Packages made from flexible film often use a heat-sealing process to ensure closure. The process involves joining two surfaces of film with heat and pressure across a period of time. Heat-seal problems arise when another substance partially obstructs the film-to-film contact. This substance acts as a surface contaminant. In packaging operations, the product being packaged is often the source of contamination in the sealing process. Testing heat-seal strength is a primary method for evaluating seal performance of flexible film. Test procedures require contaminant-free film samples to maintain accuracy and precision in results. This study altered the test method to explore the effects of contaminated samples. It was necessary to develop a contamination technique. The new technique applies an equal distribution of contamination for each sample. This study\u27s hypothesis is that a non-contaminated seal will be stronger than a contaminated seal. The findings supported that contamination could block film-to-film contact preventing a continuous seal, resulting in seal strengths less than a noncontaminated seal test. Results from two types of film and different seal temperatures supported the findings
