Biaxially Oriented Polypropylene Films (BOPP)

Biaxially oriented polypropylene film (BOPP) has been developed over the last 35 years and is now widely used in place of cellophane, waxed paper, and aluminum foil. The polymer used in its manufacture, polypropylene, is derived from petroleum and consists only of carbon and hydrogen atoms. The production of polypropylene is safe and energy efficient, and the product is easily and cleanly handled.

"Biaxially oriented" means that the film is stretched in two different directions. Orientation brings about several changes in the film, such as lower elongation (harder to stretch), higher tensile strength for a given thickness, greater stiffness, improved optical properties, and improved barrier to water/gases. When barrier and sealing properties are required, they can be obtained by using either of two methods: coating the film, or co-extruding layers of different materials. We use the co-extrusion process because it makes the film totally recyclable. It is also a more efficient process.

There are four general steps that are taken to produce ready-to-ship BOPP film.

  • Co-extrusion process
  • Orientation of the film in two directions
  • Primary slitting of the BOPP film
  • Secondary slitting or Metallization

Plastic waste, including BOPP film, can be recycled and reprocessed into products for many different applications. When incinerated, only carbon dioxide and water vapor are produced, with no pollution. The resulting energy released is twice the heat of coal. However, unlike paper and cellulose products, co-extruded BOPP is not biodegradable. But when used in landfill sites, plastics waste has the positive benefit of stabilizing the ground without producing unpleasant or harmful by-products.

BOPP film demonstrates excellent use of the Earth's resources. It has effective moisture barrier properties that are achieved without coatings. Because of its superior strength at low gauges, flatness, clarity, light weight and excellent printability, it has become an indispensable packaging material for a wide variety of consumer products including foods, garments, textiles, and stationary. The co-extrusion process also provides superb sealing characteristics for secure packs and good shelf life, avoiding product spoilage and waste.