A kind of highly thixotropic conductive silver paste

Abstract

The invention discloses a high-thixotropy conductive silver paste. The high-thixotropy conductive silver paste is prepared according to the following method. The method comprises the following steps: mixing 20 to 30 percent of matrix resin, 3 to 5 percent of a curing agent, 0.1 to 0.3 percent of an accelerant, 0.3 to 0.5 percent of a coupling agent, 3 to 4 percent of a thinning agent and 0.01 to 0.03 percent of a defoaming agent, adding 60 to 70 percent of metallic silver powder and 0.5 to 1.5 percent of a thixotropic addition agent into the mixture after the mixture is ground, and continuing to grind the mixture until the mixture is uniform after uniform stirring. The silver paste disclosed by the invention is high in thixotropy and levelling property and poor in printability, so that the quality and production efficiency of electronic packaging products can be improved greatly.

Description

Technical field [0001] The invention belongs to the field of metals and electronic materials, and relates to a highly thixotropic conductive silver paste and a preparation method thereof. Background technique [0002] Conductive silver paste is a key functional material required by the electronic components, integrated circuits and solar cell industries, with huge market demand and great potential for technological progress. In the current electronic paste field, silver paste has the characteristics of high conductivity, stable performance, and high bonding strength with the substrate, and is widely used in the production of electronic components such as integrated circuits, multi-chip components, and membrane switches. [0003] The thixotropy of conductive silver paste has a great influence on the yield of circuit printing, such as viscosity, adhesion, adhesion, leveling, film formation, solvent volatility, etc., will affect the printing performance of the circuit, resulting in T...

AI Technical Summary

Problems solved by technology

[0003] The thixotropy of conductive silver paste has a great influence on the yield of circuit printing, such as viscosity, cohesiveness, adhesion, leveling, film forming, and volatility of solvents, etc. will all affect the printing performance of the circuit, resulting in The phenomenon that the conductive circuit falls off from the substrate makes the conductive circuit scrapped, so the thixotropy of the conductive silver paste needs to be improved

[0004] Although there are many rheological additives that can improve the thixotropic properties of the product at this stage, each rheological additive has some limitations. For example, organic bentonite and fumed silica will affect the gloss of the slurry, and hydrogenated castor oil is susceptible to temperature. Influence, the moisture resistance of polyurea compound is poor, and the viscosity of polyethylene wax is small, so none of the above methods have achieved ideal results