JP2003142309A - Composition for resin-bonded magnet, and resin-bonded magnet manufactured by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for resin-bonded magnet that has proper magnetic characteristics and degrees of freedom for shaped and is excellent in rust-preventing characteristic, moldability, mechanism strength, flexibility, heat resistance, etc., and to provide a resin-bonded magnet manufactured by using the composition. SOLUTION: The composition for resin-bonded magnet contains magnetic powder (A) and a resin binder (B), and the powder (A) is coated with an abietic acid-based compound (D1) and an aluminum-based coupling agent (D2), after the powder (A) is surface-treated with an inorganic phosphoric acid-based compound (C).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-bonded magnet composition and a resin-bonded magnet using the same, and more specifically, it has good magnetic properties, flexibility in shape, and rust resistance. , A resin-bonded magnet composition excellent in moldability, mechanical strength, flexibility, heat resistance and the like, and a resin-bonded magnet using the same.

[0002]

2. Description of the Related Art In recent years, ferrite magnets, alnico magnets,
Rare earth magnets are incorporated and used as motors in various products such as general home appliances, communication / audio equipment, medical equipment, and general industrial equipment. These magnets are mainly manufactured by a sintering method, but are difficult to form into a complicated shape because they are brittle and are hard to be thinned.
Since it shrinks by up to 20%, the dimensional accuracy cannot be improved, and post-processing such as polishing is required, which is a major limitation in terms of application.

On the other hand, resin-bonded magnets (also referred to as bonded magnets) can be easily manufactured by filling magnetic powder with a thermoplastic resin such as polyamide resin or polyphenylene sulfide resin as a binder, and thus have new applications. It is unfolding. However, since it is subjected to severe shearing in the manufacturing process, a new surface is likely to appear in the magnet powder, and it is said that the rare earth magnet material particularly containing iron element has extremely poor rust property under salt water.

Further, a resin-bonded magnet using a thermosetting resin such as an epoxy resin or a bis-maleimidetriazine resin as a resin binder has been proposed, but since the function of the binder is weak, it is extremely likely to rust even in a fresh water environment. ,
Moreover, since it is only a simple molded product obtained by compression molding and has low mechanical strength, coating of a molded body was indispensable for preventing powder falling and rust.

Under such circumstances, Japanese Patent Laid-Open No. 1-11180
In JP-A-1 No. 1, a method of coating the surface of a rare earth magnet with a monocarboxylic acid such as butyric acid or caproic acid or a reaction product of a monocarboxylic acid and a polyhydric alcohol to improve its oxidation resistance and storage stability. In addition, Japanese Patent Publication No. 4-22007 proposes a permanent magnet in which a resin layer is coated on an oxidation resistant chemical conversion coating obtained by treating the surface of a rare earth magnet with zinc phosphate or the like. Although these methods can be expected to improve rust prevention, none of them mentions application to resin-bonded magnets having a degree of freedom in shape.

[0006] In recent years, resin-bonded magnets for small motors, audio equipment, and OA equipment have become smaller as the equipment becomes smaller.
There is a strong demand for a composition for magnets that has excellent magnetic properties and a high degree of freedom in shape, but there is no conventional resin-bonded magnet that satisfies both of these conditions; moldability, mechanical strength, and flexibility. It has been earnestly desired to develop a rare earth-based resin-bonded magnet composition excellent in heat resistance and heat resistance.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the object of the present invention is to provide good magnetic properties, flexibility in shape, and rust resistance, formability, mechanical strength,
It is intended to provide a resin-bonded magnet composition having excellent flexibility and heat resistance, and a resin-bonded magnet using the composition.

[0008]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that in a resin-bonded magnet composition containing a magnetic powder (A) and a resin binder (B). When the magnetic powder (A) is surface-treated with the inorganic phosphoric acid compound (C) in advance, and then coated with the compounds (D1) and (D2) having a specific structure, the magnetic properties are good and the degree of freedom in shape is high. There is also rust resistance,
The inventors have found that a composition for resin-bonded magnets excellent in moldability, mechanical strength, flexibility and heat resistance can be obtained, and completed the present invention.

That is, according to the first aspect of the present invention, in the resin-bonded magnet composition containing the magnetic powder (A) and the resin binder (B), the magnetic powder (A) is an inorganic phosphate compound in advance. Provided is a composition for resin-bonded magnet, which is surface-treated with (C) and then further coated with an abietic acid compound (D1) and an aluminum coupling agent (D2).

According to the second aspect of the present invention, the first aspect
In the invention, there is provided a resin-bonded magnet composition, wherein the magnetic powder (A) has an anisotropic magnetic field (HA) of 50 kOe or more.

According to the third aspect of the present invention, the first aspect
In the invention, there is provided a resin-bonded magnet composition, wherein the magnetic powder (A) contains magnetic powder having a particle diameter of 100 μm or less in an amount of 30% by weight or more based on the total amount of the magnetic powder (A). .

According to a fourth aspect of the present invention, the first aspect
3 to 3, the magnetic powder (A) is rare earth-iron-
Provided is a composition for a resin-bonded magnet, which is nitrogen-based.

According to a fifth aspect of the present invention, the first aspect
In the invention, the abietic acid compound (D1) is at least one compound selected from abietic acid represented by the following general formula (1), isomers thereof, or derivatives thereof. A composition for a bonded magnet is provided. C ₁₉ H _n COOH (1) (In the formula, n is an integer of 25 or more and 33 or less.)

According to a sixth aspect of the present invention, the first aspect
In the invention, the aluminum-based coupling agent (C
There is provided a composition for resin-bonded magnet, wherein 2) is an alkoxyaluminum chelate.

According to a seventh aspect of the present invention, the first aspect
In the invention, the content of the inorganic phosphoric acid compound (C), the abietic acid compound (D1) or the aluminum coupling agent (D2) is 0.01 to 100 parts by weight with respect to 100 parts by weight of the magnetic powder (A). There is provided a resin-bonded magnet composition, which is 10 parts by weight.

On the other hand, according to the eighth aspect of the present invention, the first aspect
In the inventions No. 7 to 7, there are provided resin-bonded magnets obtained by molding the resin-bonded magnet composition by any molding method selected from an injection molding method, a compression molding method, an extrusion molding method, and a rolling molding method. It

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The resin-bonded magnet composition of the present invention and the resin-bonded magnet using the same will be described in detail below.

1. Magnetic Powder, Treatment / Coating Component Thereof, Resin Binder A Magnetic Powder Magnetic powder is not particularly limited, and various magnetic powders such as rare earth magnetic powder, ferrite, and alnico which are usually used as raw materials for resin-bonded magnets can be used.

These may be used alone or as a mixture (hybrid).
In addition to anisotropic magnetic powder, isotropic magnetic powder is also applicable, but anisotropic magnetic field (HA) is 5
A magnetic powder of 0 kOe or more, particularly 70 kOe or more is preferable. A magnetic powder containing magnet powder having a particle diameter of 100 μm or less in an amount of 30% by weight or more, particularly 50% by weight or more, based on the total amount of the magnetic powder (A) is preferable.

A rare earth-transition metal type, for example, a rare earth cobalt type, a rare earth-iron-boron type, a rare earth-iron-nitrogen type magnetic powder or the like can be used. Among them, a rare earth-iron-nitrogen type magnetic powder is preferable. is there. Sm, N as rare earth elements
Examples thereof include d, Pr, Y, La, Ce and Gd, which can be used alone or as a mixture. Among these, especially Sm or Nd is 4-40 at. %, Fe 50 to 90
at. % Content is preferable.

The ferrite type magnetic powder contains an alkaline earth metal such as strontium and barium and iron oxide, and is an M type ferrite magnet having a hexagonal ferriferromagnetic crystal as a main phase. Specific examples thereof include barium ferrite type (BaO.6Fe ₂ O ₃ ) and strontium ferrite type (SrO.6Fe ₂ O ₃ ). In addition to these, W type of SrZn ²⁺ ₂ Fe ₁₆ O ₂₇ Hexagonal ferrite can also be used. Among these, strontium ferrite magnetic powder is particularly preferable.

The rare earth-transition metal magnetic powder has a high anisotropic magnetic field and excellent magnetic performance, but is expensive. On the other hand, the ferrite-based magnetic powder is not as good as the rare earth-transition metal-based magnetic powder in magnetic performance, but has the advantage of being inexpensive and easily available. Therefore, it can be used as a hybrid magnetic powder obtained by mixing ferrite magnetic powder with rare earth-transition metal magnetic powder. A hybrid magnetic powder obtained by mixing 10 to 70 parts by weight, preferably 30 to 60 parts by weight of ferrite magnetic powder with 100 parts by weight of rare earth-transition metal magnetic powder is effective.

B Resin Binder The resin binder of the present invention is a component that acts as a binder for the magnetic powder, and is not limited to a thermoplastic resin or a thermosetting resin and its type. The shape of the resin is
Powder, beads, pellets, etc. are not particularly limited,
A powder that can be uniformly mixed with the magnetic powder is desirable.

As the thermoplastic resin, for example, 6 nylon, 66 nylon, 11 nylon, 12 nylon, 61
Polyamide resins such as 2 nylon, aromatic nylon, and modified nylon obtained by partially or copolymerizing these; linear polyphenylene sulfide resin, crosslinked polyphenylene sulfide resin, semi-crosslinked polyphenylene sulfide resin; low density polyethylene, Linear low density polyethylene resin, high density polyethylene resin, ultra high molecular weight polyethylene resin, polypropylene resin, ethylene / vinyl acetate copolymer resin, ethylene / ethyl acrylate copolymer resin, ionomer resin, polymethylpentene resin; polystyrene resin, acrylonitrile / Butadiene / styrene copolymer resin, acrylonitrile / styrene copolymer resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyvinyl butyral resin , Polyvinyl formal resin, methacrylic resin; polyvinylidene fluoride resin, polytrifluorochloroethylene resin, tetrafluoroethylene / hexafluoropropylene copolymer resin, ethylene / tetrafluoroethylene copolymer resin, tetrafluoroethylene / per Fluoroalkyl vinyl ether copolymer resin, polytetrafluoroethylene resin;
Polycarbonate resin, polyacetal resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyphenylene oxide resin, polyallyl ether allyl sulfone resin, polyether sulfone resin,
Examples thereof include polyether ether ketone resin, polyarylate resin, aromatic polyester resin, cellulose acetate resin, and elastomers of these resins.

These may be monomers, random copolymers with other kinds of monomers, block copolymers, graft copolymers, and modified end groups thereof. Among them, 12 nylon, its modified nylon, nylon elastomer or polyphenylene sulfide resin is preferable from the viewpoint of the characteristics of the obtained molded product and the ease of production. It is also possible to blend two or more of these thermoplastic resins.

The molecular weight of these thermoplastic resins is preferably as low as possible so long as the desired mechanical strength can be obtained. For example, in the case of 12 nylon, the average molecular weight is preferably 15,000 or less.

As the thermosetting resin binder, for example, phenol resin, amino resin such as urea resin and melamine resin, diallyl phthalate resin, epoxy resin, unsaturated polyester resin, vinyl ester resin,
Examples thereof include polyurethane resin, polyimide resin, bis-maleimide triazine resin, and silicone resin, and one or more of these may be used. Unsaturated polyester resin and vinyl ester resin are preferable.

Radical-reactive thermosetting resins such as unsaturated polyester resins which exhibit rapid curing reactivity at a relatively low temperature are preferable resins because resin-bonded magnets can be easily obtained by injection molding.

The unsaturated polyester resin is, for example, a resin having an average molecular weight of about 5,000 or less by preliminarily polymerizing an unsaturated polybasic acid and / or a saturated polybasic acid and a glycol to form an oligomer or a prepolymer. Can be prepared. The unsaturated polyester resin can be mixed with various reactive resins such as the above-mentioned various thermosetting resins such as novolac type or bisphenol type vinyl ester resins made of epoxy resin as a raw material.

The resin binder of the present invention is constituted by using these as the main ingredients, and mixing the monomers also serving as the crosslinking agent, the curing agent for initiating the reaction, and the polymerization inhibitor for ensuring the long-term storage stability.

The unsaturated polybasic acid is, for example, maleic anhydride, fumaric acid, itaconic acid, etc., and the saturated polybasic acid is phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, methyltetrahydro. Examples thereof include phthalic anhydride, endomethylenetetrahydrophthalic anhydride, adipic acid, sebacic acid, het acid, and tetrabromophthalic anhydride.

Examples of glycols include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1,3-butanediol, 1,6-hexanediol, hydrogenated bisphenol A and bisphenol A.
Propylene oxide adducts, dibromoneopentyl glycol, pentaerythritol diallyl ether, allyl glycidyl ether and the like can be mentioned.

Examples of the monomers also serving as a crosslinking agent include styrene, vinyltoluene, α-methylstyrene,
Vinyl monomers such as methyl methacrylate and vinyl acetate, allyl monomers such as diallyl phthalate, diallyl isophthalate, triallyl isophthalate, triallyl isocyanurate, diallyl tetrabrom phthalate, phenoxyethyl acrylate, 1,6-hexanediol Examples thereof include acrylic acid esters such as diacrylate, trimethylolpropane triacrylate, and 2-hydroxyethyl acrylate.

As the curing agent, an organic peroxide is generally used, such as methyl ethyl ketone peroxide,
Ketone peroxides such as cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, and acetylceton peroxide; 3,3,5-trimethylcyclohexane, 1,1- Bis (t-butylperoxy) cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl-4,4-bis (t-butylperoxy) valerate, 2,2-bis (t- Peroxyketals such as butylperoxy) butane; t-butyl hydroperoxide, cumene hydroperoxide,
Di-isopropylbenzene hydroperoxide, menthane hydroperoxide, 2,5-dimethylhexane 2,5-dihydroperoxide, 1,1,3
Hydroperoxides such as 3-tetramethylbutyl hydroperoxide; di-t-butyl peroxide, t-butylcumyl peroxide, di-cumyl peroxide, α, α′-bis (t-butylperoxy-)
Isopropyl) benzene, 2,5-dimethyl-2,5-
Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3
Dialkyl peroxides such as acetyl peroxide, isobutyl peroxide, octanonyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, succinic acid peroxide, benzoyl peroxide, Diacyl peroxides such as 2,4-dichlorobenzoyl peroxide and toluoyl peroxide; di-isopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, bis-
(4-t-butylcyclohexyl) peroxydicarbonate, di-myristyl peroxydicarbonate, di-2
Peroxydicarbonates such as ethoxyethyl peroxydicarbonate, di-methoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, diallylperoxydicarbonate; t-butylpero Xyacetate, t-butylperoxyisobutyrate, t-butylperoxypivalate, t-butylperoxyneodecanoate, cumylperoxyneodecanoate, t-butylperoxy-2-ethylhexanoate, t -Butylperoxy-3,5,5-
Trimethylhexanoate, t-butylperoxylaurate, t-butylperoxybenzoate, di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5
-Di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, cumylperoxyoctoate, t-
Peroxyesters such as hexylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxyneohexanoate, t-hexylperoxyneohexanoate, cumylperoxyneohexanoate; Acetyl cyclohexyl sulfonyl peroxide, t-butyl peroxy allyl carbonate, etc. are mentioned.

The organic peroxide may be used by diluting it with a hydrocarbon solution or phthalic acid ester, or absorbing it in a solid powder. A decomposition temperature of 1 for a half-life of 10 hours
A peroxide having a temperature of 20 ° C. or lower, especially, a decomposition temperature of 40
Peroxides at -100 ° C are preferred. This decomposition temperature is 12
When an organic peroxide having a temperature higher than 0 ° C. is used, the curing temperature of the molded product will be high. Further, an organic peroxide having a temperature of lower than 40 ° C. has poor handleability and deteriorates storage characteristics and productivity of the magnet composition.

The amount of these organic peroxides added may be 0.01 to 5% by weight with respect to the unsaturated polyester resin, depending on the dilution ratio and the amount of active oxygen. Further, cobalt organic acid salts such as cobalt naphthenate and cobalt octylate, β-diketones such as acetylacetone, ethyl acetoacetate and dimedone, aromatic tertiary amines such as dimethylaniline, mercaptans, triphenylphosphine,
Phosphorus compounds such as 2-ethylhexyl phosphite, fourth
It may be used in combination with an accelerator such as a primary ammonium salt, an azo compound such as azobisisobutyronitrile, an aromatic carbonyl compound, a pinacolone derivative or the like.

As the polymerization inhibitor, p-benzoquinone,
Naphthoquinone, phenanthraquinone, toluquinone, 2,
5-diphenyl-p-benzoquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxy-p-
Quinones such as benzoquinone and 2,5-diacyloxy-p-benzoquinone; hydroquinone, pt-butylcatechol, 2,5-di-t-butylhydroquinone, mono-di-t-butylhydroquinone, 2,5-di Hydroquinones such as -t-amylhydroquinone; phenols such as di-t-butyl paracresol hydroquinone monomethyl ether and alpha naphthol; organic and inorganic copper salts such as copper naphthenate; acetamidine acetate, acetamidine sulfate and the like Amidines;
Hydrazines such as phenylhydrazine hydrochloride and hydrazine hydrochloride; trimethylbenzylammonium chloride, laurylpyridinium chloride, cetyltrimethylammonium chloride, phenyltrimethylammonium chloride, trimethylbenzylammonium oxalate, di (trimethylbenzylammonium) oxalate, trimethylbenzylammonium Quaternary ammonium salts such as maleate, trimethylbenzylammonium tartrate and trimethylbenzylammonium glycolate; amines such as phenyl-β-naphthylamine, parabenzylaminophenol, di-β-naphthylparaphenylenediamine; nitrobenzene, trinitrotoluene , Nitro compounds such as picric acid; quinone dioximes, cyclo Examples include oximes such as xanone oxime; polyhydric phenols such as pyrogallol, tannic acid, resorcin; amine hydrochlorides such as triethylamine hydrochloride, dimethylaniline hydrochloride, dibutylamine hydrochloride, and the like. A mixture of two or more species can be used.

C Inorganic Phosphoric Acid Compound The inorganic phosphoric acid compound is a compound that enhances the effectiveness of the coating agent component and enhances the weather resistance of its surface by pretreating the above magnetic powder. Inorganic phosphoric acid, which should be called a representative of inorganic phosphoric acid compounds, includes phosphoric acid, hypophosphorous acid, pyrophosphoric acid, linear polyphosphoric acid, and cyclic metaphosphoric acid, in addition to phosphoric acid.

In addition to inorganic phosphoric acid, monoammonium phosphate, magnesium ammonium phosphate, and the like, and zinc phosphates, schulzeite, phosphophyllite, which form hopite, phosphoferrite, etc. on the surface of the magnetic powder,
Examples thereof include zinc-calcium phosphate-based compounds that form hopite and the like, manganese-phosphate-based compounds that form manganese-huriolite and iron-huriolite, and iron-phosphate-based compounds such as strenite and hematite that form films. The above-mentioned inorganic phosphoric acid compound is usually mixed with a chelating agent, a neutralizing agent and the like to give a treating agent. Of these inorganic phosphoric acid-based compounds, phosphoric acid, manganese phosphate-based compounds, and iron phosphate-based compounds are preferable, and these may be used alone or in combination.

If the inorganic phosphoric acid compound is surface-treated by either a wet treatment method or a dry treatment method and then heat-treated at about 100 ° C. for 10 to 30 hours, it is more stably fixed on the magnetic powder. .

The addition amount of the inorganic phosphoric acid compound varies depending on the kind and concentration thereof, but is 0.01 to 10 parts by weight with respect to 100 parts by weight of the magnetic powder. 0.05 to 7 parts by weight, particularly 0.1 to 5 parts by weight are preferred. As a result, a phosphoric acid compound film having a thickness of about 5 to 100 nm can be formed on the magnetic powder. If the amount added is less than 0.01 parts by weight, the film will not be formed sufficiently, and if it exceeds 10 parts by weight, the density of the magnetic powder will decrease and the magnetic properties and mechanical strength will decrease.

When a rare earth-iron-nitrogen alloy powder is used as the magnetic powder, if the surface is treated with an inorganic phosphoric acid compound, the resin binder can be highly filled at a ratio of 85% by weight or more, which is particularly excellent. It is expected that a resin-bonded magnet having rust resistance will be obtained.

However, it was found that it is difficult to improve the rust resistance by only the surface treatment with such a phosphoric acid compound. The reason is that the surface treatment with an inorganic substance has a lot of film defects and, in addition, a resin binder is used. This is probably because the affinity is not sufficient.

D1 Abietic acid-based compound The magnetic powder surface-treated with the phosphoric acid-based compound is then coated with abietic acid represented by the general formula (1), its isomer or a derivative thereof. C ₁₉ H _n COOH (1) (In the formula, n is an integer of 25 or more and 33 or less.)

Examples of these compounds include diterpenes such as abietic acid, neoabietic acid, levopimaric acid, valstophosphoric acid, dehydroabietic acid, dihydroabietic acid, tetraabietic acid, dextropimaric acid and isodextropimaric acid. Resin acid; and their water additives, disproportionated products, polymers such as esterified products with phenols and alcohols, ethers with glycerins, maleated products, and reaction products with metal ions.

These resin acids and various compounds thereof are generally referred to as rosins, and among resin oils obtained from plants of the family Pinaceae existing in nature, volatile substances such as essential oils are distilled off,
Alternatively, it is a residual resin after extraction and removal, which is a mixture mainly containing an abietic acid compound, an isomer thereof or a derivative thereof.

For example, trade name "Super Ester A-100" of Arakawa Chemical Industries, Ltd. contains rosin ester as a main component, and trade name "Ester gum AAG" is monoglycerin abietin ether, diglycerin abietin ether and It is a mixture of triglycerin abietin ether and the like, and the trade name "Marquide No. 2" is, for example, a mixture of maleopimaric acid-maleated rosin and the like, and an esterified product thereof. By coating the surface-treated magnetic powder with the abietic acid-based compound by a wet treatment method or a dry treatment method, a magnetic powder having more stable performance can be obtained.

The amount of the abietic acid compound added is 0.01 to 10 parts by weight based on 100 parts by weight of the magnetic powder.
0.05 to 7 parts by weight, more preferably 0.1 to 5 parts by weight are more preferable. This makes it possible to form a suitable film of the abietic acid compound on the magnetic powder. If the addition amount is less than 0.01 parts by weight, the rust resistance effect is not sufficient, and if the addition amount is more than 10 parts by weight, the density of the magnetic powder decreases, and the magnetic properties and mechanical strength also decrease.

The reason why the abietic acid-based compound can suitably coat the magnetic powder has not yet been completely elucidated, but a polycyclic hydrocarbon containing a double bond as in the general formula (2) is used. It is presumed that this is due to the structure and the unique three-dimensional structure of abietic acid having one carboxyl group.

[0050]

[Chemical 1]

D2 Aluminum Coupling Agent The magnetic powder is coated with the above-mentioned abietic acid compound and then further coated with an aluminum coupling agent.

Examples of the aluminum-based coupling agent used in the present invention include alkoxyaluminum chelates represented by the general formula (3). (RO) _2- Al-O-CR '= CH-COOR "(3) (In the formula, R, R', and R" may be the same or different, and are linear, branched or cyclic carbon. The number is an alkyl group of 1 to 8.)

As the alkyl group, if it has 1 to 8 carbon atoms, not only a straight chain but also a branched or cyclic cyclohexyl ring,
It may contain a vinyl group or a benzyl group. Particularly preferred is an alkoxyaluminum chelate having 1 to 3 alkyl groups having 1 to 4 carbon atoms. Acetoalkoxy aluminum diethylate, acetoalkoxy aluminum diisopropylate, acetoalkoxy aluminum diisobutyrate, or aluminum tris (ethylacetoacetate), aluminum monoacetylacetonate bis (ethylacetoacetate), aluminum tris (acetylacetoacetate) These can be exemplified, and one or more of these aluminum-based coupling agents can be used in combination.

The amount of addition is 0.01 to 10 parts by weight with respect to 100 parts by weight of magnetic powder. The amount is preferably 0.05 to 7 parts by weight, more preferably 0.1 to 5 parts by weight. Thereby, a suitable film of the aluminum-based coupling agent can be formed.
If the addition amount is less than 0.01 parts by weight, the rust resistance is not sufficient, and if it exceeds 10 parts by weight, the density of the magnetic powder is lowered, and the magnetic properties and the mechanical strength are lowered.

In the present invention, if the magnetic powder is surface-treated with the inorganic phosphoric acid compound (C) in advance and then coated with both the abietic acid compound and the aluminum coupling agent, a greater effect can be obtained.

The reason for this has not been completely clarified, but if the magnetic powder is coated with an abietic acid-based compound, the released reactive group reacts with the functional group when it comes into contact with the aluminum-based coupling agent. It is considered that the two particles act or interact with each other to strongly adhere to the magnetic powder.

The method of coating the magnetic powder with both the abietic acid compound and the aluminum coupling agent is not particularly limited. Each component may be added to the magnetic powder at the same time or sequentially. After diluting with a solvent etc.,
A wet treatment method of volatilizing the solvent or a dry method of directly adding the coating component during stirring may be used. However, in order to uniformly coat the surface of the magnetic powder, sequential addition treatment by a wet method is preferable.

E. Other additives Resin binder, depending on the application of the resin-bonded magnet,
Reactive diluent, unreactive diluent, various modifiers, thickeners,
Lubricants, mold release agents, UV absorbers, flame retardants and various stabilizers can be added.

Examples of the reactive diluent include styrene, fatty acid diglycidyl ether, ethylene glycol glycidyl ether, phenyl glycidyl ether and glycerin polyglycidyl ether.

Examples of the non-reactive diluent include alcohols such as ethanol and isopropanol. Examples of various modifiers include liquid polysulfide polymers and phenol-modified aromatic polymers.

Examples of the lubricant include waxes such as paraffin wax, liquid paraffin, polyethylene wax, polypropylene wax, ester wax, carnauba, and microwax, stearic acid, 1,2-
Fatty acids such as oxystearic acid, lauric acid, palmitic acid, and 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; stearic acid amide, oleic acid amide, erucic acid amide, behenic acid amide, palmitic acid amide, lauric acid amide, hydroxystearic acid amide, methylenebisstearic acid amide , Ethylenebisstearic acid amide, ethylenebislauric acid amide, distearyl adipic acid amide, ethylenebisoleic acid amide, dioleyl adipic acid amide, N-stearyl stearic acid Fatty acid amides such as acid amides; fatty acid esters such as butyl stearate; alcohols such as ethylene glycol and stearyl alcohol; polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and polyethers composed of these modified products; dimethylpolysiloxane. , Polysiloxanes such as silicon grease; fluorine compounds such as fluorine oil, fluorine grease, and fluorine-containing resin powder; inorganic compound powders such as silicon nitride, silicon carbide, magnesium oxide, alumina, silicon dioxide, molybdenum disulfide, etc. To be

As the ultraviolet absorber, phenyl salicylate, p-tert-butylphenyl salicylate, 2,4-
Dihydroxy-benzophenone, 2-hydroxy-4-
Methoxybenzophenone, 3-2'-dihydroxy-4
-Benzophenone series such as methoxybenzophenone; 2-
Benzotriazoles such as (2′-hydroxy-5′-methylphenyl) benzotriazole and 2- (2′-hydroxy-3 ′, 5′-ditertiarybutylphenyl) benzotriazole; oxalic acid anilide derivatives and the like. .
Examples of the flame retardant include antimony trioxide, sodium antimonate, organic bromine compounds, chlorinated paraffin, chlorinated polyethylene and the like.

The stabilizer is not particularly limited, but is, for example, bis (1,2,2,6,6-pentamethyl-4-).
Examples include hindered amines such as piperidyl sebacate, phenols, phosphites, and thioethers.

2. The magnetic powder coated with the resin-bonded magnet composition is finally mixed with a resin binder, and other additives are blended to form a resin-bonded magnet composition. The resin binder is either the above-mentioned thermoplastic resin or thermosetting resin.

The thermoplastic resin binder or the thermosetting resin binder is 5 to 100 parts by weight of the magnetic powder.
It is added in a proportion of 50 parts by weight. The addition amount is preferably 7 to 30 parts by weight, more preferably 10 to 15 parts by weight. 5 added
If the amount is less than part by weight, the kneading torque remarkably increases, the fluidity decreases, and molding becomes difficult. Further, if it exceeds 50 parts by weight, desired magnetic characteristics cannot be obtained.

Other additives such as reactive diluents, non-reactive diluents, various modifiers, thickeners, lubricants, release agents, ultraviolet absorbers, flame retardants and various stabilizers are resin-bonded magnets. Depending on the use of the magnetic powder (A) 100 parts by weight,
0.01 to 10% by weight, especially 0.1 to 5% by weight
Is preferred.

The resin binder is mixed by the above method,
The resin-bonded magnet composition containing other additives is
It is mixed by a known method. The mixing method is not particularly limited, for example, a mixer such as a ribbon blender, a tumbler, a Nauter mixer, a Henschel mixer, a super mixer, a planetary mixer, or a Banbury mixer, a kneader, a roll, a kneader ruder, a single screw extruder, It can be mixed using a kneader such as a shaft extruder.

3. Resin-bonded magnet The resin-bonded magnet composition described above can be molded into a resin-bonded magnet by injection molding, compression molding, extrusion molding, roll molding, transfer molding, or the like.

For thermoplastic resins, injection molding, extrusion molding,
Alternatively, it is molded by a transfer molding method or the like, and not only the magnetic characteristics and the degree of freedom of shape, but also the rust resistance, mechanical strength,
A resin-bonded magnet excellent in flexibility and heat resistance can be easily manufactured.

In the case of a thermosetting resin, it is preferable to use a mixer having a weak shearing force and a cooling function so that the curing does not proceed due to heat generation by shearing during mixing. Since the composition for resin-bonded magnet becomes a lump by mixing, this is molded by an injection molding method, a compression molding method, an extrusion molding method, a rolling molding method, a transfer molding method, or the like.

In the present invention, the injection molding method is particularly preferable regardless of the type of resin. The thermosetting resin cures in a high temperature mold during molding.

[0072]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

The following materials were used as raw materials for the resin-bonded magnet composition. A Magnetic powder / Magnetic powder 1: SmFeN-based magnetic powder, “Product name: SmFe
N alloy powder ", manufactured by Sumitomo Metal Mining Co., Ltd., anisotropic magnetic field: 2
Contains 99% of particle size of 10 kOe and particle size of 100 μm or less. -Magnetic powder 2: SmCo-based magnetic powder, "Brand name: RCo ₅ alloy", manufactured by Sumitomo Metal Mining Co., Ltd., anisotropic magnetic field: 246 kO
e, 99% particle size of 100 μm or less is contained.・ Magnetic powder 3: NdFeB-based magnetic powder, "Product name: MQP-
B ”, manufactured by Magnequench International, anisotropic magnetic field: 70 kOe, containing 33% of a particle size of 100 μm or less. -Magnetic powder 4: Strontium ferrite-based magnetic powder, "Brand name: MA-951", manufactured by Toda Kogyo Co., Ltd., anisotropic magnetic field: 70 kOe, particle size of 100 µm or less contained 99%.

B1 thermoplastic resin / nylon 12 (abbreviated as PA12), "trade name: Daiamide A-1709P", Daicel Huls Co., Ltd.
Made, average molecular weight 15,000 or less. -Polyphenylene sulfide resin (abbreviated as PPS),
"Product name: Fortron KPS W-214", manufactured by Kureha Chemical Industry Co., Ltd. The average molecular weight is 15,000 or less.

B2 thermosetting resin / unsaturated polyester resin (abbreviated as UP resin) UP resin, "trade name: Epolak N-14B", Co., Ltd.
Made by Nippon Shokubai. The average molecular weight is 5000 or less. -Vinyl ester resin (abbreviated as VE resin) "Brand name: Epolak RF-1001H", manufactured by Nippon Shokubai Co., Ltd. The average molecular weight is 5000 or less.

C Inorganic phosphoric acid or inorganic phosphoric acid compound (abbreviated as compound) Compound 1: Phosphoric acid (special grade reagent), manufactured by Kanto Chemical Co., Inc. -Compound 2: Manganese phosphate-based treatment agent "Product name: Phosnin 131", manufactured by Riko Kyosan Co., Ltd. -Compound 3: iron phosphate-based treatment agent "Product name: phosnin 259
E ", manufactured by Riko Kyosan Co., Ltd.

D1 Abietic acid compound (abbreviated as rosin) -Rosin 1: "Product name: Super Ester A-10"
0 ", manufactured by Arakawa Chemical Industry Co., Ltd. -Rosin 2: "Product name: ester gum AAG", manufactured by Arakawa Chemical Industry Co., Ltd. -Rosin 3: "Product name: Marquise No. 2", manufactured by Arakawa Chemical Industry Co., Ltd.

D2 Aluminum coupling agent (A
Al agent 1: acetoalkoxyaluminum diisopropylate, "trade name: Planeact AL-M", manufactured by Ajinomoto Co., Inc.

The resin-bonded magnet composition was manufactured by the following method. Surface treatment with phosphoric acid or phosphoric acid compound With respect to 100 parts by weight of magnetic powder, a predetermined amount of phosphoric acid or a phosphoric acid compound is dissolved in 10 parts by weight of an alcohol-based organic solvent such as IPA, and then the solution and the magnetic powder are mixed with a planetary powder. Mixing and stirring (40 rpm, 20 ° C,
After holding and stirring for 10 minutes), -760 mmHg,
Dry in a vacuum oven at 120 ° C. for 24 hours to obtain a surface-treated magnetic powder.

Coating treatment with abietic acid compound 1 part by weight per 100 parts by weight of the above-mentioned surface-treated magnetic powder
A coating solution prepared by dissolving a predetermined amount of an abietic acid-based compound in 0 part by weight of an organic solvent such as ethanol is prepared, and this and magnetic powder are sufficiently mixed and stirred in a planetary mixer (40 rpm, 20 ° C., hold, (Stirring time: 10 minutes), and then in a vacuum oven at -760 mmHg and 120 ° C for 2 minutes.
It is dried for 4 hours to obtain magnetic powder coated with an abietic acid compound.

Coating Treatment with Aluminum Coupling Agent For 100 parts by weight of the magnetic powder surface-treated as described above and further coated with the abietic acid compound, 10 parts by weight of an organic solvent such as ethanol was added to a predetermined amount. A coating solution in which an aluminum-based coupling agent is dissolved is prepared, and this and magnetic powder are sufficiently mixed and stirred in a planetary mixer (4
0 rpm, 20 ° C, holding / stirring time 10 minutes),
The coated magnetic powder is obtained by drying in a vacuum oven at -760 mmHg and 120 ° C for 24 hours.

Mixing of resin binder and preparation of composition for resin-bonded magnet A thermoplastic resin or a thermosetting resin was added to the coated magnetic powder in a predetermined ratio, and the mixture was sufficiently mixed and stirred in a planetary mixer. Then, a resin-bonded magnet composition is obtained. When using a thermoplastic resin, a 20 mmφ single extruder (L / D = 25, CR = 2.0, rotation speed = 20 rpm,
5mmφ strand die, cylinder temperature 200-32
Extrusion is performed at 0 ° C. and a die temperature of 190 ° C. to 300 ° C., and a hot-cut pelletizer is used to produce a pellet compound for molding a resin-bonded magnet of φ5 mm × 5 mm.

Injection molding method The resin-bonded magnet composition (pellet compound) thus obtained was subjected to an injection molding machine under conditions of Table 1 to obtain a diameter of 10 mm.
A resin-bonded magnet for testing having a cylindrical shape is obtained by molding to a size of × 15 mm. It should be noted that magnetic powders other than NdFeB type are molded in a mold in a magnetic field of 15 to 20 kOe.

[0084]

[Table 1]

A resin-bonded magnet sample (Example) obtained by subjecting a magnetic powder to a surface treatment and a coating treatment, mixing a resin binder and injection molding, and measuring its characteristics in the following manner,
evaluated. The resin-bonded magnet sample of the comparative example was similarly measured and evaluated.

Magnetic property evaluation The magnetic property of the sample was measured at room temperature with a Thiophie type self-recording magnetometer.・ Humidity resistant sample: Leave the sample in constant temperature and humidity at 80 ℃ and 90% humidity.
The magnetic characteristics after 500 hours were measured. After 500 hours, if the decrease rate of the coercive force of the sample is within 10%, there is no practical problem.・ Leave the rust resistant sample in a constant temperature and humidity of 80 ° C and 90% humidity,
The time until rust was generated was observed in units of 24 hours, and the rust characteristics were evaluated. If rust does not occur for 48 hours or more, there is no practical problem.

(Examples 1 to 6) Magnetic powder 1 as magnetic powder
(SmFeN magnetic powder) is first surface-treated with compound 1 (phosphoric acid), and then rosin 1 (abietic acid compound) and Al agent 1 (aluminum coupling agent)
Then, PA12 (nylon 12) was mixed to prepare a resin-bonded magnet composition of the present invention, which was injection-molded to produce a resin-bonded magnet. The magnetic properties and the like of this magnet were investigated, and the results are shown in Table 2. Next, an experiment was carried out using Compound 2 (manganese phosphate-based) or Compound 3 (iron phosphate-based) instead of Compound 1 (phosphoric acid). Further, an experiment was conducted by changing the amount of rosin 1. These results are also shown in Table 2.

[0088]

[Table 2]

(Examples 7 to 11) According to the above procedure, the magnetic powder 1
Was first surface-treated with Compound 1 (phosphoric acid), then coated with Rosin 2 or Rosin 3 (abietic acid compound), further coated with Al agent 1 (aluminum coupling agent), and mixed with nylon 12. , A composition was prepared. This was injection-molded, and the magnetic properties and the time until the occurrence of rust were measured. The results are shown in Table 3. Experiments were also performed when rosin 1 was used in combination with rosin 2 or rosin 3 and when rosin 2 and rosin 3 were used. The results are also shown in Table 3.

[0090]

[Table 3]

(Examples 12 to 15) In the same manner as described above, the magnetic powder 1 was first surface-treated with the compound 1 (phosphoric acid), then coated with the rosin 1 (abietic acid compound), and the Al agent 1 was further added.
After coating by changing the amount of (aluminum-based coupling agent), nylon 12 was mixed to prepare a composition. This was injection-molded, its magnetic characteristics and the time until rust generation were measured, and the results are shown in Table 4.

[0092]

[Table 4]

(Examples 16 to 23) The magnetic powder 1 was first surface-treated with the compound 1 in the same manner as in the above example, then the abietic acid compound (rosin 1), and the aluminum coupling agent (Al agent 1). ), And instead of PA12 as a binder, PPS was mixed and injection molded. The magnetic properties and the time until the occurrence of rust were measured and shown in Table 5. Experiments were also performed when the binder was UP resin or VE resin, magnetic powder 2 and magnetic powder 3 were used instead of magnetic powder 1, or magnetic powder 1 and magnetic powder 4 were mixed, and the results are also shown in Table 5.

[0094]

[Table 5]

Comparative Examples 1 to 8 Magnetic powder 1 was not surface-treated with compound 1 (phosphoric acid) and was not coated with rosin 1 (abietic acid compound) or Al agent 1 (aluminum coupling agent). Nylon 12 was mixed with the above to prepare a composition for comparison, which was injection-molded. Magnetic properties,
The time to rust generation was measured and shown in Table 6. Magnetic powder 1
Was surface-treated with Compound 1, was not coated with any of Rosin 1 and Al agent 1, and was mixed with nylon 12 for injection molding, and was not surface treated with phosphoric acid compound 1 and was treated with Rosin 1 or Al agent 1. Experiments were also carried out in the case of coating with any one of 1, No. 1 and Nylon 12 and injection molding. On the other hand, an experiment was carried out in the case where the surface treatment was performed with the compound 1, the rosin 1 or the Al agent 1 was coated, the nylon 12 was mixed, injection molding was performed, and further, the magnetic powder 1 and the magnetic powder 4 were mixed. These results are also shown in Table 6.

[0096]

[Table 6]

From the results of these examples, when the magnetic powder was first surface-treated with a phosphoric acid-based compound, then coated with an abietic acid-based compound and an aluminum-based coupling agent, and mixed with a resin binder, the magnetic properties were lowered. It can be seen that the rust resistance can be improved without the need.

On the other hand, according to the results of the comparative example, the magnetic powder was not surface-treated with the phosphoric acid type compound, or even if the surface treatment was performed, it was not coated with both the abietic acid type compound and the aluminum type coupling agent. , It turns out that the initial effect is not exhibited.

[0099]

As described above, according to the resin-bonded magnet composition of the present invention, magnetic properties are excellent, there is a degree of freedom in shape, rust properties that have hitherto not been obtained, mechanical strength,
A resin-bonded magnet having improved flexibility and heat resistance can be provided. Further, this magnet can be utilized in a wide range of fields such as general home appliances, communication / audio equipment, medical equipment, and general industrial equipment, and its industrial value is extremely large.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4K018 BA18 BC28 BC29 KA46                 5E040 AA03 AA19 BB03 BC05 CA01                       HB14 NN04 NN05                 5E062 CD05 CE02 CE03 CE04 CG07

Claims (8)

[Claims] 1. A resin-bonded magnet composition comprising a magnetic powder (A) and a resin binder (B), wherein the magnetic powder (A) is surface-treated with an inorganic phosphoric acid compound (C) in advance, and then further. A resin-bonded magnet composition, which is coated with an abietic acid compound (D1) and an aluminum coupling agent (D2). 2. The magnetic powder (A) has an anisotropic magnetic field (H
2. A) is 50 kOe or more.
The composition for resin-bonded magnets according to 1. 3. The magnetic powder (A) is 30% by weight of the magnetic powder having a particle diameter of 100 μm or less based on the total amount of the magnetic powder (A).
The composition for a resin-bonded magnet according to claim 1, containing the above. 4. The composition for resin-bonded magnet according to claim 1, wherein the magnetic powder (A) is a rare earth-iron-nitrogen system. 5. The abietic acid compound (D1) is at least one compound selected from abietic acid represented by the following general formula (1), an isomer thereof, or a derivative thereof. The composition for resin-bonded magnets according to claim 1. C ₁₉ H _n COOH (1) (In the formula, n is an integer of 25 or more and 33 or less.) 6. An aluminum-based coupling agent (D2)
Is an alkoxyaluminum chelate, The composition for resin-bonded magnets according to claim 1, wherein. 7. The content of the inorganic phosphoric acid compound (C), the abietic acid compound (D1) or the aluminum coupling agent (D2) is 0.01 per 100 parts by weight of the magnetic powder (A). The composition for a resin-bonded magnet according to claim 1, wherein the composition is 10 to 10 parts by weight. 8. The resin-bonded magnet composition according to claim 1 is molded by any molding method selected from an injection molding method, a compression molding method, an extrusion molding method, and a rolling molding method. Resin-bonded magnet made by.