A guide to print quality
If your thermal printer has poor print quality can cause huge problems such as unreadable text/barcodes, depending what customers you work with unreadable barcodes can even lead to financial penalties for the supplier or even rejected goods. This makes keeping on top of print quality significantly important to some businesses, sometimes getting it right is difficult and that’s where we come in.
To get the perfect print quality while protecting your printhead life it is important to balance the temperature and pressure settings.
These are the main factors that contribute to print quality on a thermal printer:
The Media (Labels, ribbons and paper)
Temperature (Darkness, Contrast, Intensity)
Pressure
Print speed
Media
The label and ribbon stock you select is the most important to obtaining good print quality, if you don’t get the label and ribbon combination right or you purchase poorly manufactured direct thermal labels it can lead to host of printing issues.
Ribbons are made out of either a wax, wax/resin or resin blend, if the ribbon compound doesn’t match your paper type it can have unintended consequences such as poor/little transfer or transfer without achieving the desired properties. For example using a wax ribbon on synthetic labels may appear to be good quality but rub off easily.
Choosing the right technology is also important direct thermal labels have a short shelf life as they are less resistant to light, heat smudging and scratching; whereas thermal transfer is perfect for longer term applications that require resistance to tougher environments and chemicals.
Temperature
The temperature setting is also important to the process and is referred to by different names depending on the printer manufacturer some examples include darkness, print Intensity and Contrast.
Too low and you get faded print quality, too high and you can end up with a host of other problems such as “bleeding” which is where the printed image appears blurry; it can also cause ribbon snapping and extra wear on your printhead which can be a very costly mistake.
Beware of naming traps such as “Darkness” increasing the darkness will only make the print darker until you achieve the full transfer of ribbon to label or the quality of the direct thermal label. For example depending on your media setting the Darkness to 15 will give the same print quality as 30 but will have a huge impact on how quickly the elements on your printhead wear out.
You should always try to get away with the lowest temperature setting that gives you good print quality to prevent unnecessary printer wear and maintenance costs.
Pressure
Printhead pressure is also extremely important to the process, a mix of pressure and heat is required to achieve optimal print quality.
Most desktop and mobile printers have set pressure which means it is not user adjustable so as long you use media that abides by the thickness specifications of the printer it should be ok.
Industrial printers have various user pressure adjustments, the general rule is you want to get away with using the lowest pressure possible to achieve the perfect print quality.
Uneven pressure settings can lead to fading or missing print on one half of the label, it’s important to balance the pressure for the width of labels you are using; most of this information can be found in the users manual for your printer. Too much pressure leads to unnecessary printhead wear which is often an expensive mistake.
Print Speed
You might be thinking how does the print speed make a difference to the quality? well the truth of the matter is the faster media moves through the printer the less time the printhead elements are in contact with the media.
This means less heat is transferred as a result and faded print may appear, if you need to use a quicker print speed for your application you may need to increase the temperature or pressure to offset the transfer time lost.