WPP Valve Bag
WPP (Woven polypropylene) valve bag is a kind of PP woven block bottom bag with a valve opening on the top, made of woven polypropylene and printed BOPP film laminated to the outer surface.
PP valve bag is especially suitable for high-speed automatic filling of granular powdery materials. When filled, the valve port of bag will automatically close due to internal pressure.
Lower cost, better performance, PP valve bag is a good substitute for paper valve bag.