Polyethylene Terephthalate (PET) was named as PET because of the repeated Ethylene and Terephthalate. The ester in the polyester shows electrical negative charge because of the big electro negativity. It also shows polarity with hydrogen showing positive reaction in contrast to the carbonyl oxygen. The melting point is 265℃ and the thermal transformation temperature is 240℃. Furthermore, the continuous heat-resisting temperature is 140℃ where the thermal resistance is outstanding. The molding product is hard and the machinery strength is strong. The electrical characteristic is excellent with good weather protection. The stress cracking ability is outstanding and the surface gloss is also excellent for clear coloring and fair coating.
Vacuum Forming includes the process of heating and softening the sheet or plate that is made through calendar method or extruded molding method in the order of vacuuming the air inside the mold and then formation by pushing the sheet or plate in to the mold with air pressure. Usually, this is a method used to manufacture thick containers such as egg packs, trays, plastic cups, or cracker cases.