JPS6363144A - Optical card - Google Patents

Abstract

PURPOSE:To prevent writing by reading-out light at the time of turning over and stop of an optical card as the card moves by providing a transparent base material having track grooves on the surface, an optical recording layer on the grooved surface and an opaque card base material in contact with the optical recording layer and providing an unrecordable part to part of the optical recording layer. CONSTITUTION:An optical recording material is provided on the card base material. This optical recording material consists of the transparent base material 21 having the track grooves and the optical recording layer 22 provided on the track groove surface. The optical recording material is so provided that the optical recording layer 22 contacts the opaque card base material 24 and the unrecordable part is provided to part of the optical recording layer 22. The writing by the reading-out light upon stopping of the optical card which arises when the movement of the optical card is turned over during tracking of the card is thereby entirely prevented and the generation of the tracking error is prevented in spite of repeated reading-out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical card, and more particularly to a card-shaped information storage Q carrier for optically recording and reproducing information.

[Prior Art] In recent years, as society has become increasingly information-oriented, information recording carriers and optical media such as optical disks, optical cards, and optical tapes that record or reproduce information optically have become a means of efficiently handling a wide variety of information. Many information recording and reproducing devices have been proposed. Binarized information is stored on the information recording carrier by changes in reflectance, changes in reflected light intensity due to changes in surface shape such as the presence or absence of pits, and changes in the plane of polarization due to magneto-optic effects. There are some methods that can be detected by converting the change into an intensity change. The above-mentioned information recording carrier has excellent features such as a high recording density and a long lifespan because it allows non-contact recording and reproduction.

A card-shaped information recording carrier (hereinafter referred to as an optical card) is highly portable and has a large capacity compared to its size.
Recently, there has been a lot of research and development, and proposals have begun to be made.

Hereinafter, an optical card will be explained as an information recording carrier that optically records and reproduces information.

Regarding optical information recording and reproducing methods, for example, magneto-optical recording is performed in which the direction of magnetization is reversed using an energy beam, recording is performed by forming uneven pits, or recording is performed by increasing or decreasing optical reflectance. Generally, record carriers with high or low optical reflectance are widely used because they have high SN light and are easy to manufacture.

As a record carrier depending on the optical reflectance, for example,
Cards have been proposed that have a recording layer made of silver particles dispersed in a gelatin matrix. Information is written to the recording layer by irradiating the recording layer with a laser beam to form recording bits.

On the other hand again. A so-called heat mode recording material has been proposed in which a recording layer is irradiated with a spot-like energy beam such as a laser beam to change the state of a portion of the recording layer. As these recording layers, metal thin films such as tellurium and bismuth, organic thin films such as polystyrene and nitrocellulose, dye thin films such as cyanines, and tellurium low oxide films utilizing phase transition are used. These recording materials do not require any development processing after information is written, and can be read directly after writing, so-called DR8 (Direct Read After Write).
direct read after write
) media, which allows high-density recording and additional writing.

FIG. 3 is a schematic plan view showing the recording format of a conventional DRAW type optical card.

In FIG. 3, a recording area 2 is provided on an optical card 1 which is a record carrier, and the recording area 2 is formed by a plurality of tracks 3 arranged. Furthermore, a start bit and a stop bit are formed in track 3, and track 3 has an information capacity of about 1000 bits. Further, each track 3 is separated by a reference line 5 (hereinafter referred to as an R line). In addition, arrow A
is the moving direction of the optical card l during playback.

FIG. 4 is a schematic diagram of the optical card reproducing method.

In FIG. 4, an optical card 1 is an IF that can be moved in the direction of arrow A by a rotating mechanism 6. As shown in FIG. Information recorded on the optical card l is read and reproduced by the optical head 11 for each track 3. First, light from a light source 7 such as a semiconductor laser is focused by a lens system 8 and illuminates the track 3 on which information is recorded. The image of the illuminated track 3 is formed on the sensor IO by the imaging optical system 9, and an electrical signal corresponding to the information recorded on the track 3 is output from the sensor IO.

When the reading of the track 3 is completed, the optical card l is moved in the six directions of the arrow, or the optical head 11 is moved in the direction of arrangement of the tracks 3 (direction of the arrow C), and information reading of the next track 3 is performed in the same manner. .

