JP2008120074A - Optical recording material using optical isomer of cyanine compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical recording material using a cyanine compound, which exhibits thermal decomposition behavior suitable for high speed optical recording application and having high solubility. <P>SOLUTION: The optical recording material comprises (A) a cyanine compound expressed by formula (I) and composed of a single substance or a mixture of the isomer excluding at least one or more of the optical isomers, which make an asymmetric atom expressed in * in the formula (I) a chiral center, and (B) a solvent. In the formula (I), a ring A and a ring B independently represent a benzene ring or a naphthalene ring which may have a substituent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical recording material used for an optical recording medium for recording mainly by providing information as an information pattern by a laser or the like, and more specifically, a laser having a wavelength in the ultraviolet and visible regions and a low energy laser or the like. The present invention relates to an optical recording material used for an optical recording medium capable of high-density optical recording and reproduction by the above.

  Optical recording media are generally widespread because they have excellent characteristics such as a large recording capacity and non-contact recording or reproduction. In a write-once optical disk such as WORM, CD-R, DVD ± R, etc., the laser is focused on a very small area of the recording layer, and recording is performed by changing the properties of the optical recording layer. Playback is performed by the difference.

  The optical recording layer of an optical recording medium typified by an optical disc is easy to form an optical recording layer, so organic dyes are used. Especially, cyanine compounds have high sensitivity and can cope with high speed. Has been studied from.

  High-speed recording requires low thermal interference, and suitable optical recording materials include those having a low decomposition temperature and those having a sharp thermal decomposition. For example, Patent Documents 1 to 3 disclose optical recording materials using cyanine compounds that exhibit thermal decomposition behavior suitable for high-speed recording.

  However, each of the cyanine compounds reported above has a problem that a sufficient margin for solubility cannot be obtained and a stable process cannot be provided in the film forming process.

JP 2005-132055 A Japanese Patent No. 3659922 Japanese Patent No. 3698708

  Accordingly, an object of the present invention is to provide an optical recording material using a cyanine-based compound that exhibits thermal decomposition behavior suitable for high-speed optical recording applications and has high solubility.

  As a result of repeated studies, the present inventors have found that a specific optical isomer of a cyanine compound can solve the above problems, and have reached the present invention.

  That is, the present invention relates to (i) a cyanine compound represented by the above general formula (I), wherein at least one optical isomer having an asymmetric atom represented by * in the general formula (I) as a chiral center. The above object has been achieved by providing an optical recording material comprising a single or mixture of isomers excluding two or more and (b) a solvent.

（式中、環Ａ及び環Ｂは、それぞれ独立に、置換基を有してもよいベンゼン環又はナフタレン環を表し、Ｒ¹は、下記一般式（II）又は（II’）で表される基を表し、Ｒ²は、下記一般式（II）、（II’）、（III）で表される基又は炭素原子数１〜３０の有機基を表す。但し、Ｒ¹とＲ²は同一の基を表さない。Ｒ³及びＲ⁴は、それぞれ独立に、下記一般式（II）、（II’）、（III）で表される基、炭素原子数１〜３０の有機基又は連結して３〜６員環を形成する基を表し、Ｙ¹及びＹ²は、それぞれ独立に、炭素原子数１〜３０の有機基又は下記一般式（III）で表される基を表し、Ｌは、鎖中に環構造を含んでもよいポリメチン鎖を表し、該ポリメチン鎖中の水素原子は、ハロゲン原子、シアノ基、水酸基、アルキル基、アルコキシ基又はアリール基で置換されていてもよく、該アルキル基、該アルコキシ基及び該アリール基はさらに置換されていてもよい。Ａｎ^m-は、ｍ価のアニオンを表し、ｍは、１又は２であり、ｐは、電荷を中性に保つ係数を表す。）

(In the formula, ring A and ring B each independently represent an optionally substituted benzene ring or naphthalene ring, and R ¹ is represented by the following general formula (II) or (II ′)). R ² represents a group represented by the following general formulas (II), (II ′) and (III) or an organic group having 1 to 30 carbon atoms, provided that R ¹ and R ² are the same. R ³ and R ⁴ are each independently a group represented by the following general formulas (II), (II ′), (III), an organic group having 1 to 30 carbon atoms, or a linkage. And Y ¹ and Y ² each independently represents an organic group having 1 to 30 carbon atoms or a group represented by the following general formula (III), L Represents a polymethine chain which may contain a ring structure in the chain, and the hydrogen atom in the polymethine chain is a halogen atom, a cyano group, a hydroxyl group, an alkyl group, an alkoxy group or an aryl group. The alkyl group, the alkoxy group, and the aryl group may be further substituted, An ^m- represents an m-valent anion, m is 1 or 2, and p is , Represents the coefficient to keep the charge neutral.)

（上記一般式（II）において、ＧとＴの間の結合は二重結合、共役二重結合又は三重結合であり、Ｇは炭素原子を表し、Ｔは炭素原子、酸素原子又は窒素原子を表し、ｗは０〜４の数を表し、ｘ、ｙ及びｚは０又は１を表し（ただし、Ｔが酸素原子である場合はｙとｚは０であり、Ｔが窒素原子である場合はｙ＋ｚは０又は１である。）、Ｒ⁰¹、Ｒ⁰²、Ｒ⁰³及びＲ⁰⁴は、それぞれ独立に、水素原子、水酸基、シアノ基、ニトロ基、ハロゲン原子又は置換基を有していてもよい炭素原子数１〜４のアルキル基を表し、該アルキル基中のメチレン基は、−Ｏ−又は−ＣＯ−で置換されていてもよく、Ｒ⁰¹とＲ⁰⁴は、結合してシクロアルケン環又は複素環を形成してもよい。上記一般式（II’）において、Ｇ’とＴ’の間の結合は二重結合又は共役二重結合であり、Ｇ’は炭素原子を表し、Ｔ’は炭素原子又は窒素原子を表し、ｗ’は０〜４の数を表し、Ｒ^01'は、水素原子、水酸基、シアノ基、ニトロ基、ハロゲン原子又は置換基を有していてもよい炭素原子数１〜４のアルキル基を表し、該アルキル基中のメチレン基は、−Ｏ−又は−ＣＯ−で置換されていてもよく、Ｇ’及びＴ’を含む環は、ヘテロ原子を含んでもよい５員環、ヘテロ原子を含んでもよい６員環、ナフタレン環、キノリン環、イソキノリン環、アントラセン環又はアントラキノン環を表し、これらＧ’及びＴ’を含む環は、ハロゲン原子、ニトロ基、シアノ基、アルキル基又はアルコキシ基で置換されていてもよい。）

(In the above general formula (II), the bond between G and T is a double bond, a conjugated double bond or a triple bond, G represents a carbon atom, and T represents a carbon atom, an oxygen atom or a nitrogen atom. , W represents a number from 0 to 4, x, y and z represent 0 or 1 (provided that when T is an oxygen atom, y and z are 0, and when T is a nitrogen atom, y + z) Is 0 or 1.), R ⁰¹ , R ⁰² , R ⁰³ and R ⁰⁴ are each independently a hydrogen atom, a hydroxyl group, a cyano group, a nitro group, a halogen atom or a carbon which may have a substituent. Represents an alkyl group having 1 to 4 atoms, and the methylene group in the alkyl group may be substituted with —O— or —CO—, and R ⁰¹ and R ⁰⁴ may be bonded to form a cycloalkene ring or a heterocycle; In the above general formula (II ′), the bond between G ′ and T ′ is a double bond or a conjugated double bond. A case, G 'represents a carbon atom, T' represents a carbon atom or a nitrogen atom, w 'represents a number from 0 to 4, R ^01' represents a hydrogen atom, a hydroxyl group, a cyano group, a nitro group, Represents a halogen atom or an optionally substituted alkyl group having 1 to 4 carbon atoms, and the methylene group in the alkyl group may be substituted with —O— or —CO—, and G ′ And a ring containing T ′ represents a 5-membered ring which may contain a heteroatom, a 6-membered ring which may contain a heteroatom, a naphthalene ring, a quinoline ring, an isoquinoline ring, an anthracene ring or an anthraquinone ring. The ring containing 'may be substituted with a halogen atom, a nitro group, a cyano group, an alkyl group or an alkoxy group.)

（式中、Ｒ^a〜Ｒⁱは、それぞれ独立に、水素原子又は炭素原子数１〜４のアルキル基を表し、該アルキル基中のメチレン基は、−Ｏ−又は−ＣＯ−で置換されていてもよく、Ｑは、直接結合又は置換基を有してもよい炭素原子数１〜８のアルキレン基を表し、該アルキレン基中のメチレン基は、−Ｏ−、−Ｓ−、−ＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＳＯ₂−、−ＮＨ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−Ｎ＝ＣＨ−又は−ＣＨ＝ＣＨ−で置換されていてもよく、Ｍは、Ｆｅ、Ｃｏ、Ｎｉ、Ｔｉ、Ｃｕ、Ｚｎ、Ｚｒ、Ｃｒ、Ｍｏ、Ｏｓ、Ｍｎ、Ｒｕ、Ｓｎ、Ｐｄ、Ｒｈ、Ｐｔ又はＩｒを表す。）

(Wherein R ^{a to} R ⁱ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the methylene group in the alkyl group is substituted with —O— or —CO—). Q represents an alkylene group having 1 to 8 carbon atoms which may have a direct bond or a substituent, and the methylene group in the alkylene group is -O-, -S-, -CO-. , —COO—, —OCO—, —SO ₂ —, —NH—, —CONH—, —NHCO—, —N═CH— or —CH═CH—, where M is Fe, (Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, Pt, or Ir are represented.)

  In addition, the present invention achieves the above object by providing an optical recording medium having an optical recording layer formed of the above optical recording material on a substrate.

  According to the present invention, an optical recording material suitable for forming an optical recording layer of an optical recording medium can be provided. Since the specific cyanine compound according to the present invention has a low decomposition point, heat storage is low and thermal interference is suppressed, and since the solubility is high, workability is high and the solvent can be used at a high concentration, so that the amount of solvent used is low. The amount is small and suitable for forming an optical recording layer of an optical recording medium.

Hereinafter, the optical recording material of the present invention will be described in detail based on preferred embodiments.
First, the cyanine compound represented by the general formula (I) will be described.

Organic group having 1 to 30 carbon atoms other than the general formula (II), (II ′) or (III) represented by R ² , R ³ , R ⁴ , Y ¹ and Y ² in the general formula (I) Is not particularly limited, for example, methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, isobutyl, amyl, isoamyl, t-amyl, hexyl, cyclohexyl, cyclohexylmethyl, 2-cyclohexylethyl, Alkyl groups such as heptyl, isoheptyl, t-heptyl, n-octyl, isooctyl, t-octyl, 2-ethylhexyl, nonyl, isononyl, decyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, peptadecyl, octadecyl; vinyl, 1- Methylethenyl, 2-methylethenyl, propenyl, butenyl, isobutenyl, Alkenyl groups such as nthenyl, hexenyl, heptenyl, octenyl, decenyl, pentadecenyl, 1-phenylpropen-3-yl; phenyl, naphthyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-vinylphenyl, 3-isopropylphenyl, 4-isopropylphenyl, 4-butylphenyl, 4-isobutylphenyl, 4-t-butylphenyl, 4-hexylphenyl, 4-cyclohexylphenyl, 4-octylphenyl, 4- (2-ethylhexyl) phenyl 4-stearylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2, 4-di-t-butylphenyl, cycl Alkylaryl groups such as hexylphenyl; arylalkyl groups such as benzyl, phenethyl, 2-phenylpropan-2-yl, diphenylmethyl, triphenylmethyl, styryl, cinnamyl, and their hydrocarbon groups interrupted by an ether bond or thioether bond Such as 2-methoxyethyl, 3-methoxypropyl, 4-methoxybutyl, 2-butoxyethyl, methoxyethoxyethyl, methoxyethoxyethoxyethyl, 3-methoxybutyl, 2-phenoxyethyl, 2-methylthioethyl, 2-phenylthioethyl is mentioned, and these groups may be further substituted with an alkoxy group, an alkenyl group, a nitro group, a cyano group, a halogen atom or the like.
Examples of the ring structure in which R ³ and R ⁴ are linked to form a 3- to 6-membered ring include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring.

  As the polymethine chain which may contain a ring structure in the chain represented by L in the general formula (I), groups represented by the following general formulas (1) to (10) are preferable, and the following general formula (1) The groups represented by (4) and (7) are more preferred.

（式中、Ｒ⁷、Ｒ⁸、Ｒ⁹、Ｒ¹⁰、Ｒ¹¹及びＲ¹²は、それぞれ独立に、水素原子、水酸基、ハロゲン原子、シアノ基、炭素原子数６〜３０のアリール基、ジフェニルアミノ基、炭素原子数１〜８のアルキル基又は炭素原子数１〜８のアルコキシ基を表し、Ｅは、水素原子、ハロゲン原子、シアノ基、水酸基、アルキル基、アルコキシ基又はアリール基を表し、該アルキル基、該アルコキシ基及び該アリール基は置換基を有していてもよい。）

(Wherein R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are each independently a hydrogen atom, a hydroxyl group, a halogen atom, a cyano group, an aryl group having 6 to 30 carbon atoms, or diphenylamino. Group, an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms, E represents a hydrogen atom, a halogen atom, a cyano group, a hydroxyl group, an alkyl group, an alkoxy group or an aryl group; (The alkyl group, the alkoxy group and the aryl group may have a substituent.)

Examples of the substituents on the benzene ring and naphthalene ring represented by ring A or ring B in the general formula (I) include the following.
Examples of the substituent include methyl, ethyl, propyl, isopropyl, cyclopropyl, butyl, s-butyl, t-butyl, isobutyl, amyl, isoamyl, t-amyl, cyclopentyl, hexyl, 2-hexyl, and 3-hexyl. , Alkyl groups such as cyclohexyl, bicyclohexyl, 1-methylcyclohexyl, heptyl, 2-heptyl, 3-heptyl, isoheptyl, t-heptyl, n-octyl, isooctyl, t-octyl, 2-ethylhexyl, nonyl, isononyl, decyl Methyloxy, ethyloxy, propyloxy, isopropyloxy, butyloxy, s-butyloxy, t-butyloxy, isobutyloxy, amyloxy, isoamyloxy, t-amyloxy, hexyloxy, cyclohexyloxy, Alkoxy groups such as tiloxy, isoheptyloxy, t-heptyloxy, n-octyloxy, isooctyloxy, t-octyloxy, 2-ethylhexyloxy, nonyloxy, decyloxy; methylthio, ethylthio, propylthio, isopropylthio, butylthio, s -Butylthio, t-butylthio, isobutylthio, amylthio, isoamylthio, t-amylthio, hexylthio, cyclohexylthio, heptylthio, isoheptylthio, t-heptylthio, n-octylthio, isooctylthio, t-octylthio, 2-ethylhexylthio, etc. Alkylthio group; vinyl, 1-methylethenyl, 2-methylethenyl, 2-propenyl, 1-methyl-3-propenyl, 3-butenyl, 1-methyl-3-butenyl, isobutenyl , Alkenyl groups such as 3-pentenyl, 4-hexenyl, cyclohexenyl, bicyclohexenyl, heptenyl, octenyl, decenyl, pentadecenyl, eicosenyl, tricosenyl; arylalkyls such as benzyl, phenethyl, diphenylmethyl, triphenylmethyl, styryl, cinnamyl Groups; aryl groups such as phenyl and naphthyl; aryloxy groups such as phenoxy and naphthyloxy; arylthio groups such as phenylthio and naphthylthio; Benzimidazolyl, triazolyl, furyl, furanyl, benzofuranyl, thienyl, thiophenyl, benzothiophenyl, thiadiazolyl, thiazolyl, Benzothiazolyl, oxazolyl, benzoxazolyl, isothiazolyl, isoxazolyl, indolyl, 2-pyrrolidinon-1-yl, 2-piperidone-1-yl, 2,4-dioxyimidazolidin-3-yl, 2,4-dioxy Heterocyclic groups such as oxazolidin-3-yl; halogen atoms such as fluorine, chlorine, bromine, iodine; acetyl, 2-chloroacetyl, propionyl, octanoyl, acryloyl, methacryloyl, phenylcarbonyl (benzoyl), phthaloyl, 4-trifluoro Acyl groups such as methylbenzoyl, pivaloyl, salicyloyl, oxaloyl, stearoyl, methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, n-octadecyloxycarbonyl, carbamoyl; acetyloxy, benzoylo An acyloxy group such as amino; amino, ethylamino, dimethylamino, diethylamino, butylamino, cyclopentylamino, 2-ethylhexylamino, dodecylamino, anilino, chlorophenylamino, toluidino, anisidino, N-methyl-anilino, diphenylamino, naphthylamino; 2-pyridylamino, methoxycarbonylamino, phenoxycarbonylamino, acetylamino, benzoylamino, formylamino, pivaloylamino, lauroylamino, carbamoylamino, N, N-dimethylaminocarbonylamino, N, N-diethylaminocarbonylamino, morpholinocarbonylamino , Methoxycarbonylamino, ethoxycarbonylamino, t-butoxycarbonylamino, n-octadecyloxycarbo Substituted amino groups such as ruamino, N-methyl-methoxycarbonylamino, phenoxycarbonylamino, sulfamoylamino, N, N-dimethylaminosulfonylamino, methylsulfonylamino, butylsulfonylamino, phenylsulfonylamino; sulfonamide group, sulfonyl Group, carboxyl group, cyano group, sulfo group, hydroxyl group, nitro group, mercapto group, trialkylsilyl group, imide group, carbamoyl group, sulfonamide group and the like, and these groups may be further substituted. Further, the carboxyl group and the sulfo group may form a salt, complex or complex with an inorganic base or organic base.

In the general formula (I), the anion represented by An ^m- is, for example, a monovalent halogen anion such as chloride ion, bromide ion, iodide ion or fluoride ion; perchlorate ion Inorganic ions such as chlorate ion, thiocyanate ion, hexafluorophosphate ion, hexafluoroantimonate ion, tetrafluoroborate ion; benzenesulfonate ion, toluenesulfonate ion, trifluoromethanesulfonate ion, diphenylamine- Organic sulfones such as 4-sulfonic acid ion, 2-amino-4-methyl-5-chlorobenzenesulfonic acid ion, 2-amino-5-nitrobenzenesulfonic acid ion, N-alkyl (or aryl) diphenylamine-4-sulfonic acid ion Acid anion; octyl Organophosphates such as phosphate ion, dodecyl phosphate ion, octadecyl phosphate ion, phenyl phosphate ion, nonylphenyl phosphate ion, 2,2′-methylenebis (4,6-di-t-butylphenyl) phosphonate ion System anion, bistrifluoromethylsulfonylimide ion, bisperfluorobutanesulfonylimide ion, perfluoro-4-ethylcyclohexanesulfonate ion, tetrakis (pentafluorophenyl) borate ion, tris (fluoroalkylsulfonyl) carboanion Examples of the divalent compounds include benzene disulfonate ion and naphthalenedisulfonate ion. In addition, quencher anions that have the function of de-exciting (quenching) active molecules in the excited state and ferrocene and ruthenocene having an anionic group such as a carboxyl group, a phosphonic acid group, and a sulfonic acid group on the cyclopentadienyl ring. A metallocene compound anion such as can also be used as necessary. Also, p is selected so that the charge is neutral throughout the molecule.

  Examples of the quencher anion include those represented by the following general formula (A) or (B), the following chemical formula (C) or (D), JP-A-60-234892, JP-A-5-43814. JP-A-5-305770, JP-A-6-239028, JP-A-9-309886, JP-A-9-323478, JP-A-10-45767, JP-A-11-208118 JP-A-2000-168237, JP-A-2002-201373, JP-A-2002-206061, JP-A-2005-297407, JP-B-7-96334, WO98 / 29257, etc. Anions as described are mentioned.

（式中、Ｍは、上記一般式（III）と同じであり、Ｒ¹³及びＲ¹⁴は、それぞれ独立に、ハロゲン原子、炭素原子数１〜８のアルキル基、炭素原子数６〜３０のアリール基又は−ＳＯ₂−Ｊ基を表し、Ｊは、アルキル基、ハロゲン原子で置換されていてもよいアリール基、ジアルキルアミノ基、ジアリールアミノ基、ピペリジノ基又はモルフォリノ基を表し、ａ及びｂは、各々独立に、０〜４の数を表す。また、Ｒ¹⁵、Ｒ¹⁶、Ｒ¹⁷及びＲ¹⁸は、それぞれ独立に、アルキル基、アルキルフェニル基、アルコキシフェニル基又はハロゲン化フェニル基を表す。）

(In the formula, M is the same as in the general formula (III), and R ¹³ and R ¹⁴ are each independently a halogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl having 6 to 30 carbon atoms. represents a group or -SO ₂ -J group, J is an alkyl group, an aryl group which may be substituted by a halogen atom, a dialkylamino group, a diarylamino group, a piperidino group or a morpholino group, a and b, Each independently represents a number from 0 to 4. R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represents an alkyl group, an alkylphenyl group, an alkoxyphenyl group or a halogenated phenyl group.

Examples of the halogen atom represented by R ⁰¹ , R ⁰² , R ⁰³ , R ^{04 in the} general formula (II) and R ^{01 ′} in the general formula (II ′) include fluorine, chlorine, bromine, iodine and the like. The alkyl group having 1 to 4 carbon atoms represented by R ⁰¹ , R ⁰² , R ⁰³ , R ^{04 in the} general formula (II) and R ^{01 ′} in the general formula (II ′) includes methyl, ethyl , Propyl, isopropyl, butyl, s-butyl, t-butyl, isobutyl and the like. Examples of the group in which the methylene group in the alkyl group is substituted with -O- include methoxy, ethoxy, propyloxy, isopropyloxy, Examples of the group in which the methylene group in the alkyl group is substituted with -CO- include acetyl, 1-carbonylethyl, acetylmethyl, 1-methyl and the like. Rubonirupuropiru, 2-oxobutyl, 2-acetylethyl, 1-carbonyl-isopropyl and the like, any of which may have a substituent. Examples of the cycloalkene ring formed by combining R ⁰¹ and R ⁰⁴ include a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, a cyclohexadiene ring, and the like, and a complex formed by combining R ⁰¹ and R ^04. Examples of the ring include dihydropyran ring, pyrroline ring, pyrazoline ring, indoline ring, pyrrole ring, thiophene ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, quinoline ring, isoquinoline ring, imidazole ring, oxazole And a ring, an imidazolidine ring, a pyrazolidine ring, an isoxazolidine ring, an isothiazolidine ring, and the like. These rings may be condensed or substituted with other rings. R ⁰¹ , R ⁰² , R ⁰³ , R ^{04 in the} general formula (II) and an alkyl group having 1 to 4 carbon atoms represented by R ^{01 ′} in the general formula (II ′), the general formula (II) Examples of the substituent of the ring structure formed by linking R ⁰¹ and R ⁰⁴ in are those exemplified in the description of the general formula (I). R ⁰¹ , R ⁰² , R ⁰³ , R ⁰⁴ and R ^{01 ′} are the above-described alkyl groups having 1 to 4 carbon atoms, and among the following substituents, have a substituent containing a carbon atom. In this case, the total number of carbon atoms such as R ⁰¹ including the substituent should satisfy the specified range.

  In the general formula (II ′), examples of the 5-membered ring that may contain a hetero atom include a cyclopentene ring, cyclopentadiene ring, imidazole ring, thiazole ring, pyrazole ring, oxazole ring, isoxazole ring, thiophene ring, and furan ring. Examples of the 6-membered ring that may contain a hetero atom include a benzene ring, a pyridine ring, a piperazine ring, a piperidine ring, a morpholine ring, a pyrazine ring, a pyrone ring, and a pyrrolidine ring. .

Examples of the alkyl group having 1 to 4 carbon atoms represented by R ^{a to} R ⁱ in the general formula (III) include those exemplified in the description of the general formula (II), and methylene in the alkyl group Examples of the group substituted with —O— include methoxy, ethoxy, propyloxy, isopropyloxy, methoxymethyl, ethoxymethyl, 2-methoxyethyl, etc., and the methylene group in the alkyl group is —CO—. Examples of the substituted group include acetyl, 1-carbonylethyl, acetylmethyl, 1-carbonylpropyl, 2-oxobutyl, 2-acetylethyl, 1-carbonylisopropyl and the like.

Examples of the alkylene group having 1 to 8 carbon atoms which may have a substituent represented by Q in the general formula (III) include methylene, ethylene, propylene, methylethylene, butylene, 1-methylpropylene, 2- Methylpropylene, 1,2-dimethylpropylene, 1,3-dimethylpropylene, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, 4-methylbutylene, 2,4-dimethylbutylene, 1,3-dimethylbutylene , Pentylene, hexylene, heptylene, octylene, ethane-1,1-diyl, propane-2,2-diyl and the like, and the methylene group in the alkylene group is -O-, -S-, -CO-, -COO -, - OCO -, - SO 2 -, - NH -, - CONH -, - NHCO -, - N = CH- or substituted with -CH = CH- Examples of the group include methyleneoxy, ethyleneoxy, oxymethylene, thiomethylene, carbonylmethylene, carbonyloxymethylene, methylenecarbonyloxy, sulfonylmethylene, aminomethylene, acetylamino, ethylenecarboxyamide, etanimidyl, ethenylene, propenylene, and the like. .
Examples of the substituent of the alkylene group having 1 to 8 carbon atoms represented by Q in the general formula (III) include those exemplified in the description of the general formula.

  The cyanine compound according to the present invention is preferably a compound represented by the following general formula (IV) because of its low production cost and high solubility in a coating solvent as an optical recording material. Among these compounds, the compounds represented by the following general formula (V) or (VII) are preferable because they are particularly excellent in thermal decomposition behavior and can be used as a high-definition recording medium.

（式中、環Ａ、Ｒ¹、Ｒ²、Ｙ¹、Ｌ、Ａｎ^m-、ｍ、ｐは、上記一般式（Ｉ）と同じである。）

(In the formula, ring A, R ¹ , R ² , Y ¹ , L, An ^m− , m, and p are the same as those in the general formula (I).)

（式中、環Ａ、Ｙ¹、Ａｎ^m-、ｍ、ｐは、上記一般式（Ｉ）と同じであり、Ｒ⁵¹は下記一般式（VI）で表される基であり、Ｒ⁵²はＲ⁵¹とは異なる上記一般式（II）、（II’）、（III）で表される基又は炭素原子数１〜３０の有機基である。）

(In the formula, ring A, Y ¹ , An ^m− , m, and p are the same as in the above general formula (I), R ⁵¹ is a group represented by the following general formula (VI), and R ⁵² is It is a group represented by the above general formulas (II), (II ′) and (III) different from R ⁵¹ or an organic group having 1 to 30 carbon atoms.

（式中、Ｒ⁰¹、Ｒ⁰²、Ｒ⁰³及びＲ⁰⁴は、上記一般式（II）と同じである。）

(In the formula, R ⁰¹ , R ⁰² , R ⁰³ and R ⁰⁴ are the same as those in the general formula (II).)

（式中、環Ａ、Ｙ¹、Ａｎ^m-、ｍ、ｐは、上記一般式（Ｉ）と同じであり、Ｒ⁷¹は下記一般式（VIII）で表される基であり、Ｒ⁷²は、Ｒ⁷¹とは異なる上記一般式（II）、（II’）、（III）で表される基又は炭素原子数１〜３０の有機基である。）

(In the formula, rings A, Y ¹ , An ^m− , m, and p are the same as those in the general formula (I), R ⁷¹ is a group represented by the following general formula (VIII), and R ⁷² is And a group represented by the above general formulas (II), (II ′) and (III) different from R ⁷¹ or an organic group having 1 to 30 carbon atoms.

（式中、環Ａ、Ｒ²、Ｙ¹、Ａｎ^m-及びｐは、上記一般式（Ｉ）と同じであり、Ｚは、炭素原子数１〜４のアルキル基を表し、ｎは、０〜５の数である。）

(In the formula, rings A, R ² , Y ¹ , An ^m- and p are the same as those in the general formula (I), Z represents an alkyl group having 1 to 4 carbon atoms, and n is 0. A number of ~ 5.)

  Examples of the alkyl group having 1 to 4 carbon atoms represented by Z in the general formula (VII) include those exemplified in the description of the general formula (II).

  Preferable specific examples of the compound represented by the general formula (I) include the following compound No. 1-34. In the following examples, cyanine cations without anions are shown, and optical isomers are not distinguished. In the cyanine compound according to the present invention, the polymethine chain may have a resonance structure.

  The optical recording material of the present invention is (i) a cyanine compound represented by the above general formula (I), which is an optical isomer having an asymmetric atom represented by * in the general formula (I) as a chiral center. It consists of a simple substance or a mixture of isomers excluding at least one or more and (b) a solvent.

  A specific enantiomer or diastereomer produced by resolving an optical isomer has the effect of suppressing thermal interference more than a whole mixture of enantiomers or the other isomer, and is an optical recording material capable of high-speed recording. The performance of can be demonstrated.

An “enantiomer” is a compound that is a mirror image of a combination, and a “diastereomer” is a compound that is an isomer of a combination that is not a mirror image. For example, when the 3-position of the two heterocycles of ring A and ring B represented by the general formula (I) is an asymmetric carbon, those in which both the asymmetric carbons are in the R-configuration (R, R) -Symbols in which the asymmetric carbon at the 3-position of the heterocyclic ring is both in the S-configuration (S, S) -isomer, those in the R-configuration and S-configuration are in the (R, S) -isomer, S- Arrangements and R-configurations are called (S, R) -forms, (R, R) -forms and (S, S) -forms, (R, S) -forms and (S, R) -forms Are enantiomers, and combinations such as (R, R) -form and (S, R) -form that are not mirror images are diastereomers. In the case of a symmetrical compound as in the general formula (IV), the (R, S) -form and the (S, R) -form are the same compound, which is referred to as a “meso isomer” It is a diastereomer for the (R, R)-and (S, S) -forms.

  Examples of isomers to be removed include (R, S) -isomer (meso isomer) or (R, R) -isomer and (S, S) in the case of a symmetrical compound as in the general formula (IV). ) -Isomers are preferred, and in particular, in the case of the compound represented by the general formula (V) (for example, Compound No. 1), the (R, R) -isomer and the (S, S) -isomer are In addition, it is preferable to use the (R, S) -isomer (meso isomer) because there is little thermal interference. In the case of the compound represented by the general formula (VII) (for example, Compound No. 2), (R , S) -isomers (meso isomers) and a mixture of (R, R) -isomers and (S, S) -isomers are preferred because of less thermal interference.

  Although the manufacturing method of the optical isomer of the cyanine compound represented by the general formula (I) is not particularly limited, for example, Compound No. 1 will be described. As shown in the following [Chemical Formula 17], the indolenine quaternary salt as a raw material and the intermediate obtained by reacting the indolenine quaternary salt with diphenylformamidine are optically resolved by a conventionally known method. It can be obtained by a dyeing reaction by a conventionally known method.

  The solvent (b) used in the optical recording material of the present invention is not particularly limited. For example, lower alcohols such as methanol and ethanol; ether alcohols such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and butyl diglycol; acetone , Ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and diacetone alcohol; esters such as ethyl acetate, butyl acetate and methoxyethyl acetate; acrylic acid esters such as ethyl acrylate and butyl acrylate; , Fluorinated alcohols such as 3-tetrafluoropropanol; hydrocarbons such as benzene, toluene and xylene; chlorinated hydrocarbons such as methylene dichloride, dichloroethane and chloroform. 10-99.99 mass% is preferable in the optical recording material of this invention, and, as for content of the said solvent (b), 90-99 mass% is more preferable.

The optical recording medium of the present invention is obtained by forming an optical recording layer made of the optical recording material on a substrate.
The method for producing the optical recording material of the present invention and the method for producing an optical recording medium characterized by forming an optical recording layer comprising the optical recording material on the substrate of the present invention are not particularly limited. In general, the cyanine compound of the present invention and, if necessary, various compounds described below are dissolved in the above solvent to prepare a solution optical recording material, and the optical recording material is spin-coated, sprayed, dipped, etc. on a substrate. The wet coating method etc. which apply | coat by are used.

  The optical recording layer is formed as a thin film, and the thickness is usually 0.001 to 10 μm, preferably 0.01 to 5 μm.

  In the optical recording material of the present invention, the content of the cyanine compound according to the present invention is preferably 10 to 100% by mass in the solid content contained in the optical recording material of the present invention. The optical recording layer is preferably formed so as to contain 50 to 100% by mass of the cyanine compound in the optical recording layer. In order to form an optical recording layer having such a cyanine compound content, the present invention is used. The optical recording material further preferably contains the cyanine compound in an amount of 50 to 100% by mass based on the solid content contained in the optical recording material of the present invention.

  The solid content contained in the optical recording material of the present invention is a component obtained by removing components other than the solid content such as an organic solvent from the optical recording material, and the content of the solid content is in the optical recording material. 0.01-90 mass% is preferable and 1.0-10 mass% is more preferable.

  In addition to the cyanine compound of the present invention, the optical recording material of the present invention includes, as necessary, an azo compound, a phthalocyanine compound, an oxonol compound, a squarylium compound, an indole compound, a styryl compound, a porphine compound, and azulium. Compounds, croconic methine compounds, pyrylium compounds, thiopyrylium compounds, triarylmethane compounds, diphenylmethane compounds, tetrahydrocholine compounds, indophenol compounds, anthraquinone compounds, naphthoquinone compounds, xanthene compounds, thiazines Compounds commonly used in optical recording layers, such as polyethylene compounds, acridine compounds, oxazine compounds, spiropyran compounds, fluorene compounds, rhodamine compounds; polyethylene, polyester, poly Resins such as Tylene and polycarbonate; surfactants; antistatic agents; lubricants; flame retardants; radical scavengers such as hindered amines; pit formation accelerators such as ferrocene derivatives; dispersants; antioxidants; cross-linking agents; An agent or the like may be contained. Furthermore, the optical recording material of the present invention may contain an aromatic nitroso compound, an aminium compound, an iminium compound, a bisiminium compound, a transition metal chelate compound, or the like as a quencher such as singlet oxygen. In the optical recording material of the present invention, these various compounds are used in an amount ranging from 0 to 50% by mass in the solid content contained in the optical recording material of the present invention.

  The optical recording material of the present invention may contain a diimonium compound. By containing the dimonium compound, it is possible to more effectively prevent a decrease in the residual absorbance with time of the optical recording medium of the present invention. Further, the content when the immonium compound is contained is preferably an amount in the range of 0 to 90% by mass, more preferably 0 to 50% by mass in the solid content contained in the optical recording material of the present invention. .

  The material of the substrate on which such an optical recording layer is provided is not particularly limited as long as it is substantially transparent to writing (recording) light and reading (reproducing) light. For example, polymethyl methacrylate, A resin such as polyethylene terephthalate or polycarbonate, glass, or the like is used. Moreover, the shape can use arbitrary shapes, such as a tape, a drum, a belt, a disk, according to a use.

  On the optical recording layer, a reflective film can be formed by vapor deposition or sputtering using gold, silver, aluminum, copper or the like, and a protective layer is formed by acrylic resin, ultraviolet curable resin, or the like. You can also

  The optical recording material of the present invention is suitable for an optical recording medium using a semiconductor laser for recording and reproduction, and is particularly suitable for a high-speed recording type optical disc such as CD-R and DVD ± R.

Hereinafter, the present invention will be described in more detail with examples, comparative examples, and evaluation examples. However, the present invention is not limited by the following examples.
The following Production Examples 1 to 6 are compound Nos. 1 (R, R) -form, (S, S) -form and (R, S) -form and Compound No. Production examples of (R, R) -form, (S, S) -form and (R, S) -form of Example 2 are shown. 1 (R, S) -isomer, and an equivalent mixture of (R, R) -isomer and (S, S) -isomer (hereinafter referred to as (R, R) (S, S) -isomer), and compound No. Of (R, S) -form and (R, R) (S, S) -form preparation of optical recording material No. 2 and optical recording medium No. 1 using the optical recording material. 1-No. 4 shows an example of production.

  Comparative Example 1 below shows the preparation of a comparative optical recording material using a cyanine compound having a structure different from that of the cyanine compound represented by the general formula (I), and comparative optical recording medium No. 1 using the comparative optical recording material. 1 shows an example of production.

  In the following Evaluation Examples 1-1 to 1-4 and Comparative Evaluation Examples 1-1 to 1-3, Compound No. 1 (R, S) -form and (R, R) (S, S) -form, Compound No. 2 (R, S) -form and (R, R) (S, S) -form and Comparative Compound No. 1 of Comparative Example 1. 1, compound no. The total mixture of isomers of 1 and compound no. The thermal decomposition behavior of the total mixture of the two isomers was evaluated by differential thermal analysis measurement at a heating rate of 10 ° C./min in a nitrogen stream. The results are shown in [Table 1] below.

  In the following evaluation examples 2-1 to 2-4 and comparative evaluation example 2-1, compound no. 1 (R, S) -form and (R, R) (S, S) -form, Compound No. 2 (R, S) -form and (R, R) (S, S) -form and Comparative Compound No. 1 of Comparative Example 1. 1 was evaluated for solubility. The results are shown in [Table 2] below.

[Production Example 1] Compound No. 1 Preparation of (R, R) -form of 1 <Step 1> Synthesis of R-form quaternary salt (PF ₆ salt) 10 g of sodium hydroxide, 121 g of water and 121 g of toluene were charged, and 3-allyl-1, 66.1 g of quaternary salt of 2,3-trimethylbenzoindolenine (bromine anion) was gradually added. Oil / water separation was performed, and washing was performed until the aqueous layer became neutral, and then the solvent was distilled off. To the residue, a solution obtained by dissolving 75.3 g of (−)-dibenzoyltartaric acid in 121 g of ethyl acetate was added dropwise and stirred at 80 ° C. for 1 hour. After cooling to room temperature, the mixture was filtered, and the resulting solid was recrystallized from ethanol to obtain 15.5 g of an R-form quaternary salt (dibenzoyl tartrate anion).
15 g of the obtained R-form quaternary salt (dibenzoyl tartrate anion), 1.25 g of sodium hydroxide, 19.8 g of water and 19.8 g of toluene were charged and stirred at room temperature for 30 minutes. Oil-water separation was performed, and washing was performed until the aqueous layer became neutral. Then, 2.6 g of hydrochloric acid was added to the oil layer and stirred for 1 hour. When 9.20 g of KPF ₆ was dissolved in 19.8 g of water and 19.8 g of ethyl acetate were added, a solid was precipitated. The precipitated solid was collected by filtration and dried to obtain 8 g (yield 21%) of the target R-isomer quaternary salt (PF ₆ salt).

<Step 2> Compound No. Synthesis of 1 (R, R) -isomer 1.19 g of R-isomer quaternary salt (PF ₆ salt) obtained in Step 1, 0.32 g of diphenylformamidine and 1.19 g of pyridine were charged at 50 ° C. Heated for hours. After 1.96 g of acetic anhydride was added dropwise, the mixture was heated at 50 ° C. for 4 hours. Cooled to room temperature and evaporated the solvent. The residue was recrystallized from a mixed solvent of acetone / methanol to obtain the target compound No. 0.4 g (yield 40%) of 1 (R, R) -isomer was obtained. About the obtained compound, when CD spectrum was measured using the circular dichroism dispersometer,-rotation of light was seen and it has confirmed that it was a target object.

[Production Example 2] Compound No. Preparation of 1 (S, S) -isomer <Step 1> Synthesis of S-isomer quaternary salt (PF ₆ salt) 10 g of sodium hydroxide, 121 g of water and 121 g of toluene were charged, and 3-allyl-1, 66.1 g of quaternary salt of 2,3-trimethylbenzoindolenine (bromine anion) was gradually added. Oil / water separation was performed, and washing was performed until the aqueous layer became neutral, and then the solvent was distilled off. To the residue, a solution obtained by dissolving 75.3 g of (+)-dibenzoyltartaric acid in 121 g of ethyl acetate was added dropwise and stirred at 80 ° C. for 1 hour. After cooling to room temperature, the mixture was filtered, and the obtained solid was recrystallized from ethanol to obtain 15.5 g of an S-form quaternary salt (dibenzoyl tartrate anion).
15 g of the obtained S-form quaternary salt (dibenzoyl tartrate anion), 1.25 g of sodium hydroxide, 19.8 g of water and 19.8 g of toluene were charged and stirred at room temperature for 30 minutes. Oil-water separation was performed, and washing was performed until the aqueous layer became neutral. Then, 2.6 g of hydrochloric acid was added to the oil layer and stirred for 1 hour. When 9.20 g of KPF ₆ was dissolved in 19.8 g of water and 19.8 g of ethyl acetate were added, a solid was precipitated. The precipitated solid was collected by filtration and dried to obtain 8 g (yield 21%) of the S-form quaternary salt (PF ₆ salt) as the target product.

<Step 2> Compound No. 1. Synthesis of (S, S) -isomer of 1. S-isomer quaternary salt (PF ₆ salt) obtained in step 1 3.95 g, diphenylformamidine 1.08 g and pyridine 3.96 g were charged at 50 ° C. Heated for hours. After dropping 6.55 g of acetic anhydride, the mixture was heated at 50 ° C. for 4 hours. Cooled to room temperature and evaporated the solvent. The residue was recrystallized from a mixed solvent of acetone / methanol to obtain the target compound No. 1.4 g (yield 43%) of 1 (S, S) -isomer was obtained. When the CD spectrum of the obtained compound was measured using a circular dichroic dispersometer, positive optical rotation was observed, confirming that it was the target product.

[Production Example 3] Compound No. 1 (R, S) - Body of manufacturing <Step 1> S- body quaternary salt (PF ₆ salt) obtained in Step 1 of Production Example 2 of Intermediate S- body quaternary salt (PF ₆ salt ), 7.85 g of diphenylformamidine and 9.15 g of butanol were charged and heated at 100 ° C. for 9 hours. After cooling to 65 ° C. and adding 36.6 g of methanol, the mixture was kept at 65 ° C. for 30 minutes, and then cooled to room temperature, and the resulting solid was filtered off. After washing with water and methanol, the product was dried to obtain 9.08 g (yield 49%) of the target S-form quaternary salt (PF ₆ salt) intermediate.

<Step 2> Compound No. Synthesis of 1 (R, S) -isomer 1.0 g of S-isomer quaternary salt (PF ₆ salt) intermediate obtained in Step 1 and R-isomer quaternary obtained in Step 1 of Production Example 1 0.79 g of a salt (PF ₆ salt) and 1.58 g of pyridine were charged, and 0.25 g of acetic anhydride was added dropwise, followed by stirring at room temperature for 2 hours and at 50 ° C. for 2 hours. After cooling to room temperature, the solvent was distilled off, and the residue was recrystallized from methanol to obtain the target compound No.1. 350 mg (yield 27%) of 1 (R, S) -isomer was obtained. When the CD spectrum of the obtained compound was measured using a circular dichroic dispersometer, no optical rotation was observed, and it was confirmed that the compound was the target product.

[Production Example 4] Compound No. Preparation of (R, R) -isomer of 2 <Step 1> Synthesis of R-isomer quaternary salt (dibenzoyltartaric acid anion salt) 5.0 g of sodium hydroxide, 95 g of water and 87 g of toluene were charged and stirred with stirring. 37.3 g of -1,2,3-trimethylbenzoindolenine quaternary salt (bromine anion) was gradually added. Oil / water separation was performed, and washing was performed until the aqueous layer became neutral, and then the solvent was distilled off. To the residue, 66 g of ethyl acetate in which 37.6 g of (−)-dibenzoyltartaric acid was dissolved was added dropwise and stirred at 80 ° C. for 1 hour. After cooling to room temperature, filtration was performed, and the obtained solid was recrystallized from ethanol to obtain 11.3 g (yield 17%) of an R-isomer quaternary salt (dibenzoyl tartrate anion).

<Step 2> Compound No. Synthesis of (R, R) -isomer of 2 R-isomer quaternary salt (dibenzoyltartaric acid anion salt) obtained in step 1 was charged with 0.79 g of diphenylformamidine and 6.33 g of pyridine at 60 ° C. After 1.14 g of acetic anhydride was added dropwise, the mixture was heated at 60 ° C. for 30 minutes. After cooling to room temperature, 6.3 g of ethyl acetate, 12.6 g of water and 0.88 g of KPF ₆ were added and stirred for 30 minutes. The precipitated solid was separated by filtration and the target compound No. 1 was obtained. 0.18 g (yield 5.9%) of 2 (R, R) -isomer was obtained. About the obtained compound, when CD spectrum was measured using the circular dichroism dispersometer,-rotation of light was seen and it has confirmed that it was a target object.

[Production Example 5] Compound No. Preparation of (S, S) -isomer of 2 <Step 1> Synthesis of S-isomer quaternary salt (PF ₆ salt) Sodium benzyl 5.0 g, water 45 g and toluene 87 g were charged and stirred with 3-benzyl- 37.3 g of a quaternary salt of 1,2,3-trimethylbenzoindolenine (bromine anion) was gradually added. Oil / water separation was performed, and washing was performed until the aqueous layer became neutral, and then the solvent was distilled off. To the residue was added dropwise 37.6 g of (+)-dibenzoyltartaric acid in 75 g of ethyl acetate, and the mixture was stirred at 80 ° C. for 1 hour. After cooling to room temperature, the mixture was filtered, and the obtained solid was recrystallized from ethanol to obtain 15.5 g of an S-form quaternary salt (dibenzoyl tartrate anion).
15 g of the obtained S-form quaternary salt (dibenzoyl tartrate anion), 1.25 g of sodium hydroxide, 19.8 g of water and 19.8 g of toluene were charged and stirred at room temperature for 30 minutes. Oil-water separation was performed, and washing was performed until the aqueous layer became neutral. Then, 2.6 g of hydrochloric acid was added to the oil layer and stirred for 1 hour. When 9.20 g of KPF ₆ was dissolved in 19.8 g of water and 19.8 g of ethyl acetate were added, a solid was precipitated. The precipitated solid was separated by filtration and dried to obtain 3.8 g (yield 8.5%) of the target S-form quaternary salt (PF ₆ salt).

<Step 2> Compound No. Synthesis of (S, S) -isomer of 2 S-isomer quaternary salt (PF ₆ salt) obtained in Step 1, 3.12 g, diphenylformamidine 2.06 g and pyridine 0.55 g were charged at 60 ° C. Heated for hours. After dropwise addition of 5.1 g of acetic anhydride, the mixture was heated at 60 ° C. for 10 minutes. Cooled to room temperature and evaporated the solvent. The residue was recrystallized from a mixed solvent of acetone / methanol to obtain the target compound No. 0.14 g (yield 4.6%) of 2 (S, S) -isomer was obtained. When the CD spectrum of the obtained compound was measured using a circular dichroic dispersometer, positive optical rotation was observed, confirming that it was the target product.

[Production Example 6] Compound No. 2. Production of (R, S) -isomer of 3.12 g of R-isomer quaternary salt (PF ₆ salt) obtained in Step 1 of Production Example 4, 2.06 g of diphenylformamidine, 0.55 g of pyridine and butanol 5.28 g was charged and heated at 70 ° C. for 7 hours. After cooling to room temperature, the solvent was distilled off, 10.9 g of pyridine and 5.1 g of acetic anhydride were added, and the mixture was stirred for 10 minutes. After adding 3.12 g of the S-form quaternary salt (PF ₆ salt) obtained in Step 1 of Production Example 5 and heating at 60 ° C. for 2 hours, adding 15 g of methanol and holding at 65 ° C. for 30 minutes, The solid obtained after cooling to room temperature was filtered off. After washing with methanol and drying, the target compound No. 2.3 g (yield 44%) of 2 (R, S) -isomer was obtained. When the CD spectrum of the obtained compound was measured using a circular dichroic dispersometer, no optical rotation was observed, and it was confirmed that the compound was the target product.

[Examples 1 to 4]
Compound No. 1 (R, S) -form and (R, R) (S, S) -form, as well as compound no. 2, (R, S) -form and (R, R) (S, S) -form are each converted into 2,2,3,3-tetrafluoropropanol so that the cyanine compound concentration is 1.0% by mass. To obtain an optical recording material as a 2,2,3,3-tetrafluoropropanol solution. A titanium chelate compound (T-50: manufactured by Nippon Soda Co., Ltd.) is applied, hydrolyzed, and the above optical recording material is spin-coated on a polycarbonate disk substrate having a diameter of 12 cm provided with a base layer (0.01 μm). The optical recording layer was coated to form an optical recording layer having a thickness of 100 nm. 1-No. 4 were obtained respectively.

[Comparative Example 1]
In place of the cyanine compound according to the present invention, the following comparative compound No. A comparative optical recording material was produced in the same manner as in Examples 1 to 4 except that Comparative Optical Recording Medium No. 1 was used. 1 was obtained.

[Evaluation Examples 1-1 to 1-4 and Comparative Evaluation Examples 1-1 to 1-3]
Compound No. 1 (R, S) -form and (R, R) (S, S) -form, Compound No. 2 (R, S) -form and (R, R) (S, S) -form and Comparative Compound No. 1 of Comparative Example 1. 1, compound no. The total mixture of isomers of 1 and compound no. The total mixture of the two isomers was evaluated for thermal decomposition behavior. The evaluation was carried out by differential thermal analysis measurement at a heating rate of 10 ° C./min in a nitrogen stream and in air, and the thermal decomposition temperature was compared and evaluated with the peak top temperature of DTA exotherm. The evaluation results are shown in the following [Table 1].

  As is apparent from [Table 1], it was confirmed that the cyanine compound according to the present invention is suitable for high-speed recording because it generates a small amount of heat and suppresses thermal interference. On the other hand, Comparative Compound No. No. 1 had a high decomposition point and a large calorific value, and the total mixture of isomers also had a large calorific value compared to the isomers of the corresponding compounds, and did not show good thermal decomposition behavior.

[Evaluation Examples 2-1 to 2-4 and Comparative Evaluation Example 2-1]
Compound No. 1 (R, S) -form and (R, R) (S, S) -form, Compound No. 2 (R, S) -form and (R, R) (S, S) -form and Comparative Compound No. 1 of Comparative Example 1. 1 was evaluated for solubility in 2,2,3,3-tetrafluoropropanol at 30 ° C. Evaluation was performed by adding a cyanine compound to 2,2,3,3-tetrafluoropropanol in 0.5 mass% increments in the range of 0.5 mass% to 10.0 mass%, and observing dissolution and insolubility. . The results are shown in [Table 2].

  As is apparent from [Table 2], the optical recording medium having the optical recording layer formed of the optical recording material of the present invention has high solubility, and thus has high film stability and is suitably used as an optical recording medium. I was able to confirm that it was possible.

Claims (5)

(B) A cyanine compound represented by the following general formula (I), which is an isomer other than at least one of optical isomers having an asymmetric atom represented by * in the general formula (I) as a chiral center An optical recording material comprising a simple substance or a mixture thereof and (b) a solvent.

(In the formula, ring A and ring B each independently represent an optionally substituted benzene ring or naphthalene ring, and R ¹ is represented by the following general formula (II) or (II ′)). R ² represents a group represented by the following general formulas (II), (II ′) and (III) or an organic group having 1 to 30 carbon atoms, provided that R ¹ and R ² are the same. R ³ and R ⁴ are each independently a group represented by the following general formulas (II), (II ′), (III), an organic group having 1 to 30 carbon atoms, or a linkage. And Y ¹ and Y ² each independently represents an organic group having 1 to 30 carbon atoms or a group represented by the following general formula (III), L Represents a polymethine chain which may contain a ring structure in the chain, and the hydrogen atom in the polymethine chain is a halogen atom, a cyano group, a hydroxyl group, an alkyl group, an alkoxy group or an aryl group. The alkyl group, the alkoxy group, and the aryl group may be further substituted, An ^m- represents an m-valent anion, m is 1 or 2, and p is , Represents the coefficient to keep the charge neutral.)

(In the above general formula (II), the bond between G and T is a double bond, a conjugated double bond or a triple bond, G represents a carbon atom, and T represents a carbon atom, an oxygen atom or a nitrogen atom. , W represents a number from 0 to 4, x, y and z represent 0 or 1 (provided that when T is an oxygen atom, y and z are 0, and when T is a nitrogen atom, y + z) Is 0 or 1.), R ⁰¹ , R ⁰² , R ⁰³ and R ⁰⁴ are each independently a hydrogen atom, a hydroxyl group, a cyano group, a nitro group, a halogen atom or a carbon which may have a substituent. Represents an alkyl group having 1 to 4 atoms, and the methylene group in the alkyl group may be substituted with —O— or —CO—, and R ⁰¹ and R ⁰⁴ may be bonded to form a cycloalkene ring or a heterocycle; In the above general formula (II ′), the bond between G ′ and T ′ is a double bond or a conjugated double bond. A case, G 'represents a carbon atom, T' represents a carbon atom or a nitrogen atom, w 'represents a number from 0 to 4, R ^01' represents a hydrogen atom, a hydroxyl group, a cyano group, a nitro group, Represents a halogen atom or an optionally substituted alkyl group having 1 to 4 carbon atoms, and the methylene group in the alkyl group may be substituted with —O— or —CO—, and G ′ And a ring containing T ′ represents a 5-membered ring which may contain a heteroatom, a 6-membered ring which may contain a heteroatom, a naphthalene ring, a quinoline ring, an isoquinoline ring, an anthracene ring or an anthraquinone ring. The ring containing 'may be substituted with a halogen atom, a nitro group, a cyano group, an alkyl group or an alkoxy group.)

(Wherein R ^{a to} R ⁱ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and the methylene group in the alkyl group is substituted with —O— or —CO—). Q represents an alkylene group having 1 to 8 carbon atoms which may have a direct bond or a substituent, and the methylene group in the alkylene group is -O-, -S-, -CO-. , —COO—, —OCO—, —SO ₂ —, —NH—, —CONH—, —NHCO—, —N═CH— or —CH═CH—, where M is Fe, (Co, Ni, Ti, Cu, Zn, Zr, Cr, Mo, Os, Mn, Ru, Sn, Pd, Rh, Pt, or Ir are represented.) 2. The optical recording material according to claim 1, wherein the cyanine compound represented by the general formula (I) is a compound represented by the following general formula (IV).

(In the formula, ring A, R ¹ , R ² , Y ¹ , L, An ^m− , m and p are the same as those in the general formula (I).) The optical recording material according to claim 2, wherein the cyanine compound represented by the general formula (IV) is a compound represented by the following general formula (V).

(In the formula, ring A, Y ¹ , An ^m− , m and p are the same as those in the general formula (I), R ⁵¹ is a group represented by the following general formula (VI), and R ⁵² is It is a group represented by the above general formulas (II), (II ′) and (III) different from R ⁵¹ or an organic group having 1 to 30 carbon atoms.

(In the formula, R ⁰¹ , R ⁰² , R ⁰³ and R ⁰⁴ are the same as those in the general formula (II).) The optical recording material according to claim 2, wherein the cyanine compound represented by the general formula (IV) is a compound represented by the following general formula (VII).

(In the formula, rings A, Y ¹ , An ^m− , m and p are the same as those in the general formula (I), R ⁷¹ is a group represented by the following general formula (VIII), and R ⁷² is It is a group represented by the above general formulas (II), (II ′) and (III) different from R ⁷¹ or an organic group having 1 to 30 carbon atoms.

(In the formula, rings A, R ² , Y ¹ , An ^m- and p are the same as those in the general formula (I), Z represents an alkyl group having 1 to 4 carbon atoms, and n is 0. A number of ~ 5.)   An optical recording medium comprising an optical recording layer formed from the optical recording material according to claim 1 on a substrate.