JP2009248307A - Optical information recording medium, information recording method and azo metal complex coloring matter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical information recording medium showing excellent record reproducibility and light resistance in information recording by a short wavelength laser rays irradiation, and excellent shelf stability in a solution, as well as a new chemical compound which is best-suited as a coloring matter for recording layer of the optical information recording medium. <P>SOLUTION: This optical information recording medium has a recording layer formed on the surface of a substrate having a pregroove with a track pitch of 50 to 500 nm on the surface. The recording layer contains an azo metal complex coloring matter which is a complex of an azo coloring matter and a metallic ion which is represented by formula (1). In this formula (1), Q<SP>1</SP>is an atomic group which forms a nitrogen-containing heterocycle together with a carbon atom and a nitrogen atom which are adjacent to each other, G<SP>1</SP>is a heterocycle and a carbon ring and E<SP>1</SP>is an electron-withdrawing group. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an optical information recording medium capable of recording and reproducing information using a laser beam, and more specifically, a heat mode type light suitable for recording and reproducing information using a short wavelength laser beam having a wavelength of 440 nm or less. The present invention relates to an information recording medium and an information recording method for recording information on the optical information recording medium by irradiation with a short wavelength laser beam having a wavelength of 440 nm or less.
The present invention further relates to a novel azo metal complex dye suitable as a dye for a recording layer of an optical information recording medium.

  Recently, networks such as the Internet and high-definition TVs are rapidly spreading, and the demand for large-capacity recording media for recording image information inexpensively and easily is increasing due to the close-up of HDTV (High Definition Television). ing. However, it cannot be said that the CD-R and DVD-R have a recording capacity that is large enough to meet future requirements. Therefore, in order to improve the recording density by using a laser beam having a wavelength shorter than that of the DVD-R, development of a large-capacity optical disc capable of recording with a short wavelength laser (for example, a wavelength of 440 nm or less) has been advanced. As such optical discs, optical information recording media having a high recording density such as Blu-ray Disc (hereinafter also referred to as “BD”) and HD-DVD have been proposed.

In optical recording disks using short-wavelength laser light (for example, 405 nm blue laser light), it has been studied to shorten the absorption wavelength of the azo metal complex used in DVD-R (patent). Literature 1-4). On the other hand, Patent Document 5 discloses an azo metal complex dye applicable to both an optical information disk using a short wavelength laser beam and a DVD-R.
JP 2001-158862 A JP 2006-142789 A JP 2006-306070 A JP 2007-26541 A JP 2004-291244 A

However, the present inventors have evaluated the light resistance of the dye film and the recording / reproduction characteristics of an optical information recording medium for a short wavelength laser such as a blue laser for the azo metal complexes described in Patent Documents 1 to 5 above. None of them were able to satisfy all of light resistance and recording / reproduction characteristics.
In addition, in order to produce an optical information recording medium in a large amount at a low cost, it is desired that the dye solution for forming the recording layer is easily stored stably for a long period of time. It was also found that the storage stability (solution stability) in the solution of the azo metal complex is insufficient.

  Therefore, an object of the present invention is to provide an optical information recording medium excellent in recording / reproduction characteristics and light resistance in information recording by short-wavelength laser light irradiation (particularly information recording by laser light irradiation having a wavelength of 440 nm or less), and in a solution. An object of the present invention is to provide a novel compound which is excellent in storage stability and suitable as a dye for a recording layer of an optical information recording medium.

  In order to achieve the above object, the present inventors have conducted extensive studies based on the idea that the structure of the ligand is a factor regarding the recording / reproduction characteristics, light resistance, and solution stability. The azo metal complex dye containing the azo ligand represented by the formula (1) was found to exhibit extremely good light resistance and solution stability, and excellent recording characteristics with a short wavelength laser beam, thereby completing the present invention. It was.

［一般式（１）中、Ｑ¹は隣り合う炭素原子および窒素原子とともに含窒素複素環を形成する原子群を表し、Ｇ¹は複素環または炭素環を表し、Ｅ¹は電子求引性基を表す。］
[２]一般式（１）中、Ｇ¹は、下記部分構造を表す[１]に記載の光情報記録媒体。

[上記において、＊は−Ｎ＝Ｎ−基との結合位置を表し、Ｑ²は隣り合う炭素原子および窒素原子とともに含窒素複素環を形成する原子群を表す。]
[３]一般式（１）中、Ｇ¹は、ピラゾール環、チアジアゾール環またはイソオキサゾール環を表す[１]または[２]に記載の光情報記録媒体。
[４]一般式（１）中、Ｑ¹と隣り合う炭素原子および窒素原子により形成される含窒素複素環は、ピリジン環、チアゾール環、オキサゾール環、イミダゾール環、下記部分構造（Ｃ−１）または（Ｃ−２）のいずれかを表す[１]〜[３]のいずれかに記載の光情報記録媒体。

[上記において、Ｒ¹〜Ｒ⁶は、各々独立に水素原子または置換基を表し、＊は炭素原子との結合位置を表す。]
[５]前記アゾ金属錯体色素は、下記一般式（３）で表されるアゾ色素と、銅イオン、ニッケルイオン、コバルトイオンまたは鉄イオンとの錯体であるアゾ金属錯体色素である[１]に記載の光情報記録媒体。

[一般式（３）中、Ｅ²はシアノ基またはアルコキシカルボニル基を表し、Ｑ³は隣り合う炭素原子および窒素原子とともにピリジン環、オキサゾール環、チアゾール環、下記部分構造（Ｃ−１）または（Ｃ−２）のいずれかを形成する原子群を表し、Ｑ⁴は隣り合う炭素原子および窒素原子とともに含窒素複素環を形成する原子群を表す。］

[上記において、Ｒ¹〜Ｒ⁶は、各々独立に水素原子または置換基を表し、＊は炭素原子との結合位置を表す。]
[６]一般式（３）中のＱ⁴と隣り合う炭素原子および窒素原子とともに形成される環構造は、下記部分構造で表される[５]に記載の光情報記録媒体。

[上記において、＊は−Ｎ＝Ｎ−基との結合位置を表し、Ｒ⁷〜Ｒ⁹は各々独立に水素原子または置換基を表す。]
[７]前記アゾ金属錯体色素は、一般式（１）で表されるアゾ色素と、該アゾ色素の数と同数またはそれ以上の数の遷移金属イオンとの錯体であるアゾ金属錯体色素を含み、該アゾ金属錯体色素は１分子中に２つ以上の遷移金属イオンを含有し、但し、上記アゾ金属錯体色素１分子中に含まれる複数の遷移金属イオンはそれぞれ同一でも異なっていてもよく、上記アゾ金属錯体色素１分子中に複数のアゾ色素が含まれる場合、複数のアゾ色素はそれぞれ同一でも異なっていてもよい、[１]〜[６]のいずれかに記載の光情報記録媒体。
[８]波長４４０ｎｍ以下のレーザ光を照射することにより情報を記録するために使用される[１]〜[７]のいずれかに記載の光情報記録媒体。
[９]基板と記録層との間に反射層を有し、前記レーザ光を上記反射層と対向する面とは反対の面側から記録層へ照射する[８]に記載の光情報記録媒体。
[１０][１]〜[９]のいずれかに記載の光情報記録媒体に、波長４４０ｎｍ以下のレーザ光を照射することにより、上記光情報記録媒体が有する記録層へ情報を記録する情報記録方法。
[１１]下記一般式（５）で表されるアゾ色素と、該アゾ色素の数と同数またはそれ以上の数の銅イオンとの錯体であり、かつ１分子中に２つ以上の銅イオンを含有するアゾ金属錯体色素。

[一般式（５）中、Ｅ²はシアノ基またはアルコキシカルボニル基を表し、Ｑ³は隣り合う炭素原子および窒素原子とともにピリジン環、オキサゾール環、チアゾール環、下記部分構造（Ｃ−１）または（Ｃ−２）のいずれかを形成する原子群を表し、Ｒ⁷およびＲ⁸は各々独立に水素原子または置換基を表す。］

[上記において、Ｒ¹〜Ｒ⁶は、各々独立に水素原子または置換基を表し、＊は炭素原子との結合位置を表す。] That is, the above object was achieved by the following means.
[1] An optical information recording medium having a recording layer on the surface of a substrate having a pregroove with a track pitch of 50 to 500 nm on the surface,
The recording layer contains an azo metal complex dye, which is a complex of an azo dye and a metal ion represented by the following general formula (1).

[In General Formula (1), Q ¹ represents an atomic group that forms a nitrogen-containing heterocyclic ring together with adjacent carbon atoms and nitrogen atoms, G ¹ represents a heterocyclic ring or a carbocyclic ring, and E ¹ represents an electron withdrawing group. Represents. ]
[2] The optical information recording medium according to [1], wherein G ¹ in the general formula (1) represents the following partial structure.

[In the above, * represents the bonding position to the —N═N— group, and Q ² represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. ]
[3] The optical information recording medium according to [1] or [2], wherein G ¹ in general formula (1) represents a pyrazole ring, a thiadiazole ring, or an isoxazole ring.
[4] In the general formula (1), the nitrogen-containing heterocycle formed by the carbon atom and the nitrogen atom adjacent to Q ¹ is a pyridine ring, a thiazole ring, an oxazole ring, an imidazole ring, the following partial structure (C-1) Or the optical information recording medium in any one of [1]-[3] showing either of (C-2).

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ]
[5] The azo metal complex dye is an azo metal complex dye that is a complex of an azo dye represented by the following general formula (3) and a copper ion, nickel ion, cobalt ion, or iron ion: The optical information recording medium described.

[In General Formula (3), E ² represents a cyano group or an alkoxycarbonyl group, and Q ³ together with the adjacent carbon atom and nitrogen atom, a pyridine ring, an oxazole ring, a thiazole ring, the following partial structure (C-1) or ( C-2) represents an atomic group that forms any one of the above, and Q ⁴ represents an atomic group that forms a nitrogen-containing heterocyclic ring together with adjacent carbon atoms and nitrogen atoms. ]

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ]
[6] The optical information recording medium according to [5], wherein the ring structure formed together with the carbon atom and nitrogen atom adjacent to Q ⁴ in the general formula (3) is represented by the following partial structure.

[In the above, * represents a bonding position with —N═N— group, and R ^{7 to} R ⁹ each independently represents a hydrogen atom or a substituent. ]
[7] The azo metal complex dye includes an azo metal complex dye which is a complex of the azo dye represented by the general formula (1) and a transition metal ion having the same number or more than the number of the azo dye. The azo metal complex dye contains two or more transition metal ions in one molecule, provided that the plurality of transition metal ions contained in one molecule of the azo metal complex dye may be the same or different from each other, The optical information recording medium according to any one of [1] to [6], wherein when a plurality of azo dyes are contained in one molecule of the azo metal complex dye, the plurality of azo dyes may be the same or different from each other.
[8] The optical information recording medium according to any one of [1] to [7], which is used for recording information by irradiating a laser beam having a wavelength of 440 nm or less.
[9] The optical information recording medium according to [8], having a reflective layer between the substrate and the recording layer, and irradiating the recording layer with the laser beam from a surface opposite to the surface facing the reflective layer. .
[10] Information recording for recording information on a recording layer of the optical information recording medium by irradiating the optical information recording medium according to any one of [1] to [9] with a laser beam having a wavelength of 440 nm or less. Method.
[11] A complex of an azo dye represented by the following general formula (5) and a copper ion having the same number or more than the number of the azo dye, and two or more copper ions in one molecule Contains azo metal complex dye.

[In General Formula (5), E ² represents a cyano group or an alkoxycarbonyl group, Q ³ together with the adjacent carbon atom and nitrogen atom, a pyridine ring, an oxazole ring, a thiazole ring, the following partial structure (C-1) or ( represents an atomic group forming one of the C-2), R ⁷ and R ⁸ each independently represent a hydrogen atom or a substituent. ]

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ]

  The azo metal complex dye of the present invention can exhibit excellent light resistance and good solution stability. Furthermore, according to the present invention, an optical information recording medium (especially laser light irradiation with a wavelength of 440 nm or less) having excellent recording / reproduction characteristics using a blue laser beam with a wavelength of 440 nm or less and excellent light resistance. Can be obtained.

  Hereinafter, the optical information recording medium, the information recording method, and the azo metal complex dye of the present invention will be described in detail.

[Optical information recording medium]
The optical information recording medium of the present invention is an optical information recording medium having a recording layer on the surface of a substrate having a pregroove with a track pitch of 50 to 500 nm on the surface, and recording and reproducing information with a short wavelength laser. It is suitable as an optical disc for high-density recording such as HD-DVD.
The high-density recording optical disk has a structural feature that the track pitch is narrower than that of a conventional write-once optical disk. In addition, a BD-structured optical disc has a recording layer on a substrate directly or via a layer such as a reflective layer, and a relatively thin light-transmitting layer on the recording layer (generally called a cover layer). The layer structure is different from that of a conventional write-once optical disc. In such an optical information recording medium having a structure different from that of a conventional write-once optical disc, a recording dye used in a conventional write-once optical disc such as a CD-R or DVD-R can obtain sufficient recording characteristics. It was difficult. On the other hand, the optical information recording medium of the present invention has good recording / reproduction characteristics by including at least one azo metal complex dye, which is a complex of the azo dye represented by the general formula (1) and a metal ion, in the recording layer. Made it possible to get. According to the optical information recording medium of the present invention, good recording characteristics can be obtained by irradiation with laser light having a short wavelength (for example, a wavelength of 440 nm or less). In particular, the optical information recording medium of the present invention is suitable as a BD medium having a structure having a reflective layer between a substrate and a recording layer. Furthermore, it was newly found that the azo metal complex dye exhibits extremely good light resistance and good solution stability. The optical information recording medium of the present invention can satisfy both the recording characteristics by irradiation with a short wavelength laser beam and high light resistance by including the azo metal complex dye in the recording layer. Furthermore, since the optical information recording medium of the present invention can be formed using a recording layer dye having high storage stability in a solution, high productivity can also be realized.
Below, the detail of the azo metal complex dye in this invention is demonstrated.

  In the present invention, only the azoform in the azo-hydrazone tautomeric equilibrium is described as the azo dye, but it may be a corresponding hydrazone form, and the hydrazone form in that case is the same component as the azoform in the present invention. And

The optical information recording medium of the present invention contains an azo metal complex dye which is a complex of an azo dye represented by the following general formula (1) and a metal ion.

  The azo metal complex dye may be a complex containing the azo dye represented by the general formula (1) and a metal ion as constituents, and neutralizes the charge of the ligand and the molecule together with the azo dye and the metal ion. Therefore, other components such as ions necessary for the purpose may be included.

  Examples of metal ions include Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Sr, Y, Zr, Nb, and Mo. , Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Ba, Pr, Eu, Yb, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi And metal ions such as Th. The metal ion may be a metal oxide ion, and examples of the metal oxide ion include oxides of these metals.

  Among the above, ions of transition metal atoms are preferable. A transition metal atom is an element having an incomplete d-electron shell, including elements of Group IIIa to Group VIII and Group Ib of the periodic table. Although it does not specifically limit as a transition metal atom, Mn, Fe, Co, Ni, Cu, and Zn are preferable, Co, Ni, Cu, and Fe are more preferable, Cu is still more preferable.

As the metal ion, a divalent or trivalent metal ion is preferable. Examples of the divalent or trivalent metal ions include Mn ²⁺ , Fe ²⁺ , Fe ³⁺ , Co ²⁺ , Co ³⁺ , Ni ²⁺ , Ni ³⁺ , Cu ²⁺ , Zn ²⁺ and Cr. ³⁺ , Ru ²⁺ , Rh ³⁺ , Pd ²⁺ , Ir ³⁺ , Pt ^{2+ and the} like, such as Mn ²⁺ , Fe ²⁺ , Fe ³⁺ , Co ²⁺ , Co ³⁺ , Ni ^2+. , Ni ³⁺ , Cu ²⁺ and Zn ²⁺ are preferred, Co ²⁺ , Co ³⁺ , Ni ²⁺ , Ni ³⁺ , Cu ²⁺ , Fe ²⁺ and Fe ³⁺ are more preferred, and Cu ²⁺ is preferred. Further preferred.

In the general formula ^(1), E 1 represents an electron-withdrawing group. In the present invention, the “electron withdrawing group” means a group having Hammett's substituent constant σp value of 0.20 or more. Here, Hammett's substituent constant σp value used in the present invention will be described.
Hammett's rule was found in 1935 by L. L. in order to quantitatively discuss the effect of substituents on the reaction or equilibrium of benzene derivatives. P. A rule of thumb proposed by Hammett, which is widely accepted today. Substituent constants determined by Hammett's rule include a σp value and a σm value, and these values can be found in many general books. A. Dean, “Lange's Handbook of Chemistry”, 12th edition, 1979 (Mc Graw-Hill) and “Chemicals” special edition, 122, 96-103, 1979 (Nankodo). In the present invention, each substituent is defined or explained by Hammett's substituent constant σp, but this is limited to only a substituent having a known value that can be found in the above-mentioned book. Needless to say, it also includes substituents that would be included in the range when measured based on Hammett's rule even if the value is unknown. Azo dye represented by a general formula (1) is, .sigma.p value as E ¹ is by having less than 0.20 electron-groups, it is possible to obtain an azo metal complex that exhibits the desired properties described above .

Specific examples of the electron withdrawing group E ^{1 having} a σp value of 0.20 or more include an acyl group, an acyloxy group, a carbamoyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, a cyano group, a nitro group, and a dialkylphosphono group. Diarylphosphono group, diarylphosphinyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfonyloxy group, acylthio group, sulfamoyl group, thiocyanate group, thiocarbonyl group, halogenated alkyl group, A halogenated alkoxy group, a halogenated aryloxy group, a halogenated alkylamino group, a halogenated alkylthio group, an aryl group substituted with another electron withdrawing group having a σp value of 0.20 or more, a heterocyclic group, a halogen atom , Diazenyl group and selenasia Include the over door group.

Each of the above groups may further have a substituent, and the substituent in that case is not particularly limited. For example, a halogen atom, an alkyl group (including a cycloalkyl group and a bicycloalkyl group), an alkenyl group ( (Including cycloalkenyl groups and bicycloalkenyl groups), alkynyl groups, aryl groups, heterocyclic groups, cyano groups, hydroxyl groups, nitro groups, carboxyl groups, alkoxy groups, aryloxy groups, silyloxy groups, heterocyclic oxy groups, acyloxy groups Carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (including anilino group), acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, Alkyl and a Arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, Examples include carbamoyl groups, aryl and heterocyclic azenyl groups, imide groups, phosphino groups, phosphinyl groups, phosphinyloxy groups, phosphinylamino groups, and silyl groups.
More specifically, a halogen atom (for example, a chlorine atom, a bromine atom, an iodine atom), an alkyl group [a linear, branched, or cyclic substituted or unsubstituted alkyl group is represented. They are alkyl groups (preferably alkyl groups having 1 to 30 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, t-butyl group, n-octyl group, eicosyl group, 2-chloroethyl group, 2-cyanoethyl group, 2-ethylhexyl group), cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, such as cyclohexyl group, cyclopentyl group, 4-n-dodecylcyclohexyl group), Bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, that is, a monovalent group obtained by removing one hydrogen atom from a bicycloalkane having 5 to 30 carbon atoms. For example, bicyclo [1,2,2] heptan-2-yl, bicyclo [2,2,2] octane-3-yl), and ring structure Often tricyclo structure and the like are also intended to cover. An alkyl group (for example, an alkyl group of an alkylthio group) in the substituents described below also represents such an alkyl group. ], An alkenyl group [represents a linear, branched or cyclic substituted or unsubstituted alkenyl group. They are an alkenyl group (preferably a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, such as a vinyl group, an allyl group, a prenyl group, a geranyl group, an oleyl group), a cycloalkenyl group (preferably a carbon number of 3 A substituted or unsubstituted cycloalkenyl group having ˜30, that is, a monovalent group obtained by removing one hydrogen atom of a cycloalkene having 3 to 30 carbon atoms, such as 2-cyclopenten-1-yl and 2-cyclohexene. -1-yl), a bicycloalkenyl group (substituted or unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, that is, a hydrogen atom of a bicycloalkene having one double bond A monovalent group, for example, bicyclo [2,2,1] hept-2-en-1-yl, bicycl [2,2,2] oct-2-en-4-yl). An alkynyl group (preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, such as an ethynyl group, a propargyl group, a trimethylsilylethynyl group, an aryl group (preferably a substituted or unsubstituted group having 6 to 30 carbon atoms). Aryl groups such as phenyl, p-tolyl, naphthyl, m-chlorophenyl, o-hexadecanoylaminophenyl), heterocyclic groups (preferably 5- or 6-membered substituted or unsubstituted aromatic or non-aromatic heterocycles A monovalent group obtained by removing one hydrogen atom from a compound, more preferably a 5- or 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms, such as a 2-furyl group, 2- Thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group), cyano group, hydroxyl group, nitro group, carboxyl group, alcohol Si group (preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, such as a methoxy group, an ethoxy group, an isopropoxy group, a t-butoxy group, an n-octyloxy group, a 2-methoxyethoxy group), An aryloxy group (preferably a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms such as phenoxy group, 2-methylphenoxy group, 4-t-butylphenoxy group, 3-nitrophenoxy group, 2-tetra Decanoylaminophenoxy group), silyloxy group (preferably silyloxy group having 3 to 20 carbon atoms, for example, trimethylsilyloxy group, t-butyldimethylsilyloxy group), heterocyclic oxy group (preferably having 2 to 30 carbon atoms) Substituted or unsubstituted heterocyclic oxy group, 1-phenyltetrazole-5-oxy group, 2- A trahydropyranyloxy group), an acyloxy group (preferably a formyloxy group, a substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms, for example, , Formyloxy group, acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group), carbamoyloxy group (preferably a substituted or unsubstituted carbamoyloxy group having 1 to 30 carbon atoms) , For example, N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N, N-di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy group), Alkoxycarbonyl An oxy group (preferably a substituted or unsubstituted alkoxycarbonyloxy group having 2 to 30 carbon atoms, such as a methoxycarbonyloxy group, an ethoxycarbonyloxy group, a t-butoxycarbonyloxy group, an n-octylcarbonyloxy group), an aryloxycarbonyl Oxy group (preferably a substituted or unsubstituted aryloxycarbonyloxy group having 7 to 30 carbon atoms, such as phenoxycarbonyloxy group, p-methoxyphenoxycarbonyloxy group, pn-hexadecyloxyphenoxycarbonyloxy group) An amino group (preferably an amino group, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, a substituted or unsubstituted anilino group having 6 to 30 carbon atoms, such as an amino group, a methylamino group, dimethylamino; Group, anilino group, -Methyl-anilino group, diphenylamino group), acylamino group (preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms, substituted or unsubstituted arylcarbonyl group having 6 to 30 carbon atoms) An amino group such as formylamino group, acetylamino group, pivaloylamino group, lauroylamino group, benzoylamino group, 3,4,5-tri-n-octyloxyphenylcarbonylamino group), aminocarbonylamino group (preferably, C1-C30 substituted or unsubstituted aminocarbonylamino group, for example, carbamoylamino group, N, N-dimethylaminocarbonylamino group, N, N-diethylaminocarbonylamino group, morpholinocarbonylamino group), alkoxycarbonylamino Group ( Preferably, it is a substituted or unsubstituted alkoxycarbonylamino group having 2 to 30 carbon atoms, such as methoxycarbonylamino group, ethoxycarbonylamino group, t-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxy. Carbonylamino group), aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms, such as phenoxycarbonylamino group, p-chlorophenoxycarbonylamino group, mn- Octyloxyphenoxycarbonylamino group), sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, such as sulfamoylamino group, N, N-dimethylaminosulfonylamino group) Group, Nn-octylaminosulfonylamino group), alkyl and arylsulfonylamino group (preferably substituted or unsubstituted alkylsulfonylamino group having 1 to 30 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms) Sulfonylamino groups such as methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,5-trichlorophenylsulfonylamino group, p-methylphenylsulfonylamino group), mercapto group, alkylthio group (preferably A substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, such as a methylthio group, an ethylthio group or an n-hexadecylthio group, an arylthio group (preferably a substituted or unsubstituted arylthio group having 6 to 30 carbon atoms, such as a phenylthio group) , P-ku Rophenylthio group, m-methoxyphenylthio group), heterocyclic thio group (preferably a substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms, such as 2-benzothiazolylthio group, 1-phenyltetrazole-5 -Ylthio group), sulfamoyl group (preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, such as N-ethylsulfamoyl group, N- (3-dodecyloxypropyl) sulfamoyl group, N, N- Dimethylsulfamoyl group, N-acetylsulfamoyl group, N-benzoylsulfamoyl group, N- (N′-phenylcarbamoyl) sulfamoyl group), sulfo group, alkyl and arylsulfinyl group (preferably having 1 carbon atom) A substituted or unsubstituted alkylsulfinyl group of ˜30, a substituted or Unsubstituted arylsulfinyl group, for example, methylsulfinyl group, ethylsulfinyl group, phenylsulfinyl group, p-methylphenylsulfinyl group), alkyl and arylsulfonyl group (preferably substituted or unsubstituted alkyl having 1 to 30 carbon atoms) A sulfonyl group, a substituted or unsubstituted arylsulfonyl group having 6 to 30 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a phenylsulfonyl group, a p-methylphenylsulfonyl group, an acyl group (preferably a formyl group, a carbon number) Hetero bonded to a carbonyl group by a substituted or unsubstituted alkylcarbonyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted carbon atom having 4 to 30 carbon atoms A ring carbonyl group, for example, acetyl , Pivaloyl group, 2-chloroacetyl group, stearoyl group, benzoyl group, pn-octyloxyphenylcarbonyl group, 2-pyridylcarbonyl group, 2-furylcarbonyl group), aryloxycarbonyl group (preferably having 7 carbon atoms) To 30 substituted or unsubstituted aryloxycarbonyl groups such as phenoxycarbonyl group, o-chlorophenoxycarbonyl group, m-nitrophenoxycarbonyl group, pt-butylphenoxycarbonyl group), alkoxycarbonyl group (preferably, A substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, or an n-octadecyloxycarbonyl group), a carbamoyl group (preferably having 1 to 30 carbon atoms) Replace Or unsubstituted carbamoyl groups such as carbamoyl group, N-methylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-di-n-octylcarbamoyl group, N- (methylsulfonyl) carbamoyl group), aryl and A heterocyclic azo group (preferably a substituted or unsubstituted arylazo group having 6 to 30 carbon atoms, a substituted or unsubstituted heterocyclic azeenyl group having 3 to 30 carbon atoms, such as a phenylazo group, a p-chlorophenylazo group, 5- Ethylthio-1,3,4-thiadiazol-2-ylazo group), imide group (preferably N-succinimide group, N-phthalimide group), phosphino group (preferably substituted or unsubstituted having 2 to 30 carbon atoms) Phosphino groups such as dimethylphosphino group, diphenylphosphino group, methylphenoxy group Phosphino group), phosphinyl group (preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms, such as phosphinyl group, dioctyloxyphosphinyl group, diethoxyphosphinyl group), phosphinyloxy group ( Preferably, it is a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, such as diphenoxyphosphinyloxy, dioctyloxyphosphinyloxy), a phosphinylamino group (preferably having 2 to 2 carbon atoms). 30 substituted or unsubstituted phosphinylamino groups such as dimethoxyphosphinylamino group and dimethylaminophosphinylamino group, silyl groups (preferably substituted or unsubstituted silyl groups having 3 to 30 carbon atoms) For example, trimethylsilyl group, t-butyldimethylsilyl group, phenyldimethylsilyl Group), and the like. Among these functional groups, those having a hydrogen atom may be substituted with the above groups by removing this.

Preferred examples of the electron withdrawing group represented by E ¹ include acyl groups having 2 to 12 carbon atoms, alkoxycarbonyl groups having 2 to 12 carbon atoms, carbamoyl groups having 1 to 12 carbon atoms, and 7 to 18 carbon atoms. Aryloxycarbonyl group, cyano group, nitro group, C1-C12 alkylsulfinyl group, C6-C18 arylsulfinyl group, C1-C12 alkylsulfonyl group, C6-C18 An arylsulfonyl group, a sulfamoyl group having 0 to 12 carbon atoms, an aryl group having 7 to 18 carbon atoms substituted with two or more other electron-withdrawing groups having a σp value of 0.20 or more, and 1 to carbon atoms And a heterocyclic group having 18 nitrogen atoms, oxygen atoms or sulfur atoms.

E ¹ is more preferably an alkyloxycarbonyl group having 2 to 12 carbon atoms, a nitro group, a cyano group, an alkylsulfonyl group having 1 to 12 carbon atoms, an arylsulfonyl group having 6 to 18 carbon atoms, or an alkylsulfonyl group having 1 to 12 carbon atoms. More preferably an alkyloxycarbonyl group having 2 to 12 carbon atoms or a cyano group, and a cyano group is particularly preferred.

In the general formula (1), Q ¹ represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. The nitrogen-containing heterocyclic ring formed by Q ¹ is not particularly limited, but is preferably a 5-membered ring or a 6-membered ring from the viewpoint of ease of synthesis and light resistance. Specific examples include, for example, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, thiazole ring, oxazole ring, imidazole ring, triazole ring, 1,2,4-thiadiazole ring, 1,3,4-thiadiazole. And a ring, 1,2,4-oxadiazole ring, 1,3,4-oxadiazole ring, isoxazole ring, isothiazole ring and the like. The ring formed by Q ¹ may have a substituent. Examples of the substituent include the above-described substituents, and adjacent groups may be bonded to form a ring. Examples of the ring formed include a quinoline ring, a benzothiazole ring, a benzoxazole ring, a benzimidazole ring, and the like, and these may further have a substituent.

The nitrogen-containing heterocycle formed by Q ¹ is preferably a pyridine ring, a thiazole ring, an oxazole ring, an imidazole ring, or any one of the following partial structures (C-1) or (C-2).

[上記において、Ｒ¹〜Ｒ⁶は、各々独立に水素原子または置換基を表し、＊は炭素原子との結合位置を表す。]

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ]

In the partial structure (C-1), R ¹ and R ² each independently represent a hydrogen atom or a substituent, and may be bonded to each other to form a ring. Although it does not specifically limit as a substituent, The substituent quoted by description of General formula (1) is mentioned. R ¹ and R ² are preferably bonded to each other to form a benzene ring. The benzene ring may be substituted with the substituent.

R ³ represents a hydrogen atom or a substituent. R ³ is not particularly limited, and examples thereof include an alkyl group (including a cycloalkyl group and a bicycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, an aryl group, a heterocyclic group, Examples thereof include a sulfamoyl group, an alkyl and arylsulfonyl group, an acyl group, an aryloxycarbonyl group, an alkoxycarbonyl group, and a carbamoyl group.
R ³ is preferably an alkyl group, aryl group, heterocyclic group, sulfamoyl group, alkyl, or arylsulfonyl group, more preferably an alkyl group, aryl group, or heterocyclic group, and still more preferably an alkyl group. .

R ⁴ and R ⁵ in the partial structure (C-2) have the same meanings as R ¹ and R ^{2 in} the partial structure (C-1), and details such as preferred ranges are also the same.

R ⁶ in the partial structure (C-2) has the same definition as R ³ in the partial structure (C-1), and details such as a preferred range are also the same.

The nitrogen-containing heterocycle formed by Q ¹ is more preferably a pyridine ring, a benzothiazole ring, a benzoxazole ring, or any one of the partial structures (C-1) or (C-2), It is further preferably a benzothiazole ring or a benzoxazole ring, more preferably a pyridine ring or a benzothiazole ring, and most preferably a pyridine ring.

G ¹ represents a heterocyclic ring or a carbocyclic ring, and is preferably a heterocyclic group. The heterocyclic group or carbocyclic group may have a substituent or may be condensed. From the viewpoint of improving solubility, it preferably has a substituent, and more preferably a monocycle having a substituent. Although it does not specifically limit as a substituent, The substituent illustrated by description of the substituent of General formula (1) is mentioned.

When G ¹ is a heterocyclic group, the heterocyclic ring is not particularly limited. For example, a pyrazole ring, a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, a thiazole ring, an oxazole ring, an isothiazole ring, an isoxazole ring, 1,3,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole ring, pyridine ring, pyrazine ring, pyrimidine Ring, pyridazine ring, and triazine ring are preferable, and pyrazole ring, imidazole ring, isothiazole ring, isoxazole ring, 1,3,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2 , 4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole ring, more preferably pyrazole Imidazole ring, isoxazole ring, 1,3,4-thiadiazole ring, 1,2,4-thiadiazole ring, triazole ring, more preferably pyrazole ring, isoxazole ring, 1,3,4-thiadiazole ring. And particularly preferably a pyrazole ring.

When G ¹ is a carbocyclic group, it preferably has an atom covalently or coordinately bonded to a metal ion on the substituent of G ¹ . When G ¹ is a carbocyclic group, it is preferably a phenyl group.

When G ¹ is a heterocyclic group, G ¹ has an atom that is covalently or coordinated to a metal ion on the ring or on a substituent contained in G ¹ .

[上記において、＊は−Ｎ＝Ｎ−基との結合位置を表し、Ｑ²は隣り合う炭素原子および窒素原子とともに含窒素複素環を形成する原子群を表す。]
であるアゾ色素、即ち、下記一般式（２）で表されるアゾ色素を挙げることができる。

As a preferred embodiment of the azo dye represented by the general formula (1), G1 in the general formula (1) is the following partial structure:

[In the above, * represents the bonding position to the —N═N— group, and Q ² represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. ]
And azo dyes represented by the following general formula (2).

In the general formula (2), Q ^1, E ¹ is the general formula (1) is Q ^1, E ¹ and synonymous, is the same details of the preferred range, and the like.

Q ² represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. Although it does not specifically limit as said heterocyclic ring, For example, a pyrazole ring, an imidazole ring, a thiazole ring, an oxazole ring, an isothiazole ring, an isoxazole ring, 1,3,4-thiadiazole ring, 1,3,4-oxadiazole Ring, 1,2,4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, preferably pyrazole ring, imidazole ring , Isothiazole ring, isoxazole ring, 1,3,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole More preferably a pyrazole ring, imidazole ring, isoxazole ring, 1,3,4-thiadi. Tetrazole ring, 1,2,4-thiadiazole ring, a triazole ring, more preferably a pyrazole ring, an isoxazole ring, a 1,3,4-thiadiazole ring, particularly preferably a pyrazole ring.

  A more preferred embodiment of the azo dye represented by the general formula (1) includes an azo dye represented by the following general formula (3).

In general formula (3), E ² represents a cyano group or an alkoxycarbonyl group. The details of the alkoxycarbonyl group are as described for the alkoxycarbonyl group which can be represented by E ¹ . E ² is more preferably an alkyloxycarbonyl group having 2 to 12 carbon atoms or a cyano group, and a cyano group is more preferable from the viewpoint of recording characteristics.

Q ³ represents an atomic group that forms any of the pyridine ring, the oxazole ring, the thiazole ring, and the partial structure (C-1) or (C-2) together with the adjacent carbon atom and nitrogen atom. It may have a substituent and may be condensed. The nitrogen-containing heterocycle formed by Q ³ is preferably any of a pyridine ring, an oxazole ring, and a thiazole ring, more preferably any of a pyridine ring, a benzoxazole ring, and a benzothiazole ring, More preferred is a pyridine ring.

Q ⁴ represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. Although it does not specifically limit as a heterocyclic ring, For example, a pyrazole ring, an imidazole ring, a thiazole ring, an oxazole ring, an isothiazole ring, an isoxazole ring, a 1,3,4-thiadiazole ring, a 1,3,4-oxadiazole ring 1,2,4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, preferably pyrazole ring, imidazole ring, Isothiazole ring, isoxazole ring, 1,3,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,4-thiadiazole ring, 1,2,4-oxadiazole ring, triazole ring And more preferably pyrazole ring, imidazole ring, isoxazole ring, 1,3,4-thiadiazo Le ring, 1,2,4-thiadiazole ring, a triazole ring, more preferably a pyrazole ring, an isoxazole ring, a 1,3,4-thiadiazole ring, particularly preferably a pyrazole ring.

[上記において、＊は−Ｎ＝Ｎ−基との結合位置を表し、Ｒ⁷〜Ｒ⁹は各々独立に水素原子または置換基を表す。]
で表されるアゾ色素、即ち、下記一般式（４）で表されるアゾ色素であることが更に好ましい。 In the azo dye represented by the general formula (3), the ring structure formed together with the carbon atom and the nitrogen atom adjacent to Q ⁴ in the general formula (3) has the following partial structure:

[In the above, * represents a bonding position with —N═N— group, and R ^{7 to} R ⁹ each independently represents a hydrogen atom or a substituent. ]
More preferably, it is an azo dye represented by the following general formula (4).

Formula (4) Q ^3, E ² in the general formula (3) in a Q ^3, E ² and synonymous, is the same details of the preferred range, and the like.

R ^{7 to} R ⁹ each independently represents a hydrogen atom or a substituent. No particular limitation is imposed on the substituent, for R ^7, R ^8, wherein such substituents listed for R ¹ can be mentioned, for R ^9, include substituents exemplified in the R ³ .

R ⁷ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryloxycarbonyl group having 7 to 10 carbon atoms, A substituted or unsubstituted alkylaminocarbonyl group having 2 to 10 carbon atoms, a substituted or unsubstituted arylaminocarbonyl group having 7 to 10 carbon atoms, a substituted or unsubstituted alkylsulfonyl group having 1 to 10 carbon atoms, a carbon number of 6 Is preferably a group selected from a substituted or unsubstituted arylsulfonyl group having 10 to 10 carbon atoms, a cyano group, a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms, and a substituted or unsubstituted carbon atom having 7 to 10 carbon atoms. Aryloxycarbonyl group, substituted or unsubstituted alkylsulfonyl group having 1 to 10 carbon atoms, carbon number 6 It is more preferably a group selected from 10 substituted or unsubstituted arylsulfonyl groups and cyano groups, a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms, and a substituted or unsubstituted group having 7 to 10 carbon atoms. The aryloxycarbonyl group is more preferably a group selected from a cyano group, and a cyano group is particularly preferable.

R ⁸ is preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, and a substituted or unsubstituted group having 1 to 10 carbon atoms from the viewpoint of solubility. An unsubstituted alkyl group and a substituted or unsubstituted aryl group having 6 to 10 carbon atoms are more preferable. The alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 2 to 4 carbon atoms, and still more preferably an alkyl group having 3 or 4 carbon atoms.

R ⁹ is preferably any one of a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a sulfamoyl group, an alkyl and an arylsulfonyl group, and any one of a hydrogen atom, an alkyl group, an aryl group, and a heterocyclic group More preferably, it is more preferably a hydrogen atom.

The azo dye represented by the general formula (4) is more preferably represented by the following general formula (5).

The azo dye represented by the general formula (5) is an azo dye in which R ⁹ in the general formula (4) is a hydrogen atom. E ² , Q ³ , R ⁷ and R ⁸ in the general formula (5) have the same meanings as those in the general formula (4), and details such as preferred ranges are also the same. Examples of the azo metal complex dye contained in the recording layer of the optical information recording medium of the present invention include the azo dye represented by the general formula (5), and copper ions having the same number or more than the number of the azo dye. And an azo metal complex dye containing at least two copper ions in one molecule is particularly preferable.

  Specific examples of the azo dye represented by the general formula (1), the general formula (2), the general formula (3), and / or the general formula (4) are shown below. However, the present invention is not limited to these.

  Examples of the general synthesis method of the azo dyes represented by the general formulas (1) to (4) include methods described in JP-A Nos. 61-36362 and 2006-57076. However, the reaction is not limited to this, and other reaction solvents and acids may be used, and the coupling reaction may be performed in the presence of a base (for example, sodium acetate, pyridine, sodium hydroxide, etc.). Specific examples of the synthesis method of the azo dye are shown below.

The azo metal complex dye which is a complex of the azo dye represented by the general formula (1) and the metal ion can be obtained by reacting the azo dye represented by the general formula (1) with the metal ion, It preferably belongs to any of the following (A), (B), and (C).
(A) pentanuclear azo metal complex dye formed by four azo dye molecules and five metal ions (B) azo metal complex dye formed by two azo dye molecules and one metal ion (C) one azo dye molecule (A) or (B) is more preferable than the azo metal complex dye formed with one metal ion, and (A) is more preferable.

  A preferred embodiment of the azo metal complex color is a complex of the azo dye represented by the general formula (1) and a transition metal ion having the same number or more than the number of the azo dye, and in one molecule. An azo metal complex dye containing two or more transition metal ions can also be mentioned. Here, a plurality of transition metal ions contained in one molecule of the azo metal complex dye may be the same or different from each other. When a plurality of azo dyes are contained in one molecule of the azo metal complex dye, a plurality of azo dyes are contained. The dyes may be the same or different. As such an azo metal complex dye, the azo metal complex dye belonging to (A) is preferable.

  As a general method of the azo metal complex belonging to any one of (A), (B), and (C), an azo dye and a metal salt (including a metal complex and a metal oxide salt) are used in an organic solvent or in water. Alternatively, a method of stirring in the mixed solution can be mentioned. A base may be added as necessary. However, the type of metal salt, the type of base, the type of organic solvent or a mixture thereof, the reaction temperature, etc. are not limited. The kind of base is not particularly limited. In the present invention, the reaction is preferably carried out in the presence of a base.

  Specific examples of the method for synthesizing the azo metal complex dye include alcohol solvents such as methanol and ethanol as reaction solvents, amines and amidines as bases (for example, DBU (1,8-diazabicyclo [5.4.0] -7). -Undecene) etc.), guanidine, inorganic base (NaOH etc.) etc., and the method of making it heat-reflux is mentioned. However, it is not limited to these. The reaction conditions such as the reaction solvent, the concentration and mixing ratio of the azo dye and metal salt in the reaction solution, the reaction temperature and the reaction time may be set as appropriate.

  The structure of the azo metal complex can be confirmed by known methods such as ESI-MS, MALDI-MS, ICP-OES, and X-ray structural analysis.

  Specific examples of the azo metal complex dye belonging to (A) and (B) are shown below. However, the present invention is not limited to these.

In general, a metal complex may change the coordination structure and the valence of a metal ion depending on the state of existence (solution, powder, etc.). In the solution state, the solvent molecule may become a ligand or the valence of the metal ion may change due to the interaction between the solvent molecule and the metal ion. Regarding the change in the valence of the metal ion, for example, it is considered that even if it is a complex of Cu ^{2+ in} a powder state, it becomes Cu ⁺ in the presence of a solvent. It is conceivable that the type of counter ion may change due to these changes in the coordination structure.

  The coordination structure of the azo metal complex belonging to (A) is the same as that of the following analogs. However, the constituent elements in the molecule are not limited to azo dyes and metal ions, and include cases in which coexisting anion species, cation species, and solvent molecules are added. The X-ray structural analysis of the azo metal complex obtained by reacting the compound (A-0), which is an analog of the azo dye represented by the general formula (1), with copper ions is shown below. The structure will be described.

  When the compound (A-0) forms a metal complex with a copper ion, the structure of the compound (A-0) as a ligand is the compound (A-1) indicated by an arrow in (1) to (3). Bonds with copper ions in position. And when this ligand forms a complex with a copper ion, it becomes a metal chelate in which five copper ions and four ligands are bonded. These five copper ions are referred to as first copper ion to fifth copper ion, and the four ligands are referred to as ligand 1 to ligand 4, and their positions (1) to (3) are arranged. When ligand 1 is called ligand 1 (1) to ligand 1 (3), and ligand 2 is called ligand 2 (1) to ligand 2 (3), this metal chelate is Ligand 1 (1) and Ligand 2 (2) are bonded to the first copper ion, and Ligand 1 (2) and Ligand 3 (1) are bonded to the second copper ion. Ligand 2 (1) and ligand 4 (2) are bonded to the third copper ion, and Ligand 3 (2) and ligand 4 (1) are bonded to the fourth copper ion. The ligand 1 (3), the ligand 2 (3), the ligand 3 (3) and the arrangement of the first copper ion to the fifth copper ion located in the center surrounded by the fourth copper ion. It was confirmed that the structure of the ligand 4 (3) was combined.

  The optical information recording medium of the present invention has a recording layer containing at least one azo metal complex dye which is a complex of an azo dye represented by the general formula (1) and a metal ion. The recording layer can contain one or more of the azo metal complex dyes. The content of the azo metal complex dye in the recording layer is, for example, in the range of 1 to 100% by mass, preferably in the range of 70 to 100% by mass, and more preferably 80% with respect to the total mass of the recording layer. It is the range of -100 mass%, Most preferably, it is the range of 90-100 mass%.

  The optical information recording medium of the present invention has a recording layer containing an azo metal complex dye, which is a complex of an azo dye represented by the general formula (1) and a metal ion, on a substrate (a pregroove with a track pitch of 50 to 500 nm). As long as it has at least one layer on the surface), the recording layer may have two or more layers. Alternatively, it is possible to have a recording layer other than the recording layer containing the azo metal complex dye. In the recording layer containing the azo metal complex dye, when another dye is used in combination as a recording dye, the ratio of the azo metal complex dye to the total dye component is preferably 70 to 100% by mass, and 80 to 100%. More preferably, it is mass%.

  In the present invention, when a dye other than the azo metal complex dye is used as the dye component, the dye preferably has an absorption in a short wavelength region of, for example, a wavelength of 440 nm or less. Examples of such dyes include, but are not limited to, azo dyes, azo metal complex dyes, phthalocyanine dyes, oxonol dyes, cyanine dyes, squarylium dyes, and the like.

  In the optical information recording medium of the present invention, the recording layer containing the azo metal complex dye is a layer capable of recording information by irradiation with laser light. Here, “recording of information by laser light irradiation” means that the portion of the recording layer irradiated with the laser light changes its optical characteristics. The change in the optical characteristics is caused by the portion of the recording layer irradiated with the laser light absorbing the light and locally raising the temperature, causing a physical or chemical change (for example, generation of pits). It is thought that. Reading (reproduction) of information recorded on the recording layer does not change from a portion (recording portion) where the optical characteristics of the recording layer have changed by, for example, irradiating laser light having the same wavelength as the recording laser light. This can be done by detecting a difference in optical characteristics such as reflectance from the portion (unrecorded portion). The azo metal complex dye of the present invention has absorptivity with respect to laser light of 440 nm or less, for example. As described above, the optical information recording medium of the present invention having a recording layer containing a metal complex compound having an absorptivity in a short wavelength region can be recorded by a short wavelength laser such as a Blu-ray optical disk using a 405 nm blue laser. It is suitable as a large-capacity optical disk. The method for recording information on the optical information recording medium of the present invention will be described later.

  The optical information recording medium of the present invention has a recording layer containing at least the azo metal complex dye, preferably on a substrate, and may further have a light reflecting layer, a protective layer, etc. in addition to the recording layer. it can.

As the substrate used in the present invention, various materials used as substrate materials for conventional optical information recording media can be arbitrarily selected and used. As the substrate, a transparent disk-shaped substrate is preferably used.
Specifically, glass; acrylic resin such as polycarbonate and polymethyl methacrylate; vinyl chloride resin such as polyvinyl chloride and vinyl chloride copolymer; epoxy resin; amorphous polyolefin; polyester; metal such as aluminum; These may be used together if desired.
Among the materials, thermoplastic resins such as amorphous polyolefin and polycarbonate are preferable, and polycarbonate is particularly preferable from the viewpoints of moisture resistance, dimensional stability, and low price. When these resins are used, the substrate can be manufactured by injection molding.
The thickness of the substrate is generally in the range of 0.7 to 2 mm, preferably in the range of 0.9 to 1.6 mm, and more preferably 1.0 to 1.3 mm.
An undercoat layer can also be formed on the substrate surface on the side where the light reflecting layer described later is provided for the purpose of improving flatness and adhesion.

  On the surface of the substrate on which the recording layer is formed, a guide groove for tracking or unevenness (pre-groove) representing information such as an address signal is formed. The track pitch of the pregroove is in the range of 50 to 500 nm. The track pitch of the pregroove is in the range of 50 to 500 nm. If the track pitch is 50 nm or more, the pregroove can be formed accurately, and the occurrence of crosstalk can be avoided. If the track pitch is 500 nm or less, high-density recording can be performed. The optical information recording medium of the present invention uses a substrate on which a narrower track pitch is formed compared to CD-R and DVD-R in order to achieve higher recording density. Details such as a preferable range of the track pitch will be described later.

  As a preferred embodiment of the optical information recording medium of the present invention, a write-once recording layer containing a dye and a cover layer having a thickness of 0.01 to 0.5 mm are formed on a substrate having a thickness of 0.7 to 2 mm. And an optical information recording medium (hereinafter referred to as “mode (1)”) in order from the side.

In aspect (1), it is preferable that the track pitch of the pregroove formed on the substrate is 50 to 500 nm, the groove width is 25 to 250 nm, and the groove depth is 5 to 150 nm.
Hereinafter, the optical information recording medium of aspect (1) will be described in more detail. However, the optical information recording medium of the present invention is not limited to the aspect (1).

[Optical Information Recording Medium of Aspect (1)]
The optical information recording medium of aspect (1) is an aspect having at least a substrate, a write-once recording layer, and a cover layer. The optical information recording medium of aspect (1) is suitable as a Blu-ray recording medium. In the Blu-ray system, information is recorded and reproduced by irradiating a laser beam from the cover layer side, and a reflective layer is usually provided between the substrate and the recording layer. Therefore, the laser beam is irradiated to the recording layer from the surface opposite to the surface facing the reflective layer.

A specific example of the optical information recording medium of aspect (1) is shown in FIG. A first optical information recording medium 10A shown in FIG. 1 has a first light reflecting layer 18, a first write-once recording layer 14, a barrier layer 20, and a first adhesive layer or a first adhesive on a first substrate 12. It has the layer 22 and the cover layer 16 in this order.
Below, the material which comprises these is demonstrated sequentially.

In the substrate of the substrate mode (1), pregrooves (guide grooves) having a shape in which the track pitch, groove width (half width), groove depth, and wobble amplitude are all within the following ranges are formed. . This pre-groove is provided to achieve a higher recording density than CD-R and DVD-R. For example, the optical information recording medium of the present invention is used as a medium corresponding to a blue-violet laser. It is suitable for use.

  The track pitch of the pregroove is in the range of 50 to 500 nm. If the track pitch is 50 nm or more, the pregroove can be formed accurately, and the occurrence of crosstalk can be avoided. If the track pitch is 500 nm or less, high-density recording can be performed. The track pitch of the pregroove is preferably 100 nm or more and 420 nm or less, more preferably 200 nm or more and 370 nm or less, and further preferably 260 nm or more and 330 nm or less.

  The groove width (half width) of the pregroove is in the range of 25 to 250 nm, preferably 50 nm or more and 240 nm or less, more preferably 80 nm or more and 230 nm or less, and further preferably 100 nm or more and 220 nm or less. . If the groove width of the pregroove is 25 nm or more, the groove can be sufficiently transferred at the time of molding, and further, an increase in the error rate at the time of recording can be suppressed. Furthermore, it is possible to avoid the occurrence of crosstalk due to the spread of pits formed during recording.

  The groove depth of the pregroove is in the range of 5 to 150 nm. If the groove depth of the pregroove is 5 nm or more, a sufficient recording modulation degree can be obtained, and if it is 150 nm or less, a high reflectance can be obtained. The groove depth of the pregroove is preferably 10 nm to 85 nm, more preferably 20 nm to 80 nm, and still more preferably 28 nm to 75 nm.

The groove inclination angle of the pregroove is preferably 80 ° or less, more preferably 75 ° or less, still more preferably 70 ° or less, and particularly preferably 65 ° or less. preferable. Further, the lower limit value is preferably 20 ° or more, more preferably 30 ° or more, and further preferably 40 ° or more.
If the groove inclination angle of the pregroove is 20 ° or more, a sufficient tracking error signal amplitude can be obtained, and if it is 80 ° or less, the moldability is good.

In the write-once recording layer of write-once recording layer mode (1), a dye is dissolved in a suitable solvent together with a binder or the like or without using a binder, and a coating solution is prepared. Or after apply | coating on the light reflection layer mentioned later and forming a coating film, it can form by drying. Here, the write-once recording layer may be a single layer or a multilayer. In the case of a multilayer structure, the step of applying the coating liquid is performed a plurality of times.
The concentration of the dye in the coating solution is generally in the range of 0.01 to 15% by mass, preferably in the range of 0.1 to 10% by mass, more preferably in the range of 0.5 to 5% by mass, most preferably. It is the range of 0.5-3 mass%.

Solvents used for preparing the coating solution include, for example, esters such as butyl acetate, ethyl lactate and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane and chloroform. Amides such as dimethylformamide; hydrocarbons such as methylcyclohexane; ethers such as tetrahydrofuran, ethyl ether and dioxane; alcohols such as ethanol, n-propanol, isopropanol and n-butanol diacetone alcohol; 2,2,3,3- Fluorinated solvents such as tetrafluoro-1-propanol; glycol agents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether And the like can be given; le compound.
Solvents can be used alone or in combination of two or more in consideration of the solubility of the dye used. In the coating solution, various additives such as a binder, an antioxidant, a UV absorber, a plasticizer, and a lubricant may be added according to the purpose.

Examples of the coating method include a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, and a screen printing method. As a coating method, a spin coating method is preferable.
At the time of application, the temperature of the coating solution is preferably in the range of 23 to 50 ° C, more preferably in the range of 24 to 40 ° C, and particularly preferably in the range of 23 to 50 ° C.

The thickness of the write-once recording layer is preferably 300 nm or less, more preferably 250 nm or less, even more preferably 200 nm or less, and 180 nm or less on the land (the convex portion in the substrate). It is particularly preferred. The lower limit is preferably 1 nm or more, more preferably 3 nm or more, still more preferably 5 nm or more, and particularly preferably 7 nm or more.
The thickness of the write-once recording layer is preferably 400 nm or less, more preferably 300 nm or less, and even more preferably 250 nm or less on the groove (the concave portion in the substrate). The lower limit is preferably 10 nm or more, more preferably 20 nm or more, and further preferably 25 nm or more.
Further, the ratio of the thickness of the write-once recording layer on the land / the thickness of the write-once recording layer on the groove is preferably 0.1 or more, more preferably 0.13 or more, and More preferably, it is 15 or more, and it is especially preferable that it is 0.17 or more. The upper limit is preferably less than 1, more preferably 0.9 or less, still more preferably 0.85 or less, and particularly preferably 0.8 or less.

The write-once recording layer can contain various anti-fading agents in order to further improve the light resistance of the write-once recording layer. As the anti-fading agent, a singlet oxygen quencher is generally used. In the present invention, further improvement in light resistance can be expected by mixing the singlet oxygen quencher. As the singlet oxygen quencher, those described in publications such as known patent specifications can be used.
Specific examples thereof include JP-A Nos. 58-175893, 59-81194, 60-18387, 60-19586, 60-19587, and 60-35054. 60-36190, 60-36191, 60-44554, 60-44555, 60-44389, 60-44390, 60-54892, JP-A-60-47069, JP-A-63-209995, JP-A-4-25492, JP-B-1-38680, JP-A-6-26028, etc., German Patent No. 350399, and Japan Examples include those described in Chemical Society Journal, October 1992, page 1141.
The use amount of the antifading agent such as the singlet oxygen quencher is usually in the range of 0.1 to 50% by weight, preferably in the range of 0.5 to 45% by weight, based on the amount of the dye. Preferably, it is the range of 3-40 mass%, Most preferably, it is the range of 5-25 mass%.

The cover layer of the cover layer mode (1) is usually bonded on the write-once recording layer described above or on the barrier layer as shown in FIG. 1 via an adhesive or an adhesive.
The cover layer is not particularly limited as long as it is a transparent film, but is not limited to acrylic resins such as polycarbonate and polymethyl methacrylate; vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymers; epoxy resins; amorphous polyolefins Polyester; cellulose triacetate or the like is preferably used, and among them, polycarbonate or cellulose triacetate is more preferably used.
Note that “transparent” means that the transmittance is 80% or more with respect to light used for recording and reproduction.

Further, the cover layer may contain various additives as long as the effects of the present invention are not hindered. For example, a UV absorber for cutting light having a wavelength of 400 nm or less and / or a dye for cutting light having a wavelength of 500 nm or more may be contained.
Further, as the surface physical properties of the cover layer, it is preferable that the surface roughness is 5 nm or less for both the two-dimensional roughness parameter and the three-dimensional roughness parameter.
Further, from the viewpoint of the concentration of light used for recording and reproduction, the birefringence of the cover layer is preferably 10 nm or less.

The thickness of the cover layer can be appropriately determined according to the wavelength and NA of the laser beam irradiated for recording and reproduction, but in the present invention, it is within the range of 0.01 to 0.5 mm. It is preferable that the thickness is in the range of 0.05 to 0.12 mm.
The total thickness of the cover layer and the layer made of an adhesive or a pressure-sensitive adhesive is preferably 0.09 to 0.11 mm, and more preferably 0.095 to 0.105 mm.
The light incident surface of the cover layer may be provided with a protective layer (hard coat layer 44 in the embodiment shown in FIG. 1) for preventing the light incident surface from being damaged when the optical information recording medium is manufactured. Good.

In order to bond the cover layer and the write-once recording layer or barrier layer, an adhesive layer or an adhesive layer can be provided between the two layers.
As an adhesive used for the adhesive layer, it is preferable to use a UV curable resin, an EB curable resin, a thermosetting resin, or the like.
When a UV curable resin is used as an adhesive, the UV curable resin may be used as it is or dissolved in an appropriate solvent such as methyl ethyl ketone or ethyl acetate to prepare a coating solution, which may be supplied from the dispenser to the barrier layer surface. . Further, in order to prevent warpage of the produced optical information recording medium, it is preferable to use a UV curable resin having a low curing shrinkage rate as the UV curable resin constituting the adhesive layer. Examples of such UV curable resins include UV curable resins such as “SD-640” manufactured by Dainippon Ink & Chemicals, Inc.

The method for forming the adhesive layer is not particularly limited, but a predetermined amount of adhesive is applied on the surface (bonded surface) of the barrier layer or write-once recording layer, and a cover layer is placed thereon, followed by spin coating. It is preferable that the adhesive is cured after being spread uniformly between the bonded surface and the cover layer.
The thickness of the adhesive layer is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 50 μm, and still more preferably in the range of 1 to 30 μm.

As the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer, for example, an acrylic, rubber-based, or silicon-based pressure-sensitive adhesive can be used. From the viewpoint of transparency and durability, an acrylic pressure-sensitive adhesive is preferred. As an acrylic adhesive, 2-ethylhexyl acrylate, n-butyl acrylate and the like are the main components, and in order to improve cohesion, short-chain alkyl acrylates and methacrylates such as methyl acrylate, ethyl acrylate, methyl methacrylate, It is preferable to use a copolymer of acrylic acid, methacrylic acid, an acrylamide derivative, maleic acid, hydroxylethyl acrylate, glycidyl acrylate, or the like that can serve as a crosslinking point with a crosslinking agent. The glass transition temperature (Tg) and the crosslinking density can be changed by appropriately adjusting the mixing ratio of the main component, the short chain component and the component for adding a crosslinking point and the kind of the component.
The glass transition temperature (Tg) is preferably 0 ° C. or lower, more preferably −15 ° C. or lower, and further preferably −25 ° C. or lower.
The glass transition temperature (Tg) can be measured by DSC (Differential Scanning Calorimetry) method using DSC6200R manufactured by Seiko Instruments Inc.

  As a method for preparing the pressure-sensitive adhesive, for example, methods described in JP-A No. 2003-217177, JP-A No. 2003-203387, JP-A No. 9-147418 and the like can be used.

The method of forming the adhesive layer is not particularly limited, but after applying a predetermined amount of the adhesive uniformly on the surface of the barrier layer or write-once recording layer (bonded surface), and placing the cover layer thereon, It may be cured, or beforehand, a predetermined amount of pressure-sensitive adhesive is uniformly applied to one side of the cover layer to form a pressure-sensitive adhesive coating, and the coating is bonded to the surface to be bonded, It may be cured.
Moreover, you may use the commercially available adhesive film in which the adhesion layer was previously provided for the cover layer.
The thickness of the adhesive layer is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 50 μm, and still more preferably in the range of 10 to 30 μm.
The cover layer may be formed by spin coating using a UV curable resin.

The optical information recording medium of the other layer mode (1) may have other arbitrary layers in addition to the essential layers as long as the effects of the present invention are not impaired. As other optional layers, for example, a label layer having a desired image formed on the back surface of the substrate (the non-formation surface side opposite to the side on which the write-once recording layer is formed) or the substrate and write-once type A light reflection layer (details will be described later) provided between the recording layer, a barrier layer (details will be described later) provided between the write-once recording layer and the cover layer, the light reflection layer and the write-once recording layer, And an interface layer provided between the two. Here, the label layer can be formed using an ultraviolet curable resin, a thermosetting resin, a heat drying resin, or the like.
The essential and optional layers described above may be a single layer or a multilayer structure.

  In the optical information recording medium of aspect (1), a light reflecting layer is formed between the substrate and the write-once recording layer in order to increase the reflectivity with respect to the laser beam and to provide the function of improving the recording / reproducing characteristics. It is preferable.

The light reflecting layer can be formed on the substrate by, for example, vacuum deposition, sputtering or ion plating with a light reflecting material having a high reflectance with respect to the laser beam.
The thickness of the light reflecting layer is generally in the range of 10 to 300 nm, and preferably in the range of 30 to 200 nm.
The reflectance is preferably 70% or more.

  As a light reflective material having a high reflectance, Mg, Se, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Ru, Rh, Pd , Ir, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Si, Ge, Te, Pb, Po, Sn, Bi, and the like, and metal and semi-metal or stainless steel. These light reflecting materials may be used alone, or may be used in combination of two or more kinds or as an alloy. Among these, Cr, Ni, Pt, Cu, Ag, Au, Al, and stainless steel are preferable. Particularly preferred is Au, Ag, Al or an alloy thereof, and most preferred is Au, Ag or an alloy thereof.

Barrier layer (intermediate layer)
In the optical information recording medium of aspect (1), it is preferable to form a barrier layer between the write-once recording layer and the cover layer as shown in FIG.
The barrier layer can be provided for improving the storage stability of the write-once recording layer, improving the adhesion between the write-once recording layer and the cover layer, adjusting the reflectance, adjusting the thermal conductivity, and the like.
The material used for the barrier layer is not particularly limited as long as it is a material that transmits light used for recording and reproduction and can express the above functions. For example, in general, It is a material with low gas and moisture permeability and is preferably a dielectric. Specifically, Zn, Si, Ti, Te , Sn, Mo, Ge, Nb, nitrides such as Ta, oxides, carbides, material consisting of sulfide _{Preferably, MoO 2, GeO 2, TeO} , SiO 2 , TiO ₂ , ZnO, SnO ₂ , ZnO—Ga ₂ O ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ are preferable, SnO ₂ , ZnO—Ga ₂ O ₃ , SiO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ Is more preferable.

The barrier layer can be formed by a vacuum film forming method such as vacuum deposition, DC sputtering, RF sputtering, or ion plating. Among these, it is more preferable to use sputtering.
The thickness of the barrier layer is preferably in the range of 1 to 200 nm, more preferably in the range of 2 to 100 nm, and still more preferably in the range of 3 to 50 nm.

[Information recording method]
Furthermore, the present invention relates to an information recording method for recording information on a recording layer of the optical information recording medium of the present invention by irradiating the optical information recording medium of the present invention with a laser beam having a wavelength of 440 nm or less.

For example, the recording of information on the optical information recording medium of the preferred mode (1) described above is performed as follows.
First, recording light such as semiconductor laser light is irradiated from the protective layer side while rotating the optical information recording medium at a constant linear velocity (for example, 0.5 to 10 m / sec) or a constant angular velocity. By this light irradiation, the optical characteristics of the laser light irradiated portion change and information is recorded. In the embodiment shown in FIG. 1, a recording laser beam 46 such as a semiconductor laser beam is irradiated from the cover layer 16 side via a first objective lens 42 (for example, a numerical aperture NA is 0.85). By irradiation with the laser beam 46, the write-once recording layer 14 absorbs the laser beam 46 and the temperature rises locally, causing a physical or chemical change (for example, generation of pits) to change its optical characteristics. Thus, it is considered that information is recorded.

  In the information recording method of the present invention, information is recorded by irradiating a laser beam having a wavelength of 440 nm or less. As the recording light, a semiconductor laser light having an oscillation wavelength in the range of 440 nm or less is preferably used. As a preferable light source, a blue-violet semiconductor laser light having an oscillation wavelength in the range of 390 to 415 nm, an infrared having a central oscillation wavelength of 850 nm is used. A blue-violet SHG laser beam having a central oscillation wavelength of 425 nm, which is a half wavelength of the semiconductor laser beam using an optical waveguide device, can be mentioned. In particular, it is preferable to use a blue-violet semiconductor laser beam having an oscillation wavelength in the range of 390 to 415 nm in terms of recording density. The information recorded as described above is reproduced by irradiating the semiconductor laser beam from the substrate side or the protective layer side while rotating the optical information recording medium at the same constant linear velocity as above and detecting the reflected light. Can be performed.

[Azo metal complex dye]
Furthermore, the present invention is a complex of the azo dye represented by the general formula (5) and a copper ion having the same number or more than the number of the azo dye, and two or more in one molecule. The present invention relates to an azo metal complex dye containing copper ions. The azo metal complex dye of the present invention preferably belongs to the above (A).

  The azo metal complex dye of the present invention can be used in various applications such as pigments, photographic materials, UV absorbing materials, color filter dyes, and color conversion filters. Since the azo metal complex dye of the present invention is excellent in optical information recording, in particular, recording characteristics by irradiation with a short wavelength laser beam, and further excellent in light resistance and storage stability in a solution, it is preferably a light having a dye-containing recording layer. Used as a recording layer dye in an information recording medium. The details of the azo metal complex dye of the present invention and the production method thereof are as described above.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples.

  Specific examples of the synthesis method of the azo dye represented by the general formula (1) are shown below, but the present invention is not limited to these methods.

[Synthesis of Compound (L-1)]

8 ml of acetic acid and 16 ml of propionic acid were poured into a 200 ml Erlenmeyer flask, and 5.55 g of hydrochloric acid (35 to 37%) was slowly added dropwise under ice cooling. The solution was cooled to 0 to 5 ° C. in an ice bath, and a solution prepared by dissolving 1.26 g of NaNO ₂ in 2 ml of water was slowly added dropwise thereto, followed by stirring at 0 to 5 ° C. for 30 minutes. This acidic solution was gradually added to a solution obtained by mixing 1.95 ml of compound (2) kept at 0 to 5 ° C. under ice cooling and 50 ml of methanol, and stirred for 1 hour. After returning to room temperature and stirring for 2 hours, the precipitate was filtered and washed with a minimum amount of methanol. The obtained solid was recrystallized from methanol and dried to obtain 2.95 g of Compound (L-1). The compound was identified by 300 MHz ¹ H-NMR.
¹ H-NMR (CDCl ₃ ) [ppm]; δ 11.71 (1H, s), 11.20 (1H, s), 8.65 (1H, d), 7.83-7.79 (1, m), 7.31-7.27 (1 H, m ), 1.54-1.17 (9H, m)

(L-2), (L-4), (L-7), and (L-8) were synthesized by the same method as the synthesis of compound (L-1) described above. Various azo metal complex dyes described in the present invention can be synthesized in the same manner. The compound was identified by 400 MHz ¹ H-NMR. The NMR spectrum data is shown below.

(L-2) ¹ H-NMR (DMSO-d6) [ppm]; δ13.17 (1H, Br), 12.90 (1H, Br), 8.10 (1H, d), 8.03 (1H, d), 7.54 ( 1H, dd), 7.46 (1H, dd), 1.42 (9H, s)
(L-4) ¹ H-NMR (DMSO-d6) [ppm]; δ13.50 (1H, s), 13.15 (1H, s), 7.97 (1H, d), 7.89 (1H, d), 7.59- 7.50 (2H, m), 4.32 (2H, q), 1.42 (9H, s), 1.34 (3H, t)
(L-7) ¹ H-NMR (DMSO-d6) [ppm]; (mixture) δ 1.34 (1H, br), 10.23 (1H, br), 7.90 (1H, br), 7.70-6.71 (9H, m), 4.53 (br), 4.03 (q), 1.50-0.95 (12H, m)
(L-8) ¹ H-NMR (DMSO-d6) [ppm]; (mixture) δ 13.20 (br), 13.01 (s), 12.49 (s), 12.35 (br), 8.21 (d), 8.14 ( d), 7.92-7.84 (m), 7.78 (d), 7.75-7.41 (m), 3.78 (s), 3.46 (s), 1.40 (9H, s)

  Next, although the specific example of the synthesis | combining method of an azo metal complex dye is shown, this invention is not limited to these methods.

[Synthesis of (A-1)]

A 50 ml eggplant flask was charged with 1.0 g of compound (L-1) and 10 ml of ethanol, and 2.07 ml of DBU was added dropwise with stirring. The mixture was stirred for 10 minutes, 780 mg of Cu (OAc) ₂ .H ₂ O was further added, and the mixture was heated to reflux for 3 hours. The temperature was returned to room temperature, and the precipitate was filtered and washed with ethanol to obtain 1.18 g of compound (A-1). The compound was identified by ESI-MS.
m / z = 1418.7 (nega), 745.0 (nega), 711.5 (posi)

[Synthesis of Compound (B-1)]

In the synthesis method of Example Compound (A-1), substituting Cu with (OAc) ₂ · H ₂ O to _{Co (OAc) 2 · 4H 2} O, to synthesize a compound (B-1) by reacting in the same manner. The compound was identified by MALDI-MS.
m / z = 818 (nega), 102 (posi)

[Synthesis of Compound (B-2)]

In the synthesis method of Example Compound (A-1), substituting Cu with (OAc) ₂ · H ₂ O to _{Ni (OAc) 2 · 4H 2} O, to synthesize a compound (B-2) by reaction in the same manner. The compound was identified by MALDI-MS.
m / z = 818 (nega), 102 (posi)

  (A-2) to (A-8), (A-12), and (A-13) were synthesized by a method similar to the method for synthesizing the compound (A-1) described above.

  (B-4), (B-7), (B-9), and (B-11) were synthesized by the same method as the synthesis method of the compound (B-1) described above.

<< Production of optical information recording medium >>
An optical information recording medium having the layer structure shown in FIG. 1 was produced by the following method.
(Production of substrate)
Thickness 1.1 mm, outer diameter 120 mm, inner diameter 15 mm, spiral pre-groove (track pitch: 320 nm, groove width: groove (recess) width 190 nm, groove depth: 47 nm, groove inclination angle: 65 °, wobble amplitude: An injection molded substrate made of polycarbonate resin having a thickness of 20 nm) was produced. Mastering of the stamper used at the time of injection molding was performed using laser cutting (351 nm).

(Formation of light reflection layer)
An ANC light reflecting layer (Ag: 98.1 at%, Nd: 0.7 at%, as a vacuum film-forming layer having a film thickness of 60 nm was formed on the substrate by DC sputtering in an Ar atmosphere using Cube manufactured by Unaxis. Cu: 0.9 at%) was formed. The film thickness of the light reflecting layer was adjusted by the sputtering time.

(Formation of write-once recording layer)
As Examples 1 to 10, 1 g of each of compounds (A-1) to (A-8), (B-1) and (B-2) was added to 100 ml of 2,2,3,3-tetrafluoropropanol. And dissolved to prepare a pigment-containing coating solution. Then, the prepared dye-containing coating liquid is applied on the first light reflecting layer 18 by changing the rotational speed from 500 to 2200 rpm by a spin coating method under the conditions of 23 ° C. and 50% RH. Layer 14 was formed.

  After the write-once recording layer was formed, annealing treatment was performed in a clean oven. The annealing treatment was performed by supporting the substrate on a vertical stack pole while leaving a gap with a spacer, and holding at 80 ° C. for 1 hour.

(Formation of barrier layer)
Thereafter, a barrier layer having a thickness of 10 nm made of Nb ₂ O ₅ was formed by DC sputtering in an Ar atmosphere on the write-once recording layer using Cube manufactured by Unaxis.

(Covering the cover layer)
As the cover layer, a polycarbonate film (Teijin Pure Ace, thickness: 80 μm) having an inner diameter of 15 mm and an outer diameter of 120 mm and having an adhesive layer (glass transition temperature of −52 ° C.) on one side, the adhesive layer and the polycarbonate film are used. The total thickness was set to 100 μm.
Then, after the cover layer was placed on the barrier layer via the adhesive layer, the cover layer was pressed and pressed with a pressing member. Through the above steps, an optical information recording medium having the layer structure shown in FIG. 1 was produced.

  Thereby, optical information recording media according to Examples 1 to 10 were produced.

<Dye layer thickness measurement>
A cross-sectional view of the obtained optical information recording medium was observed with an SEM, and the film thicknesses of the groove concave portion and convex portion of the dye layer were read. The groove concave portion of the dye layer had a groove depth of +0 to 10 nm, and the groove convex portion of the dye layer was about 10 to 30 nm.

Comparative Examples 1 to 6: Production of Optical Information Recording Medium Comparison was made in the same manner except that Comparative Compounds (A) to (F) were used in place of Illustrative Compound (A-1) as the dye used in the write-once recording layer. Optical information recording media of Examples 1 to 6 were produced.

<Evaluation of optical information recording media>
(1) Jitter evaluation The produced optical information recording medium was irradiated with light from the cover layer side using a recording / reproduction evaluation machine (Pulstec Industrial Co., Ltd .: DDU1000) having a 405 nm laser and NA 0.85 pickup, and the clock frequency A mark length modulation signal (17PP) subjected to (1.7) RLL-NRZI modulation was recorded at 66 MHz and a linear velocity of 4.92 m / s. Jitter measurement was performed using a time interval analyzer (Yokogawa Electric Corporation: TA520) by passing the recording signal through a limit equalizer.

(2) Light Resistance Evaluation of Dye Films Dye-containing coating solutions similar to those in Examples 1 to 10 and Comparative Examples 1 to 6 were prepared, and the prepared pigment-containing coating solution on a glass plate having a thickness of 1.1 mm, It was applied under the conditions of 23 ° C. and 50% RH while changing the rotational speed from 500 to 1000 rpm by a spin coating method. Then, after storing for 24 hours at 23 ° C. and 50% RH, a light resistance test was conducted using a merry-go-round type light resistance tester (manufactured by Eagle Engineering Co., Ltd., cell test machine type III, with WG320 filter manufactured by Schott). With respect to the dye film immediately before the light resistance test and the dye film after 48 hours of the light resistance test, the absorption spectrum of the dye film was measured using UV-1600PC (manufactured by SHIMADZU), and the change in absorbance at the maximum absorption wavelength was read.

(3) Storage Stability Evaluation of Dye Solution For each of Examples 1 to 10 and Comparative Examples 1 to 6, the prepared dye-containing coating solution was stored at 25 ° C. for 168 hours, and then the optical information recording medium in the same manner as described above. Was made. The recording characteristics of each optical information recording medium were similarly evaluated.

  (Note 1) When the dye residual ratio at absorption λmax after irradiation with Xe light is 90% or more, ◎, when 80% or more and less than 90%, ○, when 70% or more and less than 80%, or when less than 70% X.

  (Note 2) ◎ when the jitter value is less than 7%, ◯ when it is 7% or more and less than 8%, and × when it is 8% or more.

  (Note 3) Since the solubility was poor and the recording layer could not be formed sufficiently, measurement or recording could not be performed.

  As shown in Table 6, compared with Comparative Examples 1 to 6 using conventional azo metal complexes, in Examples 1 to 10, both the light resistance and the recording / reproduction characteristics can be achieved. As a good property.

  In addition, the azo metal complex dye used in the examples exhibited good solubility in the coating solvent and good film stability.

  Further, when the comparative compounds (A) to (D) and (F) were stored in a coating solvent (25 ° C.), the absorption spectrum changed greatly and the stability of the compound was poor, whereas the exemplary compounds (A-1) ), (A-4), (A-7), and (A-8) were found to have almost no change in absorption spectrum under the same conditions and excellent stability.

  Since light resistance is an important performance required for dyes in various applications, the azo metal complex dyes used in the examples with excellent light resistance are inks, color filters, color conversion filters, photographic materials, thermal transfer recording materials, etc. Have been found to exhibit favorable performance in various applications.

  Furthermore, it was also found that the azo metal complex dyes used in Examples 1 to 10 did not decompose or melt even when placed in a powder state and a film state at a temperature of 150 ° C., and were excellent in thermal stability. A pigment having excellent thermal stability can exhibit favorable performance in various applications such as inks, color filters, color conversion filters, and photographic materials.

  In addition, the optical information recording medium and the azo metal complex dye according to the present invention are not limited to the above-described embodiments, and can of course have various configurations without departing from the gist of the present invention.

By using the azo metal complex dye of the present invention as a dye for a recording layer, an optical information recording medium exhibiting excellent recording / reproduction characteristics and extremely high light resistance (particularly information by irradiation with laser light having a wavelength of 440 nm or less). Can be manufactured).
The azo metal complex dye of the present invention can also be applied to photographic materials, color filter dyes, color conversion filters, thermal transfer recording materials, inks, and the like.

It is a schematic sectional drawing which shows an example of the optical information recording medium of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10A ... 1st optical information recording medium 12 ... 1st board | substrate 14 ... 1st write-once recording layer 16 ... cover layer 18 ... 1st light reflection layer 20 ... barrier layer 22 ... 1st intermediate | middle layer 44 ... hard-coat layer

Claims (11)

An optical information recording medium having a recording layer on the surface of a substrate having a pregroove with a track pitch of 50 to 500 nm on the surface,
The recording layer contains an azo metal complex dye, which is a complex of an azo dye and a metal ion represented by the following general formula (1).

[In General Formula (1), Q ¹ represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms, G ¹ represents a heterocycle or a carbocycle, and E ¹ represents an electron withdrawing group. Represents. ] The optical information recording medium according to claim ¹ , wherein G ¹ in the general formula (1) represents the following partial structure.

[In the above, * represents the bonding position to the —N═N— group, and Q ² represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. ] The optical information recording medium according to claim ¹ , wherein G ¹ in the general formula (1) represents a pyrazole ring, a thiadiazole ring, or an isoxazole ring. In general formula (1), the nitrogen-containing heterocycle formed by the carbon atom adjacent to Q ¹ and the nitrogen atom is a pyridine ring, thiazole ring, oxazole ring, imidazole ring, the following partial structure (C-1) or (C -2) The optical information recording medium according to any one of claims 1 to 3, which represents any one of the above.

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ] The light according to claim 1, wherein the azo metal complex dye is an azo metal complex dye that is a complex of an azo dye represented by the following general formula (3) and a copper ion, a nickel ion, a cobalt ion, or an iron ion. Information recording medium.

[In General Formula (3), E ² represents a cyano group or an alkoxycarbonyl group, and Q ³ together with the adjacent carbon atom and nitrogen atom, a pyridine ring, an oxazole ring, a thiazole ring, the following partial structure (C-1) or ( C-2) represents an atomic group that forms any one of the above, and Q ⁴ represents an atomic group that forms a nitrogen-containing heterocycle with adjacent carbon atoms and nitrogen atoms. ]

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ] The optical information recording medium according to claim 5, wherein the ring structure formed together with the carbon atom and the nitrogen atom adjacent to Q ⁴ in the general formula (3) is represented by the following partial structure.

[In the above, * represents a bonding position with —N═N— group, and R ^{7 to} R ⁹ each independently represents a hydrogen atom or a substituent. ] The azo metal complex dye includes an azo metal complex dye that is a complex of the azo dye represented by the general formula (1) and a transition metal ion equal to or more than the number of the azo dye. The metal complex dye contains two or more transition metal ions in one molecule, provided that a plurality of transition metal ions contained in one molecule of the azo metal complex dye may be the same or different from each other. The optical information recording medium according to any one of claims 1 to 6, wherein when a plurality of azo dyes are contained in one molecule of the complex dye, the plurality of azo dyes may be the same or different from each other. The optical information recording medium according to claim 1, which is used for recording information by irradiating a laser beam having a wavelength of 440 nm or less. 9. The optical information recording medium according to claim 8, further comprising a reflective layer between the substrate and the recording layer, wherein the recording layer is irradiated with the laser light from a surface opposite to the surface facing the reflective layer. An information recording method for recording information on a recording layer of the optical information recording medium by irradiating the optical information recording medium according to any one of claims 1 to 9 with a laser beam having a wavelength of 440 nm or less. An azo dye which is a complex of an azo dye represented by the following general formula (5) and a copper ion of the same number or more than the number of the azo dye, and contains two or more copper ions in one molecule Metal complex dye.

[In General Formula (5), E ² represents a cyano group or an alkoxycarbonyl group, Q ³ together with the adjacent carbon atom and nitrogen atom, a pyridine ring, an oxazole ring, a thiazole ring, the following partial structure (C-1) or ( represents an atomic group forming one of the C-2), R ⁷ and R ⁸ each independently represent a hydrogen atom or a substituent. ]

[In the above, R ^{1 to} R ⁶ each independently represent a hydrogen atom or a substituent, and * represents a bonding position with a carbon atom. ]

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