JPH01243254A - Manufacture of information recording medium - Google Patents

Abstract

PURPOSE:To perform adhering joint by preventing bulge and a projection (bur) from being brought into contact with a receiving jig when the bulge and the projection are formed on a resin substrate and without being affected by the influence of them by performing the welding joint by using the receiving jig in which a clearance part for the bulge and the projection is secured at the time of manufacturing an information recording medium. CONSTITUTION:A hole part 13 is provided in the center of the resin substrate 11 of the recording medium, and an inner peripheral side non-recording area 14 and an outer peripheral side non-recording area 15 are set at the outside of the edge part of the hole part 13 and the inside of the outer edge part of the substrate 11, respectively, and a recording layer 16 is provided between the inner and the outer areas 14 and 15. Also, a resin film 12 is constituted of a flexible film in the center of which a hole part 17 is formed, and the film 12 is superposed on the surface of the substrate 11 at a recording layer 16 side, and the substrate 11 is arranged so that it can confront with the jig 20 between a sealer 19 for thermal welding having a ring shape projection part 18 and a disk shape receiving jig 20. And the thermal welding joint of the film 12 is already performed in the area 14 of the substrate at the inner peripheral side, therefore, no bulge and projection are formed on the outer edge part of the substrate 11 arranged on the jig 20.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a method for manufacturing an information recording medium. More specifically, the present invention relates to a method of manufacturing an information recording medium in which a disc-shaped resin film is fused and bonded to a disc-shaped resin substrate.

[Technical Background of the Invention] In recent years, information recording media using high energy density beams such as laser beams have been developed and put into practical use. This information recording medium is called an optical disc, and includes video discs, audio discs, large-capacity still image files, and large-capacity computer discs.
It can be used as memory.

The basic structure of an optical disk is a disc-shaped transparent resin substrate made of plastic or the like, and a recording layer provided thereon. The surface of the substrate on which the recording layer is provided is coated with an undercoat layer or an intermediate layer made of a polymeric material in order to improve the flatness of the substrate, improve the adhesion with the recording layer, and improve the sensitivity of the optical disc. Sometimes it is provided.

The recording layer of the information recording medium as described above is susceptible to the influence of the outside world, and therefore needs to be protected from the outside world for practical purposes.

In order to solve the above-mentioned problems, a technique has been proposed in which a disc-shaped resin film functioning as a protective film is bonded to the side of the substrate provided with the recording layer by a heat fusion method or the like. (example,
JP-A No. 51-75523).

By the way, resin substrates for information recording media are generally manufactured by a molding method such as injection molding. According to the inventor's study, due to the second reason in the structure of the molding die, the resin substrate obtained by molding has a high height along the outer peripheral edge on the side opposite to the side where the recording layer is provided. Approximately 10-100g
It has been found that the bulges and protrusions (m) are often formed unevenly.

FIG. 3, which was accompanied by the present inventor, is a diagram showing the relationship between the height and the distance from the outer periphery of a bulge or protrusion formed on the outer periphery of a resin substrate, as measured by the present inventor. As shown in FIG. 3, the bulge 31 extends approximately 11 JJ from a distance of approximately 1.5 mm from the outer peripheral edge of the resin substrate to the outer peripheral edge.
- m, and the protrusion (paris) 32 is formed at a height of about 357 tm at the outer peripheral edge.

It has also been found that protrusions are sometimes formed on the periphery of the hole in the center of the resin substrate formed by punching.

When an optical disc is manufactured using a heat fusion method using a resin substrate with bulges or protrusions formed on the outer periphery,
It has been found that this tends to result in optical discs that do not exhibit the expected characteristics. After further consideration of this problem, the inventor of the tree discovered that
It has been found that unexpected contact between a substrate having bulges or protrusions and a receiving jig hinders stable production of optical disks.

Here, based on the attached Figure 4, we will explain the problem when heat-sealing a resin film to a resin substrate that has non-uniform bulges or protrusions (burrs) formed on the outer periphery as described above. do.

In FIG. 4, the resin substrate 41 has a hole 43 in the center, and an inner non-recording area 44 and an outer non-recording area 44 are located outside the periphery of the hole 43 and inside the outer periphery of the resin substrate 41, respectively. An area 45 is set, and a recording layer 46 is provided between the inner and outer non-recording areas. resin film 4
2 is a flexible film provided with a hole 47 in the center.

