Even if soy sauce, ketchup, or engine oil gets on a white shirt, a rinse with water makes it clean. That is because the fabric has a self-cleaning coating that blocks stains. Shorter wash times greatly reduce water and electricity use. If commercialized, it is expected to save resources and also significantly cut microplastic pollution from the washing process.
A research team led by Wang Dayang, a chemistry professor at Jilin University in China, said it developed a spray-on fabric coating that allows clothes to be washed with only water and published the findings in Communications Chemistry, a Nature journal, on the 209th. The team said the anti-stain coating can be applied to both natural and synthetic fibers and can reduce water and energy consumption in laundering by more than 80%.
◇Polymer layer repels grease
The researchers created a kind of protective barrier on fabric with two polymer materials. Spraying positively charged polydadmac (PDADMAC) and negatively charged polyvinylsulfonic acid (PVSA) alternately draws them together to form a strong polymer layer.
The polymer layer formed on the fabric has a high density of hydroxyl groups (-OH), each composed of one hydrogen and one oxygen atom, making it highly hydrophilic. When a soiled fabric is rinsed, the hydroxyl groups in the polymer layer form strong hydrogen bonds with water. A thin water film then forms between the fiber surface and the grease. When grease cannot penetrate the fiber and remains floating in water, a light rinse is enough to make the garment clean.
The team said tests on three materials—cotton, silk, and polyester—showed performance equal to or better than conventional washing in removing various stains such as soy sauce, engine oil, perilla oil, vinegar, and ketchup. On ordinary cotton fabric, most grease remains after rinsing with only water, but with the self-cleaning coating, cleaning efficiency exceeded 90%, the researchers said.
A conventional washing machine washes by agitating clothes with water and detergent, then rinsing several times and spinning. Clothes with a self-cleaning coating are finished by simply rinsing with water, without detergent. That cuts water and electricity use and shortens wash time. Compared with a typical cycle of one wash and four rinses, the team estimated that each wash can reduce consumption of water, electricity, and time by more than 80%.
◇Likely cost-effective, with environmental benefits
The researchers also tested whether the self-cleaning coating affects humans or the environment. When cowpea plants were grown with water used to rinse the clothes and with regular tap water, there was no difference in growth. Tests of the self-cleaning coating on mouse skin cells also showed no issues. The self-cleaning coating delivered the same laundering effect in hard water rich in minerals, such as groundwater or spring water, as in tap water. Ordinary detergents do not foam well in hard water, which greatly reduces washing performance.
Of course, coating fabric with a polymer layer that blocks contamination incurs additional costs. However, the team estimated that depending on the detergent type, the initial coating cost is offset after 15 to 50 washes. Given that one person does at least 100 washes a year, the self-cleaning coating can be considered sufficiently economical. The researchers said the self-cleaning coating did not degrade even after more than 100 washes.
Considering the environmental protection benefits, the payoff could be immediate. Surfactants, the ingredients that separate grease in detergents, are a main cause of water pollution. Surfactants do not readily break down in nature. When they flow into rivers, they form a foam film that blocks sunlight and oxygen. Washing with only water, without detergent, can prevent such problems. Domestic wastewater treatment also becomes simpler. The researchers noted that rinsing with water alone significantly reduces the amount of microplastics released from synthetic fibers.
◇Self-cleaning fabrics inspired by lotus leaves
Nature also has a well-known example that resists dirt: the lotus. Although it lives in muddy water, its leaves are spotless. In 1997, Wilhelm Barthlott, a botanist at the University of Bonn, discovered that microscopic protrusions on lotus leaves prevent water droplets from soaking in and instead make them roll off. In the process, dust on the surface is washed away.
The micro-protrusions on lotus leaves are covered with a waxy layer that repels water. Air pockets between the protrusions block other substances from entering. As a result, droplets containing contaminants cannot enter between the protrusions and hang at the tips, then fall off with slight movement. Scientists call this the "lotus effect."
Schoeller Textil, a Swiss textile company, developed NanoSpher technology in 2001, creating a fine corrugated structure on fabric surfaces inspired by the lotus leaf. Several sports apparel companies sell waterproof and stain-repellent products made with this technology. Like lotus leaves, when beverages or ketchup spill on clothing, they slide along the surface before staining.
Oil does not respond to the lotus effect. That is because the protrusion surfaces on lotus leaves are covered with a waxy layer that is oleophilic. In 2008, a team led by Gareth McKinley, a mechanical engineering professor at the Massachusetts Institute of Technology (MIT), reported in the Proceedings of the National Academy of Sciences (PNAS) a micro-protrusion structure that even oil cannot penetrate. The team calculated the optimal spacing to maintain an air layer between the micro-protrusions. When the gaps were narrower than those of lotus leaves, even oil dropped from a height did not soak in and fell off like water droplets.
The micro-protrusion structure of lotus leaves is also vulnerable to impact. Heavy rain can damage the self-cleaning function. The Wyss Institute for Biologically Inspired Engineering at Harvard University found an answer in the pitcher plant, which uses sticky secretions to make insects slip inward.
In 2014, the researchers reported in Nanotechnology a fabric treated with SLIPS, the English acronym for "slippery liquid-infused porous surface." A lubricating liquid was applied to the protrusion surfaces to let contaminants slide off. Kim Pil-seok, then at the Wyss Institute and now chief technology officer of SK Innovation and head of the Environmental Science and Technology Institute, was a co-author of the paper.
Self-cleaning apparel is expensive. That is because creating microstructures on fabric surfaces costs a lot. For now, it is sold only in niche markets such as high-performance sportswear and outdoor gear. But as microplastics shed from clothing have emerged as a serious environmental issue, interest in self-cleaning technology is growing. Lotus leaves and pitcher plants may soon appear frequently in apparel advertisements.
References
Communications Chemistry (2026), DOI: https://doi.org/10.1038/s42004-026-01942-7
Nanotechnology (2014), DOI: https://doi.org/10.1088/0957-4484/25/1/014019
PNAS (2008), DOI: https://doi.org/10.1073/pnas.0804872105