JP2732274B2 - Optical recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium suitable for writing and recording with a laser beam, particularly a semiconductor laser, and more particularly, to a novel optical recording that can be used in optical disk and optical card technology. It is about media.

2. Description of the Related Art Generally, an optical disk and an optical card are formed by forming small optically detectable (for example, about 1 μ) pits formed in a thin recording layer provided on a substrate into a spiral or circular track. And high-density information can be stored.

To write information on such a disk, a laser focused on the surface of the laser sensitive layer (recording layer) is scanned, and pits are formed only on the surface irradiated with the laser beam. Formed in the form of circular or linear tracks. The laser sensitive layer (recording layer) can absorb laser energy to form optically detectable pits.
For example, in the heat mode recording method, the laser sensitive layer (recording layer) absorbs thermal energy, and small recesses (pits) can be formed at that location by evaporation or melting. In another heat mode recording method, a pit having a density difference that can be optically detected can be formed at that location by absorbing the irradiated laser energy.

Information recorded on this optical disk and optical card is
The laser light is scanned along the track, and the optical change is detected by reading an optical change in a portion where a pit is formed and a portion where a pit is not formed. For example, a laser beam is scanned along a track, and the energy reflected by the disk is monitored by a photodetector. In the portion where the pits are formed, the reflection of laser light is reduced, and the output of the photodetector is reduced. on the other hand,
In the portion where no pit is formed, the laser light is sufficiently reflected, and the output of the photodetector increases.

Optical recording media used for such optical discs and optical cards have so far mainly used inorganic materials such as metal thin films such as aluminum evaporated films, bismuth thin films, tellurium oxide thin films, and chalcogenite-based amorphous glass films. Proposed. These thin films are generally sensitive to light having a wavelength of about 350 to 800 nm and have a high reflectance to laser light, and thus have a drawback such as low utilization of laser light.

For these reasons, in recent years, relatively long wavelengths (for example, 780 n
Organic thin films whose optical properties can be changed with light energy of over m) have been studied. Such an organic thin film is effective in that pits can be formed by a semiconductor laser having an oscillation wavelength of about 780 nm or 830 nm, for example.

However, generally, an organic compound having an absorption characteristic on a long wavelength side has a problem of being unstable to heat.

For example, the handling of optical recording media is not always used only in offices equipped with air conditioning equipment, but it is necessary to consider storage in transport warehouses, temperature rise in drive devices, etc. A medium is desired. In particular, when the optical recording medium is an optical card, it is difficult to take a hollow structure (air sandwich structure) in terms of the thickness and strength of the card, and the opposing substrate is bonded directly on the recording layer with an adhesive. Structure. As the adhesive used at this time, a hot-melt adhesive which is excellent in workability without lowering the writing sensitivity of the recording layer is effective. However, a hot-melt adhesive has a temperature of about 100 ° C. at the time of lamination, although in a short time, so that a recording layer having better heat resistance is desired. Furthermore, optical cards are often handled by individuals and are likely to be handled sparsely. Therefore, optical cards that are excellent in heat stability and other environmental stability are desired.

[Problems to be Solved by the Invention] The present invention has been made in view of such a current situation, and an object thereof is to provide an optical recording medium having a recording layer made of an organic thin film having an absorption band on a long wavelength side. To provide.

Another object of the present invention is to provide an optical recording medium having a recording layer comprising a dye thin film having improved stability even under high temperature and high humidity environmental conditions.

Another object of the present invention is to provide an optical recording medium having improved sensitivity and changes in optical characteristics accompanying recording.

Another object of the present invention is to provide an optical recording medium that can be manufactured by a coating method.

[Means for Solving the Problems] and [Action] That is, the present invention relates to the following general formulas [I], [II], [II]
An optical recording medium comprising a recording layer containing one or more naphtholactam-based compounds represented by [I], [IV] or [V].

(However, in the general formulas [I] to [V], R₁Is a replacement
Or unsubstituted alkyl, cycloalkyl, alkoxy
Represents a di, allyl, aryl or aralkyl group
Then R_TwoAnd R_ThreeIs a hydrogen atom, a halogen atom or a monovalent
Represents an organic residue, R_Four~ R₁₂Is hydrogen atom, halogen atom
Or a monovalent organic residue. R₁₃And R₁₄Also replace
Or an unsubstituted alkyl group, substituted or unsubstituted ant
Or substituted or unsubstituted styryl groups or substituted
Or an unsubstituted heterocyclic group. Y is replaced or not
Divalent hydrocarbon group forming a substituted 5- or 6-membered ring
Is shown. m is 1, 2 or 3, p is 0, 1 or 2, q is 0.1
Or 2, r is 1 or 2, l is an integer of 1 or 2.
You. X Represents an anion residue. Hereinafter, the present invention will be described in detail.

