Paper manufacturing inevitably produces lignin that is a black liquid substance as a by-product. Wood chips contain lignin for 20-30%, and paper companies utilize it as fuel for their boilers. With the sluggish sales of paper products, paper companies are exploring new applications for lignin. Kanematsu that is a general trading company and Daio Paper that is a paper company will put the technology to produce carbon fines by sintering and drying lignin to practical use toward 2014. The carbon fine made in this way is highly adhesive, and it can increase the strength of the tire should it be mixed in tire. It can replace carbon black made of oil or coal that is widely used at present.
Currently, carbon black is contained in a tire for 25% in a weight ratio, and its domestic demand is about 900,000 tons a year. The two companies plan to get sales of 20 billion yen annually by replacing carbon black by carbon fines. Daio Paper built an experiment plant with a monthly production capacity of 5-10 kg of carbon fines and started to ship samples to tire manufacturers and paint makers. Kanematsu will increase customers, while Daio Paper will develop the technology for mass production. As reported in No. 526, Bridgestone is developing biomass-derived tires in alliance with Ajinomoto to follow Michelin of France and Goodyear of the U.S. Kanematsu and Daio Paper are trying to make tires more environmentally friendly in a different approach.