Security document with hidden security feature

A security document (30) comprising a region (20), in which a first print information (21) and a second print information (22) are stored, which produce under predetermined ambient conditions an identical color impression, so that under the given environmental conditions, a homogeneous uniform color impression of the first print information (21) and the second print information (22) is produced in the region (20) and the first print information (21) and the second print information (22) on the basis of the induced color impression can not be distinguished, in which the second print information (22) is formed by an ink which has a structural color, the induced color impression can be varied by a stimulus, wherein the structural color with which the second print information is formed during exposure of the excitation due to an induced change of an internal structure having a perceived color which is different from the color impression of the first print information, characterized, in that the first print information (21) is formed by means of a further structural color, the induced color impression is also varied by means of the excitation, wherein the further structural color with which the first print information is formed, a color impression during exposure to the same excitation due to an induced change of an internal structure which is different from the color impression of the second print information, wherein having the structural color, and the further structural color colloidal particles, having different diameters or sizes, or alternatively or additionally, the substances in which the particles are dispersed, differ in their characteristics.