What is the production process of BOPP color thermosensitive synthetic paper?

The production process of BOPP color thermal sensitive synthetic paper is a complex and delicate process, mainly including the following steps:

1、 Raw material preparation and mixing

Main raw materials: Polypropylene (PP) resin, especially isotactic polypropylene, is mainly used, and its content needs to reach a high standard (such as 95%~97%) to ensure the tensile strength and physical properties of the film.

Functional fillers: Add functional fillers such as pigments, dyes, etc. as needed to give paper specific colors and functional properties.

Additives: including antioxidants, lubricants, fluorescent whitening agents, titanium dioxide, etc., to improve the processing performance of paper and the performance of the final product.

Mixing: Mix polypropylene resin, functional fillers, and various additives evenly in a certain proportion. The mixing process requires strict control of the proportion of raw materials and mixing quality to ensure the performance of the final product.

2、 Plasticization and Extrusion

Plasticization: Feed the mixed raw materials into an extruder for plasticization. The processing temperature of the extruder is generally around 250 ℃, and the specific temperature is adjusted according to the temperature resistance of the raw materials and the performance of the extruder.

Extrusion: During the plasticization process, the raw materials are melted into a uniform melt through high temperature and high pressure in the extruder, and extruded into thick sheets through the die.

3、 Casting and Cooling

Casting: extruding molten polypropylene into thick sheets.

Cooling: Use a cooling roller and a water tank to quickly cool the thick sheet into a regular thick sheet, with a temperature controlled at 30-45 ℃.

4、 Stretching treatment

Longitudinal stretching: The casting sheet is subjected to longitudinal stretching treatment, with a stretching ratio generally between 4.5 and 5.5. During the stretching process, it is necessary to control the temperature of the preheating zone, stretching zone, and shaping zone to ensure the uniformity and tensile strength of the film.

Lateral stretching: The casting sheet is subjected to lateral stretching treatment, with a stretching ratio generally between 9 and 10. Horizontal stretching also requires controlling the temperature and stretching speed of the preheating zone, stretching zone, and shaping zone to achieve bi-directional stretching of the film.

5、 Surface treatment

Perform corona treatment or other surface treatments on the stretched film as needed to improve the surface tension of the film and enhance the adhesion of the coating layer.

6、 Coating

Preparation of coating solution: Prepare coating solutions such as thermosensitive coating, primer, and protective layer, strictly control the composition, concentration, and coating amount of the coating solution.

Coating operation: Apply thermosensitive coating, base coating, protective layer, etc. on the surface of the film. The coating process needs to ensure that the coating is uniform and smooth.

7、 Roll up and slitting

Roll up: Roll up the coated film into a uniform large roll. During the winding process, it is necessary to control the tension of the contact roller and pressure roller to maintain the flatness and tightness of the large film roll.

Slitting: Cut large film rolls into appropriate sizes according to customer requirements. The slitting process requires strict control of slitting accuracy and edge quality.

8、 Timeliness processing and quality inspection

Aging treatment: The sliced film is subjected to aging treatment, usually completed within 24-48 hours, to improve the physical properties and stability of the film.

Quality inspection: Conduct quality inspection on the aged film, including appearance quality, physical properties, printing effect, etc., to ensure that the final product meets relevant standards and customer requirements.

9、 Packaging and Delivery

Packaging: Carefully package products that have passed quality inspection to ensure that they are not damaged during transportation.

Delivery: Deliver according to the agreed time, location, and method.

In summary, the production process of BOPP color thermosensitive synthetic paper involves multiple stages and details, requiring strict control of process parameters and quality requirements at each stage to ensure that the performance and quality of the final product meet customer requirements and industry standards.