From product quality to output speed, uptime and design – sealing has a direct impact on food safety and brand image. However, whether a seal is effective or not depends on how suitable the technology is for each individual product, production parameters and films.
Norbert Hoechst is expert for packaging materials at Bosch Packaging Technology. In a brief interview he explains why finding the right technology is key and what options manufacturers have today.
Why is sealing so important in packaging?
Manufacturers need to carefully balance performance, product protection and pack style requirements in order to achieve optimal production results. Appealing packaging boosts consumers’ trust in the brand and the product itself. The consumer experience already begins with the product’s packaging, so, ideally, it should reflect the desired brand image. But, of course, it’s not all about aesthetics – in order to protect the product, packaging needs to be airtight, which is where sealing technology comes into play.
What are the most important requirements for manufacturers?
It really comes down to these deciding factors: quality, efficiency and cost. Solutions that utilize cost-efficient films, that guarantee tight seals and long-lasting packaging are particularly popular. Of course, it’s of the uttermost importance that waste throughout the production process is kept to a minimum and that production cycles are as long-lasting as possible.
What sealing technologies are available? Which ones are suitable for which application?
The key technologies are heat, cold and ultrasonic sealing. Depending on the product’s heat sensitivity and the package’s desired tightness, sealing time plays an important role, too.
Chocolate products, for example, are heat sensitive, so we recommend cold sealing technology. Rotating cold sealing technology is very cost-effective and enables high production speeds and average air tightness.
Biscuits, on the other hand, are not sensitive to heat, so the use of heat sealing technology is prevalent. Compared to cold sealing, the heat sealing process is a bit slower. For maximum production performance, we not only push for increased heat sealing speeds – of up to 100 meters per minute at present – but also see the potential for cold sealing applications for biscuits. For heat sensitive products that require hermetically tight seals, ultrasonic sealing technology represents an interesting alternative.
What are the most important considerations with regard to sealing films?
The product and desired pack style are at the center of any decision. This determines the choice of film, the sealing jaw profile and necessary sealing time. In general, we try to find the ideal balance between quality, performance and cost. And here’s the good news: innovative sealing technologies now facilitate the use of more cost-effective alternatives. For example, amplified heat sealing can be utilized with less expensive heat sealing films.
How can sealing technologies safeguard quality, storage and transportation challenges in hot and humid climates?
In hot and humid climates, for example in Asian countries, cold sealing methods can be problematic. If the films are transported and stored without air conditioning, their quality is impacted, which makes for faulty seals and, therefore, an increase in waste. Cold sealed seams can come undone in this climate, which can ruin the product. Heat sealing offers a more robust seal in these climatic conditions. In case heat sealing cannot be used ultrasonic sealing offers a good alternative.
Sealing technologies at a glance:
Standard Cold Sealing: https://www.youtube.com/watch?v=FUDfZt1D9_g
Standard Heat Sealing: https://www.youtube.com/watch?v=58eOeNkvl0I
Amplified Heat Sealing: https://www.youtube.com/watch?v=Ef1l1_XTBlY
Long-Dwell Sealing: https://www.youtube.com/watch?v=raGCEkxGoms
Ultrasonic Sealing: https://www.youtube.com/watch?v=e8arogQJoJE