1. DIGITAL PRINTING TECHNOLOGIES R.B.Chavan Department Of Textile Technology Indian Institute of Technology Hauz-Khas, New Delhi 110016

6. SINGLE JET SYSTEM

14. Milliken Millitron Air jet deflection

20. Piezo crystal technology A typical construction comprises an array of nozzles, each with its own piezoelectric crystal. Since no deflection of droplets is needed, guttering and recirculation are not required, which simplifies the design and construction of the printer.

21. Principle of drop-on-demand and piezoelectric ink jet printer

23. Electric charge causes a shearing action in the distortion of the PZT piezoplates against the ink causing ink drops to eject from the nozzle

25. Manufacturers: Tektronix, Sharp, Epson. The advantages of these heads are that they form very accurate circular droplets, and they are mass produced and low cost. Their disadvantage lies in the requirement of extremely low viscosity inks of about 1.6 to 3 cp.

26. MANUFACTURERS:Dataproducts, Trident and Epson It is a relatively high energy process. ejects droplets which are more elongated They are relatively robust and can use inks in the 10 to 20 cP range.

27. Seimens successfully marketed this technology for office printing. In this mode, electrical charge deforms a piezoceramic tube so that it squeezes the ink within the tube forcing it out through the nozzle end.

28. Combines shear mode with bend mode technology to squeeze and push ink through its nozzles. Relatively fast and robust printheads. Use a range of ink types. Relatively fast processing speeds and the ability to produce variable droplet sizes with higher viscosity inks than thermal inkjet.

32. Bubble jet printer: (a) bubble jet chamber; (b) bubble formation

34. Thermal ink jet or bubble jet technology