Campus & Beyond Bird-of-Paradise Feathers Inspire Darkest Fabric Ever Made Stories You May Like Cornellian Crossword: ‘Spirit of Zinck’s’ President Emerita Honored With ‘Pollack Plaza’ The Engineering Quad’s Iconic Sundial Marries Art and Science With help from the Lab of Ornithology, a doctoral alum who’s a Human Ecology prof developed a novel shade of ‘ultrablack’ Editor’s note: This story was adapted from a feature in the Cornell Chronicle. By Tom Fleischman The color “ultrablack”—defined as reflecting less than 0.5% of the light that hits it—has a variety of uses, including in cameras, solar panels, and telescopes, but it’s difficult to produce and can appear less black when viewed at an angle. Now, a Cornell lab led by a doctoral alum has devised a simple method for making the elusive color. Taking cues from nature—in particular the striking black of the magnificent riflebird—researchers in Human Ecology’s Responsive Apparel Design (RAD) Lab dyed a white merino wool knit fabric with polydopamine, followed by etching of the material in a plasma chamber to create nanofibrils—spiky nanoscale growths. Paul Maury / Lab of OrnithologyThe magnificent riflebird. These features were made to mimic the light-trapping capabilities found on the riflebird’s ultrablack feathers, which absorb most of the light that hits them. The researchers’ two-step approach produced the darkest fabric currently reported; it’s also easy to manufacture, scalable, wearable, and not angle-dependent. The researchers’ two-step approach produced the darkest fabric currently reported; it’s also easy to manufacture, scalable, wearable, and not angle-dependent. They have applied for patent protection with the Cornell Center for Technology Licensing and hope to form a company around their process, which can be used on natural materials, including wool, silk, and cotton. “From a design perspective, I think it’s exciting because a lot of the ultrablack that exists isn’t really as wearable as ours,” says Larissa Shepherd, PhD ’17, assistant professor in the Department of Human Centered Design. “And it stays ultrablack even from wider angles.” Shepherd, the RAD Lab’s director, is senior author of “Ultrablack Wool Textiles Inspired by Hierarchical Avian Structure,” which was published in Nature Communications in November. Shepherd’s co-authors are doctoral students Hansadi Jayamaha and Kyuin Park, MS ’23, both RAD Lab members. Their work included analysis of feathers from the riflebird, a member of the bird-of-paradise family found in New Guinea and Australia. Shepherd and her team obtained riflebird feathers from the Cornell Lab of Ornithology with the help of Mary Ferraro, bird collections manager, and Vanya Rohwer, curator of birds and mammals. Prof. Larissa Shepherd, PhD ’17, in the lab. The riflebird’s striking black plumage comes from melanin pigment combined with tightly bunched barbules that serve to deflect light inward, absorbing nearly all of it. This renders the bird extraordinarily black, but only when viewed straight on; at an angle, its plumage appears shiny. This same coloration is evident in other creatures, including fish and butterflies. Shepherd says her group’s choice of polydopamine for their dye was intentional. Stories You May Like Cornellian Crossword: ‘Spirit of Zinck’s’ President Emerita Honored With ‘Pollack Plaza’ “Polydopamine is a synthetic melanin, and melanin is what these creatures have,” she says. “And the riflebird has these really interesting hierarchical structures, the barbules, along with the melanin. So we wanted to combine those aspects in a textile.” The ultrablack dye in the RAD Lab. It wasn’t enough to simply coat the surface of the wool: the researchers had to have the polydopamine penetrate into the fibers of the fabric, so every bit of it became black. That’s because the plasma etching process removes some surface material of the outermost fibers, leaving behind spiky nanofibrils, which are a key component. “The light basically bounces back and forth between the fibrils, instead of reflecting back out,” Jayamaha says. “That’s what creates the ultrablack effect.” The light basically bounces back and forth between the fibrils, instead of reflecting back out—that’s what creates the ultrablack effect. Fiber science PhD candidate Hansadi Jayamaha Analysis revealed that the group’s fabric had an average total reflectance of 0.13%, making it the darkest fabric yet reported. And it remained ultrablack across a 120-degree angular span, meaning it appears the same at up to a 60-degree angle from either side or straight on, superior to currently available commercial materials. According to Park, their ultrablack fabric has potential in many solar thermal applications, converting and utilizing absorbed light into thermal energy. “We could actually use the ultrablack fabric for thermo-regulating camouflage,” he says. Lab member Hansadi Jayamaha with a sample of dyed fabric. In fall 2024, fashion design management major Zoe Alvarez ’25 created a black strapless dress inspired by the riflebird that incorporated as its centerpiece ultrablack material with a splash of iridescent blue. Images of the dress were used to confirm ultrablack’s true “blackness”: when the image’s contrast, hue, vibrance, or brightness were adjusted, all the other colors changed, but ultrablack remained the same. Top: A prototype dress, incorporating the ultrablack fabric, designed by Zoe Alvarez ’25. (All photos by Ryan Young / Cornell University, unless otherwise indicated.) Published December 2, 2025 Leave a Comment Cancel replyOnce your comment is approved, your email address will not be published. Required fields are marked *Comment * Name * Class Year Email * Save my name, email, and class year in this browser for the next time I comment. Δ Other stories You may like Campus & Beyond The ‘Morris Worm’: A Notorious Chapter of the Internet’s Infancy Quizzes & Puzzles It’s Your Jam: Test Your Knowledge with a Big Red Music Quiz Alumni Tribute to Europe’s Lost Synagogues Is an Artist’s Labor of Love