JPS63252791A - Optical recording medium - Google Patents

Abstract

PURPOSE:To prevent a recording layer from being deteriorated by reading light, by providing an undercoat layer having a thermal conductivity higher than that of a transparent base on the base, and providing thereon a recording layer comprising an azulenium coloring matter having an azulenium salt nucleus. CONSTITUTION:An undercoat layer 2 having a thermal conductivity higher than that of a transparent base 1 is provided on the base 1, and a recording layer 3 comprising at least one azulenium coloring matter of formula [I], [II] or [III] is provided thereon to produce an optical recording medium. The base is formed of a transparent material such as glass, an acrylic resin, an epoxy resin and a polycarbonate resin. In the general formuals [I], [II] and [III], each of R1, R2, R3, R4, R5, R6 and R7 is hydrogen, a halogen or univalent organic residue, or at least one of the combinations of R1 with R2, R3 with R3, R3 with R4, R4 with R5, R5 with R6 with R7 may form a substd. or unsubstd. condensed ring, A is a divalent organic residue, and Z<-> is an anion residue.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an optical recording medium, and particularly to an optical recording medium for a heat mode 1 that can perform recording and reproduction using a light beam.

[Prior Art] Conventionally, organic optical recording media used in optical discs and optical power-1 technology are made by recording organic light such as organic dyes, organic dye compositions, organometallic complexes, etc. on transparent substrates such as glass and plastics. A recording layer of HEATMO 1 to 1 made of a recording material is provided, and when this recording layer is irradiated with writing light, the writing light is converted into heat, melts and decomposes a part of the recording layer, forms pits, and converts information into recorded with high density. This recorded information is obtained by: 11) scanning the readout light, which is weak by I minutes with respect to the input light, and detecting optical changes such as the reflectance and transmittance of the formed area and the unformed area; Read is performed by

- When using an organic optical recording material as a recording layer, compared to an inorganic optical recording material, it has the following advantages: ■ High productivity because it can be coated, ■ High recording sensitivity, and ■ Recording density. This is advantageous in that it can be seen. However, despite the advantages mentioned above, organic optical recording materials have the disadvantage that the recording layer deteriorates more rapidly due to readout light than inorganic optical recording materials, and the reproduction CAN ratio deteriorates when read out repeatedly. there were.

The reason why organic optical recording materials are more susceptible to deterioration due to readout light is that they have higher thermal insulation properties than inorganic optical recording materials, so the energy of the readout light is stored more easily, and their melting point and decomposition point are lower, so there is less heat storage. The details of whether oxidative deterioration or decomposition is likely to occur are unknown.

Furthermore, it is desirable that the dye used in the above-mentioned organic optical recording material have the following characteristics. That is, 1-It must not be toxic; 2) It must have absorption near 800 nm and a large extinction coefficient; 3) It must have good solubility in organic solvents; 4) It must have a large reflectance in the vicinity of 800nIll when in a thin film state; 5) It must have a thin film state. As a pigment that satisfies these properties, it must be difficult to crystallize6, be stable in ultraviolet and visible light7, be thermally stable8, be stable against moisture9, and be easy to synthesize. A pigment with an azulenium core has been proposed.

The advantages of organic dyes compared to conventionally used inorganic compounds are: 1. 3. Not toxic. This may be because it has good solubility in organic solvents, or it may have a problem with its stability against force, which has been a problem in its commercialization.

[Problems to be Solved by the Invention] The present invention has been made to solve the above-mentioned problems of the prior art. By forming a recording layer containing an azulenium-based dye having an azulenium core thereon, deterioration of the recording layer by readout light can be prevented without sacrificing the advantages of using the azulenium-based dye as a recording layer. The object of the present invention is to provide an optical recording medium that prevents this.

[Means for Solving the Problems] That is, the present invention forms an undercoat layer on a transparent substrate, which has a higher thermal conductivity than the transparent substrate, and has the general formula [I]
, [III, or [I[I].

General formula [II General formula [II] R.

