Understanding Extrusion and Co-Extrusion: The Achilles USA Advantage

Understanding Film Extrusion: How It Works

Film extrusion is a continuous manufacturing process where thermoplastic resins are heated, melted, and formed into thin, flexible sheets. The process starts by feeding plastic pellets or granules into a heated barrel equipped with a rotating screw. As the material moves through the barrel, it melts and becomes a uniform, viscous liquid.

The molten plastic is then forced through a specially designed die, which determines the shape and initial thickness of the film. From here, the process diverges into two main methods: blown film extrusion and cast film extrusion.

Blown Film Extrusion

In blown film extrusion, the molten plastic is pushed through a circular die to form a continuous tube. Air is blown into the tube, inflating it into a bubble that stretches both vertically and horizontally. This creates what's called biaxial orientation, which improves the film's strength and durability.

The bubble is cooled by air rings positioned around it, then collapsed and wound onto rolls. Blown film is known for its toughness, puncture resistance, and balanced strength in all directions.

Cast Film Extrusion

Cast film extrusion uses a flat, narrow slot die to produce a wide sheet of molten plastic. This sheet is immediately passed over chilled rollers that rapidly cool and solidify the film. Cast films typically offer superior optical clarity, consistent thickness, and a smoother surface finish compared to blown films. They're ideal for applications requiring high transparency or printability, and that's the manufacturing process used by Achilles USA to produce our plastic films.

What Is Co-Extrusion? Taking Performance to the Next Level

Co-extrusion is an advanced manufacturing process that combines two or more different polymers into a single, unified multilayer film. Unlike lamination, which bonds pre-made layers together after production, co-extrusion creates all layers simultaneously as the film is formed.

Each polymer is melted in its own extruder, then fed into a shared feedblock and die assembly. The materials are carefully layered inside the die and exit as one cohesive structure. This seamless integration eliminates the risk of delamination and contamination that can occur with laminated films.

At Achilles USA, we offer 1 to 5 layer co-extruded plastic film using up to four different materials in a single run. Our cleanroom extrusion capabilities include automated thickness control and in-line optical defect inspection, ensuring precision and consistency across every roll.

Key Benefits of Co-Extruded Plastic Film

Co-extrusion allows you to engineer each layer for a specific purpose. For example, the outer layer might provide UV protection or printability, the middle layer could offer oxygen barrier properties with EVOH, and the inner layer might deliver heat resistance or chemical compatibility. This level of customization means you get exactly the performance you need without compromising on other properties.

By eliminating the need for post-production lamination, co-extrusion reduces both material costs and production time. Manufacturers can use thinner layers of expensive specialty resins (like EVOH or Nylon) while still achieving superior barrier protection. The streamlined process also minimizes waste and energy consumption, making it a more economical choice for large-scale production.

Modern extrusion lines are equipped with automated thickness monitoring systems and real-time defect inspection cameras. These technologies ensure that every inch of film meets strict tolerances, within the target thickness. For industries like pharmaceuticals and bioprocessing, where precision is non-negotiable, this level of control is essential.

Achilles USA produces co-extruded films in a cleanroom environment. This contamination-free setting is critical for medical, pharmaceutical, and bioprocessing applications where purity, sterility, and biocompatibility are required. Our cleanroom capabilities ensure minimal extractables and leachables, protecting the integrity of sensitive materials and processes.

Types of Extruded and Co-Extruded Films

Single-Layer Extruded Films

Single-layer films are made from a single resin type and are ideal for straightforward applications where a single set of properties is required. Common uses include basic packaging, protective sheeting, and general-purpose industrial films.

Multi-Layer Co-Extruded Films

Multi-layer films combine two to five layers of different materials to achieve multiple performance goals simultaneously. These films are engineered for demanding applications such as:

• Pharmaceutical packaging requiring oxygen barrier protection and tamper resistance

• Medical devices like IV bags, wound care films, dialysis equipment, and diagnostic devices

• Bioprocessing systems, including single-use bioreactor bags, media storage, and sterile filtration

• Industrial applications needing impact resistance, environmental durability, and chemical compatibility

  
  

Applications of Co-Extruded Plastic Film Across Industries

Medical and Healthcare

Extruded and co-extruded films play a critical role in medical manufacturing, where they must meet stringent regulatory standards. Applications include:

• Single-use surgical supplies and sterile packaging

• IV bags, TPN feeding bags, and medication delivery devices

• Hemodialysis cassettes and infusion pump disposables

• Wound care chambers and DVT compression pads

  
  

Pharmaceutical and Bioprocessing

High-purity co-extruded films with EVOH layers provide essential oxygen barrier protection for sensitive pharmaceutical products. In bioprocessing, these films are used for single-use bioreactor bags, buffer storage systems, and sampling equipment.

Industrial and Construction

Industrial fabrics made from extruded films include vapor barriers, insulation wraps, welding curtains, and geomembranes. These films offer environmental durability, chemical resistance, and reliable performance in harsh conditions.

Packaging

Multi-layer co-extruded films dominate the food and beverage packaging sector, where they provide extended shelf life, barrier protection, and flexibility. The global demand for packaged foods and convenience meals continues to drive growth in this application.

Graphics and Specialty Applications

Extruded films are used for facestock materials, labels, tapes, and protective overlaminates. Their printability and surface quality make them ideal for branding and visual communication.

How to Choose the Right Co-Extruded Plastic Film for Your Application

Selecting the right extruded or co-extruded film requires careful consideration of your specific needs:

• Identify performance requirements: Do you need barrier protection, chemical resistance, flexibility, or optical clarity?

• Consider environmental factors: Will the film be exposed to UV light, moisture, extreme temperatures, or chemicals?

• Determine thickness and mechanical properties: Thicker films offer more protection, while thinner films provide greater flexibility and cost savings.

• Ensure regulatory compliance: Medical, pharmaceutical, and food-contact applications require FDA approval or ISO certifications.

• Evaluate processing needs: Will the film be printed, heat-sealed, thermoformed, or welded?

  
  

Achilles USA provides expert guidance and custom formulation support to help you select the optimal film structure for your application.

Why Choose Achilles USA for Co-Extruded Plastic Film

With decades of experience in plastic film manufacturing, Achilles USA combines technical expertise with state-of-the-art production capabilities. Our cleanroom extrusion facility features:

• Cleanroom environment for contamination-free production

• Automated thickness monitoring and optical defect inspection

• Precision-controlled multi-layer configurations (1 to 5 layers)

• Custom resin selection and formulation development

• Laboratory testing capabilities, including FTIR, GC-MS, and DSC

  
  

We partner with clients worldwide to deliver contract manufacturing solutions tailored to each project's unique requirements. From resin selection and pilot testing to full-scale production, we're here to support your innovation every step of the way.

With facilities in both the USA and Japan, we offer secure, dual-sourced production and a resilient supply chain.

Common Questions About Co-Extruded Plastic Film

What's the difference between extrusion and co-extrusion?

Extrusion produces single-layer films from a single material, while co-extrusion creates multi-layer films by simultaneously combining two or more polymers.

Can co-extruded films be used for medical applications?

Absolutely. When manufactured in a cleanroom environment with biocompatible materials, co-extruded films meet the strict requirements for medical devices and pharmaceutical packaging.

How many layers can be co-extruded?

Achilles USA offers 1 to 5-layer co-extruded films using up to four different polymers.

What materials can be used in co-extrusion?

Common materials include PE, PP, EVA, EVOH, COPE, and Nylon. Each brings unique properties like barrier protection, flexibility, strength, or chemical resistance.

Is co-extrusion more expensive than single-layer extrusion?

While initial setup may cost more, co-extrusion often reduces overall costs by eliminating secondary lamination processes and allowing thinner layers of expensive specialty resins.

Are You Ready to Engineer Your Custom Film Solution?

Extrusion and co-extrusion technologies offer unmatched versatility for creating films that perform exactly as you need them to. Whether you're developing medical devices, pharmaceutical packaging, or industrial products, Achilles USA has the expertise and capabilities to bring your vision to life.

Let's connect and explore how our custom film manufacturing can support your next innovation. Contact us today to speak with one of our specialists or request a sample.