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                                                                   Exhibit 4.6

















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                              AMENDMENT TO CREDIT AGREEMENT
                              -----------------------------

         This Amendment to the Credit Agreement is executed as of this 28th day 
of February, between Chemi-Trol Chemical Co., an Ohio Corporation ("Borrower") 
and The Fifth Third Bank of Northwestern Ohio, N.A. ("Bank").

         The parties executed an Amended and Restated Credit Agreement dated 
as of May 2, 1996, ("the Credit Agreement") whereby Bank agreed to make 
Revolving Loans to Borrower up to an amount of fifteen million dollars 
($15,000,000) through May 1, 1997.

         NOW THEREFORE, in consideration of the parties agreement to amend the
Credit Agreement, the premises and covenants herein, and other good and valuable
consideration, the receipt and sufficiency of which are acknowledged, the
parties agree to amend the Credit Agreement as follows:

         1.       Section 5.11, FINANCIAL LEVELS AND RATIOS, of the credit
                  agreement is hereby amended to read, Borrower shall maintain
                  and end each fiscal year with the following financial levels
                  and ratios; (a) Debt to Worth not to exceed 1.8:1; Minimum
                  Tangible Net Worth of not less than $18,500,000, Working
                  Capital of not less than $13,000,000 after reducing current
                  liabilities by the balloon payment, associated with Mortgage
                  Note #756086-52019 due October 1, 1997; and a Current Ratio
                  adjusted for the balloon payment associated with Mortgage Note
                  #756086-52019 due October 1, 1997, of not less than 1.5:1.

         Except as specifically amended herein, all the terms and provisions of
the Credit Agreement shall remain in full force and in effect through the
termination date.

         Executed as of the date first written above.


CHEMI-TROL CHEMICALS CO.              FIFTH THIRD BANK OF
                                      NORTHWESTERN OHIO, N.A.
                                      
By: /s/ Robert W. Woolf, President    By: /s/ Jeffrey C. Shrader, Vice President
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By: /s/ Kevin D. Lauck, Secretary                                         
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