ZEER STERK LAMINAAT VAN THERMOPLASTISCHE POLYMEER- FOLIES ALSMEDE WERKWIJZE VOOR HET VERVAARDIGEN DAARVAN.

摘要

A high-strength laminate comprising generally weakly adhered biaxially oriented films, each formed of a blend which exhibits a distinct fibrous morphology with the fibres forming a distinct unidirectional grain when measured on a macro-scale but with the fibre-portions strongly deflected from this direction as seen on a micro-scale, the films being arranged in the laminate such that the unidirectional grain in at least two of the films criss-cross each other. This laminate is produced by melt attenuating the blend(s) while extruding the latter to films, cross-laminating the layers before or after solidification while they are still in molecularly unoriented state-except for the weak orientation produced by the melt-attenuation-and finally strongly biaxially orienting the laminate by stretching in several steps, whereby the stretching is generally uniaxial during each step.