JPH0553636B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to a stable optical information recording medium, and more particularly to an optical information recording medium for writing and reading with a high-density energy beam such as a laser beam. [Prior Art] Conventionally, an information recording medium reproducing apparatus is known that records and reproduces information by irradiating a rotating disk-shaped information recording medium with a laser beam. As the recording layer of the information recording medium used in this type of information recording device, metal thin films such as Te, Bi, or chalcogen-based non-quality thin films have been proposed.
However, they are sensitive to oxidation and humidity,
It has drawbacks such as the reflectance to laser light is too high and the utilization rate of laser light is low. Furthermore, it has recently been proposed to use an organic dye thin film whose physical properties can be changed by relatively long wavelength light in the recording layer. Although this organic dye thin film eliminates the above-mentioned drawbacks, organic dyes that generally have absorption characteristics on the long wavelength side have problems such as low stability against heat and light. [Objective] The present invention has been made in view of the above problems, and its object is to provide a stable optical information recording medium with good recording characteristics. [Structure] The recording layer of the present invention is characterized by containing a compound represented by the following general formula [] or []. General formula [] General formula [] However, in each of the above formulas, φ is thiazole,
Represents a heterocycle selected from oxazole, pyrrole, 3,3-dialkylindolenine, imidazole, pyridine, and quinoline, and the heterocycle may be fused with a benzene ring or a naphthalene ring, and the aromatic nucleus may be substituted. groups may be present, Ψ ₁ and Ψ ₂ may be the same or different, each represents a substituted or unsubstituted aromatic ring, or Ψ ₁ and Ψ ₂ together form an aromatic ring. may be used, X represents an anion, and l
represents 0, 1 or 2, m and n are 0,
1, 2 or 3, R ₁ represents hydrogen, an alkyl group, an amino group or a halogen atom, and Y represents an atomic group necessary to form a substituted or unsubstituted 5- or 6-membered ring. In the above general formula, φ representing a heterocycle is specifically represented by the formula It can be expressed as Here, R ₂ alkyl group (for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group,
Isobutyl group, tertiary butyl group, n-amyl group, tertiary amyl group, n-hexyl group, n-octyl group,
tertiary octyl group, etc.), substituted alkyl groups (e.g. 2-hydroxyethyl group, 3-hydroxypropyl group, 4-hydroxybutyl group, 2-acetoxyethyl group, carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group) group, 2-sulfoethyl group, 3-sulfopropyl group, 4-sulfobutyl group, 3-sulfatepropyl group, 4-sulfatebutyl group, N-(methylsulfonyl)-
Carbamylmethyl group, 3-(acetylsulfamyl)propyl group, 4-(acetylsulfamyl)
butyl group, etc.), cyclic alkyl group (e.g., cyclohexyl group, etc.), allyl group ( _CH2 =CH- _CH2
