Reusable Paper Using Ultraviolet Light

Scientists are redefining what it means to go paperless.

Researchers at the University of California, Riverside, have been working on an alternative to traditional paper that can be printed on and erased more than 20 times. Its low-cost production could help reduce waste, deforestation, and chemical pollution, according to chemistry professor Yadong Yin, who copublished a paper on the design in Nature.

“If we are comparing the rewritable paper to conventional ones, it has the advantages of being more economical, environmental, and energy friendly,” he said. “It can be produced at about the same cost as regular paper and does not require additional inks for printing.”

Ultraviolet light is used to print on the rewritable “paper,” which is a thin plastic film coated in nontoxic dye. Heat it up to 115 degrees Celsius, and the text will disappear.

The material doesn’t disintegrate over time, but the scientists are working on a method to create a cellulose-based version that’s less environmentally harmful to produce than regular paper. They want to increase the number of uses to at least 200 to lower costs even more.

Despite growing reliance on technology, people use 69 million tons of paper and paperboard each year in the United States alone; only a third is produced from recycled paper. That’s taking a toll on the planet, which loses 12 to 15 million hectares of forests—the size of about 36 football fields—per minute. Deforestation reduces biodiversity and accounts for 15 percent of global greenhouse gases. Not to mention that it takes 3.4 gallons of water to make just one sheet of paper. As for ink and toner, when they dry on paper they release volatile organic compounds into the air. VOCs produce environmentally harmful ozone particles and chronic exposure causes health problems in humans, including liver and kidney damage.

The scientists expect the rewritable paper to go into commercial production in a few years.

“We’re working on developing a printer that can use UV light to directly write text and pictures on the rewritable paper,” said Yin. To do that, laser printers could be modified by removing the toner and other parts. In the future, said Yin, a user could just “print out a newspaper, read it, and then put the paper back to print new content.”