Exhibit 99.1


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CONTACTS:
Investors:    William Kuser       (203) 573-2213
Media:        Mary Ann Dunnell    (203) 573-3034

CROMPTON TO OFFER SENIOR NOTES

MIDDLEBURY, CONN., JULY 21, 2004 - Crompton Corporation (NYSE:CK) today
announced that it is planning to offer approximately $600 million aggregate
principal amount of senior notes.

The company intends to use the net proceeds to (i) repay outstanding borrowings
under its existing domestic revolving credit facility, (ii) fund its concurrent
tender offer and consent solicitation for its 8.50% Senior Notes due 2005 and
6.125% Senior Notes due 2006, including tender premiums, consent payments, and
accrued and unpaid interest, and (iii) fund working capital and general
corporate purposes.

The new senior notes will be offered in a combination of:
   o Senior Notes due 2011;
   o Senior Notes due 2014; and
   o Senior Floating Rate Notes due 2010.

The offering is part of a refinancing that includes the replacement of
Crompton's credit facility with a new revolving credit facility in a principal
amount of up to $250 million, with a minimum principal amount of $200 million.
The closing of the new credit facility, the offering of the notes, and the
consent solicitation and tender offer are conditioned on the completion of one
another. Each transaction also is subject to market and other customary
conditions.

The senior notes will be offered in the United States to qualified institutional
buyers pursuant to Rule 144A under the Securities Act of 1933, as amended, and
outside the United States pursuant to Regulation S under the Securities Act. The
notes have not been registered under the Securities Act and may not be offered
or sold in the United States without registration or an applicable exemption
from the registration requirements.

THIS PRESS RELEASE IS NEITHER AN OFFER TO SELL NOR THE SOLICITATION OF AN OFFER
TO BUY THE NOTES OR ANY OTHER SECURITIES, AND SHALL NOT CONSTITUTE AN OFFER,
SOLICITATION OR SALE IN ANY JURISDICTION IN WHICH SUCH AN OFFER, SOLICITATION OR
SALE IS UNLAWFUL. ANY OFFERS OF THE NOTES WILL BE MADE ONLY BY MEANS OF A
PRIVATE OFFERING MEMORANDUM.



Crompton Corporation, with annual sales of $2.2 billion, is a producer and
marketer of specialty chemicals and polymer products and equipment. Additional
information concerning Crompton Corporation is available at
www.cromptoncorp.com.

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FORWARD-LOOKING STATEMENTS
Certain statements made in this release are forward-looking statements that
involve risks and uncertainties, including, but not limited to, general economic
conditions, the outcome and timing of antitrust investigations and related civil
lawsuits to which Crompton is subject, the ability to obtain selling price
increases, the ability to obtain and timing of new financing, pension and other
post-retirement benefit plan assumptions, energy and raw material prices and
availability, production capacity, changes in interest rates and foreign
currency exchange rates, changes in technology, market demand and customer
requirements, the enactment of more stringent environmental laws and
regulations, the ability to realize expected cost savings under Crompton's cost
reduction initiatives, the amount of any additional earn-out payments from GE,
and other risks and uncertainties detailed in Crompton's filings with the
Securities and Exchange Commission. These statements are based on Crompton's
estimates and assumptions and on currently available information. The
forward-looking statements include information concerning our possible or
assumed future results of operations, and Crompton's actual results may differ
significantly from the results discussed. Forward-looking information is
intended to reflect opinions as of the date this release was issued and such
information will not necessarily be updated by Crompton.