Have You Ever Experienced “Liner Tears” on Your High-Speed Auto-Label Applicator Lines?

If you answered yes, it may be time to ask your label supplier some questions about the liner they’re currently using on your roll labels. There are various factors that can lead to in-line labeling issues, and defective liners are one of them. While there are many types of liners on the market, three main types are most commonly used in the Narrow Web Label Converting Industry:

1. SCK (Super Calendered Kraft)
2. Glassine
3. PET or other poly materials with different mil thicknesses 

Each of these liners has its pros and cons and varies in price. SCK liners are the most economical and are widely used.
 
Common Scenario
You’re running a high-speed bottling line when suddenly, the liner tears, halting your production! You stop the line, reload the labels, and hope that fixes it. But if the issue persists, you’re facing the dreaded “liner tear.” Today, I want to focus on the classic “V”-type tearing (insert image here), a common problem with SCK liners, which are particularly prone to this issue.

During the manufacturing of an SCK liner, pulp and fillers like clay and other minerals are compressed between hard steel and soft cotton rollers to achieve a smooth, glossy paper finish. This finish allows the liner to be coated with a silicone release agent. However, during the silicone coating process, occasional “voids” may appear on the liner’s surface. These voids enable adhesive to bleed into the liner fibers, potentially causing the label stock to stick or tear during the in-line label application process. Unfortunately, label converters have limited means to detect these voids other than spot-checking via peel tests on finished rolls—but this is no guarantee.
 
Solution:
If you’re running a high-speed label applicator, consider testing a poly (PET) liner from your label supplier. Testing is recommended, as there are many variables involved. Why PET? PET offers more consistent performance at higher application speeds and reduces web breaks due to its higher tensile strength compared to paper liners. Additionally, PET liners allow you to fit more labels on a roll since they are typically thinner than paper liners.
​ 
If you have questions about choosing the best liner option for your label application, feel free to reach out.

---

---