JPH02308418A - Magnetic card - Google Patents
Magnetic cardInfo
- Publication number
- JPH02308418A JPH02308418A JP12981389A JP12981389A JPH02308418A JP H02308418 A JPH02308418 A JP H02308418A JP 12981389 A JP12981389 A JP 12981389A JP 12981389 A JP12981389 A JP 12981389A JP H02308418 A JPH02308418 A JP H02308418A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- film
- card
- low
- permeability
- 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.)
- Pending
Links
- 230000035699 permeability Effects 0.000 claims abstract description 40
- 230000001681 protective effect Effects 0.000 claims abstract description 36
- 239000000758 substrate Substances 0.000 claims abstract description 13
- 230000004907 flux Effects 0.000 abstract description 33
- 230000005415 magnetization Effects 0.000 abstract description 4
- 230000007423 decrease Effects 0.000 abstract description 3
- 230000000149 penetrating effect Effects 0.000 abstract 2
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 238000010030 laminating Methods 0.000 abstract 1
- 239000000696 magnetic material Substances 0.000 description 6
- 239000011888 foil Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 229910000889 permalloy Inorganic materials 0.000 description 3
- 229920000728 polyester Polymers 0.000 description 3
- 229910000702 sendust Inorganic materials 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は基板上に磁性膜を設け、磁気により記録再生
を行う磁気カード、特に磁性膜の片面を低透磁率膜で覆
い、かつこれを軟磁性材料膜で覆った磁気カードに関す
るものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a magnetic card in which a magnetic film is provided on a substrate and performs recording and reproduction using magnetism, in particular, a magnetic card in which one side of the magnetic film is covered with a low magnetic permeability film; This invention relates to a magnetic card covered with a soft magnetic material film.
第３図は従来の磁気カード°の一部の断面図である。図
において、（１）は磁気カードで、ポリエステル等の基
板（２）上に、磁気記録再生可能な磁性体からなる磁性
媒体膜（３）が積層されている。このような従来の磁気
カード（１）は、基板（２）上に磁性媒体膜（３）を設
けた構造であるため、磁気記録内容は、一般に市販され
ている磁気記録再生器でも読取りが可能である。このた
めカードの偽造、悪用等の防犯上の観点から、通常の磁
気記録再生器での読取り、書込みが困難な第４図の磁気
カードが考案された。FIG. 3 is a sectional view of a part of a conventional magnetic card. In the figure, (1) is a magnetic card, in which a magnetic medium film (3) made of a magnetic material capable of magnetic recording and reproduction is laminated on a substrate (2) of polyester or the like. Since such a conventional magnetic card (1) has a structure in which a magnetic medium film (3) is provided on a substrate (2), the magnetically recorded contents can be read by a generally commercially available magnetic recording player. It is. Therefore, from the viewpoint of crime prevention such as counterfeiting and misuse of the card, the magnetic card shown in FIG. 4 was devised, which is difficult to read and write with a normal magnetic recording/reproducing device.
第４図は例えば実公昭５８−５０４９４号に示された従
来の磁気記録再生可能な磁気カードの断面図である。図
において、（４）、（５）は小さい保磁力と高い透磁率
を有する軟磁性体から成る磁性保護膜であり、基板（２
）と磁性媒体膜（３）の間、および磁性媒体膜（３）の
上面に設けられている。FIG. 4 is a cross-sectional view of a conventional magnetic card capable of magnetic recording and reproduction, as shown in, for example, Japanese Utility Model Publication No. 58-50494. In the figure, (4) and (5) are magnetic protective films made of a soft magnetic material with small coercive force and high magnetic permeability.
) and the magnetic medium film (3), and on the upper surface of the magnetic medium film (3).
このような従来の磁気カード（１）においては、磁性保
護膜（４）、（５）のＦａ−Ｎｉ系合金パーマロイある
いはＦｅ−３ｉ−ＡＱ系合金センダスト等高透磁率磁性
材料を用いて、磁性保護膜（４）、（５）の磁気抵抗を
小さくすることにより、磁性媒体膜（３）からの洩れ磁
束が磁性保護膜（４）、 （５）内を流れるため、カー
ド（１）からの洩れ磁束を少なくすることができる。こ
れにより従来の洩れ磁束を拾う磁気ヘッドによる読取り
を困難にし、かつ従来の磁気ヘッドによる記録用磁束も
磁性保護膜（４）、（５）に流れてしまうため、書込み
も困難となる。In such a conventional magnetic card (1), the magnetic protection films (4) and (5) are made of a high magnetic permeability magnetic material such as Fa-Ni alloy permalloy or Fe-3i-AQ alloy sendust. By reducing the magnetic resistance of the protective films (4) and (5), leakage magnetic flux from the magnetic medium film (3) flows through the magnetic protective films (4) and (5), thereby reducing the magnetic flux from the card (1). Leakage magnetic flux can be reduced. This makes it difficult to read with a conventional magnetic head that picks up leakage magnetic flux, and also makes writing difficult because the recording magnetic flux by the conventional magnetic head also flows to the magnetic protective films (4) and (5).
