HK1099038A - Monomethine dye compound, optical information recording medium utilizing the compound and process for producing the same - Google Patents

Description

Monomethine dye compound, optical information recording medium using the same, and method for producing the same

Technical Field

The present invention relates to a monomethyldye (monomethyldye) compound, an optical information recording medium using the compound, and a method for producing the medium, and more particularly, to a monomethyldye compound which is usable for an optical recording layer of an optical information recording medium having an optical recording layer containing at least a light absorbing substance and the like, which can be reproduced by high-density and high-speed writing with a red laser beam having a wavelength of 750 to 830nm, a short-wavelength red laser beam having a wavelength of 640 to 680nm (e.g., 650 to 665nm), and a blue laser beam having a wavelength of 350 to 500nm (e.g., 405 nm) on the short-wavelength side, which are generated by a semiconductor laser, an optical information recording medium using the compound, and a method for producing the medium.

Background

At present, optical information recording media that record and reproduce using blue laser light of around 350 to 500nm (for example, around 405 nm) on the short wavelength side have been developed. In such an optical information recording medium, an organic dye compound is used for an optical recording layer, and the shorter the wavelength of laser light, the thinner the film to be formed as an optical recording layer and the higher the refractive index.

A general structure of the optical information recording medium 1(HD, DVD recordable type) capable of recording and reproducing by using a blue laser beam will be described with reference to fig. 12. Fig. 12 is an enlarged cross-sectional view of a main portion of the disk-shaped optical information recording medium 1, and is a cross-sectional view showing a cross-sectional surface of the optical information recording medium 1 in a radial direction, that is, a schematic view showing a cross-section obtained by cutting the optical information recording medium 1 perpendicularly to a surface on which the pregroove 7 is engraved and perpendicularly to a direction of the pregroove 7.

The optical information recording medium 1 includes a light-transmissive substrate 2 as a layer through which laser light is transmitted, an optical recording layer 3 (light-absorbing layer) formed on the substrate 2, a light-reflecting layer 4 formed on the optical recording layer 3, and a protective layer 5 (bonding layer) formed on the light-reflecting layer 4. In some cases, a mark printing (dummy) substrate having a predetermined thickness is laminated on the protective layer 5, and the mark printing (dummy) substrate is formed to have a predetermined thickness in accordance with the specification.

The substrate 2 is formed with a pregroove 7 in a spiral shape. The land 8, which is a portion other than the pregroove 7, is located on the right and left sides of the pregroove 7.

As shown in the figure, when the optical information recording medium 1 is irradiated with the laser beam 9 (recording light) from the light-transmitting substrate 2 (incident layer) side, the optical recording layer 3 absorbs the energy of the laser beam 9 to generate heat (or absorb heat), and the recording pit 10 is formed by thermal decomposition of the optical recording layer 3.

The substrate 2 and the optical recording layer 3 are connected to each other through a layer 1 boundary 11.

The optical recording layer 3 and the optical reflection layer 4 are connected by a layer 2 boundary 12.

The light reflecting layer 4 and the protective layer 5 are connected by a 3 rd layer boundary 13.

The light-transmitting substrate 2 is mainly made of a material having a high transparency and a resin having an excellent impact resistance, and has a refractive index for laser light of, for example, about 1.5 to 1.7, and for example, a resin plate such as a polycarbonate plate, an acrylic plate, or an epoxy plate, or a glass plate may be used.

The optical recording layer 3 is a layer formed of a light absorbing substance (light absorbing substance) containing a dye material formed on the substrate 2, and is a layer which generates heat, absorbs heat, melts, sublimates, deforms, or denatures by irradiation with the laser light 9. The optical recording layer 3 is formed by uniformly applying an azo dye, a cyanine dye, or the like dissolved in a solvent onto the surface of the substrate 2 by a spin coating method or the like, for example.

As a material used for the optical recording layer 3, any optical recording material can be used, and an organic dye having light absorption is preferable.

The light reflecting layer 4 is a metal film having high thermal conductivity and light reflectivity, and is formed by a method such as vapor deposition or sputtering using gold, silver, copper, aluminum, or an alloy containing these.

The protective layer 5 is made of a resin having the same impact resistance as the substrate 2 and excellent in adhesion. For example, the coating layer is formed by applying an ultraviolet curable resin by a spin coating method and then irradiating the resin with ultraviolet rays to cure the resin.

The mark printing substrate 6 is made of the same material as the substrate 2, and a predetermined thickness of about 1.2mm is secured.

Fig. 13 is an enlarged cross-sectional view of a main portion of a disk-shaped optical information recording medium 20 (blue laser recordable type) of another form using a blue laser beam, the optical information recording medium 20 having a light-transmitting substrate 2 with a thickness of 1.1mm, a light reflecting layer 4 formed on the substrate 2, an optical recording layer 3 (light absorbing layer) formed on the light reflecting layer 4, a protective layer 5 formed on the optical recording layer 3, a bonding layer 21 formed on the protective layer 5, and a cover layer 22 formed on the bonding layer 21 and having a thickness of 0.1mm, similar to fig. 12.

The substrate 2 is formed with a pregroove 7 in a spiral shape. The land 8, which is a portion other than the pregroove 7, is located on the right and left sides of the pregroove 7.

In addition, when the layer boundary between the substrate 2 and the light absorbing layer 3 satisfies the low reflectance, the light reflecting layer 4 is not necessarily provided.

As shown in the figure, when the information recording medium 20 is irradiated with the laser beam 9 (recording light) from the side of the light-transmitting incident layer (cover layer 22) which is a layer transmitting the laser beam, the optical recording layer 3 generates heat (or absorbs heat) by absorbing the energy of the laser beam 9, and the recording pit 10 is formed by thermal decomposition of the optical recording layer 3.

The substrate 2 and the light reflecting layer 4 are connected to each other via a layer 1 boundary 23.

The light reflecting layer 4 and the optical recording layer 3 are connected by a layer 2 boundary 24.

The optical recording layer 3 is in contact with the protective layer 5 via a layer 3 boundary 25.

Protective layer 5 is connected to bonding layer 21 via layer 4 interface 26.

Bonding layer 21 is bonded to capping layer 22 via a 5 th layer boundary 27.

In high-speed recording of the optical information recording medium 1 or 20 configured as described above, since it is necessary to perform predetermined recording at a shorter time than in the conventional recording speed or low-speed recording, the recording energy is high, and the amount of heat generated in the optical recording layer 3 during recording or the amount of heat per unit time is increased, which causes thermal unevenness and unevenness of the recording pits 10 to easily occur. Further, the emission energy of the semiconductor laser for irradiating the laser beam 9 itself has a limit, and a highly sensitive dye material which can be suitably used for high-speed recording is demanded.

In order to increase the refractive index of the optical recording layer 3, the case of utilizing the association state of the dye molecules, particularly, the J association was investigated. The J association is a state in which dye molecules are arranged edge to edge (edge to edge), and if the J association is caused, the peak of the absorption spectrum is sharply changed while the peak is shifted to the long wavelength side.

Conventionally, as a technique for producing a J aggregate by film formation, there are an LB method, a Dip method, a spin coating method and the like.

The LB method (Langmuir-Blodgett method: a method in which a molecule having a hydrophilic group and a hydrophobic group is dissolved in an appropriate solvent and developed on a water surface, and then adsorbed on a gas-liquid interface to form a monomolecular film on the water surface, and then a substrate or the like is slowly immersed therein to form a uniform thin film) can produce a precise and uniform thin film and can obtain a thin film having excellent optical characteristics. However, since high control is required in film formation, there are drawbacks in terms of time and cost.

The Dip method (a method in which a substrate is immersed in a dye solution and then taken out and dried to form a dye film on the surface) can easily control the association. However, it is difficult to form a uniform thin film and to stably maintain the film.

A thin film can be relatively easily produced by a spin coating method (a method of spreading a dropped coating liquid by centrifugal force while rotating a substrate). However, under simple coating conditions, since molecules exist in various forms, there is a problem that it is difficult to control the association. This spin coating method is superior to other methods in terms of simplicity and ease of process, and is widely used in the process of manufacturing optical information recording media such as CD-R and DVD-R.

As a J-associate film produced by a spin coating method or a similar film production method, there is a film as follows.

Patent document 1 (Japanese patent laid-open No. 2001-199919) describes a method for forming a J-aggregate thin film of an organic dye (cyanine dye). That is, a gel solution of cyanine dye and silica was used to form a J-associate film.

In this technique, the concentration of the cyanine dye in the thin film is diluted with silica, and thus sufficient dye properties cannot be obtained as a dye thin film for an optical information recording medium, and thus the cyanine dye is not suitable for an optical information recording medium. That is, this technique is difficult to apply to an optical information recording medium.

Patent document 2 (Japanese patent laid-open No. 2000-151904) describes a method of forming a J-associate film of an organic dye (cyanine dye). That is, a high-viscosity solution of a cyanine dye and a polymer material was subjected to polishing treatment to produce a J aggregate film.

In this technique, the concentration of the cyanine dye in the thin film is diluted with a polymer material, and thus the dye thin film for an optical information recording medium cannot obtain sufficient dye properties, and thus is not suitable for an optical information recording medium. In addition, if the polycarbonate of the substrate 2 is subjected to heat (temperature 130 ℃) necessary for the polishing process, the substrate 2 is denatured. That is, this technique is difficult to apply to an optical information recording medium.

Patent document 3 (Japanese patent laid-open No. 2001-305591) describes a method for forming a J-shaped association film of an organic dye (squarylium dye, Japanese: スクァリリゥム). That is, a J-form film was formed by spin coating using a dye which readily forms a J-form film.

Patent document 3 has a disadvantage that the squarylium dye lacks solubility in an organic solvent, and it is difficult to ensure solubility in a solvent that does not corrode polycarbonate, which is a material of the substrate 2 for an optical information recording medium. That is, it is difficult to obtain a sufficient thickness of a dye thin film for an optical information recording medium. Once an appropriate substituent is chemically modified in the squarylium dye molecule in order to ensure solubility, there is a problem that it is necessary to consider solubility and associativity in design because it affects the formation of a J-associate film. That is, this technique is difficult to apply to an optical information recording medium.

In addition, in patent document 4 (japanese patent No. 3429521), an LB film is used as a material for the optical recording layer 3. That is, the substrate 2 on which the dye film containing the photochromic dye is formed is used, and the substrate 2 is a ceramic substrate radiating far infrared rays. Disclosed is an optical information recording medium characterized in that the photochromic material is a molecular association of dyes and is a spiropyran (スピロピラン) J association film. A chloroform solution prepared by mixing several kinds of cyanine dyes and a specific fatty acid at an appropriate mixing ratio is expanded and compressed on a water surface, and a monomolecular film for controlling molecular arrangement is formed on the dye film containing the photochromic dye and adsorbed on the substrate 2.

In this technique, although a substrate was prepared in which the surface of a non-fluorescent glass substrate was subjected to hydrophobic treatment with trimethylchlorosilane, and twenty layers of the monolayer controlled in molecular orientation were adsorbed on one surface thereof by a vertical immersion method, it was difficult to have a sufficient thickness as a dye thin film for an optical information recording medium in practice, and it was difficult to apply the LB method to a current optical information recording medium.

Although the J-aggregate thin film can provide a high refractive index and is useful as the optical recording layer 3 of the optical information recording media 1 and 20, a simple and easy-to-control forming method has not yet been established. The LB method and the Dip method are relatively easy to produce, but have problems that a high degree of control technique is required, or a uniform thin film cannot be stably obtained. On the other hand, spin coating can easily form a thin film, but there is a problem that it is difficult to produce a J-aggregate thin film by the spin coating.

Patent document 1 Japanese patent laid-open No. 2001-199919

Patent document 2 Japanese patent laid-open No. 2000-151904

Patent document 3 Japanese patent laid-open No. 2001-305591

Patent document 4 japanese patent No. 3429521

Disclosure of The Invention

The present invention has been made in view of the above problems, and an object thereof is to provide a monomethyl dye capable of forming a uniform thin film from a J-association of dye molecules, an optical information recording medium in which optical characteristics can be improved by forming the J-association directly without providing any other auxiliary means, and a method for producing the same.

Further, the present invention addresses the problem of providing a monomethyl dye compound capable of forming a thin film having a high refractive index and excellent optical characteristics, an optical information recording medium using the compound, and a method for producing the medium.

Further, another object of the present invention is to provide a monomethyldye compound capable of forming an optical recording layer comprising a J-form aggregate by a simple method (spin coating method), an optical information recording medium using the same, and a method for producing the same.

Further, the present invention has an object to provide a monomethyl dye compound which can be applied with a solvent to a dye material without corroding a substrate such as a carbonate, an optical information recording medium using the compound, and a method for producing the medium.

Further, the present invention has an object to provide a monomethyl dye compound which is suitable for high-speed recording and high-density recording and has high sensitivity and excellent short mark recording ability, and an optical information recording medium using the same, and a method for producing the same.

That is, the present invention has been made focusing on the fact that a uniform thin film can be easily formed by spin coating, good optical characteristics (high refractive index) can be obtained by using a dye material capable of forming a J-associate, a solvent that does not corrode a substrate can be used as the dye material using a monomethyl dye compound containing an oxocyanine dye (oxocyanine dye) having good solubility, and a dye that has a large difference in refractive index between before and after recording and that is an endothermic reaction in decomposition of the dye, and the like, and the first invention is a monomethyl dye compound represented by general formula (a) in fig. 1.

The invention of the second aspect is a monomethyl dye compound represented by the general formula (B) of FIG. 2.

The third aspect of the present invention is an optical information recording medium having an optical recording layer for recording information by a laser beam, wherein the optical recording layer has a dye film having a J-association-forming substance (which can also be described as a dye film having a monomethylic dye compound represented by general formula (a) in fig. 1, the compound forming a J-association), and the optical recording layer is formed directly on the surface of the layer transmitting the laser beam on the rear side of the transmission.

It can also be described as: an optical information recording medium having an optical recording layer for recording information by laser light, wherein the optical recording layer contains a monomethyl dye compound represented by the general formula (A) in FIG. 1.

The fourth aspect of the present invention is a method for manufacturing an optical information recording medium having an optical recording layer for recording information by laser light, wherein the optical recording layer is formed by applying a monomethyl dye compound represented by general formula (a) of pattern 1 by a spin coating method.

R in the above general formula (B)₂～R₉At least one of them may be formed of a C1 group.

The monomethyl dye compound can be used in an optical recording layer of an optical information recording medium provided with the optical recording layer for recording information by laser light.

The monomethyl dye compound can form a J-associate.

The counter ion X of the monomethyl dye compound can be an ammonium compound.

As a solvent for dissolving the monomethyl dye compound, a fluorinated alcohol such as 2, 2, 3, 3-tetrafluoro-1-propanol can be used.

Water may be blended in the solvent in which the above-mentioned monomethyl dye compound is dissolved.

The water may be incorporated into the solvent at a ratio of 5 to 50 vol%.

The above-mentioned monomethyldye compound, optical information recording medium using the same, and method for producing the same can be used for recording and reproduction by blue laser light, and can also be used for CD and DVD for recording or reproduction.

In addition, the synthesis and identification of the monomethyl dye compound can refer to the synthesis and identification methods of monomethyl cyanine.

The following synthesis methods [ formula 5 ] are known, for example, the method described in U.S. Pat. No. 2310640 (Synthesis method 1), the method described in U.S. Pat. No. 2485679 (Synthesis method 2), the method described in U.S. Pat. No. 2310640 (Synthesis method 3), and the synthesis methods described in [ formula 5 ] can be used for the synthesis of the monomethyl dye compounds of the general formulae (A) and (B) of the present invention, and the compounds can be synthesized by adjusting the substituents and side chains thereof. This composition can be identified as a monomethyl dye compound belonging to the specific compounds of the above-mentioned general formulae (A) and (B) by using an NMR analyzer, a GC/MS analyzer or the like. As a synthesis method in which the substituents and side chains are adjusted by the synthesis method 1, a synthesis method represented by the general formula shown in example 1 described later is shown.

[ solution 5 ]

(Synthesis method 1)

In the present invention, since a specific dye material such as the monomethyldye compound shown in fig. 1 is used in the monomethyldye compound, the optical information recording medium using the same, and the method for producing the same, a thin film formed by J-association of dye molecules can be formed even by a simple method such as spin coating. By sharpening the absorption spectrum of the J-associated dye film and lengthening the wavelength, a film having a high refractive index can be formed. Therefore, by the light absorption from the J association of the dye molecule, the associated dye is thermally decomposed, and a difference in refractive index before and after recording can be easily generated. Further, the thermal decomposition of the J-associated dye is an endothermic reaction, and heat release control of heat generated by an exothermic reaction is not required as in the conventional case.

That is, a recording material thin film having excellent optical properties such as a high refractive index and a refractive index difference before and after recording and thermal properties such as endothermic reaction can be uniformly formed, and the above-mentioned aggregate can be formed by a simple method such as spin coating, and an optical information recording medium having excellent properties can be obtained without modifying the conventional process.

Further, by using a single methyl dye compound having good solubility, a dye material can be coated with a solvent such as 2, 2, 3, 3-tetrafluoro-1-propanol (TFP) which does not corrode a substrate.

In particular, according to the first aspect of the present invention, the monomethyldye compound having the structure shown in FIG. 1 can form J-junctions, and at the same time, can be easily made into a thin film by a spin coating method, and can form a thin film having excellent optical characteristics as an optical recording layer of an optical information recording medium.

In particular, according to the second aspect of the present invention, the monomethyldye compound having the structure shown in FIG. 2 can form J-junctions, and at the same time, the thin film can be easily formed by spin coating, and a thin film having excellent optical characteristics as an optical recording layer of an optical information recording medium can be formed.

Particularly, according to the invention of the third aspect, a uniform J-associated body film can be formed as an optical recording layer without performing other treatment for forming J-association, or without forming other auxiliary layers or the like.

Further, if the optical recording layer is formed by spin coating using the monomethyl dye compound shown in fig. 1, the spectrum generated by J-association can be made steep, the refractive index of the optical recording layer can be increased, and high-speed and high-density recording can be performed.

Particularly, according to the invention of the fourth aspect, since the monomethyldye compound shown in FIG. 1 is used, a thin film composed of a J aggregate can be formed even by spin coating, and an optical recording layer having good optical characteristics can be formed.

Brief description of the drawings

FIG. 1 is an explanatory view showing a general formula (A) of a single-use methyl dye compound (oxocyanine dye) used in the present invention.

FIG. 2 is an explanatory view showing a general formula (B) of a single-use methyl dye compound (oxocyanine dye) used in the present invention.

Fig. 3 is an explanatory view showing an oxocyanine dye (compound I) used in example 1.

FIG. 4 is a diagram illustrating a cyanine dye (Compound II) used for comparison in example 1.

FIG. 5 is a graph showing the results of the spectroscopic measurement of each (three) compounds in example 1.

FIG. 6 is Table 1 showing the respective optical properties at 420nm of a thin film (on a single plate) of compound I, II.

FIG. 7 is a diagram illustrating Compound III (light stabilizer) used in example 2.

FIG. 8 is a table 2 showing the results of evaluation of electrical characteristics of the optical information recording media 1 obtained in example 2.

Fig. 9 is an explanatory view of an oxocyanine dye (compound IV) used in example 3.

Fig. 10 is a graph showing absorption spectra of compound IV in TFP and water.

Fig. 11 is a graph showing absorption spectra of compound IV in TFP and chloroform.

Fig. 12 is an enlarged cross-sectional view of a main portion of a general disk-shaped optical information recording medium 1.

Fig. 13 is an enlarged cross-sectional view of a main portion of a general disc-shaped optical information recording medium 20 of another embodiment.

Description of the symbols

1 optical information recording medium (FIG. 12)

2 base plate

3 optical recording layer (light absorption layer)

4 light reflecting layer

5 protective layer (bonding layer)

6-mark printed board

7 pregroove

8 lamp

9 laser (recording light, regeneration light)

10 recording pit

11 layer 1 boundary

12 layer 2 boundary

13 layer 3 boundary

14 4 th layer boundary

20 optical information recording medium (FIG. 13)

21 bonding layer

22 cover layer

23 layer 1 boundary

24 layer 2 boundary

25 layer 3 boundary

26 layer 4 boundary

27 5 th layer boundary

Best Mode for Carrying Out The Invention

Since the thin film formed of the J-shaped associative substance is formed using the monomethyl dye compound shown in FIG. 1, an optical information recording medium having a uniform optical recording layer with a high refractive index can be realized by a simple spin coating method.

Fig. 1 is an explanatory view showing a general formula (a) of a monomethyl dye compound (oxocyanine dye) used in the present invention, from which an optical recording layer 3 of optical information recording media 1, 20 is formed.

The monomethyl dye compound has an oxocyanine (monomethyl oxocyanine) as a dye skeleton. The oxocyanine may have S, Se as the O atom of the heteroatom of-O-in the rings on both sides of the dye skeleton, and the heteroatom of one ring and the heteroatom of the other ring may be selected from O, S and Se, and may be the same or different. In the general formula (a), O as a heteroatom in one ring is Y1, O as a heteroatom in the other ring is Y2, and Y1 and Y2 may be either O, S or Se, and may be the same or different.

In the general formula (A), X represents an ion required for neutralizing an intramolecular charge, and X may be selected from H⁺、Na⁺、K⁺And ammonium compounds (tertiary amine compounds, quaternary ammonium compounds).

n1 and n2 each represent the size of an alkyl chain (number of carbon atoms), and each represents an integer of 1 to 20, and may be the same or different.

Z1 and Z2 may be the same or different and each represent an atomic group necessary for forming a five-or six-membered aromatic ring and a nitrogen-containing heterocyclic ring (forming a cyclic group of any of the five-membered aromatic ring, the six-membered aromatic ring, the five-membered nitrogen-containing heterocyclic ring and the six-membered nitrogen-containing heterocyclic ring), and Z1 and Z2 may have a substituent.

R represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or a heterocyclic group.

R10 and R11 each represent any of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. In particular, R10 is preferably ethyl or propyl. R11 is preferably a lower alkyl group such as ethyl group or propyl group. At least one of R2 to R9 is preferably a C1 group. Other halogen groups may be used.

Examples of the aromatic ring include a substituted or unsubstituted benzene ring or naphthalene ring, Z1 represents any of 4 of the following general formula [ formula 6 ], Z2 represents any of 4 of the following general formula [ formula 7 ], and Z1 and Z2 may be the same or different (wherein D1 and D2 each represents a hydrogen atom, an alkyl group, an alkoxy group, a hydroxyl group, a halogen atom, a carboxyl group, an alkoxycarbonyl group, an alkylcarboxyl group, an alkylhydroxyl group, an aralkyl group, an alkenyl group, an alkylamide group, an alkylamino group, an alkylsulfonyl group, an alkylcarbamoyl group, a sulfamoyl group, an alkylsulfonyl group, a phenyl group, a cyano group, an ester group, a nitro group, an acyl group, an allyl group, an aryl group, an aryloxy group, an alkylthio group, an arylthio group, a phenylazo group, a pyridazoyl group, an alkylcarbonylamino group, a sulfonamide group, an amino group, an alkylsulfonic group, a thiocyano group, a mercapto group, the substituents for the alkylaminosulfo group, the vinyl group and the sulfo group may be the same or different, and p and q are the number of the substituents and each represents 1 or an integer larger than 1. )

[ claim 6 ]

As described in examples below, when X is combined with an ammonium compound as a counter ion, the dye has good solubility without containing moisture in the solvent, whereas when X is H⁺、Na⁺、K⁺In the case of the combination, it is preferable to use water in a mixing ratio of 5 to 50 vol% for dissolving the dye, and such a case is sometimes required.

In the present invention, the optical recording layer 3 of the optical information recording media 1 and 20 can be formed by the monomethyl dye compound (oxocyanine dye) of the general formula (B) shown in fig. 2, as in fig. 1.

In the general formula (B), X represents an ion necessary for neutralizing an intramolecular charge, and X may be selected from H, as in the general formula (A)⁺、Na⁺、K⁺And an ammonium compound.

n1 and n2 each represent the size of an alkyl chain (number of carbon atoms), and each represents an integer of 1 to 20, and may be the same or different.

R1, R2, R3, R4, R5, R6, R7, R8 and R9 each represents a hydrogen atom, a halogen atom, an aliphatic group, an aryl group or a heterocyclic ring. R10 and R11 each represent a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group (these are lower alkyl groups), or a hexyl group.

In the general formulae (a) and (B), many of R, R1 to R9 may be substituted with a substituent, and examples of the various substituents include aliphatic hydrocarbon groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, and tert-pentyl group; ether groups such as methoxy, trifluoromethoxy, ethoxy, propoxy, isopropoxy, butoxy, tert-butoxy, pentyloxy, phenoxy, and benzyloxy; ester groups such as methoxycarbonyl, trifluoromethoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, acetoxy, trifluoroacetyloxy, benzoyloxy and the like; alkylsulfonyl such as methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, butylsulfonyl, tert-butylsulfonyl and pentylsulfonyl; a methylsulfamoyl group; alkylsulfamoyl groups such as dimethylsulfamoyl, ethylsulfamoyl, diethylsulfamoyl, propylsulfamoyl, dipropylsulfamoyl, butylsulfamoyl, dibutylsulfamoyl, pentylsulfamoyl and dipentylsulfamoyl; examples of the halogen group include a fluorine group, a chlorine group, a bromine group and an iodine group, and may include a nitro group and a cyano group.

The aromatic ring may be a monocyclic benzene ring, and the heterocyclic ring preferably contains 1 or more hetero atoms selected from a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom.

