In recent years, shrink sleeve labels have been growing at a high rate and gaining momentum around the world. According to AWA forecast, the global heat shrink sleeve labels market will grow at a CAGR of 8% from 2020 to 2023, and the demand for shrink sleeve labels market reached 14.296 billion square meters in 2023.

The market demand for shrink sleeve labels has achieved double-digit growth, which is mainly because shrink sleeve labels can cover the entire bottles, cans, jars, or any containers, providing 360° labeling design, and also be added with diversified post-process decorative processes, such as foil stamping, matte coatings, and so on for sleek and attractive designs.

A prominent trend in the shrink sleeve label market is the increasing demand for environmentally sustainable and eco-friendly products. It is also noteworthy that more and more printing technologies and processes are being combined to improve the quality and efficiency of shrink sleeve label production.

The main application area for shrink labels is the beverage industry. In addition, the growth momentum in the food, nutraceutical, beer and personal care industries is also impressive. In some new growth areas such as the beer industry, the growth rate of shrink sleeve labeling has even exceeded 50%.

As more and more manufacturers turn to shrink sleeve labels as the packaging labels for their products, but some of them are lack of knowledge about shrink sleeve labels, such as how the shrink sleeve labels are printed. Here has a complete introduction about the printing technology of shrink sleeve labels, hoping help customers to make a wise decision.

Shrink Sleeve Label Printing Methods

Shrink sleeve labels generally adopts reverse-side printing technology, and the main printing processes include: gravure printing, flexographic printing, rotary offset printing and digital printing. The selection of shrink sleeve label printing methods needs to refer to the customers’ requirements for the final shrink sleeve label product, such as printing quality, product life cycle, inks, coating effect, time-to-market, as well as cost and environmental requirements.

Gravure Printing – Suitable for Large Quantity

Gravure printing is the most popular and commonly used method for the printing of shrink sleeve labels in large quantities. Gravure printing plates are highly accurate and the printing quality on shrink film is also the best of all printing. The solvent-based ink used in gravure printing has a thick ink layer and a strong sense of three-dimensionality, resulting in rich layers of graphics after printing.

And the printing capacity of gravure printing plate can reach several million sheets. For large quantities, it is undoubtedly the most cost-effective printing method for shrink sleeve label. Therefore, gravure printing is more suitable for high-volume production. But gravure printing plate is complicated, has long cycle and high cost. And it is easy to pollute.

Gravure printing of shrink sleeve labels mainly adopts the unit type gravure printing machine. Nowadays gravura printing machines are almost equipped with automatic tension control system and automatic color register control system, which can automatically adjust the tension in the unwinding area, printing area and rewinding area according to the measured error between the color register marks, so as to ensure that the tension in the printing process is not chaotic and the correctness of the register.

Flexographic Printing – Environmental Frinedly Methods

With the development of flexographic printing technology, more and more shrink sleeve label manufacturers are choosing flexographic printing equipment to process medium and long orders of shrink sleeve labels, especially with UV flexographic printing; and on a smaller scale with aqueous flexographic printing.

Flexo printing has bright colors, the thickness and high gloss is same with that of gravure printing methods, which is comparable to gravure printing. Moreover, flexo printing mostly uses water-based ink, which is more conducive to environmental protection. As we all know, flexographic technology is the most environmentally friendly printing technology in labelling industry. Therefore, for users who have high environmental requirements, flexographic printing is a more suitable printing method to produce shrink sleeve labels.

Compared with the laminated type and unit type flexographic printing press, the CI type flexographic printing press is more suitable for shrink sleeve label printing. Because in the printing process, each color group shares a common impression cylinder, the printed material and the impression cylinder are firmly affixed, the change of tension is small, so that the material’s tensile deformation is small, and the register accuracy is high. The size of the tension adjustment, to be determined by the film type and tensile strength.

For example, if shrink film’s tensile strength is weak, it is easy to stretch and deform, and the tension should be small accordingly; while for shrink film with strong tensile strength, the tension can be larger accordingly. Because shrink film in the printing process is more susceptible to changes in tension, resulting in impermissible overprint, so in flexo printing process, we must pay close attention to the control of tension, to maintain the tension of the unrest and balance.

