JPH0224299B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Field of Application) The present invention relates to a method for producing a conductive composite made of plastic used, for example, as an IC packaging material. (Prior Art) It has been conventionally known to manufacture conductive composites by using plastic as a base material and subjecting it to conductivity imparting treatment. Taking advantage of the material's characteristics, it is used as a material to prevent static electricity damage, such as in IC packaging materials. Conventional methods for producing conductive composites include a method in which a metal oxide is thinly vapor-deposited onto a plastic film, a method in which a conductive paint containing a metal oxide, etc. is thinly applied to a plastic film, etc., and a method in which a conductive film is formed to form a transparent film. A method of applying a paint to a plastic film, etc., a method of electrolytically oxidizing polymerization of pyrrole to polyvinyl chloride, etc. are known. (Problems to be Solved by the Invention) Most of the above-mentioned conventional methods form a conductive film on the plastic surface, so the bonding stability of the conductive film to the plastic substrate is generally poor, and the conductive film may be damaged by external force. It was not possible to obtain a conductive composite with excellent durability due to drawbacks such as peeling or scratching. According to the electrolytic oxidation polymerization method of pyrrole, conductive polypyrrole can be formed in a plastic base material, but the manufacturing cost is high due to electrolysis, and it requires complicated manufacturing equipment and has a small shape. It can only be applied to plastic substrates in the form of films or sheets, and it can also only be applied to relatively small dimensions, such as those with complex shapes such as molded products, long dimensions, and large products. The disadvantage was that it was difficult to apply. (Means for Solving the Problems) The method for producing a conductive composite of the present invention involves contacting a conductive material made of plastic with a gas phase atmosphere of a monomer capable of forming an electronically conjugated polymer, and generating active energy. The method is characterized by obtaining a conductive composite by irradiating it with radiation. The base resin of the conductive treated material used in the present invention is:
Examples include polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polyethylene, polybutadiene, polystyrene, polycarbonate, nylon, polyetherimide, polyether sulfon, cellophane, polyethylene terephthalate, etc. Generally, materials with poor gas barrier properties are advantageously applied in the present invention. The material to be electrically conductively treated may be a plastic film using the above-mentioned resin as a base resin or a plastic molded product (injection molded product, pressure-pressure vacuum molded product, etc.), and the present invention can be advantageously applied to either case. The thickness of the material to be conductively treated is not particularly limited, but is 5 μm or more.
Preferably, the thickness is 1000 μm. In the present invention, the material to be electrically conductively treated is brought into contact with a gas phase atmosphere of a monomer that can form an electronically conjugated polymer. It refers to a substance that has the following properties and undergoes polymerization when exposed to light energy, and representative examples thereof include five-membered heterocyclic compounds. The 5-membered heterocyclic compound preferably used in the present invention is pyrrole, thiophene, furan, indole or derivatives thereof, such as 3-methylpyrrole, 3-methylthiophene, 3-methylfuran, 3-methylindole. etc., but are not limited to these. The above monomers are dissolved in a suitable solvent,
This monomer solution is heated to generate monomer gas. Alternatively, the monomer gas may be generated from the solid itself. As the above-mentioned solvent, any commonly used organic solvent can be used, such as alcohols such as methanol, ethanol, and butanol, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone,
Ethers such as ethyl ether and tetrahydrofuran, halogenated hydrocarbons such as methylene chloride and chloroform, esters such as ethyl acetate and butyl acetate, aromatic hydrocarbons such as toluene, benzene and xylene, and aliphatic carbons such as hexane. hydrogen,
Examples include nitrogen-containing compounds such as acetonitrile and benzonitrile. In carrying out the present invention, a solvent suitable for the base resin of the material to be electrically conductively treated may be selected from among the above-mentioned solvents, but among the above-mentioned solvents, those with low boiling points are more advantageous in terms of manufacturing conditions. be. In the present invention, irradiation with active energy rays is used as a means for photopolymerizing the gaseous monomer.
Ultraviolet rays are preferred as the active energy rays, and the irradiation time varies depending on the thickness of the material to be electrically conductive treated, the level of electrical conductivity to be imparted, etc., but generally 2
~24 hours is preferred. When irradiating, the material to be electrically conductively treated may be irradiated directly or may be irradiated through a transparent body such as a transparent plate or a transparent container. The concentration of the monomer gas with which the material to be electrically conductively treated comes into contact can be arbitrarily adjusted by adjusting the irradiation time of the active energy rays, etc., but it is usually desirable to set the concentration to 1000 ppm or more. Photopolymerization of the above monomer imparts electrical conductivity to the material to be electrically conductively treated, and it is preferable to perform doping treatment to impart greater electrical conductivity. Doping treatment methods include 1) a method in which a dopant is coated on the surface of the material to be electrically conductively treated as a pretreatment, and 2) a method in which a gaseous dopant is mixed in the resin of the material to be electrically conductively treated together with monomer gas during photopolymerization. 3) A doping treatment method as a post-treatment, for example, a method of immersing a material to be electrically conductive to which conductivity has been imparted in a dopant solution (for example, an aqueous hydrochloric acid solution) after photopolymerization. As the dopant, any commonly used acceptor dopant can be used. Acceptor dopants include halogens such as chlorine, bromine, and iodine, Lewis acids such as phosphorous pentafluoride and arsenic pentafluoride, protonic acids such as hydrogen fluoride, hydrogen chloride, and sulfuric acid, and transitions such as ferric chloride. Transition metal compounds such as metal chlorides, silver perchlorate, silver boron fluoride, etc., 7,7,
Examples include organic compounds such as 8,8-tetracyanoquinodimethane. In carrying out the present invention, for example, an apparatus as shown in FIG. 1 is used. This device consists of a monomer gas contact tank 1, a monomer gas supply device 2, a dopant supply device 3, and an active energy ray source 4. It is configured to place the processing material 5 thereon. The monomer gas supply device 2 consists of a monomer solution tank 6 and a heating device 7, and the monomer solution (for example, an acetonitrile solution of pyrrole) 8 in the monomer solution tank 6 is
is heated to generate monomer gas (for example, pyrrole gas), which is fed into the monomer gas contact tank 1 through the supply pipe 10 by the nitrogen gas supplied through the nitrogen blowing pipe 9. On the other hand, the dopant supply device 3 is connected to the dopant tank 1.
1 and a heating device 12, the dopant tank 11
The dopant (e.g., iodine) 13 in the interior is heated to generate a dopant gas (e.g., iodine gas), which is passed through the supply pipe 15 by the nitrogen gas supplied through the nitrogen insufflation pipe 14.
The monomer gas is fed into the monomer gas contact tank 1 through the following steps. The monomer gas and dopant gas thus sent into the contact tank 1 come into contact with the surface of the material 5 to be electrically conductively treated and penetrate into the resin of the material 5 to be treated. The material to be electrically conductive 5 is irradiated with active energy rays (for example, ultraviolet light) from an active energy ray source (for example, an ultraviolet lamp) 4 installed above the material to be electrically conductive. The monomer that has penetrated into it is photopolymerized to produce an electronically conjugated polymer (for example, pyrrole is photopolymerized to produce polypyrrole). The generation of this electronically conjugated polymer imparts electrical conductivity to the material 5 to be electrically conductively treated. In addition, since dopants are present as impurities in the resin of the material to be electrically conductively treated, the doping effect improves the electrical conductivity, resulting in greater electrical conductivity. Note that 16 is a discharge pipe for discharging the condensed liquefied monomer and liquefied solvent to the outside of the tank. In this way, a conductive composite in which the electronically conjugated polymer is impregnated into the resin of the material to be electrically conductively treated is obtained, but since the base resin of the material to be electrically conductively treated and the electronically conjugated polymer have a so-called hybrid structure, it is necessary to heat the material, for example. However, the electronically conjugated polymer will not escape from the base resin, and the conductivity will not decrease or disappear due to thermal factors. If the material to be electrically conductively treated is a plastic molded article, a separate device from the above-mentioned device is prepared. Although not particularly shown in this apparatus, the monomer gas contact tank is constructed as a closed container, and a plastic molded article is set in this tank. The means for supplying monomer gas into the closed contact tank may be the same as in the case of the above device, but it is also possible to put a monomer solution at the bottom of the tank and heat it to generate monomer gas in the tank. . Alternatively, the dopant may be placed in a suitable container below the contact tank without contacting the monomer solution. In either case, it is necessary to set the plastic molded article into the contact tank using suitable means so as to bring it into sufficient contact with the monomer gas and the dopant gas. (Function) In the present invention, a monomer capable of forming an electronically conjugated polymer permeates into the resin of the material to be electrically conductively treated,
It is photopolymerized by active energy rays to form a polymer in the resin. Although it is highly unlikely that photopolymerization occurs before the monomer penetrates into the resin and the polymer penetrates into the resin, if such a phenomenon were to occur, the present invention It also includes. (Effects of the Invention) The present invention brings a material to be electrically conductively treated into contact with a gas phase atmosphere of a monomer capable of forming an electronically conjugated polymer,
Since this method involves irradiating active energy rays to cause polymerization, thereby imparting conductivity to the material to be treated, it is easier to produce a conductive composite than conventional methods. Furthermore, since the base resin of the material to be conductively treated and the electronically conjugated polymer impregnated into the resin have a so-called hybrid structure, the conductive composite obtained by the present invention cannot be heated or immersed in chemicals. Conductivity does not decrease or disappear, it has excellent heat resistance and chemical resistance, and in addition, conductivity is not impaired by external force and has extremely high durability as a conductive composite. . According to the present invention, the manufacturing apparatus used for carrying out the invention has a simple structure and the manufacturing cost is low. Moreover, the material to be treated for electrical conductivity is not limited to plastic films or sheets. It can be applied to complex-shaped products such as plastic molded products, long-sized products, and large-sized products, and is effective in producing a wide variety of conductive composites of various types. Furthermore, in the present invention, when a transparent material is used as the material to be electrically conductively treated, its transparency is not impaired, and therefore, it is possible to produce a composite with excellent transparency and electrical conductivity. The conductive composite produced according to the present invention can be usefully used as a material for IC packaging, a material for preventing static electricity damage in IC magazines, etc., and can be used in a wide range of other applications. (Example) Hereinafter, the present invention will be explained in more detail by giving examples. Example 1 50 ml of a methanol solution of pyrrole at a concentration of 0.05 molar is placed in a glass container 1 with an open top, and a small glass container with an open top and high enough to prevent the pyrrole solution from entering is placed in this solution. 0.5 g of iodine was placed in the small container.
A polyvinylidene chloride film with a thickness of 20 μm is placed on the top opening of a glass container, and while heating the inside of the glass container to 40°C, the film is irradiated with ultraviolet rays with a wavelength of around 254 nm from above for 10 hours.
A brown transparent film was obtained. After washing this film with methanol and drying it at 100° C. for 1 hour, its electrical conductivity was measured and it was found to have the desired electrical conductivity.
Furthermore, as a result of measuring the total light transmittance, it was found that the film had desired transparency. These results are the first
Shown in the table. Example 2 Using the apparatus shown in FIG. 1, a nylon-6 film with a thickness of 30 μm was placed on the upper opening of the monomer gas contact tank 1, and an acetonitrile solution of pyrrole at a concentration of 0.5 molar was poured into the monomer solution tank 6. The monomer solution tank was heated to 40°C, and pyrrole gas was supplied into the contact tank 1. Further, iodine was put into the dopant tank 11, heated to 30° C., and iodine gas was supplied into the contact tank 1. A pale yellow transparent film was obtained by irradiating the nylon-6 film with ultraviolet light having a wavelength of around 254 nm for 16.5 hours from above. After this film was subjected to the same post-treatment as in Example 1, its electrical conductivity and total light transmittance were measured, and it was found that it had desired electrical conductivity and transparency. The results are shown in Table 1. Example 3 24 in a 0.01 molar ferric chloride methanol solution
A 300 μm thick soft polyvinyl chloride film soaked for an hour was placed on the top opening of a glass container containing a pyrrole solution similar to that in Example 1, except that iodine was not used as a dopant. A transparent brown film was obtained by heating and irradiating with ultraviolet rays under the same conditions as above. After washing this film with methanol and drying it at room temperature, electrical conductivity and total light transmittance were measured, and it was found to have desired electrical conductivity and transparency. The results are shown in Table 1. Example 4 In a completely sealed container that transmits ultraviolet rays
0.5 molar solution of pyrrole in acetonitrile 50
ml and 0.5 g of iodine in another small glass container, and then set a hard polyvinyl chloride molded product (thickness 500 μm) for automatic IC mounting above the sealed container to prevent it from coming into contact with the pyrrole solution. The inside of the sealed container is heated to 40℃, and the wavelength is
A brown transparent molded product was obtained by irradiating ultraviolet light around 254 nm from the outside of the sealed container for 16.5 hours. After washing this molded article with methanol and drying it at room temperature, its electrical conductivity and total light transmittance were measured, and it was found that it had desired electrical conductivity and transparency. The results are shown in Table 1. Example 5 In a container similar to Example 1, 50 ml of a 0.05 molar solution of thiophene in acetonitrile and 0.5 g of iodine in another small glass container were added.
A polyvinylidene chloride film with a thickness of 20 μm was placed on the top opening of one container, and ultraviolet rays with a wavelength of around 254 nm were irradiated for 10 hours while heating the inside of the container to 40°C to obtain a brown transparent film. Ta. After washing this film with methanol and drying it at 100° C. for 1 hour, its electrical conductivity and total light transmittance were measured, and it was found to have desired electrical conductivity and transparency. The results are shown in Table 1.

[Table] *1: Measured using a high resistance meter.
*2... Measured using a spectrophotometer (light source: tungsten lamp).

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a manufacturing apparatus used for carrying out the present invention. 1... Monomer gas contact tank, 2... Monomer gas supply device, 3... Dopant supply device, 4...
Active energy ray source, 5... Material to be electrically conductive treated.

Claims (1)

[Claims] 1. A conductive material made of plastic is brought into contact with a gas phase atmosphere of a monomer capable of forming an electronically conjugated polymer, and is irradiated with active energy rays to obtain a composite material imparted with conductivity. A method for producing a conductive composite, characterized by: 2. The method for producing a conductive composite according to claim 1, wherein the material to be conductively treated is a plastic film or a plastic molded article. 3. The method for producing a conductive composite according to claim 1, wherein the monomer capable of forming an electronically conjugated polymer is one selected from pyrrole, thiophene, furan, indole, and derivatives thereof.