Abstract A container suitable for liquid hydrocarbons which comprises an internal pinched seam container having a hydrocarbon barrier as an inner liner. The container is prepared by releasably attaching first and second curable flexible sheets over the apertures of first and second concave molds, shaping the sheets by applying a pressure differential between the surface of each sheet facing its associated mold; after shaping the first sheet, providing an aperture therein through an aperture in the corresponding mold; adhering the peripheries of the two sheets together, before or after shaping the first sheet, and providing an opening in one of the sheets; curing the sheets after shaping to form a pinched seam container; removing the container from the molds; turning the container inside out through the provided opening therein; and sealing the said provided opening.
The method of claim 1 wherein said provided opening is formed by providing an insert between a portion of the peripheries of the two said flexible uncured sheets to which their uncured polymeric layers will not tightly adhere when cured and removing said insert after curing the sheets.
Claim 2
Dependent Claim
39 words
The method of claim 1 wherein the flexible sheet comprises a rubbery copolymer of 1,3-butadiene and acrylonitrile in admixture with from about 10 to about 60 parts of polyvinyl chloride per 100 parts by weight of said rubbery copolymer.
Claim 3
Dependent Claim
84 words
The method of claim 3 wherein the hydrocarbon barrier layer on the flexible sheet comprises at least one material selected from the group consisting of nylon, polyvinylidene chloride and a polyester having the structure derived from at least one dicarboxylic acid selected from terephthalic acid and isophthalic acid with at least one straight chain glycol having from two to 10 carbon atoms where the ratio of units of the polyester derived from terephthalic acid to isophthalic acid is from about 20:80 to about 100:0.