Exhibit 99.1

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ISP                                                                     NEWS

INTERNATIONAL SPECIALTY PRDUCTS
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       INTERNATIONAL SPECIALTY HOLDINGS AND ITS SUBSIDIARIES COMMENCE CASH
         TENDER OFFERS AND CONSENT SOLICITATIONS FOR OUTSTANDING NOTES


NEW YORK - January 19, 2006 - International Specialty Holdings Inc. ("Holdings")
and ISP Chemco Inc. ("Chemco"), ISP Chemicals Inc., ISP Minerals Inc. and ISP
Technologies Inc. (the "Chemco Purchasers" and, together with Holdings, the
"Purchasers") announced today that each of Holdings and the Chemco Purchasers
has respectively commenced cash tender offers to purchase all of the outstanding
$200,000,000 in aggregate principal amount of the 10.625% Senior Secured Notes
due 2009 issued by Holdings (the "Holdings Notes") and all of the outstanding
$405,000,000 in aggregate principal amount of the 10.25% Senior Subordinated
Notes due 2011 issued by the Chemco Purchasers (the "Chemco Notes"), as well as
related consent solicitations to amend the indentures governing each of the
Holdings Notes and the Chemco Notes. The tender offers, as well as the related
consent solicitations, are being made upon the terms and subject to the
conditions set forth in the Purchasers' Offer to Purchase and Consent
Solicitation Statement dated January 19, 2006. Each tender offer is scheduled to
expire at 9:00 a.m., New York City time, on February 16, 2006, unless extended
or earlier terminated.

         The total consideration to be paid in cash for each $1,000 principal
amount of validly tendered Holdings Notes, subject to the terms and conditions
of the tender offer and consent solicitation, will be a fixed price of $1,055.63
which includes a $2.50 consent payment for holders who tender their Holdings
Notes and deliver their related consents on or prior to 5 p.m., New York City
time, on February 1, 2006 (unless extended or earlier terminated).

         The total consideration to be paid in cash for each $1,000 principal
amount of validly tendered Chemco Notes, subject to the terms and conditions of
the tender offer and consent solicitation, will be based on a fixed spread of 50
basis points over the 2.75% U.S. Treasury Note due June 30, 2006. This total
consideration includes a $10.00 consent payment for holders who tender their
Chemco Notes and deliver their related consents on or prior to 5 p.m., New York
City time, on February 1, 2006 (unless extended or earlier terminated).

         In addition, holders of each of the Holdings Notes and the Chemco Notes
who validly tender their Notes and whose Notes are accepted for payment will be
eligible to receive accrued and unpaid interest up to, but not including, the
payment date.

         In conjunction with the offers to purchase, the Purchasers are
soliciting consents to eliminate substantially all of the restrictive covenants
and certain of the events of default contained in the respective indentures
governing the Holdings Notes and Chemco Notes, as well as modify or eliminate
certain other provisions contained in the indentures. Adoption of the proposed
amendments requires the consent of holders of at least a majority of the
aggregate principal amount of each series of Notes. Holders must validly tender
their Notes and deliver their consents on or prior to 5 p.m., New York City
time, on February 1, 2006 (unless extended or earlier terminated) in order to


receive the applicable consent payment. Holders tendering Notes after such date
will not be eligible to receive the applicable consent payment.

         The tender offer is conditioned upon, among other things, the
Purchasers receiving the requisite consents from each series of Notes and
certain of the Chemco Purchasers entering into a new senior secured credit
facility in an amount sufficient to pay, among other things, the consideration
for all validly tendered Holdings Notes and Chemco Notes. In connection with the
consummation of the tender offers and entering into this new credit facility,
Holdings intends to contribute to Chemco its Synthetic Elastomers division. We
refer you to the filings made by Holdings with the U.S. Securities and Exchange
Commission for more information with respect to the Synthetic Elastomers
divisions.

         The Purchasers have retained UBS Securities LLC and Bear, Stearns & Co.
Inc. to act as Dealer Managers in connection with the tender offer. Questions
about the tender offer may be directed to the Liability Management Group of UBS
Securities LLC at (888) 722-9555 x4210 (toll free), the Global Liability
Management Group of Bear, Stearns & Co. Inc. at (877) 696-2327 (toll free), or
to D.F. King & Co., the Information Agent for the tender offers and consent
solicitations, at (212) 269-5550 (collect) or (800) 628-8536 (toll free).

         A more comprehensive description of the tender offers and consent
solicitations can be found in the Purchasers' Offer to Purchase and Consent
Solicitation Statement and the related Letters of Transmittal dated January 19,
2006. Copies of these documents and other related documents can be obtained from
the Information Agent.

         This press release is neither an offer to purchase nor a solicitation
of an offer to sell securities and no recommendation is made as to whether or
not holders of the Holdings Notes and Chemco Notes should tender their
securities pursuant to the tender offers. The tender offers are made only by the
Offer to Purchase and Consent Solicitation Statement dated January 19, 2006.

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International Specialty Products Inc. ("ISP"), the parent company of
International Specialty Holdings Inc. and ISP Chemco Inc., is a leading
multinational manufacturer of specialty chemicals, industrial chemicals,
synthetic elastomers and mineral products. ISP sells over 400 specialty and
industrial chemicals and synthetic elastomer and minerals products to
approximately 6,000 customers from a variety of industries in over 90 countries.
ISP's headquarters is located in Wayne, New Jersey, USA.

This press release may contain "forward-looking statements" within the meaning
of the federal securities laws and, as such, concerns matters that are not
historical facts. These statements are subject to risks and uncertainties that
could cause the actual results to differ materially from those expressed in such
statements. Important factors that could cause such differences are discussed in
the filings made by International Specialty Holdings Inc. and ISP Chemco Inc.
with the U.S. Securities and Exchange Commission and are incorporated herein by
reference.


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