Selection method of selection method as well as ink and ink-repellent layer of ink-repellent layer using the slipping speed evaluation method of ink

摘要

PROBLEM TO BE SOLVED: To stably eject ink droplets from a nozzle by easily selecting an optimum combination without generating deterioration by aging of the ink flowability between an ink repellent layer formed on the circumferential surface of a nozzle of an orifice plate and an ink.;SOLUTION: A test piece with an ink repellent layer formed thereon is soaked in the same radiation-hardening type ink as that used for the ink-jet ejecting unit, and then it is pulled out therefrom. The pulled out test piece is fixed in a state inclined with respect to the horizontal surface by 45°. 10-20 μl of the ink is dropped onto the fixed test piece. The same ink repellent layer 9 as the ink repellent layer having the ink repellent characteristics satisfying the slipping rate of the dropped ink based on the slipping rate evaluation method of 2 mm/second or more at 25°C both immediately after soaking and 100 hours after soaking, is formed on the surface 8a on the ink ejecting side of an orifice plate, at least on the circumferential surface of a nozzle 2.;COPYRIGHT: (C)2003,JPO