PPG Industries and iGlass Projects Pty. Ltd. of Australia are developing dimmable glazing for automotive sunroofs that will enable drivers to adjust their car roof glass from clear to opaque, or anywhere in between.

The glazing comprises iGlass polymer dispersed liquid crystal (PDLC) switchable thin film, which offers rapid light transmission switching and excellent optical clarity, sandwiched between two plies of special PPG glass.

The result is a car roof with excellent thermal and optical performance as well as high durability and reliability, according to Dick Heilman, PPG strategic marketing director for automotive glass.

"This new glass product offers drivers the capability to switch electrically from a clear transparent view to an opaque surface, providing privacy and sun protection to occupants and objects within the vehicle," Heilman said. "By combining the iGlass switchable film with Sungate or GL-20 solar control glass by PPG, we have created an attractive product for the automotive market."

PPG will market the glass for sunroof applications in new vehicles as well as the aftermarket, but it can also be used in glazing areas such as rear quarter-windows or rear truck windows, Heilman said.

"We are very excited about working with PPG to introduce this technology to the automotive sunroof market," said Johnny Pak, chief executive officer, iGlass. "We have already had success with thin film use for switchable architectural glass products, in commercial and residential windows as well as interior room partition walls, and we look forward to expanding its applications."

iGlass Projects is an Australian manufacturer of switchable liquid crystal films for the automotive and architectural markets. The company has revolutionized the electronic glass market, with newly developed manufacturing techniques, groundbreaking technologies and a price-performance curve that makes switchable glass affordable.

Pittsburgh-based PPG is a global supplier of paints, coatings, chemicals, optical products, specialty materials, glass and fiber glass, and reported 2006 sales of $11 billion.