The optical recording medium of the present invention absorbs electromagnetic radiation and receives a thermal action, and the optical action of the above general formula [I], [II], [III], [IV] or [V] which causes an optical change by the thermal action.
Characterized in that it has a recording layer composed of a thin film containing one or more naphtholactam-based compounds represented by

In the general formulas [I], [II], [III], [IV] and [V], R ₁ in the formula is a C ₁ -C ₂₀ -alkyl group (this is a phenyl group, a halogen atom, a C ₁ -C ₄ - alkanoyl group, carboxyl group, C ₁ -C ₄ - alkanoylamino group, C ₁ -C ₄ - alkoxycarbonyl group, C ₁ -C ₄ - alkoxycarbonylamino group or a C ₁ -C ₄ - Arukiruani Substituted by a lino group and / or interrupted by an oxygen atom), for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tertiary butyl group, pentyl group, 2-methylbutyl Group, hexyl group, 2-methylpentyl group, heptyl group, octyl group,
2-ethylhexyl, isooctyl, nonyl, isononyl, decyl, isodecyl, dodecyl, 3,
5,5,7-tetramethylnonyl group, isotridecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group (the names of isooctyl, isononyl, isodecyl and isotridecyl are common names, and oxo synthesis Derived from the alcohol obtained, in this regard, "Ulmans Enticlopedi del Tehnitssien Hemy", 4th edition, Volume 7, 2
Pp. 16-217 and 11, 435-436), benzyl group, 2
-Phenylethyl group, trifluoromethyl group, trichloromethyl group, 1,1,1-trifluoroethyl group, heptafluoropropyl group, 2-methoxyethyl group, 2-ethoxypropyl group, 3-ethoxypropyl group, 3 , 6-Dioxaheptyl group, 3,6-dioxaoctyl group, 3,6,9-trioxadecyl group, propan-2-one-1-yl group, butan-3-one-1-yl group, 2-ethylpentane-3
-On-1-yl group, carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 4-carboxybutyl group, 5-carboxypentyl group, 4-carboxy-3-oxabutyl group, acetylaminomethyl group,
2- (acetylamino) -ethyl group, 2- (butyrylamino) -ethyl group, ethoxycarbonylmethyl group, 2-
(Ethoxycarbonyl) -ethyl group, 3- (methoxycarbonyl) -propyl group, ethoxycarbonylaminomethyl group, 2- (ethoxycarbonylamino) -ethyl group, 4-methylanilinomethyl group, 2- (4-isopropylani Rino) -ethyl groups, for example, C ₅ -C ₇ -cycloalkyl groups (which may be substituted by C ₁ -C ₄ -alkyl groups or halogen atoms), for example cyclopentyl, cyclohexyl, cycloheptyl Group, 3-methylcyclopentyl group, 4-ethylcyclohexyl group, 2,
3-dichlorocyclohexyl groups, and aryl groups (which are substituted by a C ₁ -C ₄ -alkyl group, a C ₁ -C ₄ -alkoxy group, a halogen atom or a C ₁ -C ₄ -dialkylamino group). For example, phenyl, naphthyl, tolyl, 4-methylphenyl, 4-isopropylphenyl, 4-methoxyphenyl, 2,4-dimethoxyphenyl, 2-chlorophenyl, 4-bromo A phenyl group or a 4-dimethylaminophenyl group; an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group; and an allyl group (CH ₂ CHCH—CH ₂ —), an aralkyl group, For example, benzyl group, phenethyl group, α-naphthylmethyl group, β-naphthylmethyl group, carboxybenzyl group, sulfobenzyl group, hydroxybenzyl And the like, but representing each group of the above.

The naphthalene ring to which R ₂ and R ₃ are bonded may be unsubstituted (hydrogen atom), may be substituted by the following group, or may be benzo-fused.

R ₂ and R ₃ represent a hydrogen atom, a halogen atom (a chlorine atom, a fluorine atom, a bromine atom, an iodine atom) or a monovalent organic residue. Examples of the monovalent organic residue, C ₁ -C ₄ - alkyl group, a phenyl group, C ₁ -C ₄ - alkoxy, C ₁ -C ₂₀ alkylthio group, hydroxy group, an amino group, an acylamino group, a nitro group, cyano group, C ₁ -C ₄ - mono- - or dialkylamino group, C ₁ -C ₄ alkylsulfonyl group, C ₁ -C ₄
Alkoxysulfonyl group, phenylsulfonyl group, C ₁ to
C ₄ alkyl phenylsulfonyl group, hydroxy sulfonyl group, an anilino group, C ₁ -C ₄ alkyl anilino group, C ₁ -C ₄
Alkanoyl group, C ₁ -C ₄ alkanoylamino group, C ₁ -C ₄
Alkoxycarbonyl group, C ₁ -C ₄ alkoxycarbonylamino group, a carbamoyl group, C ₁ -C _4-N-mono - or N, N-dialkylcarbamoyl group, sulfamoyl group, C ₁ -C _4-N-mono - or N, N-dialkyl sulfamoylamino group, a ureido group, C ₁ -C ₄ - ureido group substituted by an alkyl group, Funinokishi group, phenylthio group or may be a group represented by the following formula.

R _{4 to} R ₁₂ represent a hydrogen atom, a halogen atom (a chlorine atom, a fluorine atom, a bromine atom, an iodine atom) or a monovalent organic residue.

The monovalent organic residue can be selected from a wide range, and particularly, an alkyl group (methyl, ethyl, n-
Propyl, isopropyl, n-butyl, t-butyl, n
-Amyl, n-hexyl, n-octyl, 2-ethylhexyl, t-octyl, etc.), alkoxy group (methoxy, ethoxy, propoxy, butoxy, etc.), substituted or unsubstituted aryl group (phenyl, tolyl, xylyl, ethylphenyl) , Methoxyphenyl, ethoxyphenyl, chlorophenyl, etrophenyl, dimethylaminophenyl, α-naphthyl, β-naphthyl, etc.), substituted or unsubstituted heterocyclic groups (pyridyl, quinolyl, carbazolyl, furyl, thienyl, pyrazolyl, etc.) Unsubstituted aralkyl groups (benzyl, 2-phenylethyl, 2-phenyl-1-methylethyl, bromobenzyl, 2-bromophenylethyl, methylbenzyl, methoxybenzyl, nitrobenzyl, etc.), acyl groups (acetyl, propionyl, Butyryl, valeryl, benzoyl, trioil, naphthoyl, phthaloyl, furoyl, etc., substituted or unsubstituted amino groups (amino, dimethylamino, diethylamino, dipropylamino, acetylamino, benzoylamino, etc.), substituted or unsubstituted styryl groups (styryl) Dimethylaminostyryl, diethylaminostyryl, dipropylaminostyryl, methoxystyryl, ethoxystyryl, methylstyryl, etc.), nitro group, hydroxy group, mercapto group, thio-
Ether group, carboxyl group, carboxylic acid ester, carboxylic acid amide, cyano group or substituted or unsubstituted arylazo group (phenylazo, α-naphthylazo, β-naphthylazo, dimethylaminophenylazo, chlorophenylazo, nitrophenylazo, methoxyphenylazo, Tolylazo).

R ₁₃ and R ₁₄ represent an alkyl group (eg, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group,
-Butyl group, sec-butyl group, iso-butyl group, t-butyl group, n-amyl group, t-amyl group, n-hexyl group,
n-octyl group, t-octyl group and the like, and further another alkyl group such as a substituted alkyl group (for example, 2-
Hydroxyethyl group, 3-hydroxypropyl group, 4-
Hydroxybutyl group, 2-acetoxyethyl group, carboxymethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 2-sulfoethyl group, 3-sulfopropyl group, 4-sulfobutyl group, 3-sulfopropylpropyl group, 4 -Sulfate butyl group, N- (methylsulfonyl) -carbamylmethyl group, 3- (acetylsulfamyl) propyl group, 4- (acetylsulfamyl) butyl group, etc., cyclic alkyl group (for example, cyclohexyl) Group), an allyl group (CH ₂ CHCH—CH ₂₋ ), an aralkyl group (eg, benzyl group, phenethyl group, α-naphthylmethyl group, β-naphthylmethyl group, etc.), a substituted aralkyl group (eg, carboxybenzyl) Group, sulfobenzyl group, hydroxybenzyl group, etc.). further,
R ₁₃ and R ₁₄ are a substituted or unsubstituted aryl group (for example, a phenyl group, a naphthyl group, a tolyl group, a xylyl group,
Methoxyphenyl, dimethoxyphenyl, trimethoxyphenyl, ethoxyphenyl, dimethylaminophenyl, diethylaminophenyl, dipropylaminophenyl, dibenzylaminophenyl, diphenylaminophenyl, etc.), substituted or unsubstituted Heterocyclic group (for example, pyridyl group, quinolyl group, lepidyl group, methylpyridyl group, furyl group, thienyl group, indolyl group, pyrrole group, carbazolyl group, N-ethylcarbazolyl group, etc.) or substituted or unsubstituted styryl Groups (for example, styryl group, methoxystyryl group, dimethoxystyryl group, trimethoxystyryl group, ethoxystyryl group, dimethylaminostyryl group, diethylaminostyryl group, dipropylaminostyryl group, dibenzylaminostyryl group, dibenzyl E arylsulfonylamino styryl group, 2,2
Diphenylvinyl group, 2-phenyl-2-methylvinyl group, 2- (dimethylaminophenyl) -2-phenylvinyl group, 2- (diethylaminophenyl) -2-phenylvinyl group, 2- (dibenzylaminophenyl)- 2-
Phenylvinyl group, 2,2-di (diethylaminophenyl) vinyl group, 2,2-di (methoxyphenyl) vinyl group, 2,2- (ethoxyphenyl) vinyl group, 2- (dimethylaminophenyl) -2-methyl Vinyl group, 2- (diethylaminophenyl) -2-ethylvinyl group, etc.).

Y is a divalent hydrocarbon radical which forms a 5- or 6-membered ring substituted or unsubstituted _{(-CH 2 -CH 2 -, -} CH 2 -CH 2 -CH 2, —CH ＝ CH—), and these 5- or 6-membered rings may be condensed with a benzene ring, a naphthalene ring or the like.

m represents 1, 2, or 3, p represents 0, 1, or 2, q represents 0, 1, or 2, r represents 1 or 2, and l represents an integer of 1 or 2.

 Also, X Is chlorine ion, bromine ion, iodine ion
Perchlorate ion, nitrate ion, benzene sulfo
Phosphate ion, p-toluenesulfonate ion, methyl
Sulfate ion, ethyl sulfate ion, propyl sulfate
Ion, tetrafluoroborate ion, tetraphenylene
Ruborate ion, hexafluorophosphate ion,
Benzene sulfonate ion, acetate ion, trifluoro
Loacetate ion, propion acetate ion, benzoate
Ion, oxalate ion, succinate ion, malon
Ion, oleate ion, stearate ion
Citrate ion, monohydrogen diphosphate ion, dihydrate
Monophosphate ion, pentachlorostannate ion,
Lorosulfonic acid ion, fluorosulfonic acid ion
Trifluoromethanesulfonate ion, hexaf
Fluoroarsenate ion, hexafluoroantimonate ion
ON, molybdate ion, tungstate ion
Negative ions such as iron, titanate and zirconate ions
Indicates ON.

Hereinafter, specific examples of the naphtholactam-based compound used in the present invention are listed below, but the invention is not limited thereto.

Examples of the compound represented by the general formula [I] Examples of the compound represented by the general formula [II] Examples of the compound represented by the general formula [III] Examples of the compound represented by the general formula [IV] Examples of the compound represented by the general formula [I]  Represented by the above general formulas [I], [II] and [III]
Compounds are disclosed in U.S. Pat.No. 2,734,900.
Similar to the method for synthesizing cyanine,
A compound to be(Where R₁, R_Two, R_ThreeAnd X Means the same as defined above.
To form an intermediate chain with a compound having an active ethylene group.
For example, malondialdehydes or glutacondi
Aldehydes, 2-chloro-1-formylhydroxyethyl
Hydroxy compounds such as lencyclohexane and isophorone
Substance, dihydroxy compound, carbonyl compound, diamino
Reacting with compounds or trimethoxy compounds
Can be synthesized by

The compounds represented by the general formulas [IV] and [V] can be obtained by combining the compound represented by the general formula [VI] and a compound having an active ethylene group with squaric acid or croconic acid forming an intermediate chain and a suitable solvent. It can be easily obtained by reacting in water.

As shown in FIG. 1, the optical recording medium of the present invention comprises a substrate 1
And a recording layer 2 containing a naphtholactam-based compound represented by any one of the above general formulas [I] to [V].

As the substrate 1, polycarbonate, polyester,
Acrylic resin, polyolefin resin, phenol resin,
Plastic such as epoxy resin, polyamide, and polyimide, glass, and metals can be used.

In forming the recording layer 2, the above general formulas [I] to
The naphtholactam-based compound represented by [V] can be used alone or in combination of two or more.
For example, naphtholactam-based, polymethine-based, azulene-based, pyrylium-based, squarium-based, croconium-based, triphenylmethane-based, xanthene-based, anthraquinone-based, cyanine-based, and phthalocyanine-based compounds other than the compounds represented by the general formulas [I] to [V]. , Dioxazine, tetrahydrocholine, triphenothiazine, phenanthrene,
Aminium salt / diimonium salt type, metal chelate complex type dye or the like, or metal and metal compound, for example,
Al, Te, Bi, Sn, In, Se, SnO, TeO ₂ , As, Cd, or the like, or a mixture with an ultraviolet absorber or the like may be dispersed or laminated.

The recording layer 2 is formed on the substrate 1 by various methods such as a coating method and a vapor deposition method. When a coating method is used, it can be formed by applying a solution in which a naphtholactam-based compound is dissolved or dispersed in an organic solvent onto the substrate 1. If necessary, a binder can be mixed in the recording layer to form a film in consideration of film formability and coating film stability.

The organic solvent that can be used at the time of coating varies depending on whether the above-described naphtholactam compound is in a dispersed state or a dissolved state, but is generally an alcohol, ketone, amide, ether, ester, or fat. Solvents such as aromatic halogenated hydrocarbons, aromatics, and aliphatic hydrocarbons can be used.

Examples of the binder include nitrocellulose, ethylcellulose, polystyrene, polyvinylpyrrolidone, polymethyl methacrylate, and polyamide. If necessary, waxes, higher fatty acids, and amides (eg, oleylamide) are used as additives.

Plasticizers such as dioctyl phthalate, dibutyl phthalate, tricresyl phosphate, etc.
An oil agent such as mineral oil or vegetable oil, a dispersant such as sodium alkylbenzenesulfonate, polyoxyethylene alkylphenyl ether and other additives can be appropriately mixed to improve the film-forming property and the stability of the coating layer of the recording layer.

Coating can be performed using a coating method such as dip coating, spray coating, spinner coating, bead coating, Meyer bar coating, blade coating, curtain coating, roller coating, gravure coating, etc. it can.

The content of the naphtholactam compound in the recording layer 2 is usually
40 to 100% by weight, preferably 50 to 100% by weight is desirable.
If it is less than 40% by weight, it is not possible to obtain a sufficient light absorbing property of the recording layer and a sufficient light reflectance with respect to the reproducing laser beam.

The thickness of the recording layer 2 is 100 to 20 μm, preferably 2 to 20 μm.
00Å-1 μm is appropriate. Note that it is preferable that the thin film be as thin as possible if a thin film having sufficient light reflectivity to the recording laser beam can be formed stably.

Further, in the optical recording medium of the present invention, as shown in FIG. 2, a protective layer 3 which is transparent to recording and reproducing laser light can be provided on the recording layer 2. When light is irradiated from the substrate 1 side, the protective layer 3 may be opaque.

Further, as shown in FIG. 3, an undercoat layer 4 may be provided between the substrate 1 and the recording layer 2.

Further, as shown in FIG. 4, it is also possible to use both the protective layer 3 and the undercoat layer 4.

The undercoat layer is (a) improved adhesiveness, (b) a barrier against water or gas, (c) improved storage stability of the recording layer,
It is provided for the purpose of (d) improving the reflectance, (e) protecting the substrate from a solvent, and (f) forming a pre-groove. For the purpose of (a), a polymer material, for example, various materials such as an ionomer resin, a polyamide resin, a vinyl resin, a natural polymer, silicone, a liquid rubber, or various substances such as a silane coupling agent are used. For the purposes of (b) and (c), inorganic compounds other than the above-mentioned polymer materials, for example, SiO ₂ , MgF ₂ , SiO, TiO ₂ , ZnO, Ti
Metals or metalloids, such as N, SiN, for example, Zn, Cu, S, Ni, Cr, G
e, Se, Cd, Ag, Al and the like can be used. For the purpose of (d), a metal such as Al or Ag, or an organic thin film having a metallic luster such as a cyanine dye or a methine dye can be used. For the purposes (e) and (f), an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin, or the like can be used. Undercoat layer thickness is 50 層
100 μm, preferably 200 to 30 μm is suitable.

The protective layer is provided for the purpose of protecting from scratches, dust, dirt, etc., and improving the storage stability and the reflectance of the recording layer, and the same material as that of the undercoat layer may be used. it can. The thickness of the protective layer is suitably 100 ° or more, preferably 1000 ° or more.

In this case, the undercoat layer and / or the protective layer may contain the naphtholactam-based compound of the general formulas [I] to [V] of the present invention. The undercoat layer or the protective layer may contain a stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, and the like.

Further, as another configuration of the optical recording medium according to the present invention, the recording layer 2 is formed by using two recording media having the same configuration shown in FIG. 1 to FIG. A so-called air sandwich structure that is disposed inside and sealed may be used, or a so-called close-contact structure (laminated structure) bonded through the protective layer 3 may be used.

The optical recording medium of the present invention can be recorded by irradiation with a gas laser such as a helium-neon laser (oscillation wavelength: 633 nm), but is preferably a laser having a wavelength of 750 nm or more, particularly a gallium-aluminum-arsenic semiconductor laser. A method of recording by irradiation with a laser beam having an oscillation wavelength in the near-infrared or infrared region such as (oscillation wavelength 830 nm) is suitable. For reading, the aforementioned laser beam can be used. On this occasion,
Writing and reading can be performed with lasers of the same wavelength, and can also be performed with lasers of different wavelengths.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples, but is not limited thereto.

Example 1 On a polycarbonate (hereinafter abbreviated as PC) substrate provided with a pregroove by injection molding having a diameter of 130 mmφ and a thickness of 1.2 mm, the naphtholactam compound No.
A solution obtained by dissolving 3 parts by weight of the naphtholactam compound of (1) in 97 parts by weight of diacetone alcohol was applied by a spinner coating method, and then dried to obtain an organic thin film recording layer of 800 °.

The optical recording medium prepared in this manner is mounted on a turntable, and the turntable is rotated at 1800 rpm by a motor, and a semiconductor laser having an oscillation wavelength of 830 nm is used. Information was written at 8 nW at a recording frequency of 3 MHz, reproduced at a read power of 0.8 mW, and the reproduced waveform was analyzed for spectrum (scanning filter, bandwidth 30 KHz) to measure the C / N ratio.

Next, the same recording medium, the recorded portion in said measurement condition was measured C / N ratio after reading repeated 10 ⁵ times.

Further, the same recording medium produced under the above conditions was 65 ° C.
After being left for 2,000 hours under the condition of 85% RH, the transmittance (measured at 830 nm) and the C / N ratio after the environmental storage stability test were measured. Table 1 shows the results.

Examples 2 to 9 Naphtholactam compound No. (1) used in Example 1
No. (4), (11), (14), (18), (2
2), (27), (30) and (37) were replaced by recording media in the same manner as in Example 1 to produce optical recording media of Examples 2 to 9, respectively.

The optical recording media of Examples 2 to 9 were measured in the same manner as in Example 1. Table 2 shows the results.

Examples 10 and 11 The following compound Nos. (41) and (42) and the naphtholactam-based compound No. (2) were mixed with diacetone alcohol at a weight ratio of 1: 2, respectively. Then, an organic thin film recording layer having a dry film thickness of 850 mm was provided to produce optical recording media of Examples 10 and 11, respectively.

The optical recording media of Examples 10 and 11 thus produced were measured in the same manner as in Example 1. Table 3 shows the results.

Comparative Example 1 Except for removing Compound No. (2) used in Example 10,
An optical recording medium was manufactured in the same manner as in Example 10, and the measurement was performed in the same manner. Table 3 also shows the results.

Example 12 2 parts by weight of compound No. (7) and a nitrocellulose resin (Ohales Lacquer, Daicel Chemical Co., Ltd.)
A solution prepared by mixing 1 part by weight of diacetone alcohol with 97 parts by weight of diacetone alcohol by a spinner coating method and having a pre-groove formed by injection and having a diameter of 130 mmφ and a thickness of 1.2 mm.
It was applied on a PC substrate to obtain an organic thin film recording layer having a dry film thickness of 1000 mm.

