JPH0940659A - Optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical recording medium capable of regenerating, etc., by a near infrared laser of 770-830nm wavelength and capable of recording and regenerating by a red laser of 620-690nm wavelength, containing a specific azo compound as a pigment. SOLUTION: This optical recording medium contains an azo compound of formula I having an absorption maximum at 450-630nm wavelength (R1 and R2 are independently H or an alkyl, etc.; R3 , R4 , R5 and R6 are independently H or a halogen, etc.; R7 , R8 and R9 are independently H or a halogen, etc.; X is S or O). The objective compound of the formula I can be obtained by diazotizing a compound of formula II, adding the reaction product to a solution of a compound of formula III and subjecting to a coupling reaction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium, and more particularly, an optical recording medium capable of reproducing or recording and reproducing with a near infrared laser having a wavelength of 770 to 830 nm and recording and reproducing with a red laser having a wavelength of 620 to 690 nm. Recording medium

[0002]

2. Description of the Related Art As an optical recording medium having a reflective layer on a substrate, a recordable or recordable CD corresponding to the compact disc (hereinafter abbreviated as CD) standard has been proposed [eg Nikkei Electronics, No. 465, p. 10
7, January 23, 1989]. As shown in FIG. 1, this optical recording medium has a recording layer 2, a reflective layer 3 and a protective layer 4 formed in this order on a substrate 1. When the recording layer of this optical recording medium is irradiated with a laser beam such as a semiconductor laser with high power, the recording layer undergoes a physical or chemical change to record information in the form of pits. The pit information can be reproduced by irradiating the formed pits with a low-power laser beam and detecting the reflected light. Generally, wavelengths of 770 to 8 are used for recording / reproducing of such an optical recording medium.
Since a near-infrared semiconductor laser of 30 nm is used and complies with CD standards such as Red Book and Orange Book, it has a feature that it is compatible with CD players and CD-ROM players.

Recently, development of semiconductor lasers having a wavelength shorter than 770 nm has progressed, and red semiconductor lasers having wavelengths of 680 nm and 630 nm have been put into practical use [eg Nikkei Electronics, No. 592, p. 65,1993
October 11, issue]. By reducing the beam spot by shortening the wavelength of the recording / reproducing laser, a high-density optical recording medium becomes possible. In addition, large-capacity optical recording media capable of storing moving images have been developed by shortening the wavelength of semiconductor lasers and data compression technology [eg, Nikkei Electronics, No. 589, p. 55, 1993 8
Month 30th issue]. Such a high-density optical recording medium can record a large amount of data such as a moving image, and the video C
It is expected to be used for applications such as D. [eg Nikkei Electronics, No. 594, p. 169, 1993 11
Month 8 issue]. Further, in Japanese Patent Laid-Open No. 278519/1990, high density recording with a short wavelength laser of 680 nm is used.
High density high speed recording has been proposed by a method of reproducing at 80 nm.

On the other hand, Japanese Patent Laid-Open No. 6-40162 discloses that
An optical recording medium capable of recording / reproducing with a short wavelength laser has been proposed. This medium uses an indocarbocyanine dye in the recording layer and can be recorded with a 630 nm semiconductor laser or a helium neon laser. A 490 nm blue / green semiconductor laser having a wavelength shorter than 630 nm has also been studied, but has not yet reached the stage of practical application [eg, Applied Physics Letter, p. 1272-
1274, Vol. 59 (1991) and Nikkei Electronics, No. 552, P.I. 90, April 27, 1992
Japanese issue]. From such a background, the recording / reproducing wavelength of the optical recording medium tends to be shortened to around 630 nm.
Therefore, it is necessary to develop an optical recording medium compatible with this, and further, a compatible optical recording medium compatible with the conventional 780 nm is also desired. However, in the conventional optical recording medium, since the organic dye used in the recording layer has large absorption at a wavelength of 620 to 690 nm and a small refractive index, the reflectance is low, and reproduction with a red laser having a wavelength of 680 nm or 630 nm is impossible. I knew it was.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to
It is possible to record and / or reproduce with a near-infrared laser of 0 nm (such as a commercially available CD player), and a wavelength of 68.
An object of the present invention is to provide an optical recording medium capable of recording and / or reproducing with a red laser of 0 or 630 nm.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention. That is, the present invention provides an optical recording medium having a recording layer, a reflective layer and a protective layer on a substrate, wherein the recording layer has the following general formula (1)
, An optical recording medium containing an azo compound having an absorption maximum at a wavelength of 450 to 630 nm, an optical recording medium containing an optical absorption compound having an absorption maximum at a wavelength of 650 to 900 nm in the recording layer, a wavelength of 650 to An optical recording medium in which the light absorbing compound having an absorption maximum at 900 nm is a phthalocyanine compound. The content of the light absorbing compound having an absorption maximum at a wavelength of 650 to 900 nm is 0.1 to 50 with respect to the azo compound.
An optical recording medium which is or is the weight percent. The reflectance measured from the substrate side with respect to the light selected from the near-infrared laser having the wavelength of 770 to 830 nm is 65% or more, and the recording and / or reproduction can be performed by the near-infrared laser having the wavelength of 770 to 830 nm, and the wavelength of 620. An optical recording medium having a reflectance of 15% or more with respect to light selected from a red laser of 690 nm to a substrate and capable of recording and / or reproducing with a red laser having a wavelength of 620 to 690 nm. .

[0007]

Embedded image [Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkenyl group, R ₃ , R ₄ , R ₅ and R ₆ are each independently a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, a sulfone group, a sulfonamide group, an amino group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted Alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted acyl group, substituted or unsubstituted alkylcarboxyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted Alkylsulfonamino group, substituted or unsubstituted alkylamino group, substituted or unsubstituted alkylsulfone group, substituted or It represents an unsubstituted alkenyl group,
R ₁ and R ₄ , R ₂ and R ₆ and R ₁ and R ₂ may form a ring through a linking group, and R ₇ , R ₈ and R ₉ are each independently a hydrogen atom, a halogen atom or a hydroxy group. Group, carboxyl group, sulfone group, sulfonamide group, amino group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted acyl group, substituted or unsubstituted Substituted alkylcarboxyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted alkylsulfonamino group, substituted or unsubstituted alkylamino group, substituted or unsubstituted alkylsulfone Group, substituted or unsubstituted alkenyl group, cyano group, nitro group, mercapto group, thiocyano group, chlorosulfone group, substituted or unsubstituted A alkenylthio group, a substituted or unsubstituted alkylazomethine group, a substituted or unsubstituted alkylaminosulfone group, and X represents a sulfur atom or an oxygen atom.] In the present invention, the wavelength 450 represented by the general formula (1) is used. ~ 63
By using an azo compound having an absorption maximum at 0 nm or a mixture of the azo compound and a light absorbing compound having an absorption maximum at 650 to 900 nm for the recording layer, 770
Provided is an optical recording medium which can be recorded and / or reproduced by a laser selected from ˜830 nm and can be recorded and / or reproduced by a red laser having a wavelength of 620 to 690 nm.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. The optical recording medium of the present invention has a recording layer and a reflective layer on a substrate. The optical recording medium refers to both a read-only optical read-only medium in which information is recorded in advance and an optical recording medium in which information can be recorded and reproduced. However, here, as a suitable example, an optical recording medium capable of recording and reproducing the latter information, particularly an optical recording medium in which a recording layer, a reflective layer and a protective layer are formed in this order on a substrate will be described. This optical recording medium has a four-layer structure as shown in FIG. That is, a recording layer 2 is formed on a substrate 1, a reflective layer 3 is provided in close contact with the recording layer 2, and a protective layer 4 further covers the reflective layer 3. As a substrate,
Basically, any material that is transparent at the wavelengths of the recording light and the reproducing light may be used. For example, polycarbonate resin, vinyl chloride resin, acrylic resin such as polymethylmethacrylate,
Polymer materials such as polystyrene resin and epoxy resin and inorganic materials such as glass are used. These substrate materials are formed into a disk-shaped substrate by an injection molding method or the like. If necessary, a groove may be formed on the substrate surface.

In the optical recording medium of the present invention, the azo compound represented by the general formula (1) contained in the recording layer is λ
_{Since max} exists near 500 nm, the refractive index at 620 to 690 nm is large, and the absorbance is small, a large reflectance can be obtained. Moreover, since the refractive index of 770 to 830 nm is large and the absorption is small, the currently used 770 to 830 n is used.
CD player or CD- equipped with m semiconductor laser
It can also be played on a ROM player.

The azo compound used in the present invention is the azo compound represented by the above formula (1). In the substituent of the formula (1), the halogen atom is fluorine, chlorine,
Bromine and iodine are preferred, and fluorine, chlorine and bromine are preferred. As the substituted or unsubstituted alkyl group, a linear or branched alkyl group, an alkoxyalkyl group, an alkoxyalkoxyalkyl group, an alkoxyalkoxyalkoxyalkyl group, an alkoxycarbonylalkyl group,
Alkoxycarbonyloxyalkyl group, alkoxyalkoxycarbonyloxyalkyl group, hydroxyalkyl group, hydroxyalkoxyalkyl group, hydroxyalkoxyalkoxyalkyl group, cyanoalkyl group,
Acyloxyalkyl group, acyloxyalkoxyalkyl group, acyloxyalkoxyalkoxyalkyl group, halogenated alkyl, sulfone alkyl group, alkylcarbonylaminoalkyl group, alkylsulfonaminoalkyl group, sulfonamidoalkyl group, alkylaminoalkyl group, aminoalkyl group, or Examples thereof include an alkylsulfone alkyl group.

Examples of the linear or branched alkyl group include a hydrocarbon group having 1 to 15 carbon atoms. In consideration of workability by coating on a polycarbonate, acryl, epoxy, polyolefin substrate or the like, a methyl group or an ethyl group is used. Base, n-
Propyl, iso-propyl, n-butyl, sec-butyl, t-butyl, n-pentyl, iso-pentyl, 2-methylbutyl, 1-methylbutyl, neo-pentyl, 1,
2-dimethylpropyl group, 1,1-dimethylpropyl group, cycl
o-pentyl group, n-hexyl group, 4-methylpentyl group, 3-
Methylpentyl group, 2-methylpentyl group, 1-methylpentyl group, 3,3-dimethylbutyl group, 2,3-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, 1,
2-dimethylbutyl group, 1,1-dimethylbutyl group, 3-ethylbutyl group, 2-ethylbutyl group, 1-ethylbutyl group, 1,2,
2-trimethylbutyl group, 1,1,2-trimethylbutyl group, 1-
Ethyl-2-methylpropyl group, cyclo-hexyl group, n-heptyl group, 2-methylhexyl group, 3-methylhexyl group,
4-methylhexyl group, 5-methylhexyl group, 2,4-dimethylpentyl group, n-octyl group, 2-ethylhexyl group, 2,
5-dimethylhexyl group, 2,5,5-trimethylpentyl group,
2,4-dimethylhexyl group, 2,2,4-trimethylpentyl group, n-nonyl group, n-decyl group, 4-ethyloctyl group, 4-
Ethyl-4,5-dimethylhexyl group, n-undecyl group, n-
Dodecyl group, 1,3,5,7-tetraethyloctyl group, 4-butyloctyl group, 6,6-diethyloctyl group, n-tridecyl group, 6-methyl-4-butyloctyl group, n-tetradecyl group, n -Pentadecyl group, 3,5-dimethylheptyl group, 2,6-
Dimethylheptyl group, 2,4-dimethylheptyl group, 2,2,5,
Examples thereof include a 5-tetramethylhexyl group, a 1-cyclo-pentyl-2,2-dimethylpropyl group, and a 1-cyclo-hexyl-2,2-dimethylpropyl group.

Examples of alkoxyalkyl groups are methoxymethyl group, ethoxymethyl group, propoxymethyl group, butoxymethyl group, methoxyethyl group, ethoxyethyl group, propoxyethyl group, butoxyethyl group, n-hexyloxyethyl group, 4-methylpentoxyethyl group,
1,3-dimethylbutoxyethyl group, 2-ethylhexyloxyethyl group, n-octyloxyethyl group, 3,5,5-trimethylhexyloxyethyl group, 2-methyl-1-iso-propylpropoxyethyl group, 3- Methyl-1-iso-propylbutyloxyethyl group, 2-ethoxy-1-methylethyl group, 3-
Examples thereof include those having 2 to 15 carbon atoms such as a methoxybutyl group, a 3,3,3-trifluoropropoxyethyl group, and a 3,3,3-trichloropropoxyethyl group.

Examples of alkoxyalkoxyalkyl groups include methoxyethoxyethyl group, ethoxyethoxyethyl group, propoxyethoxyethyl group, butoxyethoxyethyl group, hexyloxyethoxyethyl group, 1,2-dimethylpropoxyethoxyethyl group, 3- Methyl-1-iso-
Butylbutoxyethoxyethyl group, 2-methoxy-1-methylethoxyethyl group, 2-butoxy-1-methylethoxyethyl group, 2- (2'-ethoxy-1'-methylethoxy) -1-methylethyl group, 3 A 3,3,3-trifluoropropoxyethoxyethyl group and a 3,3,3-trichloropropoxyethoxyethyl group. Examples of the alkoxyalkoxyalkoxyalkyl group include a methoxyethoxyethoxyethyl group, an ethoxyethoxyethoxyethyl group, a butoxyethoxyethoxyethyl group, a 2,2,2-trifluoroethoxyethoxyethoxyethyl group, and a 2,2,2-trichloroethoxy group. Examples thereof include an ethoxyethoxyethyl group.

Examples of alkoxycarbonylalkyl groups include methoxycarbonylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, methoxycarbonylethyl group, ethoxycarbonylethyl group, butoxycarbonylethyl group, 2,2,3,3- Examples thereof include a tetrafluoropropoxycarbonylmethyl group and a 2,2,3,3-tetrachloropropoxycarbonylmethyl group. Examples of the alkoxycarbonyloxyalkyl group include a methoxycarbonyloxyethyl group, an ethoxycarbonyloxyethyl group, a butoxycarbonyloxyethyl group, a 2,2,2-trifluoroethoxycarbonyloxyethyl group, and a 2,2,2-
Examples thereof include trichloroethoxycarbonyloxyethyl group. Examples of the alkoxyalkoxycarbonyloxyalkyl group include a methoxyethoxycarbonyloxyethyl group, an ethoxyethoxycarbonyloxyethyl group, a butoxyethoxycarbonyloxyethyl group, a 2,2,
Examples thereof include a 2-trifluoroethoxyethoxycarbonyloxyethyl group and a 2,2,2-trichloroethoxyethoxycarbonyloxyethyl group.

Examples of the hydroxyalkyl group include 2-hydroxyethyl group, 4-hydroxyethyl group, 2-hydroxy-3-methoxypropyl group, 2-hydroxy-3-chloropropyl group, 2-hydroxy-3-ethoxy group. Examples thereof include a propyl group, a 3-butoxy-2-hydroxypropyl group, a 2-hydroxy-3-phenoxypropyl group, a 2-hydroxypropyl group and a 2-hydroxybutyl group. Examples of hydroxyalkoxyalkyl groups include hydroxyethoxyethyl group, 2- (2'-hydroxy-1'-methylethoxy) -1-methylethyl group, 2- (3'-fluoro-2'-hydroxypropoxy) ethyl group. Group, 2- (3'-chloro-2'-hydroxypropoxy) ethyl group and the like, and examples of the hydroxyalkoxyalkoxyalkyl group include hydroxyethoxyethoxyethyl group, [2 '-(2'-hydroxy-1 '-Methylethoxy) -1'-methylethoxy] ethoxyethyl group, [2'-(2'-fluoro-
1'-hydroxyethoxy) -1'-methylethoxy] ethoxyethyl group, [2 '-(2'-chloro-1'-hydroxyethoxy)
-1'-Methylethoxy] ethoxyethyl group and the like.

Examples of the cyanoalkyl group include 2-cyanoethyl group, 4-cyanobutyl group, 2-cyano-3-methoxypropyl group, 2-cyano-3-chloropropyl group and 2-cyano-3 group.
-Ethoxypropyl group, 3-butoxy-2-cyanopropyl group, 2-cyano-3-phenoxypropyl group, 2-cyanopropyl group, 2-cyanobutyl group and the like. Examples of the acyloxyalkyl group, acetoxyethyl group, propionyloxyethyl group, butyryloxyethyl group, valeryloxyethyl group, 1-ethylpentylcarbonyloxyethyl group, 2,4,4-trimethylpentylcarbonyloxyethyl group , 3-fluorobutyryloxyethyl group, 3-chlorobutyryloxyethyl group and the like.

Examples of the acyloxyalkoxyalkyl group are acetoxyethoxyethyl group, propionyloxyethoxyethyl group, valeryloxyethoxyethyl group, 1-ethylpentylcarbonyloxyethoxyethyl group and 2,4,4-trimethylpentylcarbonyloxy group. Ethoxyethyl group, 2-fluoropropionyloxyethoxyethyl group, 2-chloropropionyloxyethoxyethyl group and the like, examples of the acyloxyalkoxyalkoxyalkyl group, acetoxyethoxyethoxyethyl group, propionyloxyethoxyethoxyethyl group,
Valeryloxyethoxyethoxyethyl group, 1-ethylpentylcarbonyloxyethoxyethoxyethyl group, 2,
4,4-Trimethylpentylcarbonyloxyethoxyethoxyethyl group, 2-fluoropropionyloxyethoxyethoxyethyl group, 2-chloropropionyloxyethoxyethoxyethyl group and the like can be mentioned. Examples of the halogenated alkyl group include a chloromethyl group, a chloroethyl group,
2,2,2-trifluoroethyl group, trifluoromethyl group,
Examples thereof include bromomethyl group and methyl iodide group.

Examples of the sulfone alkyl group include a sulfone methyl group, a sulfone ethyl group, a sulfone propyl group and the like. Examples of the alkylcarbonylaminoalkyl group include a methylcarbonylaminoethyl group, an ethylcarbonylaminoethyl group, a propylcarbonylaminoethyl group, a cyclohexylcarbonylaminoethyl group,
Examples thereof include succiniminoethyl group. Examples of the alkyl sulfone aminoalkyl group include a methyl sulfone aminoethyl group, an ethyl sulfone aminoethyl group, a propyl sulfone aminoethyl group and the like. Examples of the sulfonamide alkyl group include a sulfonamide methyl group, a sulfonamide ethyl group, and a sulfonamide propyl group.

Examples of alkylaminoalkyl groups are:
Examples thereof include N-methylaminomethyl group, N, N-dimethylaminomethyl group, N, N-diethylaminomethyl group, N, N-dipropylaminomethyl group and N, N-dibulaminomethyl group. Examples of aminoalkyl groups include aminomethyl groups,
Examples thereof include aminoethyl group and aminopropyl group. Examples of the alkyl sulfone alkyl group include a methyl sulfone methyl group, an ethyl sulfone methyl group, a butyl sulfone methyl group, a methyl sulfone ethyl group, an ethyl sulfone ethyl group, a butyl sulfone ethyl group, 2,2,3,3-tetrafluoropropyl Examples thereof include a sulfonemethyl group and a 2,2,3,3-tetrachloropropylsulfonemethyl group.

Examples of the substituted or unsubstituted alkoxy group are alkoxy groups having the same substituents as the above-mentioned alkyl groups, preferably methoxy group, ethoxy group, n-propoxy group, iso-propoxy group. Group, n-butoxy group, iso-butoxy group, sec-butoxy group, t-butoxy group,
Lower alkoxy groups such as n-pentoxy group, iso-pentoxy group, neo-pentoxy group and 2-methylbutoxy group are exemplified. Examples of substituted or unsubstituted aryl groups include
An aryl group having the same substituents as the above-mentioned alkyl groups, preferably a phenyl group, a nitrophenyl group, a cyanophenyl group, a hydroxyphenyl group, a methylphenyl group, a trifluoromethylphenyl group, a naphthyl group, and a nitro group. Examples thereof include a naphthyl group, a cyanonaphthyl group, a hydroxynaphthyl group, a methylnaphthyl group and a trifluoromethylnaphthyl group.

