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                                                                     EXHIBIT 4.1


                                                                  Execution Copy




                              MOLL INDUSTRIES, INC.
                                     COMPANY


                                       AND



                       STATE STREET BANK AND TRUST COMPANY
                                     TRUSTEE

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                          FIRST SUPPLEMENTAL INDENTURE


                          DATED AS OF DECEMBER 28, 2001


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                                       TO


                     THE INDENTURE DATED AS OF JUNE 26, 1998
      BETWEEN MOLL INDUSTRIES, INC. (F/K/A ANCHOR ADVANCED PRODUCTS, INC.)
              AND STATE STREET BANK AND TRUST COMPANY, AS TRUSTEE,
               RELATING TO $130 MILLION AGGREGATE PRINCIPAL AMOUNT
             OF 10 1/2% SERIES B SENIOR SUBORDINATED NOTES DUE 2008



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                          FIRST SUPPLEMENTAL INDENTURE

         THIS FIRST SUPPLEMENTAL INDENTURE (the "Supplemental Indenture") is
made as of the 28th day of December, 2001, between Moll Industries, Inc. (f/k/a
Anchor Advanced Products, Inc.) (the "Company") and State Street Bank and Trust
Company, as trustee (the "Trustee").

         WHEREAS, the Company and the Trustee heretofore executed and delivered
an Indenture, dated as of June 26, 1998 (the "Indenture"); and

         WHEREAS, pursuant to the Indenture, the Company issued and the Trustee
authenticated and delivered $130 million aggregate principal amount of the
Company's 10 1/2% Senior Subordinated Notes due 2008 (the "Initial Notes"); and

         WHEREAS, pursuant to an exchange offer registered with the Securities
and Exchange Commission on a Registration Statement No. 333-60857 on Form S-4,
the Company offered to, and did, exchange $130 million in aggregate principal
amount of its 10 1/2% Series B Senior Subordinated Notes due 2008 (the "Exchange
Notes" and, together with the Initial Notes, the "Notes") for $130 million in
aggregate principal amount of the Initial Notes; and

         WHEREAS, Section 9.02 of the Indenture provides that the Company, when
authorized by resolutions of its Board of Directors, and the Trustee, with the
written consent of the Holders of not less than a majority in aggregate
principal amount of the Notes outstanding, may amend the Indenture, subject to
certain exceptions (none of which is applicable to the amendments (the
"Amendments") contained in Section 2.01 of this Supplemental Indenture)
specified in Section 9.02 of the Indenture; and

         WHEREAS, pursuant to its Offer to Purchase and Consent Solicitation,
dated September 19, 2001, as amended as of October 11, 2001 and as extended (the
"Consent Solicitation"), the Company solicited consents of the Holders to the
Amendments, which if adopted would (i) amend the Indenture by deleting therefrom
the provisions set forth below, and (ii) amend Section 1.01 of the Indenture by
amending the definition of the term "Subsidiary" therein; and

         WHEREAS, the Holders of not less than a majority in aggregate principal
amount of the outstanding Notes have duly consented to the Amendments set forth
in this Supplemental Indenture in accordance with Section 9.02 of the Indenture;
and

         WHEREAS, the Company has heretofore delivered or is delivering
contemporaneously herewith to the Trustee (i) a copy of resolutions of its Board
of Directors authorizing the execution, delivery and performance of this
Supplemental Indenture, (ii) evidence of the written consent of the Holders set
forth in the immediately preceding paragraph, (iii) an Officers' Certificate in
compliance with and to the effect set forth in Sections 1.01, 9.02 and 9.06 of
the Indenture and (iv) an Opinion of Counsel in compliance with and to the
effect set forth in Sections 1.01, 9.02 and 9.06 of the Indenture; and


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         WHEREAS, all conditions necessary to authorize the execution and
delivery of this Supplemental Indenture and to make this Supplemental Indenture
valid and binding have been complied with or have been done or performed;

         NOW, THEREFORE, in consideration of the foregoing and notwithstanding
any provision of the Indenture which, absent this Supplemental Indenture, might
operate to limit such action, the Company, Holdings and the Trustee agree as
follows for the equal and ratable benefit of the Holders of the Notes:

                                    ARTICLE I
                                   DEFINITIONS

         SECTION 1.01. GENERAL. For all purposes of the Indenture and this
Supplemental Indenture, except as otherwise expressly provided or unless the
context otherwise requires:

         (a) the words "herein", "hereof" and "hereunder" and other words of
similar import refer to the Indenture and this Supplemental Indenture as a whole
and not to any particular Article, Section or subdivision; and

         (b)      capitalized terms used but not defined herein shall have the
meanings assigned to them in the Indenture.

                                   ARTICLE II
                              AMENDMENTS AND WAIVER

         SECTION 2.01. AMENDMENTS. Subject to Section 3.01 hereof, the Indenture
is hereby amended in the following respects:

         (a)      Section 1.01 of the Indenture is hereby amended by amending
the definition of the term "Subsidiary" therein to read as follows:

                  "Subsidiary" means, with respect to any Person, (i) any
         corporation, association or other business entity of which more than
         50% of the total voting power of shares of Capital Stock entitled
         (without regard to the occurrence of any contingency) to vote in the
         election of directors, managers or trustees thereof is at the time
         owned or controlled, directly or indirectly, by such Person or one of
         more of the other Subsidiaries of that Person (or a combination
         thereof) and (ii) any partnership (a) the sole general partner or the
         managing general partner of which is such Person or a Subsidiary of
         such Person or (b) the only general partners of which are such Person
         or of one or more Subsidiaries of such Person (or any combination
         thereof). For purposes of this Indenture, any reference to a
         "Subsidiary" of the Company shall be deemed to exclude any entity
         organized or incorporated under the laws of any jurisdiction other than
         the United States of


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         America, its territories and possessions, any State of the United
         States, and the District of Columbia.

         (b)      The Indenture is hereby further amended by deleting Sections
4.02 to 4.13, inclusive, Sections 4.15 to 4.18, inclusive, Sections 5.01 and
5.02, Sections 6.01(c), (d), (e), (f) and (i), and Sections 11.03 and 11.04
thereof in their entirety.

         (c)      Section 12.02 of the Indenture is hereby amended by amending
and restating the first paragraph thereof to read as follows:

                  Any notice or communication by the Company, a Guarantor or the
         Trustee to the others is duly given if in writing and delivered in
         Person or mailed by first class mail (registered or certified, return
         receipt requested), telex, telecopier or overnight air courier
         guarantying next day delivery, to the others' address:

                           If to the Company and/or any Guarantor:

                           Moll Industries, Inc.
                           William W. Teeple
                           Vice President and
                           Chief Financial Officer
                           2100 S.W. 71st Terrace
                           Davie, FL  33317
                           Fax:  954-474-5992

                           With a copy to:

                           Nora J. Schneider, Esq.
                           Choate, Hall & Stewart
                           Exchange Place
                           53 State Street
                           Boston, MA  02109-2891
                           Telecopier No.:  (617) 248-4000

                           If to the Trustee:

                           State Street Bank and Trust Company
                           225 Asylum Street
                           Hartford, CT  06103
                           Attention:  Corporate Trust Department
                           Telecopier No.:   (860) 244-1889


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                           With a copy to:

                           Bruce M. Lutsk, Esq.
                           Reid & Riege, P.C.
                           One State Street
                           Hartford, CT  06103
                           Telecopier No.:  (860) 240-1002


                                   ARTICLE III
                                  MISCELLANEOUS

         SECTION 3.01. EFFECTIVENESS. This Supplemental Indenture shall become
effective upon its execution and delivery by the Company and the Trustee.
Notwithstanding the execution and delivery of the Supplemental Indenture by the
Company and the Trustee, the Amendments shall become effective only concurrently
with the payment of the Purchase Price (as defined in the Consent Solicitation)
and the making of the Consent Payment (as defined in the Consent Solicitation).
The Purchase Price and Consent Payment will be deemed to have been made when
paid by the deposit with the Depositary (as defined in the Consent
Solicitation), which will act as the agent for the tendering and consenting
Holders and transmit such payment to such Holders. The Indenture will remain in
effect without giving effect to the Amendments until the Purchase Price is paid
and the Consent Payment is made. Upon the execution and delivery of this
Supplemental Indenture by the Company and the Trustee, the Indenture shall be
supplemented in accordance herewith, and this Supplemental Indenture shall form
a part of the Indenture for all purposes, and every Holder of Notes heretofore
or hereafter authenticated and delivered under the Indenture shall be bound
thereby. Notwithstanding the foregoing provisions of this Section 3.01, if the
Purchase Price is not paid and the Consent Payment is not made on or prior to
December 31, 2001, the Amendments will not become effective and this
Supplemental Indenture will become null and void.

         SECTION 3.02. INDENTURE REMAINS IN FULL FORCE AND EFFECT. Except as
supplemented hereby, all provisions in the Indenture shall remain in full force
and effect.

         SECTION 3.03. INDENTURE AND SUPPLEMENTAL INDENTURE CONSTRUED TOGETHER.
This Supplemental Indenture is an indenture supplemental to and in
implementation of the Indenture, and the Indenture and this Supplemental
Indenture shall henceforth be read and construed together.

         SECTION 3.04. CONFIRMATION AND PRESERVATION OF INDENTURE. The Indenture
as supplemented by this Supplemental Indenture is in all respects confirmed and
preserved.

         SECTION 3.05. CONFLICT WITH TRUST INDENTURE ACT. If any provision of
this Supplemental Indenture limits, qualifies or conflicts with any provision of
the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act"), that is
required under the Trust Indenture Act to be part of and govern any provision of
this Supplemental Indenture, the provision of the


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Trust Indenture Act shall control. If any provision of this Supplemental
Indenture modifies or excludes any provision of the Trust Indenture Act that may
be so modified or excluded, the provision of the Trust Indenture Act shall be
deemed to apply to the Indenture as so modified or to be excluded by this
Supplemental Indenture, as the case may be.

         SECTION 3.06. SEVERABILITY. In case any provision in this Supplemental
Indenture shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.

         SECTION 3.07. HEADINGS. The Article and Section headings of this
Supplemental Indenture have been inserted for convenience of reference only, are
not to be considered a part of this Supplemental Indenture and shall in no way
modify or restrict any of the terms or provisions hereof.

         SECTION 3.08. BENEFITS OF SUPPLEMENTAL INDENTURE, ETC. Nothing in this
Supplemental Indenture or the Notes, express or implied, shall give to any
Person, other than the parties hereto and thereto and their successors hereunder
and thereunder and the Holders of the Notes, any benefit of any legal or
equitable right, remedy or claim under the Indenture, this Supplemental
Indenture or the Notes.

         SECTION 3.09. SUCCESSORS. All agreements of the Company and Holdings in
this Supplemental Indenture shall bind their respective successors. All
agreements of the Trustee in this Supplemental Indenture shall bind its
successors.

         SECTION 3.10. TRUSTEE NOT RESPONSIBLE FOR RECITALS. The recitals
contained herein shall be taken as the statements of the Company and Holdings,
and the Trustee assumes no responsibility for their correctness. The Trustee
shall not be liable or responsible for the validity or sufficiency of this
Supplemental Indenture.

         SECTION 3.11. CERTAIN DUTIES AND RESPONSIBILITIES OF THE TRUSTEE. In
entering into this Supplemental Indenture, the Trustee shall be entitled to the
benefit of every provision of the Indenture relating to the conduct or affecting
the liability or affording protection to the Trustee, whether or not elsewhere
herein so provided.

         SECTION 3.12. GOVERNING LAW. The internal law of the State of New York
shall govern and be used to construe this Supplemental Indenture.

         SECTION 3.13. COUNTERPART ORIGINALS. The parties may sign any number of
copies of this Supplemental Indenture. Each signed copy shall be original, but
all of them together represent the same agreement.


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         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date and year first
above written.

                                       MOLL INDUSTRIES, INC.



                                       By:  /s/ James T. Sprouse
                                          -------------------------------
                                       Name:   James T. Sprouse
                                       Title:  Corporate Controller

(SEAL)


Attest: /s/ George T. Votis
       ---------------------------
Name:  George T. Votis
Title: Chairman and Chief Executive Officer



                                       STATE STREET BANK AND TRUST
                                       COMPANY, as Trustee



                                       By: /s/ Michael M. Hopkins
                                          -------------------------------
                                       Name:  Michael M. Hopkins
                                              ---------------------------
                                       Title: Vice President