JPH10143807A - Magnetic recording method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic recording method and its device for recording as variable magnetic information by synchronizing with an information recording medium, which is provided with fixed magnetic information consisting of minute recessed and projecting parts, the same magnetic information as the fixed. SOLUTION: Fixed magnetic information, consisting of plural minute recessed and projecting parts arranged along the scanning direction of a magnetic head, which is an information recording part 3 of an information recording medium 1, is read by the magnetic head; and then, by other magnetic head that scans integrally with this magnetic head, the same magnetic information as the fixed is once recorded on a hard magnetic layer in an area other than the information recording part 3 so as to form a temporary track. Then, the magnetic information on the temporary track is read by the magnetic head; using other magnetic head that scans integrally with this magnetic head, the same variable magnetic information as the fixed is synchronized and recorded on the hard magnetic layer of the information recording part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording method and a magnetic recording apparatus, and more particularly, to a magnetic recording method for an information recording medium having an information recording section formed on a substrate such as a card for preventing forgery. And equipment.

[0002]

2. Description of the Related Art Conventionally, in order to prevent forgery of a card such as a prepaid card, information is written at a high recording density to an information recording section composed of a magnetic layer so that recorded information cannot be easily read from the outside. I have to.

However, since the recorded information can be freely rewritten and erased due to the characteristics of the magnetic layer, forgery and falsification are possible. In recent years, it has been highlighted as a major social problem. In particular, since it is now easy to obtain magnetic stripes, it is possible to manufacture similar cards, and to read magnetic information from the magnetic layer exposed on the surface of the information recording medium, or to use magnetic transfer technology. Therefore, there is also a problem that magnetic information can be easily transferred to another magnetic layer.

In order to solve such a problem, an information recording medium in which a magnetic layer constituting an information recording section is composed of a layer containing a magnetic material having a relatively high coercive force and a layer containing a magnetic material having a low coercive force. Is being developed. In this information recording medium, information recorded on a magnetic layer containing a magnetic material having a relatively high coercive force is different from information recorded on a magnetic layer containing a magnetic material having a low coercive force. Cannot be read accurately.

However, the information recording medium as described above can read magnetic information under a normal environment by using a commercially available magnetic recording device. Here, the normal environment means an environment in which temperature, humidity, and the like are not changed. Further, the magnetic layer containing a magnetic material having a relatively high coercive force can be erased and rewritten by a magnetic head under a normal environment by using a specific device. Even if magnetic information is recorded on a magnetic layer containing a material, there has been a problem that forgery and alteration cannot be effectively prevented.

Further, variable magnetic information such as balance information cannot be recorded on a layer made of a low coercivity magnetic material capable of ordinary magnetic recording from the viewpoint of forgery prevention. Although it is possible to store variable magnetic information,
The burden on the terminal is large and not practical.

To prevent forgery of an information recording medium such as a prepaid card, a predetermined magnetic pattern is formed on the information recording medium in advance. This is to determine the authenticity of the card by reading a magnetic pattern formed in advance when used and determining whether a predetermined magnetic output signal is obtained.

For reading such a magnetic pattern,
Usually, a magnetic head wound with two coils is used. A constant current is applied to one of the coils of the magnetic head, and the induced current or voltage induced when the magnetic head scans the magnetic pattern is applied to the other coil. To detect. The induced current is generated according to a change in the magnetic flux of the magnetic head.

On the other hand, as a material constituting the magnetic pattern, for example, a ferromagnetic material is used, and various shapes of the magnetic pattern can be considered. A so-called bar code pattern is generally used. . This magnetic pattern is configured by arranging a plurality of magnetic bars, which are pattern elements, in the width direction thereof, and the width of each magnetic bar constituting the magnetic pattern is one type or two or more types. A magnetic output signal can be obtained by scanning the bar-code-shaped magnetic pattern at a constant speed with the above-described magnetic head in close contact.

As a method for forming the above magnetic pattern, a screen printing method, an offset printing method, a gravure printing method, or the like can be used. These printing methods are advantageous in terms of manufacturing costs.

[0011]

However, pattern formation by the printing method has the following problems due to the characteristics of the printing method.

For example, in the screen printing method, since the number of meshes and the diameter of the screen mesh cannot be ignored,
There is a physical limit to reducing the print line width itself, and there is a disadvantage that the recording density cannot be improved. In addition, as the recording density is increased, the transfer of the ink becomes more unstable, and the printing shape becomes non-uniform due to ink leveling and the like (in addition, the printing film thickness tends to increase as the width increases). There is an inconvenience that the magnetic output and the waveform also become unstable, making it difficult to obtain accurate information. Further, since the same pattern as that of the screen version is duplicated, there is a problem that only certain information is given to the information recording medium and different information cannot be given to each information recording medium.

Further, there is a limit to the forgery prevention effect of an information recording medium such as a prepaid card by forming the magnetic pattern as described above, and a more reliable forgery prevention measure is demanded.

The present invention has been made in view of such circumstances, and the same magnetic information as the above-described fixed magnetic information is recorded on an information recording medium having fixed magnetic information comprising minute irregularities in an information recording section. It is an object of the present invention to provide a magnetic recording method and a magnetic recording apparatus for synchronously recording variable magnetic information.

[0015]

In order to achieve the above object, a magnetic recording method of the present invention comprises a substrate and an information recording section formed on the substrate, wherein the information recording section has at least An information recording medium comprising a magnetic layer having a hard magnetic layer, wherein fixed magnetic information comprising a plurality of fine irregularities arranged in a scanning direction of a magnetic head is recorded on the magnetic layer. A magnetic recording method for synchronously recording the same variable magnetic information as the fixed magnetic information on the magnetic layer, wherein the fixed magnetic information consisting of the irregularities is read by scanning a magnetic head on the information recording unit, At the same time, another magnetic head is scanned integrally with the magnetic head in an area other than the information recording area and on which the hard magnetic layer is formed, and the same magnetic field as the fixed magnetic information read by the magnetic head is read. Emotion Is recorded on the hard magnetic layer to form a provisional track, and a magnetic head is scanned over the provisional track to read magnetic information recorded on the provisional track. A second magnetic head that scans the magnetic head integrally with the magnetic head and records magnetic information read by the magnetic head on the hard magnetic layer;
And a stage.

