Fashioning Safe Choices in Fabric Dyes

At the Department of Chemical and Biochemical Engineering and under the direction of research team-lead Nina Shapley, associate professor in the department, environmentally sustainable fabric dyes are among the next wave of innovation at Rutgers engineering.

Jane Palmer, a Los Angeles textile designer, has a passion for using natural and environmentally friendly dyes to color fabrics. During the last six years, she’s gained a loyal following among high-end boutique clothing and housewares designers.

Her sights, however, are set much higher—to move mass-market fabric dyeing away from its polluting and energy consuming ways. One of Palmer’s first steps in the quest has been to work with a Rutgers engineering professor with no background or experience with dye chemistry.

Nina Shapley, an associate professor of Chemical and Biochemical Engineering, had just started working with colleagues on a project to protect molecules sensitive to ultraviolet light damage. Their test molecule was beta carotene, a natural bright-orange substance used in food dyes.

“Jane saw one of our papers and she contacted us,” Shapley said. “She was looking for potential new technologies to take her natural dye work to the next level.”

Palmer values the colors that natural dyes bring to her fabrics—sometimes vibrant, other times subtle. But natural dyes have drawbacks that make them unsuitable for mass-market fabrics: they are expensive and they fade in sunlight or when washed. The major clothing labels have looked at natural dyes but have yet to embrace them.

Change is on the horizon, however. Clothing manufacturers use billions of gallons of boiling water to dye their fabric, and it’s hard to remove dye residue from wastewater. A New York Times story in 2013 illustrated the harm of clothing manufacture in regulation-lax Bangladesh where a river glowed purple.

“It’s a health risk to the aquatic system, the environment, the general population,” Palmer said.

Just as the major labels have chosen, or have been forced, to address products made with sweatshop labor, they now need to drive environmentally sensitive and sustainable dyeing techniques. Palmer has discussed the issue with Patagonia, North Face, Nike, and others.

Shapley and Palmer secured a $225,000 National Science Foundation (NSF) grant at the beginning of 2016 to move natural-dye technology toward commercial viability.

“It’s more like applied research,” Shapley said. “Other projects I’ve worked on are very fundamental. So it’s exciting to see something with a shorter time line.”

The two are experimenting with room-temperature methods to cut the energy required to heat dye baths and are looking into low- or no-water methods to apply dye. Rather than boiling fabric in dye, they’re investigating whether finishing equipment that now applies softeners or coatings could also be used in the dyeing process.

“We need to fit into the factory because it’s already set up, and not require owners to purchase new equipment for our process,” Palmer said.

They have started by looking at the color black, which is used in 30 to 40 percent of textiles sold for apparel and home furnishings. They are trying a plant-based agricultural byproduct to form the color.

The investigators find that their different backgrounds—Palmer with a master’s degree in fine arts and Shapley with a doctorate in chemical engineering—are complementary.

“I love working with Nina because she’s really creative,” Palmer said. “She’s very open to ideas. We come from different approaches, but we’re open-minded about our ideas. So, it’s fun.”

“Jane already knew so much about dye chemistry and did so much literature-searching herself,” Shapley said. “So it’s easy for us to talk about these things. We’re both on the same wavelength. But this project is moving into a new area for both of us. We’re learning a lot of new things that we hadn’t explored.”

Their grant is from the NSF’s Small Business Innovation Research / Small Business Technology Transfer program, which seeks to transform scientific discovery into societal and economic benefit. The women are currently in the program’s first phase, a one-year proof-of-concept grant. If successful, they will apply for a second-phase development grant to directly commercialize their concepts.