TL;DR they make a droplet on a capillary tip and use the radiation pressure of sound to push it off, enabling printing with liquids with viscosities ranging over four orders of magnitude.
It's cool, but in the current approach they still need to produce a somewhat spherical droplet in order to apply downward radiation pressure from sound. So it would be hard to apply to printing of thermoplastics which might be more prone to forming tubes rather than droplets. The fact that they need a 3d droplet is another thing that will make scaling this approach interesting. Because we need a somewhat complicated 3d structure, which is a capillary tip inside a tube which needs to be longer than the droplet by some factor due to the wavelength of sound, this is going to be challenging to fabricate in bulk at the microscale like we do with today's inkjets. One might even need fairly exotic processes like LIGA to fabricate structures with this aspect ratio.[0]
It may not end up being a mainstream droplet jetting technique, but the fact they can jet liquids over four orders of magnitude is pretty compelling. Especially for research purposes
Also, the materials and methods is somewhat entertaining. It's not often that you see white chocolate, which they used as a substrate to print honey droplets on to, listed as a material used. Tuning the parameters was probably pretty tasty
It's cool, but in the current approach they still need to produce a somewhat spherical droplet in order to apply downward radiation pressure from sound. So it would be hard to apply to printing of thermoplastics which might be more prone to forming tubes rather than droplets. The fact that they need a 3d droplet is another thing that will make scaling this approach interesting. Because we need a somewhat complicated 3d structure, which is a capillary tip inside a tube which needs to be longer than the droplet by some factor due to the wavelength of sound, this is going to be challenging to fabricate in bulk at the microscale like we do with today's inkjets. One might even need fairly exotic processes like LIGA to fabricate structures with this aspect ratio.[0]
It may not end up being a mainstream droplet jetting technique, but the fact they can jet liquids over four orders of magnitude is pretty compelling. Especially for research purposes
Also, the materials and methods is somewhat entertaining. It's not often that you see white chocolate, which they used as a substrate to print honey droplets on to, listed as a material used. Tuning the parameters was probably pretty tasty
[0]https://en.wikipedia.org/wiki/LIGA