Further, the magnetic recording method of the present invention further comprises:
The structure includes a third step of erasing magnetic information recorded on the provisional track.

Further, according to the magnetic recording method of the present invention, the magnetic layer of the information recording medium has a soft magnetic layer, and the soft magnetic layer has the irregularities. The configuration is such that the magnetic head is scanned over the information recording section while applying a current.

According to a first aspect of the present invention, there is provided a magnetic recording apparatus comprising: a transport unit for transporting an information recording medium; and a first magnetic head sequentially arranged along a transport direction of the information recording medium by the transport unit. And a second magnetic head unit, wherein the first magnetic head unit includes a reading magnetic head H1 provided at a position for scanning an information recording unit of an information recording medium conveyed by the conveyance unit, and an information recording unit. And a writing magnetic head H2 provided at a position for scanning a portion separated by a predetermined distance from the recording medium. The second magnetic head scans the information recording section of the information recording medium conveyed by the conveying means. And a reading magnetic head H4 provided at a position for scanning the same portion on the information recording medium scanned by the magnetic head H2. And

In the above magnetic recording apparatus, a demagnetizing section is provided downstream of the second magnetic head section in the transport direction of the information recording medium, and the demagnetizing section is scanned by the magnetic heads H2 and H4. Magnetic head H5 provided at a position for scanning the same portion on the information recording medium
And the magnetic head H1 is configured to be a magnetic head capable of bias reading.

According to a second aspect of the present invention, there is provided a magnetic recording apparatus comprising: a transport unit for transporting an information recording medium; and a magnetic head unit disposed on a transport path of the information recording medium by the transport unit. The magnetic head section includes a magnetic head Ha for writing and reading provided at a position for scanning the information recording section of the information recording medium conveyed by the conveying means, and a section separated by a predetermined distance from the information recording section. And a magnetic head Hb for writing / reading provided at a position where the magnetic head Hb is provided.

In the above magnetic recording apparatus, a degaussing section is provided downstream of the magnetic head section in the transport direction of the information recording medium, and the degaussing section is provided on the information recording medium scanned by the magnetic head Hb. The magnetic head Ha for erasing is provided at a position where the same portion is scanned, and the magnetic head Ha is a magnetic head capable of bias reading.

In the present invention as described above, by scanning two magnetic heads integrally on an information recording medium,
Temporary tracks are formed by temporarily recording fixed magnetic information consisting of a plurality of fine irregularities arranged along the scanning direction of the magnetic head of the information recording section on the hard magnetic layer in an area other than the information recording section, Since the magnetic information of the provisional track is recorded on the hard magnetic layer of the information recording unit by scanning the two magnetic heads integrally, the variable magnetic information that is the same as the fixed magnetic information of the information recording medium forms the magnetic layer. The recording is performed in synchronization with the hard magnetic layer.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

First, an information recording medium to be recorded by the magnetic recording method and the magnetic recording apparatus of the present invention will be described by way of an example.

FIG. 1 is a perspective view of a card-shaped information recording medium, and FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and the cross-sectional state is schematically and simplified for easy understanding. It is drawn in.

The information recording medium 1 comprises a substrate 2 and the substrate 2
And an information recording section 3 formed on the information recording section. As shown in FIG. 2, the information recording section 3 includes a magnetic layer 4 including a hard magnetic layer 5 formed on the substrate 2 and a soft magnetic layer 7 formed on the hard magnetic layer 5. The surface of the soft magnetic layer 7 is provided with a plurality of fine irregularities 7a arranged along the scanning direction of the magnetic head, whereby fixed magnetic information is recorded on the magnetic layer 4. .

As described above, the fine irregularities 7a constituting the fixed magnetic information recorded on the soft magnetic layer 7 have a predetermined length in the depth direction of the paper of FIG. 2 (this is shown in FIG. 1). Easy to understand). The concavities and convexities 7a are configured to have at least two or more different types of widths (widths in the scanning direction of the magnetic head) having the same depth of the concave portions (height of the convex portions). The difference in the waveform of the read output due to the difference in the horizontal width can be discriminated into digital signal values of 0 and 1. For example, as shown in FIG. 3, 1 indicates that a set of recesses and protrusions is inserted into one bit at equal intervals, and 0 indicates a recess or double having a width twice as large as 1 in one bit. A convex portion can be formed, and in this case, the magnetic reproduction waveform is as shown in the figure.

The depth (height of the convex portion) of the concave portion of the unevenness 7a is 2 to 30 μm, preferably about 5 to 20 μm.
Its width can be set in the range of about 30 μm to 1 mm. Further, as described later, when the soft magnetic layer 7 is formed by a vacuum evaporation method, a sputtering method, or a plating method, the depth of the concave portion (the height of the convex portion) of the unevenness 7a is 100 to 1.
000 °, preferably about 400 to 600 °.

The fine irregularities 7a include, for example, a method of irradiating a laser beam to a position corresponding to the formation of a concave portion, a method of irradiating an electron beam, destruction by electric discharge, and a routing (engraving) process.

When a laser beam is used, the type of laser to be used, the laser wavelength, the laser power, and the like may be appropriately set in consideration of the material properties of the substrate 2, the line width to be removed, and the like.

As a gas laser, a He-Ne laser, a He-Cd laser, an argon laser (0.48
Rare gas ion laser such as 8 μm continuous oscillation, 0.1 to 20 W); carbon dioxide laser (10.6 μm continuous oscillation, 1
W to 10 kW); a metal vapor laser or the like can be used. As a solid laser, a ruby laser (0.6943 μm pulse oscillation, 10 to 1000 J),
Nd glass laser (1.06 μm pulse oscillation, 10 to 10
1000J), pulsed solid-state laser such as Nd: YAG laser; or ruby laser, Nd glass laser, Nd: YAG laser (continuous oscillation of 1.06 μm,
1 to 200 W), and a continuous excitation solid-state laser such as an Nd: YAlO ₃ laser can be used. As the liquid laser, a dye laser, a Raman laser, a chelate laser, an Nd ³⁺ liquid laser or the like can be used, and as the semiconductor laser, a GaAs diode laser or the like can be used.

Among them, a CO ₂ gas laser having a wavelength of 10.6 μm (output: 0.5 W to 20 W), an Ar gas laser having a wavelength of 0.488 μm (or 0.5145 μm) (output: 0.5 W to 20 W), 1.06 μm
Nd: YAG laser (output: 0.5 W to 20 W) is a preferred example. In addition, if the output of the laser is too high, the accuracy of the concavo-convex pattern will be poor due to damage to the substrate due to high temperature, while if the output is too low,
A sufficient uneven pattern cannot be formed.

Since the fixed magnetic information is recorded by forming the minute unevenness 7a, the magnetic information as the invariable recording can be individual data for each information recording medium.

In the above example, the case where the width of the unevenness 7a is two types is illustrated, but the present invention is not limited to this, and the width of the unevenness 7a may be three or more types.

The hard magnetic layer 5 constituting the magnetic layer 4 is usually
Contains hard magnetic powder and resin binder. Examples of the hard magnetic powder include γ-Fe ₂ O ₃ and Co-coated γ-Fe ₂ O
_{3, Fe 3 O 4, Fe} , Fe-Cr, Fe-Co, Co
-Cr, Co-Ni, Ba ferrite, Sr ferrite, and a magnetic particle such as CrO _2.

The soft magnetic layer 7 constituting the magnetic layer 4 is
When formed by a method of applying a magnetic paint, it usually contains a soft magnetic powder and a resin binder. As the soft magnetic powder, a magnetic alloy material composed of Al, Si, Fe, etc.,
Permalloy, sendust, metal such as Fe, high magnetic permeability material,
Mn-Zn ferrite, Co-Zn ferrite, Ni-
Ferrites such as Zn ferrite and metal amorphous materials can be mentioned.

As the resin binder (or ink vehicle) in which the above hard magnetic powder or soft magnetic powder is dispersed, butyral resin, vinyl chloride / vinyl acetate copolymer resin, urethane resin, polyester resin, cellulose resin, acrylic resin A styrene / maleic acid copolymer resin or the like is used, and a rubber resin such as a nitrile rubber or a urethane elastomer is added as necessary. Further, in consideration of heat resistance, a resin having a high glass transition temperature (Tg) such as polyamide, polyimide, or polyethersulfone, or a system in which Tg increases by a curing reaction can be used. As necessary, a pigment such as a surfactant, a silane coupling agent, a plasticizer, a wax, a silicone oil, or carbon is added to the dispersion of the magnetic particles dispersed in the resin or the ink vehicle as described above. You may.

The hard magnetic layer 5 and the soft magnetic layer 7 constituting the magnetic layer 4 are formed by the above-described hard magnetic material or soft magnetic material itself by a vacuum deposition method, a sputtering method, a plating method, or the like. Can also.

Here, the soft magnetic layer has a magnetization direction reversed by a magnetic field generated in a read magnetic head to which a reproducing bias current is applied.
The magnetization direction is not reversed by the generated magnetic field. Generally, in order to reverse the magnetization direction of the magnetic layer, it is necessary to apply an external magnetic field that is about three times the coercive force (coercive force) of the magnetic layer. Therefore, in the present invention, the coercive force of the soft magnetic layer is smaller than the coercive force of the hard magnetic layer. For example, for a magnetic head that generates a magnetic field having a strength of 30 [Oe] as a bias magnetic field, a magnetic layer having a coercive force of 10 [Oe] or less as a soft magnetic layer and a coercive force of 100 [Oe] or more as a hard magnetic layer. Are preferred.

The substrate 2 constituting the information recording medium 1 is made of nylon, cellulose diacetate, cellulose triacetate, vinyl chloride, polystyrene, polyethylene, polypropylene, polyester in consideration of heat resistance, strength, rigidity and the like required for the substrate. It can be composed of a composite material alone or in combination of materials appropriately selected from materials such as resins such as polyimide, polycarbonate, biodegradable resins, metals such as copper and aluminum, paper, and impregnated paper. The thickness of such a substrate 2 is 0.005 mm to
It can be about 5 mm.

The information recording medium 1 described above includes a concealing layer for making it difficult to recognize the pattern of the irregularities 7a constituting the fixed magnetic information and a protective layer (including a pattern) for improving the protection and decoration effect. It may be provided on the soft magnetic layer 7. Such a concealing layer and a protective layer are made of cellulose derivatives such as ethyl cellulose, cellulose nitrate, ethyl hydroxyethyl cellulose, cellulose acetate propionate, and cellulose acetate; polystyrene, poly-α-
Styrene resin such as methylstyrene or styrene copolymer resin; Acrylic resin or methacrylic resin such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate or copolymer resin; rosin, rosin modified Rosin ester resins such as maleic acid resin, rosin-modified phenol resin, and polymerized rosin; colors to be colored on binders such as polyvinyl acetate resin, coumarone resin, vinyl toluene resin, vinyl chloride resin, polyester resin, polyurethane resin, and butyral resin Various pigments are added according to, and if necessary, titanium oxide, alumina powder, micro silica, etc. which have a magnetic head cleaning effect are added, and further, if necessary, a plasticizer, a stabilizer, a wax, Grease,
After adding a drying agent, a drying aid, a curing agent, a thickening agent, and a dispersing agent, knead well with a solvent or diluent, and then use a coloring paint or ink. It can be formed by a coating method such as a method or an offset method or a printing method.

Next, the magnetic recording method of the present invention will be described with the information recording medium 1 as an example.

