JPH01211257A - Method for forming protective film of optical information recording medium - Google Patents

Abstract

PURPOSE:To perform the formation of a protective film and level printing, respectively and to manufacture an optical information recording medium at high speed and inexpensively by forming the protection film which protects a reflection film at a unit of first color in a printing process to form a level printing layer, and performing the level printing by the unit of second color and after. CONSTITUTION:In case of performing silk screen printing using ultraviolet ray hardening type ink, a printer is constituted of the printer of one color, the one of two colors, and the one of four colors, etc., and protective coating is performed at the unit of first color. The protection film is set as set-solid so-called in printing, and is set as a set-solid plate of pattern having the same size or a little larger as that of an optical disk. The central part of the plate is set as a part not requiring the protection film, and the part is made up as a non-streak part, and the plate is loaded on the printer, then, the printing of the protection film is performed. And in case of using the printer of two colors, the protection film is formed at the unit of first color, and the printing of a label of single color is performed at the unit of second color. Similarly, in case of using the printer of four colors, the protection film is formed at the unit of first color, the labels up to three colors are printed at the printer of second color and after.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to optical discs typified by compact discs,
The present invention also relates to optical information recording media such as optical cards, and particularly to a method for forming a protective film.

<Prior art and its problems> Light-transmitting materials such as boneate and glass are used, and their applications include compact discs (CDs), laser discs (LDs), recordable and readable discs (CD-ROMs), and writeable discs ( DRAW) and write/erase discs (E
-DRAW) and so on.

Depending on the reproduction method, two sheets of these are pasted together, but in any case, the thickness of the reflective film that reflects the reading light (laser light) is on the submicron order, so it is necessary to protect the reflective surface. , -a is coated with an ultraviolet curing resin by a spin code method and cured to obtain a protective film.

Generally, the coating method on flat substrates is as follows:
Roll coating, spray coating, flow coating, dip coating, etc. are used depending on the purpose, but spin code is popular for coating optical discs. However, the spin code method is subject to time constraints because it involves starting up rotation, stopping one rotation for stable rotation, and repeating stopping. Although it depends on the size of the optical disk, it can be said that the maximum cycle time in the spin coating method is 5 seconds. In addition, the spin cord method has the disadvantage that if foreign matter is present in the resin, the flow of the resin on the coated surface becomes irregular, making it impossible to obtain a uniform coated surface.

Means for Solving Problems> The present invention has been made in view of the above-mentioned current situation, and in the printing process for forming a label printing layer,
By forming a protective film to protect the reflective film in the first color unit and performing label printing in the second and subsequent color units, a protective film and a label printing layer are formed. The present invention provides a method for manufacturing an optical information recording medium that can be manufactured at high speed and with high quality.

<Example> Here, a case of silk screen printing using ultraviolet curable ink will be explained as an example. Printing machines include one-color machines, two-color machines, four-color machines, etc. depending on their use, but in the present invention, a protective film coating is performed in the first color unit. That is, the protective film is interpreted as a so-called solid plate in printing, and a solid plate having a pattern of the same size or slightly larger than that of the optical disc is made. At this time, if the central portion does not require a protective film, the plate may be made so that the corresponding portion becomes a non-printing portion. Generally, the plate is made in the shape of a donut.

By attaching this plate to a printing press and storing ultraviolet-curable ink in the ink reservoir instead of printing ink, a protective film can be formed using the same method as with normal pattern printing.

Since it is a Gino screen printing machine compatible with ultraviolet curable ink, ultraviolet rays can be applied immediately after printing, so if the optical disk is transferred under ultraviolet irradiation, the resin layer will be cured and a uniform coating surface will be obtained. In the case of screen printing, the mesh of the screen is 23, depending on the viscosity of the resin.
Approximately 0 to 305 meshes/inch is appropriate.

In the case of a two-color machine, the first color unit forms a protective film, and the second color unit forms a protective film.
Single-color labels can be printed using colored units. Similarly, in the case of a four-color machine, if a protective film is formed in the first color unit and a label is printed in the second and subsequent color units, it is possible to print from a single color to three colors.

As mentioned above, the present invention forms a protective film in the first color unit of a multicolor printing machine, and performs label printing in the second and subsequent color units, which essentially shortens the time for manufacturing optical discs. At the same time, since the number of steps is reduced, equipment costs are reduced, and there is also the effect of reducing manufacturing costs.

Although the silk screen printing method has been described here for the sake of explanation, the method is not limited to this.

- Which clothes are printed on C (offset, gravure, letterpress)?
Even when printing, a certain amount of pressure (printing pressure) is required to transfer the ink to the printing surface.

In the case of the present invention, since the surface to be printed (surface to be coated) is an extremely thin metal coating (film thickness formed by vacuum evaporation, sputtering, etc., on the order of submicrons) formed on the base material, the printing pressure is Preferably, it is as small as possible. By using a printing method such as a silk screen printing method or a band printing method, a protective film can be formed without damaging the metal coating layer (reflection layer).

Effects> The present invention is as described above, and by using the first color unit of a multicolor printing machine to form a protective film and printing the label from the second color unit onwards, manufacturing time can be shortened. At the same time, by reducing the number of steps, equipment costs can be reduced and an inexpensive optical information recording medium can be obtained.

Special request person Toppan Printing Co., Ltd. Representative: Kazuo Suzuki

Claims (1)

[Claims] (1) In the printing process for forming the label printing layer when producing an optical information recording medium in which a reflective film is formed on the optical information recording layer and a protective film label printing layer is sequentially formed, the first color A protective film for protecting the reflective film is formed in the unit, and a label printing layer is formed in the second and subsequent color units to form a protective layer and a label printing layer. A method for forming a protective film on an information recording medium.