Shoei Chemical Inc.

Mikio Yamazoe

Tetsuya Tanaka

Eiichi Asada

Hiroshi Mashima

Tadashi Kanasaku

Megumi Kawahara

Toshio Inokuma

Tadashi Endo

Nobuko Morinaga

Yuko Koyama

Yoshiko Morinaga

Shigeru Matsumura

A resistor composition containing: a lead-free ruthenium-based electrically conductive component, a lead-free glass having a glass basicity (Po value) of 0.4 to 0.9, and an organic vehicle; wherein, MSiAlOcrystals (M: Ba and/or Sr) are present in a thick film resistor obtained by firing this composition. The ruthenium-based resistor composition is capable of forming a lead-free thick film resistor which eliminates harmful lead components from an electrically conductive component and glass, and has superior TCR characteristics, current noise characteristics, withstand voltage characteristics and stability after a heat cycling test over a wide resistance range.

Resistor composition and thick film resistor

A glass containing no lead and comprising, calculated as oxides: 40-60 wt. % ZnO, 15-35 wt. % BO, 1-16 wt. % SiO, 1-10 wt. % AlO, 2-15 wt. % MnO, and at least one selected from the group consisting of LiO, NaO and KO in their total of 0.5-10 wt. %, and a glass with the above-described components where a total of at least one selected from the group consisting of LiO, NaO and KO is 0-5 wt. %, and at least one selected from the group consisting of MgO, CaO, TiO, CrO, ZrO, TaO, SnO, and FeOis further included in their total of 0.1-5 wt. %. A conductive paste using such a glass as an inorganic binder has a superior binder removal ability and a good sinterability and can form dense conductors with excellent characteristics with respect to resistance to plating solutions, adhesive strength, resistance to thermal shocks, etc.

Glass and conductive paste using the same

A resistor composition comprising at least one electrically conductive powder selected from the group consisting of (a) tin oxide power and (b) powder resulting from heat treatment of tin oxide and tantalum oxide, a glass frit and double oxide of tantalum dispersed in an organic vehicle. In the resistor composition, the mixing amount of the double oxide of tantalum is preferably 30 parts by weight or less with respect to 100 parts by weight of the sum of the electrically conductive powder and the glass frit. The resistor composition provides highly reproducible thick film resistors having superior properties and high stability over a wide range of resistance by addition of the tantalum double oxides.

Resistor composition

A resistor composition comprising conductive particles, a glass frit and a vehicle in which RuO.sub.2 particles coated with a polynary oxide of Bi and/or Pb and Ru are employed and, by using the surface-coated RuO.sub.2, the composition can provide readily a improved resistor having a advantageous combination of properties, particularly a very small absolute TCR and high voltage stability throughout a wide resistance range. The produced resistor can be successfully laser-trimmed without adversely affecting the properties thereof.

Resistor compositions

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Nishitokyo, Japan

Mikio Yamazoe