Graphic package designers are more inclined towards shrink sleeves to produce eye-catching, contour shaping, top-to-toe coverage for their consumer products. On one hand, these beautiful design on the packaging is pivotal to brand awareness and shelf-marketing, while on the other hand producing them is as much a science as it is an art. The world of shrink sleeve labeling is an intricate one. To achieve the optimum results, you’ll need to make sure you’re using the correct combination of the following three key components: (1) type of bottle, (2) grade of shrink film, and (3) heat shrink tunnel, for the best results. Following are a few key shrink sleeving tips to ensure your package design comes out as you envisioned it…
1. Containers’ shape and material considerations
The shape and material of your container is very important. If you want a full-body sleeve, choosing a container with a radius on the bottom for the film to “lock down to” is ideal. A container with a straight-walled bottom prevents the shrink film from conforming to a radius so the film will be inclined to pull up from the bottom of the container.
2. Container and sleeve tolerances
There are various tolerances that must be taken into consideration, like the tolerance of the container. For example, glass can vary in size more than most plastics. The tolerance of the sleeve when seamed during converting as well as the print to fold tolerance on the graphics, which impacts orientation of the sleeve to non-round bottles.
Create a design that will help to hide any inconsistencies or intolerances. For instance, don’t pick a black bottle and white film, any pull-up on the bottom will be obvious. Avoid design elements that may be visually detectable if there is a shift due to tolerances in film, container, printing, or application. The use of curving design is preferable to strict vertical and horizontal lines.
You should strategically consider all the above tolerances and plan for the worst case. Your selected sleeve applicator provider and shrink tunnel supplier could assist you and work with you on this subject.
3. Choosing the right film
A little understanding of the film that is used to create shrink sleeves would help in producing a great final product.
The four types of shrink sleeving film used on packaging include PVC, PET/PETG, OPS, and PLA. Each has unique shrink characteristics as well as advantages and disadvantages. Some films are well suited for packaging that will have tamper evident bands, such as PVC. Others, such as OPS, and PETG-LV work well with full sleeve applications that have little or no radius at the bottom.
Knowing the characteristics of the various films will allow you to make the right film choice for your product and budget, with no worries or surprises. Selecting the correct film will be the most cost-effective and avoids cost overruns. It’s best to work with the shrink sleeve application machine manufacturer that can guide you and one that offers a testing process, so you avoid any oversights and select the correct film from the start.
A critical part of the shrink sleeve labeling process is the shrinking of the film onto the container. This is done via a shrink tunnel that mounts over the production line conveyor. Your container could encounter a wide range of temperatures depending on the type of shrink tunnel used (Hot air or Steam tunnel). In steam tunnels, for example, temperatures generally run between 79°C and 99°C. Electric tunnels can reach temperatures of 93°C up to 300°C near the heat elements.
Typically bottle deformation occurs with empty plastic containers. Filled containers, on the other hand, act as a heat sink, that transfers the heat to the substance inside the container, and so can therefore withstand higher temperatures without deforming.
If your container is plastic or it will be labeled while empty, testing it in the actual shrink tunnel to be used during production will let you know if the bottle will deform during the shrinking process.
5. Prototyping Your Package Design
This brings us to the importance of testing your product. It is best to discuss your planned design with film and heat tunnel manufacturers before moving too far along with a shrink sleeve labeling project. During the testing phase, a prototype of the proposed film on the actual container is run at production speeds in a hot air or steam tunnel.
If production labels are not available, you can test with grid printed film first in the recommended shrink tunnel. The grid will indicate how the film lays down around any contours and whether it is being pulled in a particular direction. You can then analyze the shrunk sample with grid film and take those factors into account when laying out the artwork for the printed shrink label in order to avoid any distortion issues on the final product.
Shrink sleeves allow the decoration of containers in ways that were impossible in the past. Knowing what to expect from the shrink sleeve labeling process will go a long way to producing eye-catching graphics that knocks it out of the park from the get-go.
We’re a global leader in shrink sleeving technology with ~38 years in the sleeve packaging industry.PDC Europe has years of expertise in helping customers choose the proper shrink film and shrink tunnels for a variety of product and packaging types. Our Shrink Lab is available to FREE test your product to ensure it will be attractive to customers and look terrific!
Contact us today at +33 (0)3 22 78 93 sales@pdceurope.com.
