Exhibit (a)(1)(C)

                          NOTICE OF GUARANTEED DELIVERY
                                       FOR
                        TENDER OF SHARES OF COMMON STOCK
                  (INCLUDING THE ASSOCIATED RIGHTS TO PURCHASE
                      FRACTIONAL UNITS OF PREFERRED STOCK)

                                       OF
                               DEXTER CORPORATION

                                       TO

                             ISP ACQUISITION CORP.,
                       AN INDIRECT WHOLLY-OWNED SUBSIDIARY
                                       OF
                      INTERNATIONAL SPECIALTY PRODUCTS INC.
                    (NOT TO BE USED FOR SIGNATURE GUARANTEES)

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         THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT,
                  NEW YORK CITY TIME, ON MONDAY, JULY 24, 2000,
                         UNLESS THE OFFER IS EXTENDED.
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           This Notice of Guaranteed Delivery, or a form substantially
equivalent hereto, must be used to accept the Offer (as defined below) if
certificates representing shares of common stock, par value $1.00 per share (the
"Common Stock"), including the associated rights to purchase fractional units of
Preferred Stock (the "Rights" and, together with the Common Stock, the
"Shares"), issued pursuant to the Rights Agreement (as defined in the Offer to
Purchase) of Dexter Corporation, a Connecticut corporation ("Dexter"), are not
immediately available, if the procedure for book-entry transfer cannot be
completed prior to the Expiration Date (as defined in Section 1 of the Offer to
Purchase), or if time will not permit all required documents to reach the
Depositary prior to the Expiration Date. Such form may be delivered by hand,
transmitted by facsimile transmission or mailed to the Depositary. See Section 3
of the Offer to Purchase.

                        THE DEPOSITARY FOR THE OFFER IS:
                            WILMINGTON TRUST COMPANY


                                                                                                
                 By Mail:                              By Facsimile Transmission:                  By Hand/Overnight Delivery:

        Corporate Trust Operations                  (For Eligible Institutions Only)                 Wilmington Trust Company
         Wilmington Trust Company                            (302) 651-1079                         1105 North Market Street,
               P.O. Box 8861                                                                               First Floor
      Wilmington, Delaware 19885-9472                Confirm Facsimile By Telephone:                Wilmington, Delaware 19801
(registered or certified mail recommended)                   (302) 651-8869                      Attn: Corporate Trust Operations



           DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER
THAN AS SET FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA FACSIMILE TO A
NUMBER OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY.

           This form is not to be used to guarantee signatures. If a signature
on a Letter of Transmittal is required to be guaranteed by an "Eligible
Institution" under the instructions thereto, such signature guarantee must
appear in the applicable space provided in the signature box on the Letter of
Transmittal.

           The Eligible Institution that completes this form must communicate
the guarantee to the Depositary and must deliver the Letter of Transmittal and
certificates for Shares to the Depositary within the time period shown herein.
Failure to do so could result in a financial loss to such Eligible Institution.

              THE GUARANTEE ON THE REVERSE SIDE MUST BE COMPLETED.


NY2:\921980\04\JR#K04!.DOC\54104.0016

Ladies and Gentlemen:

           The undersigned hereby tenders to ISP Acquisition Corp., a Delaware
corporation ("Purchaser") and indirect wholly-owned subsidiary of International
Specialty Products Inc., a Delaware corporation ("ISP"), upon the terms and
subject to the conditions set forth in Purchaser's Offer to Purchase, dated June
26, 2000 (the "Offer to Purchase"), and the related Letter of Transmittal
(which, together with any amendments or supplements thereto, constitute the
"Offer"), receipt of which is hereby acknowledged, the number of shares set
forth below of common stock, par value $1.00 per share (the "Common Stock"),
including the associated rights to purchase fractional units of Preferred Stock
issued pursuant to the Rights Agreement (as defined in the Offer to Purchase)
(the "Rights" and, together with the Common Stock, the "Shares"), of Dexter
Corporation, a Connecticut corporation ("Dexter"), pursuant to the guaranteed
delivery procedures set forth in Section 3 of the Offer to Purchase.




                                                                     
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Number of Shares:                                                       Name(s) of Record Holder(s):
                 ---------------------------------------------


                                                                                                  PLEASE PRINT
Certificate Nos. (if available):
                                                                        Address(es):


                                                                                                                       ZIP CODE
Check box if Shares will be tendered by book-entry                      Area Code and Tel. No.:
transfer:


                                                                        Signature(s):
Account Number:
Dated:                                                  , 2000
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                                       2

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                                    GUARANTEE
                    (NOT TO BE USED FOR SIGNATURE GUARANTEES)

           The undersigned, a firm which is a bank, broker, dealer, credit
union, savings association or other entity which is a member in good standing of
a recognized Medallion Program approved by the Securities Transfer Association
Inc., including the Securities Transfer Agents Medallion Program, the Stock
Exchange Medallion Program and the New York Stock Exchange Medallion Signature
Program or any other "eligible guarantor institution" (as such term is defined
under Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended),
guarantees to deliver to the Depositary either certificates representing the
Shares tendered hereby, in proper form for transfer, or confirmation of
book-entry transfer of such Shares into the Depositary's account at The
Depository Trust Company, in each case with delivery of a properly completed and
duly executed Letter of Transmittal (or facsimile thereof), with any required
signature guarantees, or an Agent's Message, and any other documents required by
the Letter of Transmittal, within three trading days (as defined in the Offer to
Purchase) after the date hereof.

           The Eligible Institution that completes this form must communicate
the guarantee to the Depositary and must deliver the Letter of Transmittal and
certificates for Shares to the Depositary within the same time period herein.
Failure to do so could result in a financial loss to such Eligible Institution.


                                                                    

Name of Firm:
                                                                                             AUTHORIZED SIGNATURE

Address:                                                                Name:
        ------------------------------------------------------
                                                                                                  PLEASE PRINT

                                                                        Title:
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                                                     ZIP CODE

Area Code & Tel. No:                                          Date:                                               , 2000
                    --------------------------------               -----------------------------------------------




DO NOT SEND CERTIFICATES FOR SHARES WITH THIS NOTICE.  CERTIFICATES SHOULD BE
SENT ONLY WITH YOUR LETTER OF TRANSMITTAL.

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