SCHEDULE 14A INFORMATION
                PROXY STATEMENT PURSUANT TO SECTION 14(a) OF
                    THE SECURITIES EXCHANGE ACT OF 1934

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   |X|  Soliciting Material Pursuant to Rule 14a-12

                             DEXTER CORPORATION
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              (Name of Registrant as Specified In Its Charter)

                                    N/A
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  (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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                        As filed with the Commission on May 18, 2000


                     [Letterhead of Dexter Corporation]





                                          May 17, 2000



Dear Fellow Shareholder:

      I would like to update you on a number of important developments that
have occurred at Dexter Corporation over the last few months.

      As you know on February 25, 2000, the Dexter Board of Directors
authorized management and our financial advisors, Lehman Brothers Inc., to
explore all strategic alternatives available for Dexter to maximize
shareholder value in the short term. The Board of Directors authorized this
action in response to International Specialty Products Inc.'s unilateral
attempt to seize control of your company by waging a proxy contest and
proposing to acquire your company in a negotiated merger transaction which
at that time was unfinanced and purported to offer $45.00 per share in
cash. By virtue of the sale process we have instituted, we have succeeded
in causing ISP to increase the price of its proposal to $50.00 per share
and to obtain a financing commitment from The Chase Manhattan Bank to
finance its proposal. Nonetheless, we continue to believe that ISP's
proposal is quite conditional and does not reflect the full value inherent
in Dexter Corporation including its 75% ownership position in Life
Technologies, Inc.

      As a result, your Board of Directors has authorized management to
take the following important actions:

      >>    Continue our effort to sell Dexter Corporation in a single
            transaction. The parties that expressed interest in acquiring
            all of Dexter are principally life sciences companies that were
            interested in acquiring your company in a tax-free stock merger
            transaction. Unfortunately, the decline in the public equity
            markets since March has adversely affected the trading prices
            of their equity securities and, accordingly, the value of the
            consideration they offered. Nonetheless, we believe there is
            strong continuing interest in a transaction involving all of
            Dexter, as well as in a separate and independent acquisition of
            Life Technologies.


      >>    Pursue the sale of the individual Dexter businesses. At the end
            of the initial stage of our sale process, we received a number
            of significant indications of interest for Dexter's wholly
            owned businesses -- Nonwoven Materials, Electronic Materials
            and Adhesive & Coating Systems. We are engaging in discussions
            with these bidders in order to firm up their indications of
            interest. We currently believe that values in excess of $50.00
            per share may be achievable from this process of disaggregating
            the business segments of our company.

      >>    Provide ISP with acceptable forms of acquisition agreements for
            both Dexter Corporation and Life Technologies. On April 20,
            2000, ISP, in connection with its proposal to acquire Dexter at
            $50.00 per share plus one contingent value right (which
            purports to allow Dexter's shareholders to participate in the
            proceeds from a subsequent sale by ISP of Dexter's shares in
            Life Technologies under certain circumstances), submitted to us
            its proposed changes to our form of acquisition agreement for
            Dexter. We had also provided to ISP a form of agreement to
            acquire the remaining publicly traded minority shares of Life
            Technologies. ISP declined to submit a proposal to acquire the
            Life Technologies minority. Our legal advisors, Skadden, Arps,
            Slate, Meagher & Flom LLP, discussed with ISP's legal advisors
            the changes to the proposed form of acquisition agreement,
            focusing specifically on those changes that created uncertainty
            for our shareholders that ISP's proposed acquisition would
            close -- promptly and upon the terms agreed by the parties.
            Similarly, they discussed the conditional nature of the
            commitment letter from The Chase Manhattan Bank.

            We have sent to ISP a revised form of acquisition agreement for
            Dexter Corporation and for Life Technologies taking into
            account those changes from ISP that we believed reasonable
            under the circumstances. More significantly, we have told ISP
            that we are prepared to enter into an acquisition transaction
            with them, largely on the terms and conditions they have
            requested, if they insert into our forms of agreement a price
            for Dexter and a price for Life Technologies that represents a
            full and fair value for the shareholders of each company.

      We are pursuing this three-pronged course of action at this time
because we believe that all opportunities should be explored
simultaneously. It is only at the end of this process that we can ensure
you will have received the best available transaction.

      Please understand that we have no interest in delay and are working
expeditiously to create for you the very best transaction available --
whether it's a transaction with ISP or with other purchasers of the
individual Dexter businesses. Our only interest is ensuring that you
receive the highest value for your shares as promptly as possible.

      We appreciate the support you have shown us during this difficult
time.


                                 Sincerely,



                                 K. Grahame Walker
                                 Chairman and Chief Executive Officer


Note -- We are required to include with all communications regarding our
program to maximize value for our stockholders the following cautionary
statement -- "No assurance can be given that shareholder value will be
maximized."

Information regarding persons who may be considered "participants" in the
solicitation of proxies from Dexter shareholders can be found in Dexter's
preliminary proxy statement on Schedule 14A filed with the Securities and
Exchange Commission. Investors and security holders are advised to read the
definitive proxy statement that will be filed by Dexter relating to
Dexter's 2000 annual meeting, when it becomes available, because it will
contain important information. Security holders may obtain a free copy of
the definitive proxy statement (when available) and the preliminary proxy
statement on Schedule 14A containing the participant information referred
to above and other documents filed by Dexter with the Commission at the
Commission's web site at http://www.sec.gov. The definitive proxy
statement, the Schedule 14A containing the participant information and such
other documents may also be obtained for free from Dexter Corporation by
directing such request to: Dexter Corporation, One Elm Street, Windsor
Locks, Connecticut 06096, Attention: Investor Relations, 860-292-7675.
Copies can also be obtained from: Mackenzie Partners, Inc. 156 fifth
Avenue, New York, N.Y. 10010, telephone: 800-322-2885, facsimile:
212-929-0308 or proxy@mackenziepartners.com.