Lead-free thick film paste composition
AssigneeE. I. Du Pont de Nemours and Company
InventorsAlan F. Carroll, Kenneth W. Hang
Life of this patent
Estimating the term…
Abstract
A screen-printable thick film paste composition suitable for forming conductive patterns on a rigid substrate comprising: (a) finely divided particles of a lead-free glass composition having a softening point log (eta)=7.6 poise from 400.degree. C.-650.degree. C., a log (eta.) specific viscosity in a range from 2 at 500.degree. C. to 5 at 700.degree. C. and consisting essentially of, by weight 65-95% Bi.sub.2 O.sub.3, 2-15% SiO.sub.2, 0.1-9% B.sub.2 O.sub.3, 0-5% Al.sub.2 O.sub.3, 0-5% CaO, and 0-20% ZnO; and (b) electrically conductive particles; and all of (a) and (b) being dispersed in (c) an organic medium.
Claims9
A screen-printable thick film paste composition suitable for forming conductive patterns on a rigid substrate comprising:
- (a) finely divided particles of a lead-free glass composition having a softening point log (eta)=7.6 poise from 400.degree. C.-650.degree. C., a log (eta) specific viscosity in a range from 2 at 500.degree. C. to 5 at 700.degree. C. and consisting essentially of, by weight 65-95% Bi.sub.2 O.sub.3, 2-15% SiO.sub.2, 0.1-9% B.sub.2 O.sub.3, 0-5% Al.sub.2 O.sub.3, 0-5% CaO, and 0-20% ZnO;
- (b) electrically conductive particles;
- and
- all of (a) and (b) being dispersed in (c) an organic medium.
Dependencies are inferred from the claim text.