Invented in China during 105 AD, paper has contributed a lot in the development of our civilization. For centuries, it’s been the most popular medium of conveying information. Paper can portray our thoughts physically, through hard copy.
With the growing demand, mass production of paper has led to environmental problems. More paper means more cutting down of trees for pulp extraction. To deal with this issue a group of researchers at the University of California, Riverside, along with Wenshou Wang of Shandong University in China invented reprintable paper.
Reprintable paper is a recent invention made to solve the environmental problems caused by the mass production of regular paper. It’s developed with a coating that doesn’t require ink to write and can be printed on, erased and reused more than 80 times.
Printing is done with light and nanoparticles that coat the paper. The nanoparticles are between 1 and 100 nanometres in size (i.e., 100,000 times thinner than an average piece of paper). Each nanoparticle gets energy from light and causes the other particle to change colour.
The coating is the ‘magic ingredient’ of reprintable paper. Two types of nanoparticles are used for coating, that change from clear to visible and vice versa when exposed to light.
The first type of nanoparticle is Prussian blue that appears blue and turns colourless when extra electrons are supplied. The other nanoparticle is titanium dioxide that supplies the additional electrons when exposed to UV (ultraviolet) light.
This is the secret behind the reprintability of this revolutionary paper. The printing is done through a laser beam. Erasing is done by heating the paper.
Scientists at Xerox Corporation have invented a reusable paper whose prints last only for a day. This makes the paper reusable, thus significantly reducing paper consumption.
The technology behind reusable paper comes from the development of compounds that change colour when exposed to a specific wavelength of light. The printed matter disappears in about 16 to 24 hours.
Reusable paper is currently part of a laboratory project and may soon curb the amount of paper waste.
Our society is becoming paperless by relying more on online technology. But, paper still plays a crucial role as printed materials have demonstrated that they can establish a strong emotional connection in marketing efforts. The introduction of reprintable and reusable paper for commercial purposes can save natural resources. This new reprintable paper can solve many problems and provide an alternative to the production of traditional paper.