Printer nozzles get smaller and smaller to generate increasingly sharper pictures. But such tiny holes through which ink is released can easily get cluttered. Printer manufacturer Océ wants to understand how ink residue builds up inside the nozzles and contacted Han Zuilhof, professor in Organic Chemistry at Wageningen University. Zuilhof can accurately measure the chemical processes inside a nanosized nozzle thanks to the Field Emission Auger Microprobe, top of the bill equipment that is embedded within CAT-AgroFood and that is at his disposal.
“The Auger enables us to measure on a scale of 30 by 30 nanometers”, explains Zuilhof. “That is one million times better than with the X-ray Photoelectron Spectrometer (XPS), which measures an area of 30 by 30 micrometers.” This is how the Auger works: in a vacuum environment and with great precision electrons are being fired at the sample to release signals of the elements of the upper layer of the sample. The properties of these elements are then determined. “This gives us very accurate information of the elements that are found inside the nozzle”, says Zuilhof. Marc van den Berg from Océ clarifies: ”Drops of liquid are pressed through an organic sieve. That sieve has a different coating on the inside than on the outside, where the ink is released onto the object that is being printed. We want to know what happens on the edge where these two coating types meet, right inside the sieve holes.”
The chair group Organic Chemistry also uses the Auger for research into milk and beer processing, Zuilhof says. “The same issues apply there. The production process require membranes, miniscule organic sieves. And like printer nozzles, the holes in these membranes can also get clogged up. These processes happen on such a small scale, that we need the Auger to look inside the holes.” But Zuilhof wants to stress that the Auger has not made the use of their XPS redundant for elemental analysis of surfaces. “Just as the Auger is a fantastic piece of equipment to scan processes on nanometer level, the XPS is great to study phenomena on micrometer scale. And while the Auger provides information on a smaller scale, the XPS data contain more chemical information.”Wageningen UR possesses a wide range of laboratory equipment. CAT-AgroFood provides regional, national and international researchers – both at knowledge institutions and industries – access to the most state-of-the art technological facilities Wageningen UR has to offer.