The main ingredients of stone paper are stone powder, added resin, etc. It is reported that there are three main production processes for environmentally friendly paper such as stone paper.
The first is the calendering method. That is, through batching, mixing, modification, extrusion, and calendering. The disadvantage of the calendering process is that it is complex. It is generally used to produce environmentally friendly paper products above 0.1mm. The product has a large proportion and the equipment is expensive, but the surface of the product is smooth. It is suitable for printing advanced samples and book covers.
The second is the casting method. By replacing the calender with a casting machine, it is possible to produce environmentally friendly paper of various thicknesses. However, the distribution of molecular chains in environmentally friendly paper is unidirectional, so the longitudinal, horizontal, and physical properties of environmentally friendly paper products are quite different. This is a major disadvantage of cast environmentally friendly paper.
The second is the biaxial stretching method. During the biaxial stretching process, some small gaps are formed between the base plastic and the filler, thereby reducing the proportion and cost of environmentally friendly paper. Because these small gaps have a pearly effect on light refraction, the environmentally friendly paper produced has a good appearance and has been widely used in packaging, printing, advertising and other fields.