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Exhibit 10.5

AMENDED AND RESTATED SALE PARTICIPATION AGREEMENT

Dated as of October 15, 2004

Robert J. Zatta
c/o Rockwood Holdings, Inc.
100 Overlook Center
Princeton, NJ 08540

Dear Robert:

        You have entered into an Amended and Restated Management Stockholder's
Agreement, dated as of October 15, 2004 between Rockwood Holdings, Inc., a
Delaware corporation (the "Company"), and you (the "Stockholder's Agreement") to
amend and restate the Management Stockholder's Agreement, dated as of
September 15, 2001 between the Company and you relating to the purchase by you
from the Company of 920 shares (the "Existing Purchased Stock") of common stock,
par value $0.01 per share, of the Company (the "Common Stock") and a receipt by
you from the Company of an option to acquire 3,680 shares of Common Stock from
the Company (the "Existing Option") and to set forth the terms and conditions of
your rights as Management Stockholder with respect to the 350 additional shares
of Common Stock purchased by you under the Stockholder's Agreement, two new
options to purchase shares of Common Stock (the "New Options" and, together with
the Existing Option, the "Options") granted to you by the Company, the Existing
Purchased Stock and the Existing Option. The undersigned, KKR 1996 Fund L.P.,
KKR Partners II, L.P., KKR Millennium Fund, L.P., KKR Partners III, L.P. and KKR
European Fund, Limited Partnership (collectively, the "KKR Partners"), also have
purchased shares of Common Stock and hereby agree with you as follows, effective
upon your entering into the Stockholder's Agreement with the Company:

        1.     In the event that at any time any of the KKR Partners proposes to
sell for cash or any other consideration any shares of Common Stock owned by it,
in any transaction other than a Public Offering (as defined in the Stockholder's
Agreement) or a sale to an affiliate of KKR Partners, the KKR Partners will
notify you or your Management Stockholder's Estate or Management Stockholder's
Trust (as such terms are defined in Section 2 of the Stockholder's Agreement and
collectively with you, the "Management Stockholder Entities"), as the case may
be, in writing (a "Notice") of such proposed sale (a "Proposed Sale") and the
material terms of the Proposed Sale as of the date of the Notice (the "Material
Terms") promptly, and in any event not less than 15 calendar days prior to the
consummation of the Proposed Sale and not more than 5 calendar days after the
execution of the definitive agreement relating to the Proposed Sale, if any (the
"Sale Agreement"). If within 10 calendar days of the applicable Management
Stockholder Entities' receipt of such Notice, the KKR Partner receives from the
applicable Management Stockholder Entities, a written request (a "Request") to
include Common Stock held by the applicable Management Stockholder Entities in
the Proposed Sale (which Request shall be irrevocable unless (a) there shall be
a material adverse change in the Material Terms or (b) if otherwise mutually
agreed to in writing by the applicable Management Stockholder Entities and the
KKR Partner), the Common Stock held by you will be so included as provided
herein; provided that only one Request, which shall be executed by the
applicable Management Stockholder Entities, may be delivered with respect to any
Proposed Sale for shares of Common Stock held by the applicable Management
Stockholder Entities. Promptly after the execution of the Sale Agreement, the
KKR Partner will furnish the applicable Management Stockholder Entities with a
copy of the Sale Agreement, if any.

        2.     (a) The maximum number of shares of Common Stock which the
applicable Management Stockholder Entities will be permitted to include in a
Proposed Sale pursuant to a Request will be the number of shares of Common Stock
then held by the Management Stockholder Entities, including all shares of Common
Stock which the Management Stockholder Entities are then entitled to acquire
under unexercised Options, to the extent then exercisable or would become
exercisable as a result of

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the consummation of the Proposed Sale, multiplied by a fraction, the numerator
of which is the number of shares of Common Stock being sold by KKR Partners and
any investment partnerships and investment limited liability companies
affiliated with KKR Partners and the denominator of which is the aggregate
number of shares of Common Stock owned by KKR Partners and any investment
partnerships and investment limited liability companies affiliated with KKR
Partners.

        (b)   If one or more holders of shares of Common Stock who have been
granted the same rights granted to the Management Stockholder Entities hereunder
elect not to include the maximum number of shares of Common Stock which such
holders would have been permitted to include in a Proposed Sale (the "Eligible
Shares"), KKR Partners, or such remaining holders of shares of Common Stock, or
any of them, may sell in the Proposed Sale a number of additional shares of
Common Stock owned by any of them equal to their pro rata portion of the number
of Eligible Shares not included in the Proposed Sale, based on the relative
number of shares of Common Stock then held by each such holder, and such
additional shares of Common Stock which any such holder or holders propose to
sell shall not be included in any calculation made pursuant to the first
sentence of Section 2(a) above for the purpose of determining the number of
shares of Common Stock which the Management Stockholder Entities will be
permitted to include in a Proposed Sale. KKR Partners or any of them may sell in
the Proposed Sale additional shares of Common Stock owned by any of them equal
to any remaining Eligible Shares which will not be included in the Proposed Sale
pursuant to the foregoing.

        3.     Except as may otherwise be provided herein, shares of Common
Stock subject to a Request will be included in a Proposed Sale on the same terms
and subject to the same conditions applicable to the shares of Common Stock
which the KKR Partner proposes to sell in the Proposed Sale. Such terms and
conditions shall include, without limitation: the pro rata reduction of the
number of shares of Common Stock to be included in the Proposed Sale if required
by the party proposing such Sale; the sale price; the payment of fees,
commissions and expenses; the provision of, and representation and warranty as
to, information reasonably requested by the KKR Partner covering matters
regarding your ownership of shares; and the provision of requisite
indemnification; provided that, any indemnification provided by the applicable
Management Stockholder Entities shall be pro rata in proportion with the number
of shares of Common Stock to be sold.

        4.     Upon delivering a Request, the applicable Management Stockholder
Entities will, if requested by the KKR Partner, execute and deliver a custody
agreement and power of attorney in form and substance satisfactory to the KKR
Partner with respect to the shares of Common Stock which are to be sold by the
applicable Management Stockholder Entities pursuant hereto (a "Custody Agreement
and Power of Attorney"). The Custody Agreement and Power of Attorney will
provide, among other things, that the applicable Management Stockholder Entities
will deliver to and deposit in custody with the custodian and attorney-in-fact
named therein a certificate or certificates representing such shares of Common
Stock (duly endorsed in blank by the registered owner or owners thereof) and
irrevocably appoint said custodian and attorney-in-fact as the applicable
Management Stockholder Entities' agent and attorney-in-fact with full power and
authority to act under the Custody Agreement and Power of Attorney on behalf of
the applicable Management Stockholder Entities with respect to the matters
specified therein.

        5.     The Management Stockholder Entities' right pursuant hereto to
participate in a Proposed Sale shall be contingent on the Management Stockholder
Entities' strict compliance with each of the provisions hereof and the
Management Stockholder Entities' respective willingness to execute such
documents in connection therewith as may be reasonably requested by any KKR
Partner.

        6.     In the event of a Proposed Sale pursuant to Section 1 hereof of a
majority of the shares of Common Stock held by the KKR Partners, the KKR
Partners may elect, by so specifying in the Notice, to require the applicable
Management Stockholder Entities to participate in such Proposed Sale to the

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same extent calculated pursuant to Section 2(a) above, in accordance with the
terms and provisions of Sections 3 and 4 hereof.

        7.     The obligations of KKR Partners hereunder shall extend only to
the Management Stockholder Entities, and no other successors or assigns of the
Management Stockholder Entities shall have any rights pursuant hereto.

        8.     This Agreement shall terminate and be of no further force and
effect on the fifth anniversary of the first occurrence of a Public Offering (as
defined in the Stockholder's Agreement).

        9.     All notices and other communications provided for herein shall be
in writing and shall be deemed to have been duly given when delivered to the
party to whom it is directed:

If to KKR Partners, to it at the following address:

c/o Kohlberg Kravis Roberts & Co. L.P.
9 West 57th Street
New York, New York 10019
Attn: Brian Carroll

with a copy to:

Simpson Thacher & Bartlett LLP
425 Lexington Avenue
New York, NY 10017
Attn: Roxane F. Reardon, Esq.

        If to you, to you at the address first set forth above herein;

        If to your Management Stockholder's Estate or Management Stockholder's
Trust, at the address provided to the Company by such entity or at such other
address as such entity shall have specified by notice in writing delivered to
the other parties to this Agreement by certified mail.

        10.   The laws of the State of Delaware (or if the Company
reincorporates in another state, of that state) shall govern the interpretation,
validity and performance of the terms of this Agreement. No suit, action or
proceeding with respect to this Agreement may be brought in any court or before
any similar authority other than in a court of competent jurisdiction in the
State of Delaware (or if the Company reincorporates in another state, of that
state), as the KKR Partners may elect in their sole discretion, and you hereby
submit to the non-exclusive jurisdiction of such courts for the purpose of such
suit, proceeding or judgment. You hereby irrevocably waive any right which you
may have had to bring such an action in any other court, domestic or foreign, or
before any similar domestic or foreign authority.

        11.   If any KKR Partner transfers its interest in the Company to an
affiliate of KKR Partners, such affiliate shall assume the obligations hereunder
of such KKR Partner.

        It is the understanding of the undersigned that you are aware that no
Proposed Sale presently is contemplated and that such a sale may never occur.

        If the foregoing accurately sets forth our agreement, please acknowledge
your acceptance thereof in the space provided below for that purpose.

        Very truly yours,
 
 
 
 
KKR 1996 Fund L.P.         By:   KKR Associates 1996 L.P.
its General Partner              

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By:
 
KKR 1996 GP LLC,
its General Partner
 
 
 
 
By:
 
/s/ PERRY GOLKIN

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General Partner
 
 
 
 
KKR PARTNERS II, L.P.
 
 
 
 
By:
 
KKR Associates L.P.,
General Partner
 
 
 
 
By:
 
/s/ PERRY GOLKIN

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General Partner
 
 
 
 
KKR MILLENNIUM FUND, L.P.
        as General Partner
 
 
 
 
By:
 
KKR MILLENNIUM GP LLC
as General Partner
 
 
 
 
By:
 
/s/ PERRY GOLKIN

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Member
 
 
 
 
KKR PARTNERS III, L.P.
 
 
 
 
By:
 
KKR GP III, LLC,
its General Partner
 
 
 
 
By:
 
/s/ PERRY GOLKIN

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Member
 
 
 
 
KKR EUROPEAN FUND, LIMITED PARTNERSHIP
 
 
 
 
By:
 
KKR ASSOCIATES EUROPE, LIMITED PARTNERSHIP, as General Partner
 
 
 
 
By:
 
KKR EUROPE LIMITED,
as General Partner
 
 
 
 
By:
 
/s/ PERRY GOLKIN

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Director
Accepted and agreed to:
 
 
 
 
By:
 
/s/ ROBERT J. ZATTA

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Name: Robert J. Zatta
 
 
 
 

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Exhibit 10.5

AMENDED AND RESTATED SALE PARTICIPATION AGREEMENT