Packaging materials refer to the general term used for manufacturing packaging containers, packaging transportation, packaging decoration, packaging printing, packaging auxiliary materials, and packaging related materials. Packaging materials generally include main packaging materials and auxiliary packaging materials. Commonly used materials include paper, metal, wood, plastic, textiles, ceramics, glass, grass, bamboo, rattan, willow branches, etc. Among them, plastic and metal materials are the most complex.
Packaging materials play an important role in the entire packaging industry, serving as a crucial foundation for developing packaging technology, improving packaging quality, and reducing packaging costs. Therefore, understanding the performance, application scope, and development trends of packaging materials is of great and far-reaching significance for the rational selection of packaging materials, expanding the sources of packaging materials, adopting new packaging materials and processing technologies, creating new packaging containers and packaging techniques, and improving the level and regularity of packaging technology.
1、 Performance of packaging materials
From the perspective of modern packaging functions, packaging materials should have the following performance aspects:
（1） Protect performance
Packaging materials should have a certain mechanical strength, adapt to temperature changes, be moisture-proof, waterproof, corrosion-resistant, UV resistant, heat-resistant, cold resistant, light resistant, oil resistant, etc., and should be odorless, non-toxic, odorless, and able to protect the quality of the contents intact.
（2） Operational performance
Packaging materials should have a certain degree of rigidity, heat sealing, and anti-static properties, as well as a certain degree of smoothness, plasticity, weldability, ease of opening, easy processing, easy filling, easy opening and closing, etc., suitable for automatic packaging machinery operation, and high production efficiency.
（3） Value added performance
Packaging increases the added value of goods, and good packaging greatly enhances the value and usability of goods. Especially as a sales packaging material, it is required to have good transparency, surface gloss, beautiful shape and color, and display effect, in order to enhance the value of the product and the purchasing desire of consumers.
（4） Convenient to use performance
No matter what material is used to package the goods, the basic requirements are easy to open and extract the contents, easy to reseal, good opening performance, and not easily broken or damaged.
（5） Reduce cost performance
Outdated packaging not only increases costs but also fails to achieve the expected results, so it is not advisable. When selecting packaging materials and methods in
practical applications, in addition to considering the above requirements, it is also necessary to consider saving packaging material costs, packaging machinery and equipment costs, labor costs, etc. The most suitable materials should be used, and the most reasonable packaging methods should be adopted to achieve the best results.
（6） Adapt to the nature of the product
The packaging of goods must be suitable for the nature of the goods. For example, silk heads, some of which are directly met with customers in stores, while others are processed, sorted, or made into clothes in factories. Their packaging should be different. The former should be more refined to highlight the quality characteristics of the silk, while the latter requires the goods to be smooth and wrinkle free, easy to open, and convenient for the factory to process. For example, polyurethane on-site foaming pad technology is a relatively new technological achievement that can increase the value of goods and protect their safety. However, using this type of packaging requires molding one by one, which is expensive and time-consuming. Therefore, it is currently only used to package valuable handicrafts such as carvings and antique porcelain. For general handicrafts such as wood carvings and ornaments, polyethylene plastic and bubble film packaging are sufficient.