General formula [III] (However, in general formulas [II, [II] and [ml, R1, R2, R3, R4, R5, R61 and R7 represent a hydrogen atom, a halogen atom, or a monovalent organic residue. , or R1 and R2, R2 and R3, R3 and R4, R4 and R
5. At least one combination of R5 and R6 and R6 and R2 may form a substituted or unsubstituted fused ring. A represents a divalent organic residue, and Zo represents an anion residue. ) Hereinafter, the present invention will be explained in detail.

FIG. 1 is a sectional view showing an example of the optical recording medium of the present invention. In FIG. 1, the optical recording medium of the present invention has a transparent substrate 1.
An undercoat layer 2 having a higher thermal conductivity than the transparent substrate 1 is formed thereon, and the undercoat layer 2 is further coated with at least one azulenium-based compound among the compounds represented by the general formula [II, [II] or [IIr]. It is formed by laminating recording layers 3 containing a dye.

The transparent substrate used in the present invention is made of glass, acrylic resin, epoxy resin, polycarbonate resin, or the like.

In the present invention, the undercoat layer is not particularly limited as long as it has higher thermal conductivity than the transparent substrate used and can form a transparent and uniform film, and a wide range of materials can be used. Inorganic films such as carbides, nitrides, fluorides, and sulfides, and organic films such as silicon oxides can be used.

The thermal conductivity of the undercoat layer is usually 5 x 10-' to 8 x I
n-2cat/cm-sec-deg, preferably I
X 10-3~8 X 1O-2cal/cm'scc
-deg range is desirable.

If the thermal conductivity value of the undercoat layer is too close to the thermal conductivity value of the substrate, its effectiveness as a heat dissipation layer will be low, and if it is too high, thermal energy will be absorbed during recording, resulting in a decrease in recording sensitivity.

The thickness of the undercoat layer is usually 50 to 3,000, preferably 100 to 2,000.

Further, in the present invention, the dye used to form the recording layer is an azulenium-based dye having at least one azulenium core.

In particular, the azulenium salt compound described above has the general formula [I
I, [II] or [I[II].

- In the general formula, R1 to 1 (7 does not represent a hydrogen atom, a halogen atom (chlorine atom, bromine atom, iodine atom), or a monovalent organic residue. As a monovalent organic residue, there are a wide range of can be selected from, especially alkyl groups (methyl, ethyl, n-propyl, isopropyl, n-methyl,
t-methyl, n-amyl, n-hexyl, n-octyl, 2-ethylhexyl, t-octyl, etc.), alkoxy groups (methoxy, ethoxy, propoxy, methoxy, etc.), substituted or unsubstituted aryl groups (phenyl , tolyl, xylyl, ethylphenyl, me)~xyphenyl,
ethoxyphenyl, chlorophenyl, nitrophenyl,
dimethylaminophenyl, α-naphthyl, β-naphthyl, etc.), substituted or unsubstituted aralkyl groups (hensyl, 2-phenylethyl, 2-phenyl-1-methylethyl, flomopencyl, 2-fromophenylethyl, methylpencyl, methoxyhensyl, nitropenyl), acyl groups (acetyl, propionyl, phthyryl, valeryl, benzoyl, triooyl, naphthoyl, phthaloyl,
furoyl, etc.), substituted or unsubstituted amino groups (amino, dimethylamino, dimethylamino, dipropylamino, acetylamino, benzoylamino, etc.), substituted or unsubstituted styryl groups (styryl, dimethylaminostyryl, diethylaminostyryl, dipropylamino) styryl, methoxystyryl, ethoxystyryl, methylstyryl, etc.), nitro group, hydroxy group, carboxyl group, cyano group, or substituted or unsubstituted arylazo group (
Phenylazo, α-naphthylazo, β-naphthylazo,
dimethylaminophenylazo, chlorophenylazo, nitrophenylazo, methoxyphenylazo, tolylazo, etc.).

Also, R1 and R2, R2 and R:lI n:l and 11. ,
, lI4 and R5, R5 and R6, and R6 and 1 to 7 may be combined to form a substituted or unsubstituted condensed ring. 5-membered, 6-membered rings as fused rings
Aromatic rings (benzene, naphthalene, chlorobenzene, promohenzene, methylbenzene, ethylbenzene, methoxybenzene,
-xybenzene, etc.), heterocycles (furan ring, benzofuran ring, pyrrole ring, thiophene ring, pyridine ring, quinoline ring, thiazole ring, etc.), and aliphatic rings (dimethylene, trimethylene, tetramethylene, etc.). Zo
represents an anionic residue.

A represents a divalent organic residue bound by a double bond.

Specific examples of dyes containing such A and used in the present invention include those represented by the following general formulas (]) to (11). However, 00 in the formula indicates the following azulenium salt is excluded, and indicates the right side or A excluding Q@ in the formula.

Azulenium salt extraction (Qo) General formula In the formula, R1-R2 have the same definitions as defined above.

R3 1-5 In the formula, R1-R7 have the same definitions as defined above.

In the formula, R'1 to R't represent a hydrogen atom, a halogen atom (chlorine atom, bromine atom, iodine atom) or a monovalent organic residue. Monovalent organic residues can be selected from a wide range of options, but especially alkyl groups (methyl, ethyl,
n-propyl, isopropyl, n-butyl, t-butyl, n-7 mil, n-hexyl, n-octyl, 2-ethylhexyl, a-octyl, etc.), alkoxy groups (methoxy, ethoxy, propoxy, butoxy, etc.), Substituted or unsubstituted aryl groups (phenyl, tolyl, xylyl, ethylphenyl, methoxyphenyl, ethoxyphenyl, chlorophenyl, nitrophenyl, dimethylaminophenyl, α-naphthyl, β-naphthyl, etc.), substituted or unsubstituted aralkyl groups ( Benzyl, 2-phenylethyl, 2-phenyl-1-methylethyl, bromobenzyl, 2-bromophenylethyl, methylbenzyl,
methyl-xybenzyl, nitrobenzyl), acyl groups (acetyl, propionyl, butyryl, /hereryl, benzoyl, trioyl, naphyl-yl, phthaloyl, furoyl, etc.), substituted or unsubstituted amino groups (amine, dimethylamino, diethylamine, (dipropylamino, acetylamino, benzoylamino, etc.), substituted or unsubstituted styryl ((styryl, dimethylaminostyryl, diethyl 7-minostyryl, dipropylaminostyryl, methoxystyryl, ethoxystyryl, methylstyryl, etc.), nitro group, hydroxy group , carboxyl 2 (
, cyan group (or substituted or unsubstituted arylazo group (
Phenylazo, α-naphthylazo, β-naphthylazo,
dimethylaminophenylazo, chlorophenylazo, nitrophenylazo, methoxyphenylazo, tolylazo, etc.).

Also, R'l and R'2+R'2 and R'3. R'3 and R'4+R'4 and R'5. R'5 and R'6 and R'
At least one combination of 6 and R'J may form a substituted or unsubstituted fused ring. It has 5 members as a fused ring.

It is a 6- or 7-membered condensed ring, and includes aromatic rings (benzene, naphthalene, chlorobenzene, bromobenzene, methylbenzene, ethylbenzene, methoxybenzene, ethoxybenzene, etc.), heterocycles (furan ring, benzofuran ring, pyrrole ring) , thiophene ring, pyridine ring, quinoline ring, thiazole ring, etc.), and aliphatic rings (dimethylene, trimethylene, tetramethylene, etc.).

Further, the azulenium salt extraction indicated by Q@ and the azulenium core on the right side in the above formula (3) may be symmetrical or asymmetrical. Zo has the same definition as defined above. R8 represents a hydrogen atom, a nitro group, a cyan group, an alkyl group (methyl, ethyl, propyl, butyl, etc.) or an aryl group (phenyl, tolyl, xylyl, etc.), and n represents an integer of 0.1 or 2. .

In the formula, R1-R7 and Zo have the same definitions as defined above.

■　6 has the same definition as

In the formula, X is pyridine, thiazole, benzothiazole,
Represents a nonmetallic gold group necessary to complete a nitrogen-containing heterocycle such as nandothiazole, oxazole, benzoxazole, naphthoxazole, imidazole, benzimidazole, naphthoimidazole, 2-quinoline, 4-quinoline, inquinoline or indole, Such a heterocycle may be substituted with a halogen atom (J11 element, bromine atom, iodine atom), an alkyl group (methyl, ethyl, propyl, butyl, etc.), an aryl group (phenyl, tolyl, xylyl, etc.), etc. good. R9 is an alkyl group (methyl, ethyl, propyl, butyl, etc.), substituted alkyl group (2-hydroxyethyl, 2-methoxyethyl, 2-ethoxyethyl, 3-hydroxypropyl, 3-
methoxypropyl, 3-ethoxypropyl, 3-chloropropyl, 3-bromopropyl, 3-carboxypropyl, etc.), cyclic alkyl groups (cyclohexyl, cyclopropyl), allyl, aralkyl groups (benzyl, 2-phenylethyl, 3- phenylpropyl, 4-phenolbutyl, α-naphthylmethyl, β-naphthylmethyl), substituted aralkyl groups (methylbenzyl, ethylbenzyl, dimethylbenzyl, trimethylbenzyl, chlorobenzyl,
bromobenzyl, etc.), aryl groups (phenyl, tolyl, xylyl, α-naphthyl, β-naphthyl) or substituted aryl groups (chlorophenyl, dichlorophenyl, trichlorophenyl, ethylphenyl, methoxyphenyl, dimethyl-xyphenyl, aminophenyl, nitrophenyl) , hydroxynoenyl, etc.), m represents an integer of 0 or 1, and Zo has the same definition as defined above.

Ge) Q@= OH-Rh.

In the formula, RIO is a substituted or unsubstituted aryl group (phenyl, tolyl, xylyl, biphenyl, α-naphthyl, β-
Naphthyl, anthralyl, pyrenyl, methoxyphenyl, dimethoxyphenyl, trimethoxyphenyl, ethoxyphenyl, jetoxyphenyl, chlorophenyl, dichlorophenyl, trichlorophenyl, bromophenyl, dibromophenyl, tribromophenyl, ethylphenyl, diethylphenyl, nitrophenyl, amino Phenyl, dimethylaminophenyl, diethylaminophenyl, dibenzylaminophenyl, dipropylaminophenyl, morpholinophenyl, piperidinylphenyl, piperazinophenyl, diphenylaminophenyl, acetylaminophenyl, benzoylaminophenyl, acetylphenyl, benzoylphenyl, cyanphenyl, etc.), and Zo has the same definition as defined above.

(8) Q″f′=CH−R,.

e In the formula, R++ represents a monovalent heterocyclic group derived from a heterocycle such as hafuran, thiophene, benzofuran, thionaphthene, dibenzofuran, carbazole, phenothiazine, phenoxazine, pyridine, etc., and Zo is the same as defined above. have a definition.

(9) Qe= CH-CH= C-RIO
I2 In the formula, R12 is a hydrogen atom, an alkyl group (methyl, ethyl, propyl, butyl, etc.) or a substituted or unsubstituted aryl group (phenyl, tolyl, xylyl, biphenyl,
Ethylphenyl, chlorophenyl, methoxyphenyl,
ethoxyphenyl, nitrophenyl, aminophenyl,
Dimethylaminophenyl, diethylaminophenyl, acetylaminophenyl, α-naphthyl, β-naphthyl,
anthralyl, pyrenyl, etc.). RIG and z'' have the same definitions as defined above.

(10) Q@=CH-C=C-Rh.

e where RIG and Zo have the same definitions as defined above.

In the formula, x2 represents an atomic group necessary to complete the optionally substituted pyran, thiapyran, selenapyran, benzopyran, benzothiapyran, benzoselenapyran, naphthopyran, naphthothiapyran or naphthoselenapyran. ρ
is an integer of 0 or 1. Y represents a sulfur atom, an oxygen atom or a selenium atom. R+3 and R14 are hydrogen atoms, alkyl groups ((methyl, ethyl, propyl, methyl, etc.), alkoxy groups (methoxy, hexyl, propoxy, methoxy, etc.), substituted or unsubstituted aryl groups (phenyl, tolyl, xylyl, chlorophenyl, biphenyl, methoxyphenyl, etc.), substituted or unsubstituted styryl groups (styryl, p-methylstyryl, 0-
chlorostyryl, p-methoxystyryl, etc.), substituted or unsubstituted 4-phenyl, 3-phthalenyl groups (4
-phenyl 1,3-tutagenyl, 4-(p-methylphenyl)-1,3-tutagenyl, etc.) or a substituted or unsubstituted heterocyclic group (quinolyl, pyridyl, carhasolyl, furyl, etc.). Zo is the anion residue, (.

