Ultrasonic welding process used in mask production

Masks have become an essential consumable in our lives. The core material of mask is melt-blown cloth. How to make a mask? In fact, the mask is manufactured using an ultrasonic welding process. Ultrasonic welding uses high-frequency vibration waves transmitted to the surfaces of two objects to be welded. Under pressure, the surfaces of the two objects rub against each other, forming a fusion between molecular layers.

When ultrasonic waves are applied to the thermoplastic's contact surface, the mask is dotted with indentations, such as seals, ear bands and exhalation valves, that are welded by ultrasonic waves and generate tens of thousands of high-frequency vibrations per second. This high frequency vibration of a certain amplitude will transmit ultrasonic energy through the upper weldment to the welding area. Due to the high acoustic resistance at the interface between the two welding zones, local high temperatures are generated.

In the production process of masks, we can intuitively understand the welding of all-plastic nose bridge strip, welding after folding, breathing valve welding, multi-layer welding and ear band welding, which can be completed by ultrasonic welding process.