CHANGE IN CONTROL AGREEMENT

EXHIBIT 10(bbb)

CHANGE IN CONTROL AGREEMENT

THIS AGREEMENT, dated June 18, 2004, between QUAKER CHEMICAL CORPORATION, a Pennsylvania corporation (the “Company”), and Rex Curtis (the “Manager”),

W I T N E S S E T H   T H A T

WHEREAS, the Board of Directors of the Company has determined that it is in the best interests of the Company and its shareholders that the Company and its subsidiaries be able to attract, retain, and motivate highly qualified management personnel and, in particular, that they be assured of continuity of management in the event of any actual or threatened change in control of the Company; and

WHEREAS, the Board of Directors of the Company believes that the execution by the Company of change in control agreements with certain management personnel, including the Manager, is an important factor in achieving this desired end;

NOW, THEREFORE, IN CONSIDERATION of the mutual obligations and agreements contained herein and intending to be legally bound hereby, the Manager and the Company agree as follows:

1. Term of Agreement.

This Agreement shall become effective on May 14, 2004 (the “Effective Date”), and shall continue in effect through December 31, 2005; provided, however, that the term of this Agreement shall automatically be extended for one additional year beyond December 31, 2005, and successive one year periods thereafter, unless, not later than eighteen (18) months preceding the calendar year in which the term would otherwise automatically extend, the Company shall have given written notice to the Manager of intention not to extend this Agreement for an additional year, in which event this Agreement shall continue in effect until December 31 of the calendar year immediately preceding the calendar year in which the term would have otherwise automatically extended. Notwithstanding any such notice not to extend, if a Change in Control (as defined in Section 2) occurs during the original or extended term of this Agreement, this Agreement shall remain in effect after a Change in Control until all obligations of the parties hereto under this Agreement shall have been satisfied.

2. Change in Control.

As used in this Agreement, a “Change in Control” of the Company shall be deemed to have occurred if:

(a) Any person (a “Person”), as such term is used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (other than (i) the Company and/or its wholly owned subsidiaries; (ii) any ESOP or other employee benefit plan of the Company and any trustee or other fiduciary in such capacity holding securities under such plan;

(iii) any corporation owned, directly or indirectly, by the shareholders of the Company in substantially the same proportions as their ownership of stock of the Company; or (iv) any other Person who, within the one year prior to the event which would otherwise be a Change in Control, is an executive officer of the Company or any group of Persons of which he voluntarily is a part), is or becomes the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing 30% or more of the combined voting power of the Company’s then outstanding securities or such lesser percentage of voting power, but not less than 15%, as determined by the members of the Board of Directors of the Company who are independent directors (as defined in the New York Stock Exchange, Inc. Listed Company Manual); provided, however, that a Change in Control shall not be deemed to have occurred under the provisions of this subsection (a) by reason of the beneficial ownership of voting securities by members of the Benoliel family (as defined below) unless and until the beneficial ownership of all members of the Benoliel family (including any other individuals or entities who or which, together with any member or members of the Benoliel family, are deemed under Sections 13(d) or 14(d) of the Exchange Act to constitute a single Person) exceeds 50% of the combined voting power of the Company’s then outstanding securities;

(b) During any two-year period after the Effective Date, Directors of the Company in office at the beginning of such period plus any new Director (other than a Director designated by a Person who has entered into an agreement with the Company to effect a transaction within the purview of subsections (a) or (c)) whose election by the Board of Directors of the Company or whose nomination for election by the Company’s shareholders was approved by a vote of at least two-thirds of the Directors then still in office who either were Directors at the beginning of the period or whose election or nomination for election was previously so approved shall cease for any reason to constitute at least a majority of the Board;

(c) The consummation of (i) any consolidation or merger of the Company in which the Company is not the continuing or surviving corporation or pursuant to which the Company’s voting common shares (the “Common Shares”) would be converted into cash, securities, and/or other property, other than a merger of the Company in which holders of Common Shares immediately prior to the merger have the same proportionate ownership of voting shares of the surviving corporation immediately after the merger as they had in the Common Shares immediately before; or (ii) any sale, lease, exchange, or other transfer (in one transaction or a series of related transactions) of all or substantially all the assets or earning power of the Company; or

(d) The Company’s shareholders or the Company’s Board of Directors shall approve the liquidation or dissolution of the Company.

As used in this Agreement, “members of the Benoliel family” shall mean Peter A. Benoliel, his wife and children and their respective spouses and children, and all trusts created by or for the benefit of any of them.

3. Entitlement to Change in Control Benefits; Certain Definitions.

The Manager shall be entitled to the benefits provided in this Agreement in the event the Manager’s employment with the Company or its affiliates is terminated under the circumstances

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described in (a) or (b) below (a “Covered Termination”), provided the Manager executes and does not revoke a Release (as defined below).

(a) A Covered Termination shall have occurred within the meaning of this subsection (a) in the event the Manager’s employment with the Company or its affiliates is terminated within two (2) years following a Change in Control by:

(b) A Covered Termination shall have occurred within the meaning of this subsection (b) in the event the Manager’s employment with the Company or its affiliates is terminated by the Company or its affiliates without Cause within six months prior to a Change in Control and the Manager reasonably demonstrates after such Change in Control that such termination was at the request or suggestion of any individual or entity who or which has taken steps reasonably calculated to effect such Change in Control.

The Manager shall have no rights to any payments or benefits under this Agreement in the event the Manager’s employment with the Company and its affiliates is terminated (i) as a result of death or Disability (as defined below), or (ii) by the Company or its affiliates for Cause. Except as provided in subsection (b), in the event the Manager’s employment is terminated for any reason prior to a Change in Control, the Manager shall have no rights to any payments or benefits under this Agreement and, after any such termination, this Agreement shall be of no further force or effect.

“Cause” shall mean (i) the Manager’s willful and material breach of the employment agreement, if any, between the Manager and the Company (after having received notice thereof and a reasonable opportunity to cure or correct), (ii) dishonesty, fraud, willful malfeasance, gross negligence, or other gross misconduct, in each case relating to the performance of the Manager’s employment with the Company or its affiliates which is materially injurious to the Company, or (iii) conviction of or plea of guilty to a felony, such Cause to be determined, in each case, by a resolution approved by at least two-thirds of the Directors of the Company after having afforded the Manager a reasonable opportunity to appear before the Board of Directors of the Company and present his position.

“Disability” shall mean: (i) a physical or mental disability which, at least twenty-six (26) weeks after its commencement, is determined to be total and permanent by a physician selected by the Company or its insurers and reasonably acceptable to the Manager or the Manager’s legal representative, or (ii) if the Company then has in effect a long-term disability plan covering employees generally, including the Manager, the definition of covered total and permanent “disability” set forth in such plan.

“Good Reason” shall mean any of the following actions without the Manager’s consent, other than due to the Manager’s death or Disability: (i) any reduction in the Manager’s base salary from that provided immediately before the Covered Termination or, if higher, immediately before the Change in Control; (ii) any reduction in the Manager’s bonus opportunity (including

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cash and noncash incentives) or increase in the goals or standards required to accrue that opportunity, as compared to the opportunity and goals or standards in effect immediately before the Change in Control; (iii) a material adverse change in the nature or scope of the Manager’s authorities, powers, functions, or duties from those in effect immediately before the Change in Control; (iv) a reduction in the Manager’s benefits from those provided immediately before the Change in Control, disregarding any reduction under a plan or program covering employees generally that applies to all employees covered by the plan or program; or (v) the Manager being required to accept a primary employment location which is more than twenty-five (25) miles from the location at which he primarily was employed during the ninety (90) day period prior to a Change in Control.

“Release” shall mean a release (in a form satisfactory to the Company) of any and all claims against the Company and all related parties with respect to all matters arising out of the Manager’s employment by the Company and its affiliates, or the termination thereof (other than claims for any entitlements under the terms of this Agreement or under any plans or programs of the Company under which the Manager has accrued a benefit). Notwithstanding any provision of this Agreement to the contrary, the Manager shall not be entitled to any payments or benefits under this Agreement unless the Manager executes and does not revoke a Release.

4. Severance Allowance.

(a) Amount of Severance Allowance. In the event of a Covered Termination, except as provided in Section 6, the Company shall pay or cause to be paid to the Manager in cash a severance allowance (the “Severance Allowance”) equal to 1.5 times the sum of the amounts determined in accordance with the following paragraphs (i) and (ii):

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In no event shall any retention bonus or change in control or success fee be taken into account when determining the amount of the Severance Allowance hereunder.

(b) Payment of Severance Allowance. The Severance Allowance shall be paid to the Manager (i) in a lump sum within sixty (60) days after the date of any termination of the Manager covered by Section 3(a), or (ii) in the case of a termination described in Section 3(b), in a lump sum within sixty (60) days after the date of the Change in Control giving rise to such Covered Termination.

5. Outplacement and Welfare Benefits.

(a) Outplacement. Subject to Section 6, for a period of one year following a Covered Termination of the Manager (or the Change in Control resulting in a Covered Termination, if later), the Company shall make or cause to be made available to the Manager, at its expense, outplacement counseling and other outplacement services comparable to those available for the Company’s senior managers prior to the Change in Control.

(b) Welfare Benefits. Subject to Section 6, for a period of 18 months following a Covered Termination of the Manager (or the Change in Control resulting in a Covered Termination, if later), the Manager and the Manager’s dependents shall be entitled to participate in the Company’s life, medical, and dental insurance plans at the Company’s expense, in accordance with the terms of such plans at the time of such Covered Termination as if the Manager were still employed by the Company or its affiliates under this Agreement. If, however, life, medical, or dental insurance benefits are not paid or provided under any such plan to the Manager or his dependents because the Manager is no longer an employee of the Company or its subsidiaries, the Company itself shall, to the extent necessary, pay or otherwise provide for such benefits to the Manager and his dependents.

6. Effect of Other Employment.

In the event the Manager becomes employed (as defined below) during the period with respect to which benefits are continuing pursuant to Section 5: (a) the Manager shall notify the Company not later than the day such employment commences; and (b) the benefits provided for in Section 5 shall terminate as of the date of such employment. For the purposes of this Section 6, the Manager shall be deemed to have become “employed” by another entity or person only if the Manager becomes essentially a full-time employee of a person or an entity (not more than 30% of which is owned by the Manager and/or members of his family); and the Manager’s “family” shall mean his parents, his siblings and their spouses, his children and their spouses, and the Manager’s spouse and her parents and siblings. Nothing herein shall relieve the Company of its obligations for compensation or benefits accrued up to the time of termination provided for herein.

7. Other Payments and Benefits.

Within (30) business days after the Covered Termination (or the Change in Control resulting in a Covered Termination, if later), the Company shall pay or cause to be paid to the Manager the aggregate of: (a) the Manager’s earned but unpaid base salary through the Covered Termination at the rate in effect on the date of the Covered Termination, or if higher, at the rate

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in effect at any time during the 90-day period preceding the Change in Control; (b) any unpaid bonus or annual incentive payable to the Manager in respect of the calendar year ending prior to the Covered Termination; (c) the pro rata portion of any and all unpaid bonuses and annual incentive awards for the calendar year in which the Covered Termination occurs, said pro rata portion to be calculated on the fractional portion (the numerator of said fraction being the number of days between January 1 and the date of the Covered Termination, and the denominator of which is 365) of the amount of bonuses or awards which would have been payable had the Covered Termination not occurred in such calendar year; and (d) the pro rata portion of any and all awards under the Company’s long term incentive plan for the performance period(s) in which the Covered Termination occurs, said pro rata portion to be calculated on the fractional portion (the numerator of said fraction being the number of days between the first day of the applicable performance period and the date of the Covered Termination, and the denominator of which is the total number of days in the applicable performance period) of the amount of the award which would have been payable had (i) the Covered Termination not occurred, and (ii) the target level of performance been achieved for the applicable performance period. The Manager shall be entitled to receive any other payments or benefits that the Manager is entitled to pursuant to the express terms of any compensation or benefit plan or arrangement of the Company or any of its affiliates; provided that the Severance Allowance (x) shall be in lieu of any severance payments to which the Manager might otherwise be entitled under the terms of any severance pay plan, policy, or arrangement maintained by the Company or the employment agreement, if any, between the Manager and the Company, and (y) shall be credited against any severance payments to which the Manager may be entitled by statute.

8. Death After Covered Termination.

In the event the Manager dies after a Covered Termination occurs, (a) any payments due to the Manager under Section 4 and the first sentence of Section 7 and not paid prior to the Manager’s death shall be made to the person or persons who may be designated by the Manager in writing or, in the event he fails to so designate, to the Manager’s personal representatives, and (b) the Manager’s dependents shall be eligible for the welfare benefits described in Section 5(b).

9. Confidentiality and Noncompetition.

(a) Confidential Information. The Manager acknowledges that information concerning the method and conduct of the Company’s (and any affiliate’s) business, including, without limitation, strategic and marketing plans, budgets, corporate practices and procedures, financial statements, customer and supplier information, formulae, formulation information, application technology, manufacturing information, and laboratory test methods and all of the Company’s (and any affiliate’s) manuals, documents, notes, letters, records, and computer programs (“Proprietary Business Information”), are the sole and exclusive property of the Company (and/or the Company’s affiliates, as the case may be) and are likely to constitute, contain or reveal trade secrets (“Trade Secrets”) of the Company (and/or the Company’s affiliate’s, as the case may be). The term “Trade Secrets” as used herein does not include Proprietary Business Information that is known or becomes known to the public through no act or failure to act on the part of the Manager, or which can be clearly shown by written records to have been known by the Manager prior to the commencement of his employment with the Company.

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(b) Noncompetition. The Manager agrees that during his employment and for a period of one (1) year thereafter, regardless of the reason for the termination of the Manager’s employment, he will not:

(c) Severability. The Manager acknowledges and agrees that all of the foregoing restrictions are reasonable as to the period of time and scope. However, if any paragraph, sentence, clause, or other provision is held invalid or unenforceable by a court of competent and relevant jurisdiction, such provision shall be deemed to be modified in a manner consistent with the intent of such original provision so as to make it valid and enforceable, and this Agreement and the application of such provision to persons and circumstances other than those with respect to which it would be invalid or unenforceable shall not be affected thereby.

(d) Remedies. The Manager agrees and recognizes that in the event of a breach or threatened breach of the provisions of the restrictive covenants contained in this Section 9, the Company may suffer irreparable harm, and monetary damages may not be an adequate remedy.

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Therefore, if any breach occurs or is threatened, the Company shall be entitled to seek equitable remedies, including injunctive relief in any court of applicable jurisdiction notwithstanding the provisions of Section 11. In the event of any breach of the restrictive covenant contained in this Section 9, the term of the restrictive covenant specified herein shall be extended by a period of time equal to that period beginning on the date such violation commenced and ending when the activities constituting such violation cease. Furthermore, if a court or arbitration panel determines that the Manager has breached any of the provisions of this Section 9, the Company’s obligations to pay amounts and continue the benefits under this Agreement to the Manager (and his dependents) shall immediately terminate.

10. Set-Off Mitigation.

Except as provided in Section 6, the Company’s obligation to make the payments provided for in this Agreement and otherwise to perform its obligations hereunder shall not be affected by any set-off, counterclaim, recoupment, defense, or other claim, right, or action which the Company may have against the Manager or others. In no event shall the Manager be obligated to seek other employment or take any other action by way of mitigation of the amounts payable to the Manager under any of the provisions of this Agreement.

11. Arbitration: Costs and Expenses of Enforcement.

(a) Arbitration. Except as otherwise provided in Sections 9(d) and 12, any controversy or claim arising out of or relating to this Agreement or the breach thereof which cannot promptly be resolved by the parties shall be promptly submitted to and settled exclusively by arbitration in the City of Philadelphia, Pennsylvania, in accordance with the laws of the Commonwealth of Pennsylvania by three arbitrators, one of whom shall be appointed by the Company, one by the Manager, and the third of whom shall be appointed by the first two arbitrators. The arbitration shall be conducted in accordance with the rules of the American Arbitration Association, except with respect to the selection of arbitrators which shall be as provided in this Section 11. Judgment upon the award rendered by the arbitrators may be entered in any court having jurisdiction thereof.

(b) Costs and Expenses. In the event that it shall be necessary or desirable for the Manager to retain legal counsel and/or incur other costs and expenses in connection with the enforcement of any and all of his rights under this Agreement, the Company shall pay (or the Manager shall be entitled to recover from the Company, as the case may be) his reasonable attorneys’ fees and costs and expenses in connection with the enforcement of his said rights (including those incurred in or related to any arbitration proceedings provided for in subsection (a) and the enforcement of any arbitration award in court), regardless of the final outcome.

12. Limitation on Payment Obligation.

(a) For purposes of this Section 12, all terms capitalized but not otherwise defined herein shall have the meanings as set forth in Section 280G of the Internal Revenue Code of 1986, as amended, together with any applicable regulations thereunder (the “Code”). In addition:

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any stock option rights, stock grants, and other cash and noncash compensation amounts that are treated as payments under either such section) and not excluded under Section 280G(b)(4)(A) or Section 280G(b)(6) of the Code;

(b) Notwithstanding any other provision of this Agreement, each Parachute Payment to be made to or for the benefit of the Manager, whether pursuant to this Agreement or otherwise, with respect to a Change in Control shall be reduced if and to the extent necessary so that the aggregate Present Value of all such Parachute Payments shall be at least one dollar ($1.00) less than the greater of (i) three times the Manager’s Base Amount and (ii) the aggregate Reasonable Compensation allocable to such Parachute Payments. Unless otherwise agreed by the Manager and the Company, any reduction in Parachute Payments caused by reason of this subsection (b) shall be made proportionately with respect to each such Parachute Payment.

This subsection (b) shall be interpreted and applied to limit the amounts otherwise payable to the Manager under this Agreement or otherwise only to the extent required to avoid any material risk of the imposition of excise taxes on the Manager under Section 4999 of the Code or the disallowance of a deduction to the Company under Section 280G(a) of the Code. In the making of any such interpretation and application, the Manager shall be presumed to be a disqualified individual for purposes of applying the limitations set forth in this subsection (b) without regard to whether or not the Manager meets the definition of disqualified individual set forth in Section 280G(c) of the Code. In the event that the Manager and the Company are unable to agree as to the application of this subsection (b), the Company’s independent auditors shall select independent tax counsel to determine the amount of such limits. Such selection of tax counsel shall be subject to the Manager’s consent, provided that the Manager shall not unreasonably withhold his consent. The determination of such tax counsel under this Section 12 shall be final and binding upon the Manager and the Company.

(c) Notwithstanding any other provision of this Agreement, no payment shall be made hereunder to or for the benefit of the Manager if and to the extent that such payments are determined to be illegal.

13. Notices.

Any notices, requests, demands, and other communications provided for by this Agreement shall be sufficient if in writing, and if hand delivered or if sent by registered or certified mail, if to the Manager, at the last address he had filed in writing with the Company or if to the Company, at its principal executive offices. Notices, requests, etc. shall be effective when actually received by the addressee or at such address.

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14. Withholding.

Notwithstanding any provision of this Agreement to the contrary, the Company may, to the extent required by law, withhold applicable Federal, state and local income and other taxes from any payments due to the Manager hereunder.

15. Assignment and Benefit.

(a) This Agreement is personal to the Manager and shall not be assignable by the Manager, by operation of law, or otherwise without the prior written consent of the Company otherwise than by will or the laws of descent and distribution. This Agreement shall inure to the benefit of and be enforceable by the Manager’s heirs and legal representatives.

(b) This Agreement shall inure to the benefit of and be binding upon the Company and its successors and assigns, including, without limitation, any subsidiary of the Company to which the Company may assign any of its rights hereunder; provided, however, that no assignment of this Agreement by the Company, by operation of law, or otherwise shall relieve it of its obligations hereunder except an assignment of this Agreement to, and its assumption by, a successor pursuant to subsection (c).

(c) The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation operation of law, or otherwise) to all or substantially all of the business and/or assets of the Company to assume expressly and agree to perform this Agreement in the same manner and to the same extent that the Company would be required to perform it if no such succession had taken place, but, irrespective of any such assignment or assumption, this Agreement shall inure to the benefit of and be binding upon such a successor. As used in this Agreement, “Company” shall mean the Company as hereinbefore defined and any successor to its business and/or assets as aforesaid.

16. Governing Law.

The provisions of this Agreement shall be construed in accordance with the laws of the Commonwealth of Pennsylvania without reference to principles of conflicts of laws.

17. Entire Agreement.

This Agreement represents the entire agreement and understanding of the parties with respect to the subject matter hereof, and it may not be altered or amended except by an agreement in writing executed by the Company and the Manager.

18. No Waiver.

The failure to insist upon strict compliance with any provision of this Agreement by any party shall not be deemed to be a waiver of any future noncompliance with such provision or of noncompliance with any other provision.

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19. Severability.

In the event that any provision or portion of this Agreement shall be determined to be invalid or unenforceable for any reason, the remaining provisions of this Agreement shall be unaffected thereby and shall remain in full force and effect.

20. Indemnification.

The Company shall defend and hold the Manager harmless to the fullest extent permitted by applicable law in connection with any claim, action, suit, investigation or proceeding arising out of or relating to performance by the Manager of services for, or action of the Manager as a director, officer or employee of the Company or any parent, subsidiary or affiliate of the Company, or of any other person or enterprise at the Company’s request. Expenses incurred by the Manager in defending a claim, action, suit or investigation or criminal proceeding shall be paid by the Company in advance of the final disposition thereof upon the receipt by the Company of an undertaking by or on behalf of the Manager to repay said amount unless it shall ultimately be determined that the Manager is entitled to be indemnified hereunder; provided, however, that this shall not apply to a nonderivative action commenced by the Company against the Manager.

IN WITNESS WHEREOF, the Manager has hereunto set his hand and, pursuant to the authorization from its Board of Directors, the Company has caused these presents to be executed in its name and on its behalf and attested by its Secretary or Assistant Secretary, all as of the day and year first above written.

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