Before it’s ready to hit the shelves, packaging tape must pass a series of rigorous tests to ensure that it can meet the demands of the job it was designed for and maintain a strong hold without failing.
Many test methods exist, but the major test methods are performed during the Physical Testing and Application Testing processes of the tapes.
Performance testing of packaging tape is regulated by the Pressure Sensitive Tape Council (PSTC) and the American Society of Testing and Materials (ASTM). These organizations set the standards for quality testing for tape manufacturers.
Physical testing examines the tape’s physical properties of peel, tack and sheer – three characteristics which are balanced to produce quality packaging tape. Some of these tests include:
- Adhesion to Stainless Steel: measures the amount of force it takes to remove the tape from a stainless steel substrate. While packaging tape is not likely to be used on stainless steel, testing on this material helps to determine the tape’s adhesive properties on a consistent substrate.
- Adhesion to Fiberboard: measures the amount of force required to remove the tape from fiberboard – the material that it will most likely be used on for its intended application.
- Shear Strength/Holding Power: the measure of the adhesive’s ability to resist slippage. This is critical in carton sealing applications as the tape tabs are under constant force from the memory in the major flaps of the carton, which have a tendency to want to return to an upright position.
- Tensile Strength: the measure of the load that the backing can handle up to its breaking point. Tape is tested for tensile strength in both the transverse and longitudinal directions, meaning across the width of the tape and across the length of the tape, respectively.
- Elongation: the percent of stretch incurred up until the tape’s breaking point. For best tape performance, elongation and tensile strength must be balanced. You wouldn’t want a tape that is too stretchy, nor one that does not stretch at all.
- Thickness: also called the gauge of a tape, this measure combines adhesive coat weight with the thickness of the tape’s backing material to yield an exact measure of a tape’s overall thickness. Higher grades of tape have a thicker backing and a heavier adhesive coat weight for heavy-duty applications.
Application testing can vary between manufacturers, and can be customized to fit the intended application of different types of tapes.
In addition to testing for product specifications, packaging tapes are tested to determine how well they fare in transit. The International Safe Transit Authority (ISTA) regulates these types of tests, which often include drop tests, vibration testing that simulates the movement of product on a truck, temperature and humidity testing to determine how well the tape and its packaging hold up in unconditioned spaces, and more. This is extremely important because if the tape can’t survive the supply chain, it doesn’t matter how well it would have performed on the packaging line.
Regardless of the type of packaging tape you require for your application, you can be certain that it has been put to the test to make sure it stands up to the manufacturer’s quality claims and the PSTC/ASTM standards they are subject to.