The material of the electrode on the ceramic side consists mainly of silver. This
silver electrode is made by printing silver in the form of a paste on both sides of the ceramic. It is
then baked at high temperature to complete the electrode.
When the bond between the silver electrode and the ceramic becomes strong, the
ceramic no longer expands or contracts easily, and the electrical characteristics deteriorate (the sound
pressure falls). Conversely, if the adhesive strength is weak, the ceramic will readily expand and
contract, and the electrical characteristics will improve (the sound pressure will increase).
In this way, he adhesive strength of the silver electrode has an inverse relation to
the electrical characteristics. Because the product is designed to ensure that both the adhesive
strength and electrical characteristics are optimum, a limit is imposed on the adhesive strength.