<PAGE>   1
TRIDENT, INC.
1114 Federal Road
Brookfield, CT 06804
203/740-9333



August 7, 1996


Mr. Donald J. Polak
President & CEO
Porelon Group
1480 Gould Drive
Cookeville, TN  38506

Dear Don:

        Reference is made to the Memorandum of Understanding (the "Memorandum")
between Trident, Inc. ("Trident") and Micropore, Inc., ("Micropore") pursuant to
which Trident agreed to purchase from Micropore, and Micropore agreed to supply
to Trident, certain inks through 1998. This letter sets forth the agreement of
Trident and Micropore hereinafter known as the Porelon Group ("Porelon") to
terminate the Memorandum and enter into new arrangements for the purchase and
supply of inks under the following terms and conditions:

         1. Purchase of Inks. Trident agrees, during the term of this Letter
Agreement (and any extension thereof), to purchase all of its requirements for
its XXXXXXXX, XXXXX, XXXXXXXXXX, XXXX inks (individually, an "Ink," and
collectively, the "Inks") from Porelon. The Inks purchased shall be manufactured
by Porelon in accordance with the confidential specifications and quality
standards previously supplied to Porelon by Trident, with such reasonable
modifications as Trident may request from time to time.

         2. Price and Method of Payment. Trident shall purchase Inks from
Porelon at the prices set forth on Schedule A hereto. The prices so set forth
shall be subject to change by Porelon with ninety (90) days notice. Any price
adjustment must maintain the same ratio between standard cost and selling price
as now exists and Trident shall have the right to require evidence of cost
increases prior to agreement of such price adjustment. Payment for Inks sold by
Porelon to Trident shall be made within thirty (30) days of delivery and
acceptance of such Inks by Trident. In the event that Trident fails to pay for
any shipment of Inks within such thirty (30) day period, Porelon shall
thereafter have the right to apply a reasonable finance charge to any unpaid
balance not to exceed 1.5% per month.

        3. Obligation to Supply. Porelon may terminate its obligation to supply
any or all of the Inks identified in Paragraph 1 to Trident with 180 days
notice. Notice not to supply one ink does not affect Porelon's obligation to
supply the other inks.
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         4. Delivery of Inks. Trident shall place orders for Inks in amounts
greater than 380 lbs. per order and at least sixty (60) days in advance of any
requested delivery date. Porelon shall ship all Inks F.O.B., Cookeville,
Tennessee4. Acceptance or rejection of any shipment shall be made by Trident
within the longer of fourteen (14) calendar or ten 10 business days of receipt
of such shipment by Trident. Porelon acknowledges that time of delivery of the
Inks is of the essence. In the event that Porelon fails to deliver Inks (or any
portion thereof) by the requested delivery date, and Porelon fails to cure such
failure within thirty (30) days, Trident shall have the right to terminate this
Letter Agreement by written notice to Porelon and seek alternative sources for
the Inks.

         5. Further Assurances. Porelon acknowledges that it may be difficult
for Trident to locate alternative sources for the Inks in the event of a failure
by Porelon to deliver any Ink in such volume and in accordance with such
specifications as Trident may require. Porelon therefore agrees that, during the
term of this Letter Agreement (and any extension thereof), it will maintain an
alternative facility capable of producing the Inks within ten (10) business days
in the event that any circumstances arise which make the production of Inks (in
such volumes, and in accordance with such quality standards, as required by
Trident) at its current facilities impossible or impracticable. Porelon shall
provide Trident with reasonable assurances of the existence and capability of
such alternative facility, including physical inspection by Trident, if
requested, prior to September 15, 1996. In the event that, at any time, Trident
reasonably concludes that such alternative facility is not or will not be
capable of meeting its requirements for Inks, and Porelon does not correct the
deficiencies in 30 days, Trident shall have the right to terminate this Letter
Agreement by written notice to Porelon and seek alternative sources for the
Inks.

         6. Term and Termination. Subject to the early termination provisions
set forth above, the terms and conditions of this Letter Agreement shall
continue until December 31, 2000 (the "Termination Date"); provided, however,
that the term of this Letter Agreement shall be extended automatically for a
period of one year commencing on the Termination Date and on each subsequent
anniversary of the Termination Date unless either party has given the other
party written notice, at least ninety (90) days prior to any such extension
date, of such party's election not to extend the term of this Letter Agreement.

         7. Confidentiality and Non-Competition. At all times during and after
the term of this Letter Agreement, Porelon shall keep confidential all
proprietary and technical information provided to it by Trident (whether
pursuant to this Letter Agreement or otherwise) with respect to any Inks, ink
jet printheads or any related equipment or materials and shall not disclose or
use in any way any such information. In recognition of the confidential
information provided to it hereunder (and in related documents), Porelon agrees
that until the date which is two (2) years from the earlier of (a) the
Termination Date, or (b) the date on which this Letter Agreement is otherwise
terminated, it will not engage, directly or indirectly, in the sale of any ink
jet inks to, or the manufacture of ink jet inks for sale by, current or future
users, original equipment manufacturer customers, or distributors of any ink jet
devices sold by Trident during such period or any suppliers thereof.
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         8. Conflicting Agreements and Remedies. In the event of any conflict
between the terms of this Letter Agreement and any other document or agreement
between the parties (including the Nonexclusive License Agreement and Assignment
and License Back Agreement, as both are appended to the Memorandum), the terms
of this Letter Agreement shall control. In the event of a breach of this Letter
Agreement by either party, the party who has not breached shall be entitled to
equitable relief in addition to any other remedies available to it.

         9. Assignment. This Letter Agreement shall inure to the benefit of and
be binding upon the parties hereto and their respective successors and assigns,
provided that Porelon may only assign its rights or obligations hereunder to a
successor entity by way of merger, consolidation or the sale of all or
substantially all of its business and assets, which successor entity expressly
agrees to assume Porelon's obligations under this Letter Agreement and any
related agreements or documents.

         10. Governing Law and Severability. The terms of this Letter Agreement
shall be governed by and construed in accordance with the internal laws, and not
the laws pertaining to conflicts of laws, of the State of Connecticut. Should
any provision of this Letter Agreement now or at any time during its term (or
any extension thereof) conflict with any applicable law or regulation, said
provision shall be considered as of no force and effect and the remainder of
this Letter Agreement shall remain in full force and effect.

         11. Waiver. The failure of either party to enforce at any time or for
any period of time the provisions hereof (or of a purchase order) in accordance
with their terms will not be construed to be a waiver of such provisions or of
the right of such party thereafter to enforce each and every such provision.

        12. Effective Date. This Letter Agreement shall be effective as of
August 1, 1996.
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         If the above accurately sets forth our understanding, please so
indicate by executing this Letter Agreement where provided below and returning
it to me.

         Sincerely,

                                  TRIDENT, INC.

                                  By: /s/ ELAINE A PULLEN
                                     ________________________________________

                                     Elaine A. Pullen
                                     President and Chief Executive Officer



        ACCEPTED AND AGREED TO:

        PORELON, INC.

        By: /s/ DONALD J. POLAK
           _________________________________________
           Donald J. Polak
           President & Chief Executive Officer
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                                   SCHEDULE A
                                    THE INKS
<TABLE>
<CAPTION>

        NAME                             TRIDENT PART NO.                    PRICE / LB.
        ----                             ----------------                    -----------
<S>                                      <C>                         <C>           <C>
        XXXXXXXX                         XXX-XXXX-XX                 $             X.XX
        XXXXX                            XXX-XXXX-XX                 $             X.XX
        XXXXXXXXXX                       XXX-XXXX-XX                 $             X.XX
        XXXXXXXXXX                       XXX-XXXX-XX                 $             X.XX
        XXXX                             XXX-XXXX-XX                 $             X.XX
</TABLE>