Diagraph's Blog

The Art of Automatic Label Dispensing

By Steve Dods, Product Manager 

Automated Labeling Products (ALP) and Thermal Transfer Overprinter (TTO)

The Art of Automatic Label Dispensing:

·   The amount of release agent (silicone coating) applied to the paper portion of the liner substrate

·   The aggressiveness of the adhesive being used for the label, usually determined by the         application need

·   The angle of the peel blade

·   The tension that is developed on the opposing sides of the peel blade

·   The addition of an air knife or pressurized flow of air to force a separation between the label and the liner at the peel point

·   The depth of the die-cut (the cutting process of forming the label within the continuous adhesive top sheet)

·   The age of the materials and storage conditions

When these factors are not within the bounds of system acceptability, the possible results are:

·   The label does not separate from the liner at all, and follows the liner over the peel blade. No label is separated. Extreme case.

·   The label begins to peel, but the angle of separation changes (due to adhesive aggressiveness/lack of tension/not enough release agent) and the label does not feed out to the designated retaining surface for application

·   The label peels out to the retaining surface for automated application, but the trailing edge is still connected to the edge of the liner. Upon application, the label hinges or rotates about this edge, and is ultimately not applied to the product

Two views of labels hinging onto the liner after traversing the peel blade edge. The labels remain attached to the liner.

Problems with the Current Solutions:

·   Alternate designs will use an air knife and air pressure to separate the label from the liner. This creates a potential issue of blowing the label off of the tamp pad and into the air, since the amount of pressure is constant and the bond resistance varies from label to label. No label applied to product.

·   Alternate designs will allow the label to feed out to the tamp pad, and then use articulation to move away from the peel edge. This results in extra moving parts and more failure points. This method does not solve other aspects of peeling, such as label face stocks with increased friction and drag resistance.

The Solution:

To solve the issues of dispensing labels with the aforementioned attributes, the system was modified to perform a vibrating function by way of the preexisting brushless dc actuator motor. Since the heart of the All-Electric labeling system design is based on a proprietary circuit design and control algorithm, changes could be instituted to allow the surface of the tamp pad (the holding plate for the label prior to application) to vibrate during the feed of the label. The vibration effect is only active after the feed of the label, which breaks the adhesive fiber bonds that would normally be maintained between label and liner without this technology. By vibrating in the low Hertz range, the system can separate labels that would otherwise hinge and cause label jams or cause the label to avoid being applied with adhesive side facing the product. This patented method of ensuring the labels are freed from the liner is known as VibraFeed.

Innovation Benefits:

·   Automatically separates the label adhesive fiber bonds with the liner without increasing the process time

·   Uses inherent components of the system that are normally tasked with the application of the label to the product

·   Increases the range of label material quality that can be used for automatic application

At Diagraph, we are dedicated in solving your coding and labeling challenges. Diagraph has been assisting customers for over 120 years improving production line efficiencies with simple, reliable, cost-effective coding and labeling solutions. Contact us to learn more about the Automated Label Applicators product line. Visit us at www.diagraph.com or contact us at 800.722.1125.