US 5,474,711 A · Thick film resistor compositions

Abstract

To provide a thick film resistor involving small variations in resistance and TCR during the firing step and a low thermal coefficient of expansion. A thick film resistor composition containing 5-30 wt. % of a ruthenium pyrochlore oxide and 10-90 wt. % of a glass binder, wherein (1) the ruthenium pyrochlore oxide is PbRuO.sub.3, (2) the glass binder is a glass which contains a first glass containing 61-85 wt. % of PbO, 10-36% of SiO.sub.2 and 0-2 wt. % of B.sub.2 O.sub.3, the total content of the PbO, SiO.sub.2 and B.sub.2 O.sub.3 accounting for 95 wt. % or more of the first glass, and in which 2-20 wt. % of B.sub.2 O.sub.3 is contained in the entire glass binder, and (3) the first glass accounts for 5-30 wt. % of the thick film resistor composition, and the weight ratio of the ruthenium pyrochlore oxide to the first glass is 5:30-60:40.

Claims3

Dependent claims

A thick film resistor composition comprising:

(a) 5-30 wt. % lead pyrochlore oxide;
(b) 0-20 wt. % RuO.sub.2 ;
(c) 10-25 wt. % a first glass comprising 61-85% wt. % PbO, 10-36 wt. % SiO.sub.2 and 0-2 wt. % B.sub.2 O.sub.3 ;
(d) 10-40 wt. % a second glass comprising 30-60 wt. % SiO.sub.2, 5-30 wt. % CaO, 1-40 wt.% B.sub.2 O.sub.3, 0-50 wt. % PbO, 0-20 wt. % Al.sub.2 O.sub.3 ;
and
with the proviso that
(i) the total content of PbO, SiO.sub.2, and B.sub.2 O.sub.3 in the first glass comprises at least 95 wt.% of the first glass;
(ii) the total content of PbO, SiO.sub.2, CaO, Al.sub.2 O.sub.3 and B.sub.2 O.sub.3 comprises at least 35 wt. % of the second glass;
(iii) the B.sub.2 O.sub.3 content of the first and second glasses is 2-20 wt. %;
and
(iv) the weight ratio of the lead pyrochlore oxide to the first glass is in the range of 5:30 to 60:40.

8 more elements

Dependencies are inferred from the claim text.

Thick film resistor compositions

Life of this patent

Thick film resistor compositions

Life of this patent

Abstract

Claims3