Abstract.Inkjet printing has been widely used in many applications and has been studied for many years. However, there are not many systematic researches on the mechanism of jet formation, nor is there any reliable platform that enables us to evaluate jet performance. In this study, an approach to practically evaluate the jet stability of the dropon-demand (DOD) inkjet printing has been proposed, based on which the transient behavior of the DOD drop formation_x000D_ has been studied experimentally for Newtonian liquids with a range of different viscosities (1.0-11 cp) but of a comparable surface tension. For more viscous liquids, the rate of the jet retraction after a pinch-off from the nozzle was found to increase as the thread motion became more sharp and conical as a result of the shape effect. The break-up time of the jet also increased because the rate of capillary wave propagation was lower for more viscous liquids. The jet stability graph, which can be drawn in terms of jet retraction and break-up time, was employed to characterize the jetting stability, and the degree of satellite drop generation was quantitatively evaluated by two critical jet speeds. The effect of an electric pulse imposed on a piezoelectric plate inside the printhead was also studied. The single-peak electric pulse was used in this experiment for simple analysis, and the jet speed variation was measured under different operating conditions. Both the optimal dwell time and the maximum stable jetting frequency were affected by viscosity_x000D_ and they were explained in terms of the propagation theory.

Drop-on-demand Inkjet Printing Drop Viscosity Jetting Stability Jetting Window

de Gans BJ, Schubert US, Macromol. Rapid Commun., 24(11), 659 (2003)
Calvert P, Chem. Mater., 13, 3299 (2001)
Sirringhaus H, Kawase T, Friend RH, Shimoda T, Inbasekaran M, Wu W, Woo EP, Science, 290, 2123 (2000)
Kawase T, Sirringhaus H, Friend RH, Shimoda T, Adv. Mater., 13(21), 1601 (2001)
Szczech JB, Megaridis CM, Gamota DR, Zhang J, IEEE Transactions on Electronics Packaging Manufacturing, 25, 26 (2005)
de Gans BJ, Duineveld PC, Schubert US, Adv. Mater., 16(3), 203 (2004)
Mun RP, Byars JA, Boger DV, J. Non-Newton. Fluid Mech., 74(1-3), 285 (1998)
Christanti Y, Walker LM, J. Non-Newton. Fluid Mech., 100(1-3), 9 (2001)
Christanti Y, Walker LM, J. Rheol., 46(3), 733 (2002)
Cooper-White JJ, Fagan JE, Tirtaatmadja V, Lester DR, Boger DV, J. Non-Newton. Fluid Mech., 106(1), 29 (2002)
Liou TM, Shih KC, Chan SW, Chen SC, Int. Comm. Heat Mass Transfer, 29, 1109 (2002)
Wu HC, Hwang WS, Lin HJ, Mater. Sci and Eng., A373, 268 (2004)
Wu HC, Hwang WS, Lin HJ, Modelling Simul. Mater. Sci. Eng., 13 (2005)
Fromm JE, IBM J. Res., 28, 322 (1984)
Shin DY, Grassia P, Derby B, Int. J. Mech. Sci., 46, 181 (2004)
Shield TW, Bogy DB, Talke FE, IBM J. Res., 31, 96 (1987)
Bogy DB, Talke FE, IBM J. Res., 28, 307 (1984)
Wu HC, Shan TR, Hwang WS, Lin HJ, Mater. Transactions, 45, 1794 (2004)
Lee FC, Mills RN, Talke FE, IBM J. Res., 28, 307 (1984)
Carr WW, Morris JF, Nat. Textile Center Annual Report (2003)
Carr WW, Park H, Bucknall D, Nat. Textile Center Annual Report (2005)
Shore HJ, Harrison GM, Phys. Fluids, 17, 033104 (2005)
Dong H, Carr WW, Morris JF, Phys. Fluids, 18, 072102 (2006)
Talyer GI, Proc. R. Soc. London, Ser, A253, 313 (1959)
Keller JB, Phys. Fluids, 26, 3451 (1983)
Culick FEC, J. Appl. Phys., 31, 1128 (1960)
Brenner MP, Gueyffier D, Phys. Fluids, 11, 737 (1999)
Eggers J, Rev. Mod. Phys., 69, 865 (1997)