Examples of the substituted or unsubstituted acyl group are acyl groups having the same substituents as the above-mentioned alkyl groups, preferably formyl group, methylcarbonyl group, ethylcarbonyl group, n-propyl group. Carbonyl group, iso-propylcarbonyl group, n-butylcarbonyl group, iso-butylcarbonyl group, sec-butylcarbonyl group, t-butylcarbonyl group, n-pentylcarbonyl group,
Examples include iso-pentylcarbonyl group, neo-pentylcarbonyl group, 2-methylbutylcarbonyl group, nitrobenzylcarbonyl group and the like. Examples of the substituted or unsubstituted alkylcarboxyl group are alkylcarboxyl groups having the same substituents as the above-mentioned alkyl groups, preferably methylcarboxyl group, ethylcarboxyl group, n-propylcarboxyl group, iso -Propyl carboxyl group, n-butyl carboxyl group, iso-butyl carboxyl group, sec-butyl carboxyl group, t-butyl carboxyl group, n-pentyl carboxyl group, iso-pentyl carboxyl group, neo-pentyl carboxyl group, 2-methyl Examples thereof include lower alkylcarboxyl groups such as butylcarboxyl group.

Examples of the substituted or unsubstituted aralkyl group are aralkyl groups having the same substituents as the above-mentioned alkyl groups, preferably benzyl group, nitrobenzyl group, cyanobenzyl group, hydroxybenzyl group. , Methylbenzyl group, trifluoromethylbenzyl group, naphthylmethyl group, nitronaphthylmethyl group, cyanonaphthylmethyl group, hydroxynaphthylmethyl group, methylnaphthylmethyl group, trifluoromethylnaphthylmethyl group and the like. Examples of the substituted or unsubstituted alkylcarbonylamino group include an alkylcarbonylamino group having the same substituent as the above-mentioned alkyl group, preferably a methylcarbonylamino group, an ethylcarbonylamino group, an n-propyl Carbonylamino group, iso-propylcarbonylamino group, n-butylcarbonylamino group, iso-butylcarbonylamino group, sec-butylcarbonylamino group, t-butylcarbonylamino group, n-pentylcarbonylamino group, iso-pentylcarbonyl Amino group, neo-pentylcarbonylamino group, 2-
And lower alkylcarbonylamino groups such as methylbutylcarbonylamino group, cyclohexylcarbonylamino group, and succinimino group.

Examples of the substituted or unsubstituted alkylsulfonamino group are alkylsulfonamino groups having the same substituents as the above-mentioned alkyl groups, preferably methylsulfonamino group, ethylsulfonamino group, n-propylsulfonamino group, iso-propylsulfonamino group, n-butylsulfonamino group, iso-butylsulfonamino group, sec-butylsulfonamino group, t-butylsulfonamino group, n-pentylsulfonamino group, is
and lower alkylsulfonamino groups such as o-pentylsulfonamino group, neo-pentylsulfonamino group, 2-methylbutylsulfonamino group, and cyclohexylsulfonamino group. Examples of the substituted or unsubstituted alkylamino group include an alkylamino group having the same substituent as the above-described alkyl group, preferably, an N-methylamino group, an N, N-dimethylamino group, And lower alkylamino groups such as N, N-diethylamino group, N, N-dipropylamino group and N, N-dibutylamino group.

Examples of the substituted or unsubstituted alkylsulfone group are alkylsulfone groups having the same substituents as the above-mentioned alkyl groups, preferably methylsulfone group, ethylsulfone group and n-propylsulfone group. Group, iso-propyl sulfone group, n-butyl sulfone group, is
o-butyl sulfone group, sec-butyl sulfone group, t-butyl sulfone group, n-pentyl sulfone group, iso-pentyl sulfone group, neo-pentyl sulfone group, 2-methylbutyl sulfone group, 2-hydroxyethyl sulfone group, And lower alkylsulfone groups such as a 2-cyanoethylsulfone group. Examples of the substituted or unsubstituted alkenyl group are alkenyl groups having the same substituents as the above-described alkyl groups, preferably, propenyl group, 1-butenyl group, iso-butenyl group, 1-pentenyl group , 2-pentenyl group, 2-methyl-1-butenyl group, 3-methyl-1-butenyl group, 2-methyl-2-butenyl group, 2,2-dicyanovinyl group,
2-cyano-2-methylcarboxyl vinyl group, 2-cyano-2
-Lower alkenyl groups such as methylsulfonevinyl groups.

Examples of the substituted or unsubstituted alkylthio group are alkylthio groups having the same substituents as the above-mentioned alkyl groups, preferably a methylthio group,
Ethylthio, n-propylthio, iso-propylthio, n-butylthio, iso-butylthio, sec-butylthio, t-butylthio, n-pentylthio, iso-pentylthio, neo-pentylthio, 2- And lower alkylthio groups such as methylbutylthio group and methylcarboxylethylthio group. Examples of the substituted or unsubstituted alkylazomethine group include an alkylazomethine group having the same substituent as the above-mentioned alkyl group, preferably a methylazomethine group, an ethylazomethine group, or an n-
Propylazomethine group, iso-Propylazomethine group, n-
Butylazomethine group, iso-butylazomethine group, sec-butylazomethine group, t-butylazomethine group, n-pentylazomethine group, iso-pentylazomethine group, neo-pentylazomethine group, 2-methylbutylazomethine group, hydroxyethylazomethine And lower alkylazomethine groups such as a group.

Examples of the substituted or unsubstituted alkylaminosulfone group are alkylaminosulfone groups having the same substituents as the above-mentioned alkyl groups, preferably N-methylaminosulfone group and N-ethyl. Amino sulfone group, N- (n-propyl) amino sulfone group, N- (iso-
Propyl) aminosulfone group, N- (n-butyl) aminosulfone group, N- (iso-butyl) aminosulfone group, N- (sec
-Butyl) aminosulfone group, N- (t-butyl) aminosulfone group, N- (n-pentyl) aminosulfone group, N- (iso
-Pentyl) amino sulfone group, N- (neo-pentyl) amino sulfone group, N- (2-methylbutyl) amino sulfone group, N- (2-hydroxyethyl) amino sulfone group, N- (2
-Cyanoethyl) lower alkylaminosulfone group such as aminosulfone group.

Examples of R ₁ and R ₄ or R ₂ and R ₆ forming a ring via a linking group include —CH ₂ CH ₂ — _, —CH ₂ CH ₂ C
H _2- , -CH ₂ CH (Cl)-, -CH ₂ C (= O) CH _2- , -CH ₂ C (= O)-,-CH ₂ CH
₂ C (= O)-, -CH ₂ CH (F)-, -CH ₂ CH (OH)-. Further, as an example in which R ₁ and R ₂ form a ring via a linking group, -CH ₂ CH ₂ OCH ₂ CH _2- , -CH ₂ CH ₂ NHCH ₂ CH _2- , -CH ₂ CH ₂ N ( C
H ₃ ) CH ₂ CH _2- , -CH ₂ C (= O) OC (= O) CH ₂ -,-CH ₂ C (= O) NHC (= O) CH
_2- , -CH ₂ C (= O) N (CH ₃ ) C (= O) CH _2- , -CH ₂ CH ₂ CH ₂ CH ₂ CH _2- and the like can be mentioned. The compound represented by the general formula (1) of the present invention is produced as follows by a known method. That is, the amine component represented by the general formula (2) (chemical formula 3) is diazotized,
The azo compound represented by the general formula (1) is obtained by adding to the solution of the coupling component represented by the general formula (3) (Chemical Formula 3) and performing a coupling reaction.

[0028]

Embedded image [In the above formula, R _{1 to} R ₇ and X have the same meanings as in the case of formula (1)]

In the present invention, 620 to 690 nm and 770
In order to improve the recording sensitivity to ˜830 nm, an azo compound represented by the general formula (1) and a light absorbing compound having a maximum absorption wavelength at 650 to 900 nm may be mixed and used. In this case, the light absorbing compound having the maximum absorption wavelength in the range of 650 to 900 nm is 0.1 to 0.1% with respect to the azo compound.
Mix 50% by weight. If this light absorbing compound is mixed in an amount of more than 50% by weight, it is 630 to 690 nm and 770 to 830 nm.
The absorption coefficient of the recording layer in nm becomes large, which may reduce the reflectance of the reproducing characteristic. Also, 0.1
630 to 690 nm and 770 to 830 n at weight% or less
Since the absorption coefficient of the recording layer at m is too small, the recording sensitivity is reduced, and there is a risk of recording failure. However, 690 to
When a light absorbing compound having a sharp absorption maximum at 740 nm is used, it is 0.1 to 15 with respect to the azo compound.
0% by weight can be mixed.

The light absorbing compound used in the present application is 65
Any dye having a maximum absorption wavelength of 0 to 900 nm may be used, and pentamethine cyanine dyes, heptamethine cyanine dyes, indophenol dyes, phthalocyanine dyes, naphthalocyanine dyes, pyrylium dyes, thiopyrylium dyes, azurenium. Dyes, triphenylmethane dyes, xanthene dyes, induslen dyes, indigo dyes, thioindigo dyes, merocyanine dyes, thiazine dyes, acridine dyes, oxazine dyes and the like. These dyes may be used alone or in combination of two or more. Among them, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, azo dyes and the like, which are sufficiently soluble in a coating solvent that does not damage the substrate described later, are suitable.

Examples of the cyanine dyes include 1,
3,3,1 ', 3', 3'- Hexamethyl-2,2 '-(4,5,4', 5'-dibenzo) indodicarbocyanine perchlorate, 3,3'-diethyl-2,2 '-(6,7,6', 7'-Dibenzo) thiadicarbocyanine iodide, 3,3'-diethyl-2,2'-selenice carbocyanine iodide, 1,3 '-, diethyl-4 , 2'-Quinoxadicarbocyanine iodide, 3,3 ', 9-triethyl-2,2'-(4,5,4 ', 5'-dibenzo) thiadicarbocyanine bromide, 1,1'- Examples thereof include diethyl-2,4'-quinodicarbocyanine iodide and 1,3'-diethyl-4,2'-quinothiadicarbocyanine iodide. Examples of the phthalocyanine dye include compounds represented by the following chemical formulas (a) to (j) (Chemical Formulas 4 to 8).

[0032]

Embedded image

[0033]

Embedded image

[0034]

[Chemical 6]

[0035]

[Chemical 7]

[0036]

Embedded image In addition, in the compounds (b) to (d) and (h) to (j), Br and the like are substituted on the benzene ring of phthalocyanine. If necessary, additives such as a quencher and an ultraviolet absorber can be mixed with these compounds or dyes, or they can be introduced as a substituent. For example, the additives include those represented by the following general formulas (4) to (10) (chemical formula 9).

[0037]

Embedded image

In the above formula, A and A'are atomic groups forming a benzene ring or a substituted benzene ring, or forming a naphthalene ring or a substituted naphthalene ring, and may be the same or different. As these substituents,
Alkyl group, alkoxy group, hydroxy group, carboxyl group, halogen atom, aryl group, alkylcarboxyl group, alkylalkoxyl group, aralkyl group, alkylcarbonyl group, sulfonate alkyl group bonded to metal ion, nitro group, amino group, alkylamino Group, phenylethylene group and the like. These substituents may be singular or plural. R _{10 to} R ₃₂ are a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a hydroxy group, a carboxyl group, a halogen atom, a substituted or unsubstituted allyl group, a substituted or unsubstituted alkylcarboxyl group, A substituted or unsubstituted alkylalkoxyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkylcarbonyl group, a sulfonate alkyl group bound to a metal ion, a nitro group, an amino group, a substituted or unsubstituted alkylamino group, Examples thereof include a substituted or unsubstituted phenyl group and a substituted or unsubstituted phenylethylene group. M is Ni, Co, Mn, Cu, Pd
And transition metals such as Pt. M has a charge,
It may have a cation and a salt structure. a represents the valence of the ionic substance and is a positive integer including 0. Z represents a cation, a = b × c, and when a = 0, b × c = 0 and Z
Does not exist and the compound becomes neutral.

These compounds and dyes have a recording layer having a thickness of 50 to 500 nm, preferably 100 to 150 nm, formed on a substrate by a coating method such as a spin coating method or a casting method, a sputtering method, a chemical vapor deposition method or a vacuum vapor deposition method. To form. Particularly in the coating method, a coating solvent in which a dye is dissolved or dispersed is used, and it is preferable to select a solvent that does not damage the substrate. For example, alcohol solvents such as methanol, aliphatic hydrocarbon solvents such as hexane and octane, cyclic hydrocarbon solvents such as cyclohexane, aromatic hydrocarbon solvents such as benzene, halogenated hydrocarbon solvents such as chloroform, An etherified hydrocarbon solvent such as dioxane, a cellosolve solvent such as methyl cellosolve, a ketone solvent such as acetone, an ester solvent such as ethyl acetate, etc. are used alone or in combination. The recording layer is not limited to one layer, but may be formed of a multi-layered structure of a plurality of compounds, or the compound may be a thin polymer layer, for example, preferably 5
It can also be used by dispersing it at a concentration of about 0% or more. The recording layer containing the azo compound and the recording layer containing the light absorbing compound may be different from each other. If a solvent that does not damage the substrate cannot be selected, sputtering, chemical vapor deposition, vacuum vapor deposition, etc. are effective.

Next, a thickness of 50 to 300 n is formed on the recording layer.
m, preferably a reflective layer having a thickness of 100 to 150 nm. The material of the reflective layer has a sufficiently high reflectance at the wavelength of the reproduction light, such as Au, Al, Ag, Cu, Zn,
Metals of Ti, Cr, Ni, Pt, Ta, Cr and Pd can be used alone or as an alloy. Among these, Au and Al have a high reflectance and are suitable for the material of the reflective layer. Other than this, for example, Mg, Se, Hf, V,
Nb, Ru, W, Mn, Re, Fe, Co, Rh, I
r, Cu, Zn, Cd, Ga, In, Si, Ge, T
It may contain a metal and a semimetal such as e, Pb, Po, Sn, and Bi. Further, those containing Au as a main component are preferable because a reflection layer having high reflectance can be easily obtained. Here, the main component means that the content rate is 50% or more. It is also possible to use a material other than metal as a reflective layer by alternately stacking low refractive index thin films and high refractive index thin films to form a multilayer film. Examples of the method of forming the reflective layer include a sputtering method, a chemical vapor deposition method, a vacuum vapor deposition method and the like. Further, a reflection amplification layer and an adhesive layer may be provided between the recording layer and the reflection layer in order to increase the reflectance and improve the adhesion.

Further, in the optical recording medium of the present invention, a protective layer can be formed on the reflective layer. The material of the protective layer is not particularly limited as long as it protects the reflective layer from external force. For example, examples of the organic substance include a thermoplastic resin, a thermosetting resin, a UV curable resin, and the like. Among them, the UV curable resin is preferable. Examples of the inorganic substance include SiO ₂ , SiN ₄ , MgF ₂ , and SnO ₂ . A protective layer can be formed by dissolving a thermoplastic resin, a thermosetting resin, or the like in a suitable solvent, applying a coating solution, and drying. The UV-curable resin can be used as it is or by dissolving it in a suitable solvent to prepare a coating solution, and then coating the coating solution and irradiating it with UV light to cure it, thereby forming a protective layer. As the UV curable resin, for example, an acrylate resin such as urethane acrylate, epoxy acrylate, polyester acrylate can be used. These materials may be used alone or as a mixture, or may be used not only as a single layer but also as a multilayer film. As a method of forming the protective layer, a coating method such as a spin coating method or a casting method, a sputtering method, a chemical vapor deposition method, or the like is used as in the recording layer, and the spin coating method is preferable among them.

As the red laser in the present invention, 6
Any laser having a wavelength of 20 to 690 nm may be used. For example, a dye laser capable of wavelength selection in a wide range of visible region, a helium neon laser with a wavelength of 633 nm,
There is a high output semiconductor laser with a wavelength of 680 nm which has been recently developed, and the semiconductor laser is preferable in consideration of mounting on a device. As the near infrared laser, any laser having a wavelength of 770 to 830 nm may be used, but a semiconductor laser used in a commercially available CD player or CD recorder is suitable.

[0043]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited by these examples. Example 1 Of the azo compounds represented by the general formula (1), 0.2 g of the azo compound (S-1) described in Table 1 (Tables 1 to 3) and a pentamethine cyanine dye NK2929 as a light absorbing compound.
(1,3,3,1 ', 3', 3'-hexamethyl-2,2 '-(4,5,4', 5'-dibenzo) indodicarbocyanine perchlorate, manufactured by Japan Photosensitive Dye Research Institute) 0.02 g was dissolved in 10 ml of diacetone alcohol (Tokyo Kasei) to prepare a dye solution. As a substrate, a continuous guide groove (track pitch:
Diameter of 120 mmφ, thickness of 1.2 m
A m-shaped disc (made of polycarbonate resin) was used. A dye solution was spin-coated on this substrate at a rotation speed of 1500 rpm and dried at 70 ° C. for 2 hours to form a recording layer. Au was sputtered on the recording layer using a Balzers sputtering device (CDI-900) to a thickness of 1
A 00 nm reflective layer was formed. Sputtering gas pressure 1.0 ×
It was carried out at 10 ^-2 Torr. Further, an ultraviolet curable resin SD-17 (manufactured by Dainippon Ink and Chemicals, Inc.) was spin-coated on the reflective layer and then irradiated with ultraviolet rays to form a protective layer having a thickness of 6 μm. The sample was measured using a pulse-tick industrial optical disc evaluation device DDU-1000 equipped with a 680 nm red semiconductor laser head and a KENWOOD EFM encoder to obtain a linear velocity of 5.6 m / s and a laser power of 10.
Recorded in mW. After recording, the signal was reproduced using an evaluation device equipped with a 635 nm red semiconductor laser head, and the reflectance was measured. In addition, as a result of performing reproduction evaluation of this recorded sample with a commercially available CD player having a reproduction wavelength of 780 nm, good recording characteristics were shown.

