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                                                                     EXHIBIT 3.1

                          CERTIFICATE OF INCORPORATION

                                       OF

                          DAY INTERNATIONAL GROUP, INC.

         FIRST: The name of the corporation (hereinafter referred to as the
"Corporation") is Day International Group, Inc.

         SECOND: The address of its registered office in the State of Delaware
is 9 East Loockerman Street, Suite 1B, Dover, DE 19901. The name of its
registered agent at such address is National Registered Agents, Inc.

         THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware.

         FOURTH:

A.       AUTHORIZED SHARES

The total number of shares of capital stock which the Corporation has authority
to issue is 855,000 shares consisting of:

         (1)      500,000 shares of a class of Cumulative Preference Stock, par
         value $.01 per share (the "Cumulative Preference Stock"); and

         (2)      105,000 shares of Preferred Stock, par value $.01 per share
         (the "Preferred Stock"); and

         (3)      200,000 shares of Class A Voting Common Stock, par value $.01
         per share (the "Class A Common Stock"); and

         (4)      50,000 shares of Class B Non-Voting Common Stock, par value
         $.01 per share (the "Class B Common Stock" and, together with the Class
         A Common Stock, the "Common Stock").

The number of authorized shares of the class of Cumulative Preference Stock may
be increased or decreased, but not below the number of shares thereof
outstanding, by the affirmative vote of the holders of a majority of the stock
of the Corporation entitled to vote irrespective of subsection (b)(2) of Section
242 of the General Corporation Law of State of Delaware.

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         a.       Common Stock

                  1.       The rights, preferences, privileges and restrictions
                  of the Class A Common Stock and the Class B Common Stock shall
                  be equal and identical in all respects except as provided in
                  Section a.3 below and except to the extent otherwise required
                  by law, the holders of shares of the Class A Common Stock
                  shall have the exclusive voting rights and power of the Common
                  Stock, and the holders of shares of the Class B Common Stock
                  shall not be entitled to vote upon the election of directors
                  or upon any other matters, provided that the holders of shares
                  of the Class B Common Stock shall be entitled to notice of,
                  and to attend, stockholders' meetings.

                  2.       Subject to all of the rights of the Preferred Stock,
                  dividends may be paid on the Common Stock, as and when
                  declared by the Board of Directors, out of any funds of the
                  Corporation legally available for the payment of such
                  dividends.

                  3.       The holders of the Class B Common Stock shall have
                  the following conversion rights:

                           (i)      Upon the occurrence of any Conversion Event
                           (as defined herein), each holder of Class B Common
                           Stock shall be entitled to convert into the same
                           number of shares of Class A Common Stock any or all
                           of the shares of such holder's Class B Common Stock
                           being sold, distributed or otherwise disposed of or
                           converted in connection with the occurrence of such
                           Conversion Event. For purposes of this Section a. (a)
                           a "Conversion Event" shall mean any transfer of
                           shares of Class B Common Stock to any person or
                           persons who are not affiliates of the transferor,
                           including, without limitation, pursuant to any public
                           offering or public sale of securities of the
                           Corporation (including a public offering registered
                           under the Securities Act of 1933 and a public sale
                           pursuant to Rule 144 under the Securities Act of 1933
                           or any similar rule then in force), (b) a "person"
                           shall mean any natural person or any corporation,
                           partnership, joint venture, trust, unincorporated
                           organization and any other entity or organization and
                           (c) an "affiliate," with respect to any person, shall
                           mean such person's spouse, parents, members of such
                           person's family or such person's lineal descendants
                           and any other person than directly, or indirectly
                           thorough one or more intermediaries, controls, or is
                           controlled by, or is under common control with, such
                           person.

                           (ii)     Subject to clause (i), each conversion of
                           shares of Class B Common Stock into shares of Class A
                           Common Stock at the option of the holder shall be
                           effected by the surrender of the certificate or
                           certificates representing the shares to be converted
                           at the principal office of the Corporation at any
                           time (including within a reasonable time prior to the
                           occurrence of any Conversion Event, if necessary to
                           effect the conversion of shares related thereto,
                           provided, however, that the holders of such

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                           shares will not be entitled to vote on any matters to
                           be voted on by the Corporation's stockholders during
                           such interim period, such certificates being deemed
                           to represent only shares of Class B Common Stock for
                           such purpose) during normal business hours, together
                           with a written notice by the holder of such Class B
                           Common Stock stating that a Conversion Event has
                           occurred or is expected to occur and that such holder
                           desires to convert the shares, or a stated number of
                           the shares, of such Class B Common Stock represented
                           by such certificate or certificates into shares of
                           Class A Common Stock (and including instructions of
                           issuance of the Class A Common Stock to be issued
                           upon such conversion). Each conversion at the option
                           of the holder shall be deemed to have been effected
                           as of the close of business on the later of (a) the
                           date on which the Conversion Event has occurred and
                           (b) the date on which such certificate or
                           certificates have been surrendered and such notice
                           has been received, and at such later time the rights
                           of the holder of the converted Class B Common Stock,
                           as a holder of Class B Common Stock, shall cease and
                           the person or persons in whose name or names the
                           certificate or certificates for shares of Class A
                           Common Stock are to be issued upon such conversion
                           shall be deemed to have become the holder or holders
                           of record of the shares represented thereby. Promptly
                           after the Conversion Event has occurred and the
                           surrender of certificates and the receipt of written
                           notice, the Corporation shall issue and deliver in
                           accordance with the surrendering holder's
                           instructions (x) the certificate or certificates for
                           the shares of Class A Common Stock issuable upon such
                           conversion and (y) a certificate representing any
                           shares of Class B Common Stock which were represented
                           by the certificate or certificates delivered to the
                           Corporation in connection with such conversion but
                           which were not converted. If any shares of Class B
                           Common Stock are converted into shares of Class A
                           Common Stock in connection with a Conversion Event
                           and such shares of Class A Common Stock are not
                           actually sold, distributed or otherwise disposed of
                           so that a Conversion Event does not actually occur,
                           such shares of Class A Common Stock shall be
                           automatically converted back into the same number of
                           shares of Class B Common Stock.

                           (iii)    The issuance of certificates upon conversion
                           will be made without charge to the holders of such
                           shares for any issuance tax in respect thereof or
                           other cost incurred by the Corporation in connection
                           with such conversion, except that the holder of any
                           such shares shall be responsible for the payment of
                           all applicable transfer taxes if the shares of Class
                           A Common Stock are issued in the name of a person or
                           persons other than such holder.

                           (iv)     The Corporation shall at all times reserve
                           and keep available out of its authorized but unissued
                           shares of Class A Common Stock solely for the purpose
                           of issuance upon the conversion of the Class B Common
                           Stock

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                           such number of shares of Class A Common Stock
                           issuable upon the conversion of all outstanding
                           shares of Class B Common Stock. All shares of Class A
                           Common Stock which are so issuable shall, when
                           issued, be duly and validly issued, fully paid and
                           non-assessable and free from all taxes, liens and
                           charges (other than as created by or through the
                           holder thereof). The Corporation shall take all such
                           actions as it deems necessary or appropriate to
                           assure that all such shares of Class A Common Stock
                           may be so issued without violation of any applicable
                           law or governmental regulation or any requirements of
                           any domestic securities exchange upon which shares of
                           Class A Common Stock may be listed.

                           (v)      Except as provided in the last sentence of
                           the first paragraph of clause (ii), shares of Class B
                           Common Stock that are converted into shares of Class
                           A Common Stock as provided herein shall be retired
                           and cancelled and shall not be reissued.

         b.       PREFERRED STOCK

         Shares of Preferred Stock may be issued from time to time in one or
         more series. The Board of Directors of the Corporation is hereby
         authorized to determine and alter all rights, preferences and
         privileges and qualifications, limitations and restrictions thereof
         (including, without limitation, voting rights and the limitation and
         exclusion thereof) granted to or imposed upon any wholly unissued
         series of Preferred Stock and the number of shares constituting any
         such series and the designation thereof, and to increase or decrease
         (but not below the number of shares of such series then outstanding)
         the number of shares of any series subsequent to the issue of shares of
         that series then outstanding. In the event that the number of shares of
         any series is so decreased, the shares constituting such reduction
         shall resume the status which such shares had prior to the adoption of
         the resolution originally fixing the number of shares of such series.

         c.       CUMULATIVE PREFERENCE STOCK

         Shares of Cumulative Preference Stock may be issued from time to time
         in one or more series. Unless consented to by the affirmative vote of
         the holders of a majority of the Preferred Stock, Cumulative Preference
         Stock shall, in respect to dividend distributions and distributions
         upon the liquidation, winding-up and dissolution of the Company, rank
         junior to the Preferred Stock. In all other respects, the Board of
         Directors of the Corporation is hereby authorized to determine and
         alter all rights, preferences and privileges and qualifications,
         limitations and restrictions thereof (including, without limitation,
         voting rights and the limitation and exclusion thereof) granted to or
         imposed upon any wholly unissued series of Cumulative Preference Stock
         and the number of shares constituting any such series and the
         designation thereof, and to increase or decrease (but not below the
         number of shares of such series the outstanding) the number of shares
         of any series subsequent to the issue of shares of that series the
         outstanding. In the event that the number of any shares is so
         decreased, the shares constituting such
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         reduction shall resume the status which such shares had prior to the
         adoption of the resolution originally fixing the number of shares of
         such series.

         FIFTH: The name and mailing address of the incorporator is as follows:

                  NAME           ADDRESS
                  Jill Henderson c/o Kirkland & Ellis
                                 655 Fifteenth Street, N.W.
                                 Suite 1200
                                 Washington, D.C. 20005

         SIXTH: The Corporation is to have perpetual existence.

         SEVENTH: In furtherance and not in limitation of the powers conferred
by statute, the Board of Directors is hereby authorized to adopt, amend or
repeal the bylaws of the Corporation.

         EIGHTH: Meetings of stockholders may be held within or without the
State of Delaware, as the bylaws may provide. The books of the Corporation may
be kept outside the State of Delaware at such place or places as may be
designated from time to time by the Board of Directors or in the bylaws of the
Corporation. Elections of directors need not be by written ballot unless the
bylaws of the Corporation so provide.

         NINTH: Whenever a compromise or arrangement is proposed between the
Corporation and its creditors or any class of them and/or between the
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of the Corporation or any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for the Corporation under the
provisions of Section 191 of Title 8 of the Delaware Code or on the application
of trustees in dissolution or of any receiver or receivers appointed for the
Corporation under the provisions of Section 279 of Title 8 of the Delaware Code,
order a meeting of the creditors or class of creditors, and/or the stockholders
or class of stockholders of the Corporation, as the case may be, to be summoned
in such manner as the said court directs. If a majority in number representing
three-fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of the Corporation, as the case may be,
agree to any compromise or arrangement and to any reorganization of the
Corporation as a consequence of such compromise or arrangement, the said
compromise or arrangement and the said reorganization shall, if sanctioned by
the court to which the said application has been made, be binding on all the
creditors or class of creditors, and/or on all the stockholders, or class of
stockholders, of the Corporation, as the case may be, and also on this
Corporation.

         TENTH: To the fullest extent permitted by the General Corporation Law
of the State of Delaware including, without limitation, Section 102(b)(7)), as
amended from time to time, no director of the Corporation shall be liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director. Any repeal or amendment of this Article TENTH or adoption of
any provision of the Certificate of Incorporation inconsistent with this Article
TENTH shall have prospective effect only and shall not adversely affect the
liability of a

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director of the Corporation with respect to any act or omission occurring at or
before the time of such repeal, amendment or adoption of an inconsistent
provision.

         ELEVENTH: The Corporation shall, to the fullest extent permitted by the
General Corporation Law of the State of Delaware (including, without limitation,
Section 145 thereof), as amended from time to time, indemnify any promoter or
director whom it shall have power to indemnify from and against any and all of
the expenses, liabilities or other losses of any nature. The indemnification
provided in this Article ELEVENTH shall not be deemed exclusive of any other
rights to which those indemnified may be entitled under any bylaw, agreement,
vote of stockholders or disinterested directors or otherwise, both as to action
in his or her official capacity and as to action in another capacity while
holding such office, and shall continue as to a person who has ceased to be
promoter or director and shall inure to the benefit of the heirs, executors and
administrators of such a person.

         TWELFTH: The Corporation elects not to be governed by Section 203 of
the General Corporation Law of the State of Delaware.

         THIRTEENTH: The Corporation reserves the right to amend or repeal any
provision contained in this Certificate of Incorporation in the manner now or
hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.

         I, THE UNDERSIGNED, being the incorporator hereinafter named, for the
purpose of forming a corporation pursuant to the General Corporation Law of the
State of Delaware, do make this Certificate, hereby declaring and certifying
that this is my act and deed and the facts stated herein are true, and
accordingly, have hereunto set my hand on this 5th day of April, 1995.

                                               /s/ Jill Henderson
                                               ---------------------------------
                                               Jill Henderson, Sole Incorporator