<PAGE>   1
             AMENDED AND RESTATED GUARANTY AND SURETYSHIP AGREEMENT

                  THIS AMENDED AND RESTATED GUARANTY AND SURETYSHIP AGREEMENT,
made as of December 11, 2000 (herein, together with all amendments and
supplements hereto, called this "Guaranty"), by SYBRON INTERNATIONAL
CORPORATION, f/k/a Sybron Acquisition Company, a Wisconsin corporation, d/b/a
Apogent Technologies (herein, together with any corporation succeeding thereto
by consolidation, merger or acquisition of its assets substantially as an
entirety, called "Guarantor"), having its principal office at 10 Pleasant
Street, Suite 300, Portsmouth, New Hampshire 03801, to CORPORATE PROPERTY
ASSOCIATES 8, L.P., A DELAWARE LIMITED PARTNERSHIP, a Delaware limited
partnership and CORPORATE PROPERTY ASSOCIATES 7 - A CALIFORNIA LIMITED
PARTNERSHIP, a California limited partnership (herein, together with their
successors and assigns, collectively called "Landlord"), each having an address
c/o W. P. Carey & Co., LLC, 50 Rockefeller Plaza, 2nd Floor, New York, New York
10020.

                                   WITNESSETH:

                  WHEREAS, Landlord, as lessor, has entered into (a) a Lease
Agreement made as of December 21, 1988 (the "Barnstead Lease") with Barnstead
Thermolyne Corporation ("Barnstead"), as lessee, covering certain real property
located in Dubuque, Iowa, as more particularly described therein; (b) a Lease
Agreement made as of December 21, 1988 (the "Erie Lease") with Erie Scientific
Company ("Erie"), as lessee, covering certain premises located in Portsmouth,
New Hampshire; and (c) a Lease Agreement made as of December 21, 1988 (the
"Nalge Lease") with Nalge Company ("Nalge"), as lessee, covering certain
premises located in Penfield, New York (collectively, the Barnstead Lease, the
Erie Lease and the Nalge Lease, all as may be amended or modified from time to
time, are referred to herein as the "Leases"; and Barnstead, Erie and Nalge are
hereinafter referred to collectively as the "Tenants");

                  WHEREAS, simultaneously with the execution and delivery of
this Guaranty, Landlord and each of the Tenants have entered into an Amendment
of the Lease Agreement dated as of the date hereof (collectively, the "Lease
Amendments");

                  WHEREAS, as a material inducement to Landlord to enter into
the Leases, Guarantor made for the benefit of Landlord that certain Guaranty and
Suretyship Agreement made as of December 21, 1988, guaranteeing among other
things, all of Tenants obligations under the Leases (the "Original Guaranty");

                  WHEREAS, Barnstead, Erie and Nalge are indirectly wholly-
owned subsidiaries of Guarantor;
<PAGE>   2

                  WHEREAS, the execution and delivery of this Guaranty by
Guarantor is a material inducement to Landlord to enter into the Lease
Amendments and Guarantor will substantially benefit from the execution of the
Lease Amendments; and

                 WHEREAS, the parties hereto wish to amend and restate the
 Original Guaranty in its entirety in order to correctly reflect the revised
 terms of the Original Guaranty.

                 NOW, THEREFORE, in consideration of the execution and delivery
 of the Lease Amendments and for other good and valuable consideration, the
 receipt and sufficiency of which are hereby acknowledged, Guarantor, intending
 to be legally bound, covenants and agrees with Landlord as follows:

                 1. Guarantor unconditionally and irrevocably guarantees to
Landlord, as to each Lease, that (a) all Rent (as defined in such Lease),
purchase prices and all other sums stated in such Lease to be payable by the
Tenant thereunder, whether due by acceleration or otherwise, including costs and
expenses of collection (collectively, the "Monetary Obligations") will be
promptly paid in full when due, in accordance with the provisions thereof, and
(b) such Tenant will perform and observe each and every covenant, agreement,
term and condition in such Lease to be performed or observed by such Tenant,
including contingent obligations to offer to purchase the Leased Premises and to
pay the agreed purchase price therefor as provided in the Lease (collectively,
the "Performance Obligations"). If for any reason any Monetary Obligations shall
not be paid promptly when due, Guarantor shall, immediately upon demand, pay the
same to Landlord with interest due thereon as stated in the Lease. If for any
reason such Tenant shall fail to perform or observe any Performance Obligations,
Guarantor shall, immediately upon demand, perform and observe the same or cause
the same to be performed or observed. In addition to the foregoing, Guarantor
hereby becomes surety to Landlord for the due and punctual payment and
performance of the Monetary Obligations and the Performance Obligations and
Guarantor hereby waives all defenses of any nature that may be available to
Guarantor as a surety and guarantor other than the defenses of payment of the
Monetary Obligations and performance of the Performance Obligations.

                 2. Landlord may enforce this Guaranty without first having
recourse against any Tenant, or exhausting its rights or remedies under any
Lease; provided, however, that nothing herein shall prohibit Landlord from
exercising its rights against Guarantor and any or all of the Tenants
simultaneously, jointly or severally. This Guaranty and the obligations of
Guarantor hereunder are direct, continuing, unconditional, irrevocable and
absolute; this Guaranty constitutes the agreement to pay money and to act in the
first instance and is not to be construed as a contract of indemnity or as a
guaranty of collectibility. This Guaranty is made expressly for the benefit of
Landlord and each Lender from time to time, and this Guaranty, the rights of
Landlord and Lender hereunder and any partial interest herein may be assigned in
whole or in part from time to time by Landlord or Lender, whether directly or by
way of a grant of security herein, without the consent of Guarantor. Any Lender,
whether or not such Lender is an assignee, may enforce any and all of the terms
hereof as though such Lender were a party hereto. No action or failure to act on
the part of Guarantor shall adversely affect or limit in any way the rights
hereunder of Landlord, any Lender or any such assignee. No such assignment shall
relieve Guarantor of its obligations hereunder or constitute an assumption of
any such obligation on the part of any such assignee.



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<PAGE>   3

                 3. The obligations, covenants, agreements and duties of
Guarantor under this Guaranty shall in no way be discharged, affected or
impaired by any of the following:

                           (a) the waiver by Landlord of the performance or
                  observance by any Tenant or any other party of any of the
                  agreements, covenants, terms or conditions contained in any
                  Lease;

                           (b) the extension, in whole or in part, of the time
                  for payment by any Tenant of any sums owing or payable under
                  any Lease, or of any other sums or obligations under or
                  arising out of or on account of any Lease, or the renewal or
                  extension of any Lease;

                           (c) any sublease by any Tenant to any other Person
                  as defined in such Tenant's respective Lease;

                           (d) any assumption by any party of any Tenant's
                  obligations under, or any Tenant's assignment of any of its
                  interests in, the Lease to which it is a party (provided,
                  however, if (i) any Tenant shall assign its Lease to an entity
                  with a rating on its publicly traded unsecured senior debt of
                  "Baa" or better from Moody's Investors Services, Inc. or with
                  a comparable rating by Standard & Poor's Corporation, in
                  accordance with the provisions of Paragraph 17 of such Lease,
                  (ii) such assignee shall expressly assume all obligations of
                  such Tenant under the Lease, which arise on or after the date
                  of such assignment, by written instrument of assumption
                  delivered to Landlord at the time of such assignment with a
                  duplicate original delivered to Lender which instrument
                  incorporates no collateral matters and which does not alter
                  the obligations under the Lease and (iii) such Tenant has
                  fulfilled all its obligations to Landlord under the Lease
                  which arose prior to the date of such assignment, then this
                  Guaranty shall terminate as to such Tenant; provided, however,
                  that this Guaranty shall not terminate with respect to any
                  violation of the Environmental Laws which arises prior to the
                  date of such assignment unless such assignee assumes all
                  obligations of such Tenant under the Lease with respect to any
                  violation of the Environmental Laws actual or contingent,
                  which arise prior to the date of such assignment, and
                  provided, further, that if the assignee described in clause
                  (i) above is also a Tenant Affiliate (as such term is defined
                  in the Lease), this Guaranty shall not terminate as to such
                  Tenant);

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<PAGE>   4

                           (e) the modification or amendment (whether material
                  or otherwise) of any provision of any Lease and Guarantor
                  hereby consents to any such modifications and amendments and
                  to any future terms or agreements heretofore or hereafter made
                  by Landlord and any Tenant in accordance with the terms of
                  such Lease;

                           (f) any failure, omission or delay on the part of
                  Landlord to enforce, assert or exercise any right, power or
                  remedy conferred on or available to Landlord in or by any
                  Lease or this Guaranty, or any action on the part of Landlord
                  granting indulgence or extension in any form whatsoever;

                           (g) the voluntary or involuntary liquidation,
                  dissolution, sale of all or substantially all of the assets,
                  marshalling of assets and liabilities, receivership,
                  conservatorship, insolvency, bankruptcy, assignment for the
                  benefit of creditors, reorganization, arrangements,
                  composition or readjustment of, or other similar proceeding
                  affecting Landlord, any Tenant or Guarantor or any of their
                  assets or any impairment, modification, release or limitation
                  of liability of Landlord, any Tenant or Guarantor or its
                  estate in bankruptcy or of any remedy for the enforcement of
                  such liability resulting from the operation of any present or
                  future provision of the Federal Bankruptcy Act or other
                  similar statute or from the decision of any court;

                           (h) a Change in Control (as defined in Exhibit "A"
                  attached hereto), upon which the survivor will be deemed to
                  have assumed Guarantor's obligations hereunder;

                           (i) the release of any Tenant from the performance
                  or observance of any of the agreements, covenants, terms or
                  conditions contained in any Lease or this Guaranty by
                  operation of law;

                           (j) the power or authority or lack thereof of
                  Landlord or any Tenant to execute, acknowledge or deliver the
                  Lease to which it is a party;

                           (k) the legality, illegality, validity or invalidity
                  of any Lease;

                           (l) any defenses whatsoever that any Tenant may or
                  might have to the payment of the Monetary


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<PAGE>   5

                  Obligations or to the performance of the Performance
                  Obligations;

                           (m) the existence or non-existence of any Tenant as a
                  legal entity or the cessation of any Tenant being a subsidiary
                  of Guarantor (provided, however, if (i) any Tenant shall
                  assign its Lease to an entity with a rating on its publicly
                  traded unsecured senior debt of "Baa" or better from Moody's
                  Investors Services, Inc. or with a comparable rating by
                  Standard & Poor's Corporation, in accordance with the
                  provisions of Paragraph 17 of such Lease, (ii) such assignee
                  shall expressly assume all obligations of such Tenant under
                  the Lease arising on or after the date of such assignment, by
                  written instrument of assumption delivered to Landlord at the
                  time of such assignment with a duplicate original to Lender
                  which instrument incorporates no collateral matters and which
                  does not alter the obligations under the Lease and (iii) such
                  Tenant has fulfilled all its obligations to Landlord under the
                  Lease which arose prior to the date of such assignment, then
                  this Guaranty shall terminate as to such Tenant; provided,
                  however, that this Guaranty shall not terminate with respect
                  to any violation of the Environmental Laws which arises prior
                  to the date of such assignment unless such assignee assumes
                  all obligations of such Tenant under the Lease with respect to
                  any violation of the Environmental Laws actual or contingent,
                  which arise prior to the date of such Assignment, and
                  provided, further, that if the assignee described in clause
                  (i) above is also a Tenant Affiliate (as such term is defined
                  in the Lease), this Guaranty shall not terminate as to such
                  Tenant);

                           (n) any assignment by Landlord of this Guaranty
                  and/or any Lease (including an assignment by Landlord to any
                  Lender of all of Landlord's right, title and interest in, to
                  and under such Lease and this Guaranty, as collateral security
                  for a Loan) and any subsequent assignment by any such Lender;

                           (o) any default by Guarantor under this Guaranty or
                  any right of setoff, counterclaim or defense (other than
                  payment in full of the Monetary Obligations and the
                  performance of the Performance Obligations in accordance with
                  the terms of the Leases) that Guarantor may or might have to
                  its respective undertakings, liabilities and obligations
                  hereunder, each and every such defense being hereby waived by
                  Guarantor; or

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<PAGE>   6

                           (p) any other cause, whether similar or dissimilar to
                  any of the foregoing, that might constitute a legal or
                  equitable discharge of Guarantor (whether or not Guarantor
                  shall have knowledge or notice thereof) other than payment in
                  full of the Monetary Obligations and performance of the
                  Performance Obligations.

                  Guarantor hereby consents to any and all acts and omissions
referred to in clauses (a) through (f), (i), (j), (k), (n) and (p) above and
agrees that no other consent or approval by Guarantor shall be required in
connection therewith. Without in any way limiting the generality of the
foregoing, Guarantor specifically agrees that if any Tenant's obligations under
the Lease to which it is a party are modified or amended with the express
written consent of Landlord and as otherwise required by Paragraph 34 of the
Leases, the guaranty of Guarantor contained herein shall extend to such
obligations as so amended or modified.

                  4. Guarantor hereby waives notice, demand, protest, notice of
protest and delay or omission of notice of acceleration.

                  5. As to each Lease, Guarantor agrees that the occurrence of
any event described in clauses (vi) or (vii) of Paragraph 19(a) of such Lease
shall, for the purposes of this Guaranty, automatically constitute an Event of
Default under such Lease notwithstanding any restriction which may be imposed by
law on Landlord's right to formally declare the occurrence of an Event of
Default under such Lease by virtue of the occurrence of any such described
event, and Guarantor further agrees that any payment or performance by the
Tenant under such Lease to which Landlord would be entitled upon the declaration
of an Event of Default under such Lease shall automatically constitute Monetary
Obligations and Performance Obligations, respectively, under this Guaranty upon
the occurrence of any such described event notwithstanding any restriction which
may be imposed by law on Landlord's right to assert such Obligations against
such Tenant by virtue of the occurrence of any such described event. In
addition, Guarantor agrees that, in the event of the rejection or disaffirmance
of such Lease by the Tenant thereunder or such Tenant's trustee in bankruptcy
pursuant to bankruptcy law or any other law affecting creditors' rights,
Guarantor will, if Landlord or Lender so requests, assume all obligations and
liabilities of such Tenant under such Lease, to the same extent as if it had
been originally named instead of such Tenant as a party to such document and
there had been no such rejection or disaffirmance; and Guarantor will confirm
such assumption in writing at the request of Landlord or Lender upon or after
such rejection or disaffirmance. Guarantor, upon such assumption, shall have all
rights of such Tenant under such Lease (to the extent permitted by law).

                  6. (a) Any one or combination of any of the following shall
constitute Events of Default hereunder: (i) the failure by Guarantor to perform
any of its agreements contained herein in accordance with the terms hereof; (ii)
any representation or warranty made by Guarantor in this Guaranty, in any other
written materials provided to Lender or Landlord by Guarantor or any Tenant or
in any other instrument which pertains to this Guaranty proves to be incorrect,
now or hereafter, in any material respect; (iii) the entry of an order for
relief by a court having jurisdiction (A) with respect to Guarantor as a debtor,
bankrupt or insolvent, or (B) approving as properly filed a petition seeking
commencement of a case, reorganization,


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<PAGE>   7
arrangement, adjustment or composition in respect of Guarantor under the
Federal Bankruptcy Code or any other applicable Federal or state law, or (C)
appointing a receiver, liquidator, assignee, trustee, United States Trustee,
sequestrator (or other similar official) of Guarantor or of any substantial part
of its properties, or (D) ordering the winding up or liquidation of its affairs,
and in each case any such decree or order continues unstayed and in effect for a
period of 30 consecutive days; (iv) the institution by Guarantor of proceedings
for the commencement of a case for the entry of an order for relief as a debtor,
bankrupt or insolvent, or the consent by Guarantor to the institution of
bankruptcy or insolvency proceedings against Guarantor; (v) the filing by
Guarantor of a petition or answer or consent or the commencement of a case
seeking reorganization or relief under the Federal Bankruptcy Code or any other
applicable federal or state law, or the consent by Guarantor to the filing of
any such petition or the commencement of a case or to the appointment of a
receiver, liquidator, assignee, trustee, United States Trustee, sequestrator (or
other similar official) of Guarantor or of any substantial part of its property,
or the making by Guarantor of an assignment for the benefit of creditors, or the
failure or the admission by Guarantor in writing of its inability to pay its
debts generally as they become due, or the taking of corporate action by it in
furtherance of any such action; (vi) a default under any outstanding
indebtedness of the Guarantor or any of its Subsidiaries or under any mortgage,
indenture or other instrument under which there may be issued or by which there
may be secured or evidenced any indebtedness of the Guarantor or any of its
Subsidiaries or under any guarantee of payment by the Guarantor or any of its
Subsidiaries of indebtedness whether such indebtedness or guarantee now exists
or shall hereafter be created, if the effect of such default is to cause
indebtedness at any one time aggregating in excess of $5,000,000 in principal
amount to become due prior to its stated maturity or failure by the Guarantor or
any of its Subsidiaries to pay at stated maturity any indebtedness of the
Guarantor or any Subsidiary, or under any guarantee of payment by the Guarantor
or any of its Subsidiaries of indebtedness whether such indebtedness or
guarantee now exists or shall hereafter be created at any one time aggregating
in excess of $5,000,000; or final judgments not covered by insurance for the
payment of money which in the aggregate at any one time exceeds $10,000,000
(treating any deductibles, self insurance or retention as not so covered) shall
be rendered against the Guarantor or any of its Subsidiaries by a court of
competent jurisdiction and shall remain undischarged for a period (during which
execution shall not be effectively stayed) of 60 days after such judgment become
final and nonappealable; or (vii) the occurrence of a Change in Control Credit
Event. Upon the occurrence of any such Event of Default, Landlord shall have
whatever rights at law or equity it might have to enforce this Guaranty.

                  (b) Notwithstanding the foregoing, no Event of Default shall
exist under Section 6(a)(vii) hereof by virtue of a Change in Control Credit
Event (as defined in Exhibit "A" attached hereto) unless Guarantor shall fail to
cause each Tenant to make an offer to purchase the Leased Premises as
hereinafter set forth or, in the event such offer is made and accepted by
Landlord, unless and until such Tenant fails to thereafter purchase the Leased
Premises within the time prescribed for such purchase and otherwise in
accordance with the provisions of Paragraphs 16, 27 and 32 of the Lease to which
such Tenant is a party. If a Change in Control Credit Event occurs, then
Guarantor shall cause each Tenant to make, within five (5) days after the
attainment of a conclusive Fair Market Value of the Leased Premises (as defined
in such Tenant's Lease) as determined in accordance with Paragraph 27 of the
Lease, an irrevocable offer of such Tenant to purchase the Leased Premises on
the first Basic Rent Payment Date occurring at least thirty (30) days after
Landlord's acceptance of such offer (the "Covenant Purchase Date") for the
purchase

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<PAGE>   8

price (the "Covenant Offer Amount") specified in the next sentence. The
Covenant Offer Amount shall be the amount as determined in accordance with
Paragraph 27 of such Lease.

                No rejection of an offer hereunder shall be effective for any
purpose unless consented to by Lender. If Landlord shall reject such offer by
notice to Tenant, containing the written consent of Lender to such rejection,
not later than the thirtieth (30th) day following receipt of such offer by
Landlord, then the breach of the covenant under Section 6(a)(vii) hereof shall
be deemed waived by Landlord and the waiver shall remain in effect in the
balance of the term of the Guaranty with respect to the transaction which gave
rise to such breach.

                  Unless Landlord shall have rejected such offer by the
 foregoing notice to each Tenant not later than the thirtieth (30th) day
 following receipt of such Tenant's offer by Landlord, Landlord shall be
 conclusively presumed to have accepted such offer. If such offer is accepted by
 Landlord, each Tenant shall pay to Landlord the Covenant Offer Amount on the
 Covenant Purchase Date and, provided that no Rent or any other charge is due
 and unpaid under the Lease as of the Covenant Purchase Date, Landlord shall
 convey to each Tenant the Leased Premises (as defined in the Lease to which
 such Tenant is a party) in accordance with the provisions of Paragraph 16 of
 such Lease.

                 7. Guarantor hereby agrees that, so long as this Guaranty
shall remain in effect, Guarantor shall furnish to Landlord:

                    (a) as soon as available, but in any event within 120 days
                 after the end of each fiscal year of Guarantor, a copy of (i)
                 the consolidated balance sheet of Guarantor and its
                 consolidated Subsidiaries as at the end of such year and,
                 commencing with the fiscal year ending September 30, 2000, the
                 related consolidated statements of income and retained
                 earnings and changes in financial position for such year,
                 setting forth, commencing with the fiscal year ending
                 September 30, 2000, in each case in comparative form the
                 figures for the previous year, reported on, in all cases,
                 without a "going concern" or like qualification or exception,
                 or qualification arising out of the scope of the audit, by
                 independent certified public accountants of nationally
                 recognized standing, and (ii) the consolidating balance sheet
                 of Guarantor and its consolidated Subsidiaries as at the end
                 of such fiscal year, showing inter-company eliminations, and
                 the related consolidating statements of income and retained
                 earnings and changes in financial position of Guarantor and
                 its consolidated Subsidiaries for such year, showing
                 inter-company eliminations, setting forth, commencing with the
                 fiscal year ending September 30, 2000 in comparative form the
                 figures for the previous year, certified by the Responsible
                 Officer as being fairly stated in all material respects when
                 considered in relation to the consolidated financial


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<PAGE>   9

                 statements of Guarantor and its consolidated Subsidiaries
                 taken as a whole; and

                    (b) as soon as available, but in any event not later than
                 45 days after the end of each of the first three quarterly
                 periods of each fiscal year, commencing with the fiscal year
                 ending September 30, 2000, of Guarantor, the unaudited
                 consolidated balance sheet of Guarantor and its consolidated
                 Subsidiaries as at the end of each such quarter and the
                 related unaudited consolidated statements of income and
                 retained earnings and changes in financial position of
                 Guarantor and its consolidated Subsidiaries for such quarter
                 and the portion of the fiscal year through such date, setting
                 forth, commencing with the fiscal year ending September 30,
                 2000, in each case in comparative form the figures for the
                 corresponding period of the previous year, certified, in all
                 cases, by the Responsible Officer; and

                    (c) as soon as available, but in any event not later than
                 45 days after the end of each calendar month (other than the
                 third, sixth, ninth and twelfth months of each fiscal year of
                 Guarantor), the unaudited consolidated balance sheet of
                 Guarantor and its consolidated Subsidiaries as at the end of
                 each such month and the related unaudited consolidated and
                 consolidating financial statements of Guarantor and its
                 Subsidiaries as at the end of such month in form and detail
                 similar to those customarily prepared by management of
                 Guarantor for internal use, setting forth in each case in
                 comparative form the figures for the corresponding period of
                 the previous year, commencing with the fiscal year ending
                 September 30, 2000, certified by the Responsible Officer; and

                    (d) concurrently with the delivery of the financial
                 statements referred to in subsections 7(b) and 7(c), a balance
                 sheet and statement of earnings of each Tenant, in each case
                 as of the date of, and for the period to which, such
                 accompanying financial statements relate, together with a
                 summary description of the adjustments made to produce such
                 accompanying financial statements out of the balance sheets
                 and statement of earnings of each Tenant;

all such financial statements to be complete and correct in all material
respects (subject, in the case of interim statements, to normal year-end audit
adjustments) and to be prepared in reasonable detail and in accordance with
generally accepted accounting principles ("GAAP") (provided that interim
statements may be condensed and may exclude detailed footnote


                                      -9-
<PAGE>   10

disclosures) applied consistently throughout the periods reflected therein
(except as concurred in by such accountants or officer, as the case may be, and
disclosed therein and except that interim financial statements need not be
restated for changes in accounting principles which require retroactive
application, and operations which have been discontinued (as defined in APB
Opinion No. 30) during the current year need not be shown in interim financial
statements as such either for the current period or the comparable prior
period).

                  As used herein the term "Subsidiaries" shall mean, with
 respect to Guarantor, each corporation or other entity of which a majority of
 the Capital Stock (as such term is defined in Exhibit "A" attached hereto) or
 other ownership interests having ordinary voting power to elect a majority of
 the board of directors or other persons performing similar functions are at the
 time directly or indirectly owned by Guarantor. As used herein the term
 "Responsible Officer" shall mean the chief financial offer of Guarantor.

                 8. Guarantor hereby represents and warrants that: (a) Guarantor
is a corporation duly organized and validly existing under the laws of the State
of Delaware and is duly qualified and in good standing as a foreign corporation
in each of the foreign jurisdictions in which non-qualification would have a
material adverse effect on Guarantor's business or operations; (b) Guarantor has
the requisite power to execute this Guaranty and to perform the provisions
hereof and the execution and delivery of this Guaranty has been duly and validly
authorized by Guarantor; (c) neither the execution and delivery of this Guaranty
nor the consummation of any transaction referred to herein or contemplated
hereby nor the fulfillment of the terms hereof or of any agreement or instrument
referred to in this Guaranty, has constituted or resulted in or will constitute
or result in a breach of the provisions of any material contract to which
Guarantor is a party or by which it is bound, or the violation of any law,
judgment, decree or governmental order, rule or regulation applicable to
Guarantor or any Affiliate (as defined in Exhibit "A" attached hereto) of
Guarantor, or result in the creation under any agreement or instrument of any
security interest, lien, charge or encumbrance upon any of the assets of
Guarantor; (d) all information, reports, papers and data given to Landlord by
Guarantor with respect to Guarantor are accurate in all material respects and
complete insofar as completeness may be necessary to give Landlord accurate
knowledge of the subject matter, and there has been no material and adverse
change in any condition or fact stated therein; (e) there is no action,
proceeding or investigation, pending or, to the best of Guarantor's knowledge,
threatened, or any term of the Guarantor's charter or by-laws or of any
agreement, instrument, judgment, decree, order, statute or governmental rule or
regulation applicable to Guarantor which does or might materially and adversely
affect Guarantor's present or proposed business, assets, operations or
condition, financial or otherwise, or affect (i) Guarantor's entering into this
Guaranty or (ii) the validity and enforceability of this Guaranty; (f) no
consent, approval or authorization of, or declaration or filing with, any
governmental body is required in connection with the execution, delivery,
validity and enforceability of this Guaranty; (g) Guarantor is not in default in
the performance of any material obligation in any instrument to which it is a
party or under which it is obligated; (h) to the best of Guarantor's knowledge,
the representations and warranties of the Tenants in the Leases are true and,
correct; and (i) there has been no material adverse change in the financial
condition of Guarantor since September 30, 2000.

