JPH02167271A - Naphthoquinone derivative and optical recording medium using the derivative - Google Patents

Abstract

NEW MATERIAL:A naphthoquinone derivative of formula I [R<1>, R<2> are H, alkyl which may be substituted, cycloalkyl which may be substituted, aryl which may be substituted, alkenyl which may be substituted; R<3> is H, halogen, alkyl, acylamino, alkoxy; R<4> is H, halogen; X is S, Se; Y is CH, N]. EXAMPLE:The compound of formula II. USE:A dye for optical recording medium. It is readily vacuum-evaporable, highly compatible to organic solvent and coatable, too. Moreover, it has high reflectance to make good contrast with high storability. The optical recording medium can be readily and efficiently prepared and has excellent characteristics such as recording and regeneration and high stability. PREPARATION:For example, the reaction of a compound of formula III with 2-aminobenzenethiol is conducted in alcohol in the presence of hydrochloric acid to give the compound of formula II.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel naphthoquinone derivative and an optical recording medium using the derivative.

[Conventional technology]

2. Description of the Related Art Various configurations are conventionally known as optical recording media in which recording is performed by utilizing changes in the state of materials caused by light energy at the oscillation wavelength of a semiconductor laser.

For example, Tokukai Akira! ;! ;-970JJ publication, gJ
In J'lda publication, phenalene dyes were used in JP-A No. 1g-
Japanese Patent No. 2217793 discloses a recording layer in which a naphthoquinone dye is provided.

[Problem to be solved by the invention]

Among the conventional optical recording media mentioned above, JP-A-Sho SS-? 70
In the method using the phthalocyanine dye disclosed in J. No. 3, the phthalocyanine dye has problems such as low sensitivity, high decomposition point, and difficulty in vapor deposition, and furthermore, it has extremely high solubility in organic solvents. It also has the problem that it is difficult to apply when used for coating by application.

On the other hand, JP-A Showa SG-ZA JJQ-da issue has the same SG-point. If the reflectance is low, the contrast related to the reflectance between the portion recorded by the laser beam and the unrecorded portion will be low, making it difficult to reproduce the recorded information. Additionally, organic dyes generally have a problem of poor storage stability.

[Means to solve the problem]

The present invention provides novel naphthoquinone derivatives that are easy to vapor deposit, have high solubility in organic solvents, can be coated by coating, and have high reflectance, good contrast, and excellent storage stability. The purpose of the present invention is to provide an optical recording medium using
It represents a substituted or unsubstituted aryl group or a substituted or unsubstituted alkenyl group, R3 represents a hydrogen atom, a halogen atom, an alkyl group, an acylamino group, or an alkoxy group, K represents a hydrogen atom, a halogen atom, and X represents S or S
e, and Y represents CH or N. ), and an optical recording medium characterized by being provided with a recording layer containing the above derivative.

The present invention will be explained in detail below.

2) The naphthoquinone derivative represented by the general formula [I] of the present invention is preferably the following formula [■], Cm
) or [IV].

(In the formula, R' and R2 represent a hydrogen atom, a substituted or unsubstituted alkyl group, a cycloalkyl group, an aryl group, or an allyl group, and R3 represents a hydrogen atom, a halogen atom, an alkyl group, an acylamino group, or an alkoxy group. (In the formula, R' and R2 represent a hydrogen atom, a substituted or unsubstituted or unsubstituted alkyl group, cycloalkyl group, aryl group, or allyl group, and Rs represents a hydrogen atom, a halogen atom, an alkyl group, or an acylamino group. (In the formula, R1 and R2 represent a hydrogen atom, a substituted or unsubstituted alkyl group, a cycloalkyl group, an aryl group, or an allyl group, and R3 represents a hydrogen atom, a halogen atom, or an alkyl group.) , represents an acylamino group or an alkoxy group.) Examples of the alkyl group represented by R1 and R2 include a methyl group,
Examples of alkenyl groups include phenyl and naphthyl groups, and examples of alkenyl groups include vinyl groups, allyl groups, propenyl groups, butenyl groups, etc. Examples include alkenyl groups.

The halogen atom represented by R3 is CI, F, 1,
Examples of the alkyl group include an alkyl group having a carbon number of /-A, and examples of the azila group include acyl groups having an acyl group of a carbon number of /-A, such as formyl, acetylpropionyl, and butyryl. Examples of the alkoxy group include an alkoxy group having a carbon number of -4.

3 represented by R1 and R2 in the above-mentioned formula (I)
Examples include an alkoxy group, an alkoxyalkoxy group, an alkoxyalkoxyalkoxy group, an allyloxy group, an aryl group, an aryloxy group, a cyano group, an alkoxycarbonyl group, a hydroxy group, a tetrahydrofuryl group, and a halogen atom.

Examples of substituents or substituent atoms of cycloalkyl groups, aryl groups, or alkenyl groups include alkyl groups, alkoxy groups, alkoxyalkoxy groups, alkoxyalkoxyalcokyne groups, allyloxy groups, aryl groups, aryloxy groups, cyano groups, and alkoxycarbonyl groups. base,
Examples include a hydroxy group, a tetrahydrofuryl group, and a halogen atom.

It has a naphthoquinone color represented by formula (I) above and has a molecular absorption coefficient of 10' to 105C! n″″1.

Next, an optical recording medium of the present invention using such a novel naphthoquinone compound of the present invention will be explained.

The optical recording medium of the present invention basically consists of a substrate and a recording layer, but if necessary, an undercoat layer may be provided on the substrate or a protective layer may be provided on the recording layer. Can be done.

The substrate used in the present invention may be transparent or opaque to the laser beam used. Examples of the substrate material include supports for numerical recording materials such as glass, plastic, paper, plate-shaped or foil-shaped metals, and among these, plastics are preferred from various points of view. . Plastics include acrylic resin, methacrylic resin,
Vinyl acetate resin, vinyl chloride resin, nitrocellulose,
Examples include polyethylene resin, polypropylene/resin, polycarbonate resin, polyimide resin, polysulfone resin, and the like.

When using the compound of formula CI) as the recording layer in the optical recording medium of the present invention, the film thickness is 100=! rA
m, preferably 1000″A to 3 μm.

As a film forming method, commonly used thin film forming methods such as a vacuum evaporation method, a sputtering method, a doctor blade method, a casting method, a spinner method, and a dipping method can be employed.

When forming a film, a binder can also be used as necessary. As the binder, known binders such as PVAVPVP, nitrocellulose, cellulose acetate, polyvinyl butyral, and polycarbonate are used, and the amount of the compound of the general formula [■] to these binder resins is 0.0/or more in weight ratio. This is desirable.

In addition, transition metal chelate compounds (e.g., acetylacetonate chelate, bisphenyldithiol, salicylaldehyde oxime, bisdithio-α-
diketone, etc.) may be included. Furthermore, the dye represented by the general formula [I] used in the present invention may be used alone, or two types having different substituents may be used in combination. Furthermore, other dyes can be used in combination if necessary. Other pigments may be other types of compounds of the same type, or pigments from other systems such as triarylmethane dyes, azo dyes, cyanine dyes, squalirium dyes, etc. Doctor blade method, casting method, spinner When forming a recording layer by a coating method such as coating method, dipping method, especially spinner method, coating solvents include bromoform, dibromoethane, tetrachloroethane, ethyl cellosolve, xylene, chlorobenzene, cyclohexanone, etc. with boiling point/20
~/rO°C is preferably used.

In addition, in the case of film formation by the spinner method, the rotation speed is so~
! r 000 rpm is preferred and after the spin code,
Depending on the case, treatment such as heating or exposure to solvent vapor may be performed.

The recording layer of the optical recording medium of the present invention may be provided on both sides of the substrate or only on one side.

] Recording on the recording medium obtained as described above is usually carried out using a laser beam, preferably a semiconductor laser beam, focused to about 1μ nail length on the recording layer provided on both sides or one side of the substrate. I'll do it by guessing.

In the portion irradiated with the laser beam, thermal deformation of the recording layer such as decomposition, evaporation, and melting occurs due to absorption of laser energy.

The recorded information is reproduced by using a laser beam and reading the difference in reflectance between the areas where thermal deformation has occurred and the areas where no thermal deformation has occurred.

As the laser beam used for recording on or reproducing from the optical recording medium of the present invention, a semiconductor laser is preferable from the viewpoints of light weight, ease of handling, compactness, and the like.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples as long as they do not exceed the gist thereof.

Example/Synthesis A compound represented by the following structural formula, 2.729, and co-aminobenzenethiol/, 2 j t f were reacted in a mixed solvent of 100 at of ethanol and aoml of aqueous ly% HCl for 72 hours under stirring under room conditions. I let it happen.

It was neutralized with an io% NaOH aqueous solution to obtain a nandoquinone derivative represented by the following structural formula @.

Purification was performed three times using a silica gel column (benzene: ethyl acetate = danyl) to obtain a purified product.

As shown in FIG. 1, the λmaxlti of the crystal glue b in the roform solution was 7A nm.

Molecular extinction coefficient (ε): 2. J X 10' λmax in chloroform solution: 2 nm mass spectrum: ? ? (M+) Film formation method Naphthoquinone dye obtained as above/? was dissolved in tetrachloroethane j09 and filtered through a 0.22μ filter to obtain a solution. Add Jml of this solution to a depth of 7
00A, methyl methacrylate resin substrate with grooves (groups) made of ultraviolet curing resin with a width of 0.7μ (/,
20 ㎋〆) and drop it on top of the pso using a spinner method.

The coating was applied at a rotation speed of rpm and dried at 40° C. for 10 minutes.

It was applied to a glass plate under the same conditions and the coating film thickness was measured by Talystep, and it was found to be 700 mm. As shown in Figure 2, the maximum absorption wavelength of the coating film is 790 nm.
The reflectance was 29% (g30 nm), and the shape of the spectrum was broad.

Optical Recording Method When this coating film was irradiated with a semiconductor laser beam having a center wavelength of 790 nm and a beam diameter of 1 μm, extremely clear pits with a width of about 1 μm and a pit length of about λμ were formed.

C/N ratio in dynamic characteristic evaluation! It had high r2dB (gmW) and good storage stability (60°C, tro%RH).

Example 1 A film was formed in the same manner as in Example 1, except that the compound shown in Table 1 below was used in place of the compound represented by the structural formula (1). A thin film substrate with maximum absorption wavelength was obtained.

When writing was performed on the thin film thus obtained using a semiconductor laser as a light source, pits with a uniform and clear shape were obtained, and the C/N ratio was also good.
Storage stability was also good.

Example J Toquinone dye f2×10”Tor with the following structural formula
Under a vacuum of r, heat to about g o − / j O ℃, and methacrylic resin (hereinafter referred to as PMMA) of the plate thickness/column is heated.
Vacuum deposited onto the substrate. The thickness of the deposited film was 1g00A as a result of measuring the thickness of the vacuum deposited film using a crystal vibration type film thickness meter. The maximum absorption wavelength measured by the spectrophotometer was 790 nm, and the shape of the spectrum was broad.

Naphthoquinone dye: This recording medium also exhibited good storage stability under room light, temperature of 90° C., and humidity of 0.

Example D When the compounds shown in Table 1 below were used in place of the naphthoquinone dye used in Example J and deposited on a substrate, a thin film substrate having the maximum absorption wavelength shown in Table 2 below was obtained. . When writing was performed on the thin film thus obtained using a semiconductor laser as a light source, bits with a uniform and clear shape were obtained. The C/N ratio is also good.
Storage stability was also good.

When writing was performed on the thin film obtained in this way using a semiconductor laser as a light source with a beam diameter of 1 μm and a wavelength of 7 nm, uniform and clearly shaped bits (holes) were formed.
was gotten. Carrier level/noise level (C/N
) ratio was also high and good.

Example S Synthesis Purification and isolation were carried out using the following structural formula (% formula %:) to obtain a naphthoquinone derivative represented by the following structural formula. (Yield 9) (iso)H7QNH0 Compound group (O,/5mm01) and the following structural formula SOo (0.2r mmol) were degassed with N,N
The solution was dissolved in 7 ml of -dimethylformamide and stirred at room temperature for 6 to 72 hours under an argon atmosphere.

