The invention relates to a security paper with at least two types of mottled
fibers, which differ in terms of their luminescent characteristics and form a code.
In each case one type of mottled fibers is present in a defined subarea of the
security paper, and the code is represented by the defined geometric arrangement
of the subareas on the security paper and/or by the presence or absence of mottled
fibers of a specific type.