JPH0569673A - Optical data recording medium and production thereof - Google Patents

Abstract

PURPOSE:To provide an optical data recording medium excellent in preservability and recording characteristics. CONSTITUTION:At first, a polycarbonate substrate with a thickness of 1.2mm, an outer diameter of 120mm and an inner diameter of 15mm having spiral pregrooves with a width of 0.5mum and a depth of 160nm formed thereto at a pitch of 1.6mum is formed by injection molding 4,4',4'',4'''-tetra(monohydroxyethylsulfonylamide) phthalocyanine Cu complex is treated with perchloric acid and the obtained salt is dissolved in isoprpyl alcohol and the resulting solution is applied to the polycarbonate substrate by a spin coating method to form a light absorbing layer. Next, a fluoroplastic coating resin is applied to the formed light absorbing layer by a spin coating method to form a reflecting auxiliary layer and an Au film with a thickness of 500nm is formed on the reflecting auxiliary layer by sputtering to form a reflecting layer and an ultraviolet curable resin is applied to the reflecting layer by a spin coating method to form a protective layer which is, in turn, irradiated with UV rays to be cured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording medium having a light absorbing layer containing a perchlorate or a periodate of a phthalocyanine dye and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, in a dye-based write-once type optical disk, in order to optimize recording characteristics and reproduction characteristics, mainly a light absorbing layer material, an indodicarbocyanine dye, a Ni complex and an aminium salt are used. A system to which a light stabilizer such as a nitroso compound has been added has been used. However, since these systems do not have sufficient weather resistance, especially stability to light, improvement thereof is desired. Therefore, a metal complex of a phthalocyanine dye, which has been considered to have excellent light and heat stability for a long time, is regarded as a promising material for the light absorption layer.

Regarding metal complexes of phthalocyanine dyes (including naphthalocyanine dyes; the same applies hereinafter in the present specification), a central metal and a central metal are used in order to improve solvent solubility and spin coatability. Detailed studies have been conducted on changes in properties due to differences in compounds, introduced functional groups, etc., and many patent applications have been filed. However, there have been almost no studies on improvement of easiness of recording formation using phthalocyanine dyes, particularly reduction of recording power.

[0004]

In the case of a dye-based write-once type optical disc, the maximum reflectance (Rtop) after recording needs to be about the same as that of a commercially available ROM type CD, and therefore the optical absorption at the laser wavelength for recording / reproducing The absorption efficiency of the layer, that is, the absorbance cannot be increased more than necessary.

In the case of the conventional indodicarbocyanine-based material, since it is relatively easy to decompose and generate heat, it was possible to record at a minimum absorbance of about 6 to 10 mW, but in the case of the phthalocyanine-based material, it is possible to record light and heat. Since it is stable, it was not possible to record even with a laser beam of about 10 mW at an absorbance similar to that of the indodicarbocyanine system. This was exactly the same for the conventionally known phthalocyanine-based material having improved solvent solubility during spin coating.

[0006]

[Means for Solving the Problems] In order to reduce the recording power of a phthalocyanine-based material, as in the case of an indodicarbocyanine-based material, part or all of the material undergoes heat decomposition at 300 ° C. or lower. Need to do so. As one means for achieving this, it has been found that it is extremely effective to treat a phthalocyanine-based material with perchloric acid or periodic acid to form a salt with these acids, and arrived at the present invention.

As another means for achieving the above object, (a) a phthalocyanine dye or a salt of a phthalocyanine dye of perchloric acid or periodic acid, (b)
_{^{Wherein: R + · XO 4 - (}} R + is an organic cation, X is Cl or I) was found to be a method of adding a halogenated peroxide salts of organic substance represented by is effective.

The addition amount of (b) to (a) is 1 to 300 wt% of R ⁺ .XO ₄ ⁻ based on the amount of the phthalocyanine dye or its perchlorate or periodate. %, Preferably 5 to 100% by weight. If it is less than 1% by weight, the desired effect cannot be obtained,
On the other hand, if it is more than 300% by weight, the dye is diluted and recording becomes impossible. Examples of R ⁺ .XO ₄ ⁻ are tetraethylammonium perchlorate, tetrapropylammonium perchlorate, tetra-n-butylammonium perchlorate, tetraethylammonium periodide, tetrapropylammonium periodide, tetra-n-butylammonium peraodide. Etc., and tetra-n-butylammonium perchlorate is particularly preferable. That is, R ⁺ · XO ₄ ⁻ is
It may be a halogenated peroxide of a nitrogen alkyl compound such as tetraalkylammonium perchlorate as shown above, or like IRG-003 (manufactured by Nippon Kayaku Co., Ltd.),
It may be an aminium compound that stabilizes the dye. Further, a cyanine dye having a methine chain such as indodicarbocyanine perchlorate may be used.

