VEILIGHEIDSPAPIER.

摘要

Security Paper Security paper which immediately reveals an attempt to alter handwriting thereon by the use of an alkaline ink remover and which is characterised by the incorporation therein of a pyrenesulphonic acid or a metal salt thereof, particularly an alkali metal or alkaline earth metal salt. Security paper incorporating such an acid or salt exhibits a fluorescent colouration when contacted with an alkaline ink remover.