JP2009132640A - Fullerene derivative, its solution, and its membrane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fullerene derivative soluble to an alkoxybenzene solvent represented by anisole, a solution comprising the fullerene derivative, and a membrane comprising the fullerene derivative. <P>SOLUTION: Disclosed is a fullerene derivative that has solubility to anisole under a normal pressure and at a temperature of 25°C of not lower than 10% by weight and has a fullerene skeleton constituted of a partial structure represented by formula (I) wherein C<SP>1</SP>is bound to a hydrogen atom or an optional substituent and at least C<SP>6</SP>to C<SP>8</SP>are bound to, for example, an anisole structure. In formula (I), each of C<SP>1</SP>to C<SP>10</SP>represents a carbon atom that constitutes the fullerene skeleton. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel fullerene derivative, a solution thereof and a membrane thereof. Specifically, a fullerene derivative having, as a partial structure, an aromatic hydrocarbon group having 6 to 18 carbon atoms containing any one of an alkoxy group and an aryloxy group on the fullerene skeleton, and a solution containing the fullerene derivative And a film containing the fullerene derivative thereof.

Since the establishment of a large-scale synthesis method for C ₆₀ in 1990, research on fullerene has been vigorously developed. As a result, many fullerene derivatives have been synthesized and their various functions have been clarified. Along with this, various applications are being developed.

Among the fullerene derivatives, in particular, in the partial structure represented by the following formula (I) of the fullerene skeleton, a partial structure in which a substituent is added to three carbon atoms (for example, C ^{6 to} C ⁸ ) among C ^{6 to} C ¹⁰ ( Hereinafter, it may be referred to as “triple-added partial structure” as appropriate), or a partial structure in which substituents are added to all of C ^{6 to} C ¹⁰ (hereinafter referred to as “5-fold added partial structure” as appropriate). Various fullerene derivatives having) have been synthesized and reported.

(In the above formula (I), C ^{1 to} C ¹⁰ all represent carbon atoms constituting the fullerene skeleton.)

In the following description, the carbon atoms represented by C ^{1 to} C ¹⁰ of the partial structure represented by the above formula (I) may be simply represented by “C ¹ ” to “C ¹⁰ ”.
Furthermore, in the following description, a substituent bonded to C ^{6 to} C ¹⁰ in the above-described triple addition partial structure and / or five addition partial structure may be referred to as an “addition substituent”.

In addition, the fullerene derivative having the above-described triple addition partial structure and / or pentaaddition partial structure may be called according to the total number of additional substituents. According to this name, a fullerene derivative having one triple addition partial structure is a “triple addition fullerene derivative”, and a fullerene derivative having one five addition structure is a “5-addition fullerene derivative”. A fullerene derivative having two structures is a “6-addition fullerene derivative”, and a fullerene derivative having one triple-addition partial structure and one 5-addition partial structure is “8-addition fullerene derivative”. The two fullerene derivatives are “ten-added fullerene derivatives”.
In addition, fullerene derivatives having one or more of the above-described triple addition partial structure and / or five-fold addition partial structure are collectively referred to as “multiple addition fullerene derivative”.

Of 5 polyaddition fullerene derivative, for example, 5 polyaddition fullerene derivative C ₆₀ backbone is adapted to π-electron conjugated 50 electron system, different stereoisomeric the C ₆₀ unsubstituted which is π-electron conjugated 60 electron system It has configuration and electronic properties.

In addition, as a triple addition fullerene derivative having a smaller number of substituents than a five addition fullerene derivative, for example, a triple addition C ₇₀ derivative which is a π-electron conjugate of 66 electrons has been synthesized and reported. These triple addition fullerene derivatives have different physical properties from not only unsubstituted C ₆₀ and C ₇₀ but also the above five addition C ₆₀ derivatives. For these reasons, each fullerene derivative is expected as a new electron conductive material, semiconductor, physiologically active substance, and the like.

Multi-addition fullerene derivatives such as a 5-addition C ₆₀ derivative and a 3-addition C ₇₀ derivative have a unique structure in which an organic group is intensively added to a specific site of the fullerene and have a long π-electron conjugation. Therefore, various industrial uses are expected due to its electrochemical properties.

By the way, in order to use fullerene derivatives for electronic materials and optical materials, it is preferable that fullerene derivatives exhibit high solubility in organic solvents.
Some polyaddition fullerene derivatives have been developed that are soluble in aromatic hydrocarbon solvents such as toluene, halogen solvents such as chloroform, cyclic ethers such as tetrahydrofuran, etc. (See Patent Document 2).

  On the other hand, although it is an example of application, performances such as etching resistance of resist compositions using fullerenes and fullerene derivatives have been improved (see Patent Document 1, Non-Patent Document 3, and Non-Patent Document 4).

JP-A-10-282649 Chem. Lett. , 33, 328, 2004 J. et al. Organomet. Chem. , 599, 32-36, 2000 Jpn. J. et al. Appl. Phs. Vol. 39 (2000) pp. L1068-1070 Jpn. J. et al. Appl. Phs. Vol. 40 (2001) pp. L478-480

  However, the fullerenes and fullerene derivatives described in the above-mentioned documents have low solubility. Therefore, in preparing a resist composition, only solvents that have many problems in terms of industrial processing cost and safety, such as monochlorobenzene and orthodichlorobenzene, can be used. Tended to be difficult to apply.

For example, in Patent Document 1, Non-Patent Document 3, and Non-Patent Document 4, a positive electron beam resist ZEP520 manufactured by Zeon Corporation is used. ZEP520 is an orthodichlorobenzene solvent, and can contain fullerenes.
However, ZEP520A, in which the solvent is changed, is currently used for anisole, which is a highly safe solvent. ZEP520A tended to be insufficiently blended because of the low solubility of fullerenes.
For these reasons, a fullerene derivative having solubility in an alkoxybenzene solvent typified by anisole has been desired.

  Non-Patent Document 2 discloses a fullerene derivative to which a methoxyphenyl group having an anisole structure is bonded. However, this fullerene derivative has low solubility in an alkoxybenzene solvent typified by anisole and is used for the above applications. It tended to be difficult.

  The present invention has been made in view of the above-described problems. That is, the present invention is a multiple addition fullerene derivative having a specific aromatic hydrocarbon group as an addition substituent, and contains a fullerene derivative having solubility in an alkoxybenzene solvent typified by anisole, and the fullerene derivative. An object is to provide a solution and a film containing the fullerene derivative.

  As a result of the intensive studies by the inventors to solve the above problems, a partial structure of an aromatic hydrocarbon group having 6 to 18 carbon atoms containing any one of an alkoxy group and an aryloxy group on the fullerene skeleton is provided. By introducing it, a fullerene derivative having solubility in an alkoxybenzene solvent typified by anisole was developed and the present invention was completed.

That is, the gist of the present invention is that the solubility in anisole at an atmospheric pressure of 25 ° C. is 10% by weight or more, and in the partial structure represented by the following formula (I) of the fullerene skeleton, C ¹ is a hydrogen atom or an arbitrary The fullerene derivative is bonded to a substituent, and at least C ^{6 to} C ⁸ are each independently bonded to an organic group having a structure represented by the following formula (II) (Claim 1). .

(In the formula (I), C ^{1 to} C ¹⁰ all represent carbon atoms constituting the fullerene skeleton.)
(In the formula (II), Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, and R represents an alkyl group or an aryl group which may have a substituent.)

  At this time, it is preferable that Ar in the formula (II) is a hydrocarbon group having a naphthalene skeleton.

  The organic group having the structure represented by the formula (II) is preferably represented by the following formula (III).

(In the formula (III), X represents an organic group or a halogen atom before the third period, and m represents an integer of 1 or more and 4 or less, provided that when m is 2 or more, X is the same type. Or different types.)

  Moreover, it is preferable that R in said Formula (II) is a C1-C6 alkyl group (Claim 4). Especially, it is preferable that R in the said formula (II) is a methyl group (Claim 5).

In addition, it is preferable that C ^{6 to} C ¹⁰ in the formula (I) are independently bonded to an organic group having a structure represented by the formula (II).

Also, C ¹ in the above formula (I) is preferably bonded with an organic group having 1 to 30 carbon atoms (Claim 7).

Also, C ¹ in the formula (I) is preferably bonded with a methyl group (claim 8).

Further, C ¹ in the formula (I) is preferably bonded to an alkenyl group (claim 9).

The fullerene skeleton is preferably fullerene C ₆₀ (claim 10).

  Another gist of the present invention resides in a fullerene derivative solution, wherein the fullerene derivative is dissolved in a solvent.

  At this time, the solvent is preferably alkoxybenzene.

  Still another subject matter of the present invention lies in a fullerene derivative film containing the above-mentioned fullerene derivative (claim 13).

  According to the present invention, a fullerene derivative having solubility in an alkoxybenzene solvent typified by anisole, a solution containing the fullerene derivative, and a film containing the fullerene derivative are provided.

  Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and can be arbitrarily modified and implemented without departing from the scope of the invention.

[1. Fullerene derivative]
In the present invention, “fullerene” is a carbon cluster having a closed shell structure. The carbon number of fullerene is usually an even number of 60 or more and 130 or less.

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 carbon than these. It is done.
In the present specification, a fullerene skeleton having i carbon atoms (where i represents an arbitrary natural number) is appropriately represented by the 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 inside the fullerene skeleton, and those having a complex formed with another metal atom or compound. .

[1-1. Fullerene Derivative Structure]
The fullerene derivative of the present invention is a fullerene derivative having a specific partial structure.
The fullerene skeleton of the fullerene derivative of the present invention is not limited, but among them, C ₆₀ or C ₇₀ is preferable, and C ₆₀ is more preferable. 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 of the present invention is preferably a derivative of C ₆₀ or C _70, and more preferably a derivative of C _60.

In the fullerene derivative of the present invention, in the partial structure represented by the following formula (I) of the fullerene skeleton, C ¹ is bonded to a hydrogen atom or an arbitrary substituent, and at least C ^{6 to} C ⁸ are each independently represented by the following formula: It is combined with an organic group having a structure represented by (II). In the following description, the hydrogen atom and substituent bonded to C ¹ are collectively referred to as “R ¹⁰ ” as appropriate. Further, an organic group having a structure represented by the following formula (II) is appropriately referred to as “R ²⁰ ”.

(In the formula (I), C ^{1 to} C ¹⁰ all represent carbon atoms constituting the fullerene skeleton.)

(In the formula (II), Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, and R represents an alkyl group or an aryl group which may have a substituent.)

<About the hydrogen atom and substituent (R ¹⁰ ) bonded to C ¹ >
Hereinafter, the group bonded to C ¹ (namely, R ¹⁰ ) will be described in detail.
In the formula (I), C ¹ is bonded to a hydrogen atom or an arbitrary substituent (that is, R ¹⁰ ). There is no limitation on the type of the substituent, provided that it does not significantly impair the excellent physical properties of the fullerene derivative of the present invention.

When R ¹⁰ is a substituent, examples thereof include a halogen atom, an organic group, and other substituents.

(Halogen atom)
When R ¹⁰ is a halogen atom, specific examples thereof include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, a chlorine atom and a bromine atom are preferable because of ease of production.

(Organic group)
When R ¹⁰ is an organic group, specific examples thereof include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, isopropyl, sec- Linear or branched chain alkyl group such as butyl group, iso-butyl group, tert-butyl group, tert-amyl group, 2-methylbutyl group, 3-methylbutyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, Cyclic alkyl groups such as cyclohexyl group; alkenyl groups such as allyl group, crotyl group, cinnamyl group; aralkyl groups such as benzyl group, p-methoxybenzyl group, phenylethyl group; phenyl group, biphenyl group, naphthyl group, anthracenyl group, Aryl groups such as toluyl groups; alkoxy groups such as methoxy groups and ethoxy groups; phenoxy groups and the like Aryloxy group; substituted amino group such as monomethylamino group, dimethylamino group, monodiethylamino group, diethylamino group; methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, isopropoxycarbonyl group, butoxycarbonyl group, tert-butoxycarbonyl group, etc. Aryloxycarbonyl group; 5-membered heterocyclic group such as thienyl group, thiazolyl group, isothiazolyl group, furyl group, oxazolyl group, isoxazolyl group, pyrrolyl group, imidazolyl group, pyrazolyl group; pyridyl group, pyridazyl group, 6-membered heterocyclic groups such as pyrimidyl group, pyrazyl group, piperidyl group, piperazyl group, morpholyl group; thiocarbonyl groups such as thioformyl group, thioacetyl group, thiobenzoyl group; trimethylsilyl group, dimethyl group Substitution of rusilyl group, monomethylsilyl group, triethylsilyl group, diethylsilyl group, monoethylsilyl group, triisopropylsilyl group, diisopropylsilyl group, monoisopropylsilyl group, triphenylsilyl group, diphenylsilyl group, monophenylsilyl group, etc. A silyl group etc. are mentioned.

When R ¹⁰ is an organic group, the organic group may further have another substituent as long as the excellent physical properties of the fullerene derivative of the present invention are not significantly impaired. Examples of the substituent that the organic group of R ¹⁰ may have include an alkyl group, an alkenyl group, an aryl group, an alkoxy group, a hydroxyl group (hydroxy group), an amino group, a carboxyl group, an alkoxycarbonyl group, a halogen atom, and the like. Is mentioned. In addition, these substituents may be further substituted in multiple by one or more substituents. In addition, when it has a substituent, it is preferable that all the carbon numbers including the carbon number of a substituent satisfy | fill the range of the following carbon number.

Further, when R ¹⁰ is an organic group, the number of carbon atoms is arbitrary as long as the effects of the present invention are not significantly impaired, but usually 1 or more, usually 30 or less, preferably 20 or less, more preferably 10 or less. is there. When R ¹⁰ further has a substituent, the carbon number including the substituent preferably satisfies the above range. If the number of carbon atoms is too large, it may be difficult to bond to the fullerene skeleton.

(Other substituents)
When R ¹⁰ is another substituent, specific examples thereof include a hydroxyl group (hydroxy group), an amino group, a mercapto group, a carboxyl group, a cyano group, a silyl group, and a nitro group.

(Preferable example as R ¹⁰ )
Preferable groups as R ¹⁰ include hydrogen atom; halogen atom; alkyl group such as methyl group, ethyl group and propyl group; alkenyl group such as allyl group, crotyl group and cinnamyl group. Among them, R ¹⁰ is more preferably an alkyl group from the viewpoint of ease of synthesis and oxidation resistance, and a methyl group is particularly preferable from the viewpoint of thermal stability and cost. In addition, an alkenyl group is preferable from the viewpoint of ease of synthesis and improvement in solubility, and an allyl group, crotyl group, and cinnamyl group are particularly preferable from the viewpoint of cost.

Incidentally, R ¹⁰ is, in the fullerene derivatives per molecule, may be substituted each alone, or two or more of these may be substituted in optional ratio and combination.

<About the organic group (R ²⁰ ) having a structure represented by the formula (II)>
Hereinafter, the organic group having a structure represented by the formula (II) (that is, R ²⁰ ) will be described in detail.
R ²⁰ is an organic group having a structure represented by the above formula (II). In the formula (II), one OR group is bonded to the aromatic hydrocarbon group Ar.

(About R)
O in the OR group in the formula (II) is an oxygen atom. R in the OR group represents an alkyl group, aryl group or alkenyl group which may have a substituent. Of these, an alkyl group and an aryl group are preferable.
Specific examples of R include methyl, ethyl, propyl, butyl, pentyl, hexyl, isopropyl, sec-butyl, iso-butyl, tert-butyl, tert-amyl, 2- Linear or branched chain alkyl groups such as methylbutyl group and 3-methylbutyl group; cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group and cyclohexyl group; alkenyl groups such as allyl group, crotyl group and cinnamyl group Aralkyl groups such as benzyl group, p-methoxybenzyl group and phenylethyl group; aryl groups such as phenyl group, biphenyl group, naphthyl group, anthracenyl group and toluyl group; Among these, from the viewpoint of obtaining raw materials and improving etching resistance, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is particularly preferable.

  Moreover, said R may have another substituent, unless the outstanding physical property of the fullerene derivative of this invention is impaired significantly. Examples of the substituent that R may have include an alkyl group, an alkenyl group, an aryl group, an alkoxy group, a hydroxy group, an amino group, a carboxyl group, an alkoxycarbonyl group, and a halogen atom. In addition, these substituents may be further substituted in multiple by one or more substituents. One of these substituents may be substituted alone, or two or more may be substituted in any ratio and combination.

  When R is an alkyl group, the number of carbon atoms is not particularly limited as long as it is usually 1 or more, and it is usually 6 or less, preferably 4 or less. In addition, when R has a substituent, it is preferable that carbon number of the whole R including the carbon number of a substituent exists in the said range.

The number of OR groups bonded to the aromatic hydrocarbon group Ar is preferably one from the viewpoint of improving etching resistance.
Further, the position of the bond between the OR group and the aromatic hydrocarbon group Ar is arbitrary as long as the effects of the present invention are not significantly impaired.
Furthermore, when a substituent other than the OR group is bonded to the aromatic ring in Ar, the relative positional relationship between the OR group and the substituent is arbitrary as long as the effects of the present invention are not significantly impaired.
For example, when the hydrocarbon group is a naphthylene group, from the viewpoint of raw material procurement, it is bonded to the fullerene skeleton at the amphi position, that is, β-position (2-position), and the OR group is bonded to the 6-position of the naphthylene group. Is preferred. With respect to other hydrocarbon groups, preferred bonding positions can be determined from the above viewpoint.

(About Ar)
The carbon number of the aromatic hydrocarbon group Ar is usually 6 or more, and usually 18 or less, preferably 12 or less, more preferably 10 or less. When there are too many carbon atoms, there exists a tendency for the acquisition of a raw material to become difficult.

  The number of aromatic rings contained in the aromatic hydrocarbon group Ar is usually 1 or more, and usually 4 or less, preferably 2 or less. If the number of aromatic rings is too small, the conjugation does not extend and the extinction coefficient becomes high at a wavelength of 193 nm, so there is a possibility that it cannot be used in applications requiring transparency, and if it is too large, it tends to be difficult to obtain raw materials. is there.

As such aromatic hydrocarbon group Ar, for example, a hydrocarbon group having a benzene ring skeleton, a hydrocarbon group having a naphthalene skeleton, and the like are preferable, but not limited thereto.
Specific examples thereof include: phenylene group; vinylphenylene group such as vinylphenylene group, divinylphenylene group, trivinylphenylene group; pentalenylene group, indenylene group, naphthylene group, azlenylene group, heptalenylene group, biphenylenylene group, as -Indasenylene group, s-indacelenylene group, acenaphthyleneylene group, fluorenylene group, phenalelenylene group, phenanthrenylene group, anthracenylene group, fluoracenylene group, acephenanthyleneylene group, aceantirenylene group, triphenylenylene group, Examples thereof include condensed polycyclic hydrocarbon groups such as a pyrenylene group, a chrysenylene group, and a tetrasenylene group. Among these, a phenylene group, a naphthylene group, an anthracenylene group, a phenalenylene group, and a pyrenylene group are preferable from the viewpoint of raw material procurement, and a phenylene group and a naphthylene group are particularly preferable from the viewpoint of ease of synthesis.

  Further, the hydrocarbon group Ar having aromaticity may be a hydrocarbon group further having a substituent. For example, when Ar is a phenylene group, the structure represented by the above formula (II) is preferably a structure represented by the following formula (III) in order to enhance the solubility in alkoxybenzene. In the following formula (III), the Ar group has a substituent X in addition to the OR group.

(In the formula (III), X represents an organic group or a halogen atom before the third period, and m represents an integer of 1 or more and 4 or less, provided that when m is 2 or more, X is the same type. Or different types.)

  In the formula (III), m represents the number of X bonded to the phenyllene group, and specifically represents an integer of 1 or more and 4 or less. Among these, 2 or less is preferable from the viewpoint of raw material procurement. That is, m is preferably 1 or 2.

The substituent X in the formula (III) represents an organic group or a halogen atom before the third period.
Examples of X include an organic group such as 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, linear or branched chain alkyl group such as iso-butyl group, tert-butyl group, tert-amyl group, 2-methylbutyl group, 3-methylbutyl group; cyclopropyl group, cyclopentyl group, cyclobutyl group, cyclohexyl group, etc. Cyclic alkyl groups of the above; alkenyl groups such as allyl groups; aryl groups such as phenyl groups, biphenyl groups, and naphthyl groups.
Moreover, chlorine and fluorine are mentioned as a halogen atom before the 3rd period.
Among these, from the viewpoint of raw material procurement, an alkyl group and a halogen atom before the third period are preferable, and a methyl group, chlorine, and fluorine are particularly preferable.
When the number of substitutions m in the formula (III) is 2 or more, Xs may be the same type or a combination of different types.

  Furthermore, in the formula (III), the position where X is bonded to the phenylene group is arbitrary. When a plurality of X are bonded to the phenylene group, the positional relationship of each group is arbitrary, including the position of the OR group.

<Binding positions of R ¹⁰ and R ²⁰ in the partial structure represented by the formula (I)>
In the fullerene derivative of the present invention, at least C ^{6 to} C ^{8 in the} formula (I) are each independently bonded to an organic group having a structure represented by the above formula (II) (that is, R ²⁰ ). From the viewpoint of enhancing the solubility, it is desirable that not only C ^{6 to} C ⁸ but also all of C ^{6 to} C ¹⁰ are independently bonded to R ²⁰ .

The position of the bond with the fullerene skeleton in R ²⁰ is arbitrary as long as the effects of the present invention are not significantly impaired. For example, when the hydrocarbon group is a naphthylene group, it is preferably bonded at the β-position from the viewpoint of raw material procurement and ease of synthesis. With respect to other hydrocarbon groups, preferred bonding positions can be determined from the above viewpoint.

In the present specification, C ^{1 of} formula (I) is bonded to a hydrogen atom or an organic group (that is, R ¹⁰ ), and C ^{6 to} C ⁸ are each independently an organic group having a structure represented by formula (II) ( That is, the partial structure bonded to R ²⁰ ) may be referred to as “the triple addition partial structure of the present invention”. In addition, C ¹ in the formula (I) is bonded to a hydrogen atom or an organic group (that is, R ¹⁰ ), and C ^{6 to} C ¹⁰ are each independently an organic group (that is, R in the structure represented by the formula (II)). ²⁰ ) may be referred to as “the 5-addition partial structure of the present invention”.

Examples of the fullerene derivative of the present invention are listed below. However, the fullerene derivative of the present invention is not limited to the examples given below.
A triple addition fullerene derivative represented by the formula C _i (R ²⁰ ) ₃ (R ¹⁰ ) having one triple addition partial structure of the present invention on the fullerene skeleton.
· On the fullerene skeleton having one five-fold additional partial structure of the present invention, 5 polyaddition fullerene derivative represented by the formula ^{_{C i (R 20) 5 (}} R 10).
- triple additional partial structure of the present invention on the fullerene skeleton having two, 6 polyaddition fullerene derivative represented by the formula ^{_{C i (R 20) 6 (}} R 10) 2.
An octaaddition fullerene represented by the formula C _i (R ²⁰ ) ₈ (R ¹⁰ ) ₂ having one triple addition partial structure of the present invention and one pentaaddition partial structure of the present invention on the fullerene skeleton Derivative.
A 10-fold addition fullerene derivative represented by the formula C _i (R ²⁰ ) ₁₀ (R ¹⁰ ) ₂ having two 5-addition partial structures of the present invention on the fullerene skeleton.

Among these, as the fullerene derivative of the present invention, a pentaaddition fullerene derivative represented by the formula C _i (R ²⁰ ) ₅ (R ¹⁰ ) having one pentaaddition partial structure of the present invention on the fullerene skeleton. It is preferable because it is easy to manufacture.

  In the fullerene derivative of the present invention, the partial structure of the above formula (I) may be a structure observed from the inside of the closed shell structure of the fullerene skeleton or a structure observed from the outside. In other words, when a fullerene derivative is observed from the inside or outside of the closed shell structure of the fullerene skeleton, if at least one of the triple addition partial structure and / or the pentaaddition partial structure of the present invention is present, the present invention It corresponds to the fullerene derivative.

[1-2. Properties of fullerene derivatives]
The fullerene derivative of the present invention has high solubility in alkoxybenzene typified by anisole. In the present invention, that the fullerene derivative is “soluble in alkoxybenzene” means that the precipitate or insoluble matter is not visually detected after mixing the fullerene derivative with alkoxybenzene and applying ultrasonic irradiation for 10 minutes. Means that.
Specifically, the fullerene derivative is preferably dissolved at 50 mg or more, more preferably 75 mg or more, particularly preferably 100 mg or more per unit volume (1 mL) of anisole solvent with respect to anisole at 25 ° C. and normal pressure. The fullerene derivative is “highly soluble” in an organic solvent.

  When the fullerene derivative of the present invention is used after being dissolved in alkoxybenzene, the type of alkoxybenzene is not limited as long as the fullerene derivative of the present invention is dissolved. Specific examples of alkoxybenzene include methylphenyl ether (anisole), 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, ethylphenyl ether, propylphenyl ether, n-butylphenyl ether, and the like.

Among these, methoxybenzene is preferable from the viewpoint of cost and boiling point, and anisole is particularly preferable.
In addition, as for alkoxybenzene, only any 1 type may be used and 2 or more types may be used together by arbitrary combinations and a ratio.

These alkoxybenzenes are one of the safety solvents used in resist compositions that are sensitive to any of electron beams, X-rays, ultraviolet rays, and deep ultraviolet rays.
Therefore, being soluble in the alkoxybenzene, that is, having high solubility in the alkoxybenzene, means that the fullerene derivative of the present invention is dissolved in the solvent used in the industry as described above. Indicates that it is possible.

  In addition, when the fullerene derivative is dissolved in the alkoxybenzene, the fullerene derivative is likely to be soluble in other organic solvents as well. Accordingly, the high solubility of the fullerene derivative of the present invention in alkoxybenzene means that the fullerene derivative of the present invention can be used in organic solar cells such as dye-sensitized solar cells and organic thin film solar cells, organic transistors and diodes, organic electric fields. General organic devices such as light-emitting elements (organic EL elements), nonlinear optical materials, etc .; resin additives; lubricants; insulating films, base materials for lithium secondary batteries and fuel cells or capacitors, and additives and surface modifications thereof Coating materials, other materials and additives that constitute members such as separators; ceramic additives; additives for sliding applications such as solid lubricants and lubricating oil additives, catalysts, and paints, inks, pharmaceuticals, and cosmetics -It shows that it can be applied to various industrial fields such as diagnostics.

[2. Method for producing fullerene derivative]
There is no restriction | limiting in the method to manufacture the fullerene derivative of this invention, It can manufacture by arbitrary methods.

Conventionally, a general method for producing a fullerene derivative having a triple addition partial structure and / or a pentaaddition partial structure in which a hydrogen atom or a substituent is bonded to C ¹ has already been disclosed. Specifically, when C ¹ is bonded to an organic group, a method described in JP-A-2005-15470 or Chemistry Letters (2004, p. 328) can be used. Further, when a hydrogen atom is bonded to C ¹ , the method described in Nature (419, 2002, p. 702-705) can be used. Furthermore, if the halogen atom is bonded to C ^1, it is possible to use a method described in JP-A-2002-241389. The fullerene derivative of the present invention can also be produced by the method described in the above document. In this case, the conditions described in the above document can be used as various conditions such as the reaction temperature, the type of solvent, the mixing order of the reagents, and the reaction time. It is possible to adopt.

Among them, the fullerene derivative of the present invention is preferably produced by the production method exemplified below. However, the manufacturing method illustrated below is an example of the manufacturing method of the fullerene derivative of this invention, and the manufacturing method of the fullerene derivative of this invention is not limited to the following examples.
In general, the fullerene derivative of the present invention can be produced only by addition reaction to fullerene. The detailed manufacturing method is shown below.

(Addition reaction to fullerene)
In the production method of the present invention, a fullerene, a transition metal, a Grignard reagent (Grignard reagent), and a raw material into which R ¹⁰ can be introduced (hereinafter referred to as “R ¹⁰ introduction agent” as appropriate) are prepared and reacted. The fullerene derivative of the present invention is obtained. At this time, a reaction solvent is usually used, and the reaction is allowed to proceed in the reaction solvent.

[2-1. Fullerene]
As the fullerene, [1. Various fullerenes listed as specific examples of fullerenes in the “fullerene derivative” column can be used. In addition, any 1 type may be used for fullerene, and 2 or more types may be used together by arbitrary combinations and a ratio.

[2-2. Transition metal]
In the production method of the present invention, at least one transition metal is present in the reaction system. The type of transition metal is not limited, but is preferably a transition metal selected from metals belonging to Group 10 and Group 11 of the long-period periodic table, and among these, from the viewpoint of reactivity, it is Group 11 metal. Copper metal is particularly preferred.
In addition, as a transition metal to be present in the reaction system, only one kind may be used alone, or two or more kinds may be used in any combination and ratio.

In addition, as the transition metal, as long as the reaction proceeds, a single transition metal or a transition metal complex may be used, and a metal compound containing the transition metal (transition metal compound) May be used.
Examples of the transition metal, transition metal complex and metal compound include copper bromide dimethyl sulfide complex, copper bromide dibutyl sulfide complex, copper iodide dimethyl sulfide complex, copper iodide dibutyl sulfide complex, copper chloride dimethyl sulfide complex, Copper chloride dibutyl sulfide complex, copper cyanide, copper fluoride, copper chloride, copper bromide, copper iodide, organic copper-phosphine complex, silver fluoride, silver chloride, silver bromide, silver iodide, gold fluoride, Gold chloride, gold iodide, palladium chloride, palladium bromide, palladium iodide, nickel chloride, nickel bromide, nickel iodide, platinum chloride, platinum bromide, platinum iodide, nickel cyclooctadiene complex, palladium cyclooctadiene Complex, platinum cyclooctadiene complex, nickel-phosphine complex, palladium-phosphine complex, platinum-phosphine Body, and the like. Among these, copper bromide and copper bromide dimethyl sulfide complexes which are Group 11 metals and monovalent metal compounds and metal complexes are preferable from the viewpoint of reactivity. In addition, the transition metal simple substance, complex, and metal compound may be used alone or in combination of two or more in any combination and ratio.

  The content of the transition metal in the reaction system is arbitrary as long as the above reaction proceeds, but the ratio to the fullerene is usually 4 times mol or more, preferably 6 times mol or more, and usually 32 times mol or less, preferably Is preferably 16 times mole or less. If the transition metal content is too high, the production cost increases, and separation from the fullerene derivative may be difficult. If the transition metal content is too low, the reaction may not be completed. In addition, when using together 2 or more types of transition metals, it is desirable that those total amount satisfy | fills the said range. Furthermore, when using 2 or more types of the transition metal simple substance, complex, and metal compound, the total amount of the transition metal contained in the simple substance, complex, and metal compound of the transition metal used satisfies the above range. Is preferred.

[2-3. Grignard reagent]
In the production method of the present invention, at least one Grignard reagent is present in the reaction system. In accordance with the methods described in the above patent documents and non-patent documents, R ²⁰ (ie, —Ar—OR) of the fullerene skeleton can be added by allowing a Grignard reagent to coexist in the reaction system.

The supply timing of these Grignard reagents into the system is not limited as long as the desired fullerene derivative is obtained. However, in the production method of the present invention, it is desirable to carry out a reaction of adding R ²⁰ to C ^{6 to} C ⁸ or C ^{6 to} C ¹⁰ of the partial structure of formula (I) before introducing R ¹⁰ . For this reason, the Grignard reagent is usually introduced into the reaction system before the reaction in which the R ¹⁰ introduction agent is allowed to act.

The Grignard reagent is not limited as long as the effects of the present invention are not significantly impaired. For example, a compound represented by (Ar—OR) -MX ′ can be used.
Here, regarding the (Ar-OR) group, [1. It is the same as Ar-OR described in <About the organic group (R ²⁰ ) having a structure represented by the formula (II)> of the fullerene derivative], and may be selected according to the structure of the target fullerene derivative of the present invention. .
M represents a metal element. M is not limited as long as the effects of the present invention are not significantly impaired. Specific examples of M include magnesium, zinc, mercury, lithium and the like, among which magnesium is preferable.
Further, X ′ represents a halogen atom. Examples of X ′ include a chlorine atom, a bromine atom, and an iodine atom, among which a bromine atom and an iodine atom are preferable, and a bromine atom is particularly preferable.

When the above-mentioned Grignard reagent is used, the amount used is usually 4 times mol or more, preferably 6 times mol or more, and usually 32 times mol or less, preferably 16 times mol or less, in the ratio to the raw material fullerene. Is desirable. If the amount of the Grignard reagent used is too large, the production cost increases, and a large amount of R ¹⁰ introduction agent used for stopping the reaction may be required. If the amount is too small, the reaction may not be completed. In addition, only 1 type may be used for a Grignard reagent, and 2 or more types may be used together by arbitrary combinations and a ratio. When two or more kinds of Grignard reagents are used, it is desirable that the total amount thereof satisfies the above range.

[2-4. R ¹⁰ introducing agent]
As the R ¹⁰ introduction agent, an appropriate agent may be used depending on the group to be introduced (that is, R ¹⁰ ). For example, when producing a fullerene derivative in which R ¹⁰ is a hydrogen atom, the R ¹⁰ introducing agent is not limited as long as a hydrogen atom can be introduced into the fullerene skeleton.
Examples of the R ¹⁰ introduction agent include acidic aqueous solutions such as an aqueous ammonium chloride solution and an aqueous hydrogen chloride solution. In order to suppress the oxidation reaction, it is preferable to perform an oxidation reaction suppression operation such as deaeration so that oxygen is not mixed into the acidic aqueous solution.

For example, when producing a fullerene derivative in which R ¹⁰ is an organic group, the R ¹⁰ introduction agent is not particularly limited as long as the organic group can be introduced into the fullerene skeleton. As an example of the R ¹⁰ introduction agent, the compound R ¹⁰ -X ″ having a structure in which the organic group R ¹⁰ and the leaving group X ″ are bonded to each other can be used.
In this case, the leaving group X ″ is not particularly limited as long as it can be a leaving group in a nucleophilic substitution reaction. For example, a halogen atom such as a chlorine atom, a bromine atom or an iodine atom; an acetoxy group An acyloxy group such as a trifluoroacetoxy group; a sulfonyloxy group such as a methanesulfonyloxy group and a benzenesulfonyloxy group; etc. Among these, from the viewpoint of reactivity and raw material procurement, the leaving group X ″ is a halogen atom. Are preferable, and a bromine atom and an iodine atom are particularly preferable.

Furthermore, for example, when producing a fullerene derivative in which R ¹⁰ is a halogen atom, the R ¹⁰ introduction agent is not limited as long as the halogen atom can be introduced into the fullerene skeleton.
Examples of the R ¹⁰ introduction agent include halogenating agents such as chlorine, bromine, iodine, N-bromosuccinimide, N-chlorosuccinimide, and N-iodosuccinimide. Among these, N-bromosuccinimide is preferable from the viewpoint of reactivity.

In the case of producing a fullerene derivative in which R ¹⁰ is an organic group, and in the case of producing a fullerene derivative in which R ¹⁰ is a halogen atom, for example, an R ¹⁰ introduction agent in a system in which a transition metal is present. Alternatively, a method for producing in situ may be used. In such a case, a method may be used in which a hydrogen atom is first introduced into C ¹ of the fullerene skeleton, followed by treatment with an appropriate base, and then desired R ¹⁰ is introduced with the R ¹⁰ introduction agent. At this time, an appropriate method may be selected depending on R ^{10 to} be introduced. When using a base, the kind described in JP-A-2005-15470 can be referred to.

Any one of R ¹⁰ introduction agents may be used, or two or more thereof may be used in any combination and ratio. However, in order to obtain a single compound, it is preferable to use only one of them alone. Among them, with respect to the R ¹⁰ introduction agent, methyl iodide is used from the viewpoint of ease of reaction, product stability and cost reduction, and allyl bromide, allyl iodide, crotyl bromide, crotyl from the viewpoint of improving solubility. It is preferable to use each of iodide, cinnamyl bromide, and cinnamyl iodide alone.

The amount of the R ¹⁰ introduction agent used is usually 1 times mol or more, preferably 5 times mol or more, and usually 100 times mol or less, preferably 50 times mol or less with respect to fullerene. If the amount of the R ¹⁰ introduction agent is too large, it may be disadvantageous in terms of production cost. If the amount of the R ¹⁰ introduction agent is too small, it reacts with the Grignard reagent remaining in the reaction system, and the reaction is in progress. The target compound (fullerene derivative of the present invention) may not be obtained. Note that when used in combination R ¹⁰ introducing agent of two or more, it is desirable that the total amount of them to satisfy the above range.

[2-5. Reaction solvent]
In the production method of the present invention, at least the above-mentioned fullerene, transition metal, Grignard reagent and R ¹⁰ introduction agent may be used, but a reaction solvent may be further used.
When a reaction solvent is used, the type thereof is arbitrary as long as it can dissolve and / or disperse the above-mentioned fullerene, transition metal, Grignard reagent and R ¹⁰ introduction agent suitably.

  Specific examples of the reaction solvent include halogen-substituted aromatic solvents such as orthodichlorobenzene (ODCB), chlorobenzene and trichlorobenzene; aromatic solvents such as benzene, toluene, xylene and trimethylbenzene; halogen hydrocarbons such as chloroform and dichloromethane Solvents; ether solvents such as diethyl ether, dibutyl ether, tetrahydrofuran (THF), 1,4-dioxane, methylcyclopentyl ether; pyridine solvents such as pyridine, methylpyridine, dimethylpyridine and the like. A reaction solvent may be used individually by 1 type, and may be used 2 or more types by arbitrary ratios and combinations.

  The reaction solvent is preferably used in combination with a halogen-substituted aromatic solvent capable of suitably dissolving fullerene and an ether solvent capable of stably dissolving the Grignard reagent. Specifically, ODCB and THF are used. It is preferable to use in combination.

When a reaction solvent is used, the amount used is usually 1 mg / mL or more, preferably 5 mg / mL or more, and usually 40 mg / mL or less, preferably 20 mg / mL or less, as a ratio to fullerene. If the amount of the reaction solvent used is too large, the concentration of the raw material becomes thin and the reaction rate may be slow. If the amount is too small, the raw material and the product cannot be dissolved, and the reaction may not proceed completely.
In addition, when using together 2 or more types of reaction solvent, it is desirable to make those total amount satisfy | fill the said range.

[2-6. Operation and reaction conditions]
The order and reaction conditions for mixing the above-mentioned fullerene, transition metal, Grignard reagent and R ¹⁰ introduction agent, and a reaction solvent used as necessary are arbitrary as long as the fullerene derivative of the present invention can be produced. Further, the reaction system may contain components other than those described above as long as the progress of the reaction is not inhibited.

However, usually, after the transition metal simple substance, complex and / or metal compound is suspended in the reaction solvent, after blending the Grignard reagent, the fullerene is blended, and then the R ¹⁰ introducing agent is blended. preferable. According to this procedure, it is considered that the fullerene derivative to which R ²⁰ (that is, —Ar—OR) is added and the transition metal form an intermediate having a complex structure at the stage of adding the R ¹⁰ introduction agent. Therefore, it is effective to add an R ¹⁰ introduction agent at that stage.

Regarding the intermediate formed by the C ₆₀ derivative and / or C ₇₀ derivative and the copper metal, the "Quarterly chemical review 43 carbon third allotrope fullerene chemistry" 169-170 page, the estimated structure described Has been.

The temperature conditions during the reaction are not limited as long as the reaction proceeds, but in general, the temperature of the reaction system after adding the R ¹⁰ introducing agent to the reaction system is usually 0 ° C. or higher, preferably 15 ° C. or higher, Usually, it is desirable that the temperature is 100 ° C. or lower, preferably 70 ° C. or lower.
Although the reaction time is not limited, generally, after adding the R ¹⁰ introducing agent to the reaction system, it is usually 30 minutes or longer, preferably 2 hours or longer, and usually several tens of hours or shorter, preferably 10 hours or shorter. It is desirable to react.

The R ¹⁰ introduction agent is usually added to the reaction system when the fullerene conversion rate exceeds a predetermined value, but in order to prevent oxidation of the product, degassing such as nitrogen bubbling or vacuum deaeration is performed. It is preferable to add to the reaction system after performing a gas operation. Here, the predetermined numerical value means that the conversion of fullerene is usually 75% or more, preferably 90% or more, more preferably 95% or more, and the upper limit is usually 100% or less, preferably 99. It represents a state of 5% or less, more preferably 99.0% or less. In addition, the method currently reported by said patent document, nonpatent literature, etc. can be employ | adopted so far about other operation regarding manufacture.

  After completion of the reaction, the produced fullerene derivative of the present invention is usually isolated from the reaction solution by a conventional method. The isolation operation varies depending on the type of each reaction.For example, after filtering the reaction solution to remove the metal component, the solution is crystallized with a poor solvent such as methanol, or extracted with an appropriate solvent and then separated. The product can be isolated by distilling off the solvent.

  The obtained fullerene derivative of the present invention may be purified by a technique such as high performance liquid chromatography (HPLC), silica gel column chromatography, alumina column chromatography, recrystallization or the like as necessary. The isolation yield is usually 70% or more, preferably 80% or more, particularly preferably 90% or more, as the yield from the fullerene derivative intermediate, when carried out under the above-mentioned preferable reaction conditions.

The fullerene derivative of the present invention is usually a proton nuclear magnetic resonance spectrum method (hereinafter sometimes referred to as “ ¹ H-NMR” as appropriate) or a carbon nuclear magnetic resonance spectrum method (hereinafter referred to as “ ¹³ C-NMR” as appropriate). ), Infrared absorption spectroscopy (hereinafter sometimes referred to as “IR” as appropriate), mass spectrometry (hereinafter also referred to as “MS” as appropriate), and general organic analysis such as elemental analysis, Its structure can be confirmed. In addition, when the crystallinity of the fullerene derivative is good, the structure may be confirmed by an X-ray crystal diffraction method.

[3. Fullerene derivative solution]
The fullerene derivative of the present invention can be used for various applications described above by dissolving in a suitable solvent to form a solution. Hereinafter, the fullerene derivative solution of the present invention in which the fullerene derivative of the present invention is dissolved in a solvent is referred to as “the solution of the present invention” as appropriate.

  Although the kind of the solvent in the solution of the present invention is arbitrary, a preferred example includes an organic solvent. As the organic solvent, any organic solvent known so far can be used. Among them, since the fullerene derivative of the present invention has an ether group and an aromatic ring, it exhibits high solubility in an ether solvent, particularly alkoxybenzene. Therefore, these organic solvents should be used as the solvent of the solution of the present invention. Is preferred.

The type of organic solvent is not limited, but examples include alcohols such as methanol, ethanol, and isopropanol; ketones such as acetone, methyl ethyl ketone, methyl isoamyl ketone, methyl amyl ketone, and cyclohexanone; methyl acetate, ethyl acetate, propyl acetate, Esters (ester solvents) such as butyl acetate, methyl propionate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, and γ-butyrolactone; tetrahydrofuran, dioxane, anisole, 1,2-dimethoxy Benzene, 1,3-dimethoxybenzene, ethyl phenyl ether, propyl phenyl ether, n-butyl phenyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc. Ethers; ether alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol; acids such as the ether alcohols and acetic acid Ether esters (ester solvents) that are ester compounds with amides; amides such as N, N-dimethylformamide and N-methylpyrrolidone; nitriles such as acetonitrile and benzonitrile; polar organic solvents such as dimethyl sulfoxide and the like .
Among these, ethers are preferably used from the viewpoint of solubility, ethers having an aromatic ring are particularly preferable, and anisole is particularly preferably used from the viewpoint of boiling point.

  In the solution of the present invention, only one solvent may be used, or two or more solvents may be used in any combination and ratio. Therefore, as for the said organic solvent, all may use only 1 type and may use 2 or more types together by arbitrary combinations and ratios.

  Furthermore, the ratio of the fullerene derivative of the present invention to the solvent in the solution of the present invention is arbitrary. Moreover, in the solution of the present invention, the fullerene derivative of the present invention is preferably completely dissolved in a solvent, but may be partially suspended without being dissolved or may be precipitated.

  As long as the excellent physical properties of the fullerene derivative of the present invention are not significantly impaired, the solution of the present invention may contain other components in addition to the fullerene derivative and the solvent of the present invention. Other components may contain only 1 type and may contain 2 or more types by arbitrary combinations and ratios.

  As long as the fullerene derivative of the present invention can be dissolved in a solvent, the method for preparing the solution of the present invention is not limited, but it can usually be prepared by a method of dissolving with stirring in a predetermined apparatus, a method of irradiating ultrasonic waves, or the like. . Further, the mixing order of the fullerene derivative of the present invention, the solvent, and other components used as necessary is not particularly limited.

  The solution of the present invention is usually prepared at about 25 ° C. from the viewpoint of stability and operability, but can be dissolved and stored while heating as long as it is below the boiling point of the solvent. Moreover, although the fullerene derivative of this invention may precipitate, unless all the fullerene derivatives of this invention contained in a solution precipitate, it can also prepare and store at 25 degrees C or less low temperature.

[4. Fullerene derivative film]
The fullerene derivative film of the present invention contains the fullerene derivative of the present invention. Since the fullerene derivative of the present invention exhibits high solubility in the above-described organic solvents, particularly ether solvents, it is possible to produce a fullerene derivative film by applying the fullerene derivative solution to an arbitrary substrate and drying by heating. it can. The fullerene derivative solution used in this case may contain other arbitrary compounds in addition to the fullerene derivative and the organic solvent as long as the excellent physical properties of the fullerene derivative of the present invention are not significantly impaired.

  As a coating method, for example, an arbitrary method such as a spray method, a spin coating method, a dip coating method, or a roll coating method can be used. There are no limitations on the base material to be applied, and examples thereof include organic films, silicon substrates, silicon films such as polysilicon films, silicon oxide films, and silicon nitride films, and inorganic films such as metal wiring.

  The heat drying treatment of the coating film is usually preferably performed at 80 to 300 ° C. for 10 to 300 seconds. Since the fullerene derivative of the present invention is excellent in thermal stability as compared with a normal organic compound, a stable film can be formed without thermal decomposition. Moreover, it is preferable to perform heating in air | atmosphere or inert gas atmosphere, such as argon and nitrogen.

  The film thickness in the fullerene derivative film of the present invention varies greatly depending on applications and cannot be uniformly limited, but is usually 10 nm or more, preferably 30 nm or more, and usually 1,000 nm or less, preferably 500 nm or less, more preferably Is 300 nm or less.

  The fullerene derivative film of the present invention can form a uniform film, and its refractive index and extinction coefficient can be measured with a spectroscopic ellipsometer or the like. Moreover, the dielectric constant and reflectance of the fullerene derivative film of the present invention can be calculated using these measured values. These optical constants vary greatly depending on the use of the fullerene derivative film, and also in the same use, depending on the type of process and the type and amount of other components contained in the fullerene derivative film. Therefore, it is preferable to use for the use which can utilize effectively the outstanding physical property which the fullerene derivative film | membrane of this invention has. In particular, the fullerene derivative film of the present invention has a fullerene derivative as a component thereof holding a large amount of π-electron conjugation of the fullerene skeleton, and an aromatic hydrocarbon group is introduced as a substituent. Therefore, since high etching resistance can be expected, it is suitably used for photoresist applications and lower layer films.

[5. Use of fullerene derivative, fullerene derivative solution, and fullerene derivative film]
The fullerene derivative of the present invention, the solution of the present invention, and the fullerene derivative film can be used for the aforementioned applications. Hereinafter, some examples of applications will be specifically described. However, the applications in which the function of the fullerene derivative of the present invention can be exhibited are not limited to the following descriptions.

[5-1. Photoresist application]
Conventionally, a photoresist is a composition in which a resin component such as a (meth) acrylic, polyhydroxystyrene or novolac resin as a film forming component is combined with an acid generator or a photosensitizer that generates an acid upon exposure. Widely used. Since the fullerene derivative of the present invention is usually highly soluble in an organic solvent used in a photoresist, it can be combined with the photoresist at a higher concentration without using a special solvent. Further, it is possible to form a resist film with a fullerene derivative alone.

  As described above, when the fullerene derivative of the present invention or the solution of the present invention is used in the field of photoresist, by having a fullerene skeleton, it has high heat resistance as a superaromatic molecule, high etching resistance, and edge roughness. It can be reduced and a high-resolution photoresist can be reproduced. In addition, the resist film formed by using the fullerene derivative of the present invention or the solution of the present invention also has a function as an antireflection film as apparent from the absorption spectrum, and thus exhibits an excellent function as a multilayer film. Is expected to do.

[5-2. Semiconductor manufacturing applications]
In the field of semiconductor manufacturing and the like, a nanoimprint method has been studied as a method for forming a fine pattern of 500 μm or less with high production efficiency. The nanoimprint method is a method for forming a fine pattern in which a pattern of a mold having a fine pattern is transferred to a transfer layer.

Examples of such a nanoimprint method include a step of heating and softening a transfer layer made of a thermoplastic polymer, a step of pressing the transfer layer and a mold to form a pattern of the mold on the transfer layer, and a mold. A step of sequentially removing the transfer layer; a step of contacting the transfer layer made of a curable monomer with the mold; a step of curing the curable monomer; and a mold from a cured product of the curable monomer. And a method of sequentially performing the step of releasing the
The fullerene derivative of the present invention is usually filled in the thermoplastic polymer at a high concentration without using a special solvent because of its high solubility in the organic solvent used for the thermoplastic polymer and curable material. Is possible.

  As described above, when the fullerene derivative of the present invention or the solution of the present invention is used in the nanoimprint method, the solubility of the fullerene derivative of the present invention in an organic solvent is high, so the fullerene derivative of the present invention in the thermoplastic polymer. Aggregation is suppressed, resulting in molecular dispersion. For this reason, it is possible to realize high resolution. Furthermore, by using the fullerene derivative of the present invention or the solution of the present invention for the nanoimprint method, it is possible to improve the mechanical strength, heat resistance and etching resistance of the transfer layer. Significant improvement is possible.

[5-3. Low dielectric constant insulation materials]
In recent years, resin thin film wiring suitable for high-density and fine multilayer wiring using a resin thin film as an interlayer insulating film has been applied to a circuit board for a central processing unit (CPU) of a computer. In order to realize a computer having a higher processing speed in the future, development of a low dielectric constant insulating material that utilizes high-density and delicate multilayer wiring and is suitable for high-speed signal propagation is required. The fullerene derivative of the present invention can be complexed with other materials at a higher concentration without using a special solvent because the fullerene derivative of the present invention usually has high solubility in an organic solvent used for the above-mentioned applications. It is also possible to form a film with a fullerene derivative alone. At this time, the fullerene derivative of the present invention retains the properties of high resistance and low dielectric constant inherently possessed by the fullerene structure, and has an effect of improving mechanical strength as a filler when used in combination. As a result, it is possible to realize an interlayer insulating film having a low dielectric constant with an excellent performance which has not been achieved conventionally.

[5-4. Solar cell application]
Application to organic solar cells is also possible. In this field, the organic solar cell has many advantages as compared with the silicon-based inorganic solar cell, but has low energy conversion efficiency and does not sufficiently reach a practical level. In order to overcome this problem, a bulk heterojunction type organic solar cell having an active layer in which a conductive polymer as an electron donor and fullerenes and fullerene derivatives as electron acceptors are mixed has been proposed recently. . In this bulk heterojunction type organic solar cell, the conductive polymer and the fullerene derivative are mixed at the molecular level, and as a result, a very large interface is successfully created, and the conversion efficiency is greatly improved.

  Since the fullerene derivative of the present invention has high solubility in an organic solvent used in the above-mentioned applications, it is easy to form an efficient bulk heterojunction structure with a p-type semiconductor. The fullerene derivative of the present invention essentially retains the properties of fullerene as an n-type semiconductor. For these reasons, if the fullerene derivative of the present invention or the solution of the present invention is used, an extremely high performance organic solar cell can be realized. Furthermore, by utilizing this high solubility, it is possible to control layer separation from electron donor layers such as conductive polymers, and to control morphology such as alignment orientation and fine packing of derivative molecules, thereby improving characteristics. In addition, it provides great flexibility in device design. Also, in terms of production, it is possible to easily realize a large area at low cost by ordinary printing methods, ink jet printing, and spraying.

[5-5. Semiconductor application]
Research has been made on the use of fullerenes and fullerene derivatives as organic materials for field-effect transistors that can be expected to be applied to optical sensors, rectifiers, and the like. In general, when a field effect transistor is manufactured using fullerene and a fullerene derivative as a semiconductor, it is known that the field effect transistor functions as an n-type transistor. The fullerene derivative of the present invention has a high solubility in an organic solvent used in the above-mentioned applications, and therefore, film formation by coating is easy, and the essential properties of fullerene as an n-type semiconductor are retained. . Thereby, the fullerene derivative of the present invention can be expected as a low-cost, high-performance organic semiconductor.

  EXAMPLES Hereinafter, the present invention will be further described with reference to examples. However, the present invention is not limited to the following examples, and can be arbitrarily modified without departing from the gist of the present invention. . In the description of the present specification, THF represents tetrahydrofuran, and ODCB represents orthodichlorobenzene. Further, Me represents a methyl group, Np represents a naphthyl group, and Ph represents a phenyl group.

Example _{1: C 60 (-β-C} 10 H 6 -6-OCH 3) 5 preparation of (-CH _3)]
(Synthesis)
A THF suspension (84 mL) of a copper (I) dimethyl sulfide complex (9.72 g, 47.3 mmol) was cooled to 5 ° C., and then the Grignard reagent 6-synthesized from 2-bromo-6-methoxynaphthalene was used. OCH ₃ —C ₁₀ H ₆ MgBr / THF solution (1 mol / L; 51 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 mL, 48 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 / ethyl acetate = 1/1 (v / v)). The solution was concentrated, crystallized with methanol (500 mL), and vacuum-dried at 180 ° C., whereby C ₆₀ {β- (6-OCH ₃ —C ₁₀ H ₆ )} ₅ (—CH ₃ ) orange A colored solid (6.10 g, 4.01 mmol) was obtained as the product (96.2% yield).

(analysis)
The obtained product was measured by HPLC and ¹ H-NMR to identify the product. The solubility of the product was also measured.

・ HPLC
For HPLC, a 0.5 mg / mL toluene solution was prepared and measured under the following measurement conditions.

Column type: ODS
Column size: 150mm x 4.6mmφ
Eluent: Toluene / methanol = 3/7
Detector: UV290nm

  As a result of HPLC measurement, it was observed at 97.7 (Area%) at a retention time of 16.30 minutes.

・¹ H-NMR
¹ H-NMR was measured under conditions of 400 MHz using CDCl ₃ as a solvent.

The measurement result of ¹ H-NMR was as follows.

From the above results, it obtained product is _{C 60 (-β-C 10 H} 6 -6-OCH 3) 5 (-CH 3) was confirmed.

-Solubility measurement Furthermore, the obtained product was dissolved in anisole at 25 ° C under normal pressure, and the solubility was measured. The results are shown in Table 1 below.

Example _{2: C 60 (-C 6 H} 3 -3-CH 3 -4-OCH 3) 5 preparation of (-CH _3)]
(Synthesis)
A THF suspension (112 mL) of copper (I) dimethyl sulfide complex (12.96 g, 63.1 mmol) was cooled to 5 ° C., and then the Grignard reagent synthesized from 5-bromo-2-methoxytoluene 4- OCH ₃ -3-CH ₃ —C ₆ H ₃ MgBr / THF solution (1 mol / L; 68 mL) was added, and the temperature was raised to 25 ° C.
An ODCB solution (180 mL) of C ₆₀ (4.0 g, 5.56 mmol) was added thereto and stirred for 5 hours.
To this, MeI (4 mL, 64 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). The solution was concentrated, crystallized with methanol (800 mL), and vacuum-dried at 180 ° C., whereby C ₆₀ (—C ₆ H ₃ -3-CH ₃ -4-OCH ₃ ) ₅ (—CH ₃ ) Of an orange solid (6.55 g, 4.89 mmol) as product (yield 88.0%).

(analysis)
In the same manner as in Example 1, the obtained product was measured by HPLC and ¹ H-NMR to identify the product. The solubility of the product was also measured.

・ HPLC
As a result of HPLC measurement, it was observed at 96.7 (Area%) at a retention time of 14.65 minutes.

・¹ H-NMR
The measurement result of ¹ H-NMR was as follows.

From the above results, it obtained product is _{C 60 (-C 6 H 3 -3} -CH 3 -4-OCH 3) 5 (-CH 3) was confirmed.

-Solubility measurement Furthermore, about the obtained product, it carried out similarly to Example 1, and measured the solubility. The results are shown in Table 1 above.

[Example 3: Production of C ₆₀ (—C ₆ H ₂ -3,5- (CH ₃ ) ₂ -4-OCH ₃ ) ₅ (—CH ₃ )]
(Synthesis)
A Grignard reagent synthesized from 3,5-dimethyl-4-methoxybromobenzene after cooling a THF suspension (168 mL) of copper (I) bromide dimethyl sulfide complex (19.44 g, 94.7 mmol) to 5 ° C. 4-OCH ₃ -3,5- (CH ₃ ) ₂ —C ₆ H ₂ MgBr / THF solution (1 mol / L; 102 mL) was added, and the temperature was raised to 25 ° C.
An ODCB solution (270 mL) of C ₆₀ (6.0 g, 8.34 mmol) was added thereto and stirred for 4 hours.
To this, MeI (6 mL, 96 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 / ethyl acetate = 1/1 (v / v)). The solution was concentrated, crystallized with methanol (900 mL), and vacuum-dried at 180 ° C., whereby C ₆₀ (—C ₆ H ₂ -3,5- (CH ₃ ) ₂ -4-OCH ₃ ) ₅ An orange solid (10.59 g, 7.51 mmol) of (—CH ₃ ) was obtained as the product (yield 90.1%).

(analysis)
In the same manner as in Example 1, the obtained product was measured by HPLC and ¹ H-NMR to identify the product. The solubility of the product was also measured.

・ HPLC
As a result of HPLC measurement, it was observed at 95.2 (Area%) at a retention time of 15.37 minutes.

・¹ H-NMR
The measurement result of ¹ H-NMR was as follows.

From the above results, it obtained product is _{C 60 (-C 6 H 2 -3,5-} (CH 3) 2 -4-OCH 3) 5 (-CH 3) was confirmed.

-Solubility measurement Furthermore, about the obtained product, it carried out similarly to Example 1, and measured the solubility. The results are shown in Table 1 above.

Comparative Example _{1: C 60 (-C 6 H} 4 -4-OCH 3) 5 preparation of (-CH _3)]
(Synthesis)
A THF suspension (84 mL) of copper (I) dimethyl sulfide complex (9.72 g, 47.4 mmol) was cooled to 5 ° C., and then 4-OCH ₃ − of Grignard reagent synthesized from 4-methoxybromobenzene. C ₆ H ₄ MgBr / THF solution (1 mol / L; 51 mL) was added, and the temperature was raised to 25 ° C.
An ODCB solution (135 mL) of C ₆₀ (2.0 g, 2.78 mmol) was added thereto and stirred for 10 hours.
To this, MeI (4 mL, 64 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 / ethyl acetate = 1/1 (v / v)). The solution was concentrated, crystallized with methanol (300 mL), and vacuum-dried at 50 ° C., whereby an orange solid of C ₆₀ (—C ₆ H ₄ -4-OCH ₃ ) ₅ (—CH ₃ ) ( 3.49 g, 2.75 mmol) were obtained as the product (98.9% yield).

(analysis)
In the same manner as in Example 1, the obtained product was measured by HPLC and ¹ H-NMR to identify the product. The solubility of the product was also measured.

・ HPLC
As a result of HPLC measurement, it was observed at 97.4 (Area%) at a retention time of 10.98 minutes.

・¹ H-NMR
The measurement result of ¹ H-NMR was as follows.

From the above results, it was confirmed that the obtained product was C ₆₀ (—C ₆ H ₄ -4-OCH ₃ ) ₅ (—CH ₃ ).

-Solubility measurement Furthermore, about the obtained product, it carried out similarly to Example 1, and measured the solubility. The results are shown in Table 1 above.

[Example 5]
Using the product obtained in Example 1, resist evaluation was performed by the method described below.
(1) Preparation of resist composition (i) ZEP520A (manufactured by Nippon Zeon, anisole solvent) as a resist was diluted twice with anisole as a non-halogen aromatic solvent.
(Ii) Compound 1 as a fullerene derivative was added to 1 wt% with respect to ZEP520A before dilution, and the mixture was stirred overnight with a stirrer.
(Iii) After stirring, the mixture was filtered with a filter having a pore diameter of 0.1 μm to obtain a resist composition.

(2) Formation of resist film The resist composition prepared above was spin-coated on a Si substrate to a thickness of 100 nm (coating process), and heat-treated at 170 ° C. for 20 minutes (heating process). .

(3) Exposure Using an EB exposure apparatus: JBX-6000FS (manufactured by JEOL Ltd.), exposure was performed at an acceleration voltage of 50 kV.

(4) Development / Rinse ZED-N50 (manufactured by Nippon Zeon Co., Ltd.) was used as a developer, and immersed in this for 45 seconds (development process). Thereafter, IPA (isopropyl alcohol) was used as a rinsing solution, and the developer was rinsed off by immersing in IPA (30 seconds).

(5) Evaluation (5) -1: Sensitivity evaluation The remaining film ratio with respect to the exposure time (percentage of the film thickness after development with respect to the initial film thickness before development) was measured with a film thickness meter (alpha step 500 manufactured by KLA Tencor). A sensitivity curve was obtained. The results are shown in FIG. In FIG. 1, a solid line is Example 5 and a broken line is Comparative Example 2 described later.

(5) -2: Evaluation of resolving power A line & spa pattern having a line width of 30 nm to 200 nm was formed, and cross-sectional observation was performed using SEM (Hitachi S-5200). FIG. 2 shows a drawing-substituting photograph showing an electron micrograph of a pattern cross-sectional shape of a line & space pattern having line widths of 50 nm, 70 nm, and 100 nm at an exposure amount of 120 μC.

(5) -3: Evaluation of etching resistance (i) After pattern formation, the step between the pattern and the Si substrate was measured. The measured level difference was defined as film thickness A (resist film thickness).
(Ii) A sample was prepared for each required time and etched according to the following procedure.
(RIE etching with CF ₄ gas)
Equipment: RIE-10NR manufactured by Samco International
Etching conditions: CF ₄ , 50 W, 70 sccm, 20 Pa
Etching time: 0 seconds, 60 seconds, 120 seconds, 180 seconds, 240 seconds, 300 seconds Film loss measurement: Alpha step 500 manufactured by KLA Tencor
(Iii) The level difference between the pattern and the Si substrate was measured. The measured step size was defined as film thickness B.
(Iv) The level difference between the Si substrate patterned after ashing and the Si base of the non-patterned portion was measured. The measured step size was defined as film thickness C.
The ashing was performed as follows.
(Resist stripping by O ₂ ashing)
Equipment: RIE-10NR manufactured by Samco International
Ashing conditions: O ₂ = 20 sccm, 50 W, 20 Pa, 5 minutes Measurement of film loss: Alpha step 500 manufactured by KLA Tencor

(V) The amount of film reduction of the resist film and the Si substrate was determined by the following calculation formula.
Reduction amount of resist film = film thickness A + film thickness C−film thickness B
Reduction amount of Si substrate film = film thickness C
(Vi) The etching rate of the resist film and the Si substrate was calculated from the slope of the graph of the etching time and the amount of film reduction.
(Vii) Normalization was performed by dividing the etching rate of the resist film by the etching rate of the Si substrate.
(Viii) The etching rate of the resist film to which the standardized fullerene derivative is not added (Comparative Example 2 to be described later) is divided by the etching rate of the resist film to which the standardized fullerene derivative is added (Example 5). The ratio of the obtained speed was calculated as an improvement rate ([%]) and compared.
The results are shown in Table 2.

(5) -4: LER (Line Edge Roughness) Evaluation A line & space pattern having a line width of 70 nm was formed, and the surface was observed by SEM (Hitachi S-5200) and indicated by 3σ values of each edge value distribution of Line 400 points. The edge detection method was the threshold method. Measurement was carried out at 14 locations by this method, and the average value was taken as the LER value of each sample.
The results are shown in Table 3.

[Comparative Example 2]
Resist evaluation similar to that in Example 1 was performed without adding the fullerene derivative. Each evaluation result is shown in FIG. 1, FIG. 2, Table 2, and Table 3, respectively.

[Results: Example 5, Comparative Example 2]
<Sensitivity evaluation>
From the above results, it was found that the addition of the fullerene derivative slightly lowered the sensitivity, but the film reduction phenomenon in the low exposure region was suppressed, and the addition of the fullerene derivative improved the pattern contrast.

<Resolution evaluation>
The resolution and sensitivity were not lowered by the addition of the fullerene derivative, and the resolution was up to 50 nm. Moreover, compared with the comparative example 2 which is an additive-free product, in Example 5, the rectangularity of the pattern top was improved, and it was found from this evaluation that the pattern contrast was also improved.

<Etching resistance evaluation>
Compared to Comparative Example 2 in which ZEP520A was not added with a fullerene derivative, Example 5 showed an effect of improving etching resistance by 7% by adding a fullerene derivative.

<LER evaluation>
Compared to Example 2 in which no fullerene derivative was added, Example 5 has improved LER.

  The fullerene derivative of the present invention can be used in any field. Among them, the fullerene derivative of the present invention is characterized by having a high solubility in a polar organic solvent and can be easily produced at low cost. For example, production of optical disc materials such as DVD and CD. It can be preferably used for applications such as production of a semiconductor integrated circuit, production of a mask for producing a semiconductor integrated circuit, production of an integrated circuit for liquid crystal, a resist material for producing a liquid crystal screen. In addition to KrF excimer lasers and ArF excimer lasers, it can be used as an underlayer film material that functions as a photoresist and antireflection film suitable for shortening the wavelength of light sources such as EUV (extreme ultraviolet light) and EB (electron beam). It can be particularly preferably used for applications of photoresist, nanoimprint, and interlayer insulating film.

It is a graph showing the result of the sensitivity evaluation of the Example and comparative example of this invention. The solid line is Example 5 and the broken line is Comparative Example 2. It is a drawing substitute photograph showing the result of the resolution evaluation of the Example and comparative example of this invention.

Claims (13)

In a partial structure represented by the following formula (I) of the fullerene skeleton having a solubility in anisole at an atmospheric pressure of 25 ° C. of 10% by weight or more, C ¹ is bonded to a hydrogen atom or an arbitrary substituent. A fullerene derivative, wherein at least C ^{6 to} C ⁸ are each independently bonded to an organic group having a structure represented by the following formula (II).
(In the formula (I), C ^{1 to} C ¹⁰ all represent carbon atoms constituting the fullerene skeleton.)
(In the formula (II), Ar represents an aromatic hydrocarbon group having 6 to 18 carbon atoms, and R represents an alkyl group or an aryl group which may have a substituent.) The fullerene derivative according to claim 1, wherein Ar in the formula (II) is a hydrocarbon group having a naphthalene skeleton. The fullerene derivative according to claim 1, wherein the organic group having a structure represented by the formula (II) is represented by the following formula (III).
(In the formula (III), X represents an organic group or a halogen atom before the third period, and m represents an integer of 1 or more and 4 or less, provided that when m is 2 or more, X is the same type. Or different types.) R in said formula (II) is a C1-C6 alkyl group, The fullerene derivative as described in any one of Claims 1-3 characterized by the above-mentioned. The fullerene derivative according to claim 4, wherein R in the formula (II) is a methyl group. C ^{6 to} C ¹⁰ in the formula (I) are each independently bonded to an organic group having a structure represented by the formula (II). The fullerene derivative according to item. The fullerene derivative according to any one of claims 1 to 6, wherein C ¹ in the formula (I) is bonded to an organic group having 1 to 30 carbon atoms. The fullerene derivative according to claim 1, wherein C ¹ in the formula (I) is bonded to a methyl group. The fullerene derivative according to claim 1, wherein C ¹ in the formula (I) is bonded to an alkenyl group. The fullerene skeleton, characterized in that it is a fullerene C _60, fullerene derivative according to any one of claims 1 to 9. A fullerene derivative solution, wherein the fullerene derivative according to any one of claims 1 to 10 is dissolved in a solvent. The fullerene derivative solution according to claim 11, wherein the solvent is alkoxybenzene. A fullerene derivative film comprising the fullerene derivative according to any one of claims 1 to 10.