Img/2012/1/17/printing-small.jpgWashington: Unlike conventional inks used for printing electronics, which are made up of metallic particles, researchers have now developed an all-liquid ink made of a solution of silver and ammonia. According to Jennifer Lewis, a professor of materials science and engineering, and graduate student S. Brett Walker, when printed, the liquid evaporates, leaving a trail of conductive material.
The new ink developed by University of Illinois researchers has quite a few advantages over more conventional electronic ink.
One is the size of the inkjet nozzle that can be used. Inks using particles require bigger nozzles - on the order of a micrometer in size whereas the liquid silver ink requires much smaller nozzles - 100 nanometers.
It is also easier to make than other electronic ink and it sticks to a wide variety of materials, including plastic, paper or fabric, Discovery News reported.
The other big benefit is temperature. A typical particle-based ink has to be printed at a comparatively high temp in order to get good conductivity. That is why they are not used on paper or some plastics.
But the silver-based solution gets to its maximum conductivity at about 90 degrees Celsius, or about 194 degrees Fahrenheit. Despite being warm, it is still cool enough to work most materials.
Another important factor is price. Although silver may sound like an expensive material, it is been between 26 dollars and 48 dollars per ounce over the last year, and an ounce of silver would produce a good quantity of printing ink.
The cost per unit volume would be as good as that of printer inks sold nowadays.
The study has been published in the Journal of the American Chemical Society.
First Published: Tuesday, January 17, 2012, 17:24