Abstract: An electric resistor includes a particle continuous body in which a plurality of conductive particles are connected, and a matrix disposed around the particle continuous body. The particle continuous body has surface-joined portions in which surfaces of the conductive particles are joined to each other. Silicon particles are preferably used as the conductive particles. The average boundary line length of the surface-joined portions is preferably 0.5 ?m or more.

Abstract: An electrical resistor includes borosilicate particles, Si-containing particles, and pore parts. The pore parts are constituted by gaps between the borosilicate particles and the Si-containing particles and surround the borosilicate particles and the Si-containing particles. A honeycomb structure includes the electrical resistor. An electric heating catalytic device has the honeycomb structure.

Abstract: An electrically heated catalyst includes a honeycomb substrate, an electrode, and a joining section. The honeycomb substrate and the joining section include matrices and conductive fillers. The matrices contain borosilicate including at least one of an alkali metal and an alkaline earth metal. The joining section preferably has a softening point lower than that of the honeycomb substrate.

Abstract: An electrical resistor comprises a matrix composed of borosilicate containing at least one kind of alkali group atoms selected from the group consisting of Na, Mg, K, Ca, Li, Be, Rb, Sr, Cs, Ba, Fr, and Ra. The electrical resistor preferably has an electroconductive filler. A honeycomb structure comprises the electrical resistor. An electrically heated catalyst device comprises the honeycomb structure. The electrical resistor preferably has an electrical resistivity in a range from 0.0001 to 1 ?·m and an electrical resistance increase rate in a range from 0.01×10?6 to 5.0×10?4/K in a temperature range from 25° C. to 500° C.