What affects the print quality of labels on Zebra printers?

Zebra printers have a reputation for reliable label printing in industrial, logistics, retail and healthcare. They are considered to be high-quality equipment that guarantees precise prints even with intensive use and in demanding industrial conditions. However, sometimes there are problems with a blurred print or an illegible barcode.  In this article, you will learn how the settings of printing parameters and the selection of the right material can affect the quality of label printing.

Zebra printer supplies

Zebra printers’ print quality is heavily influenced by the supplies you use, such as ribbons and the labels themselves.

• The most common problem related to the quality of the print is an improperly selected ribbon – not adapted to a specific type of label. Printing with an inappropriate thermal transfer ribbon “does not stick” well to the surface of the label, it may wear off and smudge over time. If you want high-quality printing and good readability of barcodes, don’t buy the cheapest ribbon. The apparent savings when buying a low-quality thermal transfer ribbon can cost you an increased number of returns and complaints later on, caused by illegible barcodes.  Read how to choose a thermal transfer ribbon for labels
• Using thermal labels to mark collective packaging and pallets is a convenient and inexpensive solution, as they do not use ribbon to print on them. However, under the influence of temperature and sunlight, the print on thermal labels fades and is illegible. Therefore, if the products are stored for a long time or pallets are placed in an external storage yard and the labels are to be legible, then instead of thermal labels, use thermal transfer labels for the markings.
• Another mistake is also using labels that are not suitable for thermal transfer printing or labels from an unproven supplier. Good quality thermal transfer labels are coated with a special couting, which guarantees good adhesion of the dye from the thermal transfer ribbon. Using labels for laser, inkjet or flexography printers, although this happens less and less often, can cause the print to smudge.

Settings affecting print quality on Zebra printers

The print quality also depends on the appropriate setting of the print parameters. 

• Print temperature setting (blackness/density). The selection of the appropriate value (0-30) of this parameter should depend on the combination of labels and the ribbon used (wax, wax-resin, resin). Too high a printing temperature leads to overheating of the ribbon, too much dye sticking to the label, creating an ugly, irregular print. It also reduces the life of the print head heating filaments. On the other hand, too low printing temperature may cause some elements to remain unprinted. It should also be remembered that when changing the material and/or type of ribbon, you will need to set a different temperature again.
• Another important factor is the printing speed. We also adjust the printing speed to the size of the labels and the amount of graphics. If the material moves too quickly under the head, some elements of graphics or codes may be inaccurately printed. Therefore, it is important to adjust the print speed to the desired print quality.
• Pressure balance (right – left) of the printhead. This applies to semi-industrial, industrial printers that print from the left side, where the material is not centrally guided. Uneven pressure of the printhead across the entire width of the material (labels on the backing) can lead to deterioration of the print quality on one side of the labels and wrinkling of the dye ribbon (diagonal unprinted lines).
• Printhead pressure. This applies to semi-industrial and industrial printers. The contact force of the printhead against the material should be set optimally. Too little head pressure can lead to poorer print quality on the entire label. Too high for the printhead heating filaments to wear out quickly.

Damaged Zebra printerhead

The quality of printed codes, texts, and graphics can be affected by wear and tear on the print head. Damaged (burned, worn) head filament does not heat up and does not print in this place. On the label, in the place where the black print should be, there are unprinted vertical lines. Printed graphics may look unsightly, and the barcode may not be readable by barcode readers. In this case, it is necessary to replace the printhead with a new one.

Dirty printhead

Another problem is the white spots on the black prints, which are usually caused by dirt on the printhead. To avoid these kinds of problems, clean the printer head regularly, removing any stick, dye, and small debris.

Low printhead resolution

Printers with low printhead resolution (203dpi) may not provide optimal print quality, especially with small fonts and graphics. For applications where accurate printing of barcodes and 2D codes on small labels is required, high-resolution 300dpi and 600dpi head printers are recommended. This is particularly important when printing 1D/2D codes graphically, e.g. usually from PDF files, where the scaling errors of such “graphic” codes decrease with increasing the print resolution.

Read how head resolution affects print quality

Poorly prepared graphics

Thermal transfer printers are designed mainly for printing industrial, single-color markings. There are also no shades of gray printed, there is only either a white dot (no print) or black (print). When designing a logo label, you should carefully prepare monochrome graphics in advance, preferably in lossless bmp, png format for a specific resolution. Although color or grayscale images inserted on the label will be automatically converted, they may not be printed in satisfactory quality. You should also make sure that the label designer program supports jpg, png formats.

See the ETILABEL program for designing and printing labels

Zebra’s high-end printers won’t guarantee you high-quality printed labels. Always make sure you have the right materials, clean your device regularly, and optimize your print settings.

If you need support in choosing a printer, software and consumables, contact us!