-), aralkyl groups (e.g., benzyl group, phenethyl group, α-naphthylmethyl group, β-naphthylmethyl group, etc.), substituted aralkyl groups (e.g., carboxybenzyl group, sulfobenzyl group, hydroxybenzyl group, etc.) ), represents an aryl group (eg, phenyl group, etc.) or a substituted aryl group (eg, carboxyphenyl group, sulfophenyl group, hydroxyphenyl group, etc.). Further, Z is a substituted or unsubstituted heterocycle, for example, a thiazole series nucleus (for example, thiazole, 4
-Methylthiazole, 4-phenylthiazole,
5-methylthiazole, 5-phenylthiazole, 4,5-dimethylthiazole, 4,5-diphenylthiazole, 4-(2-thienyl)-thiazole, etc.), benzothiazole series nuclei (e.g. benzothiazole, 5- Chlorobenzothiazole, 5-methylbenzothiazole, 6-methylbenzothiazole, 5,6-dimethylbenzothiazole, 5-bromobenzothiazole, 5-phenylbenzothiazole, 5-methoxybenzothiazole, 6-methoxybenzothiazole, 5 ,6-
dimethoxybenzothiazole, 5,6-dioxymethylenebenzothiazole, 5-hydroxybenzothiazole, 6-hydroxybenzothiazole, 4,5,6,7-tetrahydrobenzothiazole, etc.), naphthothiazole series nuclei (e.g. naphtho[2.1 -d] Thiazole, naphtho [1.2-
d] Thiazole, 5-methoxynaphtho [1.2-d]
thiazole, 5-ethoxynaphtho[1.2-d]thiazole, 8-methoxynaphtho[2.1-d]thiazole, 7-methoxynaphtho[2.1-d]thiazole, etc.), thionaphthene[7.6-d]thiazole series nuclei (e.g. 7 -methoxythionaphthene[7.6-d]thiazole), oxazole series nuclei (e.g. 4-methyloxazole, 5-methyloxazole, 4-phenyloxazole, 4.5-
diphenyloxazole, 4-ethyloxazole, 4,5-dimethyloxazole, 5-phenyloxazole), benzoxazole series nuclei (e.g. benzoxazole, 5-chlorobenzoxazole, 5-methylbenzoxazole,
5-phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 5-methoxybenzoxazole, 6
-methoxybenzoxazole, 5-hydroxybenzoxazole, 6-hydroxybenzoxazole, etc.), naphthoxazole series nuclei (e.g. naphtho[2.1-d]oxazole, naphtho[1.2-d]oxazole, etc.), selenazole series nuclei (e.g. 4-methylselenazole, 4-phenylselenazole, etc.), benzoselenazole series nuclei (e.g. benzoselenazole, 5-chlorobenzoselenazole, 5-methylbenzoselenazole, 5,6-dimethylbenzoselenazole,
5-methoxybenzoselenazole, 5-methyl-
6-methoxybenzoselenazole, 5,6-dioxymethylenebenzoselenazole, 5-hydroxybenzoselenazole, 4,5,6,7-tetrahydrobenzoselenazole, etc.), naphthoselenazole series nuclei (e.g. naphtho[ 2.1-d]selenazole, naphtho[1.2-d]selenazole), thiazoline series nuclei (e.g. thiazoline, 4-methylthiazoline, 4-hydroxymethyl-4-methylthiazoline, 4,4-bis-hydroxymethylthiazoline, etc.), Oxazoline series nuclei (e.g. oxazoline), selenazoline series nuclei (e.g. selenazoline), 2-quinoline series nuclei (e.g. quinoline, 6-methylquinoline, 6-chloroquinoline, 6-methoxyquinoline, 6-ethoxyquinoline, 6- hydroxyquinoline), 4-quinoline series nuclei (e.g. quinoline, 6-methoxyquinoline, 7-methylquinoline, 8-methylquinoline), 1-isoquinoline series nuclei (e.g. isoquinoline, 3,4-dihydroisoquinoline), 3-
Nuclei of the isoquinoline series (e.g. isoquinoline),
Nuclei of the 3,3-dialkylindolenine series (e.g. 3,3-dimethylindolenine, 3,3-dimethyl-5-chloroindolenine, 3,3,5-trimethylindolenine, 3,3,7-trimethylindolenine) renin, 3,3-dimethyl-5,7-dichloroindolenine), 3,3-dialkylnaphthopyrrole series nuclei (e.g. 3,3-dimethyl-naphtho[1.2-d]pyrrole, 3,3-dimethyl-
naphtho[2.1-d]pyrrole, 6-chloro-3,
3-dimethyl-naphtho[1.2-d]pyrrole, etc.)
