1. Ink jetting sami.franssila@aalto.fi

2. Drop-on-demand ink jet

3. Ink jet firing sequence

4. Continuos ink jet (CIJ) Derby: Annu Rev. Mater.Res 2010

5. Numbers nozzles 20-30 µm in diameter droplet volumes 10-20 pl pixel size on paper 50 µm shooting frequency up to 10 kHz

6. Ink jet imaged P.Koltay (IMTEK, Freiburg) in Oosterbroek: Lab-on-a-Chip

7. Reynolds number (Re) ratio of inertial to viscous forces Re = ρνD/η ρ = density of fluid (kg/m3) ν = linear velocity (m/s) D = dimension of the system, diameter (m) η = viscosity of the fluid (Pa*s = kg/m*s) viscosity is the quantity that describes a fluid's resistance to flow small Re means large viscous forces

8. Weber number Transducers 2007 p.165

9. Ohnesorge number Transducers 2007 p.165

10. Ink jet regimes

11. Fluidics (3) Transducers 2007 p.165

12. Ink properties (1) ink viscosity: 8-15 mPa*s, 20 mPa*s limit (water 1 mPa*s) surface tension: 28-35 mN/m, even 350 (water 72 mN/m) higher temperature, viscosity down (  able to print high M w polymers) particles difficult: clogging

13. Ink properties (2) Water-Based Ink Jet Ink Ingredients AmountFunction Water50%-90%Ink Solvent Colourant1%-15%Colour Source Co-Solvent/Humectant2%-20%Ink vehicle, prevents evaporation Fixative/Penetrant0%-10%Assist fixing the ink to substrate Surfactant0.1%-6%Surface tension and wetting Resin0.2%-10%Durability and adhesion Biocide0.02%-0.4%Prevents bacterial growth Fungicide0.01%-0.4%Prevents fungal growth Buffering Agent0.05%-1%Control ink pH level Other0.01%-1%Controls specific characteristics http://www.mrinkjet.com/inkreport.htm

14. Thermal ink jet in silicon

15. Thermal ink jet MEMS Handbook

16. Top shooters

17. Sideshooter

18. Arrays of nozzles Gad-el-Hak: MEMS Handbook

19. Graphic printing vs. Functional materials printing Functional materials perform something, Conduct electricity Respond to enzymes Show iridicence Bend mechanically Host cells

20. Line definition: droplet spacing & overlap Silver nanoparticle printing of conductor lines. a)Droplets too sparsely b)Wavyness still seen c)Optimal d)Too much liquid leads to bulging

21. Drop spreading & temperature Substrate temperature is a standard variable in ink jetting experiments. It directly affects surface tension and viscosity and therefore spreading on substrate.

22. Film formation

23. Surface coverage

24. Nanoparticle inks Murata

25. Metal salt inks

26. Ink jet etching I.M. Hutchings: Ink-jet printing in micro- mabufacturing, 4M/ICOMM 2009

27. 3D ink jetting I.M. Hutchings: Ink-jet printing in micro- mabufacturing, 4M/ICOMM 2009

28. Competition: Laser-assisted maskless microdeposition Alemohammad: J. Micromech. Microeng. 18 (2008) 115015 (12pp)

29. Laser-assisted maskless microdeposition (2) Alemohammad: J. Micromech. Microeng. 18 (2008) 115015 (12pp)

30. The MDDW method makes patterns on the substrate by pumping the slurry of suspended nanometal powders. Since it does not rely on the spray mechanism but direct contacting mechanism, it allows to avoid or minimize the ink from oxidation or reduction during the printing process. MDDW: microdispensing deposition write

31. M3D: maskless mesoscale materials deposition M3D method uses a mechanically or ultrasonically driven device to stir and mix the suspended nanometal powders injecting the slurry through an orifice as a mist with the help of an air injection mechanism. M3D and MDDW devices have been developed beyond the capability that the ink-jet method can perform in handling high viscous materials and they can even handle three-dimensional patterns.

33. Ink jet dichotomies thermal vs. piezo continuous vs. drop-on-demand (DoD) free pressure vs. free flow boundary conditions printing on porous vs. hard surfaces (paper vs. overhead transparency) printing vs. film formation 2D patterns vs. 3D structures solutions vs. particle-containing inks

34. Ultimate resolution ?

35. Creating cell patterns Ink jet printing of PLGA polymer on PS substrate. Cells attach to PLGA but not on PS.

36. Ink jetting bacteria

37. Printing DNA arrays

38. Promise: fewer process steps  faster, cheaper electronics Murata et al: Microsyst Technol (2005) 12: 2–7

39. Applications: antennas (c) Inductive coil printed on fabric. (d) RFID antenna with metallic joints printed on paper. J. Micromech. Microeng. 17 (2007) 967–974 S M Bidoki, D M Lewis, M Clark, A Vakorov, P A Millner and D McGorman:

40. Applications: 3D N. S. Kim, A. K. Amert, S. M. Woessner, S. Decker, S. M. Kang, and K. N. Han International Conference on Nano Science and Nano Technology, GJ-NST 2006, Korea Institute Industrial Technology,Gwangju, South Korea, 7–8 December 2006. Antenna print on a combat helmet surface by the MDDW technique. Ko & Grigoropoulos: JMM 2010 125010

41. Printing metallization I.M. Hutchings: Ink-jet printing in micro- mabufacturing, 4M/ICOMM 2009

42. Printing insulators I.M. Hutchings: Ink-jet printing in micro- mabufacturing, 4M/ICOMM 2009

43. Printing polymers I.M. Hutchings: Ink-jet printing in micro- mabufacturing, 4M/ICOMM 2009

44. Printing further I.M. Hutchings: Ink-jet printing in micro-mabufacturing, 4M/ICOMM 2009