As shown in FIG. 4, in the magnetic recording method of the present invention, as shown in FIG. 4, the read magnetic field is applied in the direction of the arrow while applying a predetermined reproducing bias current on the information recording section 3 of the information recording medium 1. The head H1 is scanned to read the fixed magnetic information composed of the irregularities 7a, and at the same time, the write-only information is written to the area other than the information recording section 3 of the information recording medium 1 where the hard magnetic layer 5 is formed. The magnetic head H2 is scanned in the direction of the arrow, and the same magnetic information as the fixed magnetic information read by the magnetic head H1 is recorded on the hard magnetic layer 5 to form the provisional track T. In this case, the magnetic head H1 and the magnetic head H2 are scanned integrally, and a provisional track T is formed in parallel with the information recording unit 3.

Next, as a second step, as shown in FIG. 5, the magnetic head H4 for reading is scanned on the temporary track T in the direction of the arrow to read the magnetic information recorded on the temporary track. At the same time, the magnetic head H3 for writing is scanned over the information recording section 3 in the direction of the arrow, and the magnetic information read by the magnetic head H4 is recorded on the hard magnetic layer 5 as it is. In this case, the magnetic head H3 and the magnetic head H4 are scanned integrally.

By the above operation, as shown in FIG. 6, the information recording medium 1 in which the same variable magnetic information as the fixed magnetic information by the unevenness 7a is recorded on the hard magnetic layer 5 is obtained.
The variable magnetic information recorded on the hard magnetic layer 5 is completely synchronized with the fixed magnetic information by the unevenness 7a. This is because, as described above, the magnetic heads H1 and H2 are integrally scanned in the first stage and the magnetic heads H3 and H4 are integrally scanned in the second stage, so that the relative speed between the information recording medium 1 and the magnetic head may change. This is because there is no deviation between the fixed magnetic information and the variable magnetic information.

Thereafter, as shown in FIG. 7, the magnetic information recorded on the provisional track T is erased by the erasing magnetic head H5.

In the magnetic recording method of the present invention described above, the magnetic head H1 and the magnetic head H2 in the first stage and the second
The positional relationship between the magnetic head H3 and the magnetic head H4 at the stage is assumed to be the same in the scanning direction without any deviation, or if there is a deviation, the deviation between the magnetic head H1 and the magnetic head H2, It is necessary to make the displacement between the head H3 and the magnetic head H4 the same.

The time delay between reading by the magnetic head H1 and writing by the magnetic head H2 in the first stage and the time delay between reading by the magnetic head H4 and writing by the magnetic head H3 in the second stage are considered. If necessary, the adjustment is performed so that the fixed magnetic information by the unevenness 7a and the variable magnetic information recorded on the hard magnetic layer 5 are synchronized. In this case, for example, if the scanning speed is set sufficiently slower than the delay time, the effect of the time delay can be ignored. Alternatively, when the scanning speed is stable with high accuracy, the magnetic head H
1 and the magnetic head H2 and between the magnetic head H4 and the magnetic head H3, the write magnetic heads H2 and H3.
By adjusting appropriately so that is the upstream side,
The influence of the time delay can be eliminated.

Further, when an azimuth exists between the head gap of the magnetic head and the scanning direction, the azimuths of the reading magnetic head H1 and the writing magnetic head H3 are made the same, and the writing magnetic head H2 is formed. And reading magnetic head H
The azimuths of 4 must be the same.

In the above magnetic recording method, when a read / write magnetic head is used as the magnetic head H1, the magnetic head H1 is used instead of the magnetic head H3, and the read / write is used as the magnetic head H2. A magnetic head for dual use is used, and a magnetic head H2 is used instead of the magnetic head H4.

Further, it goes without saying that scanning may be performed by transporting the information recording medium 1 while fixing each magnetic head.

Here, reading of magnetic information from an information recording medium on which variable magnetic information identical to fixed magnetic information is recorded in synchronization with the magnetic recording method of the present invention will be described.

When a magnetic head for reading is scanned in the direction of the arrow while applying a predetermined reproducing bias current on the information recording section 3 of the information recording medium 1 shown in FIG. 6, (A) in FIG.
Are detected as shown in FIG. This magnetic signal is superimposed information in which the magnetic output from the fixed magnetic information due to the unevenness 7a and the magnetic output from the variable magnetic information recorded in synchronization with the hard magnetic layer 5 are combined. Are detected as the sum of the magnetic outputs. This is because the same variable magnetic information as the fixed magnetic information is synchronously recorded on the hard magnetic layer 5 as described above.

Next, when the erasing is performed by scanning the information recording section 3 of the information recording medium 1 shown in FIG. 6 with the erasing magnetic head, the variable magnetic information recorded on the hard magnetic layer 5 is obtained. Will be erased. Thereafter, similarly to the above, when the reading magnetic head is scanned in the direction of the arrow while applying a predetermined reproducing bias current on the information recording section 3, a magnetic signal as shown in FIG. 8B is detected. Is done. The output B of the magnetic signal is only the magnetic output from the fixed magnetic information by the unevenness 7a. Therefore, the output B after erasure of the variable magnetic information recorded on the hard magnetic layer 5 is smaller than the output A after erasure.

Therefore, by comparing the contents of the magnetic information read before and after such an erasing operation with the output and confirming that the same magnetic information having a low output can be obtained after the erasing operation, information recording can be performed. It is possible to accurately determine the authenticity of the medium. In this case, a part of the variable magnetic information recorded on the hard magnetic layer 5 may be erased.

The information recording medium 1 is, as described above,
After erasing part or all of the variable magnetic information recorded on the hard magnetic layer 5, it is extremely difficult to return the output B of the erased area to the output A before erasure by another method instead of the magnetic recording method of the present invention. Have difficulty. This is because even if the same variable magnetic information as the fixed magnetic information is to be synchronously recorded on the hard magnetic layer 5, the fixed magnetic information and the variable magnetic information are not changed due to a slight change in the transport state of the information recording medium 1 during recording. This is because interference occurs between the above and the magnetic output level of the superimposed information, and the content of the information changes. Therefore, it is impossible to illegally reuse the information recording medium of the present invention after use is completed.

Next, a first embodiment of the magnetic recording apparatus will be described.

FIG. 9 is a schematic diagram showing one embodiment of the magnetic recording apparatus of the present invention. As shown in FIG. 9, a magnetic recording apparatus 11 of the present invention includes a transport unit 12 for transporting an information recording medium, a first magnetic head unit 13 and a second magnetic head disposed on the transport unit. Part 15, degaussing part 17,
And a control device 18.

Transport means 12 constituting magnetic recording apparatus 11
Is to transport the information recording medium at a constant speed,
Specifically, the information recording medium passes between the upper and lower pairs of rollers, a mechanism that drives one roller by a motor, etc., and the driving force of the motor is transmitted to the upper and lower pairs of belts, It comprises a known mechanism such as a mechanism in which the information recording medium is conveyed in a state of contacting the belt with the surface. The transport speed of the information recording medium by the transport unit 12 can be set, for example, in a range of 6 to 120 m / min. In the illustrated example, the information recording medium is conveyed by the conveying means 12 in the direction of the arrow.

The first magnetic head section 13 includes a support member 13a
A magnetic head H1 for reading and a magnetic head H2 for writing are mounted in parallel at a predetermined interval. The support substrate 13a is provided at a predetermined distance from the transporting means 12, and is set so that the magnetic heads H1 and H2 can contact and scan the surface of the information recording medium transported by the transporting means 12. I have. In this case, in the example of the information recording medium 1 described above, the reading magnetic head H1 scans over the information recording unit 3, and the writing magnetic head H2 has the hard magnetic layer 5 other than the information recording unit 3. Area (provisional track T
The upper part is scanned. It should be noted that known magnetic heads can be used as the magnetic head H1 for reading and the magnetic head H2 for writing. Also, a magnetic head H for reading
Regarding 1, bias reading in which two coils are wound, a constant current is applied to one coil, and an induced current or voltage induced when the magnetic head scans over the information recording unit is detected by the other coil. It is also possible to use a magnetic head capable of performing the above.

The second magnetic head section 15 is configured such that a magnetic head H3 for writing and a magnetic head H4 for reading are mounted in parallel on a support member 15a at a predetermined interval. The support member 15a is disposed at a predetermined distance from the transport unit 12 with respect to the first magnetic head unit 13 on the downstream side in the transport direction of the information recording medium. The magnetic head H3 and the magnetic head H4 are set so that they can be scanned in contact with the surface. In this case, in the example of the information recording medium 1 described above, the magnetic head H3 for writing scans over the information recording unit 3, and the magnetic head H4 for reading scans with the magnetic head H2 of the first magnetic head unit 13. The scanning is performed on the same area (on the provisional track T) on the information recording medium as is performed. Note that known magnetic heads can be used for the write magnetic head H3 and the read magnetic head H4.

Further, the demagnetizing section 17 has a magnetic head H5 for erasing mounted on a support member 17a. The support member 17a is provided at a predetermined distance from the transport unit 12 on the downstream side in the transport direction of the information recording medium with respect to the second magnetic head unit 15, and is provided for the information recording medium transported by the transport unit 12. The magnetic head H5 is set so that it can scan while contacting the surface. In this case, in the example of the information recording medium 1, the erasing magnetic head H5 is the first magnetic head H5.
The magnetic head H2 of the magnetic head unit 13 and the magnetic head H4 of the second magnetic head unit 15 scan the same area (on the provisional track T) on the information recording medium as scans. A known magnetic head can be used as the magnetic head H5 for erasing.

The control device 18 has an amplifier circuit.
The magnetic heads H1, H for reading are connected to the respective magnetic heads.
4 is converted into a write current in real time and sent to the write magnetic heads H2 and H3. Further, the erase magnetic head H5 is demagnetized to perform DC erasing or AC erasing. It is configured to send current.

In the magnetic recording apparatus 11 of the present invention, the gap g ₁ of the magnetic head H ₁ and the gap g _{2 of} the magnetic head H 2 of the first magnetic head unit 13, and the second magnetic head unit 1
Positional relationship between the gap g ₄ of the gap g ₃ and the magnetic head H4 of the magnetic head H3 of the 5, either assumed that there is no displacement in the same to the scanning direction, if the deviation exists,
Gap g ₁ and the magnetic head H2 gap g ₂ of displacement of the magnetic heads H1, it is necessary to equalize the displacement of the gap g ₄ of the gap g ₃ and the magnetic head H4 of the magnetic head H3.

In view of the relationship between the recording density and the transport speed of the information recording medium (scanning speed of the magnetic head), the time delay between the reading by the magnetic head H1 in the first magnetic head unit 13 and the writing by the magnetic head H2, When it is necessary to consider the time delay between the reading by the magnetic head H4 in the second magnetic head unit 15 and the writing by the magnetic head H3, the fixed magnetic information is finally recorded on the hard magnetic layer 5 by the unevenness 7a. It is necessary to adjust so as to synchronize with the variable magnetic information. In this case, for example, if the scanning speed is set sufficiently slower than the delay time, the effect of the time delay can be ignored. Alternatively, when the scanning speed is stable with high accuracy, the magnetic heads H1, H2, and H4 are used in consideration of the delay time.
And the magnetic head H3 for writing.
2. By properly adjusting H3 to be on the upstream side, the influence of the time delay can be eliminated.

[0066] Further, when there is azimuth between the gap and the scanning direction of the magnetic head, and the azimuth of the gap g ₃ of the gap g ₁ and the magnetic head H3 of the for the write of the magnetic head H1 for reading the same, Magnetic head H2 for writing
Gap g of the magnetic head H4 of the reading gap g ₂
Set the azimuth of ₄ to be the same.

The track width of each magnetic head is, for example, magnetic head H1 = magnetic head H4 ≦ magnetic head H2
= Magnetic head H3 ≤ magnetic head H5.

In the magnetic recording apparatus 11 of the present invention described above, the information recording medium 1 is transported by the transport means 12 and passed through the first magnetic head section 13, the second magnetic head section 15, and the demagnetizing section 17, whereby 4, 5 and 7, the same variable magnetic information as the fixed magnetic information by the unevenness 7a is recorded on the hard magnetic layer 5 in synchronization.

Next, a second embodiment of the magnetic recording apparatus will be described.

FIG. 10 is a schematic diagram showing one embodiment of the magnetic recording apparatus of the present invention. As shown in FIG.
The magnetic recording device 21 of the present invention includes a transport unit 22 for transporting an information recording medium, a magnetic head unit 23, a demagnetizing unit 25, and a control unit 26 disposed on the transport unit. .

Transporting means 22 constituting magnetic recording device 21
Transports the information recording medium in the direction of the arrow at a constant speed, and is the same as the transport means 12 of the magnetic recording apparatus 11 described above, and the description thereof is omitted.

The magnetic head section 23 is configured such that a magnetic head Ha for both writing and reading and a magnetic head Hb for both writing and reading are mounted in parallel on a supporting member 23a at a predetermined interval. The support member 23a is provided at a predetermined distance from the transporting means 22, and the magnetic head Ha and the magnetic head Hb are provided on the surface of the information recording medium transported by the transporting means 22.
Are set so that they can be scanned in contact with each other. in this case,
In the example of the information recording medium 1 described above, the magnetic head Ha scans over the information recording section 3, and the magnetic head Hb scans the area (on the provisional track T) where the hard magnetic layer 5 other than the information recording section 3 exists. It has become. Note that known magnetic heads can be used as the magnetic heads Ha and Hb for both writing and reading. In addition, as a magnetic head Ha for both writing and reading, two coils are wound, a constant current is applied to one of the coils, and an induced current or voltage induced when the magnetic head scans over the information recording unit is used as the other. It is also possible to use a magnetic head having a reading unit capable of performing bias reading as detected by the coil.

The degaussing section 25 is obtained by mounting a magnetic head Hc for erasing on a support member 25a. The support member 25 a is provided at a predetermined distance from the transport unit 22 on the downstream side in the transport direction of the information recording medium with respect to the magnetic head unit 23, and is provided on the surface of the information recording medium transported by the transport unit 22. The magnetic head Hc is set so as to be able to contact and scan at a predetermined pressure. In this case, in the example of the information recording medium 1, the erasing magnetic head Hc scans the same area (on the provisional track T) on the information recording medium as the magnetic head Hb of the magnetic head unit 23 scans. It is supposed to. Note that a known magnetic head can be used as the erasing magnetic head Hc.

The control device 26 has an amplifier circuit, is connected to each magnetic head, converts the magnetic reproduction current received from the magnetic heads Ha and Hb into a write current in real time and sends it to the magnetic heads Ha and Hb. The demagnetizing current is sent to the erasing magnetic head Hc to perform DC erasing or AC erasing.

[0075] In the magnetic recording apparatus 21 of the present invention, the write-read for gap g _r read-write magnetic heads Ha and writing and
Write gap g _w of the magnetic head Hb read-write, and the position of the reading gap g _r of the write gap g _w and the magnetic head Hb write-read-write magnetic head Ha of the write-read-write relationship, or assumed that there is no displacement in the same to the scanning direction, if the deviation exists, the write gap g _w of the gap g _r and the magnetic head Hb the reading of the magnetic heads Ha deviation, the deviation of the reading gap g _r of the write gap g _w and magnetic head Hb of magnetic heads Ha should be the same.

Further, from the relationship between the recording density and the transport speed of the information recording medium (scanning speed of the magnetic head), the reading by the magnetic head Ha in the magnetic head section 23 and the magnetic head H
b and the magnetic head H
If it is necessary to consider the time delay between the reading by the magnetic head Ha and the writing by the magnetic head Ha, finally the unevenness 7a
It is necessary to adjust the fixed magnetic information and the variable magnetic information recorded on the hard magnetic layer 5 to be synchronized. In this case, for example, if the scanning speed is set sufficiently slower than the delay time, the effect of the time delay can be ignored.

[0077] Further, when there is azimuth between the gap of the magnetic head and the scanning direction, the write gap for reading the read-write magnetic head Ha g _r and the write gap g
The azimuth of _w is the same, set the azimuth of the reading gap g _r and the write gap g _w of the magnetic head Hb write-read-write to the same.

The track width of each magnetic head is preferably set so as to increase, for example, in the following order: read track width ≦ write track width ≦ erase track width.

Here, the above-described magnetic recording apparatus 21 of the present invention
An example of the operation of (1) will be described by taking recording on the information recording medium 1 as an example. First, the information recording medium 1 is transported in the direction of the arrow by the transport means 22 and is passed through the magnetic head unit 23. At this time, the fixed magnetic information composed of the irregularities 7a of the information recording section 3 is read by the magnetic head Ha for both writing and reading, and at the same time, the magnetic head Hb for both writing and reading other than the information recording section 3 of the information recording medium 1. In the region where the hard magnetic layer 5 is formed, the same magnetic information as the fixed magnetic information read by the magnetic head Ha is recorded on the hard magnetic layer 5 to form the provisional track T. This operation corresponds to the first stage of the magnetic recording method of the present invention shown in FIG.

Next, the transporting means 22 is operated in the reverse direction to return the information recording medium 1 to the upstream side of the magnetic head section 23 (to the right of the magnetic head section 23 in FIG. 10). The information recording medium 1 is transported by operating in the direction (arrow) to pass through the magnetic head 23. At this time,
The magnetic information recorded on the provisional track is read by the write / read magnetic head Hb, and at the same time, the information read by the magnetic head Hb is recorded on the hard magnetic layer 5 by the write / read magnetic head Ha. You. This operation corresponds to the second stage of the magnetic recording method of the present invention shown in FIG.

Next, the information recording medium 1 is conveyed in the direction of the arrow by the conveying means 22 and is passed through the degaussing section 25. At this time, the magnetic information recorded on the provisional track T is erased by the erasing magnetic head Hc. This operation corresponds to the third step of the magnetic recording method of the present invention shown in FIG.

