Electrostatic ink-jet printing head and method for manufacturing head block thereof

摘要

An electrostatic ink jet printing head comprises a head block (1, 24) made of insulating material having a first surface (24a) and a second surface (24b) which are intercrossing substantially at a right angle. A plurality of ink channel grooves (7, 34a, 34b) are formed on the first surface (24a) and the second surface (24b) in directions perpendicular to a ridge between the two surfaces (24a, 24b). A plurality of recording electrodes (2, 33) are formed on convexities (35) between the ink channel grooves (7, 34a, 34b) and near ejection points (13, 38) located on the ridge. A cover (3, 4, 23) is attached to the head block (1, 24) for covering the ink channel grooves (7, 34a, 34b) and exposing the ejection points (13, 38) to the air. Ink (36) is forcibly circulated by a forcible ink circulation means such as a pump. The recording electrodes (2, 33) are formed in the lower reaches of the ink stream compared to the ejection points (13, 38), and a plurality of electrophoresis electrodes (11, 11a, 11b) are formed in the ink channel grooves (7, 34a) in the upper reaches of the ink stream compared to the ejection points (13, 38). According to the electrostatic ink jet printing head, excessively higher concentration of the toner particles at the ejection points (13, 38) is prevented and stable ejection of the ink (36) from each ejection point (13, 38) can be executed independently of history of ejection of each recording electrode (2, 33), and stable ejection of the ink (36) from definite and precise ejection points (13, 38) can be executed, thereby high precision clear printing is realized with a simple structure of the head and at a low cost. <IMAGE>