JP2013159517A - Organic carbon film and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic carbon film with high hardness, which is producible by a wet film forming method.SOLUTION: An organic carbon film has hardness evaluated by a pencil hardness test of 2H or higher. In a method for producing the organic carbon film, a film formed by wet film forming using a solution of a fullerene derivative is heat-treated at 400 to 1,000°C. The organic carbon film with high hardness is obtainable by heat-treating a fullerene derivative film formed by wet film forming at a high temperature region where decomposition of fullerene starts.

Description

The present invention relates to an organic carbon film, and more particularly to a high-hardness organic carbon film obtained by heat-treating a fullerene derivative film formed by a wet film forming method.
The present invention also relates to a method for producing the organic carbon film and a laminate including the organic carbon film.

  In the present invention, the “organic carbon film” is not a film made of only carbon, but a carbon film containing an ignition loss component mainly composed of an organic substance, which shows a decrease in mass in an ignition loss test (ignition loss test). Sure.

  Carbon-based materials have been used for a long time as bulk materials such as diamond and graphite (graphite), but in recent years they are also attracting attention as coating materials and functional thin film materials. Among them, an amorphous carbon film typified by diamond-like carbon (DLC) has a hardness as high as about 6H evaluated by a pencil hardness method according to the present invention, which will be described later, and has a low friction coefficient, smoothness, wear resistance, Since it is excellent in insulation, chemical resistance, etc., it is used for aluminum processing molds, protective films for tools and the like, protective films for optical elements, coating on sliding surfaces of magnetic heads, and the like.

  For the formation of the amorphous carbon film, a vapor phase growth method such as a high frequency plasma method or a plasma chemical vapor deposition method is mainly used (for example, Patent Document 1). However, since these vapor phase growth methods all require a large vacuum device, the film forming cost is high and the film is not suitable for forming a large area film.

  In addition, fullerene is a carbon-based material that has attracted attention in recent years. Fullerene is a generic name for carbon molecules having a spherical closed shell structure, and has unique properties derived from the molecular structure such as ultraviolet absorption characteristics, photoconductivity, and photosensitization characteristics. A wide range of applications to electronic materials, functional optical materials, coating materials replacing conventional amorphous carbon thin films, and the like are expected, and studies on the formation of fullerene thin films on substrates have been actively conducted in recent years.

That is, since it is very difficult to form a fullerene thin film by a vapor phase growth method, studies on the formation of a fullerene thin film by a wet film forming method such as a solvent casting method have been made (for example, see Non-Patent Document 1). .
In addition, fullerene has low solubility in a solvent and has a highly symmetrical spherical molecular structure and low orientation, so it has a sufficient film thickness, and fullerene molecules are regularly oriented. Is difficult to obtain by a wet casting method such as a solvent casting method, and various fullerene derivatives have been studied and various derivatives have been proposed in order to improve the film-forming properties of fullerene and the solubility in solvents. (For example, refer to Patent Document 2).

  In addition, the applicant of the present application can easily manufacture by a wet film-forming method, and can be mass-produced, can be retained without impairing the original properties of fullerene, and further, a decomposition product generated by thermal decomposition can generate a nitrogen compound at the decomposition temperature. As a method for producing a fullerene film capable of forming a homogenous fullerene film without polluting the production environment and not remaining in the film because it does not contain a gas, the thermal decomposition temperature is 400 ° C. or lower. And a coating film obtained by applying a fullerene derivative solution, which is a decomposition product generated by thermal decomposition, which is a gas containing no nitrogen compound at a decomposition temperature, on a substrate, is higher than the thermal decomposition temperature of the fullerene derivative. Heating at a temperature lower than the thermal decomposition temperature of the fullerene to thermally decompose at least a part of the fullerene derivative. It proposed a method for producing a fullerene film (Patent Document 3).

JP-A-64-31974 JP 2006-199674 A JP 2010-229021 A

Pavel Janda et al., “Advanced Materials” (Germany), Wiley-VCH Verlag, December 1998, Vol. 10, No. 17, p. 1434-1438

  An amorphous carbon film has high hardness and excellent various physical properties, but its formation method is limited to the dry film forming method, and is not suitable for industrial mass production and area enlargement.

  On the other hand, since fullerene is composed only of carbon, formation of a high-hardness fullerene film is expected. However, for film formation by a wet film formation method, various kinds of fullerene skeletons are added to improve the solubility in a solvent. It is necessary to introduce a substituent into a fullerene derivative. And by introducing a substituent, the carbon content of the fullerene derivative film to be formed is relatively reduced. As a result, a high hardness film cannot be formed.

  In Patent Document 3, the coating film of the fullerene derivative is heated at a temperature higher than the thermal decomposition temperature of the fullerene derivative and lower than the thermal decomposition temperature of the fullerene derivative, preferably 100 to 400 ° C, more preferably 150 to 300 ° C. Although at least a part of the fullerene derivative is thermally decomposed, it has been confirmed by the present inventors that it is difficult to obtain a high-hardness film by such low-temperature heat treatment.

  This invention is made | formed in view of the actual condition of the said prior art, and makes it a subject to provide the high hardness organic type carbon film which can be formed with a wet film forming method.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have conducted a heat treatment on a fullerene derivative film formed by a wet film-forming method in a high temperature region where fullerene decomposition starts, and a high-hardness organic carbon film Found that you can get.

  The present invention has been achieved based on such findings, and the gist thereof is as follows.

[1] An organic carbon film having a hardness evaluated by a pencil hardness method of 2H or more.

[2] The organic carbon film according to [1], which is obtained by heat-treating a film containing fullerene and / or fullerene derivatives at 400 ° C. or more and 1000 ° C. or less.

[3] fullerene of the fullerene and / or fullerene _{derivative, C 60, C 70, C} 76, C 82, C 84, and wherein the _{C 90} is at least one selected from fullerene [1] or The organic carbon film according to [2].

[4] The organic carbon film according to any one of [1] to [3], wherein the fullerene derivative has a structure represented by the following formula (1).

(In the above formula (1), FLN represents a fullerene skeleton, and R ¹ is represented by —Ar— (OX) _a or —Ar— (CH _(3-a) — (OX) _a ) _b. A substituent (wherein Ar is an aromatic hydrocarbon group which may have a substituent, O is an oxygen atom, X is a hydrogen atom or a protective group for an alcoholic hydroxyl group, a is an integer of 0 to 3, b is an integer of 1 to 5), R ² represents a hydrogen atom, a hydroxyl group or an organic group having 1 to 30 carbon atoms, m is an integer of 1 to 30, and n is an integer of 0 to 25. When m and n are 2 or more, the plurality of R ¹ and R ² may be different or the same.

[5] The organic carbon film according to any one of [1] to [3], wherein the fullerene derivative has a structure represented by the following formula (2).

(In the above formula (2), A represents a bonding site with the fullerene skeleton, and an oxygen atom, a sulfur atom, a phosphorus atom, a carbon chain having 1 to 6 carbon atoms, -Ar-O- (where Ar is a substituent) An aromatic hydrocarbon group which may have a bond to the fullerene skeleton), an optionally substituted cycloaliphatic group containing a carbon atom of the fullerene skeleton, or an optionally substituted aromatic R represents an integer of 0 to 6, t represents an integer of 0 or 1, p represents an integer of 1 to 3, q represents an integer of 1 to 46, and R ³ represents an integer of 1 to 20 carbon atoms. Represents an organic group of

[6] The binding site A with the fullerene skeleton of the formula (2) has a cyclic hydrocarbon structure containing a carbon atom on the fullerene skeleton represented by the following formula (3). The organic carbon film described.

(However, in the above formula (3), the two ^{C f} represents the two adjacent carbon atoms on the fullerene skeleton, x is an integer from 1 to 8 Note, methylene group -. _{(CH 2) x} - in At least one of the hydrogen atoms is substituted with — (CH ₂ ) _r —CO— (O) _t —R ³ represented by the formula (2).

[7] The organic carbon film according to any one of [1] to [3], wherein the fullerene derivative has a structure represented by the following formula (4a) or (4b).

(However, in the above formulas (4a) and (4b), R ^a and R ^b each independently represent a hydrocarbon group which may have an arbitrary substituent, and R ^a and R ^b represent R (A nitrogen-containing ring which may have an arbitrary substituent may be formed together with any of a carbon atom, a nitrogen atom, and an oxygen atom bonded to both ^a and R ^b .)

[8] The organic as described in any one of [1] to [3], wherein the fullerene derivative has a cyclic hydrocarbon structure containing a carbon atom on a fullerene skeleton represented by the following formula (7): Carbon film.

(However, in the above formula (7), two C ^f represent two adjacent carbon atoms on the fullerene skeleton, and C _α H _β has a substituent not shown in the formula (7). Represents a saturated or unsaturated hydrocarbon chain having α carbon atoms and β hydrogen atoms bonded to any of these carbon atoms, α is an integer from 1 to 8, and β is from 0 to 16 (When C _α H _β has two or more substituents, these may be bonded to each other to form a cyclic structure.)

[9] Organic carbon obtained by subjecting the film containing fullerene and / or fullerene derivative to a film thickness M ₁ when heated at 110 ° C. and then heat-treating the film at 400 ° C. or more and 1000 ° C. or less. thickness M ₂ of the membrane, characterized in that at 0.5M ₁ or more [2] to organic carbon film according to any one of [8].

[10] The fullerene and / or film obtained by heating the film at a 110 ° C. containing fullerene derivative has an absorption peak at 1460 cm ^-1 ± ^{5 cm -1} in the Raman spectrum, then membranes were 400 ° C. or higher, The organic carbon film according to any one of [2] to [9], wherein the absorption peak is not observed in a Raman spectrum of the organic carbon film obtained by heat treatment at 1000 ° C. or lower.

[11] A method for producing an organic carbon film, comprising heat-treating a film formed using a fullerene derivative solution at a temperature of 400 ° C. or higher and 1000 ° C. or lower.

[12] The method for producing an organic carbon film according to [10], wherein the temperature of the heat treatment is 430 ° C. or higher and 800 ° C. or lower.

[13] The organic carbon film according to any one of [1] to [10], wherein a film formed wet using a solution of a fullerene derivative is heat-treated at 400 ° C. or higher and 1000 ° C. or lower. Manufacturing method.

[14] A laminate in which the organic carbon film according to any one of [1] to [10] is formed on a substrate.

The organic carbon film of the present invention is a high-hardness film having a pencil hardness of 2H or more, and can be produced at low cost by heat-treating a film formed by a wet film-forming method using a fullerene derivative. The area can be easily increased.
The organic carbon film of the present invention can be applied to various applications as a high-hardness functional film that replaces the conventional amorphous carbon film.

It is a chart which shows the Raman spectrum of fullerene derivative "H200" used for this invention. It is a chart which shows the Raman spectrum of the "organic carbon film 2" corresponding to the comparative example of this invention. It is a chart which shows the Raman spectrum of the "organic carbon film 3" corresponding to the Example of this invention. It is a chart which shows the Raman spectrum of the "organic carbon film 5" corresponding to the Example of this invention. It is a chart which shows collectively the Raman spectrum of fullerene derivative "H351" used for this invention, and additive "WPAG618". It is a chart which shows the Raman spectrum of the "organic carbon film 22" corresponding to the comparative example of this invention. It is a chart which shows the Raman spectrum of the "organic carbon film 23" corresponding to the Example of this invention. It is a chart which shows the infrared absorption spectrum of fullerene derivative "H200" used for this invention. It is a chart which shows the infrared absorption spectrum of the "organic carbon film 5" corresponding to the Example of this invention.

Hereinafter, the present invention will be described in detail with reference to examples and the like, but the present invention is not limited to the following examples and the like, and can be arbitrarily modified and implemented without departing from the gist of the present invention.
In addition, when using the expression “to” in this specification, it is used as an expression including numerical values before and after that.
The organic carbon film of the present invention is a high hardness organic carbon film having a hardness evaluated by a pencil hardness method of 2H or more. Details of the method of measuring hardness by this pencil hardness method will be described in the section of Examples below.

  Although there is no restriction | limiting in particular as the manufacturing method of the organic type carbon film of this invention, It is preferable to manufacture by the wet film forming method, and especially the film | membrane formed by the wet film forming method using the solution of a fullerene derivative is 400 degreeC or more. It is preferably produced according to the method for producing an organic carbon film of the present invention, which is heat-treated at 1000 ° C. or lower.

[Fullerene derivative]
First, a fullerene derivative suitable for production of the organic carbon film of the present invention will be described.

<Fullerene skeleton>
“Fullerene” is a carbon cluster having a closed shell structure. The carbon number of fullerene is usually an even number of 60 to 130. Specific examples of fullerenes include C ₆₀ , C ₇₀ , C ₇₆ , C ₇₈ , C ₈₂ , C ₈₄ , C ₉₀ , C ₉₄ , C ₉₆ and higher carbon clusters having more carbons than these. Can do. Note that in this specification, a fullerene skeleton having i carbon atoms (where i represents an arbitrary natural number) is appropriately represented by a general formula “C _i ”.

  The “fullerene derivative” is a general term for compounds or compositions having a fullerene skeleton. That is, fullerene derivatives include those having a substituent on the fullerene skeleton, those containing a metal or a compound in the fullerene skeleton, and those having a complex formed with another metal atom or compound.

Although the fullerene skeleton of the fullerene derivative according to the present invention is not limited, at least one selected from C ₆₀ , C ₇₀ , C ₇₆ , C ₈₂ , C ₈₄ , and C ₉₀ is preferable, and C ₆₀ or C ₇₀ is particularly preferable. C ₆₀ is more preferred. Since C ₆₀ and C ₇₀ are obtained as the main product in the production of fullerenes, the advantage that is easily available. That is, the fullerene derivative according to the present invention is preferably a derivative of C ₆₀ or C ₇₀ or a mixture thereof, and more preferably a derivative of C ₆₀ .

<Fullerene derivative (I)>
Preferable examples of the fullerene derivative used in the present invention include those having a structure represented by the following formula (1) (hereinafter referred to as “fullerene derivative (I)”). This fullerene derivative (I) is preferable because it has high heat resistance and a high residual film amount when subjected to high-temperature treatment.

(In the above formula (1), FLN represents a fullerene skeleton, and R ¹ is represented by —Ar— (OX) _a or —Ar— (CH _(3-a) — (OX) _a ) _b. A substituent (wherein Ar is an aromatic hydrocarbon group which may have a substituent, O is an oxygen atom, X is a hydrogen atom or a protective group for an alcoholic hydroxyl group, a is an integer of 0 to 3, b is an integer of 1 to 5), R ² represents a hydrogen atom, a hydroxyl group or an organic group having 1 to 30 carbon atoms, m is an integer of 1 to 30, and n is an integer of 0 to 25. When m and n are 2 or more, the plurality of R ¹ and R ² may be different or the same.

The substituent R ¹ in the fullerene derivative (I) is easily removed by heat treatment to give an alkylol group, particularly when a = 1 in —Ar—CH 2 _(3-a) — (OX) _a . Therefore, the fullerene derivative (I) has R ¹ which is a self-reactive substituent and not only can obtain a condensate by intermolecular reaction, but also a crosslinking reaction proceeds when m ≧ 2. A cross-linked fullerene material can be obtained.
Moreover, fullerene derivative (I) can also couple | bond with the compound containing an alkylol group or a phenolic hydroxyl group other than fullerene derivative (I). In particular, when the substituent R ¹ in the fullerene derivative (I) is 2 or more (m = 2 or more in the formula (1)), it is used as a crosslinking agent for other fullerene derivatives containing an alkylol group or a phenolic hydroxyl group. You can also.

In the formula (1), m is the number of substituents R ¹ bonded to the fullerene skeleton. m is an integer of 1 to 30, preferably 5 to 20, and more preferably 5 to 10.
In addition, when m is 2 or more, each substituent R ¹ may have the same structure or a different structure. For example, when one kind of compound is used as a raw material, the structure has the same substituent. When a mixture of a plurality of compounds is used as a raw material, derivatives having different structures are usually obtained. A plurality of substituents can be introduced depending on the intended use.

In the fullerene derivative (I), the aromatic hydrocarbon group which may have a substituent of Ar contained in the substituent R ¹ is an aromatic carbon group having 6 to 18 carbon atoms which may have a substituent. A hydrogen group is preferred.

As a specific example of an aromatic hydrocarbon group having 6 to 18 carbon atoms that may have a substituent, when R ¹ is —Ar—CH 2 _(3-a) — (OX) _a , Is phenylene group, methylphenylene group, dimethylphenylene group, trimethylphenylene group, methoxyphenylene group, hydroxyphenylene group, dihydroxyphenylene group, hydroxymethylphenylene group, ethylhydroxyphenylene group, hydroxydimethylphenylene group, acetylphenylene group, phenylene fluoride Group, chlorophenylene group, bromophenylene group, t-butylphenylene group, ethylphenylene group, biphenylene group, naphthylene group, methylnaphthylene group, hydroxynaphthylene group, methoxynaphthylene group, anthracenylene group, phenanthracenylene group, Pyrenylene group etc. It is.
Among these, a phenylene group, a naphthylene group, or an anthracenylene group is preferable, and a phenylene group is particularly preferable.

When R ¹ is -Ar- (OX) _a , Ar is a phenyl group, a methylphenyl group, a dimethylphenyl group, a trimethylphenyl group, a methoxyphenyl group, a hydroxyphenyl group, a dihydroxyphenyl group, a hydroxymethylphenyl group, Ethyl hydroxyphenyl group, hydroxydimethylphenyl group, acetylphenyl group, fluorinated phenyl group, chlorophenyl group, bromophenyl group, t-butylphenyl group, ethylphenyl group, biphenyl group, naphthyl group, methylnaphthyl group, hydroxynaphthyl group, Examples include methoxynaphthyl group, anthracenyl group, phenanthracenyl group, pyrenyl group and the like.
Among these, a phenyl group, a naphthyl group, or an anthracenyl group is preferable, and a phenyl group is particularly preferable.

X is a hydrogen atom or a protecting group for an alcoholic hydroxyl group, preferably a hydrogen atom or a protecting group for an alcoholic hydroxyl group having 1 to 10 carbon atoms.
When X is a hydrogen atom or a protecting group for an alcoholic hydroxyl group having 1 to 10 carbon atoms, it can be easily removed by heating or the like, so that an alkylol group is generated at the terminal. The alkylol group has self-reactivity and can not only obtain a condensate by intermolecular reaction, but can also have crosslinkability when it has a plurality of substituents R ¹ (m ≧ 2). .

  Among the protecting groups for alcoholic hydroxyl groups, alkyl groups, aryl groups, silyl ether groups, acyl groups, aralkyl groups, or cyclic structures having 1 to 10 carbon atoms and optionally having an ether bond or thioether bond in the carbon chain. It is preferably a heterocyclic group having 5 to 12 atoms.

Specific examples of the alkyl group, aryl group, silyl ether group, acyl group, and aralkyl group having 1 to 10 carbon atoms and optionally having an ether bond or thioether bond in the carbon chain include a methyl group and an ethyl group. Methoxymethyl group, benzylmethyl group, benzyloxyalkyl group, trimethylsilyl group, acetyl group, benzoyl group, bivaloyl group and the like.
Specific examples of the heterocyclic group having 5 to 12 atoms constituting the cyclic structure include a tetrahydropyranyl group.
The protecting group for the alcoholic hydroxyl group is not particularly limited as described above, and known protecting groups are targeted. For example, THEODRA W. Protecting groups described in GREEN “PROTECTIVE GROUPS in ORGANIC SYNTHESIS” (WILEY-INTERSCIENCE THIRD EDITION) p23-200 are also effective.

  Among these, as X, a hydrogen atom is preferable, and when it is a protective group for an alcoholic hydroxyl group, a methyl group, a benzyl group, and a tetrahydropyranyl group are preferable, and a tetrahydropyranyl group is particularly preferable.

The fullerene derivative (I) may have a substituent R ² in addition to the substituent R ¹ .
The substituent R ² is a hydrogen atom, a hydroxyl group, or an organic group having 1 to 30 carbon atoms. Examples of the organic group include an alkyl group, an alkenyl group, an allyl group, and an aryl group. Also, n representing the number of substituents R ² bonded to the fullerene skeleton represented by the above formula (1) is an integer of 0 to 25, preferably 0 to 20, more preferably 0 to 15. When n is 2 or more, each R ² may be different or the same. Note that n = 0 indicates that the substituent R ² does not exist.

R ² is preferably a hydrogen atom or an alkyl or alkenyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms.

Among the fullerene derivatives (I), a fullerene derivative in which Ar of the substituent R ¹ is Ar—CH ₂ —OX in which Ar is a phenylene group is preferable.
Among such fullerene derivatives, it is particularly preferable that the fullerene skeleton is C ₆₀ or C ₇₀ , m is an integer of 5 to 10, and X is a hydrogen atom, a methyl group or a tetrahydropyranyl group.

  About the manufacturing method of fullerene derivative (I), the representative example is shown in the synthesis example 1 mentioned later.

<Fullerene derivative (II)>
Another preferred example of the fullerene derivative used in the present invention is one having a structure represented by the following formula (2) (hereinafter referred to as “fullerene derivative (II)”). This fullerene derivative (II) is preferable in that the synthesis method is simple.

(In the above formula (2), A represents a bonding site with the fullerene skeleton, and represents an oxygen atom, a sulfur atom, a phosphorus atom, a carbon atom chain having 1 to 6 carbon atoms, -Ar-O- (where Ar is a substituted group). An aromatic hydrocarbon group which may have a group and bonded to the fullerene skeleton.), An optionally substituted cycloaliphatic group containing a carbon atom of the fullerene skeleton, or an optionally substituted group. Represents an aromatic hydrocarbon group, r represents an integer of 0 to 6, t represents an integer of 0 or 1, p represents an integer of 1 to 3, q represents an integer of 1 to 46, and R ³ represents an integer of 1 to Represents 20 organic groups.)

When A in the formula (2) representing the fullerene derivative (II) is —Ar—O, the aromatic hydrocarbon group optionally having an Ar substituent is, in the formula (1), R ¹ is In the case of -Ar-CH _(3-a) -(OX) _a or -Ar- (OX) _a , those exemplified as Ar can be mentioned, and preferably a phenylene group or a naphthalene group.
Examples of the carbon atom chain having 1 to 6 carbon atoms represented by A include a divalent to tetravalent chain hydrocarbon chain, and among them, an alkylene group is preferable from the viewpoint of ease of synthesis.

  A in the fullerene derivative (II) preferably has an oxygen atom, -Ar-O-, or a cyclic hydrocarbon structure containing a carbon atom on the fullerene skeleton represented by the following formula (3).

(However, in the above formula (3), the two ^{C f} represents the two adjacent carbon atoms on the fullerene skeleton, x is an integer from 1 to 8 Note, methylene group -. _{(CH 2) x} - in At least one of the hydrogen atoms is substituted with — (CH ₂ ) _r —CO— (O) _t —R ³ represented by the formula (3).

In the formula (2), the number r of methylene chains is 0-6, but in order to dissolve in a high concentration in an ester solvent such as propylene glycol methyl acetate (hereinafter abbreviated as “PGMEA”), The preferable r is 4 or less. The number r of methylene chains is preferably 0 or 1 from the viewpoint of raw material procurement.
The methylene chain may be substituted with another organic group as long as the excellent physical properties of the fullerene derivative (II) are not significantly impaired.

In the formula (2), the number t of oxygen atoms represents 0 or 1, but t is preferably 1 from the viewpoint of improving the solubility in an ester solvent such as PGMEA.
Moreover, although p is an integer of 1-3, it is preferable that p is 1 or 2 when the synthetic | combination ease is considered.
Moreover, although q is an integer of 1-46, 1-10 are preferable from a soluble and heat resistant viewpoint, and 1-6 are especially preferable.

In formula (2), R ³ represents an organic group having 1 to 20 carbon atoms. R ³ preferably has 1 to 15 carbon atoms, and is preferably a linear or branched alkyl group having 1 to 10 carbon atoms from the viewpoint of raw material procurement.

Specific examples of R ³ include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, isopropyl group, sec-butyl group, iso-butyl group. , Tert-butyl group, tert-amyl group, neopentyl group, 2-methylbutyl group, 3-methylbutyl group and the like linear or branched chain alkyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclo Examples thereof include cyclic alkyl groups such as heptyl group, norbornyl group, tricyclodecanyl group and adamantyl group; alkenyl groups such as allyl group, crotyl group and cinnamyl group; and aryl groups such as phenyl group, biphenyl group and naphthyl group.

Furthermore, from the viewpoint of acid dissociation and thermal decomposability, R ³ is preferably an alkyl group in which the carbon atom to which the oxygen atom or carbonyl group is bonded is a tertiary carbon atom. Specifically, tert-butyl group, tert-amyl group, 1,1-diethylpropyl group, 1-methylcyclopentyl group, 1-methylcyclohexyl group, 1-ethylcyclopentyl group, 1-ethylcyclohexyl group, 1-butyl A cyclopentyl group, 1-butylcyclohexyl group, 2-methyl-2-adamantyl group and the like can be mentioned. Among these, the tert-butyl group is most preferable from the viewpoint that the decomposition product after the thermal decomposition is a gas.

These organic groups R ³ may be further substituted with other substituents as long as they do not significantly impair the excellent physical properties of the organic carbon film of the present invention. The substituent is not limited to a hydrocarbon group, and may be a substituent such as a halogen atom or a hydroxyl group. However, even if it has a substituent, the total number of carbon atoms including the substituent preferably satisfies the above conditions.

In addition, when A of the fullerene derivative (II) is an oxygen atom, r is preferably 1.
Further, when A of the fullerene derivative (II) is a group represented by the above formula (3), x is preferably a cyclopropyl group of 1, r is 0, and p is 2. preferable.

  Examples of preferable fullerene derivatives (II) include hydroxylated fullerenes, aromatic group-containing fullerenes, and cyclopropane ring-containing fullerenes represented by the following formulas (4) to (6).

(Fullerene hydroxide)

The fullerene derivative of the formula (4) is a fullerene derivative in which the binding site A to the fullerene skeleton is an oxygen atom in the partial structure represented by the formula (2), r represents an integer of 0 to 5, Represents 0 or 1, z and s represent z + s = q, that is, an integer in which the sum of z and s satisfies 1 to 46, and R ³ represents an organic group having 1 to 20 carbon atoms as in formula (2). Represents. This fullerene derivative is obtained by introducing an organic group having a specific structure onto a hydroxyl group of a fullerene hydroxide.

  In the formula (4), z represents the number of protected hydroxyl protecting groups bonded to the fullerene skeleton. S represents the number of unprotected hydroxyl groups bonded to the fullerene skeleton. As described above, z + s (= q) is an integer of 1 to 46, preferably 2 or more, more preferably 6 or more, particularly preferably 8 or more, preferably 20 or less, more preferably 12 or less. . The number of z + s corresponds to the number of hydroxyl groups of the fullerene hydroxide as a raw material, but an appropriate one may be selected according to the purpose.

If the value of z + s is too small, the solubility in an organic solvent tends to be low, and if it is too large, the properties of the fullerene derivative tend to be impaired.
In the formula (4), z is 1 or more and 46 or less, preferably 2 or more, more preferably 3 or more, preferably 20 or less, more preferably 10 or less.

Furthermore, in Formula (4), s is 0 to 45, preferably 20 or less, more preferably 10 or less.
z and s may be determined according to the number of hydroxyl groups (z + s) of the fullerene hydroxide used as a raw material and the purpose of introducing these substituents.

  In the formula (4), the number of hydroxyl protecting groups may be one, or two or more. In the case of two or more types, the combination and ratio are arbitrary.

(Aromatic group-containing fullerene)

The fullerene derivative of the formula (5) is a fullerene derivative in which the binding site A to the fullerene skeleton is —Ar—O— in the partial structure represented by the formula (2), and r is an integer of 0 to 5. T represents 0 or 1, y represents an integer of 1 to 15, and R ³ represents an organic group having 1 to 20 carbon atoms.

  This fullerene derivative is a fullerene derivative having an aromatic hydroxyl group described in JP-A No. 2006-56878, or a fullerene having an aromatic hydroxyl group obtained by allowing an aromatic compound having a hydroxyl group and aluminum trichloride to act on the fullerene. An organic group having a specific structure is introduced into the hydroxyl group of the derivative.

  In the formula (5), y represents the number of aromatic hydrocarbon groups bonded to the fullerene skeleton protected by an organic group having a specific structure. y is 1 or more and 15 or less, preferably 2 or more, more preferably 3 or more, and usually 15 or less, preferably 10 or less, more preferably 5 or less. y (the number of substitution with an aromatic hydrocarbon group) may be determined according to the number of hydroxyl groups and the purpose of the fullerene derivative used as a raw material.

  In addition, the fullerene derivative represented by the above formula (5) has an aromatic hydrocarbon group having an unprotected hydroxyl group represented by -Ar-OH in addition to the partial structure represented by the above formula (5). May be. The fullerene skeleton may have a hydrogen group (that is, a hydrogen atom, also referred to as a hydro group), an epoxide (that is, an oxide that forms a three-membered ring), or an organic group having 1 to 30 carbon atoms.

  In the formula (5), the organic group introduced into the aromatic hydroxyl group may be one type or two or more types. In the case of two or more types, the combination and ratio are arbitrary.

(Cyclopropane ring-containing fullerene)

In the fullerene derivative of the formula (6), in the partial structure represented by the formula (2), the binding site A with the fullerene skeleton represented by the formula (2) has two carbon atoms adjacent to the fullerene skeleton. A fullerene derivative which is a three-membered ring (cyclopropane ring) included, FLN represents a fullerene skeleton, r represents an integer of 0 to 5, t represents 0 or 1, p represents 1 or 2, q represents an integer of 1 to 46, and R ³ represents an organic group having 1 to 20 carbon atoms.

  As the fullerene derivative represented by the formula (6), methanofullerene derivatives described in Japanese Patent No. 3512412 and Japanese Patent Application Laid-Open No. 2005-26395 can be used. The methanofullerene is a kind of fullerene derivative and is a general term for a fullerene derivative having a cross-linking bond with a methylene group on the fullerene skeleton, and usually refers to a fullerene derivative having a cyclopropane structure on the fullerene skeleton.

In the above formula (6), r is preferably 0, t is preferably 1, and p is preferably 2. q corresponds to the number of bridged methylene groups added. The theoretical maximum value for C ₆₀ fullerene is 30, but the upper limit of t is usually lower than 30 due to factors such as steric repulsion.

  The fullerene derivative (II) represented by the fullerene derivatives represented by the above formulas (4) to (6) can be produced by the method described in JP 2010-229021 A.

<Fullerene derivative (III)>
Another preferred example of the fullerene derivative used in the present invention is an aminated fullerene derivative having a structure represented by the following formula (4a) or (4b). These are preferable in that the carbon concentration of the film can be increased because the additional group can be decomposed at a low temperature.

(However, in the above formulas (4a) and (4b), R ^a and R ^b each independently represent a hydrocarbon group which may have an arbitrary substituent, and R ^a and R ^b represent R (A nitrogen-containing ring which may have an arbitrary substituent may be formed together with any of a carbon atom, a nitrogen atom, and an oxygen atom bonded to both ^a and R ^b .)

In the formulas (4a) and (4b), examples of the hydrocarbon group which may have a substituent for R ^a and R ^b include an alkyl group, an aralkyl group, and an alkenyl group. Specifically, a methyl group , Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, cyclopropyl group, cyclopentyl group, benzyl group, phenethyl group, vinyl group, propenyl group, Examples thereof include an isopropenyl group, an allyl group, a butenyl group, a pentenyl group, and a hexenyl group. Of these, a methyl group is preferred because it is easy to synthesize.

In addition, R ^a and R ^b form a nitrogen-containing ring which may have an arbitrary substituent together with any of a carbon atom, a nitrogen atom and an oxygen atom bonded to both R ^a and R ^b. The nitrogen-containing ring structure includes structures corresponding to azetidine, pyrrolidine, imidazolidine, piperidine, piperazine, homopiperazine, pyrrole, pyrroline, imidazoline, imidazole, pyrazole, triazole, tetrazole, and the like, preferably piperidine Piperazine.

<Fullerene derivative (IV)>
As another preferred example of the fullerene derivative used in the present invention, a fullerene derivative having a cyclic hydrocarbon structure containing a carbon atom on the fullerene skeleton represented by the following formula (7) (hereinafter referred to as “fullerene derivative (IV)”). ). Fullerene derivative (IV) is preferable in that the synthesis is simple.

(However, in the above formula (7), two C ^f represent two adjacent carbon atoms on the fullerene skeleton, and C _α H _β has a substituent not shown in the formula (7). Represents a saturated or unsaturated hydrocarbon chain having α carbon atoms and β hydrogen atoms bonded to any of these carbon atoms, α is an integer from 1 to 8, and β is from 0 to 16 (When C _α H _β has two or more substituents, these may be bonded to each other to form a cyclic structure.)

The C _alpha H _beta in the formula (7) include _{-C (Q) H-CH 2} -C (Q) H -, - CH 2 -C (Q) = C (Q) -CH 2 -Etc. are mentioned. Here, Q is an arbitrary substituent bonded to a carbon atom, and a plurality of Q may be the same or different. Moreover, Qs may combine to form a cyclic structure.

Examples of the substituent Q include those exemplified as the organic group having 1 to 20 carbon atoms of R ³ in the above formula (2), and examples of the cyclic structure formed by combining these with each other include an indene ring and an indane ring. Benzene ring, benzocyclobutene ring, benzocyclohexane ring and the like.

  In addition, the number of cyclic hydrocarbon structures containing carbon atoms on the fullerene skeleton represented by the formula (7) of one fullerene derivative (IV) is preferably 1 to 16, and particularly preferably 1 to 10. .

  Specific examples of such fullerene derivatives (IV) include, for example, fullerene derivatives represented by the following structural formula (7a), fullerene derivatives represented by the following structural formula (7b), etc. w represents an integer of 1 to 10.)

<Other fullerene derivatives>
The raw material fullerene derivative used in the present invention is not particularly limited as long as an organic carbon film having a pencil hardness of 2H or more can be obtained by heat treatment. Besides the above fullerene derivatives, PCBM (phenyl C ₆₁ butyric acid methyl ester) Examples include polyadducts, hydroxylated fullerenes, and aminated fullerenes other than the aminated fullerenes represented by the above formulas (4a) and (4b).

  In addition, it is preferable that the fullerene derivative used by this invention satisfy | fills the below-mentioned suitable residual film rate, and it is preferable that it shows the below-mentioned specularity.

[Method for producing organic carbon film]
Next, a method for producing an organic carbon film of the present invention using the above fullerene derivative will be described. However, the method for producing an organic carbon film of the present invention is not limited to the method described below.

  In order to produce the organic carbon film of the present invention, first, a solution of the above-mentioned raw material fullerene derivative (hereinafter referred to as “film-forming solution” or “coating solution”) is prepared, and this film-forming solution is applied onto a substrate. A coating film is formed by wet film formation, and the coating film is dried as necessary, and then heat-treated at a predetermined temperature to obtain the organic carbon film of the present invention.

  In the production of the organic carbon film of the present invention, the raw material fullerene derivative may be used alone or in combination of two or more.

<Preparation of film forming solution>
The solvent used for the preparation of the film-forming solution is not particularly limited as long as the fullerene derivative has sufficient solubility and can be volatilized by heating at room temperature or under normal pressure or reduced pressure. However, it may be selected as appropriate in consideration of availability, price, toxicity or toxicity, safety, and the like.

  Examples of the solvent include monovalent or polyvalent alcohols, ketones, ethers, esters, aromatic hydrocarbons, aromatic halogenated hydrocarbons, heterocyclic compound solvents, alkane solvents, haloalkane solvents. , Acetonitrile, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), nitromethane, nitroethane, N-methyl-2-pyrrolidone (NMP) and water.

Examples of monovalent or polyhydric alcohols include methanol, ethanol, 1-propanol, 2-propanol, butanol, ethylene glycol, propylene glycol, diethylene glycol, glycerin, and dipropylene glycol.
Examples of ketones include acetone, MEK (methyl ethyl ketone), 2-heptanone, methyl isopropyl ketone, MIBK (methyl isobutyl ketone), and cyclohexanone (CHN).

Examples of ethers include dimethyl ether, diethyl ether, dibutyl ether, tetrahydrofuran (THF), and PGME (propylene glycol monomethyl ether).
Examples of ester solvents include ethyl acetate, butyl acetate, propyl acetate, ethyl lactate, GBL (γ-butyrolactone), PGMEA (propylene glycol monomethyl ether acetate), and the like.

Aromatic hydrocarbons include benzene, toluene, xylene, o-xylene, m-xylene, p-xylene, ethylbenzene, 1,2,3-trimethylbenzene, 1,3,5-trimethylbenzene, 1,2, 4-trimethylbenzene, 1-methylnaphthalene, 1-phenylnaphthalene and the like can be mentioned.
Specific examples of the aromatic halogenated hydrocarbons include chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, bromobenzene, 1,2,4-trichlorobenzene and the like.

Examples of the heterocyclic compound-based solvent include tetrahydrofuran, tetrahydrothiophene, 2-methylthiophene, pyridine, quinoline, thiophene, and the like.
Examples of alkane solvents include n-hexane, cyclohexane, n-octane, 2,2,4-trimethylpentane, n-decane, n-dodecane, n-tetradecane, decalin, cis-decalin, trans-decalin and the like. Can do.

  Examples of haloalkane solvents include dichloromethane, chloroform, carbon tetrachloride, 1,2-dibromoethane, trichloroethylene, tetrachloroethylene, dichlorodifluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1,1, 2,2-tetrachloroethane and the like can be mentioned.

  Among these solvents, examples of more preferably used solvents include PGMEA, PGME, ethyl lactate, 2-heptanone, CHN, MEK, GBL, NMP and the like.

  In the film forming solution, only one type of solvent may be used, or two or more types may be used in any combination.

  The concentration of the fullerene derivative in the film-forming solution varies depending on the solubility of the fullerene derivative in the solvent, the film thickness of the organic carbon film to be formed, and the like, but it is difficult to uniquely determine, but it is usually 1 to 30% by mass. Is preferable, it is more preferable that it is 5-30 mass%, and it is further more preferable that it is 10-25 mass%. If the fullerene derivative concentration in the film-forming solution is lower than 1% by mass, a large amount of solvent is required, which is uneconomical and it is necessary to repeatedly apply in order to form a thick organic carbon film. On the other hand, if the concentration of the organic carbon film exceeds 30% by mass, the viscosity of the film-forming solution becomes high and handling becomes difficult, and it becomes difficult to obtain an organic carbon film having a uniform film thickness. Further, in the film-forming solution, the fullerene derivative is preferably completely dissolved in the solvent, but may be suspended without being partially dissolved, or as long as it can be redispersed at the time of application to form a dispersion. , A part of it may be settled.

  Unless the excellent physical properties of the organic carbon film of the present invention are significantly impaired, the film forming solution may contain other additives in addition to the fullerene derivative and the solvent. Examples of the additive include a surfactant, a dispersant, a polymer compound, and the like, but are not limited thereto. The additive may contain only 1 type and may contain 2 or more types by arbitrary combinations and ratios.

  When the film-forming solution contains additives other than fullerene derivatives and solvents, if the additive content is too high, a high-hardness organic carbon film may not be obtained. Content is 30 mass% or less, and it is preferable to set it as 100 mass% or less, for example, 1-50 mass% with respect to a fullerene derivative. Further, the total solid content concentration of the fullerene derivative and the additive in the film forming solution is preferably 1 to 50% by mass, particularly preferably 10 to 40% by mass.

  As long as the fullerene derivative and additives used as necessary can be dissolved in the above-mentioned solvent, there is no limitation on the method for preparing the film-forming solution. It can be prepared by a method of irradiating. Moreover, there is no restriction | limiting in particular also in the mixing order of a fullerene derivative, a solvent, and the additive used as needed.

  The film-forming solution is usually prepared at room temperature (about 25 ° C.) from the viewpoint of stability and operability, but can be dissolved and stored while heating if it is not higher than the boiling point of the solvent. If there is no problem with the solubility of the fullerene derivative, it can be prepared and stored at a low temperature of 25 ° C. or lower.

<Wet film formation of film forming solution>
The wet film formation of the film forming solution can be performed by any method such as a dip coating method, a spin coating method, or a spray coating method.

  Examples of the shape of the substrate on which the film-forming solution is wet-formed include a plate shape, a film shape, a spherical shape, a lump shape, and a fibrous shape. Moreover, as a material of a base material, the thing of arbitrary materials can be used without being specifically limited unless thermal decomposition or a deformation | transformation is raise | generated at the time of the next heat processing. For example, a semiconductor such as glass or silicon, an inorganic material such as metal or concrete can be used.

  The film thickness of the coating film formed by wet film-forming of the film-forming solution is within the range of several nm to several tens of μm depending on the application etc. It can be adjusted appropriately. The lower limit of the film thickness is preferably 10 nm, more preferably 50 nm. The upper limit of the film thickness is theoretically not limited if wet film formation is repeated, but is preferably 1 μm, more preferably 500 nm. This film thickness can be measured by a known film thickness measuring method.

  If the coating film is too thick, the film quality may be deteriorated during the thermal decomposition of the fullerene derivative, and if it is too thin, there may be a problem of film heterogeneity such as pinholes.

<Drying process>
Prior to the heat treatment of the coating film, drying for removing the solvent remaining in the film may be performed.

Drying can be performed by any method depending on the boiling point, volatility, etc. of the solvent used. Examples of the drying method include air drying at room temperature and atmospheric pressure, vacuum drying at room temperature and reduced pressure, heating under atmospheric pressure and reduced pressure, and the like, which may be used in combination. In the case of drying by heating, it is preferable to carry out at 500 ° C. or less, preferably 300 ° C. or less, without destroying the closed shell structure of fullerene, and more preferably at 150 ° C. or less to prevent bumping of the coating film. . Furthermore, in order to suppress the change in the film quality due to oxidation, it may be performed in an inert atmosphere, but it can usually be performed in the air. In the case where drying by heating is performed under temperature conditions that do not involve destruction of the fullerene closed shell structure, drying may be performed simultaneously with the heat treatment described below. In the case of drying under reduced pressure, a preferable reduced pressure condition is 1.33 × 10 ² Pa (1 torr) or more and less than 1.01 × 10 ⁵ Pa (760 torr).

  Nitrogen, helium, argon etc. are mentioned as an inert gas which can be used when drying is performed in inert atmosphere.

  In particular, the coating film is preferably dried in the air at a temperature of 20 to 200 ° C. for about 5 seconds to 60 minutes.

<Heat treatment>
After the coating film formed by wet film formation of the film forming solution is dried as necessary, heat treatment is performed.

  In the present invention, the heat treatment is performed at a temperature of 400 ° C. or higher and 1000 ° C. or lower. When the heat treatment temperature is lower than 400 ° C., the intended high-hardness organic carbon film cannot be obtained. Even if the heat treatment temperature is higher than 1000 ° C., the improvement of the hardness of the organic carbon film obtained is not recognized, which is not preferable due to restrictions on the heat resistance of the base material, heating cost, heating equipment, and the like. The heat treatment is more preferably performed at a temperature exceeding 400 ° C., and particularly preferably performed at 430 to 800 ° C., particularly 450 to 650 ° C.

  The heat treatment time is not particularly limited as long as the target high-hardness organic carbon film can be obtained, but is usually 1 minute to 1 hour, preferably 1 minute to 0.5 hour.

  The atmosphere of the heat treatment may be an inert gas atmosphere similar to the dry atmosphere or in the air, but it is not preferable that the composition and properties of the organic carbon film obtained vary depending on the atmosphere. Therefore, it is necessary to consider this point.

<Residual film rate>
Organic material fullerene derivative used in the production of the carbon film of the present invention, with respect to the film thickness M ₁ upon heating the coating film formed by a wet film of the membrane forming solution described above at 110 ° C., then membranes were 400 ° C. As described above, the remaining film ratio M ₂ / M ₁ represented by the ratio of the film thickness M ₂ of the organic carbon film obtained by heat treatment at 1000 ° C. or less is preferably 0.5 or more. That is, M ₂ is preferably 0.5M ₁ or more.

  If the remaining film ratio is less than 0.5, the volume change rate is large and the film may have a low hardness due to the influence of a decrease in density or the like, and the film may have poor specularity. The remaining film ratio is preferably 0.5 or more, particularly preferably 0.6 or more, but is usually 0.95 or less in consideration of the influence of introduction of a substituent for obtaining a soluble fullerene derivative.

  In addition, the film thickness for calculating the remaining film ratio and the film thickness of the organic carbon film of the present invention described below can be obtained by measuring the level difference from the portion where the film is not applied.

<Film thickness>
The film thickness of the organic carbon film of the present invention is appropriately designed according to its use, but is usually 50 nm to 100 μm, particularly preferably 100 nm to 1 μm. If the film thickness of the organic carbon film is thinner than the above range, the film may disappear during the etching process when used as a carbon film material for semiconductors, for example. It can be difficult to make a uniform and high strength film.

<Specularity>
In the production of the organic carbon film of the present invention, it is preferable that the film surface has excellent specularity after the heat treatment of the coating film.
That is, when the decomposition of the fullerene derivative in the film proceeds non-uniformly by the heat treatment, the film surface after the heat treatment does not show a mirror surface and the film becomes rough. Organic carbon films with such film roughness usually have poor hardness and are not preferred for applications that require uniformity, such as for semiconductors.

  Note that the presence or absence of specularity of the film after the heat treatment can be evaluated by visual observation.

<Absorption peak of Raman spectrum>
In the present invention, a film (hereinafter referred to as “dry film”) obtained by heating a coating film formed by wet film-forming of the above-described film-forming solution at 110 ° C. is described in the Examples section below. When the Raman spectrum analysis is performed with the apparatus and conditions to be used, an absorption peak is confirmed in the vicinity of 1460 cm ⁻¹ (1460 cm ⁻¹ ± 5 cm ⁻¹ ). Thereafter, the dry film is heated at 400 ° C. or more and 1000 ° C. or less. When the obtained organic carbon film of the present invention is similarly subjected to Raman spectrum analysis, this absorption peak disappears.
The absorption peak near 1460 cm ⁻¹ is derived from the fullerene skeleton structure, and the absorption peak near 1460 cm ⁻¹ present in the dry film is not observed in the organic carbon film of the present invention. In the organic carbon film of the present invention obtained by heat-treating this dry film at a temperature of 400 ° C. or higher, at least a part of the fullerene skeleton of the fullerene derivative is decomposed, It is presumed to show that amorphous carbon or a structure close to this is taken, and the organic carbon film of the present invention is presumed to obtain high hardness.

[Pencil hardness]
The organic carbon film of the present invention is characterized in that the hardness evaluated by the pencil hardness method is 2H or more. The hardness is preferably as high as possible, more preferably 4H or more.

  With respect to the conventional amorphous carbon film, the pencil hardness measured by the pencil hardness method according to the present invention is about 6H, but according to the present invention, by appropriately controlling the type of fullerene derivative and the heat treatment temperature, An organic carbon film having a hardness of about 6H can also be obtained.

  In the present invention, the pencil hardness of the organic carbon film is a value evaluated by the following method.

<Evaluation of pencil hardness of organic carbon film>
For organic carbon films, JIS K-5600-5-4 General test method for coating materials-Part 5: Mechanical properties of coating film-Section 4: Method with following adjustment based on scratch hardness (pencil method) Then, the scratching operation is performed using a pencil with different hardness at a load of 630 g. When scratches deeper than about 1/10 of the evaluation film thickness occur with a probability of occurrence of 80% or more when scratched with a pencil, it is evaluated that scratches are generated with the pencil.
Even if the scratch depth is shallower than 1/10 of the evaluation film thickness even when scratched with a pencil, or the probability of occurrence is less than 80% even if the scratch depth is deeper than 1/10 of the evaluation film thickness The pencil is evaluated to be acceptable and the hardness of the pencil having the highest hardness is defined as the pencil hardness of the organic carbon film. The depth of the scratch is measured using an α step IQ (step difference measuring machine) (manufactured by KLA-Tencol).
In addition, the occurrence probability of scratches is obtained as a ratio of the number of evaluations made multiple times and the number of scratches divided by the number of evaluations.
In the evaluation, it is important that a uniform coating film is formed. In the evaluation using a non-uniform film, it is difficult to evaluate the essential physical properties of the organic carbon film of the present invention. Because there is, attention is necessary.

[Laminate]
The laminated body of the present invention is obtained by forming the organic carbon film of the present invention on the above-mentioned base material, and using the feature that the hardness of the surface of the organic carbon film is high, etching for the semiconductor described above It can be used for a substrate or the like.

  Hereinafter, the present invention will be described more specifically with reference to production examples and evaluation results of organic carbon films corresponding to examples and comparative examples. However, the present invention is limited by these examples as long as the gist thereof is not exceeded. Is not to be done.

In the following, abbreviations of various compounds and measurement methods are as follows.
THP: tetrahydropyranyl ODCB: o-dichlorobenzene THF: Tetrahydrofuran MeI: methyl iodide CDCl _3: deuterated chloroform PGMEA: Propylene glycol monomethyl ether acetate CHN: cyclohexanone ODS: octadecylsilyl Me: methyl Bu: butyl group Ph : Phenyl group BOC: tert-butoxycarbonyl group HPLC: High performance liquid chromatography NMR: Nuclear magnetic resonance MS: Mass spectrometry

  In the following, the film thickness of the organic carbon film was measured by an α step IQ (step difference measuring machine) (manufactured by KLA-Tencol).

[Synthesis of organic carbon film]
<Synthesis Example 1>
A THF suspension (75 mL) of copper (I) bromide (7.32 g, 51.0 mmol) was cooled to 5 ° C., and then the Grignard reagent synthesized from (4-THP) OCH ₂ —C ₆ H ₄ Br was used. A certain (4-THP) OCH ₂ —C ₆ H ₄ MgBr / THF solution (0.7 mol / L; 68 mL) was added, and the temperature was raised to 25 ° C. An ODCB solution (135 mL) of C ₆₀ (3.0 g, 4.17 mmol) was added thereto and stirred for 2 hours. To this, MeI (3.9 mL, 62.6 mmol) was added and further stirred for 8 hours. The reaction solution was filtered to remove THF, diluted with toluene, and subjected to silica column chromatography (developing solution: toluene and ethyl acetate). The solution is concentrated, crystallized with 2-propanol (500 mL), and vacuum dried at 100 ° C. to obtain a fullerene derivative: C ₆₀ {(4-THP) OCH ₂ —C ₆ H ₄ } ₅ (—CH ₃ ) As a product of an orange solid (6.01 g, 3.56 mmol, 84.5% yield).

The obtained product was measured by ¹ H-NMR and HPLC. ¹ H-NMR was measured at 400 MHz using CDCl ₃ as a solvent. For HPLC, a 0.5 mg / mL THF solution was prepared and measured under the following measurement conditions.

Column type: ODS
Column size: 150mm x 4.6mmφ
Eluent: Toluene / methanol = 4/6
Detector: UV290nm

  As a result of HPLC measurement, it was observed at 89.9 (Area%) at a retention time of 4.40 min.

Moreover, the measurement result of < ¹ > H-NMR was as follows.
_{^{<1 H-NMR (CDCl 3}} , 400MHz)>
7.78 ppm (d, Ph, 4H), 7.68 ppm (d, Ph, 4H), 7.30 ppm (t, Ph, 8H), 7.19 ppm (d, Ph, 2H), 7.06 ppm (d, Ph, 2H), 4.83~4.80ppm (m , PhCH 2, 4H), 4.70ppm (s, PhCH 2, 4H), 4.6ppm (m, PhCH 2, 2H), 4.5ppm (t , PhCH ₂ —O—CH, 4H), 4.3 ppm (d, PhCH ₂ —O—CH, 1H), 3.9 to 3.8 ppm (m, THP (O—CH ₂ ), 5H), 3. 6 to 3.5 ppm (m, THP (O—CH ₂ ), 5H), 2.0 to 1.4 ppm (m, C60Me + THP (CH ₂ ), 33H)

From the above results, it was confirmed that the obtained product was C ₆₀ {(4-THP) OCH ₂ —C ₆ H ₄ } ₅ (—CH ₃ ) represented by the following structural formula. This fullerene derivative is referred to as “H351”.

<Synthesis Example 2>
To a suspension of 1.0 g (1.12 mmol) of C ₆₀ (OH) ₁₀ in THF (20 mL) and acetone (40 mL) of fullerene hydroxide (average hydroxyl number 10) manufactured by Frontier Carbon Corporation, 8 g of potassium carbonate and 10 mL (68.2 mmol) of tert-butyl bromoacetate was added, and the mixture was stirred at 25 ° C. for 1 hour. Thereafter, the reaction solution was heated to 55 ° C. and further stirred for 12 hours. Thereafter, the reaction solution was filtered through Celite (developing solution: ethyl acetate), and the solvent was removed. Then, ethyl acetate and water were added to carry out a liquid separation operation. The organic phase is dried over sodium sulfate, filtered, and the solution is concentrated. Then, crystallization is performed with 300 mL of hexane, and vacuum drying is performed at 50 ° C., whereby a fullerene derivative: C ₆₀ (OH) _5.2 (O—CH ₂ C (= O) Ot-Bu) _4.8 was obtained as the product of a brown solid (0.74 g; 46% yield).

¹ H-NMR and MS measurement of the obtained product were performed. ¹ H-NMR was measured at 400 MHz using deuterated chloroform as a solvent.
^From the result of ¹ H-NMR measurement, a peak of 5.40 to 4.20 ppm (brs, O—CH ₂ —), 1.80 to 1.30 ppm (brs, tert-Bu) was observed at 9: 2. It was confirmed that a part of the hydroxyl groups of the fullerene hydroxide was protected.

After weighing each of the obtained product and coumarin as an internal standard, the mixture was dissolved in deuterated chloroform, and ¹ H-NMR was measured. The average molecular weight of the product obtained from each integration ratio was calculated to be 1437.2 and the average protection number was 4.8.
Moreover, in MS measurement of the obtained product, C ₆₀ (OH) ₆ (O—CH ₂ C (═O) Ot—Bu) ₂ : molecular weight 1084, C ₆₀ (OH) ₅ (O—CH ₂₎ C (═O) Ot-Bu) ₃ : molecular weight 1198, C ₆₀ (OH) ₄ (O—CH ₂ C (═O) Ot-Bu) ₄ : molecular weight 1312, C ₆₀ (OH) ₆ ( O—CH ₂ C (═O) Ot—Bu) ₄ : molecular weight 1346, C ₆₀ (OH) ₅ (O—CH ₂ C (═O) Ot—Bu) ₅ : molecular weight 1460, C ₆₀ ( OH) ₄ (O—CH ₂ C (═O) Ot—Bu) ₆ : molecular weight 1574, C ₆₀ (OH) ₆ (O—CH ₂ C (═O) Ot—Bu) ₆ : molecular weight 1608 , C ₆₀ (OH) ₅ (O—CH ₂ C (═O) Ot-Bu) ₇ : Molecular weight 1722 was observed as a mixture peak.
From the above results, it was confirmed that the obtained product was C ₆₀ (OH) _5.2 (O—CH ₂ C (═O) Ot—Bu) _4.8 represented by the following structural formula. This fullerene derivative is referred to as “D200-A”.

[Manufacture of organic carbon film]
<Organic carbon film 1-5>
A coating solution 1 was prepared by adding 6.7 parts by weight of PGMEA to 1 part by weight of a fullerene derivative “H200” (manufactured by Frontier Carbon Co., Ltd.) represented by the following structural formula.

Subsequently, the coating liquid 1 was dripped on the silicon wafer, and the coating liquid 1 was coated on the silicon wafer using a spin coater under the condition of rotating at 500 rpm for 10 seconds and then at 1500 rpm for 40 seconds.
Next, the silicon wafer coated with the coating liquid 1 is subjected to a heat treatment in air at 110 ° C. for 60 seconds (1st heat treatment) on a hot plate, followed by a heat treatment at the temperatures shown in Table 1 for 60 seconds (2nd heat treatment). Thus, organic carbon films 1 to 5 having the thicknesses shown in Table 1 were formed on the silicon wafer.

Moreover, in the said heat processing, the presence or absence of the mirror surface property of the coating film after each heat processing was visually observed and evaluated on the following reference | standard, and the result was shown in Table 1.
In Table 1, “NULL” in the “Additives” column indicates that no additive was used. The same applies to the following tables.

(Specularity evaluation criteria)
○: Mirror surface ×: Not mirror surface

  In addition, the thing which the film | membrane did not exist after heat processing was represented by "-".

<Organic carbon film 6-10>
A coating solution 2 was prepared by adding 6.7 parts by weight of PGMEA to 1 part by weight of a fullerene derivative “M100” (manufactured by Frontier Carbon Co., Ltd.) represented by the following structural formula.

  Except that the coating liquid 2 was used instead of the coating liquid 1, the organic carbon films 6 to 10 having the film thicknesses shown in Table 1 were formed in the same manner as the organic carbon films 1 to 5, respectively. The results are shown in Table 1.

<Organic carbon film 11-15>
A coating solution 3 was prepared by adding 5.7 parts by weight of CHN to 1 part by weight of fullerene derivative “H350” represented by the following structural formula.

  Except that the coating liquid 3 was used instead of the coating liquid 1, the organic carbon films 11 to 15 having the film thicknesses shown in Table 1 were formed in the same manner as the organic carbon films 1 to 5, respectively. The results are shown in Table 1.

<Organic carbon film 16-20>
A coating solution 4 was prepared by adding 5.7 parts by weight of CHN to 1 part by weight of the fullerene derivative “H351” represented by the following structural formula synthesized in Synthesis Example 1.

  Except that the coating liquid 4 was used instead of the coating liquid 1, the organic carbon films 16 to 20 having the film thicknesses shown in Table 1 were formed in the same manner as the organic carbon films 1 to 5, respectively. The results are shown in Table 1.

<Organic carbon films 21-25>
With respect to 1 part by weight of the fullerene derivative “H351” synthesized in Synthesis Example 1, 0.2 parts by weight of “WPAG618” (manufactured by Wako Pure Chemical Industries, Ltd.), which is a thermal acid generator, is added, and 5.7 parts by weight of CHN. Was added to prepare a coating solution 5.
Except that the coating solution 5 was used instead of the coating solution 1, the 2nd heat treatment temperature was set to the temperature shown in Table 1, and the organic system having the film thickness shown in Table 1 was used in the same manner as the organic carbon films 1 to 5. Carbon films 21 to 25 were formed, and the specularity was evaluated. The results are shown in Table 1.

<Organic carbon film 26-30>
A coating solution 6 was prepared by adding 11.5 parts by weight of PGMEA to 1 part by weight of polyhydroxystyrene (PHS resin) “VP15000” (manufactured by Nippon Soda Co., Ltd.).
Except that the coating liquid 6 was used instead of the coating liquid 1, the organic carbon films 26 to 30 having the film thicknesses shown in Table 2 were formed in the same manner as the organic carbon films 1 to 5, respectively. The evaluation was performed and the results are shown in Table 2.

<Organic carbon films 31-35>
Coating solution 7 was prepared by adding 7.3 parts by weight of PGMEA to 1 part by weight of novolak resin “SP1010” (manufactured by Asahi Organic Materials Co., Ltd.).
The organic carbon films 31 to 35 having the film thicknesses shown in Table 2 are formed in the same manner as the organic carbon films 1 to 5 except that the coating liquid 7 is used in place of the coating liquid 1, and each has a specularity. The evaluation was performed and the results are shown in Table 2.

<Organic carbon film 36-40>
A coating solution 8 was prepared by adding 4 parts by weight of PGMEA to 1 part by weight of a fullerene derivative “F301” (manufactured by Frontier Carbon Co.) represented by the following structural formula.

  Except that the coating liquid 8 was used instead of the coating liquid 1, the organic carbon films 36 to 40 having the film thicknesses shown in Table 2 were formed in the same manner as in the organic carbon films 1 to 5, respectively. The evaluation was performed and the results are shown in Table 2.

<Organic carbon films 41-45>
A coating solution 9 was prepared by adding 4 parts by weight of PGMEA to 1 part by weight of fullerene derivative “J204” (manufactured by Frontier Carbon Co.) represented by the following structural formula.

  The organic carbon films 41 to 45 having the film thicknesses shown in Table 2 are formed in the same manner as the organic carbon films 1 to 5 except that the coating liquid 9 is used instead of the coating liquid 1, and each has a specularity. The evaluation was performed and the results are shown in Table 2.

<Organic carbon film 46-50>
A coating solution 10 was prepared by adding 6.7 parts by weight of PGMEA to 1 part by weight of the fullerene derivative “D200-A” represented by the following structural formula synthesized in Synthesis Example 2.

  The organic carbon films 46 to 50 having the thicknesses shown in Table 2 are formed in the same manner as the organic carbon films 1 to 5 except that the coating liquid 10 is used in place of the coating liquid 1. The evaluation was performed and the results are shown in Table 2.

[Evaluation of hardness of organic carbon film]
As described above, the organic carbon film shown in Table 3 was based on JIS K-5600-5-4 General test method for coating materials-Part 5: Mechanical properties of coating film-Section 4: Scratch hardness (pencil method) The pencil hardness was evaluated by the correction method.
Table 3 shows the pencil hardness evaluation results corresponding to the 2nd heat treatment temperature of each organic carbon film.

  From Table 3, it can be seen that a high-hardness organic carbon film can be obtained by performing a heat treatment at 400 ° C. or higher on a coating film formed using a fullerene derivative.

[Residual film ratio before and after heat treatment]
The ratio of the film thickness M ₂ after the 2nd heat treatment to the film thickness M ₁ after the 1st heat treatment at the time of manufacturing the organic carbon film shown in Table 4 as the remaining film ratio before and after the heat treatment (M ₂ / M ₁ ) Table 4 shows the results corresponding to the 2nd heat treatment temperature of each organic carbon film.

[Raman spectrum analysis]
Fullerene derivatives H200 and H351 used as raw materials for organic carbon films, additives (thermal acid generator) WPAG618, and organic carbon films 2 (corresponding to comparative examples), 3 (corresponding to examples), 5 (examples) Equivalent), 22 (equivalent to Comparative Example), and 23 (equivalent to Example) were subjected to micro-Raman spectral analysis. The measurement results are shown in FIGS.
The measuring equipment and conditions are summarized in the table below.

1 and FIG. 5, in the fullerene derivatives H200 and H351, an absorption peak near 1460 cm ⁻¹ derived from the fullerene skeleton structure is observed (FIGS. 1 and 5), and this peak is the organic carbon film 2 (FIG. 2), It is also observed in Fig. 22 (Fig. 6). This suggests that the fullerene skeleton structure remains in these carbon films.
On the other hand, in the organic carbon film 3 (FIG. 3), 5 (FIG. 4), and 23 (FIG. 7), this peak becomes extremely small and is hardly observed.
This indicates that, in the present invention, at least a part of the fullerene skeleton of the fullerene derivative is decomposed by heat treatment at a temperature of 400 ° C. or higher, and amorphous carbon or a structure close thereto is obtained. It is presumed that the hardness of the film was improved.

[Infrared absorption (IR) spectrum analysis]
When the infrared absorption spectrum measurement of H200 and the organic carbon film 5 was performed, the appearance of a peak in the vicinity of 1730 cm ⁻¹ was confirmed (FIGS. 8 and 9).
From this, it was confirmed that the organic carbon film 5 is a film containing oxygen (carbonyl group).
As for the organic carbon film 5, the obtained film was peeled off, 1 mg of a sample was weighed, 199 mg of potassium bromide (KBr) was added thereto, and then pulverized and mixed in a mortar. And then IR measurement was performed.

Claims (14)

  An organic carbon film characterized by having a hardness evaluated by a pencil hardness method of 2H or more.   2. The organic carbon film according to claim 1, wherein the organic carbon film is obtained by heat-treating a film containing fullerene and / or a fullerene derivative at 400 ° C. or more and 1000 ° C. or less. Fullerene of the fullerene and / or fullerene _{derivative, C 60, C 70, C} 76, C 82, C 84, and claim 1 or claim 2, wherein the _{C 90} is at least one selected from fullerene The organic carbon film described in 1. The organic carbon film according to any one of claims 1 to 3, wherein the fullerene derivative has a structure represented by the following formula (1).

(In the above formula (1), FLN represents a fullerene skeleton, and R ¹ is represented by —Ar— (OX) _a or —Ar— (CH _(3-a) — (OX) _a ) _b. A substituent (wherein Ar is an aromatic hydrocarbon group which may have a substituent, O is an oxygen atom, X is a hydrogen atom or a protective group for an alcoholic hydroxyl group, a is an integer of 0 to 3, b is an integer of 1 to 5), R ² represents a hydrogen atom, a hydroxyl group or an organic group having 1 to 30 carbon atoms, m is an integer of 1 to 30, and n is an integer of 0 to 25. When m and n are 2 or more, the plurality of R ¹ and R ² may be different or the same. The organic carbon film according to any one of 1 to 3, wherein the fullerene derivative has a structure represented by the following formula (2).

(In the above formula (2), A represents a bonding site with the fullerene skeleton, and represents an oxygen atom, a sulfur atom, a phosphorus atom, a carbon atom chain having 1 to 6 carbon atoms, -Ar-O- (where Ar is a substituted group). An aromatic hydrocarbon group which may have a group and bonded to the fullerene skeleton.), An optionally substituted cycloaliphatic group containing a carbon atom of the fullerene skeleton, or an optionally substituted group. Represents an aromatic hydrocarbon group, r represents an integer of 0 to 6, t represents an integer of 0 or 1, p represents an integer of 1 to 3, q represents an integer of 1 to 46, and R ³ represents an integer of 1 to Represents 20 organic groups.) 6. The organic compound according to claim 5, wherein the binding site A to the fullerene skeleton of the formula (2) has a cyclic hydrocarbon structure containing a carbon atom on the fullerene skeleton represented by the following formula (3). Carbon film.

(However, in the above formula (3), the two ^{C f} represents the two adjacent carbon atoms on the fullerene skeleton, x is an integer from 1 to 8 Note, methylene group -. _{(CH 2) x} - in At least one of the hydrogen atoms is substituted with — (CH ₂ ) _r —CO— (O) _t —R ³ represented by the formula (2). The organic carbon film according to any one of 1 to 3, wherein the fullerene derivative has a structure represented by the following formula (4a) or (4b).

(However, in the above formulas (4a) and (4b), R ^a and R ^b each independently represent a hydrocarbon group which may have an arbitrary substituent, and R ^a and R ^b represent R (A nitrogen-containing ring which may have an arbitrary substituent may be formed together with any of a carbon atom, a nitrogen atom, and an oxygen atom bonded to both ^a and R ^b .) The organic carbon film according to any one of claims 1 to 3, wherein the fullerene derivative has a cyclic hydrocarbon structure containing a carbon atom on a fullerene skeleton represented by the following formula (7). .

(However, in the above formula (7), two C ^f represent two adjacent carbon atoms on the fullerene skeleton, and C _α H _β has a substituent not shown in the formula (7). Represents a saturated or unsaturated hydrocarbon chain having α carbon atoms and β hydrogen atoms bonded to any of these carbon atoms, α is an integer from 1 to 8, and β is from 0 to 16 (When C _α H _β has two or more substituents, these may be bonded to each other to form a cyclic structure.) A film of an organic carbon film obtained by heat-treating the film at 400 ° C. or more and 1000 ° C. or less with respect to the film thickness M ₁ when the film containing the fullerene and / or fullerene derivative is heated at 110 ° C. organic carbon film according to any one of claims 2 to 8 thickness M ₂ is characterized in that at 0.5M ₁ or more. The fullerene and / or film obtained by heating the film at a 110 ° C. containing fullerene derivative has an absorption peak at 1460 cm ^-1 ± ^{5 cm -1} in the Raman spectrum, then membranes were 400 ° C. or higher, 1000 ° C. or less The organic carbon film according to any one of claims 2 to 9, wherein the absorption peak is not observed in a Raman spectrum of the organic carbon film obtained by heat treatment with the method.   A method for producing an organic carbon film, comprising heat-treating a film formed using a fullerene derivative solution at a temperature of 400 ° C. or higher and 1000 ° C. or lower.   The temperature of the said heat processing is 430 degreeC or more and 800 degrees C or less, The manufacturing method of the organic carbon film of Claim 11 characterized by the above-mentioned.   The method for producing an organic carbon film according to any one of claims 1 to 10, wherein a film formed by a wet process using a solution of a fullerene derivative is subjected to a heat treatment at 400 ° C or higher and 1000 ° C or lower. .   A laminate comprising the organic carbon film according to any one of claims 1 to 10 formed on a substrate.

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