The information recording medium to be recorded by the magnetic recording method and the magnetic recording apparatus of the present invention is the same as that shown in FIG.
The present invention is not limited to the information recording medium shown in FIG. For example, a magnetic layer is formed by laminating a hard magnetic layer and a soft magnetic layer in this order on a substrate, and an information recording medium in which minute irregularities are formed on a boundary surface between the hard magnetic layer and the soft magnetic layer. A magnetic layer is formed by laminating a magnetic layer and a hard magnetic layer in this order, and an information recording medium in which fine irregularities are formed on the soft magnetic layer at the interface with the substrate, a soft magnetic layer and a hard magnetic layer on the substrate. A magnetic layer is formed by sequentially laminating the magnetic recording layer, an information recording medium in which minute irregularities are formed on a boundary surface between the soft magnetic layer and the hard magnetic layer, and a hard magnetic layer is formed on a substrate to form a magnetic layer. An information recording medium in which fine irregularities are formed on the surface of the magnetic layer, a hard magnetic layer is formed on the substrate to form a magnetic layer, and fine irregularities are formed on the interface side of the magnetic layer with the substrate. An information recording medium or the like is also a recording target by the magnetic recording method and the magnetic recording device of the present invention.

Further, the information recording medium to be recorded by the magnetic recording method and the magnetic recording apparatus of the present invention may have any shape such as a card shape, a sheet shape and a roll shape.

[0084]

Next, the present invention will be described in more detail with reference to specific examples.

First, a magnetic coating material A for a hard magnetic layer and a magnetic coating material B for a soft magnetic layer having the following compositions were prepared.

Composition of magnetic coating material A : Ba ferrite powder: 41 parts by weight Polyurethane resin: 7 parts by weight Methyl ethyl ketone: 25 parts by weight Toluene: 25 parts by weight Isocyanate curing agent: 2 parts by weight Composition of magnetic coating material B -Permalloy powder ... 41 parts by weight-Polyurethane resin ... 7 parts by weight-Methyl ethyl ketone ... 25 parts by weight-Toluene ... 25 parts by weight-Isocyanate-based curing agent ... 2 parts by weight Next, a 250 m thick polyethylene terephthalate card substrate is used as a substrate. Is prepared, a magnetic coating A is applied by gravure coating on the card substrate to form a hard magnetic layer having a thickness of 10 μm, and then the magnetic coating B is applied by gravure coating on the hard magnetic layer. Thus, a soft magnetic layer having a thickness of 10 μm was formed. In the formation of this magnetic layer, magnetic orientation treatment was performed with a facing magnet or facing solenoid, and then drying and solidification were performed.

Next, in a predetermined region of the soft magnetic layer, the wavelength λ =
A plurality of minute concave portions were formed using Nd: YAG laser light having an output of 1.06 μm and an output of 15 W. The recesses are arranged along the scanning direction of the magnetic head, and the depth of the recesses is about 4 μm.
The width of the concave portion (the width of the convex portion generated between the concave portions) was fixed at 80 μm. Thus, an information recording medium having a layer configuration as shown in FIG. 2 was produced.

Further, a coating for a concealing layer having the following composition was applied by gravure coating on the soft magnetic layer having the irregularities formed thereon to form a concealing layer having a thickness of 3 μm, thereby obtaining an information recording medium.

Composition of paint for concealing layer : Alumina powder: 20 parts by weight Polyurethane resin: 18 parts by weight Cyclohexanone: 31 parts by weight Toluene: 31 parts by weight On the other hand, the magnetic material of the present invention having the structure shown in FIG. A recording device was manufactured. In this magnetic recording apparatus, the conveying means conveys the information recording medium by belt driving, and the track width of each magnetic head of the first magnetic head unit, the second magnetic head unit, and the demagnetizing unit is set as follows. The center lines of the track widths of H1 and H3 are matched, and the magnetic head H2
And the center line of the track width of H4.
Further, the magnetic heads H1 and H2 of the first magnetic head unit and the magnetic heads H3 and H4 of the second magnetic head unit are set so as not to be displaced in the transport direction (scanning direction) of the information recording medium. The magnetic head H1 used for reading was a magnetic head capable of bias reading.

Track width of magnetic head • Magnetic head H1 for reading: 3 mm • Magnetic head H2 for writing: 4 mm • Magnetic head H3 for writing: 4 mm • Magnetic head H4 for reading: 3 mm • Erase for erasing Magnetic head H5: 5 mm Next, in this magnetic recording apparatus, the information recording medium was conveyed at a constant speed of 18 m / min in the direction of the arrow in FIG. 9 to perform magnetic recording. In this case, a read bias current of 100 mA DC is applied to the read magnetic head H1 in the first magnetic head unit to read fixed magnetic information due to minute unevenness of the soft magnetic layer of the information recording unit, and the same magnetic information as the read fixed magnetic information is read. Information was recorded on the hard magnetic layer outside the information recording portion by the magnetic head H2 to form a provisional track.
Next, in the second magnetic head unit, the magnetic information of the provisional track is read by the magnetic head H4,
The same magnetic information as the read magnetic information was recorded on the hard magnetic layer of the information recording section by the magnetic head H3, and then the magnetic information of the provisional track was erased by the erasing magnetic head H5 in the demagnetizing section.

As a result of scanning the reading magnetic head at a constant speed while applying a reproducing bias current of 100 mA DC to the information recording portion of the information recording medium on which the magnetic recording was performed as described above, the magnetic output was 9 V. A reproduced waveform of (pp) was obtained. Thereafter, the erasing magnetic head is scanned over the information recording section to apply a DC magnetic field to perform degaussing, and then read in the same manner as described above. As a result, a magnetic output of 4 V (p− The reproduced waveform of p) was obtained.

[0092]

As described in detail above, according to the present invention,
The fixed magnetic information consisting of a plurality of fine irregularities arranged along the scanning direction of the magnetic head of the information recording unit is temporarily recorded on the hard magnetic layer in the area other than the information recording unit by scanning the magnetic heads integrally. Then, the provisional track is formed, and then the magnetic information of the provisional track is recorded on the hard magnetic layer of the information recording section by scanning with the two magnetic heads integrally. In the information recording medium on which the same variable magnetic information is recorded in synchronization with the hard magnetic layer constituting the magnetic layer, and such magnetic recording is performed,
When the magnetic head is scanned over the information recording unit, superimposed information of the magnetic output obtained by combining the magnetic output from the fixed magnetic information and the magnetic output from the variable magnetic information is obtained, and the variable magnetic information recorded on the hard magnetic layer is obtained. When information is erased, only the magnetic output from the fixed magnetic information in the erased area causes a drop in output, and the erased area can be easily recognized. On the other hand, the same variable magnetic information as the fixed magnetic information is recorded on the hard magnetic layer. Even if an attempt is made, slight variations in the transport state of the information recording medium during recording may cause interference between the fixed magnetic information and the variable magnetic information, resulting in a difference from the output level of the superimposed information or a change in the content of the information. Therefore, forgery prevention can be reliably achieved, and asymmetric reuse after use can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of a card-shaped information recording medium for explaining an example of an information recording medium to be recorded by a magnetic recording method and a magnetic recording device of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a diagram illustrating a format example of a digital signal of 1, 0;

FIG. 4 is a diagram for explaining the magnetic recording method of the present invention.

FIG. 5 is a diagram for explaining the magnetic recording method of the present invention.

FIG. 6 is a diagram of an information recording medium showing a state after the same variable magnetic information and the same variable magnetic information are synchronously recorded on the hard magnetic layer.

FIG. 7 is a diagram for explaining the magnetic recording method of the present invention.

FIG. 8 shows the reproduction waveform output of the information recording medium after the fixed magnetic information and the same variable magnetic information are recorded on the hard magnetic layer in synchronization with the magnetic recording method of the present invention, and the reproduction waveform output after demagnetizing the same track. FIG.

FIG. 9 is a schematic configuration diagram for explaining an embodiment of a magnetic recording device of the present invention.

FIG. 10 is a schematic configuration diagram for explaining an embodiment of a magnetic recording device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Information recording medium 2 ... Substrate 3 ... Information recording part 4 ... Magnetic layer 5 ... Hard magnetic layer 7 ... Soft magnetic layer 7a ... Concavo-convex 11, 21 ... Magnetic recording device 12, 22 ... Conveying means 13 ... 1st magnetic head part 15: second magnetic head section 17: degaussing section 23: magnetic head section 25: degaussing section

Claims (9)

[Claims] An information recording unit includes: a substrate; and an information recording unit formed on the substrate, the information recording unit including at least a magnetic layer having a hard magnetic layer, and the magnetic layer includes a magnetic layer in a scanning direction of a magnetic head. In an information recording medium on which fixed magnetic information composed of a plurality of fine irregularities arranged along a line is recorded, magnetic information for synchronously recording the same variable magnetic information as the fixed magnetic information on the hard magnetic layer is recorded. A recording method, wherein a magnetic head is scanned over the information recording section to read the fixed magnetic information comprising the irregularities, and at the same time, an area other than the information recording section and in which a hard magnetic layer is formed. A second magnetic head is scanned integrally with the magnetic head, and the same magnetic information as the fixed magnetic information read by the magnetic head is recorded on the hard magnetic layer to form a provisional track.
And scanning the magnetic head on the provisional track to read magnetic information recorded on the provisional track, and at the same time, simultaneously scanning another magnetic head on the information recording unit with the magnetic head. A second step of recording magnetic information read by the magnetic head on the hard magnetic layer. 2. The magnetic recording method according to claim 1, further comprising a third step of erasing magnetic information recorded on the temporary track. 3. The information recording medium, wherein the magnetic layer has a soft magnetic layer, and the unevenness is formed on the soft magnetic layer, and a predetermined bias current is applied on the information recording section in the first step. 3. The magnetic recording method according to claim 1, wherein the magnetic head is caused to scan. 4. A transport unit for transporting an information recording medium, a first magnetic head unit and a second magnetic head unit sequentially disposed along a transport direction of the information recording medium by the transport unit, The first magnetic head unit scans a magnetic head H1 for reading provided at a position for scanning the information recording unit of the information recording medium conveyed by the conveying unit, and a portion separated by a predetermined distance from the information recording unit. A write magnetic head provided at a position for scanning an information recording portion of an information recording medium conveyed by the conveyance means. A magnetic recording apparatus, comprising: a magnetic head H3; and a reading magnetic head H4 provided at a position for scanning the same portion on the information recording medium scanned by the magnetic head H2. 5. A demagnetizing section is provided downstream of the second magnetic head section in the transport direction of the information recording medium, and the demagnetizing section is provided on the information recording medium scanned by the magnetic head H2 and the magnetic head H4. 5. The magnetic recording apparatus according to claim 4, further comprising an erasing magnetic head H5 provided at a position for scanning the same portion. 6. The magnetic recording apparatus according to claim 4, wherein the magnetic head H1 is a magnetic head capable of bias reading. 7. A transport unit for transporting an information recording medium, and a magnetic head unit disposed on a transport path of the information recording medium by the transport unit, wherein the magnetic head unit is transported by the transport unit. A write / read magnetic head Ha provided at a position for scanning an information recording section of an information recording medium, and a write / read magnetic head provided at a position for scanning a portion at a predetermined distance from the information recording section. A magnetic recording device comprising: a magnetic head Hb. 8. A degaussing section provided downstream of the magnetic head section in the transport direction of the information recording medium, wherein the degaussing section scans the same portion on the information recording medium scanned by the magnetic head Hb. The magnetic recording apparatus according to claim 7, further comprising an erasing magnetic head (Hc) provided in (1). 9. The magnetic recording apparatus according to claim 7, wherein the magnetic head Ha is a magnetic head capable of bias reading.