Tank joint parts

Abstract

A tank joint part welded to the resinous outer surface of a fuel tank is formed of a resinous material such that the difference in volume swelling between materials of the tank joint part and the outer surface of the tank is 10% or less when they swell with fuel, and that the bonding strength therebetween is at least 2 MPa. The tank joint part may be comprised of a main member and a joining member if every two adjoining materials satisfy the above requirements. The main and joining members are preferably formed by two-color injection molding. The tank joint part maintains good fuel impermeability and bonding strength even after exposure to fuel.

Dependencies are inferred from the claim text.