The automotive supplier was initially looking for a thermal management material to fill and dissipate the air gaps between the PCB and cooling channels in its onboard chargers. They believe they need a material with a thermal conductivity of 4-6W/m.K. After further discussions to understand the application in more detail, Electrolube determined that this automotive customer experienced hot spots on the PCB when thermal management materials were used. This is due to the high viscosity of these products and the very small gaps in the on-board charger for the material to flow, which leaves the material with air bubbles after filling. Air is a poor conductor of heat, about 0.025W/m.K, so remaining air bubbles reduce the efficiency of heat transfer.

Electrolube suggested researching a thermally conductive resin with a lower viscosity and better flow to more efficiently fill the smallest voids in devices. Additionally, customers required high dielectric strength, excellent protection from automotive fluids, and support for vibration, while also providing flexibility for fragile components during thermal shock. These special requirements have prompted Electrolube to develop the versatile UR5608 polyurethane resin, which provides good flow even in small pitches (~0.5mm) and mixes well with other materials and holds up well its flexibility. UR5608 has a dielectric strength of 18kV/mm and passed UL94
V-0 certified. Although the thermal conductivity of this resin is 0.78W/m.K lower than the original specification, the low viscosity UR5608 has proven very successful in eliminating any air gaps in the material, which greatly reduces thermal resistance.

UR5608 was tested by automotive customers, with whom Elegor achieved the most efficient production process, recommending gentle heating of the material and potting at a very small angle to further improve flow and remove all air bubbles from out of the device. During testing, the UR5608 flowed well in the customer’s unit, and they achieved the desired heat dissipation. The UR5608 was subsequently approved for this application after demonstrating effective heat transfer between certain thermal components, inductors and capacitors and liquid cooling channels within the aluminum metal enclosure.

Bethan, Global Product Manager, Encapsulation Resins, Electrolube, a MacDermid Alpha Electronic Solutions Company
Massey commented: “Our automotive customers are very satisfied with the solutions we provide, and we believe our problem-solving skills and commitment to delivering innovative and reliable solutions will ultimately ensure our continued success as a leading supplier of electrochemical products to the automotive industry. status.”

“MacDermid Alpha electronic solutions are available through our Alpha, Compugraphics, Electrolube, Kester and MacDermid
Innovative specialty chemicals and materials from brands like Enthone enable the interconnection of electronics. We serve all regions of the world and at every step of the electronics supply chain for all steps of device manufacturing. Experts in our Semiconductor Solutions, Circuit Solutions and Assembly Solutions divisions work with OEMs and fabricators to implement new technologies that redefine what is possible in device design. Our world-class technical services are always on hand to ensure optimal results for yield and productivity. Our solutions increase yield, reduce carbon footprint, lower total cost of ownership, and enable electronic innovation. “