PRINTING, CIRCUIT BOARD AND PRINTED-CIRCUIT BOARD MOUNTING STRUCTURE

PROBLEM TO BE SOLVED: To ensure insulation of a prints along with the adhesion of the prints by using a pigment white ink obtainable by forming a light-hardening agent and a metallic oxide into a liquid state with a solvent by an ink jet system and to enable the printing work of circuit symbols, layout symbols and the like, such as characters to show electronic component mounting positions on a printed-circuit board or the like. SOLUTION: Printing is conducted on a board 1 using pigment white ink obtainable by forming a light-hardening agent and a metallic oxide in a liquid state with a solvent by an ink jet system. As the solvent, an alcoholic solvent is used and printing is conducted by a printing heat part 2 constituting an ink jet printer. That is, the pigment white ink is previously filled in an ink cartridge 5 and the white ink is sent to the head part 2. After the ink is stored in the head part 2 to a certain degree, the head part 2 starts action, the white ink is jetted and discharged through a group of ink discharge orifices, which consist of a plurality of ink discharge orifices, and circuit symbols and layout symbols are printed on the board 1 at high speed.