The optical recording medium thus prepared was measured in the same manner as in Example 1. Table 4 shows the results.

Examples 13 to 15 Compound No. (7) used in Example 12 was replaced with Compound No.
Instead of (10), (21) and (32), recording media were produced in the same manner as in Example 12, and optical recording media of Examples 13 to 15 were produced.

The optical recording media of Examples 13 and 14 were measured in the same manner as in Example 1. Table 4 shows the results.

Example 16 A pregroove was provided on a 0.4 mm-thick PC substrate having a wallet size by a hot press method, and 3 parts by weight of the naphtholactam-based compound No. (8) was mixed with 97 parts by weight of diacetone alcohol on the pregroove. The solution was applied by a bar coating method, and dried to obtain an organic thin film recording layer having a thickness of 1000 °. Further, a PC substrate having a wallet size of 0.3 mm and a thickness of 0.3 mm were adhered thereon by a hot roll method via an ethylene-vinyl acetate dry film to produce an optical recording medium having an adhered structure.

The optical recording medium produced in this manner was mounted on a stage driven in the X and Y directions, and a spot size of 3.0 mm was applied to the organic thin film recording layer from a 0.4 mm thick PC substrate side using a semiconductor laser having an oscillation wavelength of 830 nm. Write information in the Y-axis direction with a recording pulse of 50 msec at a recording power of 3.5 mW with a recording power of 3.5 mW, and reproduce with a reading power of 0.3 mW, and the contrast ratio B = signal intensity of the recording section).

Further, the same recording medium manufactured under the above conditions was used in Example 1.
An environmental preservation stability test was performed under the same conditions as described above, and then the transmittance and contrast ratio were measured. Table 5 shows the results.

Examples 17 to 20 Two kinds of the naphtholactam compounds were mixed with diacetone alcohol at a weight ratio of 1: 1 in each of the combinations shown in Table 6, and applied in the same manner as in Example 1 to obtain a dry film thickness of 850.
The organic thin-film recording layers of Å were provided, and optical recording media of Examples 17 to 20, respectively, were produced.

The optical recording media of Examples 17 to 20 thus prepared were measured in the same manner as in Example 1. Table 6 shows the results.

[Effects of the Invention] As described above, according to the optical recording medium of the present invention,
It has absorption on the long wavelength side, enables recording with high sensitivity even using a long wavelength oscillation laser such as a semiconductor laser, and provides a high C / N ratio by forming a good pit shape.

Further, it is possible to provide an optical recording medium which can be manufactured by a coating method, has good stability to heat, has excellent storage stability, and has little reproduction deterioration.

[Brief description of the drawings]

1 to 4 are cross-sectional views each showing an embodiment of the optical recording medium of the present invention. DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Recording layer 3 ... Protective layer 4 ... Undercoat layer

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-124988 (JP, A) JP-A-62-132681 (JP, A) JP-A-62-216792 (JP, A) JP-A 62-124792 216793 (JP, A) JP-A-62-230857 (JP, A) JP-A-63-77973 (JP, A) JP-A-1-165669 (JP, A) JP-A-2-190390 (JP, A) JP-A-2-248287 (JP, A)

Claims (1)

(57) [Claims] (1) The following general formulas (I), [II], [III] and [I
Naphthalactam compound represented by V] or [V]
Having one or more recording layers.
Optical recording medium. (However, in the general formulas [I] to [V], R₁Is a replacement
Or unsubstituted alkyl, cycloalkyl, alkoxy
Represents a di, allyl, aryl or aralkyl group
Then R_TwoAnd R_ThreeIs a hydrogen atom, a halogen atom or a monovalent
Represents an organic residue, R_Four~ R₁₂Is hydrogen atom, halogen atom
Or a monovalent organic residue. R₁₃And R₁₄Also replace
Or an unsubstituted alkyl group, substituted or unsubstituted ant
Or substituted or unsubstituted styryl groups or substituted
Or an unsubstituted heterocyclic group. Y is replaced or not
Divalent hydrocarbon group forming a substituted 5- or 6-membered ring
Is shown. m is 1, 2 or 3, p is 0, 1 or 2, q is 0.1
Or 2, r is 1 or 2, l is an integer of 1 or 2.
You. X Represents an anion residue. )