Inner Liner

Inner Liner is a packaging industry term that specifically refers to the flat paper layer adhered to the inner side (usually single-faced or double-faced) of the corrugating medium in a corrugated board structure. It also generally refers to the lining paper in various packaging containers (such as cartons, boxes, and paper drums) that directly contacts the goods on the inner wall. In foreign trade, Inner Liner commonly appears in specifications for paper products, packaging materials, printed materials, etc., to clarify material, grammage, color, and environmental requirements. Usage scenarios include: quality clauses in procurement contracts, goods descriptions in letters of credit, and packaging instructions in packing lists. Notes: Inner Liner is opposite to 'Outer Liner'; the former focuses on protection and hygiene of the contents, while the latter emphasizes printing and strength. It differs from 'Corrugating Medium' in that the medium is wavy, while the inner liner is flat. Foreign trade practitioners should pay attention to differences in environmental standards (such as FSC, REACH) and grammage units (gsm) for inner liners across countries to avoid rejection due to specification mismatch. In addition, Inner Liner sometimes also refers to the inner wrapping paper of a roll of paper, and the context should be considered.