Powder additives for coating materials or for plastics.

摘要

The present invention provides a powder additive for coating materials, plastics, or rubbers comprising particles of a metal or glass, the particles each having a thickness of 0.5 to 5 micrometres, a minor axis/major axis of from 5 to 500 micrometres, an aspect ratio (ratio of the major axis to the thickness) of not less than 5, and a ratio of the minor axis to the major axis, of from 1 to 10, and the particles being leaf-shaped. This powder can readily cause the leafing phenomonon when added to coating materials which are then applied as a coating hence the coating surface can be effectively covered with the powder, so that it can impart superior corrosion resistance and weathering resistance as compared with conventional powders. It can also impart superior electromagnetic shielding properties when added to plastics or rubbers.