JPH05177947A - Optical recording medium - Google Patents

Abstract

PURPOSE:To provide an optical recording medium wherein an optical absorption layer is composed of coloring matter which has excellent light fastness and is good in solvent solubility. CONSTITUTION:After advancing of reaction for making sulfonyl chloride at 130-135 deg.C with copper phthalocyanine into chlorosulfonic acid, thionyl chloride is made to react therewith at 80 deg.C, and sulfonyl chloride material of the copper phthalocyanine is obtained. Then, the sulfonyl chloride material of the copper phthalocyanine together with ethoxyethyl amine is dispersed in ice water, stirred for one night, and a separated precipitate is obtained by filtration. After washing with water, it is dried at 70 deg.C by hot air for 10h, and alkoxyalkylene sulfonamide derivative coloring matter of the copper phthalocyanine is obtained. Then, 5% ethanol solution of the coloring matter obtained thus is prepared, and that solution is spread on a disk consisting of polycarbonate resin by a spin coat method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium, and more particularly to a heat mode write-once type optical recording medium.

[0002]

2. Description of the Related Art An optical disc is a read-only type (Read Onl
y), write-once type (Write Once type) and rewrite type (Rewritabl
There are three types, e), and the recording materials (optical recording media) are roughly classified into inorganic type and organic type, and the recording principle is divided into three types: perforation, phase change and bubble. Optical recording using laser light includes heat mode recording and photon mode recording.

Among the optical discs classified as described above, conventionally, in the case of write-once type optical recording using a semiconductor laser beam, a heat mode recording mode based on the principle of punching (pit formation) has been mainly used. Further, in recent years, as an optical recording medium, organic dyes having low toxicity and high coatability by spin coating have been widely used, and as organic dyes, cyanine dyes, phthalocyanine dyes, naphthoquinone dyes,
There are triphenylmethane-based and squarylium-based dyes, but cyanine-based and phthalocyanine-based dyes have been widely used.

However, although the cyanine dye has a sufficient solvent solubility required for spin coating, it has a drawback that the recorded and unrecorded materials have poor light resistance. on the other hand,
Phthalocyanine dyes generally have good light resistance, but have the drawback of insufficient solvent solubility.

As a countermeasure for these drawbacks, Japanese Patent Laid-Open No. 62-14
Although the inventions disclosed in 6682, JP-A-62-146683, JP-A-63-39388 and JP-A-63-149188 are known, none of them have sufficiently solved the above-mentioned drawbacks, and Since aromatic solvents and halogenated hydrocarbon solvents were mainly used, breakage between the grooves was predicted considering the influence on the substrate, which was not preferable. Considering the stability with respect to the polycarbonate resin or polyacrylate resin which is the substrate material, the solvent is preferably alcohol or cellosolve.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and an optical recording medium in which the light absorption layer is composed of a dye having excellent light resistance and good solvent solubility. The purpose is to provide.

[0007]

Means for Solving the Problems As a result of intensive studies for achieving the above object, the present inventors have found that an alkoxyalkylene sulfonamide derivative dye of metal phthalocyanine
The inventors have found that they have good solubility in alcohol-based or cellosolve-based solvents and also have excellent light resistance, and have reached the present invention.

That is, the present invention is an optical information recording medium having a light absorbing layer composed of an organic thin film, wherein the light absorbing layer is composed of an alkoxyalkylene sulfonamide derivative dye of metal phthalocyanine. A recording medium is provided.

[0009]

The sulfonamide group represented by the general formula of Chemical formula 1 is
When R ₁ and R ₂ in this general formula are H, water solubility appears, and when R ₁ and R ₂ are alkyl groups, non-polarity appears, and solubility in polar solvents such as methanol and ethanol is high. become worse.

[0010]

[Chemical 1]

Therefore, as a result of earnest research by the present inventors,
R ₁ in the above general formula is H or lower alkyl,
It has been found that when R ₂ is (CH ₂ ) _n OR (R is a lower alkyl group and n is a natural number), the solubility in alcohol-based or cellosolve-based solvents is improved.
By substituting R ₁ and R ₂ in the sulfonamide group with these groups, they have a common part with alcohols and cellosolves, and the solubility in alcohols and cellosolves is improved by hydrogen bonds and van der Waals forces. It is thought to do.

That is, the alkoxy alkylene sulfonamide of metal phthalocyanine that constitutes the optical recording layer of the optical recording medium of the present invention can be represented by the general formula
As can be seen from this general formula, since it has the sulfonamide group, it has good solubility in alcohol-based solvents and cellosolve-based solvents, and a good coating film without leaving a substrate made of polycarbonate resin or polyacrylic resin. Can be obtained.

[0013]

[Chemical 2]

In this general formula, R ₁ and R ₂
Is hydrogen or a lower alkyl group, M is a metal element, and n is a natural number.

The alkoxy alkylene sulfone amide of metal phthalocyanine that constitutes the optical recording layer of the optical recording medium of the present invention may have excellent light resistance similarly to the conventionally used phthalocyanine dyes. It has been confirmed by experiments by the present inventors.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by the following examples.

[0017]

EXAMPLES An example of a method of manufacturing the optical recording medium of the present invention is shown below. First, copper phthalocyanine was added little by little to chlorosulfonic acid at 30 ° C. or lower. Then add this to 70-75
The temperature was raised to 130 ° C. and the mixture was stirred at that temperature for 1 hour, then the temperature was raised to 130 to 135 ° C. over 1.5 hours, and the mixture was stirred at this temperature for 4 hours to proceed the sulfonyl chloride formation reaction of copper phthalocyanine. Next, after cooling this to 80 degreeC, thionyl chloride was added little by little and it stirred at 75-80 degreeC for 4 hours. Next, this was cooled to room temperature and then poured into ice water, and the deposited precipitate was filtered. After filtration, the obtained precipitate was thoroughly washed with ice water until it became neutral to obtain a sulfonyl chloride form of copper phthalocyanine.

Next, 9.71 parts of the sulfonyl chloride of copper phthalocyanine and 7.12 parts of ethoxyethylamine obtained as described above were dispersed in 50 parts of ice water and stirred overnight. After stirring, this solution was filtered to obtain a deposited precipitate,
The obtained precipitate was washed with water and then dried with hot air at 70 ° C. for 10 hours to obtain an alkoxyalkylenene sulfonamide derivative dye of copper phthalocyanine represented by the general formula (3). In addition,
The substituents R ₁ and R ₂ in the above general formula are shown in Table 1.

[0019]

[Chemical 3]

[0020]

[Table 1]

Next, a 5% ethanol solution of the alkoxyalkylene sulfonamide derivative dye of copper phthalocyanine obtained as described above was prepared and applied onto a disk made of a polycarbonate resin by spin coating to give a film thickness of 70.
An optical recording medium having an optical recording layer of nm was prepared. The solubility (amount (g) dissolved in 100 g of ethanol) at the time of preparing the 5% ethanol solution was measured and is also shown in Table 1.

On the optical recording medium manufactured as described above,
Using a semiconductor laser beam with a wavelength of 780 nm, a linear velocity of 1.2 m /
A signal was recorded at a recording frequency of 0.5 μHz for 2 seconds, and the recording power and C / N at the time of recording were measured and are also shown in Table 1.

[0023]

The dye constituting the light absorption layer in the optical recording medium of the present invention has good solubility in a solvent, particularly an alcohol-based or cellosolve-based solvent, so that a substrate made of a polycarbonate resin or a polyacrylic resin can be used without being scratched. It is possible to obtain a good coating film and is excellent in light resistance.

Front page continuation (72) Inventor Toru Fujii 6-16-20 Ueno Taito-ku, Tokyo Taiyo Denki Co., Ltd.

Claims (1)

[Claims] 1. An optical information recording medium having a light absorbing layer made of an organic thin film, wherein the light absorbing layer comprises an alkoxyalkylene sulfonamide derivative dye of metal phthalocyanine.