JP5308379B2 - π-electron conjugated polymer composition and electrochromic display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent composition that is suitable for use in opposite electrodes of electrochromic display devices and includes &pi;-electron conjugated polymers and carbon nanotubes. <P>SOLUTION: The composition includes a &pi;-electron conjugated polymer the constitutional unit of which is a compound expressed by formula (1) and carbon nanotubes [wherein X is at least one selected from the group consisting of an oxygen atom, sulfur atom, -NH-, and -NR<SP>1</SP>- (R<SP>1</SP>is a 1-10C alkyl group optionally having a substituent); Y is an oxygen atom or a sulfur atom; and Z's are each independently at least one selected from the group consisting of a hydrogen atom and a 1-20C organic group optionally having a substituent]. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a transparent composition suitable for an electrode, particularly for a counter electrode, including a π-electron conjugated polymer and a carbon nanotube, a method for producing the same, and an electrochromic display element obtained using the composition.

  In recent years, as an electronic medium replacing paper, it is expected to realize electronic paper that combines the advantages of paper and the advantages of a display that can handle digital information as it is. The characteristics required for electronic paper include a reflective display element, high white reflectance and high contrast ratio, high-definition display, memory effect on display, and driving at low voltage. It can be done, it is thin and light, and it is inexpensive.

  As a display method of electronic paper, there are a reflective liquid crystal method, an electrophoresis method, a two-color ball method, an electrochromic (hereinafter, abbreviated as EC) method, and the like. The reflective liquid crystal system includes a GH liquid crystal system using a dichroic dye, a cholesteric liquid crystal system, and the like. This reflection type liquid crystal method has an advantage of power saving because it does not use a backlight, compared to the conventional transmission type liquid crystal method. However, there is a problem that the screen is inevitably darkened because of viewing angle dependency and low light reflection efficiency. In addition, although the electrophoresis method and the two-color ball method have the advantages of low power consumption and no viewing angle dependency, it is difficult to obtain a high contrast, and a color filter is used for full color conversion. It is necessary to apply the side-by-side mixing method, which has a problem that the reflectance is lowered and the screen is inevitably darkened.

  On the other hand, the EC method uses reversible oxidation-reduction reaction by applying a voltage, and utilizes color development / decoloration that occurs in association therewith. EC display elements have already been used in automobile light control mirrors, watches and the like. The display using this EC display element does not require a polarizing plate, has no viewing angle dependency, has a light receiving type, has excellent visibility, has a simple structure, can be easily enlarged, and varies depending on the selection of materials. It has an advantage that light emission of a proper color tone is possible.

  In order to perform full color display on an EC display element, cyan (hereinafter sometimes abbreviated as C), magenta (hereinafter sometimes abbreviated as M), yellow (hereinafter abbreviated as Y) used for subtractive color mixing. There is known a method in which a coloring material capable of color development is applied and the C, M, and Y coloring layers are arranged in parallel or in layers. Thereby, a display device capable of full-color color development is obtained. For example, black can be displayed by mixing C, M, and Y. Moreover, white can be displayed by making each pigment transparent in a decolored state and making the background color white. As described above, the EC display element is a reflective display element that can electrically repeat color development / decoloration without using a color filter. It is excellent in the point.

  As one of the materials constituting the color developing layer, research on a material called a π-electron conjugated polymer has been advanced. There are various types of π-electron conjugated polymers such as polyacetylene, polypyrrole, polyaniline, polyparaphenylene vinylene, polythiophene, polymer light emitting diode (thin film display), solid state lighting, organic photovoltaic cell, memory device. It is promising as a material for constituting organic field effect transistors, printed electronics, conductors, lasers, sensors, solid capacitors and the like. Some of these π-electron conjugated polymers exhibit electrochromic properties, and such a material may be a material constituting the color developing layer of the EC display element described above. In order to obtain an EC display device capable of full color development by the above-described color development / decoloration of C, M, and Y using the electrochromic properties of the π electron conjugated polymer, the electrochromic of the π electron conjugated polymer is used. The characteristics must be changed from C, M, and Y coloring states to colorless.

  On the other hand, the EC display element shows a color change by developing / decoloring due to the EC characteristics of the π-electron conjugated polymer. At this time, an oxidation or reduction reaction is performed simultaneously with the EC of the π-electron conjugated polymer. When the entire EC display element is considered, it is considered that the counter reaction needs to occur. For example, an EC display element is formed by forming ITO (indium tin oxide) as a transparent electrode, a π-electron conjugated polymer formed thereon, a solvent containing a supporting electrolyte, and a π-electron conjugated polymer. When the π-electron conjugated polymer is decolored by oxidation, it is a counter reaction of the entire EC display element when it is formed with a configuration of an electrode facing the display electrode (hereinafter sometimes abbreviated as a counter electrode). Since there is no substance that can cause a reduction reaction, there is a possibility that the solvent or the supporting electrolyte may be destroyed.

  In response to these problems, by providing a substance that can store a certain amount of charge on the counter electrode, it is possible to gain capacitance and compensate for electron transfer associated with oxidation / reduction of π-electron conjugated polymers. Has been attempted (see Patent Document 1). As another example, an organic radical compound such as 2,2,6,6-tetramethylpiperidine-1-oxyl (hereinafter sometimes abbreviated as TEMPO) derivative is formed on the counter electrode, and π Attempts have been made to compensate for electron transfer associated with oxidation / reduction of an electronic conjugated polymer (see Patent Document 2).

  However, as described in Patent Documents 1 and 2, when it is attempted to compensate for the movement of electrons accompanying oxidation / reduction of the π-electron conjugated polymer with capacitance or an organic radical compound, the oxidation / reduction of the π-electron conjugated polymer is performed. There remains a problem that the speed of electron movement accompanying the reduction cannot be followed, charge compensation by the counter electrode becomes rate-determining, and the response speed of the entire EC display element is lowered.

  As described above, in order to compensate for the electron transfer accompanying the oxidation / reduction of the π-electron conjugated polymer, it is desirable to provide the same kind of material on the counter electrode. Most of the chromic characteristics show a color change between the coloring states, and even a material that changes color from the above-described coloring state to a colorless color is extremely limited. For example, 2,3-dihydrothieno [3,4-b] [1,4] dioxin (hereinafter sometimes abbreviated as EDOT), 1H-thieno [3,4-d] imidazol-2 (3H) -one (Hereinafter, it may be abbreviated as TIO.) And the like. That is, in the oxidized and reduced states, if the charge compensation layer is not colorless, the color of the π-electron conjugated polymer functioning as the color developing layer is disturbed by the coloring on the counter electrode, and the EC display element as a whole is desired. It was difficult to obtain color development.

  On the other hand, in recent years, carbon nanotubes (hereinafter sometimes abbreviated as CNT) have attracted attention as conductive materials. However, both CNT and π-electron conjugated polymers have π-π stacks due to the abundance of π electrons. It was known to interact with each other (see Patent Document 5 and Non-Patent Document 1). According to the above document, it is said that a π-electron conjugated polymer such as polyalkylthiophene can be allowed to interact with CNT by dispersing the CNT in a solution by ultrasonic treatment. Yes. It is considered that a π-electron conjugated polymer / CNT composite is formed by the interaction between the π-electron conjugated polymer and the CNT. It has also been known that an EDOT / CNT composite can be obtained by electrochemical polymerization from an electrolyte solution containing EDOT and CNT (see Non-Patent Document 2).

  As a result of these, in Patent Document 5, it is considered that a π-electron conjugated polymer / CNT complex is formed by contact of the selective light-absorbing substance and CNT, thereby increasing the absorbance. Yes. In Non-Patent Document 1, the absorption spectrum of the π-electron conjugated polymer / CNT complex is said to be slow. In Non-Patent Document 2, the absorption spectrum of the π-electron conjugated polymer / CNT complex is The absorption maximum was supposed to shift. As described above, it has been suggested that as a result of the interaction between the π-electron conjugated polymer and the CNT, some change is observed in the absorption spectrum of the composite. However, there has been no description of a composition containing π-electron conjugated polymer and CNT having a compound represented by 1H-thieno [3,4-d] imidazol-2 (3H) -one or the like as a structural unit. .

JP-A-7-134318 JP 2008-51947 A JP 2008-31430 A JP 2008-7771 A JP 2004-115778 A

Organic Letters 2006, vol.8, No.24, p.5489-5492 Macromolecular Rapid Communications 2008, vol.29, p.1959-1964

  The present invention has been made to solve the above problems, and is suitable as a charge compensation layer for electrodes of organic electronics and electrochromic display elements, particularly for counter electrodes, and a π-electron conjugated polymer and carbon nanotubes are used. It aims at providing the transparent composition containing.

［式中、Ｘは、硫黄原子であり、Ｙは、酸素原子であり、Ｚは、それぞれ独立して水素原子及び置換基を有してもよい炭素数１〜２０の有機基からなる群から選択される少なくとも１種である。］
で示される化合物を構成単位とするπ電子系共役重合体、及びカーボンナノチューブを含む組成物であって、π電子系共役重合体１００質量部に対するカーボンナノチューブの配合量が０．０１〜２０質量部であることを特徴とする組成物を提供することによって解決される。 The above problem is solved by the following general formula (1):

[Wherein, X is a sulfur atom , Y is an oxygen atom, and Z is independently a hydrogen atom and a group consisting of organic groups having 1 to 20 carbon atoms which may have a substituent. At least one selected. ]
A composition comprising a π-electron conjugated polymer comprising a compound represented by formula (1) and a carbon nanotube, wherein the compounding amount of the carbon nanotube per 100 parts by mass of the π-electron conjugated polymer is 0.01 to 20 parts by mass. It is solved by providing a composition characterized in that

［式中、Ｘ、Ｙ及びＺは前記と同義である。］
で示される化合物、支持電解質及びカーボンナノチューブを含む溶液を電気化学的に重合することを特徴とする前記組成物の製造方法が本発明の好適な実施態様である。 At this time, the following general formula (1):

[Wherein, X, Y and Z are as defined above. ]
A method for producing the composition is characterized by electrochemically polymerizing a solution containing a compound represented by the formula (1), a supporting electrolyte and carbon nanotubes.

［式中、Ｘ、Ｙ及びＺは前記と同義である。］
で示される化合物、酸化剤及びカーボンナノチューブを含む溶液を化学酸化重合することを特徴とする前記組成物の製造方法が本発明の好適な実施態様である。 At this time, the following general formula (1):

[Wherein, X, Y and Z are as defined above. ]
A method for producing the composition, which comprises chemically oxidatively polymerizing a solution containing a compound represented by formula (1), an oxidizing agent and carbon nanotubes, is a preferred embodiment of the present invention.

  At this time, a film made of the composition of the present invention is a preferred embodiment of the present invention, and a counter electrode laminate in which the film is formed on the counter electrode is a preferable embodiment of the present invention. An electrochromic display element including the counter electrode laminate is also a preferred embodiment of the present invention.

  The composition containing a π-electron conjugated polymer and carbon nanotubes according to the present invention can be suitably used for an electrode of an organic electronics element. In particular, since a colorless and transparent state can be maintained during electrochemical changes due to oxidation and reduction, it can be more suitably used as a charge compensation layer for a counter electrode of an electrochromic display element.

It is the figure which showed the structure of the electrochromic display element concerning suitable embodiment of this invention. 2 is a diagram showing electrochromic characteristics of a film made of a π-electron conjugated polymer / carbon nanotube composition in Example 1. FIG. It is the figure expanded to the vertical axis | shaft direction by making the maximum value of the light absorbency in FIG. 2 into 0.1. 2 is a diagram showing a cyclic voltammogram of a film made of a π-electron conjugated polymer / carbon nanotube composition in Example 1. FIG. 6 is a diagram showing a cyclic voltammogram of a film made of a polymer having 1H-thieno [3,4-d] imidazol-2 (3H) -one as a structural unit in Comparative Example 2. FIG.

  The present invention comprises a compound represented by the following general formula (1) as a structural unit, and a π-electron conjugated polymer having a structure in which the 2,5-position carbon atoms of the thiophene ring of the structural unit are bonded to each other, and carbon A composition containing nanotubes, wherein the compounding amount of carbon nanotubes per 100 parts by mass of the π-electron conjugated polymer is 0.01 to 20 parts by mass. In the present invention, the term “transparent” means a state in which the visible light transmittance at a film thickness of 100 to 500 nm is 70% or more. Further, in the present invention, the term “colorless” refers to a state in which coloring is not visually recognized. Details will be described below.

［式中、Ｘは、酸素原子、硫黄原子、−ＮＨ−及び−ＮＲ^１−（Ｒ^１は置換基を有してもよい炭素数１〜２０のアルキル基又は置換基を有してもよい炭素数６〜２０のアリール基である）からなる群から選択される少なくとも１種であり、Ｙは、酸素原子又は硫黄原子であり、Ｚは、それぞれ独立して水素原子及び置換基を有してもよい炭素数１〜２０の有機基からなる群から選択される少なくとも１種である。］

[Wherein, X represents an oxygen atom, a sulfur atom, —NH— and —NR ¹ — (R ¹ may have a C 1-20 alkyl group which may have a substituent or a substituent. Is an aryl group having 6 to 20 carbon atoms), Y is an oxygen atom or a sulfur atom, and Z each independently has a hydrogen atom and a substituent. It may be at least one selected from the group consisting of organic groups having 1 to 20 carbon atoms. ]

In the above general formula (1), X has an oxygen atom, a sulfur atom, —NH—, and —NR ¹ — (R ¹ has an optionally substituted alkyl group having 1 to 20 carbon atoms or a substituent. Is an aryl group having 6 to 20 carbon atoms), Y is an oxygen atom or a sulfur atom, and Z is independently a hydrogen atom and a substituent. It is 1 type selected from the group which consists of a C1-C20 organic group which may have a group.

Here, R ¹ in —NR ¹ — in X is an optionally substituted alkyl group having 1 to 20 carbon atoms or an optionally substituted aryl group having 6 to 20 carbon atoms. . The alkyl group having 1 to 20 carbon atoms which may have a substituent may be linear or branched. Specific examples of the alkyl group having 1 to 20 carbon atoms include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n -Pentyl group, isopentyl group, neopentyl group, tert-pentyl group, n-hexyl group, isohexyl group, 2-ethylhexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, etc. It is done. Moreover, as said C6-C20 aryl group, a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group etc. are mentioned, for example. Among these, R ¹ is preferably an alkyl group having 1 to 20 carbon atoms which may have a substituent, and more preferably an alkyl group having 1 to 10 carbon atoms which may have a substituent. preferable.

  In the above general formula (1), X is preferably an oxygen atom or a sulfur atom, and more preferably a sulfur atom, from the viewpoints of availability of raw materials and ease of production.

  In the general formula (1), Y is an oxygen atom or a sulfur atom, and Y is preferably an oxygen atom from the viewpoint of availability of raw materials.

  In General formula (1), Z is 1 type each independently selected from the group which consists of a C1-C20 organic group which may have a hydrogen atom and a substituent. Z may be the same as or different from each other. Examples of the organic group having 1 to 20 carbon atoms that may have a substituent include bonds other than carbon-carbon bonds such as ether bond, ester bond, amide bond, sulfonyl bond, urethane bond, and thioether bond in the structure. It may be contained, and a double bond, a triple bond, an alicyclic hydrocarbon, a heterocyclic ring, an aromatic hydrocarbon, a heteroaromatic ring and the like may be contained. Furthermore, you may have substituents, such as a halogen atom, a hydroxyl group, an amino group, a cyano group, and a nitro group. Examples of the organic group having 1 to 20 carbon atoms that may have a substituent include an alkyl group having 1 to 20 carbon atoms that may have a substituent and 2 to 2 carbon atoms that may have a substituent. 20 alkenyl groups, optionally substituted aryl groups having 6 to 20 carbon atoms, optionally substituted cycloalkyl groups having 3 to 20 carbon atoms, optionally substituted carbon atoms It may have 3 to 20 cycloalkenyl groups, an optionally substituted alkoxy group having 1 to 20 carbon atoms, an optionally substituted acyl group having 2 to 20 carbon atoms, and a substituent. It has an arylalkyl group having 7 to 20 carbon atoms, an alkylsilyl group having 3 to 20 carbon atoms which may have a substituent, an alkoxycarbonyl group having 2 to 20 carbon atoms which may have a substituent, and a substituent. The C1-C20 heteroaromatic ring group etc. which may be mentioned are mentioned.

As the alkyl group having 1 to 20 carbon atoms, the alkyl group having 1 to 20 carbon atoms exemplified in the description of R ¹ above can be used similarly.

  Examples of the alkenyl group having 2 to 20 carbon atoms include a vinyl group, an allyl group, a methylvinyl group, a propenyl group, a butenyl group, a pentenyl group, and a hexenyl group.

  Examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group.

  Examples of the cycloalkyl group having 3 to 20 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a cycloundecyl group, and a cyclododecyl group. Etc.

  Examples of the C3-C20 cycloalkenyl group include a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, and a cyclohexenyl group.

  Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, and n-pentyl. Oxy group, isopentyloxy group, neopentyloxy group, n-hexyloxy group, isohexyloxy group, 2-ethylhexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy Groups and the like.

  Examples of the acyl group having 2 to 20 carbon atoms include acetyl group, propionyl group, butyryl group, isobutyryl group, benzoyl group, dodecanoyl group, and pivaloyl group.

  Examples of the arylalkyl group having 7 to 20 carbon atoms include a benzyl group, a phenethyl group, and a diphenylmethyl group.

  Examples of the alkylsilyl group having 3 to 20 carbon atoms include a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a tert-butyldimethylsilyl group, and a tert-butyldiphenylsilyl group.

  Examples of the alkoxycarbonyl group having 2 to 20 carbon atoms include methoxycarbonyl group, ethoxycarbonyl group, 2,2,2-trichloroethoxycarbonyl group, n-propoxycarbonyl group, isopropoxycarbonyl group, allyloxycarbonyl group, n-butoxycarbonyl group, isobutoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, pentyloxycarbonyl group, hexyloxycarbonyl group, heptyloxycarbonyl group, octyloxycarbonyl group, benzyloxycarbonyl group, etc. It is done.

  Examples of the C1-C20 heteroaromatic ring group include thienyl group, furyl group, pyridyl group, imidazolyl group, pyrazinyl group, oxazolyl group, thiazolyl group, pyrazolyl group, benzothiazolyl group, benzimidazolyl group and the like. .

  Among these, Z is preferably a hydrogen atom or an optionally substituted alkyl group having 1 to 20 carbon atoms, particularly when Z is a hydrogen atom. It is preferable because the transparency of the π-electron conjugated polymer is excellent. Moreover, it is preferable that all Z are the same substituents.

  The method for obtaining the compound represented by the general formula (1) used in the present invention is not particularly limited, and for example, 2,5-dibromothiophene can be suitably synthesized as a starting compound. Hereinafter, using 2,5-dibromothiophene as a starting compound, 1H— represented by the formula (1a) when X in the compound represented by the general formula (1) is a sulfur atom, Y is an oxygen atom, and Z is a hydrogen atom A method for obtaining thieno [3,4-d] imidazol-2 (3H) -one will be described with reference to the following chemical reaction formula (I).

  As shown in the chemical reaction formula (I), first, by adding a solution in which concentrated sulfuric acid is added to 2,5-dibromothiophene to a mixed acid (fuming nitric acid and fuming sulfuric acid), the 3rd and 4th positions are nitro. To obtain 2,4-dibromo-3,4-dinitrothiophene converted to 3,4-diaminothiophene dihydrochloride which is hydrochloride using hydrochloric acid and tin (Sn) is preferably employed. The Further, by using a base such as sodium carbonate for the obtained hydrochloride, 3,4-diaminothiophene is obtained and reacted with urea, whereby 1H-thieno [3,4] represented by the formula (1a) is obtained. -D] Imidazole-2 (3H) -one can be obtained.

  The CNT used in the present invention is produced by an arc discharge method, a chemical vapor deposition method (hereinafter sometimes abbreviated as a CVD method), a laser ablation method, etc., and is obtained by any method. There may be. In addition, a single-walled carbon nanotube (hereinafter referred to as SWCNT) in which a single carbon film (graphene sheet) is wound in a cylindrical shape and a multi-layer in which two or more graphene sheets are wound in a concentric shape on CNTs. Although there is a carbon nanotube (hereinafter referred to as MWCNT), both SWCNT and MWCNT are used in the present invention. In particular, SWCNT has a diameter smaller than that of MWCNT (that is, the volume per SWCNT is smaller than that of MWCNT). Therefore, even if the volume density occupied by CNT is the same, SWCNT has a larger number density of CNT than MWCNT. Therefore, since the area where the π-electron conjugated polymer and the CNT are in contact with each other increases, SWCNT is preferable for the present invention.

  When SWCNT and MWCNT are produced by the above method, fullerene, graphite, and amorphous carbon are simultaneously generated as by-products, and catalyst metals such as nickel, iron, cobalt, and yttrium also remain. It is preferred to purify the impurities.

  Further, the length of the CNT used in the present invention is not particularly limited, but a composition containing a π-electron conjugated polymer and CNT is short to improve the dispersion of the CNT in the π-electron conjugated polymer. In order to improve the electric conductivity and the ability to compensate for the charge associated with oxidation / reduction of the π-electron conjugated polymer of the coloring layer, it is preferable to use a long one. For example, when the average length of CNT is preferably 2 μm or less, more preferably 0.5 μm or less, the dispersibility of CNT in the π-electron conjugated polymer is enhanced. Since CNTs are generally formed in a string shape, in order to use short CNTs, it is preferable to cut them into short fiber shapes. On the other hand, for example, when a CNT having an average length of 2 μm or more is used, the conductivity of the composition containing the π-electron conjugated polymer and the CNT is increased.

  As a method for purifying the above impurities and cutting into short fibers, it is effective to perform sonication together with acid treatment with nitric acid, sulfuric acid, etc., and using a separation with a filter in addition to improve purity. preferable. A polar substituent such as a carboxyl group may be introduced onto the CNT by the acid treatment, but this polar substituent is present on the CNT from the viewpoint of strongly interacting with the π-electron conjugated polymer in the present invention described later. It is also a preferred embodiment of the present invention that polar substituents such as carboxyl groups are introduced.

  In the present invention, not only cut CNTs but also CNTs prepared in a short fiber shape in advance are preferably used. Such short fibrous CNTs form a catalytic metal such as iron or cobalt on a substrate, and thermally decompose carbon compounds at 700 to 900 ° C. by CVD on the surface thereof to vapor-phase grow the CNTs. It is obtained in a shape oriented in the vertical direction. The short fiber CNTs thus produced can be taken out by a method such as peeling off from the substrate. In addition, the short fibrous CNTs can be obtained by supporting a catalytic metal on a porous support such as porous silicon or an anodic oxide film of alumina and growing the CNTs on the surface by the CVD method. Using oriented molecules such as iron phthalocyanine containing a catalytic metal in the molecule as a raw material, CVD is performed in a gas flow of argon / hydrogen to produce oriented short fiber CNTs. be able to.

  Although the diameter of CNT used by this invention is not specifically limited, Preferably it is 1 nm or more and 100 nm or less, More preferably, it is 50 nm or less.

  The amount of CNT used in the present invention is 0.01 to 20 parts by mass with respect to 100 parts by mass of the π-electron conjugated polymer. When the blending amount of CNT is less than 0.01 parts by mass, the effect of the specific interaction between the π-electron conjugated polymer and CNT when the π-electron conjugated polymer and CNT are combined is low, There is a possibility that the composition containing the π-electron conjugated polymer and the CNT cannot be oxidized / reduced while maintaining transparency. That is, the composition containing the π-electron conjugated polymer and CNT may be colored during the reduction. The blending amount of CNT is preferably 0.1 parts by mass or more. On the other hand, when the compounding amount of CNT exceeds 20 parts by mass, the composition containing the π-electron conjugated polymer and the CNT is colored black, which impairs transparency and lacks strength when formed on the electrode. As a result, there is a risk that it will be peeled off from the electrode. The blending amount of CNT is preferably 10 parts by mass or less.

  The method for producing the composition containing the π-electron conjugated polymer and CNT of the present invention is not particularly limited, and a solution containing the compound represented by the general formula (1), the supporting electrolyte, and the carbon nanotube is electrochemically used. It is preferably produced by polymerization. Specifically, a π-electron conjugated polymer having the compound as a constituent unit on an electrode by electrochemically polymerizing a solution represented by the general formula (1), a supporting electrolyte, and carbon nanotubes, And a film made of a composition containing carbon nanotubes.

  Here, examples of the solvent used for the solution containing the compound represented by the general formula (1), the supporting electrolyte, and the carbon nanotube include nitromethane, acetonitrile, propylene carbonate, nitrobenzene, cyanobenzene, o-dichlorobenzene, dimethylsulfo. Examples thereof include oxide, γ-butyrolactone, dimethyl ether, and water. In addition, as the supporting electrolyte, for example, cations such as ions of alkali metals such as lithium ions, potassium ions, sodium ions, and quaternary ammonium ions, perchlorate ions, boron tetrafluoride ions, phosphorus hexafluoride ions, halogen atoms Examples include using a supporting electrolyte composed of a combination with anions such as ions, arsenic hexafluoride ions, antimony hexafluoride ions, sulfate ions, and hydrogen sulfate ions.

Other examples of the solution containing the supporting electrolyte include, for example, ammonium ions such as imidazolium salts and pyridinium salts; phosphonium ions; inorganic ions; halogen ions and the like as cations. A compound in which the compound (monomer component) represented by the above general formula (1) is dissolved in an ionic liquid in which these cations and anions are combined using fluorine ions such as fluoride ions and triflate. It can also be used.
The content of the compound (monomer component) represented by the general formula (1) in the solution containing the supporting electrolyte can be appropriately set depending on the polymerization reaction conditions to be employed, but is preferably 0.001 to 10 mol. / L, more preferably 0.01 to 1 mol / L, and still more preferably 0.01 to 0.1 mol / L. Moreover, as content rate of the supporting electrolyte in the said electrolyte solution, Preferably it exists in the range of 0.01-10 mol / L, More preferably, it exists in the range of 0.1-5 mol / L.

  Here, as a method for adding CNT to the solution, it may be added directly to the solution containing the supporting electrolyte, or an appropriate amount of CNTs dispersed in advance in another solvent may be added. Since CNT has a strong cohesive force, a method of adding an appropriate amount of CNTs dispersed in a separate solvent in advance is used rather than adding CNT directly to a solution containing a supporting electrolyte. As a method for dispersing CNT in another solvent, it is a known technique that CNT can be dispersed in a solvent by using a minute amount of a dispersible additive such as a soluble conductive polymer, deoxyribonucleic acid, cyclodextrin, or soluble fullerene. Known and applicable.

  The electrode material used in the present invention is not particularly limited, and examples thereof include metals such as platinum, gold, nickel, and silver; conductive polymers; ceramics; semiconductors; conductive carbides such as carbon and conductive diamond; Metal oxides such as indium tin oxide, ATO (antimony doped tin oxide), AZO (aluminum doped zinc oxide), and ZnO (zinc oxide) can be used.

  Here, in the electrochemical polymerization, the voltage at the time of applying the voltage can be appropriately set depending on the polymerization reaction conditions and the like to be adopted, but is preferably within a range of −3 to 3 V, and −1.5 More preferably, it is in the range of -1.5V. As temperature at the time of applying a voltage, it is preferably in the range of 0 to 80 ° C, and more preferably in the range of 15 to 40 ° C.

  The composition containing the π-electron conjugated polymer and the carbon nanotube may be composed only of the π-electron conjugated polymer and CNT having the compound represented by the general formula (1) as a structural unit, Other components may be contained as long as the performance as a transparent material for the counter electrode is not hindered. Examples of such other components include compounds having chromic properties due to redox such as viologen and derivatives thereof, Prussian blue and derivatives thereof, tungsten oxide and derivatives thereof, and the like.

  The method for producing a composition containing a π-electron conjugated polymer and a carbon nanotube of the present invention is not particularly limited, and a chemical oxidative polymerization of a solution containing the compound represented by the above general formula (1), an oxidizing agent and a carbon nanotube. It is suitably manufactured by doing. Specifically, a π-electron conjugated polymer having the compound as a structural unit on an electrode by chemically oxidative polymerization of a solution containing the compound represented by the general formula (1), an oxidant, and carbon nanotubes, and carbon It is preferably manufactured by forming a film made of a composition containing nanotubes.

The oxidizing agent is not particularly limited as long as it is an oxidizing agent composed of a transition metal salt typified by ferric chloride (FeCl ₃ ). For example, iron (III) chloride hydrate, copper perchlorate, Examples thereof include iron perchlorate, ferric p-toluenesulfonate, and ferric salt of diisopropylnaphthalenesulfonate. When polymerizing by chemical oxidative polymerization, an anion derived from the oxidizing agent used can be used as it is as a dopant. For example, in the case of the oxidizing agent, Cl ⁻ for ferric chloride and iron (III) chloride hydrate, ClO ₄ ⁻ for copper perchlorate and iron perchlorate, p-toluenesulfonic acid For ferric and diisopropyl naphthalene sulfonic acid ferric salts, the sulfonate anion will be used as the dopant.

Such dopant is not particularly limited, for _{^{example, PF 6 -, SbF 6 -}} , AsF 6 - , etc. Group 5B element halide anions of; BF ₄ ^- and halogenated anions of 3B group elements; I ^- Halogen anions such as (I ₃ ⁻ ), Br ⁻ and Cl ⁻ ; halogen acid anions such as ClO ₄ ⁻ ; metal halide anions such as AlCl ₄ ⁻ , FeCl ₄ ⁻ and SnCl ₅ ⁻ ; nitric acid represented by NO ₃ ⁻ Anion; sulfate anion represented by SO ₄ ^2- ; p-toluenesulfonate anion, naphthalenesulfonate anion, sulfonate anions such as CH ₃ SO ₃ ⁻ and CF ₃ SO ₃ ^— ; CF ₃ COO ⁻ and C ₆ H ₅ etc. and modified polymers having the above anionic species in the main chain or side chain can be cited; ^- COO a carboxylic acid anion . A dopant may be used individually by 1 type and may use 2 or more types together.

  The chemical oxidative polymerization is preferably performed in the presence of a solvent. Examples of such solvents include saturated aliphatic or alicyclic hydrocarbons such as pentane, hexane, heptane, octane, nonane, decane, and cyclohexane; aromatic carbonization such as benzene, toluene, ethylbenzene, propylbenzene, xylene, and ethyltoluene. Hydrogen: dimethyl ether, ethyl methyl ether, diethyl ether, dipropyl ether, butyl methyl ether, t-butyl methyl ether, dibutyl ether, tetrahydrofuran, 1,4-dioxane and the like ethers; dimethylacetamide, dimethylformamide, N-methyl-2 -Aprotic polar solvents such as pyrrolidone and dimethyl sulfoxide; halogen solvents such as carbon tetrachloride, chloroform and methylene chloride. The said solvent may be used individually by 1 type, or may use 2 or more types together. Among these, the solvent is preferably a halogen solvent or ether. The amount of the solvent used is preferably in the range of 1 to 100 ml and more preferably in the range of 2 to 70 ml with respect to 1 mmol of the compound represented by the general formula (1).

  As a method for adding CNT to the solution during the chemical oxidative polymerization, it may be added directly to the solution, or an appropriate amount of CNTs dispersed in advance in another solvent may be added. Since CNT has a strong cohesive force, a method of adding an appropriate amount of CNTs dispersed in advance in a different solvent is preferably used rather than adding it directly to a solution. As a method for dispersing CNT in another solvent, it is a known technique that CNT can be dispersed in a solvent by using a minute amount of a dispersible additive such as a soluble conductive polymer, deoxyribonucleic acid, cyclodextrin, or soluble fullerene. Known and applicable.

  A preferred embodiment of the composition containing the π-electron conjugated polymer and the carbon nanotube of the present invention described above is a film made of the composition. A counter electrode laminate in which the film is formed on the counter electrode is also a preferred embodiment of the present invention.

  The composition containing the π-electron conjugated polymer and the carbon nanotube of the present invention can be suitably used for an electrode of an organic electronics element, and more preferably used as a charge compensation layer for a counter electrode of an electrochromic display element. Can do. A preferred embodiment of the electrochromic display element is an electrochromic including a counter electrode laminate in which a layer of a film made of a composition comprising the π-electron conjugated polymer of the present invention and a carbon nanotube is formed on a counter electrode. It is a display element. Hereinafter, an electrochromic display element will be described with reference to FIG. 1 as a preferred embodiment.

  As shown in FIG. 1, an example of an EC display element that is the basis of the present invention is, in order from the viewing side, a first insulating substrate 1 (transparent), a display electrode (first electrode layer) 2 (transparent), and a color. Layer (EC layer) 3, electrolyte layer 4 (transparent), π-electron conjugated polymer / carbon nanotube composition layer 8 (transparent) formed on the counter electrode (second electrode layer) 5, second insulating property A substrate 6 (a material with high reflectivity) is formed. At this time, the layer formed of the counter electrode 5 and the π-electron conjugated polymer / carbon nanotube composition layer 8 is a counter electrode laminate. That is, in the EC display element shown in FIG. 1, the display electrode 2 and the counter electrode 5 are arranged to face each other, and the color developing layer 3 and the electrolyte layer 4 are sandwiched between the two electrodes. The display electrode 2 and the coloring layer 3, the coloring layer 3 and the electrolyte layer 4, and the electrolyte layer 4 and the π-electron conjugated polymer / carbon nanotube composition layer 8 formed on the counter electrode 5 are in direct contact. ing. The spacer 7 is formed so as to surround the coloring layer 3 and the electrolyte layer 4 and controls the distance between the electrodes to a predetermined distance. In the present embodiment, the spacer 7 also functions as an adhesive layer, and bonds the display electrode 2 and the counter electrode 5 or the first insulating substrate 1 and the second insulating substrate 6. The color developing layer 3 is one in which a reversible oxidation-reduction reaction occurs when an electric field is applied, and color development / decoloration associated therewith occurs.

  Since the first insulating substrate 1 needs to be able to visually recognize the coloring layer 3 from an observer, it needs to be transparent, and specifically has a total light transmittance of 70% or more. More preferably, it has a total light transmittance of 80% or more. As the first insulating substrate 1, a glass substrate, polystyrene (PS), polymethyl methacrylate (PMMA), styrene-methyl methacrylate copolymer (MS), polycarbonate (PC), cycloolefin polymer (COP), cycloolefin A resin substrate such as a copolymer (COC), polyethylene terephthalate (PET), or polyethylene naphthalate (PEN) can be used.

  The display electrode 2 needs to be transparent for the same reason as described above, and desirably has a total light transmittance of 70% or more. More preferably, it has a total light transmittance of 80% or more. The display electrode 2 is made of a generally used metal oxide such as indium-tin oxide (ITO), aluminum-doped tin oxide (ATO), antimony-doped zinc oxide (AZO), or zinc oxide (ZnO). A transparent conductive film may be used. Further, conductive carbides such as single wall carbon nanotubes (SWCNT) and double wall carbon nanotubes (DWCNT), high conductivity such as poly (ethylene-3,4-dioxythiophene) (PEDOT), polyaniline derivatives, polypyrrole derivatives, etc. You may use what laminated | stacked the molecule | numerator thinly to such an extent that the transmittance | permeability is not reduced.

  For the coloring layer 3, a π-electron conjugated polymer derived from a π-electron conjugated monomer is used. The π-electron conjugated monomer is not particularly limited as long as it is a compound that can be formed into a film by electrochemical polymerization, but acetylene, p-phenylene, p-phenylene oxide, p-phenylene sulfide, p-phenylene vinylene, naphthylene vinylene, Thianaphthene, pyrrole, thiophene, thiophene vinylene, alkylthiophene, ethylenedioxythiophene, propylenedioxythiophene, aniline, perinaphthalene, oxadiazole, thiazyl, acene, furan, alkylfuran, selenophene, tellurophene, aminopyrene, phenanthrene, imidazole , Oxazole, thiazole, pyrazole, isoxazole, isothiazole, pi-electron conjugated monomer having benzotriazole structure, pi-electron conjugated monomer having fluorene structure A π-electron conjugated monomer having a structure capable of introducing a boron atom into the main chain, a π-electron conjugated monomer in which a part of the carbon of an aromatic ring represented by pyridine, pyridazine, pyrimidine, pyrazine, and quinoline is substituted with nitrogen, Examples thereof include π-electron conjugated monomers in which a part of carbon of an aromatic ring represented by pyran is substituted with oxygen, and derivatives thereof.

The electrolyte layer 4 may be any form of electrolyte. For example, in the case of a solution, since the ionic conductivity is large, the response speed, the driving voltage / current can be reduced. Further, a highly reliable element that does not leak can be provided if it is in a gel or solid state. The solution electrolyte is an organic solvent such as acetonitrile, butyrolactone, propylene carbonate, or tetrahydrofuran, and the supporting electrolyte is a lithium salt such as LiClO ₄ , LiAsF ₆ , LiPF ₆ , or LiBF ₄ , (C ₄ H ₉ ) ₄ N ^+. Ammonium salts such as BF ₄ ⁻ , (C ₄ H ₉ ) ₄ N ⁺ PF ₆ ⁻ , NH ₄ ⁺ BF ₄ ⁻ and NH ₄ ⁺ PF ₆ ⁻ , sulfones such as sodium p-toluenesulfonate and sodium dodecylbenzenesulfonate What dissolved the acid salt etc. can be used.

  As described above, when the supporting electrolyte is included in the electrolyte, the supporting electrolyte concentration may be 0.01 to 5.0 [mol / l] with respect to the organic solvent. When the supporting electrolyte concentration is less than 0.01 [mol / l], ionic conduction is insufficient, and the response speed may be extremely slow. Furthermore, when coloring / decoloring is repeated by applying a forward voltage / reverse voltage, there is a risk of causing problems such as uneven coloring. On the other hand, when the supporting electrolyte concentration exceeds 5.0 [mol / l], the supporting electrolyte tends to be saturated and may be deposited.

  Further, as the electrolyte layer 4, a room temperature molten salt (ionic liquid) may be used for the purpose of improving efficiency and safety. As the ionic liquid, any combination of the following anions and cations can be used. Examples of the anion include compounds having tetrafluoroborate, hexafluorophosphate, bis (trifluoromethylsulfonylimide), bis (pentafluoroethylsulfonylimide), and the like. Examples of the cation include an imidazolium cation such as ethylmethylimidazolium and methylbutylimidazolium, a pyrrolidinium cation such as butylmethylpyrrolidinium, a pyridinium cation such as butylpyridinium, butyltrimethylammonium and diethylmethoxyethylmethylammonium. And compounds having an ammonium cation such as By using an ionic liquid, high-speed response and good memory performance can be realized.

As the solid electrolyte, a solid electrolyte such as Ta ₂ O ₅ or MgF ₂ is used. Further, as the polymer solid electrolyte, a polymer solid electrolyte into which a substituent responsible for ion conduction such as polystyrene sulfonic acid and Nafion (registered trademark) is introduced may be used, or a matrix (matrix) polymer material may be used. You may use what disperse | distributed the supporting electrolyte in it. As the matrix polymer, polyethylene oxide whose main chain units are represented by-(C-C-O) _n -,-(C-C-N) _n- , and-(C-C-S) _n- , Examples include polyethyleneimine and polyethylene sulfide. These may be branched as a main chain structure. Polymethyl methacrylate, polyvinylidene fluoride, polycarbonate, and the like can also be preferably used.

  When forming the electrolyte layer 4 with a solid electrolyte, a required plasticizer may be added to the matrix polymer. As the preferred plasticizer, when the matrix polymer is hydrophilic, water, ethyl alcohol, isopropyl alcohol and a mixture thereof are preferable. When the matrix polymer is hydrophobic, propylene carbonate, dimethyl carbonate, ethylene carbonate, γ-butyrolactone is preferable. Acetonitrile, sulfolane, dimethoxyethane, ethyl alcohol, isopropyl alcohol, dimethylformaldehyde, dimethyl sulfoxide, dimethylacetamide, n-methylpyrrolidone and mixtures thereof are preferred.

The supporting electrolyte dispersed in the matrix polymer includes lithium salts such as LiCl, LiBr, LiI, LiBF ₄ , LiClO ₄ , LiPF ₆ and LiCF ₃ SO ₃ ; potassium salts such as KCl, KI and KBr; NaCl And sodium salts such as NaI and NaBr; or tetraalkylammonium salts such as tetraethylammonium borofluoride, tetraethylammonium perchlorate, tetrabutylammonium borofluoride, tetrabutylammonium perchlorate, and tetrabutylammonium halide. The alkyl chain length of the quaternary ammonium salt (tetraalkylammonium salt) described above may be uneven.

In addition, any coloring material other than the coloring layer 3 formed of a π-electron conjugated polymer can be used in combination with any material as long as it is an electrochromic material. For example, IrOx, NiOx, WO ₃ can be used as inorganic materials. , MoO ₃ , TiO _{2 and the} like. Moreover, nickel phthalocyanine etc. are mentioned as an organic-inorganic composite material.

  In the present invention, the π-electron conjugated polymer / carbon nanotube composition layer 8 is preferably formed on the counter electrode 5. Thereby, in the state of oxidation and reduction, the π-electron conjugated polymer / carbon nanotube composition layer 8 formed on the counter electrode 5 can be maintained in a colorless and transparent state. As a result, since the coloring state of the π-electron conjugated polymer in the coloring layer 3 is not affected, the coloring of the electrochromic display element is improved. Here, the counter electrode 5 may be transparent or opaque, and various metal materials, polymer materials, ceramic materials, semiconductor materials, and other conductive materials can be used. Metal materials are generally preferred due to their high electrical conductivity, such as lithium, beryllium, magnesium, calcium, strontium, barium, boron, aluminum, gallium, indium, tin, silver, gold, copper, nickel, palladium Platinum, chromium, molybdenum, tungsten, manganese, nickel, cobalt and their oxides and combinations or alloys thereof can be used. Of course, the material of the counter electrode 5 is not limited to these. In particular, ITO, gold, silver and copper are more preferably used because they are highly conductive and chemically inert.

  The second insulating substrate 6 may be transparent or opaque, and various materials can be used. For example, a glass substrate such as a quartz glass substrate or a white plate glass substrate, a ceramic substrate, a paper substrate, or a wood substrate can be used as the second insulating substrate 6. Further, the second insulating substrate 6 is not limited to these. Examples of the second insulating substrate 6 include esters such as polyethylene naphthalate and polyethylene terephthalate, cellulose esters such as polyamide, polycarbonate, and cellulose acetate, polyvinylidene fluoride, and poly (tetrafluoroethylene-co-hexa. Fluoropolymers such as fluoropropylene), polyethers such as polyoxymethylene, polyacetal, polystyrene, polyethylene, polypropylene, polyolefins such as methylpentene polymer, and synthetic resin substrates such as polyimides such as polyimide-amide and polyetherimide Can do. When these synthetic resins are used as a substrate, a rigid substrate that does not bend easily can be formed, but a flexible film-like structure can also be formed. Further, when the counter electrode 5 has sufficient rigidity, the second insulating substrate 6 may not be provided.

  Further, between the coloring layer 3 and the electrolyte layer 4, or between the electrolyte layer 4 and the π-electron conjugated polymer / carbon nanotube composition layer 8, or between the π-electron conjugated polymer / carbon nanotube composition layer 8 and A highly reflective material may be laminated between the counter electrode 5, between the counter electrode 5 and the second insulating substrate 6, or on the back surface of the second insulating substrate 6. Thereby, the reflection efficiency of the light incident from the outside can be improved. And the visibility of EC display element can be improved. In particular, it is preferable that the counter electrode 5 is ITO and the second insulating substrate 6 is glass or a film from the viewpoint of material availability and versatility. In this case, the π-electron conjugated polymer / carbon nanotube in the present invention is used. Since the composition layer 8 is transparent, an EC display element can be easily manufactured by laminating a material having a high reflectance such as white on the back surface of the second insulating substrate 6.

Further, an insulating layer may be provided between the display electrode 2 and the counter electrode 5 in order to prevent the electrodes from coming into contact with each other and causing a short circuit. In the present invention, a shape like the spacer 7 is given as an example of a preferred embodiment of the insulating layer. As the insulating layer, any appropriate material that can function as a barrier between electrodes is used. Thereby, an insulating layer can provide an electrical barrier and can prevent an electrical short circuit between electrodes. Therefore, it is desirable that the insulating layer be made of a high resistivity material that is substantially free of pinholes and has an electrical resistance of about 10 ⁸ Ωcm or more, preferably about 10 ¹² Ωcm or more. Suitable high resistivity materials also include, but are not limited to, silicon nitride, boron nitride, aluminum nitride, silicon oxide, aluminum oxide, polyimide, polyvinylidene fluoride, and parylene.

  The method for manufacturing the EC display element is not particularly limited. For example, the first insulating substrate 1, the display electrode 2, the coloring layer 3, the electrolyte layer 4, the counter electrode 5, the second insulating substrate 6, the spacer 7, π Each component member such as the electronic conjugated polymer / carbon nanotube composition layer 8 is prepared individually and assembled to produce an EC display element. Among these, a method in which a layer containing a desired π-electron conjugated polymer is formed in advance on an electrode and an EC display element is manufactured using a member in which the layer and the electrode are integrated is preferable. Since an EC display element can be more easily produced, for example, a π-electron conjugated polymer is polymerized on an electrode serving as an anode by electrolytic polymerization, and the obtained π-electron conjugated polymer film is removed from the electrode. More preferably, the EC display element is manufactured by using it as a constituent member of the EC display element together with the electrode without being removed.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely using an Example, this invention is not limited at all by these Examples.

[Synthesis of 1H-thieno [3,4-d] imidazol-2 (3H) -one represented by the formula (1a)]

  A mixed acid was prepared using 11 ml of fuming nitric acid and 20 ml of fuming sulfuric acid. 7.5 g (31 mmol) of 2,5-dibromothiophene was gradually added dropwise to a solution added with 13 ml of concentrated sulfuric acid, and the mixture was stirred for 3 hours while maintaining the temperature at 20 to 30 ° C. in a water bath. The reaction was stopped by transferring the liquid in the flask to a container containing ice. The obtained solid was separated by filtration and recrystallized from methanol to obtain 2,5-dibromo-3,4-dinitrothiophene. The yield based on 2,5-dibromothiophene was 66%. 12 N concentrated hydrochloric acid was added to the obtained 2,5-dibromo-3,4-dinitrothiophene at a rate of 6.05 ml / mmol. While maintaining the temperature of the obtained solution at 0 ° C. in an ice bath, 7.1 equivalent of tin with respect to 2,5-dibromo-3,4-dinitrothiophene was gradually added thereto, and further 2 hours after the addition. Stir. Thereafter, the produced solid was separated by filtration, and the solid was washed with diethyl ether to obtain 3,4-diaminothiophene dihydrochloride. The yield based on 2,5-dibromo-3,4-dinitrothiophene was 90%.

The ¹ H-NMR measurement result of 3,4-diaminothiophene dihydro-chloride is shown below.
¹ H-NMR (500 MHz, DMSO, TMS) δ: 6.95 (2H, s)

  The obtained 3,4-diaminothiophene dihydrochloride was dissolved in an amount of water corresponding to 4 ml / mmol, and a 4N aqueous sodium carbonate solution corresponding to 2 ml / mmol was gradually added dropwise thereto. After further stirring for 2 hours, the product was separated and extracted into an organic phase using ethyl acetate, and the obtained organic phase was dried over sodium sulfate, and then the solvent was distilled off to remove 3,4-diaminothiophene. Obtained. The yield based on 3,4-diaminothiophene dihydrochloride was 60%.

The ¹ H-NMR measurement result of 3,4-diaminothiophene is shown below.
¹ H-NMR (500 MHz, CDCl ₃ , TMS) δ: 6.17 (2H, s), 3.36 (4H, s)

  1.1 equivalents of urea and amyl alcohol corresponding to 10 ml / mmol were added to 3,4-diaminothiophene obtained, and the reaction was allowed to reflux at 130 ° C. for 5 hours in an argon gas atmosphere. Thereafter, amyl alcohol was distilled off, and the residue was purified by silica gel column chromatography using an ethyl acetate / hexane solvent to obtain 1H-thieno [3,4-d] imidazole-2 (3H represented by the formula (1a)). ) -One was obtained. The yield based on 3,4-diaminothiophene was 55%.

The ¹ H-NMR measurement result of 1H-thieno [3,4-d] imidazol-2 (3H) -one is shown below.
¹ H-NMR (500 MHz, CDCl ₃ , TMS) δ: 6.36 (1H, s)

[Preparation of CNT dispersion]
A single-walled carbon nanotube (hereinafter sometimes abbreviated as CNT) prepared by the arc discharge method was reacted with 63% nitric acid at 85 ° C. for 2 days (wet oxidation), and then purified and recovered by filtration. . Next, 20 mg of the above CNT, sodium dodecylbenzenesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.) 500 mg, and 0.05 g of an aqueous sodium hydroxide solution 100 g were mixed and subjected to ultrasonic irradiation for 1 minute (device name: ULTRASONIC HOMOGENIZER MODEL UH-600SR, SMT) and a CNT dispersion. This CNT dispersion was subjected to circulation filtration with a hollow fiber membrane (pore diameter 200 nm, membrane area 105 cm ² (manufactured by SPECTRUM)). Thereafter, the CNT dispersion was washed with 500 ml of 0.05 M aqueous sodium hydroxide solution to which 0.5 wt% sodium dodecylbenzenesulfonate was added to remove short bundles of CNTs. Thereafter, isopropanol was added to obtain a CNT dispersion having a CNT concentration of 1200 ppm.

Example 1
1 ml containing 0.01 mmol (0.0014 g) 1H-thieno [3,4-d] imidazol-2 (3H) -one and 20 μl of the above CNT dispersion containing 0.1 M tetrabutylammonium perchlorate Was dissolved / dispersed in a propylene carbonate solution. Next, at a temperature of 25 ° C., 100 mV / 100 V in the range of −0.5 to 1.3 V with respect to the silver / silver chloride reference electrode using the anode ITO electrode manufactured by Geomatech and the cathode platinum electrode manufactured by Nilaco. By applying a voltage at an insertion speed of sec and performing electrochemical polymerization, a film composed of a π-electron conjugated polymer / carbon nanotube composition was formed on the ITO electrode.

  Using the obtained film made of the composition, when a voltage of -0.5 V is applied, when coloring is performed (doping), when a voltage of 0.5 V is applied, when intermediate (half-doping), By measuring the UV-Vis spectrum (ultraviolet-visible absorption spectrum) of each state when the voltage of 1.2 V is applied when decoloring (doping), the electrochromic characteristics of the film made of the composition are measured. evaluated. The results are shown in FIGS. As shown in FIG. 2 and FIG. 3, the electrochromic property by oxidation / reduction of the film composed of the π-electron conjugated polymer / carbon nanotube composition produced in Example 1 has a large absorption in the visible light region. No, that is, there was substantially no color change, and it was colorless and transparent.

  In addition, cyclic voltammetry measurement of a film comprising a π-electron conjugated polymer / carbon nanotube composition formed on an ITO electrode was performed on a silver / silver chloride reference electrode using a cathode platinum electrode manufactured by Niraco. The voltage was applied at an insertion speed of 100 mV / sec in the range of -0.5 to 1.3 V, and the oxidation-reduction characteristics were evaluated. The result is shown in FIG. As shown in FIG. 4, it was confirmed from the cyclic voltammogram of the film composed of the π-electron conjugated polymer / carbon nanotube composition produced in Example 1 that an electrochemical change due to oxidation / reduction occurred. It was done.

Example 2
0.02 mmol (0.0028 g) of 1H-thieno [3,4-d] imidazol-2 (3H) -one, 40 μl of the above CNT dispersion, and 1 equivalent (0.0032 g) of ferric chloride (FeCl _3). ) Was added to 1 ml of chloroform and reacted by stirring at room temperature for 30 minutes to obtain a film composed of a π-electron conjugated polymer / carbon nanotube composition. Using the obtained film made of the composition, when a voltage of -0.5 V is applied, when coloring is performed (doping), when a voltage of 0.5 V is applied, when intermediate (half-doping), By measuring the UV-Vis spectrum (ultraviolet-visible absorption spectrum) of each state when the voltage of 1.2 V is applied when decoloring (doping), the electrochromic characteristics of the film made of the composition are measured. Visual evaluation was made. The electrochromic characteristics by oxidation / reduction of the film composed of the π-electron conjugated polymer / carbon nanotube composition produced in Example 2 were substantially colorless and transparent.

Comparative Example 1
0.01 mmol (0.0014 g) of 2,3-dihydrothieno [3,4-b] [1,4] dioxin (hereinafter sometimes abbreviated as EDOT) and 20 μl of the above CNT dispersion were mixed with 0.1 M Dissolved / dispersed in 1 ml of propylene carbonate solution containing tetrabutylammonium perchlorate. Next, a voltage at an insertion speed of 100 mV / sec in the range of −0.5 to 1.3 V with respect to the silver / silver chloride reference electrode using the anode ITO electrode made by Geomatic and the cathode platinum electrode made by Niraco Was applied and electrochemically polymerized to form a film composed of a π-electron conjugated polymer / carbon nanotube composition on the ITO electrode. On the other hand, EDOT is dissolved in a 0.1 M tetrabutylammonium perchlorate / propylene carbonate solution at a concentration of 0.01 M, and a silver / silver chloride reference electrode using a Geomatek anode ITO electrode and a Nilaco cathode platinum electrode. On the other hand, a polymer film made of EDOT is formed on the ITO electrode by applying a voltage at a pulling rate of 100 mV / sec in the range of -1.0 to 1.0 V and electrochemically polymerizing it. I let you. There is no difference in the electrochemical characteristics and optical characteristics of the films obtained by the two methods described above, and Example 1 using 1H-thieno [3,4-d] imidazol-2 (3H) -one. In comparison, it was confirmed that the π-electron conjugated polymer and the carbon nanotube did not show a specific interaction.

Comparative Example 2
Dissolve 0.01 mmol (0.0014 g) of 1H-thieno [3,4-d] imidazol-2 (3H) -one in 1 ml of propylene carbonate solution containing 0.1 M tetrabutylammonium perchlorate. / Dispersed. Next, a voltage at an insertion speed of 100 mV / sec in the range of −0.5 to 1.3 V with respect to the silver / silver chloride reference electrode using the anode ITO electrode made by Geomatic and the cathode platinum electrode made by Niraco Was applied and electrochemically polymerized to form a 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer film on the ITO electrode.

  A voltage was applied to the silver / silver chloride reference electrode at a pulling rate of 100 mV / sec to the silver / silver chloride reference electrode using this membrane and a Niraco cathode platinum electrode, and oxidation-reduction Characteristics and visual electrochromic characteristics were evaluated. The result is shown in FIG. As shown in FIG. 5, the cyclic voltammogram of the film made of a polymer having 1H-thieno [3,4-d] imidazol-2 (3H) -one as a constituent unit produced in Comparative Example 2 was carried out. Although it showed the same tendency as the cyclic voltammogram in Example 1, the electrochromic property by oxidation / reduction changed from dark blue to gray. Therefore, as in Example 1, the 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer and the carbon nanotube do not specifically interact and remain substantially colorless. It was shown that no electrochemical oxidation / reduction change occurred (the colorless and transparent state could not be maintained during the electrochemical change due to oxidation / reduction).

Comparative Example 3
According to the method for preparing the CNT dispersion, a CNT dispersion having a CNT concentration of 6 ppm was prepared, and 0.01 mmol (0.0014 g) of 1H-thieno [3,4-d] imidazol-2 (3H) -one and the above 20 μl of 6 ppm CNT dispersion was dissolved / dispersed in 1 ml propylene carbonate solution containing 0.1 M tetrabutylammonium perchlorate. Next, a voltage at an insertion speed of 100 mV / sec in the range of −0.5 to 1.3 V with respect to the silver / silver chloride reference electrode using the anode ITO electrode made by Geomatic and the cathode platinum electrode made by Niraco Was applied and electrochemically polymerized to form a film composed of a π-electron conjugated polymer / carbon nanotube composition on the ITO electrode.

  A voltage was applied to the silver / silver chloride reference electrode at a pulling rate of 100 mV / sec to the silver / silver chloride reference electrode using this membrane and a Niraco cathode platinum electrode, and oxidation-reduction Characteristics and visual electrochromic characteristics were evaluated. The cyclic voltammogram of the composition comprising 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer and carbon nanotubes produced in Comparative Example 3 has the same tendency as the cyclic voltammogram in Example 1 However, the electrochromic properties due to oxidation / reduction changed from dark blue to gray. Therefore, as in Example 1, the 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer and the carbon nanotube do not specifically interact and remain substantially colorless. It was shown that no electrochemical oxidation / reduction change occurred (the colorless and transparent state could not be maintained during the electrochemical change due to oxidation / reduction). This is because the content of CNT with respect to 100 parts by mass of 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer is less than 0.01 parts by mass, and 1H-thieno [3,4- d] This is probably because the effect of the specific interaction between the imidazole-2 (3H) -one polymer and the carbon nanotube was low.

Comparative Example 4
According to the procedure of Example 1, an attempt was made to prepare a π-electron conjugated polymer / carbon nanotube composition in the same manner except that 0.3 ml was used instead of 20 μl of 1200 ppm CNT dispersion. The deterioration of the dispersion state of the CNTs and the blackening due to the CNTs were remarkable and were not suitable for evaluation. This is because the content of CNT with respect to 100 parts by mass of 1H-thieno [3,4-d] imidazol-2 (3H) -one polymer exceeds 20 parts by mass. It was shown that it is not preferable because it is likely to impair the performance.

DESCRIPTION OF SYMBOLS 1 1st insulating substrate 2 Display electrode 3 Coloring layer 4 Electrolyte layer 5 Counter electrode 6 2nd insulating substrate 7 Spacer 8 (pi) electron system conjugated polymer / carbon nanotube composition layer (charge compensation layer)

Claims (6)

The following general formula (1):

[Wherein, X is a sulfur atom , Y is an oxygen atom, and Z is independently a hydrogen atom and a group consisting of organic groups having 1 to 20 carbon atoms which may have a substituent. At least one selected. ]
A composition comprising a π-electron conjugated polymer comprising a compound represented by formula (1) and a carbon nanotube, wherein the compounding amount of the carbon nanotube per 100 parts by mass of the π-electron conjugated polymer is 0.01 to 20 parts by mass. The composition characterized by these. The following general formula (1):

[Wherein, X, Y and Z are as defined above. ]
2. The method for producing a composition according to claim 1, wherein the solution containing the compound represented by the above, the supporting electrolyte and the carbon nanotube is electrochemically polymerized. The following general formula (1):

[Wherein, X, Y and Z are as defined above. ]
2. The method for producing a composition according to claim 1, wherein a solution containing the compound represented by the formula: oxidant and carbon nanotube is chemically oxidatively polymerized.   A film comprising the composition according to claim 1.   A counter electrode laminate in which the film according to claim 4 is formed on a counter electrode.   An electrochromic display element comprising the counter electrode laminate according to claim 5.

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