Essential Components for Thermal Transfer Printing
Each printer component plays a vital role in producing high-quality labels in thermal transfer printing. Here's an overview of the essential mechanisms and their functions.
Ribbon Unwind
The Ribbon Unwind has one main purpose: to securely hold the thermal transfer ribbon (TTR) roll in place during printing. A Ribbon is wrapped around a core that fits perfectly onto the Ribbon Unwind. Typically, the Ribbon Unwind is positioned in front of the Label Unwind, and both are drawn under the Thermal Printhead by the movement of the Platen Roller.
Label Unwind
The Label Unwind keeps the roll of labels secure while the thermal printer is operating. During Thermal Printing, the labels and the thermal transfer ribbon are fed between the Platen Roller and the printhead. Once the image is imprinted on the label, the finished labels are pushed out of the printer by the Platen Roller.
Ribbon Take-Up Spindle
After the thermal transfer ribbon has been pulled through the Platen Roller and Printhead, it must be manually attached to the Ribbon Take-Up Spindle. The Ribbon Take-Up Spindle rotates opposite the Ribbon Unwind to collect the thermal transfer ribbon after it has passed through the thermal printing process. The ribbon take-up spindle allows for easy disposal of the used TTR.
Ribbon Sensor
The Ribbon Sensor is a crucial component of a thermal transfer printer. Its primary function is to detect whether the thermal transfer ribbon (TTR) is properly installed. The sensor also alerts the printer's internal computer when the TTR roll has reached its end, as indicated by the trailer film. While not all thermal transfer printers are equipped with a Ribbon Sensor (some utilize an End Core Sensor), its purpose is to detect when the TTR roll is finished. Identifying the end of a TTR roll before it reaches the thermal printhead is essential for protecting the printhead from damage.
End Core Sensor
The End Core Sensor is located inside the Ribbon Unwind mechanism. Its primary function is to detect a lack of motion from the Ribbon Unwind. This process is closely linked to the End Film of the thermal transfer ribbon (TTR) and its adhesion to the core. When the TTR reaches the end of its roll, the continuous rotation will detach the End Film from the core, causing the Ribbon Unwind to stop rotating. The End Core Sensor will detect this lack of motion and alert the thermal printer's internal computer to stop printing.
Thermal Printhead
The Thermal Printhead is the key component of a thermal transfer printer. The printer consists of a specific number of heating elements that determine the printer's resolution. When these heating elements are activated, they transfer heat through the thermal transfer ribbon (TTR) onto the label substrate. This process, combined with pressure, allows the melted ink to be transferred effectively onto the label, completing the printing process.
Platen Roller
The Platen Roller is a stationary component located directly beneath the Thermal Printhead, playing a multi-functional role in thermal printing. A small motor spins the Platen Roller, facilitating the movement of ribbon and labels through the thermal printer and under the printhead. Additionally, the Platen Roller assists in feeding the thermal transfer ribbon (TTR) and labels into the printer.