
<PAGE>   1
                                                                     EXHIBIT 5.1


                          [FENNEMORE CRAIG LETTERHEAD]


October 31, 1997


ADFlex Solutions, Inc.
2001 West Chandler Boulevard
Chandler, Arizona  85224

RE:   ADFlex Solutions, Inc. Registration Statement on Form S-8
      for the 1996 Outside Director Option Plan

Ladies and Gentlemen:

      We have acted as special counsel to ADFlex Solutions, Inc., a Delaware
corporation (the "Company"), in connection with the Registration Statement on
Form S-8 (the "Registration Statement"), to be filed by the Company with the
Securities and Exchange Commission (the "Commission"). The Registration
Statement relates to the registration under the Securities Act of 1933, as
amended (the "Act"), of 12,000 shares (the "Shares") of the Company's Common
Stock, par value $.01 per share, to be issued under the Company's 1996 Outside
Director Stock Option Plan (the "Plan").

      In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of (i) the Plan, (ii) the
Restated Certificate of Incorporation and the Bylaws of the Company, (iii)
certain resolutions of the Board of Directors of the Company relating to the
Plan, (iv) the form of Registration Statement proposed to be filed with the
Commission, and such other documents as we have deemed necessary or appropriate
as a basis for the opinions set forth below. In such examination, we have
assumed the genuineness of all 
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FENNEMORE CRAIG

ADFlex Solutions, Inc.
October 31, 1997
Page 2


signatures, the legal capacity of natural persons, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such latter documents. As to any facts material
to this opinion which we did not independently establish or verify, we have
relied upon statements and representations of officers and other representatives
of the Company and others.

      Based upon and subject to the foregoing and the limitations set forth
below, we are of the opinion that the Shares have been duly authorized and,
after the Registration Statement becomes effective and when the Shares are
issued and sold in accordance with the Plan and the Form S-8 prospectus to be
delivered to the Plan participant, for consideration having a value at least
equal to the par value thereof, the Shares will be duly issued, fully paid and
nonassessable.

      We are opining herein as to the effect on the subject transaction only of
United States federal law and the Delaware General Corporation Law, and we
assume no responsibility as to the applicability thereto, or the effect thereon,
of the laws of any other jurisdiction.

      This opinion is furnished to you solely for your benefit in connection
with the filing of the Registration Statement and is not to be used, circulated,
quoted or otherwise referred to for any other purpose without our prior written
consent. Notwithstanding the foregoing, we hereby consent to the filing of this
opinion with the Commission as Exhibit 5.1 to the Registration Statement. In
giving this consent, we do not thereby admit that we are included in the
category of persons whose consent is required under Section 7 of the Act or the
rules and regulations of the Commission.

                                    Very truly yours,

                                /s/ Fennemore Craig, a Professional Corporation

                                    Fennemore Craig, a Professional Corporation


KCM/WTE
