JPH01243251A - Optical disk and its manufacture - Google Patents

Abstract

PURPOSE:To simplify the manufacturing process of an optical disk having the function of multiple color print by attaching the function of set-solid as a base to express gradation for the multiple color print on a protection layer by using a white mixed protective agent as protection liquid to form the protection film to protect the reflection film of the optical disk. CONSTITUTION:The bit shape 4 of an irregular part on which information is recorded is formed on a transparent disk substrate 1, and a signal part 4 with prescribed thickness made of aluminum is provided on the surface of the shape by using a sputtering or vapor-depositing machine. A protection ink layer 3 is coated on the signal part 4 by a spin coater. The protection ink layer 3 is constituted of the protective agent in which a white light filler is mixed, and the protection ink layer 3 is provided with the function of the set- solid as the base to express the gradation for the multiple color print, and level print 5 can be performed by the multiple color print.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an optical disc, and particularly to a protective layer thereof.

<Prior art and its problems> In general, compact disc-digital audio (C
Compact disks and optical disks such as D-DA), CI)-ROM, and CD-1, such as DRAW,
In order to identify the contents of optically readable disks such as E-DRAW and laser disks, labels are pasted or printed to indicate the contents in areas that do not interfere with signal reading. Taking a CD as an example, the content is displayed on the protective coating layer, and the manufacturer's name,
The singer's name, performer's name, performance time, etc. are printed in one color or in multiple colors.

This printing generally relies on pad printing or screen printing to avoid damaging the signal layer and to print with low printing pressure, and is mainly one- or two-color line drawings. There is.

Conventional label printing uses one color or at most two colors, as mentioned above.
Although it used to have no color gradation, color printing with gradation is now required due to the need for differentiation. In this case, the number of colors is
At least three colors are required: "yellow,""red," and "indigo J," but preferably one more color, "ink," is added to make the total four colors, as good results in terms of tone reproduction can be obtained.

However, the base of the printed surface is a reflective layer (
It has a structure in which a protective coating layer (10 μm or less) is coated on an AI thin film.Since this protective coating layer is colorless and transparent, the base of the printing surface is not white, unlike when printing on paper, but has a mirror finish. It has become.

Generally, color separation of color originals is done on the assumption that it will be printed on a white background, so if you print on anything other than a white background, the color balance will be disrupted. It was common practice to print a solid color and then print three or four colors on top of it, which was a time-consuming and troublesome process.

<Means for Solving the Problems> The present invention has been made in view of the current situation as described above, and provides a protective liquid in which a white filler is mixed with a protective liquid that forms a protective layer for protecting a reflective film. (by coating or creating it as the first color in printing), the protective layer has the function of a solid white base to express gradation for multicolor printing, and the manufacturing process is simplified. An optical disc provided with multicolor printing is provided.

<Example> Hereinafter, the present invention will be described in detail with reference to the drawings.

A compact disc is an example of an optical disc.
As shown in FIG. 1, a transparent disk substrate 1 has a concave and convex focusing shape 4 in which information is stored, and a reflective layer 2 of aluminum laminate is applied to the surface using a sputtering or vapor deposition machine.
We have established a thickness of 1000 people. A protective film 3 is usually applied to the surface of this reflective layer 2 using a spin coater using acrylic resin to prevent oxidation of the aluminum laminate and damage the information signal.
is coated. Further, label printing 5 is provided as required.

In the present invention, this protective film 3 was coated using a spin coater using an ink containing a mixture of acrylic resin and white titanium. The thickness is 10 μm, considering that it has the effect of preventing oxidation of aluminum and destruction of information signals.
I made it about m.

The ink used for this protective film is an ink that is a mixture of UV-curable acrylic resin and white titanium in an appropriate ratio.

The ink may be of an ultraviolet curing type, and the ink used for white solids may be mixed with an acrylic resin, as long as it has good suitability.

As described above, the protective layer of the present invention prevents the reflective layer 2 from being oxidized, prevents the pits of the information signal from being destroyed, and also serves as a solid white base for expressing gradations.

Further, by configuring the protective layer as a solid white screen as the first color of screen printing during label printing, the step of forming the protective layer is not necessary.

<Effects> As described above, the present invention is an optical disc that prevents oxidation of the aluminum reflective layer of the disc and destruction of information signal pits, and also serves as a solid white base for multicolor label printing. The present invention provides an excellent optical disc that maintains the same quality as above, and also has the effect of providing high-class decorative properties.

In addition, by forming the protective layer as the first color in printing, it is possible to reduce the number of steps required to form the protective layer by one, which is economically advantageous. This results in an excellent optical disc that also reduces warping.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view showing an optical disc according to the present invention. ■... Disc substrate 2... Reflective layer 3... Protective ink layer (protective film) 4...
Signal part C pit shape) 5...Label printing patent application Person Toppan Printing Co., Ltd. Representative Kazuo Suzuki Figure 1

Claims (1)

[Claims] 1) An optical disc in which pits are formed on one surface of a transparent resin layer, a metal reflective film is provided on the pits, and a protective layer and label printing are sequentially applied, the protective layer comprising: is composed of a protective agent mixed with a white filler, and the protective layer has a solid white function as a base for expressing gradation for multicolor printing, An optical disc characterized in that the label is printed in multiple colors. 2) A method for manufacturing an optical disc, characterized in that the protective layer according to item 1, which is composed of a protective agent mixed with a white filler, is spin-coated. 3) The optical disc according to item 1, wherein the protective agent is a mixture of an ultraviolet curable acrylic resin and white titanium in an appropriate ratio. 4) A method for manufacturing an optical disc, characterized in that the protective layer according to item 1, which is composed of a protective agent mixed with a white filler, is formed by printing as a solid white color as the first color of label printing.