JPH11349920A - Near infrared absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new compound having a structure obtained by converting the hydrogen atom bonded to nitrogen atom of an aminothiophenolate metal complex dye into an aryl group and useful as a near infrared absorber having strong absorption in near infrared range and high chemical stability and easily formable to a film. SOLUTION: The objective compound is expressed by formula I (R<1> and R<2> are each an aryl; the rings A and B are each benzene ring; X is S or Se; M<1> is Ni, Pd or the like; Z<+> is a cation), e.g. tetrabutylammonium bis(2- phenylaminobenzenethiol) nickel complex. The compound of formula I can be produced e.g. by dissolving compounds of formula II and formula III in a solvent, ionizing the compounds by the addition of metallic potassium or potassium hydroxide, reacting with a cation of Ni, etc., and stabilizing by the addition of a quaternary salt of nitrogen, phosphorus or arsenic. The compound of formula I can be used e.g. as a dye for near infrared-absorbing optical recording material, a dye for infrared absorbing filter, a dye for laser printer, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorbent exhibiting absorption in the near infrared region, and more specifically, a dye for an optical recording material, a dye for an infrared absorption filter, a dye for a data code, and a dye for a light shielding film. And a near-infrared absorber used as a dye for blocking heat rays, a dye for a laser printer, a singlet oxygen quencher, an anti-fading agent and the like.

[0002]

2. Description of the Related Art For each application of a dye having absorption in the near-infrared light region, the properties that the material should have are different from each other. It needs to be stable. Further, depending on the field of application, since it is used in the form of a film, it must be easy to form a film under given conditions. Several such materials have been developed. For example, squarylium,
Cyanine dyes, metal phthalocyanines, platinum bis (dithio-α-diketone) complex compounds, and the like. Squarylium has a problem that the absorption rate is low and the state of the formed film is poor.
Platinum bis (dithio-α-diketone) complex compounds have the problem of poor film formability and chemical instability. Thus, conventionally developed near-infrared light absorbing dyes have some problems and have not been put to practical use. Also, JP-A-63-11
No. 2592 discloses a near-infrared absorbing dye represented by the following general formula (II) as an aminothiophenolate-based metal complex dye.

[0003]

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(Wherein R represents a hydrogen atom, an alkyl group, an alkoxy group, a nitro group, a halogen, an amino group, or a substituted amino group, D represents a sulfur, selenium, or imino group, and E represents a hydrogen atom or an amino group. R ′ represents an alkyl group, and m represents 1 or 2.)

[0005]

However, the near-infrared absorbing dye represented by the general formula (II) has a problem in that it has poor light fastness. An object of the present invention is to provide a dye material that has a large absorption in the near infrared light region, is chemically stable, and is easy to form a film.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors, in the dye represented by the above general formula (II), replace hydrogen bonded to nitrogen with a substituent. By changing to an aryl group which may be used, the present inventors have found that they have strong absorption in the near infrared region, have high solubility in organic solvents, are easy to form a film, and are excellent in light resistance, and have reached the present invention. That is, the gist of the present invention is represented by the following general formula (I)

[0007]

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(Wherein, R ¹ and R ² each represent an optionally substituted aryl group;

[0009]

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Is a benzene ring which may have a substituent, X is S or Se, M ¹ is Ni, Pd,
Co, Fe, TiO, Sn, SnCl ₂ or Cu, Z
⁺ Represents a cation. )).

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In the present specification, Me represents a methyl group, Et represents an ethyl group, Bu represents a butyl group, Pr represents a propyl group, Ph represents a phenyl group, i- is iso, n- is linear, and t- is Represents tertiary. R ¹ and R ² each represent an aryl group which may have a substituent such as an aryl group, an alkyl group and a halogen atom, and preferably an aryl group,
An aryl group which may be substituted with an alkyl group, more preferably an unsubstituted aryl group is used.
The alkyl group substituted with the aryl group usually has 1 to 5 carbon atoms.
And the halogen atom substituted for the aryl group is usually
Cl, F, Br and the like. R ¹ and R ² may be different from each other, but are preferably the same from the viewpoint of synthesis and the like.

[0012]

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[0013] The benzene ring represents a benzene ring which may have a substituent. When the benzene ring has a substituent, the benzene ring may have the same or different substituents. But,

[0014]

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Are preferably the same. Preferably,

[0016]

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Wherein each of R ^{3 to} R ¹⁰ represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a nitro group, a halogen atom, an amino group, a substituted amino group or a cyano group. A hydrogen atom, a methyl group, an ethyl group, an i-butyl group, a t-butyl group, an alkyl group having 1 to 5 carbon atoms such as an n-butyl group, an aryl group,
Halogen such as aralkyl group such as benzyl group and phenethyl group, alkoxy group having 1 to 5 carbon atoms such as methoxy group, ethoxy group, t-butoxy group and n-butoxy group, nitro group, chlorine atom, bromine atom and fluorine atom. Examples include an atom, an amino group, a dimethylamino group, a diethylamino group, a substituted amino group such as a diphenylamino group, and a cyano group, and more preferably, a hydrogen atom and the like. Specifically,

[0018]

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And the like.

[0020]

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And the like. X represents S or Se, and S is preferably used. M ¹ is Ni, Pd,
Pt, Co, Fe, TiO, Sn, SnCl ₂ or C
u, preferably Ni. Z ⁺ represents a cation, preferably [R ¹¹ R ¹² R ¹³ R
¹⁴ M ² ] ⁺ , an optionally substituted N-alkyl-substituted pyridinium cation or an optionally substituted N-phenyl-substituted pyridinium cation.

R ^{11 to} R ¹⁴ each represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent or an aralkyl group which may have a substituent. And preferably represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms which may have a substituent such as an alkoxy group, an aryl group or an aralkyl group, more preferably a hydrogen atom or an alkyl group. Groups and aryl groups are used. R ¹¹ and R ¹² may be linked to each other to form an M ² atom-containing aliphatic ring.

M ² represents nitrogen, phosphorus or arsenic, and preferably nitrogen or phosphorus is used. [R ¹¹ R ¹² R ¹³
R ¹⁴ M ² ] ⁺ include Me ₄ N ⁺ , Et ₄ N ⁺ , n-
Pr ₄ N ⁺ , i-Pr ₄ N ⁺ , n-Bu ₄ N ⁺ , Ph ₄
N ⁺ , Me ₄ P ⁺ , Et ₄ P ⁺ , n-Pr ₄ P ⁺ , i-
Pr ₄ P ⁺ , n-Bu ₄ N ⁺ , Ph ₄ P ⁺ ,

[0024]

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And the like. Examples of the optionally substituted N-alkyl-substituted pyridinium cation include:

[0026]

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And the like. Examples of the N-phenyl-substituted pyridinium cation which may have a substituent include:

[0028]

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And the like. The near infrared absorbing dye of the present invention is preferably represented by the following general formulas (II) to (IV).

[0030]

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In the formula, R ¹⁵ represents an alkyl group which may have a substituent, preferably an alkyl group such as a methyl group, an ethyl group, an n-butyl group, an i-butyl group, an n-butyl group, and the like. Preferably, an alkyl group having 1 to 5 carbon atoms is used.

[0032]

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Represents a benzene ring which may have a substituent, preferably a benzene ring, a 2,6-dialkylbenzene ring, a 2,4,6-trialkylbenzene ring, and more preferably a benzene ring. . Of these,
Those of the general formula (II) are preferably used. The near-infrared absorbing dye of the present invention can be produced, for example, as follows. That is, the following general formula (V)

[0034]

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(Where:

[0036]

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R ¹ , R ² and X have the same meanings as in formula (I). ) Is dissolved in a solvent,
After ionization by adding potassium metal or potassium hydroxide, Ni, Pd, Pt, Co, Fe, TiO, S
By reacting with a cation such as n, SnCl ₂ or Cu complex, and further stabilizing by adding a quaternary salt of nitrogen, phosphorus or arsenic, a deep blue to green-white dye represented by the general formula (I) The compound represented can be synthesized.

The above reaction is usually performed in a solvent. As the solvent, for example, tetrahydrofuran (hereinafter “TH
F "), ethers such as diethylene glycol dimethyl ether, triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether, alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, cyclohexanol and octanol, and 1,2,3-trichloropropane Halogenated aliphatic hydrocarbons such as tetrachloroethylene, 1,1,2,2-tetrachloroethane and 1,2-dichloroethane, aliphatic hydrocarbons such as cyclohexane, hexane and octane, benzene, toluene, xylene,
Mesitylene, monochlorobenzene, dichlorobenzene,
Aromatic hydrocarbons such as nitrobenzene and squalane;
Amides such as N-dimethylformamide, N, N, N ', N'-tetramethylurea; sulfoxides such as dimethyl sulfoxide and sulfolane; nitriles such as acetonitrile, propanenitrile and benzonitrile; ethyl acetate; methyl propionate And esters such as methyl enanthate, methyl linoleate and methyl stearate. Among these solvents, alcohol solvents and ether solvents are preferred.

The reaction temperature is between room temperature and 0 ° C.
It can be carried out smoothly at 50 ° C. The compound represented by the general formula (V) can be synthesized by N-arylation of 2-aminobenzenethiol. In addition, L of phenothiazine
It can also be synthesized by a reductive ring opening reaction with a reducing agent such as i. For example, N-phenyl substituted N-
Phenyl-o-aminobenzenethiol is described in WO961
According to 6051, it can be synthesized as follows. That is, as shown in the formula (VI), Li can be reacted with phenothiazine to synthesize N-phenyl-o-aminobenzenethiol.

[0040]

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The compounds of the present invention may be various functional dyes, for example, dyes for near-infrared absorbing light recording materials, dyes for infrared absorbing filters, dyes for data codes, dyes for light-shielding films, dyes for blocking heat rays, laser printers It can be used as a dye for use, a singlet oxygen quencher, an anti-fading agent and the like.

[0042]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by this. Synthesis Example 1 of Ligand A lithiated form of N-phenyl-o-aminobenzenethiol was synthesized as follows with reference to WO9616051. 0.40 g of phenothiazine (0.002
mol) in 20 ml of THF.
g (0.012 mol) was reacted at room temperature with stirring for 2 hours, and unreacted metal Li was separated by decantation. The lithiated form of N-phenyl-o-aminobenzenethiol synthesized in this manner was used in the reaction described in the following examples as it was in a THF solution.

Example 1 0.24 g of nickel (II) chloride hexahydrate was added to a THF solution of a lithiated form of N-phenyl-o-aminobenzenethiol synthesized in Synthesis Example 1 of the above ligand. 001
mol) was dissolved in 10 m of ethanol and added.
The solution turned green. Thereafter, 0.64 g (0.002 mol) of tetrabutylammonium bromide was added, and the mixture was reacted with stirring for 1 hour. After filtration, washing and drying, tetrabutylammonium bis (2-phenylaminobenzenethiol) represented by the formula (VII) was added. ) The nickel complex was isolated (yield 0.59 g; 84% yield). This complex showed a strong absorption in methanol at 908 nm, which is a near-infrared region, with ε = 35000.

[0044]

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Further, in order to evaluate the light fastness, a polymethyl methacrylate resin (0.6 g) was added to 0.6 g of a 5% by weight solution of bis (2-phenylaminobenzenethiol) nickel complex obtained in Example 1 in methyl ethyl ketone as follows. Trade name: BR-80: a product of Mitsubishi Rayon Co., Ltd.) in methyl ethyl ketone / toluene (= 1/1) (resin concentration 2
0% by weight) and completely dissolved in an ultrasonic washer.
Coating was performed on an HP film to obtain a near infrared absorbing film. The coating film pressure was 6 μm.

The near-infrared absorption of this film was measured with a Hitachi spectrophotometer U-3500.
55 nm. In addition, a Xenon Long Life Fade Meter (FAL-25AX-HCB)
-EC) (manufactured by Suga Test Instruments Co., Ltd.) and the absorption intensity before and after irradiation at 1055 nm was measured for 200 hours. The intensity after irradiation was 70.9% of the intensity before irradiation.
It was confirmed that the light resistance was high.

Comparative Example 0.004 mol of KOH was dissolved in about 20 ml of ethanol, and 0.50 g of o-aminobenzenethiol was added to the solution.
10 ml of a (0.004 mol) ethanol solution was added with stirring to obtain a ligand solution. On the other hand, nickel (II) chloride hexahydrate 0.48
g (0.002 mol) was dissolved and added dropwise to the ligand solution with stirring, and the solution turned dark blue.

After stirring for about 1 hour in this state, tetrabutylammonium bromide was added to 10 ml of ethanol.
A solution in which 002 mol was dissolved was added, and the mixture was further stirred for 1 hour. The formed precipitate was separated by filtration, washed with ethanol, and dried to obtain tetrabutylammonium bis (aminobenzenethiol) nickelate represented by the formula (VIII) in a yield of 0.61 g (yield: 56%). This complex showed an absorption of ε = 24000 at 807 nm in a methanol solution.

[0049]

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When the obtained dye was formed into a film by the same method as in Example 1, λmax was 824 nm. Xenon Long Life Fade Meter (FA
L-25AX-HCB-EC) (manufactured by Suga Test Instruments Co., Ltd.), and the absorption intensity before and after irradiation at 824 nm was measured for 200 hours. The intensity after irradiation was 50.8% of the intensity before irradiation. there were.

Example 2 Example 1 was repeated except that tetrabutylphosphonium bromide was used instead of tetrabutylammonium bromide.
Was performed in the same manner as described above. After filtration, washing and drying, a complex having a tetrabutylphosphonium cation represented by the formula (IX) was isolated (yield 0.57 g; yield 80).
%). This complex has ε = 920 nm in methanol at 920 nm.
A strong absorption of 36000 was shown.

[0052]

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Example 3 0.004 mol of KOH was dissolved in about 20 ml of ethanol, and 0.49 g (0.004 mol) of N-methyl-o-aminobenzenethiol in ethanol was added to the solution.
0 ml was added with stirring to obtain a ligand solution. On the other hand, nickel (II) chloride.
When 0.48 g (0.002 mol) of the hydrate was dissolved and added dropwise to the ligand solution with stirring, the solution turned dark blue green.

After stirring for about 1 hour in this state, 0.8 ml of N-methylpyridinium iodide was added to 10 ml of ethanol.
A solution in which 8 g (0.004 mol) was dissolved was added, and the mixture was further stirred for 1 hour. The resulting precipitate is filtered off, washed with ethanol and dried, yielding 0.54 g (63% yield).
Thus, an N-methylpyridinium bis (2-methylaminobenzenethiol) nickel complex represented by the formula (X) was obtained. This complex is 876 nm in methanol solution.
Showed strong absorption at ε = 29220.

[0055]

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Example 4 0.004 mol of KOH was dissolved in about 20 ml of ethanol, and 0.49 g (0.004 mol) of N-methyl-o-aminobenzenethiol in ethanol was added to the solution.
0 ml was added with stirring to obtain a ligand solution. On the other hand, nickel (II) chloride.
When 0.48 g (0.002 mol) of the hydrate was dissolved and added dropwise to the ligand solution with stirring, the solution turned dark blue green.

After stirring for about 1 hour in this state, a solution of 1.00 g (0.004 mol) of N-isopropylpyridinium iodide in 10 ml of ethanol was added, and the mixture was further stirred for 1 hour. The resulting precipitate was filtered off, washed with ethanol and dried, yielding 0.49 g (yield 5
3%) to obtain an N-isopropylpyridinium bis (2-methylaminobenzenethiol) nickel complex represented by the formula (XI). This complex is a methanol solution,
A strong absorption of ε = 33640 was shown at 888 nm.

[0058]

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Example 5 0.24 g of nickel (II) chloride hexahydrate was added to a THF solution of a lithiated form of N-phenyl-o-aminobenzenethiol synthesized in Synthesis Example 1 of the above ligand. 001
mol) was dissolved in 10 ml of ethanol and added. The solution turned green. Thereafter, a solution of 0.44 g (0.002 mol) of N-methylpyridinium iodide in 20 ml of ethanol was applied thereto, followed by filtration, washing and drying, followed by N-methylpyridinium bis (2-phenylaminobenzenethiol) represented by the formula (XII). ) 0.44 g (0.002 mol) of nickelate tol complex was obtained in a yield of 0.39 g (71% yield). This complex showed a strong absorption of ε = 29280 at 1055 nm in a methanol solution.

[0060]

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[0061]

According to the present invention, a dye exhibiting strong absorption in the near infrared region and having excellent light resistance can be provided. In addition, since the dye of the present invention has high solubility in an organic solvent, it is easy to form a film, and a coating film can be obtained in a simple coating state.

Claims (3)

[Claims] 1. A compound represented by the following general formula (I) (Wherein, R ¹ and R ² each represent an aryl group which may have a substituent; Is a benzene ring which may have a substituent, X
Is S or Se, M ¹ is Ni, Pd, Co, Fe,
TiO, Sn, SnCl ₂ or Cu, Z ⁺ represents a cation. A near-infrared absorber represented by). (2) (R ^{3 to} R ¹⁰ each represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, an aralkyl group which may have a substituent, The near-infrared absorbing agent according to claim 1, which represents an alkoxy group, a nitro group, a halogen atom, an amino group, a substituted amino group, or a cyano group which may have the following formula: 3. Z ⁺ is [R ¹¹ R ¹² R ¹³ R ¹⁴ M ² ]
⁺ (R ^{11 to} R ¹⁴ each represent a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, or an aralkyl group which may have a substituent,
R ¹¹ and R ¹² may be linked to each other to form a nitrogen-containing aliphatic ring, M ² represents nitrogen, phosphorus or arsenic), an optionally substituted N-alkyl-substituted pyridinium cation or The near-infrared absorber according to claim 1, which is an N-phenyl-substituted pyridinium cation optionally having a substituent.