The resin film 42 is superimposed on the surface of the recording layer 46 of the four resin substrates, and is placed between the sealer 48 for heat fusion and the receiving jig 49 so as to face the sealer 48.

The resin substrate 41 has uneven bulges and protrusions (
Paris) 50 has been formed.

In the figure, the resin film 42 has already been heat-sealed and bonded in the non-recording area 44 on the inner peripheral side of the resin substrate 41. To fuse and bond the resin film 42 in the unbonded outer non-recording area 45, the heated sealer 48 is lowered and the position of the resin film 42 corresponding to the outer non-recording area 45 of the resin substrate 41 is bonded. It is done under pressure.

Here, if uneven bulges or protrusions (burrs) 50 are formed along the outer peripheral edge of the resin substrate 41 close to the non-recording area 45 on the outer peripheral side that is pressurized by the sealer 48, the sealer 48 The pressure applied to the resin film 42 by 48 is not uniform. Therefore, the strength of the fusion bonding of the resin film 42 to the resin substrate 41 becomes uneven, and uneven bonding is likely to occur. Therefore, the resin substrate 4 of the resin film 42
There is a problem that peeling from 1 is likely to occur.

A protrusion may be formed on the periphery of the hole in the center of the resin substrate formed by punching, and the same problem occurs in this case as well.

It is not easy to obtain a resin substrate with almost no bulges or protrusions by molding, and in order to obtain such a resin substrate, special consideration must be given to the molding conditions, which increases manufacturing costs. Therefore, it becomes disadvantageous.

[Object of the Invention] An object of the present invention is to provide a method for manufacturing an information recording medium in which a resin substrate and a resin film are bonded well.

[Summary of the Invention] The present inventor has focused on the influence of bulges and protrusions on the fusion bonding of a resin substrate and a resin film, and as a result of conducting studies, the present invention has been accomplished. reached.

That is, the present invention provides an area between the inner non-recording area and the outer non-recording area, which has a hole in the center and the recording layer is set outside the periphery of the hole and inside the outer periphery, respectively. On the surface of the recording layer side of the disc-shaped resin substrate provided on the
Flexible disk-shaped resin films with a hole in the center are stacked one on top of the other, and the resin substrate is held between a fusion sealer having a ring-shaped convex portion and a disk-shaped receiving jig. A method for producing an information recording medium, in which the resin film is placed on the jig side, and the resin film is fused and bonded to the outer non-recording area and the inner non-recording area of the resin substrate using a sealer for fusion. The disc-shaped receiving jig has a radius smaller than that of the resin substrate so that its outer peripheral edge is located inside the outer peripheral edge of the disc-shaped substrate disposed thereon. and a method of manufacturing an information recording medium characterized by using a receiving jig having a radius corresponding to the non-recording area on the outer peripheral side of the resin substrate.

Preferred embodiments of the above invention are as follows.

(1) The above information characterized in that a receiving jig is used, the radius of the outer peripheral edge of which is within a range of 0.2 to 2 mm smaller than the radius of the disc-shaped resin substrate. A method for manufacturing a recording medium.

(2) The information recording medium described above, characterized in that the fusion bonding is performed using a receiving jig in which a groove with a depth of 100 gm or more is formed at a position corresponding to the peripheral edge of the hole in the resin substrate. manufacturing method.

(3) The method for manufacturing the information recording medium described above, characterized in that the resin substrate and the resin film are fused and bonded by a thermal fusion method or an ultrasonic fusion method.

Further, the present invention provides an area between an inner non-recording area and an outer non-recording area, which have a hole in the center and the recording layer is set outside the periphery of the hole and inside the outer periphery, respectively. A flexible disc-shaped resin film with a hole in the center is superimposed on the recording layer side surface of a disc-shaped resin substrate provided in The resin substrate is placed between the sealer and the receiving jig so that the resin substrate is on the side of the receiving jig, and a sealer is used for fusing the resin film in the outer non-recording area and the inner non-recording area of the resin substrate. A method of manufacturing an information recording medium by fusion bonding using the above-mentioned receiving jig, wherein a groove is formed at a position corresponding to the outer peripheral edge of a disk-shaped resin substrate placed on the receiving jig. There is also a method for manufacturing an information recording medium using a receiving jig.

