Xerox Scientist Describes Experiments to Optimize Printheads for Solid Ink Printers
News May 31, 2006
Xerox Corporation has announced the launch of next generation of solid ink printheads, designed through a "rapid prototyping" process, will speed development, increase product quality and may yield information for other industries that need to control the behavior of fluids on a micro scale, according to a Xerox scientist.
In a talk being given at PhAST 2006, John Andrews, a principal scientist in Xerox's Wilson Center for Research and Technology in Webster, N.Y., will discuss "Laser Rapid Prototyping for Designed Experiments in Microfluidics."
The annual conference, sponsored by the Optical Society of America, presents the latest in laser applications, systems and technologies.
Andrews is reporting on experiments in which he systematically varied the size and shape of a printhead nozzle - with an opening one-tenth the diameter of a human hair - and other parts of the fluid delivery structure in order to optimize the placement of ink droplets that the printhead squirts onto paper to form images.
He used rapid prototyping, a process that integrates Xerox's modeling and simulation expertise with laser micromachining, to produce functioning printheads having desirable performance characteristics.
Andrews used a laser to micromachine - or drill - a number of inkjet nozzles, each with a slightly different shape.
By testing the droplet shapes resulting from the various openings, he found that he could use the nozzle plate thickness and the shape of the nozzle's barrel to predict how fast the droplet would travel.
The results from the experiments will enable systems engineers to pick a nozzle design that produces the performance characteristics desired for the system they are planning.
In addition to inkjet printers, other applications where a liquid must be forced through a tiny opening include spraying materials for biological analyses and DNA testing, testing for the presence of chemical agents, shooting droplets of solder to bond chips to a circuit board, and constructing three-dimensional wax parts models by "printing" them.
"Nozzle properties are important," Andrews concludes, "because the nozzle is the last interface between the liquid pool and the air. Nozzle shape controls the speed and direction at which the drop travels as well as its size."
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