Solder paste is not a commodity, and it is important to understand why.
Solder paste is likely the most complex material used in any manufacturing process. I think most people know that solder paste is a combination of solder powder and flux; at first blush it seems quite simple. However, even the solder powder is not a commodity. In superior solder paste, the powder size distribution and the alloy chemistry are both precisely controlled, the solder particles are spherical, and oxidation levels are minimized.