Chemtura Corp., Philadelphia, said it is raising prices for some of its chemical products because of "significant and sustained" increases in the cost of key raw materials it uses.

The price hikes of up to 15 percent will be effective Jan. 1.

"These increases are essential to sustain Chemtura as a viable supplier and to enable continued reinvestment," the company said.

The increases will be imposed on products from its antioxidant and UV stabilizer business. UV stabilizers are used to slow degradation of products from exposure to ultraviolet radiation in sunlight.

Chemtura, a maker of specialty chemicals. emerged from bankruptcy protection in November.    - Paul Schweizer