U.S. Coal to Conductive Inks

The overall objective of the project is to develop a process for the manufacture of conductive inks using U.S. coal as a primary feedstock. Minus 100 LLC, in collaboration with existing graphite manufacturers and ink formulators, will develop new or improved methods of manufacturing conductive ink products using coal as a primary feedstock. There are existing commercial markets for conductive inks ($2.3 billion in 2015) and the expected growth of these markets is significant (projected growth to $3.9 billion in 2021). The growth will primarily occur in existing and advanced printing methods to be used for electronic circuits, heating elements, Radio Frequency Identification (RIFD) tags, photovoltaic components, electronic displays, 3D printing and fluid/plastic materials used to enhance the electrical/thermal/optical properties of the final printed material. A significant portion of the current conductive inks use elemental silver or silver compounds as a means of achieving high levels of conductivity. This expensive base material will be replaced with electrically conducting coal-based materials that are significantly lower in cost. It is estimated that the unit cost of these coal-based materials will be a least 50% less than silver-based conductive inks, thus providing a significant advantage to penetrate these markets. The current conductive ink applications have requirements of electrical resistivity ranging from (< 1 ohm/square) to about (100,000 ohm/square). An example of a higher resistivity application is in the fabrication of automobile windshield heating assemblies that require a cured ink with a higher resistivity to allow heating of the printed electrical filaments. Because the ink markets are very fragmented, Minus 100 LLC will collaborate with existing ink formulators to develop the final ink formulations and to package/distribute the final products for specific targeted applications. The highly conductive inks to be developed will use graphite or combinations of graphite and graphene as the primary component of the conductive ink particles. The commercial manufacturing of graphene is in its infancy and currently top-down, scalable manufacturing processes use graphite as a precursor material. Minus 100 will collaborate with existing graphite manufacturers to convert domestic coal sources to graphite/graphene platelets that, in turn, can be used to produce highly conductive inks. During Phase I, Minus 100 will develop the coal-based processes, pigments and pastes to be used for the manufacture of a variety of conductive inks from a selected coal-based feedstock. Preliminary work at laboratory scale has verified the basic technical approaches to be used. Process flow diagrams will be developed for the individual process steps with the aim of a practical scale-up to commercial or demonstration scale operations. A bottoms-up cost analysis will be performed to validate the economics of the new/improved manufacturing process using coal as the primary feedstock. During Phase II, a pilot scale assembly for critical process operations will be fabricated, and the procedures, compositions and formulations used for conductive ink manufacturing from coal-based feedstocks will be enhanced and improved upon. The manufacturing cost estimates developed under Phase I will be updated.