1. Development history of pre-coating film industry
The printed product and the film are combined by professional laminating equipment to form a paper-plastic product. This technology is called lamination. The coated printed matter has a brighter and smoother surface, a brighter pattern, abrasion resistance, bending resistance, tensile resistance, moisture resistance, chemical corrosion resistance and other properties have been enhanced, even some apparent defects in the printing process can be To a large extent, it is compensated, therefore, not only the service life is extended, but the aesthetics of the product is greatly improved. Since the filming technology was born in the 1950s, the filming technology has experienced three important development stages: solvent-based instant coating technology, water-soluble instant coating technology, and pre-coating technology.
(1) The revolution of packaging materials led to the birth of solvent-based instant coating technology
In the 1950s and 1960s, BOPET (biaxially oriented polyester), BOPP (biaxially oriented polypropylene), BOPA (biaxially oriented nylon) and other film products were born, which promoted the revolution of packaging materials in the world, thus driving the The birth of the instant coating technology for post-press coating. Among them, BOPP film has played a vital role in this revolution due to its reasonable price and wide application.
BOPP film was invented by Montecati, Italy in 1958, and it was industrialized in 1962, and then it has developed rapidly all over the world. BOPP film has the advantages of light weight, non-toxic, odorless, moisture-proof, high mechanical strength, dimensional stability, good printing performance, good transparency, reasonable price, low pollution, etc. It also reduces the use of paper packaging and strengthens the The protection of forest resources and the birth of BOPP film quickly led to the transformation of the packaging material industry and began to be widely used in the packaging of food, medicine, and daily necessities.
With the rapid development of the packaging industry, solvent-based instant coating technology
(SolventLaminatingTechnology) was also invented in the United States in the late 1950s, and entered China in the late 1960s. It still occupies a leading position in my country's laminating market. The solvent-based instant coating technology uses a dedicated instant coating film equipment to coat the solvent-based instant coating glue blended with a benzene solvent on the film, and then is dried, heated and pressurized to compound with the printed product. The coated packaging has a brighter and smoother surface, more vivid patterns, abrasion resistance, folding resistance, tensile resistance, moisture resistance, and chemical corrosion resistance, so that the instant coating technology can be quickly promoted.
(2) Increased environmental protection requirements in developed countries have driven the development of water-based instant coating technology
After entering the 1970s, developed countries have gradually increased their awareness and governance of environmental protection. The solvent-based instant coating technology will cause serious damage to the health of producers and consumers due to the benzene solvent used, which can easily lead to leukemia and infertility. At the same time, organic solvents also have potential fire hazards in processing workshops, and developed countries are paying more and more attention to their hazards. In order to solve the above-mentioned pollution problem, water-based instant coating technology emerged in the late 1970s in European and American countries.
The water-based instant coating technology is based on the original solvent-based instant coating technology, replacing the organic solvent glue with a non-toxic and harmless water-based adhesive (ie water-based acrylate adhesive) to solve the pollution problem of the solvent-based instant coating technology . Due to its environmental advantages compared with solvent-based instant coating technology, it was quickly promoted and entered China in the mid-1990s. It still holds about 35% market share in the European market.
(3) Increased environmental protection requirements and the printing industry revolution promoted the birth and development of pre-coating technology
Although the water-based instant coating process solves the benzene pollution problem of solvent-based instant coating, it has the pollution problem that requires a large amount of water to clean and discharge the cleaning sewage. It is still not an ideal environmentally friendly coating solution. At the same time, it is in product quality and There are still certain defects in production efficiency.
In the 1980s, with the birth of laser phototypesetting and offset printing technology, the printing industry ushered in a revolution, from then on to the era of high-speed (increased from 2,000 prints/hour to 18,000 prints/hour), automation, and information technology. In addition, the post-press processing requirements are more exquisite, and the market demand for printed product orders has also shifted from the original long version (that is, single variety, large batch, long time) to short version (multiple varieties, small batches, fast and even 24-hour delivery).
Due to its own technical bottlenecks, the traditional instant coating technology has been difficult to adapt to the requirements of the development of printing technology: First, the instant coating technology has low film coating efficiency. As the laminating process requires gluing, drying and other links, the laminating speed is limited, only 15-30 meters per minute, which is far from meeting the post-press processing requirements after high-speed printing. Secondly, the quality is low. Instant coating technology is easy to cause blistering, wrinkle problems, gray color, paper deformation, and discoloration of graphics and text. Thirdly, the emergence of digital printing technology puts forward new requirements for laminating, namely coating technology cannot be used for digital printing, only pre-coating technology can be used.
