JP2001138633A - Optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a write-once optical information recording medium capable of high-sensitivity optical recording in a blue light region and capable of supporting a recording / reproducing wavelength of 400 to 450 nm. SOLUTION: It is represented by the following general formula (I), and X _{1 to} X ₈ are each a hydrogen atom or a fluorine atom, which may be the same or different, and R _{1 to} R ₄ are represented by a specific chemical formula. And an optical information recording medium characterized by using a porphyrin derivative, which may be the same or different, as a recording layer. Embedded image (In the above formula, M represents two hydrogen atoms, or a divalent, trivalent, or tetravalent metal atom which may have oxygen or halogen, or (OR ₅ ) p, (OSiR ₆ R ₇ R ₈ ) Q, (OP
OR ₉ R ₁₀ ) represents a metal atom which may have r or (OCOR ₁₁ ) s, and R _{5 to} R ₁₁ independently represent a hydrogen atom, a substituted or unsubstituted aliphatic or aromatic hydrocarbon group. , P,
q, r, and s represent an integer of 0 to 2. )

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recordable optical information recording medium on which information is recorded and reproduced optically, and more particularly to a recordable optical information recording medium using an organic dye as a recording material. is there.

[0002]

2. Description of the Related Art As a laser beam for recording and reproducing information on and from an optical information recording medium, a laser beam in the red to infrared region is used.
Recording media corresponding to this have become widespread. For example,
A disc-shaped optical information recording medium (CD-R,
DVD-R) is one such example. The write-once optical information recording medium has a configuration in which a recording layer made of, for example, an organic dye is formed on a substrate, and recording is usually performed in a heat mode. That is, when the recording layer is irradiated with laser light, light energy is converted to heat by light absorption of the organic dye,
Pits are formed by the generated heat. And
The pit is detected by a difference in reflectance based on a phase change between a portion where the pit is formed and a portion where the pit is not formed when the laser beam is irradiated.

In order to increase the recording density by recording / reproducing at the conventional laser wavelength, a device such as so-called super-resolution is required. However, in recent years, the practical use of semiconductor lasers in the blue light region has been becoming feasible, and it has become possible to increase the amount of recorded information without contriving such super-resolution. The oscillation wavelength of the semiconductor laser corresponding to the blue light region is 40
The wavelength is expected to be 0 to 450 nm, and it is necessary to shorten the wavelength of the recording material accordingly. In general, organic materials having a maximum absorption wavelength of about 350 to 450 nm generally have a small molecular skeleton, and therefore have a low molecular extinction coefficient, and almost no material exceeds 100,000. In general, there are few compounds having sufficient solubility.

[0004] As one of the materials that can solve this problem,
There are porphyrin derivatives. A porphyrin derivative is a metal complex having a structure in which an atomic group is coordinated to a central metal, and contains at least 38 π electrons (the number of π electrons increases with a substituent). This porphyrin derivative has a 16-membered ring (18 π-electron system) in the molecular absorption spectrum.
Has an absorption band called a Soret band (S band) on the short wavelength side. This Soret band has a very large molecular extinction coefficient of 100,000 or more, and high sensitivity optical recording in the blue light region is possible by using this large absorption band. A porphyrin derivative is promising as a material recordable / reproducible at 400 to 450 nm, but many porphyrin derivatives cannot cope with a short wavelength of 400 to 450 nm.

As a short-wavelength recording medium using a porphyrin derivative, Japanese Patent Application Laid-Open No. 7-304256 discloses "an optical information recording medium comprising a porphyrin derivative and a polymer having a molecular structure having a coordinating ability in a side chain". Japanese Patent Application Laid-Open No. Hei 7-304257 discloses "an optical information recording medium comprising a porphyrin derivative and a molecular compound having a coordinating ability and a polymer", all of which have a wavelength matching property in a short wavelength region. It was intended, but its recording wavelength was 480
490 nm, which is expected to be put to practical use in the future.
It cannot be adapted to a recording / reproducing wavelength of 00 to 450 nm at all.

In the inventions disclosed in these publications, a molecular compound having a coordinating ability or a polymer having a molecular structure having a coordinating ability in a side chain is coordinated with a central metal of a porphyrin derivative. The main focus is on increasing the extinction coefficient and shifting the absorption wavelength of the Soret band to longer wavelengths. In the inventions disclosed in these publications, tetraphenyltetrabenzporphyrin is basically used as a porphyrin derivative. Since tetraphenyltetrabenzporphyrin has an absorption wavelength near 470 nm,
Recording and reproduction cannot be performed with a semiconductor laser having an oscillation wavelength of 0 nm. Therefore, the recording described in the examples of these publications is performed by an Ar laser (wavelength is 488 nm).

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of such conventional circumstances, and enables high-sensitivity optical recording in the blue light region, and has a recording / reproducing wavelength of 400 to 450 nm. An object of the present invention is to provide a write-once optical information recording medium that can be used.

[0008]

According to the present invention, in order to solve the problems] In order to solve the above problems, it is represented by the following general formula (I), X ₁ ~
X ₈ is a hydrogen atom or a fluorine atom, which may be the same or different, and R _{1 to} R ₄ are represented by the following general formula (II), and these are porphyrin derivatives which may be the same or different. An optical information recording medium characterized by being used as a recording layer is provided.

Embedded image

Embedded image(In the above formula, Y₁~ Y_FiveAre each independently a hydrogen atom, halo
Gen atom, nitro group, cyano group, hydroxyl group, carboxyl
Group, substituted or unsubstituted alkyl group, substituted or unsubstituted
Substituted alkoxy group, substituted or unsubstituted aryl
Group, substituted or unsubstituted amino group, or substituted or
Represents an unsubstituted acyl group, M represents two hydrogen atoms,
Is divalent, trivalent, which may have oxygen or halogen, or
A tetravalent metal atom, or (OR_Five) P, (OSiR₆R₇R
₈) Q, (OPOR₉R_Ten) R, (OCOR)₁₁Have s
Represents a good metal atom;_Five~ R₁₁Is independently a hydrogen atom,
Substituted or unsubstituted aliphatic or aromatic hydrocarbon group
And p, q, r, and s represent an integer of 0 to 2. )
According to the present invention, X is represented by the following general formula (I):₁
~ X₈Consists of a hydrogen atom or a fluorine atom,
May be the same or different, and R ₁~ R_FourBut
It is represented by the following general formula (II), and one or more of these are
Are hydrogen atoms and the rest are the same or different
Porphyrin derivative that may be used as the recording layer
An optical information recording medium is provided.

Embedded image

Embedded image (In the above formula, Y _{1 to} Y ₅ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted Represents a substituted aryl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted acyl group, and M represents two hydrogen atoms, or divalent, trivalent, or Valent metal atom, or (OR ₅ ) p, (OSiR ₆ R ₇ R
₈ ) represents a metal atom which may have q, (OPOR ₉ R ₁₀ ) r, and (OCOR ₁₁ ) s, wherein R _{5 to} R ₁₁ are each independently a hydrogen atom,
It represents a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, and p, q, r, and s represent an integer of 0 to 2. According to the present invention, there is provided an optical information recording medium characterized in that a porphyrin derivative in which, except for Y ₃ , a hydrogen atom or a fluorine atom is used as a recording layer. Further, according to the present invention, there is provided an optical information recording medium having the above-mentioned configuration, wherein a porphyrin derivative in which a plurality of Y _{1 to} Y ₅ are fluorine atoms is used as a recording layer. Further, according to the present invention, in the above configuration, at least a recording layer and a reflective layer are sequentially laminated on at least the substrate, and the recording layer has a recording / reproducing wavelength of 400 to 450 n.
An optical information recording medium is provided that conforms to the formula:

An optical information recording medium to which the present invention is applied has, for example, a structure as shown in FIG. That is, the recording layer 2 and the reflective layer 3 are sequentially formed on the substrate 1, and the protective layer 4 is further formed thereon. In this optical information recording medium, recording is performed by a heat mode method in which pits are formed by heat generated by irradiating the recording layer 2 with the laser light 5.

As a result of intensive studies, the present inventor has found that a specific substitution position at a specific substitution position in the porphyrin derivative represented by the above general formula (I) can be used as a recording layer material for an optical information recording medium having the above structure. Those having a substituent are 400 to
It has been found that recording and reproduction can be performed in a short wavelength region of 450 nm.

The porphyrin derivative has a smaller molecular skeleton than naphthalocyanine and phthalocyanine, and has a carbon at the meso position.
It has the property of being easily distorted. for that reason,
For example, even when an electron-withdrawing substituent is introduced, the HOMO is stabilized by the substituent effect, and if the steric hindrance by the adjacent substituent is increased, the HOMO is more destabilized due to distortion. It will become. For example, tetraphenylporphyrin is (X ₁ -X ₈ = H, R ₁ -R ₄
= C ₆ H ₅ ), and has a maximum absorption wavelength around 415 to 420 nm, so that a recording / reproducing wavelength of about 450 nm is the optimum wavelength. This is because the optimum recording / reproducing wavelength is in the vicinity of the wavelength at which the refractive index of the recording material is maximized, and has a suitable k (absorption coefficient).
This is because it is necessary to set the maximum absorption wavelength and the optimum recording / reproducing wavelength when one absorption spectrum exists alone. It shifts from the maximum absorption wavelength to the longer wavelength side.

