Jul 22, 2011. /Lesprom Network/. Nippon Paper to raise white duplex board, printing paper and wrapping paper prices by 10%, effective September 21, as the company said in a press release received by Lesprom Network. Amid an upward trend in the price of raw materials and fuels, Nippon Paper has made sustained efforts to reduce costs. However, it has proven difficult to absorb all the cost increases through the Company's own efforts, and it was decided that there was no alternative but to pass a portion of the cost on to the product price, the company said.