Document:

Exhibit 10.3

                                                     April 15, 2004

To the Lenders party to the Credit
   Agreement referred to below, c/o the
   Administrative Agent thereunder

     Re: $475,000,000 Amended and Restated Credit Agreement dated as of
         April 2, 2004

Ladies and Gentlemen:

                  Reference is made to the $475,000,000 Amended and Restated
Credit Agreement dated as of April 2, 2004 (the "Credit Agreement") among ISP
Chemco Inc., ISP Chemicals Inc., ISP Technologies Inc. and ISP Minerals Inc., as
borrowers (collectively, the "Borrowers"), the Subsidiary Guarantors party
thereto, the Lenders party thereto and JPMorgan Chase Bank, as administrative
agent for such Lenders (the "Administrative Agent"). Terms used but not defined
herein are used as defined in the Credit Agreement.

                  The Lead Borrower hereby notifies the Administrative Agent
pursuant to Section 2.08(b) of the Credit Agreement and subject to the terms and
conditions thereof (i) of its election to reduce the aggregate amount of the
Revolving Credit Commitments such that after giving effect to such reduction,
the aggregate amount of Revolving Credit Commitments shall be equal to
$200,000,000 (the "Revolving Credit Commitment Reduction"), to be allocated
among the Lenders or the financial institutions that will become Lenders on the
Extension Effective Date (as defined below), as the case may be, in accordance
with Schedule I to this Letter Agreement (which shall be deemed to replace the
relevant section of Schedule I to the Credit Agreement from and after the
Extension Effective Date) and (ii) that the effective date of such reduction
shall be the Extension Effective Date (as defined below).

                  The Borrowers hereby request that, subject to the following
sentence:

                  (i) pursuant to Section 2.08(g) of the Credit Agreement and
         subject to the terms and conditions thereof, the Revolving Credit
         Commitment Termination Date be extended by five years from the date of
         this Letter Agreement (the "Revolving Credit Commitment Extension");

                  (ii) in connection with the Revolving Credit Commitment
         Reduction, the Lenders waive the requirement contained in Section
         2.08(c) of the Credit Agreement that notice by the Lead Borrower of any
         election to reduce the Revolving Credit Commitments be given at least
         three Business Days prior to the effective date of such reduction (the
         "Notice Period Waiver");

<PAGE>
                                      -2-

                  (iii) (a) the definition of "Applicable Level" contained in
         Section 1.01 of the Credit Agreement be amended by (1) replacing the
         table contained therein with the table attached hereto as Annex 1 and
         (2) replacing the words "Level V" appearing at the end thereof with the
         words "Level IV" and (b) the definition of "Applicable Margin"
         contained in Section 1.01 of the Credit Agreement be amended by
         replacing the table contained therein with the table attached hereto as
         Annex 2; and

                  (iv) each of BNP Paribas and Deutsche Bank Trust Company
         Americas be given the title of Co-Documentation Agent, and each of Bear
         Stearns Corporate Lending Inc. and UBS AG, Stamford Branch be given the
         title of Co-Syndication Agent, provided that, anything herein or in the
         Credit Agreement to the contrary notwithstanding, the Co-Documentation
         Agents and Co-Syndication Agents named above shall have no duties or
         responsibilities hereunder or under the Credit Agreement except in
         their respective capacities as a Lender.

                  The foregoing requests of the Borrowers (the "Requests") shall
be approved and effective for all purposes of the Credit Agreement on the date
(the "Extension Effective Date") upon which the Administrative Agent shall
notify the Borrowers and the Lenders that the Administrative Agent has received:

                  (i) a copy, certified by the Secretary of each Borrower, of
         resolutions duly adopted by the Board of Directors of each Borrower
         approving the Requests;

                  (ii) a favorable written opinion (addressed to the
         Administrative Agent, the LC Bank and the Lenders and dated the
         Extension Effective Date) of Peter Ganz, General Counsel to the
         Obligors, in form and substance satisfactory to the Administrative
         Agent;

                  (iii) evidence satisfactory to the Administrative Agent of
         payment (or irrevocable instructions for payment) by the Lead Borrower
         in full of the principal of and interest on the Loans of the Revolving
         Credit Lenders, and all fees and other amounts (including, without
         limitation, any amounts payable under Section 2.15 of the Credit
         Agreement) owing to such Revolving Credit Lenders, under the Credit
         Agreement;

                  (iv) evidence satisfactory to the Administrative Agent of
         payment (or irrevocable instructions for payment) by the Borrowers in
         full of all fees required to be paid on or before the Extension
         Effective Date to the Administrative Agent (for its own account) or any
         Lender in connection with this Letter Agreement;

                  (v) evidence satisfactory to the Administrative Agent of the
         consent to the Requests by the Required Lenders and all of the
         Revolving Credit Lenders (other than any Declining Revolving Credit
         Lenders), including, for purposes of this Letter Agreement, those
         financial institutions listed on Schedule I hereto that will become
         Revolving Credit Lenders on the Extension Effective Date (the
         "Continuing Revolving Credit Lenders"); and

                  (vi) from each Revolving Credit Lender whose name does not
         appear on Schedule I hereto, a written acknowledgment satisfactory to
         the Administrative Agent

<PAGE>
                                      -3-

         that such Revolving Credit Lender is a Declining Revolving Credit
         Lender for all purposes of Section 2.08(g) of the Credit Agreement.

                  Upon the occurrence of the Extension Effective Date,
automatically and without further action on the part of the LC Bank or the
Lenders, the participations of the Revolving Credit Lenders in outstanding
Letters of Credit shall be reallocated among the Continuing Revolving Credit
Lenders such that, after giving effect thereto, the Continuing Revolving Credit
Lenders hold participations in outstanding Letters of Credit pro rata in
accordance with their respective Revolving Credit Commitments.

                  Each Borrower on behalf of itself, and the Lead Borrower on
behalf of each other Obligor, hereby confirms and represents and warrants to the
Administrative Agent and the Lenders that (i) the representations and warranties
of such Borrower and each other Obligor, as the case may be, set forth in the
Credit Agreement (including Sections 4.02 and 4.03 thereof), and of each Obligor
in each of the other Credit Documents to which it is a party, are true and
correct on and as of the date of this Letter Agreement as if made on and as of
such date, and as if each reference therein to the Credit Agreement included
reference to this Letter Agreement and (ii) as of the date of this Letter
Agreement no Default has occurred and is continuing.

                  Please execute and return to the Lead Borrower a counterpart
of this Letter Agreement confirming your consent and agreement to the Requests.
This Letter Agreement shall constitute a Credit Document for all purposes of the
Credit Agreement.

                  Except as herein provided, the Credit Agreement shall remain
unchanged and in full force and effect. This Letter Agreement may not be amended
or waived except by an instrument in writing signed by the Borrowers and the
Required Revolving Credit Lenders. This Letter Agreement shall be construed in
accordance with and governed by the law of the State of New York. This Letter
Agreement may be executed in counterparts (and by different parties hereto on
different counterparts), each of which shall constitute an original, but all of
which when taken together shall constitute a single contract. Delivery of an
executed counterpart of this Letter Agreement by telecopy shall be effective as
delivery of a manually executed counterpart hereof.

                                Very truly yours,

                                ISP CHEMCO INC.,
                                  individually as Borrower and as Lead Borrower

                                By  /s/ Neal E. Murphy
                                  -------------------------------
                                  Name:   Neal Murphy
                                  Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>
                                      -4-

                                ISP CHEMICALS INC.
                                ISP TECHNOLOGIES INC.
                                ISP MINERALS INC.

                                By  /s/ Neal E. Murphy
                                  -------------------------------
                                  Name:   Neal Murphy
                                  Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>
                                      -5-

                                    LENDERS
                                    -------

                                JPMORGAN CHASE BANK,
                                as Administrative Agent, Lender, LC Bank and
                                   Swingline Lender

                                By  /s/ Peter A. Dedousis
                                  ------------------------------
                                  Name:   Peter A. Dedousis
                                  Title:  Managing Director

                                BNP PARIBAS

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                BEAR STEARNS CORPORATE LENDING INC.

                                By
                                  -------------------------------
                                  Name:
                                  Title:

                                UBS AG, STAMFORD BRANCH

                                By
                                  ------------------------------
                                  Name:
                                  Title:

<PAGE>
                                      -6-

                                DEUTSCHE BANK TRUST COMPANY
                                  AMERICAS

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                VAN KAMPEN SENIOR INCOME TRUST

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                VAN KAMPEN SENIOR LOAN FUND

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                KZH CRESCENT 2 LLC

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                KZH CRESCENT 3 LLC

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                      -7-

                                PRINCIPAL LIFE INSURANCE COMPANY

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                MORGAN STANLEY PRIME INCOME TRUST

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                C-SQUARED CDO LTD.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                CELERITY CLO LTD

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                TCW SELECT LOAN FUND, LIMITED

                                By
                                  ---------------------------
                                  Name:
                                  Title:

<PAGE>
                                      -8-

                                LOAN FUNDING I LLC

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                ING-ORYX CLO, LTD.

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                ARCHIMEDES FUNDING IV, LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                SEQUILS ING I (HBDGM), LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                NEMEAN CLO, LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

<PAGE>
                                      -9-

                                ARCHIMEDES FUNDING III, LTD.

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                ENDURANCE CLO I LTD.

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                PROMETHEUS INVESTMENT FUNDING NO. 2

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                FLAGSHIP CLO 2001-1

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                FLAGSHIP CLO II

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -10-

                                GRAYSON AND CO.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                EATON VANCE INSTITUTIONAL SENIOR
                                  LOAN FUND

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                EATON VANCE CDO III, LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                COSTANTINUS EATON VANCE CDO V, LTD

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                EATON VANCE CDO VI, LIMITED

                                By
                                  --------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -11-

                                EATON VANCE LIMITED DURATION
                                  INCOME FUND

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                EATON VANCE SENIOR INCOME TRUST

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                SENIOR DEBT PORTFOLIO

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                OXFORD STRATEGIC INCOME FUND

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                TOLLI & CO.

                                By
                                  --------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -12-

                                EATON VANCE SENIOR FLOATING RATE
                                  TRUST

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                SRF 2000, INC.

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                SRF TRADING, INC.

                                By
                                  -------------------------
                                  Name:
                                  Title:

                                TRUMBULL THC, LTD.

                                By
                                  ------------------------
                                  Name:
                                  Title:

                                STANWICH LOAN FUNDING LLC

                                By
                                  -------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -13-

                                SIERRA CLO I LTD.

                                By
                                  --------------------------
                                  Name:
                                  Title:

                                OLYMPIC CLO I, LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                GRAYSTON CLO 2001-01 LTD.

                                By
                                  ---------------------------
                                  Name:
                                  Title:

                                GALLATIN FUNDING I LTD.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                BEAR STEARNS LOAN TRUST

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -14-

                                BRAYMOOR & CO.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                GRAYSTON CLO II 2004-1 LTD.

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                BILL AND MELINDA GATES FOUNDATION

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                MAPLEWOOD (CAYMAN) LIMITED

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                ELC (CAYMAN) LTD. 2000-1

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -15-

                                MASSACHUSETTS MUTUAL LIFE
                                  INSURANCE COMPANY

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                SUFFIELD CLO, LIMITED

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                TRYON CLO LTD. 2000-1

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                APEX (IDM) CDO I, LTD.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                ELC (CAYMAN) LTD. 1999-II

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -16-

                                ELC (CAYMAN) LTD. 1999-III

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                C.M. LIFE INSURANCE CO.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                BABSON CLO LTD. 2003-I

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                SIMSBURY CLO, LIMITED

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                SEABOARD CLO 2000 LTD.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -17-

                                BABSON CLO LTD. 2004-I

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                WINGED FOOT FUNDING TRUST

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                JUPITER LOAN FUNDING LLC

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                TORONTO DOMINION (NEW YORK) INC.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                HARCH CLO I LIMITED

                                By
                                  -----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -18-

                                METROPOLITAN LIFE INSURANCE CO.

                                By
                                  ----------------------------
                                  Name:
                                  Title:

                                METLIFE BANK, NATIONAL ASSOCIATION

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                JISSEKIKUN FUNDING, LTD.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                SEQUILS-MAGNUM, LTD.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                WAVELAND-INGOTS, LTD.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -19-

                                WRIGLEY CDO, LTD.

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                CATALINA CDO LTD.

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                LOAN FUNDING III LLC

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                PIMCO HIGH YIELD FUND

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                PETRUSSE EUROPEAN CLO SA

                                By
                                  -----------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -20-

                                CHARTER VIEW PORTFOLIO

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                DIVERSIFIED CREDIT PORTFOLIO LTD.

                                By
                                  -----------------------------
                                  Name:
                                  Title:

                                INVESCO EUROPEAN CDO I S.A.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                CHAMPLAIN CLO, LTD.

                                By
                                  ------------------------------
                                  Name:
                                  Title:

                                SPS HIGH YIELD LOAN TRADING

                                By
                                  ------------------------------
                                  Name:
                                  Title:

<PAGE>
                                     -21-

                                                              SCHEDULE I

                                  Commitments
                                  -----------
               (in each case as of the Extension Effective Date)

       [See definitions of "Lenders", "Revolving Credit Commitment" and
        "Term Loan Commitment" in Section 1.01 of the Credit Agreement]

                         Revolving Credit Commitments
                         ----------------------------

Revolving Credit Lender                                 Commitment Amount
-----------------------                                 -----------------

JPMORGAN CHASE BANK                                     $  45,000,000.00

BNP PARIBAS                                             $  43,000,000.00

BEAR STEARNS CORPORATE LENDING INC.                     $  40,000,000.00

UBS AG, STAMFORD BRANCH                                 $  36,000,000.00

DEUTSCHE BANK TRUST COMPANY AMERICAS                    $  36,000,000.00
                                                        ----------------

TOTAL REVOLVING CREDIT LENDERS                          $ 200,000,000.00
                                                        ================

<PAGE>
                                     -22-

                                                                   ANNEX 1

-------------------------------------------------------------

                      Applicable Level
-------------------------------------------------------------

      Level                   Total Debt Leverage
      -----                    Maintenance Ratio
                               -----------------
------------------ ------------------------------------------

        I                     Less than 2.0 to 1
------------------ ------------------------------------------

       II              Equal to or greater than 2.0 to 1
                            and less than 3.0 to 1
------------------ ------------------------------------------

       III             Equal to or greater than 3.0 to 1
                            and less than 4.0 to 1
------------------ ------------------------------------------

       IV              Equal to or greater than 4.0 to 1
------------------ ------------------------------------------

<PAGE>
                                     -23-

                                                                ANNEX 2

----------------------------------------------------------
                    Applicable Margin
                    -----------------
                       (Per annum)
----------------------------------------------------------

   Applicable       Revolving Credit Loans and Swingline
      Level                        Loans
------------------ ---------------------------------------

                    Eurodollar Loans       ABR Loans
------------------ ------------------- -------------------

        I                1.50%               0.50%
------------------ ------------------- -------------------

       II                1.75%               0.75%
------------------ ------------------- -------------------

       III               2.00%               1.00%
------------------ ------------------- -------------------

       IV                2.25%               1.25%
------------------ ------------------- -------------------Exhibit 10.4

               AMENDMENT NO. 1 TO PLEDGE AND SECURITY AGREEMENT

                  AMENDMENT NO. 1 dated as of April 2, 2004 to the Pledge and
Security Agreement (this "Amendment No. 1"), among ISP CHEMCO INC., ISP
CHEMICALS INC., ISP TECHNOLOGIES INC. and ISP MINERALS INC., each a Delaware
corporation (individually, a "Borrower", and, collectively, the "Borrowers"),
ISP CHEMCO INC., as agent for the Obligors hereunder (in such capacity, the
"Lead Borrower"), each of the SUBSIDIARY GUARANTORS party hereto from time to
time and JPMORGAN CHASE BANK, as administrative agent for the Lenders and the
LC Bankunder (and as defined in) the Credit Agreement referred to below (in
such capacity, the "Administrative Agent").

                  The Obligors, certain of the Lenders and the Administrative
Agent are parties to a Pledge and Security Agreement dated as of June 27, 2001
(as in effect immediately prior to the effectiveness of this Amendment No. 1,
the "Security Agreement"). The parties hereto wish to amend the Security
Agreement as hereinafter set forth. Accordingly, the parties hereto hereby agree
as follows:

                  Section 1. Definitions. Except as otherwise defined herein,
terms defined in the Security Agreement are used herein as defined therein.

                  Section 2. Amendments. Subject to the satisfaction of the
condition precedent specified in Section 3 hereof, the Security Agreement is
hereby amended as of the date hereof as set forth below:

1. 2.01. References in the Security Agreement to "this Agreement" (and indirect
references such as "hereunder", "hereby", "herein" and "hereof") shall be deemed
to be references to the Security Agreement as amended hereby. References in the
Security Agreement to "the Credit Agreement" (and indirect references such as
"thereunder", "thereby", "therein" and "thereof") shall be deemed to be
references to the Credit Agreement referred to below.

2. 2.02. Section 1(a) of the Security Agreement is hereby amended by deleting
the definition of "Special Reserve Sub-Account" appearing therein.

3. 2.03. Section 4.01 of the Security Agreement is hereby amended to read in
its entirety as follows:

                           "4.01 Collateral Account. The Administrative Agent
                  will cause to be established at one or more banking
                  institutions to be selected by the Administrative Agent
                  accounts (collectively, the "Collateral Account "), which
                  shall be one or more Securities Accounts and Deposit Accounts,
                  each in the name and under the sole dominion and control of
                  the Administrative Agent and, in the case of a Securities
                  Account, in respect of which the Administrative Agent is the
                  Entitlement Holder, into which there shall be deposited from
                  time to time the cash proceeds of any of the Collateral
                  (including proceeds of insurance thereon) required to be
                  delivered to the Administrative Agent pursuant hereto or that,
                  as

<PAGE>

                                      -2

         provided in Section 2.05(k) of the Credit Agreement, any of the
         Obligors are required to pledge as cash collateral or otherwise deposit
         into the Collateral Account. The Financial Assets and other property
         and balances credited to the Collateral Account from time to time shall
         constitute part of the Collateral hereunder and shall not constitute
         payment of the Secured Obligations until applied as hereinafter
         provided. Except as provided (a) in the next sentence with respect to
         an Event of Default or (b) with respect to the amount of the LC
         Exposure Sub-Account, the Administrative Agent shall remit the
         collected balance standing to the credit of the Collateral Account to
         or upon the order of the Lead Borrower shall from time to time
         instruct. However, at any time following the occurrence and during the
         continuance of an Event of Default, the Administrative Agent may (and,
         if instructed by the Required Lenders, shall) in its (or their)
         discretion apply or cause to be applied (subject to collection) the
         balance from time to time stand ing to the credit of the Collateral
         Account to the payment of the Secured Obligations in the manner
         specified in Section 5.09. The balance from time to time in the
         Collateral Account shall be subject to withdrawal and application only
         as provided herein (including this Section and Sections 4.04 and
         5.09)."

         2.04. Section 4.03 of the Security Agreement is hereby amended to read
in its as follows:

         "4.03 Investment of Balance in Collateral Account. The cash balance
         standing to the credit of the Collateral Account shall be invested from
         time to time in such Cash Equivalents as the Lead Borrower (or, after
         the occurrence and during the continuance of a Default, the
         Administrative Agent) shall determine, which Cash Equivalents shall be
         held in the name and be under the control of the Administrative Agent,
         and shall be credited to the Collateral Account, provided that at any
         time after the occurrence and during the continuance of an Event of
         Default, the Administrative Agent may (and, if instructed by the
         Required Lenders, shall) in its (or their) discretion at any time and
         from time to time elect to liquidate any such Cash Equivalents and to
         apply or cause to be applied the proceeds thereof to the payment of the
         Secured Obligations in the manner specified in Section 5.09. All
         Proceeds (including income, gain and sale proceeds) in respect of Cash
         Equivalents shall be credited to Collateral Account. All losses with
         respect to any property, including Cash Equivalents, credited to the
         Collateral Account shall be solely for account of the Obligors, and
         such losses shall be allocated first to the balance of the Collateral
         Account other than the LC Exposure Sub-Account and second to the LC
         Exposure Sub-Account."

         2.05. Section 4.05 of the Security Agreement is hereby deleted in its
entirety.

         2.06. The last sentence of Section 5.09 of the Security Agreement is
hereby amended to read in its entirety as follows:

         "Notwithstanding the foregoing, the proceeds of any cash or other
         amounts held in the LC Exposure Sub-Account pursuant to Section 4.04
         shall be applied first to

<PAGE>

                                      -3 -

         the LC Exposure outstanding from time to time and second to the other
         Secured Obligations in the manner provided above in this Section 5.09."

                  Section 3. Effectiveness. This Amendment No. 1 shall become
effective as of the date hereof upon the satisfaction of the conditions
precedent set forth in Section 5.01 of the Amended and Restated Credit Agreement
dated as of April 2, 2004 among the Obligors, the lenders party thereto and the
Administrative Agent (the "Credit Agreement").

                  Section 4. Confirmation of Security Interests. Each of the
Obligors, by its execution of this Amendment No. 1, hereby confirms and ratifies
that all of its respective obligations under the Security Agreement and the
security interests granted thereunder shall continue in full force and effect
for the benefit of the Administrative Agent and the Lenders with respect to the
Credit Agreement and the Security Agreement as amended hereby.

                  Section 5. Miscellaneous. Except as herein provided, the
Security Agreement shall remain unchanged and in full force and effect. This
Amendment No. 1 may be executed in any number of counterparts, all of which
taken together shall constitute one and the same agreement and any of the
parties hereto may execute this Amendment No. 1 by signing any such counterpart.
This Amendment No. 1 shall be governed by, and construed in accordance with, the
law of the State of New York.

<PAGE>

                                      -4-

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 1
to be duly executed and delivered as of the day and year first above written.

                                    BORROWERS
                                    ---------

                                    ISP CHEMCO INC.,
                                    Individually and as Lead Borrower

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

                                    ISP CHEMICALS INC.
                                    ISP TECHNOLOGIES INC.
                                    ISP MINERALS INC.

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>

                                      -5-

                                    SUBSIDIARY GUARANTORS
                                    ---------------------

                                    BLUEHALL INCORPORATED
                                    VERONA INC.
                                    ISP ALGINATES INC.
                                    ISP MANAGEMENT COMPANY, INC.
                                    ISP REAL ESTATE COMPANY, INC.
                                    ISP FREETOWN FINE CHEMICALS INC.
                                    ISP INVESTMENTS INC.
                                    ISP GLOBAL TECHNOLOGIES INC.
                                    ISP INTERNATONAL CORP.
                                    ISP (PUERTO RICO) INC.
                                    ISP ENVIRONENTAL SERVICES INC.

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

                                    ISP MANAGEMENT LLC
                                    By ISP Management Company, Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

                                    ISP MINERALS LLC
                                    ISP GRANULE PRODUCTS LLC
                                    By ISP Minerals Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>

                                      -6-

                                    ISP TECHNOLOGIES LLC
                                    ISP MICROCAPS (U.S.) LLC
                                    By ISP Technologies Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

                                    ISP CHEMICALS LLC
                                    By ISP Chemcals Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

                                    ISP INVESTMENTS LLC
                                    By ISP Investments Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>

                                      -7-

                                    ISP GLOBAL TECHNOLOGIES LLC
                                    By ISP Global Technologies Inc.,
                                    sole member

                                    By  /s/ Neal E. Murphy
                                        ------------------
                                    Name:  Neal E. Murphy
                                    Title:  Senior Vice President and
                                            Chief Financial Officer

<PAGE>

                                      -8-

                                    ADMINISTRATIVE AGENT
                                    --------------------

                                    JPMORGAN CHASE BANK
                                    as Administrative Agent

                                    By  /s/ Peter Dedousis
                                        ------------------
                                    Name:  Peter Dedousis
                                    Title:  Managing Director

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00066-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00066-of-00352.parquet"}]]