WILMINGTON, DE, APRIL 13, 2006 . . . Hercules Incorporated (NYSE: HPC) today announced the following schedule and teleconference information for its first quarter earnings release and teleconference:

Earnings Release: April 26, 2006 – After the stock market closes.

Distribution: By Business Wire and Hercules' website at www.herc.com.

Teleconference: April 27, 2006 — 8:00 a.m. (Eastern)

Dial in Number: 973-582-2734 — Ask for Conference ID #7284954
Please call 5-10 minutes before the scheduled start of the teleconference.

Webcast: Listen-only mode via Internet broadcast from Hercules
website at www.herc.com, under Shareholder Info.

Web Replay: Will be available mid-morning on April 27, 2006
on the web at www.herc.com, under Shareholder Info.

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Hercules manufactures and markets chemical specialties globally for making a variety of products for home, office and industrial markets. For more information, visit the Hercules website at www.herc.com.