The markets: Electronics (2019)

Glass fiber/epoxy laminates have been the foundational structural substrate in printed circuit boards (PCBs) for decades. These iconic thin, green “cards” support the transistors, resistors and integrated circuits at the heart of almost all digital technologies and connect them electrically via conductive pathways etched or printed on their surfaces. Multilayer PCBs are made by interleaving copper clad (and etched) laminates with high resin content (HRC) prepreg layers and then compressing into an integrated structure. Holes are then drilled and plated with copper to create vias connecting the etched circuits within. The cores serve as the structural units while the HRC prepreg provides dielectric insulation between adjacent layers of copper circuits.

According to industry sources, the global PCB market was valued at US$63.1 billion in 2017 and is expected to reach US$76.9 billion by 2024, at a compound annual growth rate (CAGR) of 3.1%. Market growth factors for the PCB market include increased adoption of automation in various end-user industries, increased demand for wireless devices, increasing miniaturization of devices, the need for increased efficiency of interconnect solutions and increased demand for flexible circuits.

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Glass/epoxy’s dominance, however, has been under challenge as many of these trends — notably, toward miniaturization, better thermal management, increased speed and performance, and 3D printing — force PCB manufacturers to re-examine their material options. And circuit boards aren’t the only components where new materials are being used.

For example, Samsung’s (Seoul, South Korea) new Galaxy Note9, which launched in 2018, employs a Water Carbon Cooling system, which is said to allow the phone to run smoothly during heavy use. According to Samsung, the cooling system uses a heat pipe, or “thermal spreader,” to use changes in the phases of water to efficiently radiate heat. First, a porous structure filled with water absorbs the heat, then the water is turned into steam and moved through pipes. The steam then begins to cool and turns back into water and the process begins again, dispelling more heat with each subsequent cycle. The Galaxy Note9 has a larger heat pipe than its predecessor and also benefits from an enhanced carbon fiber TIM (thermal interface material) that is said to transfer heat from the processor to the thermal spreader with 3.5 times greater efficiency, boosting thermal conductivity and helping to prevent overheating.

At the time of this writing, there were reports that Honor’s upcoming Honor Magic 2 phone could feature graphene batteries. The graphene technology is expected to assist in dissipating heat and also increase the life of the battery.

DuPont Electronics & Imaging (Wilmington, DE, US) is launching its second generation of In-Mold Electronic (IME) materials. IME technology enables functions such as touch controls and lighting to be directly embedded inside of plastic parts by printing circuits onto plastic sheets, which are then thermoformed and injection molded. This is said to allow product engineers to reduce weight and cost while increasing design aesthetics and functionality in everything from car dashboards to home appliances, using fewer parts and manufacturing steps. Second generation advancements in the technology include a new electrically conductive adhesive that is more flexible than epoxy-based systems, a protection encapsulant for use as tie-coat and top seal, and crossover dielectric that reduces the number of layers required.