Shrink film label printing review

At present, the printing method of shrink film labels is still mainly gravure printing, and the share of flexographic printing methods is relatively small. Shrink film labels also have certain requirements for printing equipment, mainly in tension control and heat control.

Since the film material is easily deformed by stretching, it is necessary to precisely control the printing tension when printing such materials. Some older models of presses or printing machines designed specifically for adhesive film labels with substrates are simply not suitable for the printing of shrink film labels.

In the printing of shrink film labels, the heat control of the printing press is also very important. It is required that the printing machine must be able to disperse and eliminate heat and prevent the shrink film from shrinking during the printing process. Some newer presses are equipped with chill rolls to remove heat and lower the temperature of the film.

For shrink sleeve printing, a sealing device is also needed to change the film into a tube and seal the overlapping parts together (to form a seam). Then the film is pressed flat and finally rolled up. . Sealing quality control and testing are very important so as not to affect the subsequent process of labeling. Sealing parts are generally not printed graphics, and to ensure clean, no dirt, otherwise it will affect the fastness to adhesion.

At present, the price of sealing devices is generally between 40,000 and 200,000 US dollars or even higher. Some high-price sealing devices are also equipped with detection devices. If you purchase the testing device separately, the price is between 30,000 and 50,000 U.S. dollars.

Labeling equipment and adhesives

Shrink sleeves generally require special labeling equipment to place the printed sleeve onto the container. First, the labeling device opens the sealed tubular sleeve label, which may sometimes require punching. Next, the sleeve label is cut to a suitable size and placed on the container; then, heat treatment is performed using steam, infrared rays, or hot air passages. , so that the label is tightly attached to the surface of the container.

The shrink-wraparound label can be labeled using conventional labeling equipment, requiring the use of adhesives and higher temperatures during the labeling process. During the shrinkage process, hot melt adhesives are preferred because the adhesive at the overlapping areas of the film will exert stress. In some cases, solvent-based adhesives may also be used. Although UV adhesives have once received much attention and are expected to be widely used in the labeling of low-shrinkage film labels, no breakthrough has been made so far.

At present, shrink-wrap labels are usually made from PP film. Because PP film shrinkage is not high, generally within 20%, therefore, the use of hot melt adhesive is more appropriate when labeling. If solvent-based adhesives are used, the PP film may wrinkle. Since the shrinkage temperature of the PP film is high, the heat treatment is mainly performed by a hot air method, which can achieve a higher temperature than the steam heating method.

Nowadays, high shrinkage film labels are used more and more, and in the process of shrink labeling, the heat seal area will produce more stress. In order to withstand this shrinkage stress, the demand for solvent-based adhesives will increase in the future.

Shrink Film Printing Success Story

Since its establishment in 1988, SleeveCo has been focusing on shrink sleeve labeling and drawing sleeve printing. According to Martin Wilson, deputy manager of the company's sales and marketing department, the company's ability to cooperate with some of the world's leading consumer goods manufacturers on many challenging projects is also inseparable.

In addition to the prepress and printing divisions, SleeveCo has also begun to extend downstream of the process to manufacture various sets of labeling and labeling equipment. When processing complex shrink labels, everything from design to labeling must be accurate, and SleeveCo can provide the expertise needed for the entire process.

1. Produce high-quality shrink sleeves

SleeveCo company is facing a number of very strict market requirements for product labels, including automotive aftermarket, cosmetics market, consumer goods market, greening and garden products market. SleeveCo uses solvent-based inks when printing shrink-sleeve labels. Substrates suitable for gravure printing include PVC, high-shrinkage PVC, PETG, OPS, and OPP films. When printing on flexographic printing presses, PP is mainly used. film.

Since SleeveCo has both gravure printers and flexo printers, it has a high degree of flexibility in production and can choose the appropriate printing method according to the product. Flexographic printing presses are suitable for printing tickets, coupons, lotteries, and the like that require 100% of the material to be completely recovered, and to prevent the leakage of the chemical substances in the container and the contamination of the labels. In addition, it is also suitable for printing drums with a printing capacity of 8 ounces to 55 gallons, and can select ink color and screen number according to the image color density requirement.

With gravure printing, SleeveCo can also provide photo-quality image quality, and can use special inks (including metallic inks, pearlescent inks, mixed inks, and matte varnishes) for printing. Some have translucent labels. It's like there is no label.

2, practice experience

Since SleeveCo is a company specializing in sleeve label printing, the type of job processing is also wide. From ordinary sleeve labels to more complicated sleeve labels with certain difficulties, even some innovative new products, if necessary. The company will also spend several months on R&D to make the product's indicators more perfect, such as size, deformation rate and image quality, so many packaging users have come here.

Mr. Wilson particularly emphasized the company’s example of the development of a shrink label for a petrol container of the Pennzoil-Quaker State for several months. He said: “Gas cylinders are similar in shape to racing cars, and other companies in the industry think that this product should not be used as an overall shrink label. In order to make the label shrink, it just can be wrapped outside the shape of a car bottle (the wheel and the hood part of the label must be The company's pre-press department's designers performed correct deformation of certain parts of the label. In addition, our company cooperated with bottle manufacturers to make the density of the bottles suitable. , and developed a special system for sticking such labels."

Another challenging project is the successful development of shrink sleeves for Blue Corral's Black Magic series. Blue Corral wants to use an overall shrink sleeve for its spray gun bottle. The main challenge is the deformation of the bottleneck. SleeveCo has developed a solution that provides the correct shrinkage, both in the smaller caps and in the bottom of the larger caps.

The successful application of shrink labels and special inks has led to a significant increase in the company's business. Mr. Wilson said: “Our customer, White Rock Distilleries, intends to change the product packaging from the original frosted etched glass to the integral shrink sleeve label, and after matt glazing can also achieve the original effect. This saves the company a There is a large cost and the bottle inventory is reduced."

3. Opportunities and Challenges

Although SleeveCo Company is facing the packaging printing market which is currently growing, it still faces some severe tests.

Mr. Wilson said: "The biggest problem comes from the end user's requirements for speed and timeliness. The market and major retailers (such as Wal-Mart) require that the delivery cycle of the supplier (that is, our customers) be shortened every time. The amount of supply needed is also gradually decreasing. The key to our company's success is to address these issues and to properly formulate the initial project plan so that we can help our customers to quickly enter the market."

In spite of various challenges, Mr. Wilson believes that the development prospect of shrink sleeves is bright. He said: "With the further development of shrink sleeve technology and the deepening of people's understanding of shrink sleeves, plastic container blow molding companies are now able to produce a variety of odd-shaped bottles that are more attractive and humane, despite the shrink sleeves. The cost of the target is slightly higher than the pressure sensitive label and the paper label, but it can bring higher added value to the product."