This invention provides a highly conductive
copper paste that cures in an
air atmosphere, its preparation method, and its applications, belonging to the field of
conductive paste preparation technology. The highly conductive
copper paste comprises: 60-80% conductive
copper powder; 3-10%
polymer resin; 1-3% curing agent; 3-10% first
solvent; 1-5% additives; and 7.5-17% particle-free conductive copper ink. The
copper salt precursor in the particle-free conductive copper ink is dissolved in the form of copper ions in a mixture of its complexing agent and second
solvent. When the highly conductive copper paste is heated and cured in an
air atmosphere, the copper ions in the particle-free conductive copper ink are reduced in situ to nano-copper particles, which form welded connections between the conductive copper
powder particles, constituting a conductive network composed of micron-sized conductive copper
powder and in-situ generated nano-copper weld points. The highly conductive copper paste of this invention has low manufacturing cost,
high conductivity, and the potential for
room temperature dormancy and heat-triggered
decomposition.