Nuclei of the pyridine series (e.g. pyridine, 5-methylpyridine), nuclei of the benzimidazole series (e.g. 1-ethyl-5,6-dichlorobenzimidazole, 1-hydroxyethyl-5,6-dichlorobenzimidazole, 1-ethyl- 5-chlorobenzimidazole, 1-ethyl-5,6-dibromobenzimidazole, 1-ethyl-5-phenylbenzimidazole, 1-ethyl-5-fluorobenzimidazole, 1-ethyl-5-cyanobenzimidazole, 1 -(β-acetoxyethyl)
-5-cyanobenzimidazole, 1-ethyl-
5-chloro-6-cyanobenzimidazole, 1
-ethyl-5-fluoro-6-cyanobenzimidazole, 1-ethyl-5-acetylbezimidazole, 1-ethyl-5-carboxybenzimidazole, 1-ethyl-5ethoxycarbonylbenzimidazole, 1-ethyl-5- Sulfamylbenzimidazole, 1-ethyl-5-N-ethylsulfamylbenzimidazole, 1-ethyl-5,6-difluorobenzimidazole, 1
-Ethyl-5,6-dicyanobenzimidazole, 1-ethyl-5-ethylsulfonylbenzimidazole, 1-ethyl-5-methylsulfonylbenzimidazole, 1-ethyl-5-trifluoromethylbenzimidazole, 1-ethyl-5
-trifluoromethylsulfonylbenzimidazole, 1-ethyl-5-trifluoromethylsulfinylbenzimidazole, etc.). In the above general formula [] Specific examples include the following 5-membered ring and 6-membered ring compounds. Examples of substituted or unsubstituted aromatic rings represented by Ψ ₁ and Ψ ₂ include phenyl group, 4-chlorophenyl group, 4-dimethylaminophenyl group,
Examples of aromatic rings formed by combining Ψ ₁ and Ψ ₂ include 4-diethylamino group and 4-dibenzylaminophenyl group. etc., and substituents such as an alkyl group, a halogen atom, an alkoxy group, and a substituted or unsubstituted aryl group may be present on each ring. Examples of X representing an anion include halogen ions such as fluorine ion, chlorine ion, bromide ion, and iodide ion, perchlorate ion, benzenesulfonate ion, p-toluenesulfonate ion, and methyl sulfate. ion, ethyl sulfate ion, propyl sulfate ion, and other acid anions. Specific examples of the compounds represented by the above general formulas [] and [] of the present invention are shown below, but the invention is not limited thereto. In addition, the compound of the above general formula of the present invention basically has φ-CH ₃ and can be synthesized by reacting with a diamino compound, dihydroxy compound, or trimethoxy compound forming an intermediate chain. In forming the recording layer of the present invention, the above compounds of the present invention may be used alone, but may further contain other third components such as binders, stabilizers, other pigments, etc., as necessary. You can also do it. In particular, when the recording layer contains a transition metal complex or triarylamino compound that absorbs at long wavelengths as a stabilizer, its photostability is further improved. Further, the compounds of the general formulas [] and [] of the present invention may be used alone or in combination. The thickness of the recording layer is 100 Å to 10 μm, preferably 200 Å
~2μm. As a film forming method, a solution coating method such as dip coating, spray coating, spinner coating, blade coating, roller coating, curtain coating, etc., or other methods such as vapor deposition, CVD, and sputtering method can also be used. Examples of solvents used for coating include ketones such as methyl ethyl ketone, esters such as ethyl acetate, ethers such as methyl cellosolve, alkyl halides such as dichloroethane and chloroform, and aromatics such as toluene and xylene. be able to. Further, the material of the substrate on which the recording layer is provided is not limited in any way, and materials known in this field, such as various plastics, glasses, ceramics, metals, etc., can be used. Further, the shape of the substrate may be tape, disk, drum, belt, etc. depending on the intended use. The recording medium of the present invention basically has a recording layer provided on a substrate, but other layers such as an undercoat layer, an intermediate layer, or a protective layer may be further provided depending on the purpose. Furthermore, guide grooves may be formed in the undercoat layer between the substrate and the recording layer, if necessary. Further, the recording layer may be provided on one or both sides of the substrate, or the recording medium may be arranged in a pair so that the recording layers face each other in a so-called sanderch structure to prevent dust and scratches from forming. can. Furthermore, a reflective layer, various uppermost protective layers, a half mirror layer, etc., which function as a surface when a transparent substrate is used, may be provided on the recording layer, if necessary. However, since the compound of the present invention itself has an extremely high reflectance, it is usually not necessary to use such a base or reflective layer. The undercoat layer (a) improves adhesion, (b) serves as a barrier against water or gas, (c) improves storage stability of the recording layer, and (d)
Improved reflectance, (e) protection of the substrate from solvents and (f)
It is used for purposes such as forming a pre-group. For the purpose of (a), various substances can be used, such as polymeric materials such as ionomer resins, polyamide resins, vinyl resins, natural polymers, silicones, liquid rubbers, and silane coupling agents; For purposes (b) and (c), inorganic compounds such as SiO ₂ , MgF ₂ ,
Metals or metalloids such as SiO, TiO ₂ , ZnO, TiN, SiN, etc. Zn, Cu, S, Ni, Cr, Ge, Se,
Cd, Ag, Al, etc. can be used. For the purpose of (d), metals such as Al, Ag, etc. or organic thin films with metallic luster such as methane dyes, xanthene dyes, etc. can be used, and (e) and (f)
For this purpose, ultraviolet curing resins, thermosetting resins, thermoplastic resins, etc. can be used. The thickness of the undercoat layer is 0.1 to 30 μm, preferably 0.2 to 10 μm.
