JPH0341371Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This invention relates to a conductive thin film that has excellent properties such as chemical resistance, water resistance, and flexibility. In recent years, there have been very strict requirements for various properties of power cables, and it is natural that the conductive thin film used for forming semiconductive layers in such power cables must have waterproof, moisture-proof, chemical-resistant, and flexible properties. Extremely high characteristics such as flexibility and adhesiveness are required. However, in general, (i) when blending conductive carbon into a thermoflexible resin to obtain a conductive composition, in order to obtain a conductivity of 10 ⁰ to ^{10 4} Ω-cm, the carbon content must be increased by increasing the amount of carbon in the resin.
A large amount of carbon must be blended, 40 to 150 parts by weight per 100 parts by weight, and it is very difficult to make a resin composition into a film or sheet with such a large amount of carbon mixed in. Even if it could be processed, its mechanical properties such as tensile strength, low-temperature brittleness, and flexibility would be significantly reduced. (ii) Thermoflex resins inherently have excellent water-blocking properties and chemical resistance. However, under harsh usage conditions such as contact with special chemicals, its functionality deteriorates significantly over a long period of time. There are many laminates,
Since the two materials originally have different physical and chemical properties, the adhesive force between them is weak, and it is difficult to obtain a laminate that can exhibit sufficient functionality. Even if the two could be bonded and laminated using a suitable adhesive, it would be difficult to obtain conductivity in the thickness direction of the thin film because the adhesive is an insulator. For these reasons, the reality is that it is very difficult to obtain a conductive thin film that satisfies the above-mentioned high requirements regarding the above-mentioned properties. As a result of intensive studies to solve these problems, the inventors have found that by using a semiconductive composition specially selected for the copper film, the above-mentioned mutual adhesion force can be increased to at least 2 kg/15 mm width. They found that the above problem was solved by significantly improving the results, and completed this invention. That is, in this invention, 20 to 100 parts of conductive carbon is added to 100 parts by weight of ethylene propylene rubber (the following parts are parts by weight) on at least one side of the copper film.
This is a conductive thin film body provided with a semiconductive resin layer made of a composition containing 0.5 to 5 parts of peroxide. The reason why the conductive thin film material according to this invention significantly improves the above-mentioned properties is considered as follows.
That is, the copper film has excellent inherent chemical resistance and water resistance, and the ethylene propylene rubber composition has been found to significantly improve flexibility. A porous oxide film layer of several tens of angstroms is formed on the surface of the copper film, and this is filled with rubber resin to dramatically increase the adhesive force between the two materials, that is, the copper/conductive composition. All of the above characteristics could be improved through a mutual effect. The conductive carbon black used in this invention was manufactured under the trade name Ketschen Black EC (made in the Netherlands).
Akzo Corporation), acetylene black, furnace black, etc. are used, and these are used in an amount of 20 to 100 parts per 100 parts of ethylene propylene rubber, taking into account the above-mentioned conductivity of 10 ⁰ to 10 ⁵ Ω-cm. are mixed. Next, the peroxides used in this idea are:
Hydroperoxide, sialkyl peroxide, sialyl peroxide, ketone peroxide, alkyl perester, peroxydicarbonate, hydrogen peroxide, etc. are used in a proportion of 0.5 to 5 parts per 100 parts of ethylene propylene rubber. It is. If the peroxide is below this lower limit, there is no ability to form a porous oxide film layer on the surface of copper, and therefore good adhesive strength cannot be obtained between copper and ethylene propylene rubber. Moreover, exceeding the upper limit is not preferable because the physical properties of the ethylene propylene rubber itself deteriorate. In this invention, the temperature when adhering the above-mentioned semiconductive composition layer to the copper film is 130 to 160.
It is important that the temperature and pressure be at least 5 kg/cm ² . If the temperature or pressure is outside these ranges, the above-mentioned properties, especially the normally required adhesion strength of about 2 kg/15 mm, cannot be obtained, which is not preferable. The thickness of the copper film used in this invention is 10μ ~
2000μ, and the thickness of the semiconductive resin layer is 20μ to 5000μ. A preferred embodiment of this invention is shown in FIG. 1, where 1 is a copper film and 2 is a semiconductive resin layer. As is clear from the above description and the examples below, this invention provides the copper film with a specifically selected semiconductive resin layer to improve the adhesive strength between the two, thereby achieving the above-mentioned properties. This was a significant improvement, and its industrial effects are very large. This invention will be specifically explained below with reference to Examples. Examples 1 to 2, Comparative Examples 1 to 4 The metal films and conductive resin shown in the following table were pressed under the conditions in the table to obtain a conductive thin film body, and the adhesive strength of the thin body was examined and the results are shown in the table below. It was shown to.

【table】

[Table] According to the results in the above table, it is clear that the characteristics of the present invention are significantly improved compared to the comparative example.

[Brief explanation of the drawing]

The drawing is a cross-sectional view of the conductive thin film body of this invention. 1... Copper film, 2... Semiconductive resin layer.

Claims (1)

[Scope of utility model registration request] At least one side of the copper film is coated with 20 parts by weight of conductive carbon per 100 parts by weight of ethylene propylene rubber.
1. A conductive thin film comprising a semiconductive resin layer comprising a composition containing ~100 parts by weight and 0.5 to 5 parts by weight of peroxide.