The aromatic ring or heterocyclic ring may have 1 or more aliphatic hydrocarbon groups selected from, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 2-methylpentyl, hexyl, isohexyl, 5-methylhexyl; alicyclic hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cyclohexenyl; aromatic hydrocarbon groups such as phenyl, biphenyl, o-tolyl, m-tolyl, p-tolyl, o-cumyl, m-cumyl, p-cumyl, xylyl, mesityl, styryl, cinnamoyl, and naphthyl; an aliphatic, alicyclic or aromatic amino group which may be substituted or unsubstituted, such as an ester group such as a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an acetoxy group or a benzoyloxy group, a primary amino group, a methylamino group, a dimethylamino group, an ethylamino group, a diethylamino group, a propylamino group, a dipropylamino group, an isopropylamino group, a diisopropylamino group, a butylamino group or a dibutylamino group; alkylsulfamoyl groups such as methylsulfamoyl, dimethylsulfamoyl, ethylsulfamoyl, diethylsulfamoyl, propylsulfamoyl, dipropylsulfamoyl, isopropylsulfamoyl, diisopropylsulfamoyl, butylsulfamoyl and dibutylsulfamoyl, and substituents such as carbamoyl, carboxyl, cyano, nitro, hydroxyl, sulfo, sulfamino and sulfamoyl.

In addition, in the oxocyanine dyes (monomethyl dye compounds) represented by the general formulae (a) and (B), if a cis/trans isomer exists in the structure, both isomers are included in the present invention.

Further, by selecting the oxocyanine dye having the structure shown in fig. 1 and 2 and a solvent, a thin film containing a J-associate can be easily produced by spin coating.

Further, by adding water to the solvent used in the spin coating method, that is, the polar solvent which does not corrode the substrate (5 to 50% by volume, if the lower limit is not satisfied, the solubility is insufficient, and if the upper limit is exceeded, the metal material of the reflective layer is adversely affected), the solubility of the dye can be improved, and the J-group forming ability can be improved.

The solvent is preferably a fluorinated alcohol such as 2, 2, 3, 3-tetrafluoro-1-propanol, and cellosolves such as chloroform, dichloroethane, methyl ethyl ketone, dimethylformamide, methanol, toluene, cyclohexanone, acetylacetone, diacetone alcohol, and ethylene glycol monomethyl ether may be used as long as the substrate is not corroded; dioxane and the like may be used alone or in combination, and one fluorinated alcohol may be used alone or a plurality of fluorinated alcohols may be used in combination.

By using such a dye material for forming J-junction, it is possible to increase the refractive index of the optical recording layer 3, and to easily reduce the film thickness of the optical recording layer 3, and it is possible to manufacture the optical information recording media 1 and 20 having excellent recording characteristics in the wavelength range of about 350 to 500nm while securing a high modulation degree. That is, by breaking the J-association at the time of recording, the difference in refractive index between before and after recording can be secured, and the recording sensitivity can be improved.

In addition, while thermal decomposition of a general dye is an exothermic reaction, thermal decomposition in the J association state of the oxocyanine dye used in the present invention is an endothermic reaction, and therefore thermal diffusion at the time of decomposition can be suppressed.

Examples

The dye material for optical information recording medium, the optical information recording medium using the same, and the method for manufacturing the same according to the embodiments of the present invention will be described below with reference to fig. 3 to 11. In fig. 12 and 13, the same portions are denoted by the same reference numerals, and detailed description thereof is omitted.

Example 1

The synthesis method using the general formula for adjusting the substituents and side chains by the synthesis method 1 shown in [ formula 5 ] is shown in [ formula 8 ] below. Wherein Z1, Z2, and n (n1 ═ n2 ═ n) are as defined above for general formula (a), and R represents a hydrogen atom or a substituent.

Specifically, an oxocyanine dye compound (monomethyl dye compound) shown in fig. 3 can be synthesized by the synthesis method described below [ formula 9 ], and the product thereof is confirmed by an NMR analyzer.

[ claim 8 ]

[ claim 9 ]

Example 2

1.5g of the oxocyanine dye (compound I) shown in FIG. 3 was weighed out and dissolved in 100mL of 2, 2, 3, 3-tetrafluoro-1-propanol (TFP) to prepare a solution of 15 g/L.

0.25mL of the solution was measured, and the solution was dropped into a 1000mL volumetric flask, 2, 3, 3-tetrafluoro-1-propanol was added thereto to obtain a constant volume of 1000mL, and after the solution was sufficiently stirred, spectroscopic measurement was performed.

1mL of the prepared solution was dropped on a single glass plate having a thickness of 0.6mm and a square width of 4cm, and then spin-coated at a rotation speed of 300rpm for 30 seconds to obtain a uniform J-aggregate thin film.

For comparison, the cyanine dye (compound II, fig. 4) was spin-coated on the single plate as in compound I above.

The single plate having a thin film of these compounds I, II was subjected to measurement of spectroscopic spectrum.

Fig. 5 is a graph showing the results of the above-described spectroscopic measurement of each (three) compounds, and if the absorption spectrum of compound I in a solution is compared with the absorption spectrum on a single plate, the spectral shape of the single plate is compared with the state of the solution, and it is seen that the J-association is characterized by a longer wavelength and a sharper sharpness. Even when the film was made thin, the absorption spectrum of the thin film of compound I was found to be sharp as compared with compound II in which the dye molecules showing no J-association were in a relatively dispersed state.

Thus, it was confirmed that the dye film formed with the J-aggregates was formed by observing the change in the absorption spectrum between the solution state and the thin film state of the compound.

For example, the peak width at half maximum can be confirmed by shifting the absorption peak in a thin film state to a longer wavelength side than the absorption peak in a solution state, and by making the half width of the absorption spectrum in a thin film state narrower than the half width of the absorption spectrum in a solution state.

However, the method is not limited to this method, and the method may be confirmed by comparing the absorption spectrum of the monomer in the solution with the absorption spectrum in a state of being thinned as described above, and various confirmation methods may be employed.

FIG. 6 is Table 1 showing the optical properties of a thin film (on a single plate) of Compound I, II at a wavelength of 420nm, and it was confirmed that the film had good optical properties in which the refractive index n was improved by the formation of a J-aggregate.

In addition, for compound I, II, the fluorescence lifetime was measured. The fluorescence lifetime of compound I having J-associates was 29ps, that of compound II having no J-associates was 4ps, and that of a general J-associate film was 51ps (j.phys.chem., 2000, 104, 9630(n.kometani, h.nakajima, k.asami, y.yonezawa, o.kajimoto)), so that compound I had a longer fluorescence lifetime than compound II, which was about 50% of that of a general J-associate film.

In addition, phosphorescence was also measured. None was observed in compound I, and compound II.

As described above, it was found that a uniform J-associated material film can be more easily formed by forming no J-associated material in the cyanine dye film of the compound II and forming a J-associated material in the oxocyanine dye film of the compound I and applying the J-associated material by spin coating.

Example 3

An example in which the compound I (J-associative oxocyanine dye thin film, fig. 3) used in example 1 was used in the optical recording layer 3 of the optical information recording medium 1 is described below.

1.5g of oxocyanine dye (compound I) was weighed out and dissolved in 100mL of 2, 2, 3, 3-tetrafluoro-1-propanol to prepare a solution of 15 g/L. The compound III shown in figure 7 was added as a light stabilizer at a weight ratio of 30%. Other aminium-based or preferably terminal onium (ジィモァニゥム, diimmonium) stabilizers may also be used.

A uniform J aggregate thin film was obtained by applying 1mL of the coating solution to a polycarbonate disc-shaped substrate 2 having 120mm outer diameter and 0.6mm thickness pre-grooves 7 engraved at 0.40 μm intervals by spin coating at a predetermined number of revolutions.

The transparent substrate 2 coated with the dye was subjected to a heat treatment at 80 ℃ for 30 minutes, and the remaining solvent and water were volatilized to form a dye surface (optical recording layer 3).

Silver (Ag) was sputtered onto the upper surface of the optical recording layer 3 to form a light reflecting layer 4 having a thickness of 100 nm.

The dye splashed to the peripheral and inner peripheral portions of the substrate 2 was washed with methanol and washed away.

An ultraviolet-curable resin binder SD-318 (manufactured by japan ink chemical industry) was spin-coated on the upper surface of the light reflective layer 4, and then irradiated with ultraviolet rays to be cured, thereby forming a protective layer 5.

An ultraviolet-curable resin adhesive was applied to the surface of the protective layer 5, and a mark-printing substrate 6 of the same material and shape (thickness 0.6mm, outer diameter 120mm) as described above was laminated, and the adhesive was irradiated with ultraviolet light and cured to bond the layers, thereby producing a recordable optical information recording medium 1.

Thus, the optical information recording medium 1 having a uniform J-association complex of the oxocyanine dye in the optical recording layer 3 was obtained by the compound I.

Further, using the compound II (fig. 4) used in example 1, an optical recording layer 3 was formed in the same manner as described above, and the optical information recording medium 1 was obtained.

FIG. 8 is a table 2 showing the results of evaluation of electrical characteristics of the respective optical information recording media 1, and the optical information recording media 1 having the optical recording layer 3 formed of the compound I have a higher recording sensitivity because of a lower energy required for recording, and an improved C/N level of the shortest mark length, and the symmetry in recording of random recording information can be achieved at a lower energy.

Example 4

Hereinafter, an experiment for confirming the solution dependency of the J-association will be described.

1.5g of the oxocyanine dye (compound IV) shown in FIG. 9 was weighed out and dissolved in 50mL of a mixed solution of 2, 2, 3, 3-tetrafluoro-1-propanol (TFP) and 50mL of water to prepare a solution of 15 g/L.

0.25mL of the solution was measured and dropped into a 1000mL volumetric flask, and 2, 2, 3, 3-tetrafluoro-1-propanol was added thereto to give a constant volume of 1000 mL. The solution was sufficiently stirred and subjected to spectroscopic measurement.

The solution thus prepared was dropped onto a single plate of 4cm square glass having a thickness of 0.6mm, and then spin-coated at a rotation speed of 300rpm for 30 seconds to obtain a uniform J-aggregate thin film.

For comparison, 1.5g of the oxocyanine dye (compound IV, FIG. 9) was weighed and dissolved in 50mL of a mixture of 2, 2, 3, 3-tetrafluoro-1-propanol and 50mL of chloroform to prepare a 15g/L solution.

As in the case of the mixed solution of TFP and water described above, 0.25mL of the solution was measured and dropped into a 1000mL volumetric flask, and 2, 2, 3, 3-tetrafluoro-1-propanol was added to the flask to thereby obtain a constant volume of 1000 mL. After the solution was sufficiently stirred, spectroscopic measurement was performed.

As in the case of the mixed solution of TFP and water, 1mL of the solution prepared above was dropped on a single plate of glass having a thickness of 0.6mm and 4cm square, and then spin-coated at a rotation speed of 300rpm for 30 seconds to obtain a uniform J-shaped aggregate film.

Spectroscopic measurements were performed on these compounds IV (four, two each in solution and on a single plate).

Fig. 10 is a graph showing absorption spectra of compound IV in TFP and water, and fig. 11 is a graph showing absorption spectra of compound IV in TFP and chloroform, which are shown in solution and in a thin film, respectively.

