<PAGE>   1
                                                                   Exhibit 10.19


                      EIGHTH AMENDMENT TO CREDIT AGREEMENT

                  THIS EIGHTH AMENDMENT (this "Amendment") to CREDIT AGREEMENT
among SPINNAKER COATING, INC., a Delaware corporation, formerly known as
Brown-Bridge Industries, Inc. ("Coating"), ENTOLETER, INC., a Delaware
corporation ("Entoleter"), SPINNAKER COATING-MAINE, INC., a Delaware corporation
("SCM" and, together with Coating and Entoleter, the "Borrowers"), SPINNAKER
INDUSTRIES, INC., a Delaware corporation (the "Guarantor" and, together with the
Borrowers, the "Credit Parties"), the financial institutions from time to time
party thereto as lenders (the "Lenders"), and TRANSAMERICA BUSINESS CAPITAL
CORPORATION (as successor of Transamerica Business Credit Corporation), as agent
(in such capacity the "Agent") for the Lenders, is made as of August 14, 2001
among the Credit Parties and the undersigned Lenders.

                              W I T N E S S E T H :

                  WHEREAS, the Credit Parties, the Lenders and the Agent are
parties to the Credit Agreement, dated as of August 9, 1999 (as amended,
restated or otherwise modified from time to time prior to the date of
effectiveness of this Amendment, the "Credit Agreement"; capitalized terms used
herein shall have the meanings assigned to such terms in the Credit Agreement
unless otherwise defined herein);

                  WHEREAS, the Credit Parties have requested that the Lenders
make the amendments set forth herein to the Credit Agreement; and

                  WHEREAS, the Lenders are agreeable to such request, but only
on the terms and subject to the conditions set forth herein.

                  NOW, THEREFORE, in consideration of the foregoing and for
other good and valuable consideration, the parties hereto hereby agree as
follows:

         1.       AMENDMENTS TO CREDIT AGREEMENT. Subject to the satisfaction of
the conditions to effectiveness set forth in Section 2 hereof, the Credit
Parties and the Lenders agree to amend the Credit Agreement as follows:

                  (a) Section 1.1 of the Credit Agreement is hereby amended to
add the following new defined terms in alphabetical order:

                            "Accommodation Period" means the period commencing
                  on the Amendment No. 8 Effective Date and ending on the
                  Accommodation Period Termination Date.

                            "Accommodation Period Termination Date" means the
                  earlier of (i) the 90th day following the Amendment No. 8
                  Effective Date or (ii) the date on which an Event of Default
                  shall have occurred following the Amendment No. 8 Effective
                  Date.


<PAGE>   2

                            "Amendment No. 8" means that certain Eighth
                  Amendment to Credit Agreement dated as of August 14, 2001 by
                  and among the Credit Parties, the Lenders and the Agent.

                            "Amendment No. 8 Effective Date" means the date on
                  which all of the conditions precedent to the effectiveness of
                  the Amendment No. 8 have been satisfied.

                            "Overadvance" shall mean, with respect to any
                  Borrower, the amount, if any, by which the aggregate amount of
                  Revolving Loans and Letter of Credit Obligations owing by such
                  Borrower exceeds the lesser of (i) the Borrowing Base of such
                  Borrower minus any reserves applicable to such Borrower or
                  (ii) the amount of Loans and Letter of Credit Obligations
                  permitted to be incurred by such Borrower under the applicable
                  Accounts Coverage Requirement set forth in Section 2.1(a)
                  hereof minus any reserves applicable to such Borrower.

                            "Supporting Letter of Credit" means the letter of
                  credit issued by a bank or financial institution and on terms
                  acceptable to Agent in the amount of Two Million Dollars
                  ($2,000,000) in favor of Agent, in form and substance
                  substantially similar to the form attached to Amendment No. 8
                  as Schedule I.

