| http://www.w3.org/ns/prov#value | - A met hod for reading of invisible marking, which comprises applying infrared rays of 2-10 ??m wavelength onto an invisible marking-printed material obtained by the method of any of claims 1-15, to measure the infrared absorptivities of the invisible marking area and other area of said material and identify the information signified by the invisible marking.
|
