The hottest solvent-free composite is about to ush

Solvent free compounding is about to usher in an era of great development

interview with Zuo Guangshen, general manager of Tongze Machinery Co., Ltd.

plastic composite flexible packaging has become an indispensable packaging material in people's life. However, so far, in China, composite flexible packaging materials are basically produced by solvent based dry composite process, which has serious problems in energy consumption, environmental protection, health and many other aspects. At present, although domestic manufacturers have greatly improved the use of dry compounding to produce composite flexible packaging materials through the development and application of new green packaging additives such as alcohol soluble adhesives and water-based adhesives, which has played a positive role in promoting the development of green packaging, the inherent shortcomings of dry compounding process itself have not changed fundamentally. The solution of solvent residue has always made flexible packaging face two choices: temporary and permanent cure. Cure symptoms and control solvent residue: solvent based dry compounding (10mg/m2 5mg/m2 1.5mg/m2) is adopted, but it is still difficult to solve the other two major problems: pollution and safety. Thoroughly eliminate solvent residue: use solvent-free compounding instead of dry compounding. But in the past many years, we still revolved around in the frame of treating symptoms

in today's sustainable development, it is a very urgent task for practitioners to put people first and vigorously advocate a green packaging process solvent-free composite process with significant resource conservation, superior environmental protection performance and strong reliability of product hygiene performance. For this purpose, Zuo Guangshen, general manager of Guangzhou Tongze Machinery Co., Ltd., was specially interviewed, and he was asked to introduce the solvent-free composite technology and equipment at home and abroad

there is a large gap between domestic and foreign markets

Zuo Guangshen first introduced the development status of solvent-free composite technology. Solvent free compounding technology is one of the three most important environmental protection technologies of contemporary international flexible packaging (solvent-free compounding technology, flexographic printing and coextrusion compounding), and it is the most undisputed environmental protection technology. The main advantages are: a typical "three no" process, that is, the whole process of production and use is pollution-free; The finished product (composite material) has no solvent residue; Due to the non use of solvents, there is no explosion in the production process, etc., the national power battery innovation center has been established. In addition, the energy consumption of drying (curing) is very low, which is only 1/25 1/15 of that of dry compounding, and the use cost is low. Fully meet the requirements of environmental protection, health and safety (EHS). Using solvent-free compounding technology to replace dry compounding not only shows obvious advantages in environmental protection, production safety and ensuring product quality, but also has remarkable effects in reducing production costs and improving economic benefits. It represents one of the development directions of composite technology

at present, the current situation of solvent-free compounding technology abroad is that it originated in the 1970s (Germany), and its rapid development began in the 1980s, accounting for 80% - 90% of the new compounding machine equipment (Europe, the United States). (3) due to the heat blocking effect of top, attention was paid to it in the late 1990s, and it has developed rapidly. The current situation of solvent-free composite technology in China is that it began in the middle and late 1990s and has been developing slowly, and has developed slightly faster in recent years. The number of existing installations is no more than 40 (accounting for no more than 2% of the total number of compound machines), which is far lower than that in developed countries

many factors restrict the development of technology

when talking about the reasons for the slow promotion of solvent-free compounding in China, President Zuo said that there are many reasons in this regard, but the main reasons are: first, the pressure and motivation of domestic enterprises are not enough. For a long time, the attention of Chinese people to health and the requirements of the government and the market for environmental protection and safety have not posed enough pressure or promotion on packaging and printing enterprises. Second, long-term propaganda is misleading. For a long time, many propaganda and public opinion have described solvent-free compounding as a simple, easy to control process suitable for all substrates, but in fact, it is a process technology with simple principle but difficult to grasp, and it is not suitable for compounding of all materials. Therefore, almost all enterprises have insufficient expectations of the difficulty of this technology promotion at the initial stage. Third, there are few successful early users. It has been more than 10 years since China began to introduce this technology, but almost all manufacturers have experienced many twists and turns in the process of using it. There is no plain sailing. At present, many equipment has not entered the normal use state, resulting in a large number of latecomers to respect this technology or stay at a standstill, forming a typical situation of not being popular. Fourth, the characteristics of the process itself are complex. This process technology is quite different from the dry composite process widely used now, and there is not enough mature experience to learn from. Foreign experience cannot be directly applied, and domestic enterprises need to make arduous efforts to explore their own

environmental protection challenges promote industrial upgrading

but at present, the most important development trend of international flexible packaging is EHS (environmental protection, health and safety), which has been widely recognized in China. The national supervision of food safety has been significantly strengthened. For example, QS certification is an important national measure, and Chinese people's attention to health and safety has also significantly increased; In particular, the newly revised hygienic standard for the use of additives for food containers and packaging materials (GB9685-2008) will be issued, especially for the use of solvents in adhesives and inks

in this regard, President Zuo also agreed that the promotion of solvent-free composite in China has some new favorable conditions, which has injected new impetus into the promotion of solvent-free composite. The development of domestic equipment and adhesives has made qualitative progress, providing favorable conditions for promotion. In particular, the SSL series solvent-free laminating machine newly developed by Guangzhou Tongze Machinery Co., Ltd. occupies a leading position in China, has reached the advanced level of similar foreign products, and fully meets the technical conditions after adjustment of hardness tester, which is widely promoted in China. In particular, Tongze's Sany promotion plan for solvent-free compounding will provide a strong guarantee for domestic enterprises to adopt solvent-free compounding technology. Tongze company takes solvent-free compounding equipment technology as its main product for two reasons: first, it has determined the product direction as environmental protection equipment and technology from the beginning. Solvent-free compounding is just one of such technologies and has been paid attention to in China; Second, as a new enterprise, we hope to carry out product research and development and market promotion in a professional way at a starting point that domestic peers have not yet reached, so as to avoid repeating the path of others. In addition, the gap between domestic equipment has been large, and the market demand has increased significantly in recent years, which is also an important reason

independent innovation promotes development

when talking about the solvent-free composite Sany promotion plan, President Zuo said that Chinese enterprises adopt solvent-free composite technology. From the operational level, there are three main difficulties: equipment difficulty, process difficulty and captain difficulty

equipment difficulty includes two meanings: the price of imported equipment is high, which is difficult for most enterprises to buy; The equipment is highly required and difficult to manufacture. At present, the import of a set of equipment requires about 2.5 million yuan to 4 million yuan (excluding tax), which is difficult for many enterprises to purchase. Therefore, there are great constraints on the large-scale promotion of this technology. On the other hand, it is difficult to manufacture solvent-free compounding machine. Due to the high requirements of coating mechanism and tension system, high machine speed (250 m/min ~ 300 m/min) and high safety requirements, it is impossible to obtain equipment that meets the use requirements by the traditional method of manufacturing drying machine (speed 100 m/min ~ 150 m/min). From experience, solvent-free compounding machine needs new technical specifications and manufacturing methods, and the threshold is obviously higher than that of dry compounding machine

process difficulty refers to the difficulty in matching the equipment, substrate, adhesive and process parameters of solvent-free compounding. The main reasons are: first, it is difficult to control the tension, because the initial adhesion is very low, and the setting control of the tension of each section is very strict. Second, it is difficult to control the coating amount, mainly because there are many control parameters (6 ~ 7), and the relationship between the coating amount and some parameters is sensitive. Third, due to the need to cause sheet metal corrosion curing time, the composite results appear to lag behind. Fourth, because the production speed is generally high, the overall control of the production process is more difficult. Therefore, the difficulty of process control and the risk of waste products have increased significantly

captain difficulty has two meanings, one is that it is difficult to find a qualified captain, and the other is that it is difficult to cultivate a qualified captain. At present, there is a great shortage of qualified captain or supervisor for solvent-free compounding in China. In China, it is not difficult to find the captain and supervisor of 10000 drying and restoring machines, but it is very difficult to find 100 qualified solventless recombiner captains. Secondly, it is more difficult to cultivate a qualified solventless recombiner than a dryer captain in the long run, because such a captain not only requires sufficient operating experience, but also needs higher theoretical basis and multidisciplinary knowledge, and cannot adopt the traditional training mode

general manager Zuo said that in view of the current situation of solvent-free compounding in China, especially the above three difficulties (i.e. equipment difficulty, process difficulty and captain difficulty), a solvent-free compounding technology promotion and training plan, called the Trinity program, refers to providing customers with a set of equipment, a set of process and a captain training plan. These three contents form an organic whole. The specific contents are as follows: a set of equipment, a series of solvent-free laminating machines launched by Tongze company after a long time of research and development, will become the standard laminating machine for flexible packaging. At present, it has two models, ssl1300 and ssl1000. The main features are: accurate coating amount control; High composite quality; Highly humanized; The machine is safe, stable and reliable; Easy to operate and use. The reason for these features is that when designing this series of models, all key parts have been deeply studied and a number of patented technologies have been adopted. Of course, we have also adopted many quality assurance measures in the processing and assembly engineering. According to the on-site demonstration, the machine still runs very smoothly at the speed of 320 m/min, and the coating amount reaches about 1.4 g/m2, which is not inferior to the imported equipment. Including SSL series solvent-free compounding machine and supporting equipment and tools (glue mixer, heater, refrigerator, exhaust fan, tools, etc.), i.e. 1 + 5 scheme. Appropriate manufacturers of supporting equipment and tools will be selected to form a supplier team for domestic and foreign markets

a set of processes refers to the general process procedures and parameter determination methods that can produce qualified products for different composite substrates and the process parameters of a typical product. We promise: before ordering the equipment, we can trial produce a product sample that meets the use requirements for a fee; Before the equipment leaves the factory, a product sample meeting the use requirements (including its main production process parameters) can be provided free of charge

a captain training course is a course to train qualified pilots or supervisors. Through theoretical learning, computer operation and other links, a large number of pilots and supervisors who have certain theories and can operate more skillfully are trained. The training course of solvent-free compounding technology includes chapters such as the principle of solvent-free compounding process, the structure and adjustment of solvent-free compounding machine, the performance and application of adhesive, etc. The tutorial focuses on application, but also introduces theory, and the preparation will be completed soon. We will cooperate with gravure printing branch of China Printing Association and use the strength of cooperative enterprises to run training courses well. The goal is to train a large number of captains and supervisors who have certain theories and can operate skillfully, and strive to achieve a solvent-free recombiner at least