What is polypropylene?

Polypropylene is part of the polyolefin family. It is produced when many propylene molecules are joined together by a process called polymerisation. Propylene is usually extracted from Crude Oil.
Polypropylene can be made into a film which :

  • Gives excellent moisture resistance
  • Resists attack by the majority of acids, bases, salts, oils and fats
  • Non-chlorinated
  • Recyclable
  • Cost effective
What is cast polypropylene?

Cast polypropylene such as Propacast™ more commonly known as CPP is a soft film, like polyethylene. 

It is an unoriented film and therefore has lower stiffness and tensile strength compared with oriented and has lower transparency.  The unoriented nature reduces the shrinkage of the film.  CPP can be used as a mono film but is often the sealing web in complex laminates e.g. retort pouches.

What is biaxially oriented polypropylene film?

Biaxially oriented polypropylene (BOPP/OPP) film is produced when a polypropylene is stretched in both machine and transverse directions directly following extrusion.  There are two methods of production, bubble and tenter.

What are the effects of biaxial orientation?

Biaxial orientation is a process whereby a plastic film or sheet is stretched in such a way that the polymeric chains are oriented parallel to the plane of the film.

This process changes the properties :-  

  • Stiffness increases
  • Tensile Strength increases
  • Elongation reduces
  • Clarity increases
  • Gas/moisture permeability reduces

What is the bubble process?

Our unique process for producing bubble produced BOPP involves the simultaneous stretching in the machine (MD) and transverse (TD) direction, of the polymer resulting in a balanced orientation of the film, giving the same proportion in both directions (MD and TD). Bubble production allows the manufacture of thick films by collapsing and laminating the two sides of the bubble film together.

What is the tenter process?

The tenter-frame process is a sequential process in which the polymer is first melt extruded onto a cast roll, and then stretched in the machine direction (MD) and then the transverse direction (TD).

What are the differences between bubble and tenter BOPP films?

Bubble film imparts a simultaneous orientation of 8x MD and 8x TD compared to tenter film which imposes 5x MD and 10x TD sequentially.

This leads to several property differences which are exploited in different markets.

What is the structure of BOPP?

All BOPP/OPP films from Innovia are multilayer co-extruded films. Other functionality can be introduced by the application of various coatings.

Multilayer Co-extrusions

Multilayer co-extrusions such as Propafilm™ Strata films can be used to replace complex laminates with single films with different layers. Layers can give peelability, barrier to gases, moisture and aroma and cavitation (increasing the m2 per Kg.)

When should a coated film be used?

Coatings are usually used when an improved barrier to oxygen, moisture, flavour or aromas is required. In addition, some coatings have a low seal threshold which allows faster running on packaging machines. Many coatings also give superior gloss to enhance pack aesthetics.

What type of coatings can be applied?

PVdc coatings can be applied if a high oxygen barrier is required. Acrylic coatings give aroma barrier and superior gloss as well as a reduced heat sealing threshold. FFF coatings are used for a very low heat seal threshold. Films with differential coatings can be produced. Print primer coatings are used extensively in the labels industry.

Can BOPP film be printed?

Yes, BOPP/OPP films are suitable for use with standard and digital printing techniques with a wide range of different inks. Please consult our Technical Department for more details.

Why are the barrier properties of a film important?

The films barrier properties are vitally important as it is necessary to match the needs of your product to the most appropriate packaging film. This will ensure your product is kept in the best possible condition when packaged which will extend shelf life, reducing food waste and carbon emissions.

We have a range of films that provide barriers to moisture, oxygen, flavours, aromas, mineral oil and UV light. Please consult our Technical Department if you require more information.

Does Innovia have films that are suitable for lamination?

Yes we have a range of BOPP/OPP films that are suitable for lamination. Please consult our Technical Department for more details.

Why is the slip of a packaging film important?

The slip properties of a packaging film (Coefficient of Friction) are important as the film needs the correct slip levels to be able to run efficiently on a packaging machine.

Are the films food contact approved?

The majority of our BOPP/OPP packaging films are food contact approved. We are able to provide a Declaration of Compliance for each film which gives details of the film’s regulatory compliance. Please consult our Technical Department if you require a copy of these documents or if you require more information on the subject.

How can I select the best product for my application?

Matching the correct film to the product application is essential, both to guarantee the functionality you require and to maximise potential shelf life.  

The Markets and the Product sections of this website are designed to help you choose the correct product for your application. However, should you require further guidance, please do not hesitate to contact your nearest Sales Office listed under Contacts or our Sales and Marketing Department in order to discuss your requirements.

What thickness BOPP can Innovia provide?

Innovia Films offer a choice of standard thicknesses ranging from 15 microns through to our collection of Labels films with thicknesses of up to 130 microns.

What widths can Innovia provide?

Innovia Films has the capacity to provide slit reels in a variety of sizes, from a narrow 30mm up to reels with a width of 2600mm.

Please be aware that, although we endeavour to meet customer requirements wherever possible, the need to utilise the full width of the master reel must be considered.

Please contact your local Sales Manager to discuss whether the widths you require are available in your chosen grade.

Is it possible to receive A4 samples of your film?

We maintain a stock of BOPP film grades cut to A4 sized sheets.

Please consult the Library section of this site and review the datasheet library area to determine the film types you think would fulfil your requirements. Then complete the contact enquiry form if you would like to receive any A4 samples.

Are there alternatives to crude oil in the production of BOPP?

Yes, we have a fully functional recyclable BOPP film range named Encore, which can be manufactured from renewable non-food based materials which lowers carbon footprint and reduces the use of fossil based resources.

Encore films are managed through ISCC PLUS. The ISCC (International Sustainability & Carbon Certification) is a globally applicable sustainability certification system that covers all sustainable feedstocks.

Do Innovia Films’ OPP products contain any recycled content?

With waste minimisation in mind, Innovia Films recovers its coextruded material rejects and reprocesses those as standard practice.

Our Encore range of films can also be produced using 30% chemically recycled post-consumer raw materials which mean that they are fully food contact compliant and recyclable. They are also able to meet the recycled content legislation.

The properties of Encore films are identical to the equivalent fossil based films. These films are also managed through ISCC PLUS certification.

What are the end-of-life options for polypropylene films?

Polypropylene can be readily recycled. It is more resistant to degradation during mechanical recycling compared with other polymers e.g. PE which gives much greater potential for future high value products.

When collected BOPP/OPP film can be sorted and mixed with the existing PP recycle stream ensuring a full circular economy.

Most of Innovia’s uncoated, acrylic coated and EVOH films have been independently certified recyclable by Interseroh a German recycling and consulting company.