Feb 23, 2011. /Lesprom Network/. Due to the ongoing cost pressure on energy, chemicals and other ram materials, Koehler Paper Group announces a price increase for its thermal papers in Europe, effective with April 1 shipments by 5%. With a turnover of Euro 540 million and sales of 429,000 tons of paper, the Koehler Group is one of the few independent German companies in the paper industry.