The structure of printed packaging paper mainly includes the following parts:
Facing paper: Facing paper is the outermost layer of corrugated board, usually made of unbleached kraft paper, also known as boxboard. If a layer of bleached pulp is added to the top surface during papermaking, so that one side of the boxboard is white and the other side is original color, it is called white-faced boxboard, which is suitable for color printing.
Corrugated core paper: Corrugated core paper includes corrugated paper and double-corrugated and triple-corrugated middle paper. It is mainly made of semi-chemical pulp, with waste paper as the main raw material.
Lining paper: Lining paper is the innermost layer of corrugated board, usually of the same quality as facing paper, but the gram weight of lining paper is lighter than that of facing paper.
