JPS62172543A - Optical recording element - Google Patents

Abstract

PURPOSE:To obtain an optical recording element having a reflective layer or intermediate layer which has an excellent shelf life and adhesiveness by laminating a recording layer via the reflective layer or intermediate layer consisting of a prescribed low mol. org. compd. film on a substrate surface. CONSTITUTION:The reflective layer or intermediate layer is formed on the substrate by a plasma polymn. treatment of the low mol. org. compd. The recording layer is formed thereon. The reflective layer or intermediate layer obtd. by the plasma polymn. treatment is extremely hard, has less pinholes and has excellent adhesiveness to the substrate of a metal, polymer, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording device for imprinting and reading information using a light beam, and more particularly to a constituent material of the device consisting of a laminate of thin films. .

[Conventional technology]

Recording methods using optical recording elements are roughly divided into two types, one of which is a recording method by hole formation, as shown in Figure 1, and the other is a recording method using phase transition, as shown in Figure 2. This is a recording method based on crystal form transition. In the former case, as shown in FIG. 1, a reflective layer 2 is provided on a substrate 1, and a recording layer 6 is provided thereon.

As the substrate, a metal substrate, a glass plate, or a hard plastic such as PMMA is used. As the reflective layer, a metal vapor deposition film such as Kl, Ag, Au, Cr, etc. is used. Generally, the adhesion between the reflective layer and the substrate is poor, so the reflective layer is deposited on a substrate on which an undercoat layer has been provided in advance, or on a substrate that has been treated with a silane or titanium coupling agent. As the recording layer, a low oxidation chalcogenide, a low boiling point polymer, or a mixture of these with a dye exhibiting spectral sensitivity to the light used is used.

In this recording method, the recording layer is irradiated with light, and the irradiated heat causes the recording layer to partially evaporate or deform due to thermal movement, exposing the reflective layer.

In the latter recording method, a recording layer 6 is provided on a substrate 1 via an intermediate layer 21 as shown in FIG. It undergoes a phase change into quality. This kind of recording layer is 'l'
e3eQe amorphous film, 'l'eQx.

TeOxGe, TeOxSn, 5b2Se, thin film, etc. can be used. Such optical recording elements also have poor adhesion between the substrate and the recording layer (an undercoat layer is provided, or a pretreatment with a coupling agent, etc. This is not only to protect the recording layer from physical (scratch) and chemical (oxidation) deterioration, but also to protect the reflective layer from physical and chemical deterioration in the hole-forming recording method. In either recording method, the recorded signal is read based on the difference in the reflectance of the recorded portion 61 and the non-recorded portion 620 with respect to the reproduction light.

[Problem that the invention seeks to solve]

Problems with the above-mentioned conventional optical recording element include, first, the adhesion between the substrate, the reflective layer, and the recording layer.

When glass or polymer is used as the substrate, the adhesion between the substrate and the metal reflective layer is particularly poor. Furthermore, the adhesion between the metal reflective layer and the recording layer, and between the substrate and the recording layer also becomes a problem. Next, in the optical recording method using hole formation, not only the mechanical and chemical strength of the recording layer but also the mechanical and chemical strength of the reflective layer become a problem.

Conventionally, AA, Ag, and A are used as reflective layers.
These are vapor-deposited films of u, Cr, etc., but these are all inferior in mechanical strength. KL, Ag, Au, etc. are very soft metals with a Vickers hardness of 20 to 50. Cr is harder than these, but 1. Vickers hardness is at most 170~
It is about 190. If the reflective layer of the optical recording element is scratched, there is a high possibility that erroneous reading will occur during reproduction.

On the other hand, optical recording elements need to have excellent storage stability. Al and Ag have poor oxidation resistance and sulfidation resistance. When Cr is stored for a long period of time, its chemical strength becomes a problem, such as the surface becoming cloudy. Chemical deterioration causes a decrease in reflectance due to long-term storage of the reflective layer, resulting in poor sensitivity during readout. Currently, intermediate layers or surface protective layers are used to solve these problems, but nothing satisfactory has been achieved. An object of the present invention is to provide an optical recording element having a reflective layer or an intermediate layer with excellent storage stability and adhesion.

[Means for solving problems]

In order to solve the problems of conventional optical recording elements, the present invention uses a hard thin film of a low-molecular organic compound obtained by plasma polymerization as a reflective layer or adhesion layer, which has excellent adhesion, mechanical and chemical strength, and It is an object of the present invention to provide an optical recording element whose characteristics do not change even when stored for a long period of time. Examples of the substrate used include metal plates such as KL, glass plates, ceramics, and polymers such as PMMA, polycarbonate, polycellulose acetate, PET, and polyimide. As the recording layer, thermoplastic films such as polystyrene, polyethylene, and nitrocellulose, metalloids such as Te, Bi, and se, Se-T
e-AS, Te-As, Zn-8, As-8
e.

Ge-8-P, Ge-3-Cu, Ge-8-
Examples include films of chalcogen compounds such as Na, As-8-I, and Ge-8e, and films containing these substances with a sensitizer added. Furthermore, a protective layer may be provided to protect the recording layer. The plasma polymerized film of the present invention is used as the reflective layer 2 in FIG. 1 or the intermediate layer 21 in FIG. 2.

Examples of low-molecular organic compounds used in plasma polymerized membranes include alkanes, alkenes, alkynes, vinyl monomers, and aromatic hydrocarbons. These may be unsubstituted or substituted with halogen or the like. Furthermore, these can be used in any state: gas, liquid, or solid. The organic compound thin film obtained by plasma polymerization is very hard, has few pinholes, and has a metallic luster. The present inventors further discovered that these films have excellent adhesion to metals and polymers.

〔Example〕

A plasma polymerized film was formed using methane gas on a smooth and cleaned acrylic plate. The film thickness was 1000 pieces.

On the other hand, as a comparative example, Al was vacuum-deposited on a similar acrylic plate to obtain a film having a thickness of 100A.

In order to examine the adhesion, a peel test was conducted using the substrate eye test method, and the polymer film showed sufficient adhesion, but most of the Al film peeled off.

Next, the hardness was checked using a Vickers hardness meter, and the hardness was 4000 for the polymer film and 20 for the Al film.

The reflectance after vapor deposition was 52% for the polymer film and 84% for the Al film. (Wavelength 850nrn) Next, a storage test was conducted. 7
When the polymer film was left under conditions of 0°C and 90% relative humidity for two weeks and its reflectance was examined, it was 52%, A11! The film was 6%.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, it is possible to obtain an optical recording element with excellent adhesion, high reflectance, and high storage stability.

[Brief explanation of drawings]

The drawings are all sectional views of essential parts of a general optical recording element common to the present invention and the prior art. , - One voice 1...Substrate, 2...Reflection layer, 21...
...Intermediate layer, 6...Recording layer, 61...
... Recording Department, Figure 1 Figure 2 Procedural Amendment (Method) % Formula % 1. Indication of the case 1985 Patent Application No. 13263 2. Name of the invention Optical recording element 3. Person making the amendment Related Patent Applicant Address 2-1-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo Telephone (03)
) 342-1231,, (1', 1 4. Date of amendment order: March 25, 1985 (shipping date) 5. Column 6, "Brief explanation of drawings" of the specification subject to amendment. 6. Contents of amendment. The column "Brief explanation of the drawings" is corrected as follows: 41 Brief explanation of the drawings All of the drawings are cross-sectional views of main parts of a general optical recording element common to the present invention and the prior art, and the first The figure shows an optical recording element that records information by forming holes in the recording layer.
FIG. 2 shows an optical recording element in which information is recorded by changing the quality of the recording layer. ”.

Claims (1)

[Claims] 1. An optical recording element in which a recording layer is laminated on the surface of a substrate via a reflective layer or an intermediate layer, wherein the reflective layer or the intermediate layer is made of a low-molecular organic compound film obtained by plasma polymerization.