US Patent 7562679 Resin pipe and resin molded component

A filler pipe, wherein a flow path for a fluid is formed through multiple resin materials being extruded simultaneously and wherein a corrugated part is shaped through peaks and valleys disposed continuously, comprises an outer layer formed from a high density polyethylene, a barrier layer formed from EVOH with superior resistance to fuel permeation, and an inner layer, formed from high density polyethylene. The structure is such that d<L when the depth from the apex of the peak to the bottom of the valley is defined as d, and the distance from the apex of the peak to the barrier layer is defined as L.