JPH10250231A - Optical recording medium and optical recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain superior optical recording characteristics and storage stability by providing a recording layer containing a metallic complex pigment having a specific coloring element as a ligand. SOLUTION: The metallic complex pigment has as a ligand a coloring element indicated by a formula I (in the formula, X1 shows a hydrogen atom or univalent organic group, Y1 indicates a heterocyclic group having a nitrogen atom adjacent to the substitution position, and Z1 denotes an aromatic group or heterocyclic group. Also, the metallic complex coloring element having a coloring element shown by the formula I as a ligand is available to be one shown by a formula II (in the formula, M1 indicates metallic ion, A1 shown an anion, m1 is 1 or 2, n1 is 0.1, or 2. The metal of the metallic complex coloring element is at least one kind of metal selected from Ni, Cu, Co, Zn, Cr, Pt, Pd or Fe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical recording medium having a recording layer of a dye thin film containing a metal complex dye and an optical recording method.

[0002]

2. Description of the Related Art In recent years, with the rapid increase in the amount of information, large-capacity optical recording media have been spotlighted. Optical recording media include:
There is a medium in which a dye thin film containing a dye as a main component is recordable as a recording layer.

[0003] For example, Optical Data Sto
Rage 1989 Technical Diges
t Series Vol. As described in 145 (1989) and the like, an optical recording medium such as an optical disk which is recordable by providing a recording layer containing a dye, a reflective film, and a protective film on a substrate has been proposed. This medium complies with the compact disk (CD) standard, and can be recorded by a 780 nm semiconductor laser, and can be reproduced by a commercially available CD player or CD-ROM player. Recently, development of an optical recording medium capable of performing higher-density recording / reproducing using a semiconductor laser of 620 nm to 680 nm has been studied.

An organic optical recording medium capable of recording information easily and at a high density with an inexpensive semiconductor laser uses a long-wavelength absorbing dye that absorbs light in the red to near-infrared region.

Conventionally, among various dyes, cyanine dyes having excellent absorption and reflection characteristics have been used for this purpose.
Due to low storage stability such as light fastness, there is a drawback that information is lost with time and writing becomes impossible.

To solve such a problem, for example, US Pat. Nos. 3,432,300 and 4,050,938.
No., JP-A-60-118748 and JP-A-63-19924
No. 8, JP-A-2-300288, etc., describe a light stabilizer or a light stabilization method, but have not yet achieved sufficient storage stability and have poor solubility in a coating solvent. Improvement is desired. Further, Japanese Patent Application Laid-Open
-44786, JP-A-2-76884, 5-17
No. 701 describes a metal complex dye having excellent storage stability, but cannot be used for applications such as optical recording media because the absorption wavelength is too long.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to use a dye having excellent solubility in a coating solvent, a high molar extinction coefficient, and excellent light fastness to provide excellent optical recording characteristics and storage stability. To provide an optical recording medium and an optical recording method.

[0008]

The above object of the present invention is attained by the following constitutions.

1. An optical recording medium comprising a recording layer containing a metal complex dye having a dye represented by the following general formula (1) as a ligand.

[0010]

Embedded image

In the formula, X ₁ represents a hydrogen atom or a monovalent organic group, Y ₁ represents a heterocyclic group having a nitrogen atom adjacent to the substitution position, and Z ₁ represents an aromatic group or a heterocyclic group. Represent.

2. 2. The optical recording medium according to item 1, wherein the metal complex dye having the dye represented by the general formula (1) as a ligand is represented by the following general formula (2).

[0013]

Embedded image

In the formula, M ₁ represents a metal ion, X ₁ represents a hydrogen atom or a monovalent organic group, Y ₁ represents a heterocyclic group having a nitrogen atom adjacent to the substitution position, and Z ₁ represents Represents an aromatic group or a heterocyclic group. A ₁ represents an anion, and m ₁ is 1
Or 2 and n ₁ represents 0, 1 or 2.

3. When the metal of the metal complex dye is Ni, Cu,
3. The optical recording medium according to 1 or 2, wherein the optical recording medium is at least one metal selected from Co, Zn, Cr, Pt, Pd, and Fe.

4. It has a recording layer containing a metal complex dye having a dye represented by the general formula (1) as a ligand and a metal complex dye having a dye represented by the following general formula (3) as a ligand. An optical recording medium characterized by the above-mentioned.

[0017]

Embedded image

In the formula, X ₂ represents a hydrogen atom or a monovalent organic group, Y ₂ represents an aromatic group, and Z ₂ represents an aromatic group or a heterocyclic group.

5. 5. The optical recording medium according to 4, wherein the metal complex dye having the dye represented by the general formula (3) as a ligand is represented by the following general formula (4).

[0020]

Embedded image

Where M_TwoRepresents a metal ion; X_TwoIs hydrogen
Represents an atom or a monovalent organic group; _TwoRepresents an aromatic group
Then Z_TwoRepresents an aromatic group or a heterocyclic group. A_TwoIs a shadow
And m_TwoRepresents 1 or 2, and n_TwoIs 0, 1 or
2 is represented.

6. An optical recording medium comprising a recording layer containing a metal complex dye having a dye represented by the general formula (1) as a ligand and a cyanine dye represented by the following general formula (5). .

[0023]

Embedded image

In the formula, B ₁ and B ₂ represent a heterocyclic ring, which may be the same or different. L ₁ , L ₂ , L ₃ , L ₄ and L ₅ represent a methine group, and may combine with each other to form a ring;
It may combine with B ₁ or B ₂ to form a ring. A ₃ represents an anion, p ₁ represents 0 or 1, and p ₂ represents 0, 1 or 2.

[7] At least one selected from the dyes represented by the general formula (1) and / or the general formula (3)
An optical recording medium having a recording layer containing two or more kinds of metal complex dyes comprising a kind of dye and a metal ion compound.

8. 8. An optical recording method, comprising: performing recording and reproduction on the optical recording medium according to any one of 1 to 7 using a semiconductor laser of 600 to 800 nm.

Hereinafter, the present invention will be described in more detail.

The dyes represented by the general formulas (1) to (5) will be described.

The general formula (1), as X ₁ and the general formula (3), the monovalent organic group represented by X ₂ in the general formula (4) of the general formula (2), for example, a halogen atom (e.g., fluorine Atom, chlorine atom, etc.), alkyl group (eg, methyl, ethyl, butyl, pentyl, 2-methoxyethyl, trifluoromethyl, 2-ethylhexyl, etc.), aryl group (eg, phenyl, 4-tolyl, 3-tolyl) , 4-methoxyphenyl, naphthyl, etc.), an acyl group (eg, acetyl, propionyl, benzoyl, etc.), an alkoxy group (eg, methoxy, ethoxy, butoxy, etc.), an alkoxycarbonyl group (eg, methoxycarbonyl, i- Groups such as propoxycarbonyl), acyloxy groups (eg, groups such as acetyloxy and ethylcarbonyloxy), carbamoyl Groups (eg, methylcarbamoyl, ethylcarbamoyl, butylcarbamoyl, phenylcarbamoyl, etc.), sulfamoyl groups (eg, sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, phenylsulfamoyl, etc.), alkylthio groups (eg, Methylthio, ethylthio, octylthio, etc.), arylthio groups (eg, phenylthio, 4-tolylthio, etc.), amino groups (eg, amino, methylamino, diethylamino, methoxyethylamino, etc.), acylamino groups (eg, Acetylamino, chloroacetylamino, propionylamino, benzoylamino, trifluoroacetylamino, etc.), alkylureido groups (eg, methylureido, ethylureido, methoxyethylureido, dimethyl Each group) such raid arylureido group (e.g., phenyl ureido group), an alkylsulfonamido group (e.g., methanesulfonamido, ethanesulfonamide, butane sulfonamide, trifluoromethyl sulfonamide,
Groups such as 2,2,2-trifluoroethylsulfonamide), arylsulfonamide groups (such as phenylsulfonamide and tolylsulfonamide), and alkylaminosulfonylamino groups (such as methylaminosulfonylamino and ethylamino) Groups such as sulfonylamino), arylaminosulfonylamino group (eg, phenylaminosulfonylamino group), and heterocyclic group (eg, groups such as pyridyl, pyrazyl, pyrazolyl, imidazolyl, furyl, thienyl, thiazolyl, oxazolyl). Can be

Preferred are an aryl group and a heterocyclic group, and specifically, a phenyl group, a 3-tolyl group, a 3,4-
Xylyl group, 4-methoxyphenyl group, 2-pyridyl group, 2-pyrazyl group, 3,5-dimethylpyrazolyl group,
4-ethyl-3,5-dimethylpyrazolyl group, 3,4
5-trimethylpyrazolyl group, 5-isopropyl-3-
Examples thereof include a methylpyrazolyl group and a 5-methyl-3-phenylpyrazolyl group.

