Due to the special requirements of chemical industry, cement, fertilizer, sugar and other industries on packaging, quite a few plastic woven bags need to have waterproof sealing function. At present, there are two types of waterproof sealed woven bags widely produced and applied in our country: one is the ordinary separated woven bag with outer woven bag and lining film bag, and the other is the multifilm woven bag coated with a layer of plastic film on plastic woven cloth.