Inkjet printing of phase-change or hot melt materials allows to produce etch masks by digital and additive processing, thus enabling highly efficient fabrication of printed circuit boards, solar cells etc. Previously the binary inkjet printing with drop volumes of 50 pL was demonstrated with Xaar126 end-shooter printheads. The present work describes new results on printing with Xaar1001 printheads. These printheads offer both, grayscale printing with a subdrop volume of 6 pL and excellent reliability by way of their unique ‘true throughflow’ capability, respectively.While the advantage of grayscale printing for high-resolution patterning is obvious and straight forward, the complexity lies in the recirculating ink systems that provide the constant ink flow through the printhead channels. A narrow temperature range has to be established throughout the total ink path, which avoids hot spots that would damage the inks as well as cold spots that counteract the ink flow rate. Print results with Sunjet Crystal HEP9520, operating between 80 °C and 90 °C, clearly show good droplet formation for 7 distinct gray levels spanning a range from 5 to 37 pL with increments of 5.3 pL at a frequency of 5 kHz.
Ingo Reinhold, Werner Zapka, Wolfgang Voit, Frank Steinhäußer, Moritz Stürmer, Andreas Madjarov, Markus Völker, "Inkjet Printing of Phase-Change Materials With Xaar1001 Printheads" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP26), 2010, pp 319 - 322, https://doi.org/10.2352/ISSN.2169-4451.2010.26.1.art00084_1