JPH04129799A - Information recording medium and its manufacture - Google Patents

Abstract

PURPOSE:To increase the adhesive properties of the resin substrate of a protecting layer with a reflective layer by providing the protecting layer so that it comes in contact with the inner/outer peripheral lateral end parts of the substrate and on condition that the protecting layer is made of a cured compound consisting of a chemical compound having a specific polymerizable double bond with a specific layer thickness as a protecting layer. CONSTITUTION:An application liquid for forming a color recording layer is applied to a disc-like resin substrate 31 to form a recording layer 32 consisting of a color. In addition, a reflective layer 33 of metal is formed on the recording layer 32. The reflective layer 35 is provided on an area other than an inner periphery side non-recorded area 33 provided around the periphery of a perforated part of the substrate 31 of the reflective layer 35 and an inner periphery side non-recorded area 34 provided inside the outer periphery. Next, an ultraviolet curable resin application liquid is applied over the entire surface of the substrate where a recording layer 32 and the reflective layer 35 are formed. That is, a resin compound containing a compound having, at least, 5 polymerizable double bonds and a compound having 3 or 4 polymerizable double bonds and a compound having a fluorine atom or a silicon atom, is dissolved in an organic solvent to prepare an application liquid with a viscosity of 10cps or lower. If the application liquid is applied to the entire surface of the substrate where the recording layer 32 and the reflective layer 35 are formed, the color which is present in the inner periphery side non-recorded area 33 and the outer periphery side non-recorded area 34 is dissolved and removed. Then only the protecting layer is formed in these areas. The mentioned applied layer is irradiated with an ultraviolet beam to obtain a protecting layer of polymerized and cured ultraviolet beam-curable resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to an information recording medium on which information can be recorded using a high energy density laser beam, and a method for manufacturing the same.

[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 disk, and is used as a hito disk, an audio disk, a large-capacity still image file, a disk memory for a large-capacity computer, and the like.

The basic structure of photonics is a disc-shaped substrate made of glass, synthetic resin, etc., and Bi, Sn, etc.
, In, Te, or other metal or metalloid; or a cyanine-based, metal complex-based, or quinone-based dye. Information is written into the optical disk by irradiating the optical disk with a laser beam through the substrate, and the irradiated portion of the recording layer absorbs the light, causing a local temperature rise and causing physical or chemical damage. Information is recorded by altering its optical properties through changes (eg, the creation of pits). Information is also read by irradiating the optical disk with a laser beam through the substrate, and the information is reproduced by detecting reflected or transmitted light corresponding to changes in the optical properties of the recording layer.

In order to improve the durability of such information recording media,
A protective layer is provided on the recording layer, or a recording layer is provided on at least one of the two disc-shaped substrates as a TiSF structure, and this substrate is located inside the recording layer, An air sandwich structure has also been proposed in which the two are joined to form a space. Compared to the method of forming a sandwich structure, the formation of a protective layer is advantageous in that it is easier to manufacture and requires less manufacturing cost. In optical discs provided with such a protective layer or optical discs with an air sandwich structure, the recording layer is not exposed to the outside air and information is recorded and reproduced using laser light that passes through the substrate. It has the advantage that it will not be damaged physically or chemically, or that dust will not adhere to its surface and interfere with the recording and reproducing of information.

The protective layer is generally provided on the recording layer when the recording material is a metal, and on the reflective layer provided on the dye recording layer when the recording layer material is a dye. The reason why a reflective layer is provided on the dye recording layer is to avoid the problem that a recording layer made of a dye generally has a low reflectance, or that if a protective layer is formed by coating, it will be attacked by the dye or solvent. be. In other words, information recording media using dyes have advantages in terms of the characteristics of the recording medium itself, such as higher sensitivity compared to recording materials such as metals. It has the great manufacturing advantage of being able to However, the recording layer made of a dye has the above-mentioned drawbacks, and for this reason, a metal reflective layer is often provided on the dye recording layer.

Generally, a protective layer is further provided on the reflective layer for the purpose of protecting the dye recording layer and the reflective layer.

Conventionally, protective layers formed on reflective layers (in the case of recording materials or dyes) or on metal recording layers have been made using ultraviolet curable resins because they can shorten the manufacturing process and have low surface hardness. It is relatively widely used due to its high cost. As the protective layer provided on the metal recording layer, for example, a composition of urethane acrylate having a phosphate group and an acrylic monomer is disclosed in JP-A No. 60-20972, and a composition of acrylic monomer is disclosed in JP-A-61-21113. Compositions of functional acrylic monomers and fluorinated acrylic monomers, JP-A-63-30880 discloses compositions of epoxy acrylate, trimethylolpropane triacrylate, and 1,6-hexanediolycyacrylate as examples of ultraviolet curable resins. Things are being suggested.

Further, it is known that an ultraviolet curable resin is used for the protective layer formed on the reflective layer provided on the dye recording layer, for example, in JP-A-1-159842 and JP-A-2-1326.
Although it is described in Publication No. 54, its composition is not disclosed.

In an information recording medium having a dye recording layer, in which a dye recording layer, a reflective layer, and a protective layer are formed in this order on a resin substrate, unlike an optical disk having a metal recording layer, there is a difference between the resin substrate and the dye recording layer. Since both the adhesion and the adhesion between the dye recording layer and the reflective layer are not good, there is a problem that the protective layer is likely to peel off between these layers. In order to improve such adhesion, the present applicant has filed an application for an information recording medium having the structure shown in FIG.
-58972). That is, as shown in FIG.
2. An annular reflective layer 15 laminated on the recording layer so that the inner circumference side edge and the outer circumference side edge of each layer coincide, and
protection provided on the reflective layer so as to extend beyond the inner and outer edges of the reflective layer and contact the surface of the disk-shaped substrate; An information recording medium comprising 16 layers is proposed. Since this medium is formed by directly contacting the inner and outer edges of the protective layer or resin substrate, the adhesion between the substrate and the protective layer is generally relatively good, so the adhesion may be improved. It is the same thing.

However, in order to obtain even better adhesion of the protective layer, it is necessary to have even better adhesion between the resin substrate and the reflective layer, and in order to obtain fire resistance of the protective layer, a high surface It is desirable that the protective layer has excellent hardness and surface water repellency. The ultraviolet curable resins disclosed in the journal publication do not take into account the photoresistivity shown in Figure 1 at all, and even if they are used, it is difficult to obtain a protective layer with excellent adhesion. be.

[Object of the Invention] The present invention provides an information recording layer provided on a resin substrate with a dye recording layer, a reflective layer, and a protective layer, or in this order, which has a good appearance, improved durability, and excellent recording and reproducing characteristics. The purpose is to provide recording media.

Another object of the present invention is to provide an information recording medium particularly in which the protective layer has excellent adhesion to the substrate and the reflective layer.

Another object of the present invention is to provide a method for easily manufacturing the above information recording medium.

[Summary of the Invention] The present invention provides a dye recording layer provided in an annular shape on a disc-shaped resin substrate and capable of recording information using a laser, and a dye recording layer on the annular recording layer having an inner circumferential side edge of each layer. An annular reflective layer made of metal laminated so that the outer peripheral edge thereof coincides with the inner peripheral edge and the outer peripheral side edge of the reflective layer, respectively. a protective layer provided on the reflective layer so as to extend and contact the surface of the disk-shaped substrate, and the protective layer comprises a compound having at least 5 polymerizable double bonds and 3 or An information recording medium characterized in that the cured layer is obtained by polymerization with a compound having four fluorine atoms, the cured layer contains a compound having a fluorine atom or a silicon atom, and the thickness of the protective layer is less than 5 μm. It is in.

The above-mentioned information recording medium includes a step of coating a dye recording layer on which information can be recorded by laser on a disc-shaped resin substrate, a step of forming a circular reflective layer on the recording layer, and a step of forming a polymerizable double bond. A compound having at least 5 polymerizable double bonds, a compound having 3 or 4 polymerizable double bonds, and a compound having a fluorine atom or a silicon atom.An organic solvent containing at least an organic solvent capable of dissolving a resin substrate and an organic solvent capable of dissolving a dye. Applying an ultraviolet curable resin coating solution having a viscosity of 10 cps (25°C) or less dissolved in the composition, while removing the exposed portion of the dye recording layer existing in the area other than the annular reflective layer, Advantageously obtained by a method for producing an information recording medium, which comprises a step of forming a protective layer by irradiating the coating layer with ultraviolet rays after coating the reflective layer and the entire surface of the disk-shaped resin substrate. I can do it.

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

1) The weight ratio of the compound having at least 5 polymerizable double bonds to the compound having 3 or 4 polymerizable double bonds is in the range of 0.5:98 to 20:80. The above information recording medium.

2) A compound having at least 5 polymerizable double bonds,
The above information recording medium is characterized in that it is at least one selected from the group consisting of dipentaerythritol hexaacrylate, civentaewasthritol pentaacrylate, dipentaerythritol hexamethacrylate, and dipentaerythritol pentamethacrylate.

3) The information recording medium described above is a compound having a fluorine atom or a silicon atom, or a surfactant having a fluorine atom or a silicon atom.

4) An information recording medium characterized in that it is at least one type of dye selected from the above-mentioned dyes, cyanine dyes, azulenium dyes, phthalocyanine dyes, imidasoquinoxaline dyes, and schwawaum dyes.

5) The information recording medium, wherein the resin substrate is made of polycarbonate, polyolefin, or polymethyl methacrylate.

6) The material of the above reflective layer, Au, Ag, Cu, Ni, P
The information recording medium is made of at least one metal selected from the group consisting of tungsten, Cr, Ti, and Au.

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 dye layer is applied using a spin coater.

[Effects of the Invention] The information recording medium of the present invention has a structure in which the protective layer is provided in direct contact with the inner and outer edges of the substrate as described above, and a specific layer is used as the protective layer. A cured product of a composition (ultraviolet curable resin) consisting of a thick compound having a specific polymerizable double bond is used. This significantly improves the adhesion of the protective layer to the resin substrate and reflective layer, and forms an extremely durable protective layer that has excellent water repellency due to its high surface hardness and low surface energy. It can be said that it is an information recording medium that is

In addition, the method for manufacturing the information recording medium of the present invention includes applying a coating liquid for forming a protective layer with low viscosity and high solubility.
Since the protective layer can be formed without dissolving and removing excess dye on the inner and outer peripheral edges of the substrate, it can be said that this is a simple and easy manufacturing method.

[Detailed Description of the Invention] The information recording medium of the present invention has a basic configuration in which a dye recording layer, a reflective layer, and a protective layer are provided in this order on a substrate. In such a configuration, the dye recording layer is easy to manufacture and has high sensitivity, the reflective layer improves the low reflectance that is a drawback of the dye layer, and the protective layer protects the above two layers and protects the optical disc. Each of the three layers has its own role in improving the durability of the material. It is based on the idea that these parts share their respective functions.

The basic structure of the information recording medium of the present invention is shown in FIG.

FIG. 1 shows a disc-shaped resin substrate 11 with a hole 10 in the center.
, a recording layer 1 made of a dye provided on a substrate by coating
2 is a partial cross-sectional view of an information recording medium comprising a reflective layer 15 provided thereon and a protective layer 16 further provided on the reflective layer. The protective layer 16 covers the entire surface of the reflective layer 15, the inner non-recording area 13 and the outer non-recording area 14.
It covers almost the entire surface of the area. Therefore, the dye recording layer 12 and the reflective layer I5 are completely covered with the protective layer 16.

As described above, the protective layer is formed so that its inner and outer peripheral edges are in direct contact with the substrate. Therefore, the adhesion between the dye recording layer and the reflective layer and the adhesion between the reflective layer and the protective layer are significantly improved.

The ultraviolet curable resin that is the material for forming the protective layer of the present invention is composed of a compound having at least 5 polymerizable double bonds and a compound having 3 or 4 polymerizable double bonds, and further contains a fluorine atom or a silicon atom. It includes a compound having the following. In addition, the thickness of the formed protective layer is 5 μm.
less than

By using the cured product of the ultraviolet curable resin with the above layer thickness and the above composition as a protective layer, the adhesion of the protective layer to the dendrite substrate and the reflective layer is significantly improved, and the surface hardness and surface energy are low. Since it has excellent water repellency, it can be said that it is a protective layer with extremely excellent durability. Since the protective layer of the present invention is composed of 1,000 polymers having three or more polymerizable double bonds, high hardness can be obtained even if the layer is thin. It is thought that by reducing the layer thickness in this way, the concentration of stress during curing is reduced and the adhesion of the resulting protective layer to the resin substrate and reflective layer is improved.

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. 2, 3 and 1.

FIG. 2 shows a disc-shaped resin substrate 21 with a hole 20 in the center.
, a recording layer 2 made of a dye provided thereon by coating.
2 and a partially uncoated region 23 near the periphery of the hole. Disc-shaped resin substrate 21
A coating liquid for forming a dye recording layer is applied thereon using a spin cord to form a recording layer 22 made of a dye. The area of the uncoated area 23 varies depending on the conditions at the time of coating, and generally it is not possible to secure a sufficient area to improve the adhesion of the subsequent protective layer, etc.

FIG. 3 shows a disc-shaped resin substrate 31 with a hole 30 in the center.
, a recording layer 3 made of a dye provided thereon by coating.
2. A reflective layer made of metal provided in an area other than the inner non-recording area 33 provided at the periphery of the hole 30 and the inner non-recording area 34 provided inside the outer periphery. 3
5 is a partial cross-sectional view. A reflective layer 35 made of metal is formed by vapor deposition or the like on the recording layer 22 made of dye shown in FIG. At this time, the reflective layer 35 is provided in an area other than the inner non-recording area 33 provided at the periphery of the hole of the substrate 31 and the inner non-recording area 34 provided inside the outer periphery. Therefore, the vicinity of the inner and outer edges of the dye recording layer 32 is not covered with the reflective layer 35. Such a reflective layer 3
In order to secure the inner non-recording area 33 and the outer non-recording area 34, the formation of 5 is usually carried out by masking these parts and performing vapor deposition, sputter linking, or the like.

Next, the ultraviolet curable resin coating solution of the present invention is applied to the entire surface of the substrate on which the recording layer 32 and the reflective layer 35 are formed by, for example, a spin code method.

A resin composition containing a compound having at least 5 polymerizable double bonds, a compound having 3 or 4 polymerizable double bonds, and a compound having a fluorine atom or a silicon atom is dissolved in an organic solvent to obtain a viscosity of 10 cps (25 °C) Prepare the following coating solution.

The solvent used is an organic solvent composition containing at least an organic solvent capable of dissolving the resin substrate and an organic solvent capable of dissolving the dye. However, in the present invention, an organic solvent capable of dissolving the resin substrate or the dye refers to an organic solvent that can dissolve the resin substrate or the dye material.
．． It is an organic solvent that can be dissolved at a concentration of 0.1% by weight (25°C) or higher.

When such a low-viscosity, highly soluble coating liquid is applied to the entire surface of the substrate on which the recording layer 32 and the reflective layer 35 are formed by the Subi-coat method, the inner non-recording area 33 and the outer non-recording area 34 are The dye present in the area is dissolved and removed, leaving only a protective layer in this area as shown in FIG. In this manner, the coating liquid is applied to the reflective layer and the entire surface of the disk-shaped resin substrate, and then the coating layer is irradiated with ultraviolet rays to provide a protective layer formed by polymerization and hardening of the ultraviolet curable resin.

After the reflective layer is formed on the information recording medium manufactured in this way, the dye in the inner and outer areas where the reflective layer is not provided is removed, and then the protective layer is applied around the area or directly to the substrate. They are formed so that they touch each other. Therefore, it is possible to easily create an information recording medium in which the adhesion between the dye recording layer and the reflective layer and the adhesion between the reflective layer and the protective layer are significantly improved. Furthermore, since the protective layer does not come into direct contact with the dye recording layer, the dye recording layer is not attacked when the protective layer is applied, resulting in a good appearance of the resulting information recording medium, and recording characteristics such as C/N. It will be improved. Therefore, the information recording medium thus obtained has a good appearance, improved durability, and excellent recording and reproducing characteristics.

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

The resin substrate used in the present invention can be arbitrarily selected from various plastic materials used as substrates for conventional information recording media. In terms of the optical properties, flatness, processability, handling, static stability, and manufacturing cost of the substrate, examples of substrate materials include acrylic resins such as cell cast polymethyl methacrylate and injection molded polymethyl methacrylate. : Vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymers; Epoxy resins; Polycarbonate resins, amorphous polyolefins and polyesters. Preferably, mention may be made of polycarbonates, polyolefins and cell-cast polymethyl methacrylates.

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 the 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, polyhinyl alcohol, N-methylolacrylamide, styrene/vinyltoluene copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated Polymer materials such as polyolefins, polyesters, polyimides, vinyl acetate/vinyl chloride copolymers, ethylene-vinyl acetate copolymers, polyethylene, polypropylene, polycarbonates, organic substances such as carbonate linking agents, and inorganic oxides (Sin
2, Aj2203, etc.), and inorganic substances such as inorganic fluoride (MgF2).

The undercoat layer can be formed by, for example, preparing a coating solution by dissolving or dispersing the above substances in a suitable solvent, and then applying this coating solution to the substrate surface by a coating method such as a spin code, dip coat, or extrusion coat. can be formed. 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 pre-groove layer and/or a pre-pit 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 pre-croup layer etc. is at least one type of acrylic acid monoester, diester, triester and tetraester.
Alternatively, a mixture of a photopolymerization initiator and a photopolymerization initiator can be used.

To form the pre-groove layer, first, a mixed solution consisting of the above acrylic ester and a polymerization initiator was applied onto a N-dense matrix (stambar), and then a substrate was placed on top of this coating solution layer. Thereafter, 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 mother mold, a substrate provided with a pre-croup layer is obtained. The thickness of the pregroove layer is generally in the range of 0.05 to 100 μm, preferably in the range of 0.1 to 50 μm. As in the present invention,
If the substrate material is plastic, pre-croops and/or pre-pits are directly provided on the substrate by injection molding or extrusion molding (or a pre-croup layer, etc.).
A recording layer made of a dye is provided on the sheet. The dye used in the present invention is not particularly limited, and may be any of the following. For example, cyanine dyes, phthalocyanine dyes, biryllium/thiopyrylium dyes, azulenium dyes, squarylium dyes, Ni, Cr.
Examples include metal complex dyes, naphthoquinone/anthraquinone dyes, indophenol dyes, indoaniline dyes, triphenylmethane dyes, triallylmethane dyes, aluminum/diimmonium dyes, and nitroso compounds. can.

Among the stiff edges and bottoms, semiconductor lasers that emit near-infrared light have been put into practical use as recording and reproducing lasers, so they have a high absorption rate for light in the near-infrared region of 700 to 900 nm. Dyes are preferred.

Preferred examples thereof include i) cyanine dye [1] (Ctb)zN-(C:HJ:H)5-CH
＝”N(CH3)2cishi (T, n is 2 or 3) (T, R is a hydrogen atom or N(CH3)2) [4] Φ ” −L = v (X ff
1-) I/ff1 (Top, Φ and flat are aromatic rings or optionally fused indolenine ring residues, chiaturu ring residues, oxazole ring residues, selenazole ring residues, imidazole ring residues) residue, pyridine ring residue, thiazolopyrimidine ring residue or imidazoquinoxaline ring residue, L is a linking group for forming monocarbocyanine, dicarbocyanine, tricarbocyanine or tetracarbocyanine, X″′- is an m-valent anion,
m is 1 or 2; ) Specific examples of the compound represented by the above-mentioned formula include the following a) to k).

1S0-C4H5 l　S　O-C4H.