As shown in fig. 10, in the case of compound IV, if the absorption spectrum in the solution is compared with the absorption spectrum on the single plate, it is known that J-association occurs because the shape of the absorption spectrum on the single plate is made longer and sharper compared with the solution state.

As shown in fig. 11, even in the same compound IV, when chloroform was mixed as a solvent without mixing water, the tendency of the single plate to have a long wavelength and the tendency of the single plate to have a sharp peak were not confirmed at all, and therefore, it was not considered that J-aggregates were formed.

The thin film on the single plate of compound IV was also found to have J-association by the same identification method (measurement of fluorescence lifetime and phosphorescence) as in example 1.

The mixing ratio of TFP and water is 5 to 50 vol%, and if it is less than 5%, the compound IV is insoluble in the solvent, and if it exceeds 50%, it may adversely affect the metal material of the light reflecting layer 4 located on the upper layer of the optical recording layer 4.

In addition, in the above-described embodiments, an example in which a single dye film formed of a monomethyl dye compound is used as the optical recording layer is exemplified, but not limited thereto, and as the optical recording layer, a mixture containing a monomethyl dye compound and other dyes such as cyanine dye, phthalocyanine dye, azo dye, or the like or additives may also be used.

Claims (18)

1. A monomethyl dye compound represented by the following general formula (A),

wherein Z1 and Z2 may be the same or different and each represent an atomic group necessary for forming a five-or six-membered aromatic ring and a nitrogen-containing heterocyclic ring, and Z1 and Z2 may have a substituent; r represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or a heterocyclic group; r10 and R11 each represent any of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group; n1 and n2 each represent the number of carbon atoms in an alkyl chain, and represent an integer of 1 to 20, and may be the same or different.

2. A monomethyl dye compound represented by the following general formula (B),

wherein R1 to R9 each represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or a heterocyclic group, and may be the same or different; r10 and R11 each represents a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, or a hexyl group; n1 and n2 each represent the number of carbon atoms in an alkyl chain, and each represents an integer of 1 to 20, and may be the same or different.

3. The monomethyl dye compound according to claim 2, wherein in the general formula (B), at least one of R2 to R9 is a Cl group.

4. The monomethyldye compound according to any one of claims 1 to 3, which is used for an optical recording layer of an optical information recording medium having the optical recording layer for recording information by a laser beam having a wavelength of 350 to 500 nm.

5. A monomethyl dye compound according to any one of claims 1 to 4, wherein a J-associate is formed.

6. A monomethyl dye compound according to any one of claims 1 to 5, wherein X as the counterion is an ammonium compound.

7. An optical information recording medium having an optical recording layer for recording information by a laser beam, wherein the optical recording layer has a dye film having a J-association structure, and the optical recording layer is formed directly on a surface of the layer transmitting the laser beam on a rear side thereof.

8. The optical information recording medium according to claim 7, wherein the optical recording layer is composed of a dye film containing a monomethyl dye compound forming a J-associate.

9. The optical information recording medium according to claim 8, wherein the optical recording layer contains a monomethyl dye compound represented by the following general formula (A),

wherein Z1 and Z2 may be the same or different and each represent an atomic group necessary for forming a five-or six-membered aromatic ring and a nitrogen-containing heterocyclic ring, and Z1 and Z2 may have a substituent; r represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or a heterocyclic group; r10 and R11 each represent any of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group; n1 and n2 each represent the number of carbon atoms in an alkyl chain, and represent an integer of 1 to 20, and may be the same or different.

10. The optical information recording medium according to any of claims 7 to 9, wherein the laser light has a wavelength in the range of 350 to 500 nm.

11. The optical information recording medium according to any of claims 7 to 10, wherein the optical recording layer is a dye film formed of a mixture containing a monomethyl dye compound.

12. The optical information recording medium according to any of claims 9 to 11, wherein the monomethyl dye compound contains X as a counter ion thereof.

13. A method for producing an optical information recording medium having an optical recording layer for recording information by laser light, characterized in that the optical recording layer is formed by applying a monomethyl dye compound represented by the following general formula (A) by spin coating,

wherein Z1 and Z2 may be the same or different and each represent an atomic group necessary for forming a five-or six-membered aromatic ring and a nitrogen-containing heterocyclic ring, and Z1 and Z2 may have a substituent; r represents a hydrogen atom, a halogen atom, an aliphatic group, an aromatic group or a heterocyclic group; r10 and R11 each represent any of a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group; n1 and n2 each represent the number of carbon atoms in an alkyl chain, and represent an integer of 1 to 20, and may be the same or different.

14. The method for producing an optical information recording medium according to claim 13, wherein the monomethyl dye compound forms a J-associate.

15. The method for producing an optical information recording medium according to claim 13 or 14, wherein the monomethyl dye compound contains X as a counter ion thereof, an ammonium compound.

16. The method for producing an optical information recording medium according to any of claims 13 to 15, wherein a fluorinated alcohol such as 2, 2, 3, 3-tetrafluoro-1-propanol is used as a solvent for dissolving the monomethyl dye compound.

17. The method for producing an optical information recording medium according to any of claims 13 to 16, wherein water is added to the solvent in which the monomethyl dye compound is dissolved.

18. The method for producing an optical information recording medium according to claim 17, wherein the mixing ratio of the water with respect to the solvent is 5 to 50 vol%.