PURPOSE: To prevent the generation of NOx in a time of electric discharge by providing an electrode for forming electrolysis on one side of a fine ceramic material and laminating both a barium titanate layer and the electrode for forming electrolysis on the other side and thereby molding a discharge material for generating the ions.

CONSTITUTION: A barium titanate layer 3 is integrally provided on one side of a fine ceramic material 1 by a screen process and a flat electrode (tungsten) 4 for forming electrolysis is integrally provided on the layer 3 by the screen process. Thereafter thirteen parallel fine linear electrodes (tungsten) 2 for forming electrolysis are directly provided on the residual one side of the fine ceramic material 1 by the screen process and the connection parts 7, 8 for the lead wires made of an ally of Ag, Pd on the one part of the electrodes 2, 4 to obtain a discharge material for generating the ions. The ions wherein the generation of NOx is a little are generated by impressing 7kHz high frequency and 700V AC high voltage on the electrodes 2, 4 of this discharge material.