PRINTING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a printing apparatus which prevents printing particles from scattering during flying, thereby obtaining dots of a suitable size and a suitable density. SOLUTION: A printing head 50 has holes 56 through which printing particles 38 can pass. Trigger electrodes 58 are disposed in the circumference of each hole 56. A thickness (d) of the electrode in a direction in which toner particles fly is set to be larger than a layer thickness d1 of the toner particles 38 held by a developing roller 30 and a distance d2 between the developing roller 30 and the printing head 50. An aggregate of the toner particles 38 flying in the hole 56 is accommodated inside an area surrounded by the trigger electrodes 58 and converged when a pulse voltage is turned off. As a result, an outline of a dot becomes clear and an image formed as a cluster of the dots is highly fine.