JPH0550993B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a heat mode optical recording medium, and more particularly to an optical recording medium containing a specific compound as a quencher. (Prior Art) A heat mode optical recording medium uses recording light as heat, and information is stored by melting or removing a portion of the medium using recording light such as a laser to form pits. A pit-forming type is well known in which the recording is recorded and the pits are detected with readout light to read out the recording. Various dyes or a combination of dyes and resins are used in the recording layer of such optical recording media. However, such optical recording media have the disadvantage that sensitivity and C/N ratio decrease due to repeated erasing, repeated irradiation with readout light, or long-term storage. Therefore, it has been proposed to use a dye and a quencher together in order to improve the photostability of the dye, and especially to prevent decolorization (reproduction deterioration) caused by readout light (for example, JP-A-60-162691, JP-A-60-201988). , 60−
203488, 60−257290). However, even when these quenchers are used in combination, the durability of the optical recording medium against read light or the long-term storage stability cannot be said to be sufficiently satisfactory for practical purposes. (Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide an optical recording medium that is durable against repeated irradiation with readout light and has excellent storage stability. (Means for Solving the Problems) The object of the present invention is achieved by an optical recording medium comprising a substrate supporting a dye and at least one compound represented by the following general formula [] or []. Ta. (In the formula, [Cat ₁ ] and [Cat ₂ ] represent cations necessary to neutralize the complex, M ₁ and M ₂ represent nickel, copper, cobalt, palladium, or platinum. n is 1 or 2) The present invention will be described in further detail. In the compounds represented by the above general formulas [] and [], among the cations represented by [Cat ₁ ] or [Cat ₂ ], inorganic cations include alkali metals (for example, Li, Na, K, etc.), alkali Earth metals (Mg, Ca, Ba, etc.) or NH ₄ ⁺
can be given. Examples of the organic cation include quaternary ammonium ions and quaternary phosphonium ions. Among the above cations [Cat ₁ ] and [Cat ₂ ], the following general formulas (-a), (-b),
It is represented by (-c), (-d) or (-e). In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ ,
R ⁹ , R ¹⁰ , R ¹¹ and R ¹² each represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group having 6 to 14 carbon atoms, and Z ¹ and Z ² are Represents a group of nonmetallic atoms that combine with the nitrogen or phosphorus atom in each formula to form a 5- or 6-membered ring. Examples of the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n-butyl group, iso-amyl group, n-dodecyl group, and n-octadecyl group. As an aryl group having 6 to 14 carbon atoms,
For example, phenyl group, tolyl group, α-naphthyl group, etc. can be mentioned. These alkyl or aryl groups include a cyano group, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms (for example, a methyl group, an ethyl group, an n-butyl group, an n-
octyl group, etc.), C6-C14 aryl group (e.g., phenyl group, tolyl group, α-naphthyl group, etc.), C2-C20 acyloxy group (e.g., acetoxy group, benzoyloxy group, or p-methoxybenzoyl group). oxy group, etc.),
C1-C6 alkoxy groups (e.g. methoxy, ethoxy, propoxy, butoxy, etc.), aryloxy groups (e.g. phenoxy, triloxy, etc.), aralkyl groups (e.g. benzyl, phenethyl or anisyl) ), alkoxycarbonyl groups (e.g., methoxycarbonyl group, (ethoxycarbonyl group,
n-butoxycarbonyl group, etc.), aryloxycarbonyl group (e.g., phenoxycarbonyl group, triloxycarbonyl group, etc.), acyl group (e.g., acetyl group, benzoyl group, etc.), acylamino group (e.g., acetylamino group, benzoylamino group, etc.), carbamoyl group (e.g., N-ethylcarbamoyl group, N-phenylcarbamoyl group, etc.), alkylsulfonylamino group (e.g., methylsulfonylamino group, phenylsulfonylamino group, etc.), sulfamoyl group (e.g. , N-ethylsulfamoyl group,
N-phenylsulfamoyl group, etc.), sulfonyl group, (for example, mesyl group, tosyl group, etc.), etc. may be substituted. Further, Z ¹ and Z ² are a 5-membered ring or a 6-membered ring as described above.
Represents a group of nonmetallic atoms necessary to form a membered ring. Examples of these 5- or 6-membered rings include a pyridine ring, an imidazole ring, a pyrrole ring, a 2-pyrroline ring, a pyrrolidine ring, a piperidine ring, a pyrazole ring, a pyrazoline ring, and an imidazoline ring. Examples of the cation represented by the general formula (-b) include a dodecylpyridinium group, a hexadecylpyridinium group, and a dodecylimidazolium group. As the cation represented by the general formula (-c),
Examples include N-ethyl-N-hexadecylpiperidinium group and N-ethyl-N-dodecylpyrazolidinium group. The above general formulas (-a), (-b), (-c),
Among the cations represented by (-d) and (-e), those that are particularly preferably used in the present invention are:
(-a), (-b), (-d) and (-e)
It is. The types of the cations [Cat ₁ ] and [Cat ₂ ] affect the solubility of the compounds represented by the general formulas [] and [] in organic solvents. In general, when the substituent bonded to a quaternary heteroatom is an alkyl group, the longer the chain length, the higher the solubility, and this tendency is particularly marked in the case of tetraalkyl-substituted ammonium or phosphonium, and in the case of ammonium cations, the number of carbon atoms increases. Cations with a total of 17 or more carbon atoms, and in the case of phosphonium cations, cations with a total of 4 or more carbon atoms provide high solubility. In the compounds represented by the above general formulas [] and [], the preferred order of M ₁ or M ₂ is nickel, cobalt, copper, palladium, and platinum. The metal complex of the general formula [] or [] has a three-dimensional structure with four-planar coordination. In the compound of the general formula [], it is not unambiguously determined whether the thioketone group is symmetrical or asymmetric with respect to the central metal, but it is expressed as the general formula [] for convenience in the present invention. The compounds represented by the general formulas [] and [] can be synthesized as follows. The compound of the general formula [] (n = 2) is prepared by first converting disodium-1,3-dithiol-2-thione-4,5-dithiolate obtained by reacting carbon disulfide and sodium into a zinc complex, and then adding chloride to the zinc complex. React benzoyl to form bisbenzoylthio compound. It is obtained by decomposing this with an alkali and then reacting it with a metal salt. Further, the compound of the general formula [] (n=1) can be obtained by oxidizing the complex (n=2) obtained above with a suitable oxidizing agent. The compound of the general formula [] (n=2) is first obtained by reacting carbon disulfide with sodium, disodium-1,3-dithiol-2-thione-
4,5-dithiolate is heated to about 130°C to form disodium-1,2-dithiol-3-thione-
Isomerize to 4,5-dithiolate. This is made into a zinc complex, and benzoyl chloride is reacted with this,
It is a bisbenzoylthio form. It is obtained by decomposing this with an alkali and then reacting it with a metal salt. Further, the compound of the general formula [] (n=1) can be obtained by oxidizing the complex (n=2) obtained above with a suitable oxidizing agent. The 1,3-dithiol-2-thione-4,5-dithiolate anion, which is an intermediate for obtaining the compound of general formula [] or [], is as described above.
In addition to the reduction method using Na, it can also be obtained by electrochemical reduction. Preferred examples of the compounds represented by the general formulas [] and [] are as follows, but it goes without saying that the present invention is not limited to these exemplified compounds.

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[Table] There are no particular limitations on the dye contained in the recording layer of the optical recording medium of the present invention. For example, cyanine series, thiazolopyrimidine series, azaazulene series, azulene series, phthalocyanine series, pyrylium or thiapyrylium series, squalium series, quinone series, indoaniline series, naphthalocyanine series,
anthraquinone series, azo series, triphenylmethane series, azomethine series, styryl series, pyrazoline series,
It may be of any type such as aminobenzene. Among these, preferred are cyanine-based, thiazolopyrimidine-based, azaazulene-based, azulene-based,
Phthalocyanine-based, pyrylium- or thiapyrylium-based, squalium-based, quinone-based, and indoaniline-based dyes are preferred, with cyanine-based and quinone-based dyes being particularly preferred. Among the cyanine dyes, preferred are those represented by the following general formula described in JP-A-59-178295. φ−L=ψ(X ^- ) _n In the formula, φ and φ represent a 5- or 6-membered heterocyclic group, and this heterocycle can be a benzene ring, a naphthalene ring, a 5-, 6-, or 7-membered heterocycle. It may form a fused ring. As a heteroatom,
O, N, S, Se, Te are mentioned, preferably O,
N and S. L represents a linking group for forming a mono-, di-, tri-, or tetracarbocyanine dye. X represents an anion, provides the necessary negative charge to balance the charge of the molecule, and may be linked on φ or ψ to form an inner salt. m represents 0 or 1. Particularly preferred among the above cyanine dyes are:
φ and ψ are (Z is

[Formula] N-R, O, S or

[Formula], R, R', R'', and R ¹ represent a substituted or unsubstituted alkyl group or aryl group, and R ² , R ³ , R ⁴ , and R ⁵ represent a hydrogen atom or a substituent, for example, Represents an alkyl group, aryl group, heterocyclic group, halogen atom, alkoxy group, alkylthio group, alkyloxycarbonyl group, alkylcarbonyloxy group, carboxylic acid group, etc., or R ² and R ³ , R ³ and R ⁴ , R ⁴ and R ⁵ , R ⁵ and R ¹ , R
and R, R' and R'' may be connected to form a ring)
and L is (-CH=CR ⁶ -) _o (R ⁶ represents a hydrogen atom, an alkyl group, a phenyl group or a chlorine atom,
n represents an integer of 0 to 3). Examples of preferred thiazolopyrimidine cyanine dyes include compounds represented by the following general formula described in Japanese Patent Application No. 178504/1982. In the formula, A ₁ and A ₂ are each independently a hydrogen atom,
Represents a halogen atom, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group; Y is NR ₆ (R ₆
represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group. ), O, S, Se, or
Represents Te; Z' represents an atomic group necessary to form a 5-membered heterocycle; R ₁ , R ₂ , R ₃ and R ₄ are substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups; group, a substituted or unsubstituted aralkyl group, or a hydrogen atom; R ₅ is a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, or is bonded to Z' to form 6 represents an atomic group necessary to form a membered heterocycle; n represents 0, 1 or 2; X represents an anion; However, X is R ₁ ,
It may bind to R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , Z′, A ₁ or A ₂ to form an inner salt. Examples of preferable azaazulene dyes include compounds represented by the following general formula described in Japanese Patent Application No. 184500/1983. [In the formula, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ represent a hydrogen atom, a halogen atom, or a monovalent organic residue; A represents a divalent organic residue bonded by a double bond. represents an organic residue; X represents an anionic residue. However, X exists in the number necessary to neutralize the positive charge, and binds to R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , or A to form an intramolecular temperature. It's okay. Also R ₂ and R ₃ ,
At least one of the combinations of R ₃ and R ₄ , R ₄ and R ₅ , and R ₅ and R ₆ may form a substituted or unsubstituted aromatic carbocycle or aromatic heterocycle. ] Other preferred examples of dyes include those described in JP-A-57-
212639, 58−36490, 58−112790, 58−112792,
58−114989, 58−125246, 59−24692, 59−
55794, 59−55795, 59−67092, 59−71895, 59−
81194, 59−83695, 59−124045, 59−124897, 59
−188854, 59−85791, 59−150795, 59−202892,
60−19586, 60−19587, 60−47069, 60−78787,
60−83236, 60−83892, 60−162691, 60−
163243, 60−179292, 60−182029, 60−500329,
61−26044, 61−27551, 61−47295, 61−226035
etc. are described. In the present invention, a conjugate of a cation of a dye and an anion of the quencher can also be used. The optical recording medium of the present invention has a dye and the quencher supported on a substrate, and the quencher is generally used in an amount of 0.05 to 12 mol, preferably 0.1 to 1.2 mol, per 1 mol of the dye. The quencher is preferably contained in the dye thin film recording layer, but may be contained in the following layer separate from the recording layer. The optical recording medium of the present invention may further be provided with an undercoat layer on the substrate and a protective layer and a reflective layer on the recording layer, if necessary. Any known substrate can be used as the substrate. Typical examples include glass and plastic, and examples of plastic include acrylic, polycarbonate, polysulfone, polyimide, and polyester. Its shape can be various, such as a disk, card, sheet, or roll film. Guide grooves may be formed on the glass or plastic substrate to facilitate tracking during recording. Further, the glass or plastic substrate may be provided with a plastic binder or an undercoat layer such as an inorganic oxide or an inorganic sulfide. An undercoat layer having a lower thermal conductivity than the substrate is preferred. It is also possible to have a so-called air sandwich structure in which two recording media are placed facing each other with their recording layers inside. Formation of the recording layer in the present invention can be carried out, for example, by dissolving a dye and a quencher in an organic solvent (e.g., methanol, ethanol, isopropyl alcohol, dichloromethane, dichloroethane, acetone, etc.), and adding a suitable binder (e.g.,
PVA, PVP, polyvinyl butyral, polycarbonate, nitrocellulose, polyvinyl formal, methyl vinyl ether, chlorinated paraffin, maleic anhydride copolymer, styrene-butadiene copolymer, xylene resin) and apply the solution (for example, spin This can be done by co-depositing a dye and a quencher, or by vacuum-depositing a dye and then applying a quencher. When a binder is used, the weight of the binder is preferably 0.01 to 2 times the weight of the dye. The dye can also be used in the form of a thin film by the so-called Langmuir Blosget method. In the present invention, one or more recording layers are provided. An antioxidant or anti-fading agent may be present in the recording layer or in a layer adjacent thereto to prevent deterioration of the dye. The thickness of the recording layer is usually in the range of 0.01 μm to 2 μm, preferably 0.02 to 0.8 μm. In the case of reflective readout, it is particularly preferably an integer multiple of 1/4 of the laser wavelength used for readout. When providing a reflective layer for a semiconductor laser or a He-Ne laser, it is possible to provide a reflective layer on the substrate and then provide a recording layer on the reflective layer using the method described above, or to remove the recording layer from the substrate. One of the methods is to provide a layer and then provide a reflective layer thereon. The reflective layer can also be formed by other methods such as vapor deposition, evaporation, and ion plating. For example, a solution of a metal salt or metal complex salt dissolved in a water-soluble resin (PVP, PVA, etc.) and a reducing agent added thereto is applied to the substrate, and then heated and dried at 50°C to 150°C, preferably 60°C to 100°C. It is formed by The weight ratio of the metal salt or metal complex salt to the resin is 0.1 to 10, preferably 0.5 to 1.5. On this occasion,
The appropriate thickness of the recording layer is 0.01 to 0.1 μm for the metal particle reflective layer and 0.01 to 1 μm for the light absorption layer. As the metal salt or metal complex salt, silver nitrate, potassium silver cyanide, potassium gold cyanide, silver ammine complex, silver cyanide complex, gold salt, or gold cyanide complex can be used. Formalin as a reducing agent,
Tartaric acid, tartrates, reducing agents, hypophosphites, sodium borohydride, dimethylamine borane, etc. can be used. The reducing agent can be used in an amount of 0.2 to 10 mol, preferably 0.5 to 4 mol, per mol of metal salt or metal complex salt. In the optical recording medium of the present invention, information is recorded by irradiating the recording layer with a spot-like high-energy beam from a laser (e.g., semiconductor laser, He-Ne laser, etc.) through the substrate or from the side opposite to the substrate. , the light absorbed by the recording layer is exchanged for heat, forming pits (holes) in the recording layer. Further, information is read by irradiating a laser beam with a low output power below a recording threshold energy, and detecting a change in the amount of reflected light or the amount of transmitted light between the pit portion and the portion where no pit is formed. Hereinafter, the present invention will be explained in more detail with reference to Reference Examples and Examples. Reference Example 1 <Synthesis of Exemplary Compound (34)) (1-1) Bis(tetraethylammonium)
-bis(1,3-dithiol-2-thione-4,
Synthesis of 5-dithiolat) zinc complex. All reaction operations were performed under an argon atmosphere.
Cut 23g of sodium into small pieces and add 180ml of carbon disulfide.
After being dispersed in the solution, 200 ml of dimethylformamide was slowly added dropwise to the solution while stirring. Be careful not to generate too much heat at this time. After dropping dimethylformamide, the mixture was carefully heated and refluxed for 24 hours. After the reaction was completed, unreacted sodium was filtered off. Then add 50ml of ethanol to the filtrate.
was added and stirred at room temperature for 2 hours. Carbon disulfide is distilled off from this solution under reduced pressure at room temperature. Then 300ml of water
was slowly added dropwise, and the resulting solution was filtered. Next, add 20g of zinc chloride to methanol in advance.
Prepare a solution by dissolving 53g of tetraethylammonium bromide in 250ml of water and adding 500ml of concentrated ammonium water to it. Add this to the above reaction solution and stir for 5 minutes (at room temperature), then add an aqueous solution of 53g of tetraethylammonium bromide dissolved in 250ml of water. Immediately, a red precipitate begins to separate out. This was filtered and air-dried to obtain a zinc complex. (1-2)4,5-bis(benzoylthio)-
Synthesis of 1,3-dithiol-2-thione. Add 22 g of the zinc complex obtained in (1-1) to 500 g of acetone.
Dissolve in ml and filter. While stirring the filtrate, add 150 ml of benzoyl chloride. A yellow precipitate immediately separates out. Filter, wash with water and air dry to obtain the title compound.
Obtained 16g. (1-3) Synthesis of exemplified compound (34) Bis(benzoylthio) compound obtained in (1-2)
Dissolve 9.2g in 50ml of methanol. Add 6.3 g of a 28% methanol solution of sodium methoxide to this and stir for 10 minutes. A solution of 2.4 g of nickel chloride (hexahydrate) dissolved in 50 ml of methanol is added to this solution, and the mixture is stirred at room temperature for 30 minutes. When a solution of 8.5 g of tetrabutylphosphonium bromide dissolved in 100 ml of methanol is added to this solution, a black precipitate is immediately deposited. Stir for an additional 20 minutes, filter, wash with acetone, air dry, and recrystallize from acetone-isopropyl alcohol to give the title compound. Yield: 3.8g Reference Example 2 <Synthesis of Exemplified Compound (2)> 1g of the nickel complex obtained in (1-3) was dissolved in 60ml of acetone, 30ml of acetic acid was added thereto, the mixture was stirred for 3 hours, and the solvent was distilled off. Black crystals precipitated. This was recrystallized from acetone-methanol to obtain the target exemplary compound (2). Yield 0.4g,
mp185℃ λ _nax : 1125nm, ε _nax : 2.51×10 ⁴
(in CH ₂ Cl ₂ ) Reference Example 3 <Synthesis of Exemplary Compound (42)> (3-1) Bis(tetraethylammonium)
-bis(1,2-dithiol-3-thione-4,
Synthesis of 5-dithiorad) zinc complex. All reaction operations were performed under an argon atmosphere.
Cut 23g of sodium into small pieces and add 180ml of carbon disulfide.
After being dispersed in the solution, 200 ml of dimethylformamide was slowly added dropwise to the solution while stirring. Be careful not to generate too much heat at this time. After dropping dimethylformamide, the mixture was carefully heated and refluxed for 24 hours. After the reaction was completed, unreacted sodium was filtered off, and carbon disulfide was distilled off from the filtrate under reduced pressure at room temperature. The solution thus obtained was placed in an oil bath.
After stirring at 140°C for 2 hours, the mixture was allowed to cool to room temperature, 50 ml of ethanol was added thereto, stirred at room temperature for 2 hours, 300 ml of water was slowly added, and the resulting solution was filtered. Next, zinc chloride prepared in advance,
A solution of 20 g dissolved in 500 ml of methanol and 500 ml of concentrated ammonia water was added to the above reaction solution (at room temperature) and stirred for 5 minutes, then an aqueous solution of 53 g of tetraethylammonium bromide dissolved in 250 ml of water was added. A red precipitate will immediately separate out. This was filtered and air-dried to obtain the title zinc complex. (3-2)4,5-bis(benzoylthio)-
Synthesis of 1,2-dithiol-3-thione. Add 18 g of the zinc complex obtained in (3-1) to 500 g of acetone.
Dissolve in ml and filter. While stirring the filtrate, add 150 ml of benzoyl chloride. A yellow precipitate immediately separates out. After filtration, washing with water, and air drying, 12 g of the title compound was obtained. (3-3) Synthesis of exemplified compound (42) Bis(benzoylthio) compound obtained in (3-2)
Dissolve 9.2g in 50ml of methanol. To this was added 6.3 g of a 28% methanol solution of sodium methoxide, and the mixture was stirred for 10 minutes. Next, a solution of 2.4 g of nickel chloride (hexahydrate) dissolved in 50 ml of methanol was added to this solution, and after stirring at room temperature for 30 minutes, a solution of 7.5 g of tetrabutylammonium bromide dissolved in 100 ml of methanol was added to this solution. ,
A black precipitate was immediately deposited. The mixture was further stirred for 20 minutes, filtered, washed with acetone, and air-dried. Recrystallization from acetone-isopropyl alcohol gave the title compound. Yield: 2.8g Reference Example 4 <Synthesis of Exemplified Compound (10)> 1g of the nickel complex obtained in (3-3) was dissolved in 60ml of acetone, 30ml of acetic acid was added thereto, stirred for 3 hours, and the solvent was distilled off. Black crystals began to precipitate. When this was recrystallized from acetone-methanol, the title exemplary compound (10) was obtained. Yield 0.3 g, mp 207°C λ _nax : 1138 nm, ε _nax : 2.50×10 ⁴ (in CH ₂ Cl ₂ ) Example 1 The dye ( ), quencher ( ), and in some cases the binder shown in Table 1 were dissolved in methanol. It was dissolved in a mixed solvent of methyl ethyl ketone and dichloroethane in an appropriate ratio, applied to a surface-hardened acrylic plate to a thickness of 0.1 μm, and dried. When using a binder with a weight ratio of dye and quencher of 3:1, the weight of the binder is 1/5 of the weight of the dye.
And so. Using a semiconductor laser with a wavelength of 830 nm on the recording medium thus obtained, a 0.4 MHz signal was recorded under the conditions of 6 mW on the irradiation surface and a beam diameter of 1.6 μm.
A pit with a diameter of 1.0 μm was formed by irradiation for 0.3 μs. This recording section was irradiated with a weak laser beam, the signal was reproduced, and the C/N ratio was determined. Next, 1mW laser light (830nm) is applied to 1μsec width 3K.
After irradiating as a pulse of Hz for 10 minutes, the C/N ratio was determined, and the rate of decrease compared to the C/N ratio before laser beam irradiation was determined, which was used as a measure of reproduction deterioration. Also 60℃90%
The C/N ratio after being left at RH for 30 days was compared with the C/N ratio before storage as a measure of storage stability. Note that when the dyes were D, F, G, I, and J, experiments were conducted using a 780 nm semiconductor laser.

【table】

[Table] A pigment film was formed.
Example 2 Wavelength instead of semiconductor laser light with wavelength 780nm
Experiments were conducted using the combinations of dyes and quenchers shown in Table 2 in the same manner as in Example 1 using 830 nm semiconductor laser light. The results are shown in Table 2, and it can be seen that the combination of the quencher and dye of the present invention is more effective in increasing the stability of the recording medium than when a conventional quencher is used.

【table】

[Table] Compounds with the following structure.
* indicates a comparative example.
Dye K (Effects of the Invention) From the results in Tables 1 and 2, the optical recording medium of the present invention has less reproduction deterioration than the conventional optical recording medium;
That is, it can be seen that it has excellent read durability and storage stability.

Claims (1)

[Scope of Claims] 1. An optical recording medium characterized in that a dye and at least one compound represented by the following general formula [] or [] are supported on a substrate. (In the formula, [Cat ₁ ) and [Cat ₂ ] represent cations necessary to neutralize the complex, and M ₁ and M ₂ represent nickel, copper, cobalt, palladium, or platinum. n represents 1 or 2. )