Kraft paper is a tough and waterproof wrapping paper, which is brown and widely used. It is often used to make paper bags, envelopes, record covers, documents and sandpaper. The quantitative range is 40 g/m2 to 120 g/m2, and there are differences between roll paper and plain paper, single side, double side and stripes. The main quality requirements are flexibility and firmness, high bursting resistance, and being able to withstand large tensile force and pressure without cracking.