Biaxially-oriented polypropylene, better known as BOPP, has become the film most required by the flexible packaging industry and is gaining ground to the rigid plastic, given its versatility, economic gains and sustainability.
What is Biaxially-oriented Polypropylene (BOPP)?
It is a polypropylene film with a coating that allows it to be heat sealed. Its main feature is the protection barrier it offers to prevent the entry or exit of moisture. It increases strength and clarity. Its applications are mainly oriented to the mass market of cookies, snacks, chocolates, candies, labels (laminated and printed generally), fresh products and confectionery products. Other typical uses include, the wrapping of CD’s, DVD’s, and cigars.
A large majority of food producers choose biaxially-oriented polypropylene to pack their products, given their high barrier of protection against moisture, higher yield per kilo and low cost. Many packers, even, are replacing rigid containers with BOPP.
It is easy to coat, to print, and the lamination gives the appearance and properties necessary for its use as a packaging material. This process is usually referred to as the conversion. It is normally produced in large rolls that are cut longitudinally in peripheral machines in small rolls for use in packaging machines or in other applications.
Protection and aesthetics
The protection function or barrier can be extended, depending on the product, up to six months. For longer shelving times, the BOPP must be combined with other high-tech films such as polyester, polyethylene, aluminum or paper. There are around twenty variants that allow to achieve a high quality packaging, high protection barrier or with special textures.
There are different types of BOPP to increase the visual impact of the product and, in the case of metallised, its protection function:
Metallic standard barrier
High barrier metallised
Each product has at its disposal, a biaxially-oriented polypropylene film to develop the flexible packaging suitable to its characteristics:
Biscuits: laminations of BOPP / BOPP in different thicknesses and in combinations with white or metallic BOPP. Excellent maneuverability in both Flat End and Flow Pack lines.
Candies and sweets: laminations of BOPP / PE protect the product from moisture given its sugar content.
Labels: roll label for soft drinks, waters and other bottled products. With laminations BOPP13U / BOPP 38 PB or simple sheet of BOPP PB 40.
High transparency and brightness
Good mechanical properties
Easy to process (printing, lamination)
Good machinability in the packaging lines
Excellent water vapor permeability
Wide range of thicknesses
Different seal temperatures
Different levels of COF
Cavities with different densities
Good cost / performance ratio
This material has the facility to be printed in flexography or gravure. In addition, it can be recycled with or without printing, and allows to make plastic sheets or pellets for buckets, pots and all kinds of rigid plastics for molding.