JPH01236273A - Organic conductive composition - Google Patents

Abstract

PURPOSE:To provide the title composition excellent in film forming property, moldability, conductivity, etc., by adding a surfactant or a silicone oil to a system comprising a polymeric compound, a 7,7,8,8-tetracyanoquinodimethane complex and an organic solvent. CONSTITUTION:A polymer compound (A) (e.g., polyacrylonitrile or polymethyl methacrylate) is mixed with a 7,7,8,8-tetracyanoquinodimethane complex (B), a surfactant (e.g., polyoxyethylene nonylphenyl ether) or a silicone oil (C) and an organic solvent (D) which can dissolve components A, B and C (e.g., dimethylformamide) to produce an organic conductive composition. When this conductive composition is made into a conductor, the use of component C makes it possible to inhibit the crystal growth of component B in component A and to exhibit high conductivity in spite of being in a substantially dissolved state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an organic conductive composition, and specifically relates to a polymer compound, 7,7,8.8-tetracyanoquinodimethane The present invention relates to a conductive composition with excellent film-forming properties and moldability, which is characterized by adding a surfactant to a system consisting of a complex salt (abbreviated as TCNQ) and an organic solvent.

This composition can be used in conductive pastes, electronic circuits, capacitors,
Heat-sensitive elements, electromagnetic shielding paints, antistatic films,
It can be applied to applications such as conductive paper and conductive coating agents.

[Prior art]

As conductive compositions, those containing a cationic polymer as a main composition and those containing metal or carbon dispersed in a polymer are widely known. However, the former has drawbacks such as a low conductivity level and high hygroscopicity, and the latter has problems with smoothness and transparency when made into a film.

On the other hand, as a conductive composition using TCNQ,
Compositions consisting of a polymer having a nitrogen cationic group and T C and N Q, and (2) a composition consisting of a polymer compound and an organic low-molecular complex salt of TGNQ are known.

Regarding ■, its solubility in organic solvents is very poor;
Since it can only be dissolved in highly polar solvents such as dimethylformamide, its uses are extremely limited and it cannot be said to be practical.

Regarding ■, please refer to JP-B No. 44-16499,
-12375, JP-A No. 54-130651, etc., but there are limitations on film formability and formability when forming extremely thin films of 50 μm or less, especially 10 μm or less, or on usable solvents. etc. cannot be said to be fully satisfactory. That is, when these compositions are made thicker, they become a 5-layer film, but there remains a problem with the uniformity of the surface. This film has a rough surface and a mottled pattern, making it impractical.

Conventionally, in order to impart high conductivity, it was considered undesirable to mix a conductive organic component (in the present invention, the complex salt of TCNQ) and a polymer compound in a state close to a completely dissolved state (especially 1973-130650), JP-A-58
-34841, in order to form a film with high conductivity, three TCNQ complex salts are added to a polymer compound.
It is proposed that the crystals should be formed as thin needle-like or fiber-like crystals in a dimensional network.

That is, conventionally, it was thought that TCNQ complex salt crystals grow in a polymer compound, and the more they overlap, the more the conductivity improves. However, when such a material is made into a film, the compatibility between the polymer compound and the TCNQ complex salt is poor;
The surface transparency and smoothness are insufficient, especially when the film thickness is 50 μm.
When the following thin films are formed, there are problems in film formability, such as the formation of portions where no film is formed, and it is difficult to say that they can be applied to applications that require microfabrication. Furthermore, when TCNQ complex crystals exist in the film, it is not only impossible to make the film thinner than the size of the crystals, but also the refractive index of the polymer compound and the refractive index of the TCNQ complex crystals are different. Because they are different, transparency inevitably becomes insufficient.

[Problem to be solved by the invention]

The present invention is an organic conductor composition that improves the compatibility between a polymer compound and a TCNQ complex salt, has excellent film formability and formability, and the obtained film is highly transparent and flexible, and also exhibits high conductivity. The purpose is to provide something.

[Means to solve the problem]

In order to achieve the above object, in the organic conductor composition of the present invention, a surfactant is further present in the system consisting of a polymer compound, a TCNQ complex salt, and an organic solvent. As a result, TCNQ complex salt can be dispersed in a polymer compound with extremely small crystals virtually dissolved, making it an organic conductor that can form ultra-thin conductive films with smooth surfaces and conductors that require microfabrication. It was possible to make a composition.

The present invention has been achieved based on this knowledge.

That is, the organic conductor composition according to the present invention comprises (a) a polymer compound, (b) 7,7,8,8-tetracyanoquinodimethane complex salt, (c) a surfactant or silicone oil, and (d) It is characterized by being made of an organic solvent that can dissolve the three substances (a), (b), and (C) above.

This will be explained in detail below.

There are no particular restrictions on the polymer compound, but polymethacrylate, polyacrylate, polyacrylonitrile, polyacrylonitrile, polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl acetal,
Polyvinylidene fluoride, polyethylene oxide, polyester, polycarbonate, polyvinyl carbazole, polyvinylpyrrolidone, polysulfone, polyphenylene sulfide, polyimide resin, polyparabanic acid,
Polyurethane, phenolic resin, silicone resin, etc. can be used alone or as a mixture. It is also possible to use a copolymer of the vinyl polymer compound. Particularly preferred polymer compounds are film-forming and coating film-forming polymer compounds.

The ratio of the polymer compound to the organic solvent varies depending on the type of combination of the polymer compound and the organic solvent, or the usage situation, but in general, the ratio of the polymer compound to 100 parts by weight of the organic solvent is 0.1 to 90 parts by weight. Preferably 0.5-70
Used in parts by weight.

Regarding TCNQ complex salts, see J. Am., Chem.
Soc.

It is reported in detail in Dan 3374 (1962),
In the present invention, it is preferable to use a complex salt represented as Do.TCNQ-.TCNQ'.

As for D+, an organic cation shown in the following formula can be used.

(Left below) 舒Phe -P"-Phe (R1, R,, R, is H or an alkyl group having 1 to 12 carbon atoms, R2 is H or an alkyl group having 1 to 30 carbon atoms, benzyl group , phenylethyl group) In addition, T of the oligomer having a quaternary nitrogen cationic group
CNQ salts can also be used.

The amount of TCNQ complex salt is 1 to 100 parts by weight of the polymer compound.
It is used in an amount of 90 parts by weight, preferably 5 to 50 parts by weight.

As component (c) such as a surfactant, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, fluorinated surfactants, silicones, etc. are used, but especially non-ionic surfactants are used. Preferred are ionic surfactants, nonionic fluorosurfactants, and silicones such as methyl silicone, dimethyl silicone, and methyl phenyl silicone.

The amount of component (C) such as surfactant added is 1
0.001 to 20 parts by weight, preferably o, oos to 5 parts by weight for fluorosurfactants, and 0.05 to 10 parts by weight for other surfactants.

Examples of organic solvents include amides such as dimethylformamide, nitriles such as acetonitrile, alcohols such as methanol, ethanol, butanol, ketones such as cyclohexanone and methyl ethyl ketone, cellosolves such as methoxyethyl acetate and methoxyethanol, butyl acetate, Esters such as amyl acetate, ethers such as ethylene glycol dimethyl ether, aromatic hydrocarbons such as toluene and xylene, and halogenated hydrocarbons such as diglormethane and trichlene are used.

These organic solvents may be used alone or in combination.

The composition is prepared by adding the polymer compound, TCNQ complex salt, and surfactant to an organic solvent and completely dissolving the mixture at room temperature or by heating and stirring. If solid content precipitates at room temperature, use it separately.

〔Effect of the invention〕

When a conductor is produced using the composition according to the method of the present invention, crystal growth of TCNQ complex salt in a polymer compound is suppressed, and high conductivity is exhibited even though the TCNQ complex salt is in a virtually dissolved state. .

Therefore, when the composition of the present invention is used, a highly conductive material with excellent film formability and moldability can be obtained, resulting in a smooth, transparent film with a thickness of 50 mm.
It is particularly advantageous for the production of ultra-thin films of micrometers or less, especially 10 micrometers or less, and the production of electrical conductors that require microfabrication.

Example I 1.0 g of N-butylisoquinolinium TCNQ complex salt, 5.0 g of polyacrylonitrile, 45 g of dimethylformamide, and polyoxyethylene nonylphenyl ether (Emulgen 903 manufactured by Kao Corporation) 0.25
g and stirred and dissolved at room temperature. The obtained green varnish was cast onto a glass plate and dried at 100°C. Smooth surface resistance value of the surface with a film thickness of 5 μm3. OX 103Ω/
Oral films were obtained. In addition, the film was examined under a microscope.
When enshrined, no crystal formation was observed (crystal size 5 μm or less).

Example 2 N-decylquinolinium TCNQ complex salt 0
．． 6 g, 2.0 g (1:1) copolymer of methyl methacrylate and n-butyl acrylate, 40 g ethanol
, 20 g of acetonitrile, 30 g of cyclohexanone, and 0.05 fluorine surfactant FC-431 (manufactured by 3M)
g was dissolved under stirring at room temperature. After filtering off insoluble solids, the filtrate was cast onto a glass plate and dried at 100°C. Smooth surface resistance value of 1 μm film thickness: 1.5 x 10'
A transparent film of Ω/mouth was obtained. Furthermore, when the film was observed under a microscope, no crystal formation was observed (
(crystal size 5 μm or less).

Example 3 N-hexylisoquinolinium TCNQ complex salt 1 g, polymethyl methacrylate 5. Og, n-butanol sog, 20 g of acetonitrile, 30 g of methyl ethyl ketone, and 0.34 g of silicone oil (KP341 manufactured by Shin-Etsu Silicon Co., Ltd.) were dissolved with stirring at room temperature. The obtained green varnish was cast onto a glass plate and dried at 100°C.

Smooth surface resistance value of 3μm film thickness 6,0XIO'Ω
/ A transparent film of the mouth was obtained. Note that when the film was observed under a microscope, no crystal formation was observed (crystal size: 5 μm or less).

Example 4 0.4 g of N-butyl-α-picolinium TCNQ complex salt, AS resin (Stylac AS manufactured by Asahi Kasei Corporation)
-967), 86 g of cyclohexane, 10 g of acetonitrile, and 0.2 g of sorbitan monolaurate (Rheodol SP-LIO manufactured by Kao Corporation) were dissolved with stirring at room temperature. The obtained green varnish was cast onto a glass plate and dried at 100°C.

Smooth surface resistance value of 1 μm film thickness 4.5 x 10
A transparent film of 7 Ω/hole was obtained. In addition, when the vA of the film was observed under a microscope, no crystal formation was observed (crystal size: 5 μm or less).

Example 5 3.0 g of N-benzylpyridinium/TCNQ complex salt, 10 g of polycarbonate, 70 g of dimethylformamide, 27 g of dioxane, and 0.02 g of fluorosurfactant FC-431 (manufactured by 3M) were dissolved with stirring at room temperature. The resulting green varnish is cast onto a glass plate,
It was dried at 100°C.

Smooth surface resistance value of 10 μm film thickness8. OX10
'Ω/mouth film was obtained. Note that when the film was observed under a microscope, no crystal formation was observed (crystal size: 5 μm or less).

Example 6 N-dodecylquinolinium TCNQ complex salt 0.3 g, polyvinyl butyral 1.5 g, butanol 30 g, acetonitrile 5 g, methyl ethyl ketone 4
0g, 20g of ethoxyethanol and polyoxyethylene lauryl ether (Emulgen-104P manufactured by Kao Corporation)
0.07 g was dissolved under stirring at room temperature. The obtained green varnish was cast onto a glass plate and dried at 100°C. Smooth surface resistance value of 1 μm or less film thickness 6.5 x 1
A film of 0''Ω/hole was obtained. When the film was subjected to 11NFN under a microscope, no crystal formation was observed.

Comparative Example 1 A film was formed using a varnish prepared in the same manner as in Example 2 without using a fluorosurfactant, and the surface resistance value was 1. A film of 1×10'Ω/portion was obtained, but the surface had fine irregularities, and when viewed under a microscope,
The formation of crystals of about 20 μm was observed. In addition, some areas where no film was formed were observed.

Comparative Example 2 When a film was formed using a varnish prepared in the same manner as in Example 3 without using silicone oil, a film with a surface resistance value of 3.4 x 10'Ω/hole was obtained, but the surface The condition shows fine irregularities, and when observed under a microscope,
The formation of crystals of about 50 μm was observed. In addition, some areas where no film was formed were observed.

Claims (1)

[Claims] 1. (a) a polymer compound (b) a 7,7,8,8-tetracyanoquinodimethane complex salt (c) (i) a surfactant or (ii) a silicone oil (d) the above-mentioned An organic conductive composition comprising an organic solvent capable of dissolving three of (a), (b), and (c).