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<PAGE>   11

                  Guarantor further agrees that any claim or claims or liens or
 security interests it may now have or may in the future have against any Tenant
 is subordinate to such Tenant's obligations to Landlord under its respective
 Lease.

                 9. In the event that Guarantor shall perform any Performance
Obligation or pay any Monetary Obligation under a Lease, any right of
subrogation it may have shall be suspended and shall not be effective until all
of the Monetary and Performance Obligations under such Lease shall be fully
discharged to Landlord's and Lender's satisfaction.

                 10. In the event that Landlord or Lender incurs any expenses in
the enforcement of this Guaranty, including reasonable attorneys' fees
reasonably incurred by Lender and Landlord (provided, however, that the
interests of Lender and Landlord shall be represented by one law firm except in
the case of an established conflict of interest), whether or not legal action be
instituted, Guarantor shall pay the same immediately upon demand by Landlord or
Lender, as the case may be.

                 11. Landlord shall not by any act of omission or commission be
deemed to waive any of its rights or remedies hereunder unless such waiver be in
writing and signed by Landlord, and then only to the extent specifically set
forth therein; a waiver on one event shall not be construed as continuing or as
a bar to or waiver of such right or remedy on a subsequent event.

                 12. All notices, demands, requests, consents, approvals,
offers, statements and other instruments or communications required or permitted
to be given pursuant to the provisions of this Guaranty shall be in writing and
shall be deemed to have been given for all purposes when delivered in person or
by Federal Express or other 24-hour delivery service or person or by Federal
Express or other 24-hour delivery service five (5) business days after being
deposited in the United States mail, by registered or certified mail, return
receipt requested, postage prepaid, addressed to the other party at its address
stated above. A copy of any notice given by Guarantor to Landlord shall
simultaneously be given by Guarantor to ReedSmith LLP, 2500 One Liberty Place,
Philadelphia, PA 19103, Attention: Chairman, Real Estate Department. For the
purposes of this Section 12, any party may substitute its address by giving
fifteen (15) days' notice to the other party, in the manner provided above.

                 13. Notice of acceptance of this Guaranty by Landlord or any
Lender or assignee of either of them and notice of any obligations or
liabilities contracted or incurred by any Tenant under its respective Lease are
hereby waived by Guarantor.

                 14. This Guaranty shall be governed by and construed in
accordance with the laws of the State of New York.

                 15. This Guaranty may not be modified or amended except by a
written agreement duly executed by Guarantor with the consent in writing of
Landlord and Lender. This Guaranty shall be binding upon Guarantor and shall
inure to the benefit of Landlord and its assigns as permitted hereunder. In the
event any one or more of the provisions contained in this Guaranty shall for any
reason be held to be invalid, illegal or unenforceable in any respect, such
invalidity, illegality or unenforceability shall not affect any other provision
of this Guaranty, but


                                      -11-
<PAGE>   12

this Guaranty shall be construed as if such invalid, illegal or unenforceable
provision had never been contained herein.

                 16. Capitalized terms not otherwise defined in this Guaranty
shall have the meanings set forth for such terms in the applicable Lease.

                 17. As an additional inducement to Landlord for the execution
and delivery of the Lease Amendments, Guarantor shall pay or cause to be paid to
Landlord simultaneously with the execution and delivery of this Agreement and
the Lease Amendments, a one-time rent payment (in addition to any rent payments
due under the Leases,) in the amount equal to Four Hundred Thousand Dollars
($400,000), payable by wire transfer. In addition, Guarantor shall pay the
reasonable legal fees and expenses of Landlord's counsel in connection with the
execution of this Guaranty and any related transactions thereto.

                 IN WITNESS WHEREOF, Guarantor has caused this Guaranty to be
executed and its corporate seal to be hereunto affixed and attested by its
officers thereunto duly authorized.

                                        SYBRON INTERNATIONAL CORPORATION


                                        By: /s/ DENNIS BROWN
                                            ----------------------------------
                                            Name:  Dennis Brown
                                            Title: VP -- Finance, CPO & Treas.


                                        Attest: /s/ R. JEFFREY HARRIS
                                                --------------------------------
                                                      Secretary

[CORPORATE SEAL]


                                  -12-


<PAGE>   13

                                    EXHIBIT A

                                   DEFINITIONS

                 Certain Terms Defined. The following terms (except as otherwise
expressly provided or unless the context otherwise clearly requires) for all
purposes of this Exhibit A and of any amendment hereto shall have the respective
meanings specified herein. The words "herein" "hereof" and "hereunder" and other
words of similar import refer to this Exhibit A as a whole and not to any
particular Section or other subdivision. The terms defined in this Section
include the plural as well as the singular.

                 "Affiliate" of any Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such Person. For the purposes of this definition, "control" when
used with respect to, any Person means the power to direct the management and
policies of such Person, directly or indirectly, whether through the ownership
of voting securities, by contract or otherwise; and the terms "controlling" and
"controlled" have meanings correlative to the foregoing.

                 "Capital Stock" means, with respect to any Person, any and all
shares, interests, participations, or other equivalents (however designated) of
such Person's capital stock whether now outstanding or issued after the date of
this Guaranty.

                 "Change in Control" means, with respect to the, Guarantor (i) a
sale of all or substantially all of the Guarantor's assets to any Person or
related group of Persons (other than an Affiliate or Affiliates of the
Guarantor) as an entirety or substantially as an entirety in one transaction or
series of transactions, (ii) the merger or consolidation of the Guarantor with
or into another corporation or the merger of another corporation into the
Guarantor with the effect that the Controlling Stockholders hold less than 50%
of the total voting power entitled to vote in the election of directors,
managers or trustees of the surviving corporation of such merger or
consolidation (any nonvoting Common Stock of the surviving corporation having
terms substantially similar to the Guarantor's nonvoting Common Stock shall be
considered voting stock for purposes of this provision) or (iii) the liquidation
or dissolution of the Guarantor.

                 "Change in Control Credit Event" means, with respect to the
Guarantor, a Change in Control immediately after which Guarantor fails to have
either (i) an issue credit rating of "BBB" or better by Standard & Poor's Rating
Corporation or (ii) a publicly traded unsecured senior debt of "Baa" or better
by Moody's Investors Services, Inc..

                 "Common Stock" means, with respect to any Person, any and all
shares, interests, participations and other equivalents (however, designated,
whether voting or non-voting) of such Person's common stock, whether now
outstanding or issued after the date of this Guaranty, and includes, with
limitation, all series and classes of such common stock.

                 "Guarantee" by any Person means any obligation, contingent or
otherwise, of such Person directly or indirectly guaranteeing any debt or other
obligation of any other Person and, without limiting the generality of the
foregoing, any obligation, direct or indirect, contingent or

                                      -13-
<PAGE>   14

otherwise, of such Person (i) to purchase or pay (or advance or supply funds for
the purchase or payment of) such debt or other obligation (whether arising by
virtue of partnership arrangements, by agreement to keep-well, to purchase
assets, goods, securities or services, to take-or-pay, or to maintain financial
statement conditions or otherwise) or (ii) entered into for the purpose of
assuring in any other manner the obligee of such debt or other obligation of the
payment thereof or to protect such obligee against loss in respect thereof
(in whole or in part), provided that the term Guarantee shall not include
endorsements for collection or deposit in the ordinary course of business. The
term "Guarantee" used as a verb has a corresponding meaning.

                 "Person" means an individual, a corporation, a partnership, an
association, a trust or any other entity or organization, including a government
or political subdivision or an agency or instrumentality thereof.

                  "Subsidiary" means, with respect to any Person, any
corporation or other entity of which a majority of the Capital Stock or other
ownership interests having ordinary voting power to elect a majority of the
board of directors or other persons performing similar functions are at the time
directly or indirectly owned by such Person.


                                      -14-