Telsonic Launch Packaging Technology Group

Ultrasonics generates material and costs savings

The packaging market is extremely diverse both in products and packaging types, with bags, pots, pouches, cartons, cups, trays and tubes all commonly used as packaging medium. In many cases, heat is used as the process for sealing the individual products and historically, whilst this has become the established process for many applications, it is not without its problems.
The heat sealing process can be adversely affected by contamination ie/ product which may have become trapped between the two sealing faces. Product which does find its way into the sealing area during the cycle can block heat transfer and result in an incomplete seal which in turn may generate a “leak path” within the seal area. Coarse particle products such as salt, sugar and coffee can also damage or puncture the packaging if they become trapped within the sealing area. Other issues frequently encountered when using the traditional heat sealing process include; liquid foaming across the seal path in beverage applications, odours being generated by product which becomes trapped between the seal faces and unsightly burnt edges. Applications with short cycle times, especially where complex laminate materials are used, also pose a risk that the seal does not have sufficient time to bond and cool causing packages or cartons to re-open with resultant leaks and spillages.
The ultrasonic welding process brings a number of significant benefits to sealing and joining applications within the packaging industry. The ultrasonic process also ensures that any heat generated is focused precisely within the seal area. Ultrasonics effectively “pushes” any trapped product out of the sealing area, ensuring predictable seal integrity and eliminating “leak paths”. The vibration and pressure used for the ultrasonic process generates localised heat from within the material itself, which contributes significantly to the reduction of odours produced during sealing, and minimises changes to the taste, aroma or appearance of the product.

Considerable energy savings can be realised where ultrasonics is used, when compared to traditional heat sealing systems. As there is no pre-heating required, the ultrasonic process is immediately available upon line start-up and the extremely short ultrasonic pulses used result in low energy consumption. The characteristics of the process, combined with process compatible materials, provide opportunities for a reduction in “head space” on packages, which in turn can generate considerable savings on the amount of material used, reduce wastage and ultimately generate significant cost savings.

Ultrasonics with a twist – sealing “peelable” polymer film and coated foil closures
The attributes and benefits of the ultrasonic process are further enhanced by a unique Telsonic innovation, Soniqtwist®, which is particularly appropriate for packaging applications on single serving products. The Soniqtwist® concept uses small, reciprocating torsional amplitudes, at the perimeter of the seal to produce the weld. The shape of the pot need not be circular and non regular shapes can also be welded. With such small rotational amplitudes at the seal perimeter, and virtually no movement at the centre of the product, this process is ideal for welding coated foil or film to the rigid pot. The Soniqtwist ultrasonic welding concept produces a highly aesthetic finish and gives excellent “peel-ability” on the finished product whilst offering the main benefit of welding through product contamination on the pot lid weld area. The Process concept also does not cause a diaphragm effect or induce perforation on thin closures. Gable topped cartons, produced from thermoplastic coated board, as used for milk, fruit juices and other beverages, is an excellent field proven example where ultrasonic sealing excels. This type of packaging requires the seal integrity of both the seam and spout attachment to be extremely high to maintain the quality of the product within the carton and ensure that there is no leakage during subsequent product handling and storage. Furthermore, ultrasonic welding is commonly used on the integral tamper proof break off tab often found adjacent to the cap on many cartons.

The attributes of process control, speed and consistency provided by ultrasonics, together with Telsonic’s innovation in hardware design, has led to a significant growth in the use of the technology by many leading packaging brands and machine builders for this type of application.
The new business unit will work closely with all packaged product manufacturer’s, material suppliers, machine builders and end users to provide a coordinated approach, building upon Telsonic’s already extensive experience and establishing the benefits of the technology across a broad range of packaging types and applications.