With a dense mist of fine ink droplets(typically about 50 nL/cc)generated from an effective liquid atomizer,the Aerosol Jet(R)direct-write system can deliver unique capability of precision material deposition for producing fine-feature electronic,structural,as well as biological patterns onto almost any substrate of arbitrary shape(cf.http://www.optomec.com/additive-manufacturing/printed-electronics/aerosol-jet-technology/).The feature size can be as small as about 10μm,and the wet material throughput from a single deposition nozzle may become more than 5 μL per minute(e.g.,at 100 ccm mist flow rate).The performance of Aerosol Jet(R)technology relies on the mist generation effectiveness of the atomizer for a given ink,as well as adequate solvent removal rate from the ink droplets prior to their deposition.For effective atomization,inks with lower viscosity which typically correlates to lower solid contents are usually desirable.In contrast,for high quality printing at high deposition rate,the ink droplets with higher viscosity corresponding to higher solid contents on substrate are often helpful.In fact,the ink formulated for Aerosol Jet(R)printing typically contains both volatile and nonvolatile solvents,with the volatile solvent easily removed by evaporation while having the nonvolatile solvent to retain cohesivity of printed features for further adequately controlled solidification processing.Thus,understanding the evaporation characteristics of multicomponent ink droplet is important for various application recipe development.In this work,analytical formulas are presented for evaluating vapor transport of a volatile solvent for an isolated multicomponent droplet in a quiescent environment,along with an illustrative description of the Aerosol Jet(R)technology.For evaporating droplet,the droplet size is predicted to often decrease at an accelerated rate in the beginning,but at a diminishing rate toward the end due to the presence of nonvolatile cosolvent.Such an acceleration-deceleration reversal behavior is unique for evaporating multicomponent droplet,while the droplet of pure solvent has an accelerated rate of size change all the way through the end.This reversal behavior is also reflected in the droplet surface temperature evolution as "S-shaped" curves.Moreover,the derived formulas can also be applied to droplet growth by condensation with unique phenomena being predicted.