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                                                                       EXHIBIT 7

                      [ADFLEX SOLUTIONS, INC. LETTERHEAD]

                            NON-DISCLOSURE AGREEMENT

     ADFLEX SOLUTIONS, INC., Chandler, Arizona, and INNOVEX, INC. hereby agree
that the following terms and conditions shall govern confidential information
disclosed during discussions between the two companies and any of their agents.
As used herein, "ADFlex" means ADFlex Solutions, Inc. and all subsidiaries and
other companies owned or controlled by it as well as any predecessor company
including Rogers Corporation, and any company or business acquired by ADFlex
Solutions, Inc. during the term of this Agreement.

1. All information disclosed by ADFlex or derived therefrom by Innovex, Inc.
   shall be and remain the property of ADFlex.

2. Innovex, Inc. shall use the information for the above-stated purpose only and
   shall not disclose the information or any part thereof to any other person,
   firm or corporation, and shall, further, restrict circulation of the
   information within its own organization except to the extent necessary to
   fulfill the above-stated purpose. The obligations of this Paragraph (2) shall
   not apply to the extent that any of the information (a) is or becomes part of
   the public domain through no fault of Innovex, Inc., (b) is rightfully known
   to Innovex, Inc. prior to the disclosure by ADFlex, as established by written
   records, (c) is subsequently rightfully received by Innovex, Inc. from a
   third party, and (d) can be shown by written documentation to have been
   developed independently of ADFlex's information.

3. All documents, drawings, photographs, sketches, designs, and formulations
   furnished by ADFlex shall remain the property of ADFlex and shall be returned
   to ADFlex promptly at its request, together with all copies made thereof.

4. Innovex, Inc. agrees that any samples provided by ADFlex to Innovex, Inc. are
   for evaluation purposes only and that no effort will be made to analyze such
   samples or to determine their composition or method of manufacture. Innovex,
   Inc. further agrees to return all samples to ADFlex upon request upon the
   completion of such evaluation.

5. ADFlex personnel are not authorized to receive information in confidence.
   Innovex, Inc. shall not disclose any trade secrets or proprietary information
   to ADFlex, and except as may hereafter be agreed in writing, all
   communication from Innovex, Inc. to ADFlex shall be made on a
   non-confidential basis.

6. This Agreement shall be applicable to all exchanges of information concerning
   the above subject, except as may hereafter be agreed to in writing, and shall
   be effective as of the execution date below.

7. The normal term of this Agreement shall be two (2) years from the date of
   execution, but the obligations provided for herein shall remain in force for
   a period of ten (10) years from the date of disclosure.

8. This Agreement may be terminated by either party upon 15 days written notice
   to the other, but such termination shall not affect any obligations imposed
   hereunder with respect to any previously disclosed information.
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Non-Disclosure Agreement
Page

IN WITNESS WHEREOF, the parties have caused this Agreement to be executed as of
the 30th day of April, 1999.

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<S>                                             <C>
INNOVEX, INC                                    ADFLEX SOLUTIONS, INC.

By: /s/ WILLIAM P. MURNANE
    ----------------------------------------    By: /s/ NEIL DIAL
                                                ----------------------------------------
                                                Neil Dial

Title: President
      --------------------------------------    Title: President and Chief Operating Officer
                                                --------------------------------------

Date: May 3, 1999
      --------------------------------------    Date: April 29, 1999
                                                --------------------------------------
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