With the end of the project approaching, we can summarize the work performed in the following areas.
Producing new materials
In the area of new materials synthesis, the work performed concentrated on up-scaling the production of three new nanomaterials formulations. These were copper nanoparticles for inks and pastes, silver nanowires and graphene nanoplatelets. During the project both the silver nanowires and graphene production was scaled up from lab-scale quantities to commercially available products manufactured at industrial scale. New formulations of the copper nanomaterials were produced to address the demonstrator devices successfully but were not fully scaled.
New manufacturing processes
Along with the new materials, came the requirement to handle them in new ways. In the project a range of new processing techniques were developed. These included laser processing to produce fine scale circuit patterns in all the materials; inkjet printing of the inks and spray coating of the nanowires and graphene. For the copper nanoparticle inks a novel laser sintering process was developed to produce conductive tracks with similar electrical properties of the conventional silver materials.
New demonstrator electronic devices
Using the new processes and materials developed during the project, a range of demonstrator electronic devices were produced to meet the requirements of the end-users of the project and to showcase the technologies. These demonstrators included capacitive touch screens using printed copper electrical connections or silver nanowire conductive coatings, LCD signage devices with silver nanowire transparent screens, and solar cells with low-cost printed copper electrodes.
Pilot production equipment
In order to produce real working devices, using the new materials and processes, there is also a requirement to demonstrate industrial scale equipment on which to use them. The key part of the machine concept was to facilitate manufacturing printed electronics devices on arbitrarily-sized substrates up to “Gen 5” (1.3 m x 1.1 m) to address the requirements of all the project partners and for tackling real-world scale samples e.g. full-scale solar cell panels. This pilot system, with inkjet printing laser pattering and sintering capabilities was built successfully and is in full operation at M-Solv. In addition to this large system, the project also produced two other pilot production machines for the end users: A silver nanowire and graphene spray coating system was produced and tested and a novel laser system to sinter the copper electrodes on solar cells, which was installed at one of the end-user’s sites.
Nanosafety
There are many known hazards of nanomaterials, and these may increase as the production volume is scaled-up, and these should be considered if there are plans to use a nanomaterial in a commercial capacity. INSPIRED brought together various partners in different sectors of the nanotechnology industry to help with studying the safety of nanomaterials throughout different scale-up processes. In this context, the INSPIRED project developed a wide range of guidelines and a Best Practice Guide to support the safe handling and use of conductive nanomaterials for printed electronics applications, considering integrated strategies to control the exposure to nanoparticles in industrial settings, and provide the end-users with appropriate knowledge to minimise and control the nanoparticles released.
