It is undoubtedly fair to say that one of the key sectors driving innovation in the area of micromolding is the medical device industry. Demand for minimally invasive curative and diagnostic procedures is growing exponentially, and because of this, medical device manufacturers have been designing (and seeking to manufacture) smaller and smaller components, with thinner walls, and complex and miniature features. Couple this with the overarching demand from patients and healthcare providers to rationalize the costs associated with medical treatment, and medical device OEMs are constantly on the lookout for cost-effective and efficient manufacturing processes.

Shrinking Sizes, Not Shrinking Profits

The heat is on for medical device OEMs to maintain profitability despite downward pressure on prices, and this will be achieved as the decade progresses through the development of innovative products that will fulfill the evermore exacting requirements of endusers. Demand will increasingly be for versatile devices that will embrace the potential for “smart” diagnostics and treatment presented by the proliferation of so-called “big data” and devices that provide cheap alternatives to traditionally used but expensive diagnostic and therapeutic devices.

Micromolding is used by many medical device OEMs to achieve their exacting manufacturing requirements. It is a technology that can produce tiny, complex, and feature-rich components efficiently, cost-effectively, and in volume. In fact, it is not overstating the case that the correct use of micromolding technologies is what gives successful medical device OEMs competitive advantage and drives product innovation and profitability. Micromolding can provide high-quality parts with high dimensional accuracy, which is crucial for sensitive medical applications such as specialist devices for cancer treatment and diagnosis, small molded catheter tips, microneedles, small surgical instruments, dental implants and infection control devices, and staples, to name but a few.

Micromolding Today

Micromolding can produce tiny, complex, and feature-rich components efficiently, cost-effectively, and in volume. (Credit: Accumold)

Advances in material development — with the introduction of high-performance polymers that have enhanced strength characteristics, toughness, thermal properties, and chemical resistance — mean that many medical device OEMs are looking to micromolding.

Throughout history, medical advances have been made due to technological innovation, and micromolding can be seen as the latest technological innovation that enables the design, manufacture, and clinical use of groundbreaking medical devices. Not only does the technology allow for the manufacture of complex micro parts, but manufacturing in plastic in many cases reduces part cost, reduces weight (a key consideration for the medical sector), and allows for functioning products to be made using fewer overall components, which in turn reduces assembly time and cost.

For the U.S. medical device industry, which functions with frequent hikes in taxes levied on the sale of medical devices, and with the increased power and purchasing muscle of group purchasing organizations (GPOs), any technology or manufacturing solution or process that allows for the attainment of product functionality while reducing costs is welcomed. It is here that micromolding finds its sweet spot. The use of such cost-effective and sophisticated technologies will help to mitigate the pressures on the profitability of medical device OEMs.

With Innovation Comes Complexity

Medical device manufacturers have been designing (and seeking to manufacture) smaller and smaller components, with thinner walls, and complex and minute features. (Credit: Accumold)

Micromolding in the medical device sector, however, is often not straight-forward. In the area of material usage, for example, micro medical devices often require the integration of different materials, such as thermoplastics, biocompatible metals, and silicones. Micromanufacturing solutions often lean toward the use of complex secondary assemblies and overmolding techniques, all of which require an innate understanding of the processes — especially a knowledge of the bonding and compatibility of different materials — and the use of state-of-the-art manufacturing technologies.

For any medical device OEM seeking to work with such exacting technologies and procedures, it is vital that they locate and work with experienced micromolders that are aware of, work with, and are experienced in troubleshooting the implications of tool design, material choice, and the numerous processing complexities that exist in the area of micromolding.

Key to success is that medical device OEMs do not just view their chosen micromolder as a job shop, but rather that they partner with the molder at the earliest possible point in the design-to-market process in order to avoid costly mistakes, and that requirements for multiple iterations of product design and even tooling as solutions to micromolding problems are sought. Micro medical plastic product manufacture requires that the relationship between OEM and micromolding specialist is a true partnership, but often runs differently from a traditional OEM/supplier relationship. In micromanufacturing, most of the mission-critical issues occur at the design and prototyping stage of product development. This can and often does include material choice and even packaging considerations. A true partnership will ensure faster time to market with more efficient and lower cost products.

Key Partner Attributes

Micromolding for medical device OEMs is an art form honed after years of expertise and troubleshooting, and it is vital that micromolders have the business culture, personnel, and equipment in place to provide the service necessary to ensure a successful project outcome. Micromolders for medical device OEMs will be dealing with low-, medium-, and high-volume runs in a variety of different materials, all requiring different levels of validation. They must also have the expertise in handling, storing, and processing often extremely expensive and sensitive materials that in many instances will be used in critical implantable applications.

Knowledge of State-of-the-Art Equipment. The transition from injection molding machines that can effectively produce “small” parts, and machines that can produce “micro” parts and features is important, and micromolders must be able to utilize state-of-the-art equipment designed for exacting micro applications. There is high degree of control and repeatability necessary in micromolding where parts with weights less than 0.05 g are standard, and this requires detailed understanding of the micromolding process.

Tooling. It is in the area of tooling for micromolded medical parts that time and money can be wasted if the micromolder does not have the expertise required. Tooling for micromolding projects does not require an extrapolation of the rules governing tooling in traditional injection molding. Features in micromolded parts often exceed the allowable tolerances in traditional injection molding, and micromolders must be in a position to employ an array of technologies, including the latest CNC machining technologies as well as electrical discharge machining (EDM).

Other tooling issues specific to micromolding include heating and cooling implications when dealing with extremely thin steel inserts that can be negatively affected by temperatures involved in many medical molding applications. As many medical applications use high-temperature, high-performance materials such as bioresorbables, liquid crystal polymers, and PEEK, it is necessary to use and understand the nature of tooling materials, such as stainless steel, rather than traditional tool steels that may not be able to withstand the high temperatures necessary and can also corrode.

Cleanroom Manufacturing. Due to the often critical nature of micro medical parts and products, it is often necessary to manufacture under cleanroom conditions. With extremely exacting quality and traceability systems, complete control of the entire manufacturing process is required, and adherence to the parameters set out in ISO 13485 (harmonized with ISO 9001) are hugely important, defining the requirements for a comprehensive quality management system for the design and manufacture of medical devices.

Regulation

The regulatory environment is one that is becoming more and more important for medical device OEMs, and ensuring a partnership with a micromolder that has an understanding of this environment is disproportionately important. Much of the focus today is on the challenging 510(k) approval process, which seemingly changes week to week. In general, FDA has toughened up in the area of product approval and has started to request information from medical device OEMs never previously required. This has meant that the percentage of first-round 510(k) submissions requiring more information has gone up dramatically, with a knock-on effect in terms of time-to-market delays and expense. Engaging a micromolder with an innate understanding of the vagaries of the 510(k) process will save both time and money.

This article was written by Aaron Johnson, Vice President of Customer Strategy at Accumold, Ankeny, IA. For more information, visit here .


Medical Design Briefs Magazine

This article first appeared in the May, 2020 issue of Medical Design Briefs Magazine.

Read more articles from this issue here.

Read more articles from the archives here.