PE thermal shortening film is widely used in beverage and beer fields in developed countries as an environmentally friendly packaging material with low cost, high production efficiency, excellent appearance and efficient logistics. It is also widely used in China's beverage and beer industries.

The annual use of PE thermal shortening film in Europe is more than 400,000 tons. The author has visited PLASTO, the third largest shortening film supplier in Europe. Its annual output value in 2003 was 55,000 tons, and the printed PE color shortening film was 28,000 tons, exceeding the output value of 27,000 tons of unprinted PE shortening film (commonly known as white film or plain film in the industry). Its specific composition is 28,000 tons of printing color film, accounting for 51%; other: 6,100 tons for glass bottle packaging, accounting for 11%; 8,600 tons for packaging paper packaging, accounting for 15%; 8,600 tons for milk packaging, accounting for 15% %; 3,700 tons are used for packaging of building materials such as bricks and tiles, accounting for 6%.

Since the domestic beer industry banned the use of bundled beer, PE shortened film packaging has appeared in the market at a low cost, and its use has increased year by year; then with Coca-Cola's promotion of PE shortened film in China instead of carton packaging, it has expanded from the beer industry to the beverage industry. . With the increasingly fierce competition in the terminal market, the low-cost advantage of PE shrink film packaging is increasingly favored by manufacturers. At first, the PE shortening film was presented in the shopping mall in the form of transportation packaging. After being delivered to the sales terminal, it needs to be broken and sold as a single piece. However, with the change of procurement methods in recent years, the direct sales trend of assembled packaging has become more and more obvious, which requires Printing the shortening film to improve the shelf display of the product provides an excellent opportunity for packaging manufacturers to increase the added value of the PE shortening film.

At present, the annual use of PE shortening film in China's beverage and beer industry is about 100,000 to 150,000 tons, accounting for about 50% of carbonated beverages, 20% of hot canned beverages, 15% of bottled water and 5% to 8% of beer. market share. With the rapid development of beverage and beer industries and the improvement of PE shrink film market share, it is estimated that in 2010 China's annual PE shrink film usage will exceed 600,000 tons, becoming the world's largest PE thermal shrink film market. The printed PE shortening film has an annual usage of 2000-2500 tons, accounting for only about 2% of the market share of PE shortening film, and the market share of about 50% in Europe is very far away and has infinite potential.

The PE shrink film is mainly produced by using LDPE with a melt index lower than 1 and using the single-bubble blown film technology to control the longitudinal and lateral shrinkage rate of the film through formulation, blow-up ratio, die gap and cooling. The main technical parameters of PE shortening film are shortening rate, physical and mechanical properties, friction coefficient and suitability of packaging machine. There are national standards for physical and mechanical properties such as shortening rate and tensile strength. The coefficient of friction primarily affects the stacking stability of packaged goods. The suitability of packaging machines is the most important goal of PE shortening film, which directly affects the film in packaging. Whether the machine can be used and how much power is used is mainly affected by the film formulation, but to a greater extent by the description level of the packaging machine.

At present, the production level of China's single-bubble PE film blowing machine has reached or approached the world-class level. The author uses the domestic three-layer co-extrusion film blowing machine equipped with film bubble inner cooling to produce thickness errors of ±5%, and shortening rate errors of ±5%. 3% high-transparency PE shortening film, of course, for general PE thermal shortening film that does not require printing, a single-layer film blowing machine can fully meet the needs of the product. Judging from the experience in Europe and the current production experience of printing shortening films in China, because of the thermal shortening characteristics and easy extension characteristics of the film, the printing of PE thermal shortening films needs to be printed with a satellite flexo printing machine. However, the current equipment of satellite flexo printing machines in China is very short, which will be the main factor restricting the development of printing PE thermal shortening film.

As the main material of LDPE, China currently only produces a small number of manufacturers such as Yanshan Petrochemical, and most of them rely on imports, and the quotations fluctuate greatly. In the long run, the demand for LDPE in China is increasing day by day, but both China and the world have newly opened polyethylene factories in 2008, all of which are LLDPE and HDPE factories. No new LDPE factory has been opened, which has expanded virtually. The most worrying point is the supply gap of LDPE.

At present, China has equipment and other hardware, and under the premise that the market demand is growing, the development of PE thermal shortening film will be subject to the supply of LDPE.