The reason for adapting the recording / reproducing wavelength to the vicinity of the maximum wavelength of the refractive index is that the recording is basically performed by the change of the refractive index before and after the recording of the recording material. It is preferable to use the highest wavelength region, and the vicinity of the maximum refractive index wavelength is located at the base of the absorption spectrum. In the case of a write-once optical information recording medium, high reflectivity, that is, ROM and (The high modulation degree and the high reflectance are compatible.) The amount of deviation between the maximum absorption wavelength and the maximum refractive index wavelength varies depending on the width of the absorption band and the magnitude of the absorption coefficient, but is generally 10 to 40 nm. Therefore, 400-45
In order to adapt to the laser wavelength of 0 nm, the maximum wavelength of the absorption spectrum in the solution or film of the recording material is 37.
It is preferably in the range of about 0 to 420 nm. However, since it is important that the complex refractive index is optimized at the recording / reproducing wavelength, a material in which the maximum wavelength of the absorption spectrum of a solution or a film deviates from 370 to 420 nm is not excluded.

The porphyrin derivative is 400 to 450 n
With respect to the recording / reproducing wavelength of m, many have an absorption peak at a long wavelength, and as described above, distortion due to the introduction of a substituent is apt to occur, so that it has been extremely difficult to achieve wavelength matching.

The present invention is intended to provide a saddle-shaped modification even if a relatively large phenyl group is introduced into R _{1 to} R ₄ , if a substituent having no great steric hindrance to the phenyl group is selected in X _{1 to} X _8. It is noted that such a large porphyrin skeleton deformation does not occur. In an optical information recording medium using a conventional organic material, wavelength matching is mainly performed by a HOM due to a substituent effect.
Although this is performed by changing the O and LUMO, when this saddle type deformation occurs, the substituent effect is not effective, the wavelength becomes longer due to structural distortion, and this wavelength fluctuation is extremely large. Because of the wavelength change based on the above, it is impossible to achieve the delicate wavelength matching required for the optical information recording medium using an organic material, because the molecular design is not easy. Further, when a large structural change is caused, the molecular extinction coefficient is greatly reduced, and the characteristics of high reflectance and high sensitivity are lost.

For tetraphenylporphyrin, about 4
Although it is suitable for a laser wavelength of about 50 nm, if it is necessary to achieve minute wavelength matching, or to improve solubility and crystallinity according to the oscillation wavelength of a practically used semiconductor laser, a porphyrin skeleton is required. It is necessary to cause a minute change in wavelength due to the substituent effect without causing large distortion. Therefore, as X _{1 to} X ₈ , a substituent having a macrocyclic structure such as a phenyl group, a substituent having a branched structure at a position close to a pyrrole ring carbon (for example, an alkyl group having a branched portion), or R ₁ to R 3 as exacerbate sterically hindered substituted or unsubstituted phenyl group of ₄
A substituent having a dimensional spread is not preferred, and a hydrogen atom or a fluorine atom is preferred. These atoms having a small three-dimensional spread can suppress porphyrin ring distortion due to steric hindrance with R _{1 to} R _4, and X _{1 to} X ₈ and R _{1 to} R ₄
Can effectively exert the effect of the substituent introduced into the compound, and it is possible to achieve delicate wavelength matching.
Therefore, by using the porphyrin derivative of the present invention, it is possible to effectively prevent the substituent effect due to introduction of an electron-withdrawing or electron-donating substituent in order to prevent the substituent effect from being invalidated due to molecular skeleton distortion. In addition, molecular design for wavelength matching becomes easy.

The invention of each claim will be described below. In the invention of claim 1, X _{1 to} X ₈ in the general formula (I) are used.
And a combination of substituents for preventing unnecessarily increasing the steric hindrance between R _{1 and} R ₄ , and it has been found that the combination can support a recording / reproducing wavelength of 400 to 450 nm. . That is, when X _{1 to} X ₈ are hydrogen atoms, steric hindrance with R _{1 to} R ₄ can be minimized, and there is an effect of preventing an increase in wavelength due to porphyrin ring distortion. , And when it is a fluorine atom, H
It is possible to shorten the wavelength based on OMO stabilization.
Further, when X _{1 to} X ₈ are hydrogen atoms or fluorine atoms, even if an electron-withdrawing or electron-donating substituent is introduced into Y _{1 to} Y ₅ , a large distortion of the porphyrin skeleton is not caused. It has been found that the electronic substituent effect of _{1 to} Y ₅ can be sufficiently exerted. Claim 2
According to the invention of the first aspect, X _{1 to} X ₈ and R ₁ to R are the same as in the _{first aspect.
4} to provide a combination of substituents so as not to unnecessarily increase the steric hindrance between the 4
It has been found that it is possible to cope with a recording / reproducing wavelength of up to 450 nm. That is, when X _{1 to} X ₈ are hydrogen atoms, steric hindrance with R _{1 to} R ₄ can be minimized, and there is an effect of preventing an increase in wavelength due to porphyrin ring distortion. , that is when the fluorine atom is possible to reduce the wavelength based on the stabilization of the HOMO, also X ₁
To X ₈ and by a hydrogen atom or fluorine atom, Y ₁
Be introduced electron withdrawing or electron donating substituents to Y _5, because not to cause significant distortion of the porphyrin skeleton, it electronic substituent effect of Y ₁ to Y ₅ is capable of exerting sufficient Is found. The invention of claim 3 further restricts the invention of claims 1 and 2, and R ₁
If substituents Y ₁ to Y ₅ is introduced as to R _4, other than Y ₃ is that a hydrogen atom or a fluorine atom,, X ₁
Between to X ₈ and R ₁ to R _4, without increasing more than necessary steric hindrance between R ₁ to R ₄ and porphyrin skeleton, it has been found to be very effective in shorter wavelength. That is, X ₁
When X ₈ is a hydrogen atom, steric hindrance with R _{1 to} R ₄ can be minimized, and there is an effect of preventing a long wavelength or the like due to porphyrin ring distortion. In that case, it is possible to shorten the wavelength based on the stabilization of HOMO, and X _{1 to} X ₈ are hydrogen atoms or fluorine atoms, and R _{1 to} R ₄ are hydrogen atoms other than Y ₃ , Alternatively, since the steric hindrance with the porphyrin skeleton or X _{1 to} X ₈ can be reduced by using a fluorine atom, even if an electron-withdrawing or electron-donating substituent is introduced into Y ₃ , the porphyrin It has been found that it is possible to exert the effect of the electronic substituent by Y _{1 to} Y ₅ sufficiently without causing a large distortion in the skeleton. The invention of claim 4 further restricts the invention of claims 1 and 2, and
_{When a} substituent is introduced into Y ₁ to Y ₅ as _{1 to} R ₄ , Y ₁
X _{1 to} X ₈ by making a plurality of Y to Y ₅ fluorine atoms.
It has been found that the steric hindrance between R ₁ and R _{1 to} R ₄ is not unnecessarily increased, and is very effective in shortening the wavelength.
That is, when X _{1 to} X ₈ are hydrogen atoms, R _{1 to} R ₄
Steric hindrance to the minimum, there is an effect of preventing a longer wavelength due to porphyrin ring distortion,
When a fluorine atom is used, it is possible to shorten the wavelength based on the stabilization of HOMO, and when X _{1 to} X ₈ are a hydrogen atom or a fluorine atom, and R _{1 to} R ₄ are Y ₁
A plurality of locations to be able to reduce the steric hindrance of the porphyrin skeleton and X ₁ to X ₈ by a fluorine atom deli to Y _5, fluorine atoms introduced at a plurality of Y ₁ to Y ₅ It has been found that the effect and the effect of the electron-withdrawing and electron-donating substituents introduced in addition to the fluorine atoms of Y _{1 to} Y ₅ do not cause large distortion in the porphyrin skeleton, and thus can be sufficiently worked. It is a thing. The substituents introduced into Y ₁ to Y _{5 according} to claims 1 to 4 include:
Specifically, each independently represents a hydrogen atom, a halogen atom,
Nitro group, cyano group, hydroxyl group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted amino group, substituted or unsubstituted Although it represents an acyl group, it is important that the porphyrin skeleton is not significantly distorted in any case of the substituent. For this purpose, a branched alkyl, particularly a porphyrin skeleton, or a branch portion in the space close to X _{1 to} X _8. Such as an alkyl moiety,
Substituents having a bulky alkyl moiety such as an alkyl moiety having a very long straight chain or a cycloalkyl moiety are not preferred.

In the present invention, when an electron-withdrawing group is introduced into Y ₁ to Y ₅ , the effect of lowering the thermal decomposition starting temperature can be expected, and it is very preferable. Further, in the present invention, the wavelength can be shortened by not distorting the porphyrin skeleton, as well as the wavelength can be shortened by the effect of the electronic substituent, so that a high absorption coefficient of the polymer can be achieved and excellent optical characteristics can be secured. There is. Further, the porphyrin derivative used in the present invention has a phenyl group introduced into R _{1 to} R ₄ , which can prevent association between molecules, has high solubility, and has an effect of preventing crystallization. Preferred.

In the formula (II), Y _{1 to} Y ₅ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group. Represents a group, a substituted or unsubstituted aryl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted acyl group.

Examples of the alkyl group in the unsubstituted alkyl group and the unsubstituted alkoxy group include a linear or branched alkyl group, and include the substituted alkyl group and the substituted alkyl group in the substituted alkoxy group. As 2
-Hydroxyethyl group, 3-hydroxypropyl group, 4
A hydroxy-substituted alkyl group such as -hydroxybutyl group or 2-hydroxypropyl group; a carboxymethyl group,
Carboxy-substituted alkyl groups such as carboxyethyl group and 3-carboxypropyl group; cyano-substituted alkyl groups such as 2-cyanoethyl group and cyanomethyl group; amino-substituted alkyl groups such as 2-aminoethyl group; 2-chloroethyl group and 3-chloro Propyl group, 2-chloropropyl group,
A halogen atom-substituted alkyl group such as a 2,2,2-trifluoroethyl group; a benzyl group, a p-chlorobenzyl group,
A phenyl-substituted alkyl group such as a 2-phenylethyl group;
2-methoxyethyl group, 2-ethoxyethyl group, 2-
(N) propoxyethyl group, 2- (iso) propoxyethyl group, 2- (n) butoxyethyl group, 2- (is
o) Alkoxy-substituted alkyl groups such as butoxyethyl group, 2- (2-ethylhexyloxy) ethyl group, 3-methoxypropyl group, 4-methoxybutyl group and 2-methoxypropyl group; 2- (2-methoxyethoxy) ethyl Group,
2- (2-ethoxyethoxy) ethyl group, 2- (2-
(N) propoxyethoxy) ethyl group, 2- (2- (i
so) propoxyethoxy) ethyl group, 2- (2-
(N) butoxyethoxy) ethyl group, 2- (2- (is
o) an alkoxyalkoxy-substituted alkyl group such as a butoxyethoxy) ethyl group and a 2- {2- (2-ethylhexyloxy) ethoxy} ethyl group; an allyloxyethyl group;
A substituted alkyl group such as a 2-phenoxyethyl group and a 2-benzyloxyethyl group; a 2-acetyloxyethyl group;
Acyloxy-substituted alkyl groups such as -propionyloxyethyl group, 2- (n) butyryloxyethyl group, 2- (iso) butyryloxyethyl group and 2-trifluoroacetyloxyethyl group; methoxycarbonylmethyl group, ethoxycarbonyl Methyl group, (n) propoxycarbonylmethyl group, (iso) propoxycarbonylmethyl group, (n) butoxycarbonylmethyl group, (is
o) butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, benzyloxycarbonylmethyl group, furfuryloxycarbonylmethyl group, tetrahydrofurfuryloxycarbonylmethyl group, 2-methoxycarbonylethyl group, 2-ethoxycarbonylethyl group, 2- (n) propoxycarbonylethyl group, 2
-(Iso) propoxycarbonylethyl group, 2-
(N) substitution with butoxycarbonylethyl group, 2- (iso) butoxycarbonylethyl group, 2- (2-ethylhexyloxycarbonyl) ethyl group, 2-benzyloxycarbonylethyl group, 2-furfuryloxycarbonylethyl group, or Unsubstituted alkoxycarbonyl-substituted alkyl group; 2-methoxycarbonyloxyethyl group, 2-ethoxycarbonyloxyethyl group, 2-
(N) propoxycarbonyloxyethyl group, 2- (i
so) a propoxycarbonyloxyethyl group, 2-
(N) butoxycarbonyloxyethyl group, 2- (is
o) butoxycarbonyloxyethyl group, 2- (2-ethylhexyloxycarbonyloxy) ethyl group, 2-
A substituted or unsubstituted alkoxycarbonyloxy-substituted alkyl group such as a benzyloxycarbonyloxyethyl group or a 2-furfuryloxycarbonyloxyethyl group;
Examples include a heterocyclic-substituted alkyl group such as a furfuryl group and a tetrahydrofurfuryl group.

Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group.

Specific examples of the alkyl group in the alkyl group and the alkoxy group include the following. Note that these alkyl groups may be substituted with a substituent such as a halogen atom. Methyl group, ethyl group, n
-Propyl, n-butyl, isobutyl, n-pentyl, neopentyl, isoamyl, 2-methylbutyl, n-hexyl, 2-methylpentyl, 3-
Methylpentyl group, 4-methylpentyl group, 2-ethylbutyl group, n-heptyl group, 2-methylhexyl group, 3
-Methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 2-ethylpentyl group, 3-ethylpentyl group, n-octyl group, 2-methylheptyl group, 3-
Primary alkyl groups such as methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 2-ethylhexyl group, 3-ethylhexyl group, n-nonyl group, n-decyl group and n-dodecyl group; isopropyl group, sec -Butyl group, 1-ethylpropyl group, 1-methylbutyl group, 1,
2-dimethylpropyl group, 1-methylheptyl group, 1-
Ethylbutyl group, 1,3-dimethylbutyl group, 1,2-
Dimethylbutyl group, 1-ethyl-2-methylpropyl group, 1-methylhexyl group, 1-ethylheptyl group, 1
-Propylbutyl group, 1-isopropyl-2-methylpropyl group, 1-ethyl-2-methylbutyl group, 1-propyl-2-methylpropyl group, 1-methylheptyl group,
1-ethylhexyl group, 1-propylpentyl group, 1-
Isopropylpentyl group, 1-isopropyl-2-methylbutyl group, 1-isopropyl-3-methylbutyl group,
Secondary alkyl groups such as 1-methyloctyl group, 1-ethylheptyl group, 1-propylhexyl group, 1-isobutyl-3-methylbutyl group; tert-butyl group, tert
Tertiary alkyl groups such as -hexyl group, tert-amyl group and tert-octyl group; cyclohexyl group, 4-methylcyclohexyl group, 4-ethylcyclohexyl group, 4
And cycloalkyl groups such as -tert-butylcyclohexyl group, 4- (2-ethylhexyl) cyclohexyl group, bornyl group, isobornyl group and adamantane group.

Examples of the aryl group include phenyl, methylphenyl, dimethylphenyl, trimethylphenyl, ethylphenyl, tert-butylphenyl, di (tert-butyl) phenyl, butylphenyl, methoxyphenyl, Examples thereof include a dimethoxyphenyl group, a trimethoxyphenyl group, and a butoxyphenyl group. These aryl groups may be substituted with a substituent such as halogen.

In the above general formula (I), M represents two hydrogen atoms, or divalent, trivalent, which may have oxygen or halogen.
Or a tetravalent metal atom, or (OR ₅ ) p, (OSi
_{R 6 R 7 R 8) q} , (OPOR 9 R 10) r, (OCOR 11) s
R _{5 to} R _{11 each} independently represent a hydrogen atom, a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, and p, q, r, and s represent 0 to 2 Represents an integer. Specifically, M includes Ib, IIa, IIb, IIIa, I
Group Va, Group IVb, Group Vb, Group VIb, Group VIIb, Group VIII metals, oxides of these metals, halides of these metals or hydroxides of these metals, and the like.
Some of the above metals have a substituent. The above metals include Cu, Zn, Mg, Al, Ge, Ti, Sn, P
b, Cr, Mo, Mn, Fe, Co, Ni, In, P
t, Pd and the like; oxides such as TiO and VO; and halides such as AlCl, GeCl ₂ , S
There are iCl ₂ , FeCl, SnCl ₂ , InCl and the like, and hydroxides of Al (OH), Si (OH) ₂ , Ge (OH) ₂ , Sn
(OH) _{2 and the} like. Further, when the metal has a substituent, examples of the metal include Al, Ti, Si, Ge, and Sn, and examples of the substituent include an aryloxyl group, an alkoxyl group, a trialkylsiloxyl group, and a triarylsiloxyl group. Group, trialkoxysiloxyl group, triaryloxysiloxyl group, trityloxyl group or acyloxyl group.

Hereinafter, layer constituting materials that can be used in the present invention will be described. << Recording Layer >> The recording layer is basically composed of a porphyrin derivative. If necessary, for example, a polymethine dye, a squarylium-based, a coronium-based, a pyrylium-based, a naphthoquinone-based, an anthraquinone (indanthrene) -based, a xanthene-based, or triphenyl-based Methane-based, azulene-based, tetrahydrocholine-based, phenanthrene-based, triphenothiazine-based dyes, metal complex compounds, and the like may be appropriately mixed and used. Metals and metal compounds such as I
n, Te, Bi, Al, Be, TeO ₂ , SnO, A
s, Cd, etc. can be used in the form of dispersion mixing or lamination. Further, various materials such as a polymer material, for example, an ionomer resin, a polyamide resin, a vinyl resin, a natural polymer, silicone, and a liquid rubber, or a silane coupling agent may be dispersed and used in the dye. It can be used together with a stabilizer (for example, a transition metal complex), a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, and the like for the purpose of improving the properties. When using a coating method, the above dye or the like is dissolved in an organic solvent, and spraying, roller coating,
The coating is performed by a conventional coating method such as dipping and spin coating, but spin coating is most preferable due to the nature of the present invention. As an organic solvent,
In general, alcohols such as methanol, ethanol and isopropanol, ketones such as acetone, methyl ethyl ketone and cyclohexanone, amides such as N, N-dimethylacetamide and N, N-dimethylformamide, sulfoxides such as dimethyl sulfoxide, tetrahydrofuran, dioxane, Ethers such as diethyl ether and ethylene glycol monomethyl ether,
Esters such as methyl acetate and ethyl acetate, aliphatic halogenated carbons such as chloroform, methylene chloride, dichloroethane, carbon tetrachloride, and trichloroethane; or aromatics such as benzene, xylene, monochlorobenzene, and dichlorobenzene, and methoxyethanol And sorbanols such as ethoxyethanol, and hydrocarbons such as hexane, pentane, cyclohexane, and methylcyclohexane. The thickness of the recording layer is 1
A suitable range is from 00 to 10 μm, preferably from 200 to 2000 μm.

<< Substrate >> The required characteristic of the substrate is that it must be transparent to the laser beam used only when recording / reproducing from the substrate side, and transparent when recording / reproducing from the recording layer side. No need. As the substrate material, for example,
Plastic such as polyester, acrylic resin, polyamide, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, and polyimide, glass, ceramic, and metal can be used.
When only one substrate is used, or when two substrates are used in a sandwich shape, it is necessary that guide grooves and guide pits for tracking and preformats such as address signals are formed on the surface of the substrate.

<< Intermediate Layer >> Layers provided other than the substrate, the recording layer, the reflective layer, and the protective layer, including the undercoat layer and the like, are referred to as intermediate layers. This intermediate layer comprises (a) improved adhesion, (b) a barrier against water or gas, (c) improved storage stability of the recording layer, (d) improved reflectance, and (e) substrate from solvent. And (f) formation of guide grooves, guide pits, preformats, and the like. For the purpose of (a), a polymer material, for example, various polymer materials such as an ionomer resin, a polyamide resin, a vinyl resin, a natural resin, a natural polymer, a silicone, a liquid rubber, and a silane coupling agent are used. For the purposes of (b) and (c), other than the above-mentioned polymer materials, inorganic compounds such as SiO ₂ , Mg
Metals such as F ₂ , SiO, TiO ₂ , ZnO, TiN, SiN, or metalloids such as Zn, Cu, Ni, Cr, G
e, Se, Au, Ag, Al and the like can be used. For the purpose of (d), a metal such as Al, A
g or an organic thin film having a metallic luster such as a methine dye or a xanthene dye. For the purposes of (e) and (f), an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin, or the like can be used. Can be used. The thickness of the undercoat layer is 0.01 to 30 μm, preferably 0.05 to 10 μm.
μm is appropriate.

<< Protective Layer / Hard Coat Layer on Substrate Surface >> The protective layer or hard coat layer on the substrate surface (a) protects the recording layer (reflection / absorption layer) from scratches, dust, dirt, etc., (b)
It is used for the purpose of improving the storage stability of the recording layer (reflection / absorption layer) and (c) improving the reflectance. For these purposes, the materials shown in the undercoat layer can be used. As the inorganic material, SiO, SiO ₂ or the like can be used. As the organic material, polymethyl acrylate, polycarbonate, epoxy resin, polystyrene,
Heat softening and heat melting resins such as polyester resin, vinyl resin, cellulose, aliphatic hydrocarbon resin, aromatic hydrocarbon resin, natural rubber, styrene-butadiene resin, chloroprene rubber, wax, alkyd resin, drying oil and rosin Can also be used. Among the above materials, the most preferable substance for the protective layer or the hard coat layer on the substrate surface is an ultraviolet curable resin having excellent productivity. The thickness of the protective layer or the hard coat layer on the substrate surface is suitably 0.01 to 30 μm, preferably 0.05 to 10 μm. In the present invention, the undercoat layer, the protective layer, and the substrate hard coat layer, as in the case of the recording layer, a stabilizer, a dispersant,
Flame retardants, lubricants, antistatic agents, surfactants, plasticizers and the like can be contained.

<< Metal Reflective Layer >> The reflective layer is made of a metal, a semi-metal, or the like, which can provide a high reflectance by itself and is hardly corroded.
Examples of the material include Au, Ag, Cu, Cr, Ni, and Al, and preferably Ag and Al, which can achieve high reflectance even at a short wavelength. These metals and metalloids may be used alone or as two or more alloys. Further, a dielectric multilayer film may be used. Examples of the film forming method include vapor deposition and sputtering, and the film thickness is 50 to 3000 °, preferably 100 to 100 °.
00 °.

<< Adhesive Layer >> An adhesive layer is required when two thin substrates are bonded to each other as seen in DVD media. Particularly preferred in the present invention is a hot-melt type (hot-melt type) adhesive or an ultraviolet curable type adhesive.
The ultraviolet curable adhesive is an adhesive which is cured by the initiation of radical polymerization by irradiation with ultraviolet light. The composition is generally composed of (1) an acrylic oligomer, (2) an acrylic monomer, (3) a photopolymerization initiator, and (4) a polymerization inhibitor. The oligomer is a polyester-based, polyurethane-based, or epoxy-based. Benzophenone, benzoin ether and the like can be used as a photopolymerization initiator such as an acrylate ester. The hot melt adhesive is one in which a liquid adhesive is hardened by solvent volatilization or reaction and develops an adhesive force, whereas an ordinary-temperature solid thermoplastic resin develops an adhesive force by a physical change of heat melting and cooling and solidification. Hot melt adhesive is EVA,
Polyester, polyamide, polyurethane and the like can be used.

[0030]

The present invention will be described in more detail with reference to the following examples. In the porphyrin derivative represented by the general formula (I) specified in the present invention, X in Tables 1 and 2
_{1 ~X 8, R 1 ~R 4} , and were measured a maximum absorption wavelength and molecular extinction coefficient in the spectrum of the solution having a M. However, due to the yield of the synthesized porphyrin derivative, the molecular extinction coefficient could not be measured in all samples.

[0031]

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

From these measurement results, the porphyrin derivative specified in the present invention has a sufficient solubility,
It was found that recording and reproduction were possible with a laser wavelength of 450 nm, and that the material had a molecular absorption coefficient almost equivalent to that of conventional CD-R and DVD-R materials. Further, the films formed on the respective glass substrates did not show deterioration such as crystallization over time. X ₁ described in Tables 3 to 5 as a comparative example
The maximum absorption wavelength and the molecular extinction coefficient in the spectrum of the solution of the porphyrin derivative having ＸX ₈ , R _{1 to} R ₄ and M were measured. Since none of these porphyrin derivatives satisfy the combination of X _{1 to} X ₈ and R _{1 to} R ₄ specified in the present invention, the recording / reproducing wavelength is 400 to 4
It was confirmed that it was unsuitable as a 50 nm optical information recording medium.

[0033]

The specific porphyrin derivative used for the recording layer in the optical information recording medium of the present invention has a high solubility and the film is not crystallized, and the recording layer formed by using this has a wavelength of 400 to 450 nm. High contrast and high contrast can be achieved in the range. In addition, the optical information recording medium using the specific porphyrin derivative of the present invention as a recording layer allows the R to be reduced even in a short wavelength region of 400 to 450 nm.
An optical information recording medium compatible with OM can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a layer configuration example of an optical information recording medium according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Recording layer 3 Reflection layer

Claims (5)

[Claims] 1. A compound represented by the following general formula (I), wherein X _{1 to} X ₈ are each a hydrogen atom or a fluorine atom, which may be the same or different, and R _{1 to} R ₄ are each represented by the following general formula (I) An optical information recording medium represented by II), wherein porphyrin derivatives which may be the same or different from each other are used as a recording layer. Embedded image Embedded image (In the above formula, Y _{1 to} Y ₅ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted Represents a substituted aryl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted acyl group, and M represents two hydrogen atoms, or divalent, trivalent, or Valent metal atom, or (OR ₅ ) p, (OSiR ₆ R ₇ R
₈ ) represents a metal atom which may have q, (OPOR ₉ R ₁₀ ) r, and (OCOR ₁₁ ) s, wherein R _{5 to} R ₁₁ are each independently a hydrogen atom,
It represents a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, and p, q, r, and s represent an integer of 0 to 2. ) 2. A compound represented by the following general formula (I), wherein X _{1 to} X ₈ are each a hydrogen atom or a fluorine atom, which may be the same or different, and R _{1 to} R _{4 are represented by the following} general formula (II) Wherein at least one of these is a hydrogen atom, and the other is a porphyrin derivative, which may be the same or different, used as a recording layer. Embedded image Embedded image (In the above formula, Y _{1 to} Y ₅ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a carboxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted Represents a substituted aryl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted acyl group, and M represents two hydrogen atoms, or divalent, trivalent, or Valent metal atom, or (OR ₅ ) p, (OSiR ₆ R ₇ R
₈ ) represents a metal atom which may have q, (OPOR ₉ R ₁₀ ) r, and (OCOR ₁₁ ) s, wherein R _{5 to} R ₁₁ are each independently a hydrogen atom,
It represents a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, and p, q, r, and s represent an integer of 0 to 2. ) 3. The optical information recording medium according to claim 1, wherein a porphyrin derivative other than Y ₃ is a hydrogen atom or a fluorine atom as a recording layer. 4. The optical information recording medium according to claim 1, wherein a porphyrin derivative in which a plurality of Y _{1 to} Y ₅ are fluorine atoms is used as a recording layer. 5. A recording layer and a reflection layer are sequentially laminated on at least a substrate, and the recording layer has a recording / reproducing wavelength of 400 to 45.
2. The method according to claim 1, wherein the thickness is adapted to 0 nm.
5. The optical information recording medium according to any one of items 4 to 4.