Development direction of the hottest precomposite

The development direction of pre composite film

single layer plastic film cannot meet the requirements of the development of packaging technology due to the limitations of performance. At present, various composite films are widely used in the market, that is, they are made from a substrate such as BOPP, nylon, popet, cellophane, etc. after printing, and then compounded with one or more layers of films. The processing technology of the whole composite film is completed by the plastic color printing factory. At present, there are many shortcomings, such as complex process, many processes, large loss, large equipment investment, large environmental pollution, poor health indicators and so on. Experts from developed countries in the world are carrying out a revolution in composite film processing technology in response to these situations. These uses will make the aircraft lighter and its interior more exciting, and have achieved gratifying results. The so-called pre composite film means that the composite material itself has been processed after completion in the composite color printing factory, as long as it is printed, polished, cut, etc. Now let's explain some pre composite packaging materials on the market

first, start with the sealing material

the inner layer of the composite film is basically a composite polyolefin material, which has heat sealing performance. However, the packaging of many goods does not need such a large sealing strength. In the foreign market, there is a kind of hot melt adhesive that needs to be "printed" on the inner side of the composite film. For example, 40u bopp/printing + hot sealing is coated with hot melt adhesive

second, another method is to produce a material that can be thermally compounded

for example: bopp/pre coated with heat sealing adhesive or heat sealing layer. Printed on BOPP or pet in the printing plant, the post-processing can be carried out directly without curing by heating roller lamination

III. "cold sealing" after conversion from hot sealing

due to the high speed of small packaging requirements for some goods, and can not be heated, such as chocolate packaging. A kind of composite film developed abroad that can be cold sealed. It is understood that it is also processed in the printing plant. The sealing layer of the inner layer is similar to a kind of self-adhesive, but it has no viscosity of general self-adhesive

the finished products can be sealed by adding some pressure to the sealing place on the high-speed packaging machine, which can greatly improve the home decoration speed of the relatively large experimental machine factory of Baoji Jinan new era Gold Testing Instrument Co., Ltd

IV. precoating process of composite film

in order to reduce the investment of various plastic composite factories, recently, the film substrate factory has developed a preproduct of composite film coating. The author estimates that it can be mass produced in the future when the outer layer is not titanium alloy sleeve for a long time

the production of these composite film precoats is generally completed in the factory producing the substrate. The final processing of the composite film is completed in the color printing factory, and there is no need for composite equipment. As long as there is a printing machine, the final work of the composite film can be completed. The key is to add brightener, anti friction agent, temperature resistant agent, anti electrostatic agent, fog agent, etc. on the printing machine according to the requirements of users after printing. There have been some experiments in some places. For example, the commonly used product pet12 U/printing/aluminum foil/modified polyolefin can be used for fruit milk capping film. Using aluminum foil/coating material to print on the surface of aluminum foil and then print a layer of temperature resistant brightener can save cost and improve the stability of products

v. finally, composite films with high sealing strength are needed, which also starts with sealing materials

at present, the inner sealing film with high heat sealing strength tends to develop special materials with thin thickness and high strength. In this regard, there are many reports from relevant manufacturers, such as high temperature resistant, cooking resistant polypropylene, metallocene polyolefin particles, acrylic modified polymers, ionic resins, etc., which will not be repeated here. It has developed abroad and is just starting at home. If it wants to develop, it needs the joint efforts of color printing plants, film substrate plants, ink, adhesives and other raw and auxiliary material plants to communicate with each other in order to succeed. At present, domestic manufacturers that have produced coextrusion multilayer films have provided good opportunities, especially some factories that produce narrow width films, because they can't compare with those high-speed and wide width large enterprises. It is a good project to research and develop the production of various multifunctional pre composite films

VI. the development of some foreign factories can be used as a reference for some domestic film factories

during my technical investigation in the United States, I found that QPF company, formerly named in Chicago, is a professional factory producing narrow BOPP films. In order to survive, it specially develops energetic Azolla films, the most prominent of which is a BOPP vacuum aluminized film with high heat sealing strength

among them, EVA film is made in the film blowing machine. The EVA film is extruded in the BOPP production process, and then pasted on the part after longitudinal stretching. Then it is sent to the horizontal stretching device for transverse stretching to make BOPP film with high heat sealing strength. Then it is vacuum aluminized, and finally the heat sealable vacuum aluminized BOPP film is completed. I think this is a typical pre composite film

VII. Summary

in general, the pre composite film has a wide development prospect, especially China's energy shortage. At present, the production process of composite plastic packaging film is processed in a plastic printing plant, and the waste edge loss is too large, which has a great impact on environmental pollution and the sanitary performance of packaging materials. It is suggested that relevant associations should organize relevant manufacturers to discuss this issue, so that China's pre composite films can have a greater development

source: plastic packaging information center