JPS59189171A - Electrically conductive resin composition - Google Patents

Abstract

PURPOSE:To provide an electrically conductive resin compsn. which can be colored with an arbitrary hue without detriment to the hue and transparency inherent to resin, by blending fine silicic acid powder, a polyethylene oxide compd., etc. with a synthetic resin. CONSTITUTION:93-40wt% synthetic resin such as polyethylene or an ethylene/ vinyl acetate copolymer, 5-40wt% fine silicic acid (salt) powder having a specific surface area of 10-400m<2>/g, and 2-20wt% at least one member selected from among a polyethylene oxide compd. (e.g. polyethylene glycol), a polypropylene oxide compd. (e.g. polypropylene glycol) and an org. electrolyte in the form of a salt (e.g. potassium acetate or sodium alkylbenzenesulfonate), are kneaded together in a Henshel mixer or an extruder to obtain a resin compsn. having a volume resistance of 10<13>OMEGAcm or below.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductive resin composition having a colorable color tone.

Conventionally, adding carbon black or metal powder to plastics has been done to make them conductive, but this method loses the original color tone of the plastics, and also causes the loss of transparency in transparent plastics. There are other problems.

On the other hand, as a method of imparting conductivity to plastic without impairing its original color tone or transparency, there is a method of coating or adding an antistatic agent to plastic. However, it is difficult to impart volume conductivity.

In view of the current situation, the inventors of the present invention have conducted various studies in order to impart volume conductivity without significantly impairing the original color tone of plastics, and as a result, they have incorporated specific particulate silicic acid or silicates and specific compounds into synthetic resins. It was discovered that by doing so, a resin composition having volume conductivity and a color tone that can be colored can be obtained, and the present invention was achieved.

That is, (4) Synthetic resin (sometimes referred to as components below C) 93~
40% by weight, (to) 10-40 On? Particulate silicic acid or silicate having a specific surface area of 2 to 20% by weight) and has a volume resistivity of 1018 Ωm or less.

The characteristics of the present invention are that components that cannot obtain satisfactory volume conductivity even if they are blended alone in a synthetic resin, and conductivity with a volume resistivity of 1013 Ω or less can be obtained by blending 0 components together. It is in a place where it can be done. Moreover, the ingredients (b)
, component (q) is colorless to light in color, the resulting composition has a colorable color.

The present invention is completely different from the method of adding conductive fillers such as carboxylic acid salts, metal powders, etc. in that it does not significantly impair the color tone, and it also has various characteristics in that it provides volume conductivity. This is clearly distinguished from the proposed method of imparting surface conductivity by coating or kneading an antistatic agent.

The present invention will be explained in detail below.

The synthetic resin used in the present invention is not particularly limited, but examples include polyethylene, EvA resin, polypropylene, polystyrene, ABS resin, As resin, methacrylic resin,
Polyamide, polycarbonate 1, polyester resin,
Examples include vinyl chloride resin, epoxy resin, and phenol resin.

The fine particle silicic acid or silicate used in the present invention may be produced by any method such as a dry method or a wet method, but
Its specific surface area is 10-400? /9 is required. The specific surface area is 10? /y, specific surface area is 400 tt? If the value exceeds /f, satisfactory volume conductivity cannot be obtained.

Examples of polyethylene oxide compounds and polypropylene oxide compounds used in the present invention include polyethylene glycol, polypropylene glycol, polyoxyethylene-polyoxypropylene block copolymer, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, and polyethylene glycol. Examples of organic electrolytes with a salt structure include potassium acetate,
Carboxylic acid salts such as thorium laurate, sulfate ester salts such as sodium alkyl sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium alkyl sulfonate, sodium alkylbenzene sulfonate, alkylnaphthalene) Li, sodium phonate, dialkyl sulfosuccinate Sulfonates such as sodium acid esters, sodium alkyl phosphates, phosphate ester salts such as sodium polyoxyethylene algyl ether phosphates, tertiary amine salts,
Examples include amine salts such as quaternary ammonium salts. Moreover, these compounds can be used in combination as necessary.

The blending ratio of component σ in the present invention is 5 to 40% by weight, and the blending ratio of component 0 is 2 to 20% by weight. In addition, it is preferable that the blending ratio of the ingredients is ≦2/3. If component (b) is less than 5% by weight, satisfactory volumetric conductivity cannot be obtained, and if it exceeds 40% by weight, the processability and mechanical properties of the composition are greatly reduced, causing various problems. . Also, the blending ratio of component 0 and component (b) is qo>
If it is 2/3, component 0 tends to precipitate onto the surface of the composition, which is not preferable.

Any suitable mixing or kneading method can be used to blend component (provided) and component 0 into the synthetic resin, examples include Henschel mixer, kneader, extrusion fi, Bamba IJ-j mixer, roll method, etc. can be given.

Methods for adding and blending component 0 include ■ Adding it alone;
There are two methods: ■ Adding it as a solution, ■ Adding it by pre-adhering it to component Q\), Q3), (q
It can be appropriately selected depending on the properties of each component.

The composition of the present invention may contain additives such as antioxidants, ultraviolet absorbers, colorants, etc., if necessary.

Various molding methods such as extrusion molding, injection molding, and press molding can be applied to the composition of the present invention.

The present invention will be explained below with reference to Examples, but these are merely illustrative and the present invention is not limited thereto.

The volume resistivity values in Examples were measured at 23° C. and 50% RH using a super insulation meter (SMIQ-E manufactured by Toa Denpa Kogyo).

Examples 1 to 4 Comparative Examples 1 to 4 EVA resin (M 18 f//10 minutes, N1 content 1
(5% by weight), fine particles of silicic acid having different specific surface areas, and polyethylene glycol (molecular weight: 200) were kneaded and blended at a predetermined blending ratio in a small kneader at a resin temperature of 160''C to prepare a press sheet with a thickness of 0.2cm. Table 1 shows the physical properties of the obtained pressed meat.

The press meat obtained from Examples 1 to 4 in Table 1 was 1018Ω.
It had a volume resistivity value of cm or less, and was colorless and transparent.

80% by weight with a specific surface area of 240%, 15% of fine particle silicic acid with rz/y and 5% of various compounds as component 0.
were mixed in a small kneader at a resin temperature of 160'C to produce a press sheet with a thickness of 0.2 layers. Table 2 shows the physical properties of the obtained press sheet.

Table 2 □ Lowering 1 "1 The press sheets obtained in Examples 5 to 11 had volume resistivity values below '0', were colorless and transparent.

Example EvA&t finger (MI a &/10 min, VA content 15% by weight) 80% specific surface area 200,? /f particulate silicic acid 15% by weight and polyJ ethylene glycol (molecule i40'o) 4.5% by weight, potassium acetate 0
．． 5% by weight (here, potassium acetate was an aqueous solution of 65Ni% and mixed with polyethylene glycol) was blended in a small kneader at a resin temperature of 160°C, and a press sheet with a thickness of 0.2 mr was made. Created. The obtained press sheet had a volume resistivity value of 8 x 1 om, and was colorless and transparent.

Example 13 EVA resin (M I 3 f/10 min, VA content 15
Weight%) 65% by weight and specific surface area 20On? /p 30% by weight of fine-grained silicic acid and 5% by weight of trimethylhydroxyethylammonium chloride (trimethylhydroxyethylammonium chloride was made into an aqueous solution, mixed with fine-grained silicic acid, and dried) were mixed into a resin using a small kneader. Kneaded and blended at a temperature of 160'C, with a thickness of 0.2v
A press sheet for an was created.

The obtained press sheet had a volume resistivity value of 5xio Ωtwr or less, and was colorless and transparent.

Example 14 Low density polyethylene (M I 1.59710 min, density 0.922 f/c1d) 80 If amount % specific surface area 240rr? A press sheet containing 15% by weight of fine particle silicic acid and a thickness of about 0.2 mm was prepared.

The obtained press sheet is 8 X L O” 0cm
It had a volume resistivity value of less than 100 g, and was colorless and transparent.

Example 15 Polypropylene (M 169/10 min, Lancum copolymer with ethylene content of 4% by weight) 78% by weight with a specific surface area of 200, ? 20% by weight of particulate silicic acid /g and 7% by weight of polyethylene glycol (molecular weight 200) were mixed together with an antioxidant in a Henschel mixer, and then kneaded and granulated in a twin-screw extruder at a resin temperature of 220°C.

Obtained7. Itsu, 2. Thick. , rpupu, Yuuto. The obtained press sheet had a volume resistivity of 2×10 9 Ω, and was colorless and transparent.

Example 16 A press sheet obtained by replacing the polyethylene glycol in Example 15 with sodium dotecylbensene sulfonate had a volume resistivity value of 8xlo, flC* or less, and was colorless and transparent.

Example 17 Using the pellets obtained in Example 5, injection molding (
A molded product with a thickness of 1.5 mm was obtained at a set temperature of 200°C. The obtained molded article had a volume resistivity value of 4×10 9 Ωf, was colorless, and had transparency.

%) 80 Shigesato% and specific surface area 240? 15% by weight of finely divided silicic acid and polyethylene glycol (molecular weight 2
00) 5% by weight in a Pan Bali mixer at a resin temperature of 150
After cross-mixing with 'C and pelletizing, inflation molding (set temperature 160°C) was performed to a thickness of 0.1. ro
A film of m was obtained. The resulting film was 5×1.
It had a volume resistivity value of 09Ω, and was colorless and transparent.

Claims (1)

[Claims] (A) Synthetic resin 98-40% by weight, ■) 10-400 rr? 5 to 40% by weight of fine particle silicic acid or silicate having a specific surface area of A conductive resin composition comprising 2 to 20% by weight of a compound and having a volume resistivity of 100 units or less.