Patent ID: 7326370

Claim:
A black conductive composition comprising, based on the total composition weight percent: 3-50 weight percent of conductive metal oxide particles selected from RuO 2 , ruthenium polyoxide, and mixtures thereof; 25-85 weight percent organic matter comprising organic polymer binder selected from the group consisting of copolymers and interpolymers made from (1) non-acidic comonomers selected from the group consisting of C 1-10 alkyl acrylates, C 1-10 alkyl methacrylates, styrene, substituted styrene, and combinations thereof, and (2) acidic comonomers and acid comonomers including an ethylenically unsaturated carboxylic acid, said organic polymer binder being at least 15 wt % of the total polymer weight; and organic solvent; and 5-70 weight percent of one or more lead-free bismuth glass binders wherein said glass binder comprises, based on weight percent total glass binder composition: 55-85% Bi 2 O 3 , 0-20% SiO 2 , 0-5% Al 2 O 3 , 2-20% B 2 O 3 , 0-20% ZnO, 0-15% of one or more of oxides selected from BaO, CaO, and SrO; and 0-3% of one or more of oxides selected from Na 2 O, K 2 O, Cs 2 O, Li 2 O and mixtures thereof; and wherein the softening point of said glass binder is in the range 400-600° C.; and wherein the surface area to weight ratio of said conductive metal oxide particles are in the range of 2 to 20 m 2 /g; and wherein said composition is characterized by being lead-free.