Introduce the storage conditions and usage of PVC heat shrinkable film.

       Heat shrinkable film is a kind of thermoplastic film which is stretched and oriented in the production process, but shrinks when heated in the use process. The thermal shrinkage of film was applied as early as 1936. At the beginning, rubber film was mainly used to shrink and package perishable food. Nowadays, the heat shrinkage technology has developed to the point that almost all kinds of commodities can be packaged with plastic shrink film. In addition, shrink packaging is also used to make shrink labels and shrink bottle caps, so that containers that are not easy to print or have complex shapes can be labeled. Recently, new application fields have been developed. Production technology and characteristics The production of packaging film usually adopts extrusion blow molding or extrusion casting method to produce thick film, and then it is stretched longitudinally and transversely at a high elastic temperature above the softening temperature and below the melting temperature, or stretched in one direction only, but not in the other direction. The former is called biaxial stretching shrinkage film, while the latter is called unid irectional shrinkage film. When in use, when the temperature is higher than or close to the stretching temperature, the packaged goods are bound up by the contraction force.

Analysis on matters needing attention in using PVC heat shrinkable film;

• First, the shape of the container has different requirements for data shrinkage. For example, approximately cylindrical containers with low shrinkage requirements can consider using OPP or PVC data, while containers with more curves or streamlined planning can consider PVC heat shrinkable film with high shrinkage and strength.

• Secondly, PVC heat shrinkable film can be closely attached to various containers with different shapes, which can not only print exquisite pictures, but also achieve the application of various novel packaging containers with different shapes.

• Third, no poison, no smell, grease resistance, and in line with food hygiene standards. It allows planners to choose colors that are obvious to all, realize 360 label planning, and give full play to creativity and imagination, thus making label pictures more vivid, highlighting the image on the shelf, and causing unexpected container effect. For example, the new curved glass bottle of Blue Ribbon Beer in China chooses OPS base material with high shrinkage rate, and labels it with solvent-based adhesive.

• IV, PVC heat shrinkable film is used for sales and transportation of various products, and its main function is to stabilize, cover and protect products. Shrinkage film must have high puncture resistance, good shrinkage and specific shrinkage stress.

• Five,  in the process of shrinkage, the film can't produce holes. Because shrink film is often suitable for outdoor use, it is necessary to add UV agent. The small-sized heat-shrinkable packaging equipment carefully manufactured according to heat shrinkable film standard has the characteristics of simple operation, wide application range, good sealing performance, high transparency, low cost and high grade, and is suitable for the packaging of small and medium batch products.

• Six,  heat shrinkable film machine is used online with the labeling machine to form the labeling shrinkage machine line, which is generally applicable to the totally-enclosed heat-shrinkable packaging of products such as goods, food, drinks, stationery, ceramics, daily chemicals, auto parts, knitting, electronic audio-visual products, etc. It is the labeling shrinkage machine of the following packaging line.

       PVC shrink film should be stored in a sanitary warehouse with the temperature below 30℃,preferably below 25℃ and the humidity between 45% and 75%; Products need to avoid direct sunlight; PVC shrink film products are not less than 1m away from the heat source; It is forbidden to trample and handle products with sharp objects at the same time; The best time to use the heat shrinkable bag is within six months from the date of production. When the PVC heat shrinkable film is exposed to temperature, it automatically shrinks and tightly wraps the commodity, thus achieving the function of protecting the commodity, and also playing the roles of moisture-proof, rust-proof, pollution-proof, breakage-proof and theft-proof. Good stability in storage and transportation, simple packaging technology and equipment, and easy to implement automatic heat-shrinkable packaging. At present, the popular packaging in the market is mainly plastic and paper, and the blow molding industry, which is mainly plastic film blowing machine, accounts for a large proportion in the market. However, with the increasingly strict requirements for the paper industry, the new green and energy-saving index has raised the threshold of the paper industry, resulting in the expansion of the market cost and price of paper packaging. This makes the market share of plastic packaging in heat shrinkable film increase correspondingly, and stimulates the development of film blowing machine manufacturing machinery industry.

          In addition, PVC heat shrinkable film has high flexibility, difficult breakage, strong explosion resistance, strong impact resistance, strong tear resistance and strong tensile force, and can replace box packaging. PVC shrink film, with additional ingredients to enhance its heat resistance, toughness, ductility, etc. The upper layer of this surface film is paint, the main component in the middle is polyvinyl chloride, and the lower layer is back coating adhesive. It is a kind of synthetic material that is deeply loved, popular and widely used in the world today. Among the materials that can produce three-dimensional surface film, PVC is a more suitable material.