Ultrasonic sealing for food and confectionary

Bosch Packaging Technology has introduced ultrasonic sealing technology for vertical form, fill and seal machinery for use in food and confectionery packaging applications. Ultrasonic sealing is a method for joining thermoplastic materials together by emitting acoustic vibrations, creating a tight, strong seam for closures in doy-style stand-up pouches, gusseted and pillowbag packaging formats.

Bosch’s ultrasonic sealing technology is an alternative to heat sealing, and can process conventional heat sealed packages, such as those composed of polypropylene and polyethylene film. With the ultrasonic process, the packaging film is sealed with heat from friction generated by an oscillating tool, eliminating the need for direct heat contact.

Typical heat sealing systems often require cleaning as the product tends to melt and accumulate in the sealing zone. The ultrasonic process can seal film structures that have been contaminated by product minimising stoppages, reducing downtime. By removing the heating element in the sealing process, manufacturers can potentially reduce the thickness of sealant layer of packaging film structures, reducing material costs. Removal of the heating element also enables ‘cold’ packaging of sensitive products which is particularly useful in confectionery, grated cheese, fresh produce and frozen food.

Bosch’s ultrasonic sealing technology is capable of web material speeds used on vertical form, fill and seal machines and offers possible sealing time reduction. Seams can be immediately subjected to product load after joining, reducing processing times. Ultrasonic sealing can be more precisely calibrated than heat sealing. Operators are able to adjust oscillating frequency, ensuring a reproducible seal. Additionally, processing parameters can be saved and recalled and the joining process can be validated.