Synthetic paper is known as "Tearable" paper. Currently, it is popularly called "stone paper." This title is debatable. I think that it should be "synthetic paper" is more scientific. Synthetic paper has more than 30 years of development history in Europe, America, and Japan. Domestic production began trial production more than ten years ago. Domestic trial production began more than ten years ago. However, at the time, the production costs of plain paper and synthetic paper were inversely related to the market price, and they were not widely promoted.
The stone paper uses inorganic powder (mainly calcium carbonate) as the main raw material, adds a small amount of synthetic resin and plastic additives, and adopts advanced technology to produce new environmentally friendly synthetic paper, which is widely used in printing, packaging, cardboard and various Labels, etc. With excellent paper properties and environmental performance, it is the second major technological change in paper production.
Stone Paper Production Process:
1. Special masterbatch production process
Synthetic resins (chloropropene, polyethylene, polystyrene, etc.), chemical additives (plasticizers, lubricants, brighteners, stabilizers, etc.), inorganic powders (calcium carbonate, talc, silicon) Graystone, zeolite, titanium dioxide, etc.) Blending - Extrusion - Granulation - Specialty masterbatches.
2. Rolling production method:
, resin-coextrusion-calendering-preheating-stretching-styling-corona, treatment-coating-slicing-winding-inspection-finished product.
Rolling production method features: high efficiency, good quality, smooth paper, can be used for high-grade printing paper.
Disadvantages: complicated process and expensive equipment.
3. Casting production method
The process flow is similar to the calendering process
The casting method is characterized by a certain speed difference between the extrusion speed of the die and the rotation of the casting roll. A uniaxial tension is formed between the meniscus and the cooling roll extruded from the die. According to product requirements, the synthesis is different. Paper thickness can be adjusted. With good rigidity, toughness, good tensile strength and so on.
4. Blown film production method
Upward blowing and down blowing
Features: high yield, simple process, uniform product thickness. Disadvantages: high resin content, paper width, and thickness are limited.
5. The two-way stretching production method
The biaxial stretching method adopts an extrusion process similar to that of rolling and casting. After the biaxial stretching system is installed, the physical properties of the synthetic paper in the longitudinal and transverse directions are substantially similar after longitudinal and transverse stretching.
Two-way stretching production method features: Advantages: low production costs, coloring, moisture absorption, surface gorgeous, high-grade paper exquisite, do drawings, painting, instrument cardboard, pictures, fine quality packaging. Disadvantages: The process equipment is complex and the technical difficulty is high, but the process will be the development direction of synthetic paper.
6. The non-woven paper production method
After the raw and auxiliary materials are melted, ultrafine filament yarns are extruded and rolled to form non-woven synthetic paper. There are many similarities between the non-woven process.