WILMINGTON, DE, JUNE 22, 2007 . . . Hercules Incorporated (NYSE: HPC) today announced the following schedule and teleconference information for its second quarter earnings release and teleconference:

Earnings Release: July 23, 2007 – After the stock market closes.

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

Teleconference: July 24, 2007 — 10:00 a.m. (Eastern).

Dial in Number: 973-935-8511 – Ask for Conference ID # 8957494
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 July 24, 2007 on the
web at www.herc.com, under Shareholder Information.

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