Heat shrinkable film label is a kind of film label printed on plastic film or plastic tube with special ink, in the process of labeling, when heated (about 70 °C), the shrink label will quickly shrink along the outer contour of the container, close to the surface of the container, heat shrinkable film label mainly includes shrink sleeve label and shrink wrap label.
Because heat shrinkable film is a thermoplastic film that is stretched and oriented during the production process and contracted by heat during use. Therefore, no matter which printing method is used for printing, the horizontal and vertical shrinkage rate of the material and the allowable deformation error of the decorative graphic in all directions after shrinkage must be taken into account before the design of the surface pattern, so as to ensure the accurate restoration of the pattern, text and bar code shrunk to the container.
Usually the barcode should be placed in the same direction as the direction when printing, otherwise the lines of the barcode will be distorted, which will affect the scanning result and cause misreading. In addition, the color selection of label products should be based on spot colors as much as possible, and the production of white version is a must, which can be made into a full version or hollow according to the actual situation. The color of the barcode should follow the general requirements, that is, the color matching of the bar and the empty should conform to the color matching principle of the barcode. Selection of printed materials. The printing of heat shrinkable labels has been briefly analyzed, and the material plays a decisive role in affecting its quality in addition to the control of the printing process. Therefore, choosing the right material is key. The thickness of the film material is determined according to the application field of the heat shrink label, the cost, the characteristics of the film, the shrinkage performance, the printing process and the labeling process requirements. Generally, the film thickness of shrink film labels should be 30 microns to 70 microns, and 50 microns, 45 microns, and 40 microns are more commonly used, depending on the labeling performance on the labeling equipment. For the label material selected, it is generally required that the shrinkage of the film material is within the application range, and the transverse (TD) shrinkage is higher than the longitudinal (MD) shrinkage. The transverse shrinkage rate of commonly used materials is 50%~52% and 60%~62%, and can reach 90% in special cases. The longitudinal shrinkage rate is required to be 6%~8%. In addition, since shrink film is very sensitive to heat, it is important to avoid high temperatures during storage, printing, and transportation.