JPH02236832A - Information recording medium and its production - Google Patents

Abstract

PURPOSE:To obtain excellent durability by directly jointing a resin film which covers a dye recording layer with a disk-type resin substrate at the outer and inner circumferences where no information is recorded. CONSTITUTION:The recording layer 20 comprising dyes which can be read out or written in with laser light is formed on the disk resin substrate 11 having a center hole 17. The dyes on the area around the center hole 17 and the outer circumference of the substrate 11 are removed of to leave as nonrecording areas 18 and 19. Then a flexible resin film 12 having a center hole 13 is stacked on the recording side of the substrate and jointed with the substrate on the inner nonrecording area 18 and outer nonrecording area 19. Thus, the obtd. medium has excellent durability.

Description

[Detailed description of the invention] [Field of invention] The present invention relates to an information recording medium.

More specifically, the present invention relates to an information recording medium in which a disc-shaped resin film is 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.
A vine used as memory.

The basic structure of an optical disk is a disk-shaped substrate made of glass, synthetic resin, etc., and a Bi. Sn
, In, Te, or other metal or metalloid; or a cyanine-based, metal complex-based, or quinone-based dye. Note that an intermediate layer made of a polymeric substance is usually provided on the surface of the substrate on the side where the recording layer is provided, in order to improve the flatness of the substrate, improve the adhesive force with the recording layer, or improve the sensitivity of the optical disc. often.

Writing and reading information to and from an optical disc is usually performed by the following method.

Information is written by irradiating this optical disk with a laser beam, and the irradiated portion of the recording layer absorbs the light, causing a local temperature rise, causing physical or chemical changes (for example, bit generation). information is recorded by changing its optical properties. Information is also read by irradiating the optical disk with a laser beam, and the information is reproduced by detecting reflected or transmitted light depending on changes in the optical characteristics of the recording layer.

Furthermore, since the recording layer is easily influenced by the outside world, it is necessary to protect it from the outside world. As an optical disc having such an excellent protection function for the recording layer, an optical disc having an air sandwich structure has been known. However, the air sandwich structure optical disk has many disadvantages in the manufacturing process, such as high cost and many complicated steps. For this reason, in recent years, a technology has been developed to bond a disk-shaped protective resin film to the side of the substrate where the recording layer is provided.
This method is disclosed in Japanese Utility Model Publication No. 9-36339, Japanese Utility Model Application Publication No. 175427/1983, and the like.

As described above, metals, dyes, and the like are known as recording materials forming the recording layer of such information recording media. Information recording media using dyes have advantages in the characteristics of the information recording media themselves, such as higher sensitivity compared to recording materials such as metals, and they also have the advantage of being able to easily form five recording layers using a coating method. It has the above major advantages. However, when the above protective film is bonded to a substrate having a dye recording layer, the following problems arise.

A recording layer made of a dye is generally formed by coating and drying as described above. The application method is
Since it is necessary to form a uniform thin film on a disk-shaped resin substrate, it is generally applied using a spin coater. When a dye layer forming coating liquid for forming a dye layer is applied onto the substrate, it is usually applied to almost the entire surface of the substrate. Due to its characteristics, the spin coater starts coating at the inner circumferential side of the substrate.
Although it is possible to apply from a certain limited position, it is not possible to control the application range on the outer circumference side. Moreover, the coating start position on the inner circumferential side cannot be said to be coated on the inside of that position, and the dye layer forming coating liquid is coated on almost the entire surface of the substrate.

The protective resin film is bonded onto the dye recording layer on the inner circumferential side and the outer circumferential side of the substrate. Bonding is generally performed using an adhesive, heat fusion, ultrasonic fusion, or the like. According to the studies of the present inventors, when the material of the recording layer is not a metal but a dye as described above, the dye adheres to the bonding parts on the inner and outer circumferential sides of the substrate to which the resin film is bonded. Therefore, it has become clear that there is a problem in that the adhesive strength obtained by the above-mentioned bonding does not reach practical strength.

Therefore, an information recording medium in which a dye recording layer and a resin film are bonded on a substrate cannot be said to have sufficiently excellent durability.

[Object of the Invention] An object of the present invention is to provide an information recording medium with excellent durability without deterioration of initial recording and reproducing characteristics even when used or stored for a long period of time.

Specifically, an object of the present invention is to provide an information recording medium to which a protective resin film is bonded, the adhesive strength of which is sufficient for practical use.