従来の磁気カードは以上のように構成されているため、
磁性媒体膜の飽和磁化の大きさの増加に伴って、磁気カ
ード外への洩れ磁束を少なくするために、磁性保護膜を
厚くしなくてはならなかった。しかし、磁性保護膜の厚
みの増加はそれを流れる磁束磁路の磁気抵抗を下げるの
で、書込み、読取りのための磁束の多くが磁性保護膜に
流れて記録再生を困難とし、一層の磁気ヘッドの磁束密
度の増大を必要とするという問題点があった。Conventional magnetic cards are structured as described above, so
As the saturation magnetization of the magnetic medium film increases, the thickness of the magnetic protective film has to be increased in order to reduce leakage of magnetic flux to the outside of the magnetic card. However, an increase in the thickness of the magnetic protective film lowers the magnetic resistance of the magnetic flux path flowing through it, so much of the magnetic flux for writing and reading flows into the magnetic protective film, making recording and reproducing difficult. There was a problem in that it required an increase in magnetic flux density.
一方、高信頼性磁気カードに要求されている高保磁力磁
性媒体膜の記録には高磁束密度が必要で、磁気ヘッドか
らの書込み磁束を有効に利用するためには磁性保護膜の
薄膜化が必要であるが、これは磁性保護膜内の磁気抵抗
を増大させ、磁気カード外への洩れ磁束を増加させるこ
とになり、防犯上および他の磁気媒体への悪影響が生じ
るなどの問題点がある。On the other hand, high magnetic flux density is required for recording on the high coercive force magnetic media film required for highly reliable magnetic cards, and in order to effectively utilize the write magnetic flux from the magnetic head, it is necessary to make the magnetic protective film thinner. However, this increases the magnetic resistance within the magnetic protective film and increases leakage of magnetic flux to the outside of the magnetic card, which poses problems in terms of crime prevention and adverse effects on other magnetic media.
この発明は上記のような問題点を解消するためになされ
たもので、磁性保護膜の厚みを増すことなく、磁気カー
ド外への漏洩磁束を低減できる磁気カードを得ることを
目的とする。This invention was made to solve the above-mentioned problems, and an object thereof is to obtain a magnetic card that can reduce leakage magnetic flux to the outside of the magnetic card without increasing the thickness of the magnetic protective film.
本発明の磁気カードは、磁気記録再生可能な磁性媒体膜
と、透磁率が低い低透磁率膜と、保磁力が小さくかつ透
磁率の高い磁性保護膜と、基板とから構成されたもので
ある。The magnetic card of the present invention is composed of a magnetic medium film capable of magnetic recording and reproduction, a low magnetic permeability film with low magnetic permeability, a magnetic protective film with low coercive force and high magnetic permeability, and a substrate. .
本発明では磁性媒体膜と磁気カード表面側の磁性保護膜
との間に低透磁率膜を挟むことにより、高磁気抵抗層を
形成するのが好ましい。In the present invention, it is preferable to form a high magnetoresistive layer by sandwiching a low magnetic permeability film between the magnetic medium film and the magnetic protective film on the surface side of the magnetic card.
この場合、記録再生を行う磁性媒体膜の片面に低透磁率
の膜を設け、これを保磁力が小さくかつ透磁率が高い磁
性保護膜で挟み、低透磁率膜と基板とが磁性媒体膜を挟
むように、基板上に配置することができる。低透磁率膜
としては、エポキシ、ポリエステル等の非磁性高分子化
合物、またはアルミニウム箔、貴金属箔を用いることが
できる。In this case, a low magnetic permeability film is provided on one side of the magnetic media film that performs recording and reproduction, and this is sandwiched between magnetic protective films with low coercive force and high magnetic permeability, so that the low magnetic permeability film and the substrate cover the magnetic media film. They can be placed on the substrate so as to be sandwiched between them. As the low magnetic permeability film, a nonmagnetic polymer compound such as epoxy or polyester, aluminum foil, or noble metal foil can be used.
