JP2000105945A - Optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical information recording medium having degradability when it is allowed to stand in the natural world by using a degradable polymer having at least one of photodegradability and biodegradability as part or all of the material of at least the substrate of a medium with a light interference layer containing a dye phase on the substrate. SOLUTION: The degradable polymer is preferably an ethylene copolymer of formula I, wherein each of (x) and (y) is the number of repeating units on the condition of x+y=100, (X) is 50-99.9, (y) is 0.1-50, X is nitrile or a group of formula II, III or IV and each of R1-R3 is H or 1-3C alkyl. The ethylene copolymer is obtained by copolymerizing ethylene and 2-nitrile-3-vinyloxirane, 2-acetyl-3-vinyloxirane, 2-acetoxy-3-vinyloxirane, 2-acetamide-3-vinyloxirane or the like in the presence of a radical polymerization initiator. A used medium is discarded while suppressing environmental pollution and treatment cost is also reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording medium using a material which is easily decomposed in a natural environment so as to be easily disposed after use.

[0002]

2. Description of the Related Art As a means for recording and reproducing data such as images such as characters and figures, video or audio, a wavelength 77 is used.
An optical disc having a recording layer containing a pentamethine cyanine dye, for example, is known as a CD-R as a recording material capable of recording and reproducing corresponding to a laser beam of 0 to 830 nm. An optical disk DVD-R (Digital / Digital) capable of high-density recording and reproduction with red laser light of 620 to 690 nm.
Video disc-recordable or digital versatile disc-recordable) and the like have come to be used as media for the future era. Such an optical information recording medium such as a CD-R or a DVD-R is provided with a recording layer containing a dye on a substrate, and further provided with a reflective layer and further a protective layer as necessary. However, a polycarbonate resin is generally used as the substrate. This is because the polycarbonate resin has high mechanical strength (impact resistance), is hardly broken when handling an optical disk, and has excellent transparency when recording and reproducing with a laser.

[0003]

However, when a used optical disc is discarded in a natural environment when discarded, it is difficult to disassemble the disc by simply leaving it alone.
In particular, a substrate occupying a large part of the entire structure has a problem that when it is made of a polycarbonate resin, it is poor in decomposability by natural light and decomposability by microorganisms (biodegradability), and remains as dust for a long time. In order to avoid this problem, if an attempt is made to incinerate the gas, harmful substances are contained in the gas generated during combustion, and if the gas is discharged into the atmosphere as it is, it will cause air pollution, which is problematic in terms of environmental protection. In addition, it is conceivable to recycle the used optical disk substrate to make effective use of resources. However, when the resin of the material is recycled from the used substrate, especially in the case of polycarbonate resin, the substrate made of the recycled resin is used. However, the excellent transparency inherently lost is remarkably lost, and there is a problem in transparency as a substrate such as a CD-R for recording and reproducing using a laser.

[0004] A first object of the present invention is to provide an optical information recording medium having decomposability even when left in the natural world. A second object of the present invention is to provide an optical information recording medium that can dispose of used products with less pollution. A third object of the present invention is to provide an optical information recording medium that can reduce the cost of disposal of used products. A fourth object of the present invention is to provide an optical information recording medium to which a conventional manufacturing method can be applied without major changes.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that a material composed of a photodegradable or biodegradable polymer can be used as a base material or other optical information recording medium. The present inventors have found that the used optical information recording medium can be decomposed by simply leaving the used optical information recording medium in the natural world, and the residue can be reduced, and the present invention has been accomplished. Therefore, the present invention
(1) A polymer in which at least a part or all of the material of the optical information recording medium having an optical interference layer including a dye layer on a substrate has at least one of photodegradability and biodegradability. The present invention provides an optical information recording medium constituted by using a degradable polymer. Further, the present invention provides (2), wherein the degradable polymer is an ethylene copolymer represented by the following general formula [1].
Optical information recording medium,

Wherein x and y represent the number of each repeating unit when x + y = 100, and x is 50 to 9
9.9, y is a value of 0.1 to 50, and X is a nitrile group, any one of the following general formulas [Formula 2] to [Formula 4].

(Where R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms),

(Wherein R ₂ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms),

(Wherein R ₃ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms)], (3), and the decomposable polymer is substantially a repeating unit represented by the following [Chemical Formula 5]. Content 5
The optical information recording of the above (1), which is an ethylene copolymer comprising 0 to 99.9 mol% and a content of the repeating unit represented by the following general formula [Formula 6] of 0.1 to 50 mol%. Medium,

Embedded image

Wherein the bonds represented by (a) and (b) are the same as (a)-(a), (b)-(b) and (a)-
X is not bonded by the combination of (b), and X represents a nitrile group or any of the following general formulas [Formula 2] to [Formula 4].

(Where R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms),

(Wherein R ₂ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms),

(Wherein R ₃ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms)], (4), and the decomposable polymer is substantially a repeating unit represented by the following [Chemical Formula 7]. Content 5
0 to 99.9 mol%, the content of the repeating unit represented by the following [Chemical Formula 8] and the following Formula [Chemical Formula 9] is 0.1 to 40 mol%, and the following [Chemical Formula 8] and the following General Formula [ The optical information recording medium according to the above (1), which is an ethylene copolymer having a total amount of 0.2 to 50 mol%

Embedded image

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(Where Y and Z are the same or different substituents, and each represents an alkyl group having 1 to 7 carbon atoms). (5) The degradable polymer is a biodegradable vinyl An object of the present invention is to provide the optical information recording medium of the above (1), which is an alcohol-based polymer.

In the present invention, the optical information recording medium is C
Not only optical disks such as DR and DVD-R, but also write-once tape-type optical information recording media having a recording layer of an organic dye on a base tape, such as a magnetic tape that can be stored in a cartridge, are included. Further, the light interference layer is a recording layer including a single layer or a plurality of dye layers capable of forming pits by laser irradiation, which includes a dye layer formed of an organic dye material and a layer formed of another organic material or an inorganic material, In addition to this recording layer, the refractive index and the film thickness are adjusted for the purpose of adjusting the optical physical properties of the optical information recording medium. And the like, and these are generic names.

[0007] In the present invention, "at least the base among the constituent members of the optical information recording medium is ... using a decomposable polymer" means that the material of each layer of other constituents in addition to the base is degradable. Indicates that a polymer may be used,
The more layers of the constituents are made of degradable polymer, the less residues that will be trash for a long time when left in nature. Further, in the present invention, "a base material uses a degradable polymer in which a part or the whole of the material is a polymer having at least one of photodegradability and biodegradability" means that a "substrate" is a substrate for a disk. However, it may be a tape or another form, and "a part or all of the material uses a degradable polymer."
For example, for a substrate, the case where the whole of the material is a degradable polymer and the substrate is made of the polymer, and the case where a part of the material is the degradable polymer and the molding of the degradable polymer and the molding of another material In some cases, the substrate may be a composite made of a body, or may be a substrate molded from a mixture of a degradable polymer and another material. The same applies to other components.

The "degradable polymer" has at least one of photodegradability and biodegradability, that is, has photodegradability and / or biodegradability, and has photodegradability and biodegradability. Examples of the polymer include an ethylene copolymer represented by the above general formula [Chemical Formula 1] and the above [Chemical Formula 5]
And an ethylene copolymer comprising a predetermined repeating unit of the above general formula [Chemical formula 6], an ethylene copolymer comprising the above [Chemical formula 7], [Chemical formula 8] and the predetermined repeating unit of the above general formula [Chemical formula 9]. Can be mentioned. The ethylene copolymer represented by the general formula [Chemical formula 1] has any one of the above-mentioned general formulas [Chemical formulas 2] to [Chemical formula 4] represented by X and a nitrile group. Chemical formulas _{2 to} 4 each represent a hydrogen atom represented by R ₁ , R ₂ , or R ₃ or a carbon atom having 1 to 3 carbon atoms.
Having an alkyl group of the general formula [Chemical Formula 1]
In order to obtain an ethylene copolymer represented by the following formula, it is obtained by copolymerizing ethylene and at least one compound represented by the following general formula [Formula 10] in the presence of a radical polymerization initiator.

Embedded image (However, X represents the same as that of the general formula [Formula 1].)

Specific examples of the compound represented by the general formula [Chemical Formula 10] include 2-nitrile-3-vinyloxirane, 2-acetoxy-3-vinyloxirane, 2-formyloxy-3-vinyloxirane, -Propionyloxy-3-vinyloxirane, 2-formamide-
3-vinyloxirane, 2-acetamido-3-vinyloxirane, 2-propionamido-3-vinyloxirane, 2-acetyl-3-vinyloxirane, 2-formyl-3-vinyloxirane, 2-propionoyl-3
-Vinyl oxirane and the like. During the copolymerization, at least one other ethylenically unsaturated monomer may be copolymerized in the copolymer up to 10 mol%. Examples of the ethylenically unsaturated monomer include olefins having 3 to 10 carbon atoms, vinyl esters of lower alkane carboxylic acids, ethylenically unsaturated carboxylic acids such as (meth) acrylic acid, maleic acid, and fumaric acid, and the like. Anhydrides, lower alcohol esters of (meth) acrylic acid, and ethylenically unsaturated carboxylic amides such as glycidyl (meth) acrylate and (meth) acrylamide. The copolymerization reaction uses, for example, a commonly used radical polymerization initiator such as peroxide, in the presence or absence of a solvent such as benzene, and optionally uses a chain transfer agent, under pressure,
The reaction can be carried out in a tank type or tube type reactor at normal temperature to heating.

[0010] When the ethylene copolymer thus obtained is heated in the presence of oxygen, a carbonyl group is formed in the polymer molecule very quickly, resulting in a polymer having functions such as photodegradability. Various functional groups can be introduced into the polymer using a reagent that reacts with the carbonyl group of the polymer and the hydrogen at the α-position of the carbonyl group. In the above general formula [Chemical formula 1], x is from 50 to 99.
9, y is 0.1 to 50, but y is preferably 0.3
The polymer represented by the general formula [Chemical Formula 1] preferably has an intrinsic viscosity in decalin at 135 ° C. of 0.04 to 1.2, and when the intrinsic viscosity exceeds 1.2, the moldability decreases. Those having a low intrinsic viscosity can be used as constituents of components other than the substrate, such as protective layers, and those having a high intrinsic viscosity and moldability can be used as substrates such as substrates and tapes.

In the ethylene copolymer comprising the above-mentioned repeating units represented by the above-mentioned formulas (1) and (2), the substituent X and the individual substituents represented by the X are represented by the above-mentioned formula (1). (Substituents R ₁ , R ₂ , R
₃ also represent the same thing), to obtain the ethylene copolymer, ethylene and causes at least the general formula of the compound represented by [Formula 10] are copolymerized in the presence of a radical polymerization initiator. The polymerization mechanism of the copolymerization is represented by the following reaction formula:
1].

Embedded image Further, a growing polymer radical having an ethylene radical at the terminal is bonded to one carbon having a carbon-carbon double bond of the polymer represented by (I), and the radical is transferred to the other carbon atom. The radical attacks the ethylene or the monomer represented by the above formula, and the branched chain grows. From this, in the repeating unit represented by the above general formula [Formula 6], as shown in parentheses of the general formula, (a)-(a), (b)-(b) and (a)-
There is no combination in the combination of (b). The specific compound represented by the general formula [Chemical Formula 10], the type and amount of the ethylenically unsaturated monomer that can be copolymerized, and other reaction conditions are as follows. It is almost the same as that obtained from the compound of the above general formula [Chemical formula 10], and the obtained copolymer has a content of the repeating unit represented by the above [Chemical formula 5] of 50 to 99.9 mol%. The content of the repeating unit represented by the general formula [Formula 6] is 0.1.
1 to 50 mol%, preferably 0.3 to 20 mol%, and the solid phase viscosity of the copolymer in decalin at 135 ° C. is preferably 0.04 to 1.2. It can be said that the properties are almost the same as those of the compound of the above-mentioned general formula [Formula 1]. The compound of the above general formula [Chemical formula 1]
The ethylene copolymer comprising a predetermined repeating unit of the above-mentioned [Chemical formula 5] and the above-mentioned general formula [Chemical formula 6] can be said to be a compound in which a branched chain is further bonded to the compound. The formation ratios of these compounds are different. In general, for example, when the raw material monomer composition is the same, it can be said that the higher the temperature and the pressure, the easier the latter is formed.

In order to obtain an ethylene copolymer comprising the above-mentioned [Chemical formula 7], [Chemical formula 8] and the above-mentioned formula (Formula 9), ethylene and at least one kind of the following formula [Chemical formula 12] Is copolymerized in the presence of a radical polymerization initiator.

Embedded image (However, Y and Z are the same as those of the above-mentioned general formula [Chemical formula 9].) The polymerization mechanism is shown by the following reaction formula [Chemical formula 13].

Embedded image Specific examples of the compound represented by the general formula [Chemical Formula 12] include, for example, 2,2-di- (n-heptyl) -4-methylene-1,3-dioxolane. The type and amount of the ethylenically unsaturated monomer that can be copolymerized and other reaction conditions are substantially the same as those in the case where the compound of the above general formula [Chemical Formula 1] is obtained from ethylene and at least the compound of the above general formula [Chemical Formula 10]. Similarly, the obtained copolymer has a content of the repeating unit represented by the above [Chemical formula 7] of 50 to 99.
8 mol%, the content of the repeating unit represented by the above [Chemical Formula 8] and the above general formula [Chemical Formula 9] is respectively 0.1 to 40 mol%, preferably 0.3 to 20 mol%, and The total amount of the repeating units represented by the general formula [Chemical formula 9] is 0.2 to 50 mol%, and the solid phase viscosity of the copolymer in decalin at 135 ° C. is 0.1%.
04-1.2 is preferred, and more preferably 0.05-
1.0, and it can be said that the properties of the copolymer also have almost the same properties as those of the compound of the above-mentioned general formula [Formula 1].

The above-mentioned ethylene copolymers can be used alone or in combination of two or more. However, as long as the material of the substrate does not impair the transparency and the mechanical strength, and as a constituent component of other constituents, its function is Other materials can be used in combination as long as is not impaired. For example, other olefins (co)
Thermoplastic resin such as polymer, polyacrylonitrile, polyamide, polycarbonate, ABS resin, polystyrene, polyphenylene oxide, polyvinyl alcohol resin, vinyl chloride resin, vinylidene chloride resin, polyester resin, petroleum resin, coumaroindene resin and phenol resin , Thermosetting resins such as melamine resins, ethylene-propylene copolymer rubbers (EPR, EPDM, etc.),
Examples include at least one kind of synthetic rubber such as SBR, NBR, butadiene rubber, IIR, chloroprene rubber, isoprene rubber, styrene-butadiene-styrene block copolymer, and natural rubber. Further, various additives such as an ultraviolet ray inhibitor, an antistatic agent, an antioxidant, a plasticizer, an air bubble inhibitor, a crosslinking agent, and a dispersant may be used in combination.

In the present invention, "biodegradable polymer"
Examples thereof include vinyl alcohol-based polymers. For example, the number average degree of polymerization (Pn) is 50 or less, and the ratio Pw between the weight average degree of polymerization (Pw) and the number average degree of polymerization (Pn)
A vinyl alcohol polymer having / Pn of 1.3 or less is preferred. In order to obtain this special vinyl alcohol polymer, for example, the number average degree of polymerization (Pn) is 50 or less,
Ratio P between weight average degree of polymerization (Pw) and number average degree of polymerization (Pn)
It is obtained by reacting a polyarylvinylether-based polymer having w / Pn of 1.3 or less with sodium in liquid ammonia and saponifying it. The above-mentioned polyaryl vinyl ether-based polymer is obtained by living cationic polymerization of a monomer such as benzyl vinyl ether. For example, polymerization is carried out in an atmosphere of nitrogen, under the condition of complete dehydration, using an organoaluminum reagent as an initiator and setting the initiator concentration at 0.5 (mol / monomer 1 L) or more. As the vinyl alcohol-based polymer, in addition to the structural units of vinyl alcohol, a vinyl ether monomer, a monomer capable of cationic copolymerization, for example, styrene and its derivatives, may have a structural unit composed of isobutene and the like. Good. About such a vinyl alcohol polymer,
As long as the material of the base does not impair the transparency and mechanical strength, and as a component of the other components, as long as the function is not impaired, at least one of the above-described ethylene copolymers and other Resin and additives can be used in combination. In addition, in order to improve the strength of the molded article made of each of the above ethylene copolymers and vinyl alcohol-based polymer materials, using a crosslinking agent, or using a chemical or physical means such as irradiation with radiation. Is also good.

As a method of estimating an isotropic light scattering loss value from the molecular structure of a polymer, isothermal compression and refractive index values are estimated from molecular volume and molecular refraction, and the isotropic scattering loss is estimated from these values. Values are predicted (N. Tanio an
d Y. Koike, Jpn. J. Appl. Phys
s. , 36, 743 (1997). According to the scattering loss values predicted from polymethyl methacrylate (PMMA) and polystyrene (PS), it is necessary to select a polymer having a small isothermal compression ratio and a low refractive index in order to obtain a polymer having a lower scattering loss. Specifically, it has been found that the light scattering loss value of polymethyl methacrylate (PMMA) and polystyrene (PS) is about twice as good as that of the latter. This report indicates that a polymer having no repeating unit having an aromatic ring has a smaller light scattering loss value and thus a higher transparency than a polymer having a repeating unit having an aromatic ring. From this point, from the viewpoint of the transparency of the substrate, it can be said that it is preferable to use a polymer having no repeating unit having an aromatic ring as the degradable polymer used in the present invention, but a polymer having a repeating unit having an aromatic ring is preferable. However, those having excellent transparency and mechanical strength can be used, and when used as a component of a structure other than the substrate, the polymer does not necessarily need to be a polymer having excellent transparency, and a polymer having an aromatic ring having excellent transparency may not be used. But yes.
Examples of the polymer having a repeating unit having an aromatic ring include an unsubstituted or substituted phenyl group as the substituent X (the substituent may be one or two (same or different)
A lower alkyl group, a methoxy group, a nitrile group, an amino group, a nitro group, and a halogen atom. ), .Alpha.-naphthyl group, .beta.-naphthyl group and the like.
No. 821, a polymer having a substituent described in the general formula (I), an unsubstituted or substituted phenyl group which may be the same or different as the substituents Y and Z (a lower alkyl group as a substituent, Examples thereof include a halogen atom, a cyano group, and a methoxy group.) Or a polymer having a substituent of a 2-naphthyl group.

In the present invention, the dyes used in the dye layer include, for example, cyanines such as metal-containing indoanilines, indolenines, phthalocyanines, naphthalocyanines, phenalenes, naphthoquinones, anthraquinones, pyryliums and azo dyes. , Azurenium-based, triarylmethane-based, polymethine-based, and squarylium-based dyes can be used alone or in combination. In order to manufacture the optical information recording medium of the present invention, a dye solution in which a dye is dissolved is prepared and applied to a light-transmitting substrate made of the above-mentioned various materials. For these dye solutions, fluorinated solvents such as chloroform, dichloroethane and fluorinated alcohol, methyl ethyl ketone, dimethylformamide, methanol, toluene, cyclohexanone, acetylacetone, diacetone alcohol, cellosolves such as methylcellosolve, dioxane and the like can be used. . A track groove or a pit may be formed on the substrate, or a substrate having a signal necessary for an address signal may be provided. In addition, it is preferable to use a spin coating method to apply the above-mentioned dye solution to the substrate. In this case, a conventionally used thickness of the coating layer after drying can be applied. Further, the light interference layer in the invention may contain other compounds such as the above-mentioned metal complex and other singlet oxygen quencher, a light absorber, a radical scavenger (scavenger).

A reflective layer may be provided in addition to the above-mentioned light interference layer, and a protective layer may be provided on the reflective layer, and a protective layer may be provided on the substrate surface (on the side where laser light is incident).
As the reflection layer, a high reflectance of a metal film such as Au, Al, Ag, Cu, Pt, each of these other alloys, and an alloy to which a trace component other than these is added, formed by vapor deposition, sputtering, etc. A material film is mentioned, and as a protective layer, a solution of a radiation-curable resin such as an ultraviolet-curable resin is applied by a spin coating method or the like for the purpose of protecting the optical information recording medium and improving weather resistance, and radiation-cured. An application layer is mentioned. At this time, the above-mentioned polymer according to the present invention may be used alone or in combination as it is or modified.

In this way, an optical disk is provided in which the light interference layer including the dye layer and the reflection layer are provided on the substrate, and further the protection layer and the like are provided. An optical disk having another similar configuration or another configuration having at least the light interference layer may be bonded, or the substrate itself may be opposed and bonded. The material for this lamination,
As a method, ultraviolet curable resin, cationic curable resin,
A double-sided pressure-sensitive adhesive sheet, a hot melt method, a spin coating method, a dispensing method (extrusion method), a screen printing method, a roll coating method and the like are used. Also in this case, the above-mentioned polymer according to the present invention may be used as it is, or may be used alone after being modified, or may be used in combination.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described with reference to the following examples. Examples of the degradable polymer include the above-mentioned three types of ethylene copolymers having photodegradability and biodegradability, and biodegradable vinyl alcohol-based polymers. When a substrate is molded using a polymer and an optical disk is produced using the substrate, these polymers do not have a repeating unit having an aromatic ring as described above, and therefore have good transparency and exhibit strength as an intrinsic viscosity. A substrate with a high molecular weight or a substrate whose other structure can be increased by using a similar polymer together is obtained, and when the used optical disk using the substrate is discarded, the optical disk can be used in nature. It can be decomposed just by leaving it unattended, so that it does not remain.

[0020]

EXAMPLES Examples 1 to 5 As a photodegradable and biodegradable ethylene copolymer as a degradable polymer, a polymer belonging to the above general formula [1] is used as a material for a substrate. That is, as shown in Table 1, each of the ethylene copolymers used in Examples 1 to 5 was obtained by the following production method and purification method according to the composition of the raw material monomers and other polymerization conditions, and the yield and properties were shown for each. It is. In the table, [η] is the intrinsic viscosity in decalin at 135 ° C. measured by a predetermined method, and “comonomer” indicates a monomer belonging to the above general formula [Formula 3]. For each ethylene copolymer, a metal autoclave type reactor equipped with a stirrer having an internal volume of 320 ml was sufficiently replaced with nitrogen and ethylene, and then a predetermined amount of ethylene was charged. Tertiary butyl peroxide (DTBP) was injected with 39 g of a 2: 1 mixture of benzene and n-hexane, and polymerization was carried out under predetermined conditions for 4.5 hours. When the average molecular weight of the produced polymer was relatively high, the polymer was dissolved in heated toluene, and then poured into a large amount of methanol to precipitate the polymer, followed by filtration and washing, followed by vacuum drying and purification. When the produced polymer had a relatively low average molecular weight, the polymer was purified by removing the unreacted monomer, benzene, and n-hexane by heating and evaporating under reduced pressure. The intrinsic viscosity [η] is measured by dissolving the polymer in heated decalin at a concentration of 40 mg / 20 ml, measuring the relative viscosity (η _r ) at 135 ° C. with an Ubelod viscometer, and obtaining the following formula. [Η] = (lnη _r ) / C (where C is the concentration of the polymer solution, g / 100 ml).
It was molded into a μm sheet or dissolved in heated carbon tetrachloride, this solution was dropped on a rock salt plate, and then carbon tetrachloride was volatilized to form a polymer thin film on the rock salt plate, and infrared spectroscopy was performed. . Further, a solution of the purified polymer in orthodichlorobenzene was used as a solution of ¹³ C--N at 80 DEG C.
Analysis by MR spectrum was performed to confirm each ethylene copolymer.

The surface has a width of 0.32 μm, a depth of 100 nm,
A transparent substrate made of each ethylene copolymer for Examples 1 to 5 having a thickness of 0.6 mm and an outer diameter (diameter) of 120 mm in which spiral grooves having a pitch of 0.74 μm are formed is formed by injection molding. I do. Next, a trimethine-based cyanine dye NK-2084 (manufactured by Japan Photographic Dye Laboratories)
And a metal complex as a light stabilizer in a weight ratio of 95: 5, and this mixture is mixed with a fluorinated alcohol such as 2,2,2.
It was dissolved in 3,3-tetrafluoro-1-propanol (manufactured by Tokyo Chemical Industry Co., Ltd .; hereinafter abbreviated as TFP) so as to have a concentration of 3% by weight, and the solution was applied to the surface of the substrate by a spin coating method, and the film thickness was 60 nm. To form a light interference layer comprising a photosensitive dye film.

On the light interference layer, the substrate is shifted from 44 mmφ by 1 mm.
An Au film having a thickness of 80 nm is formed on the entire surface of the region of 17 mmφ by a sputtering method to form a reflection layer. Also,
A UV-curable resin SD-211 (manufactured by Dainippon Ink and Chemicals, Inc.) is spin-coated on the reflective layer, and the coating film is cured by irradiating ultraviolet rays to form a protective film having a thickness of 5 μm. Further, an ultraviolet curable resin SD-318 is formed on the protective film of the substrate and the light interference layer on which the protective film is not formed.
(Dai Nippon Ink Chemical Industry Co., Ltd.) was dropped, and another substrate molded in the same manner as above was placed on it, and the resin was diffused in the gap by a spin coating method. Curing from the beginning, 3 of the substrate from the beginning
Thickness 2 made of resin in the area of 2mmφ to 120mmφ
By forming an adhesive layer having a thickness of 5 μm, the laminated substrates are attached to each other to produce a bonded optical disk.

The optical disk manufactured in this manner is
The substrate can be provided with a jitter, a modulation degree after recording, and other functions as an optical disk, and the substrate has photodegradability and biodegradability due to the characteristics of its material.

Examples 6 to 10 Examples 1 to 5 obtained in the same manner as in Examples 1 to 5 shown in Table 1 except that the polymerization conditions other than the starting monomer composition were changed as shown in Table 2. Each substrate was prepared in the same manner except that an ethylene copolymer (copolymer within a predetermined ratio range of the repeating unit represented by the above [Chemical Formula 5] and the above general formula [Chemical Formula 6]) was used. Then, each optical disk is manufactured using each substrate.
The optical disk manufactured in this way can have jitter, the degree of modulation after recording, and other functions as an optical disk, and the substrate has photodegradability and biodegradability due to the characteristics of its material.

Example 11 An ethylene copolymer composed of a polymer in which the repeating units of the above [Chemical Formula 7], [Chemical Formula 8] and the above general formula [Chemical Formula 9] fall within a predetermined ratio range is used as a material for a substrate. As shown in Table 3, the ethylene copolymer was obtained according to the composition of the raw material monomers and other polymerization conditions, and the yield and properties of the copolymer are also shown. The other polymerization conditions were the same as in Example 1 above.
The same as in the case of Nos. 5 to 5. In the table, [η] is the intrinsic viscosity in decalin at 135 ° C. measured by the above method, and “polymer composition (mol%)” is represented by the above general formula [Chemical Formula 1].
3] shows x, y, and z of the formula (II). An optical disk is manufactured in the same manner as in Examples 1 to 5, except that the above-mentioned materials are used. The optical disk manufactured in this way can have jitter, the degree of modulation after recording, and other functions as an optical disk, and the substrate has photodegradability and biodegradability due to the characteristics of its material.

Example 12 A vinyl alcohol polymer having a weight-average degree of polymerization and a number-average degree of polymerization (Pw / Pn) within a predetermined range is used as a material for a substrate as a decomposable polymer. That is, in the step of polymerizing a solution of benzyl vinyl ether using an n-hexane solution of ethylammonium dichloride and saponifying the polymer with metal sodium in liquid ammonia, Pn = 9, Pn
w / Pn = 1.26, Pn = 18, Pw / Pn =
1.27, Pn = 46, Pw / Pn = 1.12 3
Kinds of vinyl alcohol polymers (all 9
9.9 mol%), and when the strength of each is insufficient, another vinyl alcohol polymer having a high degree of polymerization (for example, vinyl alcohol polymer (Pn
= 528, Pw / Pn = 1.19, saponification degree 99.9 mol%), etc., to prepare a substrate containing each of these. The detailed production method of the above vinyl alcohol-based polymer is as follows. A glass reaction vessel equipped with a three-way stopcock is prepared, replaced with nitrogen, heated in a nitrogen gas atmosphere, and sucked by a vacuum pump to form a glass reaction vessel. The adsorbed water in the container was removed. Next, using a syringe which has been replaced with dry nitrogen, 184 mL of toluene, 30 mL of ethyl acetate, 30 mL of bezyl vinyl ether, and 6 mL of a toluene solution of trifluoroacetic acid (13.5 mL of toluene and 6 mL of trifluoroacetic acid under a dry nitrogen atmosphere in advance).
L was added to the reaction vessel in this order, and the reaction system was cooled using an ice bath. When the temperature in the system reaches 0 ° C, ethyl aluminum chloride n-
A polymerization reaction was started by adding 50 mL of a hexane solution (1 mol / L). After 3 minutes, 50 mL of methanol was injected into the reaction system to stop the polymerization reaction. After the termination of the polymerization reaction, the residue was washed twice with 5% hydrochloric acid to remove the initiator residue,
Next, after neutralizing with a 2% sodium hydroxide solution, the reaction solution was concentrated and dried under reduced pressure to collect PBzVE. Next, the reaction of cleavage of the ether bond of the obtained PBzVE will be described.
After cooling to −78 ° C. in a dry ice-methanol cooling system, 1.2 L of liquid ammonia was introduced. 13.2 g of metallic sodium was charged into a reaction vessel, and the concentration of the above PBzVE 25 g was added to blue liquid ammonia.
% Dimethoxyethane solution was added dropwise. After dropping, 3
The reaction was left for a period of time. After completion of the reaction, 45 g of ammonium acetate was added into the reaction vessel to stop the reaction. next,
After passing ammonia through the reaction vessel to completely evaporate the ammonia, about 200 mL of distilled water was added into the reaction vessel,
After filtration, the solvent was distilled off from the filtrate using a rotary evaporator. After filtering a solution obtained by dissolving the white solid obtained in the above operation in 150 mL of distilled water, the cation exchange resin (DOWEX50WX8, H ⁺
Pass through a mold 1 L at a rate of 1-2 mL / min / cm ² ,
Sodium ions and ammonium ions in the aqueous solution were converted to hydrogen ions. Next, by passing through 1 L of an anion exchange resin (IRA-400, 0H ^- type), acetate ions in the aqueous solution were removed, and hydrogen ions were further neutralized. Next, water was distilled off from the ion-exchanged solution using a rotary evaporator, followed by vacuum drying at 40 ° C. to obtain PVA. ¹ H-NMR (nuclear magnetic resonance) of the PVA
The number-average degree of polymerization (Pn) determined from the measurement value according to the above was 9. GPA at 40 ° C. using THF of polyvinyl acetate obtained by acetylating the PVA by a conventional method as a solvent.
The ratio (Pw / Pn) of the weight-average degree of polymerization in terms of standard polystyrene determined by C measurement to the number-average degree of polymerization was 1.26.

The detailed production method of the above vinyl alcohol polymer is the same as in the case of the above vinyl alcohol polymer, 212 mL of toluene and 30 mL of ethyl acetate.
mL, 30 mL of benzyl vinyl ether, and 3 mL of a toluene solution of trifluoroacetic acid (a part of a mixture obtained by mixing 13.5 mL of toluene and 6 mL of trifluoroacetic acid in advance under a dry nitrogen atmosphere). The reaction was cooled using an ice bath. When the temperature in the system reached 0 ° C., 25 mL (1 mol / L) of an ethyl aluminum dichloride n-hexane solution was added to start a polymerization reaction. After 30 minutes, the polymerization reaction was stopped by injecting 20 mL of methanol into the reaction system. Thereafter, PBzVE was recovered by purifying in the same manner as in the case of the above vinyl alcohol-based polymer. Next, regarding the cleavage reaction of the ether bond of the obtained PBzVE, the reaction vessel was sufficiently purged with nitrogen, cooled to -78 ° C in a dry ice-methanol cooling system, and 1.2 L of liquid ammonia was introduced. Metallic sodium 1 in the reaction vessel
Into 3.2 g of blue liquid ammonia, a 10% dimethoxyethane solution of 25 g of PBzVE described above was added dropwise. After completion of the dropwise addition, the mixture was left for 3 hours to react. Next, PVA was obtained by purifying in the same manner as in the case of the vinyl alcohol-based polymer. The PV
About A, Pn calculated | required similarly to the case of the said vinyl alcohol type polymer was 18, and Pw / Pn was 1.27.

The detailed production method of the above vinyl alcohol polymer is the same as in the case of the above vinyl alcohol polymer.
mL, 30 mL of benzyl vinyl ether, and 6 mL of a toluene solution of trifluoroacetic acid (a part of a mixture obtained by mixing 18.9 mL of toluene and 0.6 mL of trifluoroacetic acid in advance under a dry nitrogen atmosphere) in the order of the reaction vessel. Was added and the reaction was cooled using an ice bath. System temperature is 0 ℃
, 25 mL of ethyl aluminum dichloride n-hexane solution (1 mol / L) was added to initiate the polymerization reaction. After 30 minutes, the polymerization reaction was stopped by injecting 20 mL of methanol into the reaction system. Thereafter, PBzVE was recovered by purifying in the same manner as in the case of the above vinyl alcohol-based polymer. Next, regarding the cleavage reaction of the ether bond of the obtained PBzVE, the reaction vessel was sufficiently purged with nitrogen, cooled to -78 ° C in a dry ice-methanol cooling system, and 1.2 L of liquid ammonia was introduced. Metallic sodium 1 in the reaction vessel
3.2 g was charged, and the above-mentioned dimethoxyethane solution of 25 g of PBzVE having a concentration of 10% was dropped into liquid ammonia having a blue color. After completion of the dropwise addition, the mixture was left for 3 hours to react. Next, PVA was obtained by purifying in the same manner as in the case of the vinyl alcohol-based polymer. For the PVA, the Pn determined was 46 in the same manner as in the case of the vinyl alcohol-based polymer, and Pw /
Pn was 1.12.

The detailed method for producing the above-mentioned vinyl alcohol-based polymer to be used in combination is the same as in the case of the above-mentioned vinyl alcohol-based polymer, and 39.5 mL of toluene, 60 mL of ethyl acetate, 60 mL of benzyl vinyl ether, toluene solution of trifluoroacetic acid 6 mL (97 mL of toluene and 0.6 mL of trifluoroacetic acid in advance under a dry nitrogen atmosphere)
The mixture was added to the reaction vessel in the order of (a part of the mixture obtained by mixing), and the reaction system was cooled using an ice bath. System temperature is 0
When the temperature reached ° C, 6 mL of an ethylaluminum dichloride n-hexane solution (1 mol / L) was added to initiate a polymerization reaction. After 30 minutes, the polymerization reaction was stopped by injecting 20 mL of methanol into the reaction system. Thereafter, PBzVE was recovered by purifying in the same manner as in the case of the above vinyl alcohol-based polymer. Next, the cleavage reaction of the ether bond of the obtained PBzVE will be described.
The mixture was cooled to -78 ° C in a methanol cooling system, and 1.2 L of liquid ammonia was introduced. 13.2 g of metallic sodium was charged into a reaction vessel, and into blue liquid ammonia,
A 25% dimethoxyethane solution of PBzVE with a concentration of 10% was added dropwise. After completion of the dropwise addition, the mixture was left for 3 hours to react. After completion of the reaction, 45 g of ammonium acetate was added into the reaction vessel to stop the reaction. Next, nitrogen was passed during the reaction, and ammonia was completely distilled off.
The reaction mixture was added to the reaction vessel with mL of distilled water, filtered, and the filtrate was evaporated using a rotary evaporator to remove the solvent. The filtrate was concentrated to a white suspension. This was put into 4.5 L of methanol to perform reprecipitation. After air-drying, 2
By performing vacuum drying for a day, PVA was obtained. The Pn of the PVA was determined to be 528 in the same manner as in the case of the vinyl alcohol-based polymer, and the Pw
/ Pn was 1.19.

Examples 1 to 5 except that the above materials were used.
In the same manner as in the above, an optical disk is manufactured. The optical disk manufactured in this manner can have jitter, the degree of modulation after recording, and other functions as an optical disk, and the substrate has biodegradability due to the characteristics of its material. A substrate obtained from a material containing a decomposable polymer has decomposability at least for the decomposable polymer, and can reduce residues that are hardly decomposed. In addition, the above ~
According to the results of conducting a biodegradation activity test using a PVA oxidase (PVA Dehydrogenase) isolated from a PVA-degrading bacterium, the biodegradability of the vinyl alcohol-based polymer alone used in combination was determined by ordinary radical polymerization. Compared to the obtained vinyl alcohol polymer,
It is shown that the biodegradability is about twice as good as that used in combination, about three times as good as above, and about six times better as above.

In each of the above inventions, "the base is composed of a degradable polymer which is a polymer having at least one of photodegradability and biodegradability in part or all of its material, and It has transparency that enables recording and reproduction by laser light, and has strength enough to withstand practical use during handling ”.

[0032]

According to the present invention, it is degradable even when left in the natural world, the disposal of used products can be performed with less occurrence of pollution, and the cost of the disposal can be reduced. It is possible to provide an optical information recording medium that can be manufactured by applying a conventional manufacturing method without major changes.

[Table 1]

[Table 2]

[Table 3]

Continued on the front page (72) Inventor Kazuyuki Shibuya 6-16-20 Ueno, Taito-ku, Tokyo Taiyo Electric Power Co., Inc. (72) Inventor Koichi Kiyooka 6-16-20 Ueno, Taito-ku, Tokyo Taiyo Invitation F-term in Dentsu Co., Ltd. (reference) 4J005 AA05 AA11 BB01 BD05 4J032 AA34 AA42 AB04 AB36 AC03 AC32 AC33 AD46 AE14 AF08 5D029 KA01 KA08 KA12 KC20

Claims (5)

[Claims] 1. An optical information recording medium having a light interference layer including a dye layer on a substrate, wherein at least the substrate has at least one of photodegradability and biodegradability in part or all of the material. An optical information recording medium configured using a degradable polymer that is a polymer. 2. The optical information recording medium according to claim 1, wherein the degradable polymer is an ethylene copolymer represented by the following general formula [1]. Embedded image [However, x and y represent the number of each repeating unit when x + y = 100, x is 50 to 99.9,
y is a value of 0.1 to 50, and X is a nitrile group, and represents any one of the following general formulas [2] to [4]. Embedded image (Where R ₁ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms). (Where R ₂ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms). (However, R ₃ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)] 3. The decomposable polymer is substantially the following:
Content of the repeating unit represented by 50 to 99.9 mol%
The optical information recording medium according to claim 1, wherein the optical information recording medium is an ethylene copolymer having a content of a repeating unit represented by the following general formula [Formula 6] of 0.1 to 50 mol%. Embedded image , [However, the bonds represented by (a) and (b) are not bonded to each other by a combination of (a)-(a), (b)-(b) and (a)-(b). And X represents a nitrile group or any one of the following general formulas [Formula 2] to [Formula 4]. (Wherein, R ₁ represents a hydrogen atom and an alkyl group having 1 to 3 carbon atoms), and (where R ₂ represents a hydrogen atom and an alkyl group having 1 to 3 carbon atoms). (Wherein R ₃ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)] 4. The decomposable polymer is substantially the following:
The content of the repeating unit represented by the formula is 50 to 99.9 mol%, the content of the repeating unit represented by the following [Chemical Formula 8] and the following general formula [Chemical Formula 9] is 0.1 to 40 mol%, and The total amount of [Chemical formula 8] and the following formula [Chemical formula 9] is 0.2 to 5
2. The optical information recording medium according to claim 1, wherein the optical information recording medium is an ethylene copolymer composed of 0 mol%. Embedded image , , (However, Y and Z are the same or different substituents and each represent an alkyl group having 1 to 7 carbon atoms.) 5. The optical information recording medium according to claim 1, wherein the degradable polymer is a biodegradable vinyl alcohol polymer.