COATING MATERIAL COMPOSITION FOR PRECOATED METAL PLATE, WHICH IS LESS LIKELY TO CAUSE ELECTROSTATIC TROUBLES, AND PRECOATED METAL PLATE

摘要

This invention provides a precoated metal plate (PCM) comprising a coating film provided on at least one side of a metal plate, wherein the electrification voltage generated upon the separation and electrification of PCM at room temperature and that at 70ºC by a predetermined method are less than 0.15 kV or less than 0.25 kV, respectively, and the electrostatic capacitance of a coating film in the precoated metal plate having a size of 4 × 4 cm is not less than 5 µF. According to the precoated metal plate (PCM), the occurrence of troubles due to static electricity generated upon friction against a material of which the position on triboelectric series is on minus side as compared with the PCM coating film can be suppressed at each temperature. At the same time, the adherence of foreign matter due to the static electricity generated upon friction against a material of which the position on triboelectric series is on plus side as compared with the PCM coating film can be avoided. The incorporation of not less than 5% by mass and less than 15% by mass, based on the total solid content, of an isocyanate derivative, particularly an isophorone diisocyanate (IPDI) derivative, in the coating material, or the incorporation of not less than 1% by mass, based on the total solid content, of an alkoxyamine salt together with an isocyanate derivative into the coating material is effective for lowering the electrification voltage after separation and electrification. The addition of a high-permittivity material to the coating material or a reduction in film thickness is effective for electrostatic capacitance rise of the coating film.