Glass is one of the most commonly used packaging materials. The main characteristics of glass packaging materials are aesthetics, hygiene, corrosion resistance, low cost, and are inert materials with low environmental pollution. Milk, soft carbonated drinks, alcohol, and jams are commonly used in glass containers. Glass packaging containers have the following advantages: good chemical stability; good barrier properties, hygienic and storage properties; generally not deformed; easy to seal with a lid, can be tightly sealed again after opening; easy to beautify; raw materials rich and low cost. Milk, soft carbonated drinks, alcohol, and jams are commonly packaged in glass containers. Some cooking utensils and cutlery are also packaged in glass. The disadvantages of glass packaging materials are fragile and bulky. From the perspective of the development of foreign glass packaging materials, glass bottles for food packaging are being developed to increase the strength and light weight (thin-walled) of glass. Lightweighting and thinning will inevitably affect the strength of the glass container. In addition to adopting a reasonable structural design, the solution to this problem is to use chemical and physical strengthening techniques and surface coating strengthening methods to improve the physical properties of the glass. strength. At the same time, it is necessary to improve the performance of glass, especially the recycling of glass packaging products and the modification of its fragile, reducing the energy consumption and raw material consumption of individual glass packaging containers.
2, plastic packaging materials
It has light weight, easy to use, barrier, permeability, heat resistance, cold resistance, good corrosion resistance, and the appearance of colorful appearance, beauty and other characteristics. Because of its rich source of raw materials, low cost, and excellent performance, it has been widely used in food packaging, and has gradually replaced traditional packaging materials such as glass, metal, and paper, resulting in a tremendous change in the appearance of food packaging. It is worth noting that plastic packaging materials have a prominent drawback, they are not easily degradable, and incineration can produce toxic gases. Moreover, plastic packaging materials belong to the shortest period of use of plastic products, generally 1 month to 3 months, the longest year, after which mostly become municipal solid waste into the garbage disposal system, and some are discarded, resulting in "white Pollution". Plastic packaging materials account for the largest proportion of waste, and their environmental pollution is also the most serious of all types of packaging materials. The current treatment scheme combines the use of recycled plastics for recycling and development. In addition, due to the defects of the plastic products, the overall moisture resistance and barrier properties are not as good as those of metal and glass containers. Therefore, the existing plastic properties are improved, new varieties are developed, strength and barrier properties are improved, consumption is reduced, and reuse, classification and recycling are performed. It is very important.
3, paper packaging materials
In the modern packaging industry system, paper and paper packaging containers occupy a very important position, accounting for 40% to 50% of all packaging materials. Compared with other materials, it has a series of unique advantages: good processing performance, excellent printing performance, certain mechanical properties, easy composite processing, good lineage, good hygienic safety, and wide range of raw materials, various types, and low cost , easy to form mass production, paper packaging containers lighter weight, good cushioning, widely used, waste can be recycled, no white pollution. With the increase in people's awareness of environmental protection and the actual needs of life, the development of plant fiber snack boxes, the development of natural green packaging materials, etc. will be the trend of future paper products food packaging materials. In addition, with the rapid development of packaging technology, edible wrapping paper is an important development direction of modern food packaging. This package has important environmental and economic value. At present, there are two kinds of foreign edible papers, one is using vegetables as the main raw material, and the vegetables are dried after molding; the other is the gelatinization of starch, sugar, adding other food additives, and the method of molding similar to papermaking. From the application and development prospects, green products based on vegetables have more potential for development.
4, metal packaging materials
Its excellent performance includes: high barrier property, excellent mechanical properties, good processability of container molding, good resistance to high and low temperature, thermal conductivity and thermal shock resistance, good surface decoration, and easier recycling of packaging waste. Canned foods, as well as some liquids, pastes, powders, or high-grade foods, use this type of packaging material. Commonly used metal packaging materials are tinplate and aluminum, which are widely used in the manufacture of food and beverage cans.
In recent years, the changes and development directions of metal cans are:
(1) Improve the strength of materials, reduce the thickness of the substrate, save the amount of metal materials to a greater extent, reduce costs, and reduce the impact on the environment;
(2) reduce the amount of tin plating tinplate;
(3) Aluminum tin cans are made of tinplate. Due to the high cost of aluminum and the unstable value, various countries have adopted tinplate instead of aluminum to produce food and beverage cans;
(4) Using resistance welding to achieve lead-free pollution;
(5) Using aluminum foil instead of plastic and paper, aluminum foil is very easy to recycle and has almost no pollution to the environment. Therefore, the use of aluminum foil instead of plastic and paper is a good development direction.