What is the production process of BOPP color synthetic paper?

The production process of BOPP (Biaxially drawn polypropylene) color synthetic paper is a complex and delicate process involving several key steps. The following is a general description of the production process:

First, raw material preparation

1.Polypropylene resin: The main raw material of BOPP is polypropylene resin, which requires a high molecular weight, narrow molecular weight distribution and good processing performance. The choice of polypropylene resin directly affects the physical properties and chemical stability of the final product.

2.Pigments and auxiliaries: In order to produce colored synthetic paper, it is necessary to add the right amount of pigments to obtain the desired color. At the same time, it is also necessary to add antioxidants, antistatic agents, smoothing agents and other additives to improve the performance of the film, such as improving weather resistance, antistatic ability and fluidity during processing.

Second, mix ingredients

Polypropylene resin, pigment and additives are added to the high-speed mixer according to a certain proportion, and are fully stirred and mixed to ensure the uniform distribution of raw materials. This step is essential to ensure the color consistency and physical properties of the final product.

Third, extrusion casting

The mixed raw materials are melted and extruded by the extruder to form a certain thickness sheet. The extrusion process requires strict control of temperature, pressure and extrusion speed to ensure the quality and thickness uniformity of the sheet. The extruded sheet is quenched to quickly cure the sheet and maintain its shape.

Fourth, bidirectional stretching

The extruded sheet is stretched bidirectionally, that is, lengthwise and transversally at the same time. The stretching process needs to be carried out under certain temperature and tension conditions to increase the strength and toughness of the film, and improve its optical properties and dimensional stability. Bidirectional drawing is one of the key steps in BOPP production and has a decisive impact on the performance of the final product.

Fifth, heat treatment and cooling

The stretched film requires heat treatment to remove internal stress, increase dimensional stability and further improve physical properties. Precise temperature and time control is required during heat treatment to avoid film deformation or aging. After the heat treatment is completed, the film is cooled to fix its shape and properties.

Sixth, trimming and slitting

After heat treatment and cooling, the film may have irregular edges or widths that do not meet the requirements, so it needs to be cut. After that, according to market demand and product specifications, the film is cut into rolls of a certain width and length.

Seventh, follow-up Treatment (Optional)

Depending on the needs of the specific product, subsequent processing steps such as corona treatment and coating may also be required. Corona treatment can improve the wettability and adhesion of the film surface, which is conducive to the subsequent printing or composite processing. Coating can form a functional coating on the surface of the film to give it specific properties such as waterproof, oil resistant, anti-stick and so on.

Eighth, quality inspection and packaging

Finally, the quality inspection of the produced BOPP color synthetic paper is carried out to ensure that the product meets the relevant standards and customer requirements. Qualified products will be packaged and stored for sale.

It should be noted that the above process is only a general description and may vary in actual production due to equipment, process, raw materials and other factors. In addition, with the continuous progress of science and technology and the constant change of application needs, the production process of BOPP color synthetic paper is also constantly optimized and innovative.