Any resin material can be used for the reflection auxiliary layer as long as it can be spin-coated as a solution, but it is necessary that the condition of complex refractive index n _E ≦ 1.6 is satisfied. In order to make the reflectance higher and the recording power lower, it is more preferable to use a resin having a complex refractive index n _E ≦ 1.5. Materials that can be used for this purpose include polyterpene resin (n _E = 1.38), fluorinated resin (n _E = 1.4), siloxane resin (n _E = 1.41), oligostyrene resin (n _E = 1.59), etc. Although it is excellent in properties and useful, materials other than the above materials may be used as long as they satisfy the above conditions. As a solvent for dissolving these, a commonly used solvent such as a ketone solvent, an alcohol solvent, a keto alcohol solvent, or a cellosolve solvent or a perchlorinated solvent thereof can be used.

That is, one object of the present invention is (1)
An optical information recording medium having a light absorbing layer formed of an organic thin film, wherein the light absorbing layer is made of a perchlorate or a periodate of a phthalocyanine dye. Is to provide.

Here, the phthalocyanine dye is a generic term for a dye compound having a phthalocyanine skeleton represented by the following general formula 1 in the structural formula, and also includes naphthalocyanine. M in the formula represents a central metal, but Cu, Co or Ni is particularly preferable.

[Chemical 1]

Another object of the present invention is (2) wherein the salt of the phthalocyanine dye is a perchlorate of 4,4 ', 4 ", 4"'-tetra (monohydroxyethylsulfonylamide) phthalocyanine copper complex. Another object is to provide the optical information recording medium described in (1) above, which is a periodate.

Still another object of the present invention is (3) an optical information recording medium having a light absorbing layer made of an organic thin film,
The light absorbing layer, (b) perchlorate or periodate of phthalocyanine dyes or phthalocyanine dyes, and (b) _{^{formula: R + · XO 4 - (}} R + is an organic cation, X is Cl or An optical information recording medium comprising a mixture with an organic halogenated peroxide salt represented by I). ..

Still another object of the present invention is (4) the phthalocyanine dye is 4,4 ', 4 ", 4"'-tetra (monohydroxyethylsulfonylamide) phthalocyanine copper complex, and the organic halogen Another object of the present invention is to provide the optical information recording medium according to (3) above, wherein the modified peroxide salt is tetra-n-butylammonium perchlorate or tetra-n-butylammonium periodate.

Still another object of the present invention is (5) a light-absorbing layer made of a dye is provided on a substrate having a light-transmitting property and spiral pregrooves, and a metal film is further formed thereon. In the production of an optical information recording medium comprising a reflection layer formed of, and a protective layer formed of a resin layer further formed thereon, in forming the light absorption layer, a perchlorate or a periodate of a phthalocyanine dye is formed. Another object of the present invention is to provide a method for manufacturing an optical information recording medium, characterized in that the coating liquid consisting of is applied by a spin coating method.

Still another object of the present invention is: (6) The perchlorate or periodate of the phthalocyanine dye is 4,4 ', 4 ", 4""-tetra (monohydroxyethylsulfonylamide). ) It is to provide the production method according to (5) above, which is a perchlorate or a periodate of a phthalocyanine copper complex.

Still another object of the present invention is (7) a light-absorbing layer made of a dye is provided on a substrate having a light-transmitting property and spiral pregrooves, and a metal film is formed on the light-absorbing layer. (A) a phthalocyanine dye or a perchlorate of a phthalocyanine dye, in the formation of the light absorbing layer in the production of an optical information recording medium, which comprises: acid salt or periodic acid salt, and (b) _{^{formula: R + · XO 4 - (}} R
^A method for producing an optical information recording medium, characterized in that a coating liquid comprising a mixture of ⁺ is an organic cation and X is an organic halogenated peroxide salt represented by Cl or I) is applied by spin coating. It is to be.

Still another object of the present invention is: (8) The phthalocyanine dye of (a) above is 4,4 ', 4 ",
4 ″ ′-tetra (monohydroxyethylsulfonylamide) phthalocyanine copper complex, wherein the organic halogenated peroxide salt of (b) above is tetra-n-butylammonium perchlorate or tetra-n-butylammonium periodate. Is to provide a production method according to (7) above.

Still another object of the present invention is (9) a light absorbing layer made of a dye is provided on a substrate having a light-transmitting property and spiral pregrooves, and a complex refraction layer is further provided thereon. The reflection real part n _E has a reflection auxiliary layer made of a low refractive index resin with n _E ≦ 1.6, a reflection layer made of a metal film is further provided thereon, and a protective layer made of a resin layer is further provided thereon. In the production of the optical information recording medium consisting of, in forming the light absorbing layer and the reflection auxiliary layer, a coating solution for forming a light absorbing layer consisting of a perchlorate or periodate of a phthalocyanine dye, and a low refractive index resin. Another object of the present invention is to provide a method for producing an optical information recording medium, characterized in that each of the following coating liquids for forming a reflection auxiliary layer is applied by a spin coating method.

Still another object of the present invention is (10) a light absorbing layer made of a dye is provided on a substrate having a light-transmitting property and spiral pregrooves, and a complex refractive index is further provided thereon. Since the real part n _E is provided with a reflection auxiliary layer made of a low refractive index resin with n _E ≦ 1.6, a reflection layer made of a metal film is further provided thereon, and a protective layer made of a resin layer is further provided thereon. In the method for producing an optical information recording medium, the following steps are taken: (a) a phthalocyanine dye or a perchlorate or periodate of a phthalocyanine dye, and (b) a formula: R ⁺ .XO ₄ ^- (R ⁺ is an organic cation, X is Cl or I) An organic halogenated peroxide salt represented by a mixture thereof, and a coating solution is applied by spin coating. The manufacturing method of It is to be.

Still another object of the present invention is: (11) The phthalocyanine dye of (a) above is 4,4 ', 4 ",
4 ″ ′-tetra (monohydroxyethylsulfonylamide) phthalocyanine copper complex, wherein the organic halogenated peroxide salt of (b) above is tetra-n-butylammonium perchlorate or tetra-n-butylammonium periodate. That is, the optical information recording medium according to (9) above is provided.

Still another object of the present invention is (12) any one of the above (5) to (11), characterized in that the light absorption layer has a decomposition point or exothermic point of 300 ° C. or lower. Another object of the present invention is to provide a method for manufacturing the optical information recording medium.

[0023]

As described above, the phthalocyanine-based dye is used as a salt of perchloric acid or periodate, or an organic halogenated peroxide salt is added to the dye or its perchlorate or periodate. 10mW by adding
With the following relatively low laser power, the laser-irradiated portion can be heated up to about 300 ° C. by absorption of the phthalocyanine dye itself. At this time, this irradiated portion is further heated by the exothermic decomposition of these ClO ₄ ⁻ ions or IO ₄ ⁻ ions, and finally the phthalocyanine in the laser irradiated portion causes exothermic decomposition. This portion can be read out as a recording pit during reproduction.

[0024]

Example 1 Width 0.5 μm, Depth 160 nm, Pitch 1.6 μ
Thickness 1.2 m with spiral pre-groove
A polycarbonate substrate having an outer diameter of 120 mm, an outer diameter of 120 mm, and an inner diameter of 15 mm was molded by an injection molding method.

As the light absorber, 4,4 ', 4 ", 4""
0.4 g of tetra (monohydroxyethylsulfonylamide) phthalocyanine Cu complex treated with perchloric acid to form perchlorate was dissolved in 10 ml of isopropyl alcohol to give a solution.

This solution was spin-coated on the above polycarbonate substrate.

Further, a fluorine-based coating resin (n _E = 1.4) was provided as a reflection auxiliary layer on the dye-coated substrate by a spin coating method, and the Au layer 500 was further formed thereon.
nm is provided by a sputtering method, an ultraviolet curable resin is applied on the Au layer by a spin coating method, and UV light is irradiated,
Cured.

The optical disc manufactured in this manner was EFM-powered at 9 mW by a recorder for optical discs (DDU-1000 manufactured by Pulstec) and a semiconductor laser of 780 nm.
When a signal was recorded and reproduced at 0.5 mW, a good eye pattern was obtained. Moreover, when a 450 kHz signal was recorded by the same machine, the C / N ratio was 50 dB, while
Rtop was 65%.

Further, at this time, the chart of the weight loss and the heat generation degree of the material used for recording was as shown in FIG.

The above copper phthalocyanine perchlorate is synthesized by adding perchloric acid to 4,4 ', 4 ", 4"'-tetra (monohydroxyethylsulfonylamide) phthalocyanine Cu complex in ethyl acetate, After treatment for 3 hours at room temperature, the product was recrystallized in cold water.

The salt after the final washing was stored in a vacuum drier, dried, and then the yield was determined to be used as a sample for binding acid component analysis.

4,4 ', 4 ", 4""obtained by the above method
0.4 g of perchlorate of tetra (monohydroxyethylsulfonylamide) phthalocyanine Cu complex was dissolved in 10 ml of isopropyl alcohol to prepare a spin coating solution.

[0033]

[Embodiment 2] On the same substrate as in Embodiment 1, 4, 4 ',
0.36 g of 4 ″, 4 ″ ″-tetra (monohydroxyethylsulfonylamide) phthalocyanine Cu complex and 0.04 g of tetra-n-butylammonium perchlorate were dissolved in 10 ml of isopropyl alcohol to obtain a solution by spin coating. Applied.

Then, in the same manner as in Example 1, a reflection auxiliary layer, an Au layer and an ultraviolet curable resin layer were provided. When the optical disk thus manufactured was recorded at 9.8 mW and reproduced at 0.5 mW using the same recorder as in Example 1, a good eye pattern was obtained. When a 450 kHz signal was recorded, the C / N ratio was 52 dB. At this time, Rtop was 68%.

The chart of the weight loss and the heat generation amount of the material used for recording at this time is as shown in FIG.

[0036]

Comparative Example On the same substrate as in Examples 1 and 2, 4,4 ′, 4 ″, 4 ″ ″-tetra (monohydroxyethylsulfonylamide) phthalocyanine Cu complex was used as a light absorber in Example 1, It was applied by the spin coating method in the same manner as in 2. Further, a reflection auxiliary layer, an Au layer, and an ultraviolet curable resin layer were provided in the same manner as in Examples 1 and 2. When the optical discs thus produced were recorded at a maximum of 13 mW and reproduced at 0.5 mW using the same recorder as in Examples 1 and 2, no reproduced waveform was obtained and there was no recorded trace. It was

The temperature vs. mass loss and calorific value charts of the materials used for recording at this time are shown in FIG.

[0038]

The optical information recording medium of the present invention has both excellent storability and excellent recording characteristics, and has extremely improved reliability as compared with the conventional optical information recording medium. Since the optical information recording medium of the present invention can record at 10 mW or less, it can be easily recorded by a relatively inexpensive and commercially available recorder using a semiconductor laser.

[Brief description of drawings]

FIG. 1 is a chart of temperature versus mass loss and heat generation amount of a photosensitive material in an example of the optical information recording medium of the present invention.

FIG. 2 is a chart of temperature vs. mass loss and heat generation amount of a photosensitive material in another example of the optical information recording medium of the present invention.

FIG. 3 is a chart of temperature vs. mass loss and heat generation amount of a photosensitive material in a conventional optical information recording medium.

Claims (4)

[Claims] 1. An optical information recording medium having a light absorbing layer made of an organic thin film, wherein the light absorbing layer is made of a perchlorate or a periodate of a phthalocyanine dye. Optical information recording medium. 2. A light-absorbing layer made of a dye is provided on a substrate having a light-transmitting property and pregrooves formed in a spiral shape, and a reflective layer made of a metal film is further provided thereon, and further thereon. In the production of an optical information recording medium comprising a protective layer comprising a resin layer, a coating solution comprising a phthalocyanine dye perchlorate or periodate is applied by spin coating when forming the light absorbing layer. A method for manufacturing an optical information recording medium, comprising: 3. A light-absorbing layer made of a dye is provided on a substrate having a light-transmitting property and pregrooves formed in a spiral shape, and a reflective layer made of a metal film is further provided on the light-absorbing layer. In the production of the optical absorption layer in the production of an optical information recording medium comprising a protective layer comprising a resin layer, (a) a phthalocyanine dye or a phthalocyanine dye perchlorate or periodate, and ( B)
_{^{Wherein: R + · XO 4 - (}} R + is an organic cation, X is Cl or I) and characterized by applying the coating solution consisting of a mixture of organic halide peroxide salt, represented by the spin coating method Optical information recording medium manufacturing method. 4. A light-absorbing layer made of a dye is provided on a substrate having a light-transmitting property and in which spiral pregrooves are formed, and a complex refractive index real number part n _E has n _E ≤ n _E ≤ 1.
In the production of an optical information recording medium comprising a reflection auxiliary layer made of a low refractive index resin of 6, further provided with a reflection layer made of a metal film, and further having a protective layer made of a resin layer thereon. In forming the light absorption layer and the reflection auxiliary layer, a light absorption layer forming coating solution consisting of a perchlorate or a periodate of a phthalocyanine dye, and a reflection auxiliary layer forming coating solution consisting of a low refractive index resin, Each,
A method for manufacturing an optical information recording medium, characterized by applying by a spin coating method.