The heterocyclic group represented by Y ₁ in the general formulas (1) and (2) is preferably a nitrogen-containing heterocyclic group having a nitrogen atom adjacent to the bonding position, for example, a 2-pyridyl group , A 2-pyrazyl group, a 2-thiazolyl group, a 2-thiazolidyl group, a 2-pyrrolyl group, a 2-imidazolyl group, and a 2-oxazolyl group.

The general formula (1), Z ₁ and of the general formula (2) (3), the aromatic group represented by Z ₂ in the general formula (4) an aryl group (eg phenyl group, a naphthyl group etc)
And examples of the heterocyclic group include a pyridyl group, a thienyl group, and a thiazolyl group. These aromatic groups and heterocyclic groups preferably have a hydroxy group, an alkoxy group, an aryloxy group, an amino group, or a substituted amino group as a substituent, and specifically, 4-hydroxyphenyl group, 4-methoxyphenyl Group, 3,4-dimethoxyphenyl group, 3,4,5-trimethoxyphenyl group, 3,4
-Methylenedioxyphenyl group, 4- (N-methylamino) phenyl group, 4- (N, N-dimethylamino) phenyl group, 4- (N, N-diethylamino) phenyl group,
4- (N, N-diethylamino) -2-methylphenyl group, 4- (N, N-diethylamino) -2-methoxyphenyl group, 4- (N-ethyl-N-2-methoxyethylamino) -2- Methylphenyl group, 4- (N-ethyl-
N-2-methanesulfonamidoethylamino) -2-methylphenyl group, 4- (N-ethyl-N-2-hydroxyethylamino) -2-methylphenyl group, 4- (N,
N-diethylamino) -2-acetamidophenyl group,
4- (N-ethyl-N-2-((2-methoxy) ethoxy) ethylamino) -2-methylphenyl group, 4-
(N, N-diethylamino) -2-methyl-5-methoxyphenyl group, 4- (N, N-diethylamino) -2-
Chlorophenyl group, 4- (N, N-diethylamino)-
2,5-dimethoxyphenyl group, 4- (N-ethyl-N
-Butyl) -2-methylphenyl group, 4- (N-anilino-N-ethyl) -2-methylphenyl group, 4-anilinophenyl group, julolidyl group and the like.

The general formula (3), the aromatic group represented by Y ₂ in the general formula (4) an aryl group (eg phenyl group, a naphthyl group, etc.), with the X _1, the X ₂ monovalent May have, as a substituent, the group mentioned as the organic group. For example, a halogen atom (eg, a fluorine atom, a chlorine atom, etc.), an alkyl group (eg, each group such as methyl, ethyl, butyl, 2-methoxyethyl, trifluoromethyl, etc.), an aryl group (eg, phenyl, 3-tolyl, etc.), acyl Groups (eg, acetyl, benzoyl, etc.), alkoxy groups (eg, methoxy, ethoxy, butoxy, etc.), alkoxycarbonyl groups (eg, methoxycarbonyl, etc.), acyloxy groups (eg, acetyloxy, etc.), A carbamoyl group (for example, each group such as methylcarbamoyl, ethylcarbamoyl, butylcarbamoyl, and phenylcarbamoyl), a sulfamoyl group (for example, a group such as sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, and phenylsulfamoyl), and an amino group (for example, Amino, methylami , Diethylamino, methoxyethylamino, etc.), acylamino group (eg, acetylamino, trifluoroacetylamino, propionylamino, etc.), alkylsulfonamide group (eg, methanesulfonamide, ethanesulfonamide, butanesulfonamide, Trifluoromethylsulfonamide, 2,2,2-
Groups such as trifluoroethylsulfonamide), arylsulfonamide groups (eg, phenylsulfonamide,
Each group such as tolylsulfonamide), an alkylaminosulfonylamino group (eg, each group such as methylaminosulfonylamino, ethylaminosulfonylamino), an arylaminosulfonylamino group (eg, a group such as phenylaminosulfonylamino), a cyano group, Examples include a hydroxy group and a heterocyclic group (for example, pyridyl, pyrazyl, pyrazolyl, imidazolyl, furyl, thienyl, thiazolyl, oxazolyl, etc.).

In the general formulas (2) and (4), M
_{As the} metal ions (metal ions forming a metal complex) represented by ₁ and M ₂ , 1 belonging to Groups I to VIII of the periodic table.
And multivalent metal ions. For example, Al, C
o, Cr, Cu, Fe, Mg, Mn, Mo, Ni, S
Preference is given to ions of metals such as n, Ti, Pt, Pd, Zr and Zn, especially Ni, Cu, Cr, Co, Zn and F.
The metal ion of e is preferred.

In the general formulas (2) and (4), A
_1, as the anion represented by A _2, for example enolate (acetylacetonate, hexafluoroacetylacetonate), halogen ions (fluoride, chloride, bromide, etc. iodide), hydroxide ions, sulfite ions, sulfate ions, Alkyl sulfonate ion,
Arylsulfonate ion, nitrate ion, nitrite ion, carbonate ion, perchlorate ion, alkylcarboxylic acid ion, aryl carboxylate ion, tetraalkyl borate, Sarishineto, benzoate, PF ₆ ^-, B
F ₄ ⁻ , SbF ₆ ^{− and the} like.

In the general formula (5), the heterocycles represented by B ₁ and B ₂ may be the same or different and include, for example, oxazole ring, imidazole ring, thiazole ring, pyrrole ring, indole Ring, benzoxazole ring, benzimidazole ring, benzothiazole ring, quinoline ring, pyridine ring and the like.

These rings may further form a condensed ring with another carbon ring (for example, a benzene ring) or a heterocyclic ring (for example, a pyridine ring). As a substituent on the ring, an alkyl group, an aryl group, a heterocyclic group, an acyl group, an amino group, a nitro group,
Examples thereof include a cyano group, an acylamino group, an alkoxy group, a hydroxy group, an alkoxycarbonyl group, and a halogen atom, and these groups may be further substituted. In particular, as the ring skeleton, indole ring, indolenine ring, 4,5-
Benzoindole ring, 4,5-benzoindolenine ring,
A 5,6-benzoindole ring, a 5,6-benzoindolenine ring, a 6,7-benzoindole ring, and a 6,7-benzoindolenine ring are preferred from the viewpoint of solubility.

In the general formula (5), the methine groups represented by L _{1 to} L ₅ may be unsubstituted or have a substituent. Examples of the substituent include an alkyl group and an aryl group. , A heterocyclic group, an acyl group, an amino group, an acylamino group, an alkoxy group, a hydroxy group, an alkoxycarbonyl group, a halogen atom and the like. Further, a part of L _{1 to} L ₅ may be combined with a substituent to form a cyclohexene ring, a cyclopentene ring, or the like.

In the general formula (5), the anion represented by A ₃ represents a counter ion necessary for neutralizing the charge,
For example, halogen ions (fluoride, chloride, bromide, iodide, etc.), hydroxide ions, sulfate ions, alkyl sulfonate ions, aryl sulfonate ions, carbonate ions, perchlorate ions, alkyl carboxylate ions, aryl carboxylate ions, tetracarboxylic acids Examples thereof include alkyl borate, PF ₆ ⁻ , BF ₄ ⁻ , SbF ₆ ⁻ , and metal dityl derivative.

The following are specific examples of the dye and metal complex dye of the present invention, but the present invention is not limited thereto.

Illustrative dye of the general formula (1) (Imidazole nuclear dye)

[0042]

Embedded image

[0043]

Embedded image

Illustrative metal complex dye of general formula (2)

[0045]

Embedded image

[0046]

Embedded image

Illustrative dye of the general formula (3) (Imidazole nuclear dye)

[0048]

Embedded image

[0049]

Embedded image

Illustrative metal complex dye of general formula (4)

[0051]

Embedded image

[0052]

Embedded image

Illustrative dye of general formula (5) (cyanine dye)

[0054]

Embedded image

The metal complex dye used in the recording layer of the present invention is
The metal complex dye is isolated by chelating the dye with the metal ion compound, and can be used by dissolving it in the recording layer coating solution. Alternatively, a dye and a metal ion compound may be added to and dissolved in the recording layer coating solution, and the resulting solution may be used as a metal complex dye in the coating solution.

Further, the metal complex dye of the present invention may be used alone, or a mixture of two or more metal complex dyes may be used.

Examples of the metal of the metal complex dye include monovalent and polyvalent monovalent metals belonging to Groups I to VIII of the periodic table similar to M ₁ and M ₂ in the aforementioned general formulas (1) and (2). Metal and the like. Specifically, Al, Co, Cr, Cu, F
e, Mg, Mn, Mo, Ni, Sn, Ti, Pt, P
d, Zr and Zn. Preferably Ni,
It is each metal of Cu, Co, Zn, Cr, Pt, Pd, and Fe, and particularly preferably is each metal of Ni, Cu, Co, Zn, and Fe.

Examples of the metal ion compound include various inorganic and organic anions and metal complexes.

Examples of anions include enolate (acetylacetonate, hexafluoroacetylacetonate, 3-methoxycarbonylacetylacetonate, etc.), halogen ion (fluorine ion, chlorine ion, bromine ion, iodine ion), hydroxyl ion , Sulfite ion,
Sulfate ion, nitrate ion, nitrite ion, carbonate ion,
Perchlorate ion, hexafluorophosphate ion, tetrafluoroboron ion, hexafluoroantimony ion, alkyl or aryl carboxylate ion (acetate ion, benzoate ion, salicylate ion, etc.), alkyl or aryl sulfonate ion (methanesulfonic acid ion) Ion, benzenesulfonic acid ion, p-toluenesulfonic acid ion, etc.), tetraalkylboron ion (tetrabutylboron ion, etc.), tetraarylboron ion (tetraphenylboron ion, etc.) and the like.

As the metal of the metal complex, the above-mentioned metals,
That is, monovalent and polyvalent metals belonging to Groups I to VIII of the periodic table similar to M ₁ and M ₂ in the general formulas (1) and (2) are exemplified. Specifically, Al, Co, Cr,
Cu, Fe, Mg, Mn, Mo, Ni, Sn, Ti, P
t, Pd, Zr, Zn and the like. Preferred are metals of Ni, Cu, Co, Zn, Cr, Pt, Pd, and Fe, and particularly preferred are Ni, Cu, Co, Zn,
Fe is each metal.

The dye represented by the general formula (1) of the present invention is
It may be used in combination with other dyes such as azo dyes, methine dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, and indoaniline dyes. When two or more dyes are used in combination, they can be used in combination with dyes having different spectral characteristics in the dye film. For example, a dye having a high laser light absorption rate may be used for recording, and a dye having a high laser light reflectance may be used for reproduction.

A semiconductor laser of 620 nm to 690 nm applied to a higher-density optical recording medium may be used in combination with a dye by selecting spectral characteristics so that recording and / or reproduction can be performed.

As the dye used in combination, an azomethine dye represented by the above formula (3) or a cyanine dye represented by the above formula (5) is preferable. These dyes are advantageous in that the spectral characteristics can be easily changed and the solubility of the coating solution is not deteriorated when mixed.

Further, when at least two kinds of dyes are used in combination in the recording layer, they may be arbitrarily selected from the dyes represented by the general formulas (1) and / or (3). Can be. Preferred are metal complex dyes represented by the general formula (2) and / or the general formula (4).

In use, at least two kinds of metal complex dyes may be isolated and mixed into a coating solution, or at least two kinds of dyes and a metal ion compound may be added to a coating solution and mixed. You may. These dyes have excellent coating solution solubility, can be applied to a desired concentration, and can be applied as a thin film.

The metal complex dye of the present invention can be made into a polymer by introducing a polymerizable substituent, if necessary, besides, an LB film is formed by introducing an oil-soluble group or a hydrophilic group, and oil is used. It can be processed into various forms such as dispersion or microcapsules.

The storage stability can be further improved by adding various storage stability improvers to the metal complex dye of the present invention. For example, ultraviolet absorbers such as benzotriazolylphenol derivatives, β-carotene, tocopherol derivatives, hydroquinone derivatives, spiroindane derivatives, phenol derivatives, amine derivatives, thioether derivatives, Ni dithiol derivatives, Ni phenanthroline derivatives, Ni benzylidene aniline derivatives And the like, and an antioxidant and a light stabilizer, and may be added alone or as a mixture of two or more.

Hereinafter, an optical recording medium using the metal complex dye of the present invention will be described.

As the substrate constituting the optical recording medium of the present invention, the wavelength range of laser light used for recording / reproduction (600 to
At 900 nm) (substantially 80% or more).

When the substrate is used as a normal compact disk, the substrate usually has a thickness of 1.2 mm and a diameter of 80 to 120 mm.

Examples of the material constituting the substrate include transparent resins such as polymethyl methacrylate resin, acrylic resin, polycarbonate resin, epoxy resin, polysulfone resin, and methylpentene polymer, and glass.

On the outer surface, inner surface, and inner / outer peripheral surface of the substrate,
If necessary, an oxygen barrier coating may be formed.
Further, it is preferable that a groove for tracking is formed on the substrate on which the recording layer is formed.

The optical recording medium having a recording layer containing the metal complex dye of the present invention has both light absorption suitable for recording and reflectance suitable for reproduction. The extinction coefficient k is preferably 0.01 to 0.1.

On the other hand, the refractive index n (the real part of the complex refractive index) of the recording layer in the wavelength region of the laser beam is 1.8 to 4.0.
It is preferred that

The recording layer of the optical recording medium of the present invention may contain various resins, surfactants, antistatic agents, dispersants, antioxidants, crosslinking agents, and the like.

The recording layer may be formed on one surface of the substrate, or may be formed on both surfaces of the substrate.
The thickness of the recording layer is preferably from 500 to 3000 angstroms.

The method for forming the recording layer on the substrate is not particularly limited, and examples thereof include spin coating, dip coating, spray coating, blade coating, roller coating, bead coating, and Mayer. Coating method,
Various methods such as a curtain coating method can be applied. Examples of the solvent used for forming the recording layer include ketone solvents such as cyclohexanone, ester solvents such as butyl acetate, ether solvents such as ethyl cellosolve, alcohol solvents such as diacetone alcohol and fluorinated alcohol, and toluene. Aromatic solvents such as
Examples thereof include an alkyl halide solvent.
It is preferable to provide a reflective layer on the recording layer.

As the reflection layer, for example, Au, Al--Mg
An alloy, an Al—Ni alloy, Ag, Pt, Cu, or other high-reflectivity metal can be used and formed by means such as vapor deposition or sputtering. Preferably, the thickness of the reflective layer is at least 500 angstroms.

On the reflective layer, a protective film made of, for example, an ultraviolet curable resin may be formed. The thickness of the protective film is usually 0.1 to 100 μm, and its hardness is 25.
The pencil hardness at C is preferably H to 8H.

An adhesive layer may be provided between the recording layer and the reflective layer to make them adhere to each other. It is desirable that the thickness of the adhesive layer be 10 to 300 Å.

As a light source for recording and reproducing information on and from the optical recording medium of the present invention, a solid-state laser, a gas laser, a dye laser and a semiconductor laser can be considered. From the viewpoint, a semiconductor laser is preferable. Since the compound of the present invention has particularly high recording sensitivity, a semiconductor laser having a wavelength of 600 to 800 nm is suitable. Preferably, it is suitable for recording and reproduction using a semiconductor laser of around 780 nm. On the other hand, the spectral characteristics of the metal complex dye were changed to 635 nm
Or an optical recording material suitable for a semiconductor laser of 650 nm.

[0082]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 Dye (1) -3 of the present invention and metal complex dye (2)-
The synthesis example of No. 3 is shown.

[0084]

Embedded image

13 g of 2-acetylthiazole (a) was placed in 70 ml of methanol, and 16 g of bromine was added dropwise at 20 ° C., followed by stirring for 30 minutes. Add water 2 to this reaction solution.
After adding 0 ml and leaving the mixture to stand for 15 minutes, the mixture was poured into 100 ml of a 5% aqueous sodium carbonate solution and allowed to stand. The product was precipitated by ice cooling, decanted, and the aqueous layer was discarded. The residue was dissolved in ethyl acetate, washed with water and dried over anhydrous sodium sulfate, and the ethyl acetate was distilled off to obtain 18.5 g of 2-bromoacetylthiazole (b).

16.5 g of (b) was added to 100 ml of ethyl acetate in which 38 g of amidinobenzene (c) was dissolved, and the mixture was stirred at room temperature for 7 hours. 7 ml of acetic acid was added to the reaction solution, and ethyl acetate was distilled off. After washing the residue with water and drying,
Purification by column chromatography gave 2-phenyl-4-thiazolylimidazole (d): 12 g.

(D): 11 g in 250 ml of methanol
And 4- (N, N-diethylamino) -2-methylaniline hydrochloride (e): 15 g, and further dissolved by adding 45 ml of triethylamine, followed by cooling with ice water. An aqueous solution 8 of 27 g of ammonium persulfate was dissolved in this solution while stirring.
0 ml was added dropwise at 15 ° C. over 60 minutes. The precipitated dye was filtered, washed with water, dried, and recrystallized from methanol to obtain dye (1) -3: 10 g. The structure was confirmed by an nmr spectrum and a mass spectrum.

Dye (1) -3 in 70 ml of methanol:
4 g was added and dissolved, and 1.7 g of nickel hexafluorophosphate was added, followed by stirring at room temperature. The precipitated metallic luster crystals were collected by filtration, washed with methanol, and dried to obtain 2.5 g of metal complex dye (2) -3.

Example 2 Table 1 shows the spectral absorption characteristics in acetone of the metal complex dye of the present invention and a dye not forming a metal complex as a comparison.

[0090]

[Table 1]

As is evident from the results in Table 1, the metal complex dye of the present invention has a high molar extinction coefficient, and is an advantageous dye for the recording layer.

Example 3 A dye thin film was prepared according to the following procedure, and the maximum absorption and light resistance were evaluated.

(1) Preparation of Dye Thin Film (Recording Layer) 1 g each of the metal complex dye of the present invention (described in Table 2) and comparative dyes (A) and (B) were weighed and dissolved in 50 ml of fluorinated alcohol. . The solubility was good. Apply the coating solution
Glass substrate (1.2m thick) by spin coating
m, diameter 80 mm) and dried at 80 ° C. for 30 minutes to form a recording layer having a thickness of about 1000 ° on the glass substrate.

(2) Light fastness test Using a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.), the recording layer of each sample was irradiated with xenon light, and the dye remaining rate after irradiation was measured. Here, as the irradiation conditions, the illuminance on the recording layer surface is 70,000 lux, and the temperature at the time of irradiation is 4
3 ° C. and the irradiation time was 30 hours. The dye residual ratio was determined from the following equation by measuring the light transmittance at the maximum absorption wavelength of the dye before and after irradiation with xenon light.

Dye residual rate = (100−T) / (100−T ₀ ) [where T ₀ is the transmittance before irradiation with xenon light and T is the transmittance after irradiation with xenon light] The results are shown in Table 2.

[0096]

[Table 2]

[0097]

Embedded image

As is evident from the results in Table 2, Samples 1, 2 and 3, which are recording media using the metal complex dye of the present invention, have a higher dye remaining ratio and excellent light resistance than Comparative Sample 4. It can be seen that On the other hand, it can be seen that Sample 5 using a metal complex dye different from that of the present invention has an absorption maximum that is too long and is not suitable as an optical recording medium.

Example 4 An optical recording medium was prepared according to the following procedure, and its light resistance, optical recording characteristics, and the like were evaluated.

(Preparation of Optical Recording Medium) Using a metal complex dye (described in Table 3) of the present invention on a grooved polycarbonate resin substrate having a diameter of 120 mm and a thickness of 1.2 mm, a recording layer was prepared in the same manner as in Example 3. The reflective layer (thickness: 100 mm) made of Au is formed by sputtering, and a protective film (ultraviolet curable acrylic resin, thickness: 5 μm) is formed. Recording media 6 and 7 were prepared. For comparison, an optical recording medium 9 was similarly prepared using the comparative dye (B) for the recording layer.

Further, instead of the metal complex dye of the present invention,
The dye of the present invention (described in Table 3) and nickel acetylacetonate as a metal ion compound were added to the coating solution so as to be equivalent to the metal complex dye to prepare an optical recording medium of the present invention in the same manner as described above. 8 was produced. When the reflectance was measured, the optical recording media 6, 7, and 8 showed 70% or more. Information was recorded on these samples by changing the power with a 780 nm semiconductor laser, and reproduction was performed at 0.8 mW.

Using the xenon fade meter used in Example 3, a similar recording / reproducing experiment was performed after light irradiation at 70,000 lux for 30 hours. Table 3 shows the results.

[0103]

[Table 3]

As is clear from the results shown in Table 3, the optical recording media 6, 7, and 8 of the present invention could perform good recording / reproduction satisfying the CD standard. In addition, it was found that they had excellent light resistance and had stable recording and reproducing characteristics. On the other hand, in the comparative optical recording medium 9, the reflectance was reduced by the reproduction light of the laser, the reproduction failure occurred, and the phenomenon that the recording could not be performed even by the light irradiation by the xenon fade meter was observed.

Example 5 An optical recording medium was prepared using two or more dyes in combination according to the following procedure, and the light resistance, the optical recording characteristics and the like were evaluated.

(Preparation of Optical Recording Medium) The dye of the present invention (Table 4) was formed on a polycarbonate resin substrate in the same manner as in Example 4.
), A recording layer (1200 mm thick) is applied, and then a reflective layer (Au, 100 mm thick) and a protective film (ultraviolet curable acrylic resin, 5 μm thick) are formed. Optical recording media 10 to 17 were prepared. For comparison, an optical recording medium 18 was similarly prepared using the comparative dye (B) in combination with the recording layer.

Optical recording media 10 to 16 and 1 shown in Table 4
In the recording layer coating liquid of No. 8, the dye (A) shown in Table 4 (2 parts)
Dye (B), 8 parts, was used in combination. In the optical recording medium 17, the dye (A), 2 parts, the dye (B), 4 parts, and the dye (C), 4 parts were used together. The dye was added so that the number of moles of the dye contained in the recording layer coating solution of each sample was equal. Further, the optical recording materials 10, 11, 12 and 15 shown in Table 4
Was prepared by adding nickel hexafluoroacetylacetonate as a metal ion compound in an amount of 0.75 times the number of moles of the dye. When the reflectance was measured, the optical recording media 10 to 17 showed 70% or more. Information was recorded on these samples by changing the power with a 780 nm semiconductor laser, and reproduction was performed at 0.8 mW.

Using the xenon fade meter used in Example 3, a similar recording / reproducing experiment was performed after light irradiation at 70,000 lux for 30 hours. Table 4 shows the results.

[0109]

[Table 4]

As is clear from the results in Table 4, the optical recording media 10 to 17 of the present invention can be used in combination with a
It was clarified that good recording / reproducing that satisfies the standard could be performed, and that it had stable recording / reproducing characteristics with excellent light resistance. On the other hand, in the comparative optical recording medium 18, the reflectance was reduced by the reproduction light of the laser, the reproduction failure occurred, and the phenomenon that the recording could not be performed even by the light irradiation by the xenon fade meter was observed.

As is clear from the above, the optical recording medium using the metal complex dye according to the present invention has excellent optical recording characteristics and storage stability.

[0112]

The optical recording medium and the optical recording method according to the present invention have excellent solubility in a coating solvent, a high molar extinction coefficient,
In addition, by using a dye having excellent light resistance, an effect having excellent optical recording characteristics and storage stability can be obtained.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07D 401/14 231 C07D 401/14 231 403/04 231 403/04 231 233 233 417/04 233 417/04 233 417/14 231 417/14 231 C09B 55/00 C09B 55/00 DA G11B 7/24 516 G11B 7/24 516 (72) Inventor Mari Mari Konica, No. 1, Sakuracho, Hino-shi, Tokyo In-house (72) Inventor Okubo Kimihiko Konica Stock Company, 1 Sakuracho, Hino City, Tokyo

Claims (8)

[Claims] 1. An optical recording medium having a recording layer containing a metal complex dye having a dye represented by the following general formula (1) as a ligand. Embedded image Wherein, X ₁ is a hydrogen atom or a monovalent organic group, Y ₁
Represents a heterocyclic group having a nitrogen atom adjacent to the substitution position, and Z ₁ represents an aromatic group or a heterocyclic group. ] 2. The optical recording medium according to claim 1, wherein the metal complex dye having the dye represented by the general formula (1) as a ligand is represented by the following general formula (2). . Embedded image [Wherein, M ₁ represents a metal ion, X ₁ represents a hydrogen atom or a monovalent organic group, Y ₁ represents a heterocyclic group having a nitrogen atom adjacent to the substitution position, and Z ₁ represents an aromatic group. Represents a group or a heterocyclic group. A ₁ represents an anion, m ₁ represents 1 or 2, and n ₁ represents 0, 1 or 2. ] 3. The metal of the metal complex dye is Ni, Cu, C
3. The optical recording medium according to claim 1, wherein the optical recording medium is at least one metal selected from the group consisting of o, Zn, Cr, Pt, Pd, and Fe. 4. A metal complex dye having a dye represented by the general formula (1) as a ligand and a metal complex dye having a dye represented by the following general formula (3) as a ligand: An optical recording medium, comprising: a recording layer. Embedded image Wherein, X ₂ represents a hydrogen atom or a monovalent organic group, Y ₂
Represents an aromatic group, and Z ₂ represents an aromatic group or a heterocyclic group. ] 5. The optical recording medium according to claim 4, wherein the metal complex dye having the dye represented by the general formula (3) as a ligand is represented by the following general formula (4). Embedded image [Wherein, M ₂ represents a metal ion, X ₂ represents a hydrogen atom or a monovalent organic group, Y ₂ represents an aromatic group, and Z ₂ represents an aromatic group or a heterocyclic group. A ₂ represents an anion, and m ₂
Represents 1 or 2, and n ₂ represents 0, 1 or 2. ] 6. A recording layer comprising a metal complex dye having a dye represented by the general formula (1) as a ligand and a cyanine dye represented by the following general formula (5). Optical recording medium. Embedded image [Wherein B ₁ and B ₂ represent a heterocyclic ring, which may be the same or different. L ₁ , L ₂ , L ₃ , L ₄ and L ₅ represent a methine group and may be bonded to each other to form a ring, or may be bonded to B ₁ or B ₂ to form a ring. A ₃ represents an anion, p ₁ represents 0 or 1, and p ₂ represents 0, 1 or 2. ] 7. A metal complex dye comprising a metal ion compound and at least one dye selected from the dyes represented by the general formulas (1) and / or (3)
An optical recording medium having a recording layer containing at least one species. 8. An optical recording method comprising performing recording and reproduction on the optical recording medium according to claim 1 using a semiconductor laser of 600 to 800 nm.