JPS59218842A - Conductive high molecular shape and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductive polymer molded article, and an object thereof is to provide a conductive polymer molded article in which at least one surface is highly conductive and the other surface is highly insulating. shall be.

Conventionally, many methods have been proposed for imparting conductivity to electrically insulating plastics, but each method has the following drawbacks. For example, methods in which a conductive layer is formed by gluing a metal or other conductive sheet onto the surface of a plastic molded product, or by applying a conductive paint, etc., are complicated to operate and are difficult to obtain. The mechanical and physical strength of the conductive layer of the product is poor, and the conductive layer is easily peeled off or damaged by external or internal impact. In addition, with the method of mechanically dispersing metal powder or conductive carbon black in plastic and molding it, it is generally impossible to impart high conductivity. When the amount of added material is increased, various physical properties of the resulting molded product deteriorate, resulting in a loss of practicality.

As a result of intensive research in order to solve the above-mentioned drawbacks of the prior art, the present inventor has found that by incorporating conductive inorganic particles in a specific state into a polymer material, a method that cannot be obtained with conventional conductive plastic molded products.・We have succeeded in obtaining a conductive polymer molded product that has extremely high conductivity and has no problems with various physical properties, thereby completing the present invention.

That is, the present invention provides a molded article comprising a polymer material matrix and conductive inorganic particles included in the matrix, wherein the inorganic particles are densely aggregated in the direction of at least one surface of the molded article and are conductive. The present invention provides a conductive polymer molded article characterized by forming a conductive layer, and a method for producing the same.

Next, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of the molded product of the present invention in the form of a sheet, where reference numeral 1 indicates the sheet-like molded product, 2 indicates the polymer material matrix, and 3 indicates the conductive material. 4 represents an insulating layer, and 5 represents a conductive layer. As illustrated in FIG. 1, the molded product of the present invention includes at least one conductive inorganic particle 3 in an integrally molded polymer material matrix 2.
It is characterized by the presence of an insulating layer 4 that is densely aggregated in two plane directions to form a conductive layer 5 and substantially free of conductive particles. By adopting such a configuration, the molded article 1 can maintain various physical and mechanical properties that are almost the same as those of a molded article that does not contain conductive particles, and the conductive layer can maintain properties that cannot be achieved with conventional techniques. Moreover, since the conductive layer is integrated with the polymer material matrix, unlike conventional conductive paints, which have the disadvantages of particle drop-off and layer peeling. The drawbacks as in the prior art are completely solved.

Next, various materials used in the present invention will be explained. The polymer materials used in the present invention include polyethylene, polypropylene, polystyrene, polyvinyl chloride, fluorinated polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, and polyvinylidene acetate. , polybutadiene, A
B S resin, As resin, polyvinyl acetal, polyurethane, polyamide, polyethylene terephthalate, polyethylene terephthalate, polyether sulfone, polysulfon, polycarbonate, polyphenylene oxide, phenol resin, silicone resin, epoxy resin, melamine resin, urea resin, etc. Any of the polymer materials conventionally used in various plastic molded products can be used. When producing the molded article of the present invention, the above-mentioned polymeric materials are used in the form of a liquid by heating and/or using an appropriate solvent, or a polymer precursor (prevo+)-r-% oligomer, They are used in the form of monomers, etc.) and, after necessary treatments, are solidified or hardened by cooling, evaporation of solvents, polymerization initiators, curing agents, crosslinking agents, heating, energy supply, etc. to form molded products.

The conductive inorganic particles used in the present invention include the periodic table II islands, ■-1■a, ■, Ib, Ilb, l[b, ■b
particles of conductive compounds or alloys such as elements of the group elements or their oxides, sulfides, etc., carbon black, graphite, etc. Specifically, Zn, AI, Co,
Au, Sn%Ag, Ni5Fe, W, Mo,
Be, Ti, etc. particles, oxides and sulfides include Z
n O, F e 203, ■n203, SnO□, C
oo, NiOlNlol, Cu2O, v205, PbS
Examples of ZnS particles and alloys include particles of stainless steel, bronze, brass, etc., particles of conductive carbon, and graphite. The above-mentioned conductive particles preferably have an average particle size in the range of about 0.01 micron to about 1,000 microns, and some of the above-mentioned metal particles have an oxidation film or anti-oxidation treatment. Therefore, before use, it may be necessary to perform a cleaning treatment using a solvent cleaning method, a chemical method (for example, a pickling method, an alkali washing method, etc.).

Next, to explain the method for manufacturing a molded article of the present invention, first,
It is necessary to liquefy the polymer material by some means. Methods for such liquefaction include melting by heating, solution using an appropriate solvent, use of a polymeric material, or a combination thereof, and any method may be used.

Next, the required amount of the conductive inorganic particles is added to the liquid polymer material, and a dispersion liquid is prepared by uniformly dispersing the conductive inorganic particles in the system using any known dispersion means. do. After the obtained dispersion is injected into the desired mold or coated on a substrate such as release paper, the conductive inorganic particles in the dispersion are collected in the direction of at least one surface of the molded object by the magnetic force of the dispersion. let

The methods for aggregating the above particles include (method using the difference in specific gravity between liquid polymer material and conductive inorganic particles; and (2)
There are methods that use magnetic force, etc., but the former method involves leaving the conductive inorganic particles standing still and using gravity to gather them densely in the downward direction, and using centrifugal force to gather the particles densely in any surface direction. There is a way to collect them. The latter method can be used when the conductive inorganic particles are magnetic, and the particles can be densely aggregated in any plane direction of the molded article. The method using gravity is useful for plate-shaped molded products such as plate, grate, sheet, or film, and the method using centrifugal force is useful for other molded products. When using magnetic force, it is useful when manufacturing molded products continuously.

After assembling the conductive inorganic particles in at least one plane direction, the liquid polymer material containing the particles is subjected to cooling, evaporation of a solvent, heating, irradiation with energy rays, or other solidification or curing means. A molded article is obtained.

In the above method, the ratio of the polymer material to the conductive inorganic particles varies depending on the intended use and shape of the molded product, but generally the former/the latter = 9515
It is used in a weight ratio of ~10/90. For example, for thin films or sheets, a relatively large amount of inorganic particles (e.g. 40/40 to 20/80) is used, and for thick films or sheets, a relatively small amount of inorganic particles (e.g. 80/20) is used. ~
40/60) is preferably used. Also, when using a relatively large amount of conductive inorganic particles (for example, 20/8
0 to 10/90), the molded product of the present invention can also be obtained by the method of another embodiment. This embodiment:
It is useful for producing plate-like molded products such as sheets, films, and plates, and is carried out as follows: In other words, a dispersion containing a relatively large amount of inorganic particles is injected into a mold or a substrate such as release paper is used. The inorganic particles are aggregated in one surface direction as described above, and then the sheet-like dispersion is incompletely assimilated or hardened, and before the surface is completely hardened, the conductive inorganic particles prepared separately are The molded article of the present invention can be obtained by applying a liquid polymeric material containing no particles and then solidifying or curing the entire body as described above.

The essential components of the present invention are as described above, but various known additives, such as colorants, may be used as components of the molded product, as long as they do not impair the conductivity or physical and mechanical properties of the resulting molded product. , a plasticizer, etc. can be incorporated as necessary. In particular, in the conventional kneading method, conductive inorganic particles are present throughout the molded product, so it is difficult to color the molded product to a hue other than that of the inorganic particles. Since there is a layer substantially free of particles, this part has the advantage that it can be colored as desired.

In terms of the manufacturing method, the conductive layer of the molded product obtained as described above has a higher level of conductivity than the molded product produced by the conventional cross-wire method.
Excellent conductivity (e.g. 1oL-to'!Ω・Crr
L), but by subjecting the molded product to a specific treatment after forming, its conductivity can be dramatically improved (for example,
It was found that the physical properties of the molded product were also enhanced. Such a treatment method is a method of pressurizing the conductive layer of the obtained molded product at room temperature or under heating. It is thought that the above-mentioned effects are obtained because such pressure treatment further strengthens the contact between the inorganic particles in the conductive layer. The pressurizing conditions are a pressure of about 5 Kg/lyA to 200 Kg7'r, rl at a temperature of about 5°C to about 300°C, preferably 50-150°C. By such pressure treatment, the conductive inorganic particles in the conductive layer are densified to about 80-95% by weight. Note that such pressure treatment may be performed after the molded product has solidified or hardened, or may be performed simultaneously with the solidification or hardening of the molded product. Particularly when using a precursor of a polymeric material, it is desirable to carry out pressure treatment before curing is completed.

The conductive polymer molded product of the present invention obtained as described above has a significantly higher conductivity of the conductive layer than conventional conductive polymer molded products (those provided with a conductive layer). Moreover, the physical and mechanical strength of the conductive layer is extremely excellent, and problems such as the conductive material falling off, layer peeling, and damage do not occur even when subjected to internal and external shocks. In addition, when compared with conventional molded products made by kneading, the electrical conductivity is much superior, and the physical and mechanical strength is also much superior. Therefore, the conductive polymer molded product of the present invention can be used as a conductive sheet, an electrocalyx, a printed circuit, an electromagnetic wave shielding body such as an IC, a sheet heating element, a resistor, a sheet photoconductive conversion element, a sheet capacitor, It is useful as a material for electrophotographic charging, as a stopper material, and for various other purposes.

Next, the present invention will be specifically explained with reference to Examples. References in the middle of the text and in the text are based on weight.

Example 1 70 parts of methacrylic resin (Dianal RB-801, Mitsubishi Rayon) was dissolved in 280 parts of tetrahydrofuran, 30 parts of sperm-treated tin powder of 200 mesh was added thereto, and the mixture was uniformly dispersed with a homomixer. CrfL
Pour into a flat mold of 5 mm x 30 CrrL,
When the sample is exposed to Pi'II for 10 minutes, the tin powder is uniformly and completely precipitated in the lower layer, and no tin powder is observed in the upper layer. Thereafter, by spontaneously emitting a solvent from the flat mold, the acrylic resin layer (insulating layer) that does not contain tin powder and the layer (conductive layer) in which tin powder is densely aggregated in the resin are integrated. A sheet-like conductive polymer molded product (1-A) was obtained. The total thickness of the molded product is approximately 0.8
mw, the thickness of the conductive layer was about 0.2 cm, and the tin powder in the conductive layer was 60 cm. Next, this molded product was heated to 14
A sheet-like conductive polymer molded product (r-B) of the present invention was obtained by pressure treatment at a temperature of 0° C. and a pressure of 70 KgA4.

Example 2 60 parts of polyvinyl chloride (Zeon 135J, Nippon Zeon) was dissolved in 340 parts of tetrahydrofuran, 40 parts of nickel powder with a particle size of about 5 microns was added thereto, and the present invention was prepared in the same manner as in Example 1. A sheet-like conductive polymer molded product (2-h) was obtained. This molded product was heated at a temperature of 130°C and
A sheet-like conductive polymer molded article (2-B) of the present invention was obtained by pressure treatment at a pressure of Ky/lri.

Example 3 Polysulfone (Udel Polysulfone, 8 San Kagaku) 5
0 parts of graphite powder (KS75,
50 parts of Lonza) were added, uniformly dispersed with a homomixer, and then placed on a glass plate at approximately 200 to 300 f/rr? It was applied at a ratio of 100 ml and left to stand for about 20 minutes. After the graphite powder has precipitated downward, a solution of polysulfone in N-methylpyrrolidone (solid content: about 20 parts) containing no conductive powder is added at a concentration of about 300 to 400%, taking care not to mix it with the already applied layer.
f/n? The film-like conductive polymer molded product (3-A) of the present invention is obtained by coating the film at a ratio of Wait. Next, the molding! /I was subjected to pressure treatment under the conditions of 15 Kg/- and 50 Kg/- to obtain a film-like conductive polymer molded product (a-B) of the present invention.

Example 4 Polypropylene glycol (hydroxyl value SS, O), 40 parts of urethane prepolymer (NCO==6.0%) obtained from tolylene diisocyanate, and amine curing agent (
Add 40 parts of cleaned 100 mesh copper powder to the mixture with 20 parts of MC-591 (Mitsui Nikkan Urethane),
Disperse it evenly with a homomixer and pour it into a mold of a certain shape. If it is left as it is for one day, all the copper powder will precipitate uniformly in the lower part, and no copper powder will be observed in the upper part. After that, before the molded product is completely cured, the molded product is taken out from the mold and subjected to pressure treatment at 100° C. and 80 V4/crl to obtain the plate-shaped conductive polymer molded product (4-B) of the present invention. Obtained.

Example 5 40 parts of cleaned brass powder of 150 mesh was added to a mixture of 50 parts of epoxy resin (Epicote 828, Shell Petroleum), 4 parts of diethylenetriamine, and 0.05 part of tridimethylaminomethylbenzene, and the mixture was homogenized using a homomixer. The mixture is mixed and dispersed and poured into a mold of a certain shape.

Leave it as it is for 1 hour to completely precipitate the brass powder in the lower layer. Before the molded product was completely cured, the molded product was taken out from the mold and subjected to pressure treatment at 80° C. and 50 ~/crA to obtain a plate-shaped conductive polymer molded product (s-B) of the present invention. .

Example 6 Polyvinyl chloride (Zeon 135 J, Nippon Zeon) 60
75 micron graphite powder (KS75, Lonza) was dissolved in 340 parts of tetrahydrofuran.
40 parts were added and uniformly dispersed using a homomixer to obtain a dispersion. This dispersion was poured into a flat mold capable of applying centrifugal force, centrifuged at a rotation speed of 700 rpm for 5 minutes, and then the solvent was evaporated to form a curved sheet-like conductive polymer mold of the present invention (6- A) was obtained. The molded product was heated to 120
A curved sheet-like conductive polymer molded product (a-B) of the present invention was obtained by pressure treatment under the conditions of 50 Kq/cdl and 50 Kq/cdl.

Example 7 Polysulfone (U5-delpolysulfone, Nichido Kagaku) 6
0 part was dissolved in 240 parts of N-methylpyrrolidone, 40 parts of cleaned tin powder of 100 mesh was added thereto, and the mixture was dispersed in a homomixer to give a dispersion liquid.

The dispersion was poured into a flat mold, centrifuged at 400 rpm for 5 minutes, immersed in water to solidify the molded product, further washed in warm water at 50°C, and dried to form the molded product. I got it. Next, the molded product was subjected to pressure treatment at 150°C and 70°C to produce the sheet-like conductive polymer molded product of the present invention (7-
B) was obtained.

Example 8 Polypropylene glycol (hydroxyl value 55.0) and 4,
Urethane prepolymer obtained from 4-diphenylmethane diisocyanate (viscosity 78P/25°C, NGO
6.0) 40 parts, amine curing agent (MC-591,
20 parts of Mitsui Nisso Urethane) and 40 parts of 5 micron nickel powder were uniformly mixed and dispersed using a homomixer, poured into a flat mold, centrifuged at 500 rpm for 5 minutes,
After that, it was cured at 110℃ for 3 hours, and then heated to 100℃ for 5 hours.
The sheet-like conductive polymer molded product (8-B) of the present invention was obtained by pressure treatment under the condition of 0 Ky/ad.

Example 9 Sheet-like conductive material of the present invention was subjected to pressure treatment in the same manner as in Example 1, except that instead of the precipitation in Example 2, nickel powder was forcibly precipitated using a permanent magnet. A polymer molded product (9-B) was obtained.

Example 10 (Measurement of N receptivity, etc.) The properties of the conductive polymer molded products of the present invention obtained by 44J in Examples 1 to 9 were as shown in Table 1 below.

The electrical properties were measured under the conditions of a temperature of 24° C. and a relative humidity of 60% based on the Japan Rubber Institute standard (SRIS2301).

1-A O,80,2604X10510151-B
O,40,1902,5X10 10152-A
1.2 0.4 60 2.5X10
10”2-B O,70,2905,0X10 1
03-A 2.0 0.5 70 6.2
X10 10153-13 1.2 0.3
90 3.2X10 104-B
5.0 1.0 B5 3. lX1O
-510j15-B 4.0 1.0
90 7.2X10 106-A 1.0
0.2 70 41X10 10”6-
B O,60,1902,0X10 107-
B 1.0 0.1 90 1
．． 4X10 108-B 1.0 0.2
'! 0 3. lX10 109-
B O,60,1907,8 Oshi, guide again? No damage or peeling occurred due to impact inside or outside the Fj layer.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a molded product according to an embodiment of the present invention.
1 is a molded article, 2 is a polymer material matrix, 3 is a conductive inorganic particle, 4 is an insulating layer, and 5 is a conductive layer.

Claims (1)

[Scope of Claims] (1) A molded article comprising a polymer material matrix and conductive inorganic particles contained in the matrix,
A conductive polymer molded article, characterized in that the inorganic particles are densely aggregated in the direction of at least one surface of the molded article to form a conductive layer. (2) Conductive inorganic particles range from about o, oB to about i, oo
Claim No. (1) having an average particle size of o microns.
The molded article described in section. (3) The molded product according to claim (1), which has a planar shape such as a plate, sheet, or film. (4) The conductive layer is a conductive inorganic material containing about 60 to 95% by weight. ◇ (5) The molded article according to claim 1, wherein the conductive layer contains about 80 to 95% by weight of conductive inorganic particles. ). (6) The molded article according to claim (1), wherein the conductive layer has a specific resistance value of about 10 to 10 Ω·α.
) After mixing and uniformly dispersing conductive inorganic particles in a liquid polymeric material, a liquid polymer-forming precursor capable of forming a polymeric material, or a mixture thereof, the inorganic particles are mixed with at least one 1. A method for producing a conductive polymer molded article, which comprises assembling the mixture in two plane directions, and then assimilating or hardening the mixture. (8) The manufacturing method according to claim (7), in which the inorganic particles are aggregated by utilizing the difference in specific gravity between the polymeric material and the conductive inorganic particles. (9) The manufacturing method according to claim (7), wherein the liquid polymeric material is a solution of a polymeric material in an organic solvent. Claim No. 1 characterized in (
The manufacturing method according to any one of items 7) to (9).