Shrink film for packaging: description and types

As technology develops in the chemical industry, the products are also being improved. A significant segment of the industry is packaging materials, with which manufacturers of non-food products and foodstuffs retain their properties and performance. Shrink film for packaging, photo of which is presented below, has become very popular.

Features of shrink film

The main difference between the shrink film is the ability to shrink to the size corresponding to the target object. Its compression occurs under the influence of high temperatures. After cooling, the material takes on the shape of the product to be packed. Thus, shrink film for packaging allows you to maintain the technical and physical qualities of various products, including construction and food.

Depending on the scope of use, manufacturers also provide some features in the film. For example, perforated film is produced for bakery products. The basis for the raw material is polyvinyl chloride or polyolefin granules. If PVC is traditionally in demand due to its strength, then the PF is advantageous in that it has no harmful impurities. As a rule, a shrink film for packing bottles or food containers is produced precisely from polyolefin raw materials.

Application of the film

Depending on shrinkage and thickness, the film can be used for a variety of purposes. So, if we are talking about a small degree of clamping, then the material can be used to work with soft tissue products, printed products or food products. And on the contrary, rigid shrinkage allows to serve heavy building materials, as well as products with non-standard forms. These include a shrink film for packing lumber, which covers group batches, securely fixing them during transportation. By the way, polyvinyl chloride is used to make such a film. It is important to note that in addition to protective and filling functions, the film can be used for visual design of products. Shrink wrapping is often wrapped around wallpaper, toys, magazines, giving products extra gloss and shine.

Material specifications

The film is supplied in different formats, the choice of which depends on the packaging machine. With regard to the choice for specific products, then pay attention to two characteristics - the percentage of shrinkage and thickness. As a rule, the percentage of shrinkage in the longitudinal line is about 60-70%, and in the cross section - from 10 to 50%. The strength of the package affects the thickness. The thinnest shrink film for packaging, made according to the standards of the technological process, has a thickness of 10 microns. High-strength variations can have up to 200 μm. In addition, it is worth considering the temperature regime at which the material can be used. On average, the permissible temperature range is -40 to +50 ° C, although depending on the application, technologists can add additives that extend this range.

Operational properties

There is a basic set of qualities that practically all modifications of shrink films possess. First of all, this is a high mechanical strength, which determines the protective qualities of the packaging. Also, this type of material is distinguished by a combination of elasticity and transparency. Resistance to the formation of water condensation and moisture resistance also expand the possibilities for using this film.

Of course, the almost unique property that a shrink film has for packaging is the ability to change linear parameters and obtain the shape of the target product. Another thing is that for this you need special equipment that realizes the packing. But in the future, a dense and compact fit will give two significant advantages. First, it will provide protection from opening, and secondly, in the process of transportation, lots with goods will occupy a minimum of space. If we talk about certain properties, then among them we can note the ecological safety and attractiveness of the appearance. These qualities are applicable to special modifications of the film product.

Varieties

Although outwardly most of the film materials with the possibility of heat shrinkage look the same, they have many differences. Technologists classify packaging according to the type of structure, rigidity, the presence of certain modifiers in the composition, dimensions, forms of production, etc. One of the most significant features of the separation is the type of structure. The cross-cut film fabric is considered to be the most convenient for use. It does not set records in terms of strength, but in its structure the optimum balance of web thickness and tensile strength is observed. This property is important if, for example, a shrink film is used to pack the lining in large volumes. Before serving employees in this case is the task of maximizing the storage of free space and at the same time ensuring the integrity of the film itself. As for the differences in the composition, the materials that contain the hydrochloride of rubber, polystyrene, polyamide, etc., are singled out. The classification by the number of film layers deserves special attention.

Multilayer and single-layer film

First of all, it should be noted that the basic differences are determined by the manufacturing method. Single-layer fabric is produced by the method of extrusion, that is, by punching plastic mass. Advantages of the products obtained in this way include increased viscosity, elasticity and transparency. But if you choose a shrink film for packing bricks or other building materials, it is better to turn to multi-layered analogues. Such material is produced using the coextrusion technique. The main difference between the manufacturing process is that special heads of the extruders are used. The multi-layer web includes a copolymer and a modifying acid, as well as an ethylene copolymer. The structure of the film may include several additional layers.

Packing configurations

There are different options for packaging the goods in shrink film, the choice of which is determined by the characteristics of the product. In particular, single, group and stacked packaging is used. The first option is used to work with piece goods - this is the so-called individual packaging. The group method is used for a single set of several products with the same dimensional characteristics. For example, this configuration allows the realization of a shrink film for pallet packaging, which is pre-stacked on a special substrate. In addition to storage, this method of packaging enables safe and safe transportation of products. The stacking configuration also provides for the use of a pallet, but with improved stiffness indicators. This option is suitable for servicing a wide range of products: from cans and books to bricks and sacks. After stacking the product is covered with a film cover.

Form of issue and marking

The produced film is wound on special bushings and is supplied in the form of rolls. On top, each winding is also covered with a protective sheath made of paper or the same polyethylene. As a rule, the shrink film for roll packaging has a width of up to 500 mm and weighs 35 kg. But in industry and production of construction materials, other formats are also used, for example, with a width of more than 1000 mm and a mass of up to 50 kg. Each roll is necessarily labeled with a label containing information about the manufacturer, product parameters, date of issue, etc. When choosing a film product, you should also receive information about the tests - knowledge of the operational properties and capabilities will help you to purchase the most suitable packaging for specific needs.

Conclusion

The market for packaging products is quite wide, which is due to the huge demand for the goods of this group. Quality packaging is required today in various areas: from the food industry to retail outlets. As practice shows the use of shrink material, about 90% of this product is used in the maintenance of non-food products. However, the increase in ecological safety extends the possibilities of using packaging for vegetables, bakery products, semi-finished products, etc.

The shrink film is being improved for packing goods and in terms of strength. Rigidity, tear resistance and tightness - these qualities are of great importance in the maintenance of building materials, including wallpapers, fittings, tiles, paneling, etc. There is also a trend of increasing demand for special modifications of the film, provided with additional operational properties.