JP2523303B2 - Optical recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium, particularly to a heat mode optical recording medium.

Prior Art and its Problems Optical recording media are characterized in that the recording media do not wear and deteriorate because the write and read heads are not in contact with the media. For this reason, various optical recording media have been researched and developed. .

Among such optical recording media, heat mode optical recording media have been actively developed because they do not require development processing in a dark room.

This heat mode optical recording medium is an optical recording medium that uses recording light as heat. As an example, a small hole called a pit is formed by melting and removing a part of the medium with recording light such as a laser. There is a pit formation type in which a pit is formed and writing is performed, information is recorded by the pit, and the pit is detected by reading light to perform reading.

Such pit formation type media, especially
So far, most of the devices that use a semiconductor laser as a light source that can miniaturize the device have a recording layer made of a material mainly containing Te.

Further, in recent years, since Te-based materials are harmful, need to be more sensitive, and manufacturing costs have to be made lower, Te-based organic materials, instead of Te-based materials, are mainly composed of dyes. The number of proposals and reports on media using the recording layer of the system is increasing (JP-A-60-203488, etc.).

A pit-forming type optical recording medium having such a recording layer of a dye or the like preferably has a so-called air sandwich structure in order to prevent a decrease in sensitivity and S / N ratio.

Further, when recording / reproducing is performed by forming a recording layer containing these dyes on a substrate, normally, recording / reproducing is performed by irradiating writing light and reading light from the back surface side of the substrate.

However, when a substrate made of a transparent resin such as polycarbonate or acrylic resin is used as the substrate, the resin substrate surface is covered by the coating solvent at the time of coating the recording layer, and the reflectance of the recording layer is lowered, so that the read S There is a drawback that the / N ratio cannot be high enough.

Further, during long-term storage, dyes and other additives may be dissolved and diffused in the substrate resin, which may reduce the reflectance.

Furthermore, the writing causes damage such as the substrate being dented by heat, which also reduces the S / N ratio. In addition, noise after erasing increases.

On the other hand, the present inventors have proposed to use a coating film of a colloidal particle dispersion of a silicon-based condensate as an underlayer (Japanese Patent Laid-Open No. 60-203489).

However, the underlying layer formed by such a coating has a problem in that the adhesiveness to the substrate is not sufficient, and particularly the adhesiveness after recording and writing deteriorates.

In addition, because of the presence of such an underlayer, the tracking control grooves or pits formed on the substrate in advance and the address signal pits formed on the substrate in the tracks are filled, and the reproduction signal or the address signal is formed. There is also a problem that is difficult to detect.

II OBJECT OF THE INVENTION It is an object of the present invention to provide an optical recording medium which has good adhesiveness, especially adhesiveness after recording and writing, is excellent in solvent resistance, and can also reproduce well reproduced signals and address signals. is there.

III Disclosure of the Invention Such an object is achieved by the present invention described below.

That is, the present invention provides an optical recording medium having a recording layer of a dye or a dye composition formed by coating on a substrate by plasma-polymerizing a silicon compound having a siloxane bond between the recording layer and the substrate. An optical recording medium having a plasma polymerized film underlayer formed, wherein the plasma polymerized film has a refractive index of 1.3 to 1.7 at 6328Å.

IV Specific Configuration of the Invention Hereinafter, the specific configuration of the present invention will be described in detail.

The optical recording medium 1 of the present invention, as shown in FIG.
11 having a recording layer 12 on the recording layer 12 and a substrate
The base layer 13 is provided between the base layer 11 and the base layer 11.

It is preferable that the substrate 11 is substantially transparent (preferably 80% or more in transmittance) to writing light and reading light. If it is substantially transparent, writing and reading are performed from the back surface side of the substrate. Can be done,
It is advantageous in terms of sensitivity, S / N ratio, etc., and is also advantageous in terms of mounting such as measures against dust.

The shape of the substrate may be any of disc, tape, drum, belt, etc., depending on the intended use.

As shown in FIG. 1, it is preferable to form a pregroup 115 for tracking on the surface of the substrate 11 on which the recording layer 12 and the underlayer 13 are formed.

The groove depth of the pre-groove 115 is about λ / 8n, especially λ / 7.
n to λ / 12n (where n is the refractive index of the substrate). The width of the groove of the pre-groove 115 is about the track width.

Then, it is preferable to irradiate the writing light and the reading light from the back surface side of the substrate with the recording layer 12 located in the concave portion or the convex portion of the pre-groove 115 as a recording track portion.

With this configuration, the write sensitivity and the read S / N ratio are improved, and the tracking control signal is increased.

Instead of forming such a groove, a pit may be formed.

Further, pits for address signals can be provided in the track portion.

The formation of grooves and pits on the substrate 11 is
The 2P method or the injection molding method may be used.

The substrate 11 is usually made of resin and is made of acrylic resin, polycarbonate resin, epoxy resin, olefin resin such as polymethylpentene, or the like, but may be glass or the like.

The substrate preferably has at least a resin surface, and examples of the resin used include those mentioned above.

A base layer 13 and a recording layer 12 are formed on such a substrate 11.

The underlayer 13 in the present invention is formed of a plasma polymerized film, and the plasma polymerized film is formed by polymerizing a silicon compound having a siloxane bond.

The following compounds are preferable as the organosilicon compound having a siloxane bond.

Tetramethoxysilane, tetraethoxysilane, octamethylcyclotetrasiloxane, hexamethylcyclosiloxane, hexamethoxydisiloxane, hexaethoxydisiloxane, triethoxyvinylsilane, dimethylethoxyvinylsilane, trimethoxyvinylsilane,
Methyltrimethoxysilane, dimethoxymethylchlorosilane, dimethoxymethylsilane, trimethoxysilane,
Dimethylethoxysilane, trimethoxysilanol, hydroxymethyltrimethylsilane, methoxytrimethylsilane, dimethoxydimethylsilane, ethoxytrimethoxysilane, bis (2-chloroethoxy) methylsilane, acetoxytrimethylsilane, chloromethyldimethylethoxysilane, 2-chloroethoxytrimethyl Silane, ethoxytrimethylsilane, diethoxymethylsilane, ethyltrimethoxysilane, tris (2-chloroethoxy) silane, dimethoxymethyl-3,3,3-trifluoropropylsilane, 1-chloromethyl-2-chloroethoxytrimethylsilane , Allyloxytrimethylsilane, ethoxydimethylvinylsilane, isoprofenoxytrimethylsilane, 3-chloropropyldimethoxymethylsilane, chloro Chill DEMS, triethoxychlorosilane, 3-chloropropionyl Le pills trimethoxysilane, diethoxy dimethyl silane, dimethoxy-3-mercaptopropyl methyl silane, triethoxy silane, 3-mercaptopropyltrimethoxysilane,
3-aminopropyltrimethoxysilane, diethoxymethylvinylsilane, chloromethyltriethoxysilane,
Tertiary butoxytrimethylsilane, butyltrimethoxysilane, methyltriethoxysilane, 3- (N-
Methylaminopropyl) triethoxysilane, diethoxydivinylsilane, diethoxydiethylsilane, ethyltriethoxysilane, 2-mercaptoethyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, p-chlorophenyltriethoxysilane, phenyltrimethoxy. Silane, 2-cyanoethyltriethoxysilane, allyltriethoxysilane, 3-chloropropyltriethoxysilane, 3-allylaminopropyltrimethoxysilane, propyltriethoxysilane, hexatrimethoxysilane, 3-aminopropyltriethoxysilane, 3 -Methylacryloxypropyltrimethoxysilane, methyltris (2-methoxyethoxy) silane, diethoxymethylphenylsilane, p-chlorophenyltriethoxysila , Phenyltriethoxysilane, tetraallyloxysilane, tetrapropoxysilane, tetraisopropoxysilane, dimethoxydiphenylsilane, diethoxydiphenylsilane, tetraphenoxysilane, 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane , Octamethyltrisiloxane, 1,1,1,3,5,5,5-heptamethyltrisiloxane, hexaethylcyclotrisiloxane, 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane , Octamethylcyclotetrasiloxane, hexamethylcyclosiloxane.

These may be used alone or in combination of two or more.

In addition, the above various organic silicon compounds may be used together, or siloxane and a hydrocarbon compound may be used.

As a hydrocarbon compound, methane, ethane, propane, butane, which is a gas at ordinary temperature, is usually used because of its good operability.
One or more kinds of pentane, ethylene, propylene, butene, butadiene, acetylene, methylacetylene and other saturated or unsaturated hydrocarbons are used, and the hydrocarbon compound is usually used in a molar ratio of about 50 times or less with respect to the silicon compound. be able to.

The plasma polymerized film of the present invention has a refractive index n of 1.3 to 1.7 at 6328Å.

If the refractive index is such that n is less than 1.3, the denseness of the film is insufficient and sufficient solvent resistance cannot be obtained.
This is because the adhesiveness is not sufficient, and if it exceeds 1.7, the water repellency and hardness of the polymer film increase, and the adhesion with the recording layer 12 (coating film) that is placed in contact with the polymer film becomes poor. This is also because it is difficult to construct layers.

When such n is set, a low film formation rate and low pressure plasma polymerization conditions may be selected as described later.

In the present invention, the thickness of the plasma polymerized film underlayer 13 is
It is preferably 10 to 1000Å, preferably 50 to 600Å.

The reason why such a thickness is set is that if the thickness is less than 10 Å, the effect of the present invention cannot be obtained.

An ellipsometer or the like may be used to measure the film thickness.

The film thickness can be controlled by controlling the reaction time at the time of forming the plasma polymerized film, the flow rate of the raw material gas, and the like.

The plasma polymerized film underlayer 13 forms a polymerized film by bringing the above-mentioned discharge plasma of the source gas into contact with the substrate.

To summarize the principle of plasma polymerization, when a gas is kept at a low pressure and an electric field is applied, the free electrons present in the gas in a small amount have a much larger intermolecular distance than normal pressure, so they are subjected to electric field acceleration and 5 to 10 eV Kinetic energy (electron temperature)
To win.

When the accelerated electrons collide with atoms or molecules, they break up the atomic orbitals and molecular orbitals and dissociate them into species that are unstable in normal conditions, such as electrons, ions, and neutral radicals.

The dissociated electrons are again accelerated by the electric field to dissociate another atom or molecule, and the chain action immediately turns the gas into a highly ionized state. And this is called plasma gas.

Since gas molecules have few opportunities to collide with electrons, they do not absorb much energy and are kept at a temperature close to room temperature.

Such a system in which the kinetic energy of electrons (electron temperature) and the thermal motion of molecules (gas temperature) are separated is called low-temperature plasma, and here, chemical species or comparatively archetypes are maintained while additive processing such as polymerization is performed. A situation has been created in which a chemical reaction can proceed, and the present invention intends to utilize this situation to form a plasma polymerized film on a substrate. Since the low temperature plasma is used, there is no thermal effect on the substrate.

An example of an apparatus for forming a plasma polymerized film on the surface of a substrate is shown in FIG. FIG. 2 shows a plasma polymerization apparatus using a frequency variable power source.

In FIG. 2, raw material gas is supplied to the reaction vessel R from a raw material gas source 511 or 512 via mass flow controllers 521 and 522, respectively. Gas source 511 or 512
When different gases are supplied from the above, they are mixed and supplied in the mixer 53.

The raw material gas may have a flow rate range of 1 to 250 ml / min.

In the reaction container R, the substrate 111 to be processed is supported by one rotary electrode 552.

Then, an electrode 551 facing the rotary electrode 552 is provided so as to sandwich the substrate 111 to be processed.

One electrode 551 is connected to, for example, a variable frequency power source 54, and the other rotary electrode 552 is grounded at 8.

Further, in the reaction vessel R, a vacuum system for exhausting the inside of the vessel is provided, and this includes an oil rotary pump 56, a liquid nitrogen trap 57, an oil diffusion pump 58 and a vacuum controller 59. These vacuum systems have 0.1 Tor in the reaction vessel.
It is maintained in a vacuum degree range of less than r, preferably 0.005 to 0.08 Torr.

In the operation, first, the inside of the reaction vessel R is evacuated to 10 ^-5 Torr or less, and then the processing gas is supplied in a mixed state into the vessel at a predetermined flow rate.

The film formation rate is preferably 50 to 200 Å / min in the case of the above-mentioned n polymer film.

At this time, the degree of vacuum in the reaction vessel is controlled to be less than 0.1 Torr, preferably 0.005 to 0.08 Torr.

When the flow rate of the raw material gas becomes stable, the power is turned on.
In this way, the polymerized film is formed on the plasma on the substrate.

Note that Ar, N ₂ , He, H ₂ or the like may be used as the carrier gas.

Further, the applied current, the processing time, etc. may be set under normal conditions.

As the plasma generation source, any of microwave discharge, direct current discharge, alternating current discharge and the like can be used in addition to high frequency discharge.

In the present invention, it is preferable to use the magnetron system in which a magnetic field is used in combination, especially when the operating pressure is low.

When a liquid monomer is used as a raw material in the present invention, a container containing the liquid monomer at the gas sources 511 and 512 in FIG. 2 may be installed in a constant temperature bath for use.

The Si content in the plasma polymerized film of the magneto-optical recording medium of the present invention thus formed is usually 2 to 95 at%, especially 2 to 95 at%.
It is about 80 at%.

Further, it is preferable that the C content in the plasma polymerized film is about 5 to 50 at%, and the H content is about 5 to 90 at%.

The O content in the plasma polymerized film is usually about 40 at% or less.

The content of Si, C, H and other elements in the plasma polymerized film may be analyzed according to SIMS (secondary ion mass spectrometry) or the like. When SIMS is used, it may be calculated by counting Si, C, H and other elements on the surface of the plasma polymerized film.

Alternatively, while performing ion etching with Ar etc., S
It may be calculated by measuring profiles of i, C, H and other elements.

Regarding the measurement of SIMS, Surface Science Basic Course Vol. 3 (19
84) Basics and applications of surface analysis (p70) "SIMS and LAMMA"
You can follow the description.

Such a plasma polymerized film underlayer 13 is preferably formed on the plasma-treated substrate 11.

By subjecting the surface of the substrate 11 to plasma treatment, the substrate 11
The adhesive force between the substrate and the plasma polymerized film underlayer 13 is improved.

The principle of the plasma treatment method on the surface of the substrate 11, the method, the forming conditions and the like are basically the same as those of the plasma polymerization method described above.

However, in the plasma processing, in principle, an inorganic gas is used as a processing gas (in some cases, an inorganic gas may be mixed) as a source gas.

The plasma processing gas of the present invention is not particularly limited.

_{That, H 2, Ar, He,} O 2, N 2, _{air, NH 3, O 3, H} 2 O; NO, N 2 O,
These may be selected from NOx such as O ₂ and the like, and these may be used alone or in a mixture.

Further, the frequency of the plasma processing power source is not particularly limited, and may be DC, AC microwave or the like.

The recording layer 12 may be of various types. However,
In the present invention, it is preferable that the dye is used alone or the dye composition is used.

The dye to be used may be appropriately determined from those that effectively absorb the wavelengths of the writing light and the reading light. In this case, as these light sources,
Since it is preferable to use a semiconductor laser from the viewpoint that the device can be downsized, the dye is preferably cyanine, phthalocyanine, anthraquinone, azo, triphenylmethane, pyrylium or thiapyrylium salt.

When the dye composition is used as the recording layer, a self-oxidizing resin such as nitrocellulose or a thermoplastic resin such as polystyrene or nylon can be contained. Further, in order to prevent oxidative deterioration of the dye, a quencher may be contained. Further, other additives may be contained.

In such a case, a mixture of an indolenine type cyanine dye and a bisphenyldithiol type quencher is particularly preferable.

It is also preferable to use these as an ionic bond between the cation of the dye and the anion of the quencher.

For details of preferred dyes and quenchers, see JP-A-59-55794, 59-55795, 59-81194 and 5
9-83695, 60-18387, 60-19586, 60-19
587, 60-35054, 60-36190, 60-36191
No. 60, No. 60-44554, No. 60-44555, No. 60-44389,
60-44390, 60-47069, 60-20991, 60
-71294, 60-54892, 60-71295, 60-712
96, 60-73891, 60-73892, 60-73893
No. 60, No. 60-83892, No. 60-85449, No. 60-92893,
60-159087, 60-162691, 60-203488, and
60-201988, 60-234886, 60-234892, 61
-16894, 61-11292, 61-11294, 61-168
No. 91, No. 61-8384, No. 61-14988, No. 61-163243
No. 61-210539, Japanese Patent Application No. 60-54013, and the like.

The recording layer 12 may be applied by spinner coating or the like using a solvent such as a ketone type, an ester type, an ether type, an aromatic type, an alkyl halide type, or an alcohol type. In the present invention, since the underlayer 13 is provided, the solvent resistance is improved, and the optimum solvent can be used by selecting it from a wide range of solvents.

Such a recording layer 12 may have a thickness of 0.01 to 10 μm.

When a groove or pit for tracking control is provided, the thickness of the recording layer is preferably 0.2 μm or less, more preferably 0.05 to 0.15 μm.

At this time, the writing sensitivity is improved. Also, due to multiple reflections in the recording layer, the reflectivity becomes extremely high, and the S / N ratio for reading becomes extremely high. Then, the difference in reflectance due to the difference in thickness between the recording track portion and other regions becomes large, and tracking control becomes easy.

An upper layer of the recording layer may be provided in such a recording portion.

Further, the optical recording medium of the present invention may be provided with a protective plate.

It is preferable that the substrate 11 having the underlayer 13 and the recording layer 12 and the protective plate are integrated with each other through a gap, and in that case, a protrusion may be provided on one side to integrate them. Sonic fusing may be used.

In the case of ultrasonic welding, if the projection is made into a rod shape, for example, the projection is effectively heated, the fusion efficiency is good, the workability is good, the adhesive strength is high, and the gap spacing is also accurately controlled. can do.

When the deformation is large and the protrusion arrangement density is high, an airtight outer peripheral wall may be formed on the entire surface.

 Vents can also be formed between the partitions.

 The vent hole is formed in the gap between the protrusions.

Fixing is also performed by injecting an adhesive.

Alternatively, a hot-melt resin may be applied as an adhesive to the peripheral portion of the substrate, and then both substrates may be combined and ultrasonically fused, that is, a combination of so-called adhesion and fusion may be used for integration.

In order to form such a plurality of rod-shaped protrusions, a master or a stamper may be processed and integrally molded at the time of molding a substrate.

Although the integration using the rod-shaped projections has been described above, various other known integrated structures are possible.

Although the case of single-sided recording has been described above, the present invention may be a double-sided recording medium in which recording layers are provided on both substrates. In this case, it is necessary that both substrates are made of a substantially transparent resin, and both substrates are provided with a base layer.

V Specific Action of the Invention The optical recording medium of the present invention is a normal disc,
The writing light is emitted from the back side of the substrate. As a result, pits are preferably formed in a track shape in the recording track portion located in the groove recess.

The pits thus formed are detected by irradiating the reading light from the back surface side of the substrate while rotating and detecting the reflected light.

In order to control tracking, the reflected light is usually divided while writing and reading, and is introduced into a pair of two divided sensors. At this time,
When the beam spot deviates from the recording track portion, the primary light due to the interference effect due to the phase difference due to the step difference of the groove is deflected toward one sensor side, so that the signals of both sensors are detected and the track error signal is detected.

Note that the pits once formed in the recording layer can be erased by light or heat and writing can be performed again.

As a light source used for writing and reading, various lasers can be used, but a semiconductor laser is particularly preferable.

VI Specific Effect of the Invention The optical recording medium of the present invention has a recording layer of a dye or a dye composition on a substrate, and a silicon compound having a siloxane bond is polymerized between the recording layer and the substrate. Since it has a plasma polymerized film underlayer formed by
Adhesiveness, particularly adhesiveness after recording and writing, is good, excellent solvent resistance, high reflection level, and good reproduction signal can be obtained. Furthermore, it is possible to prevent burying of the tracking control groove or pit and the address signal pit, and there is no error signal generation due to the tracking control groove or pit burial, and there is no address signal pit burial. The address signal can be reproduced well.

VII Specific Examples of the Invention Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention.

Example A substrate 11 made of a bisphenol A-based polycarbonate resin (molecular weight: 15000) having a diameter of 13 cm and a thickness of 1.2 mm was injection-molded into a spiral groove having a width of 0.6 μm and a depth of 0.1 μm for tracking control. Pits for address signals of 0.6 μm and depth of 0.1 μm were provided respectively. Such a substrate 11 is put in a vacuum chamber and once
After drawing a vacuum of ^-5 Torr, Ar is used as a processing gas, and a high frequency voltage of 13.56 MHz is applied to generate plasma while maintaining a gas pressure of 0.1 Torr at a flow rate of 50 ml / min, and the surface of the substrate 11 is plasma-treated. did.

Then, a plasma polymerized film underlayer 13 was further formed on the substrate 11 under the conditions shown in Table 1.

The refractive index n shown in Table 1 was measured at 6238Å.

The elemental analysis of these plasma polymerized films was measured by SIMS, and the film thickness was measured by an ellipsometer.

The recording layer 12 is an indolenine cyanine dye (1,3,3,1 ′,
3 ', 3'-Hexatrimethylindotricarbocyanine cation) and a bisphenyldithiol system quencher (bis (trichlorophenyldithiol) Ni anion)
A 2.2% cyclohexanone solution of the dye conjugate of and was applied and applied onto the substrate 11 on which the underlayer 13 was applied to a thickness of 0.05 μm as described above.

 In this way, samples 1 to 8 were obtained.

A sample having no underlying layer was also prepared and used as Sample 10.

For comparison, a sample using a coating film of a colloidal particle dispersion liquid (colcoat) of a silicon-based condensate disclosed in JP-A-60-203489 as an underlayer was prepared, and this was designated as Sample 11.

In this case, the underlayer contains ethyl acetate and ethyl alcohol.
Mix at a ratio of 10:11 and gradually add Si (OC ₂ H ₅ ) while stirring.
After the addition ₄ at a ratio of 2/25 to ethyl acetate, allowed to stand solution for 3-4 days was diluted further 10 times with n- propanol, and coating laying layer on a substrate, 60 ° C., and treated for 30 minutes Formed.

The particle size of the silicon oxide colloid is 50-80Å,
The thickness of the underlayer was 400Å.

 The following measurements were performed using the above samples.

(1) Adhesive strength between substrate and underlayer The adhesive strength of each sample at the beginning, after recording, and after being left for 10 days in an atmosphere of 60 ° C, 90% RH, crosses each sample at 1 mm intervals in 11 rows and 11 rows each. It was evaluated by the residual rate (%) on the substrate when cut and subjected to a peeling test with a cellophane tape.

The recording was performed at a recording power of 3.8 mW and a linear velocity of 1.3 m / S.

(2) Reflection level At 830 nm, the reflection level was measured from the back surface side of the substrate while the groove portion was tracking-controlled by the optical disk drive device. The values in the table are in arbitrary units.

(3) Amount of tracking error signal Recording film surface (unrecorded portion) in the optical disk drive device
The amount of push-pull tracking error signal was measured in the state where the light was focused on and the tracking control was not performed. It is an arbitrary unit in the table.

(4) Reproduction of Address Signal The amount of address signal light was measured while tracking control was performed by focusing light on the recording film surface (address signal portion) with an optical disk drive device. The values in the table are in arbitrary units.

 Table 2 shows the results.

From the results in Table 2, the effect of the present invention is clear. That is, even if the refractive index n of the plasma polymerized film is less than 1.3
Even if it exceeds 1.7, the adhesiveness, particularly the adhesiveness after recording and storage, is deteriorated and the reproduction characteristics are deteriorated. Further, the effect of the present invention cannot be obtained with a coating film.

[Brief description of drawings]

FIG. 1 is a sectional view showing one embodiment of the optical recording medium of the present invention. FIG. 2 is a schematic diagram of a plasma polymerization apparatus. Explanation of symbols 1 ... Optical recording medium, 11 ... Substrate, 115 ... Groove, 12 ... Recording layer, 13 ... Plasma polymerized film underlayer, 53 ... Mixer, 54 ... DC, AC and variable frequency Type power source, 56 …… Oil rotary pump, 57 …… Liquid nitrogen trap, 58 …… Oil diffusion pump, 59 …… Vacuum controller, 111 …… Substrate to be processed, 511,512 …… Source gas source, 521,522… … Mass flow controller, 551,552 …… Electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masatoshi Nakayama 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (56) References JP-A-61-184743 (JP, A)

Claims (3)

(57) [Claims] 1. An optical recording medium having a recording layer of a dye or a dye composition formed by coating on a substrate, formed by plasma polymerizing a silicon compound having a siloxane bond between the recording layer and the substrate. An optical recording medium having the above-mentioned plasma polymerized film underlayer, wherein the refractive index of the plasma polymerized film at 6328Å is 1.3 to 1.7. 2. The thickness of the underlayer of the plasma polymerized film is 10 to 1000Å
The optical recording medium according to claim 1, wherein 3. The optical recording medium according to claim 1 or 2, wherein the substrate has at least a resin surface.