従来の磁気カードは、磁性保護膜にＦｅ−Ｎｉ系合金パ
ーマロイあるいはＦｅ−５ｉ−Ａ＋Ｑ系合金センダスト
等高透磁率磁性材料を用い、磁性保護膜の磁気抵抗を小
さくして、磁性媒体膜からの洩れ磁束の多くを磁性保護
膜に流すようにしていたが、本発明の磁気カードでは、
磁性媒体膜とカード表面側の磁性保護膜との間に新たに
低透磁率膜を設けることにより、磁性媒体膜と低透磁率
膜および磁性保護膜を貫く磁束経路の磁気抵抗を、磁性
媒体膜とカード基板に面した磁性保護膜を貫く磁束経路
の磁気抵抗に対して高くする。これにより磁気カード表
面側への磁束址を、磁気カード内側への磁束斌に較べて
低減させ、磁気カード表面からの磁束の漏洩を低減させ
ることができる。このため磁束が主にこの経路で貫く状
態では、低保磁力膜は高磁気抵抗膜となるが、記録再生
時は磁性保護膜を磁気飽和させるため、磁性媒体膜の記
録再生時、低保磁力膜は高磁気抵抗膜とならず、かつ当
該膜の飽和磁化が７４％さければ記録再生の磁束が低透
磁率膜内に漏洩することはなく、磁気記録再生に影響を
与えない。Conventional magnetic cards use high magnetic permeability magnetic materials such as Fe-Ni alloy permalloy or Fe-5i-A+Q alloy sendust for the magnetic protective film, and reduce the magnetic resistance of the magnetic protective film to prevent the magnetic media film from absorbing the magnetic material. Most of the leakage magnetic flux was directed to the magnetic protective film, but in the magnetic card of the present invention,
By newly providing a low magnetic permeability film between the magnetic medium film and the magnetic protective film on the card surface side, the magnetic resistance of the magnetic flux path that passes through the magnetic medium film, low magnetic permeability film, and magnetic protective film can be reduced. and the magnetic resistance of the magnetic flux path passing through the magnetic protective film facing the card substrate. As a result, the magnetic flux flowing toward the surface of the magnetic card can be reduced compared to the magnetic flux flowing toward the inside of the magnetic card, and leakage of magnetic flux from the surface of the magnetic card can be reduced. Therefore, when the magnetic flux mainly penetrates through this path, the low coercive force film becomes a high magnetoresistance film, but since the magnetic protective film is magnetically saturated during recording and reproducing, the magnetic medium film has a low coercive force during recording and reproducing. If the film is not a high magnetoresistance film and the saturation magnetization of the film is less than 74%, magnetic flux for recording and reproduction will not leak into the low magnetic permeability film and will not affect magnetic recording and reproduction.
以下、この発明の一実施例を図について説明する。第１
図は本発明に係わる磁気カードの一部の断面図、第２図
はそのＡ部の拡大断面図である。An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view of a part of the magnetic card according to the present invention, and FIG. 2 is an enlarged sectional view of part A thereof.
図において、第３図および第４図と同一符号は同一また
は相当部分を示す。（６）は低透磁率膜、磁性媒体膜（
３）に示された矢印ｘ、ｙは磁性媒体膜（３）内の磁化
の方向、破線Ｂは磁気経路（磁路）を示している。In the figure, the same reference numerals as in FIGS. 3 and 4 indicate the same or corresponding parts. (6) is a low magnetic permeability film, a magnetic medium film (
The arrows x and y shown in 3) indicate the direction of magnetization within the magnetic medium film (3), and the broken line B indicates the magnetic path (magnetic path).
磁気カード（１）は、記録再生を行う磁性媒体膜（３）
の上面に低透磁率膜（６）を積層し、これらを保磁力が
小さく、かつ透磁率が高い磁性保護膜（４）、（５）で
挟み、低透磁率膜（６）と基板（２）とが、磁性媒体膜
（３）を挟むように基板（２）上に配置されている。The magnetic card (1) is a magnetic medium film (3) that performs recording and reproduction.
A low magnetic permeability film (6) is laminated on the upper surface of the substrate, and these are sandwiched between magnetic protective films (4) and (5) having low coercive force and high magnetic permeability. ) are arranged on the substrate (2) so as to sandwich the magnetic medium film (3).
