Method of manufacturing laminated flexible tubes
AssigneeCebal
InventorMichel Bosshardt
Life of this patent
Estimating the term…
Abstract
A manufacturing process for flexible tube skirts including the steps of providing a multi-layer plastic film, cutting out a strip from the multi-layer plastic film, producing a cylindrical sleeve by rolling-welding the strip, and cutting out the sleeve to the desired length to obtain the tube skirts. The strip is cut out from a multi-layer plastic film which has a symmetrical structure in relation to its median plane, with symmetrical layers having the same thickness and made of the same plastic, having the same chemical composition and the same molar mass.
Claims34
A flexible tube skirt, made up by stacking an odd number of layers of plastic to form a film having a central layer and one or more pair/s of non-central symmetrical layers, wherein each pair of the non-central layers is disposed on either side of the central layer, and each pair of the non-central layers has the same rank, one layer in the centrifugal radial direction, the other in the centripetal radial direction, each pair of the non-central layers has substantially the same thickness and is substantially made from the same plastic material, in that each pair of the non-central layers consists of a polymer or a mixture of several polymers in identical proportions, said polymer(s) being produced from monomers with the same chemical composition and having substantially the same average molar mass, and
- wherein the average Young modulus of the plastic in the central layer is lower than the average Young modulus of the plastic in the non-central layers.
A flexible tube skirt according to claim. 3, wherein said central layer is a material selected from the group consisting of low density linear polyethylene hexene copolymers (LLDPE), very low density polyethylenes (VLDPE) with a density ranging between 0.88 g/cm3 and 0.93 g/cm3, polyethylenes obtained with metallocene single-site catalysts, ethylene vinyl acetate copolymers, and grafted copolymers.
Dependencies are inferred from the claim text.