JP2934065B2 - Information recording medium and optical information recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium and an optical information recording method capable of recording information using a high energy density laser beam.

[0002]

2. Description of the Related Art 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 video disk, an audio disk, a large-capacity still image file, a large-capacity computer disk memory, and the like.

[0003] A WO (Write Once) write-once optical disc has, as its basic structure, a disk-shaped substrate made of glass, synthetic resin, or the like, and Bi, Sn, and I provided thereon.
a recording layer comprising a metal or semimetal such as n or Te; or a dye such as cyanine, metal complex, or quinone. The substrate surface on the side where the recording layer is provided is usually
In order to improve the flatness of the substrate, the adhesion to the recording layer, or the sensitivity of the optical disk, an intermediate layer made of a polymer substance is often provided. Recording and reproduction of information on and from the optical disk are performed by irradiating a laser beam to the disk surface. At this time, the laser beam is usually applied to a predetermined position on the disk surface. A tracking guide (pre-groove) with a concave groove is provided in an annular shape (including a spiral shape) on the surface of the substrate in order to guide the laser beam and accurately follow the expected irradiation position (generally called tracking). Is common.

As described above, metals and dyes are known as a recording material for forming a recording layer. However, an information recording medium using a dye has higher sensitivity than a recording material such as a metal. Besides having advantages in the characteristics of the recording medium itself,
This has a great manufacturing advantage that the recording layer can be easily formed by a coating method. However, a recording layer made of a dye generally has a problem with characteristics such as low reflectance, a low degree of modulation of a reproduction signal, and a low C / N, and the dye recording layer is liable to deteriorate with time due to irradiation with light, and has light resistance. Has a drawback such as inferiority.

[0005] In the case of a WO-type optical disc, a CD-WO capable of recording a CD format signal at a high density requires 78
Using a laser having an oscillation wavelength of 0 nm, a constant linear velocity of 1.2
It is necessary to record the signal at a low speed of up to 1.4 m / sec. At that time, it is required that the recorded signal be reproduced by a commercially available CD player. For playback on a CD player, the reflectivity of the optical disc must be at least 70.
% Is desirable.

[0006] In order to increase the reflectivity, it is common practice to further provide a reflective layer on the dye recording layer.
One such example is Nikkei Electronics (p. 107, 19
Published on January 23, 1989). According to this, the dye used in the recording layer of the above recording medium is unknown, but the recording method is based on the absorption of laser light by the dye recording layer. Is melted, and accordingly, the plastic substrate is heated and the substrate rises to the recording layer side to form pits. This reflection layer is a deposited film of gold. Thereby, the reflectance can be improved.

Further, as described above, the dye recording layer generally has poor light resistance, and has a problem in that when it is stored in the presence of light, writing becomes impossible and the C / N of reading after recording deteriorates. . To improve such light fastness, an optical information recording medium containing a singlet oxygen quencher together with a cyanine dye is described in, for example, JP-A-59-55795. However, such a singlet oxygen quencher has a problem of lowering the C / N and the degree of modulation.

In order to obtain a dye recording layer having excellent light resistance,
An information recording medium using a phthalocyanine dye which is a dye having excellent light resistance is known. The recording layer of a phthalocyanine dye is generally formed by vacuum evaporation of the dye. However, if the recording layer is formed by an evaporation method, the advantage of the dye recording layer that can be formed by coating cannot be obtained. Accordingly, phthalocyanine-based dyes which can improve the solubility of the dye by introducing various substituents into the phthalocyanine and form a recording layer by coating have been disclosed (eg, JP-A No.
-265788, JP-A-2-138382, JP-A-2-39991, JP-A-1-103103
No. 88). This makes it possible to form the recording layer having excellent light resistance by a simple manufacturing method using coating. However, since these dyes have a large light absorption at 780 nm, they cannot be said to be suitable as a recording layer for the CD-WO which requires a high reflectance at 780 nm.

JP-A-2-87339 discloses a phthalocyanine dye whose metal is Co or TiCl ₂ ,
Although an optical disk for CD-WO in which a recording layer can be formed by coating and a high reflectance is obtained is disclosed, durability such as light resistance is not sufficient.

Therefore, a signal recorded with a laser having a wavelength of about 780 nm can be reproduced with a commercially available CD player, that is, with a laser having the same wavelength, a signal having a reflectance of 70% or more can be reproduced. An excellent information recording medium (CD-WO) has not been obtained.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide an information recording medium having a high reflectance, excellent recording / reproducing characteristics such as a degree of modulation, and excellent durability such as light resistance.

It is another object of the present invention to provide an information recording medium on which recorded signals can be reproduced by a commercially available CD player.

Another object of the present invention is to provide an information recording medium which has a ROM area (reproduction-only area) and a recordable area and is easy to manufacture.

Another object of the present invention is to provide an optical information recording method in which a recorded signal shows a high reflectance, a high degree of modulation, and excellent tracking characteristics by using a laser near 780 nm.

[0015] The above object is to provide a pre-groove and / or
Or, on a disc-shaped substrate provided with prepits, a recording layer made of a dye capable of recording information by laser and a reflective layer made of a metal, in an information recording medium in which the dye is laminated in this order, The following general formula (I): M (Pc) _m (I) [where M represents two hydrogen atoms, a metal, a metal oxide or a metal halide, and Pc represents the following general formula (I)
I):

Embedded image ｛Wherein W, X, Y and Z represent the 2-position of the benzene ring,
3-, 4-, or 5-substituents, each of which is a hydrogen atom or a general formula (IIIa) or (III
b):

Embedded image (However, in the general formula (IIIa), R ¹ is a hydrogen atom,
A represents an aliphatic group, an acyl group or a sulfonyl group, A represents a divalent aliphatic group, and R ² represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, an alkyl group, an acylamino group, and a sulfonylamino group. , Acyl group,
Represents an alkoxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an aryl group, an alkylsulfonyl group, a sulfonyl group, a heterocyclic group, an alkylthio group or an arylthio group, n ¹ represents an integer of 0 to 5, n ¹ is 2 In the above, R ² adjacently bonded on the benzene ring may be bonded to each other to form a 5- or 6-membered ring, and B represents an oxygen atom or a sulfur atom, and has the general formula (IIIb in), R ³ represents a hydrogen atom, an alkyl group, an acyl group or a sulfonyl group, R ⁴
Represents a halogen atom, an alkoxy group, an aryloxy group, an amino group, an alkylthio group or an arylthio group;
⁵ is hydrogen atom, halogen atom, alkyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, alkoxy group, aryloxy group, heterocyclic oxy group, acylamino group, anilino group, amino group, ureido group, sulfa Moiruamino group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfonamido group, a carbamoyl group, an acyl group, a sulfamoyl group, a sulfonyl group or an alkoxycarbonyl group, n ² represents an integer of 1 to 5, n ³ Represents an integer of 0 to 4, and substituents bonded adjacently on the benzene ring may be bonded to each other to form a 5- or 6-membered ring; , X, Y and Z are at least one of the above formulas (IIIa) and (IIIb). Represents on and m represents 1 or 2. And a phthalocyanine dye represented by the formula (1): Further, the information recording medium can be achieved by an optical information recording method comprising irradiating a laser having an oscillation wavelength in a range of 770 to 790 nm from the substrate side to record information.

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

2) The information recording medium, wherein the recording layer is a coating film.

3) The information recording medium as described above, wherein the recording layer has a light absorption of 5% or less at a wavelength of 780 nm.

4) The information recording medium as described above, wherein the substrate is formed with a read-only area composed of pre-pits and a recordable area composed of pre-grooves.

5) The information recording medium as described above, wherein M in the general formula (I) is a group IIIb atom.

6) M in the general formula (I) is Lu, Y
The information recording medium described above, which is at least one selected from the group consisting of b, Gd, and Eu.

(7) The information recording medium as described above, wherein a reflective layer and a protective layer are laminated on the recording layer in this order.

(8) The information recording medium as described above, wherein the recording layer has been subjected to a contact treatment with a solvent gas.

9) The difference between the optical thickness at the bottom of the pre-groove of the recording layer and the optical thickness at the portion between the pre-grooves (lands) is λ / 8 or less (λ: reproduction laser wavelength). The above information recording medium characterized by the above-mentioned.

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

1) The oscillation wavelength of the laser is 780 nm
The above optical information recording method, characterized in that:

2) The information recording medium, wherein the recording is performed while rotating the information recording medium at a constant linear speed of 1.2 to 1.4 m / min.

[Detailed Description of the Invention] The information recording medium of the present invention has a basic structure in which a recording layer made of a specific phthalocyanine dye and a reflective layer are laminated on a disk-shaped substrate.

The structure of the information recording medium of the present invention will be described with reference to FIG.

FIG. 1 is a sectional view showing an example of the information recording medium of the present invention.

On the surface of the disk-shaped substrate 11, a recordable area 16 composed of a pre-groove 15 is formed. On the pregroove, a recording layer 12 made of a specific phthalocyanine dye is formed by coating. On the recording layer, a reflective layer 13 made of metal is formed by vacuum evaporation or the like. The protective layer 14 is formed on the reflective layer. For example, a ROM area composed of prepits may be formed on the inner peripheral side of the recordable area.

As shown in FIG. 1, in the present invention, the recording layer 12 is formed on a pre-groove or a pre-groove by applying and forming the above-mentioned specific phthalocyanine dye having excellent solubility in a solvent and excellent light resistance. And on the pre-pits. As described above, since the optical disk of the present invention exhibits a particularly high reflectance near 780 nm by using the above-mentioned specific phthalocyanine dye, the
-Particularly useful for WO type optical discs. Further, by recording on the information recording medium using a laser having a wavelength of about 780 nm, it is possible to obtain a signal with a high reflectance, a high degree of modulation and a high C / N. In order to exhibit a particularly high reflectance near 780 nm, the dye recording layer of the present invention preferably has a light absorption of 5% or less at a wavelength of 780 nm. The light absorptance is determined by (100-reflectance) when a reflective layer is provided on the recording layer as described above. Furthermore, after forming the dye layer by coating and drying, it is preferable to expose to a solvent vapor using tetrahydrofuran or the like in order to improve the reflectance.

The information recording medium of the present invention can be manufactured, for example, as follows.

The disc-shaped substrate of the present invention can be arbitrarily selected from various materials used as conventional substrates for information recording media. Examples of the substrate material of the present invention include glass; polycarbonate; acrylic resins such as polymethyl methacrylate; polyvinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymer; epoxy resins; amorphous polyolefin and polyester; You may use together if desired. Note that these materials can be used in the form of a film or a rigid substrate. Among the above materials, polycarbonate is preferred from the viewpoint of moisture resistance, dimensional stability, cost, and the like.

An intermediate layer may be provided on the substrate surface of the information recording medium on the side where the recording layer is provided, for the purpose of improving flatness, improving adhesive strength, improving sensitivity and preventing deterioration of the recording layer. Good. Examples of the material of the intermediate layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer,
Styrene / anhydrous maleate copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, chlorosulfonated polyethylene,
High molecular substances such as nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate, comb-type graft polymer; and Organic substances such as dyes, silver acetylide compounds and silane coupling agents can be mentioned.

The intermediate layer is prepared, for example, by dissolving or dispersing the above substance in an appropriate solvent to prepare a coating solution, and then applying the coating solution to the substrate surface by a coating method such as spin coating, dip coating, or extrusion coating. Can be formed. The thickness of the undercoat layer is generally 0.1.
005 to 20 μm, preferably 0.01 to
It is in the range of 10 μm.

On the disc-shaped substrate of the present invention, a tracking pre-groove representing information such as address signals or music information is formed. Further, pre-pits may be formed as desired. When a resin material such as the above polycarbonate is used, pits and grooves are preferably provided directly on the substrate by injection molding or extrusion molding of the resin material.

The formation of a pre-groove or the like may be performed by providing a pre-groove layer. As a material for the pregroove 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. The pre-groove layer is formed by first applying a mixed solution composed of the above-mentioned acrylate and a polymerization initiator on a precisely formed master (stamper), and then placing a substrate on the coating solution layer. The liquid layer is cured by irradiating ultraviolet rays through the substrate or the matrix to fix the substrate and the liquid phase. Next, the substrate provided with the pre-groove layer is obtained by peeling the substrate from the matrix. The layer thickness of the pre-groove layer is generally 0.
In the range of from 0.5 to 100 μm, preferably from 0.1 to 5 μm.
The range is 0 μm.

