JP2866554B2 - Information recording medium, method of manufacturing the same, and method of using information recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium, a method of manufacturing the same, and a method of recording information on the information recording medium and reading and erasing the recorded information.

[0002]

2. Description of the Related Art Examples of conventional information recording media include thin-film inorganic magnetic materials for magnetic recording or magneto-optical recording,
There were organic photoisomerization substances for optical recording.

On the other hand, an LB (Langmuir-Blodgett) film is well known as an ultrathin film whose thickness can be controlled on the order of Angstrom or on the order of Angstrom. By using an organic substance having photoisomerization ability as a film constituent molecule of the LB film, a thin film recording medium having optical recording ability can be manufactured. For example, when a spiropyran derivative is used (E. Ando, J. Hibi)
no, T .; Hashida and K.S. Morimo
to, Thin Solid Films, 160, 2
79 (1988)) or when an azobenzene derivative is used (HS Blairand CB McArdl).
e, Polymer, 25, 1347 (1984)).

[0004]

However, in the conventional magnetic recording media using an inorganic magnetic material, the film thickness is limited to several hundreds of angstroms, which limits its use. On the other hand, in the conventional optical recording medium using the photoisomerized organic substance, the film thickness can be reduced by using the LB film, but there is a decisive problem in processing resistance, and therefore, it is far from practical use. Is the current situation.

According to the present invention, in order to solve the above-mentioned problems of the prior art, the film thickness can be controlled in the order of several to several tens of Angstroms, or in the order of several to tens of Angstroms. An object of the present invention is to provide an information recording medium and a method for manufacturing the same, and a method for recording, reading, and erasing information.

[0006]

In order to achieve the above object, a first information recording medium of the present invention is an information recording medium having an information recording layer provided on a base, wherein the information recording layer is a dicyclodextrin. It has a pentadiene skeleton and is characterized in that recording is performed by selectively opening the ring of the dicyclopentadiene skeleton.

[0007] A second information recording medium of the present invention is an information recording medium comprising an information recording layer provided on a base,
The information recording layer has a dicyclopentadiene skeleton, and the recording is performed by selectively taking in metal ions in a portion where the dicyclopentadiene skeleton is opened to form a metallocene skeleton. I do.

[0008] A third information recording medium of the present invention is an information recording medium comprising an information recording layer provided on a base,
The information recording layer has a cyclic skeleton, and the recording is performed by forming a metallocene skeleton or a metallocene-like skeleton by selectively incorporating a metal ion into a portion where the cyclic skeleton is opened. I do. In the above, the case where a metallocene-like skeleton is formed corresponds to, for example, a case where two benzene rings are incorporated in a sandwich form using chromium ions.

In the above structure, the cyclic skeleton is preferably at least one selected from a cyclopentadiene skeleton, a heterocyclic ring and a benzene ring. Further, in the above configuration, the information recording layer may be directly or indirectly fixed to the base by a chemical bond via at least one atom selected from C, Si, Ge, Sn, Ti, Zr, and S. preferable.

Further, in the above structure, the information recording layer has:
It is preferably at least one film selected from a monomolecular film, a monomolecular accumulation film, and a polymer film. Next, in the method for producing an information recording medium of the present invention, the functional group represented by the formula (Chem. 1), the functional group represented by the formula (Chem. 2), and the halogenated compound represented by the formula (Chem. 3) A molecule having at least one functional group selected from a sulfonyl group, a sulfinyl halide group represented by the above formula (Formula 4), and a cyano group (-CN) and having a cyclic skeleton is converted into an active hydrogen or an alkali metal. A step of contacting and reacting with a substrate having or being provided, and immobilizing the molecule on the substrate by a chemical bond.

In the above structure, the cyclic skeleton is preferably at least one selected from a dicyclopentadiene skeleton, a cyclopentadiene skeleton, a heterocyclic ring and a benzene ring.

Further, in the above configuration, the information recording layer has:
It is preferably at least one film selected from a monomolecular film, a monomolecular accumulation film, and a polymer film. Next, the first method of using the information recording medium of the present invention is to record information by a step of selectively opening the dicyclopentadiene skeleton by heat or light in an information recording layer containing the dicyclopentadiene skeleton. It is characterized by doing.

Next, the second method of using the information recording medium of the present invention is to selectively open the dicyclopentadiene skeleton by heat or light in the information recording layer containing the dicyclopentadiene skeleton, Information is recorded by a step of extracting a pentadiene proton to form a cyclopentadienide ion and a step of forming a metallocene skeleton by incorporating a metal ion between the cyclopentadienide ions.

Next, a third method of using the information recording medium of the present invention is characterized in that information is recorded by a step of forming a metallocene skeleton or a metallocene-like skeleton by incorporating metal ions between cyclic skeletons. I do.

In the above structure, the cyclic skeleton is preferably at least one selected from a cyclopentadiene skeleton, a heterocyclic ring and a benzene ring. In the above-described configuration, it is preferable to perform multiplex recording and / or multi-value recording by repeating the recording plural times while changing the recording location and the type of metal.

In the above structure, the selective ring opening of the dicyclopentadiene skeleton is preferably performed by using a scanning probe electron microscope. In the above structure, it is preferable that the information be read by detecting a difference in light absorption or a difference in refractive index between the cyclopentadiene skeleton and the dicyclopentadiene skeleton.

Further, in the above structure, information is read out by detecting a difference in light absorption or a difference in refractive index between a cyclopentadiene skeleton, a dicyclopentadiene skeleton, a heterocyclic ring or a benzene ring, and a metallocene or metal atom. Is preferred.

In the above structure, it is preferable that the recognition of the metallocene skeleton or the recognition of the metal atom is performed by using a scanning probe electron microscope or an electron beam.
Next, the method for using the information recording medium of the present invention has a configuration in which information on the information recording medium recorded by selective open polymerization of the dicyclopentadiene skeleton is erased by cycloaddition of the cyclopentadiene skeleton. Things.

Next, the method of using the information recording medium of the present invention is as follows.
It is provided with a configuration in which the information on the information recording medium recorded by the selective formation of the metallocene skeleton or the metallocene-like skeleton is erased by cleavage of the metallocene skeleton or the metallocene-like skeleton.

Next, the method of using the information recording medium of the present invention is as follows.
The information recording medium recorded by selective formation of the metallocene skeleton or the metallocene-like skeleton is erased by removing a portion containing the metallocene skeleton or the metallocene-like skeleton.

[0021]

The information recording medium of the present invention is firmly fixed directly or indirectly to the substrate by covalent bonding, and is a strong ultra-thin film information recording medium which has not existed before. In principle, film formation and film thickness control on the order of angstroms are possible.

The information recording medium of the present invention, the method of manufacturing the same, and the method of recording information on the information recording medium and reading the recorded information are performed by a chemical adsorption method on a substrate using a cyclopentadiene skeleton, a heterocyclic ring, a benzene ring or An information recording layer made of constituent molecules having at least one selected from a dicyclopentadiene skeleton is provided. When the information recording layer has a dicyclopentadiene skeleton, recording is performed by selective ring opening of the dicyclopentadiene skeleton. The reading of recorded information utilizes the difference in light absorption sensitivity or the difference in refractive index between the cyclopentadiene skeleton and the dicyclopentadiene skeleton. Also,
In the case of having dicyclopentadiene, a metal ion can be selectively formed between the cyclopentadiene rings formed by selective ring opening of the dicyclopentadiene skeleton, and between the cyclopentadiene or heterocyclic ring or the benzene ring in the case of having a benzene ring. Recording is performed by forming a metallocene skeleton or a metallocene-like skeleton by incorporation, and reading of the recorded information utilizes a difference in light absorption sensitivity or refractive index difference of a metallocene portion or a metal atom.

The information can be erased by cycloaddition of the cyclopentadiene skeleton (first method), cleavage of the metallocene skeleton (second method), and removal of the metallocene portion (third method). Method). In the second method, reductive cleavage with a base is appropriate. In this method, only the metal is removed, the cyclopentadiene skeleton remains, and recording can be performed again. In the third method, the portion containing the metallocene is removed, so that it is not possible to record again.

In the dicyclopentadiene skeleton, two adjacent cyclopentadienes are formed by a Diels-Alde
It is formed by cycloaddition by the r reaction and is stable at room temperature. As a method for forming an information recording layer having a dicyclopentadiene skeleton, there is a method in which a dicyclopentadiene derivative is used as a material or a method in which a dicyclopentadiene skeleton is introduced through the above cycloaddition using a cyclopentadiene derivative. , May be used.

As a means for opening the ring of the dicyclopentadiene skeleton, heat or light is suitable. As the heat source or the light source, a light source having a small aperture diameter and a large energy is preferable. For example, a semiconductor laser is preferably used. Note that the semiconductor laser can also be used for reading information.

In addition, when a ring of the dicyclopentadiene skeleton is opened and information is read out, if a scanning probe microscope or the like is used, it is possible to record and read out at the molecular and atomic level.

The metal ions used to form the metallocene skeleton or metallocene-like skeleton include Cr,
Examples include Mn, Fe, Co, Ni, Os, Ru, and V ions, but are not limited thereto. In the above, Fe, Ru, and Os are preferable in view of the stability of the formed metallocene.

Further, the second and third information recording media of the present invention can be in principle multiplex-recorded and / or multi-valued recording media by repeating the same recording process while changing metal ions. However, when a dicyclopentadiene skeleton is used for the recording layer, heat or light having an energy enough to open the ring of the dicyclopentadiene and not to decompose the already formed metallocene skeleton or metallocene-like skeleton may be given. is necessary. On the other hand, at the time of reading, the metallocene skeleton or metallocene-like skeleton, or the type of metal may be identified, or a different metallocene or metallocene-like skeleton, or a different metal may be identified. For that purpose, it is appropriate to use the difference in absorption sensitivity or the difference in refractive index of each light.

As the information recording layer on the substrate, an organic polymer film or an organic thin film having a cyclopentadiene skeleton, a heterocyclic ring, a benzene ring or a dicyclopentadiene skeleton is suitable, but is not limited to these. is there. Further, having a cyclopentadiene skeleton includes, of course, a case having an indenine derivative group or a fluorene derivative group, and also includes a heterocycle or a benzene ring as a part of a certain group in a heterocycle or a benzene ring. Including the case. However,
In terms of the density of the cyclopentadiene skeleton, the heterocyclic ring, the benzene ring, or the dicyclopentadiene skeleton, and the thickness of the film, a monomolecular film or a monolayer film of several layers is preferable. Further, considering durability including processing resistance after film formation, a chemisorption monomolecular film or a chemisorption monomolecular accumulation film is appropriate. In the case of using a chemisorption monomolecular accumulation film, a different metallocene skeleton or metallocene-like skeleton may be formed for each layer, or a different metallocene skeleton or metallocene-like skeleton may be formed in each layer, and such a mixed layer may be formed. May be laminated.
This makes it possible to perform high-density recording of a plurality of bits on one spot anyway.

Further, since the first information recording medium of the present invention can be recorded and erased without any physical addition or removal, recording and erasing can be performed any number of times. In this case, recording is performed by opening the ring of dicyclopentadiene, and erasing of the recording is performed by cycloaddition of dicyclopentadiene.

[0031]

The present invention will be described more specifically with reference to the following examples. The basic technique of the chemisorption method is described, for example, in Journal of Chemical Society, Vol. 102, p. 92 (J. Sagiv et al., J. Am. Che.
m. Soc. , 92, 102 (1980)) and Langmuir, Vol. 6, page 851 (K. Ogawa et a.
l. , Langmuir, 6, 851 (1990)). This chemisorption method is a method of immobilizing a molecule called a chemical adsorbent having a chlorosilyl group on a substrate having a hydroxyl group or the like on the surface thereof through a dehydrochlorination reaction.

In forming the chemically adsorbed film, the functional groups for fixing the molecules to the substrate include a functional group represented by the above formula (1), a functional group represented by the above formula (2), and a functional group represented by the above formula (2). At least one functional group selected from the group consisting of a halogenated sulfonyl group represented by the formula (3), a halogenated sulfinyl group represented by the formula (Formula 4), and a cyano group (—CN) is included, but the present invention is not limited thereto. Of course it is not. However, the halogen here is Cl, B
Although r or I can be mentioned, the same chemisorption monomolecular film and chemisorption monomolecular accumulation film can be obtained with Br or I, but Cl is preferable in terms of reactivity.

The substrate on which the chemical adsorption film is immobilized includes a hydroxyl group, a carboxyl group, a sulfonic acid group, a sulfinic acid group, a phosphoric acid group, a phosphorous acid group,
A quaternary ammonium group, a quaternary phosphonium group, a thiol group, at least one functional group selected from an amino group and / or a hydroxyl group, a carboxyl group, a sulfonic acid group, a sulfinic acid group, a phosphoric acid group, a phosphorous acid group, Quaternary ammonium group, quaternary phosphonium group, thiol group,
One having at least one functional group selected from a functional group in which H of at least one functional group selected from amino groups is substituted with an alkali metal or an alkaline earth metal,
And already fixed on a substrate having the functional group described above,
In addition, a chemical adsorption film having the above-described functional group on the film may be mentioned, but it is a matter of course that the present invention is not limited thereto.

When the above-mentioned functional groups are not present on the substrate surface or are small, it is effective to produce or increase the number of the functional groups by applying UV irradiation, oxidizing agent treatment or the like to modify the surface. It is.

As a method for fixing the chemical adsorption film on the substrate, there is a method in which the substrate is brought into contact with a liquid and / or gaseous chemical adsorbent and / or a solution in which the chemical adsorbent is dissolved. However, it is needless to say that the present invention is not limited to these.

When used as a solution here, it is appropriate that the solvent to be used is composed of molecules containing no active hydrogen. For example, when the chemical adsorbent has a long-chain alkyl group, a mixed solvent of hydrocarbons and halogenated carbons is used.When the chemical adsorbent has a carbonyl group, halogenated hydrocarbons and aromatics are used. It is appropriate to use
Of course, it is not limited to these.

After fixing the chemisorption film on the substrate,
It is preferable to add a step of removing unreacted molecules because a monomolecular film and a monomolecular cumulative film can be easily formed. An aprotic solvent is preferable as a solvent used in the washing and removal. For example, halogenated carbons, ethers, lactones, esters, nitriles, amides and the like can be mentioned, but it goes without saying that they are not limited to these.

Hereinafter, the present invention will be described in detail.
However, the present invention is not limited to the following examples. (Example 1) First, an adsorption solution A was prepared.

A mixture of hexadecane, carbon tetrachloride and chloroform at a weight ratio of 80: 12: 8 was mixed with about 1% by weight of (3-dicyclopentadienylpropyl) trichlorosilane as a chemical adsorbent. It was prepared by dissolving at a concentration, and this was designated as adsorption solution A. As shown in FIG. 1, a glass substrate was used as the substrate 1, washed with an organic solvent, dried, and then immersed in the adsorption solution A for 3 hours. The substrate 1 has a hydroxyl group (-OH). With this process,
First, a bond represented by the following formula (Formula 5) was formed, and a chemical adsorption film precursor was formed on the glass substrate 1.

[0040]

Embedded image

Next, washing with chloroform in the non-aqueous solvent for 15 minutes and washing with water for 15 minutes were performed, as shown in FIG.
A chemisorption monomolecular film 2 was formed. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

This was measured by Fourier transform infrared absorption spectrum (FTIR) measurement of 2925 and 2855 (attribution:-
CH ₂ —), 1650 (assignment: C ＝ C), 1465 (assignment: —CH ₂ —), 1080 (assignment: Si—O) cm ⁻¹
The formation of a film was confirmed by obtaining a signal characteristic of this structure.

The glass substrate having the chemically adsorbed monomolecular film 1 is immersed in decalin, and only a part of the glass substrate is heated to about 190 ° C. for 1 hour with an infrared laser.
aH was added followed by anhydrous FeCl ₂ .

After rinsing with hexane for 10 minutes and rinsing with water for 10 minutes after the above treatment, a chemically adsorbed monomolecular film 3 was formed in which only the infrared laser irradiated portion shown in FIG. 3 changed to a ferrocene skeleton. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

It should be noted that this is 1650 cm by FTIR measurement.
The signal of ^-1 disappeared, a signal characteristic of this structure was newly obtained at 815 (assignment: ferrocene skeleton) cm ^-1, and the presence of Fe atom could be confirmed by X-ray photoelectron spectroscopy (XPS) measurement. That was confirmed. This indicates that a signal can be recorded as ferrocene on the laser irradiation part.

Example 2 A glass substrate having a chemically adsorbed monomolecular film 2 prepared in Example 1 was immersed in decalin.
After heating only a part of the dicyclopentadiene skeleton without a ferrocene skeleton, that is, an unconverted dicyclopentadiene skeleton by an infrared laser for 1 hour, NaH was added into decalin, and then anhydrous RuCl ₂ was added.

After the above treatment, washing with hexane for 10 minutes and washing with water for 10 minutes resulted in the formation of a chemically adsorbed monomolecular film 4 in which a ferrocene skeleton and a ruthenocene skeleton shown in FIG. 4 were mixed. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

This is 821 cm ^-1 measured by FTIR.
New signal appears, and X-ray photoelectron spectroscopy (XP
S) The measurement was confirmed by the fact that the presence of Ru atoms in addition to Fe atoms could be newly confirmed. This indicates that information recorded with light at 821 cm ^-1 and 815 cm ^-1 can be identified and read.

Example 3 The surface of the chemically adsorbed monomolecular film 4 prepared in Example 2 was observed in ethanol with an atomic force microscope (AFM), which is a kind of scanning probe microscope. In Examples 1 and 2, the portion irradiated with the infrared laser was observed. Then, irregularities could be clearly observed on the surface of the film at each location, and it should be noted that there were three types of irregularities. This was interpreted as follows.

That is, the metallocene formed as a result of the reaction is 2
It is considered that three types of irregularities were observed because there are some types and, in addition, there are places where the unreacted dicyclopentadiene skeleton remains.

Example 4 First, an adsorption solution B was prepared. It is prepared by dissolving 14-iodotetradecyltrichlorosilane as a chemical adsorbent at a concentration of about 1% by weight in a mixed solvent of hexadecane, carbon tetrachloride and chloroform in a weight ratio of 80: 12: 8. Was designated as adsorption solution B.

A glass substrate was used as a substrate, washed with an organic solvent and dried, and then immersed in the adsorption solution B for 3 hours.
By this treatment, first, a bond represented by the following formula (Formula 6) was formed, and a chemically adsorbed film precursor was formed on the glass substrate.

[0053]

Embedded image

Next, washing with a non-aqueous solvent for 15 minutes with chloroform and washing with water for 15 minutes were carried out, as shown in FIG.
A chemically adsorbed monomolecular film 5 was formed. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

It should be noted that this is 2925, 2 by FTIR measurement.
855 (Ownership: -CH ₂ -), 1465 (attribution: -CH
₂ −), a signal characteristic of this structure was obtained at 1080 (assignment: Si—O) cm ⁻¹ , thereby confirming film formation.

The glass substrate having the chemically adsorbed monomolecular film 4 was immersed in dry THF under nitrogen, and sodium cyclopentadienide was added thereto and reacted for 30 minutes. By this reaction, a cyclopentadiene skeleton can be introduced on the film,
This means that immediately at room temperature, two adjacent cyclopentadiene skeletons are cycloadded to form a dicyclopentadiene skeleton,
A chemically adsorbed monomolecular film 6 as shown in FIG. 6 was formed.

It should be noted that this was newly determined by FTIR measurement to be 165.
Film formation was confirmed by obtaining a signal characteristic of this structure at 0 (assignment: C = C) cm ^-1 . This means that
This indicates that information recorded with light of 50 cm ^-1 can be read.

The glass substrate having the chemically adsorbed monomolecular film 5 was immersed in decalin, and only a part of the infrared laser was heated to about 190 ° C. for 1 hour.
H was added, followed by anhydrous FeCl ₂ .

After the above treatment, washing with hexane for 10 minutes and washing with water for 10 minutes resulted in formation of a chemically adsorbed monomolecular film 7 in which only the infrared laser irradiated portion shown in FIG. 7 changed to a ferrocene skeleton. . This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

It should be noted that a signal characteristic of this structure was obtained at 815 (assignment: ferrocene skeleton) cm ^-1 by FTIR measurement, and the presence of Fe atom could be confirmed by X-ray photoelectron spectroscopy (XPS) measurement. That was confirmed. This indicates that information recorded with light of 815 cm ^-1 can be read.

Example 5 First, an adsorption solution C was prepared. A mixture of hexadecane, carbon tetrachloride and chloroform at a weight ratio of 80: 12: 8 was mixed with about 1-dichloropentadienyl-1,8-di (trichlorosilyl) octane as a chemical adsorbent in about 1: 1. It was prepared by dissolving at a concentration of weight%, and this was designated as adsorption solution C.

A glass substrate was used as a substrate, washed with an organic solvent and dried, and then immersed in the adsorption solution C for 3 hours.
By this treatment, first, a bond represented by the following formula (Formula 7) was formed, and a chemically adsorbed film precursor was formed on the glass substrate.

[0063]

Embedded image

Next, washing with chloroform of the non-aqueous solvent for 15 minutes and washing with water for 15 minutes were performed, as shown in FIG.
A chemically adsorbed monomolecular film 8 was formed. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

It should be noted that this is 2925, 2
855 (Ownership: -CH ₂ -), 1650 (attribution: C =
C), a signal characteristic of this structure was obtained at 1465 (assignment: -CH _2- ), 1080 (assignment: Si-O) cm ^-1 , thereby confirming film formation.

The glass substrate having the chemically adsorbed monomolecular film 7 thus prepared is immersed in decalin and heated at about 190 ° C.
After heating for an hour, NaH was added into decalin and then F
eCl ₂ was added.

After the above treatment, washing with hexane for 10 minutes and washing with water for 10 minutes resulted in formation of the chemically adsorbed monomolecular film 9 having a ferrocene skeleton shown in FIG. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

Note that this was measured by FTIR and found to be 1650c
The signal of m ^-1 disappeared, a signal characteristic of this structure was newly obtained at 815 (assignment: ferrocene skeleton) cm ^-1, and the presence of Fe atom was determined by X-ray photoelectron spectroscopy (XPS) measurement. The confirmation confirmed the formation of the ferrocene skeleton.

Next, the glass substrate having the chemically adsorbed monomolecular film 8 is immersed in the adsorbing solution C for 3 hours in the same manner, and then washed to form the chemically adsorbed monomolecular accumulated film 10 as shown in FIG. It was formed on a glass substrate. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

It should be noted that this is 2925, 2 by FTIR measurement.
855 (Ownership: -CH ₂ -), 1465 (attribution: -CH
₂ −), the signal formation at 1080 (attribution: Si—O) cm ⁻¹ was approximately doubled, thereby confirming the film formation.

The thus prepared chemically adsorbed monomolecular cumulative film 1
A glass substrate having a thickness of about 190
After heating to 1 ° C. for 1 hour, NaH was added into decalin, followed by RuCl ₂ .

After the above treatment, washing with hexane for 10 minutes and washing with water for 10 minutes resulted in formation of a chemically adsorbed monomolecular film 11 having a ruthenocene skeleton shown in FIG. This monomolecular cumulative film was firmly fixed to the substrate and was rich in water repellency.

This was measured by FTIR and found to be 1650 c
The signal of m ^-1 disappeared, the signal of 821 (attribution: ruthenocene skeleton) cm ^-1 newly appeared, and the presence of Ru atom was confirmed by X-ray photoelectron spectroscopy (XPS) measurement, whereby the formation of the ruthenocene skeleton was confirmed. Was confirmed. This means that
Identifies the information recorded with light of 21cm ^-1 and 815 cm ^-1 indicates that the read out.

Example 6 A glass substrate 1 having a chemically adsorbed monomolecular film 7 prepared in Example 4 was immersed in ice-cooled methylene chloride, and ethylamine was added thereto. Three minutes later, lithium powder was added and left for 10 minutes. After quenching with methanol, washing with chloroform for 10 minutes and washing with water for 10 minutes resulted in the formation of a chemically adsorbed monomolecular film 12 as shown in FIG. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

Note that this was measured by FTIR and found to be 815 cm.
^-1 signal has disappeared, and X-ray photoelectron spectroscopy (X
Since the presence of Fe atoms could not be confirmed by PS) measurement, disappearance of the ferrocene skeleton was confirmed. That is, 81
It can be confirmed that the recorded information can be read out by using the light of 5 cm ⁻¹ , and that the information recorded by this method can be erased.

Example 7 First, an adsorption solution D was prepared. Dissolve (3-cyclopentadienylpropyl) trichlorosilane as a chemical adsorbent at a concentration of about 1% by weight in a mixed solvent in which hexadecane, carbon tetrachloride, and chloroform are mixed at a weight ratio of 80: 12: 8. It was prepared and used as an adsorption solution D.

A glass substrate was used as a substrate, washed with an organic solvent and dried, and then immersed in the adsorption solution D for 3 hours.
By this treatment, first, a bond represented by the following formula (Formula 8) was formed, and a chemically adsorbed film precursor was formed on the glass substrate.

[0078]

Embedded image

Next, washing with a non-aqueous solvent for 15 minutes with chloroform and washing with water for 15 minutes resulted in the formation of a chemically adsorbed monomolecular film 13 as shown in FIG. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

This is the result of FTIR measurement of 2925, 2
855 (Ownership: -CH ₂ -), 1650 (attribution: C =
C), 1465 (attribution: —CH ₂ —), 1080 (attribution: Si—O) cm ⁻¹ , and a signal characteristic of this structure was obtained, thereby confirming the film formation.

The glass substrate having the chemically adsorbed monomolecular film 12 was immersed in decalin, NaH was added therein, and then anhydrous FeCl ₂ was added. After the above treatment, washing with hexane for 10 minutes and washing with water for 10 minutes resulted in the formation of the chemically adsorbed monomolecular film 14 changed to the ferrocene skeleton shown in FIG. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

This is 1650 cm by FTIR measurement.
The signal of ^-1 disappeared, a signal characteristic of this structure was newly obtained at 815 (assignment: ferrocene skeleton) cm ^-1, and the presence of Fe atom could be confirmed by X-ray photoelectron spectroscopy (XPS) measurement. That was confirmed. This means that 815
This indicates that information recorded with light of cm ^-1 can be read.

Example 8 First, an adsorption solution E was prepared. Dissolve (8-dicyclopentadienyloctyl) trichlorosilane as a chemical adsorbent at a concentration of about 1% by weight in a mixed solvent in which hexadecane, carbon tetrachloride, and chloroform are mixed at a weight ratio of 80: 12: 8. Prepared
This was designated as adsorption solution E. Next, the glass substrate 1 as a hydrophilic substrate as shown in FIG. 1 was used, washed with an organic solvent, and then immersed in the adsorption solution E for 3 hours. Then, chloroform washing of the non-aqueous solvent for 15 minutes and water washing for 15 minutes are performed,
Then, when heated at 100 ° C. for 20 minutes under a nitrogen stream, FIG.
5, a chemically adsorbed monomolecular film 15 was formed. This monomolecular film was firmly fixed to the substrate and was rich in water repellency.

This was determined by FTIR measurement in 2925, 2
855 (Ownership: -CH ₂ -), 1650 (attribution: C =
C), a signal characteristic of this structure was obtained at 1465 (assignment: -CH _2- ), 1080 (assignment: Si-O) cm ^-1 , thereby confirming film formation.

Just half of the glass substrate 1 having the chemically adsorbed monomolecular film 15 was heated at about 190 ° C. with an infrared laser.
And then again measured by FTIR. As a result, signals were observed which can be attributed to skeletal vibration of aromatic in 1660,1610Cm ^-1, the signal of 1650 cm ^-1 was reduced to 45%.

From this, it was confirmed that the dicyclopentadiene skeleton, which had been initially formed, was polymerized by laser irradiation to form a cyclopentadiene ring. That is, it was found that the chemically adsorbed monomolecular film 16 as shown in FIG. 16 was formed.

Further, after 5, 10, 30, and 60 days later, FTIR measurement was again performed to track the change, but no change was observed. Next, this was heated with an infrared laser at 70 ° C. for 2 minutes, and FTIR measurement was performed again.

[0088] As a result, the signal of 1660,1610cm ^-1 disappeared, it was confirmed that the intensity of the signal of 1650cm ^-1 had been recovered on the strength of the measurement at the time of creating the film. In addition, it was confirmed that the information recording layer could be similarly formed even when a functional group other than the functional group used in Examples 1 to 8 was used.

[0089]

As described above, according to the present invention, it is possible to provide an information recording medium which enables thinner, stronger and higher-density multiplex recording. In addition, considering the practical aspect, it is hard to imagine its value in the field of advanced technology. It is possible to provide an information recording medium which can replace the conventional information recording medium and is suitable for applications that can exhibit excellent characteristics.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a main part of a substrate according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of the chemisorption monomolecular film of Example 1 of the present invention.

FIG. 3 is an enlarged view of a main part of the chemisorption monomolecular film of Example 1 of the present invention.

FIG. 4 is an enlarged view of a main part of a chemisorption monomolecular film of Example 2 of the present invention.

FIG. 5 is an enlarged view of a main part of a chemisorption monomolecular film of Example 4 of the present invention.

FIG. 6 is an enlarged view of a main part of a chemisorption monomolecular film of Example 4 of the present invention.

FIG. 7 is an enlarged view of a main part of a chemisorption monomolecular film of Example 4 of the present invention.

FIG. 8 is an enlarged view of a main part of the chemisorption monomolecular film of Example 5 of the present invention.

FIG. 9 is an enlarged view of a main part of a chemisorption monomolecular film of Example 5 of the present invention.

FIG. 10 is an enlarged view of a main part of the chemisorption monomolecular film of Example 5 of the present invention.

FIG. 11 is an enlarged view of a main part of the chemisorption monomolecular film of Example 5 of the present invention.

FIG. 12 is an enlarged view of a main part of a chemisorption monomolecular film of Example 6 of the present invention.

FIG. 13 is an enlarged view of a main part of the chemisorption monomolecular film of Example 7 of the present invention.

FIG. 14 is an enlarged view of a main part of the chemisorption monomolecular film of Example 7 of the present invention.

FIG. 15 is an enlarged view of a main part of a chemisorption monomolecular film of Example 8 of the present invention.

FIG. 16 is an enlarged view of a main part of a chemically adsorbed monomolecular film of Example 8 of the present invention after laser irradiation.

[Explanation of symbols]

1 Glass substrate 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14,
15,16 Chemisorption monomolecular film 10,11 Chemisorption accumulation film

Continuation of front page (58) Fields investigated (Int.Cl. ⁶ , DB name) G11B 11/00 B41M 5/26 G11B 7/00 G11B 7/24 516 G11B 9/00

Claims (21)

(57) [Claims] 1. An information recording medium comprising an information recording layer provided on a substrate, wherein the information recording layer has a dicyclopentadiene skeleton, and the information is recorded by selectively opening the dicyclopentadiene skeleton. An information recording medium characterized by performing the following. 2. An information recording medium having an information recording layer provided on a substrate, wherein the information recording layer has a dicyclopentadiene skeleton, and a portion where the dicyclopentadiene skeleton is selectively opened. An information recording medium for recording by incorporating a metal ion into a metallocene skeleton. 3. An information recording medium comprising an information recording layer provided on a substrate, wherein the information recording layer has a cyclic skeleton, and metal ions are selectively taken in between the cyclic skeletons. Alternatively, an information recording medium characterized in that recording is performed by forming a metallocene-like skeleton. 4. The cyclic skeleton is a cyclopentadiene skeleton,
The information recording medium according to claim 3, which is at least one selected from a heterocycle or a benzene ring. 5. The information recording layer is directly or indirectly fixed to a substrate by a chemical bond via at least one atom selected from C, Si, Ge, Sn, Ti, Zr, and S. The information recording medium according to claim 1, 2, or 3. 6. The information recording medium according to claim 1, wherein the information recording layer is at least one film selected from a monomolecular film, a monomolecular accumulation film, and a polymer film. 7. A functional group represented by the general formula (Chemical Formula 1), a functional group represented by the general formula (Chemical Formula 2), and a general formula (Chemical Formula 3) at one end.
A sulfonyl halide group represented by the general formula (Formula 4)
A halogenated sulfinyl group, a cyano group (-C
A molecule having at least one functional group selected from N) and having a cyclic skeleton is brought into contact with and reacted with a substrate having or provided with active hydrogen or an alkali metal, and the molecule is chemically formed on the substrate. A method for manufacturing an information recording medium, comprising a step of forming an information recording layer by fixing by bonding. Embedded image Embedded image Embedded image Embedded image 8. The information recording medium according to claim 7, wherein the cyclic skeleton is at least one selected from a dicyclopentadiene skeleton, a cyclopentadiene skeleton, a heterocyclic ring, and a benzene ring. 9. The method according to claim 7, wherein the information recording layer is at least one selected from a monomolecular film, a monomolecular accumulation film, and a polymer film. 10. A method of using an information recording medium, wherein information is recorded by selectively opening the dicyclopentadiene skeleton by heat or light in an information recording layer containing a dicyclopentadiene skeleton. . 11. In an information recording layer containing a dicyclopentadiene skeleton, the dicyclopentadiene skeleton is selectively opened by heat or light, and then a cyclopentadiene proton is extracted to form a cyclopentadienide ion. A method of using an information recording medium, wherein information is recorded by a step and a step of forming a metallocene skeleton by incorporating a metal ion between the cyclopentadienide ions. 12. A metallocene by forming an organic thin film containing a cyclopentadiene skeleton, a heterocyclic ring or a benzene ring on a substrate, and incorporating a metal ion between at least two of the cyclopentadiene, the heterocyclic ring and the benzene ring. Use of an information recording medium for recording information by a step of forming a skeleton or a metallocene-like skeleton. 13. A method of using an information recording medium for performing multiplex recording and / or multi-level recording by repeating the method according to claim 11 or 12 a plurality of times while changing the recording location and the type of metal. 14. The method according to claim 1, wherein the selective ring-opening of the dicyclopentadiene skeleton is performed using a scanning probe electron microscope.
13. Use of the information recording medium according to 1 or 12. 15. A method of using an information recording medium for reading out information by detecting a difference in light absorption or a difference in refractive index between a cyclopentadiene skeleton and a dicyclopentadiene skeleton. 16. The method according to claim 15, wherein the recognition of the cyclopentadiene skeleton or the recognition of the dicyclopentadiene skeleton is performed using a scanning probe microscope or an electron beam. 17. Use of an information recording medium for reading information by detecting a difference in light absorption or a difference in refractive index between a cyclopentadiene skeleton, a dicyclopentadiene skeleton, a heterocyclic ring or a benzene ring, and a metallocene or metal atom. Method. 18. The method according to claim 17, wherein the recognition of the metallocene skeleton or the recognition of the metal atom is performed using a scanning probe microscope or an electron beam. 19. Erasing information on an information recording medium recorded by selective open polymerization of a dicyclopentadiene skeleton,
Use of an information recording medium by cycloaddition of a cyclopentadiene skeleton. 20. A method of using an information recording medium in which information on an information recording medium recorded by selectively forming a metallocene skeleton or a metallocene-like skeleton is erased by cleavage of the metallocene skeleton or the metallocene-like skeleton. 21. A method of using an information recording medium in which information on an information recording medium recorded by selectively forming a metallocene skeleton or a metallocene-like skeleton is deleted by removing a portion containing the metallocene skeleton or a metallocene-like skeleton.