The quality of barrier material plays a key role in the service life of VIP. With the best barrier property, Al foil is widely used in barrier film for vacuum insulation panel. Moreover, there are many other kinds of barrier film, such as Al, EVOH, PVA, PA, MPET for the barrier function and LLDPE, CPP for heat sealing effect. As a compound of these above materials, Al foil barrier film has the extensive application in the market.
According to different requirements of thermal insulation and barrier property of barrier film, barrier films of different materials will be used to compound as a new kind of barrier film (three or five layers). As the service life of VIP is closely dependent on the barrier film, we will choose the suitable thickness of different barrier film for composite with right process to bring VIP with great barrier property and low edge effect into full play(VIP products may have some degree of edge effect due to the Al foil).
According to different customer requirements, we have three kinds of barrier films for selection including foil barrier film, hybrid barrier film and non-foil barrier film.
Hybrid barrier film is a kind of barrier film with half-metallized aluminum. Compared with the traditional barrier film, vacuum insulation panel based on hybrid barrier film has excellent thermal insulation and great barrier property to reduce the thermal bridge effect during the use of refrigerator and freezer.
With high barrier property, nanofiltration can maintain the degree-of-vacuum of vacuum insulation panel at a low thermal conductivity over a long period of time, reducing the edge effect of VIP. Based on the falling-head permeability tests, nanofiltration of superior performance is just as the optimal membrane AL7.
It can also prevent heat transfer and reduce the thermal conductivity across the edge of vacuum insulation panel.