The New U.S. Evaporative Emission Regulations, which set forth the level of hydrocarbon evaporation generated from vehicles, have been applied in the industry since 1994. In order to meet the Regulations, the filler hose is required to be made for a one tenth of the gasoline permeability of that for conventional filler hose, without design change. The fuel filler hose must also provide a flexible configuration, such as a bellowed or a complicatedly curved shape
In order to cope with the problems above, the Author, et al, have successfully developed A LOW PERMEATION FUEL FILLER HOSE which has a high freedom of configuration.
During the first stage of development, the Author, et al, developed a hose of 2-layer structure using FKM rubber for inner layer as the permeation barrier, which is applicable in the bellow shape, by means of a unique molding technique.
During the second stage of development, the inner wall of the rubber hose was changed to a thin resin film as the permeation barrier layer, instead of using expensive FKM rubber, which can be formed in a bellow shape to reduce the cost.