Infrared-absorbing mark printed matter

摘要

Infrared-absorbing mark printed matter has an infrared-absorbing mark formed on a substrate by printing with an ink having high light absorptivity in the infrared region; the infrared-absorbing mark is covered up by smearing with an ink having high light absorptivity in the visible region and pervious to light in the infrared region to form a coloured concealing layer; on the coloured concealing layer is formed a white concealing layer by printing with an ink containing a white pigment and an extender pigment of which at least part of the particles are those having an average particle size of 3 to 20 mu m. In this printed matter, the infrared-absorbing mark is perfectly concealed so that it is invisible to the naked eye, and the image of the printed matter is improved.