JPS62130889A - Optical recording medium - Google Patents

Abstract

PURPOSE:To obtain an optical recording medium capable of optical writing with semiconductor laser, by a method wherein; one or more A layer(s) consisting of monomolecular film of diacetylene derivative compound having hydrophilic portions as well as hydrophobic portions and one or more B layer(s) consisting of a monomolecular film containing at least one among a pyrylium dye, a thiopyrylium dye, and a selenapyrylium dye, are so laminated as to have two or more joint surfaces of the A and B layers. CONSTITUTION:As a DA compound of diacetylene derivative compound having hydrophilic portions and hydrophobic portions, a compound shown by a formula (I) is typically used. On the other hand, a pyrylium dye group 5, i.e. a pyrylium dye, a thiopyrylium dye, and a selenapyrylium dye, is a compound shown by a structural formula (II) and has an absorption peak at 780-900nm and heats by irradiation of an infrared ray of this wave length. An optical recording medium consists of a substrate 1 and a recording layer 2 formed thereon. The three-layer recording layer 2 is so constructed as to form on a substrate 1 successively a B layer 4 containing the pyrylium dye group 5, an A layer 3 made of a monomolecular cumulative film of two degree made of the DA compound, and a B layer 4 of monomolecular film containing the pyrylium dye group 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording medium, and particularly to an optical recording medium suitable for optical writing using an infrared laser.

[Conventional technology]

Recently, optical discs have been attracting attention as a central player in office automation. Optical discs can store large amounts of documents, literature, etc. on a single disc, so
Organize and manage documents, etc. in the office efficiently. Various types of recording elements have been studied for this optical disk, but those using organic materials are attracting attention because of their cost and ease of manufacture.

Diacetylene derivative compounds are known as organic materials for such recording elements. Focusing on the thermochromic properties of these compounds, a recording technology for use in laser recording elements was disclosed in Japanese Patent Laid-Open No. 147807/1983. There is. However, this specification does not mention what kind of laser was used or should be used, and merely states that recording was performed using a laser.

The inventors investigated the laser recording of this diacetylene derivative compound using various lasers, and found that although thermochromic recording is possible using a large, high-power laser such as an argon laser, a small and relatively It was confirmed that laser recording could not be performed when a low-output semiconductor laser (wavelength: 800 to 850 nm) was used. However, for practical recording media such as optical discs, it is required that optical writing be possible using a small, low-output semiconductor laser.

On the other hand, JP-A-59-41383 and JP-A-59-
No. 148081 discloses various biryllium dyes, thiopyrylium dyes, and selenapyrylium dyes, and an organic film containing these dyes absorbs radiation in the semiconductor laser radiation wavelength range and generates heat, so that pits are formed by laser energy. It is disclosed that so-called heat mode recording can be carried out. However, when recording is performed by forming physical bits on the surface of a recording medium, the surface of the initial recording layer must be sufficiently smooth and at the same time the surface of the recording medium will not be scratched even after recording. In addition, it is relatively difficult to perform high-density, high-speed recording.

Further, the recording layer of these recording media is formed by dispersing microcrystals of diacetylene derivative compounds, beryllium dye, etc. in a binder.

The orientation of these compounds in the recording layer is random, which causes phenomena such as light absorption and reflectance to vary depending on location, and the degree of chemical reaction to vary, making it not necessarily suitable for high-density recording. I couldn't say that there were any.

[Problem that the invention seeks to solve]

The present invention has been made to solve the problems of the prior art, and an object of the present invention is to provide an optical recording medium that can be optically written with a small and lightweight semiconductor laser.

Another object of the present invention is to provide an optical recording medium capable of high-density, high-sensitivity, and high-speed recording.

Still another object of the present invention is to provide an optical recording medium with excellent stability and high quality.

[Means for solving problems]

That is, the optical recording medium of the present invention comprises one or more layers of layer A consisting of a monomolecular film or a cumulative film of a diacetylene derivative compound having at least a hydrophilic site and a hydrophobic site, and a biryllium dye, a thiopyrylium dye, and a selenapyryl dye. A monomolecular film containing one or more selected from the group consisting of lium dyes or one or more layers of B layer consisting of a cumulative film thereof are laminated, and has two or more bonding surfaces between Afi and B layer. It is characterized by having a recording layer formed by:

The diacetylene derivative compound (hereinafter abbreviated as DA compound) that has both a lignophilic site and a hydrophobic site used in the present invention is defined as a diacetylene derivative compound having both a lignophilic site and a hydrophobic site (hereinafter abbreviated as a DA compound). - There are 11 compounds capable of addition polymerization reaction 1
Typically, the following general formula % formula %) (wherein, X is a hydrophilic group forming a hydrophilic site,
(m and n represent integers) Examples include compounds represented by the following formula.

Examples of the wood-philic group X in the DA compound described above include a carboxyl group, an amino group, a hydroxy group, a nitrile group,
Examples thereof include a 1,000-alcohol group, an imino group, a sulfonic acid group, a sulfinyl group, or a metal or amine salt thereof.

The alkyl group represented by H(C:R2) forming the hydrophobic site is preferably a long-chain alkyl group having 1 to 30 carbon atoms. Further, n+m is preferably an integer of 1 to 30.

On the other hand, the biryllium dyes, thiopyrylium dyes, and selenapyrylium dyes (hereinafter abbreviated as biryllium dyes) used in the present invention have the following basic structure (wherein, X represents an oxygen atom, a sulfur atom, or a selenium atom, R1, R2, and R3 represent various organic residues, and A represents an anion.) A compound that has an absorption peak at 780 to 900 nm and generates heat by infrared light at this wavelength. It is. These biryllium dyes are typically represented by the following general formulas (1) to (3):
The dyes shown are exemplified.

General formula (1) General formula (2) Aθ General formula (3) (wherein R4, R5, R6, and R7 are substituted or unsubstituted 7-aryl groups such as phenyl, tolyl, xylyl, chlorophenyl, methoxyphnyl, or 2- Pyridyl,
3-pyridyl, 2-furyl, 2-chenyl, 2-thiazolyl, 3-carbazolyl, 2-quinolyl, 3-quinolyl, 2-imidazolyl, 2-levidyl, 3-methoxy-2
-pyridyl, 6-methyl-2-pyridyl, 4,5-dimethyl-2-thiazolyl, 4,5-diphenyl-2-thiazolyl, 4-phenyl-2-thiazolyl, 9-ethyl-
represents a substituted or unsubstituted heterocyclic group such as 3-carbazolyl, and at least one of R4, R", R", and R7 represents a substituted or unsubstituted heterocyclic group
R8 represents a hydrogen atom, an alkyl group such as methyl, ethyl, propyl, butyl, or a substituted or unsubstituted 7-aryl group such as phenyl, tolyl, xylyl, chlorophenyl, methoxyphnyl. R9 represents a methyl or ethyl group.

xl and X2 represent oxygen atom, sulfur atom or selenium atom, A is chloride ion, bromide ion, iodide ion, perchlorate ion, benzenesulfonate ion, P-toluenesulfonate ion, methyl sulfate Represents anions such as salt ions, ethyl sulfate ions, propyl sulfate ions, etc. ) Typical specific examples of these biryllium dyes are illustrated below. However, for convenience, all anions are represented by perchlorate ions.

A typical configuration of the optical recording medium of the present invention is shown in FIGS. 1 and 2.
An example is shown in the figure. In the example of FIG. 1, 8 layers 4, which are monomolecular films containing the pyrylium dyes 5, are formed on the substrate IL, and layer A 3, which is a monomolecular cumulative film of the DA compound with a cumulative degree of 2, is formed thereon. are laminated, and eight layers 4 of a monomolecular film containing biryllium dyes 5 are further formed thereon, and the recording layer 2 is constituted by these three layers. That is, this optical recording medium has two bonding surfaces between the A layer and the B layer. In the figure, 6 represents an organic carrier molecule, and the rectangular portions in this organic carrier molecule and OA compound represent hydrophobic portions, most of which represent woody portions. In the example shown in FIG. 2, the recording layer 2 is constructed by laminating the combination of the A layer 3 and the 8 layers 4 five times on the substrate 1.
has nine bonding surfaces between layer A and layer B. A layer 3 and 8
The stacking order with the layer 4 is not limited to the embodiments shown in these figures, and the layer present on the bonding surface with the substrate 1 or on the surface of the recording layer 2 may be either the A layer or the B layer. Also,
If necessary, other layers such as a transparent protective layer may be provided on the recording layer 2, for example.

The thickness of the recording layer 2 is not particularly limited, but it is practically preferable that the cumulative monomolecular layer including the A layer 3 and the 8 layers 4 is up to about 400.

As the substrate 1 of the optical recording medium of the present invention, various supporting materials such as glass, a plastic plate such as acrylic resin, a plastic film such as polyester, paper, and metal can be used. When performing recording, a material that transmits recording radiation of a specific wavelength is used.

In order to form the A layer 3 consisting of a monomolecular film or a monomolecular cumulative film of a DA compound on the substrate 1, for example, I.

The Langmuir-Prodgett method (hereinafter abbreviated as LB method) developed by Langmuir et al. is used. The LB method is
In molecules with a structure that has a parent wood group and a hydrophobic group in the molecule,
When the balance between the two (balance of amphiphilic properties) is maintained appropriately, this molecule forms a monomolecular layer on the water surface with the parent group facing down, forming a monolayer or monolayer. This is a method of creating layers that are cumulative. A monolayer on the water surface has the characteristics of a two-dimensional system. When the molecules are sparsely dispersed, the two-dimensional ideal gas equation, nA=kT, holds between the area per molecule A and the surface pressure ■, resulting in a "gas film." Here, is the Portzmann constant and T is the absolute temperature. If A is made sufficiently small, the intermolecular interaction becomes strong and a two-dimensional solid "condensed film (or solid l1l)" is formed. The condensed film can be transferred layer by layer to the surface of a substrate such as glass.

Using this method, a monomolecular film or a monomolecular cumulative film of an OA compound is produced, for example, as follows. First, DA
A compound is dissolved in a solvent such as chloroform, and this is spread on an aqueous phase to form a developed layer in which these compounds are developed into a film.Next, this developed layer freely diffuses and spreads on the aqueous phase. A partition plate (or a float) is provided to limit the area of the spread layer so that the DA compound aggregate state is controlled, and a surface pressure n proportional to the aggregate state is obtained. By moving this partition plate, the developed area is reduced to control the state of aggregation of the film material, and the surface pressure is gradually increased to create a surface pressure suitable for producing a cumulative film.
can be set. By vertically vertically moving a clean substrate or a substrate on which BFR is formed while maintaining this surface pressure, a monomolecular film of the OA compound is transferred onto the substrate or B layer. This is how the monolayer is made.

A monomolecular layer cumulative film having a desired degree of accumulation can be formed by repeating the above operations.

In addition to the above-mentioned vertical dipping method, methods such as a horizontal deposition method and a rotating cylinder method can be used to transfer the monomolecular film onto a substrate. The horizontal deposition method is a method in which the substrate is brought into horizontal contact with the water surface and transferred, and the rotating cylinder method is a method in which a cylindrical substrate is rotated on the water surface to transfer a monomolecular layer onto the surface of the substrate. In the vertical immersion method described above, when a substrate with a hydrophilic surface is lifted out of water in a direction transverse to the water surface, a monomolecular layer is formed on the substrate in which the parent group of the OA compound is oriented toward the substrate in the first layer. .

When the substrate is moved up and down, the monomolecular film is laminated one layer at each step.The direction of the film-forming molecules is reversed between the lifting step and the dipping step, so according to this method, the distance between the two layers is the same as the parent wood base. A Y-shaped film is formed in which the parent wood group, the hydrophobic group, and the hydrophobic group face each other.

On the other hand, the horizontal deposition method is a method in which the substrate is brought into horizontal contact with the water surface and transferred, and a monomolecular layer with the hydrophobic group of the OA compound facing the substrate is formed on the substrate. In this method, there is no change in the orientation of the DA compound molecules even if they are accumulated, and an X-type film is formed in which the hydrophobic groups face the substrate in all layers.On the contrary, in all layers the hydrophilic groups face the substrate. A side-facing cumulative film is called an X-type film.

The rotating cylinder method is a method in which a cylindrical substrate is rotated on the water surface to transfer a monomolecular layer onto the surface of the substrate.

The method of transferring the monomolecular layer onto the substrate is not limited to these methods, and when using a large-area substrate, a method of extruding the substrate from a substrate roll into an aqueous phase may also be used.

Furthermore, the orientation of the aforementioned parent wood group and hydrophobic group toward the substrate is a general rule, and can be changed by surface treatment of the substrate, etc.

Details of these monomolecular film transfer operations are already known and are described, for example, in "New Experimental Chemistry Course 18 Interfaces and Colloids", pages 498-507, published by Maruzen.

Note that the A layer 3 made of a monomolecular film or a monomolecular cumulative film of a DA compound is preferably a film made of an OA compound alone, but may be a film containing a small amount of an additive compound.

On the other hand, since biryllium dyes 5 are not amphiphilic substances, they cannot be used alone to form a monomolecular film by the LB method. The LB method can be applied by mixing appropriately balanced organic polymers as carrier molecules in any ratio. In other words, if the amphipathic balance of at least one compound is maintained, a monomolecular layer will be formed on the water surface, and the other compounds will be sandwiched between the amphipathic compounds, resulting in a well-ordered molecular layer as a whole. This is because a monomolecular layer is formed.

Therefore, it is difficult to form a single monomolecular film containing pyrylium dyes 5 or a cumulative film thereof, but the 8-layer 4, which is a monomolecular film containing pyrylium dyes 5 or a cumulative film thereof, is It can be easily formed by the LB method by using a chemical substance in combination.

By adopting this method, a film in which A layers 3 and 8 layers 4 are stacked alternately can be easily formed by the LB method, and such a cumulative film is an accumulation of different types of molecules)1 i
Therefore, it is hereinafter referred to as a hetero-cumulative film.

Although such a hetero-cumulative film was previously illustrated in FIGS. 1 and 2, it can be formed, for example, in the following manner.

■ Hetero-cumulative film in which the odd-numbered layer is a monomolecular film of [lA compound, and the even-numbered layer is a monomolecular film containing biryllium dyes, ■ Monomolecular cumulative film of OA compound with cumulative degree 2 and cumulative degree A hetero-cumulative film in which stacking of a monomolecular cumulative film containing pyrylium dyes and a monomolecular cumulative film containing pyrylium dyes as described in No. 6 is repeated several times; The hetero-cumulative film formed on the substrate in this way has a high density and a high degree of order. , the variation in light absorption depending on location is extremely small. Therefore, by configuring the recording layer with such a film, it is possible to obtain a recording medium that has a high-density, high-resolution recording function capable of optical recording and thermal recording according to the functions of the DA compound and biryllium dyes. It will be done.

Note that the layer A 3 formed as described above, consisting of a monomolecular film of the [lA compound or a cumulative film thereof, is irradiated with ultraviolet rays so that the OA compound formed as a monomolecular film or a cumulative film thereof is polymerized. It may be something that has been done.

The optical recording medium of the present invention allows various types of optical recording to be performed; however, by applying light or heat, the absorption wavelength of the recording layer changes and the apparent color changes. The recording mechanism using a semiconductor laser will be briefly explained below.

The OA compound is initially almost colorless and transparent, but when the recording layer is irradiated with ultraviolet rays, it polymerizes and changes into a polyacetylene derivative compound. This polymerization occurs only by irradiation with ultraviolet light and not by the application of other physical energy such as heat. As a result of this polymerization, the recording layer has an
It has a maximum absorption wavelength in nm, and the color changes from blue to dark. The change in hue due to this polymerization is an irreversible change, and once the recording layer changes to a dark blue color, it will not return to a colorless transparent film.Also, the polyacetylene derivative compound that has changed to a dark blue color will not be heated to about 50°C or above. When heated, the maximum absorption wavelength becomes approximately 540 nm, and the film changes to a red color. This change is also an irreversible change.

Therefore, optical recording using the optical recording medium of the present invention is performed by the following mechanism.

First, when the entire recording layer of the recording medium of the present invention is irradiated with ultraviolet rays, the DA compound in the recording layer polymerizes and changes into a polyacetylene derivative compound, thereby changing the recording layer 2 into a dark blue film. When a predetermined position on the recording medium is irradiated with a semiconductor laser beam 7 with a wavelength of 800 to 85 Qna+ that blinks in response to an information signal, the polyacetylene derivative compound does not absorb this laser beam 7, but
As shown in Fig. 3a, the pyrylium dyes 5 in the 8 layers 4 absorb this laser beam 7 and generate heat (the heat generating part is indicated by 8). The light is transmitted to the polyacetylene derivative compound of layer A 3 through the light, and the color changes to red. Thus, as shown in FIG. 3b, optical recording is performed by changing the color of the recording region 9 on the recording layer in accordance with the input information.

〔Effect of the invention〕

The effects of the optical recording medium of the present invention are listed below.

(1) Since the OA compound and the biryllium dye in the recording layer are each formed of a (mixed) monomolecular film or a cumulative film thereof, the recording layer has a high density and a high degree of order. Homogeneous recording is possible.

(2) Since the recording layer is formed as a Peter film having two or more bonding surfaces between the radiation absorbing layer and the thermosensitive color changing layer, the heat transfer efficiency is high and the sensitivity is extremely high.

(3) It is possible to produce a highly homogeneous recording layer at low cost even on a large-area support.

(4) Since the recording layer contains biryllium dyes that absorb infrared rays of 800 to 850 nm and generate heat,
The recording section uses a small and lightweight semiconductor laser that emits infrared rays of 850 nm.

(5) Since recording can be performed using changes in the hue of the recording layer due to light irradiation, high-speed, high-sensitivity, and high-density optical recording can be performed.

〔Example〕

Hereinafter, the present invention will be explained in more detail based on examples.

Example 1 (Preparation of LIA compound monomolecular film) General formula (+28+5-CmiC-(j C-C3H,6-
A diacetylene derivative compound represented by C0OH is added to chloroform in an amount of lXl0-3 mol/! A solution containing cadmium chloride at a pH of 6.5 and a concentration of 1X10-
It was developed on a 3 mol/l aqueous phase. After removing the solvent chloroform, while keeping the surface pressure constant, thoroughly clean the glass substrate with a hydrophilic surface (such as a cumulative film composed of a monomolecular film containing biryllium dyes). (including cases where the OA compound has been formed) is gently raised and lowered a predetermined number of times at a vertical speed of 1.0 cm/min in the direction across the water surface (a drying process is performed in the middle), and a monomolecular film of the OA compound is deposited on the substrate. The mixture was transferred to form a monomolecular film or a monomolecular cumulative film.

[Preparation of a monomolecular film containing biryllium dyes] A solution in which 1 part by weight of the thiopyrylium dye represented by the above-mentioned dye Sui 4 and 2 parts by weight of araxic acid were dissolved in chloroform at a concentration of lXl0-3 mol/l was dissolved at pH. was developed on an aqueous phase with a cadmium chloride concentration of 1X10-3 mol/l. After removing the solvent chloroform, while keeping the surface pressure constant, thoroughly clean the glass substrate with a hydrophilic surface (on which a cumulative film composed of a monomolecular film of an OA compound has already been formed). The monomolecular film containing biryllium dyes is transferred onto the substrate by gently raising and lowering it a predetermined number of times at a vertical speed of 1.0017 minutes in the direction across the water surface (with a drying process in between). Then, a monomolecular film or a monomolecular cumulative film was formed.

[Preparation of hetero-cumulative film]

Based on the above-mentioned process for producing an OA compound monolayer and a monolayer containing biryllium dyes, eight types of hetero-cumulative films were produced on a glass substrate by appropriately combining these operations. . Table 1 shows the hetero-cumulative film (optical recording medium) thus produced. The meanings of symbols and numbers indicating the structure of the optical recording medium are illustrated below.

■G /20PL/5ODA/20PL glass substrate (G
), a monomolecular cumulative a film containing biryllium dyes with a cumulative degree of 20 → a monomolecular cumulative film of a DA compound with a cumulative degree of 60 → a monomolecular cumulative film containing biryllium dyes with a cumulative degree of 20,
A recording medium configured by laminating layers in this order.

■G/IOX (2PL/8DA) glass substrate (
G) A stack consisting of a laminated combination of a monomolecular cumulative film containing biryllium dyes with a cumulative degree of 2 and a monomolecular cumulative film of an OA compound with a cumulative degree of 6, repeated 10 times. Medium.

Comparative Example 1 An optical recording medium was produced in which only a 41-layer monomolecular cumulative film of an OA compound was formed on a glass substrate.

Comparative Example 2 A film with a thickness of 1500 mm was formed on a glass substrate by sputtering.
A radiation absorbing layer made of Gd↑b*Fe of A was provided. An optical recording medium was produced in which a 41-layer monomolecular cumulative film was formed on the radiation absorption layer of this substrate.

Recording test l The optical recording medium prepared in Example 1 and Comparative Example 1.2 was
Uniform and sufficient irradiation with 54 nm ultraviolet rays.

R layer has a blue film, 0th order output 2mW, wavelength 830n
A semiconductor laser beam with a beam diameter of 1 μs is irradiated onto a predetermined position on the surface of each optical recording medium according to the input information (
During the irradiation time of 2 (lQns71 bits), a red recorded image was formed on the blue recording layer.

The evaluation of the recording results is shown in Table 1. The evaluation was made based on the quality of the image resolution and image density. Particularly good results were given O1, good results were O1, and those in which recording was not possible or poor were given "X". Furthermore, the recording sensitivity was evaluated based on the minimum irradiation time required to produce a readable color change record when the irradiation time of the laser beam was changed with the same output.

Comparative Example 3 A coating solution was prepared by dissolving 3 parts by weight of the thiopyrylium dye represented by the above-mentioned dye Sui 4 and 1 part by weight of nitrocellulose in 20 parts by weight of methylene chloride. This coating solution was applied to a glass disc substrate (
After dropping a small amount onto the center of a substrate (1.5 mm thick, 200 mm diameter), apply by rotating a spinner at a predetermined rotation speed for a predetermined time, dry at room temperature, and the thickness of the dried coating film on the substrate is IQOOA. An optical recording medium was created.

Recording Test 2 Regarding the optical recording medium of Comparative Example 3, a semiconductor laser beam was directly applied to a predetermined position on the surface of the optical recording medium with the same output as in Recording Test 1 according to the input information without performing ultraviolet irradiation, and the irradiation time was variously changed. irradiated onto the surface of the recording layer (irradiation time 5G)
Recording was carried out by forming pits. As a result of microscopic observation, it was found that in this recording medium, an irradiation time of 4 μs or more was required to clearly form one pit.

Example 2 General formula〇, 2H2s-(:=c-cmiC-C8Hl
6- Instead of the diacetylene derivative compound represented by C0OH, general formula C,)1. , - C=C-C=C-C,
An optical recording medium was prepared in the same manner as in Example 1 except that 2H4-GOOH was used.

Example 3 An optical recording medium was prepared in the same manner as in Example 1 except that a pyrylium dye represented by Dye A5 was used in place of the thiopyrylium dye represented by Dye Su-4.

Example 4 An optical recording medium was prepared in the same manner as in Example 5, except that the thiopyrylium dye represented by Dye 4 was replaced with a selenapyrylium dye represented by Dye 7.

Example 5 An optical recording medium was prepared in the same manner as in Example 8, except that a pyrylium dye represented by Dye Sut14 was used instead of the thiopyrylium dye represented by Dye Sut4.

Example 6 An optical recording medium was prepared in the same manner as in Example 8, except that the thiopyrylium dye represented by Dye No. 4 was replaced by the thiopyrylium dye represented by Dye No. 16.

Recording Test 3 A recording test was conducted in the same manner as Recording Test 1 using the optical recording media prepared in Examples 2 to 6. The evaluation of this recording result is shown in Table 2.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views illustrating the structure of the optical recording medium of the present invention. Figures 3a and 3b are
FIG. 1 is a schematic cross-sectional view showing a recording mode of the optical recording medium of the present invention. ■ = Substrate 2: Recording layer 3: A layer (layer containing diacetylene derivative compound) 4: 8 layers 5: Beryllium dyes 6: Organic carrier molecule
7: Laser beam 8: Heat generating area 9: Red discoloration area (recording area) Patent applicant Canon Co., Ltd. Agent Tadashi Wakabayashi 1 Figure 2

Claims (1)

[Scope of Claims] 1) One or more layers of layer A consisting of a monomolecular film or a cumulative film of a diacetylene derivative compound having at least a hydrophilic site and a hydrophobic site, and a pyrylium dye, a thiopyrylium dye, and a selenapyrylium dye. A monomolecular film containing one or more selected from the group consisting of one or more monomolecular films or a cumulative film thereof, and one or more B layers are laminated, and has two or more bonding surfaces between the A layer and the B layer. An optical recording medium characterized by having a recording layer consisting of: 2) The optical recording medium according to claim 1, wherein the recording layer is composed of a layer A and a layer B periodically stacked.