                            "Supporting Letter of Credit Drawing Event" means
                  any of the following events: (i) Borrowers fail to have Unused
                  Availability of not less than $1,500,000 for at least 15
                  consecutive days immediately after the Accommodation Period
                  Termination Date ("Unused Availability Drawing Event"), (ii)
                  after the Accommodation Period Termination Date, any Borrower
                  fails to comply with the (x) the forty-five percent (45%)
                  Accounts Coverage Requirement in the case of Entoleter and (y)
                  the fifty percent (50%) Accounts Coverage Requirement in the
                  case of Coating and SCM as set forth under Section 2.1(a) of
                  the Credit Agreement, in either case, for at least 15
                  consecutive days immediately after the Accommodation Period
                  Termination Date ("Accounts Coverage Drawing Event"); (iii) at
                  any time during the Accommodation Period an Overadvance shall
                  exist ("Overadvance Drawing Event") or (iv) Borrowers shall
                  fail to timely provide the officer's certificate described in
                  Section 7.1(y) hereof following the Accommodation Period
                  Termination Date (a "Certificate Drawing Event").

                  (b) The definition of "Applicable Margin" in Section 1.1 of
the Credit Agreement is hereby amended by adding the following at the end
thereof:

                            "; provided, further, that after the Amendment No. 8
                  Effective Date the Applicable Margin shall be the applicable
                  percentage per annum determined by reference to the Debt to
                  EBITDA Ratio as set forth above for Prime Rate Loans,
                  Eurodollar Rate Loans and Letters of Credit plus an additional
                  0.25%."

                  (c) Section 2.1(a) of the Credit Agreement is hereby amended
and restated in its entirety to read as follows:

                            "(i) to Coating: an aggregate amount equal to the
                  lesser of (x) the Coating Line of Credit and (y) the Coating
                  Borrowing Base, minus in each case, the then outstanding
                  Coating Letter of Credit Obligations and the pending
                  Borrowings of Coating; provided that if the sum of the
                  outstanding Revolving Loans extended by the Lenders to Coating
                  and Coating Letter of Credit


<PAGE>   3


                  Obligations exceed $3,000,000, then no additional Revolving
                  Loan or Letter of Credit may be incurred by Coating if after
                  giving effect thereto an amount equal to fifty percent (50%)
                  of the sum of such Revolving Loans and Coating Letter of
                  Credit Obligations in excess of $3,000,000 exceeds the Coating
                  Accounts Borrowing Base (such 50% requirement, the "Coating
                  Accounts Coverage Requirement");

                           (ii) to Entoleter: an aggregate amount equal to the
                  lesser of (x) the Entoleter Line of Credit and (y) the
                  Entoleter Borrowing Base, minus, in each case, the then
                  outstanding Entoleter Letter of Credit Obligations and the
                  Pending Borrowings of Entoleter; provided that no Revolving
                  Loan or Letter of Credit may be incurred if after giving
                  effect thereto an amount equal to forty-five percent (45%) of
                  the sum of the Revolving Loans extended by the Lenders to
                  Entoleter and Entoleter Letter of Credit Obligations exceeds
                  the Entoleter Accounts Borrowing Base (such 45% requirement,
                  the "Entoleter Accounts Coverage Requirement"); and

                           (iii) to SCM: an aggregate amount equal to the lesser
                  of (x) the SCM Line of Credit and (y) the SCM Borrowing Base,
                  minus, in each case, the then outstanding SCM Letter of Credit
                  Obligations and the Pending Borrowings of SCM; provided that
                  no Revolving Loan or Letter of Credit may be incurred if after
                  giving effect thereto an amount equal to fifty percent (50%)
                  of the sum of the Revolving Loans extended by the Lenders to
                  SCM and SCM Letter of Credit Obligations exceeds the SCM
                  Accounts Borrowing Base. (such 50% requirement, the "SCM
                  Accounts Coverage Requirement" and together with the Coating
                  Accounts Coverage Requirement and the Entoleter Accounts
                  Coverage Requirement, individually an "Accounts Coverage
                  Requirement" and collectively, the "Accounts Coverage
                  Requirements").

Notwithstanding the foregoing, during the Accommodation Period, the applicable
Accounts Coverage Requirements set forth in clauses (i), (ii) and (iii) above
shall be reduced to forty percent (40%) in the case of each Borrower, except in
the case of funding any interest or principal payment in respect of the Senior
Notes (in which case Borrowers must comply with the original (x) forty-five
percent (45%) Accounts Coverage Requirement in the case of Entoleter and (y)
fifty percent (50%) Accounts Coverage Requirement in the case of Coating and SCM
as set forth in clauses (i), (ii) and (iii) above prior and after giving effect
to any such payment); provided, that (a) after the Accommodation Period
Termination Date such forty percent (40%) Accounts Coverage Requirement shall
immediately revert to the original (x) forty-five percent (45%) Accounts
Coverage Requirement in the case of Entoleter and (y) fifty percent (50%)
Accounts Coverage Requirement in the case of Coating and SCM as set forth in
clauses (i), (ii) and (iii) above."

                  (d) Section 7.1(v) is hereby amended by adding the following
at the end thereof:

                           "; provided, that solely during the Accommodation
                  Period, Borrowers shall not be required to meet this minimum
                  Unused Availability requirement except in the case of funding
                  any interest or principal payment in respect of the Senior
                  Notes (in which case Borrowers must have Unused Availability
                  of not less than $1,500,000 prior and after giving effect to
                  any such payment); provided, however, that after the
                  Accommodation Period Termination Date, Borrowers shall be
                  required to maintain at all times Unused Availability of not
                  less than $1,500,000."


<PAGE>   4

                  (e) Section 7.1 of the Credit Agreement is hereby amended by
adding the following new subsections (x), (y) and (z) at the end thereof:

                           "(x) Supporting Letter of Credit. The Credit Parties
                  shall deliver the Supporting Letter of Credit to Agent on or
                  prior to the Amendment No. 8 Effective Date. Agent shall be
                  eligible to draw under the Supporting Letter of Credit by
                  submitting a letter of credit drawing certificate in form set
                  forth on Exhibit A to the Supporting Letter of Credit attached
                  to Amendment No. 8. as Schedule I upon the occurrence of a
                  Supporting Letter of Credit Drawing Event for the following
                  amounts (i) in the case of an Unused Availability Drawing
                  Event for the applicable shortfall amount as determined by
                  Agent in good faith; (ii) in the case of an Accounts Coverage
                  Drawing Event for the applicable shortfall amount as
                  determined by Agent in good faith; (iii) in the case of an
                  Overadvance Drawing Event for the amount of such Overadvance
                  as determined by Agent in good faith; and (iv) in the case of
                  a Certificate Drawing Event for the amount of any shortfall or
                  Overadvance in respect of any suspected Supporting Letter of
                  Credit Drawing Event which the Agent, in good faith, shall
                  determine at such time.

                           (y) Officer's Certificate. Borrowers shall deliver to
                  Agent a Borrowing Base Certificate certified by the chief
                  financial officer of each Borrower not later than 10 days
                  following the Accommodation Period Termination Date which
                  certifies and demonstrates (with appropriate calculations and
                  supporting documentation) that no supporting Letter of Credit
                  Drawing Event has occurred or is continuing.

                           (z) Supporting Letter of Credit. Not later than seven
                  (7) Business Days following the Amendment No. 8 Effective
                  Date, Borrower shall cause to be issued and delivered to Agent
                  the Supporting Letter of Credit."

                  (f) Section 7.2(z) of the Credit Agreement is hereby amended
and restated to read in its entirety as follows:

                           "(z) Permitted Restructuring Charges During the
                  period from October 1, 2000 through June 30, 2002 the
                  Borrowers shall not incur aggregate cash Restructuring Charges
                  in excess of $6,800,000 nor incur aggregate cash and non-cash
                  Restructuring Charges in excess of $7,900,000 (collectively,
                  the "Permitted Restructuring Charges"), provided, further,
                  that without limiting the foregoing, in no event shall the
                  amount of such Permitted Restructuring Charges (whether cash
                  or non-cash) incurred during the period from January 1, 2001
                  through June 30, 2002 exceed $5,500,000."

         2.       CONDITIONS TO EFFECTIVENESS. This Amendment shall become
effective upon satisfaction of the following conditions:

                  (a) the Agent shall have received this Amendment, duly
executed by each of the Credit Parties and the Required Lenders;

                  (b) the Agent shall have received a secretary's or assistant
secretary's certificate of each Credit Party regarding the incumbency of each of
the officers authorized to sign this Amendment and certifying and attaching the
board resolutions authorizing the execution, delivery and performance of this
Amendment;


<PAGE>   5

                  (c) each of the representations and warranties set forth in
Section 3 hereof shall be true and correct in all respects; and

                  (d) the Agent shall have received for the ratable benefit of
the Lenders an amendment fee of $25,000 from Borrowers in respect of this
Amendment.

         3.       REPRESENTATIONS, WARRANTIES AND COVENANTS OF CREDIT PARTIES.

                  (I) Each Credit Party represents and warrants that:

                  (a) the execution, delivery and performance by such Credit
Party of this Amendment have been duly authorized by all necessary corporate
action and this Amendment is a legal, valid and binding obligation of such
Credit Party enforceable against such Credit Party in accordance with its terms,
except as the enforcement thereof may be subject to (i) the effect of any
applicable bankruptcy, insolvency, reorganization, moratorium or similar law
affecting creditors' rights generally and (ii) general principles of equity
(regardless of whether such enforcement is sought in a proceeding in equity or
at law);

                  (b) each of the representations and warranties contained in
the Credit Agreement is true and correct in all material respects on and as of
the date hereof as if made on the date hereof, except to the extent that such
representations and warranties expressly relate to an earlier date; and

                  (c) no Change of Control or other Event of Default has
occurred or remains outstanding as of the date hereof.

                  (II) Each Borrower hereby covenants and agrees that prior to
causing the Supporting Letter of Credit to be issued to and delivered to Agent,
no Borrower shall be entitled to request or receive any Revolving Loans or
create any additional Letter of Credit Obligations which, in either case, would
cause the aggregate amount of Unused Availability to be less than $2,000,000.

         4.       FEES AND EXPENSES. The Credit Parties shall pay for all of the
reasonable costs and expenses incurred by the Agent in connection with the
transactions contemplated by this Amendment, including, without limitation, the
reasonable fees and expenses of counsel to the Agent. The Credit Parties
acknowledge and agree that the Agent may charge any fees and all such costs and
expenses which may be owing to the Agent under this Amendment and/or any other
Credit Document to such of the Borrowers' Loan Accounts as Agent may elect in
its discretion.

         5.       MISCELLANEOUS.

                  (a) Except as expressly amended herein, all of the terms and
provisions of the Credit Agreement and the other Credit Documents are ratified
and confirmed in all respects and shall remain in full force and effect. Each
Credit Party hereby acknowledges and agrees that there is no defense, setoff or
counterclaim of any kind, nature or description to the Obligations or the
payment thereof when due.

                  (b) Upon the effectiveness of this Amendment, all references
in the Credit Documents to the Credit Agreement shall mean the Credit Agreement
as amended by this Amendment and all references in the Credit Agreement to "this
Agreement," "hereof," "herein," or similar terms, shall mean and refer to the
Credit Agreement as amended by this Amendment.


<PAGE>   6

                  (c) The execution, delivery and effectiveness of this
Amendment shall not, except as expressly provided herein, operate as an
amendment to or waiver of any right, power or remedy of the Agent or any Lender
under any of the Credit Documents, or constitute an amendment or waiver of any
provision of any of the Credit Documents.

                  (d) This Amendment may be executed by the parties hereto
individually or in combination, in one or more counterparts, each of which shall
be an original and all of which shall constitute one and the same agreement.
This Amendment may be executed and delivered by telecopier with the same force
and effect as if the same were a fully executed and delivered original manual
counterpart.

                  (e) This Amendment shall constitute a Credit Document.


         6.       GOVERNING LAW. THE VALIDITY, INTERPRETATION AND ENFORCEMENT OF
THIS AMENDMENT SHALL BE GOVERNED BY THE LAWS OF THE STATE OF NEW YORK WITHOUT
GIVING EFFECT TO THE CONFLICTS OF LAW PRINCIPLES THEREOF (OTHER THAN SECTION
5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW).