Concordia researchers introduce Proximal Sound Printing for 10× smaller features

Concordia University researchers led by Shervin Foroughi, Mohsen Habibi and Muthukumaran Packirisamy report a new ultrasound‑driven 3D printing method called Proximal Sound Printing, which the team says yields features up to ten times smaller than earlier sound‑based approaches while consuming significantly less power and improving repeatability. The work appears in the journal Microsystems & Nanoengineering and frames PSP as a simpler, single‑step workflow for printing directly onto soft polymers such as silicone.

The advance builds directly on the team’s prior “direct sound printing” demonstrations, which established that ultrasound could cure polymers on demand but struggled with limited resolution and consistency. “This work builds on the research team's earlier breakthrough in direct sound printing, which first showed that ultrasound could be used to cure polymers on demand. While that earlier method demonstrated the concept, it struggled with limited resolution and consistency. The new proximal approach places the sound source much closer to the printing surface, allowing far tighter control,” said Muthukumaran Packirisamy, professor in Concordia’s Gina Cody School of Engineering and Computer Science.

Technically, PSP relocates the acoustic source into a proximal configuration so that focused ultrasound delivers energy much closer to the liquid polymer interface. Media descriptions and the Concordia release describe focused ultrasound triggering chemical and sonochemical reactions that solidify liquid polymers exactly where printing is needed; the proximal geometry reduces required acoustic power and tightens spatial control, producing the reported up to 10× improvement in feature size compared with the earlier direct sound printing geometry.

The team highlights material compatibility with soft, flexible substrates that are hard to print with heat‑ or light‑based methods. Sources list silicone and other soft polymers explicitly, and identify potential targets including microfluidic channels, lab‑on‑a‑chip diagnostic platforms, wearable devices, soft robotics components, flexible sensors and environmental monitoring devices. Eurekamagazine and Concordia materials also suggest the increased precision may enable multi‑material structures in a single process, while 3dprintingindustry emphasizes a streamlined single‑step workflow for complex microscale parts.

Authorship and support details named in the release identify Shervin Foroughi as the PhD lead or recent PhD graduate, Mohsen Habibi with an affiliation that includes University of California at Davis, and Packirisamy as the Concordia faculty lead in the Department of Mechanical, Industrial and Aerospace Engineering. The project lists funding support from the Natural Sciences and Engineering Research Council (NSERC).

Press summaries and media excerpts emphasize relative gains but omit absolute metrics that matter to makers. The public descriptions do not provide numerical lateral resolution in micrometers, ultrasound frequency or intensity, transducer geometry, or quantified power consumption. For full performance numbers, micrographs and experimental parameters, consult the Microsystems & Nanoengineering paper and the Concordia release for figures, DOI and methods.

Proximal Sound Printing positions ultrasound as a practical manufacturing tool for delicate materials rather than a laboratory curiosity. If the claimed up to 10× feature shrinkage and lower energy demand hold up under peer review and replication, PSP could cut prototyping time for silicone microfluidics and wearable sensor runs and open a pathway from lab demos to small‑scale production for soft electronics and diagnostic microdevices.