[Summary of the Invention] The present invention has a hole in the center, and a recording layer made of a dye is set outside the periphery of the hole and inside the outer periphery. A flexible disc-shaped resin film with a hole in the center is placed on the recording layer side surface of a disc-shaped resin substrate provided in an area other than the non-recording area, on the inner and outer periphery sides of the resin substrate. an information recording medium comprising a non-recording area covered by direct bonding on the substrate surface; and; A step of providing a recording layer made of a dye that can read and/or write information with a laser by coating on a disc-shaped resin substrate having a hole in the vicinity of the periphery of the hole and the outer periphery of the substrate. A step of removing the dye recording layer in the vicinity to provide an inner non-recording area and an outer non-recording area in which the substrate surface is exposed outside the periphery of the hole and inside the outer periphery, respectively. , and a step of bonding a flexible disc-shaped resin film with a hole in the center onto the substrate on the recording layer side at the non-recording areas on the inner circumferential side and the outer circumferential side of the resin substrate, respectively. A method for manufacturing an information recording medium, comprising: a disk-shaped resin substrate having a hole in the center; and an inner non-recording area set outside the periphery of the hole from outside to the outer peripheral side. , a step of providing by coating a recording layer made of a dye that can read and/or write information with a laser, and removing the dye recording layer near the outer periphery of the substrate to form a layer inside the outer periphery. A step of providing a non-recording area on the outer circumferential side in which the surface of the substrate is exposed, and on the substrate on the recording layer side, a flexible disc-shaped resin film with a hole in the center is provided on the inner circumference side and outer circumference of the resin substrate. A method of manufacturing an information recording medium, comprising the steps of: joining each other in the non-recording areas on the sides.

Preferred embodiments of the information recording medium of the present invention are as follows.

1) The thickness of the above-mentioned tree film is 0.01 to 0.3 mm.
The above-mentioned information recording medium is characterized in that it is in the range of.

2) The information recording medium, wherein the resin film is at least one type of resin film selected from the group of acrylic resin, vinyl chloride resin, epoxy resin, polycarbonate resin, amorphous polyolefin, and polyester.

3) The information recording medium, wherein at least one surface of the resin film has minute irregularities.

4) The information recording medium, wherein the joint portion is formed in a discontinuous ring shape.

5) The information recording medium, wherein the resin substrate is at least one resin selected from the group of polycarbonate, polyolefin, polymethyl methacrylate, and epoxy resin.

Preferred embodiments of the method for manufacturing an information recording medium of the present invention are as follows.

1) The method for manufacturing the information recording medium, wherein the coating is performed using a spin coater.

2) The method for manufacturing the information recording medium, wherein the joining is performed by thermal fusion or ultrasonic fusion.

[Effects of the Invention] The resin film covering the dye recording layer of the present invention is directly bonded to the substrate to which no dye or the like is attached at the inner circumferential side and outer circumferential side of the disk-shaped substrate.

Therefore, the adhesive strength at the joint between the resin film and the disk-shaped substrate is extremely high, and there is almost no peeling even when used or stored for a long period of time.

Therefore, since the information recording medium of the present invention can maintain the protective function of protecting the recording layer from dust and the like over a long period of time, it can be said that it is an information recording medium with improved durability.

[Detailed Description of the Invention] Basically, as described above, the information recording medium of the present invention includes a disc-shaped resin substrate, a recording layer formed on the resin substrate, and a recording layer made of a dye.
In order to protect the recording layer, the recording layer is composed of resin films bonded to the inner and outer circumferential sides of the substrate.

Conventionally, there has been a problem in that when a protective resin film is bonded onto the dye recording layer at the inner and outer peripheral sides of the substrate as described in Bof, the adhesive strength is not sufficient.

Regarding this problem, according to the inventors' investigation, when the material of the recording layer is not a metal but a dye as described above, the bonding of the inner and outer circumferential sides of the substrate to which the resin film is bonded It was found that dye was attached to the parts, and as a result, the adhesive strength obtained by the above bonding did not reach practical strength.

That is, the dye recording layer is generally coated using a spin coater because it is necessary to form a uniform thin film on the disk-shaped resin substrate. Application using a spin coater is
As mentioned above, due to its characteristics, it is usually performed on almost the entire surface of the substrate. Therefore, the dye recording layer is provided on almost the entire surface of the substrate.

