JP2003094814A - Optical information recording medium and information recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical information recording medium, to and from which recording and regeneration can be possible with semiconductor laser beams, the wavelength of which is shorter than that used in CD-R and DVD-R, especially shorter than 450 nm and is near 405 nm having a high versatility, and, at the same time, which has excellent recording characteristics. SOLUTION: In the optical information recording medium having a recording layer, on which information can be recorded through the irradiation of laser beams having the wavelength of 450 nm or less, on a substrate, the recording layer includes a tetraazaporphyrin compound or a triazaporphyrin compound.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an optical information recording medium and an information recording method capable of recording and reproducing information by using a laser beam. Particularly, the present invention has a wavelength of 4
The present invention relates to a heat mode type optical information recording medium suitable for recording information using a short wavelength laser beam of 50 nm or less.

[0002]

2. Description of the Related Art Conventionally, an optical information recording medium (optical disk) capable of recording information only once with a laser beam has been known. This optical disc is a write-once CD (so-called CD
-R), and its typical structure is such that a recording layer made of an organic dye, a light reflection layer made of metal such as gold, and a resin protective layer are laminated in this order on a transparent disc-shaped substrate. It is provided. The recording of information on the CD-R is performed by irradiating the CD-R with laser light in the near infrared region (usually, laser light having a wavelength near 780 nm), and the irradiated portion of the recording layer emits the light. Information is recorded by absorbing and locally raising the temperature, causing a physical or chemical change (eg, pit formation) that alters its optical properties. On the other hand, reading (reproduction) of information is also performed by irradiating a laser beam having the same wavelength as the recording laser beam, and the part where the optical characteristics of the recording layer have changed (recorded part) and the part that has not changed (unrecorded part) The information is reproduced by detecting the difference in reflectance with the (part).

In recent years, there has been a demand for an optical information recording medium having a higher recording density. In response to such a demand, an optical disc called a write-once type digital versatile disc (so-called DVD-R) has been proposed (for example, "Nikkei New Media" separate volume "DVD", published in 1995).
This DVD-R is a transparent disc-shaped substrate in which the guide groove (pre-groove) for tracking the emitted laser light is formed to be narrower than half (0.74 to 0.8 μm) as compared with the CD-R. Two recording discs each having a recording layer made of a dye, and usually a light reflection layer on the recording layer, and a protective layer if necessary, or a disc-shaped protective substrate having the same shape as the discs. It has a structure in which the recording layer is placed inside and is bonded with an adhesive. Recording / reproduction of information to / from a DVD-R is performed by a visible laser light (usually 630n
It is performed by irradiating a laser beam having a wavelength in the range of m to 680 nm), and it is said that recording at a higher density than CD-R is possible.

Recently, networks such as the Internet and high-definition TV have been rapidly spread. Also, HDT
V (High Definition Televisions)
Ion) is coming soon, and there is an increasing demand for a large-capacity recording medium for easily and inexpensively recording image information. Although the DVD-R secures its position as a large-capacity recording medium to some extent, it cannot be said that the DVD-R has a sufficiently large recording capacity to meet future requirements.
Therefore, the development of an optical disc having a larger recording capacity by improving the recording density by using a laser beam having a shorter wavelength than that of the DVD-R is under way. For example, JP-A-4-74690 and JP-A-7-30425.
6, JP-A-7-304257, JP-A-8-
No. 127174, No. 11-221964, No. 11-53758, No. 11-334204, No. 11-334205, No. 11-33420.
No. 6, JP-A No. 11-334207, JP-A-2000
-43423, 2000-108513, 2000-113504, 2000-1.
49320, 2000-158818,
2000-228028 and 2001-80.
No. 217, in an optical information recording medium having a recording layer containing an organic dye, recording and reproduction of information is performed by irradiating a laser beam having a wavelength of 530 nm or less from the recording layer side to the light reflecting layer side. A reproduction method is disclosed. Specifically, as an optical disk using a porphyrin compound, an azo dye, a metal azo dye, a quinophthalone dye, a trimethine cyanine dye, a dicyanovinylphenyl skeleton dye, a coumarin compound, a naphthalocyanine compound, etc. as a dye of the recording layer. , Blue (wavelength 430nm, 488
(nm) or blue-green (wavelength 515 nm) laser light has been proposed to record and reproduce information. Also, from the viewpoint of compatibility with the current DVD-R system, an optical recording medium capable of recording / reproducing with laser light of two different wavelength regions has been proposed. For example, Japanese Patent Laid-Open No. 11-78239 and 1
Japanese Patent Application Laid-Open No. 1-105423 proposes a recording medium capable of recording by any laser light by using a mixture of a dye used for blue laser light recording and a dye used in DVD-R. There is.

[0005]

DISCLOSURE OF THE INVENTION According to the study by the present inventor,
It was found that the optical disk described in the above publication needs further improvement in practical use because it is still insufficient in sensitivity and recording characteristics such as reflectance and modulation. An object of the present invention is that recording / reproducing is possible and excellent with laser light having a shorter wavelength than that of CD-R and DVD-R, particularly with a wavelength of 450 nm or less, and particularly with semiconductor laser light having a wavelength of 405 nm which is highly versatile. An object of the present invention is to provide an optical information recording medium having recording characteristics. Further, the object of the present invention is to use an optical information recording medium provided with a recording layer containing a dye compound exhibiting high sensitivity to short-wavelength laser light,
An object of the present invention is to provide an information recording method capable of high density recording of information. Furthermore, another object of the present invention is to simply form a recording layer using substantially one compound (azaporphyrin compound), and to use the above-mentioned short wavelength laser light and conventional D
It is to enable recording or reproduction by both of the long-wavelength laser light used in VD-R, and as a result to expand the versatility of the recording medium.

[0006]

[Means for Solving the Problems] According to the research by the present inventor,
When a tetraazaporphyrin compound or triazaporphyrin is used as the recording material for the recording layer, the wavelength of 45
It has been found that it is possible to manufacture an optical information recording medium having high sensitivity to a laser beam having a short wavelength of 0 nm or less and having a high reflectance and a good recording / reproducing characteristic which gives a high degree of modulation. At the same time, wavelengths of 630 to 680 nm
It has been found that it is possible to manufacture an optical information recording medium exhibiting high sensitivity to long-wavelength laser light, and having high reflectance and high recording and reproducing characteristics.

The optical information recording medium of the present invention is an optical information recording medium having a recording layer on a substrate capable of recording information by irradiation with a laser beam having a wavelength of 450 nm or less, wherein the recording layer is a tetraazaporphyrin compound or It is characterized by containing a triazaporphyrin compound.

The present invention also provides an information recording method for recording information by irradiating the optical information recording medium with laser light having a wavelength of 450 nm or less, and a wavelength 630 for the same recording medium.
There is also an information recording method of recording information by irradiating a laser beam of ˜680 nm.

The optical information recording medium of the present invention preferably has the following modes. (1) The tetraazaporphyrin compound or the triazaporphyrin compound is represented by the following general formula (I).

[0010]

[Chemical 1]

In the general formula (I), X represents methine carbon or azamethine nitrogen, M represents two hydrogen atoms, a metal atom, a metal oxide or a metal atom having a ligand, and any carbon in the formula. You may have a substituent on the atom.

(2) In the general formula (I), M is copper, nickel, iron, cobalt, palladium, magnesium, aluminum, zinc or silicon.

(3) In the general formula (I), the substituent on the carbon atom is a halogen atom, a cyano group, a nitro group, a formyl group, a carboxyl group, a sulfo group, or a carbon number of 1 to 2.
0 alkyl group, C6-14 aryl group, C7-15 aralkyl group, C1-10
Heterocyclic group, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, and 2 to 2 carbon atoms
21 acyl group, C1-20 alkylsulfonyl group, C6-14 arylsulfonyl group, C7-15 aralkylsulfonyl group, C1-10 heterylsulfonyl group, carbon atom Number 1-20
An alkoxysulfonyl group, a carbamoyl group having 1 to 25 carbon atoms, a sulfamoyl group having 0 to 32 carbon atoms,
Alkoxycarbonyl group having 1 to 20 carbon atoms, aryloxycarbonyl group having 7 to 15 carbon atoms, acylamino group having 2 to 21 carbon atoms, sulfonylamino group having 1 to 20 carbon atoms, and 0 to 36 carbon atoms. When there are plural substituents, the respective substituents may be the same or different from each other.

(4) A light reflecting layer made of metal is provided in addition to the recording layer. (5) A protective layer is provided separately from the recording layer. (6) The substrate has a track pitch of 0.2 to 0.
It is a transparent disk-shaped substrate having a pregroove of 8 μm formed, and a recording layer is provided on the surface on the side where the pregroove is formed.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The optical information recording medium of the present invention is characterized in that the recording layer contains a tetraazaporphyrin compound or a triazaporphyrin compound.

The tetraazaporphyrin compound or triazaporphyrin compound used in the optical information recording medium of the present invention is preferably a compound represented by the following general formula (I).

[0017]

[Chemical 2]

In the formula, X represents a methine carbon or an azamethine nitrogen, M represents two hydrogen atoms, a metal atom, a metal oxide or a metal atom having a ligand, which is substituted on any carbon atom in the formula. It may have a group.

In the general formula (I), X is preferably azamethine nitrogen.

In the general formula (I), the substituent on the carbon atom includes a halogen atom, a cyano group, a nitro group, a formyl group, a carboxyl group, a sulfo group, and a carbon number of 1 to 2.
0 alkyl group, C6-14 aryl group, C7-15 aralkyl group, C1-10
Heterocyclic group, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, and 2 to 2 carbon atoms
21 acyl group, alkylsulfonyl group having 1 to 20 carbon atoms, arylsulfonyl group having 6 to 14 carbon atoms,
Aralkylsulfonyl group having 7 to 15 carbon atoms, Heterylsulfonyl group having 1 to 10 carbon atoms, 1 to 1 carbon atoms
20 alkoxysulfonyl group, carbamoyl group having 1 to 25 carbon atoms, sulfamoyl group having 0 to 32 carbon atoms, alkoxycarbonyl group having 1 to 20 carbon atoms, aryloxycarbonyl group having 7 to 15 carbon atoms, carbon Acylamino group having 2 to 21 atoms, 1 to 20 carbon atoms
And the amino group having 0 to 36 carbon atoms. When there are a plurality of substituents, the respective substituents may be the same as or different from each other. Among the above substituents, a halogen atom, an alkyl group having 1 to 16 carbon atoms, an aryl group having 6 to 10 carbon atoms, and 7 to 7 carbon atoms.
An aralkyl group of 11, a heterocyclic group having 1 to 7 carbon atoms,
Alkoxy group having 1 to 16 carbon atoms, 6 to 1 carbon atoms
0 aryloxy group, C 2-17 acyl group, C 1-16 alkylsulfonyl group, C 6-10 arylsulfonyl group, C 1
To 16 carbamoyl group, 0 to 16 carbon atom sulfamoyl group, 2 to 17 carbon atom alkoxycarbonyl group, 7 to 11 carbon atom aryloxycarbonyl group, 2 to 18 carbon atom acylamino group, carbon A sulfonylamino group having 1 to 18 atoms is preferable.

In the general formula (I), the above-mentioned substituent may further have a substituent, and examples of the substituent include those described below. 1 to 1 carbon atoms
20 chain or cyclic alkyl groups (eg methyl,
Ethyl, isopropyl, cyclohexyl), an aryl group having 6 to 18 carbon atoms (eg, phenyl, chlorophenyl, 2,4-di-t-amylphenyl, 1-naphthyl), an aralkyl group having 7 to 18 carbon atoms (eg, , Benzyl, anisyl), an alkenyl group having 2 to 20 carbon atoms (for example, vinyl, 2-methylvinyl), an alkynyl group having 2 to 20 carbon atoms (for example, ethynyl, 2-methylethynyl, 2-phenylethynyl). , A halogen atom (eg, F, Cl, Br, I), a cyano group, a hydroxyl group, a carboxyl group, an acyl group having 2 to 20 carbon atoms (eg, acetyl, benzoyl, salicyloyl, pivaloyl), 1 to 1 carbon atoms 20 alkoxy groups (eg methoxy, butoxy, cyclohexyloxy), C6-20 alkenyl groups. Aryloxy group (e.g., phenoxy, 1-naphthoxy, toluoyl), 1 carbon atoms
20 alkylthio group (eg, methylthio, butylthio, benzylthio, 3-methoxypropylthio), arylthio group having 6 to 20 carbon atoms (eg, phenylthio, 4-chlorophenylthio), alkylsulfonyl group having 1 to 20 carbon atoms (Eg, methanesulfonyl, butanesulfonyl), arylsulfonyl group having 6 to 20 carbon atoms (eg, benzenesulfonyl, paratoluenesulfonyl), carbamoyl group having 1 to 17 carbon atoms (eg, unsubstituted carbamoyl, methylcarbamoyl). , Ethylcarbamoyl, n-butylcarbamoyl, dimethylcarbamoyl), an amide group having 1 to 16 carbon atoms (eg, acetamide, benzamide), an acyloxy group having 2 to 10 carbon atoms (eg, acetoxy, benzoyloxy), carbon Alkoxycarbonyl groups having 2 to 10 children (eg, methoxycarbonyl, ethoxycarbonyl), 5-membered or 6-membered heterocyclic groups (eg, pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, and other aromatic heterocycles, pyrrolidine ring,
Heterocycles such as piperidine ring, morpholine ring, pyran ring, thiopyran ring, dioxane ring, dithiolane ring).

In the general formula (I), preferred substituents for the above substituents are linear or cyclic alkyl groups having 1 to 16 carbon atoms, aryl groups having 6 to 14 carbon atoms, and 7 carbon atoms. ~ 15 aralkyl groups, 1 carbon atom
To an alkoxy group having 16 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, a halogen atom, an alkoxycarbonyl group having 2 to 17 carbon atoms, a carbamoyl group having 1 to 10 carbon atoms, and an amide group having 1 to 10 carbon atoms. Among them, preferred are linear or cyclic alkyl groups having 1 to 10 carbon atoms, aralkyl groups having 7 to 13 carbon atoms, and 6 carbon atoms.
-10 aryl group, C1-10 alkoxy group, C6-10 aryloxy group, chlorine atom, C2-11 alkoxycarbonyl group, C1-7 carbamoyl group , An amide group having 1 to 8 carbon atoms, particularly preferably an amide group having 3 to 10 carbon atoms.
A branched chain or cyclic alkyl group having 7 to 11 carbon atoms
Is an aralkyl group, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 3 to 9 carbon atoms, phenyl and a chlorine atom.

In the general formula (I), when there are a plurality of substituents on a carbon atom, the plurality of substituents may be the same or different, but the same is preferable. In the general formula (I), M is preferably a metal, of which copper, nickel or palladium is preferable, copper or nickel is more preferable, and copper is particularly preferable.

The tetraazaporphyrin compound or the triazaporphyrin compound represented by the general formula (I) may be combined at any position to form a multimer, and the respective units in this case are the same or different from each other. Or may be bonded to a polymer chain such as polystyrene, polymethacrylate, polyvinyl alcohol, or cellulose.

The tetraazaporphyrin compound or triazaporphyrin compound represented by the general formula (I) used in the optical information recording medium of the present invention may be used as a specific derivative alone, or may have different structures. A plurality of kinds of materials may be mixed and used, but it is preferable to use them alone.
In addition, the tetraazaporphyrin compound or the triazaporphyrin compound represented by the general formula (I) may inevitably contain substitution position isomers in which the substitution positions of the substituents are different during the synthesis. Regioisomers are regarded as the same derivative without distinguishing from each other. Also, when the substituents include isomers, they are regarded as the same compound without distinction. Therefore, the case where the structures are different is either the case where the constituent atom species or number of the substituents are different or the case where the number of the substituents is different.

Preferred specific examples of the tetraazaporphyrin compound and the triazaporphyrin compound used in the present invention are shown below, but the present invention is not limited thereto.

[0027]

[Chemical 3]

[0028]

[Chemical 4]

[0029]

[Chemical 5]

[0030]

[Chemical 6]

[0031]

[Chemical 7]

[0032]

[Chemical 8]

[0033]

[Chemical 9]

[0034]

[Chemical 10]

The tetraazaporphyrin compound and the triazaporphyrin compound used in the present invention are described, for example, by Shirai-Kobayashi, "Phthalocyanine-Chemical and Function-" (P. 1-62), published by IPC Co., Ltd., C.I. C. Lez
noff-A. B. P. Lever co-authored, VCH published'Phthalocyanines-Properti
es and Applications' (P. 1-
54) and the like, or can be synthesized by a method similar to these.

The optical information recording medium of the present invention has a recording layer containing the tetraazaporphyrin compound or the triazaazaporphyrin compound on the substrate. The optical information recording medium of the present invention includes those having various configurations. The optical information recording medium of the present invention has a structure in which a recording layer, a light reflection layer and a protective layer are provided in this order on a disk-shaped substrate on which pregrooves having a constant track pitch are formed, or a light reflection layer and a recording layer are formed on the substrate. A structure having a layer and a protective layer in this order is preferable. In addition, two laminated bodies each having a recording layer and a light reflecting layer provided on a transparent disc-shaped substrate having a pregroove with a constant track pitch are joined so that each recording layer is on the inside. The configuration is also preferable.

The optical information recording medium of the present invention has a higher recording density than that of the CD-R or DVD-R.
It is possible to use a substrate having pregrooves with a narrower track pitch. In the case of the optical information recording medium of the present invention, the track pitch is preferably in the range of 0.2 to 0.8 μm, further preferably in the range of 0.2 to 0.5 μm, and particularly 0.27 to It is preferably in the range of 0.40 μm. The depth of the pregroove is
It is preferably in the range of 0.03 to 0.18 μm,
Further, it is preferably in the range of 0.05 to 0.15 μm, and particularly preferably in the range of 0.06 to 0.1 μm.

A method of manufacturing the optical information recording medium of the present invention will be described below by taking as an example an optical information recording medium having a recording layer, a light reflecting layer, and a protective layer in this order on a disk-shaped substrate. The substrate of the optical information recording medium of the present invention can be arbitrarily selected from various materials used as the substrate of the conventional optical information recording medium. Examples of the substrate material include glass, polycarbonate, acrylic resin such as polymethylmethacrylate, polyvinyl chloride, vinyl chloride resin such as vinyl chloride copolymer, epoxy resin, amorphous polyolefin and polyester. You may use them together. Note that these materials can be used as a film or as a rigid substrate. Among the above materials, polycarbonate is preferable from the viewpoint of moisture resistance, dimensional stability, price, and the like.

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 and preventing alteration of the recording layer. Examples of the material for the undercoat layer include polymethylmethacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylolacrylamide, styrene / vinyltoluene copolymer, and chlorosulfonate. Polymer substances such as polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene and polycarbonate; and silane coupling agents. Surface modifiers such as The undercoat layer is formed by dissolving or dispersing the above substances in a suitable solvent to prepare a coating solution, and then coating the coating solution on the substrate surface by a coating method such as spin coating, dip coating, or extrusion coating. can do.
The layer thickness of the undercoat layer is generally in the range of 0.005 to 20 μm, preferably 0.01 to 10 μm.

The recording layer is formed by vapor deposition, sputtering,
Although it can be performed by a method such as CVD or solvent coating, solvent coating is preferable. In this case, the dye compound,
Further, if desired, a quencher, a binder and the like are dissolved in a solvent to prepare a coating solution, and then the coating solution is applied to the surface of the substrate to form a coating film, followed by drying. Solvents for the coating liquid include esters such as butyl acetate, methyl lactate, and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform; dimethylformamide and the like. Amides; hydrocarbons such as methylcyclohexane; ethers such as dibutyl ether, diethyl ether, tetrahydrofuran, dioxane; alcohols such as ethanol, n-propanol, isopropanol, n-butanol, diacetone alcohol;
Fluorine-based solvents such as 2,3,3-tetrafluoropropanol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and the like. The above solvents may be used alone or in combination of two or more in consideration of the solubility of the dye used. Various additives such as an antioxidant, a UV absorber, a plasticizer and a lubricant may be further added to the coating liquid depending on the purpose.

When a binder is used, examples of the binder include natural organic polymer substances such as gelatin, cellulose derivatives, dextran, rosin and rubber; and hydrocarbon-based substances such as polyethylene, polypropylene, polystyrene and polyisobutylene. Resins, vinyl-based resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride / polyvinyl acetate copolymers, acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resins, Examples thereof include synthetic organic polymers such as butyral resins, rubber derivatives, and initial condensation products of thermosetting resins such as phenol / formaldehyde resins. When a binder is used in combination as a material for the recording layer, the amount of the binder used is generally in the range of 0.01 to 50 times the mass (mass ratio), preferably 0.
It is in the range of 1-fold amount to 5-fold amount (mass ratio). The concentration of the dye in the coating solution thus prepared is generally 0.01.
It is in the range of 10 to 10% by mass, and preferably in the range of 0.1 to 5% by mass.

Examples of the coating method include spraying method, spin coating method, dipping method, roll coating method, blade coating method, doctor roll method and screen printing method. The recording layer may be a single layer or multiple layers. The thickness of the recording layer is generally in the range of 20 to 500 nm, preferably 30 to 300 nm, and more preferably 5.
It is in the range of 0 to 100 nm.

The recording layer may contain various anti-fading agents in order to improve the light resistance of the recording layer.
A singlet oxygen quencher is generally used as the anti-fading agent. As the singlet oxygen quencher, those described in publications such as already known patent specifications can be used. A specific example thereof is Japanese Patent Laid-Open No. 58-175.
No. 693, No. 59-81194, No. 60-18387.
No. 60, No. 60-19586, No. 60-19587, No. 60-35054, No. 60-36190, No. 60-
No. 36191, No. 60-45454, No. 60-445.
55, 60-44389, 60-44390.
No. 60-54892, No. 60-47069, No. 63-209995, JP-A No. 4-25492, Japanese Examined Patent Publication No. 1-38680, and No. 6-26028, and German Patent 350399. And those described in October 1992, page 1141 of the Chemical Society of Japan. Examples of preferable singlet oxygen quencher include compounds represented by the following general formula (II).

[0044]

[Chemical 11]

However, R ²¹ represents an alkyl group which may have a substituent, and Q ⁻ represents an anion.

In the general formula (II), R ²¹ is generally an optionally substituted alkyl group having 1 to 8 carbon atoms, and an unsubstituted alkyl group having 1 to 6 carbon atoms is preferable. As the substituent of the alkyl group, a halogen atom (eg, F, Cl),
Alkoxy group (eg, methoxy, ethoxy), alkylthio group (eg, methylthio, ethylthio), acyl group (eg,
Acetyl, propionyl), acyloxy group (eg, acetoxy, propionyloxy), hydroxy group, alkoxycarbonyl group (eg, methoxycarbonyl, ethoxycarbonyl), alkenyl group (eg, vinyl), aryl group (eg, phenyl, naphthyl) Can be mentioned.
Of these, a halogen atom, an alkoxy group, an alkylthio group and an alkoxycarbonyl group are preferable. Preferred examples of the anion of Q ⁻ include ClO ₄ ⁻ , AsF ₆ ⁻ , B
F ₄ ⁻ and SbF ₆ ⁻ may be mentioned. General formula (II)
Examples of compounds represented by are shown in Table 1.

[0047]

[Table 1]

The amount of the anti-fading agent such as the singlet oxygen quencher used is usually 0.1 to 50 relative to the amount of the dye.
It is in the range of mass%, preferably 0.5 to 45 mass%.
Is more preferable, the range of 3 to 40% by mass is more preferable, and the range of 5 to 25% by mass is particularly preferable.

It is preferable to provide a light reflecting layer adjacent to the recording layer for the purpose of improving the reflectance when reproducing information. The light-reflecting substance, which is the material of the light-reflecting layer, is a substance having a high reflectance to the laser light.
g, Se, Y, Ti, Zr, Hf, V, Nb, Ta, C
r, Mo, W, Mn, Re, Fe, Co, Ni, Ru,
Rh, Pd, Ir, Pt, Cu, Ag, Au, Zn, C
d, Al, Ga, In, Si, Ge, Te, Pb, P
Examples thereof include metals such as o, Sn, and Bi, and semimetals, or stainless steel. These substances may be used alone, in a combination of two or more, or as an alloy. Of these, the preferred one is
Cr, Ni, Pt, Cu, Ag, Au, Al and stainless steel. Particularly preferably, Au metal, Ag metal,
Al metal or an alloy thereof, most preferably Ag metal, Al metal or an alloy thereof.
The light reflecting layer can be formed on the substrate or the recording layer by vapor deposition, sputtering or ion plating of the above light reflecting substance. The layer thickness of the light reflection layer is generally in the range of 10 to 300 nm, preferably 50 to 200 nm.

A protective layer is preferably provided on the light reflection layer or the recording layer for the purpose of physically and chemically protecting the recording layer and the like. It should be noted that the protective layer is not necessarily required in the case of the same form as in the case of manufacturing the DVD-R type optical information recording medium, that is, in the case where two substrates are laminated with the recording layer inside. Examples of materials used for the protective layer include SiO, SiO ₂ , MgF ₂ , Sn.
Examples thereof include inorganic substances such as O ₂ and Si ₃ N ₄ , and organic substances such as thermoplastic resins, thermosetting resins, and UV curable resins. The protective layer can be formed, for example, by laminating a film obtained by extrusion processing of plastic on the reflective layer via an adhesive. Or vacuum deposition,
It may be provided by a method such as sputtering or coating. Further, in the case of a thermoplastic resin or a thermosetting resin, it can also be formed by dissolving these in an appropriate solvent to prepare a coating solution, applying the coating solution, and then 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 this coating solution, and irradiating it with UV light to cure it. Various additives such as an antistatic agent, an antioxidant and a UV absorber may be added to these coating solutions depending on the purpose. The layer thickness of the protective layer is generally in the range of 0.1 μm to 1 mm. Through the above steps, it is possible to manufacture a laminated body in which the recording layer, the light reflecting layer and the protective layer are provided on the substrate, or the light reflecting layer, the recording layer and the protective layer are provided on the substrate.

The optical information recording method of the present invention is performed using the above recording medium, for example, as follows. First, set the optical information recording medium at a constant linear velocity (1.2-
1.4 m / sec) or while rotating at a constant angular velocity, light for recording such as semiconductor laser light is irradiated from the substrate side or the protective layer side. This light irradiation causes the recording layer to absorb the light and locally raise the temperature, causing a physical or chemical change (for example, formation of pits) and changing its optical characteristics to record information. It is thought to be done. In the present invention, the recording light is 450 nm or less,
Alternatively, semiconductor laser light having an oscillation wavelength of 630 to 680 nm is used. 390 as a preferred light source
A blue-violet semiconductor laser light having an oscillation wavelength in the range of up to 415 nm, and an infrared semiconductor laser light having a central oscillation wavelength of 850 nm half the wavelength using an optical waveguide element. You can In particular, it is preferable to use blue-violet semiconductor laser light in terms of recording density. To reproduce the information recorded as described above, the semiconductor laser light is irradiated from the substrate side or the protective layer side while rotating the optical information recording medium at the same constant linear velocity as above, and the reflected light is detected. Can be done by.

[0052]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[Example 1] Compounds (I-1)
It was dissolved in 3,3-tetrafluoropropanol to obtain a recording layer forming coating liquid (concentration: 1% by mass). Spiral pre-groove (track pitch:
Polycarbonate substrate (diameter: 120 mm, thickness: 0.6 m) in which 0.4 μm, groove width: 0.2 μm, groove depth: 0.08 μm) were formed by injection molding.
m) was applied to the surface on the pregroove side by a spin coating method, and the recording layer (thickness (in the pregroove): about 80 n)
m) was formed. Next, silver was sputtered on the recording layer to form a light reflection layer having a thickness of about 100 nm. Further, a UV curable resin (SD318, manufactured by Dainippon Ink and Chemicals, Inc.) was applied on the light reflection layer and irradiated with ultraviolet rays to be cured to form a protective layer having a layer thickness of 7 μm. The optical disk (optical information recording medium) of Example 1 was obtained through the above steps.

[Example 2] to [Example 10] In the same manner as in Example 1, except that the compound shown in Table 2 was used instead of the compound (I-1) (the amount used was not changed). Two to ten optical disks were manufactured.

[Comparative Example 1] to [Comparative Example 6] The same as Example 1 except that the compound (I-1) was changed to the following comparative dye compounds AF (the amount used was not changed). Then, the optical disks of Comparative Examples 1 to 6 were manufactured.

[0056]

[Chemical 12]

[0057]

[Chemical 13]

[Evaluation 1 as optical disc] A 14T-EFM signal was recorded on the produced optical disc at a linear velocity of 3.5 m / sec using a blue-violet semiconductor laser beam having an oscillation wavelength of 405 nm, and then the recorded signal was reproduced. Degree of modulation at optimum power, groove reflectance, and sensitivity were measured. Recording and evaluation of recording characteristics are made by Pulstec DDU1000
Was performed using. The evaluation results are shown in Table 2.

[0059]

[Table 2]

From the results shown in Table 2, an optical disk having a recording layer containing a tetraazaporphyrin compound or a triazaporphyrin compound, which is a feature of the present invention (Examples 1 to 1)
8) shows a higher reflectance to the blue-violet semiconductor laser light and gives a higher degree of modulation than the optical discs having the recording layer containing the comparative compounds A to E (Comparative Examples 1 to 5), and It can be seen that the sensitivity is high. Therefore, it can be seen that by using the tetraazaporphyrin compound or the triazaporphyrin compound according to the present invention, an optical disk having high recording characteristics for short wavelength laser light can be obtained.

Example 11 The compound (I-3) was dissolved in dibutyl ether to obtain a coating liquid for forming a recording layer (concentration: 1% by mass). A spiral pre-groove (track pitch: 1.0 μm, groove width:
Polycarbonate substrate (diameter: 12) with 0.4 μm and groove depth: 0.15 μm formed by injection molding
A recording layer (thickness (in the pre-groove): about 170 nm) was formed on the surface of the pre-groove side having a thickness of 0 mm and a thickness of 0.6 mm by spin coating. Next, silver was sputtered on the recording layer to form a light reflection layer having a thickness of about 100 nm. Furthermore, a UV curable resin (SD3
No. 18, Dainippon Ink and Chemicals, Inc. was applied and cured by irradiation with ultraviolet rays to form a protective layer having a layer thickness of 7 μm. An optical disk of Example 11 was obtained through the above steps.

[Evaluation 2 as Optical Disc] After recording a 14T-EFM signal on an optical disc at a linear velocity of 1.4 m / sec using a semiconductor laser beam having an oscillation wavelength of 650 nm,
The signal recorded with the same laser beam and the blue-violet semiconductor laser beam having an oscillation wavelength of 405 nm was reproduced, and the reproduced signal waveform of each was observed. As a result, the same clear reproduced signal waveform could be observed with any semiconductor laser beam having a different wavelength.

[0063]

The use of the tetraazaporphyrin compound or the triazaporphyrin compound, which is a feature of the present invention, shows a high reflectance for a laser beam having a short wavelength of 450 nm or less, and a high sensitivity that gives a high degree of modulation. An optical information recording medium and an information recording method can be obtained.
Therefore, it is possible to provide high density recording of information as compared with the case of CD-R and DVD-R, and it is possible to provide an optical information recording medium capable of recording a large amount of information. Further, by using the dye compound which is a feature of the present invention, the laser light used in DVD-R and the laser light having a short wavelength of 450 nm or less can be obtained without using a recording layer in which two kinds of dyes are mixed. It is possible to obtain an optical information recording medium capable of recording and reproducing by both of the above. Therefore, a versatile recording medium can be easily provided.

Claims (3)

[Claims] 1. An optical information recording medium having a recording layer capable of recording information by irradiating a laser beam having a wavelength of 450 nm or less on a substrate, the recording layer containing a tetraazaporphyrin compound or a triazaporphyrin compound. An optical information recording medium characterized by the above. 2. An information recording method comprising irradiating the optical information recording medium according to claim 1 with laser light having a wavelength of 450 nm or less to record information. 3. An information recording method comprising irradiating the optical information recording medium according to claim 1 with laser light having a wavelength of 630 to 680 nm to record information.