Three- or four-layer kraft paper bags can be coated with a PP film on top for waterproofing. Imported Russian yellow kraft paper or Canadian white kraft paper can be used. PE inner film can be added. Multi-layer kraft paper bags are made from pure wood pulp kraft paper and are more environmentally friendly. PE plastic inner film can be added for even better moisture-proofing.

The outer layer is made of refined white kraft paper or yellow kraft paper, and the inner layer is made of PP plastic woven cloth. The PP plastic particles are melted under high temperature and high pressure, and the kraft paper and PP plastic woven cloth are laminated together. PE plastic inner film bags can be added to improve moisture-proof effect.

The outer layer is made of refined white or yellow kraft paper, and the inner layer is PP plastic woven cloth. The PP plastic particles are melted under high temperature and high pressure, and the kraft paper and PP plastic woven cloth are laminated together. The outermost layer is covered with a layer of BOPP film, which is not only moisture-proof, but also has an attractive appearance and is resistant to stains. PE plastic inner film bags can be added for even better moisture-proofing.