JPH07166082A - Phthalocyanine compound and optical recording medium containing the same - Google Patents

Abstract

PURPOSE:To obtain a colorant for use in optical recording media which retains high sensitivity even in high-speed or high-density recording to attain satisfactory recording properties and which is excellent in long-term stability and light resistance by obtaining a specific phthalocyanine compound. CONSTITUTION:One to four phthalonitrile compounds represented by formula I (where R and R' each is a 1-15C saturated hydrocarbon group or a 2-15C unsaturated hydrocarbon group) are mixed with one to four phthalonitrile compounds represented by formula II (wherein R and R' are as defined above and X is a halogen). This mixture is reacted with a Pd compound with heating either in an alcohol in the presence of, e.g. 1, 8-diazabicyclo[5, 4, 0]undecene (DBU) or in a high-boiling solvent such as chloronaphthalene. Thus, this compound is obtained, which is represented by formula III (wherein R<1> to R<8> each is a 1-15C (un)substituted saturated hydrocarbon group or a 2-15C (un)substituted unsaturated hydrocarbon group and X<1> to X<8> each is a halogen or H). One or two layers of one to three compounds comprising this compound are formed on a transparent substrate by coating or vapor deposition to obtain this medium.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a compound useful as a near-infrared absorber that plays an important role in optoelectronics related to information recording, display sensors, protective glasses, etc., and a compound formed in the recording layer. Optical recording medium such as an optical disc and an optical card.

[0002]

2. Description of the Related Art A technique for using a phthalocyanine dye, particularly an alkoxy-substituted phthalocyanine, in a recording layer of a recording medium such as an optical disk and an optical card is disclosed in JP-A-61-154888 (EP).
186404), No. 61-197280, No. 61-246091, and No. 6
2-39286 (USP4769307), 63-37991, 63-
It is widely known from Japanese Patent No. 39388. It has been difficult to say that the optical recording medium using the phthalocyanine dye disclosed in these patents has sufficient performance in terms of sensitivity and recording characteristics. Particularly, in JP-A-61-197280, MPc (OR) _n (Y) _16-n (M: metal,
OR: alkoxy group, Y: hydrogen or halogen atom, P
c: Phthalocyanine ring, n = 5 to 16), but as the metal, Cu, Ni, Co, Fe, I
It is preferable because attention is paid to n, Al, Pt, V, hydrogen, etc., and effects and examples of Pd are not described. Further, it does not particularly mention the substitution position of the alkoxy group with respect to the phthalocyanine ring.

The improvement of the above is disclosed in Japanese Patent Laid-Open No. 3-62878.
(USP5124067), the improved compound also has a large error at the time of high-speed recording and high-density recording by a laser beam and is not yet practically sufficient. Here again, 8 in the molecule
As for the central metal of the metal phthalocyanine having one alkoxy group, the effect and the example that the Pd is good is not described.

[0004]

Writing to and reading from an optical recording medium is generally performed by a laser of 600 to 900 nm.
Since light is used, it is necessary to control the absorption coefficient and the refractive index of the recording material in the vicinity of the laser oscillation wavelength used and to form pits with high accuracy during writing. This is especially important in high-speed recording and high-density recording which have been recently desired. In addition, it is essential to have excellent durability.

In order to satisfy the above requirements, the structural stability is high, the refractive index is high for light in the vicinity of the laser oscillation wavelength,
It is necessary to develop a dye for an optical recording medium that has good decomposition characteristics and high sensitivity. However, conventionally developed dyes for optical recording media have drawbacks in that they have drawbacks in sensitivity (C / N ratio) and recording characteristics (jitter, deviation) particularly when used in recording media at high speed recording and high density recording. there were.

Therefore, an object of the present invention is to provide an optical recording medium which improves the above-mentioned drawbacks, has high sensitivity even at high speed recording and high density recording, has good recording characteristics, and is excellent in long-term stability and light resistance. To supply the dye.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found a novel phthalocyanine compound represented by the following general formula (I) and completed the present invention. It was

That is, the present invention provides the following general formula (I)

[0009]

[Chemical 2] [In the formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently (a) a substituted or unsubstituted saturated group having 1 to 15 carbon atoms. Hydrocarbon group or (b) C2-C2
15 represents a substituted or unsubstituted unsaturated hydrocarbon group. X
^{1, X 2, X 3,} X 4, X 5, X 6, X 7 and X ⁸ represents a halogen atom or a hydrogen atom. However, X ¹ , X ² , X ³ ,
At least two of X ⁴ , X ⁵ , X ⁶ , X ⁷ and X ⁸ are halogen atoms. ] The phthalocyanine compound shown by these, and the optical recording medium formed by containing it in a recording layer.

Particularly in the general formula (I), R¹, R², R
³, R^Four, R^Five, R⁶, R⁷And R⁸At least two of
The top is a branched saturated or unsaturated hydrocarbon group.
And X ¹, X², X³, X^Four, X^Five, X⁶, X⁷And X⁸Is chlorine
Or be bromine, X¹, X², X³, X^Four, X^Five，
X⁶, X⁷And X⁸Are the same halogen atom, R¹When
R ², R³And R^Four, R^FiveAnd R⁶And R⁷And R⁸To the combination of
, Each with a different molecular formula or different geometric
A saturated or unsaturated hydrocarbon group represented by R, ¹，
R², R³, R^Four, R^Five, R⁶, R⁷And R⁸Of hydrocarbon group
The total number of carbon atoms is 24 to 64, and further R¹When
R², R³And R^Four, R^FiveAnd R⁶And R⁷And R⁸To the combination of
In addition, the sum of carbon numbers of the respective hydrocarbon groups is 6 to 16.
Is preferred.

The substituent of the substituted saturated or unsaturated hydrocarbon group represented by the general formula (I) includes an alkyloxy group, an aryloxy group, an acyl group, a hydroxy group,
There are amino groups, alkylthio groups, arylthio groups, and aryl groups. The unsaturated hydrocarbon group represented by formula (I) is an alkenyl group, an alkynyl group or an aryl group.