In 1989, the American GBC company complied with the needs of printing technology change, after years of research, successfully developed the pre-coating technology, which created a new era of post-press coating technology.
The pre-coated film is a non-toxic and harmless hot melt adhesive layer suitable for the material to be laminated, through a special process, and a film substrate that meets the corresponding technical requirements. The production process is that the pre-coated film manufacturer will meet the specific technical requirements of film materials, such as BOPP, BOPET, etc., through special equipment for electrical treatment, heating, and pressure treatment, and then through the extruder through high temperature and high pressure to produce The hot melt adhesive is compounded into semi-finished products, and then according to the customer's product size requirements, the slitting machine is processed into a finished product that meets the size requirements of printing and packaging film products. Printing and packaging companies do not need to do any gluing process on the film during the process of laminating the printed product, only need to heat and press the special laminating machine, and the operation process is simple and pollution-free.
The unique production technology and laminating process of the pre-coated film make it environmentally friendly, capable of high-speed laminating (60-100 m/min), high laminating quality, high bonding strength, exquisite post-printing, and good processing performance after laminating, etc. Advantages, so once launched, it has been quickly promoted in the United States. The United States realized the full replacement of pre-coating technology to instant-coating technology in 1996, and currently accounts for about 95% of the laminating market. Since Europe is the birthplace of water-based instant coating technology, the promotion of pre-coating film was slow at first, but in recent years the market share of pre-coating technology has gradually increased steadily, and it has now reached 65%. Japan and South Korea began to promote pre-coated films in the 1990s, and they have reached approximately 70% and 50% of the market share. 1 At the same time, the birth of pre-coated films made it possible to laminate digital printing products, which gave birth to the emerging market segment of commercial printing laminates.
In the printing industry revolution, not only the pre-coating film was born, but also some other post-press surface modification processing technologies also developed, including the UV coating technology that is currently widely used. UV coating refers to a kind of printing formed by applying a special special coating agent to the performance or local area of the printed matter precisely and evenly, and then irradiating it with ultraviolet rays to dry and harden the coating agent on the surface of the printed matter at a very fast speed. Post-processing technology. UV coating technology can be used to modify the entire surface of the printed product, and it can also be used for partial UV coating treatment on the printed product after coating to achieve special artistic effects. UV coating technology can play a certain role in protecting and enhancing printed products. However, there is no composite process between UV coating and the film, and the wear resistance and folding resistance are poor. Although it can bring good appearance effects, it can protect the printed product, extend the service life, and reprocess the film after coating. Incompetent. At the same time, the printed product after UV coating is not conducive to further post-processing (such as indentation, embossing, hot stamping, etc.) on its surface. Therefore, the exquisiteness and artistic effect of the printed product are also affected and restricted. Therefore, UV coating is generally used for short-term reading and simple packaging, and the space in the high-end printing market is relatively limited.
The technology of pre-coating film has been mastered by developed countries since its invention. In 1998, the issuer’s controlling shareholder Beijing Kangde Electromechanical Development Corporation (now known as "Kangde Group") started the research and development of this technology and was approved by the former State Economic and Trade Commission. Included in the 2000 National Key Technological Innovation Project Plan for support. After four years of hard work, through independent research and development combined with technical cooperation, the issuer has mastered the pre-coating film production technology with independent intellectual property rights, and on October 16, 2002, China's first pre-coating film production line was completed and put into production. In recent years, with the increase of national environmental protection awareness, the market demand brought by the improvement of national printing technology and quality requirements, and the promotion of relevant policies gradually introduced by the country, my country's pre-coated film industry has made great progress.
2. Classification of pre-coated film products
According to the base material, the pre-coated film can be divided into BOPP pre-coated film, BOPET pre-coated film and BOPA pre-coated film. For details about BOPP pre-coated film and BOPET pre-coated film, please refer to "I. (2) Main Products" in this section. BOPA pre-coated film is a pre-coated film produced with BOPA film (or biaxially oriented nylon film) as the substrate. It has good barrier properties, puncture resistance, impact resistance, high brightness, good heat sealability and Hygroscopicity and printability can meet the requirements of some high-end customers for products after filming.
According to the market application, it can be divided into industrial printing pre-coating film, commercial printing pre-coating film and special-purpose pre-coating film. The industrial printing market mainly refers to the laminating market for publications, printed matter and consumer product packaging such as food, medicine, daily necessities, etc.; the commercial printing market mainly refers to the application laminating market in emerging fields such as index code printing, card card, anti-counterfeiting, and commercial advertising; special-purpose markets Mainly refers to building materials. The latter two types of markets are emerging markets that have been spawned with the emergence and development of pre-coating technology.
European, American, Japanese, and Korean companies represented by GBC have been in a dominant position in the international market, especially in the high-end market due to their early start and relatively mature technology. However, in recent years, the Chinese pre-coating film industry represented by issuers and the Indian pre-coating film industry represented by COSMO have risen rapidly due to their lower product prices and product quality levels close to GBC and other companies. At present, the world pre-coating film industry Already moving to Asia.
Analysis of the status quo of upstream industry development
The main raw materials of the pre-coated film manufacturing industry are BOPP film, EVA hot melt adhesive, BOPET film, and LDPE hot melt adhesive. The current development status of the industry is as follows:
1. Current status of BOPP industry
BOPP film (or biaxially oriented polypropylene film) is prepared by co-extrusion of polypropylene particles into a sheet, and then stretched in both vertical and horizontal directions. It is used as a base in the production of BOPP pre-coated film. material. BOPP film is light weight, non-toxic, odorless, physical stability, mechanical strength, air tightness, high transparency and gloss, good printing performance, simple production process, low pollution, reasonable price, and it is widely used Packaging and printing of food, medicine, daily light industry, clothing, cigarettes and other products.
2, EVA industry status
EVA is a solid meltable copolymer composed of ethylene (E) and vinyl acetate (VA). The higher the content of vinyl acetate (VA content), the greater the transparency, softness and toughness. Higher, and lower melting point. According to different VA content, EVA products can be divided into foaming grade, wire and cable grade, coating grade, hot melt grade and other different grades. The application fields involve packaging, adhesives, printing, wire and cable, footwear and clothing. In the production of pre-coated film, coating-grade EVA is a commonly used hot-melt adhesive, which is compounded with the substrate in the process of heating and pressing to become a pre-coated product.
3, BOPET industry status
BOPET film (or polyester film) is made of polyester (ie polyethylene terephthalate) as a raw material, which is made into thick sheets by extrusion, and then biaxially stretched. Used as a substrate in coating film production. BOPET film is a colorless, transparent, glossy film with excellent mechanical properties, high rigidity, hardness and toughness, puncture resistance, friction resistance, high and low temperature resistance, chemical resistance, oil resistance, air tightness and fragrance retention It has good performance and is one of the commonly used barrier composite film substrates.
4, LDPE industry status
LDPE (ie low-density polyethylene) is a thermoplastic obtained by free radical polymerization of ethylene under high pressure. Due to its good flexibility, impact resistance, airtightness, electrical insulation, chemical stability and molding processability, LDPE is widely used Used in various polymer processing technologies, the main purpose is to produce film products, including agricultural films, packaging films, and industrial and construction films. In addition, in the production of pre-coating film, LDPE is used as a hot melt adhesive for BOPET pre-coating film.
As a polyethylene product that has been used earlier, the production process of LDPE has been very mature. At present, large foreign chemical companies, such as BASF, Japan's Sumitomo, and South Korea's LG, as well as domestic petrochemical companies, such as Shanghai Petrochemical and Yangzi Petrochemical, can provide a stable supply of LDPE to the domestic market. At the same time, because it is a downstream product of petroleum processing, similar to EVA, the price trend of LDPE is greatly affected by the fluctuation of crude oil prices.
The main factors affecting the profit level of the pre-coating film industry are:
First, changes in raw materials and product prices. Both have a very close relationship with crude oil prices, and changes in crude oil prices will be transmitted downstream along the industrial chain. However, what is more favorable to the pre-coating film industry is that the pre-coating film accounts for a small proportion of the total cost of downstream products, and downstream users have lower demand elasticity, even if the pre-coating film manufacturers are affected by the increase in the price of upstream raw materials. Increasing prices, downstream printing companies and distributors will not reduce the amount of pre-coating film purchases for this reason, pre-coating film manufacturers can effectively transfer cost pressure to the downstream, thereby ensuring their own profit margins. On the other hand, the upstream raw materials of the pre-coating film are in a state of oversupply, which is a fully competitive market. The pre-coating film companies have strong bargaining power with the low-end raw material suppliers.
Second, technological progress. Generally, leading pre-coating film companies can reduce production costs and increase profit margins by developing new technologies. However, when advanced technologies are gradually mastered by most companies, the level of profitability will return to equalization.