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                                                                    EXHIBIT 10.2



                               REPAYMENT AGREEMENT

         AGREEMENT made as of the 23rd day of March, 1999, by and between
Advanced Deposition Technologies, Inc., a Delaware corporation (ADTECH) and
Alexander Boxall ("Boxall"), an individual residing in Madrid Spain.

         WHEREAS, ADTECH owes a certain amount of money to Pedro Nunez Barranco
Guembe ("Guembe") under the terms of a certain promissory note; and

         WHEREAS, Boxall has agreed to guarantee the debt of ADTECH to Guembe,
in exchange for the right to convert whatever amount Boxall pays to Guembe, into
shares of the common stock, $.01 par value per share (the "Common Stock") of
ADTECH.

         NOW, THEREFORE, in consideration of the mutual covenants herein
contained and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

1.       Agreement Relating to Outstanding Debt to Guembe.
         ------------------------------------------------

         (a) ADTECH hereby agrees to use its best efforts, consistent with
prudent cash management practices and ADTECH's plan for growth, to pay all
amounts due and owing to Guembe under that certain promissory note, dated
December 20, 1997 (the "Guembe Note"), issued by ADTECH to Guembe in the
original principal amount of Nine Hundred Ninety Thousand Dollars ($990,000) on
or before December 19, 1999 (the "Maturity Date").

         (b) If ADTECH determines that it will be unable to repay the total
amount due under the Guembe Note on or prior to the Maturity Date, ADTECH shall
give written notice of such determination to Boxall at least thirty (30) days
prior to the Maturity Date and Boxall hereby agrees to pay to Guembe any
remaining amount outstanding under the Guembe Note (together with any
accumulated outstanding interest as provided in Section 1(c) below, the "Boxall
Debt"), on behalf of ADTECH, on or before the Maturity Date.

         (c) If Boxall is required to make any payment to Guembe pursuant to
Section 1(b), ADTECH hereby agrees to use its best efforts, consistent with
prudent cash management practices and ADTECH's plan for growth, to repay the
Boxall Debt on or before December 31, 2000. The Boxall Debt shall bear interest
at the thirty day London Interbank Offered Rate, plus 2%, compounded monthly,
based on such rate as of the last day of such month and shall be due and payable
on March 1, 2001 ("Boxall Debt Maturity Date"). For purposes of this Section
1(c), interest on the Boxall Debt shall begin to accrue on the date on which
Boxall makes a payment to Guembe pursuant to Section 1(b) and shall continue
until the earlier of (x) the Conversion Date (as defined below), if Boxall
elects to convert such Debt into shares of Common Stock, as provided in Section
1(d), (y) the Redemption Date (as defined below), if ADTECH elects to redeem all
of the outstanding balance of the Boxall Debt or (z) the Boxall Debt Maturity
Date.

         (d) If on January 1, 2001 (the "Conversion Date"), there exists any
outstanding balance of the Boxall Debt, Boxall shall have the right at any time
after the Conversion Date through March 1, 2001, to convert all or part of the
outstanding balance of such Debt into shares of the Common Stock at a 



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purchase price per share equal to the Fair Market Value of the Common Stock on
the Conversion Date, but in no event less than Three Dollars and Fifty cents
($3.50) per share. For purposes of this Section 1(d). "Fair Market Value" shall
mean a value equal to the average of the last reported sale price per share of
the Common Stock on the NASDAQ electronic bulletin board (or other principal
United States market on which the Common Stock is then trading) for the twenty
(20) consecutive business days ending with the last business day prior to the
Conversion Date. The certificate evidencing shares of Common Stock shall bear a
legend substantially similar to that described below in Section 1(g).

         (e) If Boxall does not exercise his conversion right as set forth in
Section 1(d), ADTECH shall have the right at any time after January 31, 2001
through March 1, 2001, to redeem all of the outstanding balance of the Boxall
Debt for shares of Common Stock based on a price per share equal to the Fair
Market Value of the Common Stock. For purposes of this Section 1(e), "Redemption
Date" shall mean the date when ADTECH redeems all of the outstanding balance of
the Boxall Debt and "Fair Market Value" shall mean a value equal to the average
of the last reported sale price per share of the Common Stock on the NASDAQ
electronic bulletin board (or other principal United States market on which the
Common Stock is then trading) for the twenty (20) consecutive business days
ending with the last business day prior to the Redemption Date. The certificate
evidencing shares of Common Stock shall bear a legend substantially similar to
that described below in Section 1(g).

         (f) If ADTECH has not paid all amounts owing to Boxall pursuant to
Section 1(c) on or prior to November 30, 2000, ADTECH and their respective
affiliates (as defined in the Securities Act of 1933, as amended) agree that
they will not buy, sell or in any way, directly or indirectly, trade shares of
Common Stock at any time during the period from December 1, 2000 to and
including March 1, 2001.

         (g) If ADTECH issues shares of Common Stock to Boxall pursuant to
Section 1(d) or 1(e) above, Boxall understands that the certificate(s) or other
instrument(s) representing such shares of Common Stock shall bear a restrictive
legend in substantially the following form (and a stop-transfer order may be
placed against transfer of such stock certificates):

LEGEND
------

                  THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
                  APPLICABLE STATE SECURITIES LAWS, THE SECURITIES HAVE BEEN
                  ACQUIRED FOR INVESTMENT AND MAY NOT BE OFFERED FOR SALE, SOLD,
                  TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE
                  REGISTRATION STATEMENT FOR THE SECURITIES UNDER THE SECURITIES
                  ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS,
                  OR AN OPINION OF COUNSEL, IN A GENERALLY ACCEPTABLE FORM. THAT
                  REGISTRATION IS NOT REQUIRED UNDER SAID ACT OR APPLICABLE
                  STATE SECURITIES LAWS OR UNLESS SOLD PURSUANT TO RULE 144
                  UNDER SAID ACT.

2. Representations and Warranties of ADTECH.
   ----------------------------------------

         As an inducement to Boxall to enter into this Agreement and to
consummate the transactions contemplated hereby, ADTECH hereby represents and
warrants to Boxall as follows:

         (a) ADTECH is a corporation duly incorporated, validly existing and in
good standing under the laws of the State of Delaware and is duly licensed or
qualified to transact business as a foreign corporation and is in good standing
in each jurisdiction in which the ownership or leasing of its assets or



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properties requires it to be so licensed or qualified, except where the failure
to be so licensed or qualified would not individually, or in the aggregate, have
a material adverse effect on the business or operations of ADTECH.

         (b) All corporate action necessary for the execution, delivery and
performance by ADTECH of this Agreement and the consummation by ADTECH of the
transactions contemplated hereby has been duly taken. This Agreement constitutes
the legal, valid and binding obligation of ADTECH enforceable against ADTECH in
accordance with its terms.

         (c) Neither the execution and delivery of this Agreement by ADTECH nor
the consummation of the transactions contemplated hereby will (i) violate,
conflict with or result in the breach or termination of, or constitute a default
under ADTECH's organizational documents or the terms of any material agreement
or instrument to which ADTECH is a party or by which ADTECH is bound or subject,
(ii) violate any judgment, order, injunction, decree or award against or binding
upon ADTECH, or (iii) constitute a violation of any applicable law or regulation
of any applicable jurisdiction.

         (d) The representations and warranties of ADTECH shall survive the
Closing.

3. Representations and Warranties of Boxall.
   ----------------------------------------

         (a) This Agreement constitutes the legal, valid and binding obligation
of Boxall enforceable against Boxall in accordance with its terms.

         (b) The representations and warranties of Boxall shall survive the
Closing.

4. Condition Precedent.
   -------------------

         The performance of the obligations undertaken by the parties herein are
subject to the closing and consummation of the transactions set forth in that
certain Exchange Agreement by and among ADTECH, Boxall and DNA Export S.A. dated
as of the date hereof.

5. Miscellaneous.
   -------------

         (a) Entire Agreement. This Agreement constitutes the entire agreement
             ----------------
of the parties hereto with respect to the subject matter hereof and supersedes
all prior agreements and undertakings, both written and oral.

         (b) Assignment. This Agreement shall not be assigned by operation of
             ----------
law or otherwise without the prior written consent of the other parties hereto.
This Agreement shall be binding upon the heirs, legatees and devisees,
executors, administrators and legal representatives of the parties, and upon the
permitted assigns of the parties.

         (c) Amendment; Waiver. This Agreement may not be amended or modified
             -----------------
except by an instrument in writing signed by the parties.

         (d) Governing Law. This Agreement shall be governed by, and construed
             -------------
in accordance with, the law of The Commonwealth of Massachusetts, without giving
effect to the conflict of law principles thereof.



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         (e) Counterparts. This Agreement may be executed in one or more
             ------------
counterparts, and by the parties hereto in separate counterparts, each of which
shall be deemed an original, but all of which together shall constitute one and
the same instrument.

         (f) Notices. All notices, consents, requests, instructions, approvals
             -------
and other communications provided for herein shall be deemed validly given, made
or served if in writing and delivered personally or sent by certified mail,
postage prepaid, or by recognized overnight courier delivery service (delivery
charges prepaid), or by telecopier:

         (i)      if to Boxall, addressed to:

                  Mr. Alexander Boxall
                  Calle Atalanta 31
                  Las Rozas
                  28230 Madrid
                  Spain
                  Telephone: 011-3491-6644060
                  Fax: 011-3491-6986293

                  with copies to:


                  Gibson, Dunn & Crutcher, LLP
                  200 Park Avenue
                  New York, New York 10166-0193
                  Attn: Ignacio Foncillas, Esq
                  Telephone: 212-351-3971
                  Fax: 212-351-4035

         (ii)     if to ADTECH, addressed to:

                  Advanced Deposition Technologies, Inc.
                  Miles Standish Industrial Park
                  Taunton, MA  02780
                  Attn.: Mr. Glenn Walters
                  Telephone: 508-823-0707
                  Fax:  508-823-4434

                  with copies to:
                  Mintz, Levin, Cohn, Ferris, Glovsky and Pope, P.C.
                  One Financial Center
                  Boston, MA  02111
                  Attn:  Doug Zingale, Esq.
                  Telephone: 617-348-1763
                  Fax:  617-542-2241

         or such other address as shall be furnished in writing by any party to
the other. Any notice (i) sent by telecopier shall be deemed delivered when
received as verified by electronic confirmation, (ii) sent by overnight courier
shall be deemed delivered when received, (iii) sent by certified mail shall be
deemed 



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delivered on the tenth day after it is sent and (iv) given personally shall be
deemed given when received; provided, however, that any notice received after
                            -----------------
5:00 p.m. or on a day that it not a business day in the place of receipt shall
be deemed delivered at the opening of business on the next business day in the
place of receipt.

         (g) Arbitration. Any claim, dispute disagreement or controversy that
arises between the Parties that relates to the performance of either Party's
duties under this Agreement for the breach of any of the terms or conditions set
forth herein, that is not solved by amicable agreement shall be resolved
exclusively by arbitration initiated in accordance with the procedures
hereinafter set forth in this Section 5(g). All arbitrations pursuant to this
Section 5(g) shall be conducted in accordance with the rules then obtaining of
the American Arbitration Association by a single arbitrator appointed by the
Parties if they shall agree upon an arbitrator within thirty (30) days of the
commencement of such arbitration or by the American Arbitration Association if
they shall fail so to agree. Unless otherwise agreed by the Parties within
thirty (30) days of the initiation of such arbitration, all arbitration
proceedings shall be held in English in the city of Boston, Massachusetts. Each
Party agrees to comply with any award made or order issued in such proceeding
that has become final and to the entry of a judgment in any jurisdiction upon
any award rendered or order issued in such proceeding that has become final. The
decision of the arbitrator shall be tendered within forth-five (45) days of the
final submission of the Parties in writing or in a hearing before the
arbitrator. Each such arbitration award that has become final shall be
conclusive and binding upon the Parties and shall not be appealable. Attorney's
fees, costs and other out-of-pocket expenses may be awarded by the arbitrator in
his discretion to the Party that prevails in any such arbitration, provided,
                                                                   --------
that if there is no prevailing Party, the arbitrator may award such fees, costs
and expenses in any manner the arbitrator sees fit. Each Party shall pay its own
expenses pending the awarding thereof to the Party that prevails in any such
arbitration.

         (h) Severability. In the event any provision, or portion thereof, of
this Agreement is held by a court having proper jurisdiction to be unenforceable
in any jurisdiction, then such portion or provision shall be deemed to be
severable as to such jurisdiction (but, to the extent permitted by law, not
elsewhere) and shall not affect the remainder of this Agreement, which shall
continue in full force and effect to the extent that the material purposes of
this Agreement can still be implemented. If any provision of this Agreement is
held to be so broad as to be unenforceable, such provision shall be interpreted
to be only so broad as is necessary for it to be enforceable.



                           [Signature Page to Follow]

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         IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed and delivered under seal as of the date first written above.







                                             /s/ Alexander P. Boxall
                                             ----------------------------------
                                             Alexander Boxall







                                   ADVANCED DEPOSITION TECHNOLOGIES, INC.

                                   By: /s/ Glenn J. Walters
                                       ----------------------------------------
                                       Glenn J. Walters, its Chief Executive 
                                       Officer, President and Treasurer



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