[Cl Cl0゛IO [fl [9] CIO CIO []] [kl CIO' ii) Squalium dye 1ii) Azulenium dye: (However, R1 and R2, R2 and R3, R3 and R', R'
R1, R2R3, R4, R5 when at least one of the combinations of and R5, R5 and R6, and R6 and R7 forms a substituted or unsubstituted heterocycle or aliphatic ring, and does not form a ring. , R6 and R7 are each a hydrogen atom, a halogen atom, or m organic residues, or at least the combinations of R1 and R2, A single combination may form a substituted or unsubstituted aromatic ring, A is a divalent organic residue bonded by a double bond, and Z- 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 azulene ring. ) iv) Indophenol dye: (X and Y are each a hydrogen atom, an alkyl group, an acylamino group, an alkoxy group, or a halogen atom, and R1, R2 and R3 are each a hydrogen atom, 01
~C2o is a substituted or unsubstituted alkyl group, aryl group, heterocycle or cyclohexyl group, and A is -NHC
(O- or 100NH-) ■) Metal complex dye: (R1-R4 are each an alkyl group or an aryl group, and M is a divalent transition metal atom) (wherein, R1 and R2 are each an alkyl group or a halokene atom, and M is a divalent transition metal atom) (wherein, R1 and R2 are each a substituted or unsubstituted alkyl group or aryl group, and R3 is an alkyl group, a halogen atom, or an R'N-R5 group (wherein R4 and R5 are each a substituted or unsubstituted alkyl group or aryl group), M is a transition metal atom, and n is 0 to (An integer of 3) (where, [Cat] is a cation necessary to make the complex salt neutral, M is Ni, Cu, Co, Pd or pt, and n is 1 or 2) (where, [Cat] is a cation necessary to make the complex salt neutral, M is Ni, Cu, Co, Pd, or pt, and n is 1 or 2) is a methyl group, n is an integer from 1 to 4, and A is a quaternary ammonium group) (and x2 are each a nitro group and/or a halogen atom, and R2 is each are integers from 1 to 3, R1 and R2
are amine group, monoalkylamino group, dialkylamino group, acetylamino group, hensoylamino group (
containing a substituted henshylamino group), XI and X2,
n, and R2 and R1 and R2 may be the same or different, M is a Cr or Co atom, and Y is hydrogen, sodium, potassium, ammonium, aliphatic ammonium (W-substituted aliphatic (containing ammonium) or alicyclic ammonium)vi) Naphthoquinone-based, anthraquinone-based dye (wherein, R is a hydrogen atom, an alkyl group, an allyl group, an amino group, or a substituted amino group) (Tatashi, R is a hydrogen atom, an alkyl group, an allyl group, an amino group, or a substituted amine group) (R is a hydrogen atom, an alkyl group, an allyl group, an amine group, or a substituted amine group) is an integer of ~10 ) (However, X is a halogen atom.)

Among these dyes, the method of the present invention can be preferably applied to cyanine dyes, azulenium dyes, squarylium dyes, phthalocyanine dyes, and imitazoquinoxaline dyes. Note that these dyes may be used alone or as a mixture of two or more. Further, when a cyanine dye is used, the metal complex dye or the aminium/cyinmonium 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.

Solvents for preparing the above 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, and halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, and chloroform. , tetrahydrofuran, ethyl ether, ethers such as dioxane, alcohols such as ethanol, n-furopanol, isopropanol, n-butanol, amides such as dimethylformamide, 2.2.3.3-tetrafluoropropanol Examples include fluorine-based solvents such as tools. 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. good.

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

When a binder is used, examples of the binder include cellulose derivatives such as ceratin, nitrocellulose, and cellulose acetate; natural organic polymeric substances such as dextran, rosin, and rubber; and polyethylene, polypropylene, polystyrene, and polyisobutylene. Hydrocarbon resins, vinyl resins such as polyvinyl chloride, polyvinylidene chloride, combinations of polyvinyl chloride and polyvinyl acetate, acrylic resins such as polymethyl acrylate, polymethyl methacrylate,
Examples include synthetic organic polymeric substances such as polyvinyl alcohol, chlorinated polyolefins, epoxy resins, butyral resins, rubber derivatives, and initial condensates of thermosetting resins such as phenol/formaldehyde resins.

Examples of the coating method include a spray method, a spin code method, a tip method, a roll coating method, a blade coating 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 10 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 0.01 to 10 μm, preferably 0.02 to 1
It is in the μm range. Furthermore, the recording layer may be provided not only on one side of the substrate but also on both sides.

A reflective layer is provided on the dye recording layer.

By providing a reflective layer, in addition to the effect of improving reflectance,
The effects of improved S/N ratio during information reproduction and improved sensitivity during recording can be obtained.

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 thereof include Mg, Se,
, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo
, W, Mn, Re, Fe, Co, Ni, Ru, Rh, P
d, I r, Pt, Cu, Ag, Au, Zn, Cd, A
I, Ga, In, Si, Ge, Te, Pb, Po, Sn
, Bi, and metalloid metals.

Among these, preferred are Au, Ag, Cu, and Pt.
, An, 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, depositing, sputtering, or ion-blading the above-mentioned light-reflecting substance.

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

A protective layer made of an ultraviolet curable resin is 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.

The material for forming the protective layer of the present invention includes: (1) at least one compound having at least 5 polymerizable double bonds, (2) at least one compound having 3 or 4 polymerizable double bonds, and (4) fluorine or silicon atoms. It consists of compounds that have

The weight ratio of ■a compound having at least 5 polymerizable double bonds to ■a compound having 3 or 4 polymerizable double bonds is generally in the range of 0.5:98 to 20:80 (■:■). The ratio is preferably in the range of 2:98 to 20:80, particularly preferably in the range of 3:97 to 15:85 (■:■). 0.0% for a compound containing a fluorine or silicon atom or an ultraviolet curable resin (total amount of a compound having at least 5 polymerizable double bonds and 3 or 4 polymerizable double bonds). 01-5.0
It is preferable that it is contained in a proportion of 0.0% by weight.
It is preferable that the content be 0.02 to 3.0% by weight. Furthermore, it is preferable that the photopolymerization initiator is contained in a proportion of 0.1 to 5.0% by weight based on the ultraviolet curable resin. The ultraviolet curable resin may further contain various additives such as an antistatic agent, an antioxidant, and a UV absorber depending on the purpose.

