What Are Black Bars and Why Does Your Label Need One?

In the world of labels, black bars play a crucial role in the seamless application of labels onto products. Printed on the bottom of the liner, these marks are pivotal in ensuring labels are applied accurately and efficiently. In this blog post, we’ll dive into what black bars are, why they’re important, and why your label might need one!

Understanding Black Bars

Black bars, in the context of label application, refer to printed ink on the label liner that serves a specific purpose – triggering the sensor on label application machines. These sensors are strategically placed within label applicators to detect the presence and position of labels, ensuring accurate and precise application onto products. The requirement for a black bar on a label is influenced by two main factors: the type of label applicator and the type of label being applied.

Labels That May Need Black Bars

Clear Film Labels
One of the key scenarios where black bars come into play is with clear film labels. The sensors on older labeling applicator machines might not pick up the beginning of a clear label due to its transparency. This is where black bars come to the rescue! The contrast provided by the black bar enables the sensors to accurately identify the starting point of the label, ensuring proper alignment and application.

Paper Labels with Unique Die Shapes
While primarily associated with clear film labels, paper labels might also require black bars in specific situations. This most often occurs when the label has a unique die shape and an older applicator is being used. As with clear film labels, the black bar can aid the sensor in detecting the label’s position, ensuring precise application.

Technical Specification Form (TSF)

The use of black bars is an important consideration during label design and production. This is where YL’s Technical Specification Form (TSF) comes into play. The TSF includes questions related to label application, and black bars are a key component of this inquiry.

The form also addresses other factors that can trigger machine sensors, such as eyemarks on the label face. An eye mark is a black box that is printed on the edge of the label, or on the liner, and is read by a machine to know where one labels starts, and the next ends. The function of an eye mark is similar to a black bar in that it is used to assist with label application.

Visualizing the Concept

To better understand the role of black bars and their significance in label application, take a look at the graphics pictured below that depict two different ways a black bar could be printed on the liner. This helps to showcase the actual implementation of black bars on labels and how they may interact with labeling machinery.

To learn more about Black Bars or if your label may need one, reach out today!