JPH08245579A - Diarylethene photochromic compound and optically recording material using the compound - Google Patents

Abstract

PURPOSE: To obtain the component useful as an optically recording material. CONSTITUTION: A compound of formula I (the ring B is a cyclic hydrocarbon group, a heterocyclic group; R is H, an alkyl, an aryl, a cycloalkyl; the carbon atoms on the rings C and D may have substituents, respectively, or may form condensed rings together with the carbon atoms on the same rings). The compound of formula I is obtained e.g. by dropping a n-BuLi hexane solution on a compound of formula II and subsequently adding perfluorocyclopentene to the reaction product. An optically recording material having a recording layer containing the compound of formula I is obtained by dispersing or dissolving the compound of formula I in a solvent (e.g. carbon tetrachloride), if necessary, together with a binder such as a polyester resin and subsequently coating the obtained dispersion or solution on a substrate, or forming the recording layer on the substrate by a vacuum-deposition method or a vacuum-codeposition method. The optically recording material is excellent in semiconductor laser sensitivity, non-destructive read, record thermal stability, high response speed, repeating durability, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a diarylethene photochromic compound and an optical recording material using the compound.

[0002]

2. Description of the Related Art A photochromic material is a material containing a molecule or a molecular assembly which reversibly produces two isomers having different states by the action of light. The photochromic material reversibly changes its light absorption coefficient, refractive index or dielectric constant with its photoisomerization. These changes in optical properties have been applied to optical functional media such as optical memory media or optical switch elements. For these purposes, development of photochromic molecules such as diarylethene compounds and fulgide compounds, which have repeated durability and are irreversible with heat, has been advanced. At present, diarylethene molecules having sufficient cyclic durability and thermal irreversibility have been obtained (M. Irie, Mol. Cyrst. Liq. C).
ryst. 227, 263 (1993)). Conventional diarylethene molecules exhibit the following photochromic reaction.

[0003]

[Chemical 11]

At this time, the ring-opened body shown on the left has an absorption maximum in the short wavelength region, and the ring-closed body shown on the right has an absorption maximum in the long wavelength region. Usually, the ring-closing reaction requires rotation of the molecule, and therefore it is easy to introduce a threshold value into this reaction process (M. Irie et al. J. Am. Che.
m. Soc. 116, 9894 (1994)). As a result, a photochromic reaction system that photoreacts only at high temperature was constructed. When this is used for nondestructive readout, simultaneous irradiation with two wavelengths is required (F. Tate
zono at al. Jpn. J. Appl. Phy
s. 32, 3987 (1993)). If the ring-opened body has an absorption maximum in the longer wavelength region than the ring-closed body, the nondestructive readout method is simplified, and the single-wavelength light source enables the nondestructive readout.

[0005]

SUMMARY OF THE INVENTION The inventor of the present invention needs to adjust the π
It was found that the conjugation length can be shortened by a ring-closing reaction, and for that purpose, it was studied to bond it to the ethene moiety at the 2-position of the thiochen ring.

[0006]

[Chemical 12]

In the ring-opened state, the two aryl groups are conjugated through the ethene moiety. If a long conjugated chain is introduced at the 5-position, the π-conjugated chain length will be further increased. Due to the long conjugation, the absorption maximum position is expected to have a longer wavelength.
On the other hand, when the ring-closing reaction occurs, the π-conjugation thereof is localized in the cyclohexadiene ring, and therefore the absorption maximum position is considered to be shorter than that in the ring-opened form.

[0008]

Means for Solving the Problems The present inventor has synthesized a photochromic compound having a following structure of a diarylethene system having a 5-membered hetero ring in the aryl portion.

[0009]

[Chemical 13]

In each of the above formulas, ring A, ring A'and ring B represent a hydrocarbon ring or a heterocycle,

[0011]

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Represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group, and represents -R ¹ , -R ² , -R ⁴ , -R ⁵ , -R ⁶ , -R
¹² and -R ¹³ each independently represent an alkyl group, a halogen atom or a trifluoromethyl group, and -R ⁸ and -R ¹³
R ⁹ represents an optionally substituted hydrocarbon aromatic ring or heteroaromatic ring, wherein carbon atoms on ring C and ring D have a substituent or are taken together with an adjacent carbon atom on the same ring. Form a ring that is fused to the ring.

That is, the first gist of the present invention resides in a diarylethene photochromic compound represented by the above general formula (I). A second gist of the present invention resides in a diarylethene-based photochromic compound represented by the above general formula (II). Further, a third aspect of the present invention is an optical recording material having a recording layer for recording optical information by changing its optical properties by light irradiation, the recording layer being represented by the above general formula (I). An optical recording material is characterized by containing a diarylethene-based photochromic compound. Fourth of the present invention
The gist of the present invention resides in the optical recording material, wherein the diarylethene-based photochromic compound is represented by the general formula (III) or (IV). Hereinafter, the present invention will be described in detail. In the above general formulas [I], [II], [III] and [IV],
Specific examples of the hydrocarbon ring or heterocycle represented by ring B include the followings.

[0014]

[Chemical 15]

Further, -R, -R ¹ , -R ² , -R ⁴ ,-
Examples of the alkyl group represented by R ⁵ , -R ⁶ , -R ¹² and -R ¹³ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, sec- A butyl group, an n-pentyl group, an n-heptyl group, an n-hexyl group, an n-octyl group, a 2-ethylhexyl group, an n-stearyl group and the like, C _1-20 , preferably a C _1-4 straight chain or Examples thereof include branched alkyl groups. -R ¹ , -R ² ,
-R ^4, examples of the halogen atom represented by -R ¹² and -R ^13, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom. The substituent of the alkyl group, aryl group or cyclohexyl group represented by R is, for example, an alkoxy group, an alkoxyalkoxy group, an alkoxyalkoxyalkoxy group, an allyloxy group, an aryl group, an aryloxy group, a cyano group or a hydroxy group. , Tetrahydrofuryl group and the like. Specific examples of the diarylethene-based photochromic compound according to the present invention include the following.

[0016]

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[0017]

[Chemical 17]

[0018]

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[0019]

[Chemical 19]

[0020]

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[0021]

[Chemical 21]

[0022]

[Chemical formula 22]

[0023]

[Chemical formula 23]

[0024]

[Chemical formula 24]

[0025]

[Chemical 25]

[0026]

[Chemical formula 26]

[0027]

[Chemical 27]

[0028]

[Chemical 28]

[0029]

[Chemical 29]

[0030]

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[0031]

[Chemical 31]

[0032]

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[0033]

[Chemical 33]

[0034]

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[0035]

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The optical recording material of the present invention having a recording layer containing the diarylethene-based photochromic compound of the present invention can be easily obtained according to a known method.
The optical recording material of the present invention which requires a recording layer containing the diaryl-based photochromic compound of the present invention can be easily obtained according to a known method. For example, (a) a compound of the present invention, if necessary, a polyester resin, a polystyrene resin, a polyvinyl butyral resin,
With binders such as polyvinylidene chloride, polyvinyl chloride, polymethylmethacrylate, polyvinyl acetate, cellulose acetate, epoxy resin, phenol resin, carbon tetrachloride, benzene, cyclohexane, methyl ethyl ketone,
Dispersed or dissolved in a solvent such as tetrachloroethane and coated on a suitable substrate, or by vapor deposition on a suitable substrate by a known vapor deposition method or co-evaporation method with another compound, etc. A recording layer is formed on.

(B) The compound of the present invention is dissolved in the above-mentioned solvent and then enclosed in a glass tray or the like. The optical recording material of the present invention can be manufactured by forming the recording layer by the method described above.

In the method (a), the substrate used may be either transparent or opaque to the light used. Examples of the material of the substrate material include supports for general recording materials such as glass, plastic, paper, plate-shaped or foil-shaped metal, and among these, plastic is preferable from various points. As the plastic, acrylic resin, methacrylic resin, vinyl acetate resin, vinyl chloride resin, nitrocellulose, polyethylene resin, polypropylene resin, polycarbonate resin, polyimide resin,
Examples thereof include polysulfone resin.

The film thickness of the recording layer formed on such a substrate is 100 Å to 100 μm, particularly 1000 Å to 10 μm.
Is preferred. Further, as a film forming method, a commonly used thin film forming method such as a vacuum vapor deposition method, a sputtering method, a doctor blade method, a casting method, a spinner method and a dipping method can be adopted.

When a binder is used for film formation,
It is desirable that the amount of the ethylene derivative according to the present invention is 5% or more by weight. In the case of film formation by the spinner method, the rotation speed is preferably 500 to 5000 rpm, and after spin coating, treatment such as heating or applying to solvent vapor may be performed depending on the case.

When the recording layer is formed by a coating method such as a doctor blade method, a casting method, a spinner method, a dipping method, or a spinner method, the coating solvent is bromoform,
Dibromoethane, ethyl cerolube, xylene, chlorobenzene, cyclohexanone and the like having a boiling point of 120 to 160 ° C. are preferably used.

In the present invention, a transition metal chelate compound (eg, acetylacetonate chelate, bisphenyldithiol, salicylaldehyde oxime, bisdithio-) is used as a singlet oxygen quencher in the recording layer in order to improve its stability and light resistance. (α-diketone, etc.) or a tertiary amine compound may be contained. The recording layer of the optical recording material of the present invention may be provided on both sides of the substrate, or may be provided on only one side.

Recording on the optical recording material of the present invention obtained as described above is performed by irradiating a recording layer provided on both sides or one side of a substrate or a recording layer in a cell with light focused to about 1 to 10 μm. To do. Then, the light-irradiated portion undergoes a color change due to absorption of light energy. The recorded information can be reproduced by reading the difference in reflectance or absorbance between the portion where color change due to light has occurred and the portion where color change due to light has not occurred.

As the light source used for the optical recording material of the present invention, a mercury lamp, a xenon lamp, a laser beam (N ₂ , He-Cd, Ar, He-Ne,
Ruby, semiconductor, dye laser) and the like. Of these, it is most preferable to use laser light.

[0045]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist. Example 1 Production Example of Compound

[0046]

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3.70 g of 3-methylthiophene (48 m
mol) and TMEDA (tetramethylene ethylenediamine) 8.4 ml (56 mmol) with dry ether 40 m
It was dissolved in 1 and stirred at room temperature. 35 ml (56 mmol) of n-BuLi hexane solution (1.6 N) was added dropwise thereto, and the mixture was stirred at room temperature for 2 hours. To this, an ether solution of zinc chloride 1N, 56 ml (56 mmol) and dry THF 50
ml was added, and the mixture was stirred at room temperature for 4 hours.

In a separate reaction vessel, p-iodoanisole 1
1.232 g (48 mol) and tetrakis (triphenylphosphine) Pd (0) catalyst (560 mg) were mixed with anhydrous THF.
And then add the above reaction solution to this,
After heating at 0 ° C. for 2 hours, the mixture was stirred overnight at room temperature. After completion of the reaction, the mixture was extracted with water-ether, the ether layer was dried over MgSO ₄ , and evaporated. The residue was developed by silica gel chromatography using hexane as a solvent to obtain the target compound 3
2.21 g was obtained. (Yield 26%)

[0049]

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Melting point: 54-56 ° C. MS: M ⁺ (204) ¹ H-NMR (CDCl ₃ ), δ 2.26 (3H,
s, Me), 3.83 (3H, s, MeO), 6.77.
(1H, s, 3-H), 6.90 (2H, d, J = 8H
₂ ), 7.01 (1H, s, 5-H), 7.50 (2
H, d, J = 8H ₂ )

[0051]

[Chemical 38]

Compound 3 0.7 g (3.43 × 10 ^-3 m
ol) is dissolved in a mixed solvent consisting of 4 ml of acetic acid and 4 ml of carbon tetrachloride. To this, 0.4 ml of water and 150 m of iodic acid
A solution of g (0.85 mmol) and iodine 300 m
g (1.18 × 10 ⁻³ mol) was added, and the mixture was heated under reflux for 5 hours until the spot of the raw material disappeared by TLC. After the reaction,
It was poured into water, neutralized with an aqueous solution of sodium carbonate, treated with hypo water, and extracted with chloroform. The extracted chloroform solution was dried over MgSO ₄ , the solvent was distilled off, and the resulting solid was purified by silica gel chromatography with a mixture of hexane 4: benzene 1 to obtain 0.71 g of compound 4 .
(Yield 63%) was obtained.

[0053]

[Chemical Formula 39]

Melting point: 89-94 ° C. MS: M⁺331¹ H-NMR (CDCl₃) Δ2.21 (3H, s, M
e), 3.83 (3H, s, MeO), 6.85 (1
H, s, 3-H), 6.90 (2H, d, J = 9)
H ₂), 7.43 (2H, d, J = 9H₂)

[0055]

[Chemical 40]

Compound 4 700 mg (2.14 × 10 ^-3
(mol) is dissolved in 15 ml of anhydrous THF and cooled to -68 ° C. 1.4 ml of 1.6 N n-BuLi hexane solution was added dropwise thereto, and the mixture was stirred as it was for 1.5 hours. To this, 0.16 ml (0.226 g) of perfluorocyclopentene was added in two portions, and the mixture was allowed to stand and the temperature was slowly raised to room temperature. This was extracted with water and ether, the ether layer was dried over MgSO ₄ and evaporated, and the residue was purified by silica gel chromatography (hexane) to obtain 170 mg of compound 5 . (Yield 27%)

[0057]

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Melting point: 124-127 ° C. MS: M ⁺ 580 ¹ H-NMRδ 1.82 (6H, s, Me × 2),
3.84 (6H, s, MeO ⁻ × 2), 6.89 (2
H, s, ArH × 2), 6.95 (4H, d, J = 8H
₂ ), 7.52 (4H, d, J = 8H ₂ )

Optical recording method A solution having an absorption maximum at 383 nm obtained by dissolving the compound synthesized above in hexane at 10 ⁻⁴ mol / l was sealed in a glass cell of 1 cm × 1 cm × 4 cm, When this was irradiated with 400 nm monochromatic light for 2 minutes, 29
The absorption at 0 nm was increased. The change in the absorption spectrum is shown in FIG. The change of → in the following formula occurred by irradiation with light of 400 nm.

[0060]

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This closed state is thermally very stable,
No change was observed even after heating at 80 ° C. for 12 hours or more. Next, when the glass cell is irradiated with light of 290 nm, the intensity of this absorption band is reduced and 383 nm is emitted.
Absorption increased and returned to the original absorption spectrum. This change could be reversibly repeated 100 times or more.

Example 2 Production Example of Compound

[0063]

[Chemical 43]

4.52 g of magnesium (0.
186 mol) was added and the atmosphere was replaced with nitrogen, and then anhydrous ether was added. 26.4 g of iodomethane (0.186 mo
The ether solution of 1) was added dropwise and heated under reflux for 30 minutes to prepare a reagent. In a separate flask under a nitrogen atmosphere, dichloro [1,3-bis [diphenylphosphino) propane]
0.50 g (0.93 mmol) of nickel (II), 3,
615 g (62 mmol) of 4-dibromothiophene and anhydrous ether were added, and after cooling to 0 ° C., the reagent adjusted as above was added dropwise and heated under reflux for 20 hours. The reaction solution was poured into ice water, extracted with ether, and then distilled under reduced pressure (67 ° C., 62 mmHg) to obtain 3.65 g (32.5 mmol) of compound 7 . (Yield 52%).

Compound 7 ¹ HNMR (CDCl ₃ , TMS) δ = 2.16 (6H, s, 3,4-Me) 6.88 (2H, s, 2,5-H)

Compound 7 1.8 g (16.0 mmol)
Was dissolved in anhydrous ether under a nitrogen atmosphere. 1.6N n-butyllithium hexane solution 10.5m
1 (16.8 mmol) was slowly added dropwise, and the mixture was heated under reflux for 1 hour. After cooling this to -60 ° C, 0.5 ml of perfluorocyclopentene was added and stirred for 30 minutes, then 0.45 ml of perfluorocyclopentene (total 0.95 m
1, 7.2 mmol) was added and the mixture was stirred as it was overnight.
The mixture was added with water and hydrochloric acid, extracted with ether, dried over magnesium sulfate, and purified by silica gel column cumulography. Yield of compound 8 1.85 g (4.67)
mmol). (Yield 58%).

Compound 8 ¹ HNMR (CDCl ₃ , TMS) δ = 1.63 (3H, s, 4-Me) 2.08 (3H, s, 3-Me) 7.21 (1H, s, 5-H) )

Compound 8 1.85 g (4.74 mmo
l) carbon tetrachloride 15 ml, acetic acid 15 ml, iodic acid 4
A 17 mg (2.37 mmol) aqueous solution was added and stirred. To this, 1.2 g (4.74 mmol) of iodine was added, and the mixture was heated under reflux for 4 hours. After neutralizing the solution, an aqueous sodium thiosulfate solution was added, the mixture was extracted with chloroform, and dried over magnesium sulfate. Yield of compound 9 3.04 g (4.
68 mmol). (Yield 99%).

Compound 9 ¹ HNMR (CDCl ₃ , TMS) δ = 1.74 (3H, s, 4-Me) 2.10 (3H, s, 3-Me)

323 mg of thiophene under nitrogen atmosphere
(3.85 mmol) was dissolved in 10 ml of anhydrous ether, and a 1.6N n-butyllithium hexane solution 2.3 was dissolved.
ml (3.70 mmol) was added, and the mixture was heated under reflux for 1 hr. 1N zinc chloride tetrahydrofuran solution was added to this 4.
0 ml (4.0 mmol) was added, and the mixture was further stirred at room temperature for 3 hours to prepare a reagent. In another flask under nitrogen atmosphere,
27 mg (0.02 mmol) of tetrakis (triphenylphosphine) palladium (0) and compound 923m
g (0.77 mmol) of anhydrous tetrahydrofuran 5m
The resulting solution was added to the above solution, heated under reflux for 3 hours, and stirred overnight at room temperature. Water and hydrochloric acid were added, the mixture was extracted with ether, and dried over magnesium sulfate. Yield of compound 10 228 mg (0.41 mmol). (Yield 53%).

Compound 10 ¹ HNMR (CDCl ₃ , TMS) δ = 1.76 (3H, s, 4-Me) 2.27 (3H, s, 3-Me) 7.21-7.41 (3H, m) , Ar-H)

Optical recording method In the same manner as in Example 1, a hexane solution of the obtained compound 10 having an absorption maximum wavelength of 377 nm was sealed in a glass cell, and this glass cell was irradiated with monochromatic light of 377 nm for 2 minutes. The open ring was converted to the closed ring. This closed state was thermally very stable. Next, when a mercury lamp and a filter were combined and irradiated with monochromatic light of 300 nm for 5 minutes, the original ring-opened body immediately returned. This change could be reversibly repeated. FIG. 2 shows the spectrum change in the ring-opened and ring-closed states.

Example 3 In the same manner as in Example 1, the following compound was synthesized.

[Chemical 44] The obtained compound has an absorption maximum at 380 nm in hexane. This solution was sealed in a glass cell, and the glass cell was irradiated with monochromatic light of 380 nm for 2 minutes, whereby the ring-opened body was converted to the ring-closed body. This ring-closed state was thermally extremely stable. Next, when it was irradiated with monochromatic light of 275 nm for 5 minutes, it immediately returned to the original ring-opened body. This change
It could be reversibly repeated. FIG. 3 shows the spectrum change in the ring-opened and ring-closed states.

[0074]

As described in detail above, the optical recording material of the present invention contains in its recording layer a compound exhibiting good photochromism, and the optical recording material of the present invention comprises:
It is thermally stable, does not show thermochromism, changes its absorption maximum upon irradiation with light, and this ring-closed state is extremely stable thermally, but it returns to its original state when irradiated with light of another wavelength. Thus, this change can be reversibly repeated. Thus, the optical recording material of the present invention, which is a reversible recording material capable of recording in the photon mode, has all the requirements such as semiconductor laser sensitivity, nondestructive read-out, thermal stability of recording, fast response speed, and repeated durability. It is sufficiently satisfactory and has remarkably excellent properties.

[Brief description of drawings]

FIG. 1 is a view showing a light change in absorption spectrum of a compound of the present invention in an optical recording material prepared in Example 1.

FIG. 2 is a view showing a light change in absorption spectrum of the compound of the present invention in the optical recording material prepared in Example 2.

FIG. 3 is a view showing a light change in absorption spectrum of the compound of the present invention in the optical recording material prepared in Example 3.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C07D 307/42 C07D 307/42 333/12 333/12 333/18 333/18 333/24 333 / 24 333/28 333/28 333/36 333/36 333/38 333/38 333/48 333/48 333/54 333/54 333/74 333/74 345/00 345/00 409/08 307 409/08 307 409/14 207 409/14 207 215 215 307 307 417 414/14 207 417/14 207 277 277 333 333 333 487/04 04 140 9271-4C 487/04 140 495/04 101 495/04 101 105 105A 519/00 519 / 00 C09K 9/02 C09K 9/02 B G03C 1/73 503 G03C 1/73 503 G11B 7/24 516 8721-5D G11B 7/24 516 // (C07D 409/08 307: 38 333: 16)

Claims (4)

[Claims] 1. A diarylethene-based photochromic compound represented by the following general formula (I): Embedded image (In the formula, ring B represents a hydrocarbon ring or a heterocycle, and And Y and Y ′ each independently represent a nitrogen atom or a carbon atom, —R represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group, and on ring C and ring D Carbon atoms in the ring have substituents or are joined with adjacent carbon atoms on the same ring to form rings fused to these rings. ) 2. The diarylethene photochromic compound according to claim 1, which is represented by the following general formula (II). Embedded image (In the formula, ring B represents a hydrocarbon ring or a heterocycle, and Wherein Y and Y ′ each independently represent a nitrogen atom or a carbon atom, —R represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group, and —R ⁸ and —R ⁹ represents an optionally substituted hydrocarbon aromatic ring or heteroaromatic ring, wherein carbon atoms on ring C and ring D have a substituent or are taken together with an adjacent carbon atom on the same ring, It forms a ring that is fused to the ring. ) 3. An optical recording material having a recording layer for recording optical information by changing its optical properties upon irradiation with light, wherein the recording layer contains a diarylethene photochromic compound represented by the following general formula (I). An optical recording material characterized by: Embedded image (In the formula, ring B represents a hydrocarbon ring or a heterocycle, and And Y and Y ′ each independently represent a nitrogen atom or a carbon atom, —R represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group, and on ring C and ring D Carbon atoms in the ring have substituents or are joined with adjacent carbon atoms on the same ring to form rings fused to these rings. ) 4. A diarylethene-based photochromic compound has the following general formula (III): (In the formula, ring B represents a hydrocarbon ring or a heterocycle, and Represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group,
^{R 1, -R 2, -R 4} , -R 12 and -R ¹³ each independently represents an alkyl group, a halogen atom or a trifluoromethyl group. ) Or the following general formula [IV] (Wherein, ring A, ring A ′ and ring B represent a hydrocarbon ring or a heterocycle, Represents a hydrogen atom, an optionally substituted alkyl group, an aryl group or a cycloalkyl group, and -R ⁵
And -R ⁶ each independently represents an alkyl group, a halogen atom or a trifluoromethyl group. ) The optical recording material according to claim 1, which is represented by