For foods that are susceptible to moisture such as tea and biscuits, moisture penetration is the culprit of quality degradation. Tea, as a treasure gifted by nature, has its unique aroma and taste derived from complex chemical components. However, once moisture invades, the aroma components in the tea will evaporate quickly, and the tea flavor will become weak or even produce a musty smell. Similarly, biscuits are widely loved for their crispy texture, but the absorption of water will make the biscuits soft and lose their original flavor and texture. What's more serious is that the presence of moisture provides a breeding ground for the growth of microorganisms, which may lead to food spoilage and threaten consumers' health.
Facing the challenge of food susceptible to moisture, metallized CPP film, with its unique tight structure, has become a technological shield to protect food quality. The CPP (cast polypropylene) film itself has certain barrier properties, but the barrier properties of the CPP film after metallization have been significantly improved. The metallization process usually involves precision processes such as vacuum aluminum plating, so that an extremely thin layer of metal (mainly aluminum) evenly covers the surface of the CPP film. This metal layer acts like an invisible waterproof barrier, effectively blocking moisture penetration and providing solid protection for the dry environment inside the food.
The compact structure of metallized CPP films benefits from its special production process. During the cast extrusion process, the polypropylene raw material undergoes steps such as melting, extrusion, cooling and shaping to form a film with uniform thickness and smooth surface. The metallization treatment is based on this basis, and the metal layer is evenly attached to the surface of the film through processes such as vacuum aluminum plating. This metal layer not only improves the barrier properties of the film, but also gives it good gloss and aesthetics.
The waterproof performance of high barrier metallized CPP film is fully reflected in the packaging of food susceptible to moisture. For tea leaves, the tight structure of the metallized CPP film effectively blocks the intrusion of external moisture and maintains a dry environment inside the tea leaves, thus delaying the volatilization of aroma components in the tea leaves and maintaining the purity and lasting taste of the tea. The glossiness of the metal layer also adds a high-end feel to the tea packaging, improving the overall quality of the product.
In the packaging of crispy foods such as biscuits, metallized CPP film also demonstrates its excellent waterproof performance. The absorption of moisture is the main reason why biscuits become soft and taste bad. The tight structure of the metallized CPP film makes it difficult for moisture to penetrate, maintaining the crispy texture inside the biscuit. In addition, metallized CPP film also has certain tear resistance and heat sealing properties, ensuring the integrity and sealing of the packaging, further extending the shelf life of food.
In addition to its waterproof properties, metallized CPP films have many other advantages. For example, its good barrier properties are not limited to moisture, but can also effectively block the penetration of oxygen, odors and other substances, thereby further extending the shelf life of food. Metalized CPP film also has good transparency and gloss, which can clearly display the appearance and color of food and enhance the appeal of the product. In addition, metallized CPP film also has a certain degree of recyclability and environmental protection, which meets the requirements of the modern packaging industry for sustainable development.
As consumers' requirements for food quality and food safety continue to increase, the production technology of metallized CPP films is also constantly innovating and improving. From the selection of raw materials to the optimization of production processes to the further improvement of barrier properties, every step embodies the power of science and technology. For example, by improving the metallization process, the bonding force and uniformity of the metal layer and the CPP film can be further improved, thereby improving the barrier performance and aesthetics of the film. At the same time, by adding functional additives or using multi-layer co-extrusion technology, metallized CPP films can also be given more functional properties, such as antibacterial and antioxidant, to meet the needs of different food packaging.
The application prospects of metallized CPP film in the field of food packaging will be broader. With the advancement of science and technology and the changing needs of consumers, metallized CPP films will develop in a direction that is more environmentally friendly, more efficient, and more functional. For example, developing degradable and recyclable metalized CPP films to reduce the impact on the environment; realizing self-monitoring and regulating functions of packaging materials through nanotechnology or smart packaging technology to improve the shelf life and safety of food; and integrating with the Internet of Things technology to realize the traceability and tracking of food packaging information and improve the transparency and traceability of the food supply chain.
