JPS62112248A - Production of optical disk - Google Patents

Abstract

PURPOSE:To produce the titled disk with high productivity by forming a functional metallic thin film layer with use of a transfer material on the surface of an optical disk substrate simultaneously with or immediately after the molding of the optical disk substrate. CONSTITUTION:A releasable layer, a colored pattern layer, a metallic thin film layer, and an adhesive layer are successively formed on a substrate sheet to obtain the transfer material. The metallic thin film layer, etc., formed on the transfer material are transferred simultaneously with or immediately after the molding of the optical disk substrate, and the functional metallic thin film layer is formed on the surface of the optical disk substrate. One of the essential components, the metallic thin film layer, consisting of silver, aluminum, nickel, tellurium, etc., is formed on the substrate or the colored pattern layer so that the whole surface or at least the requisite part corresponding to the size of the optical disk substrate surface is covered. One of the essential components, the adhesive layer, is used for retaining the metallic thin film layer on the optical disk substrate.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to read-only optical discs such as compact discs, video discs, laser discs (trademark), etc., and to write and rewrite information. The present invention relates to a method for manufacturing an optical disc that can be manufactured in a large scale, and more specifically, it relates to a method for manufacturing an optical disc that is excellent in production efficiency and good yield rate and is suitable for large-scale production.

<Prior Art> Conventionally, as a method for manufacturing an optical disc, first, if necessary, a concave-convex signal carrier or a tracking signal carrier called a stamper is mounted in an injection mold.
For example, an optical disc substrate is manufactured by injection molding using polycarbonate resin and forming the concavo-convex signals on the polycarbonate molded product, and then a gold G3 film layer of aluminum, nickel, tellurium, etc. is applied to the surface of the optical disc substrate. There is a known method of manufacturing by forming by means such as vacuum evaporation method and sputtering method.

<Problem that the invention seeks to solve> The above-mentioned conventional technology has the following problems.

That is, in the process of forming a metal thin film layer on the surface of the optical disk substrate, it is necessary to place the optical disk substrate manufactured by injection molding in a vacuum and use a punch processing system, which greatly improves production efficiency. It was inferior to

In addition, the gold metal blue layer has 500 to 600 people.
Since it is a functional metal thin film that enables reading, writing, and rewriting of information with υ11-, it must be handled in a very clean environment, but the process of forming this metal thin film layer This process needs to be carried out after the precision-molded optical disk substrate has been removed from the molding die and transferred to another location, so dirt and dust accumulate during this transfer17, reducing the yield rate. It was the cause.

These are factors that directly affect production costs and the like when attempting to carry out labor-based production, and measures to improve them have been sought.

Means for Solving the Problems> The present inventors have conducted research in order to solve the above-mentioned drawbacks of the conventional method regarding the manufacturing method of optical discs, and have finally completed the present invention. . That is, the method for manufacturing an optical disc according to the present invention uses a transfer material having a multilayer structure including a metal thin film layer and an adhesive layer as essential components,
The present invention is characterized in that the metal thin film layer and the adhesive layer are transferred onto the surface of the optical disc substrate in a mold at the same time as or immediately after molding the optical disc substrate.

Hereinafter, the configuration of the present invention will be explained in detail.

First, the transfer material used in the present invention will be explained.

In principle, the transfer material according to the present invention can be used by applying transfer materials conventionally used for various decorations. Basically, a transfer material having a multilayer structure including a metal thin film layer and an adhesive layer as essential components is used. If necessary, a protective layer, an anchor layer, a colored pattern layer, or the like may be formed for the metal thin film layer.

Next, one embodiment of the transfer material will be described in more detail.

Examples of the transfer material include those in which a release layer, a colored pattern layer, a metal thin film layer, and an adhesive layer are sequentially formed on a base sheet.

Examples of the substrate sort include single films or composite films such as polyester films, polyethylene films, polypropylene films, and nylon films. This substrate sort must have a size equal to or larger than the optical disk substrate. When the substrate sort has poor mold releasability, a release layer may be formed on its surface.

Examples of the resin component constituting the 741 delamination include acrylic resin, urethane resin, and melamine resin. This release layer may also appear on the top layer after transfer as a protective layer. In this case, the protective layer formation step for protecting the metal 7iJ film layer, which is necessary in the conventional method, is performed, that is, after forming a gold r% thin film layer on the optical disc substrate, the layer is coated with a spray method, a printing method, etc. This eliminates the need for a complicated process of forming a protective layer by a method or the like. Therefore, this has very excellent effects in terms of improving production efficiency and the rate of non-defective products.

The colored pattern layer provided as necessary is the above-mentioned 4? , lI
It is formed entirely or partially on a base sheet having release properties. In the case of music compact discs, this colored pattern layer is multi-colored, for example, the track name and disc name are in red ink, the artist name and disc manufacturer name are in green ink, and the image design appropriate for the disc is By using inks of three colors: red, yellow, and blue, the degree of freedom in design is increased, and a variety of colors can be expressed, making it possible to obtain an optical disc with high commercial value. Examples of resin components that form and constitute such a colored pattern layer include acrylic resins, polyester resins, polyamide resins, vinyl resins, urethane resins, and the like.

Next, the metal thin film layer, which is one of the essential components in the transfer material according to the present invention, is formed by depositing silver, aluminum, nickel, tellurium, etc. on the releasable base sheet or by coloring it by vacuum evaporation, sputtering, etc. It is formed on the pattern layer so as to cover the entire surface or at least a portion corresponding to the required size of the optical disc substrate surface. This step of forming the metal thin film layer can be easily performed on a long base sheet, and therefore can be processed as a subsequent step.

Next, the adhesive layer, which is one of the essential components in the transfer material according to the present invention, is formed to cover the metal 71 film layer, but it is preferably as thin as possible and has high adhesive strength. However, this adhesive layer mainly has the function of holding the metal thin film layer on the optical disc substrate. As the resin constituting the adhesive layer, epoxy resin,
Examples include acrylic resins, polyester resins, urethane resins, vinyl resins, and others.

In addition, for the optical disc which is a product after the transfer, this adhesive layer also has an important function as a protective coating layer for the recording holes of the optical disc. For example, in the case of compact discs, the recording hole size of PCM is usually 0.11μ deep.
m, length 0.9 to 3.3 μm, medium 0.5 μm,
The adhesive layer in contact with the optical disk substrate needs to be large enough to precisely follow the sides of the recording holes and to cover the necessary areas.

Next, specific means for forming a metal thin film layer or the like on the surface of an optical disc substrate using the transfer material will be explained.

In the present invention, a functional metal thin film is formed on the surface of the optical disc substrate by transferring a metal thin film layer etc. provided on the transfer material simultaneously with or immediately after molding the optical disc substrate. be.

Here, "simultaneously with molding" means that the transfer material is placed in a predetermined position between the molding molds, the molds are closed, and the molten resin is injected into the molding mold at the same time as the optical disk substrate is molded. This refers to the process of fixing and transferring a metal thin film layer or the like onto the surface of an optical disc substrate.

In addition, "immediately after molding" means that the optical disc substrate is first molded, and after the optical disc substrate is solidified, the mold for molding is opened, and then the transfer material is immediately applied to the surface of the optical disc substrate inside the mold. It refers to fixing and transferring a metal thin film layer, etc. to a surface. That is, after closing the molding die and injecting molten resin to mold the optical disk substrate, the mold is opened, and in that state, the transfer material is placed in a predetermined position between the molds, and the mold is re-injected. This refers to the process of fixing and transferring a metal thin film layer or the like onto the surface of an optical disc substrate by closing the disc and applying heat and pressure.

Next, examples according to the present invention will be given and explained.

<Example 1> A polyester film is used as the base sheet, and on top of it are sequentially a release layer and protective layer made of acrylic resin, a colored pattern layer made of vinyl resin, an anchor layer made of thermosetting urethane resin, A transfer material was constructed by providing an aluminum vacuum-deposited layer and an adhesive layer made of an acrylic vinyl resin.

The transfer material was set in a compact disc injection molding machine equipped with a scraper, and after positioning, the mold was closed and polycarbonate resin molten at 300°C was injected into the cavity to perform heating and pressure molding. After that, the mold was opened, the molded product was taken out, and the base sheet was subjected to II & tl to obtain a compact disc on which the colored pattern layer, the aluminum vacuum adhesion layer, etc. were fixed and transferred.

<Example 2> A polyester film is used as the g-body sheet, and a release layer/protective layer made of urethane resin, a tellurium vacuum adhesion layer, and an adhesive layer made of acrylic vinyl resin are sequentially provided thereon. A transfer material was constructed.

As in Example 1, the transfer material was set in an optical disc injection molding machine equipped with a stand bar, and after positioning, the mold was closed and polycarbonate resin molten at 300°C was injected into the cavity. 13++ After hot-pressure molding, open the mold, take out the molded product, and sort the substrate? , 11, the tellurium vacuum-deposited layer is fixed/
A transferred optical disc was obtained.

<Example 3> A transfer material was constructed by using a polyester film as a base sheet, and sequentially providing thereon a release layer/protective layer made of an acrylic resin, an aluminum vapor deposited layer, and an adhesive layer made of a vinyl resin.

Immediately after molding an optical disc substrate made of polycarbonate resin using an I11 molding machine for optical discs equipped with a stun gun, the transfer +1 was set in the caddy section, and the positioned molding machine was pressed again. After closing the thin I and transferring to the optical disc substrate using the mold giving force and the temperature of the molding resin, the mold is opened and the molded product is removed by peeling off the base sheet and the aluminum and laminate vapor deposited layers are removed. (fixed)
: Obtained an optical disc.

<Effects of the Invention> Since the present invention relates to a method for manufacturing a disc having the configuration described above, it has the following effects. That is, since the functional metal thin film layer is formed on the surface of the optical disc holder +1 at the same time as or immediately after the molding of the optical disks J and I using a transfer method,
It has extremely high production efficiency. Furthermore, since the process of forming the functional metal thin film layer is carried out inside the mold in which the optical disk substrate is molded, there is extremely little risk of dirt or dust adhering to it, and the yield rate is extremely high. be. Furthermore, since the formation of the three metal film layers on the surface of the optical disc substrate can be achieved through a simple transfer process, continuous production of metal thin film formation is possible, and the entire system is extremely suitable for mass production.

Therefore, the method for manufacturing an optical disc according to the present invention has high production efficiency and good product rate, and is suitable for mass production, and has extremely high industrial utility value.

Claims (1)

Scope of Claims: (1) Using a transfer material having a multilayer structure containing a metal thin film layer and an adhesive layer as essential components, the metal thin film layer and adhesive layer are formed simultaneously with or immediately after molding the optical disc substrate. A method for manufacturing an optical disc, characterized in that the above-mentioned optical disc is transferred onto the surface of the optical disc substrate in a mold. (2) The step of transferring a metal thin film layer and an adhesive layer onto the surface of the optical disk substrate in a molding mold at the same time as molding the optical disk substrate includes the following steps (a) to (d). A method for manufacturing an optical disc according to claim 1. (a) A step of positioning the transfer material at a predetermined position between the molding dies. (b) Step of closing the molding die. (c) A step of injecting molding resin. (d) Opening the molding die. (3) Immediately after molding the optical disc substrate, the step of transferring a metal thin film layer and an adhesive layer onto the surface of the optical disc substrate in a molding mold includes the following steps (a) to (f). A method for manufacturing an optical disc according to claim 1, characterized in that: (a) Step of closing the molding die. (b) A step of injecting molding resin. (c) Opening the mold for molding. (d) A step of positioning the transfer material at a predetermined position between the molding dies. (e) Close the mold again. (f) Opening the molding die.