In addition, the anion residue z0 in the formula is a chloride ion, bromide ion, iodide ion, perchlorate ion, benzenesulfonate ion, P-toluenesulfonate ion, methyl sulfate ion, ethyl sulfate. ion, propyl sulfate ion, Te1~rafluoroborate ion, Te)
~raphenylborate ion, hexafluorophosphate ion, pensene sulfinate j11 ion, acetate ion, trifluoroacetate ion, propionacetate ion, benzoate ion, oxalate ion, succinate ion, Malonate ion, oleate ion, stearate ion, citrate ion, -hydrogen dissulfate ion, dihydrogen-phosphate ion, pentachlorostannate ion, chlorosulfonate ion, fluorocarbon Sulfonate ion, trifluoromethanesulfonate ion, hexafluoroantimonate ion, molyfdate ion, tungsdate ion, titanate +1
! ion, anion such as zirconate ion.

Such dyes generally have an absorption peak with a large extinction coefficient near 8 It D nm, have good solubility in organic solvents, and are excellent as optical information recording media.

Next, specific examples of dyes used in the present invention will be given.

Direct E-1 Example of a compound represented by the general formula (2) H3 H3 CH3CH3 Example of a compound represented by the above-mentioned formula (4) CH3GH
+ CH3G)13 (31) C old 2+" CH3 1b 28F4゜2I0 CH3CpOIl"' Compounds represented by general formulas (1) and (2) are manufactured by Angewandte chemie.
) Volume 78.

No, 20. It can be easily obtained by reacting the retyle-like niazurene compound described in J. P., 937 (1988) with squalink or crocodile in an appropriate solvent.

In the compound represented by the general formula (3), the compound where n==o is described in the Journal of the Chemical Society.
1Society), P, 50] (1960), or by heating l-formyruasrene compounds and azulene compounds in a suitable solvent in the presence of a strong acid, or as described in Journal of the Chemical °
Society (Journal of the ch
cn+1calSociety), P, ]724~P
, 1730 (196), or by mixing a 1-ethoxymethylene azulenium salt compound and an azulene compound in a suitable solvent, or as described in Journal of the Chemical Society (Journal of the Chemical Society).
al of Ll+e chemical Society
y), P, 359 (1951), by heating 2-hydroxymethylenecyclohexanone and an azulene compound in a suitable solvent in the presence of a strong acid. In the general formula (3), the compounds of n=1 and n=2 are chemical compounds of the chemical society.
l 5ociety), PJ591~P, :1592
(1951), by mixing an azulene compound and malondialdehydes or glutacondialdehydes in a suitable solvent in the presence of a strong acid.

- The compound represented by the general formula (4) has been published in the Journal of the Chemical Society (, Iournal
of tl+c chemical 5ociety)
, P, 3588 (1961), it can be easily obtained by heating an azulene compound and talyoxal in a suitable solvent in the presence of a strong acid.

・The compound represented by the general formula (5) has been published in the Journal of the Chemical Society.
Lbe chemical 5ocial,y),
It can be obtained by heating a 1,3-sifluormylazulene compound and an azulene compound in a suitable solvent in the presence of a strong acid, as described in P. P., 5 (11 (1960)).

The compound represented by the general formula (6) has been published in the Journal of the Chemical Society.
tt+e chemical 5ociety),
P, ] 63 to P, ] 67 (196), heating a 1-formyl azulene compound and a heterocyclic quaternary ammonium salt compound having an active methyl group in an appropriate solvent. 441.

General formulas (7), (8), (!]) and (l[1
) are listed in the Journal of the Chemical Society.
he cheIIlicalSociety), P
, ] 110-P, ] 117 (1958), Journal of the Chemical Society (, Iour
nal of the chemical 5ocie
ty), P, 494'P, 501 (1960) and Journal of the Chemical Society (1960).
Journal of the chcIIlical
Society), P,: 1579-P, 3593
(1961) by mixing an azulene compound and the corresponding aldehyde compound in a suitable solvent in the presence of a strong acid.

The compound represented by the general formula (11) can be obtained by reacting the -formyl-azulene compound and the compound represented by the general formula (12) in a solvent.

In the formula X2. Y, RI3. R14, Zo and ρ have the same definition as defined above.

Furthermore, the recording layer may contain a binder in addition to the dye. Suitable binders may be selected from a wide variety of resins. Specifically, cellulose esters such as nitrocellulose, phosphocellulose, cellulose sulfate, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose myristate, cellulose valmitate, cellulose acetate/propionate, cellulose acetate/acetate, methyl cellulose, Cellulose ethers such as ethyl cellulose, propyl cellulose, and methyl cellulose, polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl acetal, polyvinyl acetal, polyvinyl alcohol, vinyl resins such as polyvinylpyrrolidone, styrene-tutadiene copolymer, styrene-acrylonitrile copolymers, copolymer resins such as styrene-phthadiene-acrylonitrile copolymers, vinyl chloride-vinyl acetate copolymers, polymethyl methacrylate, polymethyl acrylate, polybutyl acrylate, polyacrylic acid, polymethacrylic acid, polyacrylamide l-', poly Acrylic resins such as acrylonitrile, polyesters such as polyethylene terephthalate, poly(4,4'-isopropylidene, cyphenylene-1,4-cyclohexylene dimethylene carbonate), poly(ethylenedioxy-3,3'- phenylene thiocarbonate), poly(4,4'-isopropylidene phenylene carbonate coated terephthalate),
Poly(4,4'-isopropylidene diphenylene carbonate), poly(4,4'-5ec-phthylidene diphenylene carbonate-1~), poly(4,4'-isopropylidene diphenylene carbonate-floc-oxy) Polyaryl resins such as ethylene), polyamides, polyimides, epoxy resins, phenolic resins, polyolefins such as polyethylene, polypropylene, and chlorinated polyethylene can be used.

Organic solvents that can be used during coating should be in a dispersed state or
Or does it differ depending on whether it is in an amorphous state?
In general, alcohols such as methanol, ethanol, and isopropanol, ketones such as acetate, methyl ethyl ketone, and cyclohexanone, amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and dimethylsulfoxide are commonly used. Nato's Sulfoxy 1~
ethers such as tetrahydrofuran, dioxane, ethylene glycol monomethyl ether, esters such as methyl acetate, ethyl acetate, methyl acetate, chloroform, methylene chloride, dichloroethylene, carbon tetrachloride,
Aliphatic halogenated hydrocarbons such as trichloroethylene, or aromatics such as benzene, toluene, xylene, monochlorobenzene, dichlorobenzene, anisole, etc. can be used.

The general formula [11, [II] or [m] in the recording layer 3
The content of organic dye represented by is usually 70 to 100% by weight.
, preferably 90 to 100% double stitching. If it is less than 70% by weight, it is not possible to obtain sufficient light absorption of the recording layer and sufficient light reflectance for reproduction laser light.

The thickness of the recording layer 3 may vary depending on the purpose of use, but is usually 400 to 5,000 thick, preferably 5 to 1,500 thick.
Someone is appropriate. Note that it is better to be as thin as possible as long as it is possible to stably form a thin film that has sufficient light reflectivity for the recording laser beam.

In the optical recording medium of the present invention, an undercoat layer is formed on a transparent substrate by a vapor deposition method, a sputtering method, a spin code method, etc., and an organic optical recording material is further applied thereon.
It can be easily obtained by coating with spray coating, dip coating, etc. and laminating a recording layer. Further, a protective layer may be provided on the recording layer.

[Function] The optical recording medium of the present invention is formed by forming a subbing layer on a transparent substrate, which has higher thermal conductivity than the transparent substrate, and laminating a recording layer containing an azulenium dye on top of the subbing layer. The undercoat layer functions as a heat dissipation layer, and when reproducing recorded information, the energy of the readout light irradiated to the recording layer is radiated through the undercoat layer, reducing the amount of heat stored in the recording layer. However, it is presumed that deterioration of the organic optical recording material of the recording layer can be prevented.

[Example] The present invention will be described in detail below with reference to Examples.

Example 1 A disk-shaped optical recording medium having the structure shown in FIG. 2 was produced as follows.

AI was placed on a polycarbonate disk transparent substrate 1.1' with an inner diameter of 35 mm, an outer diameter of 200 mm, and a thickness of 1.2 mm.
! A 203 film was deposited by EB evaporation to a thickness of 2500 mm to form the undercoat layers 2 and 2'. The dyes shown in Table 1 below were dissolved in the -L using a predetermined solvent, and a recording layer having a thickness of about 800 mm and a thickness of 3.3' was formed using Subinko 1.

Place the two media thus prepared with the recording layer side inward, and insert a 0.5 mm thick outer circumferential spacer 4. Sandwich the inner spacer 4' to create a hollow structure, and apply two-component polyurethane adhesive 5.
I pasted it together. This optical recording medium has a laser power of 7
Recorded from the substrate side under the conditions of mW, rotation speed 4800 rpm, frequency 2 MHz, and reproduction laser power 0.5 mW.
~ I n+W, and changes in C/N value were examined. The results are shown in Table 2.

Example 2 The subbing layer of Example 1 is Aj! Except for changing from 20x to silicon oxide with a film thickness of 500 nm by spinco 1~.
Samples were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 2.

Example 3 The undercoat layer of Example 1 is made using AI! Except for changing the film thickness from 20:l to 500 epoxy resin by spin code,
Samples were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 2.

5-day Comparative Examples 1 to 3 Conventional samples in which a recording layer was directly formed on the substrate without forming the undercoat layers 2 and 2' as shown in FIG. 3 by the same method as in Examples 1 to 3. was prepared, recorded and reproduced under the same conditions as in Example 1, and changes in C/N value were examined. The results are shown in Table 3.

Table 1 From the results in Tables 2 and 3, polycarbonate disk substrate (thermal conductivity 4.6 x 10'cal/cm-
AR20, layer (
Thermal conductivity 8 x 1O-2cal/cm-sec-de
g) , silicon infusion layer (thermal conductivity 3 x 1O-3
cal/cm・sec・dcg) and epoxy layer (thermal conductivity 5 x 10-'cat/cIII-sec-d
It is recognized that deterioration of the recording layer during reproduction can be prevented by using eg) as a subbing layer of the recording layer.

[Effects of the Invention] As explained above, the optical recording medium of the present invention prevents reproduction deterioration of the recording layer by providing an undercoat layer under the recording layer, which has a higher thermal conductivity than the substrate used. There are some effects that can be done.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the optical recording medium of the present invention, and FIG.
FIG. 3 is a cross-sectional view showing another example of the optical recording medium according to the present invention, and FIG. 3 is a cross-sectional view schematically showing a conventional optical recording medium. 1.1'...Transparent substrate 2.2'...Undercoat layer 3.3'...Recording layer 4...Outer spacer 4'...Inner spacer 5...Adhesive

Claims (2)

[Claims] (1) An undercoat layer having higher thermal conductivity than that of the transparent substrate is formed on a transparent substrate, and at least one of the compounds represented by the general formula [I], [II] or [III] is formed on the undercoat layer. An optical recording medium characterized by being formed by laminating recording layers containing the same. General formula [I] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula [II] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ General formula [III] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ Mathematical formulas, chemical formulas, There are tables etc.▼ (However, in general formulas [I], [II] and [III], R_1, R_2, R_3, R_4, R_5, R_6,
and R_7 represents a hydrogen atom, a halogen atom, or a monovalent organic residue, or R_1 and R_2, R_2 and R_3
, R_3 and R_4, R_4 and R_5, R_5 and R_6, and R_6 and R_7 may form a substituted or unsubstituted fused ring. A represents a divalent organic residue, and Z^e represents an anion residue. ) (2) The thermal conductivity of the undercoat layer is 5×10^-^4 to 8×10
The optical recording medium according to claim 1, which has a range of ^-^2 cal/cm.sec.deg.