SIDNEY, OHIO -- A rebound in the North American automotive market is leading Mitsui Chemicals Inc. and Prime Polymer Co. Ltd. to increase the size of a planned compounding expansion at a plant in Sidney, Ohio.

The change will add about 30 million pounds of polypropylene compound capacity to a 60 million pound expansion that the firms had announced in May. The expansion will take place at a plant operated by Advanced Composites Inc., a joint venture between the two Tokyo-based firms. The new capacity should come online in the second half of 2013, giving the Sidney plant just over 590 million pounds of annual capacity.

"Although the North American automobile industry was negatively impacted by the global financial crisis, currently the market has returned to normalcy with forecasts of significant growth in the future," officials with Mitsui and Prime Polymer said in a Jan. 17 news release.

North American auto builds totaled almost 15 million last year after bottoming out at less than 9 million in 2009 as a recession hit the market. Many vehicles also now have more plastic content, as carmakers seek lightweight to meet mileage standards.

Mitsui and Prime Polymer previously announced a 55 million pound PP compound capacity addition at an Advanced Composites plant in Aguascalientes, Mexico, that will be up and running by the end of 2013. In May, Prime expanded its compounding holdings by acquiring a majority stake in Brazilian compounder Produmaster Industria e Comercio Ltda.

Mitsui owns 65 percent of Prime Polymer, which operates almost 3 billion pounds of annual PP capacity and 1.5 billion pounds of annual polyethylene capacity.