US EPA

1322354 

Journal Article 

A New Method to Assess the Jetting Behavior of Drop-on-Demand Ink Jet Fluids 

Jung, S; Hoath, SD; Martin, GD; Hutchings, I 

2011 

Yes 

Journal of Imaging Science and Technology
ISSN: 1062-3701 

I S & T - SOC IMAGING SCIENCE TECHNOLOGY 

SPRINGFIELD 

55 

1 

105011-105016 

English 

10.2352/J.ImagingSci.Technol.2011.55.1.010501 

WOS:000287563500003 

We present a new experimental method to assess the jetting
performance of fluids for use in drop-on-demand (DOD) ink jet printheads. The oblique collision
of two continuous liquid jets leads to the formation of a thin oval liquid sheet bounded by a
thicker rim which disintegrates into ligaments and droplets. Under certain conditions the flow
structure exhibits a remarkably symmetrical ""fishbone"" pattern composed of a regular succession
of longitudinal ligaments and droplets. For a series of model elastic fluids containing
polystyrene (PS) in diethyl phthalate (DEP), and also for solutions of polyethylene oxide (PEO)
in glycerol/water, ejected from nozzles with an internal diameter of 0.85 mm, the shape of the
fishbone pattern varies strongly with polymer concentration. The same fluids were also used in a
Xaar piezoelectric DoD print head to characterize their jetting performance in terms of the
maximum ligament length, a crucial parameter in determining the printability of the fluid. There
are close similarities between the ligament collapse behaviors in both experiments. Good
correlation was found between the maximum included angle of the fishbone pattern and the maximum
ligament length in the jetting experiments, which suggests that a test based on oblique impinging
jets may be useful in the development of fluids for ink jet printing. (C) 2011 Society for
Imaging Science and Technology [DOI: 10.2352/J.ImagingSci.Technol.2011.55.1.010501]