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                                  EXHIBIT 3(b)

                              MINNTECH CORPORATION
                                 RESTATED BYLAWS
                            AS OF SEPTEMBER 14, 1995



                                   ARTICLE I.
                           CORPORATE OFFICES AND SEAL

     Section 1.01.  OFFICES.  The  corporation may have offices within the State
of Minnesota or at such other places as the Board of Directors may from time
to time appoint or the business of the corporation may require.

                                   ARTICLE II.
                            MEETINGS OF STOCKHOLDERS

     Section 2.01.  PLACE OF MEETINGS.  Meetings of the stockholders may be held
at any place, within or without the State of Minnesota, as designated by the
President or the Board of Directors in the notice of meeting, and in the absence
of such designation, shall be held at the office of the corporation in the State
of Minnesota.
     Section 2.02.  REGULAR MEETINGS.  Regular meetings of the stockholders of
this corporation may be held at the discretion of the Board of Directors on an
annual or less frequent periodic basis on such date and at such time and place
as may be designated by the President or the Board of Directors in the notice of
meeting.  At regular meetings, the stockholders shall elect Directors and
transact only such other business as is properly brought before the meeting in
accordance with these Bylaws.  If a regular meeting of stockholders has not been
held for a period of fifteen (15) months, one or more stockholders holding not
less than three percent (3%) of all voting stock of the corporation may call a
regular meeting of stockholders by delivering to the President or Treasurer a
written demand for a regular meeting. Within thirty (30) days after receipt of
such written demand by the President and Treasurer, the Board of Directors shall
cause a regular meeting of stockholders to be called and held on notice no
later than  ninety (90) days after the receipt of written demand, all at the
expense of the corporation.


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     Section 2.03.  SPECIAL MEETINGS.  Special meetings of the stockholders may
be called by the President, the Chief Financial Officer, or by the Board of
Directors or any two or more members thereof only for the purpose of transacting
such business as is properly brought before the meeting in accordance with these
Bylaws.  Special meetings may also be called by one or more stockholders holding
not less than ten percent (10%) of the voting power of all shares of the
corporation entitled to vote (except that a special meeting called for the
purpose of considering any action to directly or indirectly facilitate or effect
a business combination, including any action to change or otherwise affect the
composition of the Board for that purpose, must be called by stockholders
holding not less than twenty-five percent (25%) of the voting power of all
shares of the corporation entitled to vote), who shall demand such special
meeting by written notice given to the President or the Chief Financial Officer
of the corporation specifying the purposes of such meeting.  Within thirty (30)
days after the receipt of such a written demand for a special meeting of
stockholders by the President or the Chief Financial Officer, the Board of
Directors shall cause a special meeting of stockholders to be called and held on
notice no later than ninety (90) days after the receipt of such written demand.
Business transacted at any special meeting of the stockholders shall be limited
to the purpose or purposes stated in the notice of meeting.
     Section 2.04.  NOTICE OF MEETINGS.  Except where a meeting of stockholders
is an adjourned meeting and the dates, time, and place of such meeting were
announced at the time of adjournment, notice of all meetings of stockholders
stating the date, time, and place thereof, and any other information required by
law or desired by the Board of Directors or by any other person or persons
calling the meeting, and in the case of a special meeting, the purpose thereof,
shall be given to each stockholder of record entitled to vote at such meeting
not less than seven (7) nor more than sixty (60) days prior to the date of such
meeting.  In the event that a plan of merger, exchange, sale or other
disposition of all or substantially all of the assets of the corporation is to
be considered at a meeting of stockholders, notice of such meeting  shall be
given to every stockholder, whether or not entitled to vote, not less than
fourteen (14) days prior to the date of such meeting.



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     Section 2.05.  Quorum; Adjourned Meetings.  The holders of a majority of
the stock issued and outstanding and entitled to vote there at, present in
person or represented by proxy, shall constitute a quorum, and the presence of
such majority stockholders shall be required at all meetings of the stockholders
for the transaction of business, except as otherwise provided by law, by the
Articles of Incorporation, or by these Bylaws.  If, however, such majority shall
not be present or represented at any meeting of stockholders, the stockholders
entitled to vote there at, present in person or represented by proxy, shall have
the power to adjourn the meeting from time to time, without notice other than
announcement at the meeting, until the requisite amount  of voting stock shall
be present.  At any such adjourned meeting at which the requisite amount of
voting stock shall be represented, any business may be transacted which might
have been transacted at the meeting as originally called.
     Section 2.06.  VOTING AND PROXIES.  At each meeting of the stockholders,
every stockholder having the right to vote shall be entitled to vote in person
or by proxy appointed by an instrument in writing subscribed by such stockholder
and conforming to the requirements established by law.  Each stockholder shall
have one vote for each share of stock having voting power registered in his
name on the books of the corporation.  All questions regarding the qualification
of voters, the validity of appointments of proxies, and the acceptance or
rejection of votes shall be decided by the presiding officer of the meeting.
The vote of the holders of the  voting power of a majority of the shares having
voting power  present in person or represented by proxy shall decide any
question brought before any duly held meeting, except as to any  question upon
which any different vote is required by law, the Articles of Incorporation, or
these Bylaws.
     Section 2.07.  To be properly brought before a regular or special meeting
of stockholders, business must be of a nature that is appropriate for
consideration at a meeting of share holders and must be (i) specified in the
notice of the meeting (or any supplement thereto) given by or at the direction
of the Board of Directors, (ii)otherwise properly brought before the meeting by
or at the direction of the Board of Directors, or (iii) otherwise properly
brought before the meeting by a shareholder.  In addition to any other
applicable requirements for business to be properly brought


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before a meeting of shareholders by a shareholder, the shareholder must have
given timely notice thereof in writing to the Secretary of the corporation.  To
be timely, each such notice  must be given, either by personal delivery or by
United States Mail, postage prepaid, to the Secretary of the corporation, not
less than fifty (50) days nor more than seventy-five (75) days prior to the
meeting; provided, however, that in the event that less than sixty (60) days'
notice or prior public disclosure of the date of the meeting is given or made to
shareholders, notice by the shareholder to be timely must be so received not
later than the close of business on the 10th day following the day on which such
notice of the date of the meeting was mailed or such public disclosure was made,
whichever first occurs.  Each such notice to the Secretary shall set forth as to
each matter the shareholder proposes to bring before the meeting (w) a brief
description of the business desired to be brought before the meeting and the
reasons for conducting such business at the meeting, (x) the name and address of
record of the shareholder proposing such business, (y) the class or series (if
any) and the number of shares of the corporation which are  owned by the
shareholder, and (z) any material interest of the shareholder in such business.
Notwithstanding anything in these Bylaws to the contrary, no business shall be
transacted at the meeting except in accordance with the procedures set forth in
this Article; provided, however, that nothing in this Article shall be deemed to
preclude discussion by any shareholder of any business  properly brought before
the meeting, in accordance with these Bylaws.


                                  ARTICLE III.
                                    DIRECTORS

     Section 3.01.  POWERS.  The  property, affairs  and  business of the
corporation shall be managed by the Board of Directors.  In  addition to the
powers and authorities by these Bylaws expressly  conferred upon it, the Board
may exercise all such powers of the corporation and do all such lawful acts and
things as are not by statute or by the Articles of Incorporation or by these
Bylaws directed or required to be exercised or done by the stockholders.
     Section 3.02.  QUALIFICATIONS; TERM OF OFFICE.  Directors need not be
stockholders.  A director shall hold office until the annual meeting for the
year in which his term expires and until


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his successor shall be elected and shall qualify, subject however to prior
death, resignation, retirement or removal for cause. stockholders may remove a
director from office only for cause.
     Section  3.03.  NOTICE OF NOMINATIONS OF THE DIRECTORS. Nominations for the
election of directors may be made by the Board of Directors or by any
stockholder entitled to vote for the election of directors.  Notice of
nominations which are proposed by the Board of Directors shall be given by the
President or the Chairman of the Board of Directors on behalf of the Board of
Directors.  However, any shareholder entitled to vote generally in the election
of directors may nominate one or more persons for election as directors at a
meeting only if written notice of such shareholder's intent to make such
nomination or nominations has been given, either by personal delivery or by
United States mail, postage prepaid, to the secretary of the corporation not
less than  fifty (50) days nor more than seventy-five (75) days prior to the
meeting; provided,  however, that in the event that less than sixty (60) days'
notice or prior public disclosure of the date of the meeting is given or made to
shareholders, notice by the shareholder to be timely must be so received not
later than the close of business on the 10th day following the day on which such
notice of the date of meeting was mailed or such public disclosure was made,
whichever first occurs.  Each such notice to the secretary shall set forth: (i)
the name and address of record of the shareholder who intends to make the
nomination; (ii) a representation that the shareholder is a holder of record of
shares of the corporation entitled to vote at such meeting and intends to appear
in person or by proxy at the meeting to nominate the person or persons specified
in the notice;  (iii) the name, age, business and residence addresses, and
principal occupation or employment of each nominee; (iv) a description of all
arrangements or understandings between the shareholder and each nominee and any
other person or persons (naming such person or persons) pursuant to which the
nomination or nominations are to be made by the shareholder; (v) such  other
information regarding each nominee proposed by such shareholder as would be
required to be included in a proxy statement filed pursuant to the proxy rules
of the Securities and Exchange Commission; and (vi) the consent of each nominee
to serve as a director of the corporation if so elected.


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The corporation may require any proposed nominee to furnish such other
information as may reasonably be required by the corporation to determine the
eligibility of such proposed nominee to serve as a director of the corporation.
The presiding officer of the meeting may, if the facts warrant, determine that a
nomination was not made in accordance with the foregoing procedure, and if he
should so determine, he shall so declare to the meeting and the defective
nomination shall be disregarded.
     Section 3.04.  VACANCIES; NEWLY CREATED DIRECTORSHIPS.  Any vacancy
occurring in the Board of Directors may be filled for the unexpired term by the
affirmative vote of a majority of the directors remaining in office, even though
said remaining directors be less than a quorum.  Any newly created directorship
resulting from an increase in the authorized number of directors by action of
the Board of Directors may be filled, for a term determined by the Board of
Directors consistent with the Articles of Incorporation, by a majority vote of
the directors serving at the time of such increase.
     Section 3.05.  MEETINGS.  Meetings of the Board of Directors shall be held
immediately after, and at the same place as, regular meetings of stockholders.
Other meetings of the Board of Directors may be held at such times and places as
shall from time to time be determined by the Board of Directors.  Meetings of
the Board of Directors also may be called by any director, in which case the
person or persons calling such meeting may fix the date, time, and place
thereof, and shall cause notice of meeting to be given.
     Section 3.06.  NOTICE OF MEETINGS.  If the date, time, and place of the
meeting of the Board of Directors has been announced at the previous meeting, no
notice is required.  In all other cases, twenty-four (24) hours' notice of
meetings of the Board of Directors, stating the date and time thereof and any
other information required by law or desired by the person or persons calling
such a meeting, shall be given to each director.  If notice of meeting is
required, and such notice does not state the place of the meeting, such meeting
shall be held at the principal executive office of the corporation.  Notice of
meetings of the Board of Directors shall be given to directors in the manner
provided in Article VI of these Bylaws for the giving of notice.


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     Section 3.07.  MEETINGS BY ELECTRONIC COMMUNICATION.  Members of the Board
of Directors or any committee designated by the Board of Directors, may
participate in a meeting of the Board of Directors or of any such committee by
means of conference telephone or similar communication equipment by means of
which all persons participating in the meeting can simultaneously hear each
other, and participation in such a manner shall constitute presence in person at
such meeting.
     Section 3.08.  QUORUM AND VOTING.  A majority of the directors currently
holding office shall constitute a quorum for the transaction of business at any
meeting of the Board of Directors.  In the absence of a quorum, a majority of
the directors present may adjourn the meeting from time to time until a quorum
is present.  The Board of Directors shall take action by the affirmative vote of
the majority of the directors present at any duly held meeting, except as to any
question upon which any different vote is required by law, the Articles of
Incorporation, or these Bylaws.
     Section 3.09.  COMMITTEES.  The Board of Directors, by resolution approved
by the affirmative vote of the majority of the directors then holding office,
may establish one or more committees of one or more persons having the authority
of the Board of Directors in the management of the business of the corporation
to the extent provided in such resolution.  Such committees, however, shall at
all times be subject to the direction and control of the Board of Directors.
Committee  members need not be directors and shall be appointed by the
affirmative vote of a majority of the directors present.  The majority of the
members of any such committee shall constitute a quorum for the transaction of
business at a meeting of any such committee.  In other matters of procedure, the
provisions of these Bylaws shall apply to the committees and the members thereof
to the same extent they apply to the Board of Directors and directors,
including, without limitation, the provisions with respect to meetings and
notice thereof, absent members, written actions, electronic communications, and
valid acts.  Each committee shall keep regular minutes of its proceedings and
report the same to the Board of Directors.
     Section 3.10.  ACTION IN WRITING.  Any action required or permitted to be
taken by a meeting of the Board of Directors, or lawfully constituted committee
thereof, may be taken by written


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action signed by all of the Directors then in office or by all of the members of
a committee established by the Board of Directors, as the case may be.


                                   ARTICLE IV.
                                    OFFICERS

     Section 4.01.  NUMBER.  The officers of the corporation shall be chosen by
the directors, and shall consist of a Chairman of the Board (if one is elected
by the Board), a President, one or more Vice Presidents, a Secretary, a
Treasurer and such Assistant Secretaries and Assistant Treasurers and such other
officers and agents as the Board of Directors from time to time shall elect or
appoint.  Any two offices may be held by the same person.
     Section 4.02.  TERM OF OFFICE; REMOVAL; AND VACANCIES.  Any officer shall
hold office until his successor shall have been duly elected, unless prior
thereto he shall have resigned or been removed from office as hereinafter
provided.  Any officer or agent elected or appointed by the Board of Directors
shall hold office at the pleasure of the Board of Directors and may be removed,
with or without cause, at any time by the vote of a majority of the Board of
Directors.  Any vacancy in an office of the corporation shall be filled by the
Board of Directors.
     Section 4.03.  CHAIRMAN OF THE BOARD.  The Chairman of the Board, if one is
elected, shall preside at all meetings of the stockholders and directors and
shall have such other duties as may be prescribed from time to time, by the
Board of Directors.
     Section 4.04.  PRESIDENT.  The President shall be the chief executive
officer of the corporation.  In the absence of the Chairman of the Board, he
shall preside at all meetings of stockholders and directors; he shall be
responsible for general and active management of the business of the
corporation; and he shall see that all orders and resolutions of the Board are
carried into effect.  He shall have the general powers and duties usually vested
in the office of the President and chief executive officer and shall have such
other powers and perform such other duties as the Board of Directors may from
time to time prescribe.


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     Section 4.05.  VICE PRESIDENT.  The Vice President, if any, or Vice
Presidents in case there be more than one, shall have such powers and perform
such duties as the president or the Board of Directors may from time to time
prescribe.
     Section 4.06.  SECRETARY.  The  Secretary shall attend all meetings of the
Board of Directors and of the stockholders and shall maintain records of, and
whenever necessary, certify all proceedings of the Board of Directors and of the
stockholders.  He shall keep the stock books of the corporation, and when so
directed by the Board of Directors, shall give or cause to be given notice of
meetings of the stockholders and meetings of the Board of Directors.  He shall
also perform such other duties and have such other powers as the President or
the Board of Directors may from time to time prescribe.
     Section 4.07.  TREASURER.  The Treasurer shall be the chief financial
officer of the corporation.  He shall have the care and custody of the corporate
funds and securities of the corporation and shall disburse the funds of the
corporation as may be ordered from time to time by the President or the Board of
Directors.  He shall keep full and accurate financial records for the
corporation  and shall have such other powers and perform such other duties as
the President or the Board of Directors may from time to time prescribe.
     Section 4.08.  OTHER  OFFICERS.  The Assistant Secretaries and Assistant
Treasurers in the order of their seniority, unless otherwise determined by the
Board of Directors, shall, in the absence or disability of the Secretary or
Treasurer, perform the duties and exercise the powers of the Secretary and
Treasurer respectively.  Such Assistant Secretaries and Assistant Treasurers
shall have such other powers and perform such other duties as the President or
the Board of Directors may from time to time prescribe.  Any other officer
appointed by the Board of Directors shall hold office at the pleasure of the
Board of Directors.  He shall have such powers, perform such duties, and be
responsible to such other officers as the Board of Directors may from time to
time prescribe.
     Section 4.09.  DELEGATION OF DUTIES.  In case of the absence of any officer
of the corporation, or for any other reason that the Board may deem sufficient,
the Board may delegate


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for the time being the powers and duties, or any of them of such officer to any
other officer or to any director or directors.


                                   ARTICLE V.
                              CERTIFICATES OF STOCK

     Section 5.01.  CERTIFICATES.  Certificates of stock of the corporation
shall be numbered and shall be entered into the books of the corporation as they
are issued.  Each such certificate shall exhibit the holder's name and number of
shares, and shall contain any other information required by law or desired by
the Board of Directors and shall be signed by the President or any Vice
President and the Treasurer or the Assistant Treasurer, or the Secretary or
Assistant Secretary.
     Section 5.02.  LOSS OF CERTIFICATES.  Any person claiming a certificate of
stock to be lost or destroyed shall make an affidavit in such manner as the
Board of Directors may require and shall, if the Directors so require, give the
corporation a bond of indemnity in form and amount and with one or more sureties
satisfactory to the Board, whereupon a new certificate may be issued of the same
tenor and for the same number of shares as the one alleged to be lost or
destroyed.

                                   ARTICLE VI.
                                    NOTICES

     Section 6.01.  GENERAL.  Whenever notice is required to be given to any
stockholder or director, such notice may be given by either oral or written
communication.  A written notice shall be delivered by hand or mailed to the
stockholder or director for whom it is intended at such address as appears on
the books of the corporation or shall be given by any other method which
conforms to law.  Notice by mail shall be deemed given when deposited in the
United States mail with sufficient postage affixed.
     Section 6.02.  WAIVER OF NOTICE.  Whenever any notice is required to be
given to any stockholder, director or officer under the provisions of these
Bylaws, the Articles of Incorporation or by statute, such notice may be waived
in the manner provided by law.


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                                  ARTICLE VII.
                                 INDEMNIFICATION

     Section 7.01.  The corporation shall indemnify its officers, directors,
employees and agents to the full extent permitted by the laws of the State of
Minnesota, as now in effect, or as the same may be hereafter amended.

                                  ARTICLE VIII.
                                   AMENDMENTS

     Section 8.01.  These Bylaws may be amended or altered by the Board of
Directors at any meeting provided that notice of any such proposed amendment
shall have been given in the notice given to the directors of such meeting.
Such authority in the Board of Directors is subject to the power of the
stockholders to change or repeal such Bylaws.