Composite laminated thermoplastic preform - for thermoformed articles with hollow spaces forming reinforcement ribs

摘要

Composite laminated thermoplastic preform esp. for the manufacture of hollow thermoformed articles having a complex pattern of hollow spaces forming reinforcement ribs e.g. plates for electronic components, is composed of at least two laminated thermoplastic sheets, the internal face of at least one of the sheets, pref. both sheets, being provided with passages for fluid circulation. The thermoplastic material is pref. polyethylene, polypropylene or polyethylene terephthalate opt. contg. 1-70% wt. filler. Provides rapid thermoforming cycles and better reproduction of the mould.