- Reliable, thanks to the proven printing method and high availability
- Service-friendly, thanks to maintenance-free operation
- High quality with clear type face, bar codes, and character heights from 1.6 mm
- Compact and robust devices
Printing principle – thermal printing
In thermal printing, a special, multi-layer ink ribbon is fed between the print head and the component. In this print head, a heating element is integrated for each pixel. The heating element can be controlled from a computer. These heating elements, known as dots, are arranged in a straight line. They dissolve the color layer and, in this way, they transfer the print image onto the component to be marked, line by line.
This process is fast and flexible. However, it requires an appropriate surface finish so that the ink ribbon adheres to the component without any gaps. Many systems are available for soft materials, such as labels, but for hard materials such as polycarbonate, there are very few.
There are three different color layer types. In the thermal transfer printers from Phoenix Contact, resin ribbons which contain an additional separating layer between the ink and PET film are used.
Wax ink ribbons
- Mainly suitable for paper print media
- Create a sharp, clearly legible print image on a rough surface
- Low wipe and scratch resistance
- Used with low print energy
- Suitable for films and plastic surfaces
- Wipe- and scratch-resistant print images with high heat resistance
- Print image is very durable and resistant to solvents and chemicals
- Higher melting temperature than wax ribbons, require more print head heating capacity and a lower print speed
- Transferred to the material with high print energy
- Combine the properties of wax and resin ink ribbons
- Suitable for paper and plastics
- Print image is wipe- and scratch-resistant and provides good heat resistance
- Lower resistance to solvents and chemicals compared to pure resin ribbons
- Can be used in a wide print speed range and are therefore suitable for a variety of applications
- Applied with medium print energy
One of the most important components in a thermal transfer printer is the print head. Er enthält eine hohe Anzahl von Heizelementen, die einzeln elektrisch angesteuert werden können.It contains a high number of heating elements, which can be electrically controlled on an individual basis. They melt the color layer on the ink ribbon and then transfer it to the print medium.
The number or density of the individual heating elements and the temperature changeover frequency determine the resolution of the print image. The print head versions differ with regard to the arrangement of the heating elements.
Flathead print head
Here the heating elements are located a few millimeters away from the edge of the carrier plate. The ink ribbon and the print medium run simultaneously for a short time and are slowed and separated out. These print heads are particularly suitable for printing material off the roll and are used in the Phoenix Contact THERMOMARK ROLL.
True edge print head
In true edge print heads, the heating elements are not located on the carrier plate, but on the thin front side. These print heads can be height-adjusted and are therefore suitable for use on hard materials. This design is therefore used by Phoenix Contact in the THERMOMARK CARD.
Near edge print head
Here, the heating elements are located right on the edge of the carrier plate and the print head is at an angle. The ink ribbon and the print medium are fed apart more quickly, so the demand on the ink ribbons increases. However, by doing so, higher print speeds can be achieved than with flat head print heads.