JPS63271738A - Optical type information recording medium - Google Patents

Abstract

PURPOSE:To prevent adhesion of fingerprints to the surface of an optical card by coating a fluorine oil adhesion preventive agent on the surface of a protective layer or adding the same to the protective layer or a surface hardening layer formed on the protective layer. CONSTITUTION:This optical card is formed by providing an Al reflecting layer 22 forming a high reflectivity part on a card base material 21, providing a patterned layer 24 formed with recording bits 23 to form a low reflectivity part on the Al reflecting layer 22, providing the protective layer 25 on the patterned layer 24 and laminating a coating layer 26 of the fluorine oil-adhesion preventive agent as the outermost layer on the protective layer 25. A fluorine surfactant is used as the fluorine oil adhesion preventive agent. The thickness of the coating layer is preferably 5-15mum. The optical card which prohibits adhesion of the fingerprints to the optical information recording layer is thereby obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical information recording medium in which an optical information recording area is formed on a card and a protective layer is provided thereon.

[Prior Art] Conventionally, optical information recording media (which is a form of optical memory)
Optical cards (hereinafter referred to as optical cards) are being researched and developed in various fields as multifunctional cards to replace magnetic cards. This optical card generally uses a light beam such as a laser beam to vaporize or deform a part of the optical recording layer to form a pattern layer, and utilizes changes in optical properties such as transmittance and reflectance. It records and reproduces information.

FIG. 4 is an explanatory diagram showing an example of an optical card recording information reading device. In FIG. 4, l is an optical head unit for reading information, 2 is a light source such as an LED or a semiconductor laser, 3 is an illumination lens, 4 is an optical card as a medium, 5 is an imaging lens, 6 is a mirror, and 7 8 is a reciprocating drive mechanism for the optical cart, 9 is a belt, and 10 is a guide roller.

FIG. 5 is a sectional view showing an example of the optical card 4, in which an information recording layer 13 on which recording bits 12 are formed is provided on a credit-sized plastic substrate 11, and a transparent protective layer 14 is provided on the information recording layer 13. It is coated. Information recorded on the optical card is read out as a difference in reflectance between the recording bit 12 portion and its surrounding portion.

Further, the recording bits 12 on the optical card 4 are arranged in an array, for example, several to several tens of bits as one information unit.
An image is formed on the light receiving surface of the OD.

The CCD of the sensor 7 is, for example, a one-dimensional sensor having a scanning direction parallel to the array, and electrically scans the intensity of the light amount of the projected image of the array of recording bits 12 and converts it into an electric signal.

The optical card 4 is held on a belt 9 by a guide roller 10, and the C of the sensor 7 is moved by a motor (not shown).
It is continuously or intermittently driven back and forth in a main scanning direction substantially perpendicular to the scanning direction of the CD, and different arrays of recorded bits are successively projected onto the light-receiving surface of the CCD. When the reading of information in a certain area in the main scanning direction is completed in this way, the optical head l is moved by a drive mechanism (not shown) to a second reading area a certain distance away in a direction orthogonal to the main scanning direction. It is moved and remains there. Then, the optical cart 4 is driven back and forth again by a motor (not shown),
Information reading from the second reading area is performed.

By scanning the surface of the optical card two-dimensionally through a series of procedures as described above, information is read from a required area on the surface of the optical card.

However, in the above-mentioned information reading method, if a fingerprint is attached to the surface of the transparent protective layer 14 of the optical cart 4, the reflected light from the recording bit 12 is scattered, and the light is accurately placed on the light receiving surface of the CCD of the sensor 7. There is a problem in that the image of the recorded bits is no longer formed, making it impossible to read the information.

On the other hand, since the optical card is handled by hand, it is impossible to avoid touching it with fingers, and it is inevitable that fingerprints will adhere to the surface of the transparent protective layer 14. Therefore, it is necessary to prevent fingerprints from adhering to the surface of the transparent protective layer 14. As a countermeasure, a method has been proposed in which an optical card is housed in a case, and the optical cart is automatically attached and detached from the case by attaching it to an information reading device.

However, this method has the disadvantage that the mechanisms of the optical card and the information reading device become complicated, leading to an increase in cost, and in particular, it significantly impedes portability, which is a characteristic of optical cards.

[Problems to be Solved by the Invention] An object of the present invention is to eliminate the above-mentioned drawbacks of conventional optical cards and to provide an optical card in which fingerprints are less likely to adhere to the optical information recording area. It is something.

[Means for Solving the Problems] That is, in the present invention, an optical information recording area is formed on a substrate, and a protective layer made of resin is provided thereon.

In a card-shaped optical information recording medium in which information is recorded and/or reproduced by two-dimensional movement with respect to a recording and/or reproduction head, a protective layer on the optical information recording medium is coated with a fluorine-based oil. This optical information recording medium is characterized by being subjected to oil adhesion prevention treatment using an anti-adhesion agent.

In the present invention, the oil adhesion prevention treatment includes coating the surface of the protective layer with a fluorinated oil adhesion prevention agent, adding a fluorinated oil adhesion prevention agent to the protective layer, or adding a protective layer on the protective layer. This can be achieved by forming a hardened surface layer made of a different resin, and then adding a fluorine-based oil adhesion inhibitor only to the hardened surface layer.

[Function] The optical cart of the present invention has an optical information recording area formed on a substrate, has a protective layer made of resin on it, and is moved two-dimensionally with respect to the recording and/or reproducing head. In a card-shaped optical information recording medium on which information is recorded and/or reproduced, the protective layer on the optical information recording area is subjected to oil adhesion prevention treatment using a fluorine-based oil adhesion prevention agent. Since the surface tension of the fluorine-based oil adhesion inhibitor is low, the film formed by the fluorine-based oil adhesion inhibitor has an extremely low surface tension.

On the other hand, the reason why fingerprints adhere to the surface of the optical card is that the surface tension of the protective layer surface of the optical cart is greater than the surface tension of oil and water, which are the main components of fingerprints. Due to water migration to the surface of the protective layer.

Either coat the surface of the protective w1 layer of the optical cart with a fluorine-based oil adhesion preventive agent, add a fluorine-based oil adhesion preventive agent to the protective layer, or provide a surface hardening layer to which a fluorine-based oil adhesion preventive agent is added. When oil adhesion prevention treatment is applied, the surface tension decreases.

Therefore, it is possible to reduce the wettability, and it is possible to prevent fingerprints from transferring to the surface of the protective layer.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

FIG. 1 is a sectional view of a read-only optical card showing a first embodiment of the present invention. In FIG. 1, the optical card according to the present invention has a reflective layer 22 that forms a high reflectance section on a card base material 21, and a low reflectance section that is formed on the AR reflective layer 22. A pattern layer 24 in which recording pits 23 are formed is provided, a protective layer 25 is provided on the pattern layer 24, and a coating layer 26 of a fluorine-based oil adhesion prevention agent is laminated as the outermost layer on the protective layer 25. It is what it is.

The card base material 21 is made of a material that serves as a strong support for the optical card, and is made of plastic such as polyvinyl chloride.

The recording pits 23 are formed, for example, on a thin film by silver salt recording using a mask exposure method or by printing technology.

Protective layer 25 haha! The reflective layer 22 and pattern layer 24 are damaged.

Constructed from a plastic such as polycarbonate resin that protects from dirt and environmental conditions.

In the present invention, the fluorine-based oil adhesion prevention agent used is a fluorine-based surfactant, which has been commercialized into various products, such as Surflon, a trade name manufactured by Asahi Glass.

The thickness of the coating layer of the fluorine-based oil adhesion prevention agent does not need to be particularly limited, but is usually 5 to 15 mm thick. m is desirable.

Further, coating can be performed by a usual coating method, such as a dipping method, an air spray method, etc.

FIG. 2 is a sectional view of a read-only optical card showing a second embodiment of the present invention. In the figure, 27 is a protective layer to which a fluorine-based oil adhesion inhibitor 28 is added.

In this example, the method of coating the surface of the protective layer with the fluorine-based oil adhesion inhibitor as shown in FIG. 1 was changed to the method of adding the fluorine-based oil adhesion inhibitor to the plastic forming the protective layer. The coating layer of the fluorine-based oil adhesion prevention agent is a thin film, and there is a problem in that it has poor durability depending on the usage conditions, but this example is an improvement on this problem.

The amount of fluorine-based oil adhesion inhibitor added to the protective layer is usually 1 to 1.
5% by weight is desirable.

According to this example, since the fluorine-based oil adhesion prevention agent is added to the protective layer, the adhesion to the surface of the protective layer is improved, and even if the coating is lost, it can be replenished to some extent from within, increasing durability. will improve.

FIG. 3 is a sectional view of a read-only optical card showing a third embodiment of the present invention. In FIG. This is a hardened surface layer for preventing scratches, made of, for example, Three Bond 3070 or the like, to which a fluorine-based oil adhesion inhibitor is added.

In this example, a hardened surface layer for preventing scratches was further formed on the protective layer, and a fluorine-based oil adhesion inhibitor was added to the hardened surface layer.

The amount of the fluorine-based oil adhesion inhibitor added in the hardened surface layer is usually preferably 0.5 to 5% by weight.

In optical cards, polycarbonate resin is often used for the protective layer because it has high light transmittance. However, adding additives such as fluorine-based oil adhesion inhibitors causes a decrease in transmittance. Furthermore, as mentioned above, the fluorine-based oil adhesion inhibitor added to the protective layer is used only near the surface. Therefore, according to this embodiment, since the fluorine-based oil adhesion prevention agent is added to the thin surface hardening layer formed on the protective layer, the light transmittance may be reduced without interfering with the fingerprint adhesion prevention effect. can be suppressed as much as possible.

In each of the above embodiments, a read-only type optical card is shown, but the present invention is not limited to the read-only type, and can also be applied to write-once type, rewritable type, etc. optical cards. .

[Effects of the Invention] As explained above, in the optical cart of the present invention, a fluorine-based oil adhesion prevention agent is coated on the surface of the protective layer or added to the protective layer or the surface hardening layer formed on the protective layer. By doing so, it is possible to obtain an excellent effect of preventing fingerprints from adhering to the surface of the optical card.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an optical cart showing a first embodiment of the invention, FIG. 2 is a sectional view of an optical card showing a second embodiment of the invention, and FIG. 3 is a sectional view of an optical card showing a third embodiment of the invention. FIG. 4 is an explanatory diagram of an optical card recording information reading device, and FIG. 5 is a sectional diagram of a conventional optical card. 1... Optical head section 2°... Light source 3... Illumination lens 4... Optical cart 5... Imaging lens 6... Mirror 7... Sensor 8
...Reciprocating drive mechanism 9...Belt 10-
...Guide roller 11...Plastic substrate 13
... Information recording layer 14 - ... Transparent protective layer 21 -
...Cart base material 22-Aj) Reflective layer 12.2
3-...recording pit 24...pattern layer 25
．． 27...Protective layer 26...Coating layer 28...Fluorine oil adhesion prevention agent 29-...Surface hardening layer Fig. 1 Fig. 2 Fig. 5

Claims (4)

[Claims] (1) An optical information recording area is formed on a substrate, a protective layer made of resin is provided thereon, and the recording and/or reproducing head is moved two-dimensionally to record and/or reproduce information. A card-shaped optical information recording medium in which an oil adhesion prevention treatment is applied to the protective layer on the optical information recording area using a fluorine-based oil adhesion prevention agent. recoding media. (2) The optical information recording medium according to claim 1, wherein the surface of the protective layer is coated with a fluorine-based oil adhesion inhibitor. (3) The optical information recording medium according to claim 1, wherein a fluorine-based oil adhesion inhibitor is added to the protective layer. (4) The optical information recording medium according to claim 1, wherein a surface hardening layer containing a fluorine-based oil adhesion inhibitor is provided on the protective layer.