JPH01256043A - Metallic mold reproduced by precision molding and its production - Google Patents

Abstract

PURPOSE:To form a substrate contg. identification information without giving damages and flaws, etc., thereto by embedding a plate recorded with the identification information as rugged patterns into the outside of the region corresponding to the information recording region of a medium. CONSTITUTION:A stamper 6 embedded with the plate 4 on which the identification information is recorded as the rugged patterns to the outside of the region corresponding to the information recording region of the optical information recording medium is produced. Such stamper 6 is produced by the process of disposing the plate on which the identification information is recorded as the rugged patterns to the outside of the region formed with the patterns of a master disk on which the rugged patterns are formed and the process of depositing a metal on the master disk by electroforming to form the metallic mold cast with the above-mentioned plate. The sharp and easy to read signals are thereby obtd. and the increase of defects in the stage of marking identification symbols on the medium is prevented.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a precision molding reproduction mold (hereinafter referred to as a stamper) necessary for making a substrate for an optical information recording medium that can be recorded, reproduced, and/or erased by a light beam. The present invention relates to a method for manufacturing the same.

[Prior art]

Conventionally, the method of writing identification information such as a serial number on an optical information recording medium is to print it on the substrate after molding the substrate or after forming a recording film using ink using a magic marker, inkjet, etc. There are two known methods: one method is to write information using a stamping machine, such as a thermal printing method.

However, in the method of printing using ink, the adhered ink smears or runs, causing problems such as contamination of the disk surface.

Furthermore, in the method of writing using a stamping machine or the like, there are problems such as an increase in defects when making scratches on the substrate and contamination of the disk surface by powder generated when making scratches.

[Summary of the invention]

An object of the present invention is to solve the problems of the prior art described above and to provide a standber and a method for manufacturing the same, which can mold a substrate for an optical information recording medium containing identification information without causing stains, scratches, etc. be.

The above object of the present invention is achieved by a standber in which a plate in which identification information is recorded as a concavo-convex pattern is embedded outside the area corresponding to the information recording area of an optical information recording medium. In addition, such a standby is manufactured by placing a plate on which identification information is recorded as a concave-convex pattern on a master disc with a concavo-convex pattern outside the area where the pattern is formed, and by electroforming the metal onto the master disc. The plate is deposited and a mold is formed into which the plate is cast.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 1(a) to 1(d) are schematic cross-sectional views showing the manufacturing process of the stand bar of the present invention.

First, as shown in FIG. 1(a), a photoresist was coated on a polished glass plate 1, exposed and developed to form a layer 2 having an uneven pattern for recording information. A thin nickel film 3 with a thickness of 500 to 2000 angstroms was formed thereon by vacuum deposition. As shown in FIG. 1(b), a nickel plate 4 having a thickness of 50 to 100 microns and having identification information recorded thereon by etching was set on this recording master. Although a nickel plate was used here, other metal plates such as copper and aluminum can also be used. Next, as shown in FIG. 1(C), a nickel layer 5 is laminated to a thickness of about 0.2 to 1 mm by nickel electroforming, and finally, as shown in FIG. 1(d), a recording master is formed. By further peeling, a stand bar 6 having identification information such as a serial number was formed.

Schematic plan views of the stand bar manufactured as described above are shown in FIGS. 2 and 3. As described above, according to the present invention, a standby 6 having identification information 12 such as a serial number in an area other than the information recording area 11 can be obtained.

Note that "outside the information recording area" means the inside or outside of the recording area.

The present invention can be modified in various ways other than the embodiments described above. For example, in the example, the plate was set after the master was subjected to conductive treatment, but first the plate was placed on the master,
A conductive layer of a metal thin film may be formed thereon by vacuum film formation.

〔Effect of the invention〕

As explained above, since the present invention embeds a plate on which identification information is recorded in a concave-convex pattern in the standber, 1) it is possible to prevent an increase in defects in the process of writing identification symbols on the medium; 2) Since the identification symbol is transferred when the substrate is molded, the process can be simplified and process control made easier; 3) The written symbol is clear and easy to read.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(d) are schematic cross-sectional views showing the steps of manufacturing a standby bar according to the present invention, and FIGS. 2 and 3 are schematic plan views showing embodiments of the standby bar according to the present invention.

Claims (2)

[Claims] (1) In a precision molding replication mold for molding the substrate of an optical information recording medium, a plate on which identification information is recorded as a concavo-convex pattern is embedded outside the area corresponding to the information recording area of the medium. A precision molding reproduction mold characterized by: (2) A process of arranging a plate on which identification information is recorded as an uneven pattern outside the area on which the pattern is formed on the master disk on which the uneven pattern is formed, and depositing metal on the master disk by electroforming. A method for manufacturing a precision molding replica mold comprising the step of forming a mold into which the plate is cast.