At United Silicone, we are often asked about alternatives to Teflon tape in the heat seal process. Luckily, we have some great options. To better understand why these choices are so compelling- we will take a look first at how Teflon tape is used in the heat seal process.
To achieve highly repeatable seal integrity on heat seal lines it is essential to ensure that your silicone does not become “gummy” and stick to your lidding film. It is also important to ensure that no granular residue from your packaging line sticks to your lidding film. These are the most common reasons why heat seal line operators turn to Teflon tape or Teflon cloth.
So why is it that many heat seal lines turn to Teflon tape or Teflon cloth? They want to ensure critical heat seal components are protected and that nothing is sticking to their lidding films (which would endanger seal integrity).
Some silicone can become gummy or sticky when subjected to the high temperatures and pressure applied in the hot stamping process. Teflon tape keeps this stickiness from damaging the lidding field. Sometimes seals are compromised by very fine particles becoming stuck to the lidding film- again Teflon can help prevent this from happening. To ensure silicone doesn´t become gummy and that fine particles do not stick to lidding film- heat seal line operators often wrap their silicone seal bars in either Teflon tape or Teflon cloth.
Teflon tape has several significant disadvantages. The most important of these drawbacks relate to operator safety and downtime. It is not easy for line operators to change the Teflon tape or Teflon cloth applied to silicone seal bars. Devices can reach temperatures of over 300 degrees F. There is a significant burn risk for operators who must frequently handle such high temperature components. The safety gloves operators must wear in response to this burn risk makes unscrewing the seal bar screws, removing the worn Teflon tape or Teflon cloth, replacing it with new Teflon tape or Teflon cloth and then carefully re-screwing the small seal bar screws and tedious and time consuming task. On average this can take anywhere between 20-40 minutes. Since the Teflon tape must be replaced frequently, this tedious process must be repeated frequently.
Luckily- there is a better way. Even better news is that there are TWO better ways. The better, safer, more efficient way to ensure seal integrity is to use Engineered Silicone Formulations and in some instances- Teflon-Bonded Silicone.
Engineered Silicone Formulations are specially designed to withstand the extreme heat and pressure required for heat sealing – WITHOUT becoming gummy or sticky. United Silicone´s silicone formulations are able to withstand the high pressure required for seal integrity and are heat tolerant up to 550 degrees Fahrenheit. For 90% of cases- Engineered Silicone Formulations are all that are needed for hassle-free, non-stick heat seal performance.
Particularly when packaging granular products where small particles may compromise seal integrity and stick to sealing films, Teflon can help. Teflon-bonded silicone is a new and improved alternative to Teflon tape. Teflon-bonded silicone seal bars can inserted and changed in a fraction of the time required for Teflon tape changeovers.
Teflon-tape is replaced frequently on a typical heat seal line running at average speeds. High volume lines will often do this once every shift. Lower volume lines may change Teflon tape 2-3 times per week.
Typically- removing and replacing Teflon tape will take on average 20-40 minutes whereas changing a Teflon bonded Silicone Seal Bar will take under 5 minutes.
Teflon-bonded silicone is a tremendous resource as a safer, faster way to achieve superior seals.