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                                                                   EXHIBIT 10(p)


                              SEVENTH AMENDMENT TO
                                CREDIT AGREEMENT



         THIS SEVENTH AMENDMENT ("Amendment") dated as of September 29, 2000, by
and among the borrowers listed on Schedule 1 (collectively "Companies") and
Comerica Bank, a Michigan banking corporation ("Bank").

                                    RECITALS:

         A.   Companies and Bank entered into a Credit Agreement dated as of
 June 13, 1996, which was amended by six amendments (as amended, "Agreement").

         B.   Companies and Bank desire to amend the Agreement as hereinafter
 set forth.

         NOW, THEREFORE, the parties agree as follows:

         1.   The definition of "Lending Availability" set forth in Section 1
of the Agreement is amended to read in its entirety as follows:

          "`Lending Availability' shall mean as of any date of determination
          thereof, the sum of (a) eighty five percent (85%) of Eligible
          Accounts plus (b) thirty five percent (35%) of Eligible
          Inventory; provided, however, in no event shall the amount of
          Lending Availability determined under this clause (b) exceed Four
          Million Dollars ($4,000,000)."

          2.   Section 2.A.2 of the Agreement is amended to read in its entirety
               as follows:


          "(a) From the date of execution of this Agreement to the Revolving
               Credit Maturity Date, the Companies shall pay to the Bank a
               Revolving Credit Commitment Fee monthly in arrears commencing
               June 1, 1996, and within three Business Days after the last day
               of each month thereafter. The Revolving Credit Commitment Fee
               shall be an amount equal to the average daily balance of the
               unborrowed portion of the Revolving Credit Commitment for the
               monthly period then ending, minus the average daily face amount
               of any outstanding Letters of Credit during such period,
               multiplied by one half of one percent (1/2%). The Revolving
               Credit Commitment Fee shall be computed on the basis of a year of
               three hundred sixty (360) days and assessed for the actual number
               of days elapsed. Upon request of Companies, Bank shall provide to
               Companies the detail of Bank's computation of the Revolving
               Credit Commitment Fee. Whenever any payment of the Revolving
               Credit Commitment Fee shall be due



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               on a day which is not a Business Day, the date for payment
               thereof shall be extended to the next Business Day;

         3.    The first three sentences of Section 4.1 of the Agreement are
 amended to read in their entirety as follows:

               "The Revolving Credit Notes and the Advances under Section 2
         hereof shall bear interest from the date thereof on the unpaid
         principal balance thereof from time to time outstanding, at a rate per
         annum equal to one quarter of one percent (1/4%) plus the Prime Rate.
         Interest shall be payable monthly on the first Business Day of each
         calendar month, commencing on the first Business Day of the calendar
         month during which such Advance is made, and at maturity.
         Notwithstanding the foregoing, from and after the occurrence of any
         Event of Default and during the continuation thereof, the Advances
         shall bear interest, payable on demand, at a rate per annum equal to
         three and three quarters percent (3-1/4%) above the Prime Rate."

         4.    Companies hereby represent and warrant that, after giving effect
to the amendments contained herein, (a) execution, delivery and performance of
this Amendment and any other documents and instruments required under this
Amendment or the Agreement are within each Company's corporate powers, have been
duly authorized, are not in contravention of law or the terms of any Company's
Articles of Incorporation or Bylaws, and do not require the consent or approval
of any governmental body, agency, or authority; and this Amendment and any other
documents and instruments required under this Amendment or the Agreement, will
be valid and binding in accordance with their terms; (b) the continuing
representations and warranties of each Company set forth in Sections 7.1 through
7.15 of the Agreement are true and correct on and as of the date hereof with the
same force and effect as made on and as of the date hereof; (c) the continuing
representations and warranties of each Company set forth in Section 7.16 of the
Agreement are true and correct as of the date hereof with respect to the most
recent financial statements furnished to the Bank by Companies in accordance
with Section 10.1 of the Agreement; and (d) no Event of Default (as defined in
the Agreement) or condition or event which, with the giving of notice or the
running of time, or both, would constitute an Event of Default under the
Agreement, has occurred and is continuing as of the date hereof.

          5.   Except as expressly provided herein, all of the terms and
conditions of the Agreement remain unchanged and in full force and effect.

          6.   This Amendment shall be effective upon the sale of the assets of
Seibert-Oxidermo as consented to by Bank.




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         IN WITNESS the due execution hereof as of the day and year first above
written.


COMERICA BANK                            DETREX CORPORATION

By:                                         By:
    --------------------------------------     ---------------------------------
                                                   Gerald J. Israel

Its: Assistant Vice President               Its:   Vice President-Finance and
                                                   Chief Financial Officer


                                            THE ELCO CORPORATION

                                            By:
                                               ---------------------------------
                                                   Gerald J. Israel
                                            Its:   Treasurer

                                            HARVEL PLASTICS, INC.

                                            By:
                                               ---------------------------------
                                                   Gerald J. Israel
                                            Its:   Director

                                            SEIBERT-OXIDERMO, INC.

                                            By:
                                               ---------------------------------
                                                   Gerald J. Israel
                                            Its:   Treasurer





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                                   SCHEDULE 1




Detrex Corporation

The Elco Corporation

Harvel Plastics, Inc.

Seibert-Oxidermo, Inc.


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