JP3220840B2 - Dibenzoindocarbocyanine dye and optical information recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dibenzoindocarbocyanine dye having improved light fastness and an optical information recording medium using the same, and more particularly to a write-once optical information recording medium in a heat mode.

[0002]

2. Description of the Related Art A write-once optical information recording medium in a heat mode has been used as a means for recording and reproducing data such as images such as characters and figures or sound and the like.
In the write-once optical information recording medium in the heat mode, when recording is performed, a signal of an image taken by a camera, for example, a semiconductor laser or a helium.
The light is converted into an optical signal by a neon laser or the like and irradiated, and the reflectance of the recording layer is changed to form a pattern of the difference in reflectance corresponding to an image. On the other hand, when the reading is performed, the difference in the reflectance is detected by scanning with a weak laser beam, and the signal is converted into an image signal to display an image. As a recording layer having such an optical recording property, for example, a low-melting-point metal such as tellurium has been formed by vacuum vapor deposition on an insulating substrate. Optical information recording media using organic dyes such as vanadyl phthalocyanine and cyanine dyes having a relatively high reflectance in the recording layer have attracted attention among the dye materials. The recording layer using these organic dyes can be easily formed by a spin coating method, can be formed by a method with good productivity, has excellent oxidation resistance, does not corrode, and has a low thermal conductivity, so the influence of heat on the periphery And has the characteristic that it can be locally heated without affecting the recording quality, and is suitable for high-density recording. In particular, cyanine dyes have attracted attention because they exhibit high absorption and reflection in the wavelength region of semiconductor laser light of 700 to 900 nm.

However, a cyanine compound used in a recording layer for a write-once optical disc has poor light resistance, and a so-called “difference in reflectance” pattern formed in the recording layer is changed by changing a dye exposed to light. If pits are formed, the pit shape changes when stored or used under sunlight, and the recorded signal tends to change, so that high reliability may not be maintained. There's a problem. As a means for improving the light resistance, for example, as described in JP-A-59-55795, a singlet oxygen quencher is added to a cyanine-based compound, whereby oxygen activated by light irradiation is reduced. It is known that they are trapped to prevent oxidation of the cyanine-based compound and prevent deterioration due to light. Also, as described in JP-A-2-300288 and JP-A-3-232844, it is known that a nitrosodiphenylamine derivative is added as a light stabilizer to a cyanine compound to prevent deterioration due to light. Have been.

[0004]

However, the recording layer obtained by adding a light stabilizer such as a singlet oxygen quencher or a nitrosodiphenylamine derivative to a cyanine-based compound has a high reflectance even if the light resistance is improved. There is a problem that optical characteristics deteriorate. A first object of the present invention is to provide a dibenzoindocarbocyanine dye having improved light fastness. A second object of the present invention is to provide an optical information recording medium containing a cyanine dye having improved light fastness without deteriorating optical characteristics such as reflectance. A third object of the present invention is to store under sunlight,
It is an object of the present invention to provide an optical information recording medium containing a cyanine dye which does not decrease in reliability even when used. Fourth Embodiment of the Present Invention
An object of the present invention is to provide an optical information recording medium capable of achieving the above second and third objects even when a light stabilizer is used in combination.

[0005]

In order to solve the above-mentioned problems, the present invention provides (1) a compound represented by the following general formula (1):
Unhalogenated dibenzoin represented by the general formula excluding
Halon for carbocyanine dye after obtaining the dye
Represented by the following general formula [Chemical formula 1]
(However, when X is bonded to the central carbon of the pentamethine chain,
Dibenzoindocarbocyanine dyes ) .

[0006]

(Wherein R ₁ , R ₂ and R ₃ represent an alkyl group, A ⁻ represents a halogen atom, ClO ₄ ⁻ , BF ₄ ⁻ ,

[0007]

And X represents a halogen atom. )

The present invention also provides (2) an optical information recording medium having a recording layer containing the dibenzoindocarbocyanine dye of the above (1), (3), a dibenzoindocarbocyanine dye of the above (1). An optical information recording medium having a recording layer containing a dye and a nitrosodiphenylamine derivative represented by the following general formula [Chemical Formula 3];

[0009]

(Where R ₄ is a lower alkyl group, an amino group,
Halogen atom, nitro group, carboxyl group, cyano group,
1 selected from the group consisting of a hydroxyethyl group, an alkoxyl group, a sulfonamide group and its derivative, a carboxylic acid amide group and its derivative, and a trifluoroalkyl group
Represents one or more substituents, and n is a natural number of 1 to 3. ),

(4) An optical information recording medium according to the above (2) or (3), wherein X in the general formula [1] is Br.

Next, the present invention will be described in detail. In the present invention, the dibenzoindocarbocyanine-based dye represented by the general formula [Chemical Formula 1] includes R ₁ , R ₂ , R ₃ ,
A ^- and X are the same as those exemplified above. R ₁ is preferably a lower alkyl group such as a butyl group, and R ₂ and R ₃ are preferably a lower alkyl group such as a methyl group, and A is iodine or bromine. And the like, a halogen atom, perchloric acid and the like are preferable,
X is preferably Br. The light resistance is improved by the introduction of X, but can be improved by about 1.3 to 3 times, for example, as shown in Examples described later. X may be substituted at any position, but is preferably 0.3 to 1 part by weight of the dye before X was introduced.
It is preferred to react 0.5 parts by weight of, for example, bromine. If the amount is larger than this, bromination proceeds excessively and the solubility in an organic solvent becomes extremely low, so that it is difficult to easily form a coating film by spin coating. In addition, although the decomposition temperature is reduced due to the bromination, if the bromine is reacted too much, the decomposition temperature is too low, and the heat resistance is likely to deteriorate. Conversely, if the amount of bromine added is less than the above, the effect of improving light resistance becomes difficult to obtain. In consideration of these facts, by setting the bromination conditions (the amount of added bromine) so that the decomposition temperature is reduced to around 40 ° C. to 50 ° C., an optimal dye as an optical information recording medium can be obtained. The same applies to other halogens. The halogen may be used alone or in combination.

The compound represented by the general formula [Chemical formula 1] has a maximum absorption wavelength λ _nax slightly shorter _than that of the compound excluding X, its melting point is slightly lowered, and its decomposition temperature is lower than that of heat. Decomposes in the solvent and it does not develop color in a solvent (dimethylformamide), which is the temperature when the heat is applied). In order to produce the compound represented by the general formula [Chemical formula 1], a compound having the general formula excluding X from the [Chemical formula 1] is dissolved in a solvent (eg, chloroform), and a halogen solution such as a chloroform solution is added thereto. It is easily obtained by dropping and heating and stirring at 40 to 60 ° C. for 2 to 4 hours, and the product can be purified, for example, by column chromatography using chloroform. Specifically, in addition to those described in Examples described later, for example, halides of the following compounds can be exemplified.

[0013]

Embedded image

[0014]

Embedded image

[0015]

Embedded image

[0016]

Embedded image

[0017]

Embedded image

In the optical information recording medium of the present invention, the light resistance can be improved by a recording layer containing the compound of the above-mentioned formula [1]. Further, light resistance can be improved. As the mixing ratio, the compound of the general formula [Chemical Formula 1] / the compound of the general formula [Chemical Formula 3] = 8 to 9/2 to 1 is preferable. If the mixing ratio is less than this, the effect of improving the light resistance tends to decrease. If the amount is too large, the optical characteristics are likely to be adversely affected. The compounds represented by the above general formula [Chemical Formula 3] are described in JP-A-2-300288 and JP-A-3-232844, and their production methods are described in Tables 1 to 6 below. Compounds are preferred.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

[Table 3]

[0022]

[Table 4]

[0023]

[Table 5]

[0024]

[Table 6]

In order to produce the optical information recording medium of the present invention, a dye solution in which the compound of the above-mentioned formula [1] or the compound of the formula [3] is dissolved is prepared. Apply, but the solvent is chloroform,
Cellosolves such as dichloroethane, methyl ethyl ketone, dimethylformamide, methanol, diacetone alcohol, toluene, cyclohexanone, acetylacetone, and methyl cellosolve, and dioxane can be used, and the dye concentration is preferably 1 to 10%. In addition, as the material of the substrate, glass, epoxy resin, methacrylic resin, polycarbonate resin, polyester resin,
Polyvinyl chloride resin or the like can be used. In addition, in order to apply the above-mentioned dye solution to the substrate, it is preferable to use a spin coating method. In this case, the thickness of the coating layer after drying may be the one conventionally used.

[0026]

Next, an embodiment of the present invention will be described. For example, those belonging to the above general formula [1]
Each compound of [Chemical Formula 8] is dissolved in a solvent such as chloroform at a concentration of 10% by weight or less, and a solution obtained by dissolving a halogen such as bromine at a concentration of 5% by weight or less in chloroform is dropped at room temperature while stirring. I do. Then, it heat-stirs at 40-60 degreeC for 2-4 hours. After completion of the reaction, insolubles are removed by filtration, and the filtrate is concentrated and dried to obtain a crystalline powder. The crystals are sufficiently washed with water, dried again, and purified by chloroform column chromatography to obtain a brominated product of each dibenzoindocarbocyanine dye. Each of these dyes after bromination, or each of the compounds belonging to the above general formula [Chemical Formula 3], for example, each of the compounds shown in Tables 1 to 6, is mixed at a weight ratio of 8 to 9/2 to 1 to obtain diacetone. It is dissolved in alcohol at a concentration of 1 to 10%, applied to a polycarbonate substrate with a groove, and dried. Gold is sputtered on the coating film, and further overcoated with an ultraviolet curable resin, to produce a write-once optical information recording medium.

As described above, when a dibenzoindocarbocyanine compound is brominated, for example, when the compound is irradiated with light, the light energy is used for the vibration energy of the Br group, and the energy used for photodegradation is reduced. ,
It is considered that light degradation can be suppressed and the light resistance of the recording layer using the dye can be improved, but the details are not clear, and the present invention is not limited to this concept.

[0028]

Next, embodiments of the present invention will be described. Example 1 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide (NK, manufactured by Japan Photographic Dye Laboratories, Inc.)
3251) 1.5 parts by weight of chloroform was dissolved in 30 parts by weight of chloroform, and a solution of 0.6 part by weight of bromine dissolved in 15 parts by weight of chloroform was added dropwise at room temperature and stirred for 1 hour. Thereafter, the mixture was heated and stirred at 40 ° C. for 3 hours. After completion of the reaction, insolubles were removed by filtration, and the filtrate was concentrated and dried to obtain a crystalline powder. The crystals were sufficiently washed with water and dried again to obtain 1.7 parts by weight of washed crystal powder. The washed crystal powder was subjected to column chromatography purification with chloroform, and 1,1′-dibutyl 3,3,3 ′,
There was obtained 0.2 part by weight of a brominated product of 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide.

[0029]

Embedded image

This brominated dye has a maximum absorption wavelength λ _max
= 684 nm (measured in diacetone alcohol),
The melting point was 190 to 198 ° C and the decomposition temperature was 210 to 220 ° C. In addition, the measured value of the above-mentioned dye before the bromination was measured by the same measuring method as described above: λ _max = 688 nm, melting point 196 to 2
02 ° C, decomposition temperature 265-275 ° C. From these results, it can be seen that the decomposition temperature of the brominated product was 55 ° C. lower than that before the bromination. To determine the lightfastness, the resulting 1,1′-dibutyl 3,
3,3 ′, 3′-Tetramethyl-4,5,4 ′, 5 ′ Dibenzoindodicarbocyanine iodide bromide was added to 1,2-dichloroethane at 20 g / l (liter).
And a spin coater (2,000 rpm)
m) and applied to a glass plate, and using a solar simulator (SSS-501S-ER manufactured by Ushio Inc.), light irradiation (light amount 0.13 Mlux) was performed at room temperature. The light resistance is based on the absorbance at the maximum absorption wavelength before light irradiation (10
As 0), the rate of decrease in absorbance (discoloration rate) with respect to light irradiation (integrated light quantity) was measured. FIG. 1 shows a solid line (after Br conversion).
And the dotted line (before Br) shows the result. Comparing the integrated light amount when the color has faded to 50%, the value before Br conversion is 0.29 Mluxhr, and the value after Br conversion is 0.88 Ml.
uxhr, indicating that the light resistance was improved about three times.

The obtained 1,1′-dibutyl 3,3,
Brominated 3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide and nitrosodiphenylamine derivative (4
-Nitroso-4'-dimethylaminodiphenylamine)
(JP-A-2-300288) was mixed at a weight ratio of 9: 1, dissolved in diacetone alcohol at a concentration of 30 g / l, and applied to a grooved polycarbonate substrate. Gold was sputtered on the coating film, and the film was further overcoated with an ultraviolet curable resin. Recording was performed on the write-once optical information recording medium thus manufactured using a semiconductor laser having a wavelength of 783 nm at a linear velocity of 1.2 m / sec. The reflectance was 67%, and the optimum recording power was 8 mW. The light resistance of the obtained write-once optical information recording medium was examined in the same manner as described above, and the result is shown in FIG. 2 by a solid line (after Br conversion).

Comparative Example 1 In Example 1, instead of using the dye after bromination, the above-mentioned dye 1, 1'-dibutyl 3,
3,3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide (NK32
Light resistance was examined in the same manner except for using the above (51), and a write-once optical information recording medium was produced. The measurement results of light fastness are shown by the dotted line (before Br conversion) in FIG. A linear velocity of 1.2 m was applied to this write-once optical information recording medium using a semiconductor laser having a wavelength of 783 nm.
As a result, the reflectance was 66% and the optimum recording power was 8 mW. From the results of FIG. 2, it can be seen that, even with the addition of the light stabilizer, the one after bromination has better light resistance and the difference in reflectance is smaller than that before bromination.

Example 2 In Example 1, 1,1′-dibutyl 3,3,3 ′,
Instead of 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide (NK3251), 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4, 5,1′-Dibutyl 3,3 shown in the following [Chemical Formula 10] in the same manner except that 5,4 ′, 5 ′ dibenzoindodicarbocyanine perchloride (NK3219 manufactured by Japan Photosensitive Dye Laboratories Inc.) was used. 3 ',
A brominated product of 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine perchloride was obtained.

[0034]

Embedded image

The value of this brominated dye measured by the same measuring method as in Example 1 was λ _max = 682 nm (measured in diacetone alcohol), melting point: 180 to 185 ° C., decomposition temperature: 220 to 230 ° C. Was. Incidentally, the measured value of the above dye before the bromination by the same measuring method is λ _max = 6.
88 nm, melting point 182-185 ° C, decomposition temperature 270-2
80 ° C. From these results, it can be seen that the decomposition temperature of the brominated product is lower by 50 ° C. than that before the bromination. In Example 1, the 1,1 ′ obtained above was used instead of using the dye after bromination there.
-Dibutyl 3,3,3 ', 3'-tetramethyl-4,
The light resistance was examined in the same manner except that brominated 5,4 ′, 5 ′ dibenzoindodicarbocyanine perchloride was used.
0.99 Mluxhr. In Example 1, instead of using the dye after bromination there, 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ obtained above. A write-once optical information recording medium was prepared in the same manner except that brominated dibenzoindodicarbocyanine perchloride was used. The write-once optical information recording medium thus manufactured was recorded at a linear velocity of 1.2 m / sec using a semiconductor laser having a wavelength of 783 nm.
The reflectance was 65%, and the optimum recording power was 8.5 mW.

Comparative Example 2 In Example 2, instead of using the dye after bromination, the above dye 1,1'-dibutyl 3, before bromination,
3,3 ′, 3′-Tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine perchloride (NK3
219), except that the light resistance was examined in the same manner to produce a write-once optical information recording medium. Light fastness measurement result is 5
The integrated light amount when fading to 0% is 0.74 Mluxh
r. This write-once optical information recording medium has a wavelength of 783n.
As a result of recording at a linear velocity of 1.2 m / sec using a semiconductor laser of m, the reflectivity was 66% and the optimum recording power was 9 mW.
Met. From the above results, it can be seen that, even with the addition of the light stabilizer, the one after bromination has better light resistance and less difference in reflectance than the one before bromination.

Example 3 In Example 1, 1,1′-dibutyl 3,3,3 ′,
Instead of 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine iodide (NK3251), 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4, 5, 4 ', 5' dibenzoindodicarbocyanine bromide (manufactured by Japan Photographic Dye Laboratories, Inc.)
NK3567) except that
A brominated product of 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine bromide shown in 1) was obtained.

[0038]

Embedded image

The value of this brominated dye measured by the same measuring method as in Example 1 was λ _max = 680 nm (measured in diacetone alcohol), melting point: 182 to 188 ° C., decomposition temperature: 220 to 230 ° C. Was. Incidentally, the measured value of the above dye before the bromination by the same measuring method is λ _max = 6.
88 nm, melting point 210-215 ° C, decomposition temperature 260-2
70 ° C. From these results, it can be seen that the decomposition temperature of the brominated product is lower by 40 ° C. than that before the bromination. In Example 1, the 1,1 ′ obtained above was used instead of using the dye after bromination there.
-Dibutyl 3,3,3 ', 3'-tetramethyl-4,
The light resistance was examined in the same manner except that a brominated product of 5,4 ′, 5 ′ dibenzoindodicarbocyanine bromide was used. The integrated light amount when the color faded to 50% was 0.9.
7Mluxhr. In Example 1, instead of using the dye after bromination there, 1,1′-dibutyl 3,3,3 ′, 3′-tetramethyl-4,5,4 ′, 5 ′ obtained above. A write-once optical information recording medium was prepared in the same manner except that brominated dibenzoindodicarbocyanine bromide was used. The write-once optical information recording medium thus manufactured was recorded at a linear velocity of 1.2 m / sec using a semiconductor laser having a wavelength of 783 nm. Reflectivity is 6
8%, and the optimum recording power was 8.6 mW.

Comparative Example 3 In Example 3, instead of using the dye after bromination, the above dye 1,1'-dibutyl 3, before bromination,
3,3 ′, 3′-Tetramethyl-4,5,4 ′, 5 ′ dibenzoindodicarbocyanine bromide (NK356
Light resistance was examined in the same manner except that 7) was used, and a write-once optical information recording medium was produced. Light fastness measured 50%
The integrated light amount when the color faded to 0.70 Mluxhr. As a result of recording on this write-once optical information recording medium at a linear velocity of 1.2 m / sec using a semiconductor laser having a wavelength of 783 nm, the reflectance was 68% and the optimum recording power was 8.8 mW.
Met. From the above results, it can be seen that, even with the addition of the light stabilizer, the one after bromination has better light resistance and less difference in reflectance than the one before bromination.

Although the above description has been made with respect to an optical recording medium using a light stabilizer in combination, an optical recording medium produced in the same manner except that no light stabilizer was used also gave results similar thereto.

50% of Examples 1-3 and Comparative Examples 1-3
The measured value of the integrated light amount when the color faded to the maximum, the melting point, the decomposition temperature, and the maximum absorption wavelength λ _{nax of} the dye used in each of Examples and Comparative Examples.
Are summarized in Table 7. The dyes used in Comparative Examples 1 to 3 are represented by chemical formulas obtained by removing Br from the chemical formulas of the brominated dyes used in the corresponding examples.

From the above, the above-mentioned (1) “dibenzoindocarbocyanine-based dye represented by the following general formula [Chemical Formula 1]” was replaced with “dibenzoindocarbonate represented by the following general formula [Chemical Formula 1]”. The amount of accumulated light at a fading rate of 50% is 1.3 times or more (or 1%) with respect to a dibenzoindocarbocyanine dye represented by the general formula excluding X in the general formula [Chemical Formula 1]. (3 to 3 times) a dibenzoindocarbocyanine-based dye which can be increased, and "a dibenzoindocarbocyanine-based dye represented by the following general formula [Chemical formula 1]" to "A general formula [Chemical formula 1] Wherein the decomposition temperature is 4 times lower than the decomposition temperature of the dibenzoindocarbocyanine compound represented by the general formula except for X of the general formula [Chemical Formula 1].
A dibenzoindocarbocyanine dye capable of reducing the temperature by 0 to 55 ° C. And "a dibenzoindocarbocyanine dye represented by the following general formula [Chemical Formula 1], wherein the dibenzoindocarbocyanine dye represented by the general formula excluding X in the general formula [Chemical Formula 1]. On the other hand, the dibenzoindone represented by a general formula excluding X in the general formula [Chemical Formula 1] can increase the integrated light amount by 1.3 times or more (or 1.3 to 3 times) at a fading rate of 50%. A dibenzoindocarbocyanine-based dye capable of lowering the decomposition temperature of the carbocyanine-based compound by 40 to 55 ° C. ", wherein X of the general formula [Formula 1] is changed to Br, and at least one other limitation is added. You can also. Further, the invention of an optical information recording medium using the “dibenzoindocarbocyanine-based dye” with these limitations as the dye of the above (2) or later can also be constituted.

[0044]

According to the present invention, the above-mentioned general formula [1]
Halogenated dibenes represented by the general formula excluding X
After obtaining a zoindcarbocyanine dye,
That Harongen the general formula obtained by the reduction is represented by [Formula 1] (wherein, X is bonded to the central carbon of the pentamethine chain
Because it provides to except to have compounds) dibenzo Indian carbocyanine based compound, to improve the light resistance, it is possible to provide a dibenzo Indian carbocyanine type dye which can reduce the decomposition temperature, thereby the reflectivity or the like Has a recording layer containing a dibenzoindocarbocyanine dye capable of improving the light resistance without deteriorating the optical characteristics of the optical recording medium. An optical information recording medium can be provided. Further, by using a light stabilizer in combination, it is possible to provide an optical information recording medium which achieves the above-mentioned effects and can achieve even better effects.

[Brief description of the drawings]

FIG. 1 is a graph showing the light resistance of one example of the dibenzoindocarbocyanine dye of the present invention and a comparative example of the compound before bromination.

FIG. 2 is a graph showing the light resistance of optical information recording media according to one embodiment of the present invention and a comparative example.

[Table 7]

Continuation of the front page (56) References JP-A-5-58049 (JP, A) JP-A-5-85057 (JP, A) JP-A-6-72047 (JP, A) JP-A-5-579 (JP) JP-A-64-40387 (JP, A) JP-A-64-49682 (JP, A) JP-A-64-40389 (JP, A) JP-A-64-40390 (JP, A) JP-A-64-40381 (JP, A) JP-A-64-40388 (JP, A) JP-A-60-234892 (JP, A) JP-A-60-118749 (JP, A) JP-A-62-258991 (JP, A A) JP-A-2-59393 (JP, A) JP-A-60-44390 (JP, A) JP-A-2-300288 (JP, A) JP-A-3-232844 (JP, A) Opt. Spektrosk. , 51 (6), 1002-8 (1981) Izv. Akad. Nauk SSS R, Ser. Fiz, 42 (3), 557-61 (1978) Zh. Org. Khim. , 8 (3), 635-40 (1972) East Tead. Akad. Toim, Fuus. , Mat. , 40 (3), 177-80 (1991) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09B 23/00 C07D 209/60 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] [Claim 1] In the following general formula [Chemical formula 1], X is excluded.
Unhalogenated dibenzoindocarboxy represented by the general formula
After obtaining an anine-based dye,
Represented by the following general formula [Formula 1] (provided that
A compound in which X is bonded to the central carbon of the ntametin chain
Excluding) dibenzoindocarbocyanine dyes. Embedded image (However, R ₁ , R ₂ and R ₃ represent an alkyl group;
^- a halogen ^{_{atom, ClO 4 -, BF 4 -}} , ## STR2 ## X represents a halogen atom. ) 2. An optical information recording medium having a recording layer containing the dibenzoindocarbocyanine dye according to claim 1. 3. An optical information recording medium having a recording layer containing the dibenzoindocarbocyanine dye according to claim 1 and a nitrosodiphenylamine derivative represented by the following general formula [3]. Embedded image (However, R ₄ is a lower alkyl group, an amino group, a halogen atom, a nitro group, a carboxyl group, a cyano group, a hydroxyethyl group, an alkoxyl group, a sulfonamide group and its derivatives, a carboxamide group and its derivatives, One or more substituents selected from the group consisting of alkyl groups are shown, and n is a natural number of 1 to 3.) 4. The optical information recording medium according to claim 2, wherein X in the general formula [Formula 1] is Br.