Cartonplast is a trademark that was first given by Covema spa (Italy) in the early seventies to a specific model of extrusion line manufactured and sold world wide by the aforesaid.In subsequent years such name was used as well to identify the product made by a Cartonplast extrusion line that is to say plastic corrugated sheet as well known as plastic hollow profile sheet or plastic twin wall sheet. The main raw material used to manufacture Cartonplast sheets are PP (polypropylene) and PET (Polyethylene terephthalate).The Cartonplast extrusion is carried out by using a unique front spinneret plate applied to a flat T-die equipped with restrictor bar (this technology was invented and patented by Marco Terragni during the seventies) to enable using thermoplastic polymers with different MFI (range 0.9 to 3).