OPP film

OPP film – oriented polypropylene for versatile packaging solutions

In the modern packaging industry, OPP film plays a central role as a reliable and versatile packaging solution. As oriented polypropylene, this innovative plastic offers excellent properties for a wide range of applications – from food packaging to technical applications. The high quality and flexibility of OPP films make them an indispensable substrate in the packaging of various products.

What is OPP – oriented polypropylene film?

OPP, oriented polypropylene films, are oriented (stretched) in both longitudinal and transverse directions during the manufacturing process, thereby acquiring their desired optical and physical properties. Orientation can occur either only in the longitudinal direction (mono-oriented, so-called MOPP film) or in both longitudinal and transverse directions (biaxially oriented, so-called BOPP film), with the largest proportion being biaxially oriented polypropylene, i.e., BOPP films.

The essential difference between conventional PP film and OPP lies in its processing: While “non-oriented” PP films, so-called CPP or cast PP films, can be processed after extrusion, OPP undergoes an additional orientation process. This process leads to increased strength, improved transparency, and optimal material stability. CPP films are sometimes combined with OPP films (laminate films) to impart additional properties to the finished laminate.

In the packaging industry, OPP films are found, for example, as film packaging for confectionery, as protective film for electronic articles, or as high-quality packaging for cosmetics.

Properties and advantages of OPP films

The special properties of OPP films result from the specific orientation process and usually very complex formulations (raw material combinations). These make them a preferred material for demanding packaging applications.

High transparency and crystal-clear optics are typical characteristics regarding optical properties. This exceptional transparency makes OPP films ideal for retail packaging where product presentation is crucial. The optical properties also enhance the effect of packaging, from high gloss and transparency to matte, paper-like surfaces.

The mechanical strength significantly surpasses that of unoriented PP films, as biaxial orientation can significantly improve important properties such as film stiffness, puncture resistance, and thus general processability (profile and running properties). These properties are particularly important when used on packaging machines, where the material is subjected to high mechanical stress.

Odorless and tasteless properties make OPP films the ideal choice for packaging food products. The material does not release unwanted substances into the contents, thus ensuring the original quality of the packaged products.

The temperature resistance from -40°C to +120°C enables diverse applications – from the deep-freeze sector to warm packaging processes. This stability across a wide temperature range makes OPP films a reliable packaging solution.

Excellent sealing properties support automated packaging processes. The sealability of an OPP film is achieved through coextrusion (multi-layer extrusion with various raw material formulations) or through a coating, ensuring that tight seal seams optimally protect the packaged product within a packaging process.

Application areas and industries

The versatility of OPP films is evident in their wide range of applications across many different industries.

In the food industry, OPP films have become a standard. For foodstuffs such as candies, bakery products, chocolate, or other snacks, they offer optimal protection and appealing product presentation. Bakery products benefit from the moisture barrier, while snacks retain their freshness due to the excellent aroma barrier. Especially when packaging spices and tea, the odorless properties that prevent contamination between different products are highly valued.

The pharmaceutical and medical technology sector uses OPP films for sterile packaging where hygiene is of utmost priority. The chemical resistance and the possibility of sterilization make the material the first choice for medical products.

In the non-food sector, OPP films are found as gift packaging, flower film, protective films, capacitors, and adhesive tape. The flexibility of the material enables versatile packaging forms, while the stability and physical properties of the film offer reliable protection.

Industrial applications include labels, adhesive tape films, and technical packaging, where surface homogeneity and precise dimensions are crucial.

OPP film variants and product forms

The product range of OPP films includes various variants that differ in terms of density, thickness, as well as optical and technical properties.

BOPP (biaxially oriented polypropylene) represents the highest quality variant. Through biaxial orientation in both directions, BOPP achieves the highest stability and strength. These films are the first choice for demanding applications where maximum mechanical properties are required.

The film thickness is chosen depending on the application. Thinner films from 10µm (possibly even below) are suitable for light products such as spices, but also for technical applications like capacitors, while thicker variants well over 50µm are used for heavy or sharp-edged products or goods.

Coated variants significantly expand the application possibilities. Acrylic lacquer coatings improve sealing properties, while PVDC coatings offer additional barrier properties. Metallized OPP films combine the advantages of aluminum with the flexibility of plastic.

Special OPP film types

Antistatic OPP films protect electronic components from electrostatic discharges. These special films are indispensable for packaging sensitive electronic products.

Barrier OPP films with improved water vapor, aroma, and oxygen barrier are particularly suitable for products with a long shelf life. They offer increased protection against spoilage and other environmental influences.

Printable OPP films enable high-quality printing directly onto the film surface. These types are ideal for product presentations and branding, as they offer a uniform and high-quality printing surface.

Processing and machine runnability

The processing of OPP films on modern packaging machines requires precisely coordinated parameters and high material quality.

Optimal running properties on flowpack and other packaging machines are a decisive advantage of OPP films. The material possesses running and processing properties adapted to the respective packaging process and remains stable even under high stress, such as tensile stress or sliding friction. This ensures continuous production, even at higher speeds.

High-speed processing up to over 800 m/min is possible with high-quality OPP films. This speed enables efficient production processes and high throughput rates in industrial manufacturing, combined with lower production costs.

The custom converting includes exact sheets, rolls, and other processing. Experienced manufacturers can adapt the films precisely to customer specifications.

Quality control according to DIN ISO 9001 standards ensures consistent product properties. Regular checks of mechanical properties, transparency, and surface finish ensure consistently high quality.

The processing often requires special machine settings. Sealing temperatures, pressure settings, and transport speeds must be adjusted to the respective OPP variant to achieve optimal results.

Sustainability and recycling

The sustainability of OPP films is gaining increasing importance in the packaging industry and offers innovative solutions for environmentally conscious companies.

100% recyclable monomaterial films are at the heart of sustainable packaging concepts. Unlike complex multi-layer laminates, pure OPP films can be fully returned to the recycling loop. This property makes them a future-proof choice for environmentally conscious companies.

The reduction of multi-layer laminates in favor of recyclable OPP films is an important trend. Through innovative coating and coextrusion technologies, many barrier properties can also be achieved with monomaterials without compromising recyclability.

As an environmentally friendly alternative to non-recyclable packaging materials, OPP films make an important contribution to the circular economy. They are increasingly replacing materials that cannot be recycled or are difficult to recycle.

The contribution to resource conservation is evident in several aspects:

• Lower weight (low substrate density) reduces transport emissions
• Longer shelf life of packaged products reduces food waste
• Possibility of multiple uses in the value chain
• Reduced material usage through optimized wall thicknesses

Certified sustainable production processes ensure that environmental aspects are considered during manufacturing. Modern production facilities operate energy-efficiently and minimize waste through the recycling of production residues.

Individual consulting and solutions

The selection of the optimal OPP film requires comprehensive consulting and individual adaptation to the specific requirements of each company and application.

Material consulting helps in choosing the right film variant. Experienced consultants analyze the requirements of the products to be packaged, the packaging machines used, and the desired properties of the final packaging. This analysis leads to the optimal material selection, considering both technical and economic aspects.

The sample service and testing options on customer machines reduce risks during material changeover. Before larger quantities are ordered, customers can test the films under real production conditions. These tests reveal potential for optimization and ensure smooth production processes.

Development of customer-specific OPP film solutions enables customized packaging. Whether special barrier properties, adapted sealing parameters, or individual surface properties – experienced manufacturers also develop solutions for unusual requirements and applications.

Technical support and application consulting accompany customers even after material selection. Experts provide advice and support for processing problems, machine changeovers, or the development of new products.

The combination of high-quality OPP films, comprehensive consulting, and individual solutions enables companies of all sizes to optimally address their packaging requirements. From small special or niche applications to high-volume standard packaging, the diversity of OPP technologies offers the right solution for every requirement.

Whether for packaging fruits and vegetables, presenting high-quality cosmetics, or protecting technical goods – OPP films have established themselves as a reliable and versatile packaging solution. The continuous development of the technology and the focus on sustainability make them a future-proof choice for modern packaging requirements.