Prior to the invention of plastics and plastic films, flexible packaging machinery was confined to creating products from paper, cellophane and glassine.
When plastic films were introduced in the early 1950s machinery manufacturers and packagers had no choice but to have their equipment adjusted/modified to accommodate/handle the diverse attributes/characteristics of such films.
Today – many of the aforementioned packaging machines currently being operated are essentially hybrids of these predecessors that are furnished/modified to deal with plastics. On the other hand, newer equipment is being designed particularly with the intended purpose of making them suitable for plastic films.
From the standpoint of machinery, there are three major differences between paper-based and plastic films: #1 stretchability; #2 stiffness; and #3 heat sealability.