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The base paper for paper cups is called "cup board", and is made on special multi-ply paper machines. It has a barrier coating for waterproofing. The paper needs high stiffness and strong wet sizing. The cup board grade has a special design for the cup manufacturing processes. The mouth roll forming process requires good elongation properties of the board and the plastic coating. A well formed mouth roll provides stiffness and handling properties in the cup. The basis weights of the cup boards are 170–350 g/m2.

To meet hygiene requirements, paper cups are generally manufactured from virgin (non-recycled) materials.[citation needed]The one exception to this is when the paper cup features an extra insulating layer for heat retention, which never comes into contact with the beverage, such as a corrugated layer wrapped around a single-wall cup.