PPG Industries' optical and specialty materials segment saw its sales drop by 6 percent to $314 million in the first quarter of this year, reflecting a return to a more traditional seasonal sales pattern and somewhat lower consumption in the U.S. PPG noted that the first quarter of 2012 had been particularly strong because some clients were recovering then from the autumn 2011 floods in Thailand. Thai Optical was probably one of them. On the other hand, sales grew in Europe because of the successful introduction of Generation VII Transitions lenses in February. Modest improvements in the demand for silica also helped the turnover. The segment's operating profit declined by 9 percent to €99 million. PPG's management declined to comment on the discussions with Essilor over the future ownership of Transitions. Across its numerous business units, PPG posted flat sales of $3.3 billion for the quarter and a rise in adjusted net income to $235 million from $216 million in the year-ago period.