PAPER SECURITY WITH AUTHENTICITY MARK

摘要

PCT No. PCT/DE81/00082 Sec. 371 Date Oct. 23, 1981 Sec. 102(e) Date Oct. 23, 1981 PCT Filed May 29, 1981 PCT Pub. No. WO81/03511 PCT Pub. Date Dec. 10, 1981.Security paper with authenticity characteristics embodied therein or printed thereon which are both ferrimagnetic and also only slightly absorbed in the infrared spectral region. The presence of both properties at the same position on the security paper is tested, wherein both tests can preferably be carried out simultaneously. Materials which show this rare combination of properties are some ferrites, ferrimagnetic garnet compounds and the so-called green ferromagnetic compounds.