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Security Marking for Counterfeit Protection

IP.com Disclosure Number: IPCOM000039198D
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 1 page(s) / 13K

Publishing Venue

IBM

Related People

Campbell, AS: AUTHOR [+2]

Abstract

A resistive ribbon printer prints a unique graphical pattern on a label which can be read and verified at a later time by using the printer's printhead to read the pattern by sensing the presence or absence of the conductive ink while scanning the pattern. Since each unique graphical pattern is generated by the operation of an algorithm on a different random seed number and can be verified by decoding the seed number from the graphical pattern, a seller of counterfeit goods could not have a large set of valid graphical patterns for his labels without knowledge of the algorithm used. A seed number is converted into a graphical pattern for printing on a label by a resistive ribbon printer.

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Security Marking for Counterfeit Protection

A resistive ribbon printer prints a unique graphical pattern on a label which can be read and verified at a later time by using the printer's printhead to read the pattern by sensing the presence or absence of the conductive ink while scanning the pattern. Since each unique graphical pattern is generated by the operation of an algorithm on a different random seed number and can be verified by decoding the seed number from the graphical pattern, a seller of counterfeit goods could not have a large set of valid graphical patterns for his labels without knowledge of the algorithm used. A seed number is converted into a graphical pattern for printing on a label by a resistive ribbon printer. The graphical pattern comprises 8 rows by 10 columns of blocks with each block being black or white, whereby the graphical pattern is capable of representing approximately 1.2 x 1024 unique numbers for use in representing the randomly selected seed numbers. The seed number is also included in the graphical pattern in a readable code such as a standard bar code. Verification of the validity of the graphical pattern on the label could be done by reading the pattern during a scan with a thermal printhead having adjacent electrodes in a column functioning as a driver and a sensor and using the algorithm to decode the seed number from its 8-row-by-10-column coded form. This number would then be compared with the number read from the readable code portion of the graphical pattern. The graphical pattern also could be read by optical means rather than by the electrodes of the resistive ribbon printer. Furthermore, because of the unique characteristics of the print produced by the resistive ribbon printer, casual verification may be obtained by viewing the printed patt...