Application Cases & Testing Date of Mono-material Structure with PVA Coated Barrier Film
For FLEXIBLE PACKAGING, the protection of the contents is indispensable. PE/PE structure itself has good water resistance and low moisture permeability, which can meet the packaging requirements of most contents, but the super-high OTR seriously affects the quality and freshness of the packaged contents.
(1) Oxygen Resistance
In order to improve the oxygen resistance of PE, Multilayer co-extrusion PE film with EVOH or PVA coated PE film are good solutions. Thereinto, a thin layer of 0.5g/m2 PVA can reduce the OTR value of PE film from over 1500 to around 3 (cm/m2.d.0.1mpa), and the coating layer also has good printing and laminated strength, which is very suitable for the PE/PE recyclable packaging structure.
(2) Moisture Resistance
Although PE film has low WVTR (WVTR value of 100u PE is about 89/m2.d), there are still some packaged products requesting better moisture resistance. We can achieve this by adding HDPE (H- PE/100 μ with WVTR value of about 2g/m2.d). Although the metallized PE film (Metallied PE/50u with WVTR value of 1.8g/m2.D) also has a good moisture resistance performance, metallized PE film will have the risk that PE slipping agent may separate out and transfer to the surface of the aluminum coating layer, resulting in the gradually weakening the surface performance of the aluminum coating and affecting the laminated adhesive strength.
| Structure | Type | Model | OTR (cm/m2.d.0. 1Mpa |
WVTR ( g/m2.d |
Application |
| H-APE40/H-PE60 | 6 colors printing | 100μm | 1. 3 | 2 | Vegetables & Fruits, Pet food |
| H-PE60/APE60 | 6 colors printing | 120μm | 1 | 2.7 | Vegetables & Fruits, Pet food |
| PE60/APE60 | 3 colors printing | 120μm | 1.2 | 6 | Lightweight Rice Packaging |
| ABOPE25/PE95 | White | 120μm | 1.2 | 3.8 | Vegetables & Fruits,Rice Packaging |
| ABOPE25/PE35 | White | 60μm | 2 | 8 | Vegetables & Fruits,Rice Packaging |
| BOPE25/APE95 | 6 colors printing | 120μm | 3 | 4.5 | Vegetables & Fruits,Rice Packaging |
| MDOPE25/APE60 | 6 colors printing | 85μm | 0.8 | 6 | FSS |
| AMDOPE25/PE60 | 6 colors printing | 85μm | 0.7 | 6 | FSS |
| MDOPE25/AMDOPE25/PE80 | 8 colors printing | 130μm | 0.3 | 0.6 | Mask Packaging |
PVA coated barrier film performs good barrier, especially oxygen barrier, which can be a good replacement of PVDC, EVOH etc, and helps to realize the visualization of content and lightweight packaging.
What’s more, PVA can be recycled together with PE due to their similar molecular structure and small usage of PVA. Taking mono PE structure as example, we can improve the PE barrier with PVA coating, or design various laminated structures to optimize the barrier performance of mono-material recyclable packaging solutions.
At present, except the difference of drop resistance, the other performance including heat sealing, flatness and laminated strength are almost the same between mono-material pouch and those with Nylon. And it is completely no problem for dry goods or other lightweight goods packaging.
