Effect of Cleaning Conditions on Heat Seal Strength between 1N30-H18 Aluminium Foil and Polyvinyl Chloride Plastic Sheet

摘要

In recent years press through packaging has become more popular in the pharmaceutical packaging industry because of its remarkable advantages over traditional packaging. To sustain the practicality of press through packaging, high heat seal strength is one of the most important requirements. To obtain high heat seal strength, 1N30-H18 aluminium foil was washed with different alkaline detergents. The results showed that the heat seal strength increased with temperature in alkaline washing. In alkaline washing conditions, the heat seal strength increased in the order of alkaline detergent D, alkaline detergent C, alkaline detergent B and alkaline detergent A in the first one week but began to seriously deteriorate under washing with alkaline detergent D in the ageing test due to pitting. To obtain high and stable heat seal strength, the use of alkaline detergent should be carefully observed. The improved heat seal strength under high temperature washing, which forms hydrated pseudoboehmite, can be a result of stronger acid-base interaction between adhesive and pseudoboehmite.