Examples 2 to 6 In Example 1, except that the azo compounds (S-2) to (S-6) shown in Table 1 were used instead of the azo compound (S-1), respectively. An optical recording medium was prepared in the same manner as in Example 1. About the manufactured medium, 68
Optical disc evaluation system DDU-1000 and KENWO manufactured by Pulstic Industrial Co., Ltd. equipped with a 0 nm red laser head.
Using an EFM encoder manufactured by OD, a linear velocity of 5.6 m /
s, laser power was recorded at 10 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 7 In Example 1, the azo compounds (S-7) listed in Table 1 were used.
And heptamethine cyanine dye NK as a light absorbing compound
125 [1,3,3,1 ', 3', 3'-hexamethyl-2,2 '-(4,5,4',
5'-dibenzo) indodicarbocyanine iodide,
An optical recording medium was produced in the same manner except that the product manufactured by Japan Photosensitive Dye Institute was used. 780 nm for the prepared medium
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Examples 8 to 12 In Example 7, the azo compounds shown in Table 1 were used.
An optical recording medium was produced in the same manner except that (S-8) to (S-12) were used. The prepared medium was used in the same manner as in Example 7 (78).
Optical disc evaluation system DDU-1000 and KENWO manufactured by Pulstic Industrial Co., Ltd. equipped with a 0 nm red laser head.
Using an EFM encoder made by OD, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 13 In Example 1, the azo compound (S-13) and the pentamethinecyanine dye NK2627 [3,3'- as a light absorbing compound were used.
An optical recording medium was prepared in the same manner except that diethyl-2,2 ′-(6,7,6 ′, 7′-dibenzo) thiadicarbocyanine iodide, manufactured by Japan Photosensitive Dye Research Institute] was used. Optical disc evaluation device DDU-1 manufactured by Pulstic Industrial Co., Ltd. in which a 780 nm near-infrared semiconductor laser head is mounted on the manufactured medium
000 and KENWOOD EFM encoder were used for recording at a linear velocity of 1.4 m / s and a laser power of 7 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Examples 14 to 18 In Examples 13, respectively, azo compounds (S-14) to (S-18)
An optical recording medium was prepared in the same manner except that was used. As in Example 13, the manufactured medium was equipped with a 780 nm red laser head, an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd., and an EF manufactured by KENWOOD.
Recording was performed at a linear velocity of 1.4 m / s and a laser power of 7 mW using an M encoder. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 19 An optical recording medium was prepared in the same manner as in Example 1 except that the azo compound (S-19) and the phthalocyanine dye represented by the above chemical formula (c) were used as the light absorbing compound. A linear velocity of 5.6 m / s and a laser power of 10 were obtained using an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. equipped with a 680 nm near-infrared semiconductor laser head on the manufactured medium and an EFM encoder manufactured by KENWOOD.
Recorded in mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Examples 20 to 24 In Examples 19, azo compounds (S-20) to (S-24), respectively.
An optical recording medium was prepared in the same manner except that was used. An optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial and a E manufactured by KENWOOD in which a 680 nm red laser head is mounted on the manufactured medium as in Example 19
Recording was performed at a linear velocity of 5.6 m / s and a laser power of 10 mW using an FM encoder. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 25 An optical recording medium was prepared in the same manner as in Example 1 except that the azo compound (S-25) and the phthalocyanine dye represented by the above chemical formula (d) were used as the light absorbing compound. A linear velocity of 5.6 m / s and a laser power of 1 were obtained by using an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. equipped with a 680 nm near-infrared semiconductor laser head and an EFM encoder manufactured by KENWOOD on the manufactured medium.
Recorded at 0 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Examples 26 to 31 In Examples 25 to 31, azo compounds (S-26) to (S-31) are used, respectively.
An optical recording medium was prepared in the same manner except that was used. Similar to Example 25, a 680 nm red laser head was mounted on the manufactured medium, and an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. and E manufactured by KENWOOD.
Recording was performed at a linear velocity of 5.6 m / s and a laser power of 10 mW using an FM encoder. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 32 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-32) was used. On the formed recording layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (b) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The optical recording medium thus prepared was processed in the same manner as in Example 7 with 780n.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KEN equipped with near infrared semiconductor laser head
Using a WOOD EFM encoder, a linear velocity of 2.8 m
/ S, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head,
The reflectance was 31%, which was a good recording property.

Example 33 An optical recording medium was prepared in the same manner as in Example 32 except that the azo compound (S-33) was used. An optical disk evaluation device DD manufactured by Pulstic Industrial Co., Ltd. in which a 780 nm red laser head was mounted on the manufactured medium as in Example 32
Recording was performed at a linear velocity of 2.8 m / s and a laser power of 8 mW using a U-1000 and an EFM encoder manufactured by KENWOOD. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 34 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-34) was used. On the formed recording layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (b) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The optical recording medium thus prepared was subjected to 680n in the same manner as in Example 1.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KEN equipped with near infrared semiconductor laser head
Using a WOOD EFM encoder, a linear velocity of 5.6 m
/ S, laser power was recorded at 10 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 30%, which was a good recording characteristic.

Example 35 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-35) was used. On the formed recording layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (e) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The optical recording medium thus prepared was processed in the same manner as in Example 7 with 780n.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KEN equipped with near infrared semiconductor laser head
Using a WOOD EFM encoder, a linear velocity of 2.8 m
/ S, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head,
The reflectance was 31%, which was a good recording property.

Example 36 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-36) was used. On the formed dye layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (f) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed by spin coating under the same conditions. Was formed to prepare an optical recording medium having two recording layers. The optical recording medium thus prepared was processed in the same manner as in Example 7 with 780n.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KEN equipped with near infrared semiconductor laser head
Using a WOOD EFM encoder, a linear velocity of 2.8 m
/ S, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head,
The reflectance was 30%, which was a good recording property.

Example 37 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-37) was used. On the formed dye layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (g) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The produced optical recording medium was processed at 780 nm in the same manner as in Example 7.
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 31%, which was a good recording characteristic.

Example 38 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-38) was used. On the formed dye layer, a solution obtained by dissolving 0.8 g of the phthalocyanine dye represented by the chemical formula (h) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The produced optical recording medium was processed at 780 nm in the same manner as in Example 7.
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 31%, which was a good recording characteristic.

Example 39 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-39) was used. On the formed dye layer, a solution obtained by dissolving 0.8 g of the phthalocyanine dye represented by the chemical formula (i) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The produced optical recording medium was processed at 780 nm in the same manner as in Example 7.
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 31%, which was a good recording characteristic.

Example 40 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (S-30) was used. On the formed dye layer, a solution of 0.8 g of the phthalocyanine dye represented by the chemical formula (j) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The produced optical recording medium was processed at 780 nm in the same manner as in Example 7.
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 31%, which was a good recording characteristic.

Example 41 An optical recording medium was prepared in the same manner as in Example 1 except that only the azo compound (S-38) was used and the light absorbing compound was not mixed. 680n was applied to the produced medium in the same manner as in Example 1.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KENWOOD equipped with a red laser head
Recording was performed at a linear velocity of 2.8 m / s and a laser power of 9 mW by using an EFM encoder manufactured by. After recording, the same measurement as in Example 1 was performed, and as a result, good recording characteristics were shown.

Examples 42 to 46 Optical recording media were prepared in the same manner as in Example 1 except that the azo compounds (O-1) to (O-5) were used. Recording was performed at a linear velocity of 5.6 m / s and a laser power of 10 mW on the produced medium using an optical disc evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. equipped with a 680 nm red laser head and an EFM encoder manufactured by KENWOOD as in Example 1. did. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics.

Example 47 A recording layer was formed in the same manner as in Example 1 except that the light absorbing compound was not used and only the azo compound (O-2) was used. On the formed dye layer, a solution obtained by dissolving 0.8 g of the phthalocyanine dye represented by the chemical formula (b) in 40 ml of dimethylcyclohexane (Tokyo Kasei) was used, and a dye film was formed under the same conditions by spin coating. Was formed to prepare an optical recording medium having two recording layers. The produced optical recording medium was processed at 780 nm in the same manner as in Example 7.
Optical disc evaluation device DDU-1000 and KENW manufactured by Pulstic Industrial equipped with a near infrared semiconductor laser head
Using an OOD EFM encoder, a linear velocity of 2.8 m /
s, laser power was recorded at 8 mW. After recording, the same measurements as in Example 1 were performed, and as a result, all showed good recording characteristics. Furthermore, when a signal was reproduced using an evaluation device equipped with a 680 nm red semiconductor laser head, the reflectance was 31%, which was a good recording characteristic.

Comparative Example 1 In Example 1, the azo compound was not used, and the pentamethine cyanine dye NK2929 [1,3,3,1 ', 3', 3'-hexamethyl-2,2 '-(4,5, 4 ', 5'-dibenzo) indodicarbocyanine perchlorate, manufactured by Japan Photosensitive Dye Laboratories] was used in the same manner as above to prepare an optical recording medium. A pulse velocity of 5.6 m / s and a laser power of 1 were applied to the produced medium using an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. equipped with a 680 nm red laser head and an EFM encoder manufactured by KENWOOD as in Example 1.
Recorded at 0 mW. After recording, the same measurement as in Example 1 was performed.

Comparative Example 2 In Comparative Example 1, the dye was pentamethine cyanine dye N.
K2627 [3,3'-diethyl-2,2 '-(6,7,6', 7'-dibenzo) thiadicarbocyanine iodide, manufactured by Japan Photosensitive Dye Research Institute] An optical recording medium was produced. 680n was applied to the produced medium in the same manner as in Example 1.
m Pulsick Industrial optical disk evaluation device DDU-1000 and KENWOOD equipped with a red laser head
Recording was performed at a linear velocity of 5.6 m / s and a laser power of 10 mW by using an EFM encoder manufactured by. After recording, the same measurement as in Example 1 was performed.

Comparative Example 3 In Comparative Example 1, the dye was pentamethine cyanine dye N.
An optical recording medium was prepared in the same manner except that K1456 [1,1′-diethyl-2,2′-quinodicarbocyanine iodide, manufactured by Japan Photosensitive Dye Research Institute] was used. A pulse velocity of 1.4 m / s and a laser power were applied to the produced medium using an optical disk evaluation device DDU-1000 manufactured by Pulstic Industrial Co., Ltd. equipped with a 780 nm near infrared semiconductor laser head and an EFM encoder manufactured by KENWOOD as in Example 48. Recorded at 7 mW. After recording, the same measurement as in Example 1 was performed.

Table 2 (Tables 4 to 6) collectively shows the measurement results of the reproduction reflectance and the reproduction reflectance and the error rate in a commercially available CD player having a reproduction wavelength of 780 nm when the above 635 nm red semiconductor laser was used. It was

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

[0072]

[Table 4]

[0073]

[Table 5]

[0074]

[Table 6] The optical recording medium of the present invention using the azo compound represented by the general formula (1) has a higher reproduction reflectance at 635 nm than in the case where only the cyanine dye is used in the recording layer (Comparative Examples 1 to 3). Moreover, it is understood that the error rate at the time of reproduction at 780 nm is also low, and extremely good recording characteristics are exhibited.

[0075]

INDUSTRIAL APPLICABILITY By using an azo compound having an absorption maximum in the range of 450 to 630 nm in the recording layer, the present invention can record and reproduce with a near-infrared laser of 780 nm which has been conventionally used, and has recently moved. This makes it possible to provide a compatible optical recording medium capable of recording / reproducing even with a red laser having a recording / reproducing wavelength of 635 nm or 680 nm.

[Brief description of drawings]

FIG. 1 is a cross-sectional structure diagram of an optical recording medium.

[Explanation of symbols]

 1: substrate 2: recording layer 3: reflective layer 4: protective layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C07D 333/38 C07D 333/42 333/42 409/10 207 409/10 207 307 307 C09B 29/09 A C09B 29/09 Z 8721-5D G11B 7/24 516 G11B 7/24 516 7416-2H B41M 5/26 Y (72) Inventor Takeshi Tsuda 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Hideki Umehara 1190, Kasama-cho, Sakae-ku, Yokohama, Kanagawa Mitsui Toatsu Chemical Co., Ltd. (72) Keisuke Satsuma 1190, Kasama-cho, Sakae-ku, Yokohama, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (5)

[Claims] 1. An optical recording medium having a recording layer, a reflective layer and a protective layer on a substrate, wherein the recording layer has an absorption maximum at a wavelength of 450 to 630 nm represented by the following general formula (1) (Formula 1). An optical recording medium containing an azo compound. Embedded image [In the formula, R ₁ and R ₂ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkenyl group, R ₃ , R ₄ , R ₅ and R ₆ are each independently a hydrogen atom, a halogen atom, a hydroxy group, a carboxyl group, a sulfone group, a sulfonamide group, an amino group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted Alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted acyl group, substituted or unsubstituted alkylcarboxyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted Alkylsulfonamino group, substituted or unsubstituted alkylamino group, substituted or unsubstituted alkylsulfone group, substituted or It represents an unsubstituted alkenyl group,
R ₁ and R ₄ , R ₂ and R ₆ and R ₁ and R ₂ may form a ring through a linking group, and R ₇ , R ₈ and R ₉ are each independently a hydrogen atom, a halogen atom or a hydroxy group. Group, carboxyl group, sulfone group, sulfonamide group, amino group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryl group, substituted or unsubstituted acyl group, substituted or unsubstituted Substituted alkylcarboxyl group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted alkylsulfonamino group, substituted or unsubstituted alkylamino group, substituted or unsubstituted alkylsulfone Group, substituted or unsubstituted alkenyl group, cyano group, nitro group, mercapto group, thiocyano group, chlorosulfone group, substituted or unsubstituted Alkylthio group, a substituted or unsubstituted alkyl azomethine group, a substituted or unsubstituted alkyl amino sulfone group, also, X represents a sulfur atom or an oxygen atom] 2. The recording layer further has a wavelength of 650 to 900.
The optical recording medium according to claim 1, which contains a light absorbing compound having an absorption maximum in nm. 3. The optical recording medium according to claim 2, wherein the light absorbing compound having an absorption maximum at a wavelength of 650 to 900 nm is a phthalocyanine compound. 4. The content of the light absorbing compound having an absorption maximum at a wavelength of 650 to 900 nm is 0.
The optical recording medium according to claim 2, which is 1 to 50% by weight. 5. The reflectance measured from the substrate side with respect to the light selected from the near infrared laser having a wavelength of 770 to 830 nm is 65% or more, and the recording and / or reproduction can be performed by the near infrared laser having a wavelength of 770 to 830 nm. Yes and wavelength 620
The reflectance measured from the substrate side with respect to the light selected from the red laser of ˜690 nm is 15% or more, and the wavelength is 620 to 620.
The optical recording medium according to any one of claims 1 to 4, which is recordable and / or reproducible with a red laser of 690 nm.