JPS608335A - Electrically conductive resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent electrical conductivity, with little lowering in mechanical strength and increase in viscosity, by compounding a thermoplastic resin with a specific carbon black. CONSTITUTION:100pts.wt. of a thermoplastic resin is compounded with preferably 4-20pts.wt. of an electrically conductive carbon black having a DBP absorption of >=400ml/100g, preferably 400-600ml/100g and a heavy metal content of <=500ppm, preferably iron content of <=250ppm, vanadium content of <=100ppm and nickel content of <=50ppm.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an improvement in a conductive composition comprising a thermoplastic resin mixed with carbon black.

[Prior Art] Conventionally, conductive resin compositions in which carbon black is blended with a thermoplastic resin are known. In this case, as carbon black, acetylene black, thermal black, furnace black, etc. are usually used, and the resin composition does not show conductivity depending on the amount added, but 9,
In order to obtain a highly conductive composition, it is necessary to incorporate it in a fairly large amount.

Therefore, when trying to obtain a highly conductive resin composition using conventional carbon black, there is a drawback that the excellent f=fH characteristics of 431 resin are lost. That is, with conventional carbon black, desired conductivity can be obtained by blending multiple components, but the resulting resin composition has a decrease in mechanical strength, a marked increase in viscosity, and poor melt fluidity. It has the drawbacks of low deformation, extremely poor extrusion and injection molding processing, and extremely poor practicality. On the other hand, Ketjenblack EC (manufactured by Lion Akzo Corporation) is known as a highly conductive carbon black, and a resin composition containing this material provides high conductivity. It has the disadvantage of poor dispersibility.

〔the purpose〕

The present invention provides a conductive resin composition that is highly conductive, has little decrease in the mechanical strength of the resin, and is easy to process by extrusion or injection molding, unlike conventional resins containing carbon black. This is the 1st target.

〔composition〕

That is, according to the present invention, in a composition in which carbon black is blended with a thermoplastic resin, the carbon black has a DBP oil absorption of 400 m Q / 100 g or more.
There is provided a conductive resin composition characterized by using conductive carbon black having a heavy metal content of 500 ppm or less.

In the present invention, as carbon black, 1)+3
11 is characterized by using conductive carbon black with an oil-absorbing claw of 400 m Q / 100 g or more and a heavy metal content of 500 P P B or less, but when such carbon black is embedded in a resin, its Provides the composition with higher electrical conductivity than regular carbon black.

In the carbon black used in the present invention, (7)
The oil absorption amount is /I00 IT+ Q, /10
However, if the oil absorption amount is smaller than this, a large amount must be added in order to obtain a highly conductive resin composition, and the properties of the resin tend to be impaired accordingly. In the carbon black used in the present invention, l1n
There is no particular restriction on the upper limit of the DBP oil absorption amount, but from the viewpoint of ease of production, an appropriate value is 700 ml/1.00 g or less, and in the case of the present invention, the DBP oil absorption amount is particularly , preferably in the range of 400 to 600 mQ/100 g. In the carbon black used in the present invention, the heavy metal content is maintained at 500 ppm or less in relation to the above-mentioned 1) regulation of BP oil absorption. In this case, heavy metals include iron, vanadium, manganese, nickel, chromium, copper, cobalt, etc. In the case of the present invention,
Is the total amount of heavy metals less than 500 ppm? I
Preferably, iron content is 250 ppm or less, vanadium content is 110 ppm or less.
The nickel content is specified to be 0 ppm or less, and the nickel content to be 50 ppm or less. If the heavy metal content in carbon black exceeds 500 ppm, the resin will be affected by the heavy metal ions, and the carbon black's strength will decrease when carbon black is added to the resin.
The F2 properties of the molded door of the resin composition deteriorate significantly.

In addition, the DBP oil absorption amount referred to in this specification is A S 1'
MI means the oil absorption amount specified in IJ2414-79.

The bar used in the present invention! i There are various conventionally known plastic resins, and there are no particular restrictions, but specific examples include low, medium and high density polystyrene, cotton-like low density polyethylene, polypropylene 1-non, and ethylene-propylene copolymer. combination, ethylene-it; acid-vinyl copolymer,
Ethyl 1-non-acrylic acid ester copolymer, acryloni-1 heli-rubutadiene-1-non quinary copolymer, polystyrene, acrylonitrile-styrene copolymer, di(
・Ryl rubber, butadiene rubber, styrene-butadiene rubber, ethylene-brobylene-diene rubber, silicone rubber, thermo-rif plastic polyurethane resin, polyamide resin, polyester resin, polycarbonate, polyvinyl chloride,
Examples include polyacetal resin.

In the present invention, the carbon black self-sharpening claw for resin varies depending on the type of resin used and the purpose of use, but
(If there is too little at the edge, the effect of imparting conductivity will be small; if it is too much, the effect of adding it will be saturated, and it will be difficult to incorporate it evenly into the resin. 1. Generally, it is preferable to use 2 to 30 parts by weight or 4 to 20 parts by weight.In addition, the composition of the present invention may contain antioxidants commonly used in thermoplastic resins. Auxiliary agents such as stabilizers, lubricants, and flame retardants can be used as appropriate for π.

In order to blend carbon black into thermoplastic resin,
It can be carried out by a conventional method, for example, a method using a batch-type mixing machine such as Panbury Mixer or Intermix.

〔effect〕

In the present invention, a highly conductive resin composition can be obtained with a small amount of carbon black, so unlike conventional conductive resin compositions, its mechanical strength and moldability are excellent. ing. Therefore, the conductive resin composition of the present invention can be applied to various uses, such as high voltage cables, ignition cords, surface heating elements,
In addition to conductive materials such as masks, packaging materials for electronic devices and ICs that need to avoid electromagnetic interference, and even bidets.
It can be used in many fields, such as application to fA desk molding materials, permanent antistatic materials, etc.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples. The unit "r%" used in the examples represents weight %.

Volume resistivity is 4'8SRIS 230 according to Japan Rubber Association regulations.
According to 1, Izot WIt impact strength is JIS K-71
It was defined by the method described in 10.

In addition, the carbon black fil used in the examples
Class i and properties are shown in Table 1. In Table 1, C is a comparative product (manufactured by Lion Akzo, trade name: Ketjen Black I).
EC).

Table 1 Example 1 Various thermoplastic resins and the carbon black listed in Table 1 were added to the specified amounts, and an antioxidant (manufactured by Ziba Geigy, trade name Irganox 1010) was used at 1.0'JI! , and 0.5% of lubricant (Lion Akzo M1. trade name Armowax BiBS Powder) were kneaded in a show intermix (type 1 made by Tatsutaura), and then milled in an 8-inch two-wood roll mill (four-phase I machine). EQ) and a square pelletizer (manufactured by Horai Tekkosho, GIIP type) to make pellets.

150 to this pellet 1 at a pressure of 1501 tg/cm2
X 250
Mata + t, injection molding L% (84M Fl fat industry,
TS 150 type) 80 x 70 x 3mm1
'i flat plate (B), and its volume resistivity was measured.

The results are shown in Table 2.

Table 2 (1) Table 2 (II) (Note) Explanation of symbols for thermoplastic resins 110PE: High-density polyethylene (manufactured by Layered Chemical Co., Ltd., trade name Santic 5360) LDPE: Low-density polyethylene (manufactured by Mitsubishi Yuka Co., Ltd., product name Santic 5360) (Product name: Yucalon ZF-30) EVA... Ethylene-n-vinyl trichloride copolymer (manufactured by Mitsubishi Yuka, trade name: Yucalon IEVA 5011) ABS...
・ABS wood 1m (Mitsubishi Monken I, manufactured by Kasei, product name Toughflex N-710) Nylon...Nylon 66 (DuPont surplus, product name Li1
Itel 5T801) Example 2 Polyvinyl chloride (manufactured by Zeon, trade name P2]n1)
O-3FP) 50.5%, plasticizer (Oihe Kagaku!!1),
Product name 1' (+ 1' II) 40%, carbon black 874 listed in Table 1, stability rule 1. (3% and lubricant 0.5% were pelletized in the same manner as in Example 1, and then a flat plate of 80 x 70 x 3 WIIW thickness was made by injection molding, and its volume resistivity was measured. The results are shown in Table 3. show.

Table 3 Example 3 AIIS (Mitsubishi Moresan 1~Kasei Co., Ltd., Tufflex N-
710) and the carbon black listed in Table 1, the relationship between volume resistivity and Izod 1 to impact strength was measured. The results are shown in Table 4.

No. 4 U1 Example 4 Pellets 1 to 1 were prepared in the same manner as in Example 1, with the blending ratio of 110PE (manufactured by Asahi Kasei, Santic S-360) and the carbon black described in No. 11) being the same as in Example 1. Pellet 1-temperature 245℃, 1.10 wa/cm
The sample was injected into a spiral mold that was kept at 55° C. for 12 seconds at a pressure of 1, and the length of the material penetrated into the mold was measured. At the same time, the volume resistivity was measured to determine the relationship between the two.

The results are shown in Table 5.

From the results shown in Table 5 and above, in the case of the present invention, a resin composition with high conductivity, good mechanical strength and moldability can be obtained with a reduced carbon black content.

Patent applicant Lion Akzo Co., Ltd. Representative Patent Attorney
Toshiaki Ikeura

Claims (1)

[Claims] (1) In the eleventh composition in which carbon black is blended with ifi plastic resin, as the carbon black, 1
) A conductive resin composition characterized by using conductive carbon black having a 1111 oil absorption of 400 mO,/100 g or more and a heavy metal content of 500 ppm or less.