| abstract |
The invention discloses a composite heavy packaging film, comprising, from exterior to interior, a kraft paper layer, a PET polyester layer, an AL layer and a three-layer co-extruded polyethylene layer. Compared with the prior art, the invention has the following advantages: through usage of a composite structure, AL of a barrier layer can be effectively protected and is prevented from easy fracture; through mutual cooperation of a plurality of substrates, the composite heavy packaging film has good environmental suitability and barrier properties and adapts to packaging of a variety of large-volume contents. |