JP2734561B2 - Magnetic recording card - Google Patents
Magnetic recording cardInfo
- Publication number
- JP2734561B2 JP2734561B2 JP63252335A JP25233588A JP2734561B2 JP 2734561 B2 JP2734561 B2 JP 2734561B2 JP 63252335 A JP63252335 A JP 63252335A JP 25233588 A JP25233588 A JP 25233588A JP 2734561 B2 JP2734561 B2 JP 2734561B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic recording
- magnetic
- card
- layer
- recording card
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Description
【発明の詳細な説明】 ＜産業上の利用分野＞ 本発明は、キャッシュカード、クレジットカード、プ
リペイドカード等、カードの表面に磁気記録部が形成さ
れたセキュリティ機能を有する磁気記録カードに関す
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording card such as a cash card, a credit card, a prepaid card, and the like, having a security function in which a magnetic recording portion is formed on a surface of the card.
＜従来の技術＞ 磁気記録カードは、第１図に示すように塩化ビニル等
の磁気記録カード基材（１）に塗布法あるいは接着法に
より磁気記録部（２）を形成したものである。この磁気
記録カード上の情報は第２図に示されるように磁気記録
部（５）を構成する磁性体の磁化によって保持されてお
り、磁気ヘッド（６）を用いて情報が記録・再生される
構成となっている。<Prior Art> As shown in FIG. 1, a magnetic recording card has a magnetic recording portion (2) formed on a magnetic recording card base material (1) such as vinyl chloride by a coating method or an adhesive method. As shown in FIG. 2, the information on the magnetic recording card is held by the magnetization of the magnetic material constituting the magnetic recording section (5), and the information is recorded / reproduced using the magnetic head (6). It has a configuration.
＜発明が解決しようとする課題＞ 上記従来の磁気記録カードの磁気情報は一般の磁気ヘ
ッドによって記録されているので、市販されている一般
の磁気ヘッドを備えた磁気記録カードリーダ・ライタに
よって記録されている磁気記録情報の読み取りが可能で
ある。これによって不正に得た磁気記録情報をもとに磁
気記録カードが容易に偽造、改ざんされる危険がある。<Problems to be Solved by the Invention> Since the magnetic information of the conventional magnetic recording card is recorded by a general magnetic head, the magnetic information is recorded by a magnetic recording card reader / writer equipped with a commercially available general magnetic head. Magnetic recording information can be read. As a result, there is a risk that the magnetic recording card can be easily forged or falsified based on the magnetic recording information obtained illegally.
＜課題を解決するための手段＞ 上記課題を解決すべくなされた本発明は磁気記録され
た磁気記録部上に、保磁力が磁気記録部の磁性体よりも
小さい軟磁性体によって磁気バーを設け、この磁気バー
のパターンをカード固有の秘密情報として記録すること
である。<Means for Solving the Problems> In order to solve the above-described problems, the present invention provides a magnetic bar on a magnetically recorded magnetic recording unit by using a soft magnetic material having a coercive force smaller than that of the magnetic recording unit. That is, the pattern of the magnetic bar is recorded as secret information unique to the card.
通常の磁気記録の再生では記録磁化によって発生する
漏れ磁界を磁気ヘッドによって読みとっている。本発明
は第３図に示すように磁気記録上部に第２層目として軟
磁性体を含む層（３）と軟磁性体を含まない層（４）を
設けたものである。このとき磁気記録部の磁化された磁
性体層から表面に漏れる磁界の大きさは、軟磁性体を含
む層（３）では含まない層（４）に比較して約２倍の大
きさを持つ。この漏れ磁界の大きさを再生出力電圧の大
きさとして読みとることによって軟磁性体によって形成
された磁気バーの存在を確認し、磁気バーによって記録
された情報を磁気記録出力として読みとる。In normal magnetic recording reproduction, a leakage magnetic field generated by recording magnetization is read by a magnetic head. In the present invention, as shown in FIG. 3, a layer (3) containing a soft magnetic material and a layer (4) containing no soft magnetic material are provided as a second layer on the magnetic recording. At this time, the magnitude of the magnetic field leaking from the magnetized magnetic layer of the magnetic recording portion to the surface is about twice as large as that of the layer (3) containing the soft magnetic material as compared to the layer (4) not containing it. . By reading the magnitude of the leakage magnetic field as the magnitude of the reproduction output voltage, the presence of the magnetic bar formed of the soft magnetic material is confirmed, and the information recorded by the magnetic bar is read as the magnetic recording output.
＜作用＞ 本発明の磁気記録カードを図で説明する。100〜2000
μｍの塩化ビニル、PET等プラスチックスからなる磁気
記録カード基材（１）上にγ−Fe2O3 Ba−Ferrite等の2
00〜3000エスルテッドの保磁力を有する磁性体とバイン
ダーからなる磁性塗料を塗布し、厚さ５〜20μｍのスト
ライプ状磁性層（２）を形成する。さらに、その上に第
２層目としてMn−Zn−Ferrite、Ni−Zn−Ferrite、パー
マロイ等保磁力５〜80エルステッドの軟磁性体を含む磁
性インキによって厚さ５〜20μｍの磁気バーパターン
（３）を形成する。<Operation> The magnetic recording card of the present invention will be described with reference to the drawings. 100-2000
2 μm of γ-Fe 2 O 3 Ba-Ferrite etc. on a magnetic recording card substrate (1) made of plastics such as μm vinyl chloride and PET
A magnetic paint composed of a magnetic substance having a coercive force of 00 to 3000 sludge and a binder is applied to form a stripe-shaped magnetic layer (2) having a thickness of 5 to 20 μm. Further, a magnetic bar pattern having a thickness of 5 to 20 μm is formed thereon as a second layer by using a magnetic ink containing a soft magnetic material having a coercive force of 5 to 80 Oe, such as Mn-Zn-Ferrite, Ni-Zn-Ferrite, and Permalloy. ) Is formed.
このような磁気記録カードの情報記録においては第３
図に示されるように、記録用コイル（８）に電流を印加
し、記録用磁気ヘッドコア（７）によって磁気記録を行
なう。In information recording on such a magnetic recording card, the third
As shown in the figure, a current is applied to the recording coil (8), and magnetic recording is performed by the recording magnetic head core (7).
磁気記録層の上に軟磁性体を含む層を設けた場合と軟
磁性体を含まない層を設けた場合の磁気記録・再生出力
の大きさを第２層を設けなかった場合の出力に対する相
対出力として第４図に示す。第２層目の厚さの変化によ
らず、再出力の大きさは軟磁性体を含む層は含まない層
と比較して約２倍の大きさである。The magnitude of the magnetic recording / reproducing output between the case where the layer containing the soft magnetic material is provided on the magnetic recording layer and the case where the layer containing no soft magnetic material is provided is relative to the output when the second layer is not provided. The output is shown in FIG. Regardless of the change in the thickness of the second layer, the magnitude of the re-output is about twice as large as that of the layer not including the layer containing the soft magnetic material.
本発明を用いた磁気記録カードを再生した時の再生出
力波形を第５図に示す。磁気記録は通常の磁気ヘッドを
用いて再生することができる。第５図において（イ）は
軟磁性体を含む層（３）を設けた部分、および（ロ）は
軟磁性体を含まない層（４）を設けた部分の出力波形で
ある。再生出力電圧は第２層目として軟磁性体を含む層
（３）を設けた部分は、軟磁性体を含まない層（４）を
設けた部分に比較して約２倍となっている。第２層目が
軟磁性体を含む層（３）であるか、軟磁性体を含まない
層（４）であるかによって再生出力の大きさはブロック
化される。即ち出力電圧の検出を電子回路的に処理する
ことによって通常の磁気記録と磁気バーによる記録を分
離することが可能である。FIG. 5 shows a reproduction output waveform when reproducing a magnetic recording card using the present invention. Magnetic recording can be reproduced using a normal magnetic head. In FIG. 5, (a) shows an output waveform of a portion provided with a layer (3) containing a soft magnetic material, and (b) shows an output waveform of a portion provided with a layer (4) containing no soft magnetic material. The reproduction output voltage of the portion provided with the layer (3) containing the soft magnetic material as the second layer is about twice as large as the portion provided with the layer (4) containing no soft magnetic material. Depending on whether the second layer is a layer (3) containing a soft magnetic material or a layer (4) not containing a soft magnetic material, the magnitude of the reproduction output is blocked. That is, it is possible to separate normal magnetic recording from recording by a magnetic bar by processing the detection of the output voltage in an electronic circuit.
以上のように、通常の磁気記録と磁気バーパターンに
よる記録が分離可能であり、カード固有の秘密情報を磁
気バーパターンとして記録・再生する事ができる。As described above, normal magnetic recording and recording using a magnetic bar pattern can be separated, and secret information unique to a card can be recorded / reproduced as a magnetic bar pattern.
また、本発明を用いて記録を行った磁気記録カード
は、その再生出力波形を複製記録する事によって偽造さ
れる危険が考えられる。第６図（イ）に本発明を用いて
磁気記録カードの出力波形および第６図（ロ）に複製し
た磁気記録カードの再生出力波形を示す。ここで複製し
た磁気記録カードの磁気記録を再度磁気記録カードに書
き込むと、複製磁気記録カードでは磁気バーパターンと
して記録されていた秘密記録は失われ、再生出力波形は
第６図（ニ）となる。磁気記録を再度磁気記録カードに
書き込むことによって複製磁気記録カードを検出するこ
とが可能である。本発明を磁気記録カードセキュリティ
機能として用いることができる。In addition, a magnetic recording card on which recording has been performed by using the present invention may be counterfeited by duplicating and recording the reproduced output waveform. FIG. 6 (a) shows the output waveform of the magnetic recording card using the present invention and FIG. 6 (b) shows the reproduced output waveform of the copied magnetic recording card. Here, when the magnetic recording of the duplicated magnetic recording card is rewritten on the magnetic recording card, the secret recording recorded as the magnetic bar pattern on the duplicated magnetic recording card is lost, and the reproduced output waveform is as shown in FIG. . By writing the magnetic recording again on the magnetic recording card, it is possible to detect the duplicate magnetic recording card. The present invention can be used as a magnetic recording card security function.
＜実施例＞ 以下本発明の実施例を図面を参照し、詳細に説明す
る。<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.
＜実施例１＞ 第１図は本発明による磁気記録カードの正面図（イ）
および断面図（ロ）である。188μｍのPETからなるカー
ド基材（１）上に第１層目として300エルステッドの保
磁力を有するフェライト、ポリウレタン樹脂およびメチ
ルエチルケトンからなる磁性インキをグラビア法によっ
て塗布し、厚さ15μｍのストライプ状磁気記録部（２）
を形成した。該磁気記録部（２）の飽和磁化は1.96（Ma
xwell/cm2）、残留磁化は0.82（Maxwell/cm2）であっ
た。さらに、該磁気記録部（２）の上に保磁力60エルス
テッドのNi−Zn−フェライト軟磁性体、ポリウレタン樹
脂およびメチルエチルケトンからなる磁性インキをスク
リーン法によって塗布し、厚さ５μｍ、幅2mmの磁気バ
ーパターン（３）を形成した。ポリウレタン樹脂をメチ
ルエチルケトンに溶解させた軟磁性体を含まないインキ
を用い、該磁気バーパターン（３）が形成されていない
部分をスクリーン法によって塗布した。圧ロールにより
プレス加工を行なって表面の形状を整え、磁気記録カー
ドを得た。<First Embodiment> FIG. 1 is a front view of a magnetic recording card according to the present invention (a).
And a sectional view (b). A magnetic ink composed of ferrite, a polyurethane resin and methyl ethyl ketone having a coercive force of 300 Oe is applied as a first layer on a card base material (1) made of PET having a thickness of 188 μm by a gravure method, and a stripe-shaped magnetic recording having a thickness of 15 μm is made. Department (2)
Was formed. The saturation magnetization of the magnetic recording section (2) is 1.96 (Ma
xwell / cm 2 ) and residual magnetization was 0.82 (Maxwell / cm 2 ). Further, a magnetic ink composed of a Ni-Zn-ferrite soft magnetic material having a coercive force of 60 Oersted, a polyurethane resin and methyl ethyl ketone was applied on the magnetic recording portion (2) by a screen method, and a magnetic bar having a thickness of 5 µm and a width of 2 mm was applied. Pattern (3) was formed. A portion where the magnetic bar pattern (3) was not formed was applied by a screen method using an ink not containing a soft magnetic material in which a polyurethane resin was dissolved in methyl ethyl ketone. The surface was adjusted by pressing with a pressure roll to obtain a magnetic recording card.
上記のように作製した磁気記録カードにヘッドギャッ
プ20μｍの磁気ヘッドを用いてヘッド電流45mA（最適電
流）、記録密度200FCIで磁気記録を行なった。Magnetic recording was performed on the magnetic recording card manufactured as described above using a magnetic head having a head gap of 20 μm at a head current of 45 mA (optimal current) and a recording density of 200 FCI.
磁気記録を行なった磁気記録カードの再生出力電圧を
測定し、第２層が軟磁性体を含む層（３）で5.3V、第２
層が軟磁性体を含まない層（４）で2.9V、であった。第
２層が軟磁性体を含む層（３）および第２層が軟磁性体
を含まない層（４）それぞれの再生出力電圧の差、すな
わち磁気バーパターンとして磁気記録カード固有の秘密
情報を記録することができる。The reproduction output voltage of the magnetic recording card on which the magnetic recording was performed was measured, and the second layer was 5.3 V in the layer (3) containing a soft magnetic material.
The layer was 2.9 V in the layer (4) containing no soft magnetic material. The difference between the reproduction output voltages of the layer (3) in which the second layer contains a soft magnetic material and the layer (4) in which the second layer does not contain a soft magnetic material, that is, secret information unique to a magnetic recording card is recorded as a magnetic bar pattern. can do.
＜実施例２＞ 実施例１に示した磁気記録カードと同一構成の磁気記
録カード（Ａ）ならびに、実施例１で用いたのと同様の
磁気記録カード基材上に実施例１で用いたのと同様の磁
気記録部（２）を持つ磁気記録カード（Ｂ）を作製し
た。記録用磁気ヘッドに印加するバイアス電圧および記
録磁気ヘッドの電流を調節する事によって記録磁化の大
きさを制御することにより磁気記録カード（Ａ）の再生
出力波形を磁気記録カード（Ｂ）に記録し、複製磁気記
録カード（Ｂ′）を作製した。<Example 2> A magnetic recording card (A) having the same configuration as the magnetic recording card shown in Example 1 and a magnetic recording card base material similar to that used in Example 1 were used. A magnetic recording card (B) having a magnetic recording portion (2) similar to that described above was produced. The reproduction output waveform of the magnetic recording card (A) is recorded on the magnetic recording card (B) by controlling the magnitude of the recording magnetization by adjusting the bias voltage applied to the recording magnetic head and the current of the recording magnetic head. A duplicate magnetic recording card (B ') was produced.
第６図（イ）に磁気記録カード（Ａ）の再生出力波形
および第６図（ロ）に複製磁気記録カード（Ｂ′）の再
生出力波形を示す。磁気記録カード（Ａ）と複製磁気記
録カード（Ｂ′）の再生出力波形は一致する。FIG. 6 (a) shows the reproduced output waveform of the magnetic recording card (A), and FIG. 6 (b) shows the reproduced output waveform of the duplicate magnetic recording card (B '). The reproduced output waveforms of the magnetic recording card (A) and the duplicate magnetic recording card (B ') match.
磁気記録カード（Ａ）および磁気記録カード（Ｂ′）
の磁気記録の再生出力を実施例１を用いたのと同様な記
録条件で磁気記録カード（Ａ）ならびに複製磁気記録カ
ード（Ｂ′）に重ね書きした再生出力波形を第６図
（ハ）および（ニ）に示す。磁気記録カード（Ａ）の磁
気記録の再生出力を磁気記録カードに重ね書きすると、
磁気記録カード（Ａ）は磁気バーパターンにより第６図
（ハ）に示す出力波形となる。しかし、従来の複製磁気
記録カード（Ｂ′）では本発明によって磁気記録カード
（Ａ）に設けられている磁気バーパターンがないため、
磁気記録カード（Ａ）固有の秘密記録情報は再生されな
い。Magnetic recording card (A) and magnetic recording card (B ')
FIG. 6 (c) shows the reproduction output waveform of the magnetic recording recorded on the magnetic recording card (A) and the duplicate magnetic recording card (B ') overwritten under the same recording conditions as in the first embodiment. (D). When the reproduction output of the magnetic recording of the magnetic recording card (A) is overwritten on the magnetic recording card,
The magnetic recording card (A) has an output waveform shown in FIG. 6C due to the magnetic bar pattern. However, in the conventional duplicate magnetic recording card (B '), there is no magnetic bar pattern provided on the magnetic recording card (A) according to the present invention.
The secret recording information unique to the magnetic recording card (A) is not reproduced.
以上のように磁気バーパターンを持たない複製磁気記
録カードを認識する事が可能であり、本発明によってセ
キュリティ機能を持つ磁気記録カードが実現できる。As described above, a duplicate magnetic recording card having no magnetic bar pattern can be recognized, and a magnetic recording card having a security function can be realized by the present invention.
また、本発明は一般に用いられている磁気ヘッドを利
用可能であり、特殊な磁気ヘッドを必要としない、その
ため現在用いられている磁気記録・再生装置の電子回路
的改良によって本発明を利用することが可能でる。Further, the present invention can utilize a commonly used magnetic head and does not require a special magnetic head. Therefore, the present invention utilizes the present invention by improving an electronic circuit of a magnetic recording / reproducing apparatus currently used. Is possible.
＜発明の効果＞ 本発明により磁気記録カードの磁気記録部上に直接形
成した、あらかじめ設定した情報としての磁気バーパタ
ーンによって秘密情報の記録を行なうことができる。こ
の磁気バーパターンの複製に対して、再生出力を重ね書
きする事によって磁気バーパターンの有無を確認するこ
とができ、セキュリティ機能を負荷した磁気記録カード
が実現できる。<Effect of the Invention> According to the present invention, it is possible to record confidential information by using a magnetic bar pattern as information set directly on a magnetic recording portion of a magnetic recording card. By overwriting the reproduced output with respect to the copy of the magnetic bar pattern, the presence or absence of the magnetic bar pattern can be confirmed, and a magnetic recording card loaded with a security function can be realized.
第１図は本発明を使用する磁気記録カードの正面図
（イ）および断面図（ロ）であり、第２図は従来の磁気
記録カードの磁気記録状態を表わす断面図であり、第３
図は本発明を使用する磁気記録カードの磁気記録状態を
表わす断面図であり、第４図は磁気記録層の上に軟磁性
体を含む層（３）を設けた場合と軟磁性体を含まない層
（４）を設けた場合の磁気記録・再生出力の大きさを第
２層を設けなかった場合の出力に対する相対出力として
示す図であり、第５図は本発明を用いた磁気記録カード
の再生出力波形を示す図であり、第２層として軟磁性体
を含む層（３）を設けた場合（イ）および第２層として
軟磁性体を含まない層（４）を設けた場合（ロ）であ
り、第６図は本発明を用いた磁気記録カードの再生出力
波形（イ）、複製磁気記録カードの再生出力波形
（ロ）、再度磁気記録を行なった磁気記録カードの再生
出力波形（ハ）、再度磁気記録を行なった複製磁気記録
カードの再生出力波形（ニ）であり、第７図は従来の磁
気記録カードの正面図（イ）および断面図（ロ）であ
る。 １……磁気記録カード基材 ２……磁気記録部 ３……軟磁性体を含む層（磁気バー） ４……軟磁性体を含まない層 ５……磁気記録部に記録された通常の磁気記録情報 ６……磁気記録・再生用ヘッド ７……磁気記録・再生用ヘッドコア ８……磁気記録・再生用コイルFIG. 1 is a front view (a) and a sectional view (b) of a magnetic recording card using the present invention. FIG. 2 is a sectional view showing a magnetic recording state of a conventional magnetic recording card.
FIG. 4 is a cross-sectional view showing a magnetic recording state of a magnetic recording card using the present invention. FIG. 4 shows a case where a layer (3) containing a soft magnetic material is provided on a magnetic recording layer and a case where the soft magnetic material is included. FIG. 5 is a diagram showing the magnitude of the magnetic recording / reproducing output when the non-layer (4) is provided as a relative output to the output when the second layer is not provided, and FIG. 5 shows a magnetic recording card using the present invention. FIG. 7 is a diagram showing a reproduction output waveform of a case where a layer (3) containing a soft magnetic material is provided as a second layer (A) and a layer (4) containing no soft magnetic material is provided as a second layer ( FIG. 6 is a reproduction output waveform of a magnetic recording card using the present invention (a), a reproduction output waveform of a duplicate magnetic recording card (b), and a reproduction output waveform of a magnetic recording card on which magnetic recording is performed again. (C) The reproduced output waveform of the duplicate magnetic recording card on which the magnetic recording was performed again (d) , And the FIG. 7 is a front view of a conventional magnetic recording card (a) and a sectional view (b). DESCRIPTION OF SYMBOLS 1 ... Magnetic recording card base material 2 ... Magnetic recording part 3 ... Layer (magnetic bar) containing soft magnetic material 4 ... Layer not containing soft magnetic material 5 ... Normal magnetism recorded on magnetic recording part Recording information 6: Magnetic recording / reproducing head 7: Magnetic recording / reproducing head core 8: Magnetic recording / reproducing coil
Claims (1)
録カードにおいて、保磁力が前記磁気記録部の磁性体よ
りも小さい軟磁性体を含む磁気バーを該磁気記録部上に
カード固有の秘密情報としてパターン状に形成すること
を特徴とする磁気記録カード。In a magnetic recording card having a magnetic recording portion formed on the card surface, a magnetic bar including a soft magnetic material having a coercive force smaller than that of the magnetic recording portion is provided on the magnetic recording portion with a secret bar unique to the card. A magnetic recording card characterized by being formed in a pattern as information.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63252335A JP2734561B2 (en) | 1988-10-06 | 1988-10-06 | Magnetic recording card |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63252335A JP2734561B2 (en) | 1988-10-06 | 1988-10-06 | Magnetic recording card |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0298498A JPH0298498A (en) | 1990-04-10 |
| JP2734561B2 true JP2734561B2 (en) | 1998-03-30 |
Family
ID=17235837
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63252335A Expired - Lifetime JP2734561B2 (en) | 1988-10-06 | 1988-10-06 | Magnetic recording card |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2734561B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2717284B1 (en) * | 1994-03-11 | 1996-04-05 | Thomson Csf | Magnetic card and device for reading this card. |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6133123A (en) * | 1984-07-24 | 1986-02-17 | Shiba Trading Kk | Beautiful hair food for growing and nourishing hair |
-
1988
- 1988-10-06 JP JP63252335A patent/JP2734561B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0298498A (en) | 1990-04-10 |
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