JPH01210470A - Conductive material and its production - Google Patents

Abstract

PURPOSE:To produce a conductive material excellent in transparency without detriment to its insulating property and the shape and appearance of a support, by completely dissolving a polymeric material and a specified complex in a good solvent, applying the solution to an insulating support and drying it. CONSTITUTION:1 pt.wt. polymeric material comprising at least one member which is adhesive to an insulating support and selected from among a polyester resin, an acrylic resin, a vinyl chloride/vinyl acetate copolymer resin and an ethylene/vinyl acetate copolymer resin together with 0.05-4 pts.wt. 7,7,8,8- tetracyanoquinodimethane complex is dissolved in a solvent containing a good solvent for this complex to prepare a paint for a transparent conductive layer, and this paint is applied to an insulating support and dried to form a transparent layer. Because said complex is precipitated as needle crystals, a very thin conductive layer can be formed; therefore a conductive material of excellent transparency can be obtained without detriment to the shape and appearance of the insulating support.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a conductive material having a transparent conductive coating on the surface of an electrically insulating support and a method for producing the same.

(Prior Art) With the development of the electronic industry in recent years, semiconductor elements such as ICs and LSIs have become highly integrated, and although their functionality has improved, they have also become more susceptible to damage by electrostatic discharge.

Therefore, transparent conductive packaging materials are used to store and transport electronic components and circuits using these semiconductors while protecting them from static electricity. On the other hand, with mass production, most of the housings of electronic equipment products incorporating these semiconductor elements have shifted to plastic, and in particular, most of the housings of small electronic equipment have been replaced with plastic. Because the plastic housing has long edges, it is easily charged with static electricity, and countermeasures against static electricity have become a major theme. In addition, plastic casings are transparent to electromagnetic waves, so as electronic circuits become more densely packed and operate at higher frequencies, electromagnetic shielding measures have become an important issue. It is expected that it will appear.

In addition, with the remarkable development in the field of electric photodetectors, the field of display materials such as electroluminescence, liquid crystals, solid displays such as electrochromic, electrophotographic recordings such as OHP films, slide films, and microfilms, and electrostatic recording media. It is expected that it will be used as a conductive layer.

Conventionally, methods for making the surface of an insulating material conductive include the use of conductive paints, surfactants, and vapor deposition of metals, metal oxides, and the like. Among these, conductive paints that use carbon powder, metal powder, etc. as fillers are composites in which carbon powder or metal powder is mixed into polymers, and although they are relatively durable, they lack transparency and are difficult to coat. It has the disadvantage of damaging the appearance of the workpiece. Furthermore, since surfactants are ionic conductors, they cannot provide effective antistatic effects under environmental conditions that require antistatic measures, that is, conditions with low relative humidity, and conversely, under conditions with high relative humidity. The surface is sticky and the performance is unstable.

In addition, the vapor deposition of metals, especially metal oxides such as ITO (indium-tin oxide), can provide sufficient transparency and conductivity, but the vapor deposition equipment is extremely expensive, and as a result, processing Tubes become expensive.

(Problems to be Solved by the Invention) The present invention has been made against the background of the above-mentioned conventional technical problems, and aims to provide electrical conductivity without impairing the original strength or appearance of the support, and The object of the present invention is to provide a conductive material having a transparent conductive layer whose conductivity is not dependent on humidity and having good adhesion to a support.

(Means for Solving the Problems) As a result of various studies to solve the above problems, the present inventors found that polyester resins, acrylic resins, vinyl chloride-vinyl acetate resins, and polyester resins, which have adhesive properties with electrically insulating supports, and vinyl chloride-vinyl acetate resins. A polymeric material consisting of one or more of copolymer resins, ethylene-vinyl acetate copolymer resins, and ? , 7.8.8-tetrasif/ki/dimethane complex (hereinafter abbreviated as TCNQ complex) is dissolved in a good solvent to prepare a transparent conductive layer coating, and the transparent conductive layer coating is applied onto the electrically insulating support. , coating, spraying,
Alternatively, after uniformly adhering by dipping or other method, the good solvent is distilled off to form a transparent conductive layer having a structure in which fine needle-like crystals of the TCNQ complex are precipitated in the polymer material in the form of a network. This has made it possible to produce a conductive material without impairing the strength or appearance of the electrically insulating support. The present applicant has previously applied for a method for manufacturing a conductive material using a silicone resin, a urethane resin, or a vinyl chloride resin as a polymeric material having adhesive properties. It has improved characteristics.

