JPH03276436A - Production of optical recording medium - Google Patents

Abstract

PURPOSE:To shorten the time for formation and to prevent the sticking of dust by laminating required 6 layers including an electrocasting layer in the uppermost layer on a glass substrate to form an electrocasting master disk, polishing the rear surface of the master disk and blanking the disk. CONSTITUTION:A release layer 2, a protective layer 3, a resist pattern layer 4, and a conductive film layer 5 are laminated on the glass substrate 1 and further, the electrocasting layer 6 is laminated thereon. The laminated layers of the six layers are peeled from the substrate 1 to form the master disk of the electrocasting layer. The rear surface of this master disk is polished and the master disk is subjected to blanking. There is then no need for the washing drying, etc., for removing the unnecessary parts of the resist patterns before the formation of the protective layer and, therefore, the time for formation of the protective layer and, therefore, the time for formation is shortened. Since the working from the rear surface side of the electrocasting master disk is executed, the sticking of the dust on the recording surface is prevented and the optical recording medium having the high reliability is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing optical recording media such as optical discs (compact discs), video discs, and optical cards. The present invention relates to a method of manufacturing an optical recording medium that can prevent the adhesion of .

[Prior Art] Optical recording has advantages over magnetic recording in that there is no contact between the recording medium and the head, and high-density recording is possible. As this optical recording medium, there are known read-only ones, additionally writable ones, and erasable and rewritable ones. It has been put into practical use in the form of compact discs), optical video discs, optical cards, etc.

By the way, as a method for manufacturing this type of optical recording medium, the following methods have been proposed, for example.

That is, first, a resist pattern layer and a conductive film layer are formed on a glass substrate, then an electroformed layer is formed on the conductive film layer, the glass substrate and the electroformed layer are separated, and then cleaning and drying are performed. This is a method in which a protective layer is coated, the back surface is polished, and the product is manufactured by punching.

[Problems to be Solved by the Invention] However, this type of conventional optical recording medium manufacturing method has the following problems.

(a) To remove resist scum, dust from the outside air, etc.
Washing and drying steps are required, which increases production time.

(b) After the glass substrate and the electroformed master are separated, a portion of the resist remains on the glass substrate, so severe cleaning or polishing is required to recycle the glass substrate.

The present invention has been made to solve the above-mentioned problems, and it is possible to shorten manufacturing time by eliminating the need for cleaning and drying steps before forming a protective layer, and to prevent the adhesion of dust. The purpose of the present invention is to provide an extremely reliable method for manufacturing an optical recording medium.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a first step of forming a release layer on a glass substrate, a second step of forming a protective layer on the release layer. , a third step of forming a resist pattern layer on the protective layer, a fourth step of forming a conductive film layer on the resist pattern layer, and a fifth step of forming an electroforming layer on the conductive film layer. , a sixth step of peeling the electroformed master from the glass substrate, and a seventh step of polishing the back surface of the electroformed master and punching it into a finished product.

[Function] Therefore, in the method for manufacturing an optical recording medium of the present invention, cleaning and drying steps before forming the protective layer are not necessary.
The manufacturing time can be shortened accordingly. In addition, since the signal surface is always covered with a protective layer from signal formation to backside polishing and punching, reliability can be improved with less adhesion of dust. Furthermore, when a glass substrate is formed, only a simple cleaning is required because no resist or the like remains on the glass substrate due to the presence of the peeling layer.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional configuration diagram showing an example of the manufacturing process of an optical disc, which is an optical recording medium according to the present invention. The optical disc of this example is manufactured as follows.

That is, as shown in FIG. 1(a), first, a release layer 2 is formed on a glass substrate 1, and then a protective layer 3 is formed on this release layer 2. Here, as the material for the release layer 2, for example, acrylic resin, urethane resin, melamine resin, etc. can be used. Further, the thickness of the peeling layer 2 is, for example, 0.1 to 1.0 μm. On the other hand, as the material for the protective layer 3, for example, salt vinyl acetate resin, vinyl chloride resin 1, urethane resin, etc. can be used. Further, the thickness of the protective layer 3 is, for example, 5 to 100 μm.

Next, as shown in FIG. 1(b), a resist is coated on the protective layer 3 and patterned by exposure to form a resist pattern layer 4 (formation of a signal pattern). On top, a conductive film □ layer 5 is formed by vapor deposition.
form. Here, as the material of the resist pattern layer 4, for example, positive resist is used, and its thickness is, for example, 0.12 μm. On the other hand, the material of the conductive film layer 5 is, for example, nickel (Ni), silver (A
g) etc. can be used, and the thickness thereof is, for example, 0.05 to 1 μm.

Next, as shown in FIG. 1C, an electroformed layer 6 is formed on the conductive film layer 5 by electroforming. Here, as the material of the electroformed layer 6, for example, nickel (Ni) or the like can be used.

Next, as shown in FIG. 1(d), the electroformed master is peeled off from the glass substrate 1. After that, the back side of the electroformed master is polished and the finished product is punched out.

Here, as a method of polishing the back surface of the master disc, for example, the master disc may be rotated and polished with sandpaper or the like.

In the optical disc manufactured as described above,
By eliminating the need for cleaning and drying steps before forming the protective layer 3, the manufacturing time can be shortened accordingly. Furthermore, since the signal surface is always covered with the protective layer 3 from signal formation to back surface polishing and punching, the reliability of the optical disc can be improved with less dust adhesion.

Further, when the glass substrate 1 is to be regenerated, only simple cleaning is required since no resist or the like remains on the glass substrate 1 due to the presence of the peeling layer 2.

As described above, the optical disc of this embodiment includes a peeling layer 2 formed on a glass substrate 1, a protective layer 3 formed on this peeling layer 2, and a resist pattern layer 4 formed on this protective layer 3. A conductive film layer 5 is formed on this resist pattern layer 4, an electroforming layer 6 is formed on this conductive film layer 5, and after this electroformed master is peeled off from the glass substrate 1, electroforming is performed. It is manufactured by polishing the back side of a master disc and punching it out.

Therefore, the following various effects can be obtained.

(a) Since cleaning and drying steps before forming the protective layer 3 are not necessary, the manufacturing time can be shortened accordingly.

(b) Since the signal surface is always covered with the protective layer 3 from signal formation to back surface polishing and punching, it is possible to increase reliability as an optical disc with less adhesion of dust.

(c) When the glass substrate 1 is regenerated, no resist or the like remains on the glass substrate 1 due to the presence of the peeling layer 2, so only simple cleaning is required and no effort is required.

In the above embodiment, the present invention is applied to an optical disc, but the present invention is not limited to this, and the present invention can be applied to optical video discs, optical cards, and other sheet-like optical recording media in the same manner. Similar effects can be obtained by applying the invention.

[Effects of the Invention] As explained above, according to the present invention, it is possible to shorten the manufacturing time by eliminating the need for cleaning and drying steps before forming the protective layer, and to achieve extremely high reliability by preventing the adhesion of dust. A method for manufacturing an optical recording medium with high performance can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional configuration diagram showing an embodiment of the manufacturing process of an optical disc, which is an optical recording medium according to the present invention. DESCRIPTION OF SYMBOLS 1... Glass substrate, 2... Peeling layer, 3... Protective layer, 4... Resist pattern layer, 5... Conductive film layer, 6
...Electroformed layer.

Claims (2)

[Claims] (1) A first step of forming a release layer on a glass substrate, a second step of forming a protective layer on the release layer, and a third step of forming a resist pattern layer on the protective layer. , a fourth step of forming a conductive film layer on the resist pattern layer, a fifth step of forming an electroforming layer on the conductive film layer, and a step of peeling the electroformed master from the glass substrate. A method for producing an optical recording medium, comprising the steps of step 6 and step 7 of polishing the back side of the electroformed master and punching it into a finished product. (2) The method for manufacturing an optical recording medium according to claim (1), wherein the optical recording medium is in the form of a disk, a card, or a sheet.