Pressurex pressure-indicating sensor film

Ultrasonic welding is used in packaging for many everyday items, including sealing containers, tubes and blister packs.

To optimise the strength of a weld and prevent defects which would cause leakage or spoilage, the horn and anvil must be precisely aligned during set-up so that the horn exerts uniform pressure across the entire weld area. To ensure this happens, Pressurex pressure indicating sensor film was designed.

Routine use of the film during the set-up of ultrasonic welders helps ensure proper contact pressure and alignment between the horn and anvil, which results in welds of greater bond strength and aids in reducing rejected product and lowering base factory cost.

When placed between the horn and the anvil of the ultrasonic bonder, Pressurex instantaneously and permanently changes colour directly proportional to the actual pressure applied. The precise pressure magnitude (PSI or kg/cm²) is then easily determined by comparing colour variation results to a colour correlation chart (conceptually similar to interpreting Litmus paper).

These pressure maps show pressure variations across the weld zone which can result in less than optimal weld strength. Such variations are generally caused by lack of alignment between the horn and anvil or by dirt or residue on the horn.