<PAGE>
                                                                     EXHIBIT 1.3

                          "COMERICA -- 4TH AMENDMENT"
                                FOURTH AMENDMENT
                          TO RESTATED CREDIT AGREEMENT

    This Fourth Amendment to Restated Credit Agreement and Note dated as of
July 15, 1999 by and among IPG HOLDINGS LP, a Delaware limited partnership
("Borrower"), INTERTAPE POLYMER GROUP INC., a Canadian corporation ("Guarantor")
and COMERICA BANK, a Michigan banking corporation ("Bank").

    WHEREAS, Borrower, Guarantor and Bank entered into a Restated Revolving
Credit Agreement dated as of May 8, 1998 (the "Original Agreement" and as
amended by the First Amendment (defined below) the "Agreement"), pursuant to
which Borrower incurred certain indebtedness and obligations to Bank and issued
to Bank a certain Eurodollar Revolving Note in the face amount of Fifty Million
Dollars ($50,000,000) made by Borrower to Bank as of May 8, 1998 ("Note");

    WHEREAS, Borrower, Guarantor, and Bank entered into a First Amendment to
Credit Agreement dated as of September 1, 1998 (the "First Amendment"), pursuant
to which (i) a subfacility in favor of American Tape Co. ("ATC") was established
under the Agreement, and (ii) amounts available under the Revolving Facility
were limited, inter alia, by amounts outstanding under the ATC Note;

    WHEREAS, Borrower, Guarantor and Bank entered into a Second Amendment to
Credit Agreement dated as of January 22, 1999 (the "Second Amendment");

    WHEREAS, Borrower, Guarantor and Bank entered into a Third Amendment to
Restated Credit Agreement dated as of May 17, 1999 (the "Third Amendment");

    WHEREAS, Borrower, Guarantor and Bank desire to amend certain provisions of
the Agreement on the terms and conditions hereof;

    NOW, THEREFORE, it is agreed:

A.  DEFINITIONS

    1.  Capitalized terms used herein and not defined to the contrary have the
       meanings given them in the Agreement.

B.  AMENDMENT TO AGREEMENT

    1.  All references to the Note in the Agreement, including, but not limited
       to the reference in Section 1.3 of the Agreement, shall mean that certain
       Eurodollar Revolving Note in the principal amount of $60,000,000 executed
       and delivered by Borrower to Bank of even date herewith as a replacement
       to that certain Note executed and delivered in connection with the
       Agreement (the "Replacement Note"). Advance under the Replacement Note
       are limited by amounts outstanding under the ATC Note (as defined in the
       Second Amendment, as amended).

    2.  The definition of "COMMITMENT AMOUNT" set forth in Section 7.1 of the
       Agreement shall be amended to read as follows: "COMMITMENT AMOUNT" means
       Sixty Million Dollars ($60,000,000)."

C.  REPRESENTATIONS

    Borrower hereby represents and warrants that:

    1.  Execution, delivery and performance of this Amendment and any other
       documents and instruments required under this Amendment or the Agreement
       are within Borrower's and Company's powers, have been duly authorized,
       are not in contravention of law or the terms of their respective
       governing instruments, and do not require the consent or approval of any
       governmental body, agency, or authority.

                                       5
<PAGE>
    2.  This Amendment, and the Agreement as amended by this Amendment, and any
       other documents and instruments required under this Amendment or the
       Agreement, when issued and delivered under this Amendment or the
       Agreement, will be valid and binding in accordance with their terms.

    3.  The covenants of Borrower and Company set forth in Article V of the
       Agreement are true and correct as of the date hereof.

    4.  No Event of Default, 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.

D.  MISCELLANEOUS

    1.  This Amendment may be executed in counterparts and shall be deemed to
       become effective upon such execution and delivery hereof and upon
       delivery to Bank of each of the other documents listed on the checklist
       attached hereto as Exhibit "A", all in form and content satisfactory to
       Bank.

    2.  Borrower and Company acknowledge and agree that, except as specifically
       amended hereby or in connection herewith, all of the terms and conditions
       of the Agreement and the other loan documents, remain in full force and
       effect in accordance with their original terms.

    3.  Except as specifically set forth herein, nothing set forth in this
       Amendment shall constitute, or be interpreted or construed to constitute,
       a waiver of any right or remedy of Bank, or of any default or event of
       default whether now existing or hereafter arising.

    4.  This Amendment, and the Agreement as amended hereby, shall be
       interpreted, construed and governed by the laws of the State of Michigan.

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

<TABLE>
<S>                                              <C>
COMERICA BANK                                    IPG HOLDINGS LP
                                                 By: Intertape Polymer Inc.
                                                 Its: General Partner

By: /s/Darlene Persons                           By: /s/Andrew M. Archibald

Its: Vice President                              Its: CFO & Secretary

INTERTAPE POLYMER GROUP INC.

By: /s/Andrew M. Archibald

Its: CFO, Secretary-Treasurer & VP
Administration
</TABLE>

                                       6