An elongated multi-layer tubing is disclosed for connection to a motor vehicle
system to handle fluids containing hydrocarbons. The tubing includes a first layer
disposed radially innermost and having an inner surface capable of prolonged exposure
to a fluid containing hydrocarbons and an outer surface spaced a first predetermined
radial thickness from the inner surface, the first layer consisting essentially
of an extrudable, melt-processible thermoplastic. The tubing also includes a second
layer having a second predetermined radial thickness at most equal to the thickness
of the first layer. The second layer is uniformly and homogeneously connected to
or bonded to the first layer and consists essentially of an extrudable, melt-processible
thermoplastic capable of sufficiently permanent laminar adhesion with the first
layer to prevent delamination during a desired lifetime of the tubing. At least
one of the first and second layers is resistant to permeation by hydrocarbons.
The tubing includes a third layer having a third predetermined radial thickness
greater than the thickness of the first layer. The third layer is capable of sufficiently
permanent laminar adhesion to the second layer to prevent delamination during said
desired lifetime of said tubing. The third layer is uniformly and homogeneously
connected to or bonded to the second layer and consists essentially of an extrudable,
melt-processible thermoplastic. At least one layer of the tubing is capable of
dissipating electrostatic energy in a range between about 10-4 to 10-9 Ohm/cm2.