以下、低透磁率膜（６）の機能を具体的な形状、サイズ
を用いて説明する。Hereinafter, the function of the low magnetic permeability film (6) will be explained using a specific shape and size.
第２図に示された磁束経路Ｂに沿った磁気抵抗は単純化
して次のように見積もることができる。The magnetic resistance along the magnetic flux path B shown in FIG. 2 can be simply estimated as follows.
磁気抵抗（Ｒ）は磁路長（Ｑ）、断面積（Ｓ）および透
磁率（μ）を用いてＲ＝ｌ（Ｓ・μ）で表されることか
ら、図中、ａ工→ａ２における経路の磁気抵抗（Ｒａ１
→ａｚ）は、
Ｒａ１→ａｚ＝Ｑｏ／（Ｓｏ’μ（１）＋ ２−Ｑ１／
Ｃ８１・μｍ）である。Magnetic resistance (R) is expressed as R=l(S・μ) using magnetic path length (Q), cross-sectional area (S), and magnetic permeability (μ), so in the figure, from a to a2 Path magnetic resistance (Ra1
→az) is Ra1→az=Qo/(So'μ(1)+2-Q1/
C81 μm).
ただし、Ｑｏ、Ｑｌはそれぞれ磁性保護膜（４）、（５
）。However, Qo and Ql are magnetic protective films (4) and (5), respectively.
).
低透磁率膜（６）における磁路長、Ｓｏ、Ｓ工はそれぞ
れ磁性保護膜（４）、（５）、低透磁率膜（６）におけ
る磁路に垂直な断面積、μ。、μｍはそれぞれ磁性保護
膜（４）、（５）、低透磁率膜（６）における透磁率で
ある。The magnetic path lengths So and S in the low magnetic permeability film (6) are the cross-sectional area perpendicular to the magnetic path in the magnetic protective films (4) and (5) and the low magnetic permeability film (6), μ, respectively. , μm are the magnetic permeability of the magnetic protective films (4), (5) and the low magnetic permeability film (6), respectively.
磁気カードにおける代表的値
Ｑ ｏ＝２００μｍ
５ｏ＝５μｍ Ｘ２．５ｎ＋ｍ’
μ。” ＝ １００００
Ｑ１＝１μｍ
Ｓ 、 ＝ １００ ｐ ｍｄＸ ２．５ｍｍ’μど＝
１
を用いれば、磁性保護膜内（Ｒ（１）と低透磁率膜内（
Ｒ４）における磁気抵抗の比は
Ｒ１／Ｒ，＝５
となる。Typical value Q for magnetic cards o=200μm 5o=5μm X2.5n+m'μ. ” = 10000 Q1 = 1 μm S, = 100 p mdX 2.5 mm' μ =
1, the inside of the magnetic protective film (R(1)) and the low magnetic permeability film (
The ratio of magnetoresistance in R4) is R1/R,=5.
ただし、Ｒ０＝Ｑ０／（Ｓｏ・μ。）、Ｒよ＝２・Ｑ工
／（Ｓｌ・μ、）、かつμ。′１μｍ′はμ。、μｍの
比透磁率である。However, R0=Q0/(So・μ.), Ryo=2・Qk/(Sl・μ,), and μ. '1μm' is μ. , the relative magnetic permeability in μm.
この見積りは磁性媒体膜（３）と磁性保護膜（５）との
間に僅かな低透磁率膜（６）を挟むことにより、磁路の
磁気抵抗を容易に増大させることができることを示す。This estimate shows that the magnetic resistance of the magnetic path can be easily increased by sandwiching a small amount of low magnetic permeability film (6) between the magnetic medium film (3) and the magnetic protective film (5).
従って、第３図のような低透磁率膜（６）を有しない従
来の磁気カード（１）に対して、これに前記のような低
透磁率膜（６）を設けた第１図の磁気カード（１）では
、磁性媒体膜（３）の磁気カード（１）表面側の磁気抵
抗が内面側の磁気抵抗に較べて高くなり、これに伴って
カード（１）表面側への総磁束量が内面側に較べ減少す
る。この場合、磁性保護膜（５）のみの磁気抵抗は低透
磁率膜（６）の有無にかかわらず一定であるため、磁性
媒体膜（３）のカード（１）表面側へ磁束の減少は磁性
保護膜（５）からのカード（１）表面外への磁束の漏洩
が低減されることを示している。Therefore, in contrast to the conventional magnetic card (1) which does not have a low magnetic permeability film (6) as shown in Fig. 3, the magnetic card shown in Fig. 1 which has a low magnetic permeability film (6) as described above is used. In the card (1), the magnetic resistance on the front side of the magnetic card (1) of the magnetic medium film (3) is higher than the magnetic resistance on the inner side, and as a result, the total amount of magnetic flux toward the front side of the card (1) increases. decreases compared to the inner side. In this case, since the magnetic resistance of only the magnetic protective film (5) is constant regardless of the presence or absence of the low magnetic permeability film (6), the decrease in magnetic flux toward the card (1) surface side of the magnetic medium film (3) is due to the magnetic This shows that leakage of magnetic flux from the protective film (5) to the outside of the surface of the card (1) is reduced.
これに対してカード（１）内面側への磁束は増加するが
、カード（１）の基板（２）は２００μｍ程度の厚みを
持つためカード（１）裏面からの漏洩磁束の増加は磁性
媒体膜（３）側はど問題とならない。On the other hand, the magnetic flux toward the inner surface of the card (1) increases, but since the substrate (2) of the card (1) has a thickness of about 200 μm, the increase in leakage magnetic flux from the back surface of the card (1) is due to the magnetic media film. (3) It doesn't matter which side.
なお、低透磁率膜（６）は磁気的にはエポキシ樹脂、ポ
リエステル等の非磁性高゛分子化合物が望ましいが、静
電気防止のために導電性でパーマロイ、センダスト等に
較べ充分に低い透磁率を有するアルミニウム箔、貴金属
箔等を用いてもよい。The low magnetic permeability film (6) is preferably made of a non-magnetic polymer compound such as epoxy resin or polyester from a magnetic point of view, but in order to prevent static electricity, it should be conductive and have a sufficiently lower magnetic permeability than permalloy, sendust, etc. Aluminum foil, noble metal foil, or the like may also be used.
以上のように、この発明によれば、磁性媒体膜と磁性保
護膜の間に低透磁率膜を挟むことにより、磁性保護膜の
厚みを増加させることなく、磁気カードからの洩れ磁束
を低減させる効果がある。As described above, according to the present invention, by sandwiching the low magnetic permeability film between the magnetic medium film and the magnetic protective film, leakage magnetic flux from the magnetic card can be reduced without increasing the thickness of the magnetic protective film. effective.
第１図は実施例の磁気カードの一部の断面図、第２図は
そのＡ部の拡大断面図、第３図および第４図は従来の磁
気カードの一部の断面図である。
各図中、同一符号は同一または相当部分を示し、（１）
は磁気カード、（２）は基板、（３）は磁性媒体膜、（
４）、（５）は磁性保護膜、（６）は低透磁率膜である
。FIG. 1 is a sectional view of a portion of the magnetic card of the embodiment, FIG. 2 is an enlarged sectional view of part A thereof, and FIGS. 3 and 4 are sectional views of a portion of a conventional magnetic card. In each figure, the same reference numerals indicate the same or corresponding parts, (1)
is a magnetic card, (2) is a substrate, (3) is a magnetic medium film, (
4) and (5) are magnetic protective films, and (6) is a low magnetic permeability film.
Claims (1)
低透磁率膜と、保磁力が小さくかつ透磁率の高い磁性保
護膜と、基板とから構成されたことを特徴とする磁気カ
ード。(1) A magnetic card comprising a magnetic medium film capable of magnetic recording and reproduction, a low magnetic permeability film with low magnetic permeability, a magnetic protective film with low coercive force and high magnetic permeability, and a substrate. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12981389A JPH02308418A (en) | 1989-05-23 | 1989-05-23 | Magnetic card |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12981389A JPH02308418A (en) | 1989-05-23 | 1989-05-23 | Magnetic card |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02308418A true JPH02308418A (en) | 1990-12-21 |
Family
ID=15018858
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12981389A Pending JPH02308418A (en) | 1989-05-23 | 1989-05-23 | Magnetic card |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02308418A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8397998B1 (en) * | 1999-10-23 | 2013-03-19 | Ultracard, Inc. | Data storage device, apparatus and method for using same |
-
1989
- 1989-05-23 JP JP12981389A patent/JPH02308418A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8397998B1 (en) * | 1999-10-23 | 2013-03-19 | Ultracard, Inc. | Data storage device, apparatus and method for using same |
| US9430727B2 (en) | 1999-10-23 | 2016-08-30 | Ultracard, Inc. | Data storage device, apparatus and method for using same |
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