JPH11138998A - Information recording medium and oxonol compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a recording medium having high stability even in a light resistance and preservation durability with excellent recording and reproducing characteristics by using an oxonol dye represented by a specific formula with amidinium ion or diimmonium ion as paired ions, thereby incorporating excellent recording and reproducing characteristics. SOLUTION: A recording layer contains compounds (dyes) represented by formulae I and II. In the formulae, A<1> , A<2> , B<1> and B<2> are each independent y a substituent, X<1> is =O, =NR or =C(CN)2 , X<2> is -O, -NR or -C(CN)2 (where R is a substituent), L<1> to L<5> are each a methine which may be independently substituted, m, n are each independently 0, 1 or 2, k is an integer necessary to neutralize paired cations, R<1> to R<8> are each independently a hydrogen atom or a substituent, R<9> to R<13> are each independently a substituent, p is 1 or 2, and q and r are each independently an integer of 1 to 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium on which information can be written by using a laser beam having a high energy density, and a dye compound which can be advantageously used for manufacturing the information recording medium. .

[0002]

2. Description of the Related Art Conventionally, an information recording medium (optical disc) on which information can be recorded only once by a laser beam is also called a write-once CD (so-called CD-R), and is widely used, for example, as a disc memory for a computer. Have been. C
The basic structure of a DR type optical disk is a transparent disk-shaped substrate made of a polymer or the like, and Te, I
metal or semimetal such as n; or cyanine, metal complex,
A recording layer on which information can be recorded by a laser beam comprising a dye such as a quinone-based dye. Usually, a reflective layer made of gold or the like and a protective layer made of a resin are sequentially provided on the recording layer in a laminated state.

[0003] Writing (recording) of information on a CD-R type optical disk is usually performed by irradiating the optical disk with a laser beam having a wavelength of around 780 nm. Information is recorded by changing the optical characteristics of the optical device by causing a physical or chemical change (for example, generation of pits or the like) due to a temperature rise. On the other hand, reading (reproduction) of information is also usually performed by irradiating the optical disc with laser light having the same wavelength as the recording laser light, and a portion where the optical characteristics of the recording layer has changed (a recording portion due to pit generation or the like). ) And a portion that does not change (unrecorded portion) detect a difference in reflectance, thereby reproducing information.

A recording layer made of a dye can be easily formed by coating instead of a vapor deposition method like a metal, so that it is advantageous in terms of manufacturing cost and further has an advantage such as higher sensitivity than a metal recording layer. Having. However, the dye recording layer generally has problems such as low stability over time against heat or light. Therefore, development of a recording layer that can maintain stable performance against heat or light over a long period of time is desired. However, at present, a recording layer having satisfactory performance has not yet been developed.

Japanese Patent Application Laid-Open No. 63-209959 discloses an information recording medium in which a recording layer comprising an oxonol dye is provided on a substrate. It is said that by using this dye, stable recording / reproducing characteristics can be maintained for a long period of time. Here, an oxonol dye in which ammonium is introduced in the form of a salt in the molecule is described.

In recent years, an information recording medium having a higher recording density has been demanded. In order to increase the recording density, it is effective to reduce the diameter of the laser beam to be irradiated, and it is also effective to reduce the diameter of the laser beam with a shorter wavelength.
It is theoretically known that it is advantageous for high density. Therefore, the development of an optical disk for performing recording and reproduction using a laser beam having a wavelength shorter than 780 nm, which is generally used, has been promoted. For example, a write-once digital video disk (so-called DVD-R) has been developed. ) Has been proposed. The DVD-R type optical disk performs recording and reproduction by irradiating a visible laser beam (usually a laser beam having a wavelength in a range of 600 nm to 700 nm), and is compared with the above-mentioned CD-R type optical disk. It is said that higher density recording is possible.

[0007]

According to the study of the present inventors, the information recording medium containing an oxonol dye described in the above publication in the recording layer has a high storage stability and durability against heat (repeated reproduction). Although improved, it has been found that when exposed to light such as sunlight for a long time, poor reproduction is likely to occur, and the light resistance is still insufficient. In addition, this information recording medium has a lower reflectance than the information recording medium including a conventionally known cyanine dye in the recording layer, and also has sufficiently satisfactory recording / reproduction characteristics such as a low degree of modulation and a high jitter. It turned out to be nothing.

The main object of the present invention is to provide information having excellent recording / reproducing characteristics and high stability so that the recording characteristics can be sufficiently maintained for a long period of time, particularly high stability in light resistance and storage durability. To provide a recording medium (optical disk). Another object of the present invention is to provide a novel oxonol dye which can be advantageously used for producing an information recording medium having the above-mentioned high performance.

[0009]

According to the research of the present inventors,
In the conventional oxonol-based dye, by using a dye in which an aminium ion or a diimmonium ion represented by the above formula is newly introduced as a counter ion (cation), the recording / reproducing characteristics are superior to those of the related art, and the light resistance is higher. It has also been found that an information recording medium having further improved storage stability and high storage stability can be manufactured.

The present invention relates to an information recording medium having a recording layer on which information can be recorded by a laser beam on a substrate, wherein the recording layer is formed by the following general formulas (I-1) and (I-1). -2), general formula (I-3) and / or general formula (I-
An information recording medium comprising the compound (dye) represented by 4).

[0011]

Embedded image

[0012]

Embedded image

[In the formula, A ¹ , A ² , B ¹ and B ² each independently represent a substituent, and Y ¹ and Z ¹ each independently represent an atom necessary for forming a carbocyclic or heterocyclic ring. E and G each independently represent an atomic group necessary to complete a conjugated double bond chain; X ¹ represents ＝ O, ＮＲNR or ＣC (CN) ₂ , X ² Represents -O, -NR or -C (CN) ₂ (where R represents a substituent);
¹ , L ² , L ³ , L ⁴ and L ⁵ each independently represent a methine group which may be substituted, m and n each independently represent 0, 1 or 2, x and y each independently represent Represents 0 or 1 and k represents an integer required to neutralize the counter cation; R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R
⁷ and R ⁸ each independently represent a hydrogen atom or a substituent (provided that R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ and R
⁷ and R ⁸ may be linked together to form a heterocycle with the nitrogen atom), R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ are
Each independently represents a substituent, p represents 1 or 2, and q and r each independently represent an integer from 0 to 4.]

Further, the present invention provides a compound represented by the general formula (II-1), the general formula (II-2), the general formula (II-3) or the general formula (II-
There is also an oxonol compound represented by 4).

[0015]

Embedded image

[0016]

Embedded image

Wherein A ³ , A ⁴ , B ³ and B ⁴ each independently represent a linear, branched or cyclic C 1 -C 18
Alkyl group, alkenyl group having 2 to 18 carbon atoms, alkynyl group having 2 to 18 carbon atoms, aryl group having 6 to 18 carbon atoms, aralkyl group having 7 to 18 carbon atoms, acyl group having 2 to 18 carbon atoms, carbon group An alkyl or aryl sulfonyl group having 1 to 18 carbon atoms, an alkyl sulfinyl group having 1 to 18 carbon atoms,
An alkoxycarbonyl group having 6 to 18 carbon atoms, 7 to 7 carbon atoms
18 aryloxycarbonyl groups, C1-C18 alkoxy groups, C6-C18 aryloxy groups, C1-C18 alkylthio groups, C6-C18 arylthio groups, C2-C18 Acyloxy group, amide group having 1 to 18 carbon atoms, ureido group having 1 to 18 carbon atoms, sulfonyloxy group, carbamoyloxy group, amino group,
Carbamoyl group, sulfamoyl group, halogen atom, hydroxyl group, nitro group, cyano group, carboxyl group,
And one substituent selected from the group consisting of a 4- to 7-membered heterocyclic group (these substituents are further represented by A ³ , A
⁴ , may be substituted with at least one group selected from the group consisting of substituents represented by B ³ and B ⁴ );
² and Z ² each independently represent an atomic group necessary for forming a 4- to 7-membered carbon ring or a 4- to 7-membered heterocyclic ring (these rings are further represented by A ³ , A ⁴ , It may be substituted with at least one group selected from the group consisting of the substituents represented by B ³ and B ⁴ , and is condensed with a 4- to 7-membered carbon ring or a 4- to 7-membered heterocyclic ring. Or L)
⁶ , L ⁷ , L ⁸ , L ⁹ and L ¹⁰ are each independently the above-mentioned A
Represents a methine group which may be substituted with one or two groups selected from the group consisting of substituents represented by ³ , A ⁴ , B ³ and B ⁴ , wherein m 1 and n 1 are independently 0, 1 Or 2 and k1 represents an integer required to neutralize the counter cation; R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ ,
R ²⁷ and R ²⁸ each independently represent a hydrogen atom or the above-mentioned A
Represents one group selected from the group consisting of substituents represented by ³ , A ⁴ , B ³ and B ⁴ (provided that R ²¹ and R ²² , R ²³ and R ²⁴ , R ²⁵ and R ²⁶ and R ²⁷ And R ²⁸ may be linked together to form a heterocyclic ring with a nitrogen atom), R ²⁹ , R ³⁰ , R
³¹ , R ³² and R ³³ each independently represent A ³ , A ⁴ , B
Represents ³ and one group selected from the group consisting of substituents represented by B ^4, p1 is 1 or 2 and q1 and r1 each independently represent an integer of 0-4]

The information recording medium and the oxonol compound of the present invention are preferably in the following modes. (1) In the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4), R ^{1 to} R
⁸ are each independently a hydrogen atom, a halogen atom,
An alkyl group having 8 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or 1 to 8 carbon atoms
Represents an alkoxy group. (2) In the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4), R ¹ and R
² , ⁴ or 7 membered (more preferably 5 to 6 membered) unsubstituted heterocyclic ring formed by linking R ² and R ³ , R ⁵ and R ⁶ , and R ⁷ and R ⁸ together with a nitrogen atom. Is a heterocycle. (3) In the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4), R ^{9 to} R ^9
13, each independently, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, having a carbon number of 7
An aralkyl group of 10 to 10, an alkoxy group having 1 to 8 carbon atoms,
An amide group having 1 to 8 carbon atoms, a ureido group having 1 to 8 carbon atoms,
Represents a carbamoyl group having 1 to 8 carbon atoms, an alkylthio group having 1 to 8 carbon atoms, or an unsubstituted or an amino group having 1 to 8 carbon atoms.

(4) Compound (dye) contained in recording layer
Is an oxonol compound represented by the following general formula (II-1), general formula (II-2), general formula (II-3), and / or general formula (II-4).

[0020]

Embedded image

[0021]

Embedded image

Wherein A ³ , A ⁴ , B ³ and B ⁴ each independently represent a linear, branched or cyclic C 1 -C 18
Alkyl group, alkenyl group having 2 to 18 carbon atoms, alkynyl group having 2 to 18 carbon atoms, aryl group having 6 to 18 carbon atoms, aralkyl group having 7 to 18 carbon atoms, acyl group having 2 to 18 carbon atoms, carbon group An alkyl or aryl sulfonyl group having 1 to 18 carbon atoms, an alkyl sulfinyl group having 1 to 18 carbon atoms,
An alkoxycarbonyl group having 6 to 18 carbon atoms, 7 to 7 carbon atoms
18 aryloxycarbonyl groups, C1-C18 alkoxy groups, C6-C18 aryloxy groups, C1-C18 alkylthio groups, C6-C18 arylthio groups, C2-C18 Acyloxy group, amide group having 1 to 18 carbon atoms, ureido group having 1 to 18 carbon atoms, sulfonyloxy group, carbamoyloxy group, amino group,
Carbamoyl group, sulfamoyl group, halogen atom, hydroxyl group, nitro group, cyano group, carboxyl group,
And one substituent selected from the group consisting of a 4- to 7-membered heterocyclic group (these substituents are further represented by A ³ , A
⁴ , may be substituted with at least one group selected from the group consisting of substituents represented by B ³ and B ⁴ );
² and Z ² each independently represent an atomic group necessary for forming a 4- to 7-membered carbon ring or a 4- to 7-membered heterocyclic ring (these rings are further represented by A ³ , A ⁴ , It may be substituted with at least one group selected from the group consisting of the substituents represented by B ³ and B ⁴ , and is condensed with a 4- to 7-membered carbon ring or a 4- to 7-membered heterocyclic ring. Or L)
⁶ , L ⁷ , L ⁸ , L ⁹ and L ¹⁰ are each independently the above-mentioned A
Represents a methine group which may be substituted with one or two groups selected from the group consisting of substituents represented by ³ , A ⁴ , B ³ and B ⁴ , wherein m 1 and n 1 are independently 0, 1 Or 2 and k1 represents an integer required to neutralize the counter cation; R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ ,
R ²⁷ and R ²⁸ each independently represent a hydrogen atom or the above-mentioned A
Represents one group selected from the group consisting of substituents represented by ³ , A ⁴ , B ³ and B ⁴ (provided that R ²¹ and R ²² , R ²³ and R ²⁴ , R ²⁵ and R ²⁶ and R ²⁷ And R ²⁸ may be linked together to form a heterocyclic ring with a nitrogen atom), R ²⁹ , R ³⁰ , R
³¹ , R ³² and R ³³ each independently represent A ³ , A ⁴ , B
Represents ³ and one group selected from the group consisting of substituents represented by B ^4, p1 is 1 or 2 and q1 and r1 each independently represent an integer of 0-4]

(5) In the compound (dye) of the above (4), R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ are each independently a hydrogen atom, A halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms,
An alkynyl group having 2 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or
8 represents an alkoxy group. (6) In the compound (dye) of the above (4), R ²¹ and R ^21
22 , R ²³ and R ²⁴ , R ²⁵ and R ²⁶ , and R ²⁷ and R ²⁸ are each linked to form a heterocyclic ring having 4 to 7 members (more preferably 5 to 6 members). It is a substituted heterocycle. (7) In the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4), both m and n are 1 or m is 0 n is 2, or m is 2 and n is 0
Is either. (8) In the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4), X ¹ is
= Is O, X ² is an -O. (9) A reflective layer is further provided on the recording layer. (10) In the above (8), a protective layer is further provided on the reflective layer.

(11) The general formula (II-1) and the general formula (II-
2) In the general formula (II-3) or (II-4), whether m1 and n1 are both 1, m1 is 0 and n1 is 2, or m1 is 2 and n1 is 0. Either. (12) In the general formula (II-3) or the general formula (II-4), the carbon rings formed by Y ² and Z ² are each independently:
It is one carbon ring selected from the group consisting of A-1, A-4, A-6, and A-7 below.

[0025]

Embedded image

(13) In the general formula (II-3) or (II-4), the heterocyclic rings formed by Y ² and Z ² each independently represent the following A-8, A-9, A-9 -10, A
-12, A-13, A-16, A-36, A-39, and A-41.

[0027]

Embedded image

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION In the information recording medium of the present invention, the recording layer has the following general formula (I-1), general formula (I-2), general formula (I-3) and / or general formula (I-3). -4).

[0029]

Embedded image

[0030]

Embedded image

The dyes used in the present invention will be described below. The dye used in the present invention is composed of an anionic component (simply an anion portion) and a cationic component (simply a cation portion) which are dye components. First, the anion portion (dye component) will be described in detail. In the above equation,
As the substituent represented by A ¹ , A ² , B ¹ and B ² ,
For example, the following can be mentioned. 1 to 1 carbon atoms
8 (preferably 1 to 8 carbon atoms) substituted or unsubstituted, linear, branched or cyclic alkyl group (eg, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl) -Butyl, cyclohexyl, methoxyethyl, ethoxycarbonylethyl, cyanoethyl, diethylaminoethyl, hydroxyethyl,
Chloroethyl, acetoxyethyl, trifluoromethyl and the like); an alkenyl group having 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) (eg, vinyl and the like); and an alkenyl group having 2 to 18 carbon atoms (preferably 2 to 8 carbon atoms) An alkynyl group (eg, ethynyl and the like); a substituted or unsubstituted aryl group having 6 to 18 (preferably 6 to 10) carbon atoms (eg, phenyl, 4-
Methyl phenol, 4-methoxyphenyl, 4-carboxyphenyl, 3,5-dicarboxyphenyl and the like; a substituted or unsubstituted aralkyl group having 7 to 18 carbon atoms (preferably 7 to 12 carbon atoms) (eg, benzyl, carboxy, etc.) Benzyl and the like);

Having 2 to 18 carbon atoms (preferably having 2 to 2 carbon atoms)
8) a substituted or unsubstituted acyl group (eg, acetyl,
Propionyl, butanoyl, chloroacetyl, etc.); a substituted or unsubstituted alkyl or arylsulfonyl group having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms) (eg, methanesulfonyl, p-toluenesulfonyl, etc.); To 18 (preferably 1 to 8 carbon atoms) alkylsulfinyl group (eg, methanesulfinyl, ethanesulfinyl, octanesulfinyl and the like); and an alkoxycarbonyl group having 2 to 18 (preferably 2 to 8 carbon atoms) (eg,
Methoxycarbonyl, ethoxycarbonyl, etc.); an aryloxycarbonyl group having 7 to 18 (preferably 7 to 12) carbon atoms (eg, phenoxycarbonyl, 4-methylphenoxycarbonyl, 4-methoxyphenylcarbonyl, etc.); -18 (preferably 1-8 carbon atoms)
A substituted or unsubstituted alkoxy group (eg, methoxy,
Ethoxy, n-butoxy, methoxyethoxy and the like); a substituted or unsubstituted aryloxy group having 6 to 18 carbon atoms (preferably 6 to 10 carbon atoms) (eg, phenoxy, 4-methoxyphenoxy and the like); An alkylthio group having 18 (preferably having 1 to 8 carbon atoms) (eg, methylthio, ethylthio, etc.);
8) arylthio group (eg, phenylthio and the like);

C2 to C18 (preferably C2 to C2
8) a substituted or unsubstituted acyloxy group (eg, acetoxy, ethylcarbonyloxy, cyclohexylcarbonyloxy, benzoyloxy, chloroacetyloxy, etc.); substituted or unsubstituted having 1 to 18 carbon atoms (preferably 1 to 8 carbon atoms) A substituted sulfonyloxy group (eg, methanesulfonyloxy, etc.); a substituted or unsubstituted carbamoyloxy group having 2 to 18 (preferably 2 to 8 carbon atoms) (eg, methylcarbamoyloxy, diethylcarbamoyloxy, etc.); Unsubstituted amino group or C1
To 18 (preferably 1 to 8 carbon atoms) substituted amino group (eg, methylamino, dimethylamino, diethylamino, anilino, methoxyphenylamino, chlorophenylamino, pyridylamino, methoxycarbonylamino, n-butoxycarbonylamino, phenoxycarbonylamino , Methylcarbamoylamino, phenylcarbamoylamino, ethylthiocarbamoylamino, methylsulfamoylamino, phenylsulfamoylamino, acetylamino, ethylcarbonylamino, ethylthiocarbonylamino, cyclohexylcarbonylamino, benzoylamino, chloroacetylamino, methane Sulfonylamino, benzenesulfonylamino, etc.);

C 1-18 (preferably C 1-18)
8) amide group (eg, acetamido, acetylmethylamide, acetyloctylamide, etc.);
(Preferably 1 to 8 carbon atoms) a substituted or unsubstituted ureido group (eg, unsubstituted ureido, methyl ureide, ethyl ureide, dimethyl ureide, etc.);
(Preferably having 1 to 8 carbon atoms) a substituted or unsubstituted carbamoyl group (eg, unsubstituted carbamoyl, methylcarbamoyl, ethylcarbamoyl, n-butylcarbamoyl, t-butylcarbamoyl, dimethylcarbamoyl,
Morpholinocarbamoyl, pyrrolidinocarbamoyl, etc.); unsubstituted sulfamoyl group or having 1 to 1 carbon atoms
8 (preferably 1 to 8 carbon atoms) substituted sulfamoyl group (eg, methylsulfamoyl, phenylsulfamoyl, etc.); halogen atom (eg, fluorine, chlorine, bromine, etc.); hydroxyl group; nitro group; Carboxyl group; heterocyclic group (eg, oxazole ring, benzoxazole ring, thiazole ring, benzothiazole ring, imidazole ring, benzimidazole ring, indolenine ring, pyridine ring, morpholine ring, piperidine ring, pyrrolidine ring, sulfolane ring, furan Ring, thiophene ring, pyrazole ring, pyrrole ring, chroman ring, coumarin ring, etc.).

The substituents represented by A ¹ and A ² preferably have a Hammett's substituent constant (σp) value of 0.2 or more. Hammett's substituent constant is, for example, Che
m. Rev .. 91, 165 (1991). Particularly preferred substituents are cyano, nitro, alkoxycarbonyl, acyl, carbamoyl, sulfamoyl, alkylsulfonyl and arylsulfonyl groups.

The substituent represented by B ¹ and B ² is preferably an alkyl group, an aryl group, an alkoxy group, or an amino group.

[-C (= L ¹ )-(E) bonded to Y ^{1
x -C (= X 1) -} ] (. hereinafter, for convenience, referred to as W1) and binds to ^{Z 1 [-C (-L 5)} = (G) y
^{= C (-X 2 -) -} ] ( hereinafter, for convenience, referred to as W2) for in each conjugate state and, carbocyclic or heterocyclic ring formed by the Y ¹ and W1, and Z ¹ and W2 The carbocyclic or heterocyclic ring formed by is considered as one of the resonance structures. Said Y ¹ and W1, and Z ¹ and W
The carbocyclic or heterocyclic ring formed with 2 is preferably a 4- to 7-membered ring, particularly preferably a 5- or 6-membered ring. These rings may further form a condensed ring with another 4- to 7-membered ring. These may have a substituent. Examples of the substituent include those described above as the substituents represented by A ¹ , A ² , B ¹ and B ² . Preferred as hetero atoms forming the heterocyclic ring are B, N, O, S, Se, and Te. Particularly preferred are N, O and S. x and y are each independently 0 or 1, and preferably both are 0.

X ¹ is ＝ O, ＮＲNR or ＣC (CN) ₂
Represents X ² is —O, —NR or —C (CN) ₂
Represents R represents a substituent. Examples of the substituent represented by R include those described above as the substituents represented by A ¹ , A ² , B ¹ and B ² . R is preferably an aryl group. Particularly preferred is phenyl. In the present invention, X ¹ is preferably ＝ O, and X ² is preferably —O.

Examples of the carbon ring formed by Y ¹ and W 1 and Z ¹ and W 2 include the following. In the examples, Ra and Rb each independently represent a hydrogen atom or a substituent.

[0040]

Embedded image

Preferred carbocycles are A-1, A-4, A-
6 and A-7. Particularly preferred is a carbocycle represented by A-1.

Examples of the heterocyclic ring formed by Y ¹ and W 1 and Z ¹ and W 2 include the following. In the examples, Ra, Rb and Rc each independently represent a hydrogen atom or a substituent.

[0043]

Embedded image

[0044]

Embedded image

[0045]

Embedded image

[0046]

Embedded image

[0047]

Embedded image

[0048]

Embedded image

Preferred heterocycles are A-8, A-9, A-
10, A-12, A-13, A-16, A-36, A-
39 and a heterocycle represented by A-41. Particularly preferably, A-8, A-9, A-10, A-13, A-36
And heterocycles represented by A-41. Most preferred are the heterocycles represented by A-9 and A-10.

The substituents represented by Ra, Rb and Rc are:
Each has the same meaning as the substituents represented by A ¹ , A ² , B ¹ and B ² . Ra, Rb and Rc may be mutually linked to form a carbocyclic or heterocyclic ring. Examples of the carbocycle include a saturated or unsaturated 4- to 7-membered carbocycle such as a cyclohexyl ring, a cyclopentyl ring, a cyclohexene ring, and a benzene ring. Examples of the heterocycle include a saturated or unsaturated 4- to 7-membered heterocycle such as a piperidine ring, a piperazine ring, a morpholine ring, a tetrahydrofuran ring, a furan ring, a thiophene ring, a pyridine ring, and a pyrazine ring. it can. These carbocycles or heterocycles may be further substituted. Further substitutable groups include
It has the same meaning as the substituents represented by A ¹ , A ² , B ¹ , and B ² .

The methine groups represented by L ¹ , L ² , L ³ , L ⁴ and L ⁵ are each independently a methine group which may have a substituent. Examples of the substituent include those described above as the substituents represented by A ¹ , A ² , B ¹ and B ² . Preferred substituents are an alkyl group,
Aralkyl, aryl, alkoxy, aryloxy, alkylthio, arylthio, halogen, amino, carbamoyl and heterocyclic groups. The substituents are linked to form a 5- to 7-membered ring (eg, a cyclopentene ring, a 1-dimethylaminocyclopentene ring, a 1-diphenylaminocyclopentene ring, a cyclohexene ring,
Chlorocyclohexene ring, isophorone ring, 1-morpholinocyclopentene ring, cycloheptene ring). Preferably, m and n are both 1, m is 0 and n is 2, or m is 2 and n is 0. k represents an integer required to neutralize the counter cation.

Next, the cation portion will be described in detail. R
¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a hydrogen atom or a substituent. Also R ¹ and R
² , R ³ and R ⁴ , R ⁵ and R ^6, and R ⁷ and R ⁸ may be linked together to form a heterocyclic ring with a nitrogen atom. R ⁹ , R
¹⁰ , R ¹¹ , R ¹² and R ¹³ represent a substituent. p represents 1 or 2, and q and r each independently represent an integer of 0 to 4.

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R
Examples of the substituent represented by ⁷ and R ⁸ include, for example, an anion moiety in the general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-4). In the description, the same substituents as those represented by A ¹ , A ² , B ¹ and B ² can be mentioned. Preferred examples of the substituent represented by R ^{1 to} R ⁸ include a hydrogen atom, a halogen atom (eg, F, C, 1, Br), an alkyl group having 1 to 8 carbon atoms (eg, methyl, ethyl, Propyl, isopropyl,
n-butyl, isobutyl, sec-butyl, t-butyl, pentyl, hexyl, heptyl, octyl), alkenyl group having 2 to 8 carbon atoms (eg, vinyl, allyl, 2-methylbutenyl), alkynyl having 2 to 8 carbon atoms Group (eg, ethynyl), an aryl group having 6 to 10 carbon atoms (eg, phenyl), an aralkyl group having 7 to 10 carbon atoms (eg, benzyl), and an alkoxy group having 1 to 8 carbon atoms (eg, methoxy, ethoxy) ). The above R ^{1 to} R ⁸
The substituent represented by is particularly preferably an unsubstituted alkyl group having 1 to 6 carbon atoms.

The above groups may be further substituted, if possible. Examples of the substituent include a hydroxy group, a halogen atom (eg, F, C, 1, Br, etc.), 6 to 10 aryl groups (eg, phenyl), 1 to 1 carbon atoms
8 alkoxy groups (eg, methoxy, ethoxy), C6-10 aryloxy groups (eg, phenoxy), C1-8 alkylthio groups (eg, methylthio, ethylthio), C6-10 arylthio groups Group (eg, phenylthio), unsubstituted amino group, C1-C8 amino group (eg, methylamino, dimethylamino), C1-C8
A carbonamide group (methylcarbonylamide), a C1-8 sulfonamide group (eg, methanesulfonamide), a C1-8 acyl group (eg, acetyl, butanoyl), a C2-8 alkoxy Carbonyl group (eg,
Methoxycarbonyl), and a carbamoyl group having 1 to 8 carbon atoms (eg, carbamoyl).

The heterocyclic ring formed by linking R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ , and R ⁷ and R ⁸ together with a nitrogen atom is a 4- to 7-membered unsubstituted heterocyclic ring. It is preferably a ring. More preferably, it is a 5- to 6-membered unsubstituted heterocycle. Examples of preferred heterocycles include a pyrrolidine ring, a piperidine ring, and a morpholine ring. Particularly preferred is a piperidine ring.

The substituents represented by R ⁹ , R ¹⁰ , R ¹¹ , R ¹² and R ¹³ are the same as the specific examples of the substituents represented by A ¹ , A ² , B ¹ and B ^2. Can be mentioned. Preferred examples of the substituent represented by R ^{9 to} R ¹³ include a halogen atom, an alkyl group having 1 to 8 carbon atoms, and a 2 to 8 carbon atoms.
Alkenyl group, alkynyl group having 2 to 8 carbon atoms, aryl group having 6 to 10 carbon atoms, aralkyl group having 7 to 10 carbon atoms, alkoxy group having 1 to 8 carbon atoms, amide group having 1 to 8 carbon atoms, carbon atom Examples thereof include a ureido group having 1 to 8 carbon atoms, a carbamoyl group having 1 to 8 carbon atoms, an alkylthio group having 1 to 8 carbon atoms, or an unsubstituted or an amino group having 1 to 8 carbon atoms. The substituent represented by R ^{9 to} R ¹² has 1 to 8 carbon atoms.
An alkyl group (eg, methyl, ethyl), an alkoxy group having 1 to 8 carbon atoms (eg, methoxy), a ureido group having 1 to 8 carbon atoms (eg, ureido, methylureide), or unsubstituted or 1 to 1 carbon atoms More preferably, it is 8 amino groups (eg, dimethylamino). The substituent represented by R ¹³ is a halogen atom (eg, F or Cl), an alkyl group having 1 to 8 carbon atoms (eg, methyl or ethyl), or an alkoxy group having 1 to 8 carbon atoms (eg, methoxy). An amide group having 1 to 8 carbon atoms (eg, acetamido), a ureido group having 1 to 8 carbon atoms (eg, ureido), a carbamoyl group having 1 to 8 carbon atoms (eg, carbamoyl), or a carbamoyl group having 1 to 8 carbon atoms More preferably, it is an alkylthio group (eg, methylthio). q
And r are each preferably 0 to 2, and particularly preferably 0. p is preferably 1.

The formulas (II-1) to (II-)
In the oxonol compound represented by 4), the designation in the anion part thereof is A ³ , A ⁴ , B ³ and B ⁴ , Y ²
And Z ² , L ⁶ , L ⁷ , L ⁸ , L ⁹ and L ¹⁰ , m1 and n1, and k1, and their designations in the cation moiety: R ^{21 to} R ³³ , and p1, q1 and r1 are respectively as described above. Representation in the anion part of the general formulas (I-1) to (I-4): A ¹ , A ² , B ¹ and B ² , Y
¹ and Z ¹ , L ¹ , L ² , L ³ , L ⁴ and L ⁵ , m and n, and k, and their designation in the cation part: R
^{1 to} R ¹³ , p, q, and r have the same meanings, and the preferred ranges for each are also the same.

The general formula (I-1), the general formula (I-2), the general formula (I-3) or the general formula (I-I) used in the present invention.
Specific examples of the anion part (C) and the cation part (D) of the compound (dye) represented by 4) are described below.

[0059]

Embedded image

[0060]

Embedded image

[0061]

Embedded image

[0062]

Embedded image

[0063]

Embedded image

[0064]

Embedded image

[0065]

Embedded image

[0066]

Embedded image

[0067]

Embedded image

[0068]

Embedded image

[0069]

Embedded image

[0070]

Embedded image

[0071]

Embedded image

[0072]

Embedded image

[0073]

Embedded image

[0074]

Embedded image

[0075]

Embedded image

[0076]

Embedded image

[0077]

Embedded image

[0078]

Embedded image

[0079]

Embedded image

[0080]

Embedded image

[0081]

Embedded image

[0082]

Embedded image

[0083]

Embedded image

[0084]

Embedded image

[0085]

Embedded image

[0086]

Embedded image

[0087]

Embedded image

[0088]

Embedded image

[0089]

Embedded image

[0090]

Embedded image

[0091]

Embedded image

[0092]

Embedded image

[0093]

Embedded image

[0094]

Embedded image

[0095]

Embedded image

[0096]

Embedded image

[0097]

Embedded image

[0098]

Embedded image

[0099]

Embedded image

The preferred specific compounds (dyes) used in the present invention are shown in Table 1 below. In Table 1, examples of the compound (dye) include an anion part (C) and a cation part (D).
Are combined. Hereinafter, an example of compound 1 (dye 1) will be described. Compound 1 [anion part (C-1) / cation part (D-
5)] is represented by the following formula. In addition,
The same applies to compound examples after compound 2.

[0101]

Embedded image

[0102]

[Table 1] (Part 1)． Compound Compound No. Anion part Cation part No. Anion part Cation part ──────────────────────────────────── 1 C-1 D- 52 C- 1 D-383 C-1 D-514 C-6 D-79 5 C-6 D-26 C-6 D-227 C-6 D-518 C-14 D-59 C-14 D-59 10 C-21 D-511 C-21 D-912 C-34 D-15 13 C-34 D-5114 C-34 D-71 15 C-47 D-116 C-47 D -30 17 C-47 D-49 18 C-63 D-519 C-63 D-5120 C-77 D-521 C-77 D-5122 C-77 D-7923 C-86 D- 3924 C-86 D-46 25 C-86 D-49 26 C-101 D-527 C-101 D-512 8 C-101 D-78 29 C-117 D-530 C-117 D-51 ───────────────────────────── ───────

[0103]

Table 1 (Part 2) ──────────────────────────────────── Compound Compound No. Anion part Cation part No. Anion part Cation part ３１ 31 C-117 D-79 32 C- 122 D-5133 C-122 D-68 34 C-122 D-79 35 C-127 D-5136 C-127 D-62 37 C-143 D-538 C-143 D-19 39 C-143 D-5140 C-147 D-541 C-147 D-51 42 C-148 D-543 C-148 D-5144 C-148 D-7945 C-153 D-546 C-153 D -51 47 C-153 D-79 48 C-154 D-51 49 C-157 D-79 50 C-164 D-33 51 C-171 D-49 52 C-171 D-59 53 C-171 D- 79 54 C-174 D-35 C-174 D-36 56 C-174 D-51 57 C-180 D-51 58 C-180 D-79 59 C-182 D-51 60 C-182 D-79 61 C-194 D-12 62 C -194 D-32 63 C-208 D-29 64 C-208 D-64 ─────────────────────────────── ─────

The compounds (dyes) represented by the general formulas (I-1), (I-2), (I-3) and (I-4) according to the present invention are as follows: General formula (III-1)
And a non-dissociated form of a compound (dye) represented by (III-2) or an alkali metal salt (eg, Li salt, Na salt, K
Salt), an ammonium salt (NH ⁴⁺ salt), or a triethylammonium salt (Et ₃ NH ⁺ salt), and a salt compound represented by the following general formulas (IV-1) and (IV-2). It can be easily synthesized by a salt exchange reaction with an onium salt in water or an organic solvent (methanol, ethanol, isopropanol, dimethylformamide, etc.).

[0105]

Embedded image

Wherein A ⁵ and A ⁶ , B ⁵ and B ⁶ , Y ³
And Z ³ , and L ¹¹ , L ¹² , L ¹³ , L ¹⁴ and L ¹⁵ , X
³ and X ⁴ , E1 and G1, m2 and n2, and x
1 and y1 are respectively the general formula (I-1) described above,
Formula (I-2), Formula (I-3) or Formula (I
A ¹ , A ² , B ¹ and B ² , Y ¹ and Z in -4)
^{1, L 1, L 2,} L 3, L 4 and L ^5, X ¹ and X ^2,
It has the same meaning as E and G, m and n, and x and y, respectively.

[0107]

Embedded image

In the formula, R ^{41 to} R ⁵³ , and p2, q2 and r2 represent the above-mentioned general formulas (I-1) to (I-
R ¹ to R ¹³ of 4), and a p, respectively and the q and r synonymous. M ^k2- and M ^k3- each represent an anion, and k2 and k3 are one or more (preferably 1 to 8, more preferably 1 to 6, particularly 1 to 4) necessary for neutralizing the counter cation. Represents an integer. As the anion, for example,
Halide ions (Cl ⁻ , Br ⁻ , I ⁻ ), sulfonate ions (CH ₃ SO ₃ ⁻ , p-toluenesulfonate ion, naphthalene-1,5-disulfonate ion),
ClO ₄ ⁻ , BF ₄ ⁻ , and PF ₆ ⁻ can be exemplified.

Incidentally, the general formula (III-1) and the general formula (II
The compound represented by I-2) generally has a methine group or a polymethine group in a corresponding active methylene compound (eg, pyrazolone, thiobarbituric acid, barbituric acid, indandione, hydroxyphenaleonone) and a methine dye. It can be synthesized by a condensation reaction with a methine source for introduction. Details of the synthesis of this type of compound are described in JP-B-39-22069 and JP-B-43-3504.
Nos. 52-38056, 54-38129, 55
Nos. 10059 and 58-35544;
Nos. 99620, 52-92716, 59-168
No. 34, No. 63-316853, and No. 64-408
No. 27, each of which includes British Patent No. 11333986, U.S. Pat. Nos. 3,247,127, 4042397, and 4
Nos. 1813225, 5213956, and 526
No. 0179 can be referred to.

Specifically, for introducing a monomethine group, orthoesters such as ethyl orthoformate and ethyl orthoacetate or N, N-diphenylformamidine hydrochloride are used. For introducing a trimethine chain, trimethoxypropene is used. ,
1,1,3,3-tetramethoxypropane or malonaldehyde dianyl hydrochloride (or derivatives thereof)
Glutaconaldehyde dianyl hydrochloride or 1- (2,4-dinitrophenyl) -pyridinium chloride (or a derivative thereof) is used to introduce a pentamethine chain.

The compounds represented by the general formulas (IV-1) and (IV-
The compound represented by 2) is disclosed in US Pat. No. 3,251,881.
No. 3,575,871 and No. 3,484,467, and the method described in JP-A-61-69991 can be easily synthesized.

The following formulas (I-1) and (I-
2) and synthesis examples of the compounds represented by formulas (I-3) and (I-4) will be described.

(Synthesis Example 1) Compound 4 (anion part: C-6, cation part: D-7)
Synthesis of 9) 0.27 g of the following compound a was added to 10 mL of dimethylformamide (DMF) at room temperature and stirred. To this solution, 1.2 mL of tributylamine was added dropwise, and after stirring for 30 minutes, 0.30 g of the following compound b was added. After stirring at the same temperature for 2 hours, 60 mL of methanol was added, washed with methanol, and dried to obtain 0.29 g of the desired product.
λmax (maximum absorption wavelength, the same applies hereinafter) = 607 nm (in methanol).

[0114]

Embedded image

[0115]

Embedded image

(Synthesis Example 2) Compound 7 (anion part: C-6, cation part: D-5)
Synthesis of 1) In Synthesis Example 1, the following compound c was used instead of compound b.
Except that 0.28 g was used, the same procedure was repeated to obtain the target substance 0.1.
3 g were obtained. .lambda.max = 607 nm (in methanol).

[0117]

Embedded image

Synthesis Example 3 Compound 13 (anion part: C-34, cation part: D-
Synthesis of 51) In Synthesis Example 1, the following compound d was used instead of compound a
Except that 0.30 g was used, the same procedure was repeated to obtain the target substance.
25 g were obtained. .lambda.max = 581 nm (in methanol).

[0119]

Embedded image

(Synthesis Example 4) Compound 17 (anion part: C-47, cation part: D-
Synthesis of 49) The following compound e (0.55 g) was dissolved in DMF (10 mL),
0.2 mL of triethylamine was added dropwise. Further, 0.50 g of the following compound f was added to this solution, and the mixture was stirred at room temperature for 1 hour. Thereafter, 70 mL of methanol was added, and the precipitated crystals were filtered, washed with methanol, and dried to obtain 0.4 g of the desired product. .lambda.max = 607 nm (in methanol).

[0121]

Embedded image

[0122]

Embedded image

(Synthesis Example 5) Compound 25 (anion: C-86, cation: D-
Synthesis of 49) 1.0 g of the following compound g was added to 30 mL of methanol, and 0.1 mL of 25% aqueous ammonia was added dropwise at room temperature with stirring. Into this solution, 0.9 g of the compound f was added with DMF1
A solution dissolved in 0 mL was added, and stirring was continued for 2 hours. The precipitated crystals were filtered, washed with methanol, and dried to obtain 0.89 g of the desired product. λmax = 637 nm
(In methanol).

[0124]

Embedded image

(Synthesis Example 6) Compound 34 (anion part: C-122, cation part: D
Synthesis of -79) The following compound h (0.70 g) was dissolved in DMF (10 mL),
2 mL of triethylamine was added dropwise. 0.75 g of the compound b used above was added to this solution, and the mixture was stirred at room temperature for 1 hour, and then 40 mL of methanol was added. The precipitated crystals were filtered, washed with methanol, and dried to obtain 1.12 of the desired product
g was obtained. .lambda.max = 652 nm (in methanol).

[0126]

Embedded image

(Synthesis Example 7) Compound 44 (anion part: C-148, cation part: D
Synthesis of -79) The following compound i (0.25 g) was dissolved in DMF (10 mL),
1 mL of triethylamine was added dropwise. 0.27 g of the compound b used above was added to this solution, and the mixture was stirred at room temperature for 1 hour, and then 40 mL of methanol was added. The precipitated crystals were collected by filtration, washed with methanol and dried to give the desired product 0.22
g was obtained. .lambda.max = 642 nm (in DMF).

[0128]

Embedded image

(Synthesis Example 8) Compound 46 (anion part: C-153, cation part: D
Synthesis of -51) 0.25 g of the following compound j was added to 10 mL of DMF, and 1 mL of triethylamine was added dropwise at room temperature with stirring.
0.23 g of the compound c used above was added to this solution,
After continuing stirring for 2 hours, 30 mL of methanol was added. The precipitated crystals were filtered, washed with methanol and dried to obtain 0.28 g of the desired product. λmax = 622 nm
(In DMF).

[0130]

Embedded image

(Synthesis Examples 9 to 11) Compounds 53, 59 and 62 were synthesized in the same manner as in Synthesis Example 7. The maximum absorption wavelength of the synthesized compound in methanol is shown below. Compound 53: λmax = 672 (nm) Compound 59: λmax = 642 (nm) Compound 62: λmax = 603 (nm)

The compounds represented by the general formulas (I-1), (I-2), (I-3) and (I-4) according to the present invention can be used alone. Or two or more of them may be used in combination. In addition, the general formula (I-
Compounds represented by 1), general formula (I-2), general formula (I-3) or general formula (I-4) may be used in combination. Alternatively, the compound according to the present invention may be used in combination with a compound other than those conventionally known as dyes for information recording media. Examples of these include oxonol-based dyes, cyanine-based dyes, phthalocyanine-based dyes, pyrylium / thiopyrylium-based dyes, azurenium-based dyes, squalilium-based dyes, naphthoquinone-based dyes, and triphenylmethane-based dyes other than those used in the present invention. Dyes and triallylmethane dyes can be mentioned.

The information recording medium of the present invention has the general formula (I)
-1), a recording layer containing a compound (dye) represented by general formula (I-2), general formula (I-3) and / or general formula (I-4) provided on a substrate. . The information recording medium of the present invention is a so-called CD-R type information recording medium,
It can be configured as a VD-R type information recording medium. When configured as a CD-R type information recording medium, the general formula (I-) is formed on a disc-shaped transparent substrate on which a pre-groove having a track pitch of 1.4 to 1.6 μm is formed.
1) It is preferable that a recording layer containing a compound represented by the general formula (I-2), the general formula (I-3) and / or the general formula (I-4) is provided. When a DVD-R type information recording medium is configured, a disc-shaped transparent substrate on which a pre-groove having a track pitch of 0.6 to 0.9 μm is formed is provided with the general formula (I-1) and the general formula (I-1). Formula (I-
2) It is preferable that a recording layer containing a compound represented by the general formula (I-3) and / or the general formula (I-4) is provided. In any of the information recording media of the above embodiments, a light reflecting layer is preferably provided on the recording layer, and a protective layer is preferably provided on the light reflecting layer.

It is preferable that the DVD-R type information recording medium is specifically configured in the following two forms. (1) A disc-shaped transparent substrate having a track pitch of 0.6 to 0.9 μm and a thickness of 0.6 ± 0.1 mm on a surface on which the pre-groove is provided, Two sheets provided with a recording layer containing the compound represented by the general formula (I-1), the general formula (I-2), the general formula (I-3) and / or the general formula (I-4) An information recording medium in which a laminate is joined such that each recording layer is on the inside.

(2) Track pitch is 0.6 to 0.9 μm
m pregroove formed, thickness 0.6 ± 0.1
mm on the surface of the disk-shaped transparent substrate on which the pregroove is provided, the general formula (I-1) and the general formula (I-
2) a laminate provided with a recording layer containing a compound represented by the general formula (I-3) and / or the general formula (I-4), and a disc-shaped transparent material having substantially the same diameter as the substrate of the laminate. An information recording medium in which a substrate and a substrate are joined such that each recording layer is on the inside. In the information recording medium of the above-described embodiment, it is preferable that a reflective layer is further provided on the recording layer, and a protective layer is further provided on the reflective layer. The information recording medium of the present invention, for example,
It can be manufactured by the method described below.

The substrate can be arbitrarily selected from various materials used as a substrate of a conventional information recording medium. As the substrate material, for example, glass; polycarbonate; acrylic resin such as polymethyl methacrylate;
Examples thereof include polyvinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymer; epoxy resins; amorphous polyolefins and polyesters. These may be used in combination, if desired. Note that these materials can be used in the form of a film or a rigid substrate.
Among the above materials, polycarbonate is preferred from the viewpoints of moisture resistance, dimensional stability, cost, and the like. As these materials, materials that can transmit laser light are selected, and the transmittance is preferably 70 to 100%. A CD-R type information recording medium has a thickness of 1.2 mm and a diameter of 120 m.
m and a DVD-R type information recording medium, a 0.6 mm thick and 120 mm diameter transparent substrate or a 0.6 mm thick and 80 mm diameter transparent substrate are used.

An undercoat layer may be provided on the surface of the substrate on which the recording layer is provided, for the purpose of improving flatness, improving adhesive strength, preventing deterioration of the recording layer, and the like. Examples of the material of the undercoat layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, and chlorosulfonation. Polymeric substances such as polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate, etc .; and silane coupling agents And other surface modifiers.
The undercoat layer is formed by dissolving or dispersing the above substances in an appropriate solvent to prepare a coating solution, and then applying the coating solution to the substrate surface by a coating method such as spin coating, dip coating, or extrusion coating. can do. The thickness of the undercoat layer is generally in the range of 0.005 to 20 μm, preferably in the range of 0.01 to 10 μm.

Further, it is preferable that irregularities (pre-grooves) representing information such as tracking grooves or address signals are formed on the substrate (or undercoat layer). This pregroove is preferably formed directly on the substrate when injection molding or extrusion molding of a resin material such as polycarbonate.

The pre-groove may be formed by providing a pre-groove layer. As a material for the pregroove layer, a mixture of at least one monomer (or oligomer) of acrylic acid monoester, diester, triester and tetraester and a photopolymerization initiator can be used. For the formation of the pre-groove layer, for example, first, a mixed solution composed of the above-mentioned acrylate ester and the polymerization initiator was applied on a precisely formed master (stamper), and further, a substrate was placed on this coating solution layer. Thereafter, the coating layer is cured by irradiating ultraviolet rays through the substrate or the matrix to fix the substrate and the coating layer. Next, it can be obtained by peeling the substrate from the matrix. The thickness of the pregroove layer is generally 0.05
１００100 μm, preferably 0.1-50 μm
m.

The depth of the pregroove is 300 to 2000 mm.
And the half-value width is 0.2
It is preferably in the range of 0.9 μm to 0.9 μm. By setting the depth of the pre-groove layer in the range of 1500 to 2000 °, sensitivity can be improved without substantially lowering the reflectance, which is particularly preferable. Accordingly, such an optical disk has high sensitivity, and thus can record even with a low laser power, thereby enabling use of an inexpensive semiconductor laser or extending the service life of the semiconductor laser.

On the surface of the substrate (or undercoat layer) (on the surface of the pre-groove if formed), the above-mentioned general formulas (I-1) to (I- A recording layer containing at least one dye selected from the group consisting of the compounds represented by 4) is provided. The recording layer may contain various compounds known as a singlet oxygen quencher in order to further improve light resistance. As a typical example of the quencher, JP-A-3-224793
, Metal salts represented by the general formulas (III), (IV) and (V), diimmonium salts and aminium salts described in JP-A-2-300287 and JP-A-2-3000028.
No. 8 gazette, etc. can be mentioned.

The recording layer is formed by dissolving the dyes represented by the general formulas (I-1) to (I-4) according to the present invention and, if desired, a quencher or a binder in a solvent. A solution can be prepared by preparing a solution, applying the solution to the substrate surface to form a coating film, and then drying. Solvents for the coating solution for forming the dye recording layer include esters such as butyl acetate 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 formamide; hydrocarbons such as cyclohexane; ethers such as tetrahydrofuran, ethyl ether and dioxane; alcohols such as ethanol, n-propanol, isopropanol, n-butanol and diacetone alcohol; Fluorinated solvents such as tetrafluoropropanol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and propylene glycol monomethyl ether It can be mentioned. The above solvent may be used alone or in combination of two or more in consideration of the solubility of the compound to be used.The coating solution may further contain various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant. You may add according to the objective.

When a binder is used, examples of the binder include natural organic high-molecular substances such as gelatin, cellulose derivatives, dextran, rosin and rubber; and hydrocarbon-based substances such as polyethylene, polypropylene, polystyrene and polyisobutylene. Resins; vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride / polyvinyl acetate copolymer; acrylic resins such as polymethyl acrylate and polymethyl methacrylate; polyvinyl alcohol, chlorinated polyethylene, epoxy resin, Synthetic organic polymers such as butyral resins, rubber derivatives, and initial condensates of thermosetting resins such as phenol / formaldehyde resins can be given. When a binder is used in combination as a material for the recording layer, the amount of the binder used is generally 10 parts by weight or less, preferably 5 parts by weight or less based on 1 part by weight of the dye. The concentration of the coating solution thus prepared is generally in the range of 0.01 to 10% by weight, preferably 0.1 to 10% by weight.
It is in the range of 1-5% by weight.

Examples of the coating method include a spray method, a spin coating method, a dipping method, a roll coating method, a blade coating method, a doctor roll method, and a screen printing method. The recording layer may be a single layer or a multilayer. The thickness of the recording layer is generally in the range from 20 to 500 nm, preferably in the range from 50 to 300 nm. The recording layer may be provided not only on one side of the substrate but also on both sides.

On the recording layer, a reflection layer is provided for the purpose of improving the reflectance at the time of reproducing information. The light-reflective substance that is the material of the reflection layer is a substance having a high reflectance with respect to laser light, and examples thereof include Mg, Se, Y, and T.
i, Zr, Hf, V, Nb, Ta, Cr, Mo, W, M
n, Re, Fe, Co, Ni, Ru, Rh, Pd, I
r, Pt, Cu, Ag, Au, Zn, Cd, Al, G
a, In, Si, Ge, Te, Pb, Po, Sn, Bi
Metal and semimetal or stainless steel. Of these, preferred are Cr, N
i, Pt, Cu, Ag, Au, Al and stainless steel. These substances may be used alone, or in combination of two or more kinds, or as an alloy. The reflective layer can be formed on the recording layer by, for example, vapor deposition, sputtering, or ion plating of the above-mentioned reflective substance. The thickness of the reflective layer is generally in the range of 10 to 300 nm, preferably 50 to 300 nm.
The range is 200 nm.

It is preferable that a protective layer is provided on the reflective layer for the purpose of physically and chemically protecting the recording layer and the like. This protective layer may be provided on the side of the substrate where the recording layer is not provided for the purpose of enhancing the scratch resistance and the moisture resistance. As a material used for the protective layer, for example, S
Examples thereof include inorganic substances such as iO, SiO ₂ , MgF ₂ , SnO ₂ , and Si ₃ N _4; and organic substances such as a thermoplastic resin, a thermosetting resin, and a UV-curable resin.

The protective layer can be formed, for example, by laminating a film obtained by extrusion of a plastic on an adhesive layer and / or on a substrate. Alternatively, it may be provided by a method such as vacuum deposition, sputtering, or coating. In the case of a thermoplastic resin or a thermosetting resin, it can also be formed by dissolving in an appropriate solvent to prepare a coating solution, applying the coating solution, and drying. In the case of a UV-curable resin, it can also be formed by preparing a coating solution as it is or by dissolving it in an appropriate solvent, applying the coating solution, and irradiating with UV light to cure. These coating solutions further contain an antistatic agent, antioxidant, UV
Various additives such as an absorbent may be added according to the purpose.
The thickness of the protective layer is generally in the range from 0.1 to 100 μm.

The information recording medium of the present invention may be a single plate having the above-described configuration, or two substrates having the above-mentioned configuration may be faced to each other such that the recording layer is on the inside, and an adhesive or the like may be used. By using the bonding method, a bonding type recording medium can be manufactured. Alternatively, an air sandwich type recording medium is manufactured by bonding a substrate having the above configuration to at least one of two disk-shaped substrates via a ring-shaped inner spacer and a ring-shaped outer spacer. be able to.

The C of the present invention which can be produced by the method as described above
Since the DR type information recording medium has a high reflectance of about 70%, it can be reproduced by a commercially available CD player. Therefore, an optical disk having high reflectance and excellent light resistance can be obtained.

Further, the two laminates, each having a recording layer, a reflective layer, and, if desired, a protective layer provided on the substrate, produced as described above, were bonded with an adhesive so that each recording layer was on the inside. By bonding, a DV with two recording layers
A DR information recording medium can be manufactured. Further, by bonding one laminated body obtained as described above and a disc-shaped protective substrate having a diameter substantially the same as that of the substrate of the laminated body with an adhesive such that the recording layer is on the inside, one side is obtained. A DVD-R type information recording medium having only a recording layer can be manufactured.

The information recording method is performed, for example, as follows using the information recording medium of the present invention. First, the information recording medium is set to a predetermined constant linear speed (1.
(2 to 14 m / sec) or a predetermined constant angular velocity while irradiating recording light such as semiconductor laser light from the substrate side. By this light irradiation, the irradiated portion of the recording layer absorbs the light and locally raises the temperature, and physical or chemical changes occur to change its optical characteristics, thereby recording information. . 500 nm to 8 as recording light
A semiconductor laser beam having an oscillation wavelength in the range of 50 nm is used. The wavelength of the laser beam used is preferably in the range from 500 nm to 800 nm. In a CD-R type information recording medium, the wavelength of the laser beam is 750 to 850 nm (more preferably, 770 nm).
To 795 nm, especially 775 to 790 nm). Alternatively, in a DVD-R type information recording medium, the wavelength of a laser beam is 600 to 700 nm.
(More preferably, 620-680 nm, especially 630-680 nm
645 nm). Reproduction of information recorded as described above involves irradiating a semiconductor laser beam having the same wavelength as that at the time of recording from the substrate side while rotating the information recording medium at a predetermined constant linear speed, and detecting the reflected light. Can be performed. It should be noted that the information recording medium of the present invention is capable of recording / reproducing not only 1 × speed in the case of a normal CD format but also 4 × speed or higher.

[0152]

EXAMPLES Examples and comparative examples of the present invention will be described below.

Example 1 20 g of the oxonol dye (compound 4) according to the present invention was dissolved in 100 mL of 2,2,3,3-tetrafluoropropanol to prepare a coating solution for forming a recording layer. A polycarbonate substrate having a spiral pre-groove (track pitch: 1.7 μm, groove width: 0.4 μm, groove depth: 0.16 μm) formed on its surface by injection molding (diameter:
The recording layer was formed by spin-coating on the preblowing surface (120 mm, thickness: 1.2 mm). The thickness of the recording layer was about 140 nm in the pre-groove.

Then, Au was sputtered on the recording layer to form a metal reflection layer having a thickness of about 100 nm. Further, a UV-curable resin (UV-curing agent SD-220, Dainippon Ink and Chemicals, Inc.) was applied on the reflective layer and irradiated with ultraviolet rays to form a protective layer having a thickness of 5 μm. Through the above steps, a CD-R type information recording medium (optical disk) according to the present invention was obtained.

Examples 2 to 10 In the same manner as in Example 1, except that the oxonol dye according to the present invention shown in Table 2 was used in the same amount in place of the oxonol dye (compound 4). Thus, an information recording medium according to the present invention was obtained.

Comparative Example 1 The procedure of Example 1 was repeated, except that the following oxonol dye (Compound 4) was used in place of the oxonol dye (Compound 4), and the following conventionally known cyanine dye (Compound A) was used in the same amount. Similarly, an information recording medium for comparison was obtained.

[0157]

Embedded image

[Comparative Example 2] In Example 1, instead of the oxonol dye (compound 4), a cation moiety was used.
An information recording medium for comparison was obtained in the same manner as in Example 1 except that the same amount of the following oxonol dye (compound B) having an ammonium salt substituted with three ethyl groups was used.

[0159]

Embedded image

[Evaluation of Information Recording Medium] (Evaluation of recording / reproducing characteristics before Xe lamp irradiation (fresh)) Using an OMT2000 (manufactured by Pulstick) evaluator, the obtained optical disk was subjected to a wavelength of 780 nm and a linear velocity of 1. At 2 m / sec, recording was performed while the laser power was varied in the range of 5 to 15 mW. The signal was reproduced at a laser power of 0.5 mW, and the degree of modulation and groove reflectivity at 3T and 11T signals at the optimum power were measured. The standard of the modulation degree of the 3T signal is 0.3 to 0.7, and the standard of the modulation degree of the 11T signal is 0.6 or more. Indicates good. The higher the reflectance, the better the characteristics.

(Evaluation of recording / reproduction characteristics after Xe lamp irradiation) Further, these optical disks were irradiated with a Xe lamp (280,000 lux) for 24 hours (hours), 48 hours, or 72 hours.
Thereafter, the modulation degree and the groove reflectivity of the recording / reproducing signal were examined. Table 2 summarizes the evaluation results obtained as described above.

[0162]

[Table 3]

[0163]

[Table 4]

From the results shown in Table 2, the optical disk according to the present invention having a recording layer containing the dyes represented by the general formulas (I-1) to (I-4) according to the present invention (Examples 1 to 1)
In the case of 0), it can be seen that better recording / reproducing characteristics can be obtained as compared with a comparative optical disk having a recording layer containing an oxonol compound into which a tertiary ammonium salt is introduced (Comparative Example 2). . In addition, the optical disc according to the present invention has lower performance after Xe lamp irradiation than the optical disc of Comparative Example 2 and the comparative optical disc having a recording layer containing a cyanine dye (Comparative Example 1) which has been conventionally known. It can be seen that the light resistance is extremely low, and the light resistance is remarkably improved.

[0165]

By using the dyes represented by formulas (I-1) to (I-4), excellent recording / reproducing characteristics can be obtained, and high stability in light resistance and storage durability can be obtained. An information recording medium can be manufactured. In particular, the novel oxonol compound of the present invention can be advantageously used for producing an information recording medium.

[Procedure amendment]

[Submission date] January 21, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0097

[Correction method] Change

[Correction contents]

[0097]

Embedded image

Claims (11)

[Claims] An information recording medium comprising a substrate and a recording layer on which information can be recorded by a laser beam is provided.
The recording layer has the following general formula (I-1) and general formula (I-
2) An information recording medium comprising a compound represented by formula (I-3) and / or formula (I-4). Embedded image Embedded image [Wherein, A ¹ , A ² , B ¹ and B ² each independently represent a substituent, and Y ¹ and Z ¹ each independently represent an atomic group necessary for forming a carbocyclic or heterocyclic ring. , E and G
Each independently represents an atomic group required to complete a conjugated double bond chain, and X ¹ represents ＝ O, ＮＲNR or ＝ C (C
N) ₂ , wherein X ² is -O, -NR or -C (CN)
₂ (where R represents a substituent), L ¹ , L ² , L
³ , L ⁴ and L ⁵ each independently represent a methine group which may be substituted, m and n each independently represent 0, 1 or 2, x and y each independently represent 0 or 1. And k represents the integer required to neutralize the counter cation;
R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸
Represents a hydrogen atom or a substituent each independently (provided that
R ¹ and R ^2, R ³ and R ^4, R ⁵ and R ⁶ and R ⁷ and R ⁸
May combine to form a heterocyclic ring together with the nitrogen atom), R ⁹ , R ¹⁰ , R ¹¹ , R ¹² and R ¹³ each independently represent a substituent, and p is 1 or 2 And q and r each independently represent an integer of 0-4. 2. R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ ,
R ⁷ and R ⁸ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, and 6 to 10 carbon atoms.
The information recording medium according to claim 1, which represents an aryl group, an aralkyl group having 7 to 10 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms. 3. R ¹ and R ² , R ³ and R ⁴ , R ⁵ and R ⁶ ,
2. The information recording medium according to claim 1, wherein the heterocyclic ring formed together with R ⁷ and R ⁸ together with the nitrogen atom is a 4- to 7-membered unsubstituted heterocyclic ring. 4. The compound contained in the recording layer is represented by the following general formula (II-1), general formula (II-2), general formula (II-3),
The information recording medium according to claim 1, which is an oxonol compound represented by the general formula (II-4). Embedded image Embedded image [Wherein A ³ , A ⁴ , B ³ and B ⁴ are each independently a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, An alkynyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and 7 carbon atoms
-18 aralkyl group, C2-C18 acyl group, C1-C18 alkyl or arylsulfonyl group, C1-C18 alkylsulfinyl group, C6-C1
8 alkoxycarbonyl group, 7 to 18 carbon atom aryloxycarbonyl group, 1 to 18 carbon atom alkoxy group, 6 to 18 carbon atom aryloxy group, 1 to 1 carbon atom
8, an alkylthio group having 8 to 18 carbon atoms, an arylthio group having 6 to 18 carbon atoms, an acyloxy group having 2 to 18 carbon atoms,
An amide group, a ureido group having 1 to 18 carbon atoms, a sulfonyloxy group, a carbamoyloxy group, an amino group, a carbamoyl group, a sulfamoyl group, a halogen atom, a hydroxyl group, a nitro group, a cyano group, a carboxyl group, and 4 to
Represents one substituent selected from the group consisting of a 7-membered heterocyclic group (these substituents are further selected from the group consisting of the substituents represented by A ³ , A ⁴ , B ³ and B ⁴ above) Optionally substituted with at least one group), Y ² and Z ²
Each independently represents an atomic group necessary for forming a 4- to 7-membered carbocyclic ring or a 4- to 7-membered heterocyclic ring (these rings further include A ³ , A ⁴ , B ³ and B ^And may be substituted with at least one group selected from the group consisting of the substituents represented by 4;
Or a 6-membered heterocyclic ring), L ⁶ , L ⁷ ,
L ⁸ , L ⁹ and L ¹⁰ are each independently A ³ , A
⁴ , a methine group which may be substituted with one or two groups selected from the group consisting of substituents represented by B ³ and B ⁴ , m1 and n1 each independently represent 0, 1 or 2 And k1 represents an integer necessary to neutralize the counter cation; R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ are each independently a hydrogen atom Or A ³ and A
⁴ represents one group selected from the group consisting of substituents represented by B ³ and B ⁴ (provided that R ²¹ and R ²² , R ²³ and R ²⁴ ,
R ²⁵ and R ²⁶ and R ²⁷ and R ²⁸ may be linked to each other to form a heterocyclic ring with a nitrogen atom), R ²⁹ , R ³⁰ , R ³¹ , R
³² and R ³³ each independently represent one group selected from the group consisting of the substituents represented by A ³ , A ⁴ , B ³ and B ⁴ , p 1 represents 1 or 2, and q 1 And r1
Each independently represents an integer of 0 to 4] Wherein ^{R 21, R 22, R 23} , R 24, R 25, R 26,
R ²⁷ and R ²⁸ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, and 6 to 10 carbon atoms.
The information recording medium according to claim 4, which represents an aryl group of 7 to 10 carbon atoms, an aralkyl group of 7 to 10 carbon atoms, or an alkoxy group of 1 to 8 carbon atoms. 6. R ²¹ and R ²² , R ²³ and R ²⁴ , R ²⁵ and R ²⁶ ,
5. The information recording medium according to claim 4, wherein the heterocyclic ring formed by R ²⁷ and R ²⁸ each being linked together with a nitrogen atom is a 4- to 7-membered unsubstituted heterocyclic ring. 7. The information recording medium according to claim 1, wherein X ¹ is ＯO, and X ² is −0. 8. m and n are both 1 or m
The information recording medium according to claim 1, wherein is 0 and n is 2, or m is 2 and n is 0. 9. The information recording medium according to claim 1, further comprising a reflective layer provided on the recording layer. 10. The compound represented by the general formula (II-1) or (II-
2) An oxonol compound represented by the general formula (II-3) or (II-4). Embedded image Embedded image [Wherein A ³ , A ⁴ , B ³ and B ⁴ are each independently a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, An alkynyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and 7 carbon atoms
-18 aralkyl group, C2-C18 acyl group, C1-C18 alkyl or arylsulfonyl group, C1-C18 alkylsulfinyl group, C6-C1
8 alkoxycarbonyl group, 7 to 18 carbon atom aryloxycarbonyl group, 1 to 18 carbon atom alkoxy group, 6 to 18 carbon atom aryloxy group, 1 to 1 carbon atom
8, an alkylthio group having 8 to 18 carbon atoms, an arylthio group having 6 to 18 carbon atoms, an acyloxy group having 2 to 18 carbon atoms,
An amide group, a ureido group having 1 to 18 carbon atoms, a sulfonyloxy group, a carbamoyloxy group, an amino group, a carbamoyl group, a sulfamoyl group, a halogen atom, a hydroxyl group, a nitro group, a cyano group, a carboxyl group, and 4 to
Represents one substituent selected from the group consisting of a 7-membered heterocyclic group (these substituents are further selected from the group consisting of the substituents represented by A ³ , A ⁴ , B ³ and B ⁴ above) Optionally substituted with at least one group), Y ² and Z ²
Each independently represents an atomic group necessary for forming a 4- to 7-membered carbocyclic ring or a 4- to 7-membered heterocyclic ring (these rings further include A ³ , A ⁴ , B ³ and B ^And may be substituted with at least one group selected from the group consisting of the substituents represented by 4;
Or a 6-membered heterocyclic ring), L ⁶ , L ⁷ ,
L ⁸ , L ⁹ and L ¹⁰ are each independently A ³ , A ⁴ ,
B represents ³ and one or two methine group optionally substituted with a group chosen from the group consisting of substituents represented by B ^4, m1 and n1 each independently represent 0, 1 or 2,
And k1 represents an integer necessary to neutralize the counter cation; R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ and R
²⁸ independently represent a hydrogen atom or the above-mentioned A ³ , A ⁴ , B
Represents one group selected from the group consisting of substituents represented by ³ and B ⁴ (provided that R ²¹ and R ²² , R ²³ and R ²⁴ , R ²⁵ and R ^26, and R ²⁷ and R ²⁸ each represent R ²⁹ , R ³⁰ , R ³¹ , R ³² and R ³³ may be independently represented by A ³ , A ⁴ , B ³ and B ⁴ described above. Represents one group selected from the group consisting of substituted substituents, p1 represents 1 or 2, and q1 and r1 each independently represent an integer of 0 to 4.] 11. m1 and n1 are both 1 or m1
11. The oxonol compound according to claim 10, wherein n is 0 and n1 is 2, or m1 is 2 and n1 is 0.