Further, in order to access any track 3 on the optical card 1, the optical head 11 is moved in the direction of arrow C. The optical head 11 selects the track 3 to which the target track 3 to be read belongs by counting the R lines 5,
When it reaches track 3, it stops. Subsequently, the optical card 1 is moved in the six directions of arrows by the one-rotation mechanism 6, and the information on the target track 3 is read.

[Problems to be Solved by the Invention] As described above, the conventional information recording carrier such as the optical card 1 is optically illuminated by the light emitted from the light source 7 disposed in the optical head 11 of the optical recording/reproducing device. Information is recorded or reproduced.

As mentioned above, during tracking during playback of the optical card, the optical card 1 moves in the direction of arrow A by the rotating mechanism 6 and reads information, or as the optical card 1 moves in six directions, the optical It has been found that there are times when the card stops due to the reverse movement, and the writing progresses very gradually due to the energy of the read light, eventually making it difficult to detect the tracking signal.

The present invention has been made for the purpose of solving the above-mentioned problems, and it is an object of the present invention to provide an optical card in which writing by a read light is prevented when the optical card stops being reversed due to movement of the DRAW type optical card. That is.

[Means for solving the problem of Manren point] That is, the present invention provides a transparent base material having track grooves on its surface;
consisting of an optical recording Q layer provided on the track groove surface and an opaque card base material provided in contact with the optical recording layer,
The optical card is further characterized in that a part of the optical recording layer is provided with an unrecordable portion.

The present invention will be explained in detail below.

The optical card according to the present invention is an optical card in which an optical recording material is provided on a card base material, the optical recording material comprising:
It consists of (a) a transparent base material having track grooves, and (b) an optical recording layer provided on the track groove surface, and this optical recording material is provided so that the optical recording layer is in contact with the opaque card base material. The DRAW type optical card is characterized in that a part of the optical recording layer is provided with a non-recordable portion.

Next, the optical card according to the present invention will be explained using a specific example shown in the drawings. FIG. 1 is a sectional view showing one embodiment of an optical card according to the present invention.

In FIG. 1, the optical card according to the present invention includes an optical recording layer 22 provided on the track groove surface of a transparent substrate 21 having a track groove 26, and optical recording layer 22 at both ends (not shown) of the track groove surface. Margin part 2, which is the part that cannot be recorded on the layer
5 and an opaque card base material 24 are provided so as to be in contact with each other via an adhesive layer 23.

If necessary, the optical card may be provided with a magnetic recording layer, an IC memory, an engraved image, a photograph, a character, a mark, an embossed character called an imprint, etc. on the front or back side of the optical card. By doing this, one card can be used in various playback methods, and counterfeiting can be more effectively prevented.

The transparent base material 21 having the track grooves 26 is preferably one that has few inconveniences in optical recording and reproduction.
In addition, thermoplastic materials with good moldability are preferred for forming track grooves. For example, acrylic resins, polyester resins, polycarbonate resins, vinyl resins, polyimide resins, polyacetal resins, polyolefin resins, polyamide resins, cellulose derivatives, etc. can be used.

As the opaque card base material 24, any material that can be used as a normal card base material can be used. Specifically, polyvinyl chloride, vinyl chloride/vinyl vinegar copolymer, polyvinylidene chloride, and Acrylic polymers such as methyl methacrylate, polystyrene, polyvinyl butyral, acetyl cellulose, styrene/butadiene copolymers, polyethylene, polypropylene, polycarbonate, etc. are used. Depending on the case, iron, stainless steel,
Metal sheets of aluminum, tin, copper, zinc, etc., synthetic paper, paper, etc. may also be used6.Furthermore, laminates of the above materials may also be used. These opaque card base materials 24 may be pretreated to improve adhesion, such as corona discharge treatment, plasma treatment, and primer treatment, if necessary.

For the optical recording layer 22, when the wavelength of the energy beam for reproduction is 650 nm or more, especially 700 to 900 nffi, it is preferable that the difference between the reflectance of the bit, which is the recorded part, and that of the unrecorded part is large. . Further, it is preferable that the energy required to cause a change in reflectance due to irradiation with the energy beam for recording is smaller. Furthermore, it is preferable that the reflectance of the recorded and unrecorded areas does not change due to the reproduction energy beam. For example, T
e, Sb.

Oxides such as No, Ge, V, Sn, Te-3n,
Compounds such as TeOx-Ge undergo a phase transition when irradiated with an energy beam, and their reflectance changes. Also, T
e-C114°Te-C3z, Te-styrene, 5
Composites of metals such as n-5O□, Ge5-8n, 5nS-5 and organic compounds or inorganic sulfides, and SiO□
A multilayer film such as /Ti/Sing/Aj) can also be used. Further, it is also possible to use a thermoplastic resin such as nitrocellulose, polystyrene, or polyethylene in which metal particles such as silver are dispersed, or a thermoplastic resin in which metal particles are aggregated on the surface. In addition, chalcogen or coloring type Mo0=-Cu, l#oo:+
-5n-Cu or the like can also be used, and depending on the case, a multilayer body of a bubble-forming organic thin film and a metal thin film can also be used.

In addition, organic thin films whose optical properties can be changed by energy beams can also be used, such as anthraquinone conductors, especially those with an indathrene skeleton, dioxazine compounds and their derivatives, triphuedithiazine compounds, phenanthrene derivatives, and cyanine compounds. , merocyanine compound,
Examples include pigments such as pyrylium compounds, xanthine compounds, triphenylmethane compounds, croconium colors, base colors, and croconium compounds, which are preferred for the present invention because they can be manufactured continuously by solution coating. It is.

Next, a method for manufacturing an optical card according to the present invention will be explained.

First, track grooves 26 are formed on a transparent substrate 21 made of polymethyl methacrylate resin, polycarbonate resin, etc. by a heat press method, etc. 6 Next, on the track groove surface, first, a layer with almost the same reflectance as the recording layer (reflection ±25 of the rate
%) and does not change at all depending on the energy of the readout light.
It is formed in the margin portion 25 of the figure. After that, an optical recording layer is formed on the track groove portion 28 including the margin portion 25. For example, a solution of cyanine as an organic dye dissolved in a solvent is applied and dried to form the optical recording layer 22. In this case, the margin portion 25 is coated with a solution in which a phthalocyanine having approximately the same reflectance, such as iron phthalocyanine, nickel phthalocyanine, copper phthalocyanine, sodium salt of dicyanocobalt phthalocyanine, cobalt phthalocyanine, etc., is dissolved in a solvent, or a small amount of resin is dissolved in a solvent. Disperse and knead the mixture and apply it in advance. As a coating method, a dip method, a spray method, a spinner method, a bar code method, a blade coat method, a roll coat method, a curtain coat method, etc. can be used.

The film thickness of the margin portion 25 and the optical recording layer 22 is o, t #L
Form into a thin film of about 1. The optical recording material with a part of the optical recording layer made unrecordable is placed in such a way that the optical recording layer 22 is in contact with the opaque card base material 24, and a thermally adhesive adhesive layer 23 is placed in the gap.
An optical card can be manufactured by sandwiching and overlapping the two layers and pressing them with a heat fixing roll heated to about 90 to 150°C.

In some cases, it is possible to further provide a heart coat layer on the transparent base material 21 to prevent scratches on the DRAW type optical card manufactured as described above. Alternatively, in order to increase light resistance, it is also possible to form it on the transparent base material 21 which is an ultraviolet absorbing film. Alternatively, when the transparent base material itself is a resin containing an ultraviolet absorber, this is a preferable configuration because light resistance and durability can be increased simply by providing a hard coat layer.

Next, writing of information to the optical recording layer and reading of information written to the optical card as described above will be explained.

Information is written to the Q layer using a wavelength of 300 to 11,000.
An energy beam of n is focused and irradiated through a lens or the like to form recording pits. The energy intensity at this time is 0.1-100mW, and the pulse width is 5n5ec~5
00m5ec, and the beam diameter is preferably 0.5 to 10p. The energy beam to be irradiated is preferably a laser beam such as a semiconductor laser, an argon laser, a helium-neon laser, or a krypton laser for detecting the track groove.

On the other hand, in order to read information written on the optical card according to the present invention, a low-energy beam that does not alter the recording layer is focused through a lens or the like and irradiated from the transparent base material side of the optical card. , which detects the presence or absence of a bit by correlating the intensity of the reflected light with the phase change.

[Function] In the optical card of the present invention, a margin portion, which is a non-recordable portion, is provided in a part of the optical recording layer provided on the track groove surface of a transparent substrate having track grooves on the surface.
In the margin portion, the reflectance of the margin portion does not change even when the optical card is stopped due to the energy beam irradiation of the reading light, so that no tracking error occurs even if the optical card is repeatedly moved in reverse.

[Examples] Hereinafter, the present invention will be explained with reference to Examples, but the present invention is not limited thereto in any way.

Example 1 Transparent tJ] As a base material, width 54 m+i, length 85.6++
Track grooves were formed on a polymethyl methacrylate film containing an ultraviolet absorber (manufactured by Nitto Jushi Co., Ltd.) having a thickness of 0.3 cm and a thickness of 0.3 cm. Track groove pitch 10m
The track structure width was 34 m, and the track groove depth was 0.2 m.

Next, add a width of 10 mm to both ends of the track groove surface.
(Margin area 25 in FIG. 2), a substance in which copper phthalocyanine is dispersed in PMMA resin is applied with a roll coater, and after drying, it is applied to the track groove area 281 using the following general formula (I
A recording layer having a thickness of about 900 Å was formed by applying a solution of the dye (2) dissolved in 2-butanone using a spinner.

On the other hand, as a card base material, a white hard vinyl chloride film with a thickness of 0.41 is laminated with a thermal adhesive (vinyl chloride-vinyl acetate-maleic acid resin) so that it is in contact with the optical recording layer of the optical recording material. They were then pressed and bonded together using a hot roll with a surface temperature of 120°C. Thereafter, the surface of the transparent substrate was treated with a silicone-based surface hardening agent to produce an optical card.

When using the optical card obtained in this manner, only writing by the read light occurred even when the card stopped reversing, and no tracking error occurred even in 30,000 reciprocating tests.

Example 2 As a transparent base material, track grooves were formed in polycarbonate (Panlite AD-5503, manufactured by Teijin Kasei Corporation) with a thickness of 0.3 cm by a heat press method. The track shape was exactly the same as in Example 1.

In the margin area, add sodium salt of dicyanocobalt phthalocyanine to 5% vinyl acetate in DMF-benzene (1:
1) The solution dissolved in the mixed solution was coated with a roll coater, and after drying, the dye solution used in Example 1 was coated with a spinner to form a recording layer with a thickness of about 1.10 OA.

On the other hand, a thermal adhesive (Daicel Chemical Industries, Plaxel H-7) was added to a white polycarbonate film with a thickness of 0.41 mm as a card base material, and the film was stacked so as to be in contact with the optical recording layer of the optical recording material described above, and the surface temperature They were bonded together by pressure bonding using a hot roll at 120°C.

When using the optical card obtained in this way, writing by the readout light does not occur even when the card stops reversing, and no tracking error occurs even in 30,000 reciprocating tests. .

[Effects of the Invention] The optical card according to the present invention has a transparent substrate having a track groove and an optical recording layer on the track groove surface and a margin portion where the reflectance is almost the same as that of the optical recording layer and where recording is not possible. Writing by the read light due to the stoppage of the optical card that occurs when the movement of the optical card is reversed during tracking of the optical card does not occur at all, and tracking errors do not occur during repeated reading.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of an optical card according to the present invention, FIG. 2 is an explanatory view showing a non-recordable portion provided in an optical recording layer, and FIG. 3 is a schematic cross-sectional view showing an embodiment of an optical card according to the present invention. A schematic plan view showing the recording format of the card and FIG. 4 are schematic diagrams of a conventional optical card reproducing method.

Claims (2)

[Claims] (1) Consisting of a transparent base material having a track groove on its surface, an optical recording layer provided on the surface of the track groove, and an opaque card base material provided in contact with the optical recording layer, and An optical card characterized in that a part of a recording layer is provided with an unrecordable portion. (2) The optical card according to claim 1, wherein the unrecordable portion is provided at the end of the track groove surface on the surface of the transparent base material.