The phthalocyanine compound of the present invention is 700
It has a sharp absorption at ~ 800 nm, a high molecular extinction coefficient of 150,000 or more, and excellent long-term stability and light resistance. It is suitable as a recording material for recording media (optical disks, optical cards, etc.). The mechanism has not been clarified yet, but it is being studied at present. In particular, the substitution of eight appropriate alkoxy groups at the α-position of the phthalocyanine ring controlled the steric hindrance and melting point in the molecule, and the central metal was changed to Pd. It is considered that the fact that the appropriate absorption wavelength / absorption coefficient is obtained by doing so contributes to the improvement of the sensitivity at the time of recording and is effective in reducing the error of the formed signal. That is, the decomposition / melting of the dye was controlled during optical recording to form highly accurate pits, the damage to the resin substrate of the recording medium was reduced, and in the case of a recording medium having a reflective layer, the recording layer and the reflective layer The improved adhesion to the metal layer, which is a layer, may be mentioned. Further, by using Pd as the central metal, it has excellent heat, light and chemical stability.

The characteristics of the phthalocyanine compound of the present invention are as follows:
The α-position of the phthalocyanine ring is substituted with eight saturated hydrocarbon groups or unsaturated hydrocarbon groups via oxygen atoms, the β-position is substituted with two or more halogen atoms, and the central metal is Pd. .

The preferred embodiments of the present invention will be described in detail below.

In the general formula (I), a specific example of the substituent represented by OR is a saturated hydrocarbon oxy group having 1 to 15 carbon atoms or an unsaturated hydrocarbon oxy group having 2 to 15 carbon atoms. Considering the availability and the melting point of the entire phthalocyanine molecule, a substituted or unsubstituted saturated hydrocarbon oxy group having up to 12 carbon atoms or an unsaturated hydrocarbon oxy group is preferable.

For example, examples of the unsubstituted saturated hydrocarbon oxy group include methoxy group, ethoxy group, n-propyloxy group, iso-propyloxy group, iso-butyloxy group, sec-
Butyloxy group, t-butyloxy group, n-pentyloxy group, iso-pentyloxy group, neo-pentyloxy group, 2-
Methylbutyl-3-oxy group, n-hexyloxy group, cyclo
-Hexyloxy group, 2-methylpentyl-1-oxy group, 2-
Methylpentyl-4-oxy group, 2-methylpentyl-5-oxy group, 2-methylpentyl-3-oxy group, 3-methylpentyl-4-oxy group, 3-methylpentyl-5-oxy group, n- Heptyloxy group, 2-methylhexyl-5-oxy group, 2-methylhexyl-6-oxy group, 2,4-dimethylpentyl-3-oxy group, 2-methylhexyl-3-oxy group, heptyl-4- Oxy group, n-octyloxy group, 2-ethylhexyl-1-oxy group, 2,5-dimethylhexyl-3-oxy group, 2,4-dimethylhexyl-3-oxy group, 2,2,4-trimethylpentyl group -3-
Oxy group, n-nonyloxy group, 3,5-dimethylheptyl-4
-Oxy group, 2,6-dimethylheptyl-3-oxy group, 2,4-dimethylheptyl-3-oxy group, 3,5,5-trimethylhexyl-1-oxy group, n-dodecyloxy group, 2, 2,5,5-Tetramethylhexyl-3-oxy group, 1-cyclo-pentyl-2,2-dimethylpropyl-1-oxy group, 1-cyclo-hexyl-2,2-dimethylpropyl-1-oxy group Etc.

Examples of the substituted saturated hydrocarbon oxy group include alkoxymethoxy groups such as methoxyethoxy group, ethoxyethoxy group, propoxyethoxy group, butoxyethoxy group, γ-methoxypropyloxy group, γ-ethoxypropyloxy group, methoxyethoxy group. Alkoxyalkoxyalkoxy groups such as ethoxy group, butyloxyethoxyethoxy group, dimethylaminoethoxy group, 2-amino-2-
Aminoalkoxy group such as methylhexyl-3-oxy group,

Aralkyl such as benzyloxy group, 4-tert-butylbenzyloxy group, 4-cyclo-hexylbenzyloxy group, phenylethyloxy group, naphthylmethyloxy group, 3-benzyl-3-methylbutyl-2-oxy group Oxy group, 2-hydroxyethyl-1-oxy group, 2-hydroxy-3-
Hydroxyalkoxy group such as phenoxypropyl-1-oxy group, acyloxyalkoxy group such as acetoxyethyloxy group, acetoxyethoxyethyloxy group, 4-te
rt-Butylphenoxymethoxy group, aryloxyalkoxy group such as phenoxyethoxy group, methylthioethoxy group, ethylthioethoxy group, alkylthioalkoxy group such as n-propylthiopropoxy group, phenylthiomethoxy group, naphthylthioethoxy group, 4 Examples of the arylthioalkoxy group include a -tert-butylphenylthioethoxy group and a methoxyphenylthiomethoxy group.

Examples of the substituted or unsubstituted unsaturated hydrocarbon oxy group include ethenyloxy group, 2-propenyl-1-oxy group, 1-butenyl-3-oxy group, 2-butenyl-1-oxy group, 3- Butenyl-1-oxy group, 3-butenyl-2-oxy group,
1-hydroxy-2-butenyl-4-oxy group, 2-pentenyl-1
-Oxy group, 3-pentenyl-2-oxy group, 1-pentenyl-3
-Oxy group, 1,4-pentadienyl-3-oxy group, 1-hexenyl-3-oxy group, 2-hexenyl-1-oxy group, 2-hexenyl-4-oxy group, 3-hexenyl-2-oxy group , 4-hexenyl-3-oxy group, 5-hexenyl-2-oxy group, 5-hexenyl-1-oxy group, 3-hexenyl-1-oxy group, 4-hexenyl-1-oxy group, 2,4- Hexadienyl-1-oxy group, 1,
4-hexadienyl-3-oxy group, 1,5-hexadienyl-3-
Oxy group, 1-hydroxy-2,4-hexadienyl-6-oxy group, 2,5-hexadienyl-1-oxy group, 1,3-hexadienyl-5-oxy group, 1-heptenyl-3-oxy group, 2 -Heptenyl-4-oxy group, 3-heptenyl-5-oxy group, 1,4-heptadienyl-3-oxy group, 1,5-heptadienyl-4-oxy group, 1,5-heptadienyl-3-oxy group, 2,5-heptadienyl-4-oxy group, 1-octenyl-3-oxy group, 2-octenyl-4-oxy group, 1-octenyl-4-oxy group, 1-nonenyl-3-oxy group,

4-dimethylamino-1-butenyl-3-oxy group, 4-methylthio-1-butenyl-3-oxy group, 4-acetoxy-1-butenyl-3-oxy group, 4-phenylthio-1-butenyl -3-oxy group, 1-cyclopentyl-2-methyl-2-propenyl-1-oxy group, 1-cyclohexyl-2-methyl-2-propenyl-1-oxy group, 2-methyl-2-butenyl-1- Oxy group, 3-methyl-2-butenyl-1-oxy group, 2-methyl-3-butenyl-2-oxy group, 3-methyl-3-butenyl-2-oxy group, 3-methyl-2-butenyl- 1-oxy group, 2-methyl-3-butenyl-1-oxy group, 3-methyl-3-butenyl-1-oxy group, 2,3-dimethyl-3-butenyl-2-oxy group, 2-methyl- 1
-Pentenyl-3-oxy group, 3-methyl-1-pentenyl-3-oxy group, 4-methyl-3-pentenyl-2-oxy group, 4-methyl
-1-Pentenyl-3-oxy group, 3-methyl-4-pentenyl-3-
Oxy group, 2-methyl-4-pentenyl-3-oxy group, 3-methyl-4-pentenyl-2-oxy group, 4-methyl-4-pentenyl-
2-oxy group, 2-methyl-4-pentenyl-2-oxy group, 2,4-
Dimethyl-1-pentenyl-3-oxy group, 2,3-dimethyl-1-
Pentenyl-3-oxy group, 2,4-dimethyl-1,4-pentadienyl-3-oxy group, 2,4,4-trimethyl-1-pentenyl-3-
Oxy group, 4-methyl-4-hexenyl-3-oxy group, 2-methyl-1-hexenyl-3-oxy group, 2-methyl-4-hexenyl-
3-oxy group, 3-methyl-3-hexenyl-2-oxy group, 4-methyl-4-hexenyl-2-oxy group, 5-methyl-5-hexenyl-2-oxy group, 5-methyl-5- Hexenyl-3-oxy group, 2
-Methyl-5-hexenyl-3-oxy group, 2,5-dimethyl-5-hexenyl-4-oxy group, 2,5-dimethyl-5-hexenyl-3-
Oxy group, 2,2-dimethyl-5-hexenyl-3-oxy group, 2-
Methyl-1,5-hexadienyl-3-oxy group, 2-methyl-1,5
-Hexadienyl-4-oxy group, 5-methyl-1,5-hexadienyl-3-oxy group, 2,5-dimethyl-1,5-hexadienyl
-3-oxy group, 2,2-dimethyl-5-hexenyl-4-oxy group, 2,3,4-trimethyl-4-hexenyl-3-oxy group, 2-methyl-1-heptenyl-3-oxy group , 5-methyl-1-heptenyl-3-oxy group, 4-methyl-4-heptenyl-3-oxy group, 6
-Methyl-5-heptenyl-2-oxy group, 5-methyl-1-heptenyl-4-oxy group, 6-methyl-6-heptenyl-3-oxy group, 2-methyl-1,5-heptadienyl-4- Oxy group, 2,5-dimethyl-1-heptenyl-3-oxy group, 3,5-dimethyl-1,6-
Heptadienyl-4-oxy group, 2,4-dimethyl-2,6-heptadienyl-1-oxy group, 2,6-dimethyl-2,5-heptadienyl-4-oxy group, 3,5-dimethyl-1,5 -Heptadienyl-4
-Oxy group, 2-methyl-4-dimethylamino-1-butenyl-3-
Oxy group, 2-methyl-4-methylthio-1-butenyl-3-oxy group, 3-methyl-2-pentenyl-4-yn-1-oxy group, 2,6
-Dimethyl-1-nonenyl-3-yn-5-oxy group, 1-phenyl
-4-methyl-1-pentynyl-3-oxy group, 4-ethyl-1-hexynyl-3-oxy group, 2,6-dimethyl-6-heptenyl-4-yn-3-oxy group, 4-methyl- 1-pentynyl-3-oxy group, 4
Examples thereof include -tert-butylphenyloxy group, naphthyloxy group, toluyloxy group and methoxyphenyloxy group.

As a particularly preferred example, the number of carbon atoms is 11 in consideration of the melting point of the dye and the cyclization reaction to phthalocyanine.
In the following, a group having a suitable steric hindrance by appropriately branching, and a group capable of increasing the extinction coefficient per unit weight, and a group effective for improving the sensitivity when used as an optical recording medium, Is iso-butyloxy group, iso-pentyloxy group, 2-methylpentyl-1-oxy group, 2-methylpentyl-5-oxy group, 3-methylpentyl-5-oxy group, 2-methylhexyl-6-oxy group Group, 2-ethylhexyl-1-oxy group, 3,5,5-trimethylhexyl-1-oxy group, 2-methyl-
2-butenyl-1-oxy group, 3-methyl-2-butenyl-1-oxy group, 3-methyl-2-butenyl-1-oxy group, 2-methyl-3-
Butenyl-1-oxy group, 3-methyl-3-butenyl-1-oxy group, 2,4-dimethyl-2,6-heptadienyl-1-oxy group, 3
-Methyl-2-pentenyl-4-yn-1-oxy group, 4-tert-butylbenzyloxy group and the like. However, in the general formula (I)
In the combinations of OR ¹ and OR ² , OR ³ and OR ⁴ , OR ⁵ and OR ⁶ and OR ⁷ and OR ⁸ in 1 above, it is preferable that one of them is as described above.

Further, OR ¹ and OR ² , OR ³ and OR ⁴ , OR
^In the combination of ⁵ and OR ⁶ and OR ⁷ and OR ⁸ , saturated or unsaturated hydrocarbon groups having different molecular formulas or different geometric structural formulas are preferable because the solubility in the coating organic solvent is high.

Halogen includes fluorine, chlorine, bromine,
Examples include iodine.

The phthalocyanine compound represented by the general formula (I) can be synthesized by the following formula (II) or (III)

[0025]

[Chemical 3] [In the formulas (II) and (III), R and R'represent a hydrocarbon group as described in the general formula (I), and X represents a halogen atom. ] Each of the phthalonitrile compounds represented by
Diazabicyclo [5,4,0] -7-undecene (DB
U) In the presence of U, the Pd metal derivative is heated and reacted in alcohol. Alternatively, a method in which the Pd metal derivative and the Pd metal derivative are heated and reacted in a high-boiling-point solvent such as chloronaphthalene, bromonaphthalene, and trichlorobenzene can be mentioned. Examples of the Pd metal derivative include PdCl ₂ , PdBr ₂ , PdI ₂ , and Pd.
O, PdSO ₄ , (CH ₃ COO) ₂ Pd, Pd (NO ₃ )
₂ , (CF ₃ COO) ₂ Pd and the like. Note that the formula (I
A phthalocyanine compound represented by the general formula (I) can be obtained by reacting a phthalocyanine compound synthesized from I) with a halogenating agent such as thionyl chloride, sulfuryl chloride, hydrobromic acid, bromine, iodine and iodine monochloride. . In the case of the phthalocyanine compound synthesized from the formula (III),
The halogen species on the phthalocyanine ring can be replaced by reaction with the copper halide. In addition, a compound represented by the formula (II) or (III) is reacted with ammonia by using sodium methylate as a catalyst in alcohol to obtain the compound represented by the formula (IV).
Alternatively, a method in which diiminoisoindoline represented by (V) is similarly used as an intermediate and the like can be mentioned.

[0026]

[Chemical 4]

The synthesis of the compound represented by the formula (II) or (III) is generally carried out in JP-A 61-197280 and JP-A 02-27.
It can be synthesized by the method described in 9664 and JP-A-02-279665.

In the method for producing an optical recording medium using the phthalocyanine compound of the present invention, 1 to 3 compounds containing the phthalocyanine compound of the present invention are coated or vapor-deposited on a transparent substrate in one layer or two layers. There is a method, and the coating method is 20% by weight or less of the binder resin, preferably 0
%, And 1 to 3 compounds including the phthalocyanine compound of the present invention 0.05 to 20% by weight, preferably 0.5 to 20
There is a method in which it is dissolved in a solvent so as to be a weight% and applied by a spin coater. The vapor deposition method is 10 ^-5 to 1
There is a method of depositing 1 to 3 kinds of compounds including a phthalocyanine compound on a substrate at 0 ^-7 torr and 100 to 300 ° C.

The substrate may be any optically transparent resin. Examples thereof include acrylic resin, polyethylene resin, vinyl chloride resin, vinylidene chloride resin, polycarbonate resin, polyolefin copolymer resin, vinyl chloride copolymer resin, vinylidene chloride copolymer resin, and styrene copolymer resin. The substrate may be surface-treated with a thermosetting resin or an ultraviolet curable resin.

When manufacturing an optical recording medium (optical disk, optical card, etc.), a polyacrylate substrate or a polycarbonate substrate is used as the substrate and is applied by a spin coating method in terms of cost and handling by the user. preferable.

Due to the solvent resistance of the substrate, the solvent used for spin coating is a halogenated hydrocarbon (eg, dichloromethane, chloroform, carbon tetrachloride, tetrachloroethylene, dichlorodifluoroethane, etc.), ethers (eg, tetrahydrofuran, diethyl ether, diether). Propyl ether, dibutyl ether, dioxane, etc.), alcohols (eg, methanol, ethanol, propanol, etc.), cellosolves (eg, methyl cellosolve,
Ethyl cellosolve, etc.), hydrocarbons (eg, hexane, cyclohexane, ethylcyclohexane, cyclooctane, dimethylcyclohexane, octane, benzene, toluene, xylene, etc.), or a mixed solvent thereof is preferably used.

In order to process it as a recording medium, it is covered with a substrate as described above, or a substrate provided with two recording layers,
There is a method in which an air gap is provided so as to face each other and the substrates are bonded together, or a reflective layer (aluminum or gold) is provided on the recording layer and a protective layer of a thermosetting or photocurable resin is laminated. As a protective layer, Al ₂ O ₃ , SiO ₂ , S
iO, may be used an inorganic compound of SnO ₂ or the like.

[0033]

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

Example 1 85.3 g (0.37 mol) of 2,3-dicyano-5,6-dichlorohydroquinone represented by the following structural formula (A-1)

[0035]

[Chemical 5] 205.5 g (1.40 mol) of potassium carbonate and 300 ml of N, N-dimethylacetamide are placed in a vessel equipped with a stirrer, a reflux condenser and a nitrogen introducing tube, and stirred under aeration of nitrogen. After heating to 60 ° C. and stirring for 30 minutes, 124.0 g (0.82 mol) of iso-amyl bromide was added at 60 ° C., followed by heating and stirring at 80 ° C. for 20 hours.
Next, this was discharged into 1.5 liters of water, extracted and concentrated with ethyl acetate, and then subjected to column purification (silica gel 500).
g, solvent; hexane: ethyl acetate = 5: 2) to obtain 103.0 g (yield 75%) of an alkoxyphthalonitrile compound represented by the following structural formula (A-2).

[0036]

[Chemical 6]

The result of purity analysis by liquid chromatography was 99.2%. The results of elemental analysis are as follows.

[0038]

Next, in a container equipped with a stirrer, a reflux condenser, and a nitrogen inlet tube, 11.1 g (0.
03 mol), 4.56 g (0.03 mol) of DBU and n
40 ml of amyl alcohol was charged and the temperature was raised to 100 ° C under a nitrogen atmosphere. Next, at the same temperature, 1.35 g (0.0075 mol) of palladium chloride was added,
The reaction was carried out at -100 ° C for 20 hours. After completion of the reaction, the mixture was cooled and the insoluble matter was filtered off. After the filtrate was concentrated under reduced pressure to recover the solvent, column purification (silica gel 200 g, solvent; toluene: hexane = 1: 9) was performed to obtain a desired phthalocyanine palladium compound having 8 hydrocarbon oxy groups at the α-position. Green crystals were obtained. Yield 7.2 g (yield 61
%)Met. The result of purity measurement by high-performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 720.5 nm ε _g = 1.5 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

A solution of the above phthalocyanine compound in n-octane (10 g / l) was formed into a spiral groove (pitch 1.
6 μm, groove width of 0.6 μm, groove depth of 0.18 μm), and a spin coat film was formed at 500 to 1000 rpm on a polycarbonate substrate for CD-R having an outer diameter of 120 mm and a thickness of 1.2 mm. A 30 nm gold layer is sputter-deposited thereon to form a reflective layer, and then a protective layer is formed by overcoating with a photo-curing polyacrylic resin and then photo-curing to form a CD-R.
A mold medium was prepared. When an EFM signal was written on this medium at a linear velocity of 1.4 m / s and a power of 6.0 mW using a semiconductor laser having a wavelength of 780 nm, the error rate was less than 0.2%. Light 63 ℃, 200
There was no change in the durability test of time.

Example 2 170.6 g (0.74 mol) of the compound represented by (A-1), 205.5 g (1.40 mol) of potassium carbonate and
600 ml of N, N-dimethylformamide is charged into a vessel equipped with a stirrer, a reflux condenser and a nitrogen introduction tube, and stirred under aeration of nitrogen. After heating to 60 ℃ and stirring for 30 minutes, iso-
Butyl bromide (60) was added to 109.6 g (0.80 mol).
The mixture was added at 0 ° C, then heated to 80 ° C and stirred for 20 hours. Next, this was discharged into 3.0 liters of water, extracted and concentrated with ethyl acetate, and then column purified (silica gel 1 kg, solvent; hexane: ethyl acetate = 5: 2), and the following structural formula (A-3 172.0 g (yield 81%) of the alkoxyphthalonitrile compound represented by

[0043]

[Chemical 7]

The result of purity analysis by liquid chromatography was 99.1%. The results of elemental analysis are as follows.

[0045]

95.0 g of the compound represented by (A-3)
(0.33 mol) and 92.0 g of potassium carbonate (0.63 mol)
Mol) and 300 ml of N, N-dimethylacetamide are charged into a vessel equipped with a stirrer, a reflux condenser and a nitrogen introducing tube, and stirred under aeration of nitrogen. After heating to 60 ° C. and stirring for 30 minutes, 61.7 g (0.37 g of n-hexyl bromide)
Mol) at 60 ° C., then the temperature is raised to 80 ° C. for 20
The mixture was heated and stirred for an hour. Next, this was discharged into 1.5 liters of water, extracted and concentrated with ethyl acetate, and then purified by column (500 g of silica gel, solvent; hexane: ethyl acetate =
5: 2) to obtain 103.0 g (yield 84%) of an alkoxyphthalonitrile compound represented by the following structural formula (A-4).

[0047]

[Chemical 8]

The result of purity analysis by liquid chromatography was 99.3%. The results of elemental analysis are as follows.

[0049]

Next, 11.1 g of compound (A-4) (0.1%) was added to a container equipped with a stirrer, a reflux condenser and a nitrogen inlet tube.
03 mol), 4.56 g (0.03 mol) of DBU and n
40 ml of amyl alcohol was charged and the temperature was raised to 100 ° C under a nitrogen atmosphere. Next, at the same temperature, 1.35 g (0.0075 mol) of palladium chloride was added,
The reaction was carried out at -100 ° C for 20 hours. After completion of the reaction, the mixture was cooled and the insoluble matter was filtered off. After the filtrate was concentrated under reduced pressure to recover the solvent, column purification (silica gel 200 g, solvent; toluene: hexane = 1: 9) was performed to obtain a desired phthalocyanine palladium compound having 8 hydrocarbon oxy groups at the α-position. Green crystals were obtained. The yield is 7.0 g (yield 59
%)Met. The result of purity measurement by high-performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 722.5 nm ε _g = 1.5 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Dibutyl ether of the above phthalocyanine compound
A tellurium solution (10 g / l) was applied onto a polycarbonate substrate for CD-R by a spin coater in the same manner as in Example 1, gold was sputter-deposited on the substrate, and then a protective layer was formed using a UV curable resin. , A CD-R type medium was produced.
When an EFM signal was written on this medium at a linear velocity of 1.4 m / s with a power of 6.0 mW using a semiconductor laser of 780 nm, the error rate was less than 0.2%, and the error rate was less than 0.2%.
There was no change even after performing reproduction 1 million times with reproduction light of 5 mW. Recording / reproduction was not affected even after 1000 hours under the condition of 80 ° C./85%.

Example 3 In the same manner as in Example 2, the compound of formula (A-3) 95.
0 g (0.33 mol) and potassium carbonate 92.0 g (0.
(63 mol) and 300 ml of N, N-dimethylacetamide are placed in a vessel equipped with a stirrer, a reflux condenser and a nitrogen inlet tube, and stirred under aeration of nitrogen. After heating to 60 ° C. and stirring for 30 minutes, 55.9 g of iso-amyl bromide (0.
(37 mol) was added at 60 ° C., the temperature was raised and the mixture was heated with stirring at 80 ° C. for 20 hours. Next, this was discharged into 1.5 liters of water, extracted and concentrated with ethyl acetate, and then column purified (silica gel 500 g, solvent; hexane: ethyl acetate = 5: 2), and the following structural formula (A-5 97.0 g (yield 82%) of the alkoxyphthalonitrile compound represented by
Got

[0054]

[Chemical 9]

The result of purity analysis by liquid chromatography was 99.4%. The results of elemental analysis are as follows.

[0056]

Next, in a container equipped with a stirrer, a reflux condenser, and a nitrogen inlet tube, 10.7 g of compound (A-5) (0.
03 mol), 4.56 g (0.03 mol) of DBU and n
40 ml of amyl alcohol was charged and the temperature was raised to 100 ° C under a nitrogen atmosphere. Next, at the same temperature, 1.35 g (0.0075 mol) of palladium chloride was added,
The reaction was carried out at -100 ° C for 20 hours. After completion of the reaction, the mixture was cooled and the insoluble matter was filtered off. After the filtrate was concentrated under reduced pressure to recover the solvent, column purification (silica gel 200 g, solvent; toluene: hexane = 1: 9) was performed to obtain a desired phthalocyanine palladium compound having 8 hydrocarbon oxy groups at the α-position. Green crystals were obtained. Yield 7.2g (63% yield)
%)Met. The result of purity measurement by high-performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 722.5 nm ε _g = 1.6 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

10 g of the above phthalocyanine compound was dissolved in 500 ml of a mixed solvent of 3: 1 (volume ratio) of dibutyl ether and diisopropyl ether, and a spin coater was used to coat a polycarbonate optical card substrate with a thickness of 100 nm.
Then, a protective layer was formed on the coated surface by using a UV curable resin to prepare an optical card. 780n on this medium
When recorded with a semiconductor laser beam of m, linear velocity of 2 m / s, and 4 mW, the CN ratio was 61 dB. Also, linear velocity 2
Reproduction was possible with a laser beam of m / s, 0.8 mW, and when the reproduction light stability was investigated, reproduction was possible 10 ⁵ times. Furthermore, this optical card also had good storage stability.

Example 4 The same operation as in Example 1 was carried out except that 158.4 g of 2-ethylhexyl bromide was used instead of 124.0 g of iso-amyl bromide, and the alkoxyphthalonitrile represented by the following structural formula (A-6) was obtained. 122.5 g of compound (yield 7
3%) was obtained.

[0061]

[Chemical 10]

The result of purity analysis by liquid chromatography was 99.2%. The results of elemental analysis are as follows.

[0063]

0.58 g (0.025 mol) of metallic sodium was added to 100 ml of dehydrated methanol to completely dissolve it, and then 22.7 g (0.05 mol) of the compound (A-6) was added at 50-60 ° C. A heating reaction was performed while blowing ammonia gas for about 10 hours. After distilling methanol off from the reaction solution, 200 ml of toluene was added, and then the toluene layer was washed with water. After further concentrating this under reduced pressure, n-
By carrying out recrystallization in hexane, the following structural formula (A-
Diiminoisoindoline compound 21.4 represented by 7)
g (yield 91%) was obtained.

[0065]

[Chemical 11] The result of the purity analysis by liquid chromatography is 99.0.
%Met. The results of elemental analysis are as follows.

[0066]

Next, 14.1 g of compound (A-7) (0.1%) was added to a container equipped with a stirrer, a reflux condenser and a nitrogen inlet tube.
03 mol), DBU 2.28 g (0.015 mol) and n-octanol 40 ml were charged, and under a nitrogen atmosphere,
The temperature was raised to 190 ° C. Next, at the same temperature, 1.35 g (0.0075 mol) of palladium chloride was added, and 185-
The reaction was carried out at 195 ° C for 4 hours. After completion of the reaction, the mixture was cooled to room temperature, discharged into 1 liter of methanol, and the precipitate was filtered. The precipitate was subjected to column purification (200 g of silica gel, solvent; toluene: hexane = 1: 9) to obtain the target α
A green crystal of a phthalocyanine palladium compound having 8 hydrocarbon oxy groups at the position was obtained. The yield was 6.2 g (43% yield). The result of purity measurement by high-performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 729.0 nm ε _g = 1.3 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

A solution of the above phthalocyanine compound in ethylcyclohexane (20 g / l) was applied onto a polycarbonate substrate for CD-R by a spin coater in the same manner as in Example 1, and gold was sputter-deposited thereon, followed by UV curing resin. A protective layer was formed using to prepare a CD-R type medium. The error rate when an EFM signal was written with a power of 6.0 mW at a linear velocity of 2.8 m / s using a semiconductor laser of 780 nm on this medium was less than 0.2%,
There was no change even after reproducing 1 million times with reproducing light of 0.5 mW. Recording / reproduction was not affected even after 1000 hours under the condition of 80 ° C./85%.

Example 5 A mixture of the alkoxyphthalonitrile compounds represented by the structural formulas (A-2) and (A-6) at a molar ratio of 1: 1 was added to palladium chloride in the same manner as in Example 1. By heating and reacting with, a green crystal of a desired phthalocyanine palladium compound having 8 hydrocarbon oxy groups at the α-position was obtained. The yield was 5.9 g (45% yield). In addition, it was confirmed by liquid chromatography and FD-MS spectrum measurement that five or more kinds of phthalocyanine compounds were contained (the alkoxy group portion is is
Those having different mixing ratios of o-amyloxy and 2-ethylhexyloxy are included. ). The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 725.0 nm ε _g = 1.4 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

A CD-R type medium was produced in the same manner as in Example 1 using the above phthalocyanine compound. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Example 6 2,3-Dicyano-5,6-dichlorohydroquinone 85.3 g
59.2 g of 2,3-dicyanohydroquinone represented by the following structural formula (A-8) was used as a raw material instead of

[0074]

[Chemical 12] The same operation as in Example 2 was carried out except that 154.5 g of 2-ethylhexyl bromide was used instead of 109.6 g of iso-butyl bromide, and 149.1 g of an alkoxyphthalonitrile compound represented by the following structural formula (A-9) ( Yield 74%) was obtained.

[0075]

[Chemical 13]

The result of purity analysis by liquid chromatography was 99.0%. The results of elemental analysis are as follows.

[0077]

89.9 g of the compound represented by (A-9) was used in place of 95.0 g of the compound represented by (A-3), and 40.3 g of ethyl bromide was used in place of 61.7 g of n-hexyl bromide. Other than that, the same operation as in Example 2 was performed, and 84.3 g (yield 85%) of an alkoxyphthalonitrile compound represented by the following structural formula (A-10) was obtained.
Got

[0079]

[Chemical 14]

The result of purity analysis by liquid chromatography was 99.3%. The results of elemental analysis are as follows.

[0081]

Green crystals of a phthalocyanine palladium compound (A-11) having 8 hydrocarbon oxy groups at the α-position were also synthesized in the same manner as in Example 2. The yield is 5.4 g (yield 5
5%).

[0083]

[Chemical 15] [Formula (A-11) in, OR is _{OCH 2 CH (C 2 H 5} )
OR ′ of (CH ₂ ) ₃ CH ₃ represents OC ₂ H _5, and the substitution positions of OR and OR ′ substituted on the same benzene ring may be opposite to each other. ]

The result of purity measurement by high performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 726.0 nm ε _g = 1.7 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Phthalocyanine compound (A-11) 2.0
g (1.53 mmol) of 1,1,2-trichloroethane 20
It was dissolved in ml and 15 ml of water was added. Then bromine 2.0
g (12.5 mmol) and 1,1,2-trichloroethane 3 m
The mixed solution with 1 is added dropwise at 50 to 55 ° C, and 55 to 60 ° C.
3 hours at 15% sodium sulfite aqueous solution
And washed. The organic layer was added dropwise to 150 ml of methanol, and the precipitated crystals were filtered to obtain 2.7 g of the desired phthalocyanine compound (yield 92%).

The result of purity analysis by high performance liquid chromatography was 98.9%. As a result of FD-MS measurement, most of the phthalosinin rings had eight Br substituted. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 729.5 nm ε _g = 1.2 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Using the above phthalocyanine compound, a CD-R type medium was prepared in the same manner as in Example 1. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Example 7 2.0 g (1.53) of the phthalocyanine compound (A-11)
Mmol) was dissolved in 20 ml of 1,1,2-trichloroethane and 15 ml of water was added. Next, a mixed solution of 1.0 g (6.3 mmol) of bromine and 2 ml of 1,1,2-trichloroethane was added dropwise at 50 to 55 ° C., and the mixture was reacted at 55 to 60 ° C. for 2 hours to prepare 2 g of a 15% sodium sulfite aqueous solution. And washed. The organic layer was added dropwise to 150 ml of methanol, and the precipitated crystals were filtered to obtain 2.4 g (yield 95%) of the objective phthalocyanine palladium compound in which four bromine atoms were substituted.

The result of purity analysis by high performance liquid chromatography was 98.9%. As a result of FD-MS measurement, most of the phthalosinin rings had four Br substituted. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 727.5 nm ε _g = 1.4 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Using the above phthalocyanine compound, a CD-R type medium was prepared in the same manner as in Example 1. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Example 8 2.0 g of the phthalocyanine compound obtained in Example 7
(1.23 mmol) of 1,1,2-trichloroethane 20m
It was dissolved in 1 and 15 ml of water was added. Next, a mixed solution of 0.7 g (5.04 mmol) of sulfuryl chloride and 3 ml of 1,1,2-trichloroethane was added dropwise at 55 to 55 ° C.,
The reaction was carried out at ~ 70 ° C for 1 hour. The organic layer is methanol 15
The mixture was added dropwise to 0 ml, and the precipitated crystals were filtered to obtain 1.9 g of the desired phthalocyanine compound (yield 90%).

The result of purity analysis by high performance liquid chromatography was 99.0%. As a result of FD-MS measurement, it was found that most of them had 4 phthalocinine rings Br and 4 Cl. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 727.0 nm ε _g = 1.3 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Using the above phthalocyanine compound, a CD-R type medium was prepared in the same manner as in Example 1. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Example 9 A mixture of the alkoxyphthalonitrile compounds represented by the structural formulas (A-2) and (A-10) at a molar ratio of 1: 1 was used, and palladium chloride was used in the same manner as in Experimental Example 1. By heating and reacting with, a green crystal of the target phthalocyanine palladium compound was obtained. The yield was 5.9 g (yield 5
4%).

Liquid chromatography and FD-M
It was confirmed by S spectrum measurement that four kinds of phthalocyanine compounds were contained (the number of Cl was 2, 4,
Contains 6,8 phthalocyanines. ). The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 723.0 nm ε _g = 1.6 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Using the above phthalocyanine compound, a CD-R type medium was prepared in the same manner as in Example 1. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Example 10 2.0 g of the phthalocyanine compound obtained in Example 9
(1.38 mmol) of 1,1,2-trichloroethane 20m
It was dissolved in 1 and 15 ml of water was added. Then 0.9 g of bromine
A mixed solution of (5.7 mmol) and 1,1,2-trichloroethane (2 ml) was added dropwise at 50 to 55 ° C, and the mixture was heated to 55 to 60 ° C for 2 minutes.
2.5 hours of 15% sodium sulfite aqueous solution
And washed. The organic layer was added dropwise to 150 ml of methanol, and the precipitated crystals were filtered to obtain 2.2 g (yield 92%) of the target phthalocyanine palladium compound.

The result of purity analysis by high performance liquid chromatography was 99.0%. The results of visible absorption spectrum and elemental analysis are as follows.

Visible absorption: λ _max = 725.5 nm ε _g = 1.3 × 10 ⁵ cm ² g ^-1 (solvent: toluene)

Using the above phthalocyanine compound, a CD-R type medium was prepared in the same manner as in Example 1. Using a laser with a wavelength of 780 nm for this medium, a linear velocity of 1.4 m
The error rate when the EFM signal was written at a power of 6.0 mW / s was less than 0.2%.

Examples 11 to 23 From phthalonitrile (Table 1) represented by the following general formula (VI) or phthalonitrile (Table 2) represented by the following general formula (VII) or general formulas (VI) and (VII) The phthalocyanines shown in Table 3 were synthesized by reacting 1 to 4 kinds of diiminoisoindolines derived with Pd metal derivatives. These compounds had a large extinction coefficient.

[0107]

[Chemical 16]

A dimethylcyclohexane solution (10 g / l) of each of these phthalocyanine compounds was applied to a PMMA optical card substrate with a thickness of 100 nm by a spin coater, and then a protective layer was formed on the application surface using a UV curable resin. , Optical card was made. These optical cards are 78
It is possible to record with a semiconductor laser beam of 0 nm, a linear velocity of 2 m / s and 4 mW, and the CN ratio at that time is 58 to 61.
It was dB. Further, it was possible to reproduce with a laser beam having a linear velocity of 2 m / sec and 0.8 mW, and when the reproduction light stability was examined, reproduction was possible 10 ⁵ times. Further, using each of the above phthalocyanine compounds, a CD was prepared in the same manner as in Example 1.
An R type medium was produced. 780n wavelength in these media
The error rate when an EFM signal was written with a power of 6.0 mW at a linear velocity of 1.4 m / s using a m laser was less than 0.2%. In addition, when a light resistance test was performed on these media with a xenon lamp at 50 ° C., 2
There was no change after 00 hours.

[0109]

[Table 1]

[0110]

[Table 2]

[0111]

[Table 3]

Comparative Test The performances of the optical recording medium of the light absorbing compound obtained above and the optical recording medium using the known light absorbing compound were compared. As the medium of the present invention, Examples 1, 2, 3, 6, 9,
Using the media prepared in the same manner as in Example 1 by using the compounds of 12, 15, 19, 21 and 23, the following two types of known alkoxyphthalocyanines (Compared to JP-A Nos.
A medium prepared in the same manner as in Example 1 was used by using the exemplified compound of JP 62878 (USP5124067).

Comparative Example 1:

[0114]

[Chemical 17]

Comparative Example 2:

[0116]

[Chemical 18]

Recording / reproduction was carried out at a laser wavelength of 780 nm, and recording was carried out by the following three methods. Normal recording: Information of 63 minutes is recorded at a linear velocity of 1.4 m / s (1 × speed). High-speed recording: Information of 63 minutes is recorded at a linear velocity of 5.6 m / s (4 times speed). High-density recording: Information of 74 minutes is recorded at a linear velocity of 1.2 m / s.

Incidentally, at the time of normal recording and high density recording, 6.
Recording was performed with a laser power of 0 mW and 8.0 mW during high-speed recording.

Furthermore, the recording sensitivity (C / N ratio), the jitter and the deviation are set in the CD decoder DR35, respectively.
52 (manufactured by Kenwood), LJM-1851 Jitter Meter (manufactured by Leader Electronics) and TIA-175 Time Interval Analyzer (manufactured by ADC). The evaluation results are shown in Table 4.

[0120]

[Table 4]

Evaluation Criteria Sensitivity (C / N ratio) ○: ≧ 55 dB ×: <55 dB Jitter ○: 3T pit jitter and 3T land jitter <35
ns ×: 3T pit jitter or 3T land jitter ≧ 35
ns deviation ◯: -50ns <3T and 11T deviation <50
ns ×: 3T or 11T deviation ≧ 50 ns or 3T or 11T deviation ≦ −50 ns From the results in Table 4, the effect of the present invention is clear.

[0122]

INDUSTRIAL APPLICABILITY The phthalocyanine compound of the present invention has eight alkoxy groups substituted at the α-position of the phthalocyanine ring through an oxygen atom and has at least two halogen atoms at the β-position. The metal is Pd. In the optical recording medium using this compound, decomposition of the dye during writing
Since the melting can be controlled, the sensitivity and recording characteristics are improved not only in normal recording but also in high speed recording and high density recording.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location G11B 7/24 516 7215-5D // B41M 5/26 (72) Inventor Taizo Nishimoto Sakae, Yokohama-shi, Kanagawa 1190 Kasama-cho, Kusama-ku Within Mitsui Toatsu Chemicals Co., Ltd. (72) Denmi Misawa 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Pref. 1190 Mitsui Toatsu Chemical Co., Ltd.

Claims (8)

[Claims] 1. The following general formula (I): [In the formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently (a) a substituted or unsubstituted saturated group having 1 to 15 carbon atoms. Hydrocarbon group or (b) C2-C2
15 represents a substituted or unsubstituted unsaturated hydrocarbon group. X
^{1, X 2, X 3,} X 4, X 5, X 6, X 7 and X ⁸ represents a halogen atom or a hydrogen atom. However, X ¹ , X ² , X ³ ,
At least two of X ⁴ , X ⁵ , X ⁶ , X ⁷ and X ⁸ are halogen atoms. ] The phthalocyanine compound shown by these. 2. The method according to claim 1, wherein R ¹ , R ² , R ³ and
At least two of R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are
A phthalocyanine compound having a branched saturated or unsaturated hydrocarbon group. 3. The method according to claim 1, wherein X ¹ , X ² , X ³ ,
A phthalocyanine compound in which X ⁴ , X ⁵ , X ⁶ , X ⁷ and X ⁸ are chlorine or bromine. 4. The method according to claim 3, wherein X ¹ , X ² , X ³ ,
A phthalocyanine compound in which X ⁴ , X ⁵ , X ⁶ , X ⁷ and X ⁸ are the same halogen atom. 5. The combination according to claim 1, wherein the combinations of R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ and R ⁷ and R ⁸ are each represented by different molecular formulas or different geometric structural formulas. Or a phthalocyanine compound which is an unsaturated hydrocarbon group. 6. The method according to claim 1, wherein R ¹ , R ² , R ³ and
A phthalocyanine compound in which the total number of carbon atoms of the hydrocarbon groups of R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ is 24 to 64. 7. The combination of R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ and R ⁷ and R ^{8 according to} claim 6, wherein the sum of carbon numbers of the respective hydrocarbon groups is 6 to 6. A phthalocyanine compound which is 16. 8. A method according to claim 1, 2, 3, 4, 5, 6 or 7.
An optical recording medium formed by containing the phthalocyanine compound according to the item 1 in a recording layer.