E.i. Dupont De Nemours and Company

Jacob Hormadaly

Howard W Jacobson

Thomas Paul Feist

Oswald Robert Bergmann

Barry E Taylor

A product and process are disclosed that relate to electroconductive powders based on tantalum, niobium, or phosphorus or any combination thereof doped tin oxide and coatings containing such powders. These powders can be used for making transparent coated films that are conductive and have desirable properties for a number of end uses. Some important end uses are in static dissipative fiber and films, coatings for recyclable containers, materials involved in packaging, where the presence of certain heavy metals is undesirable, transparent conductive coatings, among other uses.

Tin oxide based conductive powders and coatings

A product and process are disclosed that relate to electroconductive powders based on tantalum niobium, or phosphorus or any combination thereof doped tin oxide and coatings containing such powders. These powders can be used for making transparent coated films that are conductive and have desirable properties for a number of end uses. Some important end uses are in static dissipative fiber and films, coatings for recyclable containers, materials involved in packaging, where the presence of certain heavy metals is undesirable, transparent conductive coatings, among other uses.

The invention is directed to a thick film paste composition comprising electrically conductive particles and finely divided particles of a glass composition comprising by mole % 5-70% Bi.sub.2 O.sub.3, 18-35% SiO.sub.2, 0.1-40% CuO, 0.5-25% ZnO, 0.5-40% CoO, 0.5-40% Fe.sub.2 O.sub.3, and 0.5-40% MnO, which the glass composition is free of lead and cadmium, all dispersed in an organic medium.

Cadmium-free and lead-free thick film conductor composition

A crystallizable glass composition comprising PbO and/or Bi.sub.2 O.sub.3, ZnO, B.sub.2 O.sub.3, Cr.sub.2 O.sub.3, SnO.sub.2 and optionally SiO.sub.2 and/or Al.sub.2 O.sub.3, having an optical density parameter .gtoreq.1.6.

Encapsulant composition

Thick film thermistor paste comprising an admixture of finely divided particles consisting essentially of a) a conductive phase consisting of (1) at least one oxide of a platinum group metal having a positive TCR, and (2) Co.sub.2 RuO.sub.4, b) an inorganic binder having a Dilatometer softening point of 450.degree.-750.degree. C. which contains transition metal oxides and is free of alkali metal oxides, c) a filler selected from vitreous silica, zircon and mixtures thereof, all of (a) through (c) being dispersed in, d) an organic medium.

Thick film NTC thermistor compositions

A crystallizable glass composition comprising ZnO, PbO, B.sub.2 O.sub.3, SiO.sub.2, SnO.sub.2 and optionally Al.sub.2 O.sub.3 and/or Cr.sub.2 O.sub.3.

The invention is directed to a thick film thermistor composition consisting of finely divided particles of (a) a ruthenium-based pyrochlore, and (b) a short borosilicate glass or glass mixture, both dispersed in (c) an organic medium.

Thermistor composition

The invention is directed primarily to a method of doping tin oxide with Ta.sub.2 O.sub.5 and/or Nb.sub.2 O.sub.5 using pyrochlore-related compounds derived from the system SnO--SnO.sub.2 --Ta.sub.2 O.sub.5 --Nb.sub.2 O.sub.5 for use in thick film resistor compositions. The invention is also directed to thick film resistors containing the above-described pyrochlore-related compounds and to various compositions and methods for making such thick film resistors.

Method for doping tin oxide

The invention is directed to a thick film resistor composition comprising a dispersion in organic medium of an admixture of finely divided particles if (a) SnO, SnO.sub.2, Ta.sub.2 O.sub.5 pyrochlore, (b) a specifically described borosilicate glass containing NiO and (c) copper oxide either adsorbed on the solids or in the form of finely divided particles admixed therewith.

Resistor compositions

The invention is directed primarily to a method of doping tin oxide with Ta.sub.2 O.sub.5 and/or Nb.sub.2 O.sub.5 using pyrochlore-related compounds derived from the system SnO-SnO.sub.2 -Ta.sub.2 O.sub.5 -Nb.sub.2 O.sub.5 for use in thick film resistor compositions. The invention is also directed to thick film resistors containing the above-described pyrochlore-related compounds and to various compositions and methods for making such thick film resistors.

Thick film resistor composition which is a dispersion of (a) a conductive phase of a nonprecious metal pyrochlore and SnO.sub.2, (b) inorganic binder and (c) CoCrO.sub.4 and/or NiCrO.sub.4 in (d) organic medium. The metal chromate functions as a TCR driver.

Resistor composition comprising an admixture of finely divided particles of (a) ruthenium-based conductive material, (b) inorganic binder and (c) cobalt ruthenate.

Growing community of inventors

Wilmington, DE, United States of America

Jacob Hormadaly