| 摘要 |
<p>A process for the passivation of the channel walls of an ink jet print head channel of ceramic piezoelectric material and which enables the deposition of a continuous coating on the walls of a deep channel without depolarising the material comprises depositing a coating comprising inorganic material by: (a) providing an ink jet print head component containing said channel and (b) while maintaining the bulk temperature of the actuating component which contains said channel at a temperature of below 200 °C and at which not more than 30 % depolarisation of the material occurs during passivation, exposing the surface of the channel walls to be passivated to a homogenised vapour of the coating material, said vapour having undergone multiple scattering during transport thereof from the source of the vapour to said surface. The process may be employed to deposit a plurality of layers which may be of differing composition, and the invention also provides ceramic piezoelectric ink jet print heads the channels walls of which have been coated with particular combinations of layers of differing compositions.</p> |
