JPS58112790A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To provide an optical information recording medium having a high reflectivity for wavelengths of laser rays and capable of enhancing the S/N ratio for read signals, by a method wherein a film of coloring matter comprising a cyanine coloring matter or a merocyanine coloring matter and having a bronze luster is supported on a substrate. CONSTITUTION:A cyanine coloring matter and/or a merocyanine coloring matter is dissolved into an organic solvent such as methanol, the resulting solution is applied onto a substrate by spray coating, roller coating, dipping or other similar method to produce the film of the coloring matter having a bronze luster, thereby obtaining the objective recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical information recording member having an organic dye thin film layer.

In the past, many laser-written optical information recording media have been developed. Typical examples include recording media with vapor-deposited films of metals, semimetals, and non-metals, and recording media with reflective films formed by heating a silver dry plate. In a laser recording medium that is known to contain dust, holes are formed therein by melting the metal, and its reflectivity is reduced in some spots by metal expansion and evaporation, resulting in a glossy film at the spot. The dye matrix, which can be removed, has a thin film of other coatings and a dielectric material whose refractive index changes at some point, causing light scattering when scanned by a read laser.

However, recording media with deposited films of metals, semimetals, and non-metals are generally manufactured by vacuum forming processes in a batch system rather than in a continuous system, making them expensive and requiring a large number of patches. Therefore, it is difficult to achieve quality uniformity for mass production of products.

Furthermore, since the method of forming a reflective film by heating a silver dry plate is a coating method, mass productivity is good, but there is a general opinion that the 9th BAH ratio of the silver particle dispersion system is low.

In addition, so-called "
DRAW(41reat read after wr
ite) For J media, (1) focus control and tracking control of ±1μ are required during recording and reading, so conditions such as high reflectance and strong absorption for the laser used are required. However, the use of metal has inherent problems as described above.

Therefore, as a result of extensive research into the above-mentioned problems, the inventors of the present invention have developed a recording member that satisfies the conditions (1) and (21) by using merocyanine dye as a material other than metal. Specifically, the present invention is based on the knowledge that when a solution of the above dye is coated on a substrate and dried, the dye exhibits a bronze luster on the substrate and exhibits a large reflectance in the vicinity of absorption of the dye. ing.

According to the present invention, there is provided an optical information recording member characterized in that a substrate carries a dye thin film layer having a bronze luster and comprising at least one of a cyanine dye and a merocyanine dye.

The optical information recording member of the present invention basically has a bronze-glossy thin dye film layer provided on a substrate, but other layers such as a protective layer may be placed above or below the dye thin film layer depending on the purpose. layers can be provided. What does "bronze luster" mean here?
The dye exhibits metallic reflection in a specific light wavelength range, and in reality, a reflectance of 20% or more is suitable for a convenient laser wavelength for writing and reading, and a reflectance of 30% is preferable. Bronze luster has a unique coloration that is different from the reflection of metal, but it has a very high reflectance for the wavelength of the laser light used for recording and reproduction, so it is possible to increase the amount of light for reading information. Therefore, the BAM of the read signal can be improved.

The substrate materials conveniently used in the present invention are known to those skilled in the art) and can be either transparent or opaque to the laser light used. Next, when writing and recording with a laser beam from the substrate side, it must be transparent to the writing laser beam.On the other hand, when performing convolutional distribution from the side opposite to the substrate, that is, from the surface of the recording layer, It does not need to be transparent to the writing laser light.

However, when reading and reproducing is performed using transmitted light, it must be transparent to the reading laser beam (rt#-1'). When read and reproduced using reflected light, the substrate material may be transparent or opaque to the readout laser beam. Examples of substrate materials include glass, quartz, ceramics, plastics, paper, plate-like materials, etc. The support may be of any commonly used material, such as a metal foil. In particular, plastics are preferred from the viewpoints of safety, improved recording sensitivity, XF surface properties, light weight, processability, and the like. Typical plastics include vinyl chloride resin, vinyl acetate resin,
Examples include acrylic resin, methacrylic resin, PoIJ:C stell resin, nitrocellulose, polyethylene horse chestnut resin, polypropylene resin, polyamide resin, polystyrene resin, polycarbonate resin, and epoxy resin.

The cyanine dye and merocyanine color 1g used in the present invention are commonly known as silver halide spectral sensitizing dyes. Dark dyes generally include cyanine dyes and merocyanine dyes, such as those described in the following literature.

U.S. Pat. No. 1,846,501 and Ii [1,84
No. 6,302, No. 1,942,854, No. 1,9
No. 90,507, No. 11i2, 112,140, No. 1
No. 1, 2, 165, 558, p! l No. 2,493,74
No. 7, No. 82,759,964, No. 7! 2,493,7
No. 48, No. 2,503,776, No. 2,519,
No. 001, No. 2466.761, No. 11r2,73
No. 4,900, No. 2,719,149, British Patent Collection No. 450,958, and U.S. Patent No. 4690.8
Specification No. 91.

In the present invention, the bronze-glossy pigment thin layer can be formed by, for example, dissolving the cyanine dye and/or merocyanine dye in an organic solution and spreading the solution on the substrate. Examples of the organic solvent include methanol, methylene, etc. Dichloride etc. can be used. Application is carried out by conventional coating methods such as spraying, roller coating, dipping and spinning.

The laser beam applied to the optical information recording member of the present invention must be selected depending on the absorption wavelength of the dye. Therefore, seven n
H2, Ie-0 (1, mr % H
e-Me % ruby 1 scion, cow conductor - Next, examples will be given to explain the present invention in more detail, but the present invention is not limited thereto.

EXAMPLE A 3ti-axis recording member of the present invention was prepared using the nine conditions shown in the table below to record information.
The solution was dissolved in 10 ml of solvent and filtered through a membrane filter with a diameter of 1 μm.Then, this solution was applied onto a substrate using a dipping method (dipping speed: 1.111/sec) at a predetermined rate, and an infrared lamp was used to apply the solution. When dried, an optical information recording member exhibiting a bronze luster was obtained. When the thus obtained recording member was irradiated with laser light under predetermined conditions, it was possible to record a uniform and clear shape. Ta. In the table below, the writing conditions using the Ha-No laser include a wavelength of 820 nIn and a beam diameter of α8.
4 μm, the power on the recording surface was 1.8 my, the writing time was 1 μs, and the writing conditions using a semiconductor laser were a wavelength of 6328 nm% and a beam diameter of 2-4.
For μm, the power on the recording surface is 8my and the writing time is 1
6 μsec was used. 877M I&ll constant is α5 MH
The reflectance of the nine dyes used in the above example is shown in Figures 1 and 2.
As shown in the figure.

Example number Dye Solvent
Film thickness - glass 50
-40= Acrylic
3548 55 45-80

[Brief explanation of drawings]

In the accompanying drawings, FIG. 1 and wJ21N are diagrams showing the reflectance of the dye used in the present invention. In the figure, curves ■~ correspond to each example @patent applicant
Riko Co., Ltd. - Procedural Amendment February 1, 1980 Director General of the Patent Office Shima 1) Haruki Tono1, Indication of the Case 1982 Patent Application No. 209929 2°'''A''1 Optical Information Record - Ikumaki 3. Relationship with the case of the person making the amendment Address: 1-cho Nakamagome, Ota-ku, Tokyo! 3 No. 6 Name (67
4) Ritomi Co., Ltd. 4, Agent (Monday/Day/Showa)
4 Supplement “Ef) Subject Detailed explanation of the invention in the specification column 2
Correction details 1) Correct the ``spora that is a membrane'' in the 2nd line of the 2nd page. 2) Page 8, line 8, “α1μ membrane filter”
Jtrα4μ membrane filter" and correct it. 3. Correct [H・-y・laser] in line j112 from the bottom of page 8 to “semiconductor laser.” 4) Change “semiconductor laser” on page 9, line 1112 to “R.
- Iris/Laser” is corrected. 5) In the table on page 10, replace "80" in the last row of the rightmost column with "30"
I will correct it. that's all

Claims (1)

[Claims] , at least one of a cyanine dye and a merocyanine dye.
An optical information recording member characterized by having a substrate support a dye thin film layer with a glossy bronze luster.