JPH1035107A - Optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording material for an optical recording medium of superior light fastness and shelf-stability by containing a specified compound as a main component in a recording material. SOLUTION: A compound represented by the formula I is contained as a main component in a recording layer. R1 , R2 and R3 can be all the same or different respectively, and halogen, nitro, hydroxy, substituent or non-substituent alkyl, substituent or non-substituent alcoxy, substituent or non-substituent alkyl thio, substituent or non-substituent amino other than dialkylamino, or aryl, and R4 , R5 and R6 are nitro, halogen, hydroxy, substituent or non-substituent alkyl, substituent or non-substituent alcoxy, or substituent or non-substituent alkyl thio, and X is acidic anion or metal complex anion.

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 irradiating a light beam on a recording material to cause an optical change in transmittance and reflectance to record and reproduce information. And a recordable information recording medium,
Further, the present invention relates to a recording medium applicable to CD-I and CD-V.

[0002]

2. Description of the Related Art The current write-once optical disc system (WO
In the case of RM, CD-R), the recording medium uses a cyanine dye, a phthalocyanine dye, or the like as a recording material, and is configured so that recording and reproduction can be performed at a laser oscillation wavelength of 770 to 790 nm. The CD-R disk system also includes a cyanine dye / metal reflective layer, a phthalocyanine dye / metal reflective layer, an azo metal chelate dye / metal reflective layer, and the like.
A dye having a maximum absorption wavelength in the range of 0 to 730 nm is used.
The setting is such that a high reflectance is obtained at 0 nm.

[0003]

However, with the increase in the amount of information in the future, it is inevitable to increase the capacity of recording media, and accordingly, it is inevitable to shorten the laser wavelength used for recording and reproduction. However, an optical recording material which has excellent light resistance and storage stability and can be recorded and reproduced by an optical pickup using a laser of 700 nm or less has not yet been developed. The present invention has been made in view of such a situation,
Compared with the conventional system, it is applicable to a high-density optical disk system using a semiconductor laser having an oscillation wavelength in a short wavelength, and provides a recording material for an optical recording medium having excellent light resistance and storage stability. It is another object of the present invention to obtain a recording material for a CD-R recording medium that can be recorded and reproduced by the current system and can be reproduced by the next-generation high-density optical disk system.

[0004]

According to the present invention, first, in an information recording medium having a recording layer provided directly or via an undercoat layer on a substrate, the following general formula (I) An optical information recording medium comprising a compound represented by the following formula as a main component:

[0005]

Embedded image In the formula, R ₁ , R ₂ and R ₃ may be the same or different, and each may be a halogen, a nitro group, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted group. An alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ , R ₅ , and R ₆ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted An alkoxy group or a substituted or unsubstituted alkylthio group, X represents an acid anion or a metal complex anion, and l, m, and n represent an integer of 0 to 4.

Second, in an information recording medium having a recording layer provided directly on a substrate or via an undercoat layer, it is required that the recording layer contains a compound represented by the following general formula (II) as a main component. An optical information recording medium is provided.

[0007]

Embedded image In the formula, R ₁ and R ₂ may be the same or different,
Halogen, nitro group, hydroxy group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group,
A substituted or unsubstituted alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ and R ₅ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, An unsubstituted alkoxy group or a substituted or unsubstituted alkylthio group, R ₇ is a hydrogen atom, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted alkylthio group; Represents a group, a carboxylic acid ester residue, or an atom group forming a substituted or unsubstituted heterocyclic ring. X represents an acid anion or a metal complex anion, and l and m represent an integer of 0 to 4.

Third, in an information recording medium in which a recording layer is provided on a substrate directly or via an undercoat layer, it is preferable that the recording layer contains a compound represented by the following general formula (III) as a main component. An optical information recording medium is provided.

[0009]

Embedded image In the formula, R ₁ , R ₂ and R ₃ may be the same or different, and each may be a halogen, a nitro group, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted group. An alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ , R ₅ , and R ₆ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted An alkoxy group or a substituted or unsubstituted alkylthio group, X represents an acid anion or a metal complex anion, Y ₁ represents an oxygen atom or a sulfur atom, and l, m and n represent an integer of 0 to 4.

Fourth, in an information recording medium having a recording layer provided directly on a substrate or via an undercoat layer, it is preferable that the recording layer contains a compound represented by the following general formula (IV) as a main component. An optical information recording medium is provided.

[0011]

Embedded image In the formula, R ₁ and R ₂ may be the same or different,
Halogen, nitro group, hydroxy group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group,
A substituted or unsubstituted alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ and R ₅ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, An unsubstituted alkoxy group or a substituted or unsubstituted alkylthio group, R ₇ is a hydrogen atom, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted alkylthio group; Represents a group, a carboxylic acid ester residue, or an atom group forming a substituted or unsubstituted heterocyclic ring. X represents an acid anion or a metal complex anion, Y ₂ represents an oxygen atom or a sulfur atom, and l and m represent an integer of 0 to 4.

Fifth, the optical information recording medium according to any one of the first to fourth aspects, wherein the metal complex anion has an absorption ability in a longer wavelength region than the dye cation. Is provided.

Sixth, in any of the optical information recording media described in the first to fifth aspects, the metal complex anion has an absorption capacity in a longer wavelength region than the dye cation, and has an absorption capability in the recording / reproduction wavelength region. An optical information recording medium characterized by having no optical information is provided.

Seventh, in any one of the optical information recording media described in the first to sixth aspects, the recording layer further includes 68
An optical information recording medium comprising an organic dye having a maximum absorption wavelength at 0 to 750 nm is provided.

Eighth, in the optical information recording medium described in the seventh aspect, the organic dye is a cyanine dye of pentamethine;
An optical information recording medium characterized by being a phthalocyanine dye or an azo metal chelate dye is provided.

Hereinafter, the present invention will be described in detail. The present inventors have studied the above-mentioned problems, and as a result, by providing a recording layer containing a specific dye cation, that is, any of the compounds represented by the general formulas (I) to (IV) as a main component, Semiconductor laser with oscillation wavelength of 700 nm or less
It can be applied to a high-density optical disc system using a laser, and a mixture of any of the compounds represented by the above general formulas (I) to (IV) with an organic dye currently used as a recording material for CD-R. 700 nm by using
The present invention has been found that it is possible to obtain a high reflectance even in the following wavelength range, and it is possible to dramatically improve light resistance by using a metal complex anion as a counter ion of the compound of the above general formula. Reached.

[0017]

Embodiments of the present invention will be described below. 1 to 4 show a schematic structure of a recording medium of the present invention, and any of them can be used as a write-once optical disc for data. A sandwich structure in which these two pieces are bonded may be used. 3 and 4 can also be applied to a write-once compact disc.

Next, for each layer constituting the optical information recording medium of the present invention, necessary characteristics and examples of constituent materials will be described. First, as a necessary characteristic of the substrate to be used, the substrate must be transparent to the laser beam to be used only when recording and reproduction are performed from the substrate side, and need not be transparent when the recording and reproduction are performed from the recording layer side. As the substrate material, for example, polyester,
Plastic such as acrylic resin, polyamide, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, and polyimide, glass, ceramic, or metal 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.

The undercoat layer comprises (a) an improvement in adhesion, and (b)
Barrier for water or gas, (c) improvement of storage stability of recording layer, (d) improvement of reflectance, (e) protection of substrate from solvent, (f) guide groove, guide pit, preformat It is used for the purpose of forming, for example. For the purpose of (a), polymer materials, for example, various polymer materials such as ionomer resins, polyamide resins, vinyl resins, natural resins, natural polymers, silicones, liquid rubbers, and silane coupling agents are used. For the purposes of (b) and (c), inorganic compounds such as SiO ₂ , MgF ₂ , SiO, TiO ₂ , and Zn may be used in addition to the above polymer materials.
Metals, such as O, TiN, SiN, or semi-metals, eg, Z
n, Cu, Ni, Cr, Ge, Se, Au, Ag, Al
Etc. can be used. For the purpose of (d), a metal such as Al or Ag, or an organic thin film having a metallic luster such as a methine dye or a xanthene dye can be used, and the objects of (e) and (f) can be used. For example, an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin, or the like can be used. The thickness of the undercoat layer is suitably 0.01 to 30 μm, preferably 0.05 to 10 μm.

The recording layer causes some optical change by laser beam irradiation, and records information by the change. As described above, the recording layer includes the general formulas (I) and (I). It contains at least one of the compounds represented by (II), (III) and (IV) as a main component. In these compounds, X is a halogen ion, a perhalogenate ion,
It represents an acid anion such as an alkyl sulfate anion, a PF ₆ anion, a BF ₄ anion or a SbF ₆ anion, and a metal complex anion, and the metal complex anion is particularly excellent in light resistance. Further, it is preferable in terms of light resistance that the absorption spectrum is longer than the absorption spectrum of the dye cation, and it is more preferable in terms of sensitivity and reflectivity that it does not have an absorption capacity in the recording / reproducing wavelength range. General formula (I) or (II)
Tables 1 and 2 show specific examples of the compound represented by the formula, and Table 3 shows specific examples of the compounds represented by the general formulas (III) and (IV).
And Table 4 below.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

[0024]

[Table 4]

Further, as an example of the metal complex anion, a general formula
The compounds represented by (A) to (L) are shown below. Tables 5 and 6 show specific examples thereof.

[0026]

Embedded image In the formula, R ₁ and R ₂ represent a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group, or a heterocyclic residue. M is C
u, Co, Ni, Pd, or Pt.

[0027]

Embedded image In the formula, R ₁ , R ₂ , R ₃ , and R ₄ represent a hydrogen atom, a halogen, an alkyl group, an aryl group, a cycloalkyl group, or a heterocyclic residue bonded directly or indirectly via a divalent linking group. Represents M represents Cu, Co, Ni, Pd, or Pt.

[0028]

Embedded image In the formula, X represents S or CR ₁ R ₂ . R ₁ and R ₂ are CN,
COR ₃ , COOR ₄ , CONR ₅ R ₆ or SO ₂ R ₇ ,
Represents a group of atoms necessary to form a 5- or 6-membered ring, wherein R ₃ to R ₇ are a substituted or unsubstituted alkyl group,
Or an aryl group. M is Cu, Co, Ni, Pd,
Or Pt.

[0029]

Embedded image In the formula, R ₁ , R ₂ , R ₃ , and R ₄ represent a hydrogen atom, a halogen, an alkyl group, an aryl group, a cycloalkyl group, or a heterocyclic residue bonded directly or indirectly via a divalent linking group. Represents R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aryl group, an acyl group, a carboxyl group, or a sulfonyl group. M represents Cu, Co, Ni, Pd, or Pt.

[0030]

Embedded image In the formula, R ₁ , R ₂ , R ₃ , and R ₄ represent a hydrogen atom, a halogen, an alkyl group, an aryl group, a cycloalkyl group, or a heterocyclic residue bonded directly or indirectly via a divalent linking group. Represents R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aryl group, an acyl group, a carboxyl group, or a sulfonyl group. M represents Cu, Co, Ni, Pd, or Pt.

[0031]

Embedded image In the formula, R ₁ and R ₂ represent a hydrogen atom, an alkyl group, or an aryl group. R ₃ , R ₄ , R ₅ , and R ₆ represent a hydrogen atom, a halogen,
Represents an alkyl group or an aryl group. M is Cu, Co,
Represents Ni, Pd, or Pt.

[0032]

Embedded image In the formula, X represents O or S. R ₁ , R ₂ and R ₃ are directly
Or a substituted or unsubstituted alkyl, aryl, or cycloalkyl group bonded through an oxy group, a thio group, or an amino group. M is Cu, Co, Ni, P
represents d or Pt.

[0033]

Embedded image In the formula, R ₁ , R ₂ and R ₃ represent a substituted or unsubstituted alkyl group, aryl group or cycloalkyl group bonded directly or via an oxy group, a thio group or an amino group. X represents O or S. R ₄ represents an alkyl group or an aryl group. M is Cu, Co, Ni, Pd, or P
represents t.

[0034]

Embedded image In the formula, R ₁ and R ₂ represent a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group, or a heterocyclic residue. M is C
u, Co, Ni, Pd, or Pt.

[0035]

Embedded image In the formula, R ₁ , R ₂ , R ₃ , and R ₄ represent a hydrogen atom, a halogen, an alkyl group, an aryl group, a cycloalkyl group, or a heterocyclic residue bonded directly or indirectly via a divalent linking group. Represents M represents Cu, Co, Ni, Pd, or Pt.

[0036]

Embedded image In the formula, R ₁ , R ₂ , R ₃ , and R ₄ represent a hydrogen atom, a halogen, an alkyl group, an aryl group, a cycloalkyl group, or a heterocyclic residue bonded directly or indirectly via a divalent linking group. Represents R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aryl group, an acyl group, a carboxyl group, or a sulfonyl group. M represents Cu, Co, Ni, Pd, or Pt.

[0037]

Embedded image In the formula, R ₁ represents an alkyl group or an aryl group. R ₂ ,
R ₃ , R ₄ , and R ₅ represent a hydrogen atom, a halogen, an alkyl group, or an aryl group. M represents Cu, Co, Ni, Pd, or Pt.

[0038]

[Table 5]

[0039]

[Table 6]

The compound of the present invention has optical properties, recording sensitivity,
It may be used by mixing or laminating with other organic dyes, metals, and metal compounds for improving signal characteristics. in this case,
Organic dyes include polymethine dyes, naphthalocyanine, phthalocyanine, squarylium, coronium, pyrylium, naphthoquinone, anthraquinone (indanthrene), xanthene, triphenylmethane, azulene, tetrahydrocholine, Examples include phenanthrene-based, triphenothiazine-based dyes, and metal complex compounds. Examples of metals and metal compounds include I
n, Te, Bi, Se, Sb, Ge, Sn, Al, B
e, TeO ₂ , SnO, As and the like, and each of them can be used in a form of dispersion mixing or lamination.

In order to enable recording and reproduction in the current system and to enable reproduction only in the next-generation high-density optical disk system, the recording layer must be formed by the general formula (I)
Or a compound represented by (IV) and 680 to 750 nm
This is achieved by forming a mixed layer with an organic dye having the maximum absorption wavelength. Preferred specific examples of the organic dye having the maximum absorption wavelength at 680 to 750 nm are shown below.

[0042]

Embedded image (Cyanine dye) In the formula, R ₅ and R ₆ are an alkyl group having 1 to 3 carbon atoms, R
₇ , R ₈ are a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and X represents an acid anion. The aromatic ring may be condensed with another aromatic ring, and may be substituted with an alkyl group, a halogen, an alkoxy group, or an acyl group.

[0043]

Embedded image (Phthalocyanine dye) In the formula, M ₁ is Ni, Pd, Cu, Zn, Co, Mn, F
e, TiO, or VO, and X ₅ or X ₆ represents-at the α-position.
OR, -SR, or a hydrogen atom, but not all 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 ₅ to X ₈ are a hydrogen atom or a halogen.

[0044]

Embedded image (Phthalocyanine dye) In the formula, M ₂ is Si, Ge, In, or Sn, and X ₃ to X ₁₂ are —OR, SR, or a hydrogen atom at the α-position, and not all hydrogen atoms. Y ₃ and Y ₄ are -OSi
Represents RaRbRc, -OCORa, or -OPORaRb, and Ra, Rb, and Rc represent an alkyl group having 1 to 10 carbon atoms or an aryl group. Substituents on the benzene ring other than X ₃ to X ₁₂ are a hydrogen atom or a halogen.

[0045]

(Azo metal chelate compound) One or more azo metal chelate compounds of the azo compound represented by the formula (d) and a metal are used, and preferable examples of the metal include Ni, Pt, Co, Cu, and Zn. A represents a residue which forms a heterocyclic ring together with the carbon atom to which it is bonded and a nitrogen atom, and B represents an aromatic ring which is bonded together with the two carbon atoms to which it is bonded. Or a residue forming a heterocyclic ring;
Represents a group having active hydrogen.

Further, for the purpose of improving properties, a stabilizer (for example, a transition metal complex), a dispersant, a flame retardant, a lubricant, an antistatic agent,
It can be used together with a surfactant, a plasticizer and the like.
As a film forming method, a solvent casting method can be used, and the film thickness is 100 ° to 5 μm, preferably 300 ° to 2 μm.

The metal reflective layer is made of a metal, a semi-metal, or the like which is highly resistant to corrosion and can provide a high reflectance by itself. Examples of the material include Au, Ag, Cu, Cr, Ni, Al, Fe, and Sn. Are Au and A in terms of reflectance and productivity.
g and Al are most preferred. These metals and metalloids may be used alone or as two or more alloys. Examples of the film forming method include vapor deposition and sputtering, and the film thickness is 50 to 5000 °, preferably 100 to 30 °.
00 °.

The protective layer (a) protects the recording layer (reflection / absorption layer) from scratches, dust, dirt, etc .; (b) improves the storage stability of the recording layer (reflection / absorption layer); It is used for the purpose of improvement and the like. For these purposes, the materials shown in the undercoat layer can be used. Also,
As the inorganic material, SiO, SiO ₂ or the like can also be used. As the organic material, polymethyl acrylate, polycarbonate, epoxy resin, polystyrene, polyester resin, vinyl resin, cellulose, aliphatic hydrocarbon resin, aromatic hydrocarbon resin, natural Thermosoftening and heat melting resins such as rubber, styrene butadiene resin, chloroprene rubber, wax, alkyd resin, drying oil and rosin can also be used. The most preferable material for the protective layer among 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 suitable.

In the present invention, the undercoat layer, the protective layer,
In addition, the hard coat layer on the substrate surface may contain a stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, and the like, as in the case of the recording layer.

[0050]

EXAMPLES The present invention will be described below with reference to examples.

[Example 1] Depth 1000 °, half width 0.
1. Thickness having guide grooves of 35 μm and pitch of 1.0 μm
Compound N on a 2 mm injection molded polycarbonate substrate
O. 2,2,3,3-tetrafluoropropanol solution of the compound of formula (2) was spin-coated to form an organic dye layer having a thickness of 1300.degree.
A reflective layer was formed, and a 2 μm protective layer of an acrylic photopolymer was further provided thereon to obtain a recording medium.

Example 2 In Example 1, compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound of No. 7 was used.

Example 3 In Example 1, the compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound No. 8 was used.

Example 4 In Example 1, compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound of No. 10 was used.

Example 5 The compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that Compound 17 was used.

Example 6 In Example 1, compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1, except that Compound 21 was used.

Example 7 In Example 1, compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound No. 28 was used.

Example 8 In Example 1, the compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound No. 31 was used.

Example 9 In Example 1, compound NO. In place of compound No. 2, compound NO. A recording medium was formed in the same manner as in Example 1 except that the compound No. 44 was used.

[Comparative Example 1] In Example 1, compound NO. A recording medium was formed in the same manner as in Example 1 except that the following compound (compound NO. Ratio-1) was used instead of the compound of No. 2.

[0061]

Embedded image (ratio -1)

A light fastness test was performed on the recording media of the examples and the comparative examples manufactured as described above under the following recording conditions. Table 7 shows the evaluation results. <Recording conditions> Using a semiconductor laser having an emission wavelength of 635 nm and a beam diameter of 1.2 μm for each recording medium, an EFM signal was recorded while tracking (linear velocity: 1.4 m / sec), and reproduced with continuous light of the same laser. The reproduced waveform was observed.

[0063]

[Table 7]

Example 10 A compound (compound No. 1) used in Comparative Example 1 was placed on a 1.2 mm-thick injection-molded polycarbonate substrate having a guide groove with a depth of 1000 mm, a half width of 0.45 μm, and a pitch of 1.6 μm. Ratio-1) and compound N
O. 2,2,3,3 where the compound of No. 8 was 1/1 by weight ratio
Spinner coating the tetrafluoropropanol solution,
An organic dye layer having a thickness of 1600 ° was formed, and then a gold and a reflective layer having a thickness of 2000 ° were formed by a sputtering method, and a 2 μm protective layer of an acrylic photopolymer was further provided thereon to obtain a recording medium.

Example 11 In Example 10, the compound N
O. In place of compound No. 8, compound NO. A recording medium was formed in the same manner as in Example 10 except that Compound 17 was used.

Example 12 In Example 10, the compound NO.
In place of compound No. 8, compound NO. A recording medium was formed in the same manner as in Example 10, except that Compound 23 was used.

Example 13 In Example 10, the compound NO.
In place of compound No. 8, compound NO. A recording medium was formed in the same manner as in Example 10, except that Compound 31 was used.

Example 14 In Example 10, the compound NO.
In place of compound No. 8, compound NO. A recording medium was formed in the same manner as in Example 10 except for using the compound No. 36.

Example 15 The compound NO.
In place of compound No. 8, compound NO. A recording medium was formed in the same manner as in Example 10 except that the compound of No. 47 was used.

[Comparative Example 2] In Example 10, compound NO. 8
The same compound as used in Comparative Example 1 in place of the compound
A recording medium was formed in the same manner as in Example 10 except that (compound NO. Ratio-1) was used.

The following tests were carried out under the following recording conditions for the recording media of the examples and the comparative examples produced as described above. Table 8 shows the evaluation results. <Recording conditions> An EFM signal was recorded while tracking using a semiconductor laser having an oscillation wavelength of 780 nm and a beam diameter of 1.6 μm on each recording medium (linear velocity of 1.4 m / s).
ec) Reproduction was performed with continuous light from the same laser and a semiconductor laser having a transmission wavelength of 635 nm and a beam diameter of 1.2 μm, and the reproduction waveform was observed.

[0072]

[Table 8]

[0073]

As described above, according to the configurations described in the first to fourth aspects, high-density optical information recording which is recordable and reproducible with laser light in a wavelength region of 700 nm or less and has excellent light resistance is provided. A medium is obtained. Further, according to the configuration described in the fifth aspect, a recording medium further improved in light resistance of the recording medium obtained from the configuration described in the first to fourth aspects can be obtained. Further, according to the configuration described in the sixth aspect, a recording medium obtained by further improving the sensitivity and the reflectance characteristics of the recording medium obtained from the configurations described in the first to fifth aspects can be obtained. Further, according to the configuration described in the seventh aspect, it is possible to obtain an optical information recording medium that can be recorded and reproduced by the current system and can be reproduced by the high-density optical disk system. According to the configuration described in the eighth aspect, an optimal configuration of the recording medium obtained from the configuration described in the seventh aspect can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a recording medium of the present invention.

FIG. 2 is a diagram showing another configuration example of the recording medium of the present invention.

FIG. 3 is a diagram showing still another configuration example of the recording medium of the present invention.

FIG. 4 is a diagram showing still another configuration example of the recording medium of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Recording layer 3 Undercoat layer 4 Protective layer 5 Metal reflective layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C09B 11/28 C09B 11/28 B G11B 7/24 516 8721-5D G11B 7/24 516 // C07D 209/14 C07D 209/14 213/76 213/76 311/82 311/82 335/10 335/10 (72) Inventor Yasunobu Ueno 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (8)

[Claims] 1. An optical information recording medium in which a recording layer is provided directly on a substrate or via an undercoat layer, or a metal reflective layer and a protective layer are further provided on the recording layer, An optical information recording medium comprising a compound represented by the general formula (I) as a main component. Embedded image In the formula, R ₁ , R ₂ and R ₃ may be the same or different, and each may be a halogen, a nitro group, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted group. An alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ , R ₅ , and R ₆ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted An alkoxy group or a substituted or unsubstituted alkylthio group, X represents an acid anion or a metal complex anion, and l, m, and n represent an integer of 0 to 4. 2. An optical information recording medium in which a recording layer is provided directly on a substrate or through an undercoat layer, or a metal reflective layer and a protective layer are further provided on the recording layer, An optical information recording medium comprising a compound represented by the general formula (II) as a main component. Embedded image In the formula, R ₁ and R ₂ may be the same or different,
Halogen, nitro group, hydroxy group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group,
A substituted or unsubstituted alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ and R ₅ are a nitro group, a halogen, a hydroxy group,
A substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted alkylthio group, R ₇ is a hydrogen atom, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted Represents an alkoxy group, a substituted or unsubstituted alkylthio group, a carboxylic ester residue, or a group of atoms forming a substituted or unsubstituted heterocycle. X is an acid anion,
Or, a metal complex anion, l and m represent an integer of 0 to 4. 3. An optical information recording medium in which a recording layer is provided directly on a substrate or through an undercoat layer, or a metal reflective layer and a protective layer are further provided on the recording layer, An optical information recording medium comprising a compound represented by the general formula (III) as a main component. Embedded image In the formula, R ₁ , R ₂ and R ₃ may be the same or different, and each may be a halogen, a nitro group, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted group. An alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ , R ₅ , and R ₆ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted An alkoxy group or a substituted or unsubstituted alkylthio group, X represents an acid anion or a metal complex anion, Y ₁ represents an oxygen atom or a sulfur atom, and l, m and n represent an integer of 0 to 4. 4. An optical information recording medium in which a recording layer is provided directly on a substrate or through an undercoat layer, or a metal reflective layer and a protective layer are further provided on the recording layer, An optical information recording medium comprising a compound represented by the general formula (IV) as a main component. Embedded image In the formula, R ₁ and R ₂ may be the same or different,
Halogen, nitro group, hydroxy group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group,
A substituted or unsubstituted alkylthio group, an amino group other than a substituted or unsubstituted dialkylamino group, or an aryl group, R ₄ and R ₅ are a nitro group, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, An unsubstituted alkoxy group or a substituted or unsubstituted alkylthio group, R ₇ is a hydrogen atom, a halogen, a hydroxy group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group , A carboxylic acid ester residue, or a group of atoms forming a substituted or unsubstituted heterocyclic ring. X represents an acid anion or a metal complex anion, Y ₂ represents an oxygen atom or a sulfur atom, and l and m represent an integer of 0 to 4. 5. The optical information recording medium according to claim 1, wherein the metal complex anion has an absorption ability in a longer wavelength region than the dye cation. 6. The optical information recording medium according to claim 1, wherein the metal complex anion has an absorption ability in a longer wavelength region than the dye cation and has no absorption ability in a recording / reproducing wavelength region. Characteristic optical information recording medium. 7. The optical information recording medium according to claim 1, further comprising 680 to 750 n in a recording layer.
An optical information recording medium characterized by containing an organic dye having a maximum absorption wavelength in m. 8. The optical information recording medium according to claim 7, wherein the organic dye is a pentamethine cyanine dye, a phthalocyanine dye, or an azo metal chelate dye.