Functional surfaces with self-cleaning property are highly desirable in many applications in the printing industry. One of the challenges in fluid ink jet systems is ink wetting and drooling onto the printhead front face. The contamination of the printhead front face leads to missing drops, wrong-sized drops, mis-directionality, and satellite drops resulting in degraded print quality. In this study, we report the creation of textured surfaces on Si wafer by photolithography, followed by chemical modification, that leads to superoleophobic, directional self-cleaning surfaces. We systematically investigate its wetting and adhesion properties with water, hexadecane and Xerox solid ink using static and dynamic contact angle measurement techniques. The textured surfaces are made of micro grooves which demonstrate interesting anisotropic wetting behavior. In the direction parallel to the grooves, low surface tension testing liquids show very low sliding angle (i.e. directional self-cleaning) which is a key enabler for the selfcleaning effect and maintenance free printhead.
Hong Zhao, Kock-Yee Law, "Directional self-cleaning surface design for ink jetting devices" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP26), 2010, pp 171 - 173, https://doi.org/10.2352/ISSN.2169-4451.2010.26.1.art00048_1