JPH11221964A - Optical recording medium - Google Patents

Abstract

(57) [Problem] To provide an optical recording medium corresponding to a blue laser beam. SOLUTION: In an optical recording medium provided with a recording layer on which information can be written and / or read by a laser on a substrate, the recording layer has the following general formula (I): (Wherein, R ^{1 to} R ⁴ each independently represent an aromatic ring or a heterocyclic ring which may have a substituent, and X ^{1 to} X ⁸
Each independently represents a hydrogen atom, a halogen atom or a nitro group, and M represents a hydrogen atom or a metal. An optical recording medium containing a porphyrin compound represented by the formula (1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an optical recording medium using a porphyrin compound as a recording layer. Specifically, the present invention relates to an optical recording medium corresponding to blue laser light.

[0002]

2. Description of the Related Art In recent years, optical recording using a laser has been particularly developed in order to enable high-density information recording and storage and reproduction thereof. An example of the optical recording medium is an optical disk. Generally, an optical disc has a thickness of 1 μm on a thin recording layer provided on a circular substrate.
It is to irradiate a laser beam which has been converged to a certain degree to record high-density information. One of the optical disks that has recently attracted attention is a writable compact disk (C
DR). A CD-R is generally formed by sequentially laminating a recording layer mainly composed of a dye, a metal reflective film, and a protective film on a plastic substrate having a guide groove. The record of information is
The absorption of the irradiated laser light energy causes thermal deformation such as decomposition, evaporation, and dissolution in the recording layer, reflective layer or substrate at that location. This is performed by reading the difference in reflectance between a portion where deformation has occurred due to light and a portion where deformation has not occurred. Therefore, it is necessary to efficiently absorb the energy of laser light as an optical recording medium, and a laser absorbing dye is used.

An optical recording medium using such an organic dye is expected to become more and more popular as an inexpensive optical recording medium because a recording layer can be formed by a simple method by applying an organic dye solution. There is a demand for higher density. Therefore, the laser light used for recording is
It has been studied to shorten the wavelength from a semiconductor laser centered on 0 nm to a blue light region.

[0004]

An object of the present invention is to provide an optical recording medium using a porphyrin compound as an optical recording medium corresponding to a blue laser beam.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve this object, and as a result, an optical recording medium using a porphyrin compound represented by the following general formula (I) in a recording layer is a blue laser. We found that we could record well. That is, the present invention relates to an optical recording medium having a recording layer on which information can be written and / or read by a laser on a substrate, wherein the recording layer has the following general formula (I)

[0006]

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(Wherein, R ^{1 to} R ⁴ each independently represent an aromatic ring or a heterocyclic ring which may have a substituent; X ^{1 to} X ⁸ each independently represent a hydrogen atom; An optical recording medium characterized by containing a porphyrin compound represented by a halogen atom or a nitro group, and M representing a hydrogen atom or a metal.

[0008] The porphyrin compound in the present invention comprises 4
It has a large molar extinction coefficient in the blue light region of 00 to 500 nm, has a sharp absorption (Soret band), and is suitable for recording with a blue laser. Further, since synthesis is relatively easy among porphyrin compounds, an inexpensive optical recording medium can be provided. It has high light stability and heat resistance, and is suitable for an optical recording medium requiring stability.
Hereinafter, the present invention will be described in detail.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the above general formula (I), R ¹
As the optionally substituted aromatic or heterocyclic ring represented by R ⁴ , a benzene ring, a naphthalene ring, an anthracene ring, an indene ring, a phenanthrene ring, a thiophene ring, a furan ring, a pyrrole ring, a pyrazole ring, an imidazole ring,
Triazole ring, oxazole ring, thiazole ring, thiadiazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, pyran ring, indene ring, benzofuran ring, indole ring, benzothiophene ring, benzimidazole ring, benzothiazole ring And a quinoline ring, a coumarin ring, a quinoxaline ring, an azulene ring, a fluorene ring, a dibenzofuran ring, a carbazole ring, an acridine ring, a phenanthroline ring, and a phenothiazine ring. Among them, a benzene ring, a pyridine ring and a thiophene ring are particularly preferred.

The substituent on the aromatic ring or the heterocyclic ring is a hydrogen atom; methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, se
a linear or branched alkyl group having 1 to 20 carbon atoms such as a c-butyl group, an n-pentyl group, or an n-hexyl group; a C3-10 alkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, or a cyclohexyl group; Cycloalkyl group; methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, tert-butoxy group, ethoxycarbonylpropoxy group, sec-butoxy group, n
An optionally substituted linear or branched C1-C20 alkoxy group such as a pentyloxy group, an n-hexyloxy group; an acetyl group, a propionyl group, a butyryl group,
2 carbon atoms such as isobutyryl, valeryl, isovaleryl, pivaloyl, hexanoyl, heptanoyl, etc.
To 21 linear or branched alkylcarbonyl groups; linear or branched alkenyl groups having 2 to 20 carbon atoms such as vinyl group, propenyl group, butenyl group, pentenyl group, and hexenyl group, or corresponding alkenyloxy groups, and cyclopentenyl A C3-10 cycloalkenyl group such as a cyclohexenyl group; a halogen atom such as a fluorine atom, a chlorine atom or a bromine atom; a formyl group; a hydroxyl group; a carboxyl group; a carbon number such as a hydroxymethyl group or a hydroxyethyl group 1-20 hydroxyalkyl groups; methoxycarbonyl group, trifluoromethoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, isopropoxycarbonyl group, n-butoxycarbonyl group, t
a linear or branched alkoxycarbonyl group having 2 to 21 carbon atoms which may be substituted, such as an tert-butoxycarbonyl group, a sec-butoxycarbonyl group, an n-pentyloxycarbonyl group, an n-hexyloxycarbonyl group; methylcarbonyl Oxy group, ethylcarbonyloxy group, n-propylcarbonyloxy group, isopropylcarbonyloxy group, n-butylcarbonyloxy group,
An optionally substituted straight chain having 2 to 21 carbon atoms such as a trifluoroethylcarbonyloxy group, a tert-butylcarbonyloxy group, a sec-butylcarbonyloxy group, an n-pentylcarbonyloxy group, and an n-hexylcarbonyloxy group. Or a branched alkylcarbonyloxy group; a nitro group; a cyano group; an amino group; a methylamino group;
Ethylamino group, n-propylamino group, n-butylamino group, dimethylamino group, diethylamino group, di-n
-Propylamino group, di-iso-propylamino group,
A linear or branched C1-C20 alkylamino group such as a di-n-butylamino group or a di-sec-butylamino group; a diphenylamino group; a C3-C9 group such as a trimethylamino group or a triethylamino group. A methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, an n-propoxyethyl group,
n-propoxypropyl group, isopropoxymethyl group,
A linear or branched alkoxyalkyl group having 2 to 21 carbon atoms such as an isopropoxyethyl group; methoxycarbonylmethyl group, methoxycarbonylethyl group, ethoxycarbonylmethyl group, ethoxycarbonylethyl group, n-propoxycarbonylethyl group, n- A straight-chain or branched alkoxycarbonylalkyl group having 3 to 22 carbon atoms such as a propoxycarbonylpropyl group, an isopropoxycarbonylmethyl group, an isopropoxycarbonylethyl group; a methylthio group, an ethylthio group, an n-propylthio group, an isopropylthio group; -Butylthio group, tert-butylthio group, sec-butylthio group, n-pentylthio group, n
A straight-chain or branched alkylthio group having 1 to 20 carbon atoms such as a hexylthio group; methylsulfonyl group, ethylsulfonyl group, fluoroethylsulfonyl group, n-propylsulfonyl group, isopropylsulfonyl group, n-butylsulfonyl group, tert- Butylsulfonyl group, sec-
Butylsulfonyl group, n-pentylsulfonyl group, n-
A linear or branched alkylsulfonyl group having 1 to 20 carbon atoms which may be substituted, such as a hexylsulfonyl group; a phenyl group which may have a substituent; a phenoxy group which may have a substituent; which may have a substituent phenylthio ^{group; -CR 5 = C (CN)} R 6 (R 5 is a hydrogen atom, or a straight-chain or branched alkyl group having 1 to 6 carbon atoms, R ⁶ is cyano A group or a straight-chain or branched alkoxycarbonyl group having 2 to 7 carbon atoms,
Represents a linear or branched fluorinated alkoxycarbonyl group. ); Trifluoromethyl, pentafluoroethyl, heptafluoro-n-propyl, heptafluoroisopropyl, perfluoro-n-butyl, perfluoro-tert-butyl, perfluoro-sec
A butyl group, a perfluoro-n-pentyl group, a linear or branched fluoroalkyl group having 1 to 20 carbon atoms such as a perfluoro-n-hexyl group; a trifluoromethoxy group,
Pentafluoroethoxy group, heptafluoro-n-propoxy group, heptafluoroisopropoxy group, perfluoro-n-butoxy group, perfluoro-tert-butoxy group, perfluoro-sec-butoxy group, perfluoro-n-pentyloxy Group, perfluoro-n-hexyloxy group, bromododecyloxy group, etc.
0 straight-chain or branched haloalkoxy group; trifluoromethylthio group, pentafluoroethylthio group, heptafluoro-n-propylthio group, heptafluoroisopropylthio group, perfluoro-n-butylthio group, perfluoro-tert-butylthio Group, perfluoro-se
C-butylthio group, perfluoro-n-pentylthio group, perfluoro-n-hexylthio group, etc.
20 straight-chain or branched haloalkylthio groups; and the number of substitution may be one or more. When the aromatic ring is a benzene ring, a pyridine ring, or the like, the substituent is preferably substituted at the ortho or meta position.

The counter ion in the case of the above trialkylamino group
Is not particularly limited as long as it is an anion.^-, Cl
^-, Br^-, I^-, CH_ThreeCOO^-, CF_ThreeCOO^-,
BF _Four ^-, PF₆ ^-, ClO_Four ^-,

[0012]

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And the like. When the aromatic ring is a nitrogen-containing heterocyclic ring such as a pyrrole ring or a pyridine ring, the substituent may be introduced in a form that quaternizes the nitrogen atom.
The counterion in this case is not particularly limited as long as it is an anion, and examples thereof include the same anions as those of the trialkylamino group. In the general formula (I), X ¹ to
X ⁸ each independently represents a hydrogen atom; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom, or a nitro group.

In the general formula (I), M is a hydrogen atom or a metal atom. As metal atoms, Mg, Al, Si, Ca, Sc, Ti, V, Cr,
Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, A
s, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh,
Pd, Ag, Cd, In, Sn, Sb, Ba, Pr, E
u, Yb, Hf, Ta, W, Re, Os, Ir, Pt,
There is no particular limitation on metals such as Au, Hg, Tl, Pb, Bi, and Th, which are generally capable of coordinating with porphyrin-based compounds. In particular, Mg, Al, Si, Ti, V, Mn, F
e, Co, Ni, Cu, Zn, Ga, Ge, Pd, I
n, Sn, Pb and the like are preferable. In addition, Fe, In, Sn
For metals etc., ^F as the axial ligand ^-, Cl -, Br
^-, I ^- and halogen ^{ions; OR -, NCS -, N} 3
^{-, OH -, CN -,} CH 3 COO -, CF 3 CO
An anion such as O ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , tosyloxy, phenoxy; a base such as pyridine or imidazole; a gas such as NO, CO or O ₂ ; Here, R is a group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, a sec-butyl group, an n-pentyl group, and an n-hexyl group. Represents a linear or branched alkyl group. Examples of the porphyrin compound of the present invention include those having the following structures.

[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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These porphyrin compounds may be used singly or as a mixture of several types. The metal-free porphyrin-based compound represented by the general formula (I) can be prepared, for example, by mixing an aldehyde derivative represented by the following general formula (II) and a pyrrole derivative represented by the following general formula (III) in an organic solvent such as propionic acid. It can be synthesized by heating. When two or more aldehyde derivatives are used, a mixture can be obtained. By performing separation and purification using a column or the like, a predetermined substituted product can be obtained.

[0025]

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(Wherein, R has the same meaning as the above-mentioned optionally substituted aromatic or heterocyclic ring represented by R ^{1 to} R ⁴ , and X and X ′ are respectively the above-mentioned X ¹ to X ⁴ . the definition and the meaning of X ^8.)

The metal-free porphyrin compound synthesized by the above method is used in an organic solvent such as acetic acid, N, N-dimethylformamide, benzene, ether, chloroform, pyridine and the like in a halide, acetate, metal acetylacetonate complex, metal carbonyl. By heating with a metal salt such as a complex, a porphyrin compound into which the central metal M has been introduced is synthesized.

The substituent may be introduced into the aromatic ring or the heterocyclic ring before or after the porphyrin ring is formed. For example, the introduction of a substituent into a pyridine ring or the like after the formation of a porphyrin ring can be achieved by converting the porphyrin compound obtained above with a halide such as alkyl bromide and N, N-
It is carried out by heating in an organic solvent such as dimethylformamide in the presence of a base such as potassium carbonate. Also,
In the general formula (I), a compound in which any ^one of X ^{1 to} X ⁸ is a halogen atom is obtained by halogenating the porphyrin compound obtained by the above method using a halogenating agent. It can also be obtained by nitrating with an agent.

The optical recording medium of the present invention basically comprises at least a substrate and a recording layer containing the porphyrin-based compound. If necessary, an undercoat layer may be provided on the substrate. be able to. The substrate is preferably transparent to a laser beam to be used, and glass and various plastics are used. As plastics, acrylic resin, methacrylic resin, polycarbonate resin, vinyl chloride resin, vinyl acetate resin,
Examples thereof include nitrocellulose, polyester resin, polyethylene resin, polypropylene resin, polyimide resin, polystyrene resin, and epoxy resin, and the injection molded polycarbonate resin substrate is particularly preferable in terms of high productivity, cost, and moisture absorption resistance.

The thickness of the recording layer containing the porphyrin compound in the optical recording medium of the present invention is from 100 ° to 5 μm.
m, preferably between 700 ° and 3 μm. As a method of forming the recording layer, a vacuum deposition method, a sputtering method, a doctor blade method, a casting method, a spinner method, a film forming method which is generally performed such as a dipping method can be used.
The spinner method is preferable in terms of mass productivity and cost.

The recording layer may be composed of a porphyrin-based compound alone, but a binder may be used if necessary. Known binders such as polyvinyl alcohol, polyvinyl pyrrolidone, ketone resin, nitrocellulose, cellulose acetate, polyvinyl butyral, and polycarbonate are used as the binder. In this case, the porphyrin compound of the present invention is preferably contained in the resin in an amount of 10% by weight or more.

In the case of film formation by the spinner method, the number of rotations is 5
00-5000 rpm is preferable, and after spin coating,
Depending on the case, a treatment such as heating or exposure to a solvent vapor may be performed. In order to improve the stability and light resistance of the recording layer, a transition metal chelate compound (for example, a chelate such as acetylacetonate, bisphenyldithiol, salicylaldehyde oxime, bisdithio-α-diketone) or the like is used as a singlet oxygen quencher. Further, a recording sensitivity improver such as a metal compound may be contained for improving the recording sensitivity. Here, the metal compound refers to a compound in which a metal such as a transition metal is contained in the compound in the form of an atom, an ion, a cluster, or the like, for example, an ethylenediamine-based complex, an azomethine-based complex, a phenylhydroxyamine-based complex, a phenanthroline-based complex, Organometallic compounds such as dihydroxyazobenzene-based complexes, dioxime-based complexes, nitrosoaminophenol-based complexes, pyridyltriazine-based complexes, acetylacetonate-based complexes, metallocene-based complexes, and porphyrin-based complexes are exemplified. The metal atom is not particularly limited, but is preferably a transition metal.

Further, if necessary, other dyes can be used in combination. Other dyes mainly absorb in the laser wavelength range for recording and absorb the irradiated laser light energy to cause the recording layer, reflective layer or substrate at that location to thermally decompose, evaporate, dissolve, etc. There is no particular limitation as long as pits are formed with deformation. The coating solvent for forming the recording layer by a coating method such as a doctor blade method, a casting method, a spinner method, an immersion method, especially a spinner method is not particularly limited as long as it does not attack the substrate.
For example, diacetone alcohol, 3-hydroxy-3-
Ketone alcohol solvents such as methyl-2-butanone, cellosolve solvents such as methyl cellosolve and ethyl cellosolve, hydrocarbon solvents such as n-hexane and n-octane;
Hydrocarbon solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, n-butylcyclohexane, t-butylcyclohexane, cyclooctane, ether solvents such as diisopropyl ether and dibutyl ether, tetrafluoropropanol, octafluoropentanol, Examples include perfluoroalkyl alcohol solvents such as hexafluorobutanol, and hydroxyester solvents such as methyl lactate, ethyl lactate, and methyl isobutyrate.

Further, a metal reflective layer such as gold, silver, aluminum or an alloy thereof and a protective layer may be provided on the recording layer to provide a medium having high reflectivity. Gold, silver,
Aluminum and the like can be mentioned, but with gold or aluminum, the reflectance is not sufficient for the laser light having a wavelength of 530 nm or less used in the present invention, and silver is preferable. The metal reflection layer is formed by a vapor deposition method, a sputtering method, an ion plating method, or the like. Note that an intermediate layer may be provided between the metal reflective layer and the recording layer for the purpose of improving the adhesion between the layers or for the purpose of increasing the reflectance. Examples of the protective layer include a UV curable resin composition. Further, a double-sided recording type optical recording medium may be bonded through an adhesive layer, or the recording layer may be provided on both sides of the substrate, or may be provided on one side.

The laser beam used for the optical recording medium of the present invention is preferably shorter in wavelength for high-density recording, but a laser beam of 350 nm to 530 nm is particularly preferable. Representative examples of such a laser include a central wavelength of 410 nm,
545 nm laser. Wavelength 350nm ~
An example of a laser beam in the range of 530 nm can be obtained by using a high-power semiconductor laser of 410 nm blue or 515 nm bluish green. In addition, for example, (a) continuous oscillation having a fundamental oscillation wavelength of 740 to 960 nm A semiconductor laser which is capable of continuous oscillation having a fundamental oscillation wavelength of 740 to 960 nm, which is excited by the semiconductor laser and (b) is obtained by wavelength conversion by a second harmonic generation element (SHG). Can be done.

[0036]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the invention unless it exceeds the gist thereof. Example 1 (a) Synthesis of porphyrin compound 10.7 g (100 mmol) of isonicotinaldehyde
Was stirred and refluxed, and 6.71 g (100 mmol) of pyrrole was slowly added dropwise thereto. After refluxing for 1 hour, the solution is left to cool, and the precipitated crystals are collected by filtration and purified with an alumina column to give 5,10,15,20-tetra (4-pyridyl) represented by the following structural formula (V).
1.79 g of porphyrin (11.6% yield) was obtained. The λmax of this compound in chloroform was 417n.
m and the molar extinction coefficient was 3.83 × 10 ⁵ .
FIG. 1 shows the visible spectrum absorption spectrum of this compound in a chloroform solution.

[0037]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (V)
Prepare an octafluoropentanol solution, filter,
A lysate was obtained. This solution was prepared with a diameter of 120 mm and a thickness of 1.2.
mm on an injection molded polycarbonate resin substrate,
It was applied by a spinner method. After the application, it was dried at 100 ° C. for 30 minutes. Next, a silver film having a thickness of 1000 ° was formed on this coating film by a sputtering method to form a reflection layer. Further, an ultraviolet-curable resin is spin-coated on the reflective layer, and is cured by irradiating ultraviolet rays onto the resin.
A protective layer having a thickness of μm was formed. The maximum absorption wavelength of the coating film (recording layer) was 435 nm. FIG. 2 shows the absorption spectrum of the visible region of the coating film. The reflectance of the obtained optical recording medium at 488 nm was 55%.

(C) Optical Recording Method When the above optical recording medium was irradiated with argon laser light having a center wavelength of 488 nm, good recording pits could be formed.

Example 2 (a) Synthesis of porphyrin compound 4.07 g (38 mmol) of isonicotinaldehyde
A solution of 13.5 g (112 mmol) of p-tolualdehyde in 500 ml of propionic acid was stirred and refluxed, and 10.1 g (150 mmol) of pyrrole was slowly added dropwise thereto. After refluxing for 1 hour, the solution was left to cool, and the precipitated crystals were collected by filtration and purified with a silica gel column to give 5,10,15-tri (4-tolyl) -20- (4-tol) represented by the following structural formula (VI).
0.50 g (yield 2.0%) of pyridyl) porphyrin were obtained.

Next, 0.10 g of compound (VI) (0.15 m
mol), 0.25 g of n-hexyl bromide (1.52
mmol) and 90 ml of N, N-dimethylformamide were heated and refluxed under a nitrogen atmosphere for 3 hours. After allowing to cool, the solvent is removed under reduced pressure, and the residue is purified by a silica gel column to give 5,10,15-tri (4-tolyl) -20- [4-N- (n-hexyl) represented by the following structural formula (VII). ) Pyridyl] porphyrin, bromide 0.11 g (yield 8
5.5%). The λmax of this compound in chloroform was 422 nm, and the molar extinction coefficient was 1.50.
× 10 ⁵ . FIG. 3 shows the absorption spectrum of the visible portion of this compound in a chloroform solution.

[0042]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (VII)
Using an octafluoropentanol solution, coating was performed on a polycarbonate resin substrate in the same manner as in Example 1, and then a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film is 435
nm. FIG. 4 shows the absorption spectrum of the visible region of the coating film. The reflectance of the obtained optical recording medium at 488 nm was 60%.

(C) Optical Recording Method When the above optical recording medium was irradiated with an argon laser beam having a center wavelength of 488 nm, good recording pits could be formed.

Example 3 (a) Synthesis of porphyrin compound 0.13 g (0.20 m) of the compound represented by the structural formula (VI)
mol), and 0.48 g (1.68) of farnesyl bromide.
mmol), N, N-dimethylformamide 120 ml
Was heated and refluxed under a nitrogen atmosphere for 3 hours. After allowing to cool, the solvent is removed under reduced pressure and the residue is purified by a silica gel column to give 5,10,15- represented by the following structural formula (VIII).
Tri (4-tolyl) -20- [4-N-farnesylpyridyl] porphyrin, 0.019 g of bromide (yield 1
0.2%).

The λmax of this compound in chloroform was 422 nm, and the molar extinction coefficient was 1.33 × 10 ⁵ . FIG. 5 shows the visible light absorption spectrum of this compound in a chloroform solution.

[0047]

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(B) Production of recording medium A 1% by weight solution of a porphyrin compound represented by the structural formula (VIII) in octafluoropentanol was applied on a polycarbonate resin substrate in the same manner as in Example 1; A protective layer was formed. The maximum absorption wavelength of the coating film is 43
It was 3 nm. Fig. 6 shows the absorption spectrum of the visible region of the coating film.
Shown in The reflectance of the obtained optical recording medium at 488 nm was 62%.

(C) Optical Recording Method When the above optical recording medium was irradiated with an argon laser beam having a center wavelength of 488 nm, good recording pits could be formed.

Example 4 (a) Synthesis of porphyrin compound 0.13 g (0.20 m) of the compound represented by the structural formula (VI)
mol), 0.56 g of methyl 11-bromoundecanoate
(2.0 mmol), N, N-dimethylformamide 1
20 ml of the mixed solution was heated and refluxed under a nitrogen atmosphere for 3 hours. After allowing to cool, the solvent is removed under reduced pressure, and the residue is purified by a silica gel column to give 5, 10, and 10 represented by the following structural formula (IX).
As a result, 0.16 g (yield: 85.4%) of 15-tri (4-tolyl) -20- [4- (10-carbomethoxy) decylpyridyl] porphyrin and bromide were obtained. The λmax of this compound in chloroform was 422 nm, and the molar extinction coefficient was 1.46 × 10 ⁵ .

[0051]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (IX)
Using an octafluoropentanol solution, coating was performed on a polycarbonate resin substrate in the same manner as in Example 1, and then a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film is 436
nm. The reflectance of the obtained optical recording medium at 488 nm was 60%.

(C) Optical Recording Method When the above optical recording medium was irradiated with an argon laser beam having a center wavelength of 488 nm, good recording pits could be formed.

Example 5 (a) Synthesis of porphyrin compound A solution of 10.7 g (100 mmol) of nicotinaldehyde in 350 ml of propionic acid was stirred and refluxed, and 6.71 g (100 mmol) of pyrrole was slowly added dropwise. 1
After refluxing for an hour, the solution is left to cool, and the precipitated crystals are collected by filtration and purified by an alumina column to give 5,1,1 represented by the following structural formula (X).
1.85 g (yield 12.0%) of 0,15,20-tetra (3-pyridyl) porphyrin was obtained. The λmax of this compound in chloroform was 418 nm and the molar extinction coefficient was 4.46 × 10 ⁵ .

[0055]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (X)
Using an octafluoropentanol solution, coating was performed on a polycarbonate resin substrate in the same manner as in Example 1, and then a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film is 431
nm. The reflectance of the obtained optical recording medium at 488 nm was 55%.

(C) Optical Recording Method When the above optical recording medium was irradiated with argon laser light having a center wavelength of 488 nm, good recording pits could be formed.

Example 6 (a) Synthesis of porphyrin compound 8.14 g (76 mmol) of isonicotinaldehyde,
A solution of 9.0 g (76 mmol) of p-tolualdehyde in 500 ml of propionic acid was stirred and refluxed to obtain pyrrole.
1 g (150 mmol) was slowly added dropwise. After refluxing for 1 hour, the solution is left to cool, and the precipitated crystals are collected by filtration and purified by an alumina column. The resulting crystals are 5,10-di (4-tolyl) -15,20-di (4- 1.38 g (yield 5.7%) of 5,15-di (4-tolyl) -10,20-di (4-pyridyl) porphyrin represented by (pyridyl) porphyrin and (XII) were obtained. The λmax of this compound in chloroform was 419 nm and the molar extinction coefficient was 4.54 × 10 ⁵ .

[0059]

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(B) Production of Recording Medium A 1% by weight octafluoropentanol solution of a porphyrin compound (mixture) represented by the structural formulas (XI) and (XII) was used on a polycarbonate resin substrate in the same manner as in Example 1. After coating, a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film was 430 nm. The reflectance of the obtained optical recording medium at 488 nm was 56%.

(C) Optical Recording Method When the above-mentioned optical recording medium was irradiated with argon laser light having a center wavelength of 488 nm, good recording pits could be formed.

Example 7 (a) Synthesis of porphyrin compound 4.07 g (38 mmol) of nicotinaldehyde, p-
A solution of 13.5 g (112 mmol) of tolualdehyde in 500 ml of propionic acid was stirred and refluxed to obtain pyrrole.
1 g (150 mmol) was slowly added dropwise. After refluxing for 1 hour, the solution is left to cool, and the precipitated crystals are collected by filtration and purified by a silica gel column to give 5,1,1 having the following structural formula (XIII).
0.79 g (3.2% yield) of 0,15-tri (4-tolyl) -20- (3-pyridyl) porphyrin was obtained. Next, 0.20 g of compound (XIII) (0.3 mmol
l), 4.06 g of n-octadecyl bromide (12 mm
ol) and 180 ml of a mixture of N, N-dimethylformamide were heated and refluxed for 3 hours under a nitrogen atmosphere. After allowing to cool, the solvent is removed under reduced pressure, and the residue is purified by a silica gel column to give 5,10,15-tri (4-tolyl) -20- [3-N- (n-octadecyl) represented by the following structural formula (XIV). ) Pyridyl] porphyrin, 0.18 g (60.5% yield) of bromide was obtained. The λmax of this compound in chloroform was 426 nm, and the molar extinction coefficient was 2.
It was 40 × 10 ⁵ .

[0063]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (XIV)
An octafluoropentanol solution was used and applied on a polycarbonate resin substrate in the same manner as in Example 1, and then a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film is 43
It was 3 nm. The reflectance of the obtained optical recording medium at 488 nm was 65%.

(C) Optical Recording Method When the above-mentioned optical recording medium was irradiated with argon laser light having a center wavelength of 488 nm, good recording pits could be formed.

Example 8 (a) Synthesis of porphyrin compound 4.07 g (38 mmol) of picolinaldehyde, p-
A solution of 13.5 g (112 mmol) of tolualdehyde in 500 ml of propionic acid was stirred and refluxed to obtain pyrrole.
1 g (150 mmol) was slowly added dropwise. After refluxing for 1 hour, the solution is left to cool, and the precipitated crystals are collected by filtration and purified with a silica gel column to give 5, 10, and 10 represented by the following structural formula (XV).
0.88 g (3.6% yield) of 15-tri (4-tolyl) -20- (2-pyridyl) porphyrin was obtained. Next, 0.10 g (0.15 mmol) of compound (XV), n-
2.03 g (6 mmol) of octadecyl bromide, N,
A mixed solution of 90 ml of N-dimethylformamide was heated and refluxed under a nitrogen atmosphere for 3 hours. After allowing to cool, the solvent is removed under reduced pressure, and the residue is purified by a silica gel column to give 5,10,15-tri (4-tolyl) represented by the following structural formula (XVI).
-20- [2-N- (n-octadecyl) pyridyl] porphyrin, 0.075 g of bromide (49.8% yield)
was gotten. The λmax of this compound in chloroform was 424 nm, and the molar extinction coefficient was 2.69 × 10 ⁵ .

[0067]

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(B) Production of recording medium 1% by weight of the porphyrin compound represented by the structural formula (XVI)
An octafluoropentanol solution was used and applied on a polycarbonate resin substrate in the same manner as in Example 1, and then a reflective layer and a protective layer were formed. The maximum absorption wavelength of the coating film is 43
It was 0 nm. The reflectance of the obtained optical recording medium at 488 nm was 64%.

(C) Optical Recording Method When the above-mentioned optical recording medium was irradiated with an argon laser beam having a center wavelength of 488 nm, good recording pits could be formed.

Example 9 (a) Synthesis of porphyrin compound 4.07 g (38 mmol) of isonicotinaldehyde,
12.6 g of 2-thiophene carboxaldehyde (11
A solution of 2 mmol) in propionic acid in 500 ml was stirred and refluxed, and 10.1 g (150 mmol) of pyrrole was slowly added dropwise. After refluxing for 1 hour, the solution is left to cool and the precipitated crystals are filtered off and purified by a silica gel column to give the following structural formula (XVI
5,10,15-tri (2-thienyl) represented by I)
0.37 g (yield 1.5%) of -20- (4-pyridyl) porphyrin was obtained. Next, compound (XVII) 0.10
g (0.16 mmol), a mixed solution of 0.53 g (1.6 mmol) of n-octadecyl bromide and 90 ml of N, N-dimethylformamide were heated and refluxed under a nitrogen atmosphere for 3 hours. After allowing to cool, the solvent was removed under reduced pressure, and the residue was purified by a silica gel column. As a result, 5,10,15-tri (2-thienyl) -20- [4-
[N- (n-octadecyl) pyridyl] porphyrin and 0.049 g (32.0% yield) of bromide were obtained. The λmax of this compound in chloroform was 430 nm and the molar extinction coefficient was 1.65 × 10 ⁵ .

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(B) Production of recording medium A 1% by weight solution of a porphyrin compound represented by the structural formula (XVIII) in octafluoropentanol was applied to a polycarbonate resin substrate in the same manner as in Example 1; A protective layer was formed. The maximum absorption wavelength of the coating film is 43
It was 9 nm. The reflectance of the obtained optical recording medium at 488 nm was 62%.

(C) Optical Recording Method When the above-mentioned optical recording medium was irradiated with argon laser light having a center wavelength of 488 nm, good recording pits could be formed.

Examples 10-52 The compounds shown in Table 1 were synthesized in the same manner as in Example 1.
The maximum absorption wavelength and the molecular absorption coefficient (ε) are shown. Also,
Using these porphyrin-based compounds, they were applied on a substrate in the same manner as in Example 1 to produce an optical recording medium. Table 1 shows the maximum absorption wavelength of the coating film. When recording was performed on the obtained optical recording medium using an argon laser having a center wavelength of 488 nm, good recording pits could be formed in each case.

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[Table 1]

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[Table 2]

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[Table 3]

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[Table 4]

The abbreviations in Table 1 are as follows.

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[0081]

According to the optical recording medium using the porphyrin compound of the present invention, an inexpensive, high-density recording medium having excellent light resistance and heat resistance is provided, and is extremely useful industrially.

[Brief description of the drawings]

FIG. 1 is an absorption spectrum diagram of a porphyrin compound obtained in Example 1 in a chloroform solution.

FIG. 2 is an absorption spectrum diagram of a coating film of a porphyrin compound obtained in Example 1 on a polycarbonate substrate.

FIG. 3 is an absorption spectrum diagram of a porphyrin compound obtained in Example 2 in a chloroform solution.

FIG. 4 is an absorption spectrum diagram of a coating film of a porphyrin compound obtained in Example 2 on a polycarbonate substrate.

FIG. 5 is an absorption spectrum diagram of a porphyrin compound obtained in Example 3 in a chloroform solution.

FIG. 6 is an absorption spectrum diagram of a coating film of a porphyrin compound obtained in Example 3 on a polycarbonate substrate.

Claims (3)

[Claims] 1. An optical recording medium having a recording layer on which information can be written and / or read by a laser on a substrate, wherein the recording layer has the following general formula (I): (Wherein, R ^{1 to} R ⁴ each independently represent an aromatic ring or a heterocyclic ring which may have a substituent, and X ^{1 to} X ⁸
Each independently represents a hydrogen atom, a halogen atom or a nitro group, and M represents a hydrogen atom or a metal. An optical recording medium comprising the porphyrin compound represented by the formula (1). 2. In the general formula (I), R¹~ R^FourBut,
Benzene which may have a substituent each independently
A ring, a pyridine ring or a thiophene ring; ¹~ X
⁸Are each independently a hydrogen atom, a halogen atom or
2. The optical recording according to claim 1, which is a nitro group.
Recording medium. 3. The optical recording medium according to claim 1, wherein the writing and reading laser wavelengths are both 350 nm to 530 nm.