Quantifying Interfacial Metal Adhesion in Flexible Packaging Films
Quantify metal-to-polymer adhesion using ASTM F904 peel testing with EAA backing, targeting values above 60 N/m to ensure barrier stability during converting.
AIMCAL TP-105-92
Testing Protocol
Standard testing procedures for metallized substrates define how the bonding force of a thin metal layer on a flexible surface is quantified. The protocol known as aimcal tp-105-92 establishes a uniform methodology for evaluating the tape adhesion of vacuum-deposited metals on plastic and paper webs. By employing a specified adhesive tape and controlled peel angles, the procedure yields repeatable results that help packaging converters verify the quality of incoming metallized barriers.
It governs the mechanical pull required to separate the metal from the carrier web.
Evaluation Process
Mechanical action during conversion and filling lines exerts shear forces on coated layers. For this reason, the test requires a precise application of tape to the metallized surface followed by a rapid, uniform peeling action. The adhesive strength of the tape must exceed the expected bond of the metal to the substrate, allowing the operator to observe metal transfer.
After the peel occurs, the remaining surface is inspected to assign a percentage value to the metal coverage. This measurement helps production teams identify potential barrier failures.
Boundary Condition
Extremes in ambient humidity alter the chemical behavior of adhesive bonds during testing. In these wet environments, aimcal tp-105-92 ceases to provide comparable metrics because the carrier absorbs moisture. The test does not apply to non-metallized coatings or co-extruded polymer layers.