The selection of surface layer raw materials is the key to ensure the gloss of low heat sealing temperature metallized CPP film. High-quality surface layer raw materials should have the following characteristics:
Good coating adhesion: The molecular structure in the raw material should have good compatibility with the metal coating to ensure that the coating can be firmly attached to the surface of the film and is not easy to fall off or peel off.
Excellent transparency: The raw material should have high transparency so that the metal coating can be clearly presented, thereby enhancing the overall visual effect of the product.
Suitable melting temperature: The melting temperature of the raw material should match the heating temperature during the metallization process to ensure that the raw material can be fully softened during the metallization process to facilitate the deposition and bonding of metal atoms.
Good weather resistance: The raw material should have a certain weather resistance to prevent the gloss from decreasing or the coating from falling off due to factors such as light and temperature during long-term storage or use.
Based on the above characteristics, the surface layer raw materials are usually selected from specially formulated and treated polypropylene (PP) resins. These resins undergo fine molecular design and synthesis processes to ensure that they meet the various requirements of the metallization process.
After selecting the appropriate surface material, it is also necessary to further improve its gloss through fine process treatment. It mainly includes the following aspects:
Raw material pretreatment: Before the raw material enters the production line, it needs to be strictly pretreated, including removing impurities, adjusting the particle size, etc., to ensure the purity and uniformity of the raw material.
Formula adjustment: According to the specific needs of the metallization process, the raw material formula is adjusted. For example, an appropriate amount of plasticizers, antioxidants and other additives can be added to improve the processing performance and weather resistance of the raw material.
Melt extrusion: During the melt extrusion process, parameters such as extrusion temperature, pressure and speed need to be strictly controlled to ensure that the raw material can be fully melted and evenly distributed on the surface of the film. At the same time, attention should also be paid to the cleaning and maintenance of the extruder to prevent impurity contamination and affect the gloss.
Cooling and shaping: The extruded film needs to be quickly cooled and shaped to fix its shape and gloss. The selection of parameters such as cooling speed and shaping pressure should be determined according to the characteristics of the raw materials and the specific needs of the metallization process.
In order to ensure the precise control of the glossiness of the surface layer of low heat sealing temperature metallized CPP film, the following strategies need to be adopted:
Raw material ratio optimization: Through experiments and practice, the raw material ratio is continuously optimized to find the best balance between coating adhesion and glossiness. This requires an in-depth understanding and accurate judgment of the performance of the raw materials.
Precise control of processing parameters: In key processes such as melt extrusion and cooling and shaping, various processing parameters such as temperature, pressure, speed, etc. need to be precisely controlled. This can be achieved through advanced automatic control systems and sensors to ensure the stability and controllability of the processing process.
Quality inspection and feedback: Set up quality inspection points on the production line to monitor and feedback key indicators such as film glossiness and coating adhesion in real time. Once quality problems are found, adjustments and improvements should be made immediately to ensure the quality of the final product.
Continuous improvement and innovation: With the continuous development of the market and technology, it is necessary to continuously improve and innovate the production process and raw material formula of low heat sealing temperature metallized CPP film. This includes exploring new sources of raw materials, developing new additives and technologies, etc. to enhance product performance and competitiveness.
As one of the important performance indicators of low heat sealing temperature metallized CPP film, its precise control is of great significance to improving the overall visual effect and attractiveness of the product. In the fields of food packaging and daily necessities packaging, films with bright and uniform gloss can attract consumers' attention and improve the quality and image of products. In addition, in the packaging of textiles, flowers, electronic components and other fields, low heat sealing temperature metallized CPP film with precisely controlled gloss also has broad application prospects.
