(IV) Metal materials for packaging and their characteristics
There are many kinds of metals, and the packaging metal materials are mainly steel materials, aluminum materials and alloy materials. Steels used for packaging include thin steel plates, galvanized low-carbon iron plates, and tin-plated low-carbon steel plates (commonly known as tinplates); packaging aluminum plates include pure aluminum plates, alloyed aluminum plates, and aluminum foils. Metal materials have the following advantages:
1. It has good mechanical strength, strong and firm, collision-resistant, and not broken, and can effectively protect the contents.
2. Excellent sealing performance, good barrier property, airtight, food packaging (canned) can achieve medium and long-term preservation.
3. With good extensibility, easy to process and shape. Moisture-proof, light-resistant, for
4. The metal surface has a special luster and is easy to paint and print.
5. Easy to recycle, no pollution to the environment.
Metal materials have many advantages, so they are often used as packaging, but there are also some unavoidable disadvantages, especially the relatively poor chemical stability, prone to rust in the humid atmosphere, the case of acid and alkali corrosion, so the packaging is subject to certain Limits, practical applications, often outside the steel plate galvanized, tin plated, chrome plated or coated to improve its acid and alkaline resistance and corrosion resistance, but the cost increases. Therefore, the current rigid metal materials are mainly used for the manufacture of transport packaging drums, containers and beverages, food and other goods sales packaging cans, listening, boxes, as well as a small amount of caps and tying materials used to process various bottles and cans. For example, heavy-duty steel cylinders and steel tanks are used to store acid liquids and gases that are compressed, liquefied, and dissolved; thin steel drums are widely used to hold various types of edible oils, petroleum, and chemical products; aluminum and aluminum alloy barrels are used for holding Alcohol and various foods; galvanized sheet steel drums are mainly used to contain powdery, pasty and liquid products; iron-plastic composite drums are suitable for holding various chemical products and corrosive and dangerous goods; tinplate cans, chrome plated steel Cans are important containers for canning and beverage industry; metal tins and boxes are suitable for holding biscuits, milk powder, tea, coffee, cigarettes, etc. Soft metal materials are mainly used in the manufacture of hoses and metal foils. For example, aluminum hoses are widely used for packaging paste cosmetics, pharmaceuticals, cleaning products, stationery, foods, etc.; aluminum foils are often used for the manufacture of composite packaging materials, and are also commonly used Food, cigarettes, medicines, cosmetics, chemicals and other packaging.
(v) Glass and Ceramics for Packaging
Both glass and ceramics are inorganic materials with silicate as the main component. Glass and ceramics have a long history as packaging materials, and glass is still one of the main materials for modern packaging.
1. glass.
Glass, with its own excellent characteristics and continuous progress in glass manufacturing technology, can adapt to the needs of modern packaging development. Its characteristics are as follows:
(1) Good chemical stability, corrosion resistance, non-toxic and tasteless, health and safety.
(2) Good sealing, airtight, moisture-proof, UV-shielding, constant strength, and effective retention of contents.
(3) It has good transparency and is easy to be modeled. It has special effects of publicizing and beautifying goods.
(4) Rich sources of raw materials and low prices. m
(5) It is easy to recycle, reuse, and regenerate, which is conducive to environmental protection.
Glass is used as a packaging material, and has the disadvantages of low impact strength, easy breakage during collision, large weight, high transportation cost, large internal consumption, and the like, which limits the application of glass. At present, the strengthening and lightweight technologies of glass and composite technologies have been developed to some extent, and the adaptability to packaging has been strengthened. Glass is mainly used to manufacture and sell packaging containers such as glass bottles and glass jars, and is widely used in the packaging of alcoholic beverages, canned foods, condiments, medicines, cosmetics, chemical reagents, and stationery. In addition, glass is also used in the manufacture of large-scale transport packaging containers for storage of strong acid products; it is also used to manufacture glass fiber composite bags for packaging chemical products and mineral powders.
2. ceramics.
Ceramics have good chemical stability and thermal stability, acid and alkali resistance, excellent shading, good sealing, and low cost, can be made into a variety of packaging containers such as cylinders, tanks, jars, bottles, etc., widely used for packaging various fermentation Food, pickles, pickles, pickles, seasonings, egg products, and chemical raw materials. The ceramic bottle is a sales and packaging container for alcoholic beverages and other beverages. Its structural shapes are diverse, simple and elegant, and the glaze and patterns are beautifully decorated. It is particularly suitable for the packaging of high-grade wines.
(6) Other packaging materials
Wood has a special ability to withstand pressure, impact and weather, and has good processing performance, is still an important material for large and heavy commodity transport packaging, also used to package those small quantities, small size, weight, strength High demanding goods. Common wooden packaging includes wooden boxes and wooden barrels. Although wood has unique advantages as a packaging material, due to the scarcity of forest resources, environmental protection requirements, and high prices, its development potential is not great. At present, wooden packaging containers have been gradually reduced and are being replaced by other packaging containers. The fabric materials used for packaging are mainly cotton and hemp plant fibers, followed by mineral fibers and chemical fibers. They are mainly used for bagging and wrapping goods. For example, cloth sacks and sacks have suitable fastness, light weight and convenient use, and are suitable for containing food and its products, salt, sugar, agricultural and sideline products, chemical fertilizers, chemical raw materials, and Chinese medicinal materials. Bamboo, wild vines, branches and grasses are materials that are widely sourced and inexpensive. The containers made from them have the characteristics of ventilation, light weight, solidity, and unique shape, and are suitable for packaging various agricultural and sideline native products.