In order to protect this dye recording layer, a resin film is placed on the inner circumferential side (outside the hole periphery) and outer circumferential side (
(inner side of the outer peripheral edge). However, dyes (and in some cases dust) are attached to the inner and outer sides of the substrate, and the substrate and resin film are bonded through or in the presence of this dye. . In such bonding, it cannot be said that the substrate and the resin film are directly bonded, and the bonding area cannot be said to be sufficient. Therefore, it was found that in such a bonded state, the adhesive strength did not reach practical strength.

Therefore, the information recording medium of the present invention solves the above-mentioned drawbacks, and the tree film is directly bonded to the inner and outer surfaces of the tree substrate. That is, the disk-shaped resin substrate is provided with a hole in the center, a recording layer made of a dye is provided in an area other than the inner non-recording area and the outer non-recording area in which a recording layer made of a dye is set. A flexible disk-shaped resin film with a hole in the center is directly bonded to the surface of the recording layer side of the resin substrate in the non-recording areas on the inner and outer circumferential sides of the resin substrate. It is characterized by

As a result, the adhesive strength at the joint between the resin film and the disk-shaped substrate is extremely high, and there is almost no peeling even when used or stored for a long period of time.

Therefore, since the information recording medium of the present invention can maintain the protective function of protecting the recording layer from dust and the like over a long period of time, it is possible to obtain an information recording medium with improved durability.

The invention will now be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show typical embodiments of the information recording medium of the present invention. The information recording medium 10 of the present invention is formed by bonding a disc-shaped resin film 12 to a disc-shaped resin substrate 1l.

FIG. 1 shows an information recording medium 10 of the present invention on a tree film 1.
2 is a plan view seen from the side where the parts 2 and 2 are joined.

The resin film 12 has a hole 13 in the center, and a bonding area 1 on the inner peripheral side in an area corresponding to the non-recording area of the resin substrate 11.
4 and a bonding region 15 on the outer peripheral side are formed and bonded. The bonding in the bonding region l4 on the inner circumferential side is performed by a plurality of elongated island-like bonding portions 16 formed at substantially the same intervals and having substantially the same spacing.

As described above, it is preferable that at least one of the bonding areas is formed in a discontinuous ring shape such as the bonding area on the inner peripheral side. This prevents the resin film from expanding even if there is a change in external pressure. Further, in the bonding area 15 of the present invention, there is no dye or the like which is the material of the recording layer, and the resin substrate 1l and the tree film 1 are not present.
2 are directly joined.

FIG. 2 is an enlarged cross-sectional view of the information recording medium 10 of the present invention taken along line I-1 in FIG.

The disc-shaped resin substrate 11 has a hole 17 in the center, and an inner non-recording area 18 and an outer non-recording area 19 are set outside the periphery of the hole 17 and inside the outer periphery, respectively. A recording layer 20 made of a dye is formed between the non-recording areas on the inner circumferential side and the outer circumferential side.

The disk-shaped resin film 12 is bonded to form a bonding area 14 in a non-recording area 18 on the inner circumferential side of the resin substrate 11, and also forms a bonding area 15 in a non-recording area 19 on the outer circumferential side of the resin substrate 11. and are joined together. Since the resin film has appropriate irregularities on its surface, a space 22 is formed between the substrate above the recording layer and the tree film. As described above, it is preferable that the resin film has appropriate irregularities on at least one surface by embossing or the like, since this facilitates the formation of the space 22. This is effective for diffusing vaporized gas, etc., which is necessary when forming bits and the like.

The information recording medium of the present invention is obtained by bonding a resin substrate and a resin film as described above, and the bonding method is as follows:
Examples include an ultrasonic fusion method, a heat fusion method, and a method using an adhesive.

The information recording medium of the present invention basically has the above structure and can be manufactured as follows.

That is, the method for manufacturing an information recording medium of the present invention is carried out, for example, as follows. This will be explained in detail with reference to the attached FIGS. 3, 4, and 2.

FIG. 3 shows a disc-shaped resin substrate 31 with a hole 37 in the center.
, a recording layer 3 made of a dye provided thereon by coating.
0 and a partially uncoated region 33 near the periphery of the hole. A coating liquid for forming a dye recording layer is applied onto the disk-shaped resin substrate 31 using a spin coater to form a recording layer 30 made of a dye. The area of the uncoated region 33 varies depending on the conditions at the time of coating.