On the disc-shaped substrate, the following general formula (I)
Is provided with a recording layer comprising a phthalocyanine dye represented by

M (Pc) _m (I) wherein M represents two hydrogen atoms, a metal, a metal oxide or a metal halide, and Pc represents the following general formula (I
I):

[0041]

Embedded image

Wherein W, X, Y and Z are substituents at the 2-, 3-, 4- or 5-position of the benzene ring, each of which is a hydrogen atom or the following general formula (IIIa) or ( IIIb):

[0043]

Embedded image

(However, in the general formula (IIIa), R ¹
Represents a hydrogen atom, an aliphatic group, an acyl group or a sulfonyl group, A represents a divalent aliphatic group, and R ² represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, an alkyl group, an acylamino group. , A sulfonylamino group, an acyl group, an alkoxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an aryl group,
Alkylsulfonyl group, a sulfonyl group, a heterocyclic group, an alkylthio group or an arylthio group, n ¹ is 0
When n ¹ is 2 or more, R ² adjacently bonded on the benzene ring is bonded to each other to form a 5-membered or 6-membered
B may represent an oxygen atom or a sulfur atom, and in the general formula (IIIb), R ³ represents a hydrogen atom, an alkyl group, an acyl group or a sulfonyl group, and R ⁴ represents a halogen atom. An atom, an alkoxy group, an aryloxy group, an amino group, an alkylthio group or an arylthio group, and R ⁵ is a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxyl group, an alkoxy group, an aryloxy group , Heterocyclic oxy group, acylamino group, anilino group, amino group, ureido group, sulfamoylamino group, alkylthio group, arylthio group, heterocyclic thio group, sulfonamide group, carbamoyl group, acyl group, sulfamoyl group, sulfonyl group or represents alkoxycarbonyl group, n ² is 1 to 5
And n ³ represents an integer of 0 to 4, and the substituents adjacently bonded on the benzene ring may be bonded to each other to form a 5- or 6-membered ring. And at least one of W, X, Y and Z represents a phthalocyanine divalent ion represented by｝ which is one of the above general formulas (IIIa) or (IIIb), and m is 1 or 2 Represents ]

The phthalocyanine dye represented by the above general formula (I) is disclosed as a novel compound in JP-A-63-280083, but there is no description on application to an optical disk. It has been found. Therefore, the above general formulas (I), (II) and (IIIa)
As for the specific examples of the substituents of (IIIb) and those described in the above publication, those described in the above publication can be applied to the present invention.

In the above general formula (I), M is, for example, Zn, Pb, Cu, Ni, Fe, Co, Sr, C
a, Yb, Ru, Sm, Tb, Dy, U, Tl, Cs,
Pd, Nd, Ga, In, Sn, Si, Pt, Mn, G
e, Al, V, VO, Mg, Ti, Cr, Mo, Lu,
Examples include Yb, Gd, Eu, AlCl ₂ , and SiCl ₂ . Generally, it is a group IIIb, IIA or VII atom, and among these, it is preferably a group IIIb atom, particularly preferably either a lanthanum or a lanthanide element, especially Lu, Yb, Gd or E.
It is preferably u.

In the general formula (IIIa), which is a preferred substituent of W, X, Y and Z in the general formula (II), R ¹ represents a hydrogen atom, an aliphatic group, an acyl group or a sulfonyl group; Examples thereof include a linear or branched alkyl group, alkenyl group, aralkyl group, cycloalkyl group, alkynyl group and cycloalkenyl group having 1 to 36 carbon atoms. Examples of the acyl group include an acetyl group, a propionyl group, a 2-methylpropionyl group, a benzoyl group, and a (2,4-di-tert-amylphenoxy) acetyl group. Examples of the sulfonyl group include a methanesulfonyl group, a benzenesulfonyl group, and (2
-Octyloxy-5-tert-octyl) phenylsulfonyl group.

The above-mentioned aliphatic group, acyl group and sulfonyl group may have the following substituents. For example, a halogen atom (eg, chlorine atom, bromine atom), an alkyl group (eg, methyl group, propyl group, i-butyl group, trifluoromethyl group, tridecyl group, 3- (2,4-di-t-amyl) Phenoxy) propyl group, 2-dodecyloxyethyl group, 3-phenoxypropyl group, 2-hexylsulfonyl-ethyl group, cyclopentyl group, benzyl group), aryl group (eg, phenyl group, 4-t-butylphenyl group, , 4-di-t-amylphenyl group, 4-tetradecanamidophenyl group), heterocyclic group (eg, 2-furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group), cyano group, alkoxy Groups (eg, methoxy group, ethoxy group, 2-methoxyethoxy group, 2-dodecyloxyethoxy group, 2-methanesulfonylethoxy group) Oxy group (e.g., phenoxy, 2-methylphenoxy group, 4-t-butyl phenoxy group), a heterocyclic oxy group (e.g., 2-benzimidazolyl group),
Acylamino group (eg, acetamido group, benzamide group, tetradecaneamide group, α- (2,4-di-t-amylphenoxy) butylamide group, γ- (3-t-butyl-4-hydroxyphenoxy) butylamide group, α −
{4- (4-hydroxyphenylsulfonyl) phenoxy} decaneamide group), anilino group (for example, phenylamino group, 2-chloroanilino group, 2-chloro-5-tetradecanamidoanilino group, 2-chloro-5-dodecyloxycarbonyl) Anilino group, N-acetylanilino group, 2-chloro-5- {α- (3-t-butyl-4-hydroxyphenoxy) dodecaneamide} anilino group,
Ureido group (for example, phenylureido group, methylureide group, N, N-dibutylureido group, etc.), imide group (for example, N-succinimide group, 3-benzylhydantoinyl group, 4- (2- Ethylhexanoylamino) phthalimide group, etc.), sulfamoylamino group (eg, N, N-dipropylsulfamoylamino group,
An N-methyl-N-decylsulfamoylamino group,
Etc.), alkylthio groups (e.g., methylthio, octylthio, tetradecylthio, 2-phenoxyethylthio, 3-phenoxypropylthio, 3- (4-t
-Butylphenoxy) propylthio group, etc.), arylthio group (for example, phenylthio group, 2-butoxy-5-
t-octylphenylthio group, 3-pentadecylphenylthio group, 2-carboxyphenylthio group, 4-tetradecanamidophenylthio group, etc.), heterocyclic thio group (eg, 2-benzothiazolylthio group, etc.) , Sulfonamide group (for example, methanesulfonamide group, hexadecanesulfonamide group, benzenesulfonamide group,
p-toluenesulfonamide group, octadecanesulfonamide group, 2-methyloxy-5-t-butylbenzenesulfonamide group, etc.), carbamoyl group (for example, N
-Ethylcarbamoyl group, N, N-dibutylcarbamoyl group, N- (2-dodecyloxyethyl) carbamoyl group, N-methyl-N-dodecylcarbamoyl group, N-
{3- (2,4-di-tert-amylphenoxy) propyl} carbamoyl group, etc.), acyl group (for example, acetyl group (2,4-di-tert-amylphenoxy))
Acetyl group, benzoyl group, etc.), sulfamoyl group (for example, N-ethylsulfamoyl group, N, N-dipropylsulfamoyl group, N- (2-dodecyloxyethyl) sulfamoyl group, N-ethyl-N- Dodecylsulfamoyl group, N, N-diethylsulfamoyl group,
Etc.), sulfonyl group (for example, methanesulfonyl group, octanesulfonyl group, benzenesulfonyl group, toluenesulfonyl group, etc.), alkoxycarbonyl group (for example, methoxycarbonyl group, butyloxycarbonyl group, dodecylcarbonyl group, octadecylcarbonyl group, Etc.).

In these, R ¹ is a hydrogen atom, —SO
_{2 - (n-C 5 H} 17) is preferable.

The divalent aliphatic group represented by A is a linear or cyclic alkylene group having preferably 1 to 22 carbon atoms (for example, a methylene group, a propylene group, a propylidene group, a tritylidene group, a cyclohexylidene group) ,
Represents a 1,1-propylene group, an ethylene group, a 1,3-propylene group, a 1,6-cyclohexylene group, a hexylmethylene group, etc., and A represents an alkyl group, an aryl group, a heterocyclic group, an alkoxy group (for example, Methoxy group, 2-methoxyethoxy group, etc.), aryloxy group (eg, phenoxy group, 2,4-di-tert-amylphenoxy group, 2-chlorophenoxy group, etc.), carbonyl group (eg, acetyl group, benzoyl group, etc.) ), Ester groups (eg, methoxycarbonyl group, phenoxycarbonyl group, acetoxy group, benzoyloxy group, butoxyl sulfonyl group, toluenesulfonyloxy group, etc.), amide group (eg, acetylamino group, ethylcarbamoyl group, dimethylcarbamoyl group) , Methanesulfonamide group, butylsulfamoy Group, etc.), sulfamide groups (for example, di-bromide Pils sulfamoyl amino group),
Imide group (eg, succinimide group, hydantoinyl group, etc.), ureido group (eg, phenylureido group,
A dimethylureido group, a sulfonyl group (eg, a methanesulfonyl group), a hydroxy group, a cyano group, a nitro group, a halogen atom thio group (eg, an ethylthio group,
Phenylthio group, etc.).

In these, A is —CH (nC ₆ H)
_{13) -, - CH (n} -C 12 H 25) -, - CH (C 2 H
_{5) -, - (CH 2} ) 3 -, - CH 2 -, - CH (n-
It is preferably C ₈ H ₁₇ ) — or —C (CH ₃ ) ₂ —.

R ² represents a halogen atom, a hydroxy group, a cyano group, a nitro group, an alkyl group (eg, a methyl group, a butyl group, a dodecyl group, etc.), an acylamino group (eg,
Acetylamino group, benzoylamino group, tetradecaneamide group, α- (2,4-di-t-amylphenoxy)
Butylamide group, γ- (3-t-butyl-4-hydroxyphenoxy) butylamide group, α- {4- (4-hydroxyphenylsulfonyl) phenoxy} decaneamide group, etc., sulfonylamino group (for example, butylsulfonamide group) Benzenesulfonamide group, methanesulfonamide group, hexadecanesulfonamide group, p-toluenesulfonamide group, octadecanesulfonamide group, 2-methoxy-5-t-butylbezenesulfonamide group, etc.), acyl group ( For example, an acetyl group, a benzoyl group, etc.), an aryl group, a heterocyclic group, an alkoxy group (eg, a methoxy group, a 2-methoxyethoxy group, etc.), an aryloxy group (eg, a phenoxy group, 2,
4-di-tert-amylphenoxy group, 2-chlorophenoxy group and the like, alkoxycarbonyl (for example, methoxycarbonyl group, phenoxycarbonyl group, acetoxy group, benzoyloxy group, butoxysulfonyl group,
A carbamoyl group (eg, an ethylcarbamoyl group, a dimethylcarbamoyl group, a sulfamoyl group, a butylsulfamoyl group, a dioctylsulfamoyl group, etc.), an alkylsulfonyl group or an arylsulfonyl group (eg, a methanesulfonyl group) , A p-hydroxyphenylsulfonyl group, etc.), a thio group (eg, an ethylthio group, a phenylthio group, etc.), and the substitutable group of R ² may be substituted with the substituent described in A, etc. n ¹ represents an integer of 0 to 5.

In these, R ² is Cl,-(t-C
_{5 H 11), - (C} 8 H 17), - (n-C 15 H 31), - C
_{H (C 2 H 5) -} , - (t-C 8 H 17), a phenyl group,
-CN, the following IIIa-1, IIIa-2 or the following IIIa-
It is preferably 3. n is preferably 1 to 3.

[0054]

Embedded image

[0055]

Embedded image

[0056]

Embedded image

In the general formula (IIIa), the cyano group represented by R ² is substituted at the ortho-position or the rose-position with respect to the —NR ¹ -CO-AB- group, and the halogen atom is substituted at the ortho-position. preferable. B is preferably a sulfur atom.

In the general formula (IIIb), R ³ represents a hydrogen atom, a substituted or unsubstituted alkyl group (for example, methyl, ethyl, n-hexyl, 2-ethylhexyl, 2-dodecyloxyethyl) Benzyl group, 2-methanesulfonylethyl group, etc.), acyl group (eg, acetyl group, phenoxyacetyl group, benzoyl group, dodecanoyl group, etc.), sulfonyl group (eg, methanesulfonyl group, octanesulfonyl group, benzenesulfonyl group,
It represents a (2-octyloxy-5-tert-octyl) phenylsulfonyl group or the like, and these may be bonded to the following substituents.

Among them, R ³ is preferably a hydrogen atom, a methyl group or —OC (nC ₅ H ₁₁ ).

R ⁴ is a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.), a substituted or unsubstituted alkoxy group [this alkyl residue may be linear or branched, or Or a saturated alkyl residue or an unsaturated alkyl residue] (for example, methoxy, butoxy, hexyloxy, octyloxy, allyloxy, 2-dodecylthioethoxy) Group, 2-propynoxy group, 2-methoxyethoxy group, 2- (N, N-diethylamino) ethoxy group,
Etc.), aryloxy group (for example, phenoxy group, 2-
Methoxyphenoxy group, 4-tert-butylphenoxy group, 2-phenylphenoxy group, etc.), amino group (for example, amino group, N, N-dimethylamino group, N-methyl-N-butylamino group, pyrrolidinyl group, morpholino) Group, N-methylanilino group, 2-chloroanilino group, 2
-Methoxy-5-methylanilino group, N, N-dibutylamino group, N, N-bis (2-propyloxyethyl)
Amino group, etc.), substituted or unsubstituted alkylthio group [this alkyl residue may be linear or branched, or may be cyclic] (for example, dodecylthio group, 2-
Butoxyethylthio group, 2- (N, N-diethyl) aminoethylthio group, 2- [2- (2-ethoxy) ethoxy] ethylthio group, etc., or arylthio group (for example, phenylthio group, 2-butoxyphenyl) Thio group, 4
-Tert-octylphenylthio group, 2-butoxy-
5-tert-octylphenylthio group, etc.).

In these, R ⁴ is —O (nC ₈ H)
_{17), - O (n-} C 12 H 25), - O (n-C 16 H 33),
_{-S (n-C 8 H 17} ), - CO 2 (n-C 12 H 25), -
_{O (CH 2) 2 O (} CH 2) 2 OCH 3, -O (CH
_{2) 2} OCH ₃ or -O (CH ₂₎ is preferably a ₂ OC ₂ H _5.

R ⁵ is a hydrogen atom, a halogen atom (for example,
A chlorine atom, a bromine atom, a fluorine atom, etc.), a substituted or unsubstituted alkyl group (for example, methyl group, ethyl group, i-propyl group, t-butyl group, trifluoromethyl group, dodecyl group, 3- (2, 4-di-tert-amylphenoxy) propyl group, allyl group, 2-dodecyloxyethyl group, cyclopentyl group, benzyl group, etc., aryl group (for example, phenyl group, 4-t-butylphenyl group,
2,4-di-t-amylphenyl group, 4-tetradecanamidophenyl group, etc.), heterocyclic group (for example, 2-furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group, etc.) , Cyano group, hydroxyl group,
A substituted or unsubstituted alkoxy group (for example, a methoxy group,
Ethoxy group, i-propoxy group, 2-methoxyethoxy group, 2-dodecyloxyethoxy group, 2-methanesulfonylethoxy group, etc., aryloxy group (for example, phenoxy group, 2-methylphenoxy group, 4-t- Butylphenoxy group, etc.), heterocyclic oxy group (for example, 2-
Benzimidazolyloxy group, etc.), acylamino group (for example, acetamido group, benzamido group, tetradecanamido group, α- (2,4-di-t-amylphenoxy) butylamide group, γ- (3-t-butyl-4) -Hydroxyphenoxy) butyramide group, α- {4- (4-
Hydroxyphenylsulfonyl) phenoxydidecamide group, etc.), anilino group (for example, phenylanilino group, 2-chloroanilino group, 2-chloro-5-tetradecanamidoanilino group, 2-chloro-5-dodecyloxycarbonylanilino group) Group, N-acetylanilino group, 2
-Chloro-5- {α- (3-t-butyl-4-hydroxyphenoxy) dodecaneamide} anilino group, etc.), amino group (for example, ethylamino group, dimethylamino group,
A ureido group (eg, phenylureido group, methylureido group, N, N-dimethylureido group, N, N dibutylureido group, etc.), a sulfamoylanomo group (eg, N, N-dipropylsulfamoylamino group, N-methyl-N-decylsulfamoylamino group, etc., substituted or unsubstituted alkylthio groups (for example, methylthio group, octylthio group, tetradecylthio group, 2-phenoxy) An ethylthio group, a 3-phenoxypropylthio group, a 3- (4-t-butylphenoxy) propylthio group, and the like, an arylthio group (for example,
A phenylthio group, a 2-butoxy-5-t-octylphenylthio group, a 3-pentadecylphenylthio group, a 2-carboxyphenylthio group, a 4-tetradecanamidophenylthio group, and the like; a heterocyclic thio group (for example, 2 -Benzothiazolylthio group, etc.), substituted or unsubstituted alkoxycarbonylamino group (for example, methoxycarbonylamino group, tetradecyloxycarbonylamino group,
Amide group (for example, methanesulfonamide group, hexadecanesulfonamide group, benzenesulfonamide group, p-toluenesulfonamide group, octadecanesulfonamide group, 2-methoxy-5-t-butylbenzenesulfonamide group, etc.) ), A carbamoyl group (eg, N
-Ethylcarbamoyl group, N, N-dibutylcarbamoyl group, N- (2-dodecylthioxyethyl) carbamoyl group, N-methyl-N-dodecylcarbamoyl group, N-
{3- (2,4-di-tert-amylphenoxy) propyl} carbamoyl group, etc., acyl group (eg, acetyl group, (2,4-di-tert-amylphenoxy) acetyl group, benzoyl group, etc.) ), A sulfamoyl group (eg, N-ethylsulfamoyl group, N, N-dipropylsulfamoyl group, N- (2-dodecyloxyethyl) sulfamoyl group, N-ethyl-N-dodecylsulfamoyl group, N , N-diethylsulfamoyl group, etc.), sulfonyl group (eg, methanesulfonyl group, octanesulfonyl group, benzenesulfonyl group, toluenesulfonyl group, etc.), substituted or unsubstituted alkoxycarbonyl group (eg, methoxycarbonyl group, Butyloxycarbonyl group, dodecyloxycarbonyl group,
Octadecyloxycarbonyl group, etc.).

In these, R ⁵ is-(tC _{8
H 17), - (t-} C 4 H 9), - O (n-C 8 H 17),
—NHSO ₂ (nC ₁₆ H ₃₃ ), the above IIIa-2,
It is preferably IIIb-1 or the following IIIb-2.

[0064]

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[0065]

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The more preferable formula (IIIb) is
R ⁴ is an alkoxy group or an aryloxy group, and —NR ³ —
It is bonded to the ortho position of the SO ₂ — group.

Among the above phthalocyanine dyes, the absorption maximum of the solution spectrum of each dye is 650 to 750 nm.
Are preferable, and those having a wavelength of 680 to 720 nm are particularly preferable.

In the general formula (II), when W, X, Y and Z are the same, B is O (oxygen atom) and n ¹ = 1, the general formula (III)
a) is preferred.

It is preferred that W, X, Y and Z in the general formula (II) be the same as the general formula (IIIb) when n ² = 1 and n ³ = 1.

A general method for synthesizing the phthalocyanine dye is described in JP-A-63-280083.

The dye recording layer is formed by the above-mentioned dye and, if desired, a binder, a metal complex salt dye or an aminium dye.
The coating can be performed by dissolving a diimmonium-based dye (quencher) in a solvent to prepare a coating solution, then applying the coating solution to the substrate surface to form a coating film, and then drying. After coating and drying the dye coating solution, it is preferable to form the recording layer by further exposing the coating film to solvent vapor.

Examples of the solvent for preparing the dye coating liquid include aliphatic hydrocarbons such as cyclohexane, methylcyclohexane, dimethylcyclohexane, n-hexane, n-heptane and n-octane; and aromatic hydrocarbons such as benzene, toluene and xylene. Hydrogen, ethyl acetate, butyl acetate, esters such as cellosolve acetate, methyl ethyl ketone,
Cyclohexanone, ketones such as methyl isobutyl ketone, dichloromethane, 1,2-dichloroethane, halogenated hydrocarbons such as chloroform, ethers such as tetrahydrofuran, ethyl ether, dioxane, ethanol, n-propanol, isopropanol, alcohols such as n-butanol, Examples include amides such as dimethylformamide, and fluorine-based solvents such as 2,2,3,3-tetrafluoropropanol. These may be used alone or may be used as a mixture if necessary. Various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be further added to the coating solution according to the purpose.

When a binder is used, the binder may be
For example, gelatin, nitrocellulose, cellulose derivatives such as cellulose acetate, dextran, rosin, natural organic high molecular substances such as rubber; and hydrocarbon resins such as polyethylene, polypropylene, polystyrene and polyisobutylene, polyvinyl chloride, polyvinylidene chloride, Vinyl resins such as polyvinyl chloride / polyvinyl acetate copolymers,
Synthetic organic polymers such as acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyolefins, epoxy resins, butyral resins, rubber derivatives, and initial condensates of thermosetting resins such as phenol and formaldehyde resins Substances can be mentioned. Spray method, spin coating method,
Examples thereof include a dip 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 dye layer, the ratio of the dye to the binder is generally in the range of 0.01 to 99% (weight ratio), preferably in the range of 1.0 to 95% (weight ratio). It is in.

It is preferable to form a recording layer by further contacting the coating film obtained by applying and drying the dye coating solution with a solvent gas as described above. As the solvent, it is preferable to use the solvent used for the dye coating solution or a solvent having a high dye-solubility such as tetrahydrofuran. The method for contacting the coating film with the solvent gas can be performed, for example, by holding or moving the substrate having the coating film in an atmosphere containing the gas. Thereby, the reflectance of the dye recording layer can be further improved. In particular, among the phthalocyanine dyes of the present invention, if the M (metal) is a metal or metal compound other than Group IIIb and the reflectance at 780 nm is not so high, the above treatment is highly effective in improving the reflectance.

The dye recording layer may be a single layer or a multilayer, and the layer thickness is generally in the range of 10 to 550 nm, preferably in the range of 20 to 300 nm. Also,
The light absorption at a wavelength of 780 nm is preferably 5% or less, and particularly preferably 3% or less. By doing this, 7
When recording or reproduction is performed with a laser having a wavelength of about 80 nm, a high reflectance can be obtained.

As described above, in the present invention, since a specific phthalocyanine dye having excellent light resistance is used for the recording layer as a recording material, the optical disk obtained has excellent light resistance, and a reflective layer is formed on the recording layer. Since it is provided, the reflectance is also improved. Further, by using the above-mentioned specific phthalocyanine-based dye, it exhibits a particularly high reflectance around 780 nm and is particularly useful for CD-WO type optical discs.
Further, by recording on the information recording medium using a laser having a wavelength of about 780 nm, a high reflectance can be obtained during reproduction, and a high degree of modulation and a large tracking servo gain can be obtained. Further, in the present invention, the thickness of the dye recording layer at the bottom of the pre-groove of the substrate and the thickness of the dye recording layer at the land are substantially the same on the pre-groove or the pre-pit by a specific coating method. This is preferable because the depth of the pre-groove of the substrate can be reduced, and an information recording medium having both a high degree of modulation and a high reflectance can be obtained. In addition, since the thickness of the dye layer at the bottom of the prepit and the thickness of the dye layer at the portion between the prepits are substantially the same, the phase difference between the prepits becomes large, and an information recording medium having a large modulation degree for the prepits can be obtained. . In particular, even if a dye recording layer is formed in a read-only area (ROM area) composed of pre-pits, the degree of modulation of the pre-pits is large. Therefore, the dye recording layer should be formed in both the read-only area and the recording area composed of pre-grooves. This makes it possible to obtain an effect that manufacturing of an optical disk having both a read-only area and a recording area becomes easy.

A method of forming the film thickness of the pre-pit and the pre-groove at the bottom portion and the inter-portion portion substantially the same is disclosed in Japanese Patent Application No. Hei.
No. 191257 can be used. As a solvent for the dye coating solution, a good solvent for the dye to be used (preferably, a solvent capable of dissolving the dye to be used at 2% by weight or more at the coating temperature of the dye solution) and a poor solvent for the dye to be used (preferably, a dye solution) (A solvent that does not dissolve the dye used in the coating temperature of 2% by weight or more). At this time, the good solvent and the poor solvent are compatible, and it is necessary that the evaporation rate of the poor solvent is not higher than the evaporation rate of the good solvent at the application temperature.

When the above-mentioned dye coating solution is applied onto a substrate by a spin coating method, it can be performed using a device and a method known per se. The above-mentioned dye solution is generally used at 0 to 100 ° C, particularly at 5 to 80 ° C, more preferably at 10 to 6 ° C.
It is preferred to apply at a temperature of 0 ° C. The number of rotations of the substrate is generally 10 to 1000 when the dye solution is applied.
rpm, particularly preferably 100 to 500 rpm. When the dye coating is dried, it is generally 300 to 100 rpm.
00 rpm, especially 500-7000 rpm, more particularly 7
It is preferably set to 00 to 4000 rpm.

A reflection layer is provided on the dye recording layer. The light-reflective substance that is the material of the reflection layer is a substance having a high reflectance to laser light, and examples thereof include Mg, Se, and the like.
Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo,
W, Mn, Re, Fe, Co, Ni, Ru, Rh, P
d, Ir, Pt, Cu, Ag, Au, Zn, Cd, A
1, Ga, In, Si, Ge, Te, Pb, Po, S
Metals and metalloids such as n and Bi can be mentioned. Preferred among these are Al, Au, Cr and Ni. These substances may be used alone or in combination of two or more kinds or as an alloy.

The reflective layer can be formed on the substrate by, for example, vapor deposition, sputtering or ion plating of the above-mentioned light reflective substance. The thickness of the reflective layer is generally in the range from 10 to 300 nm.

Further, an enhancement layer may be provided between the dye recording layer and the reflection layer. Examples of the material include a comb-type graft polymer (eg, macromer (manufactured by Toa Gosei Chemical Industry Co., Ltd.)), silver acetylide, and the like. Of course, such an enhancement layer may be provided on the metal recording layer.

A protective layer is preferably provided on the reflective layer for the purpose of physically and chemically protecting the recording layer and the like. This protective layer may be provided on the side of the substrate on which the recording layer is not provided for the purpose of improving the scratch resistance and the moisture resistance. Examples of the material used for the protective layer include SiO, Si
Inorganic substances such as O ₂ , MgF ₂ , SnO ₂ , Si ₃ N ₄ ;
Organic substances such as a thermoplastic resin, a thermosetting resin, and a UV curable resin can be given.

The protective layer can be formed, for example, by laminating a film obtained by extrusion of a plastic on a recording layer (reflection layer) and / or a substrate via an adhesive layer. Alternatively, it may be provided by a method such as vacuum deposition, sputtering, or coating. Also,
In the case of a thermoplastic resin or a thermosetting resin, they can also be formed by dissolving these in an appropriate solvent to prepare a coating solution, applying the coating solution, and drying. In the case of a UV-curable resin, it can also be formed by preparing a coating solution as it is or by dissolving it in an appropriate solvent, applying the coating solution, and irradiating with UV light to cure. Various additives such as an antistatic agent, an antioxidant, and a UV absorber may be added to these coating solutions according to the purpose. When the protective layer forming material is applied directly on the recording layer, a polybutadiene or the like is applied on the recording layer to protect the recording layer from the dissolving effect of the coating liquid for the protective layer (in this case, a solvent which does not dissolve the recording layer) Is preferable to provide an intermediate layer. The intermediate layer may be provided by depositing a thin film of metal or the like. The thickness of the protective layer is generally in the range from 0.1 to 100 μm.

Further, instead of forming the protective layer on the dye recording layer, the recording layer may be protected by fusing a plastic film on the inner and outer circumferences of the substrate on the recording layer. .

In the present invention, the information recording medium may be a single plate having the above-described structure, or two substrates having the above-described structure may be arranged such that the recording layer is on the inside and an adhesive or the like. By using the bonding method, a bonding type recording medium can be manufactured. Alternatively, an air sandwich type recording medium is manufactured by joining a substrate having the above configuration to at least one of the two disk-shaped substrates via a ring-shaped inner spacer and a ring-shaped outer spacer. You can also.

The optical information recording method of the present invention can be carried out as follows using the information recording medium obtained above.

First, the information recording medium is set at a constant linear velocity (1.2 to 1.4 m / cm in the case of the EFM signal of the CD format).
The recording light such as a semiconductor laser beam is irradiated from the substrate side while rotating at a constant angular velocity or a second. A laser beam having an oscillation wavelength in the range of 770 to 790 nm is used. By irradiation with light, pits are formed at the interface between the recording layer and its upper and lower layers (for example, void formation in the recording layer, deformation of the substrate (when the dye sublimation temperature is high), or change in the association state of the recording layer ( It is considered that the refractive index is changed by performing the dyeing or the like which easily forms an association, and the information is recorded. According to the recording method of the present invention, by recording using a laser having the above-mentioned oscillation wavelength, a high reflectance can be obtained at the time of reproduction, and a high degree of modulation and a large tracking servo gain can be obtained.

In reproducing the information recorded as described above, generally, the information recording medium is irradiated from the substrate side with a laser beam having the same wavelength as during recording while rotating the information recording medium at the same constant line (or constant angle) speed as described above. Then, it can be performed by detecting the reflected light. In addition, in the case of a flexible disk or the like, laser irradiation is sometimes performed from the recording layer side.

[0089]

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

[Example 1] A disc-shaped polycarbonate substrate (outer diameter: 120 mm, inner diameter: 15 mm, thickness: 1.2)
mm, refractive index: 1.58, pregroove (40 to 1 in diameter)
16 mm area, track pitch: 1.6 μm, half width:
0.5 μm, depth: 90 nm) was prepared as a substrate of an optical disk.

Dye A (phthalocyanine Lu complex) having the following structural formula was dissolved in methylcyclohexanone to prepare a dye coating solution having a concentration of 3% by weight.

Dye A:

[0093]

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This coating solution was applied onto the substrate by spin coating at a speed of 200 rpm for 4 seconds.
Increase the speed to 700 rpm by 50 rpm per second,
The dye was dried by holding at 00 rpm for 30 seconds to form a dye recording layer having a layer thickness of 130 nm.

On the dye recording layer, Au was DC-sputtered (deposition rate: 2 nm / sec, Ar pressure: 2 Pa,
(Power: 480 W, target-substrate distance: 95 mm) to form a reflective layer having a thickness of 100 nm.

Further, an ultraviolet curable resin (trade name: 3070, manufactured by Three Bond Co.) was applied on the reflective layer at a rotation speed of 200 rpm by a spin coating method, and then leveled at a rotation speed of 1500 rpm for 30 seconds. It was cured by irradiating it with a high-pressure mercury lamp (200 W / cm) for 10 seconds to form a protective layer having a thickness of 2 μm.

Thus, an information recording medium comprising the substrate, the dye recording layer, the reflection layer and the protective layer was manufactured.

Example 2 In Example 1, Dye B having the following structure (a phthalocyanine Mg complex in which Lu of the phthalocyanine Lu complex of Dye A was changed to Mg) was used in place of Dye A in Example 1, After forming the dye recording layer, the dye layer was exposed to tetrahydrofuran vapor for 10 minutes,
Then, an information recording medium was manufactured in the same manner as in Example 1 except that drying was performed at 80 ° C. for 30 minutes.

Dye B:

[0100]

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Comparative Example 1 An information recording medium was manufactured in the same manner as in Example 1, except that Dye C having the following structure was used instead of Dye A as the dye.

Dye C:

[0103]

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[Comparative Example 2] In Comparative Example 1, after forming the dye recording layer, the dye layer was placed in steam of tetrahydrofuran.
An information recording medium was manufactured in the same manner as in Comparative Example 1 except that the medium was exposed to light for 30 minutes and dried at 80 ° C. for 30 minutes.

Comparative Example 3 An information recording medium was manufactured in the same manner as in Example 1, except that Dye D having the following structure was used instead of Dye A as the dye.

Dye D:

[0107]

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[Comparative Example 4] In Comparative Example 3, after forming the dye recording layer, the dye layer was set in 10 vapors of tetrahydrofuran.
An information recording medium was produced in the same manner as in Comparative Example 3 except that the medium was exposed to light for 30 minutes and dried at 80 ° C. for 30 minutes.

Comparative Example 5 An information recording medium was manufactured in the same manner as in Example 1, except that Dye E having the following structure was used instead of Dye A as the dye.

Dye E:

[0111]

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The pregroove depth of the substrate and the thickness of each layer were obtained by measuring the cross section with an ultra-high resolution SEM (scanning electron microscope, S900 manufactured by Hitachi, Ltd.). .

[Evaluation of Information Recording Medium] With respect to the information recording medium obtained above, an optical disk evaluation machine DDU1000
(Pulstec Industrial Co., Ltd .; laser oscillation wavelength is 7
Recording was performed on the bottom of the pre-groove at a recording power of 6 mW and a constant linear velocity of 1.3 m / sec using an optical head of 80 nm and NA of 0.5) and an EFM encoder (KEN-WOOD).

1) Pre-groove reflectivity Mirror (a smooth surface area without pre-grooves and pre-pits) reflectivity is measured by using a spectrophotometer (UV13 manufactured by Shimadzu Corporation) with reference to an Al plate having a known reflectivity.
0). Then, the reflectance of the mirror portion was used as a reference and measured using a disk evaluation device.

2) Pre-groove reflectivity after recording It was determined in the same manner as in 1) above.

3) Degree of 11T modulation Among the CD format signals recorded in the pre-pit portion, the DC reproduction signal having a recording length of 11T is measured for the signal intensity of the signal portion and the mirror portion (the portion without signal), and the modulation is performed. The degree (C) was determined from the following equation. (SH: maximum signal strength, SL: minimum signal strength)

4) Light fastness In each of the above examples, the information recording medium on which only the recording layer before forming the reflective layer and the protective layer was irradiated with a Xe lamp for 20 minutes, and the absorbance at the absorption maximum before and after the irradiation was measured. SPEDTRO MULTI PHOTO DETECTOR; MCPD-100,
The change was determined by the following equation. ΔAbs (t = 0): initial absorbance ΔAbs (t = 20min.): Absorbance of Xe lamp irradiation for 20 minutes

Table 1 shows the results.

[0119]

[Table 1]

As is clear from the above results, the information recording media of Examples 1 and 2 using the phthalocyanine dye having a specific substituent of the present invention as a recording material are not only excellent in light resistance but also in reflection. The rate is high and the degree of modulation is also large. The recording media of Comparative Examples 1 to 4 are excellent in light resistance, but are particularly inferior in reflectivity to the recording media.
The recording medium of Comparative Example 5 has a relatively high reflectance, but does not have a sufficient degree of modulation and light resistance, and is particularly inferior in light resistance.

[0121]

The information recording medium of the present invention is a recording layer formed by applying a phthalocyanine dye having a specific substituent on a substrate having a pregroove and / or a prepit, and a reflective layer made of metal. Have a laminated configuration. In the present invention, since a specific phthalocyanine dye having excellent light resistance and coating properties is used as the recording layer, a recording layer having excellent light resistance can be easily obtained by coating. Also, the reflectance is improved. Further, by using the above-mentioned specific phthalocyanine-based dye, it exhibits a particularly high reflectance around 780 nm and is particularly useful for CD-WO type optical discs. Further, by recording on the information recording medium using a laser having a wavelength of about 780 nm, it is possible to obtain a signal having a high reflectance during reproduction and a high modulation factor (a pre-pit portion and a recording portion).

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an information recording medium of the present invention.

[Explanation of symbols]

 Reference Signs List 11 disc-shaped substrate 12 recording layer 13 reflective layer 14 protective layer 15 pregroove

Continuation of the front page (72) Inventor Yoshio Inagaki 210 Nakanuma, Minamiashigara-shi, Kanagawa Fujisha Shin Film Co., Ltd. (56) References JP-A-4-338590 (JP, A) JP-A-1-103494 (JP, A) JP-A-3-202395 (JP, A) JP-A-63-280083 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41M 5/26 G11B 7/24 516

Claims (2)

(57) [Claims] 1. A recording layer made of a dye capable of recording information by a laser and a reflective layer made of a metal are laminated in this order on a disk-shaped substrate provided with pregrooves and / or prepits on its surface. Wherein the dye is represented by the following general formula (I): M (Pc) _m (I) wherein M represents two hydrogen atoms, a metal, a metal oxide or a metal halide; Pc is represented by the following general formula (I
I): ｛Wherein W, X, Y and Z represent the 2-position of the benzene ring,
3-, 4-, or 5-substituents, each of which is a hydrogen atom or a general formula (IIIa) or (III
b): (However, in the general formula (IIIa), R ¹ is a hydrogen atom,
A represents an aliphatic group, an acyl group or a sulfonyl group, A represents a divalent aliphatic group, and R ² represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, an alkyl group, an acylamino group, and a sulfonylamino group. , Acyl group,
Represents an alkoxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an aryl group, an alkylsulfonyl group, a sulfonyl group, a heterocyclic group, an alkylthio group or an arylthio group, n ¹ represents an integer of 0 to 5, n ¹ is 2 In the above, R ² adjacently bonded on the benzene ring may be bonded to each other to form a 5- or 6-membered ring, and B represents an oxygen atom or a sulfur atom, and has the general formula (IIIb in), R ³ represents a hydrogen atom, an alkyl group, an acyl group or a sulfonyl group, R ⁴
Represents a halogen atom, an alkoxy group, an aryloxy group, an amino group, an alkylthio group or an arylthio group;
⁵ is hydrogen atom, halogen atom, alkyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, alkoxy group, aryloxy group, heterocyclic oxy group, acylamino group, anilino group, amino group, ureido group, sulfa Moiruamino group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfonamido group, a carbamoyl group, an acyl group, a sulfamoyl group, a sulfonyl group or an alkoxycarbonyl group, n ² represents an integer of 1 to 5, n ³ Represents an integer of 0 to 4, and substituents bonded adjacently on the benzene ring may be bonded to each other to form a 5- or 6-membered ring; , X, Y and Z are at least one of the above formulas (IIIa) and (IIIb). Represents on and m represents 1 or 2. An information recording medium characterized by being a phthalocyanine dye represented by the following formula: 2. On a disc-shaped substrate provided with pregrooves and / or prepits on its surface, the following general formula (I): M (Pc) _m (I) wherein M is two hydrogen atoms , A metal, a metal oxide or a metal halide, and Pc is represented by the following general formula (I
I): ｛Wherein W, X, Y and Z represent the 2-position of the benzene ring,
3-, 4-, or 5-substituents, each of which is a hydrogen atom or a general formula (IIIa) or (III
b): (However, in the general formula (IIIa), R ¹ is a hydrogen atom,
A represents an aliphatic group, an acyl group or a sulfonyl group, A represents a divalent aliphatic group, and R ² represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, a hydroxyl group, an alkyl group, an acylamino group, and a sulfonylamino group. , Acyl group,
Represents an alkoxy group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an aryl group, an alkylsulfonyl group, a sulfonyl group, a heterocyclic group, an alkylthio group or an arylthio group, n ¹ represents an integer of 0 to 5, n ¹ is 2 In the above, R ² adjacently bonded on the benzene ring may be bonded to each other to form a 5- or 6-membered ring, and B represents an oxygen atom or a sulfur atom, and has the general formula (IIIb in), R ³ represents a hydrogen atom, an alkyl group, an acyl group or a sulfonyl group, R ⁴
Represents a halogen atom, an alkoxy group, an aryloxy group, an amino group, an alkylthio group or an arylthio group;
⁵ is hydrogen atom, halogen atom, alkyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, alkoxy group, aryloxy group, heterocyclic oxy group, acylamino group, anilino group, amino group, ureido group, sulfa Moiruamino group, an alkylthio group, an arylthio group, a heterocyclic thio group, a sulfonamido group, a carbamoyl group, an acyl group, a sulfamoyl group, a sulfonyl group or an alkoxycarbonyl group, n ² represents an integer of 1 to 5, n ³ Represents an integer of 0 to 4, and substituents bonded adjacently on the benzene ring may be bonded to each other to form a 5- or 6-membered ring; , X, Y and Z are at least one of the above formulas (IIIa) or (IIIb). Stands for ion and m
Represents 1 or 2. An information recording medium, in which a recording layer made of a dye represented by the following formula and a reflective layer made of metal are laminated in this order, is irradiated with a laser having an oscillation wavelength in the range of 770 to 790 nm from the substrate side to record information. Optical information recording method comprising: