Patent ID: 7626320

Claim:
A spark plug comprising: an insulator having a through-hole formed in an axial direction; a terminal attachment disposed on one end side of said insulator; a center electrode disposed on other end side of said insulator; and an electrically conductive connection layer disposed in said through-hole for electrically connecting said terminal attachment and said center electrode to each other, said electrically conductive connection layer including at least one electrically conductive sealing layer connected to at least one of said terminal attachment and said center electrode, wherein said electrically conductive sealing layer is made of electrically conductive glass containing a glass component and a metal component, the metal component being in an amount larger than 30 mass% and smaller than 75 mass% of the electrically conductive glass, and the metal component comprising Cu—Zn alloy in an amount of larger than 10 mass% of the metal component.