JP3507929B2 - Optical recording medium and manufacturing method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium having improved optical characteristics and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, the development of a write-once CD (compact disc) has become active. This is a conventional CD
Unlike a CD, a user can record information and the signal after recording satisfies the standard of the conventional CD, so that a commercial CD
It has the feature that it can be played back by the player. As one of methods for realizing such a medium, Japanese Patent Laid-Open No. 2-4
In Japanese Patent No. 2652, it is proposed that a dye is spin-coated on a substrate to provide a light absorption layer, and a metal reflection layer is provided behind it. Furthermore, Japanese Patent Laid-Open No. 2-13
As described in Japanese Patent No. 2656, by appropriately selecting the complex refractive index and the film thickness of the light absorbing layer, the signal after recording satisfies the CD standard, and is commercialized as a write-once CD. There is.

[0003]

However, Japanese Unexamined Patent Application Publication No.
The write-once type CDs using the dyes disclosed in JP-A-42652 and JP-A-2-132656 are still insufficient in light resistance. In other words, the signal characteristics change when exposed to sunlight for a long time, and the CD
There is a drawback that the standard cannot be satisfied. This is because the dye material used for the light absorption layer, particularly the cyanine dye that has been used conventionally, changes due to light. Therefore, in order to suppress this change, JP-A-63-63
It is known to contain a light stabilizer in the light absorption layer as disclosed in Japanese Patent Publication No. 159090. But,
When the light stabilizer is added in a small amount (20% or less), sufficient light resistance cannot be obtained, and conversely, when added in a large amount (20% or more), the optical and / or heat of the light absorption layer is not increased. However, there has been a problem that various characteristics are changed and various signal qualities are deteriorated.

On the other hand, JP-A-3-62878 discloses a write-once type CD using a phthalocyanine compound which is a highly light-resistant dye. By adding a specific group to the phthalocyanine compound, the complex refractive index of the light-absorbing layer spin-coated with the phthalocyanine compound was adjusted to a value required for the write-once CD to realize a high light resistance write-once CD. Is. However, the write-once type CD disclosed in Japanese Patent Laid-Open No. 3-62878 was inferior in the quality of the reproduced signal as compared with the conventional one using the cyanine dye in the light absorbing layer. That is, there is a problem that the length (pit length) of each signal forming the reproduction signal is likely to deviate from the original theoretical value of the CD signal, and a reproduction error may occur.

Therefore, it is an object of the present invention to provide a high lightfastness optical recording medium using a phthalocyanine compound in the light absorption layer, which does not have the above-mentioned problems related to reproduction signals, and a method for producing the same.

[0006]

As a result of intensive studies, the present inventor has found that, in the above-mentioned conventional optical recording medium, a phthalocyanine compound represented by the following general formula (I):
It was found that the above-mentioned problems can be solved by using a coordination bond with a nitrogen-containing compound selected from an optionally substituted or cyclized amino compound, imino compound and azo compound, and the present invention Has been completed.

That is, according to the present invention, in an optical recording medium in which at least a light absorbing layer is provided on a substrate, the light absorbing layer comprises a metal phthalocyanine compound (1) represented by the following general formula (I): An optical recording medium, which comprises a coordination bond with a nitrogen-containing compound (2) selected from an amino compound, an imino compound and an azo compound, which may be substituted or cyclized, as a main component. Will be provided.

[Chemical 1] (In the formula, M and A ^{1 to} A ⁸ each represent the following: M: at least one metal ion selected from Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Zn ²⁺ and Cd ^2+. A ¹ and A ² , A ³ and A ⁴ , A ⁵ and A ⁶ and A ⁷ and A ⁸ : either one of them is an oxy (or thio) phenyl group represented by the following general formula (II) or the following: General formula (III)
A thiophenyl group represented by and the other is a hydrogen atom. However, at least one of A ^{1 to} A ⁸ has the following general formula (II)
An oxy (or thio) phenyl group represented by and a thiophenyl group represented by the following general formula (III). General formula (II):

[Chemical 2] General formula (III):

[Chemical 3] Q: O or S atom. R ^{1 to} R ⁵ : at least one is a linear or branched alkoxy group having a C number of 4 to 10, and the other are each independently a C number of 1 to 1.
0 straight-chain, branched or cyclic alkyl group, C number 1-3
An alkoxy group, a halogen atom or a hydrogen atom. R ⁶ to R ^10: independently linear C number of 1 to 10, branched or cyclic alkyl group, an alkoxy group having a C number of 1 to 3, halogen atom or a hydrogen atom. )

Further, according to the present invention, as a preferred embodiment, an optical recording medium provided with a light absorbing layer using an imidazole, a benzimidazole or a thiazole derivative as the nitrogen-containing compound (2) is also represented by the above general formula ( I)
A compound in which R ^{6 of the} phthalocyanine compound (1) represented by is one group selected from methyl, ethyl, n-propyl, iso-propyl, methoxy, ethoxy, n-propyloxy, and iso-propyloxy is used. The optical recording medium provided with the light absorption layer described above, and the light absorption layer having a light absorption peak wavelength (λm) in the range of 710 to 750 nm.
An optical recording medium is provided that has ax).

Furthermore, according to the present invention, a metal phthalocyanine compound represented by the above general formula (I) is directly or via another layer on a substrate having information pits and / or guide grooves formed on the surface thereof. A light absorbing layer containing a coordination bond of (1) and a nitrogen-containing compound (2) selected from an optionally substituted or cyclized amino compound, imino compound and azo compound as a main component is coated. A method for manufacturing an optical recording medium is provided, which is characterized in that it is provided by a film means, a light reflection layer is provided thereon by a vacuum film formation means directly or through another layer, and a protective layer is further provided thereon. .

The present invention will be described in detail below. In the optical recording medium of the present invention, the light absorbing layer is selected from the metal phthalocyanine compound (1) represented by the general formula (I) and optionally substituted or cyclized amino compound, imino compound and azo compound. And a coordination bond with the nitrogen-containing compound (2) as a main component. That is, in the optical recording medium of the present invention, the metal phthalocyanine compound (1) used in the light absorbing layer has a structure represented by the above general formula (I). As the central metal M, Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Zn ²⁺ and Cd ²⁺ can be used, and Zn ²⁺ is particularly preferable. The phthalocyanine-based compound (1) having these central metal ions has a center metal of -N = or -N in the nitrogen-containing compound (2).
<The group is easily coordinated and the phthalocyanine-based compound molecule is less likely to associate with each other, so that the solubility is good, and the write-once type C
A light absorption layer having a complex refractive index required for D can be formed.

Further, in the oxy (or thio) phenyl group represented by the following general formula (II) contained in the substituents represented by A ^{1 to} A ⁸ , Q represents an O or S atom, and R ¹ To R ⁵ are at least one linear or branched alkoxy group having a C number of 4 to 10, and the other independently have a C number of 1 to 1.
0 straight-chain, branched or cyclic alkyl group, C number 1-3
Represents an alkoxy group, a halogen atom or a hydrogen atom.

[Chemical 2]

Specific examples of the alkoxy group having a C number of 4 to 10 include n-butyloxy, iso-butyloxy and te.
rt-butyloxy, sec-butyloxy, n-pentyloxy, neo-pentyloxy, iso-pentyloxy, tert-pentyloxy, 1-methylbutyloxy, 2-methylbutyloxy, n-hexyloxy, cyclohexyloxy, adamantyloxy , Norbornyloxy, benzyloxy, and the like, but those having a branched alkoxy group in R ¹ and / or R ⁵ are preferable. This is because the compound having a branched alkoxy group in R ¹ and R ⁵ easily obtains a good complex refractive index (particularly high refractive index) in the laser light wavelength region. Specific examples of R ^{1 to} R ⁵ and others (R ^{1 to} R ⁵ which are not C 4-10 alkoxy groups) include a hydrogen atom, methyl, ethyl, n-propyl, iso-propyl and n-.
Butyl, iso-butyl, tert-butyl, sec-
Butyl, n-pentyl, iso-pentyl, tert-
Pentyl, neo-pentyl, 1-methylbutyl, 2-
Methylbutyl, n-hexyl, 2-ethylbutyl, cyclohexyl, methoxy, ethoxy, n-propyloxy, iso-propyloxy groups, F, Cl, B
r, each I atom, etc. are mentioned.

On the other hand, R ^{6 to} R ¹⁰ of the thiophenyl group contained in the substituents represented by A ^{1 to} A ⁸ and represented by the following general formula (III) may be the same or different. , R ^{6 to} R ¹⁰ each independently represent a linear, branched or cyclic alkyl group having a C number of 1 to 10, an alkoxy group having a C number of 1 to 3, a halogen atom or a hydrogen atom.

[Chemical 3]

Specific examples of R ^{6 to} R ¹⁰ include a hydrogen atom,
Methyl, ethyl, n-propyl, iso-propyl, n
-Butyl, iso-butyl, tert-butyl, sec
-Butyl, n-pentyl, iso-pentyl, tert
-Pentyl, neo-pentyl, 1-methylbutyl, 2
-Methylbutyl, n-hexyl, 2-ethylbutyl, cyclohexyl, methoxy, ethoxy, n-propyloxy, iso-propyloxy groups, F, Cl, B
Each of r and I atoms can be mentioned, but those having an alkyl group or an alkoxy group in R ⁶ and / or R ¹⁰ are preferable. This is because a compound having an alkyl group or an alkoxy group in R ⁶ and R ¹⁰ easily obtains a good complex refractive index (particularly high refractive index). In addition, in R ^{1 to} R ¹⁰ , the number of carbon atoms is 1
When it is larger than 0, the absorbance per unit film thickness of the light absorption layer is lowered, and it becomes difficult to obtain a good complex refractive index, which is not preferable.

The phthalocyanine compound represented by the general formula (I) can be easily synthesized by a cyclization reaction of a corresponding phthalonitrile mixture. That is, a mixture of the following (IV) and (V) is reacted by heating with a metal derivative in alcohol in the presence of, for example, 1,8-diazabicyclo [5,4,0] -7-undecene. Can be easily synthesized.

[Chemical formula 4]

[Chemical formula 5]

The ratio of the oxy (or thio) phenyl group represented by the general formula (II) to the thiophenyl group represented by the general formula (III) in A ^{1 to} A ⁸ is 1 /.
3 to 3/1 is preferable, and it is more preferable to form the light absorption layer with a mixture of compounds having a ratio in this range. When the ratio of the group of the general formula (II) is large, the pit length shift of the reproduction signal is likely to occur, and conversely, when the ratio of the group of the general formula (III) is large, the decomposition temperature of the dye is high and the recording sensitivity is likely to be lowered. . In addition, the use of the mixture improves the solubility of the dye and improves the film forming property of the light absorption layer.

[0017]

The nitrogen-containing compound (2) selected from the optionally substituted or cyclized amino compound, imino compound and azo compound used in the present invention has -N = in the molecule.
Alternatively, it is a compound having a -N <group. Specific examples thereof include, but are not limited to, the following compounds. Among these, a compound containing an N atom in the heterocycle is preferable because it has a high effect of preventing association of the metal phthalocyanine compound and is excellent in durability (heat resistance and light resistance). Further, from the viewpoint of maintaining the thermal stability of the light absorption layer, the nitrogen-containing compound preferably has a melting point of 150 ° C. or higher. Melting point 15
This is because when the temperature is lower than 0 ° C., the characteristics (especially optical characteristics) of the light absorption layer are likely to change in a high temperature and high humidity environment. Among them, particularly preferable are imidazole, benzimidazole and thiazole derivatives.

N-butylamine, n-hexylamine,
tert-butylamine, pyrrole, pyrrolidine, pyridine, piperidine, purine, imidazole, benzimidazole, 5,6-dimethylbenzimidazole, 2,
5,6-trimethylbenzimidazole, naphthimidazole, 2-methylnaphthimidazole, quinoline, isoquinoline, quinoxaline, benzquinoline, phenanthridine, indoline, carbazole, norharman,
Thiazole, benzthiazole, benzoxazole,
Benztriazole, 7-azaindole, tetrahydroquinoline, triphenylimidazole, phthalimide, benzisoquinoline-5,10-dione, triazine, perimidine, 5-chlorotriazole, ethylenediamine, azobenzene, trimethylamine, N, N-dimethylformamide, 1 ( 2H) phthalazinone, phthalhydrazide, 1,3-diiminoisoindoline, oxazole, polyimidazole, polybenzimidazole,
Polythiazole and the like.

Film in which the phthalocyanine compound (1) and the nitrogen-containing compound (2) are coordinate-bonded (light absorption layer)
Can be easily obtained by dissolving two compounds in a solvent and coating the solution as a coating solution on a substrate. Further, the mixing ratio of the phthalocyanine compound (1) and the nitrogen-containing compound (2) is a molar ratio of 1/2 to 2/1 [nitrogen-containing compound (2)
/ Ratio of phthalocyanine compound (1)] is preferable. When the molar ratio is less than 1/2, the effect of the nitrogen-containing compound cannot be sufficiently obtained, and when the molar ratio exceeds 2/1, the dye concentration in the film becomes low, and therefore the absorbance per unit film of the light absorbing layer is low. Is likely to decrease, and it becomes difficult to obtain a good complex refractive index (especially high refractive index).

The light absorbing layer of the present invention comprises an interaction (coordination bond) between the phthalocyanine compound (1) and the nitrogen-containing compound (2) and R ^{1 of the} phthalocyanine compound (1).
To R ⁶ (particularly R ² and R ⁶ ) are difficult to associate with the molecules of the phthalocyanine compound (1), and the absorption peak wavelength (λmax) of the light absorption layer is A ^{1 to} A ^{8 due to} the electron effect. Since it is in the range of 710 to 750 nm, it is possible to obtain the complex refractive index required for the write-once CD in the laser light wavelength range (760 to 800 nm). Furthermore, it is considered that the pit length deviation of the reproduced signal is unlikely to occur due to the thermal decomposition characteristics of A ^{1 to} A ⁸ .

As the material of the light absorbing layer, in addition to the phthalocyanine compound (1) and the nitrogen-containing compound (2), any dye conventionally known as a recording material of an information recording medium is mixed and used. be able to. Examples of such dyes include cyanine dyes, pyrylium / thiopyrylium dyes, azurenium dyes, squarylium dyes, metal complex salt dyes such as Ni and Cr, naphthoquinone / anthraquinone dyes, indophenol dyes, India Examples thereof include aniline type dyes, triphenylmethane type dyes, triallylmethane type dyes, aminium type / diimmonium type dyes, and nitroso compounds. Further, if necessary, other third component such as binder, stabilizer and the like can be contained. The thickness of the light absorbing layer is preferably 100 to 5000 Å, and particularly 5
A range of 00 to 3000Å is desirable. This is because if the thickness of the light absorbing layer is smaller than this range, the recording sensitivity is lowered, and if it is thicker, the reflectance is lowered.

The substrate used in the present invention can be arbitrarily selected from various materials used as substrates for conventional information recording media. Examples of substrate materials include
Examples thereof include acrylic resins such as polymethylmethacrylate, vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymer, epoxy resins, polycarbonate resins, amorphous polyolefins, polyesters, glasses such as soda lime glass, and ceramics. In particular, from the viewpoint of dimensional stability, transparency and flatness, polymethyl methacrylate, polycarbonate resin, epoxy resin, amorphous polyolefin, polyester, glass and the like can be mentioned.

On the surface of the substrate on which the light absorption layer is provided,
An undercoat layer may be provided for the purpose of improving flatness, improving adhesive strength, and preventing alteration of the light absorption layer. Examples of the material for the undercoat layer include polymethylmethacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylolacrylamide, styrene / sulfonic acid copolymer, styrene / Vinyltoluene copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate /
Vinyl chloride copolymer, ethylene / vinyl acetate copolymer,
Polymer substances such as polyethylene, polypropylene and polycarbonate: Organic substances such as silane coupling agents: and inorganic substances such as inorganic oxides (SiO ₂ , Al ₂ O ₃ etc.) and inorganic fluorides (MgF ₂ ). it can. The layer thickness of the undercoat layer is generally in the range of 0.005 to 20 μm, preferably 0.01 to 10 μm.

A pregroup layer may be provided on the substrate (or undercoat layer) for the purpose of forming a groove for tracking or an unevenness representing information such as an address signal. As the material for the pregroup layer, a mixture of at least one monomer (or oligomer) of acrylic acid monoester, diester, triester, and tetraester and a photopolymerization initiator can be used.

Further, a reflective layer may be provided on the light absorbing layer for the purpose of improving the S / N ratio, reflectance and sensitivity during recording. The light-reflecting substance that is the material of the reflecting layer is a substance having a high reflectance for laser light, and examples thereof include Mg, Se, Y, Ti, Zr, Hf, V,
Nb, Ta, Cr, Mo, W, Mn, Re, Fe, C
o, Ni, Ru, Rh, Pd, Ir, Pt, Cu, A
g, Au, Zn, Cd, Al, Ca, In, Si, G
Metals and semimetals such as e, Te, Pb, Po, Sn and Si can be mentioned. Among these, preferable ones are Au, Al and Ag. These substances may be used alone or in combination of two or more or as an alloy. The layer thickness of the reflective layer is generally 100 to
It is in the range of 3000Å. Further, the reflective layer may be provided between the substrate and the light absorbing layer, and in this case, recording / reproducing of information is performed from the light absorbing layer side (the side opposite to the substrate).

On the light absorption layer (or reflection layer),
A protective layer may be provided for the purpose of physically and chemically protecting the light absorbing layer and the like. This protective layer may be provided on the side of the substrate where the light absorption layer is not provided for the purpose of enhancing scratch resistance and moisture resistance. Examples of the material used for the protective layer include inorganic substances such as Si, O, SiO ₂ , MgF ₂ , and SnO ₂ , thermoplastic resin, thermosetting resin, and UV curable resin. The layer thickness of the protective layer is generally in the range of 500Å to 50 μm.

Next, a method of manufacturing the optical recording medium of the present invention will be described. The method for producing an optical recording medium of the present invention comprises a metal phthalocyanine compound represented by the general formula (I) directly or through another layer on a substrate having information pits and / or guide grooves formed on the surface. A light absorbing layer containing (1) and the nitrogen-containing compound (2) as main components is provided by coating film forming means, and a light reflecting layer is provided thereon by vacuum film forming means directly or via another layer, Further, it is characterized in that a protective layer is provided thereon. That is, the manufacturing method of the present invention comprises the following steps. (A) A metal phthalocyanine compound (1) represented by the general formula (I) directly or through another layer on a substrate having information pits and / or guide grooves formed on its surface.
And a step of providing a light absorption layer containing the above-mentioned nitrogen-containing compound (2) as a main component by coating and film formation means, and (b) a vacuum film formation means for forming the light reflection layer directly on the light absorption layer or through another layer. And the step of (c) providing a protective layer on the light absorption layer.

(Light Absorbing Layer Forming Step) In the method of the present invention, first, the metal phthalocyanine compound is directly or through another layer formed on a substrate having information pits and / or guide grooves formed on the surface thereof. A light absorption layer containing (1) and the nitrogen-containing compound (2) as main components is provided by a coating and film forming means. That is, the light absorption layer in the present invention comprises a film in which the phthalocyanine compound (1) and the nitrogen-containing compound (2) are coordinate-bonded, and the light absorption layer dissolves the above two compounds to form a liquid state. It can be easily obtained by coating a substrate as a coating liquid. As a solvent for preparing this coating solution, a known organic solvent (for example, alcohol, cellosolve, carbon halide, ketone, ether, etc.) can be used. As the coating method, the spin coating method is preferable because the layer thickness can be controlled by adjusting the concentration and viscosity of the light absorbing layer and the drying temperature of the solvent.

An undercoat layer is provided on the surface of the substrate on the side where the light absorbing layer is provided for the purpose of improving the flatness of the substrate surface, improving the adhesive strength, and preventing alteration of the light absorbing layer. . The undercoat layer in this case is prepared by, for example, dissolving or dispersing the above-mentioned undercoat layer substance in a suitable solvent to prepare a coating solution, and then spin-coating, dip-coating the coating solution.
It can be formed by coating the substrate surface by a coating method such as extrusion coating.

(Light-Reflecting Layer Forming Step) In the method of the present invention, a light-reflecting layer is then provided on the light-absorbing layer directly or via another layer by a vacuum film forming means. That is, the light reflecting layer is formed on the light absorbing layer by, for example, vapor deposition, sputtering or ion plating of the above-mentioned light reflecting substance.

(Protective Layer Forming Step) In the method of the present invention, a protective layer is provided on the light reflecting layer. That is, it is formed by vacuum film formation or application film formation of the protective layer material made of the above-mentioned inorganic substance or various resins. In particular, it is preferable to use a UV curable resin, which is formed by spin coating the resin and then irradiating it with ultraviolet rays to cure it.

[0033]

The present invention will be described below with reference to examples, but the present invention is not limited thereto.

Example 1 A substrate having a guide groove concavo-convex pattern having a depth of about 1400Å on the surface of a polycarbonate disk having a diameter of 120 mm and a thickness of 1.2 mm was prepared, and the following (1) in Table 1- (1) was used. −
A light absorbing layer composed of a coordination bond of a phthalocyanine compound represented by and 5,6-dimethylbenzimidazole [compound (1)-], using a mixed solvent of tetrahydrofuran, 2-butoxyethanol and methylcyclohexane as a coating liquid. It was provided by spin coating.
The phthalocyanine compound (1)-is prepared by mixing phthalonitrile having A and phthalonitrile having A'at a ratio (A / A '= 1/1) to prepare 1,8-diazabicyclo [5,4,0]. It was obtained by adding -7-undecene and metal chloride and heating and reacting in 1-pentanol. The mixing ratio of the compound (1)-and the compound (1)-was 1.0 in terms of a molar ratio [compound (1)-/ compound (1)-]. Λmax of the formed light absorption layer is 730
was nm. The thickness of the light absorption layer was about 1500Å. An optical recording medium of the present invention was prepared by providing Au on the light absorbing layer by Au sputtering to a thickness of about 800 Å to form a reflective layer, and further forming a protective layer of an ultraviolet curable resin on the light absorbing layer to a thickness of about 5 μm. Got

The obtained optical recording medium has a wavelength of 785 nm,
N. A. When the EFM signal was recorded and reproduced under the conditions of 0.5 and linear velocity of 1.2 m / s, the reflectance (Itop) was 74%,
The Cl error was 220 or less. Furthermore, when the pit length of the reproduced signal was measured using an interval analyzer, the pit length deviation from the standard CD (Test5B) was 40 ns or less, which was a value satisfying the write-once CD standard (Orange Book).

Examples 2 to 8 (However, Example 7 is a reference example.
is there. ) An optical recording medium of the present invention was produced under the conditions (2) to (8) in Table 1- (1 ) described below, and evaluated in the same manner as in Example 1. The results are shown in Table 1- (2).
It was in the range of 750 nm, and Itop, Cl error, and pit length deviation satisfied the write-once CD standard.

Comparative Examples 1 to 3 Comparative optical recording media were prepared under the conditions (9) to (11) in Table 2- (1) below, and evaluated in the same manner as in Example 1. The results are shown in Table 2- (2).
Although it was in the range of 750 nm, the reproduction signal characteristics were write-once type C
It was not possible to satisfy the D standard. Especially for the pit length deviation, 1 for samples (9) to (11)
It was -60 ns or less in 1 T pit, which was out of the standard.

[0038]

[Table 1- (1)]

[0039]

[Table 1- (2)]

[0040]

[Table 2- (1)]

[0041]

[Table 2- (2)]

[0042]

According to the optical recording medium of claim 1, the light absorbing layer is mainly composed of a coordination bond of the metal phthalocyanine compound (1) represented by the general formula (I) and the nitrogen-containing compound (2). Since it is composed as a component, it has excellent signal characteristics, is less likely to cause a reproduction error, and is excellent in light resistance.

In the optical recording medium of claim 2, since imidazole, benzimidazole or thiazole derivative is used as the nitrogen-containing compound (2), durability (light resistance, heat resistance) is further improved. Join.

In the optical recording medium of claim 3, R ⁶ of the phthalocyanine compound represented by the general formula (I) is
Independently methyl, ethyl, n-propyl, iso
Since it is selected from -propyl, methoxy, ethoxy, n-propyloxy, and iso-propyloxy, the effect of easily obtaining a good complex refractive index is added.

In the optical recording medium of claim 4, since the light absorption peak wavelength of the light absorption layer is in the range of 710 to 750 nm, an appropriate complex refractive index can be more reliably obtained at the laser light wavelength. The effect is added.

In the optical recording medium manufacturing method of the fifth aspect, the light absorbing layer is formed by the coating film forming means, and the light reflecting layer is formed by the vacuum film forming means. The medium can be easily and stably manufactured.

─────────────────────────────────────────────────── ───Continued from the front page (56) Reference JP-A-7-32737 (JP, A) JP-A-1-141955 (JP, A) JP-A-59-67093 (JP, A) JP-A-8- 300814 (JP, A) JP-A-8-2108 (JP, A) JP-A-7-334863 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41M 5/26 G11B 7 / 24 516 CAPLUS (STN) REGISTRY (STN) MARPAT (STN)

Claims (5)

(57) [Claims] 1. An optical recording medium comprising at least a light absorbing layer provided on a substrate, wherein the light absorbing layer has the following general formula (I):
And a nitrogen-containing compound (2) selected from optionally substituted or cyclized amino compounds, imino compounds and azo compounds represented by
An optical recording medium comprising a coordination bond with and as a main component. [Chemical 1] (In the formula, M and A ^{1 to} A ⁸ each represent the following: M: at least one metal ion selected from Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Zn ²⁺ and Cd ^2+. A ¹ and A ² , A ³ and A ⁴ , A ⁵ and A ⁶ and A ⁷ and A ⁸ : either one of them is an oxy (or thio) phenyl group represented by the following general formula (II) or the following: General formula (III)
A thiophenyl group represented by and the other is a hydrogen atom. However, at least one of A ^{1 to} A ⁸ has the following general formula (II)
An oxy (or thio) phenyl group represented by and a thiophenyl group represented by the following general formula (III). General formula (II): General formula (III): Q: O or S atom. R ^{1 to} R ⁵ : at least one is a linear or branched alkoxy group having a C number of 4 to 10, and the other are each independently a C number of 1 to 1.
0 straight-chain, branched or cyclic alkyl group, C number 1-3
An alkoxy group, a halogen atom or a hydrogen atom. R ⁶ to R ^10: independently linear C number of 1 to 10, branched or cyclic alkyl group, an alkoxy group having a C number of 1 to 3, halogen atom or a hydrogen atom. ) 2. The optical recording medium according to claim 1, wherein the nitrogen-containing compound (2) is an imidazole, a benzimidazole or a thiazole derivative. 3. R ^{6 of the} phthalocyanine compound (1) represented by the general formula (I) is methyl, ethyl or n-.
Propyl, iso-propyl, methoxy, ethoxy, n
The optical recording medium according to claim 1, which is one group selected from -propyloxy and iso-propyloxy. 4. The optical recording medium according to claim 1, wherein the light absorption layer has a light absorption peak wavelength (λmax) in a range of 710 to 750 nm. 5. Substitution with a metal phthalocyanine compound (1) represented by the general formula (I) directly or through another layer on a substrate having information pits and / or guide grooves formed on the surface thereof. Alternatively, a light absorption layer containing, as a main component, a coordination bond with a nitrogen-containing compound (2) selected from an optionally cyclized amino compound, imino compound and azo compound is provided by coating and film formation means, The optical recording medium according to any one of claims 1 to 4, wherein a light reflecting layer is provided on the above by a vacuum film forming means directly or through another layer, and a protective layer is further provided thereon. Manufacturing method.