EXHIBIT 3.15

STATE OF DELAWARE
SECRETARY OF STATE 55       FROM CORP LEGAL CMI
DIVISION OF CORPORATIONS
FILED 02:30 AM 01/15/1991
721015110 - 2252202

                          CERTIFICATE OF INCORPORATION

                                       OF

                    CINCINNATI MILACRON RESIN ABRASIVES INC.

                       ----------------------------------

                      A corporation organized pursuant to
              the General Corporation Law of the State of Delaware

             ------------------------------------------------------

                                   ARTICLE I

                                      Name

      The name of the corporation (hereinafter called the "Corporation") is:

                    CINCINNATI MILACRON RESIN ABRASIVES INC.

                                   ARTICLE II

                     Registered Office and Registered Agent

      The address of the Corporation's registered office in the State of
Delaware is 1209 Orange Street, in the City of Wilmington, County of New Castle.
The name of the Corporation's registered agent at such address is The
Corporation Trust Company.

                                   ARTICLE III

                Business or Purposes To Be Conducted or Promoted

      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
Delaware.



                                       2

                                   ARTICLE IV

                                 Capital Stock

      The total number of shares of all classes of capital stock which the
Corporation shall have authority to issue is 1,000 shares of Common Stock, par
value $1,00 per share.

                                   ARTICLE V

                                  Incorporator

      The name and mailing address of the incorporator of the Corporation is
Walter S. Wood, 4701 Marburg Avenue, Cincinnati, Ohio 45209.

                                   ARTICLE VI

                    Business and Affairs of the Corporation

      SECTION 1. Elections of directors need not be by written ballot unless and
except to the extent the By-laws of the Corporation (the "By-laws") shall
provide.

      SECTION 2. Any director or any officer of the Corporation elected or
appointed by its stockholders or by its Board of Directors, or any committee
thereof, may be removed at any time by a unanimous consent of the stockholders
or in such other manner as shall be provided in the By-laws, except as otherwise
provided by law.

      SECTION 3. In furtherance and not in limitation of the powers conferred by
the laws of the State of Delaware, the Corporation, in the By-laws, may
authorise and empower the Board of Directors to adopt, amend or repeal the
By-laws in the manner not inconsistent with the laws of the State of Delaware or
this Certificate of Incorporation; the stockholders of the Corporation entitled
to vote, however, retain the power to adopt, amend or repeal the By-laws.



                                       3

                                  ARTICLE VIII

                                Indemnification

      To the fullest extent that the General Corporation Law of the State of
Delaware as its exists on the date hereof or as it may hereafter be amended
permits the limitation or elimination of the liability of directors, 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. No amendment to or
repeal of this Article shall apply to or have any effect on the liability or
alleged liability of any director of the Corporation for or with respect to any
acts or omissions of such director occurring prior to such amendment or repeal.

      I, the undersigned, being the incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the General Corporation Law of
Delaware, do make this certificate, hereby declaring and certifying, under
penalties of perjury, that this is my act and deed and the facts herein stated
are true, and accordingly have hereunto set by hand as of January 15, 1991.

                                                /s/ Walter S. Wood
                                                --------------------------------
                                                Walter S. Wood
                                                Incorporator



                                                          STATE OF DELAWARE
                                                          SECRETARY OF STATE
                                                       DIVISION OF CORPORATIONS
                                                       FILED 10:00 AM 09/24/1998
                                                          981371000 - 2252202

                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION

CINCINNATI MILACRON RESIN ABRASIVES INC., a corporation organized and existing
under and by virtue of the General Corporation Law of the State of Delaware,

DOES HEREBY CERTIFY:

FIRST: That the Board of Directors of said corporation, at a meeting duly held,
adopted a resolution proposing and declaring advisable the following amendment
to the Certificate of Incorporation of said corporation:

      RESOLVED, that the Certificate of Incorporation of CINCINNATI MILACRON
      RESIN ABRASIVES INC. be amended by changing the First Article and Heading
      thereof so that, as amended, said Article and Heading shall be and read as
      follows:

      The name of the company is      Milacron Resin Abrasives Inc.

SECOND: That in lieu of a meeting and vote of shareholders, the stockholders
have given written consent to said amendment in accordance with the provisions
of Section 228 of the General Corporation Law of the State of Delaware.

THIRD: That the aforesaid amendment was duly adopted in accordance with the
applicable provisions of Sections 242 and 228 of the General Corporation Law of
the State of Delaware.

FOURTH: This Certificate of Amendment shall be effective on October 10, 1998.

IN WITNESS WHEREOF, said CINCINNATI MILACRON RESIN ABRASIVES INC. has caused
this certificate to be signed by Wayne F. Taylor, its Secretary and Assistant
Treasurer, this 24 day of September, 1998.

                                        CINCINNATI MILACRON RESIN ABRASIVES INC.

                                        By: /s/ Ronald L. Smith
                                            ------------------------------------
                                            Ronald L. Smith, President