Heat shrink film label introduction

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 outline of the container and cling to the surface of the container. 

Heat shrinkable film label mainly includes shrink sleeve label and shrink wrap label. Shrink tube label is a tube label made of heat shrink film as the base material, which is convenient to use and is very suitable for special-shaped containers. 

Shrink-sleeve labels generally require special labeling equipment to attach the printed sleeve label to the container. First of all, the labeling equipment will open the cylinder sleeve label after sealing, and sometimes it may need to punch holes; Next, cut the sleeve label to a suitable size and put it on the container; Heat treatment is then carried out using steam, infrared or hot air channels so that the sleeve label is tightly attached to the surface of the container. Because of the high transparency of the film itself, the label has bright color and good luster. However, because it must be shrunk when used, there is the disadvantage of pattern deformation, especially for products printed with bar codes. Must go through strict design and printing quality control, otherwise the pattern deformation will cause the bar code quality unqualified. Shrink wrap labels can be labeled with traditional labeling equipment, which requires the use of adhesives and higher temperatures. During the shrinkage process, because the adhesive at the overlapping part of the film will produce stress, it is better to use hot melt adhesive. 

At present, heat shrink film shrink wrap labels are usually made of PP film. Because the shrinkage rate of PP film is not high, generally within 20%, it is more appropriate to use hot melt adhesive when labeling. If solvent-based adhesives are used, folding of PP films may be caused. Due to the high shrinkage temperature of PP film, heat treatment is mainly carried out by hot air, which can reach a higher temperature than steam heating. 

Shrink film label is a part of the label market, is currently in rapid growth, the market share continues to expand, is expected to annual growth rate of about 15%, much more than the ordinary label market annual growth rate of about 5%, the development potential is huge, become a bright spot in the label printing industry. It is predicted that the domestic heat shrink film market will grow at a rate of more than 20% in the next five years. 

The food industry is the largest market for heat shrink packaging. Heat shrinkable film is widely used in all kinds of fast food, lactic acid food, beverage, small food, beer cans, all kinds of alcohol, agricultural and sideline products, dry food, local specialties and other packaging. At present, the customer base of the shrink film label market is mainly some large FMCG companies, such as Procter & Gamble, Unilever, Shanghai Jahwa, etc., whose products are large in batch and require long plate live printing. The initial investment of gravure printing is high, but the high printing resistance and low relative cost of gravure printing make it the first choice for shrink film printing. And the graphic part of the printing plate is concave, so you can get a solid ink layer, bright colors and rich layers. 

In recent years, with the promotion of flexographic printing, some shrink films are also printed by flexographic printing, especially PE materials that cannot withstand too much tension, and most of them use CI flexographic printing presses. In the non-food field, the application of heat shrink film labels is also increasing, such as labels and bottle caps, seals, cosmetics, pharmaceuticals, daily chemical products, sporting goods, kitchen supplies, daily necessities, etc. At the same time, it has been widely used in the fields of ceramic products, tea sets, mechanical parts, building materials and transportation materials. Because the 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 what kind of printing method is used for printing, before the design of the surface pattern, the horizontal and longitudinal shrinkage rate of the material should be taken into account, as well as the deformation error allowed in each direction of the decorative text after the contraction, in order to ensure the accurate restoration of the pattern, text and bar code on the container.