Barrier Performance and Structural Attributes

The defining technical attribute of PBL‑Transparent lies in its incorporation of an EVOH barrier layer. EVOH, as a copolymer characterised by high molecular chain regularity, exhibits strong intermolecular forces and low free volume, resulting in a pronounced suppressive effect on the permeation of oxygen and other gaseous molecules. Within the multi‑layer co‑extruded architecture, the EVOH layer is typically positioned between inner and outer polyolefin protective layers. Through optimised thickness ratios and layer arrangement, the material attains superior oxygen‑protection capability, effectively retarding oxidative degradation—including colour changes, flavour loss, and nutrient depletion—of packaged contents.

Notably, the EVOH layer does not compromise the transparency of the material. PBL‑Transparent achieves excellent protective performance while maintaining outstanding optical clarity, enabling concurrent fulfilment of protective and display functions. In terms of moisture protection, the outer polyolefin layers provide a reliable water‑vapour barrier, ensuring a balanced performance profile across both oxygen‑protection and moisture‑resistance dimensions.

Mechanical Performance and Process Compatibility

• Mechanical Properties and Chemical Resistance

PBL‑Transparent demonstrates robust mechanical strength attributes. The multi‑layer co‑extruded construction imparts excellent impact resistance and puncture resistance, effectively preserving packaging container integrity throughout filling, stacking, and transportation phases. The inherent toughness of the material ensures stable performance on automated high‑speed tube‑forming and filling lines, minimising process defects such as film rupture or cracking.

From a chemical resistance standpoint, EVOH exhibits good oil resistance and resistance to chemical solvents. This characteristic enables PBL‑Transparent, when packaging oil‑containing contents (e.g., mayonnaise, salad dressings, hand creams), to effectively resist the permeation and attack of oils and organic components on the barrier layer, thereby ensuring sustained protective functionality throughout the intended shelf life. Additionally, the chemical inertness of the material mitigates the risk of adverse interactions between packaging material and contents.

• Heat‑Seal Performance and Tube‑Forming Compatibility

PBL‑Transparent employs a PE‑based sealant layer, delivering robust heat‑seal strength and reliable closure integrity. In tube‑forming operations, the material feeds smoothly through both intermittent and continuous tube‑forming equipment, offering a broad sealing window that permits stable seal performance across a wide range of process parameters. Seal integrity is a critical quality indicator, directly governing the leak‑proof and contamination‑prevention capabilities of the finished package.