Flexible printed electronics is an emerging electronic technology for making organic/inorganic materials electronic devices on flexible/ductile plastic or thin metal substrates. The materials used in the flexible printed electronics are mainly functional inks and substrates. Functional inks are inorganic, organic, and nano-functional materials, through specific formulations and dispersing means to form solutions or suspensions and achieve the specified physical and chemical performances, such as, dispersibility, viscosity, surface tension and solid content to adapt to the printing or coating process requirements. Generally flexible printed electronics base materials can be divided into two categories, including rigid base materials and flexible base materials. The rigid base materials mainly refer to the metal base materials, such as rigid copper clad plate, ceramic type base plate, glass base plate and so on and the flexible base materials include paper, fiber fabric, plastic film, metal foil and so on. Base material selection is mainly based on the product design and the base material should support the production process. Besides, the common flexible printed electronics includes carbon nanotubes, graphene, organic conductive materials, nanocrystalline silicon, metal oxide semiconductors, organic semiconductor materials, organic light-emitting materials and so on. This technology has the advantages of simple production process, small raw material loss, less investment in equipment, large area, light, flexible, low-cost production and green initiative, which has very broad development prospects.
Bio-pharmaceutical: As a tool to diagnose or monitor human life signals, flexible printed electronics can be used to collect health data, monitor diseases and rehabilitation of patients. For example, we can implant micro-flexible temperature sensor in biomedicine to detect abnormal cells and assist treatment. In addition, there is growing reliance on implantable medical devices such as implantable pacemakers and implantable atrial defibrillators in the treatment of various cardiovascular and neurological diseases.
Wearable electronic products: We can continuously monitor our physical condition anytime, anywhere through wearable electronic medical devices. For example, in sports and fitness industry, flexible wearable electronics can be used to monitor and alert the user's fitness data, and to achieve a reasonable amount of functions such as exercise reminders, exercise statistics and movement data analysis and so on.
Aerospace: The development of flexible printed electronics applications in the aerospace field requires more stringent precision and emphasizes the accuracy of data acquisition. For example, flexible printed electronics can be wrapped on the surface of wings for monitoring and transmission of the aircraft health information.
Communications & entertainment: This kind of product mainly satisfies the users' demands for information communication and entertainment, such as the flexible circuit contact lenses and flexible display phones.
1. Lu ZH, et al. (2014). New progress in flexible wearable electronics. Technology Forum.