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                                                                   EXHIBIT 99.1

                          REGISTRATION RIGHTS AGREEMENT

     This REGISTRATION RIGHTS AGREEMENT (the "Agreement") is entered into as of
this 9th day of April, 1998, by and among SYBRON INTERNATIONAL CORPORATION (the
"Company") and the AFFILIATES of LRS Acquisition Corp. ("LRS") who are
identified on the signature page to this Agreement (each an "Affiliate" for
purposes hereof and, collectively, the "Affiliates").

     WHEREAS, pursuant to that certain Agreement and Plan of Reorganization
entered into by and among the Company, Normandy Acquisition Co., a wholly owned
subsidiary of the Company, LRS and Liberty Partners Holdings 5, L.L.C.
("Liberty") dated as of January 23, 1998 (the "Merger Agreement"), each share of
the issued and outstanding capital stock of LRS, an outstanding warrant held by
Liberty to purchase LRS capital stock and certain outstanding options for such
capital stock were converted into or exchanged for common stock of the Company,
par value $0.01 per share ("Common Stock"), registered on Form S-4 (the "S-4
Registration Statement") under the Securities Act of 1933, as amended (the
"Act"), resulting in the issuance of an aggregate of 3,215,982 shares of Common
Stock (the "Merger Shares"); and

     WHEREAS, pursuant to the Merger Agreement, each Affiliate received the
number of Merger Shares that is set forth opposite such Affiliate's name on the
signature page to this Agreement (collectively, the "Shares"); and

     WHEREAS, the Merger Shares have been registered on the S-4 Registration
Statement for issuance pursuant to the Merger Agreement in accordance with Rule
145 ("Rule 145") promulgated by the Securities and Exchange Commission (the
"Commission") under the Act, with the result that the Shares are eligible for
resale by the Affiliates without registration under the Act in compliance with
the conditions set forth in Rule 145(d); and

     WHEREAS, the Company has provided certain demand registration rights to the
Affiliates with respect to the Shares, as described in the Merger Agreement,
this Agreement and the Affiliate Letter delivered by each Affiliate pursuant to
the Merger Agreement, to provide additional liquidity during the period that the
conditions of Rule 145(d) continue to apply to the Shares; and

     WHEREAS, concurrently with the execution of this Agreement the Affiliates
are exercising their demand registration rights and the Company has agreed to
register the Shares for resale as described in this Agreement (the "Demand
Registration").

     NOW, THEREFORE, in consideration of the Recitals and of the mutual
covenants, conditions and agreements set forth herein and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, it is hereby agreed as follows:


                                    ARTICLE I

                                   DEFINITIONS

     In addition to the terms defined above, when used in this Agreement the
following terms shall have the meanings specified:

     1.1  "Exchange Act" shall have the meaning set forth in Section 2.3(a).

     1.2  "Law" shall mean any federal, state, local or other law, rule,
regulation or governmental requirement or restriction of any kind, including any
rules, regulations or orders promulgated thereunder and any final orders,
decrees, policies, consents or judgments of any regulatory agencies, courts or
other Persons.



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     1.3  "Person" shall mean a natural person, corporation, trust, partnership,
limited liability company, association, governmental entity, agency or branch or
department thereof, or any other legal entity.

     1.4  "Registration Expenses" shall have the meaning set forth in Section
2.5(a).

     1.5  "Registration Shares" shall have the meanings set forth in Section
2.1(a).

     1.6  "Registration Statement" shall mean, as the case may be, either a
post-effective amendment on Form S-3 to the S-4 Registration Statement or a
separate Form S-3 registration statement, each as described in Section
2.1(a)(i).

     1.7  "Registration Term" shall have the meaning set forth in Section 
2.3(f).


                                   ARTICLE II

                               REGISTRATION RIGHTS

     2.1   Demand Registration Rights.

           (a)   Effecting the Registration. Promptly following execution of
this Agreement, the Company shall use reasonable efforts to effect the Demand
Registration with respect to all of the Shares (the "Registration Shares"),
provided that:

           (i)    the Company shall be required to effect the Demand    
     Registration  only if the Company is able to file a post-effective
     amendment on Form S-3 to the S-4 Registration Statement to include a
     reoffer prospectus covering resale of the Registration Shares or,
     alternatively, if Form S-3 under the Act (or any comparable short-form
     registration then in effect) is then available for use by the Company;

           (ii)   the Demand Registration shall not be required to become
     effective at any time prior to the date the Company issues a public        
     earnings release reporting earnings that include at least 30 days worth of
     results from the operations of the LRS business; and

           (iii)  the Company's obligation to effect the Demand Registration
     pursuant to the provisions of this Agreement shall be deemed to have been
     satisfied if after the filing of the Registration Statement, the failure of
     such Registration Statement to become effective is due solely to the
     actions or inactions of the Affiliates or if, once effective, the
     effectiveness of the Registration Statement is withdrawn solely because of
     an Affiliate's actions or inactions.

     (b)    Manner of Sale. The Registration Statement shall provide that the
Registration Shares will be sold by the Affiliates only through routine 
brokerage transactions, to dealers or in negotiated transactions.

     (c)    No Piggyback Registration. The Registration Statement shall 
not register any shares of Common Stock on behalf of any shareholders of the 
Company other than the Affiliates.

     2.2   Indemnity.

           (a)   Company Indemnification. The Company will indemnify and
hold harmless each Affiliate and, if applicable, each director and officer of
such Affiliate (and any Person who controls such Affiliate within the meaning of
Section 15 of the Act) against all claims, losses, damages, liabilities, actions
and expenses resulting from any untrue statement or alleged untrue statement of
a material fact contained in the prospectus or in the related Registration
Statement, or in any notification or the like, and from any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading, except insofar as the same may have been
based on information furnished in


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writing to the Company by such Affiliate expressly for use therein and used in
accordance with such writing. The Company agrees to reimburse each indemnified
Person for any legal or other expenses reasonably incurred in con nection with
investigating or defending any such loss, claim, damage, liability, action or
expense.

           (b)    Affiliate Indemnification. Each Affiliate, by acceptance of
the registration provisions provided herein, agrees to indemnify and hold       
harmless the Company, its officers and directors (and any Person who controls
the Company within the meaning of Section 15 of the Act) against all claims,
losses, damages, liabilities, actions and expenses resulting from any untrue
statement or alleged untrue statement of a material fact furnished in writing
to the Company by that Affiliate expressly for use in connection with the
registration or qualification effected pursuant to this Agreement and used in
accordance with such writing and from any omission therefrom or alleged
omission therefrom of a material fact needed to be furnished in order to make
the information that was furnished, in light of the circumstances, not
misleading. Each Affiliate also agrees to reimburse each indemnified Person for
any legal or other expenses reasonably incurred in connection with
investigating or defending any such loss, claim, damage, liability, action or
expense. Notwithstanding anything in the foregoing to the contrary, the
aggregate amount for which each Affiliate may be liable pursuant to this
Section 2.2(b) and Section 2.2(c) shall not exceed the net proceeds to such
Affiliate resulting from the sale of such Affiliate's Registration Shares
pursuant to the Registration Statement.

           (c)    Contribution. In order to provide for just and equitable
contribution in circumstances under which the indemnification provided for in
Sections 2.2(a) and 2.2(b) is applicable but for any reason is held to be
unenforceable, the indemnifying party shall contribute to the aggregate claims,
losses, damages, liabilities, actions and expenses of the nature contemplated
by such indemnity incurred by the indemnified party or parties in such
proportion as is just and equitable, taking into account the relative fault of
the parties, provided that no Person guilty of fraudulent misrepresentation
(within the meaning of Section 11(f) of the Act) shall be entitled to
contribution from any Person who is not guilty of such fraudulent
misrepresentation.

           (d)   Notice. Any Person entitled to indemnification hereunder will
(i) give prompt written notice to the indemnifying party of any claim with
respect to which indemnification is sought and (ii) unless a conflict of
interest exists between such indemnified and indemnifying parties with respect
to such claim, permit such indemnifying party to assume the defense of such
claim with counsel reasonably satisfactory to the indemnified party. If
such defense is assumed, the indemnifying party will not be subject to
liability for any additional legal fees of the indemnified party or for any
settlement made by the indemnified party without the indemnifying party's
consent. An indemnifying party which is not entitled to, or elects not to,
assume the defense of a claim will not be obligated to pay the fees and
expenses of more than one counsel for all parties indemnified by such
indemnifying party with respect to such claim.

     2.3   Registration Covenants of the Company. The Company covenants
and agrees that the Company will use reasonable efforts to effect the Demand
Registration and cooperate in the sale of the Registration Shares to be
registered and, until expiration of the Registration Term, to:

           (a)    promptly prepare and file the Registration Statement (as
well as any necessary amendments or supplements thereto) with the Commission and
use reasonable efforts to cause such Registration Statement to become effective
in accordance with Section 2.1(a)(ii);

           (b)    furnish to the Affiliates sufficient copies of the
Registration Statement and any amendments or supplements thereto and any
prospectus forming a part thereof, which documents will be subject to the review
of counsel for the Affiliates prior to the filing thereof;

           (c)    notify the Affiliates, promptly after the Company shall
receive notice thereof, of the time when the Registration Statement becomes
effective or when any amendment or supplement to any prospectus forming a part
of the Registration Statement has been filed;

           (d)    notify the Affiliates promptly of any request by the
Commission for the amending or supplementing of the Registration Statement or
prospectus or for additional information;



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           (e)    advise the Affiliates after the Company shall receive notice
or obtain knowledge thereof of the issuance of any order by the  Commission
suspending the effectiveness of the Registration Statement or amendment thereto
or of the initiation or threatening of any proceeding for that  purpose, and
promptly use reasonable efforts to prevent the issuance of any stop order or to
obtain its withdrawal promptly if such stop order should be issued;

           (f)    prepare and file with the Commission such amendments and
supplements to the Registration Statement and the prospectus forming a part
thereof as may be necessary to keep the Registration Statement effective until
either the first anniversary of the execution of this Agreement or, if
applicable, such shorter period of time which shall terminate (i) when all
Shares covered by the Registration Statement have been sold, or (ii) on the date
the resale restrictions applicable to the Shares pursuant to Rule 145(d) expire
or are rescinded (the "Registration Term");

           (g)    furnish to the Affiliates such number of copies of the
Registration Statement, each amendment and supplement thereto, the prospectus
included in the Registration Statement (including each preliminary prospectus)
and such other documents as the Affiliates may reasonably request in order to
facilitate the disposition of the Registration Shares owned by the Affiliates;

           (h)    assist the Affiliates in satisfying their prospectus
delivery obligations by furnishing to any national securities exchange on which
the Registration Shares are then listed copies of the prospectus and each
amendment or supplement thereto in accordance with Rule 153 under the Act (or
any comparable rule then in existence);

           (i)    use reasonable efforts to register or qualify the
Registration Shares under such securities or blue sky Laws of such
jurisdictions as are mutually determined by the Company and the Affiliates and
do any and all other acts and things which may be reasonably necessary or
advisable to enable the Affiliates to consummate the disposition in such
jurisdictions of the Registration Shares; provided that nothing herein shall
require the Company to  (i) qualify generally to do business in any
jurisdiction where it would not otherwise be required to qualify but for this
subsection, (ii) subject itself to taxation in any such jurisdiction or (iii)
consent to general service of process in any such jurisdiction;

           (j)    notify the Affiliates, at any time when a prospectus relating
thereto is required to be delivered under the Act, of the happening of any
event as a result of which the Registration Statement contains an untrue 
statement of a material fact or omits to state any material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they were made, not misleading, and, at the request of
an Affiliate, amend or supplement the Registration Statement so that the
Registration Statement will not contain an untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading. The Affiliates acknowledge that any notice given by the
Company hereunder may constitute material nonpublic information and that
applicable securities Laws prohibit a Person who has material nonpublic
information about a company from purchasing or selling securities of such
company or from communicating such information to any other Person under
circumstances where it is reasonably foreseeable that such Person is likely to
purchase or sell such securities;

           (k)   cause all Registration Shares to continue to be listed on each
securities exchange on which similar securities issued by the Company are then
listed; 

           (l)   ensure the continued availability of a transfer agent and
registrar for all Registration Shares;

           (m)   make available for inspection by each Affiliate and any
attorney, accountant or other agent retained by such Affiliate, subject to the
Company's receipt of acceptable confidentiality agreements from the recipients
thereof, such financial and other records, pertinent corporate documents and
other properties and personnel of the Company as may be reasonably requested in
connection with the Registration Statement; and

           (n)   use its best efforts to timely file with the Commission 
all of the reports it is required to file under the Exchange Act as a
prerequisite to availability of Form S-3.



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     2.4   Registration Covenants of the Affiliates. In consideration of
the benefits accruing to them pursuant to this Agreement and in addition to
their other obligations set forth in this Agreement, each Affiliate covenants
and agrees to:

           (a)   cooperate with the Company, its counsel, advisors and 
other representatives, and comply with all applicable provisions of Law
(including without limitation the prospectus delivery requirements of the Act
and Rule 10b-5 and Regulation M under the Securities Exchange Act of 1934, as
amended) in connection with any registration effected pursuant to the provisions
of this Agreement;

           (b)   promptly provide to the Company, in writing, such information
as the Company or its counsel deems necessary or appropriate for inclusion in
the Registration Statement, which information, when given, shall be true and
correct in all material respects and shall not omit any information necessary
to make the information furnished not misleading; 

           (c)   refrain from transferring, by any means, ownership of or any
other interest in the Shares prior to the earnings release date identified in
Section 2.1(a)(ii) above; 

           (d)   execute all questionnaires, powers of attorney or other
documents as the Company may reasonably request;

           (e)   discontinue sales of Registration Shares upon notification of
any stop order or suspension of the effectiveness of the Registration Statement;

           (f)   notify the Company immediately upon any material change in the
plan of distribution or other information concerning such Person described in
the prospectus; 

           (g)   discontinue sales of Registration Shares and use of the
related prospectus following notification by the Company that the Registration
Statement must be amended or supplemented;

           (h)   not use any prospectus other than the most recent prospectus
related to the Registration Statement; and 

           (i)   upon presentation of a stock certificate representing
Registration Shares sold under the Registration Statement, certify that the sale
was made in accordance with the terms hereof and the plan of distribution
described in the Registration Statement.

In the event that any Affiliate fails to comply in any material respect with its
obligations pursuant to Sections 2.4(a) through (d), any Shares held by such
Affiliate may be excluded from the Registration Statement and all of such
Affiliate's rights pursuant to this Agreement shall terminate. In the event that
any Affiliate fails to comply in any material respect with its obligations
pursuant to Sections 2.4(e) through (i), all of such Affiliate's rights pursuant
to this Agreement shall terminate other than with respect to Registration Shares
then registered on a Registration Statement.

     2.5   Expenses.

           (a)   General. All expenses incident to the Company's performance of
or compliance with this Agreement, including, without limitation,  all
registration and filing fees, fees and expenses of compliance with securities
or blue sky Laws, printing expenses, messenger and delivery expenses, and fees  
and disbursements of counsel for the Company and all independent certified
public accountants and other Persons retained by the Company (all such expenses
being herein called "Registration Expenses"), will be borne by the Company. In
addition, the Company will pay its internal expenses (including, without
limitation, all salaries and expenses of its officers and employees performing
legal or accounting duties).

           (b)    Affiliates' Counsel. The Company will reimburse the
Affiliates for the reasonable fees and disbursements of one counsel mutually
chosen by the Affiliates in connection with the Demand Registration.


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           (c)    Other. To the extent Registration Expenses are not required
to be paid by the Company, each Affiliate will pay those Registration  Expenses
which are allocable to the registration of such Affiliate's securities included
in the Registration Statement, and any Registration Expenses not so     
allocable will be borne by all of the Affiliates in proportion to the aggregate
selling price of the securities to be registered.

     2.6   S-3 Qualification. The Company hereby represents and warrants to the
Affiliates that, as of the date of this Agreement, it has reasonable grounds to
believe that it meets all of the requirements for filing a registration
statement on Form S-3. 


                                   ARTICLE III

                                  MISCELLANEOUS

     3.1   Survival. All agreements, representations and warranties made
in this Agreement or in any document delivered pursuant to this Agreement shall
survive the execution of this Agreement, the delivery of any such document and
the sale of Shares pursuant to the Registration Statement.

     3.2   Governing Law. This Agreement and the other documents issued
pursuant to this Agreement shall be governed by the Laws of the State of
Wisconsin.

     3.3   Counterparts; Headings. This Agreement may be executed in several
counterparts, each of which shall be deemed an original, but such  counterparts
shall together constitute but one and the same agreement. The   Article and
Section headings in this Agreement are inserted for convenience of reference
only and shall not constitute a part hereof.

     3.4   Entire Agreement. This Agreement, the Affiliate Letters
delivered pursuant to the Merger Agreement and the other documents referred to
herein and therein contain the entire understanding of the parties with respect
to the subject matter hereof. There are no restrictions, promises, warranties,
covenants or undertakings concerning such subject matter other than those
expressly set forth in this Agreement and such Affiliate Letters. This Agreement
and the Affiliate Letters supersede all prior negotiations, agreements and
undertakings between the parties with respect to such subject matter.

     3.5    Notices. All communications or notices required or permitted by
this Agreement shall be in writing and shall be deemed to have been  given at
the earlier of the date when actually delivered to a Person by personal 
delivery, commercial courier or telephonic facsimile transmission accompanied
by a telephonic facsimile receipt and followed by hard copy by United States
mail, or three (3) days after being deposited in the United States mail,
certified or registered mail, postage prepaid, return receipt requested, and
addressed as follows, unless and until any of such parties notifies the others
in accordance with this Section of a change of address:

           If to the Company:       Sybron International Corporation
                                    Attention: R. Jeffrey Harris, Esq.
                                    411 East Wisconsin Avenue
                                    Suite 2400
                                    Milwaukee WI  53202
                                    Fax No. 414/390-5476



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     with a copy to
     (which copy shall
     not be deemed
     notice to the
     Company):                  Quarles & Brady
                                Attention: Kathryn M. Coates, Esq.
                                411 East Wisconsin Avenue
                                Milwaukee, WI 53202
                                Fax No. 414/271-3552
     
     If to an Affiliate:        To the address of such Affiliate set forth
                                for such Affiliate on the signature page to
                                this Agreement.
     
     3.6   Amendments; Successors and Assigns. This Agreement may be 
amended if such amendment is in writing and is signed by the Company and
Affiliates who own at least two-thirds (2/3s) of the Shares then owned by all
Affiliates. This Agreement may be assigned by an Affiliate only with the prior
written consent of the Company (which consent shall not be unreasonably
withheld). This Agreement will be binding upon, inure to the benefit of and be
enforceable by the parties hereto and their respective successors and permitted
assigns.

     3.7   Severability. Any provision of this Agreement which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction,  be
ineffective to the extent of such prohibition or unenforceability without       
invalidating the remaining provisions of this Agreement or affecting the
validity or enforceability of such provision in any other jurisdiction.

     3.8   Interpretation. Unless the context requires otherwise, all words
used in this Agreement in the singular number shall extend to and include 
the plural, all words in the plural number shall extend to and include the
singular, and all words indicating a gender shall extend to and include all
genders. In addition, any reference to a "Section" herein shall be a reference
to such Section of this Agreement unless otherwise indicated.

                                      * * *



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             IN WITNESS WHEREOF, the parties hereto have executed this
Registration Rights Agreement as of the day and year first above written.

                               SYBRON INTERNATIONAL CORPORATION
      
      
                               By: /s/R. Jeffrey Harris
                                   ---------------------------------------    
                                   R. Jeffrey Harris, Vice President -
                                   General Counsel and Secretary
      


AFFILIATES:                                           No. of Shares Received
                                                      Pursuant to the
                                                      Merger Agreement:
                                                      ----------------
                                                
/s/William Crouse                                       100,630
- ----------------------------------------                -------
William Crouse                                  
                                                
         c/o HealthCare Ventures                
         44 Nassau Street                       
         Princeton, New Jersey  08542           
         Fax No.:             
                 -----------------                               
                                                
/s/Gordie Nye                                            84,003
- ----------------------------------------                 ------
Gordie Nye                                      
                                                
         7908 Lowry Terrace                     
         La Jolla, California  92037            
         Fax No.:(619) 459-4563                 
                 --------------                               
                                                
/s/Kenneth Rainin                                     1,114,309
- ----------------------------------------              ---------
Kenneth Rainin                                  
                                                
         c/o Rainin Instrument Co.              
         5400 Hollis Street                     
         Emeryville, California  94608          
         Fax No.:(510) 652-5865                 
                 --------------                               
                                                
/s/Robert B. Stockman                                   294,013
- ----------------------------------------                -------
Robert B. Stockman                              
                                                
         c/o Johnston Associates, Inc.          
         181 Cherry Valley Road                 
         Princeton, New Jersey  08540           
         Fax No.:(609) 683-7524                 
                 --------------                               


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/s/Andrew J. Futey                                      25,510
- ----------------------------------------                ------
Andrew J. Futey

         11416 Caminito Corriente
         San Diego, California  92128
         Fax No.:(619) 635-7666
                 --------------

/s/Charles Madsen                                       15,854
- ----------------------------------------                ------
Charles Madsen

         1535 Laburnum Road
         Hoffman Estates, Illinois  60195
         Fax No.:(847) 358-7428
                 --------------

/s/David J. Milner                                      14,622
- ----------------------------------------                ------
David J. Milner

         17207 North Woodson Court
         Ramona, California  92065
         Fax No.:(619) 635-7668
                 --------------

/s/Michael P. Oliver                                     9,748
- ----------------------------------------                 -----
Michael P. Oliver

         12433 Rue Fountainbleau
         San Diego, California  92131
         Fax No.:
                 -----------------

/s/Richard Poinsett                                      4,874
- ----------------------------------------                 -----
Richard Poinsett

         11067 Ipai Court
         San Diego, California  92127
         Fax No.:
                 -----------------

LIBERTY PARTNERS HOLDINGS 5, L.L.C.

By: /s/Michael J. Kluger                             1,075,719
    ------------------------------------             ---------
    Name:  Michael J. Kluger
           -----------------------------
    Title: Managing Director
           -----------------------------

         1177 Avenue of the Americas
         New York, New York  10036
         Attn: Michael J. Kluger
         Fax No.:(212) 354-0336
                 --------------



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STATE BOARD OF ADMINISTRATION OF FLORIDA

By: /s/Michael J. Kluger                                151,965
    ------------------------------------                -------
    Name:  Michael J. Kluger
           -----------------------------
    Title: Managing Director
           -----------------------------

         c/o Liberty Capital Partners, Inc.
         1177 Avenue of the Americas
         New York, New York  10036
         Attn: Michael J. Kluger
         Fax No.:(212) 354-0336
                 --------------


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