An Ohio judge last week dismissed St. Louis-based Solutia's patent infringement suit against Chinese company Sinorgchem and South Korean Kumho Petrochemical.

The chemical company's Flexsys subsidiary alleged that the Chinese chemical manufacturer had copied its patented, environmentally friendly method of producing a chemical used as an anti-degradant for rubber products, namely tires.

The suit, filed five years ago in the Northern Ohio U.S. District Court, sought to keep the Chinese company, which manufactures a similar chemical used by Kumho to make tires, from using a similar process to Solutia's, keeping it from infringing on its market share. It was put on hold as the company pursued its claim before the International Trade Commission, which also ruled in favor of Sinorgchem and Kumho.

Solutia has fared better at keeping competitors from encroaching on its manufacturing processes in other countries. It won similar suits this year in Germany, China and South Korea. Solutia is "evaluating options" for an appeal, spokeswoman Melissa Zona said.

"Our intellectual property rights are extremely important, which is why we continue to defend and enforce those rights," she said.

The ruling is a blow to a company that emerged from Chapter 11 bankruptcy in February 2008 and last year derived most of its profit from the division that includes its Flexsys subsidiary. That division, which makes specialty chemicals, reported $261 million in profit for 2009, compared with $171 million in profit for its Saflex and CPFilms divisions.

At the end of last year, Solutia employed about 3,400 people worldwide, half in the U.S.