Polymer thick film solder alloy/metal conductor compositions

A polymer thick film conductor composition comprising:

• (a) 35 to 94 wt % solder alloy powder selected from the group consisting of (i) a tin, silver, and copper alloy powder, (ii) a tin and bismuth alloy powder, and (iii) mixtures thereof, said alloy powder consisting of particles possessing an average particle size of 2 to 18 μm and a surface area/mass ratio in the range of 0.20 to 1.3 m2/g;
• (b) 1 to 30 wt % metal selected from the group consisting of silver, copper, gold, aluminum and mixtures thereof, said metal consisting of particles possessing an average particle size of 2 to 18 μm and a surface area/mass ratio in the range of 0.10 to 2.3 m2/g;
• and
• (c) 5 to 35 wt % organic medium comprising:
• (1) a resin that is a vinyl co-polymer resin of vinylidene chloride and acrylonitrile or a phenoxy resin;
• dissolved in
• (2) organic solvent comprising a dibasic ester or glycol ether;
• with the proviso that if said resin is a phenoxy resin said metal is silver, wherein said solder alloy powder and said metal are dispersed in said organic medium and wherein the wt % are based on the total weight of the polymer thick film conductor composition.