Engineering thermoplastics are used throughout the consumer electronics (CE) industry today because they enable design freedom while also providing high performance capabilities. Although the industries differ, with CE having fewer regulations and being faster to market as an example, many of these existing materials can provide excellent solutions to medical device designers and manufacturers who are challenged to continue bringing new and innovative ideas to the healthcare industry. This article focuses on the features and benefits of high-performance plastics used in consumer electronic devices and their translatability to the healthcare industry to help address similar trends and needs in medical devices and equipment.

Fig. 1 – Greater access to mobile communications and the advancements of material technologies are helping to power the growth of the mobile healthcare segment, which includes devices that are lightweight, portable, easy to operate, and capable of data acquisition and transmission.
The increased availability of improved healthcare has been a contributing factor to longer life expectancies globally, which in turn has led to a rising population growth. According to the Population Reference Bureau (www.prb.org/wpds/2015 ), the population estimate for 2050 is 9.8 billion, a 34 percent increase (2.5 billion) from the 2015 population estimate of 7.3 billion. Between 2015 and 2050, the proportion of the world’s population over 60 years will nearly double from about 12 percent to 22 percent, as reported by the World Health Organization (WHO) (www.who.int/mediacentre/factsheets/fs404/en ). The continual rise in population, especially of the elderly, puts a strain on the existing healthcare infrastructure particularly with challenges in accessibility to hospitals and doctors. As a result, the demand for cost-saving advanced medical technologies that are available remotely, where the need for care exists, continues to grow—from local clinics, to workplace infirmaries, to homes.

At the same time, urbanization and a growing middle class have changed the healthcare landscape, making medical care more affordable and available. According to the United Nations Department of Economic and Social Affairs (UN DESA) (www.un.org/development/desa/en/news/population/world-urbanization-prospects.html ), by 2050, 66 percent of the world’s population will live in cities. A higher socioeconomic status has enabled greater access to mobile communication technologies, leading to the adoption and use of smart devices in our everyday lives—from financial transactions to home security monitoring. This trend has driven higher expectations for convenience and flexibility in medical services and has resulted in a growing mobile health segment, which includes equipment for selftesting and self-monitoring that is lightweight, portable, easy to operate, and capable of data acquisition and transmission. (See Figure 1)

Consumers Have Similar Device Requirements

These trends have led medical device manufacturers, which typically sell to hospitals and physicians, to a new set of customers for remote and mobile healthcare who need to be satisfied. The consumers who are buying portable electronic devices, such as mobile phones, GPS systems, tablet and ultranotebook PCs, are also medical patients in need of portable healthcare equipment options. The good news is that many of the device requirements are common to both industries.

Figure 2 – Polycarbonate-based compounds reinforced with specialty formulated additives and fillers enable antenna circuitry to be integrated with the device housing. This feature enables a device that requires connectivity to be smaller and can also eliminate secondary processes, which can help customers reduce assembly time and cost. (Credit: LPKF AG)
Consumer demand is driving the rapid global growth of handheld and portable devices, for both electronics and healthcare. The quest for the next lighter, thinner, stronger, sleeker, smarter electronic gadget is similar to the requirements placed on portable medical devices— from today’s insulin pumps and blood glucose monitors to tomorrow’s portable hemodialysis equipment.

Medical device designers and manufacturers seek high-performance materials that are light in weight and can provide strength, durability, and aesthetics for their equipment. Additionally, they search for materials that can provide necessary functionality including flame retardancy, weatherability, and data connectivity.

With the overlap of common customer requirements between industries, there are many opportunities to share design and technology innovations. Insights gained from the more mature, but ever-evolving consumer electronics industry, have significant potential for transfer to the emerging remote and mobile healthcare segments.

Design Flexibility for Miniaturization

Handheld or portable devices must be small, lightweight, and provide hightech functionality. A sophisticated process called laser direct structuring (LDS) has enabled design flexibility and helped drive productivity, through part consolidation and miniaturization.

Fig. 3 – High-performance engineering thermoplastics enable thin, small electronic devices that must also be strong, stiff, and impact resistant. In addition to offering a variety of rich color options, polycarbonate siloxane copolymers provide low temperature ductility, chemical resistance, and improved processability.
LDS was developed in 1997 by LPKF Laser and Electronics AG, Garbsen, Germany, and is used to integrate electronic and mechanical functions into a single component. Polycarbonatebased compounds reinforced with specialty formulated additives and fillers can be used with the LDS process to integrate electronics and mechanical materials, like an antenna, into a device framework.

Incorporating LDS into a design can enable the consolidation of components, help achieve miniaturization, and reduce secondary operations such as metal stamping, all of which can result in cost and weight savings. The technology also enables accelerated design changes, which is advantageous in the electronics area where consumers are rapidly demanding the latest and greatest device features. (See Figure 2)

This solution, which also meets the demand for thinner, lighter weight technology, has been used for smartphones and can also be considered for mobile health devices, which utilize wireless technology to communicate diagnostic information to doctors and medical centers, including devices for monitoring heart rate, pulse, oxygen level, and blood pressure.

Thin, Light, and Strong for Portability

Advancing medical technologies, and the demand for portability, have led to more devices being built with microprocessors and electronic circuits to control their functions. The miniaturization of electronics, as well as advanced technologies for housing materials, have enabled devices to become increasingly more compact and lightweight, while allowing them to maintain strength, durability, and performance in a number of environments.

Polycarbonate siloxane copolymer materials, often used in consumer electronic device housings, can provide superior impact resistance and improved processability over other conventional materials. The low-temperature ductility of the silicone gives the material its outstanding impact performance. Because siloxane is relatively unaffected by heat or humidity under typical aging conditions, these materials retain their properties for a longer time than standard polycarbonate resins. (See Figure 3)

Superior flow is a critical material processing feature that enables thinner walls and contributes to lighter weight, without sacrificing impact and ductility. Using a high-flow ductile polycarbonate allows an injection mold to fill completely, enabling the fine details needed for decoration or functionality that have become requirements for small devices such as insulin pens, glucometers, and cardiac monitors.

Several industries are pushing innovation in miniaturized designs for electronic devices—healthcare among them. Addressing this trend requires ultra-thin housings using materials that can offer heat- and flame-resistance to manage high-temperature internal electrical components, for example, in portable computing battery covers and game console enclosures. Engineering thermoplastic materials are able to provide robust thin gauge flame retardancy, with certain polycarbonate blends able to meet UL 94 V0 at 0.5mm and V2 at 0.4mm thickness. A range of flow and ductility performances are also available, based on application requirements. These materials also pass stringent high-temperature and humidity aging tests to ensure long-term reliability of a device.

Chemical Resistance to Maintain Functionality and Appearance

High touch surfaces on any device—from gaming controllers to inhalers—can be exposed to a number of chemicals found in commonly used products such as lotions, sunscreens, and hand creams. The materials used in the equipment surfaces that come into contact with these substances must provide the chemical resistance needed to avoid cracking and other surface impairments.

With increasing numbers of wearable monitors being introduced into the healthcare market to track activity levels, sleep patterns, or heart rhythms, the resistance to everyday chemicals becomes a critical material requirement for the device housing to maintain its functionality and appearance. Polycarbonate/polybutylene terephthalate (PC/PBT) resins are frequently selected for use in consumer electronic device housings and frames because, in addition to providing very good chemical resistance compared to PC/ABS blends, they can offer a non-brominated, non-chlorinated, flame-retardant solution that meets UL94 V0 at 1.5mm. These colorable materials also provide good flow, impact, ductility, and dimensional stability.

High touch surfaces can also be a breeding ground for germs and are, therefore, subject to more frequent cleaning. Materials that can withstand aggressive cleansers and disinfectants become a critical factor in device design and manufacture, for both consumer electronic devices and medical devices. Within the healthcare industry, the repeated wipe down of medical equipment to help prevent the spread of infections can put devices at risk for substantial wear and tear, known as environmental stress cracking (ESC). PBT resins can offer even greater chemical resistance than PC/PBT blends and have shown compatibility with various disinfectants, including bleach and alcohol-based chemicals.

Aesthetics to Differentiate Design

Style and appearance are important considerations in the purchase of electronic devices. The availability of an extensive array of designs, colors, and textures in mobile phones is a great example of the demand for options to reflect consumer individuality. Aesthetics can be equally important to the patient consumers of drug delivery and monitoring devices, which are often required to be used in public settings. In addition, patients who administer healthcare within their home, such as with CPAP machines to address sleep apnea, desire equipment that is sleek and blends in with the décor of the home versus having the appearance of bulky hospital equipment.

Aesthetics can also be a differentiator for device designers and manufacturers. Rich jewel tones, metallic offerings, and textures achieved with a range of engineering thermoplastics can eliminate secondary processes, such as painting and coating, and can expand device appeal without compromising on impact resistance, low temperature ductility, and chemical resistance. Polycarbonate siloxane copolymers can be used to help improve processability over other polycarbonate resins, helping to reduce customers’ processing cycle times and increase manufacturing efficiencies, which can ultimately lead to lower production costs.

In-mold decorating with PC and PC blends is an efficient and cost-effective process used to enable new design options. Using a single operation and eliminating secondary processes, including painting and coating, highquality and long-lasting graphics can be created for electronic device components. PC films offer a range of chemical and abrasion resistance and can also provide high gloss, light transmission, and increased surface hardness depending on the device requirements.

Devices that are designed to be both attractive and easy to use are especially relevant to the healthcare industry—and can positively impact patient compliance.

Conclusion

Engineering thermoplastics used throughout the consumer electronics industry today provide excellent solutions to medical device designers and manufacturers because they enable design freedom while also providing high performance capabilities like impact resistance, chemical resistance, and flame retardancy.

As sophisticated patient consumer influence continues to grow in healthcare, the demand for sleek, high performance, easy to use equipment and devices will become stronger.

Although the healthcare industry is more regulated, sharing proven technologies and material solutions across industries can quickly turn insights into cost-competitive solutions enabling faster times to market.

This article was written by Cathleen Hess, Director of Healthcare Marketing for the Innovative Plastics Business of SABIC, Pittsfield, MA. For more information, Click Here .


Medical Design Briefs Magazine

This article first appeared in the December, 2015 issue of Medical Design Briefs Magazine.

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