To explain the present invention in more detail, the electrically insulating support used in the present invention is a molded body containing a film sheet made of a general-purpose polymeric material, glass, wood, paper, ceramic, or the like. General-purpose polymer materials include, but are not particularly limited to, polyethylene, polyvinyl chloride, polypropylene,
Examples include polyethylene terephthalate, polycarbonate, polyvinylidene heptadide, polytetrafluoroethylene, polyurethane, and polyimide. The surface of the electrically insulating support is subjected to corona discharge treatment, flame treatment, ozone treatment, or brimer treatment to further enhance the adhesion between the electrically insulating support and the adhesive polymer material. Those that have been subjected to this can also be used.

The polymer materials that are adhesive to the electrically insulating support used in the present invention include epoxy, phenol, acrylic, polyester, alkyd, urethane, silicone, synthetic rubber, vinyl chloride, and vinyl acetate. system, vinyl chloride-
There are resins based on vinyl acetate copolymer and ethylene-vinyl acetate copolymer, but considering the adhesion with the support, thin film formability, and transparency, and the stability of the TCNQ complex in the resin, , polyester-based, acrylic-based, vinyl chloride-vinyl acetate copolymer-based, and ethylene-vinyl acetate copolymer-based resins are desirable. In addition, in order to improve film properties, these resins are modified by introducing hydrophobic groups such as silicone or 70-roalkyl groups, or functional groups such as carboxyl groups or hydroxyl groups. can do. Furthermore, if necessary, two or more of these resins may be mixed, or a crosslinking agent such as incyanate or tyrolmelamine may be mixed.

The TCNQ complex used in the present invention is a type of charge transfer complex, and is composed of an electron donor and an electron acceptor, and the electron acceptor is TCNQ. Examples of electron donors include fulvalenes containing chalcogen in their skeleton, typified by tetrathiafulvalene (TTF);
Examples include quaternary ammonium typified by tetramethylammonium, and compounds in which the N-position of a heterocyclic nitrogen compound typified by quinoline and isoquinoline is substituted with an alkyl group.

Considering thermal stability, electrical conductivity, and ease of crystal precipitation, among these electron donors, quinoline, isoquinoline, naphthoquinoline, 2.2'-bibylinor, 4.4'-
Bipyridyl or a compound in which the N-position thereof is substituted with an alkyl group having 1 to 8 carbon atoms is preferred, and more preferably a compound in which the N-position of quinoline or isoquinoline is substituted with an alkyl group having 1 to 8 carbon atoms. That is, preferred TCNQ complexes include, for example, N-methylquinolinium-TCNQ complex, N-
Methylinquinolinium-TCNQ complex, N-ethylquinolinium-TCNQ complex, N-ethylquinolinium-TCNQ complex, Nn-probylquinolinium-TCNQ complex, N-n-probylquinolinium-TCNQ complex,
TCNQ complex, N-n-probylisoqui/linium-T
CNQ complex, N-1so-propylquinolinium-TC
NQ complex, N-1so-propyl ink/linium-T
CNQ complex, N-'-butylki/linium-TCNQI
i-form, Nn-1so-butylisoquinolinium-TCN
Q complex, N-n-amilky/linium-TCNQ complex, N-n-7milky/linium-TCNQ complex, N
1so-amylquinolinium-TCNQ complex, N-
1so-amyl quinolinium-TCNQ complex, N-
1 n-octylquinolinium-TCNQ complex, N-n
-Octyl isoto/linium-TCNQ complex. The TCNQ complexes exemplified above are particularly suitable in the present invention, but the TCNQ complexes in the present invention are not limited in any way by these examples.

T using quinoline or isoquinoline compounds as electron donors
The CNQ complex exhibits high conductivity due to the mixed valence state of TCNQ. For this purpose, TC in the present invention
The NQ complex preferably contains 1 mol or more of TCNQ per 1 mol of the electron donor, preferably 0.1 to 10% by weight of the Q neutral molecule.
is preferably added in addition to the TCNQ complex.

A method for manufacturing a conductive material in the present invention will be explained.

Polymer material and TC that are adhesive to electrically insulating support
A conductive layer coating material is prepared by dissolving the NQ complex in a good solvent in an amount of 0.05 to 4 parts by weight, more preferably 0.1 to 4 parts by weight, of the TCNQ complex per 1 part by weight of the polymer material.

After this conductive layer paint was uniformly deposited on the electrically insulating support using a method such as coating, spraying or dipping,
A conductive material having a transparent conductive layer on the surface of the electrically insulating support can be obtained by drying at a temperature of ~300° C., preferably 50° C. to 150° C., under normal pressure or reduced pressure. or,
In order to improve various physical properties of the conductive layer of the conductive material thus obtained, aging can be carried out by means such as heating and leaving.

Furthermore, the transparent conductive layer paint in which the polymeric material and TCNQ complex of the present invention are dissolved in a good solvent can be processed by methods such as spraying using a roll-to-talley method and dipping method, similar to the surface processing when using a general paint.

The good solvent used in the present invention is a good solvent for TCNQ complex (,)
A mixed solvent of (b) and a good solvent for polymeric materials is used, and a single solvent may be used as long as it is a good solvent for both.In general, in paints containing polymeric binders, a good film can be obtained. Therefore, it is possible to add a solvent in which the polymeric binder is difficult to dissolve as a diluent.

TCNQ complexes generally have high solubility in strong polar solvents. As the good solvent (a) in the present invention, acetonitrile, acetone, benzonitrile, dimethylformamide, dimethylacetamide, and dimethylsulfoxide are preferred from the viewpoint of stability after dissolution and ease of precipitation of needle-like crystals when forming a conductive layer. .

The good solvent (b) diluent is generally aromatic hydrocarbons such as the polymeric material, esters such as ethyl acetate and butyl acetate, ketones such as acetone and methyl ethyl ketone, ethyl alcohol, isopropyl alcohol, etc. One type or a mixture of two or more types of alcohols, ethers such as isopropyl ether and dioxane, and aliphatic hydrocarbons such as cyclohexane and hexane can be used.

(Examples) The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples. In addition, the evaluation method of the conductive material described in the following examples is as follows.

(1) Surface resistivity is based on JIS K-6911,
(2) Transmittance was measured at 550 nI11 using a Hitachi model Ll-3200 self-recording spectrophotometer.

(3) Adhesion was measured by a cross-cut cellophane tape peel test. That is, cutting lines reaching the support are placed on the transparent conductive layer at intervals of 11 mm, and the width is 1-m2.
Make 100 square squares, and express the number of squares that are not there as a percentage to determine the adhesion.

Example 1 1 part by weight of N-n-butylisoquinolinium-TCNQ complex, 5 parts by weight of TCNQO1O, and polyester resin (Tanushi Seisaku, Chemitsu) K-1089, solid content 100%
) 2 parts by weight, N,N-dimethylacetamide 30 parts by weight, methyl ethyl ketone 2.3 parts by weight, toluene 2 parts by weight
．． Polyethylene terephthalate film (manufactured by Yojin Co., Ltd., 75 μm, S type, transmittance 8) was completely dissolved in a mixed solvent consisting of 3 parts by weight and 62.35 parts by weight of butyl acetate.
1.5% (hereinafter abbreviated as PET film) using a #8 bar coater, and dried at 100° C. to obtain a transparent conductive film. The surface resistivity of this film is 8.
8X10'Ω/hole, light transmission Example 2 N-11-butylisoquinolinium T CN Q
1 part by weight of the complex, and polyester O (fat (manufactured by Toshi),
乍MITSUTO-1089, solid content 100%) 3 weight BW
It was dissolved in a mixed solvent consisting of 25 parts by weight of sN+N'-dimethylformamide and 71 parts by weight of acetone. A slide glass was immersed in this solution and then dried at 150°C to obtain a conductive glass. Surface resistivity is 2.3X10
1Ω/mouth, the light transmittance was 93.6%. Moreover, the adhesion degree was 85%.

Example 3 1 part by weight of N-n-butylisoquinolinium-TCNQCN, 5 parts by weight of TCNQ O, and vinyl chloride-
1.5 parts by weight of vinyl acetate copolymer resin (manufactured by Cemedine Co., Ltd., Cemedine 181, solid content 30%), 35 parts by weight of dimethyl sulfoxide and 63.45 parts by weight of acetonitrile.
A polypropylene film (Chisso iJ, $4
The surface of 0FAK, 40μ (0, unstretched, transmittance 87.6%) was #×105Ω/hole, and the light transmittance was 82.1%.

Moreover, the adhesion was 100%.

Example 4 1 part by weight of N-n-butylisoquinolinium-TCNQCN, 0.05 part by weight of TCNQ, and vinyl chloride-
3 parts by weight of vinyl acetate copolymer (fat (manufactured by Cemedine Co., Ltd., Cemedine 181, solid content 30%) was dissolved in a mixed solvent consisting of 30 parts by weight of dimethylformamide, 22.95 parts by weight of benzonitrile, and 45 parts by weight of butyl acetate. This solution was then transferred to a PET film (manufactured by others, 6 um,
The film was coated on the surface of the film (transmittance: 83.7%) using a reverse coater, and then dried at 120° C. to obtain a transparent conductive film. Surface resistivity is 1.8X106
Ω/mouth, and the transmittance was 77.7%. Moreover, the adhesion was 100%.

It was placed in a thermostatic chamber set at 70% RH, 30° C., and 25% R1-1, and the surface resistivity was measured. As a result, the surface resistivity at 20° C. and 70% RH was 1.8×10 6 Ω/hole, and the surface resistivity at 30′C and 125% RH was also 1.8×1+ohm/hole.

Examples 6-1O TC on N-n-amyl quinolinium-TCNQCN
NQ, acrylic resin (Soken Chemical 5tJ-100A,
N, N'
- A mixed solvent of methylformamide and butyl acetate
It was dissolved according to the composition shown in the table. PET film (manufactured by others, 50
μs, H8 type.

The conductive film was coated on the film (transmittance: 87.3%) using a #8 bar tool and dried at 150°C to obtain a conductive film.

The surface resistivity and transmittance are shown in Table 1. Adhesion was 100% in all cases. Further, FIG. 1 shows the relationship between the ratio of resin components to TCNQCN and surface resistivity.

Examples 11-16 N-iso-7 milisoquinolinium-TCNQ complex,
TCNQ and an ethylene-vinyl acetate copolymer resin (manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd., Nurex BH) were dissolved in a mixed solvent of N,N'-dimethylformamide, toluene, and butyl acetate in the composition shown in Table 2.

This was applied to the surface of a commercially available polyethylene bag (manufactured by Seisaku Nippon Sha Co., Ltd., Univac) using a #8 bar coater, and dried at 60°C to obtain a conductive bag. The relationship between the ratio of the resin component to the obtained conductive complex and the surface resistivity is shown.

Comparative Example 1 1 part by weight of Nn-butylisoqui7linium TCNQ complex, 1 part by weight of TCNQ 0105, and 1 part by weight of silicone O (fat (KS-772, manufactured by Shin-Etsu Chemical Co., Ltd.), 17.5 parts by weight of methyl ethyl ketone, 20 parts by weight of toluene, n
- Hebutane 10.5 parts by weight, a transmittance (λ=550n
m) 87.3%) using a #8 bar coater and air-dried to obtain a conductive film. The surface resistivity of this film is 3.8 x 106Ω/hole, and the transmittance is 83
．． It was 0%. Adhesion was 60%.

Comparative Example 2 Nn-butylisoqui/linium-TCNQ complex 1.0
4 parts by weight, 53 parts by weight of TCNQ O, 053 parts by weight, and 1.2 parts by weight of urethane resin (AD335A manufactured by Toyo Morton Co., Ltd.), 2.6 parts by weight of 1,4-dioxane, 45 parts by weight of 7C nitrile, and 50 parts by weight of dimethylformamide. completely dissolved in a mixed solvent consisting of 1. This is a 40 μm polypropylene film (manufactured by Chisso, #40FAK, unstretched, transmittance (λ = 550n) whose surface has been subjected to corona discharge treatment.
m) 87.6%) using a #8 bar coater, and dried with warm air to obtain a conductive film. The surface resistivity of this film was 4.6×10 5 Ω/hole, and the transmittance was 83.9%. Adhesion was 75%.

1) E ・'1゛Comparative Example 3's; 7N-iso-probylkihanium-TCNQ
1 part by weight of the complex and 2 parts by weight of polyvinyl chloride were dissolved in 100 parts by weight of dimethylformamide.

This solution was transferred to a 50 μm transparent polyethylene terephthalate film (manufactured by Music University, HS type, transmittance (λ = 55).
(0 nm) 87.3%) using a #8 bar coater and dried with warm air to obtain a conductive film. The surface resistivity of this film is 8.7 x 105Ω/hole,
The transmittance was 79.4%.

Moreover, the adhesion was 60%.

(Effects of the Invention) The electrical conductivity of the electrically conductive material of the present invention is expressed by the precipitation of fine acicular crystals of the TCNQ complex in a network in the transparent conductive layer of the electrically conductive material. It is an electronic conductor, and its conductivity has no humidity dependence. Further, after completely dissolving the TCNQ complex and the polymeric material in a good solvent, it became possible to obtain an electrically conductive material with excellent electrically insulating transparency without impairing the shape or appearance of the electrically insulating support. Furthermore, by changing the mixing ratio of the TCNQ complex and the polymer material, it has become possible to arbitrarily set the surface resistivity of the conductive material in the range of 104 to 1012 Ω/hole.

[Brief explanation of the drawing]

FIGS. 1 and 2 show the relationship between the ratio of the resin component to the TCNQ complex constituting the transparent conductive layer of the conductive material of the present invention and the surface resistivity of the conductive material. Patent applicant Nippon Carlit Co., Ltd.'IP31 Figure TCN (Ratio of resin component of l complex to 'f' resin component 12)

Claims (3)

[Claims] 1. In a conductive material in which a transparent conductive layer is provided on an electrically insulating support, the transparent conductive layer is a polyester resin, an acrylic resin, or a vinyl chloride-vinyl acetate copolymer resin that has adhesive properties with the electrically insulating support. , a composite of a polymeric material consisting of one or more of ethylene-vinyl acetate copolymer resins and a 7,7,8,8-tetracyanoquinodimethane complex, the 7,7,8 , 8-tetracyanoquinodimethane complex is 0.0 part by weight of the polymer material.
5 to 4 parts by weight of an electrically conductive material. 2. In a method for producing a conductive material in which a transparent conductive layer is provided on an electrically insulating support, a polyester resin, an acrylic resin, a vinyl chloride-vinyl acetate copolymer resin, an ethylene resin, which has adhesive properties with the electrically insulating support, - 1 part by weight of a polymeric material consisting of one or more types of vinyl acetate copolymer resins together with 0.05 to 4 parts by weight of a 7,7,8,8-tetracyanoquinodimethane complex, After dissolving the 7,8,8-tetracyanoquinodimethane complex in a solvent containing a good solvent to prepare a transparent conductive layer coating, and coating the transparent conductive layer coating on the electrically insulating support. . A method for producing a conductive material comprising the steps of drying to form a transparent conductive layer. 3. 3. The method for producing a conductive material according to claim 2, wherein the good solvent contains at least one or more of acetonitrile, acetone, benzonitrile, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide.