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                                  Exhibit 10-T

                           PATENT ASSIGNMENT AGREEMENT

         This Agreement is effective January 20, 2000 (the "Effective Date") by
and between Parlex Corporation, a Massachusetts corporation, having its
principal place of business at 145 Milk Street, Methuen, Massachusetts, 02855
(hereinafter referred to as "Parlex") and Polyclad Laminates, Inc., a
Massachusetts corporation having its principal place of business at 40
Industrial Park Drive, West Franklin, New Hampshire, 03235 (hereinafter referred
to as "Polyclad").

         WHEREAS Parlex is the owner of issued U.S. patents and corresponding
foreign patent applications, which are identified in Schedule A attached hereto,
hereinafter referred to as "Patents";

         WHEREAS Polyclad has certain License Rights under the Patents as set
forth in an Agreement between Parlex and Polyclad dated June 1, 1996;

         WHEREAS Polyclad is willing to acquire and Parlex is willing to convey
ownership in the Patents on the terms and conditions as set forth in this
Agreement.

         NOW THEREFORE in consideration of the premises and the mutual
obligations of the parties and other good and valuable consideration the receipt
and sufficiency of which are hereby acknowledged, the parties agree as follows:

         1.0      ASSIGNMENT

                  1.1 Parlex hereby sells and assigns to Polyclad all right,
                  title and interest in and to the Patents, including the right
                  to sue for past infringement, subject to certain pre-existing
                  licenses as set forth in Section 2.0 herein, and subject to
                  certain retained licensed rights of Parlex as set forth in
                  Section 3.0 herein.


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                  1.2 Parlex shall, upon execution of this Agreement, execute
                  confirmatory patent assignments recordable in the United
                  States Patent and Trademark Office, or appropriate foreign
                  patent offices in the form set forth in Exhibit 1 hereto.

         2.0      PRE-EXISTING LICENSES

                  2.1 Parlex has existing License Agreements with Allied Signal
                  Laminate Systems Inc., now Isola Laminate Systems Corp.,
                  Samsung Electro-Mechanics Co., Ltd., and Polyclad Laminates,
                  Inc. The Polyclad License Agreement is terminated as of the
                  effective date of this Agreement. The License Agreements with
                  Isola and with Samsung remain in effect.

                  2.2 Royalties paid to Parlex under the existing License
                  Agreement with Isola shall be paid by Parlex to Polyclad
                  within thirty (30) days of receipt by Parlex of each such
                  payment.

                  2.3 In the event that royalties under the existing License
                  Agreements are not paid or in the event of any other breach of
                  an existing License Agreement by a Licensee, Parlex shall so
                  inform Polyclad and shall take such action to recover royalty
                  payments or otherwise remedy the breach as is agreeable to
                  Polyclad and at the expense of Polyclad.

         3.0      LICENSE TO PARLEX

                  Parlex shall have and retain a non-cancelable royalty free
non-exclusive license under the Patents to make, have made, use, sell and
otherwise practice the inventions covered by any one or more claims of any and
all of the Patents throughout the world for Parlex's own use in the manufacture
and sale of circuit board products but not for the sale of foil having a cured
and semi-cured resin. Parlex shall have the right to sublicense or assign this
royalty free license to any Affiliate of Parlex and to any successor of the
business of Parlex to which this Agreement relates for use by such Affiliate or
successor in the manufacture and sale of circuit board products but not for the
sale of foil having a cured and semi-cured resin. Parlex shall have no other
right to sublicense any of its license rights granted under this Agreement.


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                  For purposes of this Agreement, "Affiliate" shall mean any
corporation, or other business entity, which Parlex either directly or
indirectly controls or which directly or indirectly controls Parlex or with
which Parlex is under common, direct or indirect control. As used herein, the
term "control" shall mean the holding of sufficient voting stock or other
indices of ownership: (1) to elect at least fifty percent (50%) of the directors
of such corporation, or (2) to cause the direction of the management and
policies of such other business entity.

         4.0      PAYMENTS

                  4.1 Polyclad shall pay to Parlex the amount of one million
                  three hundred thousand dollars ($1,300,000.00)payable in three
                  installments as follows:

                  (a) Five hundred thousand dollars ($500,000.00) on January 14,
                  2000;

                  (b) Five hundred thousand dollars ($500,000.00) within fifteen
                  (15) days following January 1, 2001; and

                  (c) Three hundred thousand dollars ($300,000.00) within
                  fifteen (15) days following January 1, 2002.

                  4.2 It is recognized that Polyclad has paid Parlex an amount
                  in excess of one million dollars ($1,000,000.00) since 1997
                  for license rights to the Patents under the license agreement
                  noted in Section 2.0 above.

                  4.3 Polyclad shall, upon execution of this Agreement, execute
                  a Security Assignment in the form attached hereto as Exhibit 2
                  and under which Parlex shall have a security interest in the
                  Patents until full payment of the one million three hundred
                  thousand dollars($1,300,000.00) called for under Section 4.1
                  hereof.

         5.0      PATENT MAINTENANCE AND PROSECUTION

                  Polyclad shall be responsible for payment of all patent
prosecution, maintenance and other expenses for the Patents which accrue after
the Effective Date of this Agreement, and shall be responsible for the diligent
prosecution of all pending foreign patent applications included in the Patents,
to the extent feasible or advisable in the reasonable view of Polyclad. Until
full payment of the one million three hundred thousand dollars ($1,300,000.00)
called for under


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<PAGE>

Section 4.1 hereof, Polyclad shall maintain all issued patents listed in
Schedule A and diligently prosecute all patent applications listed in Schedule
A. Promptly following execution of this Agreement, Parlex shall provide Polyclad
with the complete prosecution history of each patent and patent application
listed in Schedule A.

         6.0      REPRESENTATIONS

                  6.1 Parlex represents that:

                  (a) it owns all right, title and interest in the Patents
                  subject to the pre-existing licenses which have been granted
                  as noted in Section 2.0 above;

                  (b) applicable maintenance and/or annuity fees have been
                  timely paid for the Patents and are up to date in all
                  applicable jurisdictions;

                  (c) it has no knowledge of any infringement by others of the
                  Patents;

                  (d) it has no knowledge of any patents of others that would be
                  infringed by practice of the inventions covered by the
                  Patents; and

                  (e) it does not own any other patents or patent applications
                  that cover two pass coating of resin on copper foil to
                  different degrees of curing. Except for the foregoing and
                  except as set forth in Section 6.3 below, Parlex makes no
                  representation or warranty as to the validity of any of the
                  Patents or that the manufacture, use, sale or other
                  disposition of products covered by the Patents do not infringe
                  upon any domestic or foreign patent of any third party.

                  6.2 Each party represents that it has the right to enter into
                  this Agreement.

                  6.3 In the event that the patent coverage afforded by the
                  Patents is substantially diminished by final adverse decision
                  of a court or other tribunal of competent jurisdiction as to
                  patentability or validity based only on Fujitsu published
                  Japanese Application 61-204,242, issued as Japanese Patent No.
                  1,985,082 on October 25, 1995, Parlex shall pay to Polyclad an
                  amount equal to one million three hundred thousand dollars
                  ($1,300,000.00) less the total royalty payments received since
                  the Effective Date from Isola under the aforesaid pre-


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                  existing license agreement and less the amount of the
                  royalties that would have been received by Parlex from
                  Polyclad since the Effective Date had the pre-existing license
                  agreement with Polyclad remained in effect.

         7.0      PRODUCT LIABILITY

                  7.1 Each party shall be solely responsible for any and all
                  product liability with respect to its manufacture, use,
                  advertisement, sale, lease or other disposition of products
                  covered by the Patents

                  7.2 IN NO EVENT WILL EITHER PARTY BE LIABLE TO THE OTHER FOR
                  LOSS OF PROFITS OR ANY OTHER CONSEQUENTIAL, INCIDENTAL,
                  SPECIAL OR INDIRECT DAMAGES ARISING OUT OF THIS AGREEMENT.

         8.0      HEADINGS

                  Section headings are for convenience only and shall not be
construed to limit or extend the meaning of any portion of this Agreement.

         9.0      GOVERNING LAW

                  This Agreement shall be governed, construed and enforced in
accordance with the laws of the Commonwealth of Massachusetts and applicable
United States federal law.

         10.0     PUBLICITY

                  Neither party shall disclose the terms of this Agreement
without the prior written consent of the other party, provided however, that
either party may notify others of the fact that this Agreement is in effect and
may in the ordinary course of its business disclose some or all of the
provisions of this Agreement as may be required by governmental and corporate
financial reporting laws or regulations. In addition, neither party shall use
the name of the other party nor of any employee for advertising, promotional or
other purposes without the prior written consent of the other party.

         11.0     NO IMPLIED LICENSE

                  Nothing in this Agreement shall convey or imply any license or
right by Parlex or by Polyclad other than as expressly set forth in this
Agreement.


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         12.0     ADDITIONAL DOCUMENTS

                  Each party shall execute such other documents as the other
party reasonably determines is necessary or desirable to confirm or perfect the
rights granted under this Agreement.

         13.0     COUNTERPARTS

                  This Agreement is being executed simultaneously in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute the same instrument. Facsimile signatures shall be
considered original signatures.

         14.0     Assignment

         This Agreement may be assigned by Polyclad in its sole discretion, and
may be assigned by Parlex without the prior written permission of Polyclad in
conjunction with the sale of the business to which this Agreement relates, and
may otherwise be assigned by Parlex with the prior written permission of
Polyclad, which permission shall not unreasonably be withheld.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement to
be effective as of the day and year first written above.

POLYCLAD LAMINATES, INC.                    PARLEX CORPORATION

By _________________________                By _________________________________


Title ______________________                Title ______________________________


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<PAGE>

                                   SCHEDULE A

         To Patent Assignment Agreement between Parlex Corporation and Polyclad
Laminates, Inc. dated January 20, 2000

<TABLE>
<CAPTION>

                             PATENTS

Patent            Issue
No.               Date             Title                               Country
<S>               <C>              <C>                                 <C>
5,362,534         11/8/94          MULTIPLE LAYER PRINTED              U.S.A.
                                   CIRCUIT BOARDS AND METHOD
                                   OF MANUFACTURE

5,557,843         9/24/96          METHOD OF MAKING A CIRCUIT          U.S.A.
                                   BOARD OR LAYER THEREOF
                                   INCLUDING SEMI-CURING A
                                   SECOND ADHESIVE COATED ON
                                   A CURED FIRST ADHESIVE

195,528           2/12/99          MULTIPLE LAYER PRINTED              South
                                   CIRCUIT BOARDS AND                  Korea
                                   METHOD OF MANUFACTURE

ZL 94193145.5     8/21/99          MULTIPLE LAYER PRINTED              China
                                   CIRCUIT BOARDS AND METHOD
                                   OF MANUFACTURE

</TABLE>

<TABLE>
<CAPTION>

                             PATENT APPLICATIONS

Serial            Filing
No.               Date             Title                               Country
<S>               <C>              <C>                                 <C>
2,169,547         8/23/94          MULTIPLE LAYER PRINTED              Canada
                                   CIRCUIT BOARDS AND METHOD
                                   OF MANUFACTURE

94 925 993.1      8/23/94          MULTIPLE LAYER PRINTED              EPO
                                   CIRCUIT BOARDS AND METHOD
                                   OF MANUFACTURE

7-507722          8/23/94          MULTIPLE LAYER PRINTED              Japan
                                   CIRCUIT BOARDS AND METHOD
                                   OF MANUFACTURE

</TABLE>


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