Since the heat shrinkable film is a thermoplastic film that is stretched and oriented during the production process and shrinks during use. Therefore, no matter which printing method is used for printing, before the design of the surface pattern, the horizontal and vertical shrinkage rates of the material, as well as the allowable deformation error in all directions of the decorative graphics and text after shrinking, must be considered, in order to ensure the pattern, Accurate restoration of text and barcodes.
Three points to note
1. Usually, the placement direction of the barcode should be consistent with the direction of printing, otherwise the lines of the barcode will be distorted, which will affect the scanning result and cause misreading.
2. 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 necessary, which can be made into full version or hollow according to the actual situation.
3. The color of the barcode should follow the general requirements, that is, the color matching of the bar and the blank should conform to the principle of color matching of the barcode.
Selection of printing materials
The printing of heat shrinkable labels has been briefly analyzed above. In addition to the control of the printing process, the material plays a decisive role in affecting its quality. Therefore, choosing the right material is key.
The thickness of the film material is determined according to the application field, cost, film characteristics, shrinkage performance, printing process and labeling process requirements of the heat shrinkable label. It is generally required that the film thickness of the shrink film label should be 30 microns to 70 microns.
For the selected label material, the shrinkage rate of the film material is generally required to be within the application range, and the transverse (TD) shrinkage rate is higher than the machine direction (MD) shrinkage rate. The transverse shrinkage rates of commonly used materials are 50% to 52% and 60% to 62%, and can reach 90% in special cases. The longitudinal shrinkage rate is required to be 6% to 8%.
Also, since shrink film is very heat sensitive, it is important to avoid high temperatures during storage, printing and shipping.
Post time: Mar-21-2022