How to control the quality and performance of PE coated paper during the production process?

1. Raw material selection and preparation
The main raw materials of PE coated paper include paper and PE plastic particles. The selection of paper should be based on its characteristics such as strength, smoothness and water absorption to ensure that it is firmly bonded to the PE film and is not easy to peel off. PE plastic particles should be selected according to the product use, such as food grade, industrial grade, etc., to meet different performance and safety requirements.

During the raw material preparation process, the paper needs to be pre-treated, such as cleaning, drying, etc., to remove impurities and moisture on the surface and improve the bonding force with the PE film. At the same time, PE plastic particles also need to be screened and dried to ensure their purity and melting performance.

2. Melt extrusion and coating
Melt extrusion is a process in which PE plastic particles are heated to a molten state and then extruded into a thin stream through a screw extruder. The key to this step is to ensure the uniformity and stability of the melting of PE plastic particles. Heating temperature is a key factor affecting the melting state of PE plastic particles. If the temperature is too low, the PE plastic particles cannot be fully melted, affecting the extrusion effect; if the temperature is too high, the PE plastic particles may decompose and produce harmful substances. The speed, pressure and other parameters of the screw extruder will also affect the melting and extrusion effects of PE plastic particles. During the melt extrusion process, it is necessary to regularly detect the melt quality of PE plastic particles, including melt uniformity, viscosity and other indicators.

Coating is a process in which a thin stream of molten PE plastic is evenly coated on the surface of the paper. The key to this step is ensuring uniformity and consistency of coating. If the coating speed is too fast, the thin stream of PE plastic may not be evenly coated on the paper surface, causing problems such as missed coating and thin coating. If the coating speed is too slow, the production efficiency may be reduced. Coating thickness is an important factor affecting the performance of PE coated paper. During the coating process, the coating quality needs to be checked regularly, including coating uniformity, coating thickness and other indicators.

3. Forming and cooling of coated paper
Coated paper forming is a process in which paper coated with PE film is flattened and compacted through pressure rollers and other equipment to form a flat and smooth coated paper. During this process, the pressure and temperature of the pressure roller need to be controlled to ensure that the PE film and paper are tightly combined and not easy to peel off. At the same time, attention should be paid to adjusting the spacing and angle of the pressure rollers to adapt to different specifications of paper and PE film.

After the coated paper is formed, it needs to be cooled to solidify the PE film and improve its bonding force with the paper. During the cooling process, the cooling speed and temperature need to be controlled to avoid problems such as shrinkage and deformation of the PE film caused by excessive cooling.

4. Post-processing and quality control
After the production of coated paper is completed, post-processing is required, such as cutting, slitting, packaging and other processes. During this process, attention should be paid to maintaining the flatness and cleanliness of the coated paper to avoid defects such as creases and scratches.

Quality control is an important link in the production process of PE coated paper. Manufacturing enterprises should establish a complete quality management system and conduct comprehensive testing and monitoring of raw materials, production processes and products. At the same time, product quality assessment and user feedback surveys must be conducted regularly to identify problems and make improvements in a timely manner.

The production process of PE coated paper involves many fine links and requires comprehensive control from raw material selection and preparation, melt extrusion and coating, coated paper forming and cooling, post-processing and quality control. Only by ensuring that every link meets relevant standards and requirements can we produce high-quality, high-performance PE coated paper products.