Exhibit 99.1

FOR IMMEDIATE RELEASE

Koppers Announces Proposed Private Offering of $300 Million Senior Notes due 2019

PITTSBURGH, November 12, 2009 – Koppers Inc., a subsidiary of Koppers Holdings Inc. (NYSE:KOP), today announced that it is proposing an offering through a private placement of $300 million aggregate principal amount of unsecured senior notes due 2019 (the “Notes”). It is expected that the Notes will be guaranteed by Koppers Holdings Inc. and certain of Koppers Inc.’s domestic subsidiaries. The net proceeds of this offering are intended to be used to repay outstanding debt, pay related fees and expenses and for general corporate purposes.

The Notes and the related guarantees are being offered by the initial purchasers only to qualified institutional buyers in reliance on Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”) or, outside the United States, to persons other than “U.S. persons” in compliance with Regulation S under the Securities Act. The Notes and the related guarantees have not been registered under the Securities Act or the securities laws of any other jurisdiction and may not be offered or sold in the United States absent registration or an applicable exemption from, or in a transaction not subject to, registration requirements. A confidential offering circular will be made available to eligible holders. The offering will be conducted in accordance with the terms and subject to the conditions set forth in the offering circular.

This press release shall not constitute an offer to sell, or the solicitation of an offer to buy, any securities, nor shall there be any sales of securities mentioned in this press release in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

Safe Harbor Statement

Certain statements in this press release are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 and may include, but are not limited to, statements about sales levels, restructuring, profitability and anticipated expenses and cash outflows. All forward-looking statements involve risks and uncertainties. All statements contained herein that are not clearly historical in nature are forward-looking, and words such as “believe,” “anticipate,” “expect,” “estimate,” “may,” “will,” “should,” “continue,” “plans,” “intends,” “likely,” or other similar words or phrases are generally intended to identify forward-looking statements. Any forward-looking statement contained herein, in other press releases, written statements or documents filed with the Securities and Exchange Commission, or in Koppers

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communications with and discussions with investors and analysts in the normal course of business through meetings, phone calls and conference calls, regarding expectations with respect to sales, earnings, cash flows, operating efficiencies, product introduction or expansion, the benefits of acquisitions and divestitures or other matters as well as financings and repurchases of debt or equity securities, are subject to known and unknown risks, uncertainties and contingencies. Many of these risks, uncertainties and contingencies are beyond our control, and may cause actual results, performance or achievements to differ materially from anticipated results, performance or achievements. Factors that might affect such forward-looking statements, include, among other things, general economic and business conditions, demand for Koppers goods and services, competitive conditions, interest rate and foreign currency rate fluctuations, availability of key raw materials and unfavorable resolution of claims against us, as well as those discussed more fully elsewhere in this release and in documents filed with the Securities and Exchange Commission by Koppers, particularly our latest annual report on Form 10-K and quarterly report on Form 10-Q. Any forward-looking statements in this release speak only as of the date of this release, and we undertake no obligation to update any forward-looking statement to reflect events or circumstances after that date or to reflect the occurrence of unanticipated events.

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