Additive Manufacturing Conference Review, Part 2

This column is a continuation of the Rapid+TCT Conference review. The previous column focused on panel discussions and presentations by leaders in the additive industry, with an emphasis on the current state and future trajectory of the industry. This column is focused on one-on-one conversations with materials suppliers and printer vendors, transitioning from strategy at 30,000 feet down to the ground level where materials and machines are developed and tested.

Materials Update

Rob Clemons, innovation project manager for Henkel, outlined some of the current challenges he is facing. As described in the previous column, dental applications are a key focus area for vat polymerization. A 510(k) draft guidance for dental composite-resin devices was published by the FDA in July 2024, a revision of the document previously issued in 2005. Clemons stated the importance of standards harmonization, as well as ISO and USP Class VI certification and GMP designation. Clemons also mentioned the continuing need for vat resins with the acrylic-like properties of rigid or semi-rigid plastics. Henkel’s MED3394 is CMR-free and ISO 10993-compliant for surgical tooling, including autoclavability. 1

Sharon Soong, head of Materials R&D, discussed some of the ongoing materials needs at Formlabs. There continues to be a need for materials with properties closer to thermoplastics, but also with a better cost and post-processing profile than currently available materials. Dental applications are a better match to the profiles of currently available materials, but improved photoinitiators still are needed.

Brad Rosen, global business director for 3D Printing Solutions at Arkema, outlined the strategy, challenges and opportunities in the UV additive market. From the resin-performance perspective, key attributes are durability, flame retardancy and print speed. Raw material sustainability and human health continue to be a focus. Rosen also discussed Asian supply challenges, the difficulty of new material registration and the limited utility of polymer exemptions where small molecule development is needed are well known, and customers are familiar with these constraints. The biggest opportunities that Rosen sees are in the industrial space, after overcoming the barriers to entry of UV, and in the medical/dental space. Remote production is an enabling factor for additive, but controlling material properties in the user environment is a challenge, and universally applicable solutions are not possible. Medical materials, such as tissue scaffolding, face challenges such as regulatory and compliance approvals

Advances in Printer Technology

Formlabs released an LCD-based vat printer that is significantly faster than its SLA printers. The wiper used in the SLA printer still is present in the DLP version to aid in material flow, which is critical as the demand for both formulation viscosities and print speeds increase. 2 Resins have been reformulated for the change in light source, and a new non-flammable biodegradable replacement for isopropanol in the wash step has been commercialized.
Nanzhu Zhao, senior researcher at the Nissan Technical Center, discussed efforts by the automaker to enhance efficiency and sustainability, including the collaboration between Nissan and Northwestern University using the HARP technology. 3 Their current benchmark is 1 cm/s linear printing speed on a small-scale printer, and the collaborators are projecting up to 3,600 cm/hour in a 400 x 400 x 400 mm build volume on a prototype currently under construction.

Julie Kuhrt, head of Marketing for Quantica GmbH, discussed the ongoing commercialization of high-viscosity inkjet printhead technology. Typical additive inkjet properties are between 10-15 cP at up to 80° C. The Quantica printheads work with viscosities up to 250 cP at 80° C and up to 5 micron D90 particle diameter. 4 The technology enables multimaterials with a higher particle loading or higher oligomer loading than conventional printheads to produce a wider range of properties.

Takeways from the conference include:

  1. As a whole, the additive industry is undergoing consolidation as profitability is a focal point.
  2. UV resin printing platforms continue to evolve.
  3. The demand for new materials enables new applications and provide better solutions to current applications.
  4. Medical and dental applications increasingly are important high-value applications. The results truly are inspiring. 5

References

  1. Typical autoclave sterilization conditions are 20 minutes at 121 C under 15 psi steam pressure. https://www.masterbond.com/articles/autoclave-resistance-medical-adhesives, accessed 9/26/24
  2. https://support.formlabs.com/s/article/Quick-Start-Guide-Form-4?language=en_US, accessed 9/26/24
  3. Walker, D.A.; Hedrick, J.L.; Mirkin, C.A. Rapid, large-volume, thermally controlled 3D printing using a mobile liquid interface Science 2019, 366, 360-364
  4. https://www.q3d.io/novojet-printhead accessed 9/26/24
  5. https://www.mayoclinic.org/departments-centers/anatomic-modeling-laboratories/overview/ovc-20473121, accessed 9/26/24

Paul Share, Ph.D.
Principal Consultant
Advanced Materials Design LLC

RELATED ARTICLESMORE FROM AUTHOR