On 1 July, 2013 Croatia becomes the 28th star on the European flag.
To commemorate the accession of Croatia to the European Union, Croatian Post issued a special souvenir sheet on 1st July 2013,using innovative Infrared printing technic.
The souvenir sheet of face value 20.00 HRK has a motif of Croatia on the map of Europe. The stamp was designed by Jana Žiljak Vujić, renowned designeress from Zagreb. She and her team for the first time “incorporated“ a renowned scientific invention named INFRAREDESIGN (IRD), i.e. a design of two mutually dependent images on one surface.
At the leading international exhibition of innovations and new products – INPEX, held in Pittsburgh, Jana Žiljak Vujić and her team have been awarded gold medal and special recognition for the best European innovation for this invention.
This is the first postage stamp in the EU on which double content printed on the same surface using this new technology. One image is visible by naked eye in real conditions while the other is visible in close infrared area i.e. through infrared glasses or infrared camera.
In this Croatian sheet, in the background, under infrared light, first two strophes of the national anthem of the Republic of Croatia are visible.