JPH01130984A - Optical recording medium - Google Patents

Abstract

PURPOSE:To obtain an optical recording medium with practically superior properties and economic advantage by forming a recording layer containing a specific compound on a transparent substrate. CONSTITUTION:The best method to fix a recording layer containing a phthalocyanine compound as shown by a formula(rings A1-A6represent a benzene ring, a naphthalene ring, an anthracene ring or a nitrogen-contained complex ring independently) is effected by application process. When the recording layer is formed by the application method, a solution obtained by dispersing or dissolving a porphyrazine binuclear compound in ordinary organic solvent such as alcohols, ketones, amines, sulfoxides, ethers, esters, aliphatic halogenated hydrocarbons or aromatic hydrocarbons, is applied. Recording on a recording medium is made by projecting a laser beam condensed in a flux of about 1mum, preferably a semiconductor laser beam on the recording layer. As a result, a chemically and physically stable recording medium with sufficient absorption and a high reflective factor is obtained by a high productivity application method.

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 made intensive studies to improve the problems of recording media using organic dyes, and have found that the recording medium has excellent practical characteristics and is also economically advantageous. This led to the invention of a new optical recording medium.

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

General formula CI) In the formula, rings A and ~A6 each independently represent a benzene ring, a naphthalene ring, an anthracene ring, or IB, mA
, I[B, I[[A, I[[B, IVA, IVB, VA
.

Represents a metal atom belonging to group VB, VIB, ■B, and group ■.

Z and Y each independently represent a halogen atom, an oxygen atom, or a hydroxyl group.

ORIl S RIl S e R1, T e R
(, or -O3i R2R3R4, where R,
is an alkyl group which may have a substituent, an aryl group which may have a substituent, and an acyl group which may have a substituent.

It is a cycloalkyl group that may have a substituent or a polyether that may have a substituent, and R2R3R4 may be the same or different, and each is an alkyl group.

It is an aryl group, a cycloalkyl group, a siloxy group or an alkoxy group.

The substituents X may be the same or different, and each may have a halogen atom, a hydroxyl group, an alkyl group that may have a substituent,
An optionally substituted aryl group, an optionally substituted heterocyclic group, ORa, S Rs.

NHCORs, N=NRs, NR6R7,
-OS i R5RbR), -S O□N R
e Rq, C0NR11R9,CHzNHC
OCHzNReR*.

-GOOR9, -Not, -3O, H or -CN. Here, R5 is the same as R1.

Rh and R'r may be the same or different, and each represents a hydrogen atom, an alkyl group that may have a substituent, a dichlorofurkyl group that may have a substituent, or an aryl group that may have a substituent. Alternatively, Rh and Rq may be taken together to form a 4- to 7-membered heterocycle containing the nitrogen atom. RIl represents a hydrogen atom or an alkyl group. R9 is a hydrogen atom, an alkyl group that may have a substituent, or an aryl group that may have a substituent.

Heterocyclic group which may have a substituent or -R1゜-NRl
It represents lRIg; here, RIG is an alkyl group having 1 to 4 carbon atoms, and RIl and R+□ may be the same or different. Alkyl group or R11 which may each have a substituent separately
+RI2 together represent a heterocycle containing a nitrogen, oxygen or sulfur atom.

p and q are either 0, 1 or 2 and represent the number of substituents Z and Y.

t, j, Il, m, n are each independently O~8
represents an integer and represents the number of substituents X.

The phthalocyanine compound represented by the above maximum (I) used in the present invention is 9, for example, 3 represented by the following formula (II).
, 3'4,4'-tetracyanobiphenyl, an 0-dicyano compound represented by the following maximum (Ill), and a metal or metal compound.
6 is each independently a benzene ring.

Represents a naphthalene ring, anthracene ring, or the nitrogen-containing heterocycle shown below.

The substituents X may be the same or different, and may each independently include a halogen atom, a hydroxyl group, an alkyl group that may have a substituent, an oryl group that may have a substituent, or a W substituent. A heterocyclic group which may have -0R5, -3R,.

NHCORs, N=NR5, NR6R? , -O3
1R5RbR7,5OzNRsRq, C○NR1
1R9, CH2NHCOCHzNRaRq.

COORq, N O2, SOz H or -C
Represents N. Here, R5 is the same as R.

Rh, R? may be the same or different, and each is a hydrogen atom, an alkyl group that may have a substituent, a cycloalkyl group that may have an N substituent, or an aryl group that may have a substituent. , or R6,R? may be taken together to form a 4- to 7-membered heterocycle containing the nitrogen atom.

R8 represents a hydrogen atom or an alkyl group. R1 is a hydrogen atom, an alkyl group which may have a substituent, or an alkyl group which may have a substituent.

A heterocyclic group which may have a substituent or -R1゜-NR1
1RI2; Here, RIG is an alkyl group having 1 to 4 carbon atoms + R111RI2 may be the same or different. Alkyl group or R1 which each may have a substituent separately
1+RI□ together represent a heterocycle containing nitrogen, oxygen or sulfur atoms.

t, j, ll, m, and n each independently represent an integer of 0 to 8, and represent the number of substituents X.

Furthermore, during the synthesis of the phthalocyanine compound of -maximum CI), a phthalocyanine mononuclear compound and a phthalocyanine trinuclear compound or more are obtained as by-products. These can be separated using a silica gel column, but in some cases, better characteristics can be obtained if these by-products are mixed in.

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 alkyl resins, polycarbonate resins, polyester resins, polyamide resins, vinyl chloride resins, polyvinyl ester resins, polystyrene resins, polyolefin resins (poly-4-methylpentene, etc.), and polyethersulfone resins. 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 nine circles or card-like, and its size is not particularly limited.

Further, the transparent substrate of the present invention usually has unevenness for preformatting, such as guide grooves for position control during recording and reading, address signals, and various marks, as described above. Molding (injection,
It is preferable to use a stun bar or the like to apply the powder during compression (compression, etc.).

In the optical recording medium of the present invention, methods such as vacuum evaporation, sputtering, ion plate method, and LB method (Langmuir-Blodgett method) can be used to fix the recording layer containing the phthalocyanine compound on the transparent substrate. 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, the porphyrazine dinuclear compound may be alcohols, ketones, amides, sulfoxides, ethers, or esters.

It is applied by dispersing or dissolving it in a general organic solvent such as aliphatic halogenated hydrocarbons or aromatic hydrocarbons.

At this time, if the phthalocyanine compound has an amino group, by forming a salt with an organic acid,
Due to the increased solubility of the acids in the above organic solvents9.
It is also possible to use a mixture of organic acids such as propionic acid, i# acid, oleic acid, and stearic acid. Further, at this time, a polymer binder may be added depending on the case.

As a polymer binder.

Vinyl chloride resin, acrylic acid resin, polyester resin,
Polyethylene resin, polyamide resin, polycarbonate resin, epoxy resin, methacrylic acid resin.

Examples include vinyl acetate resin, nitrocellulose, polypropylene resin, polyethylene terephthalate resin, phenol resin, and copolymers thereof.

At that time, the ratio of resin to phthalocyanine compound is 1
It is preferably 0 wt% or less.

Further, it is also possible to use the two phthalocyanine compounds 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 the porphyrazine di-nuclear compound formed on the transparent substrate has a thickness of 10 μm or less, preferably 500 layers/2 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, to protect these recording layers, Al220
The protective layer may be provided by depositing an inorganic compound such as 31S ioz, s i O, 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.

This is determined by reading the difference in reflectance between the areas irradiated with the laser beam and the areas where the thermal state of the recording layer has changed, such as decomposition, evaporation, or melting due to absorption of laser energy, and the area where no changes have occurred.

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

As a semiconductor laser, the center wavelength is 830 nm, 7
Lasers with wavelengths of 80 nm 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.

(b) (g) (h) (j) 191 Example 1 Phthalocyanine compound (a) 3 on Pyrex substrate
．． After dropping a solution consisting of 0 parts of dichloroethane and 97.0 parts of dichloroethane, the substrate was rotated at a speed of 120 rpm for 10 seconds.

Next, this substrate was dried at 50° C. for 30 minutes to obtain a recording medium. The thickness of this recording layer was 800.

The maximum absorption wavelength of the thin film is 780 nm and 830 nm
The reflectance for light with a wavelength of was 28%.

Mount this optical recording medium on the turntable.

While rotating the turntable at 180 rpm.

830nm laser beam focused at 1.0μm 8.0m
W.

Recording was performed with irradiation at 8 MHz.

When the surface of the optical recording medium on which this recording was performed was observed using a scanning electron microscope, clear focus was observed.

In addition, when this optical recording medium was irradiated with a laser beam of 830 nm and 0°8 mW and two reflected beams were detected, it was found that C
/N ratio was 40 dB.

Example 2 Phthalocyanine compound (
f) 2.0 parts and 68.0 parts of methyl cellosolve and = 20
- After dropping a solution consisting of 30.0 parts of dichloroethane, the mixture was rotated at 11,000 rpm for 20 seconds. Next, add this board to 5
A recording medium was obtained by drying at 0° C. for 30 minutes.

The thickness of this recording layer was 900.

The maximum absorption wavelength of this recording layer is 810 nIrl, and 8
The reflectance for 30 nm light was 30%.

Further, when recording was performed on this recording medium in the same manner as in Example 1, clear focus was observed on the surface of the recording layer, and C/N
The ratio was 50 dB.

Examples 3 to 12 Phthalocyanine compound (b) on Pyrex substrate
(e) and (g) to (j) were coated in the same manner as in Example 1 to obtain a recording medium.

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

Table 1 3 (b) 775nm 23χ 42dB4
(c) 790 25 44 5 (d) 800 28 48 6 (e) 805 26 46 7 (g) 765 24 41 8 (h) 794 24 43 9 (i) 796 25 46 10 (j) 79B 24 45 [Invention [Effect] The present invention has the above-described structure, and has a chemical effect.

Physically stable and sufficient absorption for semiconductor laser oscillation region1
It has a characteristic that it has a reflectance, and furthermore, a recording medium can be created by a highly productive coating method.

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] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ In the formula, rings A_1 to A_6 are each independently a benzene ring,
Represents a naphthalene ring, anthracene ring, or the nitrogen-containing heterocycle shown below. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲Mathematical formulas, chemical formulas,
There are tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼
▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲Mathematical formulas, chemical formulas,
There are tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼
▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ Mathematical formulas, chemical formulas,
There are tables etc. ▼ M_1 and M_2 are each independently I A of the periodic table,
I B, IIA, IIB, IIIA, IIIB, IVA, IVB, VA
, represents a metal atom belonging to groups VB, VIB, VIIB and VIII. Z and Y each independently represent a halogen atom, an oxygen atom, a hydroxyl group, -OR_1, -SR_1, -SeR_1, -TeR_1
, or -OSiR_2R_3R_4, where R
_1 is an alkyl group, aryl group, acyl group, cycloalkyl group or polyether, R_2R_3R_4
may be the same or different, and each is an alkyl group, aryl group, cycloalkyl group, siloxy group, or alkoxy group.The substituents X may be the same or different, and each has a halogen atom, hydroxyl group, or substituent an optionally substituted alkyl group, an optionally substituted aryl group, an optionally substituted heterocyclic group, -OR_5, -SR_5, -N
HCOR_5, -N=NR_5, -NR_6R_7, -
OSiR_5R_6R_7, -SO_2NR_8R_9
, -CONR_8R_9, -CH_2NHCOCH_2
NR_8R_9, -COOR_9, -NO_2, -SO
Represents _3H or -CN. Here, R_5 is the same as R_1. R_6 and R_7 may be the same or different, and each is a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group, or R_6 and R_7 together form a 4- to 7-membered heterocyclic ring containing the nitrogen atom. It may form a ring. R
_8 represents a hydrogen atom or an alkyl group. R_9 is a hydrogen atom, an alkyl group that may have a substituent,
Aryl group which may have a substituent, heterocyclic group which may have a substituent or -R_1_0-NR_1_1R_1_
2; here, R_1_0 is an alkyl group having 1 to 4 carbon atoms, and R_1_1 and R_1_2 may be the same or different. An alkyl group which may each have a substituent or R_1_1, R_1_2 taken together represents a heterocycle containing nitrogen, oxygen or sulfur atom. p and q are either 0, 1 or 2 and represent the number of substituents Z and Y. i, j, k, l, m, and n each independently represent an integer of 0 to 8, and represent the number of substituents X.