Flame Treatment is a process commonly used on plastic containers to improve the adhesion of pressure sensitive labels. This process results in oxidation on the surface of containers manufactured from polyethylene and polypropylene by chemically changing the surface, providing a more suitable surface for the application of pressure sensitive labels. Flame treatment provides a surface similar to that achieved by corona treatment. Although beneficial for label adhesion, the process has a detrimental effect on the land area of the container with respect to induction sealing. This is particularly apparent when a weld type seal is desired. For example, when a polyethylene-faced liner is being sealed to a flame treated container the seal strength and the force required to remove the seal will be quite variable. Variability in the intensity of the flame treatment process will result in a wide range of seal strengths. Please note, the higher the intensity of flame treatment on the land area, the weaker the seal strength. Excessive flame treatment can result in a poor bond or in extreme cases no bond whatsoever. If this situation developes, please contact the container supplier and determine the level and method of flame treatment.