Most professional and industrial label printers allow you to choose between two thermal printing methods for label printing: thermal transfer and thermal. Which approach should you choose for your business application? Here’s everything you need to know for perfect labeling results!
The difference between thermal transfer printing and thermal printing
First, let's talk about the similarities: Both label printing methods require a thermal printhead that applies heat to the surface being marked. The printhead consists of tiny heating elements (dots) that heat in selected areas to produce the desired printed image. Therefore, the fairly general term thermal printer can be used for direct thermal label printers as well as thermal transfer printers. Their print resolution is determined by the size, number and arrangement of heating elements and is measured in dots per inch (dpi). Typically 203, 300 or 600 dpi. The higher the number, the higher the print resolution and quality.
The actual difference between the two methods is the surface that the printhead heats: Thermal transfer printing uses a wax- or resin-based ribbon that transfers ink to the label when heated. Direct thermal printing, on the other hand, uses thermal labels that turn black where they are directly heated.
How does a thermal transfer printer work?
In thermal transfer printing, the printhead's heating element applies point-like heat to the passing ribbon, causing it to melt onto the label and form the printed image. The label absorbs the ink, making it part of the media. Ribbon and label materials (materials and adhesives) must be carefully matched to each other and to the specific application for optimal quality and durability.
How does a thermal label printer work?
In direct thermal printing, the printhead's heating element applies heat directly to a passing label that has a thermal coating. Chemical reaction causes label color to change from white to black
Thermal Transfer Printing and Direct Thermal Printing for Label Printing – Comparison
In general, thermal label printers are ideal for producing barcode labels because they can create high-quality images with excellent edge definition, which is necessary for barcode scanners to successfully capture data. For more on this topic, check out our 6 tips for improving barcode quality and our quick guide on how to check barcodes without a scanner.
We would also like to add that you can use thermal printing methods to print linear and 2D barcodes, such as Data Matrix codes or QR codes. Of course, the same goes for text and graphics.
Let’s compare the performance of each method in different categories:
Thermal transfer |
Direct thermal |
|
| Print quality | Maximum readability and scannability | Good readability and scannability |
| Print durability | Long-life image stability | Extremely sensitive to heat, light and other environmental conditions (label will darken when overexposed to such) |
| Color printing | Possible with colored ribbon | Only black and white |
| Print head life | Ribbon acts as buffer between print head and label material; ribbon back-coatings reduce static and friction | Direct contact with abrasive labels (and possible dust and debris) promotes wear-out and increased replacement costs |
| Printer configuration and maintenance |
More downtime due to ribbon changes and adjustments Regular parts cleaning recommended (see our thermal printer maintenance tips) |
Simple to operate, because no ribbon must be monitored or replenished Regular parts cleaning recommended (see our thermal printer maintenance tips) |
| Media selection and cost |
Can print on great variety of media stock Ribbon and media substrate must be compatible to avoid problems Lower cost for thermal transfer labels (additional ribbon required) |
Can print on heat-sensitive paper/labels Higher cost for direct thermal labels |
| Environmental aspects |
Enables batch or single label printing with virtually no waste Linerless materials available Poor ribbon recycling |
Enables batch or single label printing with virtually no waste Recyclable materials available |
| Typical applications | Product and packaging labels, GHS labels, asset tags | Shipping labels, receipts, tickets |
