Thermal Transfer Ribbon Guide
Thermal transfer ribbons consist of a protective back-coat, a film and ink rolled onto a hard cardboard core of various sizes and dimensions. The type of ink used varies for different label materials used and they are available in a multitude of colours – although black is by far the most used colour – especially when printing barcodes. The ribbon protects the print head from abrasion. This abrasion would come from the contact of the label surface directly onto the print head surface – so it is preferable to use a ribbon that always covers the entire label width. Different label materials would have different abrasive effects on the head, but having the ribbon between the label and the print head avoids much of this abrasion.
To better understand the print process, please note the following diagram:
Heat is generated from the print head through tiny thermal elements that run the width of the print heads contacting surface. Wherever the desired printing is to take place, the corresponding elements are activated and heat is produced at these points. The film provides thermal conductivity and so the heat is transferred through to the ink side of the film – melting it onto the surface of the label – whilst the film prevents the ink from smearing. The film is left clear at the point of printing – so the ribbons can only be used once.
Thermal transfer ribbons can be spilt into three basic categories:
The Most Cost Effective. Generally used for paper labels or porous label stocks. Does not produce a stable image. Can be easily smudged on gloss or hard surfaces.
Wax / Resin
Generally used on treated (gloss) paper labels. Produces a harder stable image and not easily smudged.
Generally used for Synthetic labels. Produces a very stable image. The ink actually becomes part of the labels. Certain brands of resin ribbon also have chemical or heat resistance.
Buying the right ribbon for your printer:
So now you know what type of ribbon you need for the labels you wish to print – now you need to order the right size that will fit your printer. Unfortunately, different printer models and brands often require different ribbon sizes as they are restricted in the physical size of the roll that they can handle; for example, a small plastic desktop printer may only take a 70-90 meter roll of ribbon – where as an industrial printer can take a 300-450 meter roll. Always consult your user manual or a brochure for your printer to ensure you know the right diameter roll that can be used.
Ordering the right width of ribbon just makes economic sense. Sure, you can order the full-width ribbon and use this on all your label sizes, but the wider the ribbon the more it will cost – so you end up wasting money. Thermal Ribbons come in a variety of widths – simply order the next size up that will cover your label width and you will save money; for example, a label that is only 55mm wide will only require a 60mm wide ribbon. Considering that most printers can take an 110mm wide ribbon that’s a huge saving!
This is an area that lots of people get wrong – ordering the wrong core size! Some desktop printers require a smaller core than the standard 1″ (25mm) core that many use; (they actually need a 19mm core). Make sure that you check your printer user manual before ordering – these smaller core printers also often require a notch in the core roll – so they can lock onto the spindle; without this, they fail to print properly and you will have nothing but issues.
CSO or CSI ???
What’s this CSO CSI all about?? Quite simply, the ribbons can be supplied rolled with the “Carbon side Out” or “Carbon side In”. This means that the ribbon has the ink on the outside or inside of the rolled film. This is also very important to get right as most printers will only work in one direction. In general CSO is the most widely used format but again, check the manual or brochure – or call Intermax assistance.
Advantages of Thermal Transfer: