JP5133105B2 - Optical information recording medium, information recording method, and azo metal complex dye - Google Patents

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.

  Conventionally, a write-once CD (CD-R) and a write-once DVD (DVD-R) are known as optical information recording media capable of recording information only once with a laser beam. Information recording on a CD-R is performed by a near-infrared laser beam (usually a wavelength of about 780 nm), whereas information recording on a DVD-R is performed by a visible laser beam (about 630 to 680 nm). Is called. Since DVD-R uses laser light having a shorter wavelength than CD-R as recording laser light, DVD-R has an advantage that high-density recording is possible compared to CD-R. Therefore, in recent years, DVD-R has secured its position as a large-capacity recording medium to some extent.

  Recently, networks such as the Internet and high-definition TV are rapidly spreading. In addition, there is an increasing demand for a large-capacity recording medium for recording image information inexpensively and easily, with the upcoming broadcast of HDTV (High Definition Television). 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 an optical disk, for example, an optical recording disk (Blu-ray Disc, hereinafter also referred to as “BD”) using a blue laser of 405 nm, an information recording laser beam such as an HD-DVD. It has been proposed to increase the recording density by shortening the wavelength.

  For example, Patent Documents 1 to 4 propose using an azo metal complex dye as a dye compound contained in a recording layer in a DVD-R type optical disk. These azo metal complex dyes have an absorption waveform corresponding to a red laser, and recording with a laser beam having a short wavelength (for example, 405 nm) cannot exhibit sufficient recording characteristics.

Therefore, in an optical recording disk using a short wavelength laser beam (for example, a 405 nm blue laser beam), it has been studied to shorten the absorption wavelength of the azo metal complex used in the DVD-R. (Patent Documents 5-7 etc.)
JP-A-11-310728 JP-A-11-130970 JP 2002-274040 A JP 2000-168237 A JP 2001-158862 A JP 2006-142789 A JP 2006-306070 A

  However, the present inventors 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 5 to 7 above. As a result, it was not possible to find one satisfying all of light resistance and recording / reproduction characteristics (jitter, reproduction durability).

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

The inventors have studied the light resistance of the dye and the recording / reproducing characteristics of the blue laser compatible optical information recording medium, and as a result, have obtained the following knowledge.
The azo metal complex dyes specifically disclosed in Patent Documents 5 to 7 are all azo metal complex dyes in which two azo dyes are coordinated to one metal ion. However, with these metal complexes, sufficient light resistance and recording / reproducing characteristics could not be obtained by recording / reproducing by irradiation with the short wavelength laser beam.
Therefore, the present inventors have studied, and firstly obtained knowledge that an azo metal complex dye containing a transition metal ion is superior among azo metal complex dyes from the viewpoint of recording and reproducing characteristics in a short wavelength region. . However, even with an azo metal complex dye containing a transition metal ion, the azo metal complex dyes described in Patent Documents 5 to 7 have not been able to find one having both light resistance and recording / reproduction characteristics. Furthermore, it was not possible to find a dye having good reproduction durability from the azo metal complex dyes.
Based on the above knowledge, the present inventor considered that the reason why the azo metal complex dye cannot satisfy the light resistance or the reproduction durability is that the excited state of the azo ligand cannot be deactivated efficiently. . Therefore, the present inventors increase the number of transition metal ions in the azo metal complex dye to the same number or more as the number of azo dyes, and increase the number of transition metal ions coordinated with one azo dye. By increasing the number, the energy transfer from the azo ligand to the metal ion can be promoted. As a result, an optical information recording medium excellent in light resistance, reproduction durability against short-wavelength laser irradiation, and recording / reproduction characteristics can be obtained. I found out that
Furthermore, specific azo metal complex dyes having a copper ion and azo ligand number of 2 to 2, or 5 to 4 are used as recording layer dyes in optical information recording media for short wavelength lasers such as Blu-ray discs. As a result, it has been newly found out that good recording / reproduction characteristics can be obtained, and that the dye is excellent in light resistance, solubility, and stability of the dye film formed.
The present invention has been completed based on the above findings.

[一般式（Ａ）中、Ｒ¹およびＲ²は、各々独立に、水素原子または置換基を表し、Ｙ¹は記録層中で解離していてもよい水素原子を表し、＊は−Ｎ＝Ｎ−基との結合位置を表す。]
[５]前記アゾ色素は、下記一般式（１）で表されるアゾ色素である[４]に記載の光情報記録媒体。

［一般式（１）中、Ｑ¹は複素環または炭素環を形成する原子群を表し、Ｙは記録層中で解離していてもよい水素原子を含有する基を表し、Ｒ¹、Ｒ²およびＹ¹は、それぞれ一般式（Ａ）における定義と同義である。］
[６]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遷移金属イオンとを塩基存在下で反応させることにより得られたものである[５]に記載の光情報記録媒体。
[７]前記記録層は、塩基を含む[１]〜[６]のいずれかに記載の光情報記録媒体。
[８]一般式（１）中の下記部分構造：

は、下記部分構造式（Ｅ−１）〜（Ｅ−６）、または（Ｅ−８）のいずれかを表す[５]〜[７]のいずれかに記載の光情報記録媒体。

[上記において、Ｒ⁴¹〜Ｒ⁵⁶、Ｒ⁵⁹〜Ｒ⁶²は、各々独立に水素原子または置換基を表し、隣接する置換基は互いに連結して環を形成してもよい。但し、Ｒ⁴⁶〜Ｒ⁴⁹が置換基を表す場合、該置換基はアミノ基、ヒドロキシル基、アルコキシ基およびアリールオキシ基以外の置換基である。]
[９]前記遷移金属イオンは銅イオンである[１]〜[８]のいずれかに記載の光情報記録媒体。
[１０]前記Ｒ¹は、炭素数２〜１０の置換もしくは無置換のアルキルオキシカルボニル基、またはシアノ基である[４]〜[９]のいずれかに記載の光情報記録媒体。
[１１]前記アゾ金属錯体色素は、下記一般式（Ｆ）または一般式（Ｈ）で表されるアゾ金属錯体色素である[１]〜[１０]のいずれかに記載の光情報記録媒体。

［一般式（Ｆ）中、Ｌ^2-は下記一般式（２）で表されるアゾ色素から水素原子２つが解離した２価アニオンを表し、Ｇは電荷を中和するために必要なイオンを表し、ｖは０〜２の範囲の整数を表し、Ｌ’は配位子を表し、ｘは０〜６の範囲の整数を表す。］

［一般式（２）中、Ｙ¹¹は上記２つの水素原子のうちの一方の水素原子を含有する基を表し、Ｙ¹²は上記２つの水素原子のうちの他方の水素原子を表し、Ｒ¹¹は、炭素数２〜１０の置換もしくは無置換のアルキルオキシカルボニル基またはシアノ基を表し、Ｒ¹²は水素原子または置換基を表し、下記部分構造：

は、下記部分構造式（Ｅ−１）〜（Ｅ−６）、または（Ｅ−８）のいずれかを表す。］

[上記において、Ｒ⁴¹〜Ｒ⁵⁶、Ｒ⁵⁹〜Ｒ⁶²は、各々独立に水素原子または置換基を表し、隣接する置換基は互いに連結して環を形成してもよい。但し、Ｒ⁴⁶〜Ｒ⁴⁹が置換基を表す場合、該置換基はアミノ基、ヒドロキシル基、アルコキシ基およびアリールオキシ基以外の置換基である。]

［一般式（Ｈ）中、Ｚ¹¹は、下記部分構造：

中のＹ¹¹から水素原子が１つ解離した基を表し、上記部分構造、Ｒ¹¹およびＲ¹²は、それぞれ一般式（Ｆ）における定義と同義であり、一般式（Ｈ）中にそれぞれ２つ存在するＱ¹¹、Ｚ¹¹、Ｒ¹¹およびＲ¹²は互いに同一でも異なっていてもよく、Ｌ¹¹およびＬ¹²は、それぞれ独立に配位子を表し、ｎ¹¹およびｎ¹²は、それぞれ独立に０〜２の範囲の整数を表す。Ｌ¹¹、Ｌ¹²が複数存在する場合、複数存在するＬ¹¹、Ｌ¹²は互いに同じであっても異なっていてもよい。］
[１２]波長４４０ｎｍ以下のレーザー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]〜[１１]のいずれかに記載の光情報記録媒体。
[１３]前記基板と前記記録層との間に反射層を有し、前記レーザー光は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される[１２]に記載の光情報記録媒体。
[１４][１]〜[１３]のいずれかに記載の光情報記録媒体に、波長４４０ｎｍ以下のレーザー光を照射することにより前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。
[１５]下記一般式（Ｆ）または一般式（Ｈ）で表されるアゾ金属錯体色素。

［一般式（Ｆ）中、Ｌ^2-は下記一般式（２）で表されるアゾ色素から水素原子２つが解離した２価のアニオンを表し、Ｇは電荷を中和するために必要なイオンを表し、ｖは０〜２の範囲の整数を表し、Ｌ’は配位子を表し、ｘは０〜６の範囲の整数を表す。］

［一般式（２）中、Ｙ¹¹は上記２つの水素原子のうちの一方の水素原子を含有する基を表し、Ｙ¹²は上記２つの水素原子のうちの他方の水素原子を表し、Ｒ¹¹は、炭素数２〜１０の置換もしくは無置換のアルキルオキシカルボニル基またはシアノ基を表し、Ｒ¹²は水素原子または置換基を表し、下記部分構造：

は、下記部分構造式（Ｅ−１）〜（Ｅ−６）、または（Ｅ−８）のいずれかを表す。］

[上記において、Ｒ⁴¹〜Ｒ⁵⁶、Ｒ⁵⁹〜Ｒ⁶²は、各々独立に水素原子または置換基を表し、隣接する置換基は互いに連結して環を形成してもよい。但し、Ｒ⁴⁶〜Ｒ⁴⁹が置換基を表す場合、該置換基はアミノ基、ヒドロキシル基、アルコキシ基およびアリールオキシ基以外の置換基である。]

［一般式（Ｈ）中、Ｚ¹¹は、下記部分構造：

中のＹ¹¹から水素原子が１つ解離した基を表し、上記部分構造、Ｒ¹¹およびＲ¹²は、それぞれ一般式（Ｆ）における定義と同義であり、一般式（Ｈ）中にそれぞれ２つ存在するＱ¹¹、Ｚ¹¹、Ｒ¹¹およびＲ¹²は互いに同一でも異なっていてもよく、Ｌ¹¹およびＬ¹²は、それぞれ独立に配位子を表し、ｎ¹¹およびｎ¹²は、それぞれ独立に０〜２の範囲の整数を表す。Ｌ¹¹、Ｌ¹²が複数存在する場合、複数存在するＬ¹¹、Ｌ¹²は互いに同じであっても異なっていてもよい。］ 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 includes an azo metal complex dye that is a complex of an azo dye and a transition metal ion equal to or more than the number of the azo dyes, and two or more of the azo metal complex dyes per molecule. Wherein a plurality of transition metal ions contained in one molecule of the azo metal complex dye may be the same or different, and a plurality of azo dyes may be contained in one molecule of the azo metal complex dye. When included, the plurality of azo dyes may be the same or different, respectively.
[2] The azo metal complex dye contains two azo dyes and two transition metal ions in one molecule by at least one analysis selected from the group consisting of ESI-MS, MALDI-MS, and X-ray structural analysis. The optical information recording medium according to [1], which shows a result of inclusion.
[3] The azo metal complex dye contains four azo dyes and five transition metal ions in one molecule by at least one analysis selected from the group consisting of ESI-MS, MALDI-MS, and X-ray structural analysis. The optical information recording medium according to [1], which shows a result of inclusion.
[4] The optical information recording medium according to any one of [1] to [3], wherein the azo dye is an azo dye having a partial structure represented by the following general formula (A).

[In General Formula (A), R ¹ and R ² each independently represent a hydrogen atom or a substituent, Y ¹ represents a hydrogen atom that may be dissociated in the recording layer, and * represents —N═ This represents the bonding position with the N-group. ]
[5] The optical information recording medium according to [4], wherein the azo dye is an azo dye represented by the following general formula (1).

[In General Formula (1), Q ¹ represents an atomic group forming a heterocyclic ring or a carbocyclic ring, Y represents a group containing a hydrogen atom which may be dissociated in the recording layer, and R ¹ , R ² And Y ¹ have the same definitions as in general formula (A). ]
[6] The optical information recording according to [5], wherein the azo metal complex dye is obtained by reacting the azo dye represented by the general formula (1) with a transition metal ion in the presence of a base. Medium.
[7] The optical information recording medium according to any one of [1] to [6], wherein the recording layer contains a base.
[8] The following partial structure in the general formula (1):

Is the optical information recording medium according to any one of [5] to [7], which represents any one of the following partial structural formulas (E-1) to (E-6) or (E-8).

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]
[9] The optical information recording medium according to any one of [1] to [8], wherein the transition metal ion is a copper ion.
[10] The optical information recording medium according to any one of [4] to [9], wherein R ¹ is a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms or a cyano group.
[11] The optical information recording medium according to any one of [1] to [10], wherein the azo metal complex dye is an azo metal complex dye represented by the following general formula (F) or general formula (H).

[In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from the azo dye represented by the following general formula (2), and G represents an ion necessary for neutralizing the charge. V represents an integer in the range of 0 to 2, L ′ represents a ligand, and x represents an integer in the range of 0 to 6. ]

[In General Formula (2), Y ¹¹ represents a group containing one of the two hydrogen atoms, Y ¹² represents the other hydrogen atom of the two hydrogen atoms, R ¹¹ Represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, R ¹² represents a hydrogen atom or a substituent, and has the following partial structure:

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8). ]

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]

[In General Formula (H), Z ¹¹ represents the following partial structure:

Represents a group in which one hydrogen atom is dissociated from Y ¹¹ therein, and the partial structures, R ¹¹ and R ¹² , have the same definitions as in general formula (F), and two each in general formula (H). Q ¹¹ , Z ¹¹ , R ¹¹ and R ^{12 present} may be the same or different from each other, L ¹¹ and L ¹² each independently represent a ligand, and n ¹¹ and n ¹² are each independently 0 Represents an integer in the range of ~ 2. When a plurality of L ¹¹ and L ¹² are present, the plurality of L ¹¹ and L ¹² may be the same as or different from each other. ]
[12] The optical information recording medium according to any one of [1] to [11], which is used for recording information by irradiating a laser beam having a wavelength of 440 nm or less.
[13] The light according to [12], further including a reflective layer between the substrate and the recording layer, wherein the laser light is irradiated to the recording layer from a surface opposite to the surface facing the reflective layer. Information recording medium.
[14] 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 [1] to [13] with a laser beam having a wavelength of 440 nm or less. .
[15] An azo metal complex dye represented by the following general formula (F) or general formula (H).

[In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from the azo dye represented by the following general formula (2), and G represents an ion necessary for neutralizing the charge. , V represents an integer in the range of 0 to 2, L ′ represents a ligand, and x represents an integer in the range of 0 to 6. ]

[In General Formula (2), Y ¹¹ represents a group containing one of the two hydrogen atoms, Y ¹² represents the other hydrogen atom of the two hydrogen atoms, R ¹¹ Represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, R ¹² represents a hydrogen atom or a substituent, and has the following partial structure:

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8). ]

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]

[In General Formula (H), Z ¹¹ represents the following partial structure:

Represents a group in which one hydrogen atom is dissociated from Y ¹¹ therein, and the partial structures, R ¹¹ and R ¹² , have the same definitions as in general formula (F), and two each in general formula (H). Q ¹¹ , Z ¹¹ , R ¹¹ and R ^{12 present} may be the same or different from each other, L ¹¹ and L ¹² each independently represent a ligand, and n ¹¹ and n ¹² are each independently 0 Represents an integer in the range of ~ 2. When a plurality of L ¹¹ and L ¹² are present, the plurality of L ¹¹ and L ¹² may be the same as or different from each other. ]

According to the present invention, an optical information recording medium having excellent recording / reproduction characteristics and excellent light resistance using blue laser light having a wavelength of 440 nm or less (particularly information by irradiation with laser light having a wavelength of 440 nm or less). Can be obtained.
The azo metal complex dye of the present invention is suitable for various applications since it exhibits excellent light resistance, and is particularly suitable as an optical information recording material because of its good film stability.

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

The optical information recording medium of the present invention has a recording layer directly or via a layer such as a reflective layer on the surface of a substrate having a pregroove with a track pitch of 50 to 500 nm on the surface. The optical information recording medium of the present invention is suitable as an optical disc for high-density recording in which information is recorded by a short wavelength laser such as BD or 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. Also, an optical disc having a BD structure has a reflective layer and a recording layer in this order on a substrate, and further has a relatively thin light-transmitting layer (generally called a cover layer) on the recording layer. This has a different layer structure from the write-once optical disc. In such an optical information recording medium compatible with a short wavelength laser, sufficient recording / reproducing characteristics cannot be obtained with a dye used as a recording dye for a conventional write-once optical information recording medium such as CD-R or DVD-R. The point was a challenge.
In contrast, in the present invention, in an optical information recording medium having a narrow track pitch as compared with a conventional write-once optical information recording medium, an azo dye and transition metal ions of the same number or more than the number of the azo dye The recording layer contains an azo metal complex dye containing two or more transition metal ions in one molecule, which makes it possible to obtain good recording / reproduction characteristics. . According to the optical information recording medium of the present invention, it is possible to obtain good recording / reproduction characteristics by irradiation with laser light having a short wavelength (for example, a wavelength of 440 nm or less), and furthermore, extremely good light resistance and good wet heat storage property. Can be obtained. In particular, the optical information recording medium of the present invention has a reflective layer between the substrate and the recording layer, and the laser beam used for recording and reproduction is from the surface opposite to the surface facing the reflective layer to the recording layer. It is suitable as a medium having a BD structure to be irradiated.
Furthermore, it was newly found that the azo metal complex dye of the present invention represented by the general formula (F) or (H) exhibits extremely good light resistance, good solubility, and excellent film stability. . Thus, according to the present invention, it is possible to provide an optical information recording medium having excellent recording characteristics by irradiation with a short wavelength laser beam, high light resistance, and excellent solubility and film stability.
In the present invention, an azo dye represents a dye compound having an azo structure and capable of forming a complex with a metal ion, and includes a case where it is a ligand in a metal complex. For example, when two azo ligands are coordinated to one metal ion in one molecule, the number of azo dyes in one molecule is two. A case where an azo dye is complexed with a metal ion is called an azo metal complex. In the present invention, the azo ligand refers to a case where an azo dye becomes a ligand. The azo ligand preferably becomes an anionic ligand by losing a dissociative hydrogen atom, and becomes a divalent anionic ligand by losing two dissociative hydrogen atoms.
In the present invention, the transition metal ion represents an ion of a transition metal atom. The 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, Cu and Zn are more preferable, Cu is still more preferable.

The transition metal ion is preferably a monovalent or divalent transition metal ion. Examples of monovalent or divalent transition metal ions include Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ⁺ , Cu ²⁺ , Zn ²⁺ , Ru ²⁺ , Pd ²⁺ , and Ag. ⁺ , Re ⁺ , Pt ²⁺ , Au ^{+ and the} like, preferably including a transition metal ion having a stable coordination number of 4 such as Cu ²⁺ , Zn ²⁺ , Pd ²⁺ , Pt ²⁺ , Cu ²⁺ is more preferred.

  The recording layer of the optical information recording medium of the present invention will be described below.

  The recording layer of the optical information recording medium of the present invention is a complex of an azo dye (including an azo ligand) and a transition metal ion having the same number or more than the number of the azo dye. An azo metal complex dye containing two or more transition metal ions is contained in the recording layer. 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. The light resistance of the recording layer can be improved by increasing the number of transition metal ions in the azo metal complex dye to be the same as or more than that of the azo dye. Furthermore, the light stability and thermal stability before and after recording and the reproduction durability can also be improved. The azo metal complex dye is a complex containing azo dyes and transition metal ions of the same number or more as the number of azo dyes as constituent components, and two or more transition metal ions in one molecule. It may be a complex to be contained, and may contain other components such as ions necessary for neutralizing the charge of the ligand or molecule, together with the azo dye and the transition metal ion. However, the azo dye is excluded from the case of an azo dye having the following partial structures (1-1) and (1-2).

[上記において、Ｒ⁶、Ｒ⁷およびＲ⁸は、それぞれ独立に水素原子または置換基を表し、＊は、−Ｎ＝Ｎ−基との結合位置を表す。]

[In the above, R ⁶ , R ⁷ and R ⁸ each independently represents a hydrogen atom or a substituent, and * represents a bonding position to the —N═N— group. ]

  At least a part of the azo dye contained in the azo metal complex dye is preferably a divalent azo dye anion. This is because the effective deactivation of the excited state of the azo ligand leads to an improvement in light resistance. Therefore, to improve energy transfer efficiency, the σ donating property is increased, and the ligand field splitting of the metal ion is increased. This is because it is considered desirable to do so (see Kodansha Scientific, New Complex Chemistry, Fundamental Complex Engineering Study Group / edition, pages 30-42).

The azo metal complex dye preferably contains two or more transition metal ions in one molecule, and at least one transition metal is preferably coordinated to one azo dye. Furthermore, it is more preferable that the azo dye becomes a bridging ligand so that two or more transition metal ions are coordinated with one azo ligand in order to improve film stability. An azo metal complex dye containing four azo dyes and five transition metal ions in one molecule, or an azo metal complex dye containing two azo dyes and two transition metal ions is preferable. As a preferred embodiment of such an azo metal complex dye, an azo metal complex dye having a partial structure represented by the general formula (A) can be mentioned, and a more preferred embodiment is represented by the general formula (1). An azo metal complex composed of an azo dye and a transition metal ion can be mentioned, and a more preferable embodiment is composed of an azo dye represented by the general formula (1) and a transition metal ion, and the general formula (F) or An azo metal complex dye having a coordination structure similar to that of the azo metal complex dye represented by the general formula (H) can be given, and a particularly preferable embodiment is represented by the general formula (F) or the general formula (H). And azo metal complex dyes. In the azo metal complex dye containing a plurality of azo dyes and a plurality of transition metal ions in one molecule as described above, the plurality of azo dyes may be the same or different, and the plurality of transition metal ions may be the same or different. It may be. The plurality of azo dyes and the plurality of transition metal ions are preferably the same.
The details of each of the azo metal complexes will be described below.

  As the azo dye, an azo dye having a partial structure represented by the following general formula (A) capable of forming a divalent azo dye anion is preferable.

[一般式（Ａ）中、Ｒ¹およびＲ²は、各々独立に、水素原子または置換基を表し、Ｙ¹は記録層中で解離していてもよい水素原子を表し、＊は−Ｎ＝Ｎ−基との結合位置を表す。]

[In General Formula (A), R ¹ and R ² each independently represent a hydrogen atom or a substituent, Y ¹ represents a hydrogen atom that may be dissociated in the recording layer, and * represents —N═ This represents the bonding position with the N-group. ]

In general formula (A), Y ¹ represents a hydrogen atom that may be dissociated in the recording layer. In the partial structure represented by the general formula (A), the hydrogen atom Y ¹ on the pyrazole ring is dissociated to form a transition metal ion with the transition metal ion via the other nitrogen atom on the pyrazole ring in the partial structure (A). Complex formation is possible, and even when the number of transition metal ions is larger than the number of azo dyes, the film stability is high and good recording characteristics can be obtained.

In general formula (A), R ¹ and R ² each independently represents a hydrogen atom or a substituent. R ¹ and R ² are preferably substituents from the viewpoint of improving solubility. Although it does not specifically limit as a substituent, A halogen atom, 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, Cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy, amino group (anilino group) ), Acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, mercapto group, alkylthio group, aryl O group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, aryl and heterocyclic azo group, imido group Examples include phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, and silyl group.
More specifically, R ¹ and R ² represent a halogen atom (for example, a chlorine atom, a bromine atom, an iodine atom), an alkyl group [a linear, branched, cyclic substituted or unsubstituted alkyl group. 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 a ring structure There tricyclo structure is intended to encompass such. 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, for example, 2-cyclopenten-1-yl, 2-cyclohexene- 1-yl), bicycloalkenyl group (substituted or unsubstituted bicycloalkenyl group, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, that is, one hydrogen atom of a bicycloalkene having one double bond. Monovalent groups removed, such as 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). An aryl group such as a phenyl group, a p-tolyl group, a naphthyl group, an m-chlorophenyl group, an o-hexadecanoylaminophenyl group), a heterocyclic group (preferably a 5- or 6-membered substituted or unsubstituted aromatic or It is a monovalent group obtained by removing one hydrogen atom from a non-aromatic heterocyclic compound, and more preferably a 5- to 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms. Furyl group, 2-thienyl group, 2-pyrimidinyl group, 2-benzothiazolyl group), cyano group, hydroxyl group, nitro group, carboxyl An alkoxy 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 or 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- A tetradecanoylaminophenoxy group), a silyloxy group (preferably a silyloxy group having 3 to 20 carbon atoms, such as a trimethylsilyloxy group or a t-butyldimethylsilyloxy group), a heterocyclic oxy group (preferably having a carbon number of 2 30 substituted or unsubstituted heterocyclic oxy groups, 1-phenyltetrazol-5-oxy Group, 2-tetrahydropyranyloxy group), acyloxy group (preferably formyloxy group, substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms) Group, for example, formyloxy group, acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group), carbamoyloxy group (preferably substituted or unsubstituted having 1 to 30 carbon atoms) Carbamoyloxy groups such as N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N, N-di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy Group), alkoxy A carbonyloxy 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 aryloxy Carbonyloxy 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, and dimethyl) Amino group, a Lino group, N-methyl-anilino group, diphenylamino group), acylamino group (preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms, substituted or unsubstituted group having 6 to 30 carbon atoms) Substituted arylcarbonylamino groups such as formylamino group, acetylamino group, pivaloylamino group, lauroylamino group, benzoylamino group, 3,4,5-tri-n-octyloxyphenylcarbonylamino group), aminocarbonylamino group (Preferably, a substituted or unsubstituted aminocarbonylamino group having 1 to 30 carbon atoms, such as carbamoylamino group, N, N-dimethylaminocarbonylamino group, N, N-diethylaminocarbonylamino group, morpholinocarbonylamino group) , Alkoxycarbonyl Mino group (preferably a substituted or unsubstituted alkoxycarbonylamino group having 2 to 30 carbon atoms, for example, methoxycarbonylamino group, ethoxycarbonylamino group, t-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl Rumethoxycarbonylamino group), aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms, such as phenoxycarbonylamino group, p-chlorophenoxycarbonylamino group, m- n-octyloxyphenoxycarbonylamino group), sulfamoylamino group (preferably a substituted or unsubstituted sulfamoylamino group having 0 to 30 carbon atoms, such as sulfamoylamino group, N, N-dimethylamino Sulfo Nylamino group, Nn-octylaminosulfonylamino group), alkyl and arylsulfonylamino groups (preferably substituted or unsubstituted alkylsulfonylamino groups having 1 to 30 carbon atoms, substituted or unsubstituted groups having 6 to 30 carbon atoms) Arylsulfonylamino group, for example, methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,5-trichlorophenylsulfonylamino group, p-methylphenylsulfonylamino group), mercapto group, alkylthio group (preferably Is 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, for example, Phenylti Group, p-chlorophenylthio 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 -Phenyltetrazol-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 Represents a substituted or unsubstituted alkylsulfinyl group having 1 to 30 carbon atoms, 6 to 30 carbon atoms. Or an unsubstituted arylsulfinyl group, for example, a methylsulfinyl group, an ethylsulfinyl group, a phenylsulfinyl group, a p-methylphenylsulfinyl group), an alkyl and an arylsulfonyl group (preferably a substituted or unsubstituted group having 1 to 30 carbon atoms) Alkylsulfonyl group, 6-30 substituted or unsubstituted arylsulfonyl group such as methylsulfonyl group, ethylsulfonyl group, phenylsulfonyl group, p-methylphenylsulfonyl group), acyl group (preferably formyl group, carbon number 2) A substituted or unsubstituted alkylcarbonyl group having 30 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, and a heterocyclic ring bonded to the carbonyl group at a substituted or unsubstituted carbon atom having 4 to 30 carbon atoms 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 Heterocyclic azo group (preferably a substituted or unsubstituted arylazo group having 6 to 30 carbon atoms, a substituted or unsubstituted heterocyclic azo group having 3 to 30 carbon atoms, such as phenylazo group, p-chlorophenylazo group, 5- Ethylthio-1,3,4-thiadiazol-2-ylazo group), imide group (preferably N-succinimide, N-phthalimide), phosphino group (preferably substituted or unsubstituted phosphino group having 2 to 30 carbon atoms) For example, dimethylphosphino group, diphenylphosphino group, methylphenoxyphosphine Group), a 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 a diphenoxyphosphinyloxy group or a dioctyloxyphosphinyloxy group, or a phosphinylamino group (preferably having a carbon number). 2-30 substituted or unsubstituted phosphinylamino groups such as dimethoxyphosphinylamino group and dimethylaminophosphinylamino group, silyl groups (preferably substituted or unsubstituted 3 to 30 carbon atoms) A silyl group such as trimethylsilyl, t-butyldimethylsilyl, phenyldimethylsilyl) .
Among the above functional groups, those having a hydrogen atom may be substituted with the above groups by removing this. Examples of such functional groups include an alkylcarbonylaminosulfonyl group, an arylcarbonylaminosulfonyl group, an alkylsulfonylaminocarbonyl group, and an arylsulfonylaminocarbonyl group. Examples thereof include methylsulfonylaminocarbonyl, p-methylphenylsulfonylaminocarbonyl, acetylaminosulfonyl, and benzoylaminosulfonyl groups.

When R ¹ is an electron-attracting group, an azo metal complex having extremely excellent light resistance can be easily obtained, which is preferable from the viewpoint of solubility. Preferred electron withdrawing groups as R ¹ are substituted or unsubstituted alkyloxycarbonyl groups having 2 to 10 carbon atoms, substituted or unsubstituted aryloxycarbonyl groups having 7 to 10 carbon atoms, and those having 2 to 10 carbon atoms. A substituted or unsubstituted alkylaminocarbonyl group, 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 substituted or unsubstituted group having 6 to 10 carbon atoms It is preferably a group selected from a substituted arylsulfonyl group and a cyano group, a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms, a substituted or unsubstituted alkylsulfonyl group having 1 to 10 carbon atoms, cyano And a group selected from the group consisting of a substituted or unsubstituted alkyl group having 2 to 10 carbon atoms. Aryloxycarbonyl group, further preferably a cyano group, and particularly preferably a cyano group.

R ² is preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms. From the viewpoint of recording properties, R ² is preferably a hydrogen atom, 10 substituted or unsubstituted alkyl groups are more preferable, and a hydrogen atom and a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms are more preferable. In addition, from the viewpoint of solubility, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms is particularly preferable.

  As the azo dye having a partial structure represented by the general formula (A), an azo dye represented by the following general formula (1) is preferable.

For the azo dye represented by the general formula (1), only the azoform in the azo-hydrazone tautomerism equilibrium is described, but the corresponding hydrazone form may be used, and the hydrazone form in this case is the present invention. The same component as the azoform in.
In addition, the pyrazole ring represented in the general formula (1) can also have a tautomeric structure, but that case is also included in the general formula (1).

In the general formula (1), R ¹ , R ² and Y ¹ have the same definitions as in the general formula (A), and the details thereof are as described above.

In the general formula (1), Q ¹ represents an atomic group forming a heterocyclic ring or a carbocyclic ring. If Q ¹ is a heterocyclic ring, Q ¹ is a carbon atom and hetero atoms (e.g. oxygen atom, a sulfur atom, a nitrogen atom and the like) may be a heterocyclic ring formed together with, but are not limited to, for example, part of the later Heterocycle, pyrrole ring, furan ring, thiophene ring, imidazole ring, thiazole ring, isothiazole ring, oxazole ring, isoxazole ring included in the rings represented by structural formulas (E-1) to (E-8), Examples thereof include a pyridine ring, a pyrazine ring, a pyrimidine ring, and a pyridazine ring. These rings may have a substituent and may be condensed.

As the carbocycle formed by Q ¹ , a benzene ring is preferable. The benzene ring may have a substituent or may be condensed, but from the viewpoint of recording / reproduction characteristics, the benzene ring is condensed to form a 10π-condensed ring (for example, naphthalene ring or quinoline ring). ) Or a 14π-type condensed ring (for example, anthracene, phenanthrene, phenanthroline, etc.). For the same reason, when the carbocycle is a benzene ring, the benzene ring is not substituted with an amino group, a hydroxyl group, an alkoxy group, or an aryloxy group.

The heterocycle and carbocycle preferably have a substituent from the viewpoint of improving solubility. Examples of the substituent include the groups exemplified as the substituents represented by R ¹ and R ² .

  Y represents a group containing a hydrogen atom that may be dissociated in the recording layer. The hydrogen atom is a hydrogen atom that is easily deprotonated, and is a hydrogen atom that can be dissociated when complexed with a transition metal ion.

Examples of the group represented by Y include a hydroxyl group, an amino group (preferably 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 amino Group, methylamino group, dimethylamino group, anilino group, N-methyl-anilino group, diphenylamino group), acylamino group (preferably formylamino group, substituted or unsubstituted alkylcarbonylamino group having 1 to 30 carbon atoms) A substituted or unsubstituted arylcarbonylamino group having 6 to 30 carbon atoms, such as formylamino group, acetylamino group, pivaloylamino group, lauroylamino group, benzoylamino group, 3,4,5-tri-n-octyloxy Phenylcarbonylamino group), aminocarbonylamino group (preferably having a carbon number of 1 to 0 substituted or unsubstituted aminocarbonylamino group, for example, carbamoylamino group, N, N-dimethylaminocarbonylamino group, N, N-diethylaminocarbonylamino group, morpholinocarbonylamino group), alkoxycarbonylamino group (preferably C2-C30 substituted or unsubstituted alkoxycarbonylamino group, for example, methoxycarbonylamino group, ethoxycarbonylamino group, t-butoxycarbonylamino group, n-octadecyloxycarbonylamino group, N-methyl-methoxycarbonylamino group ), An aryloxycarbonylamino group (preferably a substituted or unsubstituted aryloxycarbonylamino group having 7 to 30 carbon atoms such as phenoxycarbonylamino group, p-chlorophenoxycarbonyl) Mino 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, Nn-octylaminosulfonylamino group), alkyl and arylsulfonylamino groups (preferably a substituted or unsubstituted alkylsulfonylamino group having 1 to 30 carbon atoms, 6 to 30 carbon atoms). Substituted or unsubstituted arylsulfonylamino group, for example, methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,5-trichlorophenylsulfonylamino group, p-methylphenylsulfonylamino group) Can be mentioned.
Hydroxyl group, substituted or unsubstituted sulfamoylamino group having 0 to 10 carbon atoms, substituted or unsubstituted alkylsulfonylamino group having 1 to 10 carbon atoms, substituted or unsubstituted arylsulfonylamino group having 3 to 10 carbon atoms It is preferably a group, more preferably a substituted or unsubstituted sulfamoylamino group having 0 to 10 carbon atoms, or a substituted or unsubstituted alkylsulfonylamino group having 1 to 10 carbon atoms.

When Y is an amino group having a substituent, the substituent may be bonded to the atomic group represented by Q ¹ to form a ring. However, from the viewpoint of reproduction durability by irradiation with a short wavelength laser beam, The ring formed is preferably not the partial structure (1-1) or (1-2).

  Y is a hydroxyl group, a substituted or unsubstituted sulfamoylamino group having 0 to 4 carbon atoms, a substituted or unsubstituted alkylsulfonylamino group having 1 to 4 carbon atoms, a substituted or unsubstituted aryl having 3 to 10 carbon atoms It is preferably a sulfonylamino group, more preferably a hydroxyl group, a substituted or unsubstituted sulfamoylamino group having 0 to 4 carbon atoms, or a substituted or unsubstituted alkylsulfonylamino group having 1 to 4 carbon atoms. More preferably, it is a hydroxyl group.

の具体例としては、下記部分構造式（Ｅ−１）〜（Ｅ−８）等が挙げられる。 Further, the following partial structure in the general formula (1):

Specific examples of these include the following partial structural formulas (E-1) to (E-8).

In the above, R ⁴¹ , R ⁴³ , R ^{46 to} R ⁴⁹ , R ⁵⁰ , R ⁵¹ , R ⁵⁷ , R ⁵⁸ , R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents are They may be connected to each other to form a ring. When R ^{41 to} R ⁶² represent a substituent, the substituent is not particularly limited, and examples thereof include the substituents exemplified for R ¹ and R ² . R ^{46 to} R ⁴⁹ represent a substituent other than an amino group (including an amino group substituted with alkyl or aryl), a hydroxyl group, an alkoxy group, and an aryloxy group, or a hydrogen atom. This is to cope with recording and reproduction by irradiation with a short wavelength laser beam.

^R42 , ^R44 , ^R45 , ^R52 , ^R53 , ^R54 , ^R55 , ^R56 each independently represents a hydrogen atom or a substituent. Although it does not specifically limit as a substituent, An alkyl group (including a cycloalkyl group and a bicycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an aryl group, a heterocyclic group, a sulfamoyl group, alkyl and aryl Examples include sulfinyl groups, alkyl and arylsulfonyl groups, acyl groups, aryloxycarbonyl groups, alkoxycarbonyl groups, and carbamoyl groups.

  Among the partial structures, (E-1) to (E-6) and (E-8) are preferable, (E-1) to (E-3) and (E-8) are more preferable, and (E-1) ), (E-3) and (E-8) are more preferred, and (E-1) and (E-3) are particularly preferred.

In (E-1), R ⁴¹ represents an alkyl group (including a cycloalkyl group and a bicycloalkyl group), an aryl group, a heterocyclic group, a cyano group, an alkoxy group, an aryloxy group, a heterocyclic oxy group, and an aryloxycarbonyl. Group, an alkoxycarbonyl group are preferable, an alkyl group, a cyano group, an alkoxy group, an aryloxy group, and a heterocyclic oxy group are more preferable, and an alkyl group and an alkoxy group are further preferable.
R ⁴² is preferably an alkyl group (including a cycloalkyl group or a bicycloalkyl group), an aryl group or a heterocyclic group, preferably an alkyl group or an aryl group, and more preferably an aryl group.

In (E-3), R ^{46 to} R ⁴⁹ are alkyl groups (including cycloalkyl groups and bicycloalkyl groups), aryl groups, heterocyclic groups, alkoxy groups, aryloxy groups, heterocyclic oxy groups, aryloxycarbonyls. Group, an alkoxycarbonyl group are preferable, an alkyl group, an aryloxycarbonyl group, and an alkoxycarbonyl group are more preferable, and an alkoxycarbonyl group is more preferable.

  Specific examples of the azo dye represented by the general formula (1) are given below, but the present invention is not limited thereto.

  The azo metal complex dye in the present invention may have different coordination structures and metal ion valences depending on the existing environment (in a solvent, in a powder state, etc.). When the coordination structures are different, possible coordination structures include a pentanuclear complex formed from five transition metal ions and four azo dyes, or a binuclear complex formed from two transition metal ions and two azo dyes. There is. It is also conceivable that it exists as a mixture thereof. In addition, since the charge and number of the counter salt may change when the valence of the metal ion changes, the counter salt of the metal chelate dye between the azo dye and the transition metal ion is not particularly limited, and neutralizes the charge. It is only necessary to form a counter salt with ions necessary for the purpose. Examples of ions forming the counter salt include, but are not limited to, ions exemplified as ions represented by G in the general formula (F) described later.

  Examples of the general synthesis method of the azo dye represented by the general formula (1) 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.

  As a general method for obtaining a metal azo chelate dye by reacting an azo dye with a transition metal ion, an azo dye, a metal salt (including a metal complex or a metal oxide salt) in an organic solvent, water, or a mixture thereof. And a method of stirring. When synthesizing the azo metal complex dye used in the present invention, it is preferable to react in the presence of a base in order to obtain an azo metal complex dye containing two or more transition metal ions in one molecule. The azo metal complex dye containing the azo dye represented by the general formula (1) as a ligand is obtained by reacting the azo dye represented by the general formula (1) with a transition metal ion in the presence of a base. It is preferable. The recording layer containing the azo metal complex dye thus obtained usually contains a base in the azo metal complex and / or in the recording layer.

As an azo metal complex dye obtained by reacting an azo dye represented by the general formula (1) with a transition metal ion, an azo metal complex represented by the following general formula (F) or general formula (H) A dye is preferred. The azo metal complex dye represented by the general formula (F) is formed by five copper ions and four azo dyes represented by the general formula (1). In both the general formula (F) and the general formula (H), transition metal ions are bonded to two nitrogen atoms on the pyrazole ring represented by the general formula (A). It is considered that these structures are stabilized by the dissociation of the hydrogen atom represented by Y ¹ .

［一般式（Ｆ）中、Ｌ^2-は下記一般式（２）で表されるアゾ色素から水素原子２つが解離した２価アニオンを表し、Ｇは電荷を中和するために必要なイオンを表し、ｖは０〜２の範囲の整数を表し、Ｌ’は配位子を表し、ｘは０〜６の範囲の整数を表す。］

［一般式（２）中、Ｙ¹¹は上記２つの水素原子のうちの一方の水素原子を含有する基を表し、Ｙ¹²は上記２つの水素原子のうちの他方の水素原子を表し、Ｒ¹¹は、炭素数２〜１０の置換もしくは無置換のアルキルオキシカルボニル基またはシアノ基を表し、Ｒ¹²は水素原子または置換基を表し、下記部分構造：

は、下記部分構造式（Ｅ−１）〜（Ｅ−６）、または（Ｅ−８）のいずれかを表す。］

[上記において、Ｒ⁴¹〜Ｒ⁵⁶、Ｒ⁵⁹〜Ｒ⁶²は、各々独立に水素原子または置換基を表し、隣接する置換基は互いに連結して環を形成してもよい。但し、Ｒ⁴⁶〜Ｒ⁴⁹が置換基を表す場合、該置換基はアミノ基、ヒドロキシル基、アルコキシ基およびアリールオキシ基以外の置換基である。] Below, general formula (F) is demonstrated.

[In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from the azo dye represented by the following general formula (2), and G represents an ion necessary for neutralizing the charge. V represents an integer in the range of 0 to 2, L ′ represents a ligand, and x represents an integer in the range of 0 to 6. ]

[In General Formula (2), Y ¹¹ represents a group containing one of the two hydrogen atoms, Y ¹² represents the other hydrogen atom of the two hydrogen atoms, R ¹¹ Represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, R ¹² represents a hydrogen atom or a substituent, and has the following partial structure:

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8). ]

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]

In general formula (F), L ′ represents a ligand. In the present invention, the “ligand” refers to an atom or atomic group capable of binding to a metal ion. When a plurality of L ′ are present, the plurality of L ′ may be the same as or different from each other.
As the ligand represented by L ′, in addition to the ligands mentioned in the preferred examples described below, for example, “Photochemistry and Photophysics of Coordination Compounds” (Springer-Verlag, H. Yersin, published in 1987), “Organometallic Chemistry-Fundamentals and Applications” (Takahafusa Co., Ltd., Akio Yamamoto, published in 1982) and the like. Specific examples of the ligand will be described below.

  The atom contained in L ′ and coordinated to the metal ion is preferably a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, or a halogen atom (a chlorine atom, a fluorine atom, a bromine atom, an iodine atom, etc.), and nitrogen. An atom, an oxygen atom and a halogen atom are more preferred, a nitrogen atom and an oxygen atom are further preferred, and a nitrogen atom is particularly preferred.

  When L ′ is coordinated to a metal ion, L ′ may be an anionic ligand or a neutral ligand.

  Among the above, L ′ coordinated to a metal ion with a nitrogen atom is not particularly limited, but a nitrogen-containing aromatic heterocyclic ligand {for example, a pyridine ligand, a pyrazine ligand, a pyrimidine ligand , Pyridazine ligand, triazine ligand, thiazole ligand, oxazole ligand, pyrrole ligand, imidazole ligand, pyrazole ligand, triazole ligand, oxadiazole ligand, thiadiazole ligand Ligands and condensed ligand bodies containing them (for example, quinoline ligands, benzoxazole ligands, benzimidazole ligands, and the like, and tautomers thereof), amine ligands (for example, , Ammonia, methylamine, dimethylamine, diethylamine, dibenzylamine, triethylamine, piperidine, piperazine, morpholine, arylamine ), Aniline ligands (eg, aniline, N-methylaniline, N, N-dimethylaniline, N, N-diethylaniline, diphenylamine, N-acylaniline, N-alkylsulfonylaniline, etc.), imine ligands , Nitrile ligand (eg acetonitrile ligand etc.), isonitrile ligand (eg t-butyl isonitrile ligand etc.), amide ligand (eg dimethylformamide ligand, dimethylacetamide ligand etc.), Amidine ligands (for example, DBU, DBN), guanidine ligands (for example, tetramethylguanidine) and the like can be mentioned. These ligands may have a substituent.

L ′ coordinated to the metal ion with an oxygen atom is not particularly limited, but an alcohol ligand (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 10 carbon atoms). For example, monovalent anionic ligands obtained by dissociating protons such as methanol, ethanol, butanol and 2-ethylhexyloxy), aryloxy ligands (preferably having 6 to 30 carbon atoms, more preferably Is a C6-C20, particularly preferably C6-C12, and examples thereof include monovalent anionic ligands obtained by dissociating protons such as phenol, 1-naphthol and 2-naphthol.), Diketone coordination Child (for example, acetylacetone ligand), silyloxy ligand (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably carbon 3 to 24, for example, trimethylsilyloxy, triphenylsilyloxy, etc.), ether ligand (including cyclic ether) carboxylic acid ligand, sulfonic acid ligand, aqua ligand, O ₂ ligands etc. are mentioned. These ligands may have a substituent.

  L ′ coordinated to a metal ion with a sulfur atom is not particularly limited, but an alkylthiol ligand (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, and particularly preferably 1 to 12 carbon atoms). For example, monovalent anionic ligands with protons dissociated such as butanethiol), arylthiol ligands (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably Has 6 to 12 carbon atoms, and examples thereof include thiophenol.), And thioether ligands. These ligands may have a substituent.

  L ′ coordinated to a metal ion with a phosphorus atom is not particularly limited, but is an alkylphosphine ligand (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, and particularly preferably 2 to 10 carbon atoms). For example, methylphosphine, dimethylphosphine, diethylphosphine, dibenzylphosphine, etc.), arylphosphine ligands (preferably having 3 to 30 carbon atoms, more preferably 4 to 20 carbon atoms, particularly preferably C5-C10, for example, phenylphosphine, diphenylphosphine, pyridylphosphine, etc.). These ligands may have a substituent.

In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from an azo dye represented by the following general formula (2).

In general formula (2), Y ¹¹ represents a group containing one hydrogen atom of the two hydrogen atoms dissociating. The details are the same as Y ¹ in the general formula (1). Y ¹² represents the other hydrogen atom of the two dissociated hydrogen atoms.

R ¹¹ represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, and R ¹² represents a hydrogen atom or a substituent. R ¹¹ is preferably a cyano group from the viewpoint of recording characteristics. R ¹² is preferably a substituent from the viewpoint of solubility, and details of these groups are as described for R ¹ and R ² in the general formula (1).

は、前記部分構造式（Ｅ−１）〜（Ｅ−６）、または（Ｅ−８）のいずれかを表す。それらの詳細は、先に説明した通りである。 In the general formula (2), the following partial structure:

Represents any of the partial structural formulas (E-1) to (E-6) or (E-8). Details thereof are as described above.

In general formula (F), G represents an ion necessary for neutralizing the charge, and v represents an integer in the range of 0-2.
G may vary depending on the valence of Cu. When all Cu is present as a divalent cation, the counter anion in the Cu salt that is a raw material for synthesizing the azo metal complex can be G. Examples of G include acetate anion, anion in which one hydrogen atom is dissociated from acetylacetone, halogen ion, sulfate ion, nitrate ion, hydroxide ion, and the like. Cu is stable as monovalent depending on the environment in which it exists, in which case G may be a cation. Examples of the cation include those in which the base used in the synthesis is protonated. The base is preferably an organic base, and examples of the organic base include C1-C30 primary to tertiary amines (for example, triethylamine, diisopropylamine, pyrrolidine, N-methylpyrrolidine, n-butylamine, etc.), amidines {for example , DBU (1,8-diazabicyclo [5.4.0] -7-undecene), DBN (1,5-diazabicyclo [4.3.0] -5-nonene), etc.}, guanidines (for example, tetramethyl Guanidine, etc.), nitrogen-containing heterocycles (eg, pyridine, imidazole, etc.), tetrabutylammonium hydroxide and the like. As an organic base, a C1-C30 primary to tertiary amine is preferable, a C1-C20 primary to tertiary amine is more preferable, a C1-C10 primary to tertiary amine is more preferable, A secondary or tertiary amine having a number of 1 to 10 is particularly preferred.

  If Cu is all divalent, v is 2, and if Cu1 is present, it is considered to be an integer in the range of 0-2.

  In general formula (F), x represents an integer in the range of 0-6. From the viewpoint of recording characteristics, x is preferably an integer in the range of 0 to 4, more preferably an integer in the range of 0 to 3, further preferably an integer in the range of 0 to 2, Or 1 is particularly preferred. This is because the smaller the x, the higher the content of the azo ligand per molecule, and an improvement in recording sensitivity is expected.

  In the azo metal complex dye represented by the general formula (F), the azo ligand is present as a divalent anion as follows. However, the two anions on the ligand are not necessarily localized as described below, and include cases where they are delocalized.

[上記において、Ｚ¹¹は一般式（２）中のＹ¹¹から水素原子１つが脱離した基であり、Ｑ¹、Ｒ¹¹およびＲ¹²は一般式（２）と同義である。]

[In the above, Z ¹¹ is a group in which one hydrogen atom is eliminated from Y ¹¹ in the general formula (2), and Q ¹ , R ¹¹ and R ¹² have the same meaning as in the general formula (2). ]

Here, the X-ray structure of the azo metal complex obtained by reacting the compound (A-0), which is an analog of the azo metal complex dye represented by the general formula (F), with copper ion in the presence of triethylamine The structure revealed by the analysis 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. Ligand 1 is called ligand 1 (1) to ligand 1 (3), and ligand 2 is called ligand 2 (1) to ligand 2 (3). In the chelate, 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, the third copper ion is bound to ligand 2 (1) and ligand 4 (2), and the fourth copper ion is bound to ligand 3 (2) and ligand 4 (1). Ligand 1 (3), Ligand 2 (3), Ligand 3 (3) are bonded to the fifth copper ion located in the center surrounded by the first to fourth copper ions. And confirmed that the ligand 4 (3) is bonded. Came.
The coordination structure of the azo metal complex belonging to the general formula (F) can also have a coordination structure similar to the above coordination structure. However, the constituent elements in the molecule are not limited to azo dyes and transition metal ions, and include cases in which coexisting anion species, cation species, solvent molecules, and bases are added.

Note that the azo metal complex obtained by reacting the compound (A-0) with copper ion in the presence of triethylamine or the azo metal complex of the present invention synthesized in the same manner is identified by various MSs. When the molecular weight of a molecule formed from four ligand molecules and five transition metal molecules is M, when M peak is detected, when M / 2 peak is detected by nega, two azo dyes When a peak corresponding to a molecule formed from two transition metal ions is detected, a peak corresponding to a molecule formed from two azo dyes and three transition metal ions may be detected. Single bases can also be detected. Monodentate ligands (bases, solvents, etc.) are rarely detected as complexes and are detected as fragments. It can be confirmed that a base or the like is included as a part of the complex by thermal analysis (for example, TG / DTA or the like) such that the temperature of starting weight reduction of the azo metal complex is higher than the boiling point of the base or solvent.
On the other hand, even if the peak of a molecule formed from two azo dyes and two transition metal ions is detected by MS, if the Cu content is analyzed by ICP or the like, the base is zero in four azo dyes and five transition metal ions. It may coincide with a molecule containing ~ several. In some cases, two azo dyes and two transition metal ions coincide with each other in molecules containing 0 to several bases. In the case of identification by ESI-MS or MALDI-MS, two azo dyes and two transition metal ions, and two azo dyes and two transition metal ions, and two azo dyes and three transition metal ions are observed as fragments. There are many cases. The azo metal complex dye contained in the recording layer of the optical information recording medium of the present invention contains two or more transition metal ions in one molecule.
(1) The result of containing two azo dyes and two transition metal ions in one molecule by at least one analysis selected from the group consisting of ESI-MS, MALDI-MS and X-ray structure analysis, and,
(2) showing a result of containing four azo dyes and five transition metal ions in one molecule by at least one analysis selected from the group consisting of ESI-MS, MALDI-MS and X-ray structure analysis;
Can be mentioned.

  It may be identified as a molecule formed from two azo dyes and two transition metal ions by measuring both MS and Cu content. Such azo metal complex dyes are represented by the following general formula (H). The azo metal complex dye represented by these is preferable. Having the structure represented by the general formula (H) can be confirmed by X-ray structural analysis.

Next, general formula (H) will be described. In the present invention, a solid line connecting two atoms in the structural formula represents a covalent bond, and a broken line represents a coordination bond.

中のＹ¹¹から水素原子が１つ解離した基を表し、上記部分構造、Ｒ¹¹およびＲ¹²は、それぞれ一般式（Ｆ）における定義と同義であり、その詳細は前述の通りである。一般式（Ｈ）中にそれぞれ２つ存在するＱ¹¹、Ｚ¹¹、Ｒ¹¹およびＲ¹²は互いに同一でも異なっていてもよい。 In general formula (H), Z ¹¹ represents the following partial structure:

Represents a group in which one hydrogen atom is dissociated from Y ¹¹ therein, and the partial structures R ¹¹ and R ¹² have the same definitions as in general formula (F), and the details thereof are as described above. Two Q ^{11 s} , Z ^{11 s} , R ^{11 s} and R ^{12 s} each present in the general formula (H) may be the same as or different from each other.

L ¹¹ and L ¹² each independently represents a ligand. L ¹¹ and L ¹² are respectively synonymous with the aforementioned L ′, and details such as preferred ranges are also the same.

n ¹¹ and n ¹² represents an integer in the range of independently 0-2. When a plurality of L ¹¹ and L ¹² are present, the plurality of L ¹¹ and L ¹² may be the same as or different from each other.

は前記（Ｅ−１）〜（Ｅ−３）、（Ｅ−８）のいずれかがであり、かつ、Ｌ’は有機塩基である。より好ましくは、Ｒ¹¹はシアノ基であり、かつ、Ｒ¹²は炭素数２〜４の置換もしくは無置換のアルキル基であり、かつ、下記部分構造：

は前記（Ｅ−１）、（Ｅ−３）、（Ｅ−８）のいずれかがであり、かつ、Ｌ’は有機塩基であり、さらに好ましくは、Ｒ¹¹はシアノ基であり、かつ、Ｒ¹²は炭素数２〜３の置換もしくは無置換のアルキル基であり、かつ、下記部分構造：

は前記（Ｅ−１）、（Ｅ−３）のいずれかがであり、かつ、Ｌ’は有機塩基である。さらに好ましくは、Ｒ¹¹はシアノ基であり、かつ、Ｒ¹²は炭素数３〜４の置換もしくは無置換のアルキル基であり、かつ、下記部分構造：

は前記（Ｅ−１）、（Ｅ−３）のいずれかがである。 In the general formula (F), preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and the following partial structure:

Is any one of the above (E-1) to (E-3) and (E-8), and L ′ is an organic base. More preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 2 to 4 carbon atoms, and the following partial structure:

Is any one of the above (E-1), (E-3), and (E-8), L ′ is an organic base, more preferably R ¹¹ is a cyano group, and R ¹² is a substituted or unsubstituted alkyl group having 2 to 3 carbon atoms, and has the following partial structure:

Is either (E-1) or (E-3), and L ′ is an organic base. More preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 3 to 4 carbon atoms, and the following partial structure:

Is either (E-1) or (E-3).

は前記（Ｅ−１）〜（Ｅ−３）、（Ｅ−８）のいずれかについてＹ¹¹部に含まれる水素原子を一つ解離させたものであり、かつ、Ｌ’は有機塩基であり、より好ましくは、Ｒ¹¹はシアノ基であり、かつ、Ｒ¹²は炭素数２〜４の置換もしくは無置換のアルキル基であり、かつ、下記部分構造：

は前記（Ｅ−１）、（Ｅ−３）、（Ｅ−８）のいずれかのＹ¹¹部に含まれる水素原子を一つ解離させたものであり、かつ、Ｌ’は有機塩基であり、さらに好ましくは、Ｒ¹¹はシアノ基であり、かつ、Ｒ¹²は炭素数２〜３の置換もしくは無置換のアルキル基であり、かつ、下記部分構造：

は前記（Ｅ−１）、（Ｅ−３）のいずれかのＹ¹¹部に含まれる水素原子を一つ解離させたものであり、かつ、Ｌ’は有機塩基である。Ｑ¹¹とＺ¹¹を含む前記部分構造は、（Ｅ−１）、（Ｅ−３）、（Ｅ−８）のいずれかのＹ¹¹部に含まれる水素原子を一つ解離させたものであることが更に好ましく、（Ｅ−１）、（Ｅ−８）のいずれかのいずれかのＹ¹¹部に含まれる水素原子を一つ解離させたものであることが特に好ましい。 In the general formula (H), preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and the following partial structure:

Is the (E-1) ~ (E -3), are those obtained by one dissociating hydrogen atoms contained in Y ¹¹ parts for either (E-8), and, L 'is an organic base More preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 2 to 4 carbon atoms, and the following partial structure:

Is obtained by dissociating one hydrogen atom contained in Y ¹¹ part of any one of (E-1), (E-3) and (E-8), and L ′ is an organic base. More preferably, R ¹¹ is a cyano group, R ¹² is a substituted or unsubstituted alkyl group having 2 to 3 carbon atoms, and has the following partial structure:

Is obtained by dissociating one hydrogen atom contained in Y ¹¹ part of either (E-1) or (E-3), and L ′ is an organic base. The partial structure containing Q ¹¹ and Z ¹¹ is obtained by dissociating one hydrogen atom contained in the Y ¹¹ part of any one of (E-1), (E-3), and (E-8). Is more preferable, and it is particularly preferable that one hydrogen atom contained in Y ¹¹ part of either (E-1) or (E-8) is dissociated.

  As a specific example of the general formula (H), the compound (M-35) described later was found to have the following structural formula from the results of X-ray structural analysis. A single crystal was produced by dissolving (M-35) in DMAc and storing it in a methanol atmosphere for a long period of time. Although this compound detected both a peak corresponding to the general formula (F) and a peak corresponding to the following structure in ESI-MS, it can be identified as the following structure from the X-ray structural analysis results. It was. In addition, the absorption spectrum waveform in chloroform matched the powder used for single crystal and single crystal preparation.

The azo metal complex dye represented by the general formula (F) or the general formula (H) can be obtained by reacting the azo dye represented by the general formula (1) with a Cu salt. The reaction is preferably performed in the presence of a base, and the base is preferably an organic base. This is because when an inorganic base is used, the metal ion in the base forms an ion pair with the azo ligand, making it difficult to obtain a desired azo metal complex. Examples of the organic base include the aforementioned organic bases. As the solvent, for example, an alcohol such as methanol can be used. The ligand is represented by L ′ in the general formula (F) or L ¹¹ or L ¹² in the general formula (H). Since the ligand is derived from a base or a solvent, an azo metal complex dye having a desired ligand can be obtained by selecting the base and the solvent. Moreover, in this invention, the kind of metal salt, the kind of base, the kind of organic solvent or its liquid mixture, reaction temperature, etc. are not limited. The reaction conditions such as 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. Obtaining the target azo metal complex dye can be confirmed by known methods such as ESI-MS, MALDI-MS, ESR, X-ray structural analysis, and ICP. Which of the general formula (F) and the general formula (H) is generated depends on the kind of the azo ligand. All are excellent in recording / reproduction characteristics, light resistance, and reproduction durability by irradiation with a recording short wavelength laser beam.

  Specific examples of the azo metal complex dye represented by the general formula (F) or the general formula (H) are shown below. However, the present invention is not limited to the following specific examples. For the reasons described above, the compounds shown in the following specific examples can take the structure of any one or both of general formula (F) and general formula (H).

  The optical information recording medium of the present invention contains at least one kind of the azo metal complex dye in the recording layer. The azo metal complex dye contained in the recording layer may be one kind or two or more different kinds. 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 may have at least one recording layer on the substrate (on the surface having a pregroove with a track pitch of 50 to 500 nm), and may have two or more recording 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 has absorptivity with respect to laser light having a wavelength 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 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. .

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 surface of the substrate on the side where the light reflecting layer, which will be 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. 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.

  Preferred embodiments of the optical information recording medium of the present invention include the following embodiments (1) and (2).

Aspect (1): Optical information recording medium having a write-once recording layer containing a dye and a cover layer having a thickness of 0.01 to 0.5 mm in order from the substrate side on a substrate having a thickness of 0.7 to 2 mm Aspect (2): Optical information having a write-once recording layer containing a dye and a protective substrate having a thickness of 0.1 to 1.0 mm in order from the substrate side on a substrate having a thickness of 0.1 to 1.0 mm. recoding media

  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. In aspect (2), the substrate It is preferable that the track pitch of the pregroove formed is 200 to 500 nm, the groove width is 50 to 300 nm, the groove depth is 30 to 150 nm, and the wobble amplitude is 5 to 50 nm.

[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.
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 one by one.

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 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.

In addition, 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 350399, and Japan Examples include those described in Chemical Society Journal, October 1992, page 1141.
The amount of the antifading agent such as the singlet oxygen quencher used 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-based, 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 be 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 reflectivity, 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, a material made of nitride, oxide, carbide, sulfide such as Zn, Si, Ti, Te, Sn, Mo, Ge, Nb, Ta is preferable. MoO ₂ , GeO ₂ , TeO, SiO ₂ ,
TiO _2, ZnO, preferably _{SnO 2, ZnO-Ga 2 O} 3, Nb 2 O 5, Ta 2 O 5, SnO 2, ZnO-Ga 2 O 3, is _{SiO 2, Nb 2 O 5,} Ta 2 O 5 More preferred.

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.

  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) 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 through 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 blue-violet semiconductor laser light having an oscillation wavelength in the range of 390 to 415 nm in terms of recording density. The optical information recording medium of aspect (1) has a reflective layer between the substrate and the write-once recording layer as described above, and recording is performed from the cover layer side, that is, the surface side opposite to the surface facing the reflective layer. The layer is irradiated with laser light.

  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.

Furthermore, the present invention relates to an azo metal complex dye represented by the above general formula (F) or (H).
The azo metal complex dye of the present invention can be used for various applications such as pigments, photographic materials, UV absorbing materials, color filter dyes, and color conversion filters. Preferably, it is used as a recording layer dye in an optical information recording medium having a dye-containing recording layer. 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-13)]

2 ml of acetic acid and 4 ml of propionic acid were poured into a 100 ml Erlenmeyer flask, and 2.23 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 an aqueous solution in which 0.52 g of NaNO ₂ was dissolved was slowly added dropwise thereto, followed by stirring at 0 to 5 ° C. for 1 hour. This acidic solution was gradually added to 15 ml of a methanol solution containing 1.13 g of compound (2) kept at 0 to 5 ° C. under ice cooling, and stirred for 1 hour. After returning to room temperature and stirring for 2 hours, the mixture was cooled in an ice bath. The precipitate was filtered and washed with a minimum amount of methanol and distilled water. The obtained solid was dried to obtain 1.13 g of compound (L-13). The compound was identified by 300 MHz ¹ H-NMR.
¹ H-NMR (DMSO-d6) [ppm]; δ13.44 (1H, s), 3.30 (3H, s), 2.80-2.74 (2H, q), 1.33 (9H, s), 1.29-1.25 (9H , t)

(L-1) to (L-18), (L-20) to (L-31), and (L-33) were synthesized by the same method as the synthesis of the compound (L-13) described above. Various azo dyes that can be used in the present invention can be synthesized in the same manner. The compound was identified by 300 MHz ¹ H-NMR. A part of the NMR spectrum data is shown below.

(L-1) ¹ H-NMR (DMSO-d6) [ppm]; δ13.70 (1H, br), 13.31 (1H, s), 3.331 (3H, s), 1.413 (9H, s), 1.331 ( 9H, s)
(L-3) ¹ H-NMR (DMSO-d6) [ppm]; δ13.93 (1H, s), 10.20 (1H, s), 7.63-7.57 (2H, m), 7.06 (1H, d), 1.45 (9H, s), 1.30 (9H, s)
(L-4) ¹ H-NMR (DMSO-d6) [ppm]; δ 14.68 (1H, br), 13.53 (1H, s), 8.32 (3H, s), 3.82 (2H, t), 1.53 ( 2H, tt), 1.31 (2H, tq), 0.90 (3H, t)
(L-5) ¹ H-NMR (DMSO-d6) [ppm]; δ13.43 (1H, br), 13.20 (1H, br), 7.40-7.36 (8H, m), 7.24-7.21 (2H, m ), 1.41 (9H, s)
(L-6) ¹ H-NMR (DMSO-d6) [ppm]; δ 14.20 (1H, s), 13.40 (1H, s), 3.22 (3H, s), 3.20 (3H, s), 1.42 ( 9H, s)
(L-8) ¹ H-NMR (DMSO-d6) [ppm]; δ 13.42 (1H, br), 8.30-7.60 (4H, br), 1.40 (9H, s)
(L-10) ¹ H-NMR (DMSO-d6) [ppm]; δ13.78 (1H, s), 13.30 (1H, s), 8.38 (1H, s), 4.31 (q), 3.34 (3H, s), 1.36-1.31 (12H, m)

  Next, although the specific example of the synthesis method of the azo metal complex pigment | dye represented by exemplary compound (M-13) is shown, this invention is not limited to these methods.

[Synthesis of (M-13)]
A 50 ml eggplant flask was charged with 0.7 g of the compound (L-13) and 7 ml of ethanol, and 1 ml of DBU was added dropwise with stirring. While stirring, 380 mg of copper acetate monohydrate was further added, and the mixture was heated to reflux for 3 hours. It returned to room temperature and 30 ml of distilled water was added, and precipitation was produced | generated. The resulting precipitate was filtered and washed with distilled water. Drying was performed to obtain 0.74 g of the compound (M-13). The compound was identified by Cu content measurement using ICP-OES and ESI-MS.
ESI-MS: m / z = 1515 (nega), 785 (nega), 725 (posi)
From the results of ESI-MS, both the peak of the complex consisting of 4 azo dyes and 5 copper ions and the peak of the complex consisting of 2 azo dyes and 2 copper ions were detected.
ICP-OES: Cu content = 163 ± 4 g / kg
From the results of ICP-OES, it was consistent with a structure in which two DBUs and two acetate ions were included in a complex composed of four azo dyes and five copper ions. The Cu content was higher than that of the complex composed of two azo dyes and two copper ions.

Under the same conditions as (M-13), (M-8), (M-11), (M-18), (M-20), (M-21), (M-26), (M -34), (M-35), and (M-38) were synthesized.
(M-21): (ICP-OES) 140 ± 5 g / kg
From the results of ICP-OES, the results are consistent with a structure in which one DBU is contained in a complex composed of two azo dyes and two copper ions.
(M-35): (ESI-MS) m / z = 949 (nega), 920 (posi), 915 (nega)
As for (M-35), both the peak of the complex consisting of 4 azo dyes and 5 copper ions and the peak of the complex consisting of 2 azo dyes and 2 copper ions were detected from the results of ESI-MS.
As described above, (M-35) was a complex composed of two azo dyes and two copper ions in the X-ray structural analysis results.

[Synthesis of (M-1)]
A 50 ml eggplant flask was charged with 0.7 g of compound (L-1) and 10 ml of methanol, and 1.5 ml of triethylamine was added dropwise with stirring. While stirring, 430 mg of copper acetate monohydrate was further added, and the mixture was heated to reflux for 3 hours. The temperature was returned to room temperature, and the resulting precipitate was filtered and washed with methanol. Drying was performed to obtain 0.44 g of compound (M-1). The compound was identified by Cu content measurement using ICP-OES, ESI-MS and MALDI-MS.
ICP-OES: Cu content = 172 g / kg
From the results of ICP-OES, the results were consistent with a structure comprising one triethylamine and two acetate ions in a complex composed of four azo dyes and five copper ions. The Cu content was higher than that of the complex composed of two azo dyes and two copper ions.
ESI-MS: m / z = 784 (posi), 782 (nega)
MALDI-MS: m / z = 784 (posi), 782 (nega), 102 (posi)
From the results of ESI-MS and MALDI-MS, a complex composed of two azo dyes and two copper ions and triethylamine were detected.

  Under the same conditions as (M-1), (M-1) to (M-6), (M-9), (M-15) and (M-28) were synthesized.

(M-9): (ESI-MS) m / z = 699 (nega), 699 (posi), 670 (nega)
As for (M-35), both the peak of the complex consisting of 4 azo dyes and 5 copper ions and the peak of the complex consisting of 2 azo dyes and 2 copper ions were detected from the results of ESI-MS.

  In the synthesis of (M-1), (L-1) was replaced with (L-16), triethylamine was replaced with diisopropylamine, and (M-16) was synthesized by reacting in the same manner.

  In the synthesis of (M-1), (L-1) was replaced with (L-11), triethylamine was replaced with diisopropylamine, and (M-27) was synthesized by reacting in the same manner.

  In the synthesis of (M-1), (L-1) was replaced with (L-14), triethylamine was replaced with diisopropylamine, and (M-29) was synthesized by reacting in the same manner.

  In the synthesis of (M-1), (L-1) was replaced with (L-24), triethylamine was replaced with DBN, and (M-37) was synthesized by reacting in the same manner.

  Various azo metal complex dyes that can be used in the optical information recording medium of the present invention can be synthesized by the same method as the above-described compound synthesis method. The identity of the compound can be confirmed by MALDI-MS, ESI-MS, ESR, ICP-OES, X-ray structural analysis and the like. The measuring method by ICP-OES is shown below.

≪Measurement of ICP-OES (ICP emission spectroscopy) ≫
A sample of 0.05 g was collected, and after adding 3 ml of nitric acid, microwave ashing was performed. The volume was made up to 100 ml with water, and Cu was quantified with ICP-OES (Shimadzu 1000-IV) using the absolute calibration curve method.

<< Production of optical information recording medium >>
(Production of substrate)
Thickness 1.1 mm, outer diameter 120 mm, inner diameter 15 mm and spiral pre-groove (track pitch: 320 nm, groove width: groove (recess) width 170 nm, groove depth: 37 nm, groove inclination angle: 52 °, 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 16, compounds (M-1) to (M-6), (M-8), (M-13), (M-15), (M-16), (M-21), 1 g of each of (M-26), (M-27), (M-28), (M-34), and (M-35) was added to 100 ml of 2,2,3,3-tetrafluoropropanol. It melt | dissolved and the pigment-containing coating liquid was prepared. 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 through 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 16 were manufactured.

<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 7: Production of Optical Information Recording Medium Comparison was made in the same manner except that Comparative Compounds (A) to (G) were used in place of Illustrative Compound (M-1) as the dye used for the write-once recording layer. The optical information recording media of Examples 1 to 7 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 16 and Comparative Examples 1 to 7 are prepared, and the prepared pigment-containing coating solution is prepared on a glass plate having a thickness of 1.1 mm. The coating was performed at room temperature in a nitrogen atmosphere while changing the rotational speed from 500 to 1000 rpm by a spin coating method. Then, after storing at room temperature for 24 hours, a light resistance test was performed 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.

  (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 3, compared with Comparative Examples 1 to 7 using conventional azo metal complexes, in Examples 1 to 16, both light resistance and recording / reproduction characteristics can be achieved. As a good property. As the metal ion, the azo metal complex dye of the present invention containing Cu ions is more excellent in light resistance than the dye containing Ni ions and Co ions that have been used favorably in azo metal complexes so far. In addition, it was found that the recording / reproducing characteristics were also superior. In all the examples, recording / reproduction of the optical information recording medium after irradiation with Xe light for 55 hours was possible, and light resistance was good even under the optical information recording medium.

  In addition, the azo metal complex dye used in the examples exhibited good solubility in the coating solvent and good film stability. The optical information recording medium produced in Example 1 was stored under high temperature and high humidity for 168 hours after recording, but it was found that there was almost no change in jitter and the storage stability under high temperature and high humidity was extremely excellent.

  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 compound (M-2 ), (M-8), (M-11), (M-13), (M-15), (M-16), (M-21), (M-26), (M-27), It was found that (M-29), (M-34), and (M-35) had almost no change in absorption spectrum under the same conditions and were excellent in stability.

  In addition, as for (M-1) and (M-15), as a result of storing a dye film produced in the same manner as in the light resistance evaluation at 60 ° C. and 90% RH for 24 hours, almost no change in absorption was observed, and high temperature and high humidity It was found to be excellent under stability.

  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. Since it is excellent in light resistance and stability under high temperature and high humidity, it has been found that it has desirable properties in various applications such as photographic materials, color filter dyes, color conversion filters, thermal transfer recording materials, and inks.

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 / reproducing characteristics and extremely high light resistance (particularly information by irradiation with laser light having a wavelength of 440 nm or less). Can be produced.
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 type recording layer 16 ... cover layer 18 ... 1st light reflection layer 20 ... barrier layer 22 ... 1st adhesion layer or 1st adhesion layer 44 ... hardware Coat layer

Claims (15)

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 includes an azo metal complex dye that is a complex of an azo dye and a transition metal ion equal to or more than the number of the azo dyes, and two or more of the azo metal complex dyes per molecule. Wherein a plurality of transition metal ions contained in one molecule of the azo metal complex dye may be the same or different, and a plurality of azo dyes may be contained in one molecule of the azo metal complex dye. When included, the plurality of azo dyes may be the same or different, respectively. The azo metal complex dye contains two azo dyes and two transition metal ions in one molecule by at least one analysis selected from the group consisting of ESI-MS, MALDI-MS, and X-ray structural analysis. The optical information recording medium according to claim 1, wherein: The azo metal complex dye contains four azo dyes and five transition metal ions in one molecule according to at least one analysis selected from the group consisting of ESI-MS, MALDI-MS, and X-ray structural analysis. The optical information recording medium according to claim 1, wherein: The optical information recording medium according to claim 1, wherein the azo dye is an azo dye having a partial structure represented by the following general formula (A).

[In General Formula (A), R ¹ and R ² each independently represent a hydrogen atom or a substituent, Y ¹ represents a hydrogen atom that may be dissociated in the recording layer, and * represents —N═ This represents the bonding position with the N-group. ] The optical information recording medium according to claim 4, wherein the azo dye is an azo dye represented by the following general formula (1).

[In General Formula (1), Q ¹ represents an atomic group forming a heterocyclic ring or a carbocyclic ring, Y represents a group containing a hydrogen atom which may be dissociated in the recording layer, and R ¹ , R ² And Y ¹ have the same definitions as in general formula (A). ] 6. The optical information recording medium according to claim 5, wherein the azo metal complex dye is obtained by reacting the azo dye represented by the general formula (1) with a transition metal ion in the presence of a base. The optical information recording medium according to claim 1, wherein the recording layer contains a base. The following partial structure in the general formula (1):

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8): The optical information recording medium according to any one of claims 5 to 7.

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ] The optical information recording medium according to claim 1, wherein the transition metal ion is a copper ion. The optical information recording medium according to any one of claims 4 to 9, wherein R ¹ is a substituted or unsubstituted alkyloxycarbonyl group having 2 to 10 carbon atoms, or a cyano group. The optical information recording medium according to claim 1, wherein the azo metal complex dye is an azo metal complex dye represented by the following general formula (F) or general formula (H).

[In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from the azo dye represented by the following general formula (2), and G represents an ion necessary for neutralizing the charge. V represents an integer in the range of 0 to 2, L ′ represents a ligand, and x represents an integer in the range of 0 to 6. ]

[In General Formula (2), Y ¹¹ represents a group containing one of the two hydrogen atoms, Y ¹² represents the other hydrogen atom of the two hydrogen atoms, R ¹¹ Represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, R ¹² represents a hydrogen atom or a substituent, and has the following partial structure:

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8). ]

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]

[In General Formula (H), Z ¹¹ represents the following partial structure:

Represents a group in which one hydrogen atom is dissociated from Y ¹¹ therein, and the partial structures, R ¹¹ and R ¹² , have the same definitions as in general formula (F), and two each in general formula (H). Q ¹¹ , Z ¹¹ , R ¹¹ and R ^{12 present} may be the same or different from each other, L ¹¹ and L ¹² each independently represent a ligand, and n ¹¹ and n ¹² are each independently 0 Represents an integer in the range of ~ 2. When a plurality of L ¹¹ and L ¹² are present, the plurality of L ¹¹ and L ¹² may be the same as 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. The optical information recording medium according to claim 12, further comprising a reflective layer between the substrate and the recording layer, wherein the laser light is applied to the recording layer 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 13 with a laser beam having a wavelength of 440 nm or less. An azo metal complex dye represented by the following general formula (F) or general formula (H).

[In the general formula (F), L ²⁻ represents a divalent anion in which two hydrogen atoms are dissociated from the azo dye represented by the following general formula (2), and G represents an ion necessary for neutralizing the charge. , V represents an integer in the range of 0 to 2, L ′ represents a ligand, and x represents an integer in the range of 0 to 6. ]

[In General Formula (2), Y ¹¹ represents a group containing one of the two hydrogen atoms, Y ¹² represents the other hydrogen atom of the two hydrogen atoms, R ¹¹ Represents a substituted or unsubstituted alkyloxycarbonyl group or cyano group having 2 to 10 carbon atoms, R ¹² represents a hydrogen atom or a substituent, and has the following partial structure:

Represents one of the following partial structural formulas (E-1) to (E-6) or (E-8). ]

[In the above, R ^{41 to} R ⁵⁶ and R ^{59 to} R ⁶² each independently represent a hydrogen atom or a substituent, and adjacent substituents may be linked to each other to form a ring. However, when R ^{46 to} R ⁴⁹ represent a substituent, the substituent is a substituent other than an amino group, a hydroxyl group, an alkoxy group, and an aryloxy group. ]

[In General Formula (H), Z ¹¹ represents the following partial structure:

Represents a group in which one hydrogen atom is dissociated from Y ¹¹ therein, and the partial structures, R ¹¹ and R ¹² , have the same definitions as in general formula (F), and two each in general formula (H). Q ¹¹ , Z ¹¹ , R ¹¹ and R ^{12 present} may be the same or different from each other, L ¹¹ and L ¹² each independently represent a ligand, and n ¹¹ and n ¹² are each independently 0 Represents an integer in the range of ~ 2. When a plurality of L ¹¹ and L ¹² are present, the plurality of L ¹¹ and L ¹² may be the same as or different from each other. ]

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