Process characteristics of multi-layer co-extruded barrier films, explained by easy-peel film manufacturers

Easy Peel Film Manufacturer's View Multilayer co-extruded barrier films are generally produced using multilayer co-extrusion blow molding or casting processes. Multilayer co-extrusion offers excellent barrier properties, mechanical properties, stretch forming performance, and heat sealing performance. It does not require lamination during processing, nor does it involve residues of inks, adhesives, or additives, making it a relatively green and cost-effective food packaging technology.

　　Easy Peel Film Manufacturer's View Multilayer co-extruded barrier films refer to resin raw materials with different functions, such as polyethylene, polypropylene, nylon, ethylene -vinyl alcohol copolymers, etc. These are distributed, melted, and extruded by three or more extruders, then merged through their respective channels at the multilayer co-extrusion die, followed by cooling and lamination after blow molding or casting to prepare multilayer co-extruded films. This collects and designs the advantages of different resins, enabling the production of films with comprehensive performance and various packaging requirements.

　　Easy Peel Film Manufacturer's View The structure of multilayer co-extruded barrier films can combine materials with different properties as needed, giving the film multiple functionalities simultaneously. For example, heat sealing and packaging machinery require films with good processability, so the multilayer structure uses MDPE or HDPE materials to improve the film's strength and firmness, ensuring good processability, while the inner layer uses metallocene (HAO) polyethylene material with good heat sealing performance, giving the film excellent heat sealing and mechanical properties to better meet packaging needs. Materials like PA, EVOH, PVDC can be selected to meet different barrier requirements.

　　Easy Peel Film Manufacturer's View Multilayer co-extruded barrier film technology is a one-step multilayer co-extrusion forming process that does not require traditional post-processing steps such as lamination or coating, effectively reducing raw material and production process costs, saving production costs, and enabling the feasibility of film thickness reduction.

Easy Peel Film Manufacturer's View Through structural design, various materials can be combined in different ways to fully utilize the characteristics of different raw materials, and different structural layers can be designed according to different packaging applications. Moreover, the more co-extruded layers, the more flexible the structural design.

　　Easy Peel Film Manufacturer's View The symmetrical structural layers of multilayer co-extruded barrier films consist of three functional layers: barrier layer, adhesive layer, and support layer.

　　Barrier Layer: Easy Peel Film Manufacturer's View The barrier layer has functions of oxygen resistance, moisture resistance, and oil leakage prevention. By controlling the material and thickness of the barrier layer, the barrier performance of the film material can be adjusted to meet different packaging needs.

Support Layer: Easy Peel Film Manufacturer's View Generally, symmetrical structural materials have two support layers. The inner layer is used for heat sealing, called the heat seal layer, and the outer layer serves directly as the outer layer of the packaging film or as the printing layer for printing. The support layer requires good mechanical strength, heat sealing performance, water vapor barrier properties, transparency, and printability. Common materials for this layer are low-density polyethylene or low-density polyethylene /LLDPE blends.

Adhesive Layer: Easy Peel Film Manufacturer's View The adhesive layer is used to bond the barrier layer and support layer to ensure interlayer peel strength. The choice of adhesive layer material and thickness usually depends on the materials of the support and barrier layers and the required bonding strength.