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Production process of multilayer co-extruded film

Jan 03, 2017

Now, with the industrial upgrading many domestic industries, boosting the multilayer co-extruded film in domestic demand, many companies have or are ready to launch this project. Due to the different understanding of such products, each with its own awareness and understanding of the extent of the recipe. For the recipe varies, Temporary rational woman and she said, the state of the public that goes. Therefore, I recommend yourself some cases have been conducted to understand an objective, impartial analysis, for your reference.


Some time ago, a friend to consult the author, how the electronics industry for the production of packaging bag with nylon film. And they commissioned some domestic factories do some demos, from the results of the test have been analyzed, the thickness of the wire 12 can not meet their requirements. Structure of PA / TIE / LLDPE / TIE / modified PE, wherein the nylon content of 20%. Tests, with a ballpoint pen poke.


I think, first of all, the test mode is not desirable. Testing should take a scientific attitude, with the right approach, so test it out data that has the authenticity, refer to the process can be improved styling and; secondly, to analyze the structure, the structure is feasible, applicable areas of the product may have errors;Third, the author's friend did not explain the real situation to the author, so that the author of the problem is not known. Therefore, I can not be the correct answer.


The author of this friend's problem very representative of the current domestic production processes for the recipe structure and prospects of nylon film, various opinions, after a seven-layer barrier film, said to be replaced, how how bad the structure and so on. Some say that the CPP would like BOPP, BOPET industry, and finally we Rush costs and market prices, the results will suffer. Everyone no favors. I believe that, in terms of what kind of view, if focusing on the technical aspects of keeping, so the competition in the market can maintain the core competitiveness of enterprises. Therefore, the author of many years of experience on some of the information collected over the years to be screened comb. The judge made the following analysis:


First, the structural design


1, casting process, PE / TIE / PA / TIE / PE-based design advantage of this construction is that, to ensure the flatness of the film, and a film using the overall function is not destroyed (nylon hygroscopic), less prone to curling; mainly in Guangdong Zhongshan Xiang Fu and Changzhou sea enterprises and other enterprises in the use of the casting process, represented


2. Blown process, (1) the blowing, PA / TIE / PA / TIE / PE, lead author of the research structure should be designed by the Dalian Sun proposed work, this film is mainly to eliminate the film during cooling reduce the crystallinity of the problem, so you can achieve good transparency, to make up for the shortcomings air cooling (cooling is not sufficient and fast). (2) blowing, PA / TIE / PE / TIE / LLDPE (EVA) and PE / TIE / PA / TIE / PE two kinds, since the lower blowing cooling casting in a similar way, and therefore, the structure in the early design in the use of the casting method with the same structure, the latter especially in recent years, factories began using PA / TIE / PE / TIE / LLDPE (EVA) structure for production.


I believe that, no matter what kind of craft production method, should be considered in the structural design is reasonable, there is no absolute good and bad points. In other words, whether or not in line with customer requirements, structural design as simple as possible, should not buy in order to improve or prevent competitors from copying the design is too complex, it might have its own self-inflicted in the production process and quality control trouble.


Second, the material selection


1, nylon material, nylon material currently used in the production of the film at the imported materials, the main suppliers have DSM, BASF, DUPONT, Mitsui, Toray, Mitsubishi, etc., to BASF, DUPONT, DSM's feed use most.



2, TIE (adhesive resin), the current data collected from the author showed that the 30E671 DUPONT use most. Of course, there is also an alternative to other brands of products, such as SK's LE350V, and Guangdong Lushan's products.


3, PE material, due to the higher grades of PE products, columns, only the author's preferences, for your reference.Such cooperation in the blowing method can increase flexibility and dimensional stability of the film. While the transparency is also improved.


To ensure that the design options other than the above is correct, you should also consider the issue in the mechanical design parameters in the production process, such as an extruder temperature setting, I believe that the temperature difference between the district heating temperature should not exceed 10 degrees, so you can ensure the material layers.The temperature difference is too large will not influence each other, resulting in trouble in the extrusion and cooling process, in order to have uneven thickness, streaking problems.


In addition, beyond these purely technical problem, I think, in the production process of the formulation process, production costs should be, as well as material loss problem considered together, so you can ensure market acceptance of the product, not to make their products in market by the impact of competitors!