Generally, the innermost clamp area of the substrate, which is used to fix the substrate to the clamp of the rotary drive motor during recording and reproduction, is coated with dye to prevent it from adhering. When the coating method is performed using a roll coater other than a spin coater, dipping, etc., this uncoated area 33 usually does not exist.

FIG. 4 shows a disc-shaped resin substrate 41 with a hole 47 in the center.
, a recording layer 4 made of a dye provided thereon by coating.
0 is a sectional view consisting of an inner non-recording area 4B provided at the peripheral edge of the hole 20 and an inner non-recording area 49 provided inside the outer peripheral edge. The substrate surface is exposed by removing the dye coating layer 30 near the periphery of the hole 40 in FIG. 3 and near the outer periphery of the substrate, and outside the periphery of the hole 40 in FIG. An inner non-recording area 48 and an outer non-recording area 49 each having a surface of the substrate are provided inside the outer peripheral edge. The above dye coating layer can be removed by wiping it off before drying, wiping it off with a solvent after drying, spraying a solvent in a straight line before or after drying, or burning it with a laser after drying. There are several ways to remove it.

In addition, the surface of the inner peripheral side non-recording area 48 of the substrate is located outside the peripheral edge of the hole 40 and inside the outer peripheral edge of the hole 40 in FIG.
As another method of providing the outer non-recording area 49,
The following method can be used. When coating the dye recording layer forming coating liquid on the substrate, the non-recording area 4 on the inner peripheral side of the substrate
8, and apply to the outside of this (other inclined castles) using the Subin coat method or the like. Therefore, since the inner non-recording area 48 of the substrate is obtained, the dye recording layer only needs to be removed in the outer non-recording area 49. In order to secure the non-recording area 48 on the inner peripheral side of the substrate, that is, to prevent dye from adhering to this area, when applying the subin coat, the discharge amount is set to 5 g/sec or less and the rotation speed is 30 Or.
It is necessary to satisfy coating conditions such as performing coating at pm or higher. In this way, by controlling the conditions for applying the dye, removal of the dye can be omitted only from the outer circumferential side.

The following FIG. 2 is the same as the above-mentioned FIG. 2, but will be referred to again in order to explain the resin film bonding process. Second
In the figure, a disc-shaped resin substrate 1 with a hole 17 in the center
1. An inner non-recording area l8 and an outer non-recording area 19 are set outside the periphery of the hole 17 and inside the outer periphery, respectively. In between, a layer 20 made of a dye is formed. Further, the disc-shaped resin film 12 is connected to the resin substrate 11.
A bonding area 14 is formed in the non-recording area 18 on the inner circumferential side of the resin substrate 11 to form a bonding area 14, and a bonding area 15 is formed in the non-recording area 19 on the outer circumferential side of the resin substrate 11 for bonding.

The resin film 12 is bonded to the inner non-recording area 44 and the outer non-recording area 45 of the substrate in FIG. 4, where the surface of the substrate is exposed by removing the dye coating layer 30 in FIG. 3. Examples of the bonding method include an ultrasonic fusion method, a heat fusion method, and a method using an adhesive. Preferably,
Ultrasonic fusion method or heat fusion method. Furthermore, it is preferable to join the inner circumferential side by ultrasonic welding and the outer circumferential side by thermal welding. In order to form the above-mentioned joined part into a discontinuous ring shape, a heat fusion machine equipped with a heater block having a ring-shaped convex part or an ultrasonic welding machine equipped with an application horn having a ring-shaped convex part is used. It is preferable to use

For example, the information recording medium of the present invention with excellent durability can be manufactured as described above.

The information recording medium of the present invention can be manufactured using, for example, the materials described below.

The plastic substrate used in the present invention can be arbitrarily selected from various materials used as substrates for conventional information recording media. Examples of substrate materials include cell-cast polymethyl methacrylate, injection molded polymethyl methacrylate, and other acrylic resins from the viewpoint of substrate optical properties, flatness, workability, handling, stability over time, and manufacturing costs. Examples include vinyl chloride resins such as vinyl chloride and vinyl chloride copolymers; epoxy resins; polycarbonate resins, amorphous polyolefins, and polyesters. Preferably, mention may be made of polycarbonate, polyolefin and cell cast polymethyl methacrylate.

The resin film used in the present invention includes acrylic resin such as polymethyl methacrylate; polyvinyl chloride;
Examples include vinyl chloride resins such as vinyl chloride copolymers: epoxy resins, polycarbonate resins, amorphous polyolefins, and polyesters.

The surface of the substrate on which the recording layer is provided has improved flatness,
An undercoat layer may be provided for the purpose of improving adhesive strength, improving solvent resistance of the substrate, and preventing deterioration of the recording layer. Examples of materials for the undercoat layer include polymethyl methacrylate,
Acrylic acid/methacrylic acid copolymer, styrene/maleic anhydride copolymer, polyvinyl alcohol, N-methylolacrylamide, styrene/sulfonic acid copolymer,
Styrene/vinyltoluene copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate/vinyl chloride copolymer, ethylene/vinyl acetate copolymer, polyethylene, polyvinyl chloride, Polymer substances such as carbonates; organic substances such as silane coupling agents; and inorganic oxides (SiO2, AIL203, etc.)
, inorganic substances such as inorganic fluoride (MgF2).

The undercoat layer is formed by, for example, dissolving or dispersing the above substances in a suitable solvent to prepare a coating solution, and then applying this coating solution to the substrate surface using a coating method such as spin coating, dip coating, or extrusion coating. can do. The layer thickness of the undercoat layer is generally 0.005 to 20
It is in the range of μm, preferably in the range of 0.01 to 10 μm.

Further, a pregroup layer and/or a prebit layer may be provided on the substrate (or undercoat layer) for the purpose of forming tracking grooves or irregularities representing information such as address signals. The material for the pregroup layer etc. is at least one type of acrylic acid monoester, diester, triester, and tetraester.
or oligomer) and a photopolymerization initiator can be used.

The pregroup layer is formed by first coating a mixture of the above-mentioned acrylic ester and polymerization initiator on a densely formed matrix (stamper), and then placing the substrate on top of this coating layer. Then, the liquid layer is cured by irradiation with ultraviolet rays through the substrate or the matrix, thereby fixing the substrate and the liquid phase.

Next, by peeling the substrate from the matrix, a substrate provided with a pregroup layer is obtained. The thickness of the pregroup layer generally ranges from 0.05 to 100 μm, preferably from 0.1 to 50 μm. As in the present invention,
If the substrate material is plastic, the pregroups and/or prebits may be provided directly on the substrate by injection molding, extrusion molding, or the like.

Below, a recording layer made of a dye is provided on the blank substrate (or pregroup layer, etc.). The dye used in the present invention is not particularly limited, and any dye may be used. For example, cyanine dyes, lidocyanine dyes, biryllium/thiobilylium dyes, azulenium dyes, squarylium dyes, metal complex dyes with Ni, Cr, etc., naphthoquinone/anthraquinone dyes, indophenol dyes, Examples include indoaniline dyes, triphenylmethane dyes, triallylmethane dyes, aluminum/diimmonium dyes, and nitroso compounds.

Margins Below Among these, dyes with a high absorption rate for light in the near-infrared region of 700 to 900 nm are preferred, since semiconductor lasers that emit near-infrared light have been put to practical use as recording and reproducing lasers.

Preferred examples thereof include: i) Cyanine dye: [1] ((:H3) 2N- (CIl.GH)s-
CH-”N(Cll3)2Cj2 04-N(CH3)
2 ”N((:113)2 [3] (:- C I1 - C I1 - C H - (
: (However, R is a hydrogen atom or N(C113)2) [4] Φゝ -L 2平 (X埠-), 7m (However, Φ and Taira each have an aromatic ring condensed therein.) Good indolenine ring residue, thiazole ring residue, oxazole ring residue, selenazole ring residue, imidazole ring residue,
pyridine ring residue, thiazolopyrimidine ring residue or imidazoquinoxaline ring residue, L is a linking group for forming monocarbocyanine, dicarbocyanine, trivalent lupocyanine or tetracarpocyanine, Xa
``1 is an m-valent anion, m is 1 or 2,
Zarani Xa- is Φ, Shimaka! Examples of specific compounds represented by the above general formula include Examples include the following a) to h).

CH3 Cll3 ctto4- CILO. -Cl04- ii) Squarylium dye: C(CH:+)* 〇1C(CI*)3 iii) Azulenium dye: RI (However, R1 and R2 R2 and R 3 R3 and R
4 R 4 and R% R! i and R6 and R6 and R7
When at least one of the combinations forms a ring of substituted or unsubstituted heterocycles or aliphatic rings, and does not form the ring}jl R2R 3 R4
RS R6 and R7 are each a hydrogen atom, a halogen atom, or a few organic residues, or Rl and R
2 R 3 and R4 R4 and R S R 5 and R6
and at least one combination of R6 and R7 may form a substituted or unsubstituted aromatic ring,
A is a divalent organic residue linked by a double bond,
Z1 is an anionic residue. Note that at least one carbon atom constituting the azulene ring may be replaced with a nitrogen atom to form an azaazulene ring. 》iv) Indophenol dye: A-R' Y child) (However, X and Y are each a hydrogen atom, an alkyl group, an acylamino group, an alkoxy group, or a halogen atom, and R I B 2 and R3 are A hydrogen atom, C, -C2, substituted or unsubstituted alkyl group, aryl group, heterocycle or cyclohexyl group, and A is 1NHCO- or 100N+1-) ■》Metal complex dye : (However, R1 to R4 are each an alkyl group or an aryl group, and M is a transition metal atom with just a few transition metal atoms (however, R1 and R2 are each an alkyl group or a halogen atom, and M is a transition metal atom with just a few (However, R1 and R2 are each a substituted or unsubstituted alkyl group or aryl group, and R3 is an alkyl group, a halogen atom, or a R4 -N-R1' group (wherein R4 and R5 are each substituted or unsubstituted alkyl group or aryl group. substituted alkyl or aryl group)
, M is a transition metal atom, and n is an integer from 0 to 3) (However, [CaL] is a cation necessary to make the complex salt neutral, and M is a transition metal atom of Ni, Cu, CO , Pd or pt, and n is 1 or 2) (However, X is a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group, n is an integer of 1 to 4, and A is a quaternary ammonium group) (However, ([:at] is a cation necessary to make the complex salt neutral, and M is a Ni
, Cu, CO, Pd or pt, and n is 1 or 2
) (However, x1 and x2 are a nitro group and /
or a halogen atom, n1 and n2 are each an integer of 1 to 3, and R1 and R2 are each an amino group, a monoalkylamino group, a dialkylamino group, an acetylamino group, or a benzoylamino group (including a substituted benzoylamino group). ), X' and X2, n+ and n2, and R1 and R2 may be the same or different from each other, M is a Cr or Co atom, Y is hydrogen,
(sodium, potassium, ammonium, aliphatic ammonium (including substituted aliphatic ammonium), or alicyclic ammonium) vi) Naphthoquinone-based, anthraquinone-based dye: R H (However, R is a hydrogen atom, an alkyl group, an allyl group, (R is a hydrogen atom, an alkyl group, an allyl group, an amino group or a substituted amino group) (R is a hydrogen atom, an alkyl group, an allyl group, an amino group or a substituted amino group) substituted amino group) (wherein, X is a halogen atom) ONII20 ON11. Examples include S.

Note that these dyes may be used alone or as a mixture of two or more. Furthermore, when a cyanine dye is used, the metal complex dye or the aminium/diimmonium dye described above may be used together as a quencher.

The recording layer can be formed by dissolving the dye and, if desired, a binder in a solvent to prepare a coating solution, then applying this coating solution to the surface of the substrate to form a coating film, and then drying the coating solution. can.

Examples of the solvent for preparing the dye coating solution include esters such as ethyl acetate, butyl acetate, and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone; halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, and chloroform; Ethers such as tetrahydrofuran, ethyl ether, and dioxane; alcohols such as ethanol, n-probanol, isopropanol, and n-butanol; amides such as dimethylformamide; Examples include solvents. Note that these non-hydrocarbon organic solvents may contain hydrocarbon solvents such as aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents, as long as the amount is within 50% by volume. .

The coating solution also contains antioxidants, UV absorbers, plasticizers,
Various additives may be added depending on the purpose.

When a binder is used, examples of the binder include cellulose derivatives such as gelatin, nitrocellulose, and cellulose acetate, natural organic polymer substances such as dextran, rosin, and rubber; and carbonized materials such as polyethylene, polypropylene, polystyrene, and polyisobutylene. Hydrogen resins, vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride/polyvinyl acetate copolymers, acrylic resins such as polymethyl acrylate, polymethyl methacrylate,
Synthetic organic polymer substances such as polyvinyl alcohol, chlorinated polyolefins, epoxy resins, butyral resins, rubber derivatives, and initial condensates of thermosetting resins such as phenol-formaldehyde resins can be mentioned.

Examples of the coating method include a spray method, a spin coat method, a dip method, a roll coat method, a blade coat method, a doctor roll method, and a screen printing method.

When a binder is used as a material for the recording layer, the ratio of dye to binder is generally 0.01 to 99% (weight ratio).
It is preferably in the range of 1.0 to 95% (weight ratio).

The recording layer may be a single layer or a multilayer, but the layer thickness is generally 0.
．． It is in the range of Ol~10μm, preferably 0.02~
It is in the range of 1 μm. Furthermore, the recording layer may be provided not only on one side of the substrate but also on both sides.

A reflective layer may be provided on the dye recording layer. By providing a reflective layer, in addition to the effect of improving reflectance, it is possible to obtain the effects of improving S/N during information reproduction and improving sensitivity during recording.

The light-reflective substance that is the material of the reflective layer is a substance that has a high reflectance to laser light, and examples include Mg, S
e%Y, Ti%Zr, Hf, V, Nb% Ta, Cr%
Mo, W, Mn, Re, Fe, Co, Ni, Ru, R
h, Pd% I r, Pt% Cu%Ag%Au, Zn
%Cd%AIL,Ga,In%Si,Ge,Te%P
Mention may be made of metals and metalloids such as B, Po, Sn, and Bi. Among these, preferred are Au, A
g% Cu, Pt, AfL, Cr and Ni. These substances may be used alone, or in combination of two or more or as an alloy.

The reflective layer can be formed on the recording layer by, for example, vapor deposition, sputtering, or ion-blating the above-mentioned light-reflective material.

The layer thickness of the reflective layer is generally in the range of 100 to 3000X.

A protective layer may be provided on the reflective layer for the purpose of physically and chemically protecting the recording layer and the entire information recording medium. This protective layer also has the effect of increasing scratch resistance and moisture resistance on the side of the substrate where the recording layer is not provided.

Examples of materials used for the protective layer include inorganic substances such as SiO, Si02, SIN4, MgF2, and Sn02.
etc. can be mentioned. Furthermore, examples of the organic substance include thermoplastic resins, thermosetting resins, UV curable resins, etc., and preferably υV curable resins.

The thickness of the protective layer is generally in the range of 0.1 to 100 μm.

In addition to the above, the protective layer can be formed, for example, by laminating a film obtained by extrusion of plastic onto the dye recording layer via an adhesive layer.

Alternatively, it may be provided by methods such as vacuum deposition, sputtering, and coating.

Examples and comparative examples of the present invention are described below. However, these examples do not limit the invention.

[Example 1] n-Gjl. Cl 04- n-C, He and the above dye with the following dye: 0.01 mol % Ig added to 2,2.3,3-
A dye recording layer coating solution (concentration: 2.75% by weight) was prepared by dissolving the dye in tetraphenyl alcohol.

Disc-shaped polycarbonate substrate with tracking guide (outer diameter: i30mm, inner diameter: 15mm% thickness:
1.2 mm, track pitch: 1.6 μm, group depth: 800X), the above coating liquid was discharged by the subin coating method at ffi7 g/sec, rotation speed 700 rp.
After coating at a speed of 2000 rp
Rotate for 1 minute at TTR and dry to a film thickness of 12,001 mm.
A recording layer was formed.

2.2, 3. on the surface of the substrate on which the dye recording layer is provided.
3-tetraph-probanol solvent is sprayed very thinly to remove the dye provided on the inner circumferential side and the outer circumferential side of the substrate, and remove the dye provided on the inner circumferential side and the outer circumferential side of the substrate as shown in Fig. 4. 1 from the periphery of the hole in the substrate, which corresponds to the recording area 48 and the outer non-recording area 49 provided inside the outer periphery.
A region was formed in which the substrate surface was exposed in a range of 0 mm outside and a range of 1.5 mm inside from the outer periphery.

As a resin film, we use a polycarbonate film (product) with minute irregularities on both sides (A side: maximum unevenness depth 7.2 μm, Ra approximately 1.6 μm, B side 2 maximum uneven depth 3.2 μm, Ra approximately 0.6 μm). Name: Mitsubishi Gas Chemical ■, Eubilon Matte Film, FE-2000MO1, 130μm)
was cut into 35 mm and outer diameter 120 mm.

The matte films were stacked concentrically on the surface of the recording layer with side A facing, and the inner circumferential side was joined by ultrasonic fusion and the outer circumferential side was bonded by heat fusion.

In this way, an information recording medium consisting of a substrate, a dye recording layer and a resin film was manufactured.

[Example 2] In Example 1, the coating liquid for forming a dye recording layer was applied by spin coating at a discharge rate of 1 g/sec and a rotation speed of 100.
A dye recording layer was formed in the same manner by coating the substrate from a position 10 mm outside the periphery of the hole at a speed of 0 rpm to the outer circumferential side.
, 3. Remove only the dye provided on the outer circumferential side of the substrate by spraying a very fine stream of 3-tetraph-probanol solvent, and remove the exposed area of the substrate surface within 1.5 mm inside the outer circumferential edge. Formed. In this way, the range is 10 mm outside the periphery of the hole in the board and 1.5 mm from the outer periphery.
A region was formed in which the surface of the substrate in the inner range was exposed.

An information recording medium was manufactured in the same manner as in Example 1 except for the above.

[Comparative Example 1] An information recording medium was manufactured in the same manner as in Example 1 except that the dye provided on the inner circumferential side and the outer circumferential side of the substrate was not removed.

[Evaluation of Information Recording Medium] 1) The state of bonding between the resin film and the substrate of the 10-hour information recording medium obtained above was observed.

3) The information recording medium obtained above was stored for 15 days (60t, 9o%RH) (7) The state of bonding between the tree JII7 ilm and the substrate was observed.

The results obtained are shown in Table 1.

Table 1 Initial bonding condition Bonding condition after 15 days Example 1 No peeling Peeling S=t, Example 2
No peeling No peeling Comparative Example 1 No peeling Almost no peeling As shown in Table 1, the bonding state between the IM film and the substrate was the same in all of the information recording media of Examples 1 and 2 and Comparative Example 1 immediately after bonding. No peeling is seen. However, it can be seen that peeling was observed in Comparative Example 1 over time.

This is considered to be because the initial bonding strength of the disk of the comparative example was lower than that of the disk of the example, and did not reach practical strength.

[Brief explanation of drawings]

FIG. 1 is a plan view of a typical information recording medium of the present invention, viewed from the side to which the resin film is bonded. FIG. 2 is a sectional view of the information recording medium taken along line II in FIG. 1. FIG. 3, FIG. 4, and FIG. 2 are cross-sectional views for explaining the method for manufacturing an information recording medium of the present invention. 1 2 : 1 3, 1 4 : 1 5 : 1 8, 1 9, 20, 2 2 : 3 3 : Disc-shaped resin film 17, 37, 47: Bonding area on the inner circumferential side of the hole, bonding area on the outer circumferential side 48 : Non-recording area 49 on the inner circumference side: Non-recording area 30, 40 on the outer circumference side: Area where recording layer space is partially uncoated

Claims (1)

[Claims] 1. A hole is provided in the center, and a recording layer made of a dye is provided in an area other than the inner non-recording area and the outer non-recording area 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 directly attached to the surface of the recording layer side of the disc-shaped resin substrate in the non-recording areas on the inner and outer periphery sides of the resin substrate. An information recording medium that is covered by bonding. 2. A step of coating a disc-shaped resin substrate with a hole in the center and forming a recording layer made of a dye that allows information to be read and/or written by a laser, near the periphery of the hole and the outer periphery of the substrate. By removing the dye recording layer in the vicinity of the hole, an inner non-recording area and an outer non-recording area are provided in which the substrate surface is exposed outside the periphery of the hole and inside the outer periphery, respectively. and a step of bonding a flexible disk-shaped resin film with a hole in the center onto the substrate on the recording layer side at the non-recording areas on the inner and outer circumferential sides of the resin substrate, respectively; A method for manufacturing an information recording medium, comprising: 3. A dye that can read and/or write information using a laser from the outside of the inner non-recording area set outside the periphery of the hole on a disc-shaped resin substrate with a hole in the center. a step of providing a recording layer by coating, a step of removing the dye recording layer near the outer peripheral edge of the substrate to provide an outer peripheral side non-recording area in which the substrate surface is exposed inside the outer peripheral edge; and a step of bonding a flexible disk-shaped resin film with a hole in the center onto the substrate on the recording layer side at non-recording areas on the inner and outer circumferential sides of the resin substrate, respectively. A method for manufacturing an information recording medium, characterized by: