JPH04201599A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To prevent forgery by sticking or inlaying after cutting off a magnetic pattern by a method wherein the magnetic pattern is arranged within a width capable of reading by a read means. CONSTITUTION:A magnetic pattern 14 and a dummy pattern 16 are aligned within a detection width W, and a length normal to a scanning direction of a magnetic head is made shorter than the detection width W. Though the magnetic pattern 14 is composed of a plurality of patterns, any part thereof is formed by the same magnetic ink and is made the same film thickness and the same width. Therefore, a detection level of each part of the magnetic pattern 14 becomes a same level. Then, in the case where the magnetic pattern 14 is detected by a specified threshold value, if a detected level of each part of the magnetic pattern 14 exceeds the threshold value even slightly, the magnetic pattern 14 can be detected. Forgery by cutting the magnetic pattern 14 crosswise can be prevented thereby.

Description

TECHNICAL FIELD The present invention relates to a magnetic recording medium, and more particularly to a magnetic recording medium that is difficult to forge by cutting and pasting a part of the magnetic pattern of a prepaid magnetic card.

BACKGROUND ART Conventionally, there have been cards with improved security in which a magnetic pattern for authenticity determination, such as a magnetic barcode, is formed on a part of a magnetic card, and the authenticity of the card is determined by reading this with a magnetic head. Are known.

In such a magnetic card, a magnetic pattern made of a magnetic material and a non-magnetic dummy pattern made of a non-magnetic material are formed as patterns for authenticity determination.

In the above magnetic pattern, in order to maintain positional accuracy when read by the magnetic head, the width of the magnetic pattern, that is, the length in the direction perpendicular to the reading direction of the magnetic head, is formed to be longer than the detection width of the magnetic head. . Moreover, a large margin is set for the threshold value of the detection level based on reading by the magnetic head in order to reduce reading errors.

Therefore, since the width of the magnetic pattern is wider than the detection width of the magnetic head, for example, the magnetic pattern of one magnetic card can be cut into multiple parts in the width direction, and each part can be attached to another card base material. By pasting, 1
There have been problems in which a single magnetic card is forged into multiple magnetic cards, and a low-value card is forged into a high-value card.

Purpose An object of the present invention is to provide a magnetic recording medium that can effectively prevent counterfeiting by cutting out and pasting or fitting a magnetic pattern as described above.

DISCLOSURE OF THE INVENTION According to the present invention, in a magnetic recording medium that has a magnetic pattern made of a magnetic material and a dummy pattern made of a non-magnetic material, and whose authenticity is determined by reading the magnetic pattern, the magnetic pattern is read by a reading means. It is placed within a readable width.

DESCRIPTION OF EMBODIMENTS Next, embodiments of a magnetic recording medium according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a magnetic card. As shown in the figure, a magnetic card 10
has a magnetic pattern 14 and a dummy pattern 16 on a card base material 12. The card base material 12 is a normal ID
Like the card, it is made of plastic material, such as 188 micron or 250 micron polyethylene terephthalate film. The magnetic pattern 14 is formed, for example, by screen printing magnetic ink containing a magnetic material, and is scanned by a magnetic head of a reader to read out predetermined data, such as the denomination of a prepaid card. The dummy pattern 16 is made of nonmagnetic material. In FIG. 1, in order to distinguish between the magnetic pattern 14 and the dummy pattern 16, the magnetic pattern 14 is shown in black and the dummy pattern 16 is shown in white; however, in reality, the magnetic pattern 14 and the dummy pattern 1 are shown in white.
6 are all formed in the same color. Therefore, they cannot be distinguished by visual recognition.

Although not shown in FIG. 1, the magnetic pattern 14
A silver ink layer may also be formed on the dummy pattern 16 to hide the pattern.

Although not shown, an overcoat layer is usually formed on these layers.

A feature of this card is that the magnetic pattern 14 and the dummy pattern 16 are formed to have a length narrower than the detection width W of the magnetic head. That is, as shown in the figure, the magnetic patterns 14 and 4 and the dummy pattern 16 are arranged in a line within the detection width W, and the length in the direction perpendicular to the scanning direction of the magnetic head is formed to be shorter than the detection width W. ing.

The magnetic pattern 14 is composed of a plurality of patterns, all of which are formed using the same magnetic ink, and in this embodiment, are formed to have the same thickness and width. As a result, the detection level of each part of the magnetic pattern 14 becomes the same level. Therefore, when detecting the magnetic pattern 14 using a predetermined threshold, the magnetic pattern 14 can be detected if the detection level of each portion of the magnetic pattern 14 exceeds the threshold even slightly. Note that different detection outputs may be obtained by changing the thickness of the magnetic pattern 14.

The magnetic patterns 14 need to have approximately the same width in order to equalize the output level, but there are no restrictions on the length.

The dummy pattern 16 does not have to have the same width and length as the magnetic pattern.

Detection of the magnetic pattern 14 is performed based on the level of detection output depending on the position of the pattern from the card edge, the width of the pattern in the magnetic head running direction, and the thickness of the pattern. That is, a magnetic pattern is scanned by a magnetic head set at a predetermined distance from the edge of the card, a detection voltage corresponding to the magnetic pattern is obtained from a detection coil of the magnetic head, the pattern is recognized, and the authenticity of the card is determined. Determine.

For example, a magnetic pattern 14 as shown in FIG. 7(a)
From this, a detected voltage as shown in FIG. 7(b) is obtained.

According to this magnetic card, the magnetic pattern 14 and the dummy pattern 16 are arranged in a line within the detection width W, and the length in the direction perpendicular to the scanning direction of the magnetic head is formed to be shorter than the detection width W. Moreover, when these patterns are read by a magnetic head, the output is set to a reading detection level, that is, a level that slightly exceeds a threshold value at which the patterns can be detected. Therefore, these patterns are detected as patterns by being read across the entire width direction. Therefore, it is difficult to forge it by cutting it into multiple parts in the width direction.

In order to clarify the features of the above embodiment, it will be explained in comparison with a conventional card.

FIG. 4 shows a conventional magnetic card.

As shown in the figure, in the conventional magnetic card,
The magnetic pattern 14 and the dummy pattern 16 have a detection width W
It is formed sufficiently wider than the For example, as shown in FIG. 5, the width is three times the detection width W. Therefore, when attempting to make a forgery, the magnetic pattern 14 and the dummy pattern 16, which are formed to have a width three times the detection width W shown in FIG. By pasting it on another card base material as shown in the figure, three cards can be made. In this way, three magnetic cards can be counterfeited using one magnetic card. Therefore, for example, a high-value card can be counterfeited by pasting the magnetic pattern 14 and dummy pattern 16 cut out from a high-value prepaid card onto a low-value prepaid card.

According to the card of the present invention, as described above, the length of the magnetic pattern 14 and the dummy pattern 16 in the direction perpendicular to the scanning direction of the magnetic head is shorter than the detection width W,
The output level is also set to a level that slightly exceeds the threshold for pattern detection. Therefore, due to its short length in the width direction, it is difficult to cut it into multiple parts in the width direction like the conventional cards mentioned above, and even if you try to forge a card using each cut part, the cut The read output obtained from each part is below the detection level.
This makes it impossible to detect the magnetic pattern, so it cannot be counterfeited. Furthermore, since the magnetic pattern is formed narrower than the detection width W, when the card is read by a magnetic head, the authenticity of the card is determined based on the output obtained by reading the entire magnetic pattern. Therefore, when setting the output from these magnetic patterns to slightly exceed the detectable threshold, it is easy to set a margin that takes into account reading errors.

FIG. 2 shows another embodiment in which the present invention is applied to a magnetic card. In the example shown in the figure, magnetic patterns 14 and dummy patterns 16 are arranged in a staggered manner. That is, the magnetic pattern 14 and the dummy pattern 16 are arranged within the detection width W with appropriate variations in the width direction.

Also in this embodiment, the magnetic pattern 14 and the dummy pattern 16 are each formed to have a length narrower than the detection width W of the magnetic head, and these patterns are arranged in a staggered manner.

Therefore, when read by the magnetic head, the magnetic pattern 14 is read over the entire width direction.

In the case of this card, the magnetic patterns 14 and the dummy patterns 16 are arranged in a staggered pattern, so if you try to forge multiple cards by cutting these patterns into multiple parts in the width direction, the cut patterns will be cut off. A part of an object's original pattern is missing, resulting in a pattern that is different from the original pattern. Therefore, counterfeiting is more difficult compared to the previous embodiments.

FIG. 3 shows still another embodiment in which the present invention is applied to a magnetic card. In the example shown in the same figure, the magnetic patterns 14 and dummy patterns 16 are arranged in a staggered manner similar to the embodiment shown in FIG. 2, and the magnetic patterns 14 and dummy patterns 16 are also formed outside the detection width W. has been done. In this card, the portion read and detected by the magnetic head is limited to the magnetic pattern 14 within the detection width W, or the magnetic pattern 14 provided outside the detection width W and the dummy pattern 16 are within the detection width W. Same as magnetic pattern 14 and dummy pattern 16
Because it is colored, it can camouflage people who try to counterfeit it. For example, if a person attempting to counterfeit cuts these patterns in the width direction, the magnetic pattern 14 outside the detection width W and the dummy,
Since some patterns consist only of pattern 16, it confuses the person attempting to forge it and makes it difficult to forge it.

In the above embodiment, both the magnetic pattern 14 and the dummy pattern 16 have a rectangular shape, but the shape of these patterns is not limited to a rectangle, and may be, for example, a round shape. Further, in the above embodiment, the widths of the magnetic pattern 14 and the dummy pattern 16 are the same, but these widths may not be uniform. Further, the pitches of these patterns do not need to be constant as in the above embodiments, but can be set as appropriate.

Effects According to the present invention, the magnetic recording medium is arranged within a width in which the magnetic pattern can be read by the reading means. Therefore, there is little risk of forgery by cutting the magnetic pattern in the width direction, effectively preventing forgery and increasing security.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment in which the present invention is applied to a magnetic card, FIGS. 2 and 3 are diagrams showing other embodiments in which the present invention is applied to a magnetic card, and FIG. 4 is a diagram showing a conventional Figures 5 and 6 are diagrams showing a magnetic card; Figures 5 and 6 are diagrams illustrating an example of counterfeiting multiple cards using a conventional magnetic card; 7
FIG. 7(b) is a diagram showing the detection output obtained from the magnetic pattern of FIG. 7(a). Explanation of symbols of main parts 10, , Magnetic card 12, , Card base material 14, , Magnetic pattern 16, , Dummy pattern Wl, Detection width

Claims (1)

[Claims] 1. A magnetic recording medium having a magnetic pattern made of a magnetic material and a dummy pattern made of a non-magnetic material, the authenticity of which is determined by reading the magnetic pattern, wherein the magnetic pattern is read by a reading means. A magnetic recording medium characterized by being arranged within a width that can be read by. 2. The magnetic recording medium according to claim 1, wherein the magnetic patterns are arranged in a staggered manner within a width readable by the reading means. 3. The magnetic recording medium according to claim 1 or 2, wherein the authenticity of the magnetic pattern is determined by reading the entire readable width direction of the magnetic pattern by the reading means. magnetic recording media.