Engineering of future digital printing technologies

Digital printing technologies have increasingly been used in industry for the production of personalized or new products and are expected to play a key role in the Industry 4.0 revolution, hopefully resulting in a more sustainable production. Nevertheless, to make this possible, such complex printing technologies must be further improved. There are therefore numerous engineering challenges that have to be addressed. Additionally, the development of a digital printing process is a truly interdisciplinary work. In this one-week summer school, the different elements of inkjet printing will be covered, from the ink to the printer, with a mechanical, electrical, mechatronic and control points of view. Focus will be laid on inkjet printers design, on inkjet print heads and their electronics, and on ink supply systems. Students will apply their knowledge learned during the studies to this very interdisciplinary field. The summer school will combine remote and on-site courses with practical work in iPrint state-of-the-art laboratories. Students will also have the chance to visit Polytype AG, the world leader in printing machines for cups and bottles.

Students from the following profiles: Electrical Engineering, Mechatronics & Automation, Mechanical Engineering, Medical Engineering, Microengineering, Photonics. No other prerequisites.

Inkjet is a complex technology and an excellent example where interdisciplinary communication and work is essential. While acquiring key theoretical and practical knowledge necessary to develop an inkjet-based digital printing process and technology, students will also discover the importance of exchange between the disciplines. 

The course will include all aspects necessary for inkjet printing: the ink (material to be printed), the substrate and of course the printer, which has to bring the ink on the substrate in a digitally controlled way.

During an online session, inkjet printing will be introduced, together with some bases on inkjet inks and substrates. Such bases, as for instance the different ink types, the relevant physico-chemical and rheological properties, their interaction with the substrate and the possible pre- and post-treatments, are pivotal to understand why and how the inkjet printing technology works. Students will have then time to deepen their understanding through the reading of literature papers that will be provided.

The heart of the Summer School is the full week at iPrint, where the students will have the unique opportunity to do a one-week full immersion in a leading inkjet research institute and learn from experts of iPrint and other industry partners of the Inkjet Ecosystem around iPrint (Polytype, Droptimize, EPSON, Markem-Imaje, etc.) and practice on state-of-the-art platforms. The week will start with a lab session on inks and substrates, to consolidate what has been seen during the first online course. Equipped with the basics on inks and substrates, students will attend a course on the design of inkjet printers, which will be followed by practical work in the lab on mechatronics aspects of inkjet printing. The first day will finish with a visit of the iPrint laboratories to discover the cutting-edge research ongoing at the institute and comptence center.

During the second day, students will learn about drop-on-demand piezo-based inkjet printheads, starting with a course and continuing with laboratory work. In the latter, students will first perform drop watching experiments (i.e. observing the jetting of droplets in air), before printing full images on a substrate.

The details of the pathway through which the digital data representing an image is processed and sent to the printhead for printing (so called "datapath") will be the subject of the third day. After a theoretical course, students will have sufficient time to apply the knowledge in the laboratories.

In order to successfully print an ink on a substrate, the ink has to be delivered to the printhead with precisely controlled parameters (e.g pressure and flow-rate). Students will learn why this is important and how this can be done through an ink delivery system. As for the other days, practical sessions in the lab will complement a first theoretical overview of the subject.

To finish the on-site part of the Summer School, the last day is dedicated to the discovery (course &  lab) of some applications of inkjet: graphical printing, printing for electronics and 3D printing (material jetting and binder jetting). The groups and topics for the mini-project will be also defined. The visit of Polytype AG, the world leader in printing machines for cups and bottles, will close the week in Fribourg.

The detailed program of the Summer School is

• Online (10h)
  • General introduction to course: motivation, objectives, program (course)
  • Introduction to inkjet (course + e-learning)
  • Introduction to inks and substrates (course)
• On-site (42h)
  • Monday
    • Inks & substrates (lab)
    • Printer design (course)
    • Mechatronics (lab)
  • Tuesday
    • Printheads (course)
    • Printheads (lab)
    • Printing (lab)
  • Wednesday
    • Driver electronics and software (course)
    • Driver electronics and software (lab)
  • Thursday
    • Ink delivery system (course)
    • Ink delivery system (lab)
  • Friday
    • Inkjet applications (course)
    • Inkjet applications (lab)
    • Definition of mini-projects
    • Polytype AG visit
• Mini-project (38h)
  • work in group
  • several topics in mechanics, electronics, micromechanics, photonics, software will be proposed to the students
  • on-site or remote

evaluation on the delivered report