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Method and apparatus for authenticating documents utilizing poled polymeric material

  • US 4,792,667 A
  • Filed: 03/27/1987
  • Issued: 12/20/1988
  • Est. Priority Date: 03/27/1987
  • Status: Expired due to Fees
First Claim
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1. A method for authenticating documents utilizing the ferroelectric properties exhibited by polymeric materials, comprising the steps of:

  • (a) affixing a poled polymeric material to a first surface of a document substrate, thereby forming a document sandwich with obverse and reverse sides;

    (b) physically stimulating said polymeric material;

    (c) detecting a level of current flow between said obverse and reverse sides of said document sandwich, said level of current flow and its polarity is indicative of the polarized sate of the polymeric material;

    (d) electrically comparing said current flow to a fixed reference;

    (e) activating an indicating device if said current flow substantially equals said fixed reference.

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