is appropriate. Further, the protective layer is provided for the purpose of protecting the recording layer from scratches, dust, dirt, etc. and improving the chemical stability of the recording layer, and the same material as that of the undercoat layer can be used for the protective layer. The thickness of the protective layer is suitably 0.1 μm or more, preferably 50 μm or more. Next, the structure of the optical information recording medium according to the present invention will be explained with reference to the drawings. As shown in FIG. 1, the optical information recording medium of the present invention basically comprises a substrate 1 and a recording layer 2 containing the compound of the above formula [] or [] of the present invention. Further, the recording layer can also have a two-layer structure in which a light-reflecting layer and a light-absorbing layer are combined in any order. Furthermore, as shown in FIGS. 2 to 4, the structure shown in FIG. 1 may be further provided with an undercoat layer 3 and/or a protective layer 4. In addition, stabilizers, dispersants,
Flame retardants, lubricants, antistatic agents, surfactants, plasticizers, etc. may also be contained. Furthermore, as another configuration of the optical information recording medium according to the present invention, two recording media having the same configuration as shown in FIGS. It may be a so-called air sand switch structure in which the film is placed inside and sealed, or it may be a so-called close sandwich structure (bonded structure) in which it is bonded with a protective layer 4 interposed therebetween. [Example] The present invention will be further explained with reference to Examples below, but the present invention is not limited thereto. Example 1 The above-mentioned exemplary compound (1) was dissolved in 1,2-dichloroethane to prepare a 0.6% by weight coating solution. This coating solution was coated onto an acrylic substrate provided with guide grooves made of photocurable resin to obtain a recording layer with a thickness of 500 Å.
A protective cover was adhered to the thus obtained recording medium via a spacer. A 0.7 MHz signal was recorded on this recording medium using a semiconductor laser with a wavelength of 780 nm at a beam diameter of 1.6 μm, a linear velocity of 1.4 m/sec, and a recording surface beam power of 3 mW. Furthermore, when we read out the signals recorded by irradiating with a 0.2 mW continuous beam, we obtained a CN ratio of 53 dB. Furthermore, this recording medium was stored in an environment of 50°C and 90% RH for 1000 hours, but no change in characteristics was observed. Examples 2 to 20 Example 1 except that the above-mentioned exemplified compounds shown in the table below were used instead of compound (1) in Example 1.
Each recording medium was produced in the same manner as described above. The results of testing the C/N and storage stability of these recording media are summarized in the table below.

〔effect〕

According to the optical information recording medium of the present invention, a stable recording medium with good recording characteristics (high C/N) could be obtained.

[Brief explanation of the drawing]

1 to 4 are cross-sectional views showing the structure of the optical information recording medium of the present invention. 1... Substrate, 2... Recording layer, 3... Undercoat layer,
4...Protective layer.

Claims (1)

[Claims] 1. An optical information recording medium characterized by having a recording layer containing a compound represented by the following general formula [] or [] on a substrate, general formula [] General formula [] (In the above formula, φ represents a heterocycle selected from thiazole, oxazole, pyrrole, 3,3-dialkylindolenine, imidazole, pyridine, and quinoline, and a benzene ring or a naphthalene ring is fused to the heterocycle. Substituents may also exist on the aromatic nucleus, and Ψ ₁
and Ψ ₂ may be the same or different and each represents a substituted or unsubstituted aromatic ring, or Ψ ₁ and Ψ ₂ may be taken together to form an aromatic ring, and X represents an anion. , l is 0,
1 or 2, m and n represent 0, 1, 2 or 3, R ₁ represents hydrogen, an alkyl group, an amino group or a halogen atom, and Y represents a substituted or unsubstituted 5- or 6-membered ring (represents the atomic group necessary to form).