Showa Denko (SDK) has developed an innovative technology that directly connects / bonds aluminum alloys and polycarbonate resins without the need for adhesives throughout the process.
Usually aluminum alloy and polycarbonate resin are connected / bonded by mechanical connection (using bolts, etc.) or adhesive (using adhesive). In recent years, attention has been focused on new technologies for directly connecting / bonding metallic materials during injection molding of resin materials. These new technologies have the potential to streamline processes, increase productivity, and process into complex shapes. In many cases, however, they rely on mechanical adhesion, such as anchoring effects caused by the injection of resin into rough metal surfaces. Therefore, polycarbonate resins (and other amorphous engineering plastics) are generally considered unsuitable for joining / bonding metallic materials by conventional methods.
SDK enables this direct connection / adhesion with its years of expertise in aluminum alloy and polymer chemistry. Specifically, the SDK has developed an innovative joining / bonding technology based on special surface treatments and primer treatments for aluminum alloys. In addition to the anchoring effect, this technology also achieves chemical bonding capabilities. Experiments have shown that the new technology can be used under conventional polycarbonate molding conditions, providing reliable bond strengths in excess of 25 MPa. No special conditions or equipment are required while ensuring sufficient adhesive strength.
This technology can directly bond / bond commercial polycarbonate resins and lightweight aluminum, making it suitable for smartphone cases. SDK will continue to develop and optimize its aluminum surface treatment technology and primer coating conditions to improve bond strength and durability. In the future, the SDK will focus on the use of super heat-resistant super engineering plastic technology in automotive parts applications.
In the SDK's mid-term business plan "TOP 2021", the SDK is promoting cooperation between various business units and strengthening marketing. The automotive and electronics industries have increasing demands for a variety of complex materials. These materials are light and have better heat dissipation, heat storage and insulation properties. Given this market demand, the SDK is working to develop composite materials by combining its own diverse technologies. The metal / resin direct connection / adhesion technology announced this time is an example of this effort.