A preferred embodiment of the invention described in item 1 is as follows.

(1) The method for manufacturing an information recording medium as described in item 2, characterized in that the depth of the groove formed in the receiving jig is 1100 pL or more.

(2) The information recording medium described above, characterized in that the fusion bonding is performed using a receiving jig in which a groove with a depth of 10,071 m or more is formed at a position corresponding to the peripheral edge of the hole in the resin substrate. Production method.

(3) The method for manufacturing the information recording medium described above, characterized in that the resin substrate and the resin film are fused and bonded by a thermal fusion method or an ultrasonic fusion method.

DETAILED DESCRIPTION OF THE INVENTION Representative aspects of the invention will now be described in detail with reference to the accompanying FIGS. 1 and 2. FIG.

FIG. 1 is a diagram for explaining an example of a method for manufacturing an information recording medium according to the invention described at the beginning.

In FIG. 1, the resin substrate 11 has a hole 13 in the center, and an inner non-recording area 14 and an outer non-recording area 14 are located outside the periphery of the hole 13 and inside the outer periphery of the resin substrate 11, respectively. An area 15 is set, and a recording layer 16 is provided between the inner and outer non-recording areas. Resin film 1
2 is a flexible film with a hole 17 in the center.

The resin film 12 is superimposed on the surface of the resin substrate 11 on the recording layer 16 side, and the resin substrate 11 is held between a sealer 19 for heat sealing having a ring-shaped convex portion 18 and a disk-shaped receiving jig 20. It is arranged so as to face the tool 20. In FIG. 1, the resin film 12 has already been heat-sealed and bonded in the non-recording area 14 on the inner peripheral side of the resin substrate 11. As shown in FIG.

The resin substrate 11 placed on the receiving jig 20 has uneven bulges and protrusions 21 formed on its outer peripheral edge. However, the disk-shaped receiving jig 20 has a radius smaller than the radius of the resin substrate 11 so that its outer peripheral edge is located inside the outer peripheral edge of the disk-shaped resin substrate 11 placed thereon. have. The dimension A shown in FIG. 1 is the dimension of the relief from the outer peripheral edge of the resin substrate. It is preferable that the dimension of A is usually in the range of 0.2 to 2 mm.

Therefore, the protrusions 21 of the resin substrate 11 are connected to the receiving jig 2.
0 and is not affected by bulges or protrusions 21 during heat fusion.

The radius of the receiving jig 20 is smaller than the radius of the outer peripheral edge of the resin substrate 11, but has a radius that is approximately concave with the outer diameter of the ring-shaped convex portion 18 of the sealer 19 for fusion. Therefore, the receiving jig 20 can uniformly receive pressure from the ring-shaped convex portion 18 of the heated sealer 19 at a position corresponding to the non-recording area 15 on the outer circumferential side. Therefore, the resin film 12 is well fused and bonded to the resin substrate 11 without any uneven bonding.

Further, the receiving jig 20 has a hole 1 in the center of the resin substrate 11.
Since the groove 22 is formed at a position corresponding to the peripheral edge of the resin substrate 11, fusion bonding can also be performed satisfactorily in the non-recording area 14 on the inner peripheral side of the resin substrate 11.

The cross-sectional shape of the groove is not particularly limited, and may be square, 7-shaped, or 0.
You can list things that are shaped like letters.

Next, referring to FIG. 2, the other invention will be explained. In FIG. 2, the superimposed resin substrates, resin films, and sealer for heat sealing are the same as those shown in FIG. 1. That is, in FIG. 2, a disk-shaped resin substrate 1
A flexible disc-shaped resin film 12 is superimposed on the surface of the recording layer 16 side of the recording layer 1, and this is placed between a sealer 19 for fusing having a ring-shaped convex portion 18 and a disc-shaped receiving jig 23. The resin substrate 11 is placed on the receiving jig 23 side. Next, the resin film 12 is pressed in the non-recording area of the resin substrate 11 by the ring-shaped convex portion 18 of the sealer 19 which generates heat for fusion, and is fused and bonded.

In FIG. 2, the resin film 12 has already been heat-sealed and bonded in the non-recording area 14 on the inner peripheral side of the resin substrate 11. As shown in FIG.

The resin substrate 11 placed on the receiving jig 23 has uneven bulges and protrusions 21 formed on its outer peripheral edge. However, the disk-shaped receiving jig 23 has bulges and protrusions (
A groove 24 is formed at a position corresponding to and around the outer peripheral edge of the disc-shaped substrate 11 where the bulge 21 is formed, and this groove 24 secures a so-called relief groove for a bulge or protrusion. ing.

Generally, the depth of the groove formed in the receiving jig is 1100J.
It is preferable that it is L or more.

The dimension B shown in FIG. 2 is the dimension of the relief from the outer peripheral edge of the resin substrate. The dimension of B is usually 0.2 to 2 mm
It is preferable that it is within the range of .

As described above, since the escape groove is formed, the bulges and protrusions 21 of the resin substrate 11 do not come into contact with the receiving jig 20 and are not affected by thermal fusion. Then, when the ring-shaped convex portion 18 of the heated sealer 19 presses the resin film 12 at a position corresponding to the non-recording area 15 on the outer peripheral side of the resin substrate ii to fusion-bond the resin film 12, the receiving jig 23 , it is possible to uniformly receive pressure from the ring-shaped protrusion of the sealer 18. Therefore, the resin film 12 is well fused and bonded to the resin substrate 11 without any uneven bonding.

Furthermore, the receiving jig 23 is attached to the center hole 1 of the resin substrate 11.
Since the groove 25 is formed at a position corresponding to the peripheral edge of the resin substrate 11, good fusion bonding can also be performed in the non-recording area 14 on the inner peripheral side of the resin substrate 11.

Note that, although the example of the method for manufacturing an information recording medium explained in FIGS. 1 and 2 is in accordance with the present invention, it is not limited to the above example.

For example, in the method for manufacturing an information recording medium of the present invention,
The resin film may be fused and bonded to the resin substrate by an ultrasonic fusion method. Alternatively, either the inner or outer fusion bonding may be performed separately first.

As the substrate, recording layer, and film constituting the information recording medium of the present invention, any publicly known substrates, recording layers, and films other than those that are characteristic of the present invention can be used, and these will be briefly described below.

First, the resin substrate used in the present invention can be arbitrarily selected from various resin materials conventionally used as substrates for information recording media. optical properties of the substrate,
In terms of flatness, processability, handling, stability over time, and manufacturing cost, examples of substrate materials include acrylic resins such as cell cast polymethyl methacrylate, injection molded polymethyl methacrylate, and polymethyl acrylate; polychloride resins; Preferred examples include vinyl chloride resins such as vinyl and vinyl chloride copolymers; epoxy resins; amorphous polyolefin resins; and synthetic resins such as polycarbonate. Among these, preferred are polymethyl methacrylate, polycarbonate, and epoxy resin in terms of dimensional stability, transparency, and flatness.

The surface of the substrate on which the recording layer is provided has improved flatness,
An undercoat layer (and/or intermediate layer) may be provided for the purpose of improving adhesive strength and preventing deterioration of the recording layer.

Examples of materials for the undercoat layer (and/or intermediate layer) include polymeric substances such as polymethyl methacrylate, acrylic acid/methacrylic acid copolymer, nitrocellulose, polyethylene, chlorinated polyolefin, polypropylene, and polycarbonate; silane cups; Examples include organic substances such as ring agents; and inorganic substances such as inorganic oxides (SiO2, Au203, etc.) and inorganic fluorides (MgF2).

Examples of materials used for the recording layer include Te, Zn, I
n, Sn, Zr, Au, Ti, Cu, Ge, Au, Pt
metalloids such as Bi, As, and Sb; semiconductors such as Si; and alloys thereof or combinations thereof.

Compounds such as sulfides, oxides, borides, silicon compounds, carbides, and nitrides of these metals, semimetals, or semiconductors; and mixtures of these compounds and metals can also be used in the recording layer. Alternatively, combinations of dyes, dyes and polymers, and dyes and the aforementioned metals and metalloids can also be used.

The recording layer may further contain various known metals, semimetals, or compounds thereof as recording layer materials.

The recording layer can be formed of the above-mentioned materials directly on the substrate or via an undercoat layer by methods such as vapor deposition, sputtering, ion blasting, and coating. The recording layer may be a single layer or a multilayer, but its layer thickness is generally in the range of 100 to 5,500×, preferably in the range of 150 to 100×, in view of the optical density required for optical information recording.

Note that the surface of the substrate opposite to the side on which the recording layer is provided is coated with an inorganic substance such as silicon dioxide, tin oxide, or magnesium fluoride in order to improve scratch resistance and moisture resistance.
A thin film made of a polymeric substance such as a thermoplastic resin or a photocurable resin may be provided by a method such as vacuum deposition, sputtering, or coating. Furthermore, the recording layer may be provided in a fused portion other than the recording area.

The material of the disc-shaped resin film is acrylic resin,
Examples include thermoplastic resins such as vinyl chloride resin, polystyrene resin, polyamide resin, polyolefin resin (eg, polypropylene, polyethylene), polycarbonate, polyester resin, and polyvinylidene chloride. There is no particular limitation on the material as long as it can be well fused to the substrate by ultrasonic fusion and thermal fusion. For the purposes of the invention, it is particularly preferred to use the same material as the substrate material. Further, the thickness of the resin film is in the range of 10 to 500 gm, and the preferable range is 5 gm.
It is 0 to 200 JLm.

[Effects of the Invention] The method for manufacturing an information recording medium of the present invention performs fusion bonding using a receiving jig in which a so-called relief portion of a bulge or protrusion is secured. Then, bulges and protrusions (
bulges and protrusions (
This allows fusion bonding to be performed without contacting the receiving jig and being affected by it.

Therefore, according to the method for manufacturing an information recording medium of the present invention, the resin substrate and the resin film can be fused and bonded evenly and satisfactorily. Further, in the information recording medium manufactured according to the present invention, the recording characteristics of the recording layer are stable over a long period of time.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are diagrams for explaining an example of the method for manufacturing an information recording medium of the present invention. FIG. 3 is a diagram showing the relationship between the height and the distance from the outer peripheral edge of a bulge or protrusion formed on the outer peripheral edge of the resin substrate. FIG. 4 is a diagram for explaining a conventional method of manufacturing an information recording medium. 11.41: Disc-shaped resin substrate 12.42: Disc-shaped resin film 13.17.43.47: Hole 14.44: Inner circumference side non-recording area 15.45: Outer circumference side non-recording area 16.46: Recording Layer 18: Ring-shaped convex portion 19.48: Sealer for heat fusion 20.23.49: Receiving jig 21.50: W ramiya protrusion (Paris) 22.24.25: Groove Patent applicant Fuji Photo Film Co., Ltd. Company representative Patent attorney Yasushi Yanagikawa Man-made ecstatic music (Created by country C)

Claims (1)

[Claims] 1. A disc-shaped disc having a hole in the center, and a recording layer provided in an area between an inner non-recording area and an outer non-recording area, which are set outside the periphery of the hole and inside the outer periphery, respectively. A flexible disc-shaped resin film with a hole in the center is superimposed on the surface of the recording layer side of the resin substrate, and this is coated with a sealer for fusing having a ring-shaped convex part and a disc-shaped receiver. The resin substrate is placed between the jig and the receiving jig side, and the resin film is applied to the outer non-recording area and the inner non-recording area of the resin substrate using a sealer for fusing. A method for manufacturing an information recording medium by fusion bonding, wherein the disc-shaped receiving jig is arranged such that its outer peripheral edge is located inside the outer peripheral edge of a disc-shaped substrate disposed thereon. has a radius smaller than that of the resin substrate, and
A method of manufacturing an information recording medium, comprising using a receiving jig having a radius corresponding to a non-recording area on the outer peripheral side of a resin substrate. 2. A disc-shaped disc having a hole in the center, and a recording layer provided in an area between an inner non-recording area and an outer non-recording area, which are set outside the periphery of the hole and inside the outer periphery, respectively. A flexible disc-shaped resin film with a hole in the center is superimposed on the surface of the recording layer side of the resin substrate, and this is combined with a sealer for fusing and a receiving jig having a ring-shaped convex part. In between, the resin substrate is placed on the receiving jig side, and the resin film is fused and bonded using a sealer for fusion in the outer non-recording area and the inner non-recording area of the resin substrate. A method of manufacturing an information recording medium, wherein the receiving jig is a receiving jig in which a groove is formed at a position corresponding to the outer peripheral edge of a disk-shaped resin substrate placed thereon. A method for manufacturing an information recording medium characterized by: