JPS63209042A - Optical information recording carrier - Google Patents

Abstract

PURPOSE:To prevent deterioration in properties of an optical recording layer by an adhesive agent and to permit use of the adhesive agent having high adhesive strength so that an optical information recording carriage having the good durability to peeling is obtd. by coating the optical recording layer provided to the track groove part of a transparent substrate with a film coating layer. CONSTITUTION:The optical recording layer 3 consisting of a thin org. dye film is provided with the track groove part 2 of the transparent substrate 1 having the track grooves and the film coating layer 6 consisting of a thin resin film, etc., is coated on the effective recording part 8 of the optical recording layer 3 in tight contact therewith; further, an immobilized layer 4a consisting of the adhesive agent is laminated thereon and is adhered to a protective base material 5, by which the film coating layer 6 is immobilized onto the optical recording layer 3. Contrast at the time of optical recording is thereby improved and the film coating layer acts effectively as the protective layer to the adhesive agent used for the immobilized layer so that the degree of freedom in selection of the adhesive agent layer is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical information recording carrier for optically recording and reproducing information.

[Prior Art] In recent years, with the progress of informationization in society, information recording carriers and information recording media for recording or reproducing optical information such as optical discs, optical cards, and optical tapes have become a means of efficiently handling a wide variety of information. Many playback devices have been proposed. On the information recording carrier, the binarized information is recorded as changes in reflectance, pits (
There are some methods that can be detected by converting changes in the intensity of reflected light due to changes in surface shape, such as the presence or absence of holes.

As a record carrier that relies on changes in optical reflectance, a so-called heat mode recording material has been proposed, which records by irradiating the recording layer with a spot-like energy beam such as a laser beam to change the state of a part of the recording layer. ing. These recording materials do not require any development processing after information is written.
The so-called DRAW [Direct Read After Write] allows you to read directly after writing.
(ead afterwrite)] medium that allows high-density recording and allows additional writing.

In optical information recording and reproducing devices, there is a method in which grooves are formed in advance at regular intervals on the substrate surface for track servo for writing and reading.In this method, the grooves act as guides for reading. This improves the accuracy of laser beam track control and enables faster access than conventional methods using grooveless substrates.

FIG. 4 is a schematic cross-sectional view of a conventional tightly sealed optical information recording carrier. In FIG. 4, l is a resin transparent substrate, 2 is a track groove, 3 is an optical recording layer, 4 is an adhesive layer,
5 is a protective base material.

In FIG. 4, information is recorded and read using a laser beam that optically writes and reads information through the transparent substrate l and the track groove portion 2, using minute irregularities in the track groove corresponding to the light guide groove. This allows tracking to be performed by the phase difference of the reflected light. Further, a tightly sealed optical information recording carrier can be easily produced by forming an optical recording layer 3 on the track groove 2 of the transparent substrate l and bonding the protective base material 5 with the adhesive layer 4. It is.

[Problems to be Solved by the Invention] As described above, in the conventional optical information recording carrier, an optical recording layer 3 is formed on a transparent substrate l having a track portion, and a protective base material 5 is attached via an adhesive layer 4. Although it is manufactured by thermocompression bonding, the adhesive used for the adhesive layer 4 has generally been a thermoplastic adhesive. This is because the optical recording layer 3 is often susceptible to deterioration due to substances contained in the adhesive, and it is not possible to use conventional hardening adhesives that contain polymerization initiators, sensitizers, catalysts, etc. This is because I couldn't do it. Moreover, since some thermoplastic adhesives can alter the quality of the optical recording layer 3, the selection of adhesives has been considerably limited. Therefore,
The adhesion between the transparent substrate l having the track groove portion and the protective base material 5 via the adhesive layer 4 had problems such as insufficient adhesion.

On the other hand, a tightly sealed type optical information recording carrier as shown in FIG. Compared to optical information recording carriers such as optical discs that have a spatial layer, they generally have a disadvantage of lower recording sensitivity.
For example, in the case of a hollow structure type, the recording material constituting the optical recording layer absorbs light and melts or sublimates due to light → heat conversion, forming recording bits (small holes). Optical properties such as transmittance and reflectance change significantly. On the other hand, in the case of the tightly sealed type, the physical changes described above, such as bit formation due to melting or sublimation, are considerably suppressed, and instead chemical changes (1), such as light absorption and light → Thermal conversion causes thermal decomposition of the recording material that makes up the optical recording layer, resulting in the formation of recording bits due to discoloration and decolorization.As a result, optical characteristics such as transmittance and reflectance of the recording area change, resulting in a decrease in recording sensitivity. There was a drawback to that.

The present invention has been made in view of the problems of the prior art as described above, and its purpose is to cover the optical recording layer provided in the track groove portion of a transparent substrate with a film coating layer, so that optical recording is possible. It is an object of the present invention to provide an optical information recording carrier that prevents deterioration of the layer due to the adhesive, allows the use of an adhesive with high adhesive strength, and has good durability against peeling.

Another object of the present invention is to improve the recording contrast and/or recording sensitivity of a tightly sealed optical information recording carrier using an organic dye, Another object of the present invention is to provide an optical information recording carrier having recording characteristics different from that of a hollow structure type.

[Means for solving the problem] That is, the present invention provides an optical recording layer on the track groove portion of a transparent substrate having a track groove, covers the optical recording layer with a film coating layer, and further fixes the optical recording layer thereon. This is an optical information recording carrier characterized by being formed by laminating layers and fixing a film coating layer to an optical recording layer.

The present invention will be explained in detail below.

FIG. 1 shows a tightly sealed optical information recording carrier (
A schematic cross-sectional view of the optical recording carrier (hereinafter referred to as an optical record carrier) and FIG. 2 are cross-sectional views showing an example of the overall configuration.

In the figure, 1 is a transparent substrate, 2 is a track groove, 3 is an optical recording layer, 6 is a film coating layer, 4a is a fixing layer, and 5 is a protective base material.

As shown in FIGS. 1 and 2, the optical record carrier of the present invention has track grooves 2 on a transparent substrate l having track grooves.
For example, an optical recording layer 3 made of a thin organic dye film is provided, a film coating layer such as a thin resin film is tightly coated on the recording effective portion 8 of the optical recording layer 3, and a film coating layer made of an adhesive or the like is further applied thereon. Fixed layer 4a? The film coating layer 6 is fixed on the optical recording layer 3 by laminating and adhering it to the protective substrate 5.

Note that it is possible to omit the protective base material 5 and use the vehicle as an optical disc. Further, the fixing layer 4a is formed as described above, and the W retaining layer 4a is formed.
By laminating one base material 5, it is also possible to make an optical card or an optical disk. In any case, the optical recording carrier of the present invention is characterized in that the optical recording layer 3 and the film coating layer 6 are in close contact and fixed. The protective base material 5 may or may not be present.

As the transparent substrate 1, it is preferable to use a material with few inconveniences in optical recording/reproduction, and any material with high transmittance for the light used may be used, such as acrylic resin, polyester resin, polycarbonate resin, vinyl, etc. based resin,
Polysulfone resin, polyimide resin, polyacetal resin, polyolefin resin, polyamide resin, cellulose derivative, etc. can be used.

To form the track grooves on the substrate, if the substrate is made of thermoplastic resin, a method of thermally transferring a stand bar mold by injection molding or hot press molding at a temperature higher than the melting point;
Alternatively, it is carried out by a method of photo-transferring the stubble mold by coating a photocurable resin composition on the substrate, bringing the stubber mold into close contact with the substrate, and curing the photocurable resin composition by irradiating it with ultraviolet rays or the like. be done.

In the case of the thermal transfer method, the track portion and the transparent substrate are the same body, whereas in the case of the optical transfer method, the track portion is not the same body as the transparent substrate but is bonded to the transparent substrate. Alternatively, in addition to the standby type transfer method, a resist film is formed on a transparent substrate having a transparent thin film of a desired thickness that can be etched, and the resist film is exposed through a photomask having a pattern of track grooves. It is also possible to develop the thin film to form a resist pattern, and then use the resist pattern as a mask to etch the thin film to form the track portion on the substrate.

The width of the groove of the track groove part 2 is usually 2 to 4 inches for optical cards, and usually around 0.8 to 1 for optical discs, and the track pitch is 8 inches to 15 inches for the former, and 15 inches for the latter. It is around Sμ■.

In addition, it is preferable for the depth of the groove to be an odd number multiple of the wavelength of the light source used for tracking signal detection.When considering the reproducibility of moldability of the groove, reflection due to the interference effect only due to the phase component is preferable for tracking signal detection. There are cases where it is difficult to detect the amount of light, and in such cases, the theoretical depth of the groove may be changed in order to control the detection of the amount of reflected light, taking into account changes in the intensity of the amplitude component. It is not possible to install the optical recording layer 3 in the track groove 2.
When forming an optical recording layer, it is necessary to improve adhesion, improve optical properties (e.g. transmittance and reflectance), improve gas barrier properties against gas release from the substrate, improve storage stability of the optical recording layer, and prevent deterioration due to reproduction light. Primer treatment, formation of an undercoat layer, corona treatment, UV-ozone treatment, plasma treatment, etc. may be performed for the purpose of improving heat conductivity.

The optical recording layer 3 is formed in the vicinity of the wavelength of the light to be used, for example, the wavelength of the energy beam of the reproduction light is 65 on- or more, especially 70 on-
In the case of 0 to 900 nm, it is preferable that there is a large difference in reflectance between the bits, which is the recording part, and that of the unrecorded part, and in order to record, it is necessary that there is absorption in the above wavelength range. is necessary.

In addition, it is preferable that the energy required to cause a change in reflectance due to energy beam irradiation is small.
It is preferable that the reflectance of the bits, etc.) and the unrecorded area does not change easily.

For example, Te, Sb, Mo, Ge, V, Sn
oxides such as Te-5n, compounds such as Te0x-Ge, Te-CH,, Te-C5, etc.

Te-styrene, 5n-3O,, Gem-3n, 5
Composites of metals such as nS-3 and organic compounds or inorganic sulfides, materials in which metal particles such as silver are dispersed in thermoplastic resins such as nitrocellulose, polystyrene, and polyethylene; Metal particles aggregated on the surface, chalcogen or colored type 1lloO, -Cu
, MoO, -3n-Cu, etc. are used.

Furthermore, organic thin films whose optical properties can be changed by energy beams can be applied continuously using a solution or a dispersion system, which is preferable for mass production.

For example, anthraquinone derivatives (especially those having an indathrene skeleton), dioxazine compounds and their derivatives, triphuedithiazine compounds, phenanthrene derivatives, cyanine compounds, merocyanine compounds, biryllium compounds, xanthine compounds, triphenylmethane compounds, croconium dyes, azo dyes, crocones, azines, indigoids, polymethine dyes, azulenes.

Squarium derivatives, sulfur dyes and metal dithiolate complexes may be mentioned.

In addition, a dye composition may be used in which these dyes are mixed with a quencher for the excited species of these dyes. and select. The amount added can range from several weight percent to 50 weight percent based on the dye, but if it is small, the effect as a quencher will not be seen much, and if it is added in excess of 50 weight percent, the absolute amount of the heat mode recording material will be reduced. A decrease in sensitivity is observed from the decrease in . Therefore, it is preferable to use 10% to 30% by weight per dye, and in particular, around 20% by weight is preferable for a high effect without deterioration of sensitivity.

Such quenchers include various metal chelate compounds, especially Zn, Cu, Ni, Cr, Go, In, P
d, polydentate ligands with Zr as the central metal, such as N4.
NtOa, NtSt.

Concave ligands such as S4.0□8m, 04, or s, o
, NO2゜NS*, Os, 803, etc. and other ligands 1 such as water, ammonia, halogen, phosphine, amine, arsine, olefin, etc., or two bidentate ligands N, In addition to the four-coordinate type of NO, 0□es2, those consisting of biscyclopentadienyl ligands, cyclopentadienyl-tropylinium ligand systems, or combinations of the above, various aromatic amines and diamines, nitrogen-containing aromatics, and onium salts thereof, such as aminium salts, diimonium salts, pyridinium salts, imidazolinium salts, and quinolinium salts. Furthermore, biryllium salts, which are oxygen-containing aromatic salts, etc. may be used, and it is also possible to use a combination of two or more of these quenchers. The composition ratio can be changed as appropriate by taking into account factors such as reflectance and transmittance), recording sensitivity, etc.

Optical recording layer 3 made of the above organic dye or dye composition
may be formed by a known coating method, such as dip coating, spray coating, spinner coating, bar code coating, blade coating, roll coating, curtain coating, etc. The thickness of the optical recording layer 3 is approximately
Approximately 500 to 2000A, preferably 100OA
#Later.

In particular, from the viewpoint of recording sensitivity, it is desirable that the film be thin, but from the viewpoint of S/N ratio during reproduction, it is desirable that it be thicker, and the optimum film thickness differs depending on the type of dye.

The film coating layer 6 in the present invention is a resin thin film, and does not undergo any substantial change at the contact interface with the optical recording layer, at least in the unrecorded state. It is necessary to prevent the adhesive used for the fixing layer from affecting the optical recording layer, and also to prevent the influence of the adhesive used in the fixing layer on the optical recording layer. It is desirable that the film be easily deformed by the heat energy applied to it. In this respect, a St plastic resin thin film is preferable as a film coating layer.For example, acrylic resin, polyester resin, polycarbonate resin, vinyl resin, polysulfone Resins, polyimide resins, polyacetal resins, polyolefin resins, polyamide resins, vinylidene resins, cellulose derivatives, or their copolymers such as vinyl chloride-vinyl acetate copolymers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid Examples include ester copolymers, vinyl acetate-acrylic acid ester copolymers, and styrene-butadiene copolymers.

Furthermore, any material that can be used for the protective substrate 5, such as a sheet-shaped resin or a metal thin film, that satisfies the above conditions can be used.

In addition, the adhesive may be one that satisfies the above conditions; in other words, the adhesive used for the fixing layer will be used twice,
For example, a sheet-like thermoplastic adhesive can be used for the film covering layer 6.

The above-mentioned resin thin film is easily available in the form of a film and has a uniform thickness, but the smoothness of its surface in particular affects the recording characteristics of the optical recording layer 3 of the optical record carrier. . If the smoothness is poor, the S/N ratio will be poor and sufficient signal detection will be difficult.

Further, when detecting a signal by a change in transmittance, it is desirable that the material be transparent to the reproduction light used.

When detecting a signal based on a change in reflectance, there are no limitations on the reproduction light used.

The thickness of the film coating layer varies depending on the material used, but 1
Usually 0.05 to 1, preferably 0.1 to 50, is desirable.

In addition, when covering the film coating layer 6 with the fixing layer 4a, the surface of the resin s film constituting the film coating layer 6 is modified only on one side in order to improve the adhesion and adhesion of the interface between both layers. Alternatively, a thin resin film with an adhesive layer that also serves as an adhesive layer may be used. In any case, it is important that the resin thin film at the contact interface with the optical recording layer 3 does not substantially deteriorate the optical recording layer in an unrecorded state.

The fixing layer 4a of the present invention is used for the purpose of fixing the film coating layer 6 or for bonding with the protective substrate 5. For example, for the purpose of fixing, the fixing layer 4a is Thermoplastic film or dry film type thermoplastic adhesives with low softening temperatures or low melting points can be used. Alternatively, the adhesive layer may be a thermoplastic adhesive, a photocurable adhesive, a thermosetting adhesive, a combination of light and heat curable adhesive, an adhesive adhesive, or a protective layer with one side of these adhesives applied in advance. The base material 5 may be used for bonding, or the film coating layer 6 may be used as it is as the fixing layer 4.
It can also be used as a.

Next, specific examples of adhesives used for the second fixing layer 4a include vinyl acetate type, vinyl acetate acrylic type, vinyl acetate copolymer type, vinyl acetate emulsion type, acrylic type, acrylate type, and acrylic adhesive type. Polymerization type, ethylene type, ethylene vinyl acetate type, ethylene vinyl acetate copolymer type, polyethylene type, methylene chloride type, polyamide type, polyamide-amine type, polyimide type, urea type, epoxy type, epoxyurethane type, epoxy acrylate type,
Urethane acrylate type, polyester type, chloroprene type, chloroprene rubber type, nitrile type, nitrile rubber type, urethane type, vinyl urethane type, polyurethane type,
Olefin type, cyanoacrylate type, alkyl acrylate type, vinyl chloride type, phenol type, SBR type (styrene butadiene rubber), polyol type, silica alumina type, synthetic rubber type, emulsion type, oligoester type, cellulose type, formaldehyde type , UV curing type,
Organic solvents, styrene-butadiene type, Freon TA type, etc. can be used. Bonding methods that require energy such as heat, light, and electron beams are also effective as long as the energy does not deteriorate the function of the optical recording material.

Conventionally, it was impossible to use adhesives that would attack the optical recording layer, such as hardening adhesives, adhesive adhesives, and amide thermoplastic adhesives, but the film coating layer of the present invention Since it also acts as a barrier layer to protect the optical recording layer, the degree of freedom in selecting the adhesive has been greatly increased.

As the protective base material 5, any material that can be used as a normal protective base material can be used, and specifically, polyvinyl chloride, fluorine-substituted ethylene polymer, vinyl chloride-vinyl acetate copolymer, polychlorinated Vinylidene, acrylic polymers such as polymethyl methacrylate, polystyrene, polyvinyl butyral, acetyl cellulose, styrene-butadiene copolymer, polyethylene, polypropylene, polycarbonate, epoxy acrylonitrile-butadiene
A styrene copolymer or the like is used.

In some cases, iron, stainless steel, aluminum, tin,
A wide variety of materials can be used depending on the purpose, such as metal sheets such as copper and zinc, synthetic paper, paper, fiber-reinforced plastics, composites of metal powders such as magnetic materials and plastics, and ceramics. Of course, those used for transparent substrates may be used.

These protective substrates 5 may be subjected to corona discharge treatment, if necessary.
Pretreatment to improve adhesion such as plasma treatment, primer treatment, ozone treatment, etc. may be performed.

Next, FIG. 3 shows another example of the optical recording carrier of the present invention. In FIG. 3, transparent polycarbonate is used for the transparent substrate l, dye is used for the optical recording layer 3, and the entire surface of the transparent substrate l is An optical recording layer 3 is formed thereon.

Next, the optical recording layer effective portion 7 of the optical recording layer 3 above the track groove portion 2 is covered with a film coating layer 6, and a fixing layer 4a is formed thereon using a polyamide adhesive that corrodes the dye. Furthermore, a protective base material 5 is laminated as the outermost layer. In the optical recording carrier constructed in this way, the adhesive invades the optical recording layer 3 that is not protected by the film coating layer 6.
High adhesive strength can be obtained between the transparent substrate l and the protective base material 5 even though the optical recording layer 3 is interposed therebetween.

However, the effective optical recording layer s7, which is the portion protected by the film cover 113it6, can maintain the reflectance of 8301■ before adhesion.

In the optical record carrier having such a structure, as shown in FIGS. 1 and 2, there is no need to partially form the optical recording layer 3 on the transparent substrate l, thereby simplifying the cart manufacturing process. Can be done.

[Function] Regarding the pioneer #R carrier using an organic dye, a tightly sealed optical recording carrier can be used as an optical disc of a conventionally known hollow structure type, for example, an optical disc provided with an air layer (or space layer). For example, in the case of a hollow structure type, the recording material constituting the optical recording layer absorbs light and the material melts due to light → heat conversion. Alternatively, as a result of forming recording bits (small holes) by sublimation, optical characteristics such as transmittance and reflectance of the recording portion change significantly. On the other hand, in the case of a tightly sealed type, the above-mentioned physical changes (shape changes such as bit formation due to melting or sublimation) are considerably suppressed, and instead chemical changes, such as light absorption and light →It was discovered that thermal conversion causes thermal decomposition of the recording material that makes up the optical recording layer, resulting in the formation of recording bits due to discoloration and decolorization, resulting in changes in optical properties such as transmittance and reflectance of the recording area. It is.

For this reason, it has been found that recorded bits tend to have higher recording contrast than recording bits and require less energy for recording, that is, have higher recording sensitivity. This is thought to be mainly because the melting and sublimation temperature of the organic dye is lower than the decomposition temperature.

Therefore, a large amount of energy is required for discoloration and decolorization caused by one decomposition, and this is thought to be the cause of the decrease in contrast and low recording sensitivity. In this way, in tightly sealed optical record carriers, it is possible to suppress bit recording caused by chemical changes such as discoloration or bleaching, and to recover bit recording caused by suppressed physical changes. This makes it possible to improve contrast and recording sensitivity.

Since the film coating layer 6 in the present invention is composed of a resin thin film that is easily deformed by heat, the light generated by light absorption→
It is believed that it is easily deformed by the heat generated by thermal changes, and helps to some extent physical deformation due to melting or sublimation of the optical recording layer.

It has also been found that the film coating layer 6 has better constant-temperature durability than an optical recording carrier with a hollow structure, and the film coating layer also serves as a protective layer for the optical recording layer. It is thought that it acts as a barrier layer to prevent deterioration due to residual oxygen, moisture, etc.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Transparent resin substrate (thickness 0.451 m, polycarbonate board containing ultraviolet absorber, Panlight 211, Kijin Kasei ■
neopentyl glycol diacrylate (7
0 parts by weight), bisphenol-based epoxy acrylate (
30 parts by weight) [bifunctional acrylate obtained by adding acrylic acid to Epicoat 828 (trade name, manufactured by Yuka Shell Epoxy ■)] and benzoin isopropyl ether (1 part by weight). Track grooves were formed by a molding method. Track groove 3gm)
An optical cart substrate was obtained which consisted of striped track grooves with a rack groove pitch of 13 μm and a track depth of 13 GOA.

The optical card substrate was dried for 3 hours at 120°C to complete the removal of remaining 70% and polymerization, and then spun with Colcoat 103X (manufactured by Colcoat ■) as an undercoat.
Coated by the method, dried at 50°C for 3 hours,
A silica thin film of A was formed. On the undercoat layer, a solution of a dye of the formula (I) shown below dissolved in dichloroethane at a concentration of 6 wt% was coated by a spin code method to a thickness of 10%.
An optical recording layer of 0OA was formed.

On top of the optical recording layer, a strip of polyethylene terephthalate (Lumirror, manufactured by Toshi) with a thickness of 5 μm was layered, and then a thermoplastic adhesive (ethylene-vinyl acetate dry film) with a thickness of 50 μm was layered. As an opaque card base material, 0
．． 3-Moldy white polycarbonate (Taflon, manufactured by Idemitsu Petrochemical Co., Ltd.) was layered and thermocompression bonded using a hot roll with a surface temperature of 110°C to create an optical card.

Next, using a semiconductor laser beam of 830 nm from the transparent substrate side of the optical card, the power of the laser beam was 3.9 mW,
When recording was performed with a write pulse If@100gg under the conditions of a spot diameter of 4.5 mm and a card feed speed of 13011 layers/S, a contrast ratio of 0.65 was obtained. However, the contrast ratio represents the ratio of the reflectance of the non-recorded area to the value obtained by subtracting the reflectance of the recorded area from the reflectance of the non-recorded area.

(I) Example 2 A track groove of 0.84 m was created using the injection molding method.
, track pitch 1.8μ, track groove depth 6
00A grooved acrylic disk board (130mm diameter)
, inner diameter 15mm) D, Colcoat 103X (:1
/L/Coat-made) is spin-coded to a thickness of 200A.
An undercoat layer consisting of a thin silica film was formed.

In addition, as a dye and a quencher of the formula (■) shown below,
2% by weight of dichloroethane to which 20% by weight of N,N,N',N'-tetrakis(p-di-n-butylaminophenyl)-p-phenylenediimonium perchlorate (formula (■)) was added based on the dye. The solution was applied by a spin code method to form an optical recording layer with a thickness of 900 Å.

On this optical recording layer, a diameter of 125 m, an inner diameter of 30 mm,
A ring-shaped polyester film (Tetron F, manufactured by Teijin Kasei Co., Ltd.) with a thickness of 5 mm was placed on top, and a triacetate film with adhesive (70 mm) with a diameter of 130 m and an inner diameter of 15 mm was placed on top.
μ layer thickness) was pressed and laminated at room temperature to obtain a tightly sealed optical disc.

Recording was performed from the transparent substrate side of the optical disc using an 830n layer semiconductor laser beam at a laser beam power of 8+sll, a recording frequency of 2 MHz, and a rotation speed of 1.80 Orpm, and a contrast ratio of 0.75 was obtained.

An accelerated storage experiment was performed in which an optical disc with optical recording was left at 60°C and 90% (relative humidity) for 1,000 hours, and the reflectance G/N value was measured. is 5
It was 1 dB.

However, A r = -CD-N (nBu) 2 Example 3 Instead of the adhesive-attached triacetate film (70H thickness), gi paper thermoplastic dry film (ethylene-
An optical disc was produced in exactly the same manner as in Example 2, except that the disc was laminated by thermocompression bonding at 110° C. using vinyl acetate (501 Lm thick), and the GL pattern paper was clouded to obtain an optical disc. As a result, a contrast ratio of 0.73 was obtained.

Comparative Example 1 An optical card was prepared in exactly the same manner as in Example 1 except that the 5 μm polyethylene terephthalate film coating layer was removed, but a contrast ratio of only 0.22 L was obtained.

Comparative Example 2 An optical disc was prepared in exactly the same manner as in Example 2, except that the El polyester film serving as the film covering layer was removed.
The reflectance decreased and recording was impossible. Comparative Example 3 An optical disc was prepared in exactly the same manner as in Example 3, except that the 5% polyester film that was the film m1 layer was removed. A ratio of 0.28 L was not obtained.

Comparative Example 4 A disk substrate having an optical recording layer was produced in exactly the same manner as in Example 2 up to the formation of the optical recording layer. Styrene-divinylbenzene resin beads with a particle size of 300 μm are placed in a ring shape with a width of 2 μm on the inside of the outer periphery and the outside of the inner periphery of a disc-shaped acrylic substrate (diameter 130 mm, inner diameter 15 layers). Apply a UV curable adhesive containing dispersed
The disk substrates with the precursor R layer were stacked on top of each other, the portion corresponding to the optical recording layer was shielded from light, and UV light was irradiated to harden the annular portion, thereby producing an optical disk having a spatial layer.

After recording the obtained optical disc under the recording conditions shown in Example 2, under the conditions of 60° C. and 90% (relative humidity), 1
After leaving it for 000 hours and performing an accelerated storage test, the reflectance C
When the /N value was measured, the C/N value decreased to 39 dB.

Example 4 A track groove of 2.0 H and a track pitch of 12. O1 &s, a transparent substrate provided with a track groove with a track depth of 2500 A, was coated with a dye having the structure of the following formula (ff) as a bar code to the track groove to form an optical recording layer with a film thickness of 0.1 μm. Formed.

＾r　　　　＾“ However, ＾rwa+NEt”.

At this point, the reflectance of 830n- light at the interface between the polycarbonate groove and the dye layer was measured from the polycarbonate side and found to be 15%.

Next, using ethylene vinyl acetate adhesive as the adhesive and polycarbonate with a thickness of 300# as the protective base material,
When laminated and bonded at 0°C, there was no change in the reflectance of light at 830 nm, but the adhesive strength between the polycarbonate with the track grooves and the polycarbonate as the card base material was low.

When an optical card was prepared in the same manner as above except that the adhesive was changed to a polyamide-based adhesive in order to increase the adhesive strength, a high adhesive strength was obtained, but the light reflectance of %830n- was 3%.

Therefore, when we covered the effective part of the optical recording layer formed on the track groove with 51 &Ho's polyethylene terephthalate film and created a cart using polyamide adhesive, we found that it had a light reflectance of 15% and sufficient adhesive strength. was able to obtain.

Possible causes of the dyes in polyamide adhesives include the amine compounds they contain, additives such as stabilizers, plasticizers, inhibitors, and initiators, gases generated by heat, and residual monomers. It is clear that the polyethylene terephthalate film of 5-■ suppresses this effect.

[Effects of the Invention] The optical recording carrier of the present invention has the optical recording layer provided on the track grooves of a transparent substrate covered with a film coating layer, further laminated with a fixing layer on top of the optical recording layer, and the film coating layer is formed into an optical recording layer. Since it is immobilized, it is possible to improve the contrast during optical recording.

Furthermore, the film coating layer effectively functions as a protective layer for the adhesive used in the fixing layer, increasing the degree of freedom in selecting the adhesive.

Furthermore, the tightly sealed optical disc, which does not require any conventional means for providing a space layer, is advantageous in terms of manufacturing process and also has the effect of preventing deterioration due to oxygen and moisture remaining in the space layer.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a tightly sealed optical record carrier of the present invention, FIG. 2 is a cross-sectional view showing an example of its overall configuration, and FIG.
FIG. 4 is a cross-sectional view showing another example of the optical record carrier of the present invention, and FIG. 4 is a schematic cross-sectional view of a conventional tightly sealed optical record carrier. 1...Transparent substrate 2-)-Rack groove 3...
・Optical recording layer 4...Adhesive layer 4a = fixing layer
5... Protective base material 6... Film coating layer
7... Optical recording layer effective section 8... Recording effective section

Claims (2)

[Claims] (1) An optical recording layer is provided on the track groove of a transparent substrate having a track groove, the optical recording layer is covered with a film coating layer, a fixing layer is further laminated on top of the film coating layer, and the film coating layer is replaced with the optical recording layer. An optical information recording carrier characterized by being immobilized on. (2) The optical information recording carrier according to claim 1, wherein the film coating layer is a resin thin film that does not cause any substantial change in the optical recording layer in an unrecorded state at the contact interface with the optical recording layer.