Among plastic packaging materials, the market demand for film materials increased the most, accounting for 46% of the total plastic packaging materials. The plastic packaging film mainly includes: heat shrinkable packaging film, wrapping packaging film, food aseptic packaging film, fruit and vegetable cling film, liquid packaging film and the like. With the continuous improvement of the equipment level of China's plastic film industry, some have reached the advanced level of developed countries, and a number of new products have emerged. For example, the biaxially stretched film as a composite packaging substrate not only overcomes the long-term import situation, but also It still exports about 300,000 tons per year and earns more than 3 billion US dollars. The number of large-scale packaging film manufacturing enterprises in China has developed rapidly, and now it has reached 2,240, among which a number of leading enterprises in the industry have emerged, such as Jiangyin Shenda Group, Zhejiang Dadongnan Plastic Group, Foshan Oriental Packaging Materials Company, Foshan Dubang Hongji. Packaging companies, etc., they play a pivotal role in the industry.
1, heat shrinkable packaging film
At present, PVC heat shrinkable film is gradually decreasing in China, and heat shrinkable films such as PE, PP, PET, PVDC, and Pa are developing rapidly, and a multilayer co-extruded composite heat shrinkable film has appeared. Taking the three-layer co-extruded heat-shrinkable film which is currently used most, the film is a three-layer composite heat-shrinkable film with linear low-density polyethylene as the intermediate layer and co-extruded polypropylene as the inner and outer layers, since it has both PE and The advantages of PP are better than single layer PE film and PP film. Nearly 20 companies in the industry have produced heat-shrinkable films, and their production capacity has grown from 40,000 tons to nearly 80,000 tons. Among them, Baoshuo Group, Tianjin Shengda, Fuzhou Jiatong and Jiangsu Nantong are the backbone enterprises. Single-layer heat shrinkable packaging film can be widely used in the packaging of fast food pasta, ceramic products, tea sets, mechanical parts, military machinery, hardware tools, construction and transportation materials. Multi-layer heat shrinkable film is mainly used for food packaging such as fresh meat, as well as packaging for daily necessities, medicine and health products, and stationery. It is suspected that the market demand for heat shrinkable packaging film in China will increase by 20% in the next five years.
2, wrapping film
The wrapping film has self-adhesiveness, does not need heat treatment in the packaging process, saves energy, reduces packaging cost, and can wrap the goods as a whole, which is convenient for loading and unloading and saves transportation cost. Wrap-wrapped film is generally made of linear low-density polyethylene. Domestically, an ethylene/butene copolymer having a melt index of 1-2 and a density of 0.98 g/cm3 is used in a single layer or by blow molding or casting. Produced on a three-layer coextrusion equipment. The key to making the wrap-wrapped film self-adhesive is to add chemical additives such as compatibilizers, adhesion promoters, etc. to two or more mutually compatible, partially compatible or incompatible resins. Or directly into the adhesive resin such as PIB. In addition to its packaging function, the wrap-wrapped film has some special functions. For example, the forage wrap packaging film for grass silage can maintain the moisture and nutrients of the pasture to facilitate the absorption of nutrients by the livestock, thereby promoting animal husbandry. development of. The domestic research and development of forage wrapping film began in 1997 with the cooperation of Light Industry Plastics Application Technology Research Institute and Beijing Company in Beijing Light Industry Institute (now Beijing Technology and Business University), which has been successfully applied and applied.
3, food aseptic packaging film
Food aseptic packaging film refers to ultra-high temperature food packaging film that can withstand the instant sterilization of foods (such as dairy products, beverages, seasonings), which can make food without preservatives, without It has a long shelf life in the case of cold hiding, which is a new technology and one of the development directions of plastic packaging. Aseptic packaging of food is divided into two types, one is a sterile large bag with a capacity of 5 ~ 1000L, the composite film of the bag is mainly made of PET aluminized film and PE film; the other is a sterile cup type For packaging, a PP/PE/EVa/PVDC/PS multi-layer co-extruded composite film is used, wherein PP is a protective layer film, EVA is a bonding layer, and PVDC is an oxygen barrier layer.
4, fruit and vegetable wrap film
Fruit and vegetable cling film is used for fruit and vegetable packaging to inhibit the metabolism and nutrient loss of fruits and vegetables during storage, and to maintain the flavor and quality of fruits and vegetables. China is the world's number one fruit and vegetable production and sales expense, and about 30% of fruits and vegetables are lost due to non-preservation during the transportation and transportation. Therefore, the preservation of fruits and vegetables in China has great economic value. At present, polyethylene film and polypropylene film are widely used in fresh-keeping packaging of fruits and vegetables. When selecting a suitable fresh-keeping packaging film, the gas permeability must be considered to maintain the proper oxygen and carbon dioxide concentration in the film, and a certain amount can be added. Porous materials (such as zeolite, azalea, etc.) to adsorb ethylene gas released by fruits.
5. Metallocene catalyzed polyolefin film
The polyolefin film prepared by metallocene single-center active catalysis has outstanding excellent properties, and currently mainly includes MPE, MPP, MPS and the like. The heat sealing performance, tensile property and puncture resistance of the film are superior to the traditional film, and can effectively solve the problems of penetration cracking, heat sealing cracking and the like in liquid packaging, and are mostly used for liquid packaging such as milk, soy sauce and shampoo. The heat seal layer of the composite film.
6, biaxially stretched film
Biaxially oriented films have always played an important role in film packaging, including biaxially oriented polypropylene (BOPP), biaxially oriented polyester (BOPET), biaxially stretched nylon (BOPa), etc., of which BOPP production is the largest. BOPP film is a new transparent packaging material developed in the 1960s. It has the advantages of light weight, non-toxic, odorless, moisture-proof, high mechanical properties, good dimensional stability and good printing. It can be widely used in food, candy, Packaging of cigarettes, tea, juice, milk, textiles, etc. The production method of the BOPP film includes a bubble tube method and a tenter method, and the tenter method is used more. In the method, the granular BOPP special material is extruded through a flat die, and after quenching on a cooling roll, and then preheating under different conditions, the longitudinal drawing and the horizontal pulling of the film are performed, so that the comprehensive performance of the film can be obtained. Great progress. BOPP's process technology has been developed with the continuous expansion of its application fields. For example, the co-extruded heat-sealed biaxially oriented polypropylene film produced by Nanjing Zhongda adopts the open hole positioning technology while maintaining the heat shrinkage of BOPP. The problem of heat sealability and adhesion of the middle strip film to the small strip film is solved. In China, the large demand for flexible packaging has provided a good market opportunity for the development of BOPP industry. However, since the end of the 1990s, the BOPP film industry has culminated in the cross-industry competition for the introduction of BOPP production line. It is expected that by the end of 2005, the national BOPP production capacity will be The breakthrough of 2 million tons, and the annual market demand is only about 900,000 tons, that is, there will be 1/2 of the production capacity to empty.
Among the biaxially stretched materials, the market share of BOPET and BOPa films follows the BOPP. Domestic BOPET film industry has also experienced overheated development and irrational investment. It is expected that the demand for BOPET in the domestic market will be 200,000 tons this year. By the end of this year, the domestic BOPET film production capacity will increase sharply to more than 500,000 tons. This situation of oversupply will be more serious; the production of BOPa film is optimistic, although there is still a certain market space, but if blindly introduce production lines, it may also lead to overcapacity.
7, CPP and CPE film
These two films were produced by a casting process by producing a non-stretched, non-oriented PP or PE cast film by casting a PP or PE melt. CPP and CPE films have excellent performance balance, and subsequent processes such as printing and lamination are extremely convenient, and are widely used in the packaging field, especially CPP has a large market. At present, China has introduced more than 60 CPP production lines with a total production capacity of over 150,000 tons. The domestic market of CPP film is mainly composed of film for composite packaging. The largest application amount is aluminized film and cooking film, such as the laser anti-counterfeiting film of Shanghai Zijiang Color Printing Co., Ltd., the breathable cast film of Zihua Company, and the resistance of Wisteria. Electrostatic CPP films are listed in the National Torch Project.
8. Barrier composite film
This is a functional film that has been widely used in the field of food packaging and medical packaging in China.
Dongguan C.Y. RedApple Industrial Limited , https://www.zjhpgbags.com