New toilet coating could provide cleaner flushing

Researchers from Penn State University has announced a new toilet coating that could make flushing toilets cleaner and reduce the amount of water used for toilet flushing. The team says that every day more than 141 billion liters of water is used for flushing toilets alone. The team has developed a robust, bio-inspired, liquid, sludge, and bacteria-repellant coating that can make a toilet self-cleaning.

The coating that the team has developed is called the liquid-entrenched smooth surface or LESS coating. It is a two-step spray that, among other applications, can be applied to a ceramic toilet bowl. The first spray is created from molecularly grafted polymers and is the initial step in building a smooth and liquid repellent foundation.

After it dries, the spray grows molecules that look like litter hairs with a diameter about a million times thinner than a human hair. The second spray infuses a thin layer of lubricant around the nanoscopic hairs to create a super slippery surface. The team sprayed a toilet with the two-step process in the lab and then dumped synthetic fecal matter on it.

The researchers say that the synthetic matter slides down, and nothing sticks to the toilet. This coating allows the toilets to dispose of waste with a fraction of the water needed before. The team says that the coating could last for about 500 flushes before reapplication of the lubricant layer is required.

The LESS coating takes about five minutes to cure. The team also found that the coating repelled bacteria, particularly those that spread disease and produce odors. The team is working with support from several agencies, including the Office of Naval Research, to bring the LESS coating to market.