PRESSURE-SENSITIVE ADHESIVE SHEET CAPABLE OF DISCRIMINATING PEEL HISTORY

摘要

PURPOSE: To obtain a pressure sensitive adhesive sheet capable of visually discriminating peel history by shifting the position of a pattern in the case of re-adhesion by arranging a discrimination mark formed from an uncured ink layer to the upper or lower layer of the pressure-sensitive adhesive layer formed on the adhesion scheduled part of a base material sheet. ;CONSTITUTION: A pressure-sensitive adhesive sheet is obtained by forming a pressure-sensitive adhesive layer on the adhesion scheduled part of a base material sheet 1. In this case, a discrimination mark 3 formed from an uncured ink layer is arranged to the upper or lower layer of the pressure-sensitive adhesive layer 2. When the pressure-sensitive adhesive sheets are closely bonded by the pressure-sensitive adhesive layers 2 and subsequently peeled, the discrimination mark 3 is damaged. When the pressure-sensitive adhesive layers 2 are re-bonded so that patterns coincide mutually and subsequently re-peeled, patterns become double and it is cleared that there is peel history. Therefore, in a mail medium concealing secret data, the pressure-sensitive adhesive sheet capable of visually discriminating peel history can be obtained.;COPYRIGHT: (C)1994,JPO&Japio