Koppers Holdings said higher prices and strong demand for its carbon materials and chemicals pushed first-quarter sales up by 13 percent to $348 million, from $309 million a year ago.

Net income jumped to $13.2 million, or 63 cents per share, beating analysts' estimates of $11.6 million, or 54 cents per share.

Sales fell for Koppers' railroad crossties and utility poles but Chief Executive Walter Turner said he expects demand for those products to improve later this year. He also is optimistic about 2009 results when Koppers expects to be operating two joint ventures in China.