JP2000043420A - Photo-recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance light-fastness and storage stability, and make use possible as CD-R in a present system, and also enable reproduction to be done in the high density optical disk of a following generation by containing at least one kind of a specific compound in a recording layer. SOLUTION: The photo-recording medium contains at least one kind of a compound expressed by formula (in the formula, R1-R4 show a hydrogen atom, a halogen atom, a nitro group, or the like, (a)-(d) show integers 0-4, X and Y are substitutional group consisting of a hydroxy group, a carboxyl group, or the like, M is a bivalent or trivalent metallic atom that can have oxygen, a halogen atom, or the like, (n) is an integer of 1 or 2, A and B are atomic groups needed for a heterocycle, R5 shows a hydrogen atom or univalent substitutional group. Also, the recording layer is made to have as principal component a mixture of one kind of the compound in the formula and organic coloring matter having a maximum absorptive wavelength in 680-700 nm. Thus, it results in a CD-R recording medium that can be reproduced only in a following generation system.

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 more particularly, to an information recording medium by irradiating a light beam.
The present invention relates to an optical recording medium on which an optical change such as a transmittance and a reflectance of a recording material is caused to record and reproduce information and to allow additional recording.

[0002]

2. Description of the Related Art At present, as a next-generation large-capacity optical disk, D
VD-R is under development. The elemental technologies for improving the recording capacity include recording material development for miniaturizing recording pits,
It is necessary to develop technology such as adoption of image compression technology represented by PEG2 and shortening of the wavelength of a semiconductor laser for reading recorded pits.

Hitherto, as a semiconductor laser in the red wavelength region, a 670 nm Al laser has been used for bar code readers and measuring instruments.
Although only GaInP laser diodes have been commercialized, red lasers are being used in the optical storage market in earnest as the density of optical disks increases. DVD
In the case of a drive, the light source is 635 nm band and 650 nm
It is standardized at two wavelengths of the laser diode in the band. For high-density recording, the wavelength is desirably shorter, and as a drive for write-once media, a wavelength of 635 nm is used.
Is preferred. On the other hand, a read-only DVD-ROM drive is commercialized at a wavelength of about 650 nm.

[0004] Under these circumstances, the most preferable DVD-
R media is a medium (DV) capable of recording and reproducing at a wavelength of about 635 nm and reproducing at a wavelength of about 650 nm.
D-R), a recording material which is excellent in light resistance and storage stability and can be recorded and reproduced by an optical pickup using a laser of 650 nm or less is desired. Recently, cyanine dyes and azo metal chelate dyes have been actively developed as recording materials. For DVD-R, for example, an imidazole-based azomethine dye + metal reflective layer is used as a recording material (Japanese Patent Laid-Open No. 8-198872). No. 8-209012,
JP-A-8-283263) and those using a cyanine dye / metal reflective layer as a recording material (PIONEER®).
& D vol. 6 No. 2: DVD-Recorda
ble, the basic development of DVD-R dye disks) and the like. However, cyanine dyes have excellent optical properties but extremely poor light fastness, and azo metal chelate dyes have good light fastness but have not been found to be satisfactory in optical properties. That is, at present, a recording material which is excellent in light resistance and storage stability and which can be recorded and reproduced by an optical pickup using a laser of 650 nm or less has not yet been developed.

[0005] The current CD-R disc system has an oscillation wavelength of 770 to 790 nm for a laser used, and is configured to be able to perform recording and reproduction. In this system, as in the above, it is essential to increase the capacity and shorten the recording and reproduction wavelengths. In current CDs and CD-ROMs, Al is coated on the unevenness of the substrate itself, and the wavelength dependence of the reflectance of Al is small, so that reproduction is possible even if the laser wavelength is shortened in the future. . However, the CD-R uses a dye having a maximum absorption wavelength at 680 nm to 750 nm for the recording layer, and has a 770 nm thickness due to its optical constant and film thickness.
Since the reflectivity is set so as to be as high as about 790 nm, the reflectivity is extremely low in a wavelength region of 700 nm or less, and it is impossible to cope with the shortening of the laser wavelength.
-Information recorded and reproduced by the R system cannot be reproduced by a future system.

[0006]

The present invention has a higher solubility in an organic solvent applicable to a high-density optical disk system using a semiconductor laser having an oscillation wavelength at a shorter wavelength than the conventional system, and has a high light resistance and storage. An object is to provide a recording material for an optical recording medium (DVD-R) having excellent stability.

[0007]

As a result of intensive studies, the present inventors have found a recording layer mainly composed of a counter ion compound of an azo metal chelate dye and a cyanine dye having a specific structure, and have obtained an oscillation wavelength of 700 nm. An optical recording medium which is applicable to a high-density optical disk system using the following semiconductor laser and has high light resistance has been achieved.

That is, according to the present invention, first, a recording layer is provided on a substrate directly or via an undercoat layer, and further, if necessary, a reflective layer, a protective layer or an adhesive layer, and a second substrate Wherein the recording layer contains at least one compound represented by the following general formula (I). General formula (I)

Embedded image [Wherein, R _{1 to} R ₅ , a to d, X, Y, M, n, A and B
Represents the following, respectively. R ₁ , R ₃ : hydrogen atom, halogen atom, nitro group, hydroxyl group, carboxy group, cyano group, sulfone group, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic ring Residue, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted Aryloxycarbonyl group, substituted or unsubstituted acyl group, substituted or unsubstituted acyloxy group or substituted or unsubstituted amino group, R ₂ , R ₄ : hydrogen atom, halogen atom, nitro group, hydroxyl group, carboxy group, Cyano group, sulfone group, substituted or unsubstituted alkyl group, substituted or unsubstituted Aryl group, substituted or unsubstituted heterocyclic residue, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted Substituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, substituted or unsubstituted acyloxy group or substituted or unsubstituted amino group, a, b, c, d: 0 to 0 An integer of 4, X, Y: a substituent comprising a hydroxy group, a carboxyl group, a sulfonic acid derivative, an amino group, M: a divalent or trivalent metal atom which may have oxygen, a halogen atom, etc., n: 1 Or an integer of 2, A, B: groups of atoms necessary to complete a heterocyclic ring, which may be the same or different, R ₅ : water An element atom or a monovalent substituent. Second, in the first optical recording medium, the recording layer contains at least one compound represented by the general formula (I) and a dye having a maximum absorption wavelength at 680 to 750 nm. An optical recording medium is provided.
Third, in the first or second optical recording medium, in the general formula (I), A is a compound represented by an indolenine ring and B is a compound represented by a benzindolenine ring. A medium is provided. Fourth, in the first or second optical recording medium, A and B in the general formula (I)
Is a compound represented by a benzindolenine ring. Fifth, in the first to fourth one of the optical recording medium, in the general formula (I), X and Y are O ^- or COO ^- optical recording medium which is a compound represented by Is provided. Sixth, in the second optical recording medium, 680-750n
An optical recording medium is provided, wherein the dye having the maximum absorption wavelength at m is at least one of a cyanine dye of pentamethine, a phthalocyanine dye, and an azo metal chelate compound. Seventh, in the second or sixth optical recording medium, the recording layer is recorded and reproduced by a first wavelength light of 630 to 690 nm and a second wavelength light of 770 to 830 nm. Is provided. Eighth, in the second or sixth optical recording medium, the recording layer is recorded by light having a wavelength of 770 to 830 nm, and light having a wavelength of 630 to 690 nm and
An optical recording medium characterized by being reproduced by light having a wavelength of 70 to 830 nm is provided.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
As an optical recording medium having a reflective layer on a substrate, a recordable CD (CD) conforming to the Compact Disc (CD) standard is used.
-R) has been commercialized. Wavelength 770-83 for recording layer
Information is recorded and reproduced by irradiating a laser beam of 0 nm and detecting reflected light that causes a physical or chemical change in the recording layer. Recently, semiconductor lasers having shorter wavelengths have been developed, and red semiconductor lasers having wavelengths of 630 to 680 nm have been put to practical use. By shortening the wavelength of the recording / reproducing laser, the beam diameter can be further reduced, and a high-density optical recording medium can be realized. The present invention provides wavelengths of 630-6.
The present invention relates to a high-density optical recording medium (DVD-R) using a recording material capable of recording and reproducing at 80 nm.

The optical recording medium of the present invention is characterized in that its recording layer contains at least one compound represented by the above general formula (I). In the general formula (I), R
₁ and R ₃ are a hydrogen atom, a halogen atom, a nitro group, a hydroxyl group, a carboxy group, a cyano group, a sulfone group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic residue. Group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted Represents an aryloxycarbonyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted acyloxy group, or a substituted or unsubstituted amino group.

R ₂ and R ₄ are hydrogen, halogen, nitro, hydroxyl, carboxy, cyano, sulfone, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted A heterocyclic residue,
Substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted aryloxy Represents a carbonyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted acyloxy group, or a substituted or unsubstituted amino group.

Specific examples of the halogen atom include fluorine, chlorine, bromine and iodine.

Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-octyl group. Primary alkyl groups such as nonyl group and n-decyl group; isobutyl group, isoamyl group, 2-methylbutyl group, 2-methylpentyl group, 3-methylpentyl group, 4
-Methylpentyl group, 2-ethylbutyl group, 2-methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 2-ethylpentyl group,
3-ethylpentyl group, 2-methylheptyl group, 3-methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 2-ethylhexyl group, 3-ethylhexyl group, isopropyl group, sec-butyl group, 1- Ethylpropyl group, 1-methylbutyl group, 1,2-dimethylpropyl group, 1-methylheptyl group, 1-ethylbutyl group,
1,3-dimethylbutyl group, 1,2-dimethylbutyl group, 1-ethyl-2-methylpropyl group, 1-methylhexyl group, 1-ethylheptyl group, 1-propylbutyl group, 1-isopropyl-2- Methylpropyl group, 1-ethyl-2-methylpropyl group, 1-ethyl-2-methylbutyl group, 1-propyl-2-methylpropyl group, 1-
Methylheptyl group, 1-ethylhexyl group, 1-propylpentyl group, 1-isopropylpentyl group, 1-isopropyl-2-methylbutyl group, 1-isopropyl-3
Secondary alkyl groups such as -methylbutyl group, 1-methyloctyl group, 1-ethylheptyl group, 1-propylhexyl group, 1-isobutyl-3-methylbutyl group; neopentyl group, tert-butyl group, tert-hexyl group, t
tertiary alkyl groups such as ert-amyl group and tert-octyl group; cyclohexyl group, 4-methylcyclohexyl group, 4-ethylcyclohexyl group, 4-tert-butylcyclohexyl group, 4- (2-ethylhexyl) cyclohexyl group, and bornyl And cycloalkyl groups such as an isobornyl group (adamantane group).

Further, these primary and secondary alkyl groups are
A hydroxyl group, a halogen atom, a nitro group, a carboxy group, a cyano group, a substituted or unsubstituted aryl group, may be substituted with a substituted or unsubstituted heterocyclic residue, etc.
The alkyl group may be substituted via an atom such as sulfur or nitrogen. Examples of the alkyl group substituted via oxygen include a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, a butoxyethyl group, an ethoxyethoxyethyl group, a phenoxyethyl group,
Methoxypropyl group, ethoxypropyl group, piperidino group, morpholino group, etc., as the alkyl group substituted through sulfur, methylthioethyl group, ethylthioethyl group, ethylthiopropyl group, phenylthioethyl group, etc. Examples of the alkyl group substituted via nitrogen include a dimethylaminoethyl group, a diethylaminoethyl group, and a diethylaminopropyl group.

Specific examples of the above aryl group include phenyl, pentalenyl, indenyl, naphthyl, azulenyl, heptalenyl, biphenylenyl, as
-Indacenyl group, s-indacenyl group, acenaphthalenyl group, fluorenyl group, phenalenyl group, phenanthranyl group, anthranyl group, fluoracenyl group, acephenanthrenyl group, aceanthrylene group, triphenylenyl group, pyrenyl group, chrysenyl group, naphthacenyl group And the like. Further, these aryl groups include a hydroxyl group,
It may be substituted with a halogen atom, a nitro group, a carboxy group, a cyano group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic residue, and the like, and via an atom such as oxygen, sulfur, or nitrogen. The alkyl group may be substituted.

Specific examples of the above heterocyclic residue include furyl, thienyl, pyrrolyl, 2H-pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, furazanyl, pyranyl and the like. Group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, pyrrolinyl group, pyrrolidinyl group, imidazolinyl group, pyrazolinyl group, pyrazolidinyl group, piperidyl group, pyrrelidino group, piperazinyl group, morpholinyl group, morpholino group, indolyl group, isoindolyl group, 1H-indazolyl group, 4H-chromenyl group, quinolyl group, isoquinolyl group, cinnolinyl group, quinazolinyl group, quinoxalinyl group, phthalazinyl group, prenyl group, pteridinyl group, xanthenyl group, carbazolyl group, Ntorijiniru group, acridinyl group, phenazinyl group, phenanthrolinyl group, indolinyl group, isoindolinyl group, etc. chromanyl group. Further, these heterocyclic residues may be substituted with a hydroxyl group, a halogen atom, a nitro group, a carboxy group, a cyano group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic residue, and the like. It may be substituted with the above-mentioned alkyl group via an atom such as oxygen, sulfur, or nitrogen. Further, these substituents may be such that a plurality of the same or different substituents are substituted on the ring.

Specific examples of the above-mentioned alkoxy group may be those in which a substituted or unsubstituted alkyl group is directly bonded to an oxygen atom, and specific examples of the alkyl group include the aforementioned specific examples. Specific examples of the above aryloxy group may be those in which a substituted or unsubstituted aryl group is directly bonded to an oxygen atom, and specific examples of the aryl group include the aforementioned specific examples.

Specific examples of the carbamoyl group include those in which a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group is directly and independently bonded to the nitrogen atom of the carbamoyl group. Of the above, specific examples of the alkyl group and the aryl group include the specific examples described above.

Specific examples of the above sulfonamide group include:
Each independently directly at the nitrogen atom of the sulfonamide group,
It is sufficient that a hydrogen atom or a substituted or unsubstituted alkyl group is bonded, and specific examples of the alkyl group include the specific examples described above.

Specific examples of the above-mentioned alkoxycarbonyl group may be those in which a substituted or unsubstituted alkyl group is directly bonded to the oxygen atom of the alkoxycarbonyl group. Specific examples of the alkyl group are those described above. Can be mentioned.

Specific examples of the aryloxycarbonyl group include those in which a substituted or unsubstituted aryl group is directly bonded to the oxygen atom of the aryloxycarbonyl group. Specific examples of the aryl group are those described above. Specific examples can be given.

Specific examples of the acyl group include those having a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group bonded directly to the carbonyl carbon atom of the acyl group. Specific examples of the group include the specific examples described above.

Specific examples of the acyloxy group include those in which a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group is directly bonded to the carbonyl carbon atom of the acyloxy group. Specific examples of the group include the specific examples described above.

Specific examples of the above amino group may be those in which a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group is directly bonded to a nitrogen atom. Specific examples of the alkyl group and the aryl group include Can be the above-mentioned specific examples.

X and Y each represent a substituent comprising a hydroxy group, a carboxyl group, a sulfonic acid derivative and an amino group, and M represents a divalent or trivalent metal atom which may have an oxygen atom, a halogen atom or the like. Represent. Specific examples of metal atoms include titanium, vanadium, chromium, manganese, iron, cobalt,
Nickel, copper, zirconium, niobium, molybdenum, technenium, ruthenium, rhodium, palladium and the like can be mentioned. a, b, c, and d are integers of 0, 1, 2, 3, and 4, and n represents an integer of 1 and 2.

A and B represent a group of atoms necessary to complete the heterocyclic ring, and may be the same or different. R ₅ represents a hydrogen atom or a monovalent substituent. Specific examples of A and B include a thiazole ring, a benzothiazole ring, an oxazole ring, a benzoxazole ring, an indolenine ring, a benzoindolenine ring, a dibenzoindolenine ring, a pyridine ring, a quinoline ring, and an imidazole ring. Indolenine rings and benzoindolenine rings are particularly preferred. The heterocyclic ring may be substituted by a halogen atom, an alkyl group, an aryl group, an acyl group, an amino group and the like. In view of optical characteristics, storage stability, and light resistance, an indolenine ring and a benzoindolenine ring are particularly preferable.

Specific examples of the compound represented by the general formula (I) include those shown in Tables 1 to 11.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

[Table 4]

[0032]

[Table 5]

[0033]

[Table 6]

[0034]

[Table 7]

[0035]

[Table 8]

[0036]

[Table 9]

[0037]

[Table 10]

[0038]

[Table 11]

As described above, the main component of the recording layer is a mixture of at least one compound represented by the general formula (I) and an organic dye having a maximum absorption wavelength at 680 to 750 nm. As a result, the CD-R recording medium can be recorded and reproduced by the current system and can be reproduced only by the next-generation system. In this case, as the dye having the maximum absorption wavelength at 680 to 750 nm, the dyes described in the publications described in the prior art can be used. In particular, pentamethine cyanine dyes, phthalocyanine dyes and azo metal chelate dyes are preferred.

Preferred examples of the cyanine dye of pentamethine include those represented by the following general formula (II).

Embedded image In the formula, R ³¹ and R ³² are an alkyl group having 1 to 3 carbon atoms, R ³³ ,
R ³⁴ is a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms;
Represents an acid anion. Note that the aromatic ring may be condensed with another aromatic ring, or may be substituted with an alkyl group, a halogen atom, an alkoxy group, or an acyl group.

Preferred examples of the phthalocyanine dye include those represented by the following formula (III) or (IV).

Embedded image In the formula, M ¹ is Ni, Pd, Cu, Zn, Co, Mn, F
e, TiO or VO. X ^{11 to} X ¹⁴ are each independently -OR, -SR or a hydrogen atom at the α-position of the substitution position, and not all of them are hydrogen atoms. R represents a substituted or unsubstituted linear or branched alkyl group having 3 to 12 carbon atoms, a cycloalkyl group, or a substituted or unsubstituted aryl group. Substituents on the benzene ring other than X ^{11 to} X ¹⁴ are a hydrogen atom or a halogen atom.

[0042]

Embedded imageWhere M^TwoRepresents Si, Ge, In, or Sn. X
^Fifteen~ X¹⁸Are each independently -OR at the substitution position α-, -S
R or a hydrogen atom, and all of them are hydrogen atoms
Absent. R represents a substituted or unsubstituted C 3-12 carbon atom.
Linear or branched alkyl, cycloalkyl or
Represents a substituted or unsubstituted aryl group. Y¹, Y^TwoIs
-OSiR^{twenty five}R²⁶R²⁷, -OCOR^{twenty five}R²⁶R²⁷, Or-
OPOR ^{twenty five}R²⁶R²⁷And R^{twenty five}~ R²⁷Is German
Stands for an alkyl group or an aryl group having 1 to 10 carbon atoms.
You. X⁹~ X¹²Other substituents on the benzene ring are hydrogen atoms
Or a halogen atom.

Preferred examples of the azo metal chelate dye include one or more azo metal chelate compounds of an azo compound represented by the following general formula (V) and a metal. Preferred examples of the metal Ni, Pt, P
d, Co, Cu, Zn and the like.

Embedded image In the formula, A represents a residue which forms a heterocyclic ring together with the carbon atom and the nitrogen atom to which it is bonded, and B represents an aromatic ring together with the two carbon atoms to which it is bonded. Or a residue forming a heterocyclic ring, and X represents a group having active hydrogen.

When the at least one dye represented by the general formula (I) and the at least one dye represented by the general formulas (II) to (V) of the present invention are used in combination, the weight composition ratio is as follows: Dye of the present invention / [dye of (II) to (V)] = 10/1
00 to 90/100, preferably 40/100 to 20 /
100. When both dyes are used in combination, the thickness of the recording layer is 500 to 5 μm, preferably 1000 to 50 μm.
00 °.

Next, the configuration of the recording medium of the present invention will be described. FIG. 1 is a diagram showing an example of a layer configuration applicable to the recording medium of the present invention, which is an example of a write-once optical disc. The recording layer 2 is provided on the substrate 1 via an undercoat layer 3 if necessary.
And, if necessary, a protective layer 4. Further, a hard coat layer 5 can be provided below the substrate 1 as needed. FIG. 2 is a diagram showing another example of a layer structure applicable to the recording medium of the present invention, which is an example of a CD-R medium. A reflective layer 6 is provided on the recording layer 2 having the configuration shown in FIG. FIG. 3 is a diagram showing an example of a layer structure of another type (for DVD-R) applicable to the recording medium of the present invention. In this case, in FIGS. 3A and 3B, the protective layer having the structure of FIG. 4, an adhesive layer 4 is provided, on which the substrate 1 is provided, and in (c), a hard coat layer 5 is further provided thereon. That is, the recording medium of the present invention may have an air sandwich structure in which the recording layer (organic thin film layer) having the structure shown in FIGS. Alternatively, a laminated structure in which the protective layers are bonded to each other may be employed.

Next, the required characteristics of the constituent layers and the constituent materials thereof will be described. 1) Substrate As a necessary characteristic of the substrate, when recording / reproducing is performed from the substrate side, it must be transparent to the laser beam to be used. However, when recording / reproducing is performed from the recording layer side, it is not necessary to be transparent. As the substrate material, for example, polyester, acrylic resin, polyamide, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, plastic such as polyimide, glass, ceramic, metal or the like can be used. Note that a guide groove or guide pit for tracking, and a preformat such as an address signal may be formed on the surface of the substrate.

2) Recording Layer The recording layer is capable of causing some optical change by irradiation with a laser beam and recording information by the change.
In this recording layer, at least one kind of the compound represented by the general formula (I), and in some cases, the compound represented by the general formula (II)
It is necessary that at least one of the dyes represented by (V) is contained. Further, these dyes can be used by mixing or laminating them with other organic dyes, metals, and metal compounds in order to improve optical characteristics, recording sensitivity, and signal characteristics. Other organic dyes in this case include polymethine dyes, naphthalocyanine-based, phthalocyanine-based, squarylium-based, croconium-based, pyrylium-based, naphthoquinone-based, anthraquinone (indanthrene) -based, xanthene-based, triphenylmethane-based, and azulene-based , A tetrahydrocholine-based, a phenanthrene-based, a triphenothiazine-based dye, and a metal complex compound. Examples of metals and metal compounds include In, Te, Bi,
Se, Sb, Ge, Sn, Al, Be, TeO ₂ , Sn
O, As, Cd and the like can be mentioned, and each of them can be used in the form of dispersion mixing or lamination. Further, various materials such as a polymer material, for example, an ionomer resin, a polyamide resin, a vinyl resin, a natural polymer, silicone, a liquid rubber, or a silane coupling agent may be dispersed and mixed in the dye, For the purpose of improvement, stabilizers (eg, transition metal complexes), dispersants, flame retardants, lubricants, antistatic agents, surfactants, plasticizers, and the like can be used together.

The recording layer is formed by vapor deposition, sputtering, C
It can be carried out by usual means such as VD or solvent application. When using the coating method, the above dye or the like is dissolved in an organic solvent, and spray, roller coating,
It can be performed by a conventional coating method such as dipping or spin coating. Examples of the organic solvent used include alcohols such as methanol, ethanol, and isopropanol; ketones such as acetone, methyl ethyl ketone and cyclohexanone; amides such as N, N-dimethylacetamide and N, N-dimethylformamide; and sulfoxides such as dimethyl sulfoxide. , Tetrahydrofuran, dioxane, diethyl ether, ethers such as ethylene glycol monomethyl ether, esters such as methyl acetate, ethyl acetate, chloroform, methylene chloride, dichloroethane, carbon tetrachloride, aliphatic halogenated carbons such as trichloroethane,
Aromatics such as benzene, xylene, monochlorobenzene and dichlorobenzene, or methoxyethanol;
Cellsolves such as ethoxyethanol, and hydrocarbons such as hexane, pentane, cyclohexane, and methylcyclohexane. The thickness of the recording layer is 100
Å-10 μm, preferably 200Å-2000Å is suitable.

3) Undercoat Layer The undercoat layer is used to improve the adhesiveness, barrier against water or gas, improve the storage stability of the recording layer, improve the reflectance, protect the substrate from a solvent, guide grooves, and guide. It is used for forming pits and preformats. For the purpose of the polymer material, for example, ionomer resin, polyamide, vinyl resin, natural resin, natural polymer, silicone, various polymer compounds such as liquid rubber and silane coupling agent and the like can be used,
In addition to the above-mentioned polymer materials, inorganic compounds such as SiO ₂ , MgF ₂ , SiO, TiO ₂ , Z
nO, TiN, SiN, etc., and further, a metal or semimetal such as Zn, Cu, Ni, Cr, Ge, Se, A
u, Ag, Al and the like can be used. For the purpose, a metal such as Al, Au, Ag or the like, or an organic thin film having a metallic luster such as a methine dye or a xanthene-based dye can be used. Cured resin, thermosetting resin, thermoplastic resin, or the like can be used. The thickness of the undercoat layer is 0.
The thickness is suitably from 01 to 30 μm, preferably from 0.05 to 10 μm.

4) Reflective Layer The reflective layer can be made of a metal or semi-metal which is highly resistant to corrosion and can provide a high reflectance by itself. Examples of materials include Au,
Ag, Al, Cr, Ni, Fe, Sn and the like.
Au, Ag, and Al are most preferable in terms of reflectivity and productivity. These metals and metalloids may be used alone.
More than one kind of alloy may be used. Examples of the film forming method include vapor deposition and sputtering, and the film thickness is 50 to 50.
00 °, preferably 100-3000 °.

5) Protective Layer, Hard Coat Layer on Substrate Surface The protective layer or hard coat layer on the substrate surface protects the recording layer (reflection / absorption layer) from scratches, dust, dirt, etc., and preserves the recording layer (reflection / absorption layer). It is used for the purpose of improving the stability and the reflectance. For these purposes, the materials shown in the undercoat layer can be used. Also,
As an inorganic material, SiO, SiO _{2 and the} like can also be used, and as an organic material, polymethyl acrylate, polycarbonate, epoxy resin, polystyrene, polyester resin, vinyl resin, cellulose, aliphatic hydrocarbon resin,
Thermosoftening and heat melting resins such as natural rubber, styrene-butadiene resin, chloroprene rubber, wax, alkyd resin, drying oil, and rosin can also be used. The most preferable of the above materials is an ultraviolet curable resin having excellent productivity. The thickness of the protective layer or the hard coat layer on the substrate surface is 0.01 to 30 μm, preferably 0.05 to 10 μm.
Is appropriate.

6) Second substrate (protective substrate) When the second substrate (protective substrate) is irradiated with laser light from the second substrate side, it must be transparent to the laser light to be used. When used as a protective plate, transparency does not matter. The substrate material that can be used is exactly the same as the substrate material. Use a plastic such as polyester, acrylic resin, polyamide, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, polyimide, or glass, ceramic, or metal. Can be.

7) Adhesive and Adhesive Layer Any material can be used as long as it can bond the two recording media. From the viewpoint of productivity, an ultraviolet-curable or hot-melt adhesive is preferable.

In the present invention, the undercoat layer, the protective layer, and the hard coat layer on the substrate surface are formed in the same manner as in the case of the recording layer.
A stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer and the like can be contained.

[0055]

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

Example 1 A compound of the specific example No. 1 was prepared on an injection-molded polycarbonate substrate having a depth of 1600 mm, a half-value width of 0.32 μm and a guide groove having a track pitch of 0.8 μm and a thickness of 0.6 mm. 8 in a tetrafluoropropanol solution was applied by spinner coating to form an organic dye layer having a thickness of 700 .ANG., Then a reflective layer of 2000 .mu.m of gold was provided by sputtering, and further a 5 .mu.m Was provided to obtain a recording medium.

Examples 2 to 10 In Example 1, the specific compound Nos. Instead of 8,
Each of the specific compound Nos. 9, 13, 18, 23, 2
A recording medium was obtained in exactly the same manner as in Example 1, except that 8, 31, 36, 37, and 41 were used.

Comparative Examples 1 to 3 In Example 1, Compound Example Nos. 8, except that the following formulas (VI), (VII), and (VIII) were used in place of 8,
A recording medium was prepared in the same manner as in Example 1.

[0059]

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[0060]

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[0061]

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<Recording Conditions> Examples 1 to 10 and Comparative Example 1
EFM signals (linear velocity: 3.0 m / sec, shortest mark length: 0.4 μm) were recorded on the recording media of Nos. 1 to 3 using a semiconductor laser beam having an oscillation wavelength of 635 nm while tracking, and a continuous semiconductor laser having an oscillation wavelength of 650 nm was used. Reproduction was performed with light (reproduction power 0.7 mW), and the reflectance and C / N were measured. Table 8 shows the results. Light fastness test: Tungsten lamp, 50,000 lux, irradiation for 20 hours

<Evaluation results>

[Table 12]

Example 11 A compound represented by the above formula (VIII) was formed on a 1.2 mm thick injection molded polycarbonate substrate having a guide groove having a depth of 1500 °, a half width of 0.45 μm and a track pitch of 1.6 μm. Compound specific example No. And 1 in a weight ratio (1/1), and this was dissolved in tetrafluoropropanol,
A spinner coating is performed to form an organic dye layer having a thickness of 1700 °, a gold layer is formed by sputtering, and a reflective layer is formed to a thickness of 2000 °, and a 5 μm protective layer of acrylic photopolymer is further provided thereon. I got

Examples 12 to 16 In Example 11, the specific compounds Nos. In place of No. 1, respectively. A recording medium was obtained in exactly the same manner as in Example 11 except that 3, 4, 6, 26, and 40 were used.

Comparative Examples 3 and 4 In the same manner as in Example 11, except that the organic recording layer was made only of the compound represented by the formula (VIII) or only the compound represented by the following formula (IX), respectively. To obtain a recording medium. The compounds represented by formulas (VIII) and (IX) are both dyes used for CD-R.

[0067]

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<Reproduction Conditions> The recording media of Examples 11 to 16 and Comparative Examples 3 and 4 have an oscillation wavelength of 780 nm and a beam diameter of 1.0.
Using a 6 μm semiconductor laser, an EFM signal is recorded while tracking (linear velocity: 1.4 m / sec), and the laser and continuation light of the semiconductor laser having an oscillation wavelength of 650 nm and a beam diameter of 1.0 μm are reproduced, and a reproduction waveform is obtained. Observed. Table 13 shows the results.

<Evaluation results>

[Table 13]

[0070]

According to a first aspect of the present invention, there is provided an optical recording medium comprising a recording layer containing at least one counter ion compound of an azo metal chelate dye represented by the general formula (I) and a cyan dye. As a result, it has high light absorption and light reflectivity at a wavelength of 700 nm or less, so that recording and reproduction can be performed with laser light in a wavelength range of 700 nm or less, which enables high-density recording. Excellent storage stability.
The counter ion compound represented by the general formula (I) can be coated by coating, and can provide a high refractive index, a high modulation degree, and a low jitter media as compared with a single azo metal chelate counter ion compound. In addition, it is excellent in light resistance and storage stability as compared with a counter ion compound of a single cyanine dye.

An optical recording medium according to a second aspect is characterized in that at least one of the compounds represented by the above general formula (I) is combined with 680 to 7
Since the recording layer contains an organic dye having a maximum absorption wavelength at 50 nm, the recording layer can be used as a CD-R in the current system, and can be used in a next-generation high-density optical disk system. The reproduced information can be reproduced.

The optical recording medium according to claims 3 to 5, wherein the compound represented by the general formula (I) is a compound wherein A is an indolenine ring and B is a benzindolenine ring;
Or compounds A and B are shown in benzindolenine ring, or X and Y are O ^- or COO ^- since it was assumed to be a compound represented by the signal characteristics of the high quality becomes possible recording.

The optical recording medium according to claim 6 is 680 to 750.
Since at least one of a cyanine dye of pentamethine, a phthalocyanine dye and an azo metal chelate dye is selected as the organic dye having a maximum absorption wavelength in nm, it can be used as a high-quality CD-R in the current system.

The optical recording medium according to claim 7 is 630-690.
Recording and reproduction are performed by the first wavelength light of nm and the second wavelength light of 770 to 830 nm, that is, recording and reproduction can be performed in both the CD-R and DVD-R systems.

The optical recording medium according to claim 8 is 770-830.
nm, and reproduced by 630-690 nm wavelength light and 770-830 nm wavelength light, ie, can be used as a CD-R in current systems,
In addition, even in the case of a next-generation DVD-R system, recorded information can be reproduced.

[Brief description of the drawings]

FIGS. 1A to 1D are diagrams showing examples of a layer configuration as a general write-once optical recording medium applicable to the recording medium of the present invention.

FIGS. 2A to 2C are diagrams showing examples of a layer configuration for a high-reflectance optical recording medium (CD-R) applicable to the recording medium of the present invention.

FIGS. 3A to 3D are diagrams showing examples of a layer configuration for a large-capacity high-reflection optical recording medium (DVD-R) applicable to the recording medium of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Recording layer (organic dye layer) 3 Undercoat layer 4 Protective layer or adhesive layer 5 Hard coat layer 6 Reflective layer 7 Translucent reflective layer

Continued on the front page F term (reference) 2H111 EA03 EA12 EA32 EA40 FA01 FA11 FA12 FA14 FA15 FB42 FB43 FB45 5D029 JA04 JC17

Claims (8)

[Claims] 1. An optical recording medium comprising a recording layer provided directly or via an undercoat layer on a substrate, and a reflective layer, a protective layer or an adhesive layer, and a second substrate provided thereon as required.
An optical recording medium, characterized in that the recording layer contains at least one compound represented by the following general formula (I). General formula (I) [Wherein, R _{1 to} R ₅ , a to d, X, Y, M, n, A and B
Represents the following, respectively. R ₁ , R ₃ : hydrogen atom, halogen atom, nitro group, hydroxyl group, carboxy group, cyano group, sulfone group, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted heterocyclic ring Residue, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted Aryloxycarbonyl group, substituted or unsubstituted acyl group, substituted or unsubstituted acyloxy group or substituted or unsubstituted amino group, R ₂ , R ₄ : hydrogen atom, halogen atom, nitro group, hydroxyl group, carboxy group, Cyano group, sulfone group, substituted or unsubstituted alkyl group, substituted or unsubstituted Aryl group, substituted or unsubstituted heterocyclic residue, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted carbamoyl group, substituted or unsubstituted sulfonamide group, substituted or unsubstituted Substituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group, substituted or unsubstituted acyl group, substituted or unsubstituted acyloxy group or substituted or unsubstituted amino group, a, b, c, d: 0 to 0 An integer of 4, X, Y: a substituent comprising a hydroxy group, a carboxyl group, a sulfonic acid derivative, an amino group, M: a divalent or trivalent metal atom which may have oxygen, a halogen atom, etc., n: 1 Or an integer of 2, A, B: groups of atoms necessary to complete a heterocyclic ring, which may be the same or different, R ₅ : water An element atom or a monovalent substituent. ] 2. The optical recording medium according to claim 1, wherein the recording layer contains at least one compound represented by the general formula (I) and a dye having a maximum absorption wavelength at 680 to 750 nm. An optical recording medium characterized by the above-mentioned. 3. The optical recording medium according to claim 1, wherein
In the above general formula (I), A is a compound represented by an indolenine ring and B is a benzindolenine ring. 4. The optical recording medium according to claim 1, wherein
In the above general formula (I), A and B are compounds represented by a benzindolenine ring. 5. Any of the optical recording medium of claim 1, wherein in the general formula (I), X and Y are O ^- or CO
O ^- optical recording medium which is a compound represented by. 6. The optical recording medium according to claim 2, wherein
An optical recording medium characterized in that the dye having a maximum absorption wavelength at 750 nm is at least one of a cyanine dye of pentamethine, a phthalocyanine dye and an azo metal chelate compound. 7. The optical recording medium according to claim 2, wherein
The recording layer has a first wavelength light of 630 to 690 nm;
An optical recording medium which is recorded and reproduced by light having a second wavelength of 70 to 830 nm. 8. The optical recording medium according to claim 2, wherein
The recording layer is recorded with light having a wavelength of 770 to 830 nm, and light having a wavelength of 630 to 690 nm and 770 to 830 nm.
An optical recording medium reproduced by light having a wavelength of 30 nm.