UNIVERSITY PARK, Pa. — If you look at the back of a credit card, a driver’s license, or even a dollar bill, you will likely notice a hologram, or iridescent feature, that appears to change color when viewed at different angles. These color-shifting security features have been around for decades, allowing ample time for people to find ways of counterfeiting the effects. Even so, these types of highly visible and easily recognized color-shifting features are still among the most commonly used optical security element — and Penn State-affiliated startup Chromatir may have discovered a more secure and customizable way to implement this effect.

“The origin of Chromatir started with a discovery in our lab that developed into some really interesting applications,” said Caleb Meredith, Chromatir co-founder and CEO and doctoral candidate in the Department of Materials Science and Engineering. “Creating iridescence typically requires materials to be patterned with very small nanostructures which cause light to undergo interference when it gets reflected. We realized there is actually another way to produce interference using a different type of reflective geometry 100 or even up to 1,000 times larger in size, leading to unique color-shifting appearances.”

These microstructures can be used to create color-shifting coatings which, unlike the typical iridescent nanostructures, are more customizable due to their size and shape. By using this new class of microstructures, security features can be designed that are more tunable in their colors and patterns.

“A traditional hologram is basically a bunch of dots or lines — you can change the spacing of the structures or their width, but it can only be controlled along one or two dimensions,” said Meredith. “Whereas, with the microstructures we are designing, you’re playing with geometries in 3D, and so there are more degrees of freedom by which we can use to control the shape. You can make a structure wider or deeper, change the slope of its sides, make it into a polygon or a donut shape — varying the shapes in each of these ways lead to differences in light’s reflections that result in subtle changes in color-shifts. By controlling the shapes of the microstructures, you control the color.”

Co-founders Lauren Zarzar, assistant professor in the Eberly College of Science, and Meredith published their original discovery of the optical mechanism in Nature led by Amy Goodling in 2019, a few years after the initial observation. After publishing, they started considering how the technology could be developed into a possible application for licensing, or eventually the core of a feasible business, and this year they officially incorporated Chromatir as an LLC.

“A lot of important developments recently have been on the customer discovery side,” Meredith said. “We’ve been able to talk to lots of different companies about security, packaging, and other decorative applications, and learn about what their problems are and where we think we can present solutions.”

Although Meredith and Zarzar are currently focused on the security applications of their color shifting films, they are also investigating other applications, such as decorative graphics for vehicles, consumer packaging, and apparel, as well as reflective road signs and color changing sensors.

To take Chromatir’s technology from just an idea in a lab to a potential product on the market, Meredith and Zarzar have acquired mentors through the many entrepreneurial resources at Penn State.

Chromatir participated in the 2019 Invent Penn State Venture & IP Conference Tech Tournament, where the startup was awarded the People’s Choice Award for $10,000. The co-founders also won a $20,000 grant through the 2021 Lab Bench to Commercialization (LB2C) program in the Eberly College of Science, participated in the 2020 Ben Franklin Technology Partners TechCelerator, and took part in the 2021 Board of Advisors program through the Startup Leadership Network.

“The Board of Advisors program has provided me a lot of accountability,” Meredith said. “Between quarterly meetings and updates to the board, it has been a great experience practicing those responsibilities. It also keeps me focused on the bigger picture for the company and the commercialization milestones that I need to be working towards as we try and get out of the lab."

In addition, Chromatir received a $250,000 National Science Foundation (NSF) Partnership for Innovation Grant and participated in the 2021 NSF I-Corps national program. During this program, Meredith and Zarzar conducted over 200 customer discovery interviews to gain a better understanding of the problems addressed by their technology and who their customers are.

“To be able to take a fundamental scientific discovery and see it through to application, trying to think about how your science can actually have an impact on the world outside of the laboratory - it's a difficult process,” Zarzar said. “There have been a lot of bumps along the way and a lot of failures, so just going through the process in it of itself and get this far is something to be proud of.”

Meredith said Chromatir is close to completing a large manufacturing trial to validate the scalability of the color shifting films using roll-to-roll coating processes. Meredith is also participating in the inaugural On Deck Deep Tech Fellowship, an international cohort-based virtual program for scientists and entrepreneurs interested in commercializing technologies with substantial scientific and engineering challenges.

“We’ve had a lot of people be supportive of us at Penn State — people in the Office of Technology Management, people in the Startup Leadership Network, Penn State alumni, the list goes on,” Zarzar said. “There’s a lot of entrepreneurial infrastructure being developed at the University and people reaching out who have been really necessary and supportive in helping to get us this far.”

About the Office of Entrepreneurship and Commercialization 

A strategic unit of the Office of the Senior Vice President for Research, the Office of Entrepreneurship and Commercialization leads Penn State’s entrepreneurship and economic development programs, including management of the University’s startup portfolio, development of programs for the LaunchBox/innovation hub network, and administration of the Invent Penn State initiative.

To view more Penn State technologies in development, visit IPNavigator.psu.edu. To view more Penn State-affiliated startups, visit StartupNavigator.psu.edu.