Technology seems to let us down at the most important times and thermal transfer printers are no exception. A regular routine to clean the print head will solve many problems. You can use printer wipes to clean printheads, platen rollers and label sensors every time you change the roll of ribbons or labels. Dirty printheads are the cause of most common printed image problems.
1. “Bitty” barcodes, voids and missing text
Dust and debris is drawn to the printhead and can come between the pixels on the head and the ribbon preventing the wax/resin on the ribbon from melting onto the labels in the correct places. Clean the printhead with a proper printhead wipe infused with Isopropanol.
Take a single cleaning wipe, wrap it around your finger and gently rub the printhead until clean. DO NOT use any abrasive cleaners or wrap the wipe around a sharp object to scrape off any residue. This will inevitably lead to irreparable damage to the head and a replacement print head will be required
2. Printed image problems such as blurred or indistinct images
(Clean! Refer to no.1) Check the print energy/ head temperature/ heat settings. Too much heat can lead to poor print quality with “bleeding” barcodes and the ink running. Also too much heat can weaken the structure of the ribbon and cause it to snap. Ideally turn the print head as low as possible and increase incrementally until you get the optimum print quality.
Also see print speed – whilst your thermal transfer printer may well be capable of running at 350mm/second do you really need it to run at this rate. Often a slight reduction in print speed has no impact on line production and will allow you to achieve the best results.
3. Snapping ribbons & “wrinkled” print
Check the printhead pressure setting to see if it needs adjustment. If this is set to high, it can cause printhead breakages and ribbon wrinkling that will cause a part of an image to go missing or go come out at an angle. If the missing section is like an angled line going across the image it’s likely the ribbon is wrinkling.
4. Missing print
If some of the print is missing please check 1,2 & 3 above and also ensure the thermal transfer ribbon is slightly wider than the label. This will allow printing right up to the label edge. As an added benefit the special back coat on the thermal transfer ribbon helps to protect the printhead from direct contact with the abrasive label surface.
5. Don’t use direct thermal/chemi thermal/thermal labels
Using direct or chemi thermal labels? Just don’t. The old argument that this can save time and money has been disproved in practice over the years. Excessive print head wear and the delicate handling of the label after printing are reason enough to persuade most ex DT label users to swap out for the added benefits of using thermal transfer labels for their thermal transfer ribbon printing.
If you have tried the top tips above and are still struggling to get a print to be proud of please give Chris or Sam a call and we will fix it for you over the ‘phone on 01440 712 273