JPS6358698B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing information recording carriers such as audio records and video disk information files.

(Conventional structure and its problems) In recent years, audio records, video discs,
Ultraviolet curing resins are widely used in the production of information recording carriers such as information files.

Hereinafter, with reference to FIG. 1, a conventional method of manufacturing an information recording carrier as described above will be explained.

In FIG. 1, reference numeral 1 denotes a stamper on which signals, recording grooves, etc. are recorded in an uneven shape. 2 is a backing material that maintains the flatness of the stamper 1;
Glue it to the back of the 3 is a disc-shaped transparent substrate. 4 is the center boss, stamper 1 and transparent substrate 3
position them concentrically. 5 is an ultraviolet curing resin applied circumferentially on the stamper 1, and a transparent substrate 3
The shape recorded on the stamper 1 is transferred onto the stamper.

In the conventional example above, first, stamper 1 is 200~
Since it is as thin as 300 μm, a backing material 2 is bonded to the back surface and reinforced to maintain flatness. Next, an ultraviolet curing resin 5 is applied concentrically with the signal track of the stamper 1. Then, the transparent substrate 3 is lowered in the direction of arrow a while being guided by the center boss 4, and the ultraviolet curing resin 5 is rolled. Thereafter, the transparent substrate 3 and the ultraviolet curing resin 5 are integrated by irradiation with ultraviolet rays to produce an information recording carrier.

However, the method described above has the disadvantage that the ultraviolet curable resin 5 flattens after being applied, resulting in a large contact area when the transparent substrates 3 are stacked, which tends to entrain air and generate bubbles.

In addition, as a method to reduce the initial contact area between the substrate and the ultraviolet curing resin during stacking, there is
53-116105. However, since this method deforms the substrate, it is effective for easily deformable plastic substrates with a diameter of 300 mm and a thickness of 1.2 mm. In reality, the substrate can hardly be deformed. Furthermore, it is difficult to apply this method to substrates with high rigidity such as glass substrates.

(Objective of the Invention) In view of the above-mentioned drawbacks, the object of the present invention is to provide a method for manufacturing an information recording carrier that can form a recording film layer on a transparent substrate without easily generating bubbles.

(Structure of the Invention) In order to achieve this object, the method for manufacturing an information recording carrier of the present invention involves applying an ultraviolet curing resin in a circumferential manner onto a horizontally installed transparent substrate, and applying the ultraviolet curing resin in a circumferential manner onto a horizontally installed transparent substrate. It is characterized in that it is installed with a gap above the stamper, is lowered while tilting, is superimposed on the stamper, and the ultraviolet curable resin is allowed to fall, and the ultraviolet curable resin and the transparent substrate are integrated. It is something.

According to this method, after the transparent substrate is turned over, the ultraviolet curing resin hangs down from the transparent substrate in an icicle shape, so the initial contact area between the ultraviolet curing resin and the stamper becomes smaller during stacking, and air is trapped. This makes it possible to overlay the transparent substrate on the stamper without any defects, and it is easy to obtain a good information recording carrier free of defects caused by bubbles.

(Description of Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory diagram of the method for manufacturing an information recording carrier of the present invention, in which 6 is a dispenser for discharging ultraviolet curable resin, 7a is a contact start point when the ultraviolet ray curable resin 5 and stamper 1 are superimposed, 8
1 is an ultraviolet irradiation lamp, and the other parts are the same as in Fig. 1.

In the manufacturing method of the present invention, first, as shown in FIG. Apply in a circular pattern. For a transparent substrate with a diameter of 130 mm, 1.5 to 2.2 g of this ultraviolet curing resin will be applied to a diameter of 55 mm.
Apply in a circumferential manner at a position of ~φ65mm. Next, as shown in FIG. 2B, the transparent substrate 3 is turned over and brought close to the stamper 1. Then, as shown in FIG. 2C, while tilting the transparent substrate 3, it is superimposed on the stamper 1 and the ultraviolet curing resin 5 is rolled. Finally, as shown in FIG. 2D, the ultraviolet curable resin 5 is cured by irradiating ultraviolet rays with an ultraviolet irradiation lamp 8, and the ultraviolet curable resin 5 and the transparent substrate 3 are integrated to produce an information recording carrier.

As described above, in the present invention, since the transparent substrate 3 is overlaid on the stamper 1 after being turned over, the ultraviolet curable resin 5 hangs down in an icicle shape, and the contact area between the ultraviolet curable resin 5 and the stamper 1 is reduced during overlapping. , it is possible to overlay the transparent substrate 3 on the stamper 1 without getting air involved, and the ultraviolet curing resin gradually spreads from the initial contact point.
A good information recording carrier without defects due to air bubbles can be easily obtained. Experimental results show that conventionally about 30% of the air bubbles with a diameter of about 0.1 mm were mixed in, but after adopting this method, no air bubbles were found to be mixed in.

Figure 3 shows a specific example of superimposing a transparent substrate coated with an ultraviolet curable resin and a stamper in the manufacturing method of the present invention. Mechanism, 1
Reference numeral 1 denotes an arm rotatable around a fulcrum 9, which holds the transparent substrate 3 and is lowered by a vertical mechanism 10.
Other details are the same as in Figure 1. The transparent substrates 3 coated with the ultraviolet curing resin 5 are turned over, held by the arms 11, and stacked on top of each other by the vertical mechanism 10 while adjusting the speed. The descending speed of the vertical mechanism 10 is set to be low in the vicinity where the contact start point 7a and the contact end point 7b contact the stamper 1 when the ultraviolet curing resin 5 and the stamper 1 come into contact, and to be high in the middle thereof.

As described above, by setting the descending speed of the transparent substrate 3 to a low speed only near the contact start point 7a and the contact end point 7b where air bubbles are likely to occur during overlapping, and setting it to a high speed in the middle, it is possible to This allows superimposition in a short time.

FIG. 4 shows an example of applying an ultraviolet curable resin onto a transparent substrate in the manufacturing method of the present invention. Apply so that the amount applied is small. In this way, contact starting point 7
By setting the amount of coating near a small, the ultraviolet curable resin 5 flows toward the contact starting point 7a due to the inclination of the transparent substrate 3 during stacking, and the ultraviolet curable resin 5 from the transparent substrate 3 flows after rolling. This can prevent the amount of protrusion from becoming uneven.

It goes without saying that the present invention can be applied not only to the above-mentioned replication process but also to the bonding of substrates together, such as the bonding of protective covers.

(Effects of the Invention) As described above, the present invention includes applying an ultraviolet curable resin in a circumferential manner onto a transparent substrate placed horizontally, and placing the transparent substrate upside down on a stamper with a gap therebetween. After rolling the ultraviolet curable resin by lowering it while tilting and superimposing it on the stamper, the ultraviolet curable resin is cured by irradiation with ultraviolet rays, and the ultraviolet curable resin and the transparent substrate are integrated, thereby recording. The present invention provides a method for manufacturing high-precision information recording carriers easily, in a short time, without creating bubbles that cause signal dropouts, and without being restricted by the material or size of the substrate. The practical effects are significant.

In addition, since the ultraviolet curable resin is first applied from above onto the transparent substrate and then turned over, it is easy to adjust the total amount of ultraviolet curable resin applied and the amount applied depending on the application location. It can be done easily and quickly.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional method for manufacturing an information recording carrier, Fig. 2 is an explanatory diagram of a method of manufacturing an information recording carrier according to the present invention, and Fig. 3 is an explanatory diagram of a method of manufacturing an information recording carrier according to the present invention. FIG. 4 is an explanatory view of an embodiment in which a transparent substrate and a stamper are superimposed, and FIG. 1... Stamper, 2... Backing material, 3... Transparent substrate,
4... Center boss, 5... Ultraviolet curing resin, 6... Dispenser, 7a... Contact start point, 7b... Contact end point, 8... Ultraviolet irradiation lamp, 9... Fulcrum, 10... Vertical mechanism, 11... Arm.

Claims (1)

[Claims] 1. A transparent substrate placed horizontally is coated with an ultraviolet curable resin in a circumferential manner, and the transparent substrate is placed upside down with a gap above a stamper, and the stamper is lowered while being tilted. A method for producing an information recording carrier, which comprises stacking the ultraviolet curable resin on top and rolling the ultraviolet curable resin, and then irradiating ultraviolet rays to cure the ultraviolet curable resin, thereby integrating the ultraviolet curable resin and the transparent substrate. 2. A method for manufacturing an information recording carrier according to claim 1, in which the descending speed at the time of overlapping is changed. 3. The method for producing an information recording carrier according to claim 2, wherein the descending speed is set low at the start and end of contact between the ultraviolet curable resin and the stamper during stacking, and set at a high speed during the process. 4. The method for manufacturing an information recording carrier according to claim 1, wherein the amount of the ultraviolet curable resin applied is reduced on the lower side of the inclination of the transparent substrates that are tilted during stacking.