JP2006073174A - Magnetic recording medium - Google Patents
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本発明は、従来のように磁気記録媒体が支持体上に配設されたディスクやテープとは異なる形状であり、高温・多湿のような、いわゆる“苛酷な環境”に晒されても記録情報を保持できる個体認証デバイスである、支持体それ自体が磁気記録媒体でもある書き換え可能型高耐久磁気記録媒体に関する。 The present invention has a shape different from that of a conventional disk or tape in which a magnetic recording medium is disposed on a support, and recorded information even when exposed to a so-called "harsh environment" such as high temperature and humidity. In particular, the present invention relates to a rewritable high durability magnetic recording medium in which a support itself is also a magnetic recording medium.
従来、磁気記録、光磁気記録、光ディスク、半導体メモリ、誘電体メモリなど、各種の記録技術の進展は著しく、より高密度に情報を記録することを目指して研究開発が進んでいる。しかしながら、これらの技術は清浄雰囲気、低振動、通常生活している温湿度領域などの、極限られた良好な環境下でしか使用できない惰弱な技術になってきている。一方で、水熱処理により殺菌消毒を行う手術器具の使用履歴の記録、クリーニングのタグ、魚や肉などのトレーサビリティを行うためのメモリ、家電製品や自動車部品など、スチーム洗浄を要するリサイクル部品の使用履歴などを記録する耐環境性を備えたメモリが要求され始めている。 Conventionally, various recording technologies such as magnetic recording, magneto-optical recording, optical disks, semiconductor memories, and dielectric memories have made remarkable progress, and research and development have been progressing with the aim of recording information at a higher density. However, these technologies have become weak technologies that can be used only in a limited and favorable environment such as a clean atmosphere, low vibration, and a normal temperature and humidity range. On the other hand, use history of surgical instruments that are sterilized and disinfected by hydrothermal treatment, cleaning tags, memory for traceability of fish and meat, usage history of recycled parts that require steam cleaning, such as home appliances and automobile parts, etc. There is an increasing demand for a memory having an environment resistance for recording the image.
現在の個体認証メモリ技術は主にバーコードおよびＩＣタグによって支えられている。紙に印刷するバーコードについては、コストはほぼ０円、ＩＣタグは大量生産した場合には一つ数十円である。また、現在は、ある程度の高温まで耐えられるバーコードおよびICタグが開発されている。しかしながら、バーコードは情報の書き換えができず、耐熱温度が３００℃程度のものになるとコストが数十〜数百円と高くなる。ＩＣタグは情報の書き換えは出来るが、耐熱温度約２００℃のものではコストが一つ数百円となるため、実用に供するには、価格が高すぎる。 Current personal identification memory technology is mainly supported by barcodes and IC tags. For barcodes printed on paper, the cost is almost 0 yen, and for an IC tag in mass production, it is several tens of yen. At present, barcodes and IC tags that can withstand high temperatures are being developed. However, the barcode cannot be rewritten, and the cost increases to several tens to several hundreds of yen when the heat resistant temperature is about 300 ° C. The IC tag can rewrite information, but if it has a heat-resistant temperature of about 200 ° C., the cost is several hundred yen, so it is too expensive for practical use.
ところで、特許文献１には、磁性体粉末と非磁性体粉末とを焼結した焼結体を機械加工したスパッタリング用ターゲットが開示されている。 By the way, Patent Document 1 discloses a sputtering target obtained by machining a sintered body obtained by sintering a magnetic powder and a non-magnetic powder.
即ち、特許文献１には、主として磁気記録媒体として用いられるＣｏ系磁性膜を形成するために使用されるＣｏ系ターゲットが記載されている。そして、Ｃｏを主体とし、溶解材として飽和磁束密度が０．１Ｔ未満となる合金組成のターゲットを製造するに際し、その原料を非磁性粉末と磁性体粉末を混合し、焼結により飽和磁束密度を０．１Ｔ以上となるように調整することが開示されている。 That is, Patent Document 1 describes a Co-based target used for forming a Co-based magnetic film mainly used as a magnetic recording medium. Then, when producing a target having an alloy composition with Co as a main component and a saturation magnetic flux density of less than 0.1 T as a melting material, the raw material is mixed with non-magnetic powder and magnetic powder, and the saturation magnetic flux density is obtained by sintering. It is disclosed that the adjustment is performed to be 0.1 T or more.
この得られたＣｏ系ターゲットを用いて形成されたＣｏ合金系磁気記録膜は、保磁力１６０ｋＡ／ｍ（２０１０６Ｏｅ）以上、残留磁束密度膜厚積１３０Ｇμｍ以下の特性を有するとされている。 A Co alloy-based magnetic recording film formed using the obtained Co-based target is characterized by having a coercive force of 160 kA / m (20106 Oe) or more and a residual magnetic flux density film thickness product of 130 Gμm or less.
しかしながら、ターゲットそれ自体は、磁気記録媒体として用いられるものではない。
このように、現在は、既存技術の適用範囲を拡張して苛酷な環境下でも使用可能とするための研究・開発は行われているが、苛酷な環境下での使用を第一の目的としたメモリの開発は行われていない。 In this way, research and development are currently underway to expand the application range of existing technologies and enable them to be used in harsh environments, but their primary purpose is to use them in harsh environments. No memory has been developed.
本発明は、従来の問題点に鑑みてなされたものであり、本発明の磁気記録媒体は汎用性を重視し、水没してもメモリ機能を失わず、耐振動・耐久性に優れ、高低温・多湿や高濃度の放射線にさらされても耐え得るような書き換え可能型磁気記録媒体を提供することにある。 The present invention has been made in view of the conventional problems, and the magnetic recording medium of the present invention emphasizes versatility, does not lose the memory function even when submerged, has excellent vibration resistance and durability, and has a high temperature and low temperature. The object is to provide a rewritable magnetic recording medium that can withstand exposure to high humidity and high concentrations of radiation.
請求項１に係る発明は、非磁性金属粉と磁性粉を混合・焼結して得られた焼結体からなることを特徴とする磁気記録媒体である。 The invention according to claim 1 is a magnetic recording medium comprising a sintered body obtained by mixing and sintering nonmagnetic metal powder and magnetic powder.
また、請求項２に係る発明は、非磁性金属粉と磁性粉を混合・焼結して得られた焼結体を加圧成形加工または切断研磨加工することにより被装着物に取り付けるための支持体を構成したことを特徴とする磁気記録媒体である。 In addition, the invention according to claim 2 is a support for attaching a sintered body obtained by mixing and sintering nonmagnetic metal powder and magnetic powder to an object to be mounted by pressure molding or cutting and polishing. A magnetic recording medium characterized in that a body is formed.
請求項３に係る発明では、該非磁性金属粉として銅（Ｃｕ）やアルミニウム（Ａｌ）の中から一つを用いるようにした。また、請求項４に係る発明では、該磁性粉として磁性酸化物を用いるようにした。また、請求項５に係る発明では、支持体の表面に酸化防止膜を設けたものである。 In the invention according to claim 3, one of copper (Cu) and aluminum (Al) is used as the nonmagnetic metal powder. In the invention according to claim 4, a magnetic oxide is used as the magnetic powder. In the invention according to claim 5, an antioxidant film is provided on the surface of the support.
ディスクやテープのような従来の磁気記録媒体とは異なり、下記（１）〜（４）のような顕著な効果を有する。
（１）苛酷な温湿度にも耐えられ、水没しても使用でき、耐振動性、耐侵食性、耐腐食性に優れ、塵埃環境にも耐えられ、しかも低コストであり書き換えが可能な、高耐久磁気メモリを容易に実現することができる。
（２）非磁性金属粉と磁性粉を均一になるように混合、焼結し、所望の形状に加工した磁気記録媒体とすることで、苛酷な条件下でもメモリとしての機能を失わず、記録情報を再生できるメモリが得られる。
（３）情報の書き換えができるためシーケンシャルな使用が可能であり、耐熱温度の目標値は４００℃（これまでの研究で２００℃に耐えられることを確認済み）で、更にコストが非常に安く、一つ当たり０．１円以下であるという特徴をもつ。
（４）現在では家電リサイクル法を契機に、リサイクルの促進があらゆる分野で推奨されている。自動車のリサイクル部品産業は２００４年にはおよそ１５５億円に達しており、今後も年々増加する見通しである。たとえば自動車の修理歴、検査日時などを記録する素子、家電製品などのリサイクル部品の使用履歴を記録する素子を作製するには、耐熱温度だけでなく耐風化性も考慮する必要がある。しかしながら、耐環境性を備え、低コストで書き換え可能なメモリは本発明の磁気記録媒体をおいて今のところ他には存在しない。本発明の磁気記録媒体が個体認証素子として最も効果を発揮することができるのはリサイクル産業である。
Unlike conventional magnetic recording media such as disks and tapes, there are significant effects as described in (1) to (4) below.
(1) It can withstand harsh temperature and humidity, can be used even under water, has excellent vibration resistance, erosion resistance, and corrosion resistance, can withstand dusty environment, and can be rewritten at low cost. A highly durable magnetic memory can be easily realized.
(2) Non-magnetic metal powder and magnetic powder are mixed and sintered in a uniform manner to obtain a magnetic recording medium that has been processed into a desired shape, so that the memory function is not lost even under severe conditions. A memory capable of reproducing information is obtained.
(3) Sequential use is possible because the information can be rewritten, and the target value of the heat-resistant temperature is 400 ° C (confirmed that it can withstand 200 ° C in the past research), and the cost is very low, It is characterized by a price of 0.1 yen or less.
(4) Currently, promotion of recycling is recommended in all fields, triggered by the Home Appliance Recycling Law. The automobile recycling parts industry reached approximately 15.5 billion yen in 2004 and is expected to increase year by year. For example, in order to produce an element for recording the repair history of automobiles, the date and time of inspection, and the element for recording the use history of recycled parts such as home appliances, it is necessary to consider not only the heat resistance temperature but also weathering resistance. However, there is no other environment-resistant memory that can be rewritten at a low cost with the magnetic recording medium of the present invention. It is the recycling industry that the magnetic recording medium of the present invention is most effective as an individual authentication element.
従来の磁気記録テープ媒体は、非磁性基板上に磁性紛とバインダを混合し、塗布または蒸着した微粒子媒体であったが、本発明の磁気記録媒体は、非磁性金属粉に非磁性基板とバインダの役割を持たせ、磁性紛を混合し、焼結した、微粒子媒体である。 The conventional magnetic recording tape medium is a fine particle medium in which magnetic powder and a binder are mixed and coated or vapor-deposited on a nonmagnetic substrate. However, the magnetic recording medium of the present invention is a nonmagnetic metal powder coated with a nonmagnetic substrate and a binder. It is a fine particle medium that has the role of, mixed with magnetic powder and sintered.
本発明の磁気記録媒体は、非磁性金属粉と磁性粉を混合・焼結し、これ自体を形状加工を施して作製する。非磁性金属粉として、形状加工を施しやすい、５００℃程度以上の融点をもつ金属、例えば銅またはアルミを用い、磁性粉として安価なコバルト被着ガンマフェライトを用いる。これらの材料を用いることで４００℃程度の高温でも記録情報を保持できる磁気記録媒体を作製することができる。 The magnetic recording medium of the present invention is produced by mixing and sintering a nonmagnetic metal powder and a magnetic powder, and subjecting itself to shape processing. As the non-magnetic metal powder, a metal having a melting point of about 500 ° C. or more, for example, copper or aluminum, which is easy to perform shape processing, is used, and inexpensive cobalt-coated gamma ferrite is used as the magnetic powder. By using these materials, it is possible to manufacture a magnetic recording medium capable of holding recorded information even at a high temperature of about 400 ° C.
非磁性金属粉と磁性粉は合金化するのではなく、焼結体とすることで磁性粉を粒子状に保ち高い保磁力を確保することができる。 The non-magnetic metal powder and the magnetic powder are not alloyed, but by using a sintered body, the magnetic powder can be maintained in the form of particles to ensure a high coercive force.
磁気記録媒体は、ステープルや画鋲のような形状にし、被装着物に取り付けできるようにする。上述した材料・作製方法により、これまでに試作した磁気記録媒体は形状加工性が良く、優れた磁気特性を有しており、メモリとして用いるには充分である。記録・再生はリング型の電磁誘導型ヘッドを用いた接触型としており、作製した磁気記録媒体は信号の記録および再生が可能であることを確認している。また、接触記録・再生方式で、長さ1インチ当たりに約１７００ビットの情報が記録できることを確認した。記録トラック幅をビット長の１０倍程度とすると、提案の磁気記録媒体の記録容量は一般的な２次元バーコードの約３倍に相当する。さらに、作製した磁気記録媒体の耐環境試験で、加圧・水没・２００℃の環境で1時間保持した後でも記録信号を再生できることを確認しており、今後は更に苛酷な条件での耐環境試験を行うことが望ましい。 The magnetic recording medium is shaped like a staple or a thumbtack so that it can be attached to an object. With the materials and manufacturing methods described above, the magnetic recording media that have been experimentally produced so far have good shape processability and excellent magnetic properties, and are sufficient for use as a memory. Recording / reproduction is a contact type using a ring-type electromagnetic induction head, and it has been confirmed that the produced magnetic recording medium can record and reproduce signals. In addition, it was confirmed that about 1700 bits of information can be recorded per inch by the contact recording / reproducing method. When the recording track width is about 10 times the bit length, the recording capacity of the proposed magnetic recording medium corresponds to about 3 times that of a general two-dimensional barcode. Furthermore, in the environmental resistance test of the manufactured magnetic recording medium, it has been confirmed that the recorded signal can be reproduced even after holding for 1 hour in a pressurized, submerged and 200 ° C environment. It is desirable to conduct a test.
また、本発明で作製した磁気記録媒体の信号再生には、現在は接触型の機構を採用しているが、汎用的な使用および信号再生の簡便性を考慮すると再生機構は非接触型であることが望まれる。そこで、光を用いた再生システムの開発が期待される。具体的には、上述の磁気記録媒体の表面に磁気光学材料である軟磁性イットリウム酸化鉄（ＹＩＧ）をスパッタにより成膜し、Ｋｅｒｒ効果を利用して記録信号の再生を行うことが考えられる。一般に、磁気記録媒体と再生センサの距離が大きくなるに連れて再生分解能は低下する。そこで、磁気記録媒体と再生センサとの間隔が３ｍｍ程度以上の非接触型再生システムの開発が待たれる。 In addition, a contact-type mechanism is currently used for signal reproduction of the magnetic recording medium manufactured by the present invention, but the reproduction mechanism is non-contact type in consideration of general use and signal reproduction simplicity. It is desirable. Therefore, development of a reproduction system using light is expected. Specifically, it is conceivable that soft magnetic yttrium iron oxide (YIG), which is a magneto-optical material, is formed on the surface of the magnetic recording medium by sputtering, and the recorded signal is reproduced using the Kerr effect. In general, the reproduction resolution decreases as the distance between the magnetic recording medium and the reproduction sensor increases. Therefore, development of a non-contact type reproduction system in which the interval between the magnetic recording medium and the reproduction sensor is about 3 mm or more is awaited.
本発明では、公知のディジタル磁気記録方式を採用することができる。記録磁化を保持し十分な再生電圧を得るためには、磁化方向の角型比および保磁力が大きくなければならない。また、商品管理等に必要な記録容量を確保するために、面記録密度を高める必要がある。なお、記録・再生はマルチトラックで行うことも可能である。 In the present invention, a known digital magnetic recording system can be employed. In order to maintain the recording magnetization and obtain a sufficient reproduction voltage, the squareness ratio of the magnetization direction and the coercive force must be large. In addition, it is necessary to increase the surface recording density in order to ensure a recording capacity necessary for merchandise management and the like. Note that recording / playback can also be performed by multitrack.
次に、本発明に係る書き換え可能型磁気記録媒体の実施形態について、図１乃至図１１を参照しながら説明する。 Next, an embodiment of a rewritable magnetic recording medium according to the present invention will be described with reference to FIGS.
図１は平板状の磁気記録媒体の斜視図、図２はＴ字型針状の磁気記録媒体の斜視図、図３はステープル形状の磁気記録媒体の斜視図、図４は平板をコ字状に折り曲げた磁気記録媒体の斜視図、図５は平板のコーナー部に先尖状の脚部を有する磁気記録媒体の斜視図、図６は薄型被装着物にステープル形状の磁気記録媒体を取り付けた場合の説明図、図７は厚型被装着物にステープル形状の磁気記録媒体を取り付けた場合の説明図である。図８は焼結により作成したサンプルを示す図である。図９は保磁力の焼結温度依存性を示す図である。図１０は線記録密度特性を示す図である。図１１は水熱処理前後の再生波形を示す図である。 1 is a perspective view of a flat magnetic recording medium, FIG. 2 is a perspective view of a T-shaped magnetic recording medium, FIG. 3 is a perspective view of a staple-shaped magnetic recording medium, and FIG. 4 is a U-shaped flat plate. FIG. 5 is a perspective view of a magnetic recording medium bent into a flat plate, FIG. 5 is a perspective view of a magnetic recording medium having pointed legs at the corners of a flat plate, and FIG. 6 is a staple-shaped magnetic recording medium attached to a thin attachment. FIG. 7 is an explanatory diagram when a staple-shaped magnetic recording medium is attached to a thick-type attachment. FIG. 8 shows a sample prepared by sintering. FIG. 9 is a diagram showing the dependency of the coercive force on the sintering temperature. FIG. 10 is a diagram showing linear recording density characteristics. FIG. 11 is a diagram showing a reproduction waveform before and after hydrothermal treatment.
実施例に基づいて、詳細に説明する。すなわち、支持体１は、磁性粉と非磁性金属粉を混合・焼結して得られた焼結体を加圧成形加工または切断研磨加工することにより構成され、例えば平板状および針状（釘、画鋲、ステープルのような形状を含む）に加圧成形加工または切断研磨加工したものである。 Based on an Example, it demonstrates in detail. That is, the support 1 is configured by pressing or cutting and polishing a sintered body obtained by mixing and sintering magnetic powder and nonmagnetic metal powder. , Including a shape such as a thumbtack and a staple).
まず、上述した支持体１（支持体１全体が磁気記録媒体となっている）について説明する。支持体１を成す磁気記録媒体は、融点が５００℃程度以上の温度である銅（Ｃｕ）やアルミニウム（Ａｌ）などの非磁性金属の粉体とマグヘマイト（γ―Ｆｅ２Ｏ３）やマグネタイト（Ｆｅ３Ｏ４）などの磁性粉を均一になるように充分に混合し、これらの混合物を所望の形状の圧肉容器に充填した後、押圧力を付加するピストンを前記圧肉容器に係合させた状態下で前進させて加圧し、次のような温度、圧力、焼結時間の条件下で製造される。 First, the above-described support 1 (the entire support 1 is a magnetic recording medium) will be described. The magnetic recording medium constituting the support 1 is made of a nonmagnetic metal powder such as copper (Cu) or aluminum (Al) having a melting point of about 500 ° C. or more, maghemite (γ-Fe 2 O 3 ), magnetite ( The magnetic powder such as Fe 3 O 4 ) is sufficiently mixed so as to be uniform, and after filling the mixture into a compact container of a desired shape, a piston for applying a pressing force is engaged with the compact container. It is made to advance under pressure and pressurize, and is manufactured under the following conditions of temperature, pressure and sintering time.
温度 ： ２００℃〜磁性粉の融点以下の温度
圧力 ： ０．５ＭＰａ〜５００ＭＰａ
焼結時間： ２分〜２０時間
Temperature: 200 ° C. to a temperature below the melting point of the magnetic powder Pressure: 0.5 MPa to 500 MPa
Sintering time: 2 minutes to 20 hours
上記のような加圧・温度・焼結時間の環境下で焼結し、その焼結体を圧延して形状加工することにより所望の形状の支持体１が得られる。支持体１は、上記加圧成形加工に限定するものではなく、切断研磨加工してもよい。なお、本発明のメモリ（磁気記録媒体）の大きさは、厚み１ｍｍ程度以下であり、長さが数ｍｍから数十ｍｍのものとなる。なお、磁性粉としては、マグヘマイト（γ―Ｆｅ２Ｏ３）やマグネタイト（Ｆｅ３Ｏ４）に限定するものではなく、バリウムフェライト（ＢａＦｅ１２Ｏ１９）、ストロンチウムフェライト（ＳｒＦｅ１２Ｏ１９）などの科学的に安定で安価な酸化鉄をベースとした磁性酸化物を使用することができる。なお、本発明のメモリ（磁気記録媒体）の保磁力は３００〜４０００Ｏｅ（エルステッド）である。 The support 1 having a desired shape can be obtained by sintering in the environment of pressure, temperature, and sintering time as described above, rolling the sintered body, and processing the shape. The support 1 is not limited to the above-described pressure forming process, and may be cut and polished. The memory (magnetic recording medium) of the present invention has a thickness of about 1 mm or less and a length of several mm to several tens mm. The magnetic powder is not limited to maghemite (γ-Fe 2 O 3 ) or magnetite (Fe 3 O 4 ), but barium ferrite (BaFe 12 O 19 ), strontium ferrite (SrFe 12 O 19 ), etc. Magnetically stable and inexpensive magnetic oxides based on iron oxide can be used. The coercive force of the memory (magnetic recording medium) of the present invention is 300 to 4000 Oe (Oersted).
実施例に示す磁気記録媒体の製造時は、予め非磁性金属粉、磁性粉、ポリビニルアルコール（ＰＶＡ）などのバインダを少量混合し、加圧成形した後にオーブンなどで焼結し、形状加工することができる。 When manufacturing the magnetic recording medium shown in the examples, a small amount of a binder such as non-magnetic metal powder, magnetic powder, polyvinyl alcohol (PVA), etc. is mixed in advance, press-molded, sintered in an oven, etc., and processed into a shape. Can do.
磁気記録媒体は、非磁性金属粉と磁性粉を混合・焼結し、形状加工を施して作製した。非磁性金属粉として形状加工を施しやすいアルミ（Ａｌ）を用い、磁性粉には安価で磁気記録分野で実績のあるコバルト被着ガンマフェライト（Ｃｏ−γ−Ｆｅ２Ｏ３）を用いた。Ａｌ粉末とＣｏ−γ−Ｆｅ２Ｏ３粉末を体積比９：１となるようにボールミルにより乾式混合し、直径１．５ｃｍの筒状の圧肉容器に充填し、放電プラズマ焼結法により、温度を２００℃から５５０℃とし、焼結時間１０分で焼結した。得られた焼結体を切断・研磨し、サンプルを作製した（図８）。サンプルの厚みは約０．５ｍｍである。磁気特性の測定には試料振動型磁力計、記録特性の測定には記録再生特性評価装置を用いた。 The magnetic recording medium was produced by mixing and sintering nonmagnetic metal powder and magnetic powder and performing shape processing. Aluminum (Al), which is easy to form, is used as the nonmagnetic metal powder, and cobalt-coated gamma ferrite (Co-γ-Fe 2 O 3 ) that is inexpensive and has a proven record in the magnetic recording field is used as the magnetic powder. Al powder and Co-γ-Fe 2 O 3 powder were dry-mixed by a ball mill so as to have a volume ratio of 9: 1, filled into a cylindrical compact wall container having a diameter of 1.5 cm, and by discharge plasma sintering, The temperature was changed from 200 ° C. to 550 ° C., and sintering was performed for 10 minutes. The obtained sintered body was cut and polished to prepare a sample (FIG. 8). The thickness of the sample is about 0.5 mm. A sample vibration magnetometer was used for measuring the magnetic characteristics, and a recording / reproducing characteristic evaluation apparatus was used for measuring the recording characteristics.
図９に面内保磁力の焼結温度依存性を示す。保磁力は焼結温度の上昇とともに増大し、４００℃で約１１００Ｏｅとなり，比較的高い値が得られた。また、更に温度を上げると保磁力は減少した。保磁力の焼結温度依存性は、コバルトがγ−Ｆｅ２Ｏ３中に拡散したためであると考えられる。飽和磁化は焼結温度に依らず、ほぼ一定であった。 FIG. 9 shows the sintering temperature dependence of the in-plane coercivity. The coercive force increased as the sintering temperature increased, reaching about 1100 Oe at 400 ° C., which was a relatively high value. Further, the coercive force decreased as the temperature was further increased. It is considered that the coercive force depends on the sintering temperature because cobalt is diffused into γ-Fe 2 O 3 . The saturation magnetization was almost constant regardless of the sintering temperature.
記録・再生特性測定は、オーディオヘッドを用いて接触記録・再生方式で行った。ヘッド・媒体間の相対速度を１ｍ／ｓｅｃとして、方形波信号を記録した。図１０に１１００Ｏｅの保磁力が得られたサンプルの線記録密度特性を示す。同図から、作製したサンプルは、再生出力が孤立反転の再生出力の５０％になる記録密度であるD５０が約１．７ｋＦＲＰＩ程度の記録能力があることが分かる。このサンプルを１ｃｍ角とし、トラック密度を線密度の１０倍と仮定すると、作製したサンプルの記録容量は一般的な２次元バーコードの約３倍に相当する６ｋＢ程度であると予想される。また、記録・再生システムに信号処理を適用することで更なる大容量化が可能である。 Recording / reproduction characteristics were measured by a contact recording / reproduction method using an audio head. A square wave signal was recorded at a relative speed of 1 m / sec between the head and the medium. FIG. 10 shows the linear recording density characteristics of a sample having a coercive force of 1100 Oe. From the figure, sample prepared is found to D 50 reproduced output is recording density becomes 50% of the reproduction output of isolated pulse is approximately 1.7kFRPI about the recording capacity. Assuming that this sample is 1 cm square and the track density is 10 times the linear density, the recording capacity of the produced sample is expected to be about 6 kB, which is about 3 times that of a general two-dimensional barcode. Further, the capacity can be further increased by applying signal processing to the recording / reproducing system.
１１００Ｏｅの保磁力が得られたサンプルに線密度１ｋＦＲＰＩの信号を記録した後、オートクレーブにより加圧、水中２００℃、1時間の水熱処理を施し、信号の再生を行った。水熱処理前後で得られた再生波形を図１１に示す。同図から水熱処理前後の再生波形にほとんど変化はなく、作製したサンプルは水中２００℃程度の環境下でも記録情報を保持できることが分かる。 A signal having a linear density of 1 kFRPI was recorded on a sample having a coercive force of 1100 Oe, and then the signal was regenerated by pressurizing with an autoclave and hydrothermal treatment in water at 200 ° C. for 1 hour. The reproduction waveforms obtained before and after the hydrothermal treatment are shown in FIG. From the figure, it can be seen that there is almost no change in the reproduced waveform before and after the hydrothermal treatment, and that the produced sample can retain the recorded information even in an environment of about 200 ° C.
なお、上記記載の磁気記録媒体を成す支持体１の形状については、平板状（図１）、Ｔ字型針状（図２）、ステープル形状（図３）、平板をコ字状に折り曲げた形状（図４）平板のコーナー部に先尖状の脚部を有する形状（図５）を述べたが、例えば、図５については、平板のコーナー部ではなく、平板の端部のいかなる箇所に先尖状の脚部を有する形状にしてもよく、例えばコーナー部間やそれ以外の部分に配設してもよい。なお、支持体１の形状は図１乃至図５に限定するものではなく、他のいかなる多様な形状にも適用できる。 As for the shape of the support 1 constituting the magnetic recording medium described above, a flat plate shape (FIG. 1), a T-shaped needle shape (FIG. 2), a staple shape (FIG. 3), and a flat plate were bent into a U shape. Shape (FIG. 4) Although the shape (FIG. 5) which has a pointed leg at the corner of the flat plate has been described, for example, in FIG. 5, not at the corner of the flat plate, but at any place on the end of the flat plate A shape having pointed leg portions may be used, and for example, it may be disposed between corner portions or other portions. Note that the shape of the support 1 is not limited to that shown in FIGS. 1 to 5 and can be applied to any other various shapes.
上記のように磁気記録媒体そのものを支持体１を被装着物（製品）５などに取り付ける場合には、図６や図７に示すように、専用の装置を使って支持体１を被装着物５に打ち込んで取り付けることができる。なお、図１に示すような平板形状のものを使用する場合には、例えば被装着物５にドリルなどで穴を開け、紐やワイヤなどで結んでもよいが、端部をステープルなどで留めることもできる。 When the support 1 is attached to the attachment (product) 5 or the like as described above, the support 1 is attached to the attachment using a dedicated device as shown in FIGS. 5 can be installed. In the case of using a flat plate as shown in FIG. 1, for example, a hole or the like may be drilled in the attachment 5 and tied with a string or a wire, but the end is fastened with staples or the like. You can also.
また、支持体１の表面には、厚みが１００μｍ以下となるように酸化防止用樹脂などを噴霧または塗布するとよい。なお、記録および再生を行う場合には、電磁誘導型ヘッドを複数備えたマルチトラックの記録装置や再生装置を用いることができる。また、再生には、磁気抵抗効果型ヘッドを用いることもできる。 In addition, an antioxidant resin or the like may be sprayed or applied on the surface of the support 1 so that the thickness becomes 100 μm or less. When recording and reproduction are performed, a multitrack recording apparatus or reproducing apparatus including a plurality of electromagnetic induction heads can be used. A magnetoresistive head can also be used for reproduction.
１ 支持体
２ 被装着物（製品）
1 Support 2 Attachment object (product)
Claims (5)
5. The magnetic recording medium according to claim 2, wherein an antioxidant film is provided on the surface of the support.
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| KR20170002946A (en) | 2015-06-30 | 2017-01-09 | 삼성전기주식회사 | Magnetic composite and method of manufacturing the same |
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| KR20170002946A (en) | 2015-06-30 | 2017-01-09 | 삼성전기주식회사 | Magnetic composite and method of manufacturing the same |
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