Woven Polypropylene Bag Suppliers & Manufacturers

Woven PP bag construction types and specifications

Woven polypropylene (PP) bags are produced by weaving flat PP tape yarns (PP raffia) into a tubular woven fabric, then cutting and sewing into bag formats. They are the dominant bulk sack format for agricultural commodities, food products, and industrial dry goods globally — used for packaging rice, flour, sugar, maize, starch, feed, fertiliser, cement, sand, seeds, and chemical powders. Construction variants: unlaminated woven PP bags — the natural weave provides good strength and is breathable (allows moisture vapour exchange) — suitable for products that require ventilation (potatoes, onions, wood pellets) or where moisture ingress is not a concern; standard for cement, sand, and fertiliser. PP laminated bags — the woven PP fabric is coated with a thin BOPP or PP film laminate, producing a smooth printable surface with improved moisture resistance and a better barrier against fine dust leakage — the standard for food products (flour, rice, sugar, salt) and branded consumer-facing sacks. BOPP-laminated (block bottom) bags — a premium variant with a BOPP outer film laminated to the woven PP, producing a flat-bottom stand-up bag that can bear high-quality multicolour print — used for premium flour, animal feed, fertiliser, and branded commodity packaging where shelf or retail presentation matters. Inner PE liner: woven PP bags for moisture-sensitive food products (flour, starch, salt) often incorporate a stitched-in or inserted PE film liner to provide a complete moisture barrier. Bag closure types include: sewn open mouth (standard — the filled bag is sewn closed on the production line), valve-sealed (a self-closing valve in one corner allows filling and self-seals under the weight of the product), and heat-sealed (for laminated bags with a compatible sealing layer).