Polyethylene is one of the most popular materials that are used as packaging. It is used in industry, manufacturing, in the trading industry, and, of course, ordinary housewives cannot do without it. Moreover, in each case, a suitable shape of the material is used according to its characteristics. This can be a bag, and a film sheet, and a primary sleeve. For example, from the point of view of operational value, a thermoshrinkable polyethylene sleeve is especially distinguished, which can be used both as a basis for storing products and as a protective agent.
Purpose and scope of shrink film
The main function of this material is to ensure the integrity of a product. The material prevents negative environmental factors, allowing the target product to retain its original properties. We can say that a huge range of packaging materials solves such problems, including an extensive assortment of ordinary polyethylene. However, the heat-shrink sleeve is distinguished by the ability to fit snugly to the storage object, which allows to save packaging space as much as possible during transportation. Where is this solution used more often? First of all, these are enterprises engaged in the manufacture and sale of food products. Also, tight and tight packaging is required for goods from the segment of household chemicals, printing products, office supplies and some types of building materials.
Varieties
All film shrink materials can be divided into three classes according to the type of raw materials used. So, these are products from polyvinyl chloride (PVC), polyethylene (LDPE) and polyolefin (POF) fabrics. It must be said right away that the PVC heat shrink sleeve is the most common for the reason that it maintains a sufficient level of tightness for storing most food products, but at the same time it does not interfere with gas exchange processes. Actually, in this ability lies the main difference between polyvinyl chloride and polyolefin. POF materials also meet the needs of manufacturers of products that are sensitive to air, but do not allow the penetration of any gases.
Significantly different already in other qualities and classic polyethylene material. It is often used to store groups of goods - for example, packages with several bottles or a pack of paper sheets. This shrink film is characterized by mechanical resistance, tensile strength and durability.
Specifications
Dimensional parameters are one of the main selection criteria for this product, if they are suitable for the rest of the quality. So, a film made of polyolefinol is produced in rolls with a width of 25 to 90 cm, and the pitch, as a rule, is 5 cm. As for the thickness, in this case it varies in the range of 12-25 microns. The length of the rolls can reach 1250 m. But ordinary household winding is at least 650 m. A PVC shrink sleeve for packaging has a less wide range of sizes. For example, such a cloth rarely exceeds 60 cm in width and 750 m in length. But the PVC film is different in thickness, reaching already 30 microns. Polyethylene materials are in approximately the same dimensional limits. By weight, the average value is usually in the range of 5-10 kg, when it comes to industrial rolls.
Operational properties
Although there are certain differences in the properties of different shrink materials, the basic qualities are the same. These include optimal indicators of mechanical resistance, sanitary and hygienic safety, the absence of tension, and inertness to chemicals. It is worth noting the light transmittance that a transparent shrink sleeve has, designed for packaging food products. But the main quality that distinguishes heat-shrink materials from the general segment is the ability to optimally take the form of the product being served. Shrinkage on average is 40-50% provided that the heat treatment parameters are correctly selected.
Shrink Technique
To perform the aforementioned heat treatment function, under which the web is reduced, special devices are used. This can be automatic or semi-automatic equipment designed to work with products of a certain size. Also, the units are divided into models of the tunnel and chamber type. This separation determines the ability of the equipment to work in different modes from the point of view of in-line service - piece or serial. In the process of performing this function, hot air streams act on the heat shrink sleeve. As a result, the working web is contracted, and it completely takes the form of an object for packaging. Moreover, each machine has additional options that save operators from routine labor. These, for example, include the function of cutting a roll.
How much does a shrink sleeve cost?
Specific prices for shrink material are determined by size, technical parameters and the presence of special properties of the film. However, manufacturers do not always produce products in batches of a certain format. For example, it is practiced to sell paintings according to the mass required by the customer. Standard shrink film is available on the market for an average of 150-200 rubles / kg. Thick large-format rolls cost an average of 3-4 thousand per 25-30 kg. But such volumes relate to batches designed for industrial needs.
Conclusion
Shrink technology has significantly increased the efficiency of packaging materials. It allows you to minimize the space occupied by large consignments, and at the same time maintain the necessary level of protective qualities. At the same time, flexibility is also provided in terms of providing format diversity. The modern thermoshrinkable sleeve is available with different indicators in width, length and thickness. If we take into account the possibility of endowing film canvases with a wide range of operational properties, then we can talk about the universality of this material. However, there are some restrictions on the use of shrink film. For example, such a material cannot be used in the maintenance of sharp and pricking products that do not have a protective shell. There is also a certain framework in terms of the possibilities of using the same polyvinyl chloride at different temperatures. But manufacturers also seek to eliminate these limitations by giving the film additional functions.