JPS6275946A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To improve the adhesiveness between a light transmittable resin substrate and recording layer without spoiling the shape of guide grooves by interposing a light transmittable adhesive layer contg. fluoroplastic between the light transmittable substrate and the recording layer. CONSTITUTION:The recording layer 3 is formed via the adhesive layer 2 which contains the fluoroplastic and has light transmittability on the light transmittable resin substrate 1 formed with the guide grooves. An interference layer 4 and a light reflective layer 5 are successively formed on the layer 3. The adhesiveness between the substrate 1 and the layer 3 is improved without spoiling the guide grooves formed on the surface of the substrate 1 and the exfoliation of the layer 3 exposed to a high temp. and high humidity is obviated by using the layer 2, by which the long-term reliability is improved.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an optical information recording medium that records and reproduces information by illuminating a light beam such as a laser beam, and particularly relates to an optical information recording medium that records and reproduces information using a light beam such as a laser beam. The present invention relates to an optical information recording medium formed by forming a recording layer thereon.

[Problems with technical backbone of inventions]

An optical information recording medium, a so-called optical disk, records and reproduces information by illuminating a light beam 11 emitted from a semiconductor laser or the like. ), so the recording density is extremely high and it is possible to make a large number of records.

(2 Information is recorded and reproduced without contact, so there is no wear on the medium.

(3) Fast access of several hundred glSeC or less is possible. Because of these advantages, it is highly anticipated as the next generation peripheral memory.

Such optical discs basically consist of a disc-shaped substrate,
It is composed of a recording layer that undergoes some kind of optical change when irradiated with a light beam. Here, as for the optical change of the recording layer.

(a) The light beam irradiation part undergoes deformation (formation of bits or bubbles), and the light reflectance of the deformed part changes.

(b) The light beam irradiation section causes a phase change, and the light reflectance of the phase change section changes.

(C) The magnetization of the light beam irradiation section is reversed, and the polarization state of the magnetization reversal section is changed.

Examples of such phenomena include:

For optical discs that utilize any of these optical changes, a practical method is to irradiate a recording layer with a recording/reproducing light beam through a substrate.

This is because dirt and dust adhere to the exposed side of the recording layer, so writing and reading errors increase when the light beam is irradiated from the exposed side, whereas the disk manufacturer If you are careful enough, you can prevent dust from landing on the substrate, and since the light beam is defocused on the side of the substrate opposite to the recording layer, dust adhering to this side can cause errors. This is due to two reasons: work.

In the case of this method of irradiating a light beam through a substrate, the substrate of the optical disk is naturally required to be translucent (transparent), and in order to lower the noise level, the birefringence is as high as possible. In addition, in order to quickly move the optical head to a predetermined position on the disk surface and achieve high-speed access, a group of guide grooves (guide grooves) for guiding the optical head is required. ) is required, but
It is much more advantageous from the standpoint of recording layer forming technology to provide this guide groove in advance on the substrate surface than to provide it in the recording layer.

These three basic requirements (translucency, low birefringence).

The M plate materials that simultaneously satisfy the moldability of the guide groove are polymethyl methacrylate and polycarbony.

This is a transparent resin substrate typically made of epoxy or the like.

However, since such transparent resin materials have extremely poor adhesion to inorganic materials, it is difficult to form a recording layer made of a metal or metal compound on a transparent resin substrate with good adhesion. She is extremely troublesome. For example, at present, a rare earth-transition metal amorphous ferrimagnetic film (hereinafter referred to as RE-
RE-TM films) also have poor adhesion to translucent resin substrates, and this is one of the reasons for delaying the commercialization of optical disks (also called magneto-optical disks) that use RE-TM films as recording layers. There is.

In order to solve this problem, an optical disc in which an adhesive layer is interposed between the substrate and the recording layer has been proposed, as described in Japanese Patent Laid-Open No. 60-79534.

In this known example, the adhesive layer is formed using a spin code method.
is formed. However, such wet
When an adhesive layer is formed in a process, there is a problem that the adhesive layer distorts the shape of the guide groove, impairing important functions in optical discs such as tracking, focusing, and random access.

[Purpose of the invention]

The present invention has been made in view of the problems of the prior art described above.
An object of the present invention is to provide an optical information recording medium that can improve the adhesion between a transparent resin substrate and a recording layer without damaging the shape of the guide groove.

[Summary of the invention]

To achieve this object, the present invention is characterized in that a light-transmitting adhesive layer containing fluorocarbon resin is interposed between the light-transmitting resin substrate and the recording layer.

Polymethyl methacrylate, polycarbonate, epoxy, etc. are used as the material for the translucent resin substrate, and the recording layer is made of polymethyl methacrylate, polycarbonate, epoxy, etc. ) Metals (for example, RE-1'M films, shape memory alloys, etc.), semiconductors, metal oxides, etc. that cause optical changes due to 1 are used.

The adhesive layer is made of 3i3N4゜ANN in addition to fluorocarbon resin.
, S i 02 , zns, CaF2. r TO.

J: Yes, even those containing translucent inorganic materials such as BN.

In that case, the mixing ratio X of the fluorinated resin in the adhesive layer may be uniform in the thickness direction, but compared to the averaged value in the thickness direction, ＞X
, on the side closer to the recording layer, it is more desirable that the thickness changes in the thickness direction so that it becomes X<or> from the viewpoint of improving reliability due to the adhesion layer.

(Invention ν) Song Dynasty) According to the present invention, the problem of adhesion between the substrate and the recording layer when a resin substrate is used is solved by using a light-transmitting adhesive layer containing fluorocarbon resin. , high temperature and high humidity F1. : An optical information recording medium with long-term reliability that does not cause peeling of the recording layer even after being left unused can be obtained.

In addition, the adhesive layer mainly composed of fluorine resin used in the present invention has light transmittance and weather resistance.

Not only does it have excellent film formation properties, but it can also be formed using dry processes such as sputtering and plasma polymerization, allowing the fine guide grooves formed on the substrate to be reflected correctly on the recording layer without damaging their shape. Is possible. Therefore, there is an advantage that various controls such as one-racking, focusing, and one-way access using the guide groove can be performed stably.

[Embodiments of the invention]

The present invention will be explained in detail below. FIG. 1 is a cross-sectional view of an optical information recording medium (hereinafter referred to as an optical disk) according to an embodiment of the present invention, in which a transparent adhesive layer 2 containing fluorocarbon resin is formed on a transparent resin substrate 1. A recording layer 3 is formed therebetween, and an interference layer 4 and a light reflection layer 5 are further formed in this order on the recording layer 3.

As the transparent resin substrate 1, for example, a polycarbonate substrate is used, and guide grooves are formed on the surface thereof. The adhesive layer 2 contains, for example, tetrafluoroethylene as a fluorocarbon resin. The recording layer 3 is, for example, T
It consists of RE-7M membrane like bC0 membrane. For example, a 3i3N+ film is used for the interference layer 4, and an AR film is used for the light anti-layer 5.

FIG. 2 shows an example of the configuration of a sputtering apparatus used for manufacturing this optical disk, in which 11 is a sputtering chamber, 12 is a substrate holder that holds the transparent resin substrate 1 shown in FIG. 1, and 13 is a rotation of the substrate holder 12. jig, 14 is an RF power supply, 15 is a magnet], a sputter source for Ron sputtering, 16 is a power supply for sputtering, 17 is a shutter, 18 is a seal l: members, one is a sputtering gas supply system, 20 is an exhaust system, Reference numeral 21 denotes a board installation jig.

Hereinafter, specific embodiments of the optical disc manufacturing process according to the present invention will be described.

<Example 1> Using the sputtering apparatus shown in FIG. 2, an optical disk having the structure shown in FIG. 1 was manufactured in the following procedure. The transparent resin substrate 1 is φ120. , 1°2 mt polycarbonate substrate with guide grooves was prepared. This was obtained by manufacturing a stamper from a master disk obtained by exposing and developing a photopolymer with an Ar ion laser, and injection molding a polycarbonate resin using this stamper. This substrate was subjected to ultrasonic cleaning for 5 minutes in a neutral detergent solution, washed with pure water, N2 blow drying, and desiccator drying, and then placed in the sputtering chamber 11 and screwed to the substrate holder 12. . Process the jig 21 to seal the sputtering chamber 11, operate the exhaust system 20 to exhaust the pressure inside the sputtering chamber 11 to 5X10-6 Torr, and open the gas supply system 1.
Ar gas with a purity of 99.9<19% is supplied from 9, and the gas pressure in the sputtering chamber 11 is set to 5x 10-3 Torr k.
: mutually agreed. Next, the substrate holder 12 is rotated at 60 rpm using the jig 13, and with one of the shutters 17 closed, the sputter source 15 (5 inch diameter
・It stores Lafluoroethylene Targera)
An RF power of 150 W was applied from the power source 16 to. After performing pre-sputtering (sputtering with the shutter 17 closed) for 5 minutes and cleaning the target surface, the shutter 11 was opened as described above, and sputtering was performed for about 20 minutes. After turning off the sputtering chamber 11 and restoring the inside of the sputtering chamber 11, the jig 21 is raised,
The substrate 1 on which the adhesive layer 2 made of tetrafluoroethylene was formed was taken out.

At the same time, we evaluated the film quality of the adhesive layer 2 formed by the above method using small pieces of polycarbonate and epoxy (approximately 151 MX 25 am) on glass, polymethyl methacrylate 1 installed on the substrate holder 12, and found that the thickness was - 10= is 10 (10 people, light transmittance is 93% (wavelength 830n)
n+, polymethyl methacrylate 1 no i ~ substrate), chemical resistance is good to the extent that there is no deterioration after 30 minutes of ultrasonic cleaning in aretone, and adhesion to the substrate is confirmed by beer-off test using adhesive tape. .

Polycarbonate, epoxy, and glass are strong enough to not peel off from the substrate, and can withstand 65℃ - 90%
R, l-1, high 1 high humidity atmosphere 241-1 rs.

←→IHr under room temperature atmosphere, cycle accelerated deterioration test 4
Even after bonding for 4 cycles, no peeling occurred from any of the four types of substrates described above, and there was no deterioration (change in light transmittance) of the TE1-RAfluoroethylene film itself.

On the other hand, in Comparative Example 1 (2), a 513N4 underlayer was formed in place of the adhesive layer 2. The sputtering gas is N2- with a partial pressure of 3% N2.
The Ar mixed gas was used, the power input to the 3i target 1- was 300 W, and the film forming time was 20 minutes. The 5isN4 base layer obtained by J: was evaluated in the same manner as the adhesive layer made of the above-mentioned tetrafluoroethylene film, and the film thickness was 1.
000 people, light transmittance 91%, acetone ultrasonic cleaning 30
There is no deterioration in quality within minutes, and the adhesion to the substrate does not peel off only in the case of glass substrates, and other polymethylmethacrylate-1.
.

It can be easily removed from resin substrates such as polyimide and epoxy, and it can also be used in the same one-cycle accelerated deterioration test as above.
After continuing the cycle, 5i is required only for glass substrates.
There was no peeling of the aN4 base layer, and the Si3N on the curved resin substrate
+ Base layer (i) Local peeling (wrinkles with a width of about 10t1m near the film surface) occurred in both cases, and the light transmittance decreased due to this peeling.

Next, each of the four sputters 8115 in FIG.
Set targets for i, -rb, Go, and An, and
Recording H3 made of bCo film, interference layer 4 made of S ia N4 film. and the formation of the light reflecting layer 5 made of AQ film,
a polycarbonate substrate on which the adhesive layer 2 is formed;
Polycarbonate 1 to substrate- on which 3i3N+ underlayers were formed as comparative examples were tested in the same batch. These two types of substrates are screwed to the substrate holder 12, the jig 21 is processed, the inside of the sputtering chamber 11 is evacuated to 5 x 10" 6 Torr by the exhaust system 20, and the gas supply system 19
After introducing Ar gas with a purity of 99,990% and maintaining the gas pressure in the sputtering chamber 11 at 5x 10-' Torr, the RF'1ai 14 was turned on and the substrate surface was
Cleaning was performed by sputter etching at 0W RF power for 5 minutes.