Digital Printing – Low MOQ and Small-batch Requirements

With the changes in many markets and the rise of small and micro enterprises, there are many new demands for shrink sleeve labels, such as multiple designs for multi-sku or multi-verion, special label designs for new products or new markets testing, various personalized designs, shortened delivery time, and more. Under such new market demand, the shortcomings of traditional wide web gravure printing began to come to the fore.

The flexibility and rich solutions of digital printing can just make up for the shortcomings of traditional gravure printing. Digital printing of shrink sleeve label is becoming more and more popular and the market share is gradually increasing. When using digital printing technology, the following points must be paid attention to: Firstly, the adhesion strength of the material to the ink; Secondly, the curing method and working temperature of the equipment. For different printing methods, the material must be pre-treated and coated with the next layer to obtain relatively ideal printing results.

Combination Printing – New Trend for Shrink Sleeve Label Manufacturing

Combination printing is rapidly developing in recent years, and widely used in the field of high-grade packaging and labeling. It is a combination of offset printing, flexographic printing, gravure printing, screen printing and other different printing methods and post-press processes, such as varnishing, oiling, foil stamping, die-cutting, laminating, cutting leaflets and more to complete the processing of printed products in a single on-line production.

Coupled with the progress of digital printing, the combination of printing technology can be adopted in new forms of combination, which is especially suitable for the current printing market to meet the trend of increasing short orders, increasing demand for decorative effect, anti-counterfeiting function and information load of printing products, and diversification of printing materials in the design of printing and packaging.

The combination printing of shrink sleeve labels, with flexographic printing process as the main body, can be combined with silkscreen, offset, letterpress, digital printing, cold transfer, hot stamping, laminating, creasing, embossing, slitting and die-cutting, and so on. The shrink film labels processed by this unique process are more exquisite, making the visual effect of packaging more high-end.

Pre-press Treatment Before Shrink Sleeve Label Printing

For shrink sleeve labels, shrinkage distortion is unavoidable in the printing process, sometimes even more serious. And the shrinkage deformation in different directions and positions may be different. Therefore, it is very important to do a good job in the design of the graphic and barcode shrinkage deformation error before printing. And it is also the difference between the production of shrink sleeve labels and other pressure sensitive labels. The following is a brief introduction on how to deal with the pre-press process.

Pre-Press Treatment of Heat Shrink Film

Theoretically, it is believed that to obtain good printability on plastic films, the surface tension of the film should be higher than that of the ink. At the same time, the surface should have a certain degree of roughness to form adsorption. Plastic films, such as polyolefin PP, PE film, is a non-polar polymer material and has chemical stability. So, its surface tension is small, lower than the tension of the ink, so the ink adhesion ability is poor.

Although the surface tension of some shrink films is comparable to the ink tension, or even higher, its surface is smooth, no pores, and the ink cannot adhere to the surface of films. At the same time, a variety of films in the synthetic resin are also added to the opening agent, antistatic agent, aging agent, which will also affect the surface properties of the film and make its printability deteriorate. Therefore, there are some printing suitability problems in most of the current shrink films.

To improve the printability of shrink film surface, it is necessary to pre-treat the surface of shrink film with poor printability to improve the surface tension and surface adsorption. Commonly used treatment methods include electrostar treatment, plasma treatment, chemical treatment, coating treatment method and so on.

Graphic Size of Shrink Labels

The determination of graphic size on shrink sleeve label should be based on the thickness of the shrink film, the transverse and longitudinal shrinkage of the film, the permissible shrinkage in all directions after packaging, and the permissible deformation error after the shrinkage and deformation of the graphic so as to ensure that the graphic after the shrinkage and deformation can be accurately restored.

Graphics Designs of Shrink Labels

The graphic design of shrink labels needs to consider the shape of the container. Designers in the prepress department need to deform certain parts of the label correctly, and where possible, not place key images in areas with high shrinkage. In addition, it is also possible to work with the container manufacturer so that the container has the right density to provide the correct shrinkage, both in the smaller sized areas and in the larger sized areas.

Shrink Sleeve Label Printing Manufacturer – Hengping Industry

The shrink sleeve label provided by Hengping Industry is adopted the most suitable printing methods based on customer’s actual requirements and is made of high quality, high shrink ratio shrink film materials. And the production of our shrink sleeve label can be combined with latest post-press processing technology, which will make your packaing labels outstanding in the market.