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                                                                    EXHIBIT 3.13

                         CERTIFICATE OF INCORPORATION

                                      OF

                             RADNOR DELAWARE, INC.

       FIRST:     The name of the corporation is RADNOR DELAWARE, INC.

       SECOND:    The registered office of the corporation in the State of
Delaware is located at 1209 Orange Street, Wilmington, Delaware, 19801, County
of New Castle.  The registered agent of the corporation at that address is The
Corporation Trust Company.

       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; provided that the corporation's
activities shall be confined to the maintenance and management of its intangible
investments and the collection and distribution of the income from such
investments or from tangible property physically located outside Delaware, all
as defined in such manner to qualify for exemption from income taxation under,
Section 1902(b)(8) of Title 30 of the Delaware Code, or under the corresponding
provision of any subsequent law.

       FOURTH:    The corporation shall have authority to issue One Thousand
(1,000) shares of common stock, having a par value of $.001 per share.

       FIFTH:     The corporation shall indemnify directors and officers of the
corporation to the fullest extent permitted by law.

       SIXTH:     The directors of the corporation shall incur no personal
liability to the corporation or its stockholders for monetary damages for any
breach of fiduciary duty as a director; provided, however, that the directors of
the corporation shall continue to be subject to liability (i) for any breach of
their duty of loyalty to the corporation or its stockholders, (ii) for acts or
omissions not in good faith or which
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involve intentional misconduct or a knowing violation of law, (iii) under
Section 174 of the General Corporation Law of the State of Delaware, or (iv) for
any transaction from which the directors derived an improper personal benefit.
In discharging the duties of their respective positions, the board of directors,
committees of the board, individual directors and individual officers may, in
considering the best interest of the corporation, consider the effects of any
action upon employees, suppliers and customers of the corporation, communities
in which officers or other establishments of the corporation are located, and
all other pertinent factors. In addition, the personal liability of directors
shall further be limited or eliminated to the fullest extent permitted by any
future amendments to Delaware law.

       SEVENTH:   The business and affairs of the corporation shall be managed
by or under the direction of the board of directors, the number of members of
which shall be set forth in the bylaws of the corporation.  The directors need
not be elected by ballot unless required by the bylaws of the corporation.

       EIGHTH:    Meetings of the stockholders will be held within the State of
Delaware.  The books of the corporation will be kept (subject to the provisions
contained in the General Corporation Law) in 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.

       NINTH:     In the furtherance and not in limitation of the object,
purposes and powers prescribed herein and conferred by the laws of the State of
Delaware, the board of directors is expressly authorized to make, amend and
repeal the bylaws.

       TENTH:     The corporation reserves the right to amend or repeal any
provision contained in this Certificate of Incorporation in the manner now or
hereinafter prescribed by the laws of the State of Delaware.  All rights herein
conferred are granted subject to this reservation.

       ELEVENTH:  The corporation shall have no power and may not be authorized
by its stockholders or directors (i) to perform or omit to do any act that would
prevent, inhibit, or cause the corporation to lose its status as a corporation

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exempt from the Delaware Corporation Income Tax under Section 1902(b)(8) of
Title 30 of the Delaware Code, or under the corresponding provision of any
subsequent law, or (ii) to conduct any activities in any state other than
Delaware which could result in the corporation being subject to the taxing
jurisdiction of any state other than Delaware.

       TWELFTH:   The name and mailing address of the incorporator is Donna
Juhrden, 314 South State Street, Dover, Delaware 19901.

       THIRTEENTH:  The powers of the incorporator shall terminate upon the
election of directors.

       I, THE UNDERSIGNED, being the incorporator, for the purpose of forming a
corporation under the laws of the State of Delaware do make, file and record
this Certificate of Incorporation, and, accordingly, have hereunto set my hand
and seal this 12th day of January, 1998.


                                    /s/ Donna Jurden
                                   -------------------------------------
                                   Donna Juhrden, Sole Incorporator

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