Next, sputter source 1 for Tb target and co target
With the shutter 17 corresponding to No. 5 closed, DC power was supplied from the power source 16 to the sputtering sources 15 of both targets to give a voltage of 0.5 A to the Tb target.

After cleaning the surface of each target by applying a discharge current of 1.5 A to the Co targets 1 to 1 to perform press sputtering for 5 minutes, the substrate holder 12 was rotated at 6° rpm by the jig 13, and the Tb target, Co target]. The shutters 17 corresponding to the sputtering sources 15 were simultaneously opened to form a TbCo film for 35 seconds, and a TbCo film of about 250 nat.
A recording layer 3 made of a C0 film is formed, and! I turned off 1t116.

Next, the gas was changed to a N2-Ar mixture with a 3% partial pressure of N2, and 300 W of RF power was applied from the power source 16 to sputtering #i15 on the S1 target 1. After press sputtering was performed for 5 minutes, the sputtering was performed. Film formation was performed for 5 minutes, and recording layer 3 was formed.
About 250 nats of Si3N+Il on top! An interference layer 4 was formed.

Next, the gas was changed to lllAr gas, and 300 W of RF power was applied from an electric m16 to the sputtering target 1I115, and after press sputtering for 5 minutes, sputtering was performed for 10 minutes to form a film on the interference layer 4 made of 5i3Nnllll. A light reflecting layer 5 made of an Affi film is formed to a thickness of about 1000 mm, the electric WA 16 is turned off, the rotation of the substrate 1 is stopped, the sputtering chamber 11 is returned to the atmosphere, and the substrate 1 is raised using a jig 21. Then, the optical disc shown in FIG. 1 was taken out.

On the other hand, glass, polymethyl methacrylate 1, polycarbonate, etc., having an adhesive layer made of a 1000-layer thick Natrafluoroethylene film were installed on the substrate holder 12 at the same time.
We evaluated the performance immediately after deposition using each piece of epoxy and a similar piece with a 1000-layer thickness of Nato 3N4. Measured light reflectance "Kuo": Reflector rotation angle θ is polymethyl methacrylic L No. 1-substrate.
The sample with a tetrafluoro T tyrene adhesion layer on L is R-20%.

θk, -0,45 (18!+, also 5tiN + layer with adhesive layer)/Pull is R-25%, θk = 0.45
It was confirmed that a sufficient regeneration performance index (RX Ok product) can be obtained even in a structure having a dense layer of tetrafluoro T ethylene with 32 layers.

In addition, the strength of the beer-off test using adhesive tape was
Glass, polymethyl methacrylate.

No delamination occurred for any of the polycarbonate epoxies, whereas all samples with Si3N4 underlayers delaminated except for those on the glass substrate. In addition, these small pieces and the optical disk using the above-mentioned φ120M polycarbonate substrate with guide grooves were heated at 65°C and 90%R.
, H, 24) -1rs, ←-+ always 11 II +', →
An accelerated aging test of 65°C, 90% R, H, 481-1rs was conducted to check for peeling. Figure 3 shows the surface condition of the optical disk according to the present invention after this accelerated aging test This is a microscopic fHM photograph of 1 weave, (a) at 10x magnification, (b) at 1000x magnification. No peeling is observed at all through the surface where there is no guide groove (striped part). On the other hand, Si3N
+ In conventional optical discs having an underlayer, a phenomenon in which the film peels off from the substrate due to accelerated deterioration has been observed. Also, the third
From the micrograph shown in the figure, it is also clear that in the optical disc according to the present invention, the shape of the guide groove is well maintained without wilting.

<Example 2> In Example 1, the tetrafluoroethylene adhesion layer was formed by a sputtering method, but the de1-rough1]-roethylene adhesion layer can also be obtained by plasma polymerization of Freon gas. FIG. 4 is a diagram showing an example of the configuration of a plasma polymerization apparatus used to form a fluoroethylene adhesive layer. In FIG. 4, 41 is a polymerization chamber, and 42 is a substrate holder, which holds a resin substrate 1 (eg, polymethyl metarelay) and a substrate (φ120, with a guide groove). 43 is a coil, 44 is an RFiim, 45 is a gas supply system, and 46 is an exhaust system.

Using this plasma polymerization apparatus, a liter trough []-]loethylene was formed in the following two F areas.

First, the polymerization chamber 41 is evacuated to 5x10-6 Torr by the exhaust system 46, and then the gas supply system 71
5 to 10 sec of CF4 gas, 1 of Ar gas
0105e at the same time, turn on the RF power [44], supply 200 W of RF power to the coil 43, excite the CF4-Ar mixed gas plasma in the polymerization chamber 41, and perform plasma polymerization on the substrate 1''. The film was formed for 30 minutes and then taken out. The film quality of this plasma-polymerized tetrafluoroethylene film was slightly inferior to that of sputtered tetrafluoroethylene in terms of chemical resistance, but was otherwise as good as the sputtered tetrafluoroethylene film.

Further, TbcO
A recording layer made of S, an interference layer made of Si3N+ film, and a light reflection layer made of Ag film were sequentially formed and subjected to an accelerated deterioration test in the same manner as in Example 1. No peeling of the films occurred.
Further, no deterioration of the guide groove shape was observed.

<Example 3> In Examples 1 and 2, the case where the adhesive layer was formed only with fluorocarbon resin (Tei-Rafluoroethylene) was explained. It may contain an inorganic material having properties. Examples thereof are shown below.

A polycarbonate substrate with guide grooves similar to that in Example 1 was prepared as the translucent resin substrate 1, subjected to ultrasonic cleaning for 5 minutes in a neutral detergent solution, washed with pure water, dried with N2 blow drying, and dried in a desiccator. After that, it was put into the sputtering chamber 11 and screwed to the substrate boulder 12. Process the jig 21 to seal the sputtering chamber 11, and operate the exhaust system 20 to reduce the pressure inside the sputtering chamber 11 to 5x10-6 Torr.
After exhausting the air to
2-Ar gas was supplied to maintain the gas pressure in the sputtering chamber 11 at 5×10 −3 Torr.

Next, the substrate holder 12 is set to 6or by i/'1613.
With the two shutters 1/17 closed, the sputtering source 15 (5 inch φ
150 W and 120 W, respectively, from the power supply 16 to the tetraflow day Ethylene Targera 1 ~ and S1 targets (7) RF) - 'Fr
applied. After performing pre-sputtering (sputtering with the shutter 17 closed) for 5 minutes and cleaning the target surface, the two shutters 17 are opened, sputtering film formation is performed for about 10 minutes, and the power supply 16 is turned off. state,
After returning the inside of the sputtering chamber 11 to the atmosphere, the jig 21 is raised and the trough flow port ethylene 75vol. %-3i
The substrate 1 on which the adhesive layer 2 made of 25% of N4 was formed was taken out. At the same time, glass, polymethyl methacrylate 1-, polycarbonate 1-, etc. were placed on the substrate holder 12. The film quality of the adhesive layer 2 formed by the above method using each small piece of epoxy (approximately 15 IH x 25 g) was evaluated.The film thickness was 1000, and the light transmittance was 91% (wavelength
0 nm, polymethyl methacrylate substrate), chemical resistance is good to the extent that no deterioration occurred after 30 minutes of ultrasonic cleaning in an acetic acid bath, and adhesion to the substrate was confirmed by a beer-off test using adhesive tape. Le-1.

Polycarbonate, Epo 4, and glass are strong enough to not peel off from the substrate, and can be roughly heated to 65℃-90℃.
%R, t1. 2411rs under a high temperature and high humidity atmosphere.

←→Even after 4 cycles of 1l-1r cycle accelerated deterioration test in a constantly wet atmosphere, there was no peeling from any of the four types of substrates mentioned above, and there was no deterioration of the tetrafluoroethylene film itself (photo-induced deterioration). There was also no change in transmittance.

As described above, in the present invention, when the adhesion layer is made of a mixture of a fluorine resin and an inorganic material, almost the same effectiveness as in the case of a single fluorine resin can be obtained.

<Example 4> In Example 3, Te] - Rafloro T Chi [Non and Si3N<
We have explained the case where the mixing ratio of tetrafluoroethylene in the adhesion layer consisting of a mixture of J: It has been found that the reliability of the adhesion layer made of the eel mixture is improved by varying the mixing ratio of the fluorocarbon resin in the thickness direction of the adhesion layer. In this case, the mixing ratio X of the fluorocarbon resin is changed to a value obtained by averaging X in the thickness direction in order to bring the difference in thermal expansion coefficient and water absorption expansion coefficient between the adhesive layer, the substrate, and the recording layer as close as possible. For k, it is appropriate to set J such that x> on the side closer to the substrate and x<x on the side closer to the recording layer.

Figure 5 shows the method of forming the adhesion layer by changing the mixing ratio of the fluorine resin in the thickness direction. This is a method that changes the

For example, in the sputtering apparatus shown in FIG. 2, the adhesion layer having a change in mixing ratio as shown in FIGS. 5(a) and 5(b) can be formed by
It can be formed by temporally changing the input power ratio to the i-targets 1 to 1. Example 3
Similarly, TbCo! l! A recording layer consisting of Si3N+
An optical disk was manufactured in which an interference layer of 1 m thick and a light reflective layer of 2 l-Al1 film were sequentially laminated. ]・Raflo〇 80℃-90%R6) 1.2 with an optical disk having an adhesive layer made of a mixture of ethylene and 5iaN+
41-(rs, ←→ regular m I Hr, 4 It cycle →
The sample was subjected to an accelerated deterioration test at 80° C.-90% R0H096) 1rs under conditions more severe than those in Example 3.

FIGS. 6 and 7 are photographs of the metal structure showing the surface condition of the optical disk after this accelerated deterioration test. Figure 6 (a
) shows the surface condition of an optical disc having an adhesive layer with a step-like mixture ratio change as shown in FIG. 5(a), and FIG.
Figure 7(b) shows the surface state of an optical disc having an adhesive layer with a gradient-like mixture ratio change, and Figures 7(a) and 7(b) show an optical disc with a tetrafluoroethylene mixture ratio of 75 vol and an adhesive layer with a uniform percentage. This is the surface condition of the optical disc, and the sixth
Figures (a) and (b) and Figure 7 (a) 1. magnification 10
The magnification in FIG. 7(b) is 1000 times.

4ji adhesion layer with uniform tetrafluoroethylene mixing ratio
The optical disc was heated at 65°C - 90% as in Example 3.
R, i1. In the recycle accelerated deterioration test under the conditions below, no peeling was observed over the entire surface of the disk, but in the longer recycle accelerated deterioration test conducted in Example 4 at 80°C and 90% R, H, no peeling was observed. It is clear from FIG. 7 (a>(b)) that stripe-like peeling occurs locally.A similar phenomenon was observed in the case of the optical disk in which the adhesive layer made of tetrafluoroethylene alone was formed as described in Example 1. It was also observed in

On the other hand, in an optical disc having an adhesive layer with a step-like mixture ratio change, the J: sea urchin peeling shown in Fig. 6(a) occurs only in a very small part of the surface without guide grooves. Furthermore, it has been found that in the case of an optical disk having an adhesive layer having a gradient-like mixture ratio change, no peeling occurs at all, as shown in FIG. 6(b). Therefore, in environments such as offices, even an adhesive layer with a uniform mixing ratio can be expected to be highly reliable, but when storing optical discs for long periods of time in harsh environments, The adhesion layer in which the mixing ratio of fluorocarbon resin is changed in the thickness direction is better.
Higher reliability can be obtained.

In addition, when forming an adhesion layer having a step-like change in the mixing ratio as shown in FIG. teeth,
CF for the 100% ethylene layer
It can also be formed by a plasma polymerization method using four gases. A layer of a mixture of tetrafluoroethylene and an inorganic material can also be formed by simultaneous plasma polymerization of CF4 gas and sputtering of a non-IJl material target, but the manufacturing conditions are difficult. Simultaneous sputtering of a single flow one-shot ethylene target and an inorganic material target is preferred.

The present invention can further take on various embodiments as described below. For example, in the above embodiments, a T b Co film that utilizes the magneto-optical effect was used as the recording layer, but other RE-TMIlls may be used, and RE-
The adhesion layer according to the present invention can also be applied to optical discs having a recording layer other than a TM film, such as a CLI A ff film that utilizes a shape memory effect, and an optical disc that has a recording layer of a 5eTe film, an InSb film, etc. that utilizes a change in crystal structure. can be applied, and the same effects as in the previous embodiment can be expected.

Further, in Example 3, Si3N+ was shown as a translucent inorganic material to be mixed with fluorocarbon resin (tetrafluoroethylene), but inorganic materials other than 3i3N4, such as Si0
2, S i O, AffiN, ZnS.

CaF2. A similar effect can be obtained by using rTO or the like. In fact, using targets made of these inorganic materials, sputtering was performed at the same time as a tetrafluoroethylene target, and an adhesion layer made of a mixture of these materials was formed using polymethyl methacrylate.

When formed on four types of substrates: polycarbonate, epoxy, and glass, and subjected to beer-off tests, it was found that in adhesive layers with a uniform mixing ratio in the thickness direction, those with a tetrafluoroethylene mixing ratio of 50 vol.% or more No peeling occurred from any of the substrates, and no peeling was observed in the adhesive layer with a gradient-like mixture ratio change.

In addition, the present invention 1 can be implemented with various modifications without departing from the gist thereof.

[Brief explanation of drawings]

FIG. 1 shows an optical information recording medium (
FIG. 2 is a block diagram of a sputtering device as an example of the device used for manufacturing the optical disk of the present invention, and FIGS. ] - A microscopic photograph showing the surface metallographic structure after an accelerated deterioration test of an optical disk having a dense W layer consisting of a simple substance of lafluoroethylene, FIG. 4 is another example of the apparatus used for manufacturing the optical disk of the present invention. FIG. 5 is a block diagram of a plasma polymerization apparatus according to another embodiment of the present invention, and FIG. Figures 6(a) and 6(b), which are diagrams showing examples of ratio changes, show the surface metallographic structure of an optical disk having an adhesion layer in which the tetrafluoroethylene mixing ratio was changed stepwise and gradiently in the thickness direction. Microscope fMM photograph, Figure 7-
26 = (a) and (b) are micrographs showing the surface metal structure of an optical disc having an adhesive layer made of a mixture of tetrafluoroethylene and an inorganic material with a uniform mixing ratio of tetrafluoroethylene in the thickness direction. It is. DESCRIPTION OF SYMBOLS 1... Transparent resin substrate, 2... Adhesive layer, 3... Recording layer, 4... Interference layer, 5... Light reflective layer. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Qll Wholesale meeting

Claims (3)

[Claims] (1) An optical information recording medium having a translucent resin substrate and a recording layer that causes an optical change upon irradiation with a light beam, including a fluorocarbon resin between the translucent resin substrate and the recording layer. An optical information recording medium characterized by interposing a light-transmitting adhesive layer. (2) The optical information recording medium according to claim 1, wherein the adhesive layer further contains a translucent inorganic material. (3) In the adhesion layer, the mixing ratio x of the fluorocarbon resin is the average value of x in the thickness direction @x@, and on the side closer to the transparent substrate, x>@x@, and the recording layer 3. The optical information recording medium according to claim 2, wherein the thickness changes in the thickness direction so that x<@x@ on the side closer to .