What is medical injection molding?

Medical injection molding is a manufacturing process used to create plastic parts by injecting heated material into a specific mold to produce medical devices. Molding of thermoplastic material is done in an ISO Class 8 clean room environment where temperature, humidity and air filtration are constantly monitored to ensure a proper environment for part traceability and compliance.

What are the benefits of choosing injection molding for medical devices?

  • Produce complex parts and achieve part precision through tight mold tolerances
  • Enhanced strength and durability of plastics
  • Flexibility of part design for a robust end product
  • Attain consistent quality through a repeatable process
  • Incorporate multiple plastic materials seamlessly
  • Limit human interaction with automation
  • Gain efficiencies through high volume/high cavitation


What considerations should be taken into account?

  • Medical molding requires consistency and cleanliness, which is why it’s important for a molder to be certified in key compliance measures:
    • ISO Class 8 clean room: This is one of the most common clean rooms and has an average of 10-25 air changes per hour to ensure optimal compliance measures for the parts being molded.
    • FDA-registered, ISO 13485-certified facility: The manufacturing facility maintains systems and proper documentation that establish and outline the processes used throughout the manufacturing process.
    • Installation Qualification (IQ), Operational Qualification (OQ), Performance Qualification (PQ) validation: IQ, OQ, PQ are specific protocols that validate that the equipment being used to produce parts adheres to a high degree of consistency and quality assurance.


Different processes offer different advantages. Here are the ways we can optimize your medical molding project:

Multi-Shot Molding

Mold plastic parts with two or more materials or colors in one operation.

Insert Molding

Create a strongly bonded, integrated part by molding material around an insert piece for enhanced component reliability.

Stack Molds

Increase the output of an injection molding machine using multiple parting lines capable of producing multi-cavities or a family of parts in one cycle

Robotics & Automation

Mitigate the risk of part contamination with production cells that rely on robotics and automation from start to finish during the molding process.

What plastics are used when creating medical devices?

Determining the right material is essential. We’re skilled at recommending the right material that will yield the most effective result for the part. Examples of medical-grade resins EVCO uses include:

  • PP9074 MED: This is a highly clarified, random copolymer resin designed for injection molding of medical devices that’s suitable for sterilization by high-energy radiation.
  • PP D115A Natural: A multipurpose resin that has good color and process stability.
  • Profax PP 6523 Natural: This resin is heat-aging and stress-crack resistant.
  • 825P1 HIPS: An FDA compliant, USP Class VI resin.
  • Kresin KR01: This resin is ideal for medical devices that have high clarity and stiffness, and is also warp resistant.

What are some examples of use to create medical products/parts?

We’re able to manufacture and assemble most complex parts, and these are just a few of the medical components we specialize in:

  • Blood delivery housings
  • DNA components
  • Microfluidics
  • Dental products
  • Medical devices
  • Surgical instruments
  • Healthcare components and devices

How do I know if my part can be molded?

  • EVCO designers and engineers utilize an approach called “Design for Manufacturability” (DFM). This is an interdisciplinary team effort through which design goals and concepts are thoroughly reviewed to make sure that the part is molded as efficiently as possible. The DFM process helps mold makers and manufacturers ensure product quality, durability and cost efficiency.
  • DFM is important because the design planning stage is the most opportune time in the development process to consider how the end user wants the product to function. A better understanding of how it will be used allows for a more robust design, provides a higher quality advantage and ensures efficiency.

When plastics matter to your business, we’re here to collaborate and create with you. Partner with EVCO Plastics and learn how together we can take your project to the next level.