The heat-sealing performance of heat-sealable metalized BOPP film is mainly achieved through two technologies: coating with heat-sealable resin glue and co-extrusion composite technology.
Coating with heat-sealable resin glue is an important step in the manufacturing process of heat-sealable metalized BOPP film. This step usually involves coating a layer of heat-sealable resin glue, such as PVDC (polyvinylidene chloride) latex, EVA (ethylene-vinyl acetate copolymer) latex, etc. on the surface of the BOPP film. These resin glues remain stable at room temperature, but can soften and bond when heated, thereby achieving heat sealing of the film.
During the coating process, the coating amount and uniformity of the resin glue need to be precisely controlled to ensure the strength and sealing of the heat-sealing layer. The coated film also needs to be dried to remove the solvent in the glue to avoid bubbles during the heat sealing process or affect the heat sealing effect.
Coextrusion composite technology is to mix the heat-sealable resin with the BOPP raw material in the extrusion stage, and extrude it through the coextrusion die to form a BOPP film with a heat-seal layer. This method can achieve a close combination of the heat-seal layer and the BOPP film and improve the heat-seal strength.
During the coextrusion composite process, the amount of heat-sealable resin added and the extrusion speed need to be precisely controlled to ensure the uniformity and stability of the heat-seal layer. The coextrusion die also needs to be designed and optimized to achieve a good combination of the heat-seal layer and the BOPP film.
Through the application of heat-sealable resin glue or coextrusion composite technology, the heat-sealable metallized BOPP film achieves heat-seal performance, which has significant advantages in the packaging process:
The heat-sealable metallized BOPP film's heat-seal performance makes it easy to seal during the packaging process. When heat-sealing on the packaging machine, the heat-seal layer of the film softens and bonds under heating to form a tight sealing structure. This sealing structure can effectively prevent product leakage and contamination, ensuring the quality and safety of the product.
The introduction of heat-sealing technology not only improves the sealing of the packaging, but also greatly improves the packaging efficiency. Compared with traditional mechanical or adhesive sealing methods, heat sealing technology is faster, simpler and more reliable. At the same time, the heat sealing process can also be automated, further improving the efficiency and consistency of packaging production.
The realization of heat sealing performance enables heat-sealable metallized BOPP film to be applied in more fields. For example, in food packaging, heat sealing technology can ensure that food is not contaminated and deteriorated during transportation and storage; in pharmaceutical packaging, heat sealing technology can keep pharmaceuticals dry and stable; in cosmetic packaging, heat sealing technology can protect cosmetics from external factors.
In order to ensure that the heat sealing performance of heat-sealable metallized BOPP film meets packaging requirements, strict quality control is required:
During the raw material procurement stage, BOPP raw materials and heat-sealable resins need to be strictly inspected and screened. Ensure that the quality of raw materials meets production requirements to avoid substandard heat sealing performance due to raw material problems.
During the production process, the coating or co-extrusion process needs to be monitored in real time. By monitoring parameters such as coating amount, extrusion speed, and temperature, the uniformity and stability of the heat sealing layer are ensured. At the same time, sampling and testing of finished products is also required to verify whether the heat sealing performance meets the requirements.
Before the finished product leaves the factory, a series of performance tests and evaluations are required. These include heat seal strength test, peel strength test, barrier performance test, etc. These tests can comprehensively evaluate the heat seal performance of heat sealable metallized BOPP film and its application effect in packaging.
Heat sealable metallized BOPP film achieves heat seal performance by coating heat sealable resin glue or co-extrusion composite technology, which has significant advantages in the packaging process. It can not only easily achieve sealing and effectively prevent product leakage and contamination; it can also improve packaging efficiency and expand the scope of application. In order to ensure that the heat seal performance of heat sealable metallized BOPP film meets packaging requirements, strict quality control is required. Through raw material inspection, production process monitoring, performance testing and evaluation and other measures, it can ensure that the heat sealable metallized BOPP film plays the best effect in packaging.
