Wisdom For Polyethylene
About multi-layered plastic bags
2024-12-24
About multi-layered plastic bags
A new film that combines the advantages of LDPE and HDPE
Recently, multilayer technology has been actively introduced into plastic bags.
In this technology, multiple circular dies are installed during inflation to extrude the resin in a multi-layer state, and the film and film are heat-welded together while the resin is still in the process of crystallisation.
The appearance of the film is entirely one sheet and it is not possible to determine whether it is multi-layered or not with the eye.
However, when the cross-sectional surface is observed with a polarising microscope, it can be seen that the layers overlap each other.
This technology is used when the required specifications cannot be met with conventional LDPE or HDPE bags alone. A new film can be created by combining the advantages of each by making them multi-layered.
In addition, it is also possible to produce plastic bags with excellent opening properties using HDPE on the inside, and plastic bags with excellent slip properties using HDPE on the outside.
In some cases, the same LDPE is used to produce multi-layered bags for beverages. We adopt this process for the product-contacting inner layer with an additive-free or low-odour type film and outer layer with metallocene catalyst film with good pinhole characteristics.