Counterfeiting pharmaceutical packaging has become a major challenge due to the increase of new technologies. Nowadays this issue has spread worldwide and it has become a major threat to the society and economy. The counterfeited pharmaceutical products are unauthorized, stolen, expired, reused and/or manipulated packages which are similar to the original. The main problem is that it is difficult to see visual differences between original and fake packaging, and the lack of solutions to identify the authentic packaging. So packaging authentication is a very important need in pharmaceutical industry.The simplest way to produce fake samples of printed packaging is to scan the image of the original package by different devices, such as digital camera, mobile camera, scanner etc., next to print the scanned image by printers. The printer’s color gamut corresponds to the volume of the color solid defined colorimetrically, produced by a particular set of inks and substrate, which contains all the colors that the printer can produce. Since most of the pharmaceutical products are packed in aluminum foils, gravure printing is used as printing technology. In this study, blister foils have been used as printing substrate to identify an original print printed on it, using different gravure printing machines. In this preliminary study, an image of a reference color chart (IT8.7/3) was printed with three different 4-color gravure printing machines. The volume of the color gamut of a printed sample (original) and a scanned reprinted sample (fake) have been studied to identify the difference between them. Experimental results show that when a scanned sample is reprinted with different printers, the gamut volume differences are much higher than when the original artwork if printed with different gravure printers.

Color gamut CMYK reflectance spectrum Gravure printing