■Compounds having at least 5 polymerizable double bonds include polyfunctional urethanes with polyfunctional molecules such as dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexamethacrylate, and dipentaerythritol pentamethacrylate. (meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, etc.
Polyfunctional oligomers of meth)acrylate can be mentioned. The above-mentioned polyfunctional polymer is preferred because it provides high hardness and excellent cotton adhesion. These compounds can be used alone or in combination of two or more.

■ Compounds having 3 or 4 polymerizable double bonds include pentaerythritol tetraacrylate, tetramethylolmethanetetraacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, A-1 CH2CH2COOCH==CH2 A-2 Polymer Aronix M-315 (the above structural formula TA-1) manufactured by Toagosei Kagaku Kogyo ■, which is a functional special acrylate;
-325 (structural formula TA-2 above), Aronix M-7100, ShiM-8030, Aronix M-8060, and Aronix M-8100 manufactured by Toagosei Chemical Industry Co., Ltd., which are polyfunctional polyester acrylates. Among these, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, Aronix M-315
(Structural formula TA-1 above) and M-325 (Structural formula TA-2 above) are preferred. These compounds can be used alone or in combination of two or more, but it is preferable to use two or more in order to obtain a balance of various physical properties.

(2) The compound having a fluorine atom or a silicon atom is preferably a surfactant having a fluorine atom or a silicon atom.

Examples of surfactants containing fluorine atoms or silicon atoms include the following.

Hereinafter, S-1 fc2H, )3Si(CH2)ncOOHn=6-1
0 C6H,, (CH3) 2S engineering (CH2) 2COOHH
OOCC2H4Sl (CH3) 20 (CH3)
2SiC2H4C(X)HICH3)3SiO5i (
CH2) 25CH2COOH0cH3)3Si○]2
Si(CH3)(CH2130s03H(C4H90
)2Si(OC2H4NH2)2.2R-cOOH[1
cH3+3si○]3Si(CH2)3NN((CH2
)NH2-B [(RNR'R"), -aSx (R"') a]
(a-a) ・(4a) C1HO(C2H4C) 3S
iC2H4Coo (C2H40)3H(CH3) 3
SiC6H4QC2H40HCr 5H17Sx [o
(C2HaO) nH]3n = 1 ~ 2 n = o ~ 20 m = o ~ 20 x = 1 ~ 20 °: 0 ~ 20 χ = 1 ~ 20 -I R, COOM R (S02 N (R') 2 CH2COO
MRr B N R' C2H40SO, MR, S
O3M Rr CH20CIIH2-503M m=1
~20MO35-CHCOOCH2R.

CH2COOCH2R.

■ Rr B N C. J(2-CP(OH)
) 2R'
m=1 to 20F-12F-13F-14R, OH RfBN (CtH40), H(CH2CH).

n-1 ~20 COOCH 2R.

n=1 to 20, R represents an alkyl group containing a fluorine atom, and R. R', R'' and Rp° represent a hydrogen atom or an alkyl group, B represents CO or SO2, X represents a halogen atom, and HX represents an acid.

The above compounds are described on pages 32 and 34 of ``R Surfactant Handbook'' (Kogaku Tosho Co., Ltd., published in May 1978).

The compound having a fluorine atom or a silicon atom may be a polymerizable monomer having a fluorine atom or a silicon atom,
For example, CH2-CHCOOCH2CF3 CHz=CHCOOCHz (CF2) 2H・CH2
-CHfl;OOCH2((:F2) 4HGHz= to HCOO(:L (CH2) 2 (CF2) 8HC
H2=C (C)H3)COOCH2CF3CI(2~
G ((:H3)COO to H2 (CF2) 2HCH
2-C (CH3) COOCH2 (CF2) 4HCH
2-C (CH3)COOCH2 ((:H2) 2
(CFz)aH can be mentioned.

The protective layer is formed by dissolving the above compound in an organic solvent composition containing an organic solvent capable of dissolving the resin substrate and an organic solvent capable of dissolving the dye, and applying an ultraviolet curable resin with a viscosity of 10 eps (25°C) or less. Prepare a liquid and apply it to the entire surface of the reflective layer and the disk-shaped resin substrate while removing the exposed portion of the dye recording layer existing in the area other than the area where the annular reflective layer is provided, and then apply the coating. This is done by irradiating the layer with ultraviolet light.

Examples of the organic solvent that can dissolve the resin substrate and the organic solvent that can dissolve the dye include esters such as ethyl acetate, butyl acetate, and cellosolve acetate, ketones such as methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone, dichloromethane, 1.2- Logenated hydrocarbons such as dichloroethane and chloroform, ethers such as tetrahydrofuran, ethyl ether and dioxane, alcohols such as ethanol, n-propanol, isopropanol and n-butanol, amides such as dimethylformamide, 2.2 .3.3, fluorine-based solvents such as tetrafluoropropanil, etc. can be mentioned. Organic solvents that can dissolve resin substrates are generally the above-mentioned solvents excluding aliphatic hydrocarbon solvents and lower alcohols. Organic solvents that can dissolve dyes vary depending on the dye; for example, in the case of cyanine dyes, they are generally halogenated carbonized solvents. Hydrogen, fluorine solvents, etc.

Ultraviolet rays can be irradiated using, for example, a high-pressure mercury lamp (80 to 200 W).
/ cm), the irradiation distance l1110~50c
This can be done by irradiating the coated layer with ultraviolet rays at m for 0.1 to 100 seconds.

The thickness of the protective layer is less than 5 μm, preferably in the range of 0.5 to 3 μm.

less than, Examples and comparative examples of the present invention are described. Ru.

Tatashi, Each of these aspects shall not limit the invention. It's not.

[Example 1 ] Pigments with the following structure: 1.

g and the following dyes in the above dyes RG- 023, manufactured by Nippon Kayaku ■): 0.

7g, 2゜ 2.

3.

3-tetrafluorob Dissolve in Robatool and apply dye recording layer coating solution (concentration 1.7@% by weight) was prepared.

A disc-shaped polycarbonate substrate equipped with a tracking guide (outer diameter: 120 mm, inner diameter.

15mm, thickness: 1.2mm, track pitch = 1.6
The above coating liquid was applied onto the recording layer (μm, group depth: 900λ) by a spin code method at a rotational speed of 1000 rpm, and then dried to form a recording layer with a thickness of 1300×.

Au is deposited on the dye recording layer to a film thickness of 1300λ.
A reflective layer was formed on the substrate with an inner diameter ranging from 44 mm to 116 mm. At that time, as shown in the attached figure 2, the reflective layer is formed in the inner non-recording area @ 33 provided at the periphery of the hole in figure 3.
Vapor deposition was performed using a mask in order to provide an area other than the inner non-recording area 34 provided inside the outer peripheral edge.

After coating the coating liquid for forming a protective layer (A in Table 1) on the reflective layer using a spin code method, a high-pressure mercury lamp (100%
w/cm) at an irradiation distance of 11,120 cm for 30 seconds to form a protective layer with a thickness of 2 μm. At this time, the dye existing in the inner non-recording area 33 and the inner non-recording area 34 provided inside the outer periphery is removed, and the protective layer is replaced with a reflective layer as shown in FIG. It was provided on the entire surface of the inner non-recording area and the outer non-recording area.

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

[Comparative Example 1] An information recording medium was produced in the same manner as in Example 1 except that B in Table 1 was used instead of the coating liquid for forming a protective layer in Table 1.

[Comparative Example 2] An information recording medium was produced in the same manner as in Example 1 except that C in Table 1 was used instead of the coating liquid for forming a protective layer in Example 1.

[Comparative Example 3] An information recording medium was produced in the same manner as in Example 1 except that D in Table 1 was used instead of the coating liquid for forming a protective layer in Example 1.

[Example 2] An information recording medium was manufactured in the same manner as in Example 1 except that E in Table 1 was used instead of A in Table 1 as the coating liquid for forming a protective layer.

[Comparative Example 4] An information recording medium was produced in the same manner as in Example 1 except that F in Table 1 was used instead of A in Table 1 as the protective layer forming coating liquid.

[Comparative Example 5] An information recording medium was produced in the same manner as in Example 1 except that G in Table 1 was used instead of A in Table 1 as the coating liquid for forming a protective layer.

[Comparative Example 6] An information recording medium was produced in the same manner as in Example 1, except that H in Table 1 was used instead of A in Table 1 as the coating liquid for forming a protective layer.

[Comparative Example 7] An information recording medium was produced in the same manner as in Example 1 except that the protective layer forming coating liquid shown in Table 1 was replaced with A in Table 1.

Table 1■ TMMTA 55 55 55 55 -
− −− −− 55 55 special T8 40
40 40 40 40 -- -- 40 40DP
HA 5 5 5-5 5 5
5 5TMPTA ---------------------
55555516-HD ----------4
02-EHA ------------403
00--Fluoride 0.50.5-0.50.50.50
．． 50.5-Initiator 222222222 Toluene EtAc elAc AA The abbreviations in Table 1 are as follows.

TMMTA: Tetramethylolmethane tetraacrylate Special TA: Special triacrylate compound (the above structural formula:
TA-1, Aronix M-315, manufactured by Toagosei Chemical Industry Co., Ltd.) DPHA Nidipentaerythritol hexaacrylate TMPTA: l-limethylolbroban triacrylate 1.6-HD: 1,6-hexanediol diacrylate 2-EHA ・2-Ethylhexyl acrylate fluoride difluorine surfactant (F-177, manufactured by Dai-Nippon Ink Chemical Industry ■) Initiator: (Irgacure 1173, Ciba Gaiki ■
EtAc: Ethyl acetate Ce1Ac: Cellosolve acetate DAA: Diacetone alcohol [Evaluation of information recording media (■) Adhesion Mylar tape (made by Scotch ■) was completely adhered to the surface of the protective layer of the information recording medium obtained above. The protective layer was peeled off by pulling at an angle of 90 degrees to the surface, and the protective layer that did not peel off was designated as AA, and the one that did peel off was designated as CC.

