WILMINGTON, DE, APRIL 10, 2007 . . . Hercules Incorporated (NYSE: HPC) today announced the following schedule and teleconference information for its first quarter earnings release and teleconference:

Preliminary Earnings (in conjunction with Annual Meeting):  April 19, 2007 – Before the stock market opens.

Annual Shareholders Meeting:  April 19, 2007 – 11:00 a.m. (Eastern).

Earnings Release:  April 30, 2007 – After the stock market closes.

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

Teleconference:  May 1, 2007 — 9:00 a.m. (Eastern).

Dial in Number:  973-582-2750 – Ask for Conference ID # 8679973
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 Information.

Web Replay:  Will be available beginning at noon on May 1, 2007 on the web at www.herc.com, under Shareholder Information.

 # # #

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.