JP2000302992A - Polymethine-based dye compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new inexpensive compound having a high absorptivity coefficient in the near-infrared region, excellent in solubility to an organic solvent or the like, and useful as a polymethine-based dye. SOLUTION: This new compound is a compound of formula I (R1 to R4 are each H or a monovalent organic residue, and a ring is formed with a combination of R1 and R2 or a combination of R3 and R4, each end of R1 to R4 binds to C positioning at an ortho position with respect to N bound to the aromatic ring; R5 to R8 are each H, a halogen or a monovalent organic residue; R9 to R12 are each H, OH, or a monovalent organic residue; n is 0 to 3), e.g. 1,5-bis(p-dimethylaminophenyl)-1,5-bis(p-tolyl)-2,4-pentadienol bis[3,5-bis(tert- butylsalicyl)] borate of formula II. The compound of formula I is obtained, for example, through the following processes: discharging a solution obtained by dissolving a perchlorate of formula III and a salicylic borate of formula IV in dimethylformamide, into water; filtering crystals thus deposited; washing them with water; and drying the crystals thus washed.

Description

DETAILED DESCRIPTION OF THE INVENTION

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BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymethine dye compound (referred to as polymethine dye) used for near-infrared absorption filters, light-to-heat conversion materials, and the like.

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2. Description of the Related Art In a light-to-heat conversion material, a near-infrared absorbing dye is often used as a medium for recording of light-to-heat conversion using a heat mode. This means that the dye medium absorbs the laser light at the oscillation wavelength, converts the light into heat as emission energy, and uses that heat energy to perform recording, morphological change, or phase transformation. Things. Specifically, with the spread of computers,
In recent years, the printing industry has proposed plate material configurations and various lithographic plate making methods. Conventionally, a method of producing a positive or negative film and printing it on a lithographic printing original plate has been adopted. However, an electrophotographic plate, a silver halide photographic plate, an electronic typesetting, and a DTP (desktop publishing), which make a plate directly from under the plate without passing through the film. ) A lithographic plate that can be printed and printed directly on a plate using a laser or thermal head without visualizing the printed image information edited and produced in step (CTP) (Compute)
r to Plate), and tends to increase in the future.

The development (washing-out and removal of the uncured portion) required for the existing PS plate is performed in view of the working environment and processing at the work site, preparation of the developer, preparation and time loss required for the preparation, and development process management. There is a demand to make this unnecessary. The thermal CTP has a configuration in which a heat-sensitive layer is provided on a substrate. This heat-sensitive layer has a structure in which fine particles containing a lipophilic component are dispersed in a hydrophilic material. By direct heating with a thermal head or the like, the printed portion is converted to lipophilic and becomes a phase having affinity for the ink. It is to convert. In order to further improve the resolution, a method has been devised in which a laser beam is used, a near-infrared absorbing dye is dispersed in the above-mentioned heat-sensitive layer, and the printing portion is similarly subjected to phase conversion to produce a printing original plate. For example, JP-A-7-1849. In this case, the near-infrared absorbing dye in the thermosensitive layer is
It functions as a medium that can absorb laser light and convert it into heat.

On the other hand, in the electronic equipment industry, a plasma display (PDP) replacing a CRT has recently been developed as a large display and a thin display, and has already been put into practical use. By the way, PDP involves the emission of electromagnetic waves by plasma emission due to the system structure. This electromagnetic wave is near-infrared light, and has a wavelength similar to that of near-infrared light emitted from a remote control device frequently used mainly in home electric appliances recently. Therefore, when a PDP is used near a home appliance using such a remote control device, the home appliance may malfunction due to near-infrared light generated from the PDP. As a solution to this, it is common to provide a shield for blocking near-infrared light on the screen. For this shield, a resin processed by kneading a near-infrared absorbing dye or the like into a film shape or a resin coated on a film-shaped resin has been devised.

The near-infrared absorbing dye used in such a medium preferably has a high absorption in the near-infrared region. Specifically, the absorption in the near-infrared region is 600 to 1000 nm, preferably 750 to 850 nm. It has absorption. Extinction coefficient, the better high but is preferably 10 ⁵ or more (molar extinction coefficient). Further, it is desirable to sufficiently dissolve in various organic solvents and the like from the viewpoint of processing. Further, in view of the marketability, an inexpensive one is desired. Conventionally, those reported as near-infrared absorbing dyes include, for example, polymethine dyes, phthalocyanine dyes, dithiol metal complex dyes, naphthoquinones, anthraquinones, triphenylmethane dyes, aminium, diimmonium dyes, and azo dyes There are a wide variety of dyes such as disperse dyes, indoaniline metal complex dyes, and intermolecular CT dyes (for example, JP-A-5-112078, JP-A-6-241).
No. 45, JP-A-8-197843, JP-A-10-14
0022, JP-A-10-186127, JP-A-10-186127
-180947).

However, these are still required due to insufficient durability, low absorption coefficient, insufficient dissolution in organic solvents and the like, high cost, and cannot be used commercially. The performance has not been satisfied.
In particular, solubility in organic solvents and the like is high in terms of processing, and known polymethine dyes such as Cl ⁻ , Br ⁻ , I ⁻ , and C ⁻
Polymethine dyes using IO ₄ ⁻ , IO ₄ ⁻ , SbF ₆ ^{− and the} like as counter anions have poor solubility and are difficult to handle in processing.

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The present invention focuses on the poor solubility of this polymethine dye in an organic solvent and seeks to improve it.

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That is, the present invention relates to a polymethine dye represented by the general formula (1).

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In the formula (1), R1 to R4 are a hydrogen atom or a monovalent organic residue, and a combination of R1 and R2 or R3 and R4 may form a ring. Further, the terminals of R1 to R4 may be bonded to carbon positioned ortho to the nitrogen atom bonded to the aromatic ring to form a ring. R5 to R8 are a hydrogen atom, a halogen or a monovalent organic residue, R9 to R1
2 means a hydrogen atom, a hydroxyl group or a monovalent organic residue. n means the integer of 0-3.

In R1 to R4 of the general formula (1), the monovalent organic residue is more specifically a methyl group, an ethyl group, a propyl group, an iso-propyl group, a butyl group, an isocyanate group.
an alkyl group having 1 to 6 carbon atoms such as an o-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group; 5-6 such as a cyclopentyl group and a cyclohexyl group;
Membered cycloalkyl groups; and arylalkyl groups having 10 or less carbon atoms, such as benzyl, phenylethyl, phenylpropyl, and phenylbutyl groups. In the case of ring formation, R1 to R4 each represent an alkylene group selected from, for example, ethylene, propylene, and trimethylene. In this case, the other end not bonded to a nitrogen atom is
A ring is formed by bonding to the benzene nucleus carbon at the ortho position of the nitrogen atom, or bonding at the other end of R1 and R2 or at the other end of R3 and R4.

In R5 to R8 and R9 to R12, examples of the monovalent organic residue include the alkyl groups having 1 to 6 carbon atoms described above; methoxy, ethoxy, propoxy, An alkoxy group having 1 to 6 carbon atoms such as a butoxy group, a pentoxy group and a hexyloxy group; an acetyl group; an amino group represented by the formula -N (R13) R14 (wherein R1
3, R14 is an alkyl group having 1 to 6 carbon atoms as exemplified above; a 5- or 6-membered cycloalkyl group;
An arylalkyl group of 0 or less; or an alkylene group selected from ethylene, propylene, and trimethylene. In the case of alkylene, the other end not bonded to a nitrogen atom is
Bond to the benzene nucleus carbon at the ortho position of the nitrogen atom, or bond at the other end of R13 and R14 to form a ring).

The preferred polymethine dyes of the present invention include -N (R1) R2 and -N (R3) of the general formula (1).
R4 is the same group selected from a dimethylamino group, a diethylamino group and a pyrrolidino group, and R5 and R6 are selected from a methyl group, an ethyl group, a dimethylamino group, a diethylamino group, a methoxy group, an ethoxy group and a chlorine atom The same group, wherein R7 and R8 are both hydrogen atoms, and R9 and R10 or R11 and R12 are the same group selected from a methyl group, an ethyl group, a propyl group, a butyl group, a hydroxyl group and a methoxy group; (R9 and R
10 or one of R11 and R12 is a hydrogen atom), and n is 0 or 1
Is the compound when The polymethine dye of the present invention has a high absorption coefficient in the near-infrared region, is excellent in solubility in organic solvents and the like, is inexpensive, and can satisfy the above-mentioned performance. Specific examples of these polymethine dyes will be shown.

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DESCRIPTION OF THE PREFERRED EMBODIMENTS In synthesizing the polymethine dye salicylborate of the present invention, a precursor perchlorate (A) and salicylic acid borate (B) are charged in dimethylformamide as shown in the following formula. After stirring and dissolving, the solution may be discharged into water, and the precipitated crystals may be collected by filtration, washed with water and dried.

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In producing the polymethine dye represented by the general formula (1), first, the precursor perchlorate (A)
Is, for example, S. Wildy (BS Wild)
i) et al., Journal of American Chemical Society (Journalof American)
Chemical Society) ”80, 377
2-3777, 1958. That is, it can be obtained by adding diarylethylene and ethyl orthoformate in acetic anhydride, further adding 60% perchloric acid, and performing a heating reaction. Alternatively, diarylethylene and diarylketone can be obtained by adding diarylethylene and diarylketone to phosphorus oxychloride and performing a heating reaction. The diaryl ketone as a raw material intermediate can be obtained, for example, by reacting a dialkylaniline with a benzanilide derivative in phosphorus oxychloride under heating. Diarylethylene can be obtained, for example, by reacting diarylketone with methylmagnesium bromide in THF. Salicylic acid borate (B), which is an anion, can be obtained, for example, by reacting a salicylic acid derivative and boric acid in toluene with sodium carbonate and benzamide, followed by heating.

Specific examples of salicylic acid derivatives include salicylic acid, 3-methylsalicylic acid, 4-methylsalicylic acid,
5-methylsalicylic acid, 3-phenylsalicylic acid, 5-
Chlorosalicylic acid, 3,5-dichlorosalicylic acid, 4,
6-dihydroxysalicylic acid, 4,6-dimethoxysalicylic acid, 3,5-di-tert-butylsalicylic acid,
3,5-di-α-methylbenzylsalicylic acid, 3,5-
Di (α, α-dimethylbenzyl) salicylic acid, 3-diphenylmethylsalicylic acid, 2-oxide-1-naphthoic acid, 2-oxide-3-naphthoic acid, 1-oxide-2
-Naphthoic acid and the like.

As described above, a polymethine dye obtained as an ion pair salt comprising a combination of a known polymethine dye cation and salicylborate anion has an absorption in the near infrared region. This absorption is specifically between 700 and 9
It has a high extinction coefficient and is soluble in various organic solvents. The solubility in organic solvents depends on the substituents of the dye. In the dye of the present invention, the substituent in the cation moiety also has an effect of affecting the solubility, but directly affects the absorption wavelength, and is not suitable for improving only the solubility without significantly changing the wavelength. If a substituent is introduced into salicyl borate ion as an anion part, only the solubility can be changed without changing the wavelength. That is, the solubility was able to be improved even in an organic solvent which is hardly dissolved by perchlorate ions or halogen ions which are inorganic anions. Specifically, acetone, chloroform,
It shows high solubility even in organic solvents such as dimethylformamide (DMF) and dimethylsulfoxide (DMSO), and is very useful in processing for various uses. Next, the present invention will be described specifically with reference to examples.

[0037]

EXAMPLES Example 1 1,5-bis (p-dimethylaminophenyl) -1,5
Synthesis of -bis (p-tolyl) -2,4-pentadienol, bis (3,5-bis (tert-butylsalicyl)) borate "dye of formula (2)". 1,5-bis (p-dimethylaminophenyl) -1,5
-Bis (p-tolyl) -2,4-pentadienol, 11.7 g of perchlorate and 12.7 g of sodium bis (3,5-bis (tert-butylsalicyl)) borate were added to 200 ml of DMF, and stirred at room temperature under stirring. Left for hours. The reaction solution was dropped into 1600 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A dark blue crystalline solid was obtained in a yield of 90.7%. (Elemental analysis): C65H77N2O6B Calculated: C: 78.63 H: 7.76 N: 2.82 Analytical value: C: 78.52 H: 7.98 N: 3.08

Example 2 1,5-bis (p-dimethylaminophenyl) -1,5
Synthesis of -bis (p-methoxyphenyl) -2,4-pentadienol, bis (3,5-bis (tert-butylsalicyl)) borate "dye of formula (3)". 1,5-bis (p-dimethylaminophenyl) -1,5
-Bis (p-methoxyphenyl) -2,4-pentadienol, 49.3 g of perchlorate and 50.9 g of sodium bis (3,5-bis (tert-butylsalicyl)) borate are added to 800 ml of DMF, and the mixture is stirred at room temperature. Left for 2 hours. The reaction solution was added dropwise to 6400 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours.
A dark blue crystalline solid was obtained with a yield of 97.7%. (Elemental analysis): C65H77N2O8B Calculated value: C: 76.18 H: 7.52 N: 2.71 Analysis value: C: 76.63 H: 8.48 N: 3.36

Example 3 Synthesis of 1,1,5,5-tetrakis (p-diethylaminophenyl) -2,4-pentadienol, bis (3-methylsalicyl) borate “dye of the formula (6)” 1,1,5,5-Tetrakis (p-diethylaminophenyl) -2,4-pentadienol, 7.5 g of perchlorate and 4 g of sodium bis (3-methylsalicyl) borate are added to 50 ml of DMF and stirred at room temperature for 2 hours. I left it. The reaction solution was dropped into 800 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A dark blue crystalline solid was obtained with a yield of 84.0%. (Elemental analysis) As C59H71N4O6B Calculated: C: 70.00 H: 7.02 N: 5.53 Analytical value: C: 69.87 H: 7.76 N: 5.96

Example 4 1,5-bis (p-dimethylaminophenyl) -1,5
-Synthesis of bis (p-methoxyphenyl) -2,4-pentadienol, bis (4,6-dihydroxysalicyl) borate "dye of formula (9)". 1,5-bis (p-dimethylaminophenyl) -1,5
-Bis (p-methoxyphenyl) -2,4-pentadienol, perchlorate (12.3 g) and sodium bis (4,6-dihydroxysalicyl) borate (8.9 g) were added to DMF (200 ml), and the mixture was allowed to stand at room temperature with stirring for 2 hours. The reaction solution was dropped into 1600 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A black crystalline solid was obtained with a yield of 98.8%. (Elemental analysis) As C49H45N2O12B Calculated: C: 68.06 H: 5.21 N: 3.24 Analytical value: C: 68.33 H: 6.03 N: 3.72

Example 5 Synthesis of 1,1,5,5-tetrakis (p-pyrrolidinophenyl) -2,4-pentadienol, bis (5-methoxysalicyl) borate “dye of formula (10)” 6. 1,1,5,5-tetrakis (p-pyrrolidinophenyl) -2,4-pentadienol, perchlorate
5 g and sodium bis (5-methoxysalicyl) borate (4.4 g) were added to DMF (100 ml), and the mixture was left at room temperature with stirring for 2 hours. The reaction solution was dropped into 800 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A dark blue crystalline solid was obtained with a yield of 80.8%. (Elemental analysis) As C61H63N4O8B Calculated: C: 73.94 H: 6.36 N: 5.66 Analytical value: C: 74.11 H: 6.89 N: 5.60

Example 6 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-methoxyphenyl) -2-propenol,
Synthesis of bis (5-methoxysalicyl) borate "dye of formula (13)". 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-methoxyphenyl) -2-propenol,
5.9 g of perchlorate and 4.4 g of sodium bis (5-methoxysalicyl) borate were added to 100 ml of DMF, and the mixture was left at room temperature with stirring for 2 hours. The reaction solution is
ml. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A black crystalline solid was obtained with a yield of 83.9%. (Elemental analysis): C49H47N2O10B Calculated: C: 70.50 H: 5.64 N: 3.36 Analysis: C: 70.23 H: 5.81 N: 3.73

Example 7 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-tolyl) -2-propenol, bis (5-
Synthesis of “Methoxysalicyl) borate“ Dye of formula (14) ”. 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-tolyl) -2-propenol, 5.6 g of perchlorate, sodium bis (5-methoxysalicyl)
4.4 g of borate was added to 100 ml of DMF, and the mixture was left at room temperature with stirring for 2 hours. The reaction solution was dropped into 800 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours.
A black crystalline solid was obtained with a yield of 99.5%. (Elemental analysis): C49H47N2O8B Calculated: C: 69.83 H: 5.58 N: 3.33 Analysis: C: 69.72 H: 5.82 N: 3.02

Example 8 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-chlorophenyl) -2-propenol, bis (4,6-dihydroxysalicyl) borate [Formula (1)
6) Synthesis of dye ”. 1,3-bis (p-dimethylaminophenyl) -1,3
-Bis (p-chlorophenyl) -2-propenol, 4.2 g of perchlorate, 2.6 g of sodium bis (4,6-dihydroxysalicyl) borate in 100 ml of DMF
And left at room temperature for 2 hours with stirring. Water 8
It was dropped into 00 ml. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. Wash and 2 at 60 ° C
Dried for 4 hours. A gray crystalline solid was obtained with a yield of 66.5%. (Elemental analysis) As C45H37N2O10BC12 Calculated: C: 63.75 H: 4.37 N: 3.31 Analytical values: C: 64.07 H: 4.72 N: 3.55

Example 9 Synthesis of 1,1,5,5-tetrakis (p-dimethylaminophenyl) -2,4-pentadienol, bis (5-methoxysalicyl) borate “dye of the formula (17)” 1,1,5,5-tetrakis (p-dimethylaminophenyl) -2,4-pentadienol, perchlorate 1
2.9 g and sodium bis (5-methoxysalicyl) borate (7.3 g) were added to DMF (200 ml), and the mixture was left at room temperature with stirring for 2 hours. The reaction solution was dropped into 1600 ml of water. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours.
A black-brown crystalline solid was obtained at a yield of 87.3%. (Elemental analysis) As C53H55N4O8B Calculated: C: 71.78 H: 6.21 N: 6.32 Analytical value: C: 71.84 H: 6.03 N: 6.59

Example 10 1,5-bis (p-dimethylaminophenyl) -1,5
-Synthesis of bis (p-tolyl) -2,4-pentadienol, bis (5-methoxysalicyl) borate "dye of formula (18)". 1,5-bis (p-dimethylaminophenyl) -1,5
-Bis (p-tolyl) -2,4-pentadienol, 5.8 g of perchlorate and 4.4 g of sodium bis (5-methoxysalicyl) borate were added to 100 ml of DMF,
The mixture was left at room temperature with stirring for 2 hours. 800 ml of water
Was dropped. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A brown crystalline solid was obtained with a yield of 84.5%. (Elemental analysis): C51H49N2O8B Calculated: C: 73.91 H: 5.92 N: 3.38 Analytical value: C: 74.25 H: 6.01 N: 3.88

Example 11 1,5-bis (p-pyrrolidinophenyl) -1,5-bis (p-methoxyphenyl) -2,4-pentadienol, bis (5-methoxysalicyl) borate [formula ( 1
9) Synthesis of dye ”. 1,5-bis (p-pyrrolidinophenyl) -1,5-bis (p-methoxyphenyl) -2,4-pentadienol, perchlorate 13.4 g, sodium bis (5-methoxysalicyl) borate 7.3 g 200 ml of DMF
And left at room temperature for 2 hours with stirring. Water 1
It was added dropwise to 600 ml. After completion of the dropwise addition, stirring was continued for 2 hours, and the precipitated crystalline solid was separated by filtration. It was washed and dried at 60 ° C. for 24 hours. A dark purple crystalline solid was obtained in a yield of 88.0%. (Elemental analysis) As C55H53N2O10B Calculated: C: 70.82 H: 6.18 N: 3.15 Analysis: C: 70.76 H: 6.68 N: 3.64

Test Example 1 At room temperature, 1 part by weight of the dye of the formula (2) was weighed and placed in a screw-neck bottle, and the amount of acetone was gradually increased so that the dye was washed with an ultrasonic cleaner Branson 2200 (trade name). Acetone was added for 5 minutes with shaking by Yamato) until dissolution.
As a result, the solubility of the dye was 1.3% by weight. Test Examples 2 to 23 The solubility test was performed in the same manner as in Test Example 1, except that the dyes shown in Table 1 and the organic solvents were used instead of the dyes of the formula (2).

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[Table 1]

Test Examples 24 to 29 A solubility test was carried out in the same manner as in Test Example 1, except that the dye of the formula (2) was replaced with a known dye of the following formula and an organic solvent. The results are shown in Table 1 above.

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Industrial Applicability The polymethine dye of the present invention has an absorption in the near-infrared region and has good solubility in various organic solvents, so that it can be used for various applications, and has high industrial utility value. is there.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01J 11/02 G02B 1/10 Z F-term (Reference) 2H048 CA04 CA12 CA19 2K009 CC21 EE01 4H048 AA01 AB92 AB99 VA20 VA22 VA77 VB10 4H056 CA02 CA03 CC06 CE02 CE03 DD03 FA03 FA05 5C040 GH10 KA14 KB14 MA08

Claims (2)

[Claims] A polymethine dye compound represented by the general formula (1): In the formula (1), R1 to R4 are a hydrogen atom or a monovalent organic residue, and may form a ring by a combination of R1 and R2 or a combination of R3 and R4. Further, the terminals of R1 to R4 may be bonded to carbon positioned ortho to the nitrogen atom bonded to the aromatic ring to form a ring. R5 to R8 are hydrogen atoms,
A halogen or a monovalent organic residue, R9 to R12 means a hydrogen atom, a hydroxyl group or a monovalent organic residue. n
Represents an integer of 0 to 3. 2. In the formula (1), -N (R1) R2 and -N (R
3) R4 is the same group selected from a dimethylamino group, a diethylamino group and a pyridino group, and R5 and R6 are a methyl group, an ethyl group, a dimethylamino group, a diethylamino group, a methoxy group, an ethoxy group and a chlorine atom R7 and R8 are both hydrogen atoms, and R9 and R10 or R11 and R12 are the same groups selected from a methyl group, an ethyl group, a propyl group, a butyl group, a hydroxyl group and a methoxy group. (R9 and R
10 or one of R11 and R12 is a hydrogen atom), and n is 0 or 1
The polymethine dye compound according to claim 1, wherein