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JP2004079982A - Multilayer structure of bonded magnet having two or more kinds of various magnetic properties - Google Patents

Multilayer structure of bonded magnet having two or more kinds of various magnetic properties Download PDF

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JP2004079982A
JP2004079982A JP2002280064A JP2002280064A JP2004079982A JP 2004079982 A JP2004079982 A JP 2004079982A JP 2002280064 A JP2002280064 A JP 2002280064A JP 2002280064 A JP2002280064 A JP 2002280064A JP 2004079982 A JP2004079982 A JP 2004079982A
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Prior art keywords
magnetic powder
magnetic properties
magnetic
nylon
bonded magnet
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JP2002280064A
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Japanese (ja)
Inventor
Kenji Ono
小野 賢治
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ONO GOMU KOGYO CO Ltd
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ONO GOMU KOGYO CO Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer structure of a bonded magnet having two or more kinds of various magnetic properties by forming magnetic powder material having an optimum magnetism suitable for a service part with resin, various rubber or the like and sheeting it. <P>SOLUTION: The bonded magnets are double formed with magnetic powder having high magnetic properties provided inside diameter part and outside diameter part of a low cost bonded magnet which is molded by resin and has low magnetic properties. Various rubber magnetic sheets are made by laminating or integrating the low cost bonded magnetic sheet which has the low magnetic properties on one side with the bonded magnetic sheet using magnetic powder material having the high magnetic properties on the other side. <P>COPYRIGHT: (C)2004,JPO

Description

【0001】
【産業上の利用分野】
本発明は、磁気特性の高いボンデットマグネットを廉価で提供できることに関する。
【0002】
【従来の技術】
従来は磁気特性値をあげるために、磁気特性の高い磁性粉末を使用したり、磁気特性の低い磁性粉末と磁気特性の高い磁性粉末を混ぜることの技術はあるが、前者の場合顧客要求磁気特性は出るメリットはあるが価格が高くなるというデメリットがあった。また、後者の場合、価格は安くなるが、顧客要求磁気特性が思ったほどに出ないというデメリットがあり、価格が安く、磁気特性の高いボンデットマグネットの開発が進められている。
【0003】
【発明が解決しようとする課題】
しかしながら、磁気特性の高い磁性粉末を使用する場合、磁性粉末の価格が高いため製品価格を下げることは非常に困難であり、自ずとその用途も制限されることも多かった。本発明は、かかる状況に鑑みてなされたものであり、磁気特性の高い磁性粉末で作られたボンデットマグネットと同様な磁気特性を持つ一体化されたボンデットマグネットを提供することを目的とする。
【0004】
【課題を解決するための手段】
本発明者らは、鋭意研究を重ねた結果、樹脂や各種ゴムポリマーに特定の磁性粉末および各薬品を配合することにより上記目的を達成しうることを見いだし、この知見に基づいて本発明を完成するに至った。すなわち、本発明は樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が低く、安価な磁性粉末を施した成形品Aと樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が高い磁性粉末材料を施した材料Bを二重成形し一体化されたものと、ゴム(NBR系、アクリル系、CPE系等のゴムポリマー)に磁気特性が低く、安価な磁性粉末を施した磁性粉末シートCと磁気特性の高い磁性粉末材料を施した磁性粉末シートDとを張り合わせ、または一体化したボンデットマグネットシートを提供するものである。以下、本発明を具体的に説明する。
【0005】
本発明における磁性粉末材料と樹脂、各種ゴムとのボンデットマグネットの製造方法は公知の技術であり、本発明においては二種類以上の異なる磁気特性をもつボンデットマグネットの多層構造体によるものである。
【0006】
また、本発明における磁性粉末は、一般にフェライトと称される粉末であり、例えばバリウムフェライト、ストロンチウムフェライト、鉛フェライト、カルシウムフェライト、ネオジー鉄−ボロン、サマリウム−コバルト、サマリウム−鉄−窒素、マンガン−アルミ−炭素などがあげられる。これらの中でもバリウムフェライト及びストロンチュウムフェライトとネオジー鉄ボロン、サマリウム−コバルト、サマリウム−鉄−窒素、マンガン−アルミ−炭素との組み合わせが好適である。
【0007】
成分100重量部に対する磁性粉末の配合量は300〜1400重量部であり、150〜1300重量部が好ましく、とりわけ200〜1200重量部が好適である。磁性粉末の配合量が100重量部未満では磁性力に乏しく、1400重量部を越すと柔軟性及び加工性が低下するので好ましくない。
【0008】
本発明における二重成形とは、樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が低く、安価な磁性粉末を施した成形品Aに樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が高い磁性粉末材料を施した材料を再成形Bし一体化したものである。
【0009】
また、本発明における各種ゴムマグネットシートの積層において片面は磁気特性が低く、安価なボンデットマグネットCで、片面は磁気特性が高い磁性粉末材料を使用したボンデットマグネットシートDを張り合わせ、または一体化されたものである。
【0010】
本発明において二重成形及び異種磁性粉末を施したボンデットマグネットの重量比率は例えば6ナイロンの場合、成分100重量部に対するバリウムフェライト及びストロンチウムフェライトの配合量は500〜1500重量部であり600〜1300重量部が好ましく、上記の組成物を混合した材料を公知の技術により一次成形をする。
【0011】
公知の技術により一次成形されたものの表面に、成分100重量部に対するネオジー鉄ボロン、サマリウム−コバルト、サマリウム−鉄−窒素、マンガン−アルミ−炭素の配合量は500〜1500重量部であり600〜1300重量部が好ましく、上記の組成物を混合した材料を二次成形する。
【0012】
一次成形された成形物と、二次成形された成形物の厚みは一次成形物が0.3mmから上限はなく、二次成形物は0.1mmから上限はない。とりわけ製品を安価にするための手段としては、二次成形物の厚みは0.3mm以上で一次成形物との容積比率は50%以下が好ましく、0.5mm以上で容積比率50%以下が好適である。二次成形された厚みが0.1mm未満では加工性の難易度が上がる。一方、一次成形物との容積比率が50%を超えた場合にはコストパフォーマンスが出なく、安価の製品を供給することが問題となる。
【0013】
また、例えばゴムマグネットシートの積層において、成分100重量部に対するバリウムフェライト及びストロンチウムフェライトの配合量は500〜1500重量部であり600〜1300重量部が好ましく、上記の組成物を混合した材料を押し出し成形、カレンダーロール等による公知の技術によりシート化する。
【0014】
公知の技術によりシート化されたものと、成分100重量部に対するネオジー鉄−ボロン、サマリウム−コバルト、サマリウム−鉄−窒 素、マンガン−アルミ−炭素の配合量は500〜1500重量部であり600〜1300重量部が好ましく、上記の組成物を混合した材料を押し出し成形、カレンダーロール等による公知の技術によりシート化する。
【0015】
一次成形シートと、二次成形シートの厚みは一次成形シートが0.3mmから上限はなく、二次成形物は0.1mmから上限はない。とりわけ製品を安価にするための手段としては、二次成形シートの厚みは0.3mm以上で一次成形シートとの容積比率は50%以下が好ましく、0.5mm以上で容積比率50%以下が好適である。二次成形された厚みが0.1mm未満では加工性の難易度が上がる。一方、一次成形物との容積比率が50%を超えた場合にはコストパフォーマンスが出なく、安価の製品を供給することが問題となる。
【0016】
一次成形シートと、二次成形シートはカレンダーロール等の公知の技術により積層し一体化されたり、張り合わせて使用される。
【0017】
【実施例】
以下、本発明を実施例によりさらに詳しく説明する。なお、磁気特性評価は次の方法に拠った。
磁気特性
直流磁化特性測定装置(電子磁気(株))を用いて試料(寸法:φ17.2×12t)、電磁石巻数:960turns巻数:27turns 測定サイクル:15secで磁気特性を測定した。
【0018】
また、一次成形シートには(A)成分として塩素含有量が30重量%の非結晶性塩素化ポリエチレンと配合薬品を用い、(B)成分として平均粒径が1μmであるストロンチウムフエライト(以下St−Frという)を用いた。二次成形シートには(A)成分として塩素含有量が30重量%の非結晶性塩素化ポリエチレンと配合薬品を用い、(B)成分として平均粒径が1μmであるネオジ−鉄−ボロン(以下Nd−Fe−Bという)を用いた。
【0019】
磁気特性は残留磁束密度(以下Brという)、保持力(以下bHcという)、固有保持力(以下iHcという)最大エネルギー積(以下(BH)maxという)を計測した。
【0020】
表1に一次成形シートと二次成形シートの厚みによる特性値の結果と、磁気特性の低い磁性粉末と磁気特性の高い磁性粉末を混ぜることにより磁気特性の変化を表2に示す。
【0021】
【表1】

Figure 2004079982
【0022】
【表2】
Figure 2004079982
Figure 2004079982
【0023】
【発明の実施の形態】
発明の一実施形態を、図1に示す。ボンデットマグネット多層構造体の積層物は磁気特性の異なる成形物を一体化したものである。一次成形品Aは磁気特性が低く安価な磁性粉末を使用し、その一次成形品の内径側に磁気特性が高い磁性粉末を使用した材料により二次成形Bされる。また、マグネットシートの積層において片面は磁気特性が低く、安価なボンデットマグネットCで、片面は磁気特性が高い磁性粉末材料を使用したボンデットマグネットシートDを張り合わせ、または一体化されたものである。
【0024】
【発明の効果】
本発明によって得られる二種類以上の異なる磁気特性をもつボンデットマグネットの多層構造体は、強磁性が良好であるばかりでなく、従来の磁気特性が同じ製品と比較して安価であり、磁気特性の低い磁性粉末と磁気特性の高い磁性粉末を混ぜたものと比較しても磁気特性は高い数値を示している。また従来の技術にない顧客要求磁気特性を持たせながら安価な製品を供給できるメリットがあるので下記の如き方面に使用することができる。
(1)電子機器の磁石材
(2)自動車用、発電用等のマイクロモーター材
(3)磁気選別機用磁石材[0001]
[Industrial applications]
The present invention relates to providing a bonded magnet having high magnetic properties at a low cost.
[0002]
[Prior art]
Conventionally, there is a technology of using magnetic powder with high magnetic properties or mixing magnetic powder with low magnetic properties and magnetic powder with high magnetic properties in order to increase the magnetic property value. There is a merit that comes out, but there was a demerit that the price became high. In the latter case, although the price is low, there is a demerit that the magnetic properties required by the customer are not as high as expected, and the development of bond magnets with low prices and high magnetic properties has been promoted.
[0003]
[Problems to be solved by the invention]
However, when a magnetic powder having high magnetic properties is used, it is very difficult to reduce the product price because the price of the magnetic powder is high, and the use thereof is often limited naturally. The present invention has been made in view of such circumstances, and has as its object to provide an integrated bonded magnet having magnetic properties similar to those of a bonded magnet made of magnetic powder having high magnetic properties. .
[0004]
[Means for Solving the Problems]
The present inventors have conducted intensive studies and found that the above object can be achieved by blending a specific magnetic powder and various chemicals with a resin or various rubber polymers, and based on this finding, completed the present invention. I came to. That is, the present invention relates to a molded article A obtained by applying an inexpensive magnetic powder to a resin (a thermoplastic resin such as a 6-nylon or 12-nylon type) and a resin (a 6-nylon-type or 12-nylon-type thermoplastic resin). (Resin) and a magnetic powder material with a high magnetic property applied to the material B, which is formed by double molding and integrated, and rubber (rubber polymer such as NBR, acrylic and CPE) has low magnetic properties and is inexpensive An object of the present invention is to provide a bonded magnet sheet in which a magnetic powder sheet C provided with a magnetic powder and a magnetic powder sheet D provided with a magnetic powder material having high magnetic properties are bonded or integrated. Hereinafter, the present invention will be described specifically.
[0005]
The method for producing a bonded magnet of a magnetic powder material, a resin, and various rubbers according to the present invention is a known technique, and the present invention is based on a multilayer structure of two or more types of bonded magnets having different magnetic properties. .
[0006]
Further, the magnetic powder in the present invention is a powder generally called ferrite, for example, barium ferrite, strontium ferrite, lead ferrite, calcium ferrite, neodymium iron-boron, samarium-cobalt, samarium-iron-nitrogen, manganese-aluminum -Carbon and the like. Of these, combinations of barium ferrite and strontium ferrite with neodymium iron boron, samarium-cobalt, samarium-iron-nitrogen, and manganese-aluminum-carbon are preferred.
[0007]
The mixing amount of the magnetic powder with respect to 100 parts by weight of the component is 300 to 1400 parts by weight, preferably 150 to 1300 parts by weight, particularly preferably 200 to 1200 parts by weight. If the compounding amount of the magnetic powder is less than 100 parts by weight, the magnetic force is poor, and if it exceeds 1400 parts by weight, flexibility and processability are undesirably reduced.
[0008]
The double molding in the present invention means that a molded article A obtained by applying an inexpensive magnetic powder to a resin (a thermoplastic resin such as a 6-nylon or 12-nylon) and a resin (6-nylon or 12-nylon) is used. A material obtained by applying a magnetic powder material having high magnetic properties to a thermoplastic resin such as a thermoplastic resin) is remolded B and integrated.
[0009]
In the lamination of various rubber magnet sheets according to the present invention, one side is a low-price bonded magnet C having low magnetic properties and one side is bonded or integrated with a bonded magnet sheet D using a magnetic powder material having high magnetic properties. It was done.
[0010]
In the present invention, the weight ratio of the bonded magnet subjected to the double molding and the different magnetic powder is, for example, in the case of 6 nylon, the compounding amount of barium ferrite and strontium ferrite with respect to 100 parts by weight of the component is 500 to 1500 parts by weight, and 600 to 1300 parts. The parts by weight are preferable, and the material obtained by mixing the above composition is subjected to primary molding by a known technique.
[0011]
The amount of neodymium iron boron, samarium-cobalt, samarium-iron-nitrogen, and manganese-aluminum-carbon with respect to 100 parts by weight of the component is 500 to 1500 parts by weight, and Parts by weight are preferred, and a material obtained by mixing the above composition is subjected to secondary molding.
[0012]
The thicknesses of the primary molded product and the secondary molded product have no upper limit from 0.3 mm for the primary molded product, and have no upper limit from 0.1 mm for the secondary molded product. In particular, as means for reducing the cost of the product, the thickness of the secondary molded product is preferably 0.3 mm or more, and the volume ratio with the primary molded product is preferably 50% or less, and the volume ratio of 0.5 mm or more and 50% or less is preferred. It is. If the thickness of the secondary formed is less than 0.1 mm, the difficulty of workability increases. On the other hand, when the volume ratio with the primary molded product exceeds 50%, cost performance does not appear and supply of inexpensive products becomes a problem.
[0013]
In addition, for example, in the lamination of the rubber magnet sheet, the compounding amount of barium ferrite and strontium ferrite with respect to 100 parts by weight of the component is 500 to 1500 parts by weight, preferably 600 to 1300 parts by weight, and a material obtained by mixing the above composition is extruded. Into a sheet by a known technique using a calender roll or the like.
[0014]
The amount of neodymium-boron, samarium-cobalt, samarium-iron-nitrogen, and manganese-aluminum-carbon based on 100 parts by weight of the component formed into a sheet by a known technique is 500 to 1500 parts by weight, and It is preferably 1300 parts by weight, and the material obtained by mixing the above composition is formed into a sheet by a known technique such as extrusion molding and calender roll.
[0015]
The thickness of the primary molded sheet and the secondary molded sheet has no upper limit from 0.3 mm for the primary molded sheet, and has no upper limit from 0.1 mm for the secondary molded product. In particular, as a means for reducing the cost of the product, the thickness of the secondary molded sheet is preferably 0.3 mm or more, and the volume ratio with the primary molded sheet is preferably 50% or less, and the volume ratio of 0.5 mm or more and 50% or less is preferred. It is. If the thickness of the secondary formed is less than 0.1 mm, the difficulty of workability increases. On the other hand, when the volume ratio with the primary molded product exceeds 50%, cost performance does not appear and supply of inexpensive products becomes a problem.
[0016]
The primary molded sheet and the secondary molded sheet are laminated and integrated by a known technique such as a calender roll, or used by laminating.
[0017]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the magnetic property evaluation was based on the following method.
Magnetic properties Using a direct current magnetization property measuring device (Electronic Magnetics Co., Ltd.), the magnetic properties were measured with a sample (dimensions: φ17.2 × 12 t), electromagnet turns: 960 turns, turns: 27 turns, measurement cycle: 15 sec.
[0018]
For the primary molded sheet, non-crystalline chlorinated polyethylene having a chlorine content of 30% by weight and a compounding chemical are used as the component (A), and strontium ferrite (hereinafter referred to as St-) having an average particle size of 1 μm is used as the component (B). Fr). A non-crystalline chlorinated polyethylene having a chlorine content of 30% by weight and a compounding chemical are used as the component (A) for the secondary molded sheet, and neodi-iron-boron (hereinafter referred to as component (B)) having an average particle size of 1 μm is used as the component (B). Nd-Fe-B).
[0019]
The magnetic properties were measured by a residual magnetic flux density (hereinafter referred to as Br), a coercive force (hereinafter referred to as bHc), and a specific energy (hereinafter referred to as iHc) maximum energy product (hereinafter referred to as (BH) max).
[0020]
Table 1 shows the results of the characteristic values depending on the thickness of the primary molded sheet and the secondary molded sheet, and changes in the magnetic characteristics by mixing a magnetic powder having low magnetic characteristics and a magnetic powder having high magnetic characteristics.
[0021]
[Table 1]
Figure 2004079982
[0022]
[Table 2]
Figure 2004079982
Figure 2004079982
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of the invention is shown in FIG. The laminate of the bonded magnet multilayer structure is obtained by integrating molded products having different magnetic properties. The primary molded product A is made of an inexpensive magnetic powder having low magnetic properties, and the secondary molding B is performed using a material using magnetic powder having a high magnetic characteristic on the inner diameter side of the primary molded product. Further, in the lamination of the magnet sheets, one side is an inexpensive bonded magnet C having low magnetic properties, and one side is bonded or integrated with a bonded magnet sheet D using a magnetic powder material having high magnetic properties. .
[0024]
【The invention's effect】
The multilayer structure of the bonded magnet having two or more kinds of different magnetic properties obtained by the present invention has not only good ferromagnetism but also inexpensiveness as compared with a product having the same conventional magnetic properties. Even when compared with a mixture of a magnetic powder having a low magnetic powder and a magnetic powder having a high magnetic property, the magnetic property shows a high value. Further, there is an advantage that an inexpensive product can be supplied while having the magnetic properties required by the customer, which is not available in the conventional technology. Therefore, it can be used in the following directions.
(1) Magnet materials for electronic equipment (2) Micromotor materials for automobiles, power generation, etc. (3) Magnet materials for magnetic separators

Claims (3)

樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が低く、安価な磁性粉末を施した成形品Aと樹脂(6ナイロン系、12ナイロン系等の熱可塑性樹脂)に磁気特性が高い磁性粉末材料を施した材料Bを二重成形し一体化されたもの。Magnetic properties of resin (thermoplastic resin such as 6 nylon and 12 nylon) and resin (thermoplastic resin such as 6 nylon and 12 nylon) having low magnetic properties to resin (thermoplastic resin such as 6 nylon and 12 nylon) and inexpensive magnetic powder A material obtained by double molding and integrally forming the material B coated with a high magnetic powder material. ゴム(NBR系、アクリル系、CPE系等のゴムポリマー)に磁気特性が低く、安価な磁性粉末を施した磁性粉末シートCと磁気特性の高い磁性粉末材料を施した磁性粉末シートDとを張り合わせ、または一体化したボンデットマグネットシート。A magnetic powder sheet C made of rubber (rubber polymer such as NBR, acrylic or CPE) having low magnetic properties and inexpensive magnetic powder and a magnetic powder sheet D made of magnetic powder material having high magnetic properties are laminated. Or an integrated bonded magnet sheet. 磁性粉末がバリウムフェライト、ストロンチウムフェライト、ネオジウム−鉄−ボロン、サマリウム−コバルト、サマリウム−鉄−窒素、マンガン−アルミ−炭素、鉛フェライト、カルシウムフェライトであり、かつ平均粒径が0.1μm〜20μmである請求項1、請求項2記載の一体化したボンデットマグネット。The magnetic powder is barium ferrite, strontium ferrite, neodymium-iron-boron, samarium-cobalt, samarium-iron-nitrogen, manganese-aluminum-carbon, lead ferrite, calcium ferrite, and has an average particle size of 0.1 μm to 20 μm. The integrated bonded magnet according to claim 1 or 2, wherein
JP2002280064A 2002-08-20 2002-08-20 Multilayer structure of bonded magnet having two or more kinds of various magnetic properties Pending JP2004079982A (en)

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