2) Scratch resistance The surface of the protective layer of the information recording medium obtained above was
Using a pencil H specified in S 6006, the pencil lead was pressed against the surface at an angle of 45 degrees, and when pushed forward, those that did not scratch the surface were rated AA, and those that were scratched were rated CC.

3) Storage stability The information recording medium obtained above was recorded using an optical disk evaluation machine (DDUlooO, manufactured by Pulstech Industries Ltd.) at a racer power (recording power) of 6 mW.
, EFM signals were recorded at a linear velocity of 1.2 m/sec. After storing the recorded information on the information recording medium for 1000 hours (8
0° C., 80% RH), and jitter was measured.

The jitter is measured using the R obtained by reproduction using the above-mentioned evaluation machine.
The F playback signal is processed using a pulse jitter counter (TR5835).
This was done by inputting the information into the software (manufactured by Atohan Chist). The measurement conditions were reproduction power and o65. The measurement conditions were: playback power m: 0.5mW, linear velocity: 1.2m/sec, playback chair output AC cup link, window width: lower side 575n.
s, upper 812.5ns, polarity, +, slice level:
It was carried out at 0 ■.

A jitter of less than 30 ns was rated as AA, and a jitter of 30 ns or more was rated as CC.

4) Adhesion 1 (After storage at high temperature and high humidity) The adhesion test in 1) was conducted on the protective layer of the information recording medium after storage for 1000 hours (80°C, 80% RH) as described above, and the protective layer did not peel off. The one that was peeled off was designated as AA, and the one that was peeled off was designated as CC.

5) Appearance The appearance of the protective layer of the information recording medium obtained above was visually observed. Those with uniform layer thickness and no layer thickness unevenness were designated as AA, and those with uniform layer thickness were designated as CC.

The results obtained are shown in Table 2.

Table 2 Actual Ratio Actual Ratio Ratio Grade (cps) 7 (μm) As shown in Table 2, the polymerizable-polymer bond according to the present invention The information recording media of Examples 1 and 2, which are composed of a monomer having 3 or 4 monomers and a fluorine-containing surfactant having 5 or more monomers, have excellent adhesion and scratch resistance, and are free from jitter and adhesion after storage. It can be seen that the properties are good and the durability is significantly superior.The appearance is also good.

On the other hand, Comparative Example 1, which has a thick layer, has poor adhesion and appearance; Comparative Example 2, which does not contain a surfactant; Comparative Example 3, which does not contain a 1,000-monomer with 5 or more functional monomers; Comparative Example 4, which contains a 2-functional monomer; Comparative Examples 5 and 6 containing monofunctional monomers had poor storage stability)
ing. Moreover, in Comparative Example 7, in which the solvent was reduced in Comparative Example 2 and the coating was applied in a relatively high viscosity state, the appearance was even worse. Furthermore, all comparative examples have problems with adhesion after storage.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing the structure of the information recording medium of the present invention. FIGS. 2 and 3 are schematic partial cross-sectional views for explaining the method for manufacturing an information recording medium of the present invention. 10.20.30: Hole 11.21.31: Disc-shaped resin substrate 12.22.32: Dye recording layer 23/partially uncoated area 13.33: Inner non-recording area 14.34: Outer periphery Side non-recording area 15.35: Reflective layer 16 Protective layer Patent applicant Fuji Photo Film Co., Ltd. Agent Patent attorney Yasushi Yanagawa

Claims (1)

[Scope of Claims] 1. A dye recording layer provided in an annular shape on a disc-shaped resin substrate and capable of recording information using a laser, and on the annular recording layer, an inner peripheral edge and an outer peripheral edge of each of the annular recording layers. an annular reflective layer made of metal laminated so that side edges coincide with each other, and an inner circumferential side edge and an outer circumferential side edge extending beyond the inner circumferential side edge and outer circumferential side edge of the reflective layer, respectively; , a protective layer provided on the reflective layer so as to be in contact with the surface of the discoidal substrate, and the protective layer comprises a compound having at least 5 polymerizable double bonds and 3 or 4 polymerizable double bonds. An information recording medium characterized in that the protective layer is a hardened layer formed by a polymerization reaction with a compound containing a fluorine atom or a silicon atom, and the hardened layer contains a compound having a fluorine atom or a silicon atom, and the thickness of the protective layer is less than 5 μm. . 2. A step of coating and forming a dye recording layer capable of recording information by laser on a disc-shaped resin substrate, a step of forming an annular reflective layer on the recording layer, having at least 5 polymerizable double bonds. compound, a compound having 3 or 4 polymerizable double bonds, and a compound having a fluorine atom or a silicon atom in an organic solvent composition containing at least an organic solvent capable of dissolving a resin substrate and an organic solvent capable of dissolving a dye. A dissolved ultraviolet curable resin coating liquid having a viscosity of 10 cps (25°C) or less is applied to the reflective layer while removing the exposed portion of the dye recording layer existing in the area other than the area where the annular reflective layer is provided. A method for manufacturing an information recording medium, comprising the step of coating the entire surface of the disc-shaped resin substrate and then irradiating the coated layer with ultraviolet rays to form a protective layer.