WARRENVILLE, Ill. — Beginning this month, IC Corporation will raise its bus prices an estimated 4 to 5 percent.

Company officials said the rising costs of copper, platinum, aluminum and palladium facilitated the need to increase bus prices.

Michael Cancelliere, vice president and general manager of IC Corporation, said that while the company doesn't have ultimate control over the increase in worldwide commodity costs, it can offset some of the increase through its own manufacturing process.

"We continue making improvements to be as efficient as possible in our production facilities in Conway, Ark., and Tulsa, Okla., so that we don’t pass the full effect of the commodity increases on to our customers," Cancelliere said. "Our pledge has been and will continue to be that IC Corporation will work aggressively to keep costs in line for our customers as much as possible."

A large percentage of a bus' material value consists of palladium and copper products, and the prices for these commodities have increased substantially — nearly 70 percent — over the last two years. Steel and aluminum prices have risen 10 percent and more than 30 percent, respectively.

The price of platinum, which is used in new 2007 emissions aftertreatment devices, has jumped recently as well.