JPH01176585A - Optical recording medium - Google Patents

Abstract

PURPOSE:To furnish an optical recording medium which has a practically excellent characteristic and is economically profitable, by a method wherein a recording layer containing a specific phthalocyanine compound is established on a transparent substrate. CONSTITUTION:An organic thin film layer containing at least one kind of a phthalocyanine compound given by the formula (I) is established on a substrate. In the formula, rings A1-A4 represent a benzene ring, a naphthalene ring, or an anthracene ring which may respectively have independently a substituent. M represents a hydrogen atom, or a metallic atom which may have a halogen atom and an oxygen atom, or a metallic atom which may have OR13, OSiR14R15 R16. X1 to X4 represent respectively independently -NH-, or -O-, or -S-. R1 to R12 represent respectively independently a hydrogen atom or an aliphatic hydrocarbon group, an aromatic hydrocarbon group or an aromatic heterocyclic group, or -OR17. Though k, l, m and n represent respectively independently an integer of 0 to 4, all of them do not simultaneously represent zero.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an optical recording medium on which additional recording can be performed using a focused beam of a semiconductor laser. external memory.

The present invention relates to optical recording media used to record various types of information such as images and audio.

(Conventional technology) The above-mentioned recordable optical recording medium is tellurium.

Recording media having inorganic recording layers made of thin films of low-melting metals such as tellurium alloys and bismuth alloys are beginning to be put into practical use. However, these recording media have low productivity because they use thin film formats in vacuum, such as vacuum evaporation and sputtering.Furthermore, the recording layer has a high thermal conductivity, which limits the recording density. Since toxic substances are used, hygiene is a problem.

In order to solve these problems, in recent years, methods of using organic dyes as recording media have been studied.
A recording medium with a recording layer made of an organic dye that absorbs in the semiconductor laser oscillation wavelength region, such as naphthoquinone (Japanese Patent Application Laid-open No. 112793/1983), phthalocyanine dye (US Pat. No. 4,298,975), and naphthalocyanine dye (US Pat. No. 4,492,750). Proposed. However, in the recording media using organic dyes that have been proposed so far,
durability.

In terms of reflectance, they have disadvantages in that sufficient characteristics cannot be obtained, their solubility in solvents is poor, and thin film formation methods using economically advantageous coating methods cannot be applied.

(Means for Solving the Problems) The present inventors have found that it is possible to improve the problems of recording media using organic dyes. An advantageous optical recording medium has now been invented.

That is, 1 the present invention provides an information recording medium that performs recording by causing a state change by irradiation with high-density energy such as a laser beam.
This is an optical recording medium having a recording layer containing a phthalocyanine compound represented by:

General formula [■] In the formula, the rings A I'' A < each independently represent a benzene ring, a naphthalene ring, or an anthracene ring which may have a substituent.

M is a hydrogen atom, a halogen atom, a metal atom which may have an oxygen atom, or (○R13)I), (○
S i R+a R+s R+6) Represents a metal atom that may have q.

(Here, RI3. Rla, R+s+ Rib
Each independently represents a hydrogen atom, a W-substituted or unsubstituted aliphatic hydrocarbon group.

It represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group, and p and q represent integers of 0 to 2. ) Xl to X4 are each independently -NH-, or -〇-
Represents 1 or -8-.

R1 to R12 each independently represent a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or -OR+7 .

(Here, R1? represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a silyl group.) k, β2m and n each independently represent an integer from 0 to 4, but they cannot all be 0 at the same time.

To further explain the substituents in detail, R1 to R1
2 each independently represents an aromatic hydrocarbon group, an aliphatic hydrocarbon group, or an aromatic heterocyclic group; 1, for example, a phenyl group, a naphthyl group, an anthryl group, a methyl group;

Ethyl group, propyl group, pentyl group, hexyl group.

Substituents include octyl group, stearyl group, pyridyl group, carbazolyl group, dibenzofuryl group, benzothiazolyl group, etc., but are not limited to these substituents.

In addition, these groups include a hydroxyl group, an alkyl group, a halogen atom, an amino group, an alkylamino group, a dialkylamino group, an alkoxy group, a nitro group, a cyano group, an aralkyl group,
It may have a substituent such as an aryl group, but these substituents are not limited.

M is G1. Na, Li, Cu, Fe, Co, Ni.

Zn, Mn, Pb, Si, Mg, Af-CL In
-Cl, Ti=O, V-0, or (OR+1)I).

(O3i R+aR+sR+J Represents a metal atom that may have Q; where Rl 3 R+ a R1s R
+ b each independently represents a hydrogen atom or a group similar to R1 in general formula (1), and p and q represent an integer of 0 to 2. K,! .

m and n each independently represent an integer from 0 to 4, but they cannot all be 0 at the same time. Moreover, it is preferably an integer of 1 or 2.

The phthalocyanine compound represented by the above general formula is.

It has large absorption in the visible to near-infrared region, making it suitable for recording and reproducing using laser beams.

In the phthalocyanine compound represented by the above general formula [I] used in the present invention, m- is one or more of the following general formula (If) and various metal salts (metal-free phthalocyanine compounds). (if not used) and can be prepared by heating, preferably in an organic solvent. In addition, the nitriles represented by the following general formula (n) have an alkyl group as another substituent.

halogenated alkyl group, alkoxy group, phenoxy group,
A nitro group, an amino group, an alkylamino group, a halogen atom, etc. may be present.

General formula (It) In the formula, X'' represents -NH-, -〇- or -8-, and R
'1 to R/3 each independently represent R in general formula (1),
˜Represents a group similar to R1□. Also, J is the general formula (j
), represents β, m, and n.

Moreover, the phthalocyanine compound of General 2 (1) can be produced using phthalic acids or phthalimides as a starting material.

Alcohols, glycols, xylene, quinoline, α-chlornaphthalene, nitrohenzene, and sulfolane are used in the production of these phthalocyanine compounds.

A general organic solvent such as N,N-dimethylformamide can be used, but it can also be obtained without a solvent.

Further, it may be preferable to use an alkali or an organic amine such as diazabicycloundecene (DBU) or cyclohexylamine as a catalyst.

Furthermore, various metal salts can be used as the raw material metal salts.

The transparent substrate used in the present invention preferably has a transmittance of light for writing and reading signals of preferably 85% or more and has small optical anisotropy. For example, glass, or thermoplastic resins such as chill resin, polycarbonate resin, polyester resin, polyamide resin, vinyl chloride resin, polyvinyl ester resin, polystyrene resin, polyolefin resin (poly-4-methylpentene, etc.), polyether sulfone resin, etc. Examples include substrates using thermosetting resins such as epoxy resins, allyl resins, etc. Among these, the above-mentioned thermoplastic resins are preferred from the viewpoint of ease of molding and ease of providing guide grooves, address signals, etc., and acrylic resins and polycarbonate resins are particularly preferred from the viewpoint of optical properties and mechanical properties.

In the present invention, the thickness of these transparent substrates is .

There is no particular restriction, and it may be in the form of a plate or a film. Also,
Its shape may be five circles or a card shape, and its size is not particularly limited.

Further, the transparent substrate of the present invention usually has guide grooves for position control during recording and reading, and unevenness for preformants such as address signals and various marks. It is preferable to apply it using a stamper or the like when molding (injection, compression, etc.) such a thermoplastic resin.

In the optical recording medium of the present invention, a recording layer containing a phthalocyanine compound can be fixed on a transparent substrate by methods such as vacuum evaporation, sputtering, ion plate method, and LB method (Langmuir-Blodgett method). However, since these methods require complicated operations and are inferior in productivity, so-called coating methods are most preferred. When forming a recording layer by a coating method, alcohols, ketones, and amides are used as phthalocyanine compounds.

