The University of Georgia Research Foundation Inc. and the University of Puerto Rico have granted an international, non-exclusive license for a portfolio of glow-in-the-dark pigments that can be designed to emit light in any color of the visible spectrum for nearly a day. Performance Indicator LLC of Lowell, Mass., acquired the license.
Phosphorescence is a process in which energy absorbed by a substance is released relatively slowly in the form of light. Some materials release energy over long periods of time and are known as long-persistence phosphors. But scientists have puzzled over how to produce long-persistent phosphors that glow blue and green, red or other long-wavelength colors, or white.
By exploiting the phenomenon of energy transfer, the UGARF/UPR technology can produce long-lasting glow in any color, including blue, green or red, and in tints and hues, such as pink-red with white-without extensive modification to the composition of the materials.
The seven phosphors included in this patent portfolio are simple to manufacture and environmentally safe. They do not contain sulfur, radioactive materials, lead or other potentially harmful materials.
They can be used in a multitude of consumer and industrial applications, including signage, special paints and in combination with polymers for the manufacture of many items, such as color-coded electric wiring, insulation, textiles, novelty items and printing ink.
The phosphors were developed under the guidance of the late William Yen, a professor of physics at UGA. Yen was a pioneer in the field of long-persistence phosphorescence. Co-inventors are Weiya Jia, presently vice president of Performance Indicator, and Xiao-Jun Wang, associate professor of physics, Georgia Southern University. Yen and Jia pioneered the field of long-persistence phosphorescence and developed the first systematic approach to customize the color and duration of glow.
“Phosphorescent pigments are an important industrial segment. The U.S. color pigment industry was estimated to be around $2.5 billion a year in 2005 with projected growth around 6 percent until 2009. The phosphor segment may represent as much as 5 percent to 7 percent of this market,” said Gennaro Gama, a senior technology manager with UGARF in charge of licensing the portfolio. “This agreement represents a completely new and untapped business opportunity for UGARF and UGA’s new generation of researchers working in this field.”
