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Breakthrough printing technique uses sound waves to control droplet size

Research by Harvard University scientists could expand the range of optical and biopharmaceutical materials that can be created


Harvard University researchers have developed a new way of controlling the size of droplets using sound waves.

The research, which was published in Science Advances, means that a wider range of liquids with varying viscosity and composition can be used in droplet-based printing.

It could lead to the manufacture of new biopharmaceuticals, cosmetics and food, while also expanding the range of optical and conductive materials that can be created.

The technique, named acoustophoretic printing, involves using sound waves to aid gravity.

Sound waves pull each droplet from the printer nozzle when they reach a certain size and the liquid drops towards the printing target.

A high amplitude of sound waves results in a small droplet size, no matter how viscous the fluid is.

Before this advancement, liquids could only be used that were around 10 times more viscous than water.

Image credit: Harvard University