After the reaction was completed, the reaction solution was poured into ioomt water, and the precipitate was collected by e-filtration.

Next, this product was dissolved in a mixed solvent of ethanol boml and 6N hydrochloric acid, and stirred for 6 to 12 hours. After neutralization with an aqueous sodium acetate solution, extraction with chloroform was performed, the solvent was eluted under reduced pressure, and the reaction mixture was subjected to silica gel column chromatography C387 (ISO). λmax (CHCl, ) 7!; At 2 nm, ε was /, O×704.

Example 6 When synthesized in the same manner as Example S, λ1n shown in Table 3 was obtained.
A naphthoquinone derivative with a melting point of aX % ε was obtained.

Example Synthesis Synthesis Example/Co-aminobenzenethiol/, 2J
? Instead, a naphthoquinone derivative represented by the following structural formula was obtained in the same manner as in Example/, except that u used a compound represented by the following structural formula /, and j'j-5'.

The melting point of this compound is /'Ig~iso℃, and λma
x (Cl-lCl!) is 773 as shown in Figure 3.
nrn and t=2. /X10'.

Film Forming Method The naphthoquinone derivative obtained in the above synthesis example was applied onto a methino(methacrylate) resin substrate by a spinner method according to the method described in Example 1.

The maximum absorption wavelength of the coating film is 7 g? The shape of the spectrum was wide in nm.

Optical Recording Method When the above coating film was irradiated with a semiconductor laser beam having a center wavelength of 7 g Onm, a bit with a clear outline was formed.

The storage stability (bo℃, go%RH) of this coating film was relatively good.Examples: Compounds shown in Table 9 were used instead of the compounds used in the examples. Upon coating, a thin film substrate having the maximum absorption wavelength shown in Table 9 was obtained. When writing was performed on the thin film thus obtained using a semiconductor laser as a light source, bits with a uniform and clear shape were obtained.

The C/N ratio was also good, and the storage stability was also good.0 [Effects of the Invention] As detailed above, the naphthoquinone derivative of the present invention has
It is easy to vapor deposit, has high solubility in organic solvents, can be coated by coating, and has high reflectance, good contrast, and excellent storage stability.

Therefore, the optical recording medium of the present invention provided with a recording layer containing such a derivative can be manufactured easily and efficiently, has excellent recording and reproduction characteristics, and is highly stable. It is extremely useful industrially.

[Brief explanation of the drawing]

FIG. 1 is an absorption spectrum diagram of the compound obtained in Example/in a chloroform solution. In the figure, the vertical axis represents absorbance, and the horizontal axis represents wavelength (nm). FIG. 2 is an absorption and reflection spectrum chart of the coating film obtained in Example. In the figure, the solid line represents the absorption spectrum, and the broken line represents the reflection spectrum. The left vertical axis represents absorbance, and the right side represents reflectance (ri). The horizontal axis represents wavelength (nrn). FIG. 3 is a spectrum diagram of the compound obtained in Example 7 in a chloroform solution. In the figure, the vertical axis represents absorbance, and the horizontal axis represents wavelength (nm, l'). Applicant: Mitsubishi Chemical Industries, Ltd. Agent: Yo Hase - (and 7 others) Dan Issho 1 2 people T( (nrn)

Claims (2)

[Claims] (1) The following general formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
I] (In the formula, R^1 and R^2 represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkenyl group) , R^3 represents a hydrogen atom, a halogen atom, an alkyl group, an acylamino group, or an alkoxy group, R^4 represents a hydrogen atom, a halogen atom, and X
represents S or Se, and Y represents CH or N. ) naphthoquinone derivatives. (2) Recording is performed by irradiating a recording layer containing a dye supported on a substrate with a focused laser beam that causes a thermal change in the dye to cause a partial change in the recording layer, and then performing the recording. An optical recording medium in which reproduction is performed by selecting a portion, characterized in that a naphthoquinone derivative represented by the general formula [I] is used as the dye.