Abstract: This invention relates to an inorganic colorant, to a paste made from that colorant by dispersing that colorant into a vehicle, and to a water based paint made using either these colorants or pastes. This invention involves an improvement of the dispersibility of the inorganic colorant into a dispersion medium by which that inorganic colorant, having polar groups on its surface, is treated by low temperature plasma polymerization of a substantially non-polar monomer to form a non-polar group on the surface of the inorganic colorant. The inorganic colorants, to which this invention is applied to improve their dispersibility, are of a wide variety of species. According to the invention, due to the great improvement in the dispersibility of the inorganic colorants, the possible range of formulation of inorganic colorant and the dispersion medium is enlarged.

Abstract: An object of the invention is to present a corona discharge processing apparatus capable of performing uniform and excellent corona discharge processing, on work of any thickness or shape, with the constant processing effect regardless of a thickness and shape of the work.A corona discharge processing apparatus of the invention comprises an excitation electrode and a counter-electrode, and generates a corona discharge by applying a high voltage between them, thereby applying corona discharge processing on the work, wherein the excitation electrode and the counter-electrode are both disposed on the same surface of the work with an interval between them.