
4 to 50 parts by weight, preferably 5 to 100 parts by weight
10 parts by weight. If the blending amount is too small, the kneading torque and fluidity of the composition may be lowered to make molding difficult, and if the blending amount is too small, desired magnetic properties may not be obtained.

Other Components In addition to the above-mentioned components (A) and (B), a coupling agent, a plastic molding lubricant, various stabilizers, etc. may be added to the composition of the present invention, if necessary. it can. Examples of the coupling agent include silane-based, titanium-based,
Aluminum surface treatment agents may be mentioned, and specific examples thereof include vinyltriethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, and N-. −
Silane coupling agents such as (β-aminoethyl) -γ-aminopropylmethyldimethoxysilane and γ-mercaptopropyltrimethoxysilane; for example, isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, isopropyl tri ( Titanium-based coupling agents such as N-aminoethyl-aminoethyl) titanate, tetraoctylbis (ditridecyl phosphite) titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tridecylbenzene sulfonyl titanate; Examples thereof include aluminum-based coupling agents such as acetoalkoxyaluminum diisopropylate.

The amount of the coupling agent added is 0.1 to 3 parts by weight per 100 parts by weight of the resin-coated magnetic powder of the component (A).
0 weight part is preferable, More preferably, it is 0.5-1.
0 parts by weight. If the blending amount is too small, the molding processability is lowered, and as a result, the content of the magnetic powder cannot be increased, so it may not be possible to obtain a magnet with high magnetic properties. There is a case that the target strength cannot be obtained. The coupling agent may be mixed at the same time when the resin-coated magnetic powder of the component (A) and the thermoplastic resin of the component (B) are mixed, but the thermoplastic resin and the coupling agent may be mixed in advance. After carrying out various reactions, the resin-coated magnetic powder may be mixed therein.

Examples of the lubricant include waxes such as paraffin wax, liquid paraffin, polyethylene wax, polypropylene wax, ester wax, carnauba wax, and microwax; for example, stearic acid, 1,2-oxystearic acid, laurin. Fatty acids such as acids, palmitic acid, oleic acid;
Calcium stearate, barium stearate, magnesium stearate, lithium stearate, zinc stearate, aluminum stearate, calcium laurate, zinc linoleate, calcium ricinoleate,
Fatty acid salts (metal soaps) such as zinc 2-ethylhexoate; for example, stearic acid amide, oleic acid amide, erucic acid amide, behenic acid amide, palmitic acid amide, lauric acid amide, hydroxystearic acid amide, methylenebisstearic acid Fatty acid amides such as amide, ethylene bisstearic acid amide, ethylene bislauric acid amide, distearyl adipic acid amide, ethylene bisoleic acid amide, dioleyl adipic acid amide, N-stearyl stearic acid amide; Fatty acid esters of alcohols such as ethylene glycol and stearyl alcohol;
For example, polyethers such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and modified compounds thereof; for example, polysiloxanes such as dimethylpolysiloxane and silicon grease; for example, fluorine-based oil, fluorine-based grease, and the like. Fluorine compounds such as fluorine resin powder; for example, silicon nitride, silicon carbide,
Inorganic compound powders such as magnesium oxide, alumina, silicon dioxide and molybdenum disulfide are exemplified. The content of the lubricant is usually 0.1 to 20 parts by weight based on 100 parts by weight of the resin-coated magnetic powder of the component (A).

Examples of the stabilizer include bis (2,2
2,6,6-Tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6, -pentamethyl-4-)
Piperidyl) sebacate, 1- [2- {3- (3,5-
Di-tert-butyl-4-hydroxyphenyl) propionyloxy} ethyl] -4- {3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy}
-2,2,6,6-tetramethylpiperidine, 8-benzyl-7,7,9,9-tetramethyl-3-octyl-
1,2,3-Triazaspiro [4,5] undecane-
2,4-dione, 4-benzoyloxy-2,2,6
6-tetramethylpiperidine, dimethyl succinate-1-
(2-hydroxyethyl) -4-hydroxy-2,2
6,6-Tetramethylpiperidine polycondensate, poly [[6
-(1,1,3,3-tetramethylbutyl) imino-
1,3,5-triazine-2,4-diyl] [(2,
2,6,6-Tetramethyl-4-piperidyl) imino]
Hexamethylene [[2,2,6,6-tetramethyl-4
-Piperidyl) imino]], 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl ) And other hindered amine stabilizers, as well as phenolic, phosphite, thioether and other antioxidants. The amount of the stabilizer added is usually 0.0 with respect to 100 parts by weight of the resin-coated magnetic powder of the component (A).
It is 1 to 1 part by weight.

Preparation of Composition The composition of the present invention is obtained by mixing the above-mentioned components (A) and (B) and the above-mentioned other components which are added as necessary. The mixing method is not particularly limited, and for example, a mixer such as a ribbon blender, a tumbler, a Nauter mixer, a Henschel mixer, or a super mixer is used. Further, the mixture can be heat kneaded by using a kneader such as a Banbury mixer, a kneader, a roll, a kneader ruder, a single screw extruder or a twin screw extruder. The composition of the present invention can be obtained in the form of powder, beads, pellets, or a mixture thereof, but pellets are preferable from the viewpoint of easy handling. The resin-bonded magnet is manufactured by molding the composition of the present invention using various thermoplastic resin molding machines. An injection molding machine and an extrusion molding machine are preferably used as the thermoplastic resin molding machine.

[0015] (second composition of the present invention) (A) used in the components of the resin-coated magnetic powder present invention component (A) of the resin-coated magnetic powder, anisotropy field (H _A) is not less than 50kOe magnetic The surface of the powder is coated with a thermosetting resin, and the same resin-coated magnetic powder as the component (A) of the first composition of the present invention can be used. Component (B) Polyamide Resin As the component (B) polyamide resin used in the present invention,
There is no particular limitation, and for example, nylon 6, nylon 66, nylon 11, nylon 12, nylon 61
2, aromatic nylon and the like, and these 2
It is also possible to use copolymers of one or more kinds, and those whose end groups are treated with other compounds such as fatty acids such as stearic acid, palmitic acid, and linoleic acid, and linear or branched alkyl groups.

The polyamide resin used in the present invention preferably has a low melt viscosity and a low molecular weight as long as a desired mechanical strength can be obtained. Specifically, the molecular weight is preferably 35,
000 or less, more preferably 10,000 to 25,000
It is in the range of 0. The shape of the polyamide resin may be any shape such as powder shape, bead shape and pellet shape, and is not particularly limited, but in consideration of the uniform mixing property with the magnetic powder, the powder shape is preferable. Polyamide resin is
They can be used alone or in combination of two or more. The blending amount of the thermoplastic resin as the component (B) is 4 to 100 parts by weight of the resin-coated magnetic powder as the component (A).
It is 50 parts by weight, preferably 5 to 10 parts by weight. If the blending amount is too small, the kneading torque and fluidity of the composition may be lowered to make molding difficult, and if the blending amount is too small, desired magnetic properties may not be obtained.

[0017] (C) used in the modified silicone oil present invention component (C) component of the modified silicone oil,
It is a modified silicone oil having at least one modifying group selected from the group consisting of an epoxy group, an amino group and a carboxyl group. The epoxy group, amino group or carboxyl group has, for example, 1 to 1 carbon atoms such as propylene group.
0 alkylene group; for example, -C ₃ alkyleneoxy group having 1 to 10 carbon atoms, H ₆ O-like; for _{example, -C 3 H 6 O (CH} 2 CH 2 O) a C 3 H 6 O- ( Here, a is an integer of 1 to 100.) Divalent polyether group; introduced into the silicon atom of the silicone oil through the divalent organic group. Further, the epoxy group, amino group or carboxyl group may be introduced into either the side chain or the terminal of the silicone oil, and may be introduced into both the side chain and the terminal of course. Also,
The viscosity of the modified silicone oil as the component (C) is not particularly limited, but usually 10 cSt to 10,000 cSt (2
5 ° C.) range. The molecular weight is about 100
It is in the range of 0 to 500,000. Examples of the modified silicone oil as the component (C) include, for example, the following general formula (1)
:

[0018]

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[Wherein R ¹ is, for example,

[0020]

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An epoxy group-containing organic group such as (m is an integer of 1 or more); for example,-(CH ₂ ) _m NH ₂ ,-(CH ₂ ) _x --NH-(C
H ₂ ) _y —NH ₂ (m, x, y is an integer of 1 or more) and other amino group-containing organic groups; for example, — (CH ₂ ) _x COOH, — (CH ₂ )
_{x -CH (COOH) 2, -} (CH 2) x -CH (CO
_{OH) - (CH 2) y} -COOH, (x, y represents an integer of 1 or more) carboxyl-containing organic group such as, they may be the same or different when R ¹ there are a plurality. R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms such as a methyl group and an ethyl group;
For example, an aryl group such as a phenyl group; a monovalent organic group, and when a plurality of R ^2's are present, they may be the same or different. m is an integer of 0 to 3, and n is an integer of 0 to 3. s, t and u are s ≧ 0, t ≧ 0, u ≧ 0,
It is an integer that satisfies 1 ≦ s + t + u ≦ 7,000. However, m, n, t, and u do not become 0 at the same time. ] The compound represented by these is mentioned.

Specifically, dimethyl silicone oil,
Epoxy on the terminal and / or side chain of diethyl silicone oil, methyl ethyl silicone oil, methyl phenyl silicone oil, ethyl phenyl silicone oil, diphenyl silicone oil, methyl hydrogen silicone oil, ethyl hydrogen silicone oil, phenyl hydrogen silicone oil, etc. Examples thereof include those into which at least one kind of group selected from the group consisting of a group, an amino group and a carboxyl group is introduced, but not limited thereto.

The modified silicone oil as the component (C) can be used alone or in combination of two or more kinds. The blending amount of the component (C) is 0.01 to 50 parts by weight, preferably 0.1 to 20 parts by weight, more preferably 1 to 100 parts by weight with respect to 100 parts by weight of the polyamide resin of the component (B). 10 parts by weight. The blending amount of component (C) is
When the amount is less than 0.01 parts by weight based on 100 parts by weight of the component (B), moldability is deteriorated, and as a result, the content of the magnetic powder cannot be increased, so that a magnet having high magnetic properties can be obtained. Can not. In addition, the blending amount of the component (C) is
When the amount is more than 50 parts by weight based on 100 parts by weight of the component (B), desired physical properties (especially mechanical strength and magnetic properties) are obtained.
Can't get The component (C) may be mixed with the resin-coated magnetic powder of the component (A) and the polyamide resin of the component (B) at the same time, or may be mixed with the polyamide resin of the component (B) in advance.

Other Components In addition to the components (A), (B) and (C), the composition of the present invention may further contain a coupling agent, a plastic molding lubricant, various stabilizers, etc., if necessary. It can be blended.
As the coupling agent, the plastic molding lubricant, and the stabilizer, the same ones as those used in the first composition of the present invention can be used. The amount of the coupling agent blended is preferably 0.1 to 3.0 parts by weight, more preferably 0.5 to 1 part by weight, based on 100 parts by weight of the resin-coated magnetic powder of the component (A). . If the blending amount is too small, the molding processability is lowered, and as a result, the content of the magnetic powder cannot be increased, so it may not be possible to obtain a magnet with high magnetic properties. There is a case that the target strength cannot be obtained. The content of the lubricant is usually 0.1 to 20 parts by weight based on 100 parts by weight of the resin-coated magnetic powder of the component (A). The content of the stabilizer is usually 0.01 to 1 part by weight based on 100 parts by weight of the resin-coated magnetic powder of the component (A).

Preparation of Composition The composition of the present invention is obtained by mixing the above-mentioned components (A), (B), and (C), and the above-mentioned other components which are optionally added. . The mixing method is not particularly limited, and the same method as the method used for the first composition of the present invention can be used. The composition of the present invention can be obtained in the form of powder, beads, pellets, or a mixture thereof, but pellets are preferable from the viewpoint of easy handling. The resin-bonded magnet is manufactured by molding the composition of the present invention using various thermoplastic resin molding machines. An injection molding machine and an extrusion molding machine are preferably used as the thermoplastic resin molding machine.

[0026] (third composition of the present invention) (A) used in the components of the resin-coated magnetic powder present invention component (A) of the resin-coated magnetic powder, anisotropy field (H _A) is not less than 50kOe magnetic The surface of the powder is coated with a thermosetting resin, and the same resin-coated magnetic powder as the component (A) of the first composition of the present invention can be used.

Component (B) Polyamide Resin As the component (B) polyamide resin used in the present invention,
There is no particular limitation, and the same polyamide resin as the component (B) of the second composition of the present invention can be used. The blending amount of the thermoplastic resin as the component (B) is 4 to 50 parts by weight, preferably 5 to 10 parts by weight, relative to 100 parts by weight of the resin-coated magnetic powder as the component (A). If this blending amount is too small, the kneading torque of the composition,
The fluidity may be lowered to make molding difficult, and if it is too small, desired magnetic properties may not be obtained.

Component (C) Aliphatic Compound The component (C) aliphatic compound used in the present invention is a saturated or unsaturated aliphatic compound having 8 or more carbon atoms, preferably 8 to 20 carbon atoms. Specific examples of the aliphatic compound as the component (C) include linear saturated fats such as n-octyl glycidyl ether, n-undecyl glycidyl ether, n-tridecyl glycidyl ether, and n-octadecyl glycidyl ether. Group glycidyl ethers; for example, linear saturated aliphatic monoepoxys such as epoxy n-octane; branched saturated aliphatic glycidyl ethers such as 2-ethylhexyl glycidyl ether, 2-propyl undecyl glycidyl ether; , A linear unsaturated aliphatic glycidyl ether such as 2-octenyl glycidyl ether; a branched unsaturated aliphatic glycidyl ether such as 2-allyl octadecyl glycidyl ether; an alicyclic group such as cyclohexyl glycidyl ether Glycidyl ether ; For example, there may be mentioned alicyclic monoepoxy compounds such as epoxycyclooctane, they may be alone or in combination of two or more use.

The blending amount of the component (C) is 0.01 to 50 parts by weight, preferably 0.1 to 20 parts by weight, and more preferably 100 parts by weight of the polyamide resin as the component (B). Is 1 to 10 parts by weight. When the blending amount of the component (C) is less than 0.01 parts by weight with respect to 100 parts by weight of the component (B), moldability is deteriorated and, as a result, the magnetic powder content cannot be increased. It is not possible to obtain a magnet with high magnetic properties. Further, when the blending amount of the component (C) exceeds 50 parts by weight with respect to 100 parts by weight of the component (B), desired physical properties (particularly mechanical strength and magnetic properties) cannot be obtained. The component (C) may be mixed with the magnetic powder of the component (A) and the polyamide resin of the component (B) at the same time, or may be mixed in advance with the polyamide resin of the component (B).

Other Components In addition to the above-mentioned components (A), (B) and (C), the composition of the present invention may further contain a coupling agent, a plastic molding lubricant, various stabilizers, etc., if necessary. It can be blended.
As the coupling agent, the plastic molding lubricant, and the stabilizer, the same ones as those used in the first composition of the present invention can be used. The amount of the coupling agent blended is preferably 0.1 to 3.0 parts by weight, more preferably 0.5 to 1 part by weight, based on 100 parts by weight of the resin-coated magnetic powder of the component (A). . If the blending amount is too small, the molding processability is lowered, and as a result, the content of the magnetic powder cannot be increased, so it may not be possible to obtain a magnet with high magnetic properties. There is a case that the target strength cannot be obtained. The content of the lubricant is usually 0.1 to 20 parts by weight based on 100 parts by weight of the resin-coated magnetic powder of the component (A). The content of the stabilizer is usually 0.01 to 1 part by weight based on 100 parts by weight of the resin-coated magnetic powder of the component (A).

Preparation of Composition The composition of the present invention is obtained by mixing the above-mentioned components (A), (B), and (C), and the above-mentioned other components which are optionally added. . The mixing method is not particularly limited, and the same method as the method used for the first composition of the present invention can be used. The composition of the present invention can be obtained in the form of powder, beads, pellets, or a mixture thereof, but pellets are preferable from the viewpoint of easy handling. The resin-bonded magnet is manufactured by molding the composition of the present invention using various thermoplastic resin molding machines. An injection molding machine and an extrusion molding machine are preferably used as the thermoplastic resin molding machine.

[0032]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited to the following examples. (Examples I-1 to 12, Comparative Examples I-1 to 4) Resin coating of material (A) component Magnetic powder Magnetic powder Magnetic powder SmCo ₅ type magnetic powder Anisotropic magnetic field: 246 kOe Product name: RCo ₅ alloy, Sumitomo Metal Mining Co., Ltd. Magnetic powder Nd-Fe-B system magnetic powder Anisotropic magnetic field: 70.4 kOe, Product name: MQP-B, US General Motors Co. thermosetting resin Curing resin Epoxy resin (Product name: Epotote YD-7011, 2 parts by weight of Toto Kasei Co., Ltd. and a curing agent (trade name: DICY)
7. Mixture with 0.2 part by weight of Yuka Shell Epoxy Co., Ltd. Curable resin Bismaleimide triazine resin (trade name: BT210
0, manufactured by Mitsubishi Gas Chemical Co., Inc.

Component (B) Thermoplastic resin Plastic resin Polyamide resin (trade name: UBE nylon, 3014
U, Ube Industries, Ltd.) Plastic resin Polyphenylene sulfide resin (trade name: Fortron W-110, Kureha Chemical Industry Co., Ltd.)

Preparation of Composition Magnetic powder or 100 parts by weight and thermosetting resin diluted with methyl ethyl ketone in the amounts (parts by weight) shown in Tables 1 to 4 were mixed with a planetary mixer, and taken out. It was dried at room temperature for 12 hours using a vacuum dryer.
Next, this was heated at 180 ° C. for 1 hour to cure the thermosetting resin, which was ground and then sieved to obtain a resin-coated magnetic powder of component (A). Next, with respect to 100 parts by weight of magnetic powder or (A) component equivalent to 100 parts by weight, (B) component in the amounts (parts by weight) shown in Tables 1 to 4, and 100 parts by weight of (B) component, lithium stearate 2. 0 parts by weight and a lubricant consisting of 2.0 parts by weight of dimethylpolysiloxane were mixed and stirred in a planetary mixer (40 rpm, 80 ° C.) and then -76.
It was dried in an oven at 0 mmHg and 120 ° C. for 24 hours. The obtained mixture was mixed with a 20 mmφ single extruder (L
/ D = 25, CR = 2.0, rotation speed = 20 rpm, 5 m
mφ strand die, cylinder temperature 200 ℃ ~ 280
C., die temperature: 280.degree. C.), and a pellet compound of 5 mm.phi..times.5 mm was prepared with a hot cut pelletizer. The obtained pellet compound was evaluated for fluidity by the following method. The results are shown in Tables 1 to 4.

Fluidity (MFR) Evaluation ASTM D1238-65T and ASTM D1430
The fluidity of the magnet obtained with reference to -58 etc. was measured at a temperature of 200 using a high-performance flow tester manufactured by Shimadzu Corporation.
° C, load: 30 kgf, die shape: 1 mmφ x 1 m
m, preheat: Measured under the condition of 120 seconds. 1.5g
If the fluidity is not less than 1 minute, there is no problem in molding processability. Preferably, it is 1.5 to 10 g / min. The pellet compound obtained in each of the examples and comparative examples was molded as follows to manufacture a magnet.

Molding The obtained pellet compound was molded using a magnetic field injection molding machine (trade name: J-20M, manufactured by Japan Steel Works, Ltd.) at a molding temperature of 240 to 350 ° C. and a mold temperature of 100 to 15.
Molding was performed at 0 ° C. to obtain a test resin-bonded magnet having a width of 5 mm, a length of 20 mm, and a thickness of 4 mm. Incidentally, only the pellet compound using the magnetic powder was molded in a mold in a magnetic field of 15 to 20 kOe. The mechanical strength and magnetic properties of the magnets obtained in the respective examples and comparative examples were evaluated by the following methods. The results are shown in Tables 1 to 4. Each evaluation method

Evaluation of mechanical strength (3-point bending strength) The bending strength of the magnet obtained with reference to ASTM D790-66 and the like was measured using an autograph manufactured by Shimadzu Corporation. The head speed was 2 mm / min, and the measurement was performed at room temperature. If the bending strength is 15.0 kgf / mm ² or more, the mechanical strength is sufficient. -Magnetic property evaluation The magnetic property of the obtained magnet was measured at room temperature with a Thiophie type magnetic flux meter. Tables 1 to 4 show the measurement results of (BH) max (maximum magnetic energy product) of the magnetic properties.

[0038]

[Table 1]

[0039]

[Table 2]

[0040]

[Table 3]

[0041]

[Table 4]

(Examples II-1 to 15 and Comparative examples II-1 to II-1)
3) Materials (A) component of the resin-coated magnetic powder magnetic powder and thermosetting resin used were the same as in Example I. (B) Component polyamide resin nylon 12 Product name: UBE nylon, 3014U, Ube Industries, Ltd. (C) Component modified silicone oil oil Side chain amino modified dimethyl silicone oil Product name: BY16-850; Viscosity 1,100 cSt ( (Toray Dow Corning Silicone Co., Ltd.)

[0043]

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Oil Side-chain glycidyl-modified dimethyl silicone oil Product name: SF8413; Viscosity 8,000 cSt (Toray Dow Corning Silicone Co., Ltd.)

[0045]

[Chemical 4]

Oil Carboxyl-modified dimethyl silicone oil on both ends Product name: SF8418; Viscosity 2,500 cSt (Toray Dow Corning Silicone Co., Ltd.)

[0047]

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Oil Unmodified straight dimethyl silicone oil Product name: SH200 oil; viscosity 10,000 cSt (Toray Dow Corning Silicone Co., Ltd.)

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[Chemical 6]

Preparation of Composition In the same manner as in Example I, a resin-coated magnetic powder of the component (A) was obtained. Next, magnetic powder or 100 parts by weight of (A)
Components, and the amount (parts by weight) of component (B) shown in Tables 1 to 4,
After mixing and stirring 2.0 parts by weight of lithium stearate with 100 parts by weight of component (B) as a lubricant in a planetary mixer (40 rpm, 80 ° C.), the mixture was -760 mm.
It was dried in an Hg, 120 ° C. oven for 24 hours. The obtained mixture was mixed with a 20 mmφ single extruder (L /
D = 25, CR = 2.0, rotation speed = 20 rpm, 5 mm
φstrand die, cylinder temperature 200 ℃ ～ 280
C., die temperature: 280.degree. C.), and a pellet compound of 5 mm.phi..times.5 mm was prepared with a hot cut pelletizer. The resulting pellet compound was evaluated for fluidity in the same manner as in Example I, and a magnet was produced in the same manner as in Example I. The obtained magnet was evaluated for mechanical strength and magnetic properties. went. The results are shown in Tables 5-8.

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[Table 5]

[0052]

[Table 6]

[0053]

[Table 7]

[0054]

[Table 8]

(Examples III-1 to 14 and Comparative Example III-1)
3) Resin-coated magnetic powder of material (A) Component The same magnetic powder and thermosetting resin as in Example II were used. Polyamide resin as component (B) The same polyamide resin as in Example II was used. Epoxy group-containing aliphatic compound as component (C) Octadecyl monoglycidyl ether Product name: YED-111, Yuka Shell Epoxy Co., Ltd. Compound 1,2-epoxycyclooctane Product number: 818699-1, Kanto Chemical Co., Ltd.

Preparation of Composition In the same manner as in Example II, a resin-coated magnetic powder of the component (A) was obtained, and a pellet compound was prepared. The resulting pellet compound was evaluated for fluidity in the same manner as in Example I, and a magnet was produced in the same manner as in Example I. The obtained magnet was evaluated for mechanical strength and magnetic properties. went. The results are shown in Tables 9-12.

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[Table 9]

[0058]

[Table 10]

[0059]

[Table 11]

[0060]

[Table 12]

[0061]

Industrial Applicability The resin-bonded magnet composition of the present invention provides a resin-bonded magnet having excellent moldability, excellent magnetic properties, and physical properties (especially mechanical strength). You can Therefore, applications requiring all formability, magnetic properties, and mechanical strength, such as general household appliances, communications,
It is useful in a wide range of fields such as audio equipment, medical equipment, and general industrial equipment. Further, in particular, the resin-bonded magnet composition of the present invention is suitable for injection molding or extrusion molding because the viscosity does not become too high and the fluidity is good even when the content ratio of the magnetic powder is 80% by weight or more. Therefore, it is possible to easily manufacture a magnet having a thin portion and a magnet having a complicated shape.

Claims (3)

[Claims] 1. (A) An anisotropic magnetic field (H _A ) of 50 kOe
A resin-bonded magnet composition containing the resin-coated magnetic powder obtained by coating the surface of the above magnetic powder with a thermosetting resin, and (B) a thermoplastic resin. 2. (A) An anisotropic magnetic field (H _A ) of 50 kOe
Resin-coated magnetic powder obtained by coating the surface of the above magnetic powder with a thermosetting resin, (B) polyamide resin, and (C) at least one modified group selected from the group consisting of epoxy groups, amino groups and carboxyl groups. Modified silicone oil having 0.01 to 100 parts by weight of the polyamide resin
A resin-bonded magnet composition containing 50 parts by weight. 3. (A) An anisotropic magnetic field (H _A ) of 50 kO
Resin-coated magnetic powder obtained by coating the surface of magnetic powder of e or more with a thermosetting resin, (B) polyamide resin, and (C) carbon number 8
The above epoxy group-containing aliphatic compound: A resin-bonded magnet composition containing 0.01 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin.