JP2007276438A - Optical information recording medium and method for recording information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical information recording medium capable of well performing high density recording and reproducing of information performed by laser light irradiation with a wave length of ≤440 nm, and having good optical storing properties, and to provide a method for recording the information on the optical information recording medium. <P>SOLUTION: The optical information recording medium has a recording layer capable of recording the information by the laser light irradiation with a wave length of ≤440 nm on a substrate. The optical recording information medium is characterized in that the recording layer comprises a coloring matter having at least two coloring matter residues independently in the molecule and these coloring matter residues bind together without placing a conjugated bond between them. In addition, the method for recording the information is characterized in that the information is recorded by irradiating the optical information recording medium with the laser light with the wave length of ≤440 nm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical information recording medium and an information recording method capable of recording and reproducing information using a laser beam. In particular, the present invention relates to a heat mode type optical information recording medium and information recording method suitable for recording information using a short wavelength laser beam having a wavelength of 440 nm or less.

  Conventionally, an optical information recording medium (optical disc) capable of recording information only once by laser light is known. This optical disk is also called a recordable CD (so-called CD-R), and its typical structure is a recording layer made of an organic dye on a transparent disk-shaped substrate, a light reflecting layer made of a metal such as gold, and a resin. A protective layer made of a metal is provided in this order in a laminated state. Information recording on this CD-R is performed by irradiating the CD-R with a near-infrared laser beam (usually a laser beam 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 generation) and changing its optical properties. On the other hand, reading (reproduction) of information is also performed by irradiating laser light having the same wavelength as the recording laser light, and the part where the optical characteristics of the recording layer have changed (recorded part) and the part not changed (unrecorded) Information is reproduced by detecting the difference in reflectance from (part).

  Recently, networks such as the Internet and high-definition TV are rapidly spreading. Also, due to the broadcast of HDTV (High Definition Television), there is an increasing demand for a large-capacity recording medium for easily and inexpensively recording image information. The above-mentioned CD-R and a write-once digital vasatile disc (so-called DVD-R) capable of high-density recording using a visible laser beam (630 nm to 680 nm) as a recording laser are positioned as large-capacity recording media. However, it cannot be said that the recording capacity is sufficiently large to meet future demands. Therefore, development of an optical disc having a higher recording capacity by using a laser beam having a shorter wavelength than that of a DVD-R has been developed. For example, a Blu-ray method using a blue laser of 405 nm An optical recording disk called “Launch” was launched.

  In an optical information recording medium having a recording layer containing an organic dye, a recording / reproducing method for recording / reproducing information by irradiating a laser beam having a wavelength of 530 nm or less from the recording layer side toward the light reflecting layer side is disclosed. Yes. Specifically, porphyrin compounds, azo dyes, metal azo dyes, quinophthalone dyes, trimethine cyanine dyes, dicyanovinylphenyl skeleton dyes, coumarin compounds, phthalocyanine compounds, naphthalocyanine compounds are used as recording layer dyes. There has been proposed an information recording / reproducing method for recording / reproducing information by irradiating a conventional optical disk with blue (wavelength 430 nm, 488 nm) or blue-green (wavelength 515 nm) laser light. In addition, an information recording / reproducing method has been proposed in which information is recorded / reproduced by irradiating an optical disk using an oxonol dye as a dye of a recording layer with a laser beam of 550 nm or less (for example, see Patent Documents 1 to 21).

However, according to the study of the present inventor, the recording characteristics of the optical disk using the known dye described in the above publication are not satisfactory. In addition, the optical disk using the oxonol dyes disclosed in Patent Document 21 is unsatisfactory in practical use because the oxonol dyes used in the patent have low optical storage stability. Further, although the oxonol dye described in Patent Document 22 has sufficient light preservability, no dye that can record information with a laser having a wavelength of 440 nm or less is described.
JP 2001-287460 A JP 2001-287465 A JP 2001-253171 A JP 2001-39034 A JP 2000-318313 A JP 2000-318312 A JP 2000-280621 A JP 2000-280620 A JP 2000-263939 A JP 2000-222772 A JP 2000-222771 A JP 2000-218940 A JP 2000-158818 A JP 2000-149320 A JP 2000-108513 A JP 2000-113504 A JP 2002-301870 A JP 2001-287465 A US Patent 2002 / 76648A1 JP 2003-94828 A JP 2001-71638 A JP 2004-188968 A

  In view of the above, an object of the present invention is to solve the above conventional problems. That is, it is an object of the present invention to satisfactorily perform high-density recording and reproduction of information performed by laser light irradiation of 440 nm or less, and to provide an optical information recording medium having good optical storage stability and the optical information recording medium. It is to provide an information recording method.

  The present inventors have found that the above problem can be solved by using a dye having a specific structure, and have completed the present invention. That is, the present invention is an optical information recording medium having a recording layer capable of recording information by irradiating a laser beam having a wavelength of 440 nm or less on a substrate, and the recording layer independently contains two or more dye residues in the molecule. An optical information recording medium comprising a dye having a group and having these dye residues bonded together without a conjugated bond.

  The recording layer has two or more dye residues independently in the molecule, and contains a dye formed by bonding these dye residues without a conjugated bond. The information can be recorded and reproduced at high density, and the optical storage stability can be improved. This is considered to be due to suppression of dye association per unit volume.

  It is preferable that at least one of the following first to eighth aspects is applied to the optical information recording medium of the present invention.

(1) A 1st aspect is an aspect whose said pigment | dye is a structure represented by following General formula (1).

General formula (1)

(In General Formula (1), Dye ¹¹ , Dye ¹² , and Dye ^2k represent dye residues, and L ¹¹ and L ^2k are divalent that do not form a π-conjugated conjugate bond between the dye residues to which they are bonded. Represents a linking group, n represents an integer of 0 or more and 10 or less, k represents an integer of 0 or more and n or less, Q represents an ion for neutralizing electric charge, and y is necessary for neutralization of electric charge. Represents a number.)

  Since the dye has a structure represented by the general formula (1), dye association per unit volume is suppressed, and light fastness can be improved.

(2) In the second aspect, the dye residue is an oxonol dye residue. In general, the multimerizing dye is hardly soluble in the solvent, but the oxonol dye residue can increase the solubility in fluoroalcohol.

(3) In the third aspect, the dye is the following general formula (2-1), the following general formula (2-2), the following general formula (2-3), the following general formula (2-4), and the following It is an embodiment represented by any one of the general formula (2-5).

(In the above general formulas (2-1), (2-2), (2-3), (2-4), and (2-5), R represents a substituent on the methine carbon, and m is 0. Represents an integer of 1 to n, n represents an integer of 0 to 2m + 1, and when n is an integer of 2 or more, a plurality of Rs may be the same or different from each other, and are connected to each other to form a ring. at ^best, Za ^5, Za ⁶ is a group of atoms forming an acidic ^{nucleus, L 11, Q,} definition of y ^L 11 in the general formula (1), Q, are the same as y, Y is -O -Or -NR ¹ -or -CR ² R ^3- , R ^{1 to} R ⁹ each independently represents a hydrogen atom or a substituent, Z represents a substituted or unsubstituted alkylene group, and x represents Represents 1 or 2. G represents an oxygen atom or a sulfur atom.)

  The general formula (2-1), the general formula (2-2), the general formula (2-3), the general formula (2-4), and the general formula (2-5) are degradable. Since it is good, good recording can be made possible.

(4) The fourth aspect is the above general formula (2-1), general formula (2-2), general formula (2-3), general formula (2-4), and general formula (2-5). In this embodiment, m is 0. When m is 0, an effect that high light stability can be obtained as compared with when m is 1 or more is obtained. This is thought to be because when m is 0, the conjugated chain is three-dimensionally complicated and it is difficult to add singlet oxygen.

(5) In a fifth aspect, the dye is the following general formula (5-1), the following general formula (5-2), the following general formula (5-3), the following general formula (5-4), and the following This is an oxonol dye represented by the general formula (5-5).

(In the general formula (5-1), the general formula (5-2), the general formula (5-3), the general formula (5-4), and the general formula (5-5), R, The definitions of Z, Y, Q, and y are the same as R, Z, Y, Q, and y in formulas (2-1) to (2-5), and R ^{1 to} R ⁹ are each independently a hydrogen atom or Represents a substituent, G represents an oxygen atom or a sulfur atom, and x is 1 or 2.)

  The general formula (5-1), the general formula (5-2), the general formula (5-3), the general formula (5-4), and the general formula (5-5) are decomposable. Since it is good, good recording can be made possible.

(6) The sixth aspect is an aspect in which a light reflecting layer made of metal is provided separately from the recording layer. By providing the light reflection layer, it is possible to improve the reflectance during information reproduction.
(7) The seventh aspect is an aspect in which a protective layer is provided separately from the recording layer. By providing the protective layer, various layers can be protected.
(8) The substrate is a transparent disk-shaped substrate having a pregroove with a track pitch of 50 to 600 nm on the surface, and the recording layer is provided on the surface side on which the pregroove is formed. With such a configuration, high-density recording of information can be performed more reliably.

  The present invention is also an information recording method characterized in that information is recorded by irradiating the above-described optical information recording medium of the present invention with a laser beam having a wavelength of 440 nm or less. According to the information recording method of the present invention, since the above-described optical information recording medium of the present invention is used, high-density recording and reproduction of information can be performed satisfactorily.

  According to the present invention, high-density recording and reproduction of information performed by laser light irradiation of 440 nm or less can be satisfactorily performed, and the optical information recording medium having good optical storage stability and information recording on the optical information recording medium A method can be provided.

[1] Optical information recording medium The optical information recording medium of the present invention is an optical information recording medium having a recording layer capable of recording information by irradiating a laser beam having a wavelength of 440 nm or less on a substrate. It contains a dye having two or more dye residues independently within each other, and these dye residues are bonded via a conjugate bond. Here, the dye residue refers to a group having a structure in which one hydrogen atom in a structural formula showing a dye is extracted and can be bonded to another compound.

  The optical information recording medium of the present invention will be described in detail below. In the present invention, when a specific moiety is referred to as a “group”, unless otherwise specified, it may be substituted with one or more (up to the maximum possible) substituents. It means that it is not necessary.

  For example, “alkyl group” means a substituted or unsubstituted alkyl group. Moreover, the substituent which can be used for the compound in the present invention may be any substituent regardless of the presence or absence of substitution. Furthermore, in the present invention, when a specific moiety is referred to as “ring”, or when “ring” is included in “group”, it may be monocyclic or condensed unless otherwise specified. May not be substituted. For example, the “aryl group” may be a phenyl group, a naphthyl group, or a substituted phenyl group.

The dye is preferably a structure represented by the following general formula (1). In the following general formula (1), Dye ¹¹ , Dye ¹² , and Dye ^2k each independently represent a dye residue. Any dye forming the dye residue represented by Dye ¹¹ , Dye ¹² , and Dye ^2k may be used. For example, cyanine dye, styryl dye, merocyanine dye, phthalocyanine dye, oxonol dye, azo dye, azamethine dye, Residues of squalium dyes and metal chelate complex dyes may be mentioned. Among these, those that form dye residues represented by Dye ¹¹ , Dye ¹² , and Dye ^2k are preferably cyanine dyes, merocyanine dyes, oxonol dyes, phthalocyanine dyes, and metal chelate dye residues. More preferably, the dye residue represented by Dye ¹¹ , Dye ¹² , or Dye ^2k is any one of a cyanine dye, a merocyanine dye, and an oxonol dye, and a cyanine dye or an oxonol dye is most preferable. The dye residues represented by Dye ¹¹ , Dye ¹² , and Dye ^2k may be different or the same, but are preferably the same. L ¹¹ and L ^2k represent a divalent linking group that does not form a π-conjugated system bond between the dye residues to which they are bonded, n represents an integer of 0 or more and 10 or less, k is 0 or more and n or less Q represents an ion that neutralizes charge, and y represents a number necessary for charge neutralization.

General formula (1)

When the dye residue represented by Dye ¹¹ , Dye ¹² , or Dye ^2k is a cyanine dye residue, the cyanine dye represented by the following general formula (2) is preferable as the cyanine dye serving as the residue.

"General formula (2)"

In the general formula (2), Za ¹ and Za ² each represent an atomic group forming a 5-membered or 6-membered nitrogen-containing heterocycle, and these further include a benzene ring, a benzofuran ring, a pyridine ring, a pyrrole ring, an indole ring, It may be condensed with a thiophene ring or the like.

Ra ¹ and Ra ² are each a hydrogen atom, a substituted or unsubstituted alkyl group (preferably having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, benzyl, 3 -Sulfopropyl, 4-sulfobutyl, 3-methyl-3-sulfopropyl, 2'-sulfobenzyl, carboxymethyl, 5-carboxypentyl), a substituted or unsubstituted alkenyl group (preferably having 2 to 20 carbon atoms, for example, Vinyl, allyl), substituted or unsubstituted aryl group (preferably having 6 to 20 carbon atoms, such as phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), substituted or unsubstituted hetero A cyclic group (preferably having 1 to 20 carbon atoms such as pyridyl, thienyl, furyl, thiazolyl, imidazolyl) Pyrazolyl, pyrrolidino, piperidino, morpholino), preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted sulfoalkyl group, more preferably a substituted or unsubstituted alkyl group or substituted or unsubstituted Represents a sulfoalkyl group. Ma ^{1 to} Ma ⁷ each independently represents a methine group and may have a substituent, and the substituent is preferably an alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, i-propyl), Halogen atom (for example, chlorine, bromine, iodine, fluorine), nitro group, C1-C20 alkoxy group (for example, methoxy, ethoxy), C6-C26 aryl group (for example, phenyl, 2-naphthyl) , A heterocyclic group having 0 to 20 carbon atoms (for example, 2-pyridyl, 3-pyridyl), an aryloxy group having 6 to 20 carbon atoms (for example, phenoxy, 1-naphthoxy, 2-naphthoxy), 1 to 20 carbon atoms Acylamino group (for example, acetylamino, benzoylamino), carbamoyl group having 1 to 20 carbon atoms (for example, N, N-dimethylcarbamoyl), sulfo group, hydro Shi group, a carboxy group, an alkylthio group having 1 to 20 carbon atoms (e.g., methylthio) and a cyano group. Further, it may form a ring with another methine group, or can form a ring with an auxiliary color group.

Ma ^{1 to} Ma ⁷ are preferably unsubstituted, ethyl group-substituted, or methyl group-substituted methine groups. na ¹ and na ² are 0 or 1, preferably 0. ka ¹ represents an integer from 0 to 3. Preferably it is an integer from 0 to 2, more preferably 0. When ka ¹ is 2 or more, Ma ³ and Ma ⁴ may be the same or different. Q represents an ion for neutralizing the charge, and y represents a number necessary for neutralizing the charge.

In general formula (2), Za ¹ , Za ² , Ra ¹ , Ra ² and any one of hydrogen atoms constituting Ma ^{1 to} Ma ⁷ are removed and linked as a dye residue of general formula (1). It can be combined with the groups L ¹¹ , L ^2k .

Dye ^{11, Dye} 12, if to form a dye residue represented by ^{Dye 2k} is merocyanine dye residue, a merocyanine dye as a residue, merocyanine dye is preferably represented by the following general formula (3) .

"General formula (3)"

In the general formula (3), Za ³ represents a group of atoms forming a 5-membered or 6-membered nitrogen-containing heterocyclic ring, which further includes a benzene ring, a benzofuran ring, a pyridine ring, a pyrrole ring, an indole ring, a thiophene ring, etc. It may be condensed with. Za ⁴ represents an atomic group forming an acidic nucleus. Ra ³ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group (the preferred examples are the same as those for Ra ¹ and Ra ² ). Ma ^{8 to} Ma ¹¹ each independently represent a methine group (preferred examples are the same as Ma ¹ to Ma ⁷ ). na ³ is 0 or 1. ka ² represents an integer of 0 to 3, preferably an integer of 0 to 2. Q represents an ion for neutralizing the charge, and y represents a number necessary for neutralizing the charge. When ka ² is 2 or more, Ma ¹⁰ and Ma ¹¹ may be the same or different. In the general formula (3), any hydrogen atom constituting Za ³ , Za ⁴ , Ra ³ , Ma ^{8 to} Ma ¹¹ is removed, and the linking group L is used as the dye residue of the general formula (1). Can be combined.

The case where an oxonol dye residue is the one that forms the dye residue represented by Dye ¹¹ , Dye ¹² , or Dye ^2k will be described. In the present invention, the oxonol dye is defined as a polymethine dye having an anionic dye. An oxonol dye represented by the following general formula (I) is particularly preferably used from the viewpoint of excellent recording characteristics.

  In general formula (I), A, B, C, and D represent an electron-withdrawing group, and “A and B” or “C and D” may be connected to each other to form a ring, and are not bonded to each other. In this case, the sum of the A and B Hammett σp values and the sum of the C and D Hammett σp values are each 0.6 or more. R represents a substituent on the methine carbon, m represents an integer of 0 to 3, n represents an integer of 0 to 2m + 1, and when n is an integer of 2 or more, a plurality of Rs may be the same or different from each other. They may be linked to each other to form a ring, Q represents an ion for neutralizing the charge, and y represents a number necessary for neutralizing the charge.

  The general formula (I) includes a plurality of tautomers due to differences in the notation of the local position of the anion. In particular, any of A, B, C, and D is -CO-E (E is a substituent). In some cases, it is common to describe a localized negative charge on an oxygen atom. For example, when D is -CO-E, the following general formula (II) is general, and such a description is also included in general formula (I).

  The definitions of A, B, C, R, m, n, Q, and y in the general formula (II) are the same as those in the general formula (I).

  Hereinafter, the oxonol dye represented by the general formula (I) will be described. In the general formula (I), A, B, C and D represent an electron-withdrawing group, and A and B or C and D may be connected to each other to form a ring. And the sum of the Hammett σp values of B and B and the sum of the Hammett σp values of C and D are 0.6 or more, respectively. A, B, C and D may be the same or different. The Hammett substituent constant σp value of the electron-withdrawing group represented by A, B, C and D is preferably independently in the range of 0.30 to 0.85, more preferably 0.35. It is in the range of ~ 0.80.

  Hammett's substituent constant σp value (hereinafter referred to as σp value) is described in, for example, Chem. Rev. 91, 165 (1991) and references cited therein, and those not described can be obtained by the method described in the same document. When A and B (C and D) are connected to form a ring, the σp value of A (C) means the σp value of the group -A-B-H (-C-D-H). , B (D) σp value means the σp value of the group -BAH (-DCH). In this case, both have different σp values because of different coupling directions.

  Preferable specific examples of the electron-withdrawing group represented by A, B, C and D include a cyano group, a nitro group, and an acyl group having 1 to 10 carbon atoms (eg, acetyl, propionyl, butyryl, pivaloyl, benzoyl). An alkoxycarbonyl group having 2 to 12 carbon atoms (eg, methoxycarbonyl, ethoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, decyloxycarbonyl), an aryloxycarbonyl group having 7 to 11 carbon atoms (eg, phenoxycarbonyl), A carbamoyl group having 1 to 10 carbon atoms (eg, methylcarbamoyl, ethylcarbamoyl, phenylcarbamoyl), an alkylsulfonyl group having 1 to 10 carbon atoms (eg, methanesulfonyl), an arylsulfonyl group having 6 to 10 carbon atoms ( Example: benzenesulfonyl), charcoal An alkoxysulfonyl group having 1 to 10 atoms (eg, methoxysulfonyl), a sulfamoyl group having 1 to 10 carbon atoms (eg, ethylsulfamoyl, phenylsulfamoyl), an alkylsulfinyl group having 1 to 10 carbon atoms ( Examples, methanesulfinyl, ethanesulfinyl), arylsulfinyl groups having 6 to 10 carbon atoms (eg, benzenesulfinyl), alkylsulfenyl groups having 1 to 10 carbon atoms (eg, methanesulfenyl, ethanesulfenyl), carbon Arylsulfenyl group having 6 to 10 atoms (eg, benzenesulfenyl), halogen atom, alkynyl group having 2 to 10 carbon atoms (eg, ethynyl), diacylamino group having 2 to 10 carbon atoms (eg, diacetyl) Amino), phosphoryl group, carboxyl group, 5-membered or Membered heterocyclic group (for example, 2-benzothiazolyl, 2-benzoxazolyl, 3-pyridyl, 5- (1H) -tetrazolyl, 4-pyrimidyl), preferably cyano group, alkoxycarbonyl group, alkylsulfonyl group And an arylsulfonyl group.

  In the general formula (I), examples of the substituent on the methine carbon represented by R include those described below. A linear or cyclic alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, n-propyl, isopropyl, n-butyl), a substituted or unsubstituted aryl group having 6 to 18 carbon atoms (for example, phenyl) , Chlorophenyl, anisyl, toluyl, 2,4-di-t-amyl, 1-naphthyl), alkenyl group (for example, vinyl, 2-methylvinyl), alkynyl group (for example, ethynyl, 2-methylethynyl, 2-phenyl) Ethynyl), halogen atom (eg, F, Cl, Br, I), cyano group, hydroxyl group, carboxyl group, acyl group (eg, acetyl, benzoyl, salicyloyl, pivaloyl), alkoxy group (eg, methoxy, butoxy, cyclohexyl) Oxy), aryloxy groups (eg, phenoxy, 1-naphthoxy), alkylthio Group (e.g., methylthio, butylthio, benzylthio, 3-methoxypropylthio), an arylthio group (e.g., phenylthio, 4-chlorophenylthio)

An alkylsulfonyl group (for example, methanesulfonyl, butanesulfonyl), an arylsulfonyl group (for example, benzenesulfonyl, paratoluenesulfonyl), a carbamoyl group having 1 to 10 carbon atoms, an amide group having 1 to 10 carbon atoms, and the number of carbon atoms 2-12 imide groups, C2-C10 acyloxy groups, C2-C10 alkoxycarbonyl groups, heterocyclic groups (e.g., pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl and other heteroaromatics) Ring, pyrrolidine ring, piperidine ring, morpholine ring, pyran ring, thiopyran ring, dioxane ring, dithiolane ring and other aliphatic heterocycles).

  R is preferably a halogen atom, a linear or cyclic alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or 6 to 10 carbon atoms. An aryloxy group, a heterocyclic group having 3 to 10 carbon atoms, particularly a chlorine atom, an alkyl group having 1 to 4 carbon atoms (eg, methyl, ethyl, isopropyl), phenyl, 1 to 4 carbon atoms Alkoxy groups (eg, methoxy, ethoxy), phenoxy, and nitrogen-containing heterocyclic groups having 4 to 8 carbon atoms (eg, 4-pyridyl, benzoxazol-2-yl, benzothiazol-2-yl) are preferable.

  n represents an integer of 0 to 2m + 1. When n is an integer of 2 or more, a plurality of Rs may be the same as or different from each other, and may be connected to each other to form a ring. At this time, the number of ring members is preferably 4 to 8, particularly preferably 5 or 6, and the constituent atoms of the ring are preferably carbon atoms, oxygen atoms or nitrogen atoms, and particularly preferably carbon atoms.

  A, B, C, D and R may further have a substituent, and examples of the substituent include those mentioned above as examples of the monovalent substituent represented by R in formula (I). The same thing can be mentioned.

  As the dye used for the optical disk, it is preferable that A and B or C and D are connected to form a ring from the viewpoint of thermal decomposability. Examples of such a ring include the following (A-1 To A-66). In the examples, Ra, Rb and Rc each independently represent a hydrogen atom or a substituent.

  Preferred rings among the above are A-2, A-8, A-9, A-10, A-13, A-14, A-16, A-17, A-36, A-39, A-. 42, A-54, A-57, A-59, A-61, A-65 and A-66. More preferably, A-2, A-9, A-10, A-13, A-17, A-42, A-54, A-57, A-59, A-61, A-65 and A- 66. Most preferred are those represented by A-13, A-17, A-54, A-57, A-59, A-61, A-65 and A-66.

  The substituents represented by Ra, Rb and Rc have the same meanings as those exemplified as the substituent represented by R. Ra, Rb and Rc may be connected to each other to form a carbocyclic or heterocyclic ring. Examples of the carbocycle include saturated or unsaturated 4- to 7-membered carbocycles such as a cyclohexyl ring, cyclopentyl ring, cyclohexene ring, and benzene ring. Examples of the heterocyclic ring include saturated or unsaturated 4- to 7-membered heterocyclic rings such as piperidine ring, piperazine ring, morpholine ring, tetrahydrofuran ring, furan ring, thiophene ring, pyridine ring, and pyrazine ring. it can. These carbocycles or heterocycles may be further substituted. Further, the group that can be substituted has the same meaning as the substituents represented by R.

  In the general formula (I), m is an integer of 0 to 3, and the absorption wavelength of the oxonol dye varies greatly depending on the value of m. Although it is necessary to design a dye having an optimum absorption wavelength according to the oscillation wavelength of the laser used for recording and reproduction, the selection of the value of m is important in this respect. When the central oscillation wavelength of the laser used for recording / reproduction is 780 nm (semiconductor laser for CD-R recording), in the general formula (I), m is preferably 2 or 3, and when the central oscillation wavelength is 635 nm or 650 nm (DVD- R is a semiconductor laser for recording, and m is preferably 1 or 2, and m is preferably 0 or 1 when the center oscillation wavelength is 550 nm or less (for example, a blue-violet semiconductor laser having a center oscillation wavelength of 405 nm).

  The oxonol chromophore represented by the general formula (I) may be bonded at an arbitrary position to form a multimer. In this case, each unit may be the same as or different from each other. You may couple | bond with polymer chains, such as a methacrylate, polyvinyl alcohol, and a cellulose.

In the general formula (I), any one of the hydrogen atoms constituting A, B, C, D, and R is removed and combined with the linking groups L ¹¹ and L ^2k as the dye residue of the general formula (1). Can do.

  Specific examples of the cyanine dye, merocyanine dye and oxonol dye include F.I. M.M. As described by Harmer, Heterocyclic Compounds-Cyanine Dies and Related Compounds, John & Wiley & Sons, New York, London, 1964.

  The methine dye is represented by any one of General Formula (2-1), General Formula (2-2), General Formula (2-3), General Formula (2-4), and General Formula (2-5). Oxonol dyes are preferred.

In the above general formula (2-1), general formula (2-2), general formula (2-3), general formula (2-4), and general formula (2-5), R is on methine carbon. Wherein m represents an integer of 0 to 1, n represents an integer of 0 to 2m + 1, and when n is an integer of 2 or more, a plurality of Rs may be the same or different from each other; may form a ring ^together, Za ^5, Za ⁶ is a group of atoms forming an acidic ^{nucleus, L 11, Q, L} 11 of the definition of y the general formula (1), Q, y Y is —O— or —NR ¹ — or —CR ² R ³ —, each of R ^{1 to} R ⁹ independently represents a hydrogen atom or a substituent, and Z is substituted or unsubstituted. Represents a substituted alkylene group, and x represents 1 or 2; G represents an oxygen atom or a sulfur atom, and is preferably an oxygen atom.

Moreover, it does not specifically limit as a substituent represented by R < ¹ > -R < ⁹ >, The same thing as the substituent represented by R in General formula (I) is mentioned, A preferable range is also the same. Z represents a substituted or unsubstituted alkylene group. Preferred examples of the alkylene group include a substituted or unsubstituted methylene group, a substituted or unsubstituted ethylene group, and a substituted or unsubstituted propylene group, and more preferably a substituted or unsubstituted methylene group, a substituted or unsubstituted group. An ethylene group, more preferably a substituted or unsubstituted methylene group.

  In the general formula (2-1), the general formula (2-2), the general formula (2-3), the general formula (2-4), and m in the general formula (2-5), 0 is preferred.

  Among the dyes represented by the general formula (1), the following general formula (5-1), the following general formula (5-2), the following general formula (5-3), the following general formula (5-4), and An optical information recording medium containing a dye having a structure represented by the following general formula (5-5) is preferred.

In the general formula (5-1), the general formula (5-2), the general formula (5-3), the general formula (5-4), and the general formula (5-5), R ¹ to The definitions of R ⁹ , R, Y, Z, Q, y, and G are the same as those in the general formulas (2-1), (2-2), (2-3), (2-4), and (2-5). It is. x is 1 or 2.

Za ¹ , Za ² and Za ³ are oxazole nuclei having 3 to 25 carbon atoms (for example, 2-3-methyloxazolyl, 2-3-ethyloxazolyl, 2-3,4-diethyloxazolyl, 2-3-methylbenzoxazolyl, 2-3-ethylbenzoxazolyl, 2-3-sulfoethylbenzoxazolyl, 2-3-sulfopropylbenzoxazolyl, 2-3-methylthioethylbenzox Zolyl, 2-3-methoxyethylbenzoxazolyl, 2-3-sulfobutylbenzoxazolyl, 2-3-methyl-β-naphthoxazolyl, 2-3-methyl-α-naphthoxazolyl 2-3-sulfopropyl-β-naphthoxazolyl, 2-3-sulfopropyl-β-naphthoxazolyl, 2-3- (3-naphthoxyethyl) benzoxazolyl, -3,5-dimethylbenzoxazolyl, 2-6-chloro-3-methylbenzoxazolyl, 2-5-bromo-3-methylbenzoxazolyl, 2-3-ethyl-5-methoxybenzoxal Zolyl, 2-5-phenyl-3-sulfopropylbenzoxazolyl, 2-5- (4-bromophenyl) -3-sulfobutylbenzoxazolyl,

2-3-dimethyl-5,6-dimethylthiobenzoxazolyl), thiazole nucleus having 3 to 25 carbon atoms (for example, 2-3 methylthiazolyl, 2-3-ethylthiazolyl, 2-3-sulfopropylthiazolyl) , 2-3-sulfobutylthiazolyl, 2-3,4-dimethylthiazolyl, 2-3,4,4-trimethylthiazolyl, 2-3-carboxyethylthiazolyl, 2-3-methyl Benzothiazolyl, 2-3-ethylbenzothiazolyl, 2-3-butylbenzothiazolyl, 2-3-sulfopropylbenzothiazolyl, 2-3-sulfobutylbenzothiazolyl, 2-3 -Methyl-β-naphthothiazolyl, 2-3-sulfopropyl-γ-naphthothiazolyl, 2-3- (1-naphthoxyethyl) benzothiazolyl, 2-3,5-dimethylbenzothiazolyl, 2-6-chloro-3-methylbenzothiazolyl, 2-6-iodo-3-ethylbenzothiazolyl, 2-5-bromo-3-methylbenzothiazolyl, 2-3-ethyl-5 Methoxybenzothiazolyl, 2-5-phenyl-3-sulfopropylbenzothiazolyl, 2-5- (4-bromophenyl) -3-sulfobutylbenzothiazolyl, 2-3-dimethyl-5,6 -Dimethylthiobenzothiazolyl, etc.), imidazole nucleus having 3 to 25 carbon atoms (for example, 2-1,3-diethylimidazolyl, 2-1,3-dimethylimidazolyl, 2-1-methylbenzimidazolyl, 2 -1,3,4-triethylimidazolyl, 2-1,3-diethylbenzimidazolyl, 2-1,3,5-trimethylbenzimidazolyl, 2-6-chloro-1,3-di Chill benzimidazolyl, 2-5,6- dichloro-1,3-diethyl-benzimidazolyl, 2-1,3- and di-sulfopropyl-5-cyano-6-chloro-benzimidazolyl and the like),

C10-30 indolenine nucleus (for example, 3,3-dimethylindolenine), C9-25 quinoline nucleus (for example, 2-1-methylquinolyl, 2-1-ethylquinolyl, 2-1-methyl-6) -Chloroquinolyl, 2-1,3-diethylquinolyl, 2-1-methyl-6-methylthioquinolyl, 2-1-sulfopropylquinolyl, 4-1-methylquinolyl, 4-1-sulfoethylquinolyl, 4 -1-methyl-7-chloroquinolyl, 4-1,8-diethylquinolyl, 4-1-methyl-6-methylthioquinolyl, 4-1-sulfopropylquinolyl, etc.), C 3-25 Selenazole nucleus (for example, 2-3-3-methylbenzoselenazolyl and the like), pyridine nucleus having 5 to 25 carbon atoms (for example, 2-pyridyl and the like) and the like In addition, thiazoline nucleus, oxazoline nucleus, selenazoline nucleus, tellurazoline nucleus, tellurazole nucleus, benzotelrazole nucleus, imidazoline nucleus, imidazo [4,5-quinoxaline] nucleus, oxadiazole nucleus, thiadiazole nucleus, tetrazole nucleus, Mention may be made of pyrimidine nuclei.

  These may be substituted. As the substituent, for example, an alkyl group (for example, methyl, ethyl, propyl), a halogen atom (for example, chlorine, bromine, iodine, fluorine), a nitro group, an alkoxy group (for example, methoxy, ethoxy) ), An aryl group (eg, phenyl), a heterocyclic group (eg, 2-pyridyl, 3-pyridyl, 1-pyrrolyl, 2-thienyl), an aryloxy group (eg, phenoxy), an acylamino group (eg, acetylamino, benzoylamino) ), Carbamoyl group (for example, N, N-dimethylcarbamoyl), sulfo group, sulfonamide group (for example, methanesulfonamide), sulfamoyl group (for example, N-methylsulfamoyl), hydroxy group, carboxy group, alkylthio group (for example, methylthio group) ), Cyano group, etc. Details, oxazole nucleus, an imidazole nucleus, a thiazole nucleus. These heterocycles may be further condensed. Examples of the condensed ring include a benzene ring, a benzofuran ring, a pyridine ring, a pyrrole ring, an indole ring, and a thiophene ring.

Za ⁴ , Za ⁵ and Za ⁶ each represent a group of atoms necessary to form an acidic nucleus, and are defined by James, The Theory of the Photographic Process, 4th edition, Macmillan, 1977, p. 198. The Specifically, 2-pyrazolone-5-one, pyrazolidine-3,5-dione, imidazolin-5-one, hydantoin, 2 or 4-thiohydantoin, 2-iminooxazolidine-4-one, 2-oxazoline-5 -One, 2-thiooxazoline-2,4-dione, isorhodanine, rhodanine, indan-1,3-dione, thiophen-3-one, thiophen-3-one-1,1-dioxide, indoline-2-one, Indoline-3-one, 2-oxoindazolium, 5,7-dioxo-6,7-dihydrothiazolo [3,2-a] pyrimidine, 3,4-dihydroisoquinolin-4-one, 1,3- Dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, coumarin-2,4-dione, indazolin-2-one, pyrido Nuclei such as 1,2-a] pyrimidine-1,3-dione, pyrazolo [1,5-b] quinazolone, pyrazolopyridone, 3-dicyanomethylidenyl-3-phenylpropionitrile, oxathiolanone dioxide, meldrum acid, etc. Preferred are 2-pyrazolone-5-one, barbituric acid, 2-thiobarbituric acid, oxathiolanone dioxide, meldrum acid, and pyrazolidine-3,5-dione.

In the general formula (1), L ¹¹ and L ^2k each independently represent a divalent linking group, and there is no particular limitation except that a π-conjugated system is not formed between the chromophores to which they are bonded. Group (C1-C20, for example, methylene, ethylene, propylene, butylene, pentylene), arylene group (C6-C26, for example, phenylene, naphthylene), alkenylene group (C2-C20, for example, ethenylene, propenylene) , Alkynylene group (having 2 to 20 carbon atoms, for example, ethynylene, propynylene), metallocenylene group (for example, ferrocene), —CO—N (R ¹⁰¹ ) —, —CO—O—, —SO ₂ —N (R ¹⁰² ) —, _{^{-SO 2 -O -, - N (}} R 103) -CO-N (R 104) -, - SO 2 -, - SO -, - S -, - O -, - CO -, - N ^{(R 105)} -, heterylene group (carbon number 1 to 26, for example 6-chloro-1,3,5-triazyl-2,4-diyl group, pyrimidine-2,4-diyl group) one or more of A linking group having a carbon number of 0 to 100 or less, preferably 1 or more and 20 or less, formed in combination. R ¹⁰¹ , R ¹⁰² , R ¹⁰³ , R ¹⁰⁴ , and R ¹⁰⁵ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. In addition, one or more linking groups represented by L ¹¹ and L ^2k may exist between two chromophores to which they are linked, and a plurality (preferably two) are bonded to form a ring. It may be formed. L ¹¹ and L ^2k are each preferably formed by bonding two alkylene groups (preferably ethylene) to form a ring. Among them, the case where a 5- or 6-membered ring (preferably cyclohexyl) is formed is more preferable.

  In the general formula (1), n represents an integer of 0 or more and 10 or less, preferably an integer of 0 to 5, more preferably an integer of 0 to 3, and particularly preferably an integer of 0 to 2.

In the general formula (1), k represents all integers of 0 or more and n or less. For example, when n is 2, k represents three integers of 0, 1, and ^2, and Dye ^2k and L ^2k are independently Dye ²⁰ , Dye ²¹ , Dye ²² chromophore and L ²⁰ , L ²¹ , L ²² linking groups are represented. When n represents an integer of 2 or more, the plurality of Dye ^2k may be the same or different from each other. When n represents an integer of 2 or more, the plurality of L2k may be the same or different from each other.

  In the general formula (1), Q represents an ion for neutralizing the charge, and y represents a number necessary for neutralizing the charge. Whether a compound is a cation, an anion, or has a net ionic charge depends on the substituent of the compound. In general formulas (1) and (3) to (5), the ion represented by Q may represent a cation or an anion depending on the charge of the dye molecule, and may represent a dye molecule. Q is not present when is uncharged. There is no restriction | limiting in particular in the ion represented as Q, The ion which consists of an inorganic compound may be sufficient as the ion which consists of an organic compound. Further, the charge of ions represented as Q may be monovalent or multivalent. Examples of the cation represented by Q include metal ions such as sodium ion and potassium ion, quaternary ammonium ion, oxonium ion, sulfonium ion, phosphonium ion, selenonium ion, and onium ion such as iodonium ion. . On the other hand, examples of the anion represented by Q include halogen anions such as chloride ion, bromide ion and fluoride ion, heteropoly acid ions such as sulfate ion, phosphate ion and hydrogen phosphate ion, and oxalate ion. And organic polyvalent anions such as maleate ion, fumarate ion and aromatic disulfonate ion, tetrafluoroborate ion and hexafluorophosphate ion.

  The cation represented by Q is preferably an onium ion, and more preferably a quaternary ammonium ion. Of the quaternary ammonium ions, 4,4′-bipyridinium cation represented by general formula (I-4) in JP-A No. 2000-52658 and JP-A No. 2002-59652 are particularly preferable. 4,4′-bipyridinium cation.

  The anions represented by Q are preferably tetrafluoroborate ions, hexafluorophosphate ions and organic polyvalent anions, and more preferably divalent or trivalent organic compounds such as naphthalenedisulfonic acid derivatives. Anion. Of the divalent and trivalent organic anions, naphthalenedisulfonate anion disclosed in JP-A-10-226170 is particularly preferable.

  Among the dyes represented by the general formula (1), the following general formula (2-1), the following general formula (2-2), the following general formula (2-3), the following general formula (2-4), and the following A dye having a structure represented by any one of the general formula (2-5) is preferable.

The general formula (2-1), the general formula (2-2), and the general formula (2-3) will be described. Y represents either —O— or —NR ¹ — or —CR ² R ³ —. Y is preferably —O— or —CR ² R ³ —, and more preferably —O—.

R ^{1 to} R ⁹ each independently represents a hydrogen atom or a substituent. No particular limitation is imposed on the substituent represented by R ¹ to R ^9, but general formula (I) the same as the substituent represented by R are exemplified in, the preferred range is also the same.

  Z represents a substituted or unsubstituted alkylene group. Preferred examples of the alkylene group include a substituted or unsubstituted methylene group, a substituted or unsubstituted ethylene group, and a substituted or unsubstituted propylene group, and more preferably a substituted or unsubstituted methylene group, a substituted or unsubstituted group. An ethylene group, more preferably a substituted or unsubstituted methylene group.

  x represents 1 or 2, and is preferably 2.

  G represents an oxygen atom or a sulfur atom, and is preferably an oxygen atom.

The general formula (2-1), the general formula (2-2), the general formula (2-3), the general formula (2-4) and the general formula ^(2-5), Za 5, Za ⁶ is a group of atoms forming an acidic ^{nucleus, L 11, Q,} definition of y is ^L 11, Q, same y in formula (1).

  Among the structures represented by the above general formulas (2-1), (2-2), (2-3), (2-4), and (2-5), a dye in which m is 0 is most preferable.

  Of the dyes represented by the above general formula (2-1), the above general formula (2-2), the above general formula (2-3), the above general formula (2-4) and the above general formula (2-5) Among these, from the viewpoint of high light stability and good decomposability, any one of the following general formulas (5-1), (5-2), (5-3), (5-4), and (5-5) A dye having a structure represented by the formula is most preferred.

In the general formulas (5-1), (5-2), (5-3), (5-4), and (5-5), R ^{1 to} R ⁹ , R, Y, Z, Q, y, The definition of G is the same as the general formulas (2-1), (2-2), (2-3), (2-4), and (2-5). x is 1 or 2.

  Preferred specific examples (S-1 to S-27) of the compounds represented by the general formulas (1) and (2) according to the present invention are listed below, but the present invention is not limited thereto.

  Preferred specific compounds used in the present invention are shown in Table 1 below.

  The dye compound represented by the general formula (1) according to the present invention may be used alone or in combination of two or more. Moreover, you may use together the pigment compound concerning this invention, and the pigment compound other than this.

  The recording layer of the information recording medium of the present invention can contain various anti-fading agents in order to improve the light resistance of the recording layer. Examples of the antifading agent include organic oxidants and singlet oxygen quenchers. As the organic oxidizing agent used as the anti-fading agent, compounds described in JP-A-10-151861 are preferable. As the singlet oxygen quencher, those described in publications such as known patent specifications can be used. Specific examples thereof include JP-A Nos. 58-175893, 59-81194, 60-18387, 60-19586, 60-19586, 60-35054, 60-36190, 60-36191, 60-44554, 60-44555, 60-44389, 60-44390, 60-54892, 60-47069, 63-20995, JP Listed in publications such as Nos. 4-25492, 1-38680, and 6-26028, German Patent No. 350399, and the Chemical Society of Japan, October 1992, page 1141 Can do. Examples of preferable singlet oxygen quenchers include compounds represented by the following general formula (II).

"General Formula (II)"

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 is preferably an unsubstituted alkyl group having 1 to 6 carbon atoms. Examples of the substituent for the alkyl group include a halogen atom (eg, F, Cl), an alkoxy group (eg, methoxy, ethoxy), an alkylthio group (eg, methylthio, ethylthio), an acyl group (eg, acetyl, propionyl), an acyloxy group (Eg, acetoxy, propionyloxy), hydroxy group, alkoxycarbonyl group (eg, methoxycarbonyl, ethoxycarbonyl), alkenyl group (eg, vinyl), aryl group (eg, phenyl, naphthyl). Among these, a halogen atom, an alkoxy group, an alkylthio group, and an alkoxycarbonyl group are preferable. Preferred examples of the Q ⁻ anion include ClO ₄ ⁻ , AsF ₆ ⁻ , BF ₄ ⁻ , and SbF ₆ ⁻ .

Examples of compounds represented by general formula (II) (compound numbers II-1 to II-8) are shown in Table 2 below.

  The amount of the antifading agent such as the singlet oxygen quencher used is usually in the range of 0.1 to 50% by weight, preferably in the range of 0.5 to 45% by weight, based on the amount of the dye. Preferably, it is in the range of 3 to 40% by weight, particularly preferably in the range of 5 to 25% by weight.

<Optical information recording media>
The optical information recording medium of the present invention has a mode (1): a write-once recording layer containing a dye on a substrate having a thickness of 0.7 to 2 mm, a cover layer having a thickness of 0.01 to 0.5 mm, Information recording medium or embodiment having the above in order: (2): a write-once recording layer containing a dye on a substrate having a thickness of 0.1 to 1.0 mm, and a protective substrate having a thickness of 0.1 to 1.0 mm And an optical information recording medium having the above in this order. In aspect (1), it is preferable that the track pitch of the pregroove formed on the substrate is 50 to 500 nm, the groove width is 25 to 250 nm, and the groove depth is 5 to 150 nm. In aspect (2), the substrate It is preferable that the track pitch of the pregroove formed is 200 to 600 nm, the groove width is 50 to 300 nm, the groove depth is 30 to 200 nm, and the wobble amplitude is 10 to 50 nm.

  The optical information recording medium of aspect (1) has at least a substrate, a write-once recording layer, and a cover layer. First, members important for these will be described in order.

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

  The track pitch of the pregroove is in the range of 50 to 500 nm, and the upper limit value is preferably 420 nm or less, more preferably 370 nm or less, and further preferably 330 nm or less. Further, the lower limit is preferably 100 nm or more, more preferably 200 nm or more, and further preferably 260 nm or more. If the track pitch is less than 50 nm, it becomes difficult to form the pregroove accurately, and a crosstalk problem may occur. If the track pitch exceeds 500 nm, the recording density may decrease.

  The groove width (half width) of the pregroove is in the range of 25 to 250 nm, the upper limit value is preferably 200 nm or less, more preferably 170 nm or less, and further preferably 150 nm or less. Further, the lower limit is preferably 50 nm or more, more preferably 80 nm or more, and further preferably 100 nm or more. If the groove width of the pregroove is less than 25 nm, the groove may not be sufficiently transferred at the time of molding, or the recording error rate may increase. If it exceeds 250 nm, the pits formed during recording will spread, It may cause crosstalk or a sufficient degree of modulation may not be obtained.

  The groove depth of the pregroove is in the range of 5 to 150 nm, and the upper limit is preferably 100 nm or less, more preferably 70 nm or less, and further preferably 50 nm or less. Further, the lower limit is preferably 10 nm or more, more preferably 20 nm or more, and further preferably 28 nm or more. If the groove depth of the pregroove is less than 5 nm, a sufficient recording modulation degree may not be obtained, and if it exceeds 150 nm, the reflectivity may be significantly lowered.

  In addition, the groove inclination angle of the pregroove is preferably 80 ° or less, more preferably 70 ° or less, still more preferably 60 ° or less, and particularly preferably 50 ° or less. preferable. Further, the lower limit value is preferably 20 ° or more, more preferably 30 ° or more, and further preferably 40 ° or more. If the groove inclination angle of the pregroove is less than 20 °, a sufficient tracking error signal amplitude may not be obtained, and if it exceeds 80 °, molding becomes difficult.

  As the substrate used in the present invention, various materials used as substrate materials for conventional optical information recording media can be arbitrarily selected and used. Specifically, glass; acrylic resin such as polycarbonate and polymethyl methacrylate; vinyl chloride resin such as polyvinyl chloride and vinyl chloride copolymer; epoxy resin; amorphous polyolefin; polyester; metal such as aluminum; These may be used together if desired.

  Among the above materials, thermoplastic resins such as amorphous polyolefin and polycarbonate are preferable, and polycarbonate is particularly preferable from the viewpoints of moisture resistance, dimensional stability, and low price. When these resins are used, the substrate can be manufactured by injection molding. Further, the thickness of the substrate needs to be in the range of 0.7 to 2 mm, preferably in the range of 0.9 to 1.6 mm, and more preferably 1.0 to 1.3 mm. .

  In addition, it is preferable to form an undercoat layer on the substrate surface on the side where a light reflecting layer described later is provided for the purpose of improving the flatness and the adhesive force. Examples of the material for 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 chloro. Polymer materials such as sulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate, etc .; silane coupling Surface modifiers such as agents; The undercoat layer is formed by dissolving or dispersing the above materials in an appropriate solvent to prepare a coating solution, and then applying this 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, and preferably in the range of 0.01 to 10 μm.

[Write-once recording layer of aspect (1)]
The write-once recording layer in a preferred embodiment (1) is a dye (a dye formed by independently having two or more dye residues in the molecule as described above, and these dye residues are bonded without a conjugated bond. ) Is dissolved in a suitable solvent together with a binder, etc. to prepare a coating solution, and then the coating solution is applied on a substrate or a light reflecting layer described later to form a coating film, and then dried. It is formed by. Here, the write-once recording layer may be a single layer or a multilayer. In the case of a multilayer structure, the step of applying the coating liquid is performed a plurality of times. The concentration of the dye in the coating solution is generally in the range of 0.01 to 15% by mass, preferably in the range of 0.1 to 10% by mass, more preferably in the range of 0.5 to 5% by mass, most preferably. It is the range of 0.5-3 mass%.

  Examples of the solvent for the coating solution include esters such as butyl acetate, ethyl lactate and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane and chloroform; dimethylformamide and the like Amides; Hydrocarbons such as methylcyclohexane; Ethers such as tetrahydrofuran, ethyl ether, dioxane; Alcohols such as ethanol, n-propanol, isopropanol, n-butanol diacetone alcohol; 2,2,3,3-tetrafluoropropanol, etc. Fluorinated solvents; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether; That. The above solvents can be used alone or in combination of two or more in consideration of the solubility of the dye used. In the coating solution, various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be added according to the purpose.

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

  The thickness of the write-once recording layer formed in this way is preferably 300 nm or less, more preferably 250 nm or less, and more preferably 200 nm or less on the groove (convex portion in the substrate). More preferably, it is particularly preferably 180 nm or less. The lower limit is preferably 30 nm or more, more preferably 50 nm or more, still more preferably 70 nm or more, and particularly preferably 90 nm or more.

  Further, the thickness of the write-once recording layer is preferably 400 nm or less, more preferably 300 nm or less, and further preferably 250 nm or less on the land (the concave portion in the substrate). The lower limit is preferably 70 nm or more, more preferably 90 nm or more, and further preferably 110 nm or more. Further, the ratio of the thickness of the write-once recording layer on the groove / the thickness of the write-once recording layer on the land is preferably 0.4 or more, more preferably 0.5 or more, and 6 or more is more preferable, and 0.7 or more is particularly preferable. The upper limit is preferably less than 1, more preferably 0.9 or less, still more preferably 0.85 or less, and particularly preferably 0.8 or less.

  When the coating solution contains a binder, examples of the binder include natural organic polymer materials such as gelatin, cellulose derivatives, dextran, rosin, and rubber; hydrocarbon resins such as polyethylene, polypropylene, polystyrene, and polyisobutylene. , Polyvinyl chloride, polyvinylidene chloride, vinyl resins such as polyvinyl chloride / polyvinyl acetate copolymer, acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resin, butyral And synthetic organic polymers such as resins, rubber derivatives, and initial condensates of thermosetting resins such as phenol / formaldehyde resins. When a binder is used in combination as a material for the write-once recording layer, the amount of binder used is generally in the range of 0.01 to 50 times (mass ratio) with respect to the dye, preferably 0.1. It exists in the range of double amount-5 times amount (mass ratio).

[Cover layer of aspect (1)]
The cover layer of the preferred embodiment (1) is bonded to the above-described write-once recording layer or a barrier layer described later via an adhesive or an adhesive material. The cover layer used in the present invention is not particularly limited as long as it is a transparent material film; however, an acrylic resin such as polycarbonate and polymethyl methacrylate; a vinyl chloride resin such as polyvinyl chloride and a vinyl chloride copolymer; It is preferable to use epoxy resin; amorphous polyolefin; polyester; cellulose triacetate and the like. Among them, it is more preferable to use polycarbonate or cellulose triacetate.
Note that “transparent” means that the transmittance is 80% or more with respect to light used for recording and reproduction.

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

  The thickness of the cover layer is appropriately defined by the wavelength and NA of the laser light irradiated for recording and reproduction. In the present invention, the thickness is in the range of 0.01 to 0.5 mm, and 0 More preferably, it is in the range of 0.05 to 0.12 mm. The total thickness of the cover layer and the layer made of an adhesive or a pressure-sensitive adhesive is preferably 0.09 to 0.11 mm, and more preferably 0.095 to 0.105 mm. The light incident surface of the cover layer may be provided with a protective layer (hard coat layer) for preventing the light incident surface from being damaged when the optical information recording medium is manufactured.

  For example, a UV curable resin, an EB curable resin, a thermosetting resin, or the like is preferably used as the adhesive used to bond the cover layer, and it is particularly preferable to use a UV curable resin. When a UV curable resin is used as an adhesive, the UV curable resin may be used as it is or dissolved in an appropriate solvent such as methyl ethyl ketone or ethyl acetate to prepare a coating solution, which may be supplied from the dispenser to the barrier layer surface. . Further, in order to prevent warpage of the produced optical information recording medium, it is preferable that the UV curable resin constituting the adhesive layer has a small curing shrinkage rate. Examples of such UV curable resins include UV curable resins such as “SD-640” manufactured by Dainippon Ink and Chemicals, Inc.

  The adhesive is applied, for example, on a surface to be bonded composed of a barrier layer, and after a cover layer is placed thereon, the adhesive is applied by spin coating to the surface to be bonded and the cover layer. It is preferable that the film is cured after being spread so as to be uniform. The thickness of the adhesive layer made of such an adhesive is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 50 μm, and still more preferably in the range of 10 to 30 μm.

  As the pressure-sensitive adhesive used for laminating the cover layer, acrylic, rubber-based, and silicon-based pressure-sensitive adhesives can be used. From the viewpoint of transparency and durability, acrylic pressure-sensitive adhesive is used. preferable. As such an acrylic pressure-sensitive adhesive, 2-ethylhexyl acrylate, n-butyl acrylate and the like are the main components, and in order to improve cohesion, short-chain alkyl acrylates and methacrylates such as methyl acrylate, ethyl acrylate, and methyl methacrylate are used. And acrylic acid, methacrylic acid, acrylamide derivatives, maleic acid, hydroxylethyl acrylate, glycidyl acrylate, and the like, which can be crosslinking points with the crosslinking agent, are preferably used. The glass transition temperature (Tg) and the crosslinking density can be changed by appropriately adjusting the mixing ratio and type of the main component, the short chain component, and the component for adding a crosslinking point.

  As a crosslinking agent used together with the said adhesive, an isocyanate type crosslinking agent is mentioned, for example. Such isocyanate-based crosslinking agents include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, naphthylene-1,5-diisocyanate, o-toluidine isocyanate, isophorone diisocyanate, triphenylmethane triisocyanate, and the like. Isocyanates, products of these isocyanates with polyalcohols, and polyisocyanates formed by condensation of isocyanates can be used. Commercially available products of these isocyanates include Coronate L, Coronate HL, Coronate 2030, Coronate 2031, Millionate MR, Millionate HTL manufactured by Nippon Polyurethane; Takenate D-102 and Takenate D-110N manufactured by Takeda Pharmaceutical Co., Ltd. , Takenate D-200, Takenate D-202; Death Module L, Death Module IL, Death Module N, Death Module HL;

  The pressure-sensitive adhesive may be uniformly applied on the surface to be bonded made of the barrier layer, and may be cured after placing the cover layer thereon, or in advance on one side of the cover layer, A predetermined amount may be uniformly applied to form a pressure-sensitive adhesive coating film, the coating film may be bonded to the surface to be bonded, and then cured. Moreover, you may use the commercially available adhesive film in which the adhesive layer was previously provided for the cover layer. The thickness of the pressure-sensitive adhesive layer made of such a pressure-sensitive adhesive is preferably in the range of 0.1 to 100 μm, more preferably in the range of 0.5 to 50 μm, and still more preferably in the range of 10 to 30 μm.

[Other layers in aspect (1)]
The optical information recording medium of the preferred embodiment (1) may have other optional layers in addition to the above essential layers as long as the effects of the present invention are not impaired. As such other optional layers, for example, a label layer having a desired image formed on the back surface of the substrate (the back surface with respect to the write-once recording layer forming surface), or between the substrate and the write-once recording layer is provided. And a barrier layer (described later) provided between the write-once recording layer and the cover layer, an interface layer provided between the light reflective layer and the write-once recording layer, and the like. Here, the label layer is formed using an ultraviolet curable resin, a thermosetting resin, a heat drying resin, or the like. These essential and optional layers may be a single layer or may have a multilayer structure.

[Light Reflecting Layer in Mode (1)]
In the optical information recording medium of the preferred mode (1), a light reflecting layer is formed between the substrate and the write-once recording layer in order to increase the reflectivity for laser light and to give the function of improving the recording / reproducing characteristics. It is preferable to do. The light reflecting layer can be formed on the substrate by vacuum-depositing, sputtering, or ion plating a light-reflecting material having a high reflectance with respect to laser light. The thickness of the light reflecting layer is generally in the range of 10 to 300 nm, and preferably in the range of 50 to 200 nm. The reflectance is preferably 70% or more.

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

[Formation process of barrier layer (intermediate layer) in aspect (1)]
In the optical information recording medium of the preferred mode (1), it is preferable to form a barrier layer between the write-once recording layer and the cover layer. The barrier layer is provided for improving the storage stability of the write-once recording layer, improving the adhesion between the write-once recording layer and the cover layer, adjusting the reflectance, adjusting the thermal conductivity, and the like. The material used for the barrier layer is not particularly limited as long as it is a material that transmits light used for recording and reproduction, and can express the above functions. Is a material with low gas and moisture permeability and is preferably a dielectric. Specifically, a material made of nitride, oxide, carbide, or sulfide such as Zn, Si, Ti, Te, Sn, Mo, or Ge is preferable. ZnS, MoO ₂ , GeO ₂ , TeO, SiO ₂ , TiO ₂ , ZuO, ZnS—SiO ₂ , SnO ₂ and ZnO—Ga ₂ O ₃ are preferable, and ZnS—SiO ₂ , SnO ₂ and ZnO—Ga ₂ O ₃ are more preferable.

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

  Next, an optical information recording medium having a preferable mode (2) will be described. Here, the optical information recording medium of the mode (2) is an optical information recording medium having a laminated type layer structure, and a typical layer structure is as follows.

(1) The first layer configuration is a configuration in which a write-once recording layer, a light reflection layer, and an adhesive layer are sequentially formed on a substrate, and a protective substrate is provided on the adhesive layer.
(2) The second layer configuration is a configuration in which a write-once recording layer, a light reflection layer, a protective layer, and an adhesive layer are sequentially formed on a substrate, and a protective substrate is provided on the adhesive layer.
(3) The third layer configuration is a configuration in which a write-once recording layer, a light reflection layer, a protective layer, an adhesive layer, and a protective layer are sequentially formed on a substrate, and a protective substrate is provided on the protective layer.
(4) In the fourth layer configuration, a write-once recording layer, a light reflecting layer, a protective layer, an adhesive layer, a protective layer, and a light reflecting layer are sequentially formed on a substrate, and a protective substrate is provided on the light reflecting layer. It is a configuration.
(5) The fifth layer configuration is a configuration in which a write-once recording layer, a light reflecting layer, an adhesive layer, and a light reflecting layer are sequentially formed on a substrate, and a protective substrate is provided on the light reflecting layer.

  Note that the layer configurations (1) to (5) are merely examples, and the layer configuration is not limited to the order described above, and a part of the layer configuration may be replaced or a part of the layer configuration may be omitted. The write-once recording layer may also be formed on the protective substrate side. In this case, an optical information recording medium capable of recording and reproducing from both sides is obtained. Furthermore, each layer may be composed of one layer or a plurality of layers. As an example of the optical information recording medium of the present invention, a recording medium having a write-once recording layer, a light reflecting layer, an adhesive layer, and a protective substrate in this order will be described below.

[Substrate (2)]
In the preferred embodiment (2), a pregroove (guide groove) having a shape in which all of the track pitch, groove width (half width), groove depth, and wobble amplitude are in the following ranges is formed. It is essential. This pre-groove is provided to achieve a higher recording density than CD-R and DVD-R. For example, the optical information recording medium of the present invention is used as a medium corresponding to a blue-violet laser. It is suitable for use.

  The track pitch of the pregroove is in the range of 200 to 600 nm, and the upper limit value is preferably 500 nm or less, more preferably 450 nm or less, and further preferably 430 nm or less. The lower limit is preferably 300 nm or more, more preferably 330 nm or more, and still more preferably 370 nm or more. If the track pitch is less than 200 nm, it is difficult to form the pregroove accurately, and a crosstalk problem may occur. If the track pitch exceeds 600 nm, the recording density may decrease.

  The groove width (half width) of the pregroove is in the range of 50 to 300 nm, the upper limit is preferably 250 nm or less, more preferably 200 nm or less, and further preferably 180 nm or less. Further, the lower limit value is preferably 100 nm or more, more preferably 120 nm or more, and further preferably 140 nm or more. If the groove width of the pregroove is less than 50 nm, the groove may not be sufficiently transferred at the time of molding or the recording error rate may be high. If it exceeds 300 nm, the pits formed at the time of recording spread. It may cause crosstalk or a sufficient degree of modulation may not be obtained.

  The groove depth of the pregroove is in the range of 30 to 200 nm, and the upper limit value is preferably 170 nm or less, more preferably 140 nm or less, and further preferably 120 nm or less. The lower limit is preferably 40 nm or more, more preferably 50 nm or more, and further preferably 60 nm or more. When the groove depth of the pregroove is less than 30 nm, a sufficient recording modulation degree may not be obtained, and when it exceeds 200 nm, the reflectivity may be significantly lowered.

  As the substrate used in the preferable mode (2), various materials used as the substrate material of the conventional optical information recording medium can be arbitrarily selected and used. Specific examples and preferable examples are described in the mode (1). ). Further, the thickness of the substrate needs to be in the range of 0.1 to 1.0 mm, preferably in the range of 0.2 to 0.8 mm, and in the range of 0.3 to 0.7 mm. It is more preferable.

  In addition, it is preferable to form an undercoat layer on the substrate surface on the side on which the write-once recording layer described later is provided for the purpose of improving flatness and adhesion, and the material of the undercoat layer and the coating method Specific examples and preferred examples of the layer thickness are the same as those of the undercoat layer of the aspect (1).

[Write-once recording layer of aspect (2)]
The detailed description of the write-once recording layer of the preferred mode (2) is the same as that of the write-once recording layer of the mode (1).

[Light reflecting layer of mode (2)]
In a preferred mode (2), a light reflecting layer may be formed on the write-once recording layer in order to increase the reflectance with respect to the laser beam or to provide a function for improving the recording / reproducing characteristics. Details regarding the light reflecting layer of the aspect (2) are the same as those of the light reflecting layer of the aspect (1).

[Adhesive layer of aspect (2)]
The adhesive layer in the preferred embodiment (2) is an arbitrary layer formed in order to improve the adhesion between the light reflecting layer and the protective substrate. As a material constituting the adhesive layer, a photo-curing resin is preferable, and in particular, a material having a small curing shrinkage rate is preferable in order to prevent the disk from warping. Examples of such a photocurable resin include UV curable resins (UV curable adhesives) such as “SD-640” and “SD-347” manufactured by Dainippon Ink, Inc. Further, the thickness of the adhesive layer is preferably in the range of 1 to 1000 μm in order to give elasticity.

[Protective board of mode (2)]
The protective substrate (dummy substrate) in the preferred mode (2) can be made of the same material and the same shape as the above-described substrate. The thickness of the protective substrate requires a thickness in the range of 0.1 to 1.0 mm, preferably in the range of 0.2 to 0.8 mm, and in the range of 0.3 to 0.7 mm. It is more preferable that

[Protective layer of aspect (2)]
In the optical information recording medium of the preferred mode (2), a protective layer may be provided for the purpose of physically and chemically protecting the light reflecting layer and the write-once recording layer depending on the layer structure. Examples of materials used for the protective layer include inorganic substances such as ZnS, ZnS—SiO ₂ , SiO, SiO ₂ , MgF ₂ , SnO ₂ , and Si ₃ N ₄ , thermoplastic resins, thermosetting resins, and UV curable materials. Organic substances such as resins can be mentioned. The protective layer can be formed, for example, by bonding a film obtained by plastic extrusion onto the light reflecting layer via an adhesive. Moreover, you may provide by methods, such as vacuum evaporation, sputtering, and application | coating.

  Further, when a thermoplastic resin or a thermosetting resin is used as the protective layer, it is also formed by dissolving these in an appropriate solvent to prepare a coating solution, and then applying and drying the coating solution. be able to. 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 a suitable solvent, and then applying the coating solution and curing it by irradiation with UV light. In these coating liquids, various additives such as an antistatic agent, an antioxidant, and a UV absorber may be added according to the purpose. The thickness of the protective layer is generally in the range of 0.1 μm to 1 mm.

[Other layers of aspect (2)]
The optical information recording medium of the preferred embodiment (2) may have other arbitrary layers in addition to the above-mentioned layers as long as the effects of the present invention are not impaired. The detailed description of the other optional layers is the same as that of the other layers in the aspect (1).

[2] Optical information recording method:
The optical information recording method of the present invention is carried out, for example, as follows using the optical information recording medium of the preferred mode (1) or (2). First, while rotating the optical information recording medium at a constant linear velocity (0.5 to 10 m / sec) or a constant angular velocity, the semiconductor laser from the cover layer side in the case (1) and from the substrate side in the case (2). Irradiate light for recording such as light. By this light irradiation, the recording layer absorbs the light and the temperature rises locally, causing a physical or chemical change (for example, generation of pits) and changing its optical characteristics, thereby recording information. It is thought that it is done.

  In the present invention, semiconductor laser light having an oscillation wavelength in the range of 390 to 440 nm (preferably 400 to 410 nm) is used as recording light. As a preferred light source, a blue-violet semiconductor laser beam having an oscillation wavelength in the range of 390 to 415 nm, and a blue-violet SHG having a central oscillation wavelength of 425 nm obtained by halving an infrared semiconductor laser beam having a central oscillation wavelength of 850 nm using an optical waveguide device. A laser beam can be mentioned. In particular, it is preferable to use a blue-violet semiconductor laser beam having an oscillation wavelength in the range of 390 to 415 nm in terms of recording density. The information recorded as described above is reproduced by rotating the optical information recording medium at the same constant linear velocity as described above, while the semiconductor laser beam is rotated in the cover layer side in the case (1), and in the case (2). Irradiation from the substrate side can be performed by detecting the reflected light.

  Hereinafter, synthesis examples of the compounds according to the examples are shown. Other compounds (S-2 to S-4, S-6 to S-22, S-24 to S-27) can be synthesized by similar methods.

[Synthesis Example 1]
Synthesis of the aforementioned compound (S-1): The compound was synthesized according to the following scheme (A).

  2.84 g of “Compound 2” was added to 50 ml of N, N′-dimethylformamide. After cooling to 0 ° C., 8.34 ml of triethylamine was added with stirring, and then 5.86 g of “Compound 1” was added. Then, after reacting at 0 ° C. for 4 hours, 8.00 g of tetrabutylammonium bromide was added and stirred for 1 hour. The reaction solution was poured into 300 ml of water and filtered to obtain white crystals. The obtained crystals were washed with ethyl acetate to obtain 6.06 g of compound (S-1).

The structure was confirmed by NMR. ¹ HNMR (DMSO-d ⁶ ): d = 0.95 (t, 24H), 1.31 (m, 16H), 1.4 to 1.9 (m, 20H), 2.05 (s, 8H) 3.15 (t, 16H), 7.89 (s, 2H)

[Synthesis Example 2]
Synthesis of the aforementioned compound (S-5): The compound was synthesized according to the following scheme (B).

  2.84 g of “Compound 2” was added to 50 ml of N, N′-dimethylformamide, and after cooling to 0 ° C., 8.34 ml of triethylamine was added with stirring, and then 6.12 g of “Compound 3” was added. Then, after reacting at 0 ° C. for 4 hours, 7.00 g of tetrabutylammonium bromide was added and stirred for 1 hour. The reaction solution was poured into 300 ml of water and filtered to obtain white crystals. The obtained crystals were washed with ethyl acetate / methanol to obtain 8.00 g of compound (S-5).

The structure was confirmed by NMR. ¹ HNMR (DMSO-d ⁶ ): d = 0.95 (t, 24H), 1.31 (m, 16H), 1.5 to 2.5 (m, 28H), 3.15 (t, 16H) , 7.92 (s, 2H)

[Synthesis Example 3]
Synthesis of the aforementioned compound S-23: The compound was synthesized according to the following schemes (C) to (D).

  0.29 g of “Compound 4” and 0.29 g of “Compound 2” were added to 5 ml of ethanol, and 0.57 ml of triethylamine was added with stirring. The mixture was reacted at room temperature for 4 hours, and the produced crystals were filtered to obtain 0.24 g of “Compound 5”.

  Add 0.24 g of “Compound 5” to 2.5 ml of dimethylformamide, add 0.27 g of “Compound 6”, react at 50 ° C. for 1 hour, cool to room temperature, add 40 ml of methanol, and filter the resulting crystals. , (S-23) 0.31 g was obtained.

  The structure was confirmed by NMR. 1H NMR (DMSO-d6): d = 2.0 (s, 8H), 3.65 (s, 6H), 7.2 to 7.8 (m, 14H), 7.9 (s, 2H), 8.15 (s, 2H), 9.0 (d, 4H), 9.7 (d, 4H), 10.75 (s, 2H).

[Synthesis of Compound (H-1) for Comparative Example]
The compound was synthesized according to the following scheme (E).

4.15 g of “Compound 3” and 2.50 g of “Compound 7” were dissolved in 40 ml of acetonitrile, and 1.28 ml of acetic anhydride was added dropwise, and then 1.90 ml of triethylamine was added dropwise and stirred and refluxed. Then, after reacting for 2 hours, 7.00 g of tetrabutylammonium bromide was added and stirred for 1 hour. The reaction solution was charged with 300 ml of ethyl acetate and filtered to obtain white crystals. The obtained crystals were washed with ethyl acetate to obtain 5.33 g of compound (H-1).

The structure was confirmed by NMR. ¹ HNMR (CDCl ₃ ): d = 0.95 (t, 12H), 1.31 (m, 16H), 1.55 to 2.7 (m, 20H), 3.22 (t, 8H), 8 .21 (s, 2H)

[Examples 1 to 4]
<Manufacture of optical information recording media>
(Production of substrate)
Thickness 1.1 mm, outer diameter 120 mm, inner diameter 15 mm, spiral pre-groove (track pitch: 320 nm, groove width: on-groove width 120 nm, groove depth: 35 nm, groove inclination angle: 65 °, wobble amplitude: 20 nm) An injection-molded substrate made of a polycarbonate resin was prepared. Mastering of the stamper used at the time of injection molding was performed using laser cutting (351 nm).

(Formation of light reflection layer)
APC light reflecting layer (Ag: 98.1 mass%, Pd: 0.9 mass) as a vacuum film-forming layer having a film thickness of 100 nm by DC sputtering in an Ar atmosphere using a Cube manufactured by Unaxis Co. %, Cu: 1.0 mass%). The film thickness of the light reflecting layer was adjusted by the sputtering time.

(Formation of write-once recording layer)
2 g of each of the compounds (S-1), (S-4), (S-5) and (S-23) in Table 1 was added to 100 ml of 2,2,3,3-tetrafluoropropanol and dissolved. A dye-containing coating solution was prepared. And the prepared pigment | dye containing coating liquid was apply | coated on the conditions of 23 degreeC and 50% RH, changing the rotation speed to 300-4000 rpm with a spin coat method on the light reflection layer. Then, it was stored at 23 ° C. and 50% RH for 1 hour to form a write-once recording layer (thickness on the groove 120 nm, thickness on the land 170 nm).

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

(Formation of barrier layer)
Then, on the write-once recording layer, using Cubes made by Unaxis, and made of ZnO—Ga ₂ O ₃ (ZnO: Ga ₂ O ₃ = 3: 7 (mass ratio)) by RF sputtering in an Ar atmosphere. A barrier layer having a thickness of 5 nm was formed.

(Covering the cover layer)
As the cover layer, a polycarbonate film (Teijin Pure Ace, thickness: 80 μm) having an inner diameter of 15 mm and an outer diameter of 120 mm and coated with an adhesive on one side, the thickness of the adhesive layer and the polycarbonate film is used. The total thickness was set to 100 μm. Then, the cover layer was placed on the barrier layer so that the barrier layer and the pressure-sensitive adhesive layer were in contact with each other, and the cover layer was pressed and pressed with a pressing member.

(Comparative Examples 1-4)
Examples were used except that the compounds (S-1), (S-4), (S-5), and (S-23) were used in place of the comparative compounds (A) to (D) represented by the following chemical formulas. Discs were created in exactly the same way as in 1-4.

  As described above, optical information recording media of Examples 1 to 4 and Comparative Examples 1 to 4 were produced.

<Evaluation of optical information recording media>
C / N (carrier-to-noise ratio) evaluation:
The produced optical information recording medium was 0.16 μm at a clock frequency of 66 MHz and a linear velocity of 5.28 m / s using a recording / reproduction evaluation machine (manufactured by Pulstec Inc .: DDU1000) loaded with a 403 nm laser and NA 0.85 pickup. The signal (2T) was recorded and reproduced, and C / N (after recording) was measured with a spectrum analyzer (manufactured by Advantest: TR4171). The results are shown in Table 3 below. In this evaluation, recording was performed on the groove. The recording power was 5.2 mW and the reproducing power was 0.3 mW.

[Examples 5 to 8]
<Manufacture of optical information recording media>
(Production of substrate)
Thickness 0.6 mm, outer diameter 120 mm, inner diameter 15 mm and spiral pregroove (track pitch: 400 nm, groove width: 170 nm, groove depth: 100 nm, groove inclination angle: 65 °, wobble amplitude: 20 nm), An injection molded substrate made of polycarbonate resin was produced. Mastering of the stamper used at the time of injection molding was performed using laser cutting (351 nm).

(Formation of write-once recording layer)
2 g of each of the compounds (S-1), (S-4), (S-5) and (S-23) shown in Table 1 is added to 100 ml of 2,2,3,3-tetrafluoropropanol and dissolved. Then, a dye-containing coating solution was prepared. And the prepared pigment | dye containing coating liquid was apply | coated on the conditions of 23 degreeC and 50% RH, changing the rotation speed to 300-4000 rpm by a spin coat method. Then, it was stored at 23 ° C. and 50% RH for 1 hour to form a write-once recording layer (thickness on groove: 170 nm, thickness on land: 120 nm).

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

(Formation of light reflection layer)
An APC light reflecting layer (Ag: 98.1% by mass, Pd: 0) as a vacuum film-forming layer having a film thickness of 100 nm was formed on the write-once recording layer using a Cube manufactured by Unaxis, and DC sputtering in an Ar atmosphere. .9 mass%, Cu: 1.0 mass%) was formed. The film thickness of the light reflecting layer was adjusted by the sputtering time.

(Lamination of protective substrate)
On the light reflection layer, an ultraviolet curable resin (SD640, manufactured by Dainippon Ink) is applied by spin coating, and a protective substrate made of polycarbonate (same as the above substrate except that no pregroove is formed) is bonded. And cured by irradiating with ultraviolet rays. The thickness of the adhesive layer made of the ultraviolet curable resin in the produced optical information recording medium was 25 μm.
(Comparative Examples 5 to 8)
Examples were used except that the compounds (S-1), (S-4), (S-5), and (S-23) were used instead of the comparative compounds (A) to (D) represented by the above chemical formulas. Disks were produced in exactly the same way as in 5-8.

  As described above, optical information recording media of Examples 5 to 8 and Comparative Examples 5 to 8 were produced.

<Evaluation of optical information recording media>
C / N (carrier-to-noise ratio) evaluation:
The produced optical information recording medium was recorded at a clock frequency of 64.8 MHz and a linear velocity of 6.61 m / s using a recording / reproduction evaluation machine (manufactured by Pulstec Corp .: DDU1000) loaded with a laser with a wavelength of 405 nm and an NA 0.65 pickup. , 0.204 μm signal (2T) was recorded and reproduced, and C / N (after recording) was measured with a spectrum analyzer (manufactured by Advantest: TR4171). The results are shown in Table 3 below. This evaluation was performed using the optical information recording method of the present invention, and recording was performed on a groove. The recording power was 12 mW and the reproducing power was 0.5 mW. The results are shown in Table 3. Here, when the C / N (after recording) is 25 dB or more, the reproduction signal intensity is sufficient and the recording characteristics are preferable.

  From the results in Table 3 above, the light provided with a recording layer containing a dye having two or more dye residues independently in the molecule, and these dye residues bonded together without a conjugated bond. The information recording media (Examples 1 to 8) had higher reproduction signal strength than the optical information recording media of Comparative Examples 1 to 8. In the same manner as in Example 5, each of the compounds (S-28), (S-29), (S-30), and (S-31) was used to record the optical information recording media (I) to (IV). ) Was produced. Even with these optical information recording media, high reproduction signal intensity was obtained.

<Effect of light preservability>
[Production of glass substrate]
20 mg of each of compounds (S-1) and (S-5) of Table 1 and comparative compounds (H-1) and (H-2) was added to 1 ml of 2,2,3,3-tetrafluoropropanol. And dissolved to prepare a pigment-containing coating solution. And the prepared pigment | dye containing coating liquid was apply | coated on the conditions of 23 degreeC and 50% RH, changing the rotation speed to 300-4000 rpm by a spin coat method on the glass substrate. Compound (H-2) is compound (I-8) described in JP-A-2001-52293, and was synthesized according to the examples described in the publication.

[Evaluation of light fastness]
Then, after storing for 1 day under light shielding at room temperature, the glass substrate was filtered on a xenon lamp (XL-500D-O 500W manufactured by USHIO DISCHARGE LAMPS) using a merry-go-round light resistance tester (customized by Eagle Engineering Co., Ltd.) (HOYA). HA-A-50) manufactured by the company was mounted, and a glass substrate coated with a pigment was placed at a distance of 8 cm from the light source and irradiated with light. Thereafter, the absorbance was measured with SHIMADZU UV-1600.

  The absorbances of the compounds (S-1) and (S-5) and the comparative compounds (H-1) and (H-2) were compared. Table 4 below shows changes in absorbance with time according to the above measurement.

  From Table 4 above, it can be seen that the compounds (S-1) and (S-5) have higher photopreservability than the comparative compounds (H-1) and (H-2).

  At the end of 48 hours, with the compound (H-2) as a reference, the remaining dye compound has the ratio shown in Table 5, and (H-1) is compared with (S-1) or (S-5) by 3 times. As described above, the present inventors have found that the dye has excellent light storage stability. This shows the usefulness of the present invention.

  From the above, by using a dye that has two or more dye residues independently in the molecule and these dye residues are bonded without a conjugated bond, good recording characteristics are exhibited and storage is achieved. It was confirmed that an optical information recording medium having good properties can be obtained. In particular, since the above effect can be obtained by using a laser having a shorter wavelength than in the case of CD-R and DVD-R, it can be said that a higher-density information recording medium and recording / reproducing method can be provided.

Claims (10)

  An optical information recording medium having a recording layer capable of recording information by irradiation with a laser beam having a wavelength of 440 nm or less on a substrate, the recording layer having two or more dye residues independently in the molecule, An optical information recording medium comprising: a dye formed by bonding the dye residue of the dye without a conjugated bond. The optical information recording medium according to claim 1, wherein the dye has a structure represented by the following general formula (1).
General formula (1)

(In General Formula (1), Dye ¹¹ , Dye ¹² , and Dye ^2k represent dye residues, and L ¹¹ and L ^2k are divalent that do not form a π-conjugated conjugate bond between the dye residues to which they are bonded. Represents a linking group, n represents an integer of 0 or more and 10 or less, k represents an integer of 0 or more and n or less, Q represents an ion for neutralizing electric charge, and y is necessary for neutralization of electric charge. Represents a number.)   The optical information recording medium according to claim 1, wherein the dye residue is an oxonol dye residue. The dye is represented by the following general formula (2-1), the following general formula (2-2), the following general formula (2-3), the following general formula (2-4), and the following general formula (2-5). The optical information recording medium according to claim 1, wherein the optical information recording medium is represented by any one of the above.

(In the above general formulas (2-1), (2-2), (2-3), (2-4) and (2-5), R represents a substituent on the methine carbon, and m represents 0 to 1 represents an integer of 1, n represents an integer of 0 to 2m + 1, and when n is an integer of 2 or more, a plurality of Rs may be the same or different from each other, and are connected to each other to form a ring. ^may, Za ^5, Za ⁶ is a group of atoms forming an acidic ^{nucleus, L 11, Q,} definition of y is ^L 11, Q, same y in formula (1), Y is -O- Or —NR ¹ — or —CR ² R ³ —, wherein R ^{1 to} R ⁹ each independently represents a hydrogen atom or a substituent, Z represents a substituted or unsubstituted alkylene group, and x represents 1 Or 2. G represents an oxygen atom or a sulfur atom.   M in the general formula (2-1), general formula (2-2), general formula (2-3), general formula (2-4), and general formula (2-5) is 0. 5. The optical information recording medium according to claim 4, wherein The dye is represented by the following general formula (5-1), general formula (5-2), general formula (5-3), general formula (5-4), and general formula (5-5) below. The optical information recording medium according to claim 5, wherein the optical information recording medium is represented by any one of the above.

(In the general formula (5-1), the general formula (5-2), the general formula (5-3), the general formula (5-4), and the general formula (5-5), R, The definitions of Z, Y, Q, and y are the same as R, Z, Y, Q, and y in formulas (2-1) to (2-5), and R ^{1 to} R ⁹ are each independently a hydrogen atom or Represents a substituent, G represents an oxygen atom or a sulfur atom, and x is 1 or 2.)   The optical information recording medium according to claim 1, wherein a light reflection layer made of a metal is provided separately from the recording layer.   The optical information recording medium according to claim 1, wherein a protective layer is provided separately from the recording layer.   The substrate is a transparent disk-shaped substrate having a pregroove with a track pitch of 50 to 600 nm on a surface thereof, and the recording layer is provided on a surface side on which the pregroove is formed. The optical information recording medium according to any one of 1 to 8.   An information recording method for recording information by irradiating the optical information recording medium according to claim 1 with a laser beam having a wavelength of 440 nm or less.