This invention provides a thick-film type dielectric with desired adhesivity to the base and very good insulation properties. The dielectric of the present invention includes a lower dielectric layer made of a photosensitive composition and an upper dielectric layer which is made of a photosensitive composition and formed on the aforementioned lower dielectric layer. The softening point (T1) of the primary glass powder used for the aforementioned lower dielectric layer, the softening point (T2) of the primary glass powder used for the aforementioned upper dielectric layer, and the firing temperature (T3) of the aforementioned primary glass powder satisfy the following relationship: T1