It is applied by dispersing or dissolving it in common organic solvents such as sulfoxides, ethers, esters, aliphatic halogenated hydrocarbons, and aromatic hydrocarbons. On this occasion.

When the phthalocyanine compound has an amino group, by forming a salt with an organic acid.

Acetic acid in the above organic solvents to increase solubility.

A mixture of organic acids such as propionic acid, butyric acid, oleic acid and stearic acid can also be used. Also.

At this time, depending on the case, a polymer binder may be added. As the polymer binder, vinyl chloride resin,
Acrylic acid resin, polyester resin, polyethylene resin, polyamide resin, polycarbonate resin, epoxy resin, meccrylic acid resin, vinyl acetate resin, nitrocellulose, polypropylene resin, polyethylene terephthalate resin, phenolic resin or their copolymers, etc. can give. In this case, the ratio of the resin to the phthalocyanine compound is preferably 10 wt% or less.

It is also possible to use the phthalocyanine compound of the present invention by mixing and dispersing or mixing and dissolving other dyes.

Examples of dyes that can be used in combination include already known aromatic or unsaturated aliphatic diamine metal complexes, aromatic or unsaturated aliphatic dithiol metal complexes, phthalocyanine complexes, naphthalocyanine complexes, and squalium dyes. , naphthoquinone complexes, anthraquinone dyes, and polymethine dyes.

The recording layer containing a phthalocyanine compound formed on a transparent substrate has a thickness of 10 μm or less, and preferably has a thickness of 500 μm or less.
It is μm. In addition, by exposing the thin film to the vapor of an organic solvent such as chloroform, tetrahydrofuran, or toluene after coating, the absorption wavelength of the thin film shifts to longer wavelengths, and the sensitivity to light in the oscillation wavelength range of semiconductor lasers can be significantly improved. There is also.

In addition, in order to protect these recording layers, Aβ2031
A protective layer may be provided by depositing an inorganic compound such as 3 ioZ, sio, or SnO. Also as a protective layer.

A polymer may also be applied.

Recording on the recording medium obtained as described above is carried out by irradiating the recording layer provided on the substrate with laser light, preferably semiconductor laser light, focused to about 1 μm.

The area irradiated with the laser beam can be determined by reading the difference in reflectance between the area where the recording layer has experienced a thermal state change such as decomposition, evaporation, or melting due to absorption of laser energy, and the area where the change has not occurred. Let's do it.

As the light source, various lasers such as a He--Ne laser, an Ar laser, and a semiconductor laser can be used, but semiconductor lasers are particularly preferred in terms of cost and size.

As a semiconductor laser, the center wavelength is 830 parts m, 7
Lasers with wavelengths of 80 parts m and shorter can be used.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples.

In the example, the middle part is the part by weight.

Synthesis Example 1 4.0 parts of nitrile having the structure of formula (III), 0.75 parts of vanadium trichloride, diazabicycloundecene (DBtJ
) was added to 50 parts of n-amyl alcohol, refluxed for 6 hours, diluted with 500 parts of methanol, the product was divided into portions, washed with methanol and acetone, and compound (a) was
．． I got 8 copies.

Synthesis Example 2 4.5 parts of nitrile having the structure of formula (IV) and 1.2 parts of aluminum chloride were added to 65 parts of quinoline, heated and stirred at 180 to 190°C for 5 hours, and then diluted with 450 parts of methanol.
Wash the product with methanol and acetone.

2.5 parts of compound (b) were obtained.

Synthesis Example 3 In Synthesis Example 1, the nitrile used was replaced with 4.3 parts of a nitrile having the structure of the following formula (V). 1 Synthesis and purification were carried out in the same manner as in Synthesis Example 1, yielding 2.9 parts of compound (C). Ta.

Synthesis Example 4 In Synthesis Example 1, the nitrile used was represented by the following formula (VT)
Synthesis and purification were carried out in the same manner as in Synthesis Example 1 except that 4.5 parts of a nitrile having the structure were used, and the metal salt used was changed to 10.55 parts of -f chloride. 3.1 parts of compound (d) was obtained. .

Synthesis Example 5 In Synthesis Example 2, the nitrile used was changed to 4.2 parts of a nitrile having the structure of the following formula (■). 9 Synthesis and purification were carried out in the same manner as in Synthesis Example 2, and 2.0 parts of compound (e) was obtained. Ta.

(α) C) QCH.

■ 3-...-shi\ Coco Pigo-O c')13 H3C-C-C)-13 H3 CH3 (k) Example 1 Phthalocyanine compound (a) 2 on a Pyrex substrate
．． After dropping a solution consisting of 7 parts of chloroform and 97.3 parts of chloroform, the substrate was rotated at a speed of 120 rpm for 15 seconds.

Next, this substrate was dried at 80° C. for 20 minutes to obtain a recording medium.

The thickness of this recording layer was 800. The maximum absorption wavelength of this thin film was 805 nm, and the reflectance for light at a wavelength of 830 nm was 28%.

Mount this optical recording medium on the turntable.

While rotating the turntable at 180 rpm.

830 nm laser 5 mW focused at 1.0 μm, 8
Recordings were made with irradiation at MHz.

When the surface of the optical recording medium on which this recording was performed was observed using a scanning electron microscope, the formation of clear pits was observed. In addition, this optical recording medium has 830nm, Q, 4n
When W laser light was irradiated and one reflected light was detected, the C/N ratio was 48 dB.

Example 2 Phthalocyanine metal compound (
b) After dropping a solution consisting of 1.9 parts of methyl cellosolve and 98.1 parts of methyl cellosolve, the substrate was
Rotated for 0 seconds.

Next, this substrate was dried at 80° C. for 30 minutes under reduced pressure to obtain a recording medium.

The thickness of this recording layer was 600. The maximum absorption wavelength of this thin film was 790 nm, and the reflectance for light with a wavelength of 830 nm was 28%.

Further, when recording was performed on this recording medium in the same manner as in Example 1, clear focus formation was observed on the surface of the recording layer, and the C/N ratio was 47 dB.

Examples 3 to 13 Phthalocyanine compound (C) on Pyrex substrate
('ff) was coated in the same manner as in Example 1 to obtain a recording medium.

Table 1 shows the maximum absorption wavelength of this thin film, the reflectance for light with a wavelength of 830 nm, and the results of recording and reproducing the same recording and reproduction as in Example 1 on this recording medium.

-28= Table I 3 c 810nm 31% 51dB4
d 780 26 46 5 e 796 32 52 6 t 807 28 49 7 g 778 25 42 8 h 804 29 49 9 i 791 29 48 10 j810 31 46 11 k 806 30 51 [Effect of the invention ] The present invention is as described above. It depends on the composition and chemical.

It is physically stable and can be recorded and reproduced with high sensitivity using laser beams.

Claims (1)

[Claims] 1. An optical recording medium characterized by having an organic thin film layer containing at least one phthalocyanine compound represented by the following general formula [I] on a substrate. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. are included▼ In the formula, rings A_1 to A_4 each independently represent a benzene ring, a naphthalene ring, or an anthracene ring which may have a substituent. M is a hydrogen atom, a halogen atom, a metal atom that may have an oxygen atom, or (OR_1_3)p, (OS
iR_1_4R_1_5R_1_6) represents a metal atom that may have q. (Here, R_1_3, R_1_4, R_1_5, R_1
_6 each independently represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group, p and q are 0 to 2 represents an integer. ) X_1 to X_4 are each independently -NH- or -
Represents O- or -S-. R_1 to R_1_2 each independently represent a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or -OR_1_7. (Here, R_1_7 represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a silyl group.) k , l, m, and n each independently represent an integer from 0 to 4, but they cannot all be 0 at the same time.