Secure hidden NIR dual image technology obtained on stained cotton materials

For more than ten years ago CMYKIR separation and dual image were performed on standard printing substrate with standard system inks. Principles that were accepted connoted that first image is human visible and second image is hidden, and only instrumentally visualized. In that way perception area is enlarged, while secondary image is hidden and secured. These assumptions opened a wide range of implementation in various reproduction fields, substrates, inks, and gave a wide opportunity o technologists and designers to implement dual image and hidden image technology to unlimited fields of usage. Dual image is performed on cotton fabric, in basic production colored in green, brown and blue color. For colored materials spectrograms and twin pairs are defined. Prints of dual and hidden images performed as infrared technology on cotton are presented.