By Victoria Stilwell DuPont Co. (DD) filed a lawsuit in Oregon against Heraeus Materials Technology LLC and its customer, SolarWorld Industries America Inc., alleging the two companies infringed on a patent recently issued to DuPont related to solar cell technology. DuPont claims Heraeus and SolarWorld violated the diversified U.S. manufacturer's patent on front-side metallization paste materials by making, selling or using Heraeus's front-side silver pastes. The lawsuit follows a continuing patent infringement suit DuPont filed against Heraeus in September, also related to the solar cell technology materials. In that case, DuPont alleged Heraeus's H94XX series and H92XX series front-side silver pastes infringe DuPont's Solamet photovoltaic metallization paste, thick film materials used in the construction of both crystalline silicon and thin film solar cells. DuPont has received a boost from higher pricing in recent quarters, offsetting raw material expenses. DuPont reported in April its first-quarter profit rose 4% as the company benefited from higher pricing and a jump in sales of agricultural products, as well as strong growth in developing markets. Shares of DuPont closed Wednesday at $51.04 and were inactive in premarket trade. The stock is up 11% so far this year. Write to Victoria Stilwell at Victoria.Stilwell@dowjones.com
