Feature: Printing Systems
Selecting a Suitable Printing Technique State-of-the-art marking offers many advantages: good permanent readability, an optically attractive image, as well as a high degree of resistance to mechanical and chemical effects. Various printing techniques fulfil these demands. For instance, a laser printer ensures that the marking has a high level of durability. However, this is infrequently used in cabinet building because of the high safety requirements and high investment costs.
Ink-based systems such as labelling plotters are more frequently used. In this case, a solvent-based ink is used, which hardens when the solvent vaporizes. The principle is simple, but has the disadvantage that the labelling pens simply dry out when the solvent escapes. Ink-based systems contain solvents that ensure that the printing ink has the required viscosity. As a result of vaporization, with or without applying heat, solvents such as alcohol, oils, or water are dissipated to the environment and the ink dye itself remains as a solid on the substrate. This procedure can barely be controlled, as vaporization depends on additional factors.
Ambient temperature, air humidity, and the time between the printing operations play a decisive role. Continually regulating the printing process costs a lot of time and also results in high costs in operation. Not only this, the dried out pens and print cartridges are damaging to the environment.
The “Bluemark” printer also uses ink jet technology. The system developed by Phoenix Contact does not use solvent-based ink, but rather a solvent-free labelling fluid. UV light, utilizing LED technology, is used to cure the fluid. As a consequence, the labelling is resistant to solvents, smearing, and scratches. Thus this printing system is designed for high labelling volumes.
Thermal Transfer Printer as Flexible Alternative
The thermal transfer printer is an alternative to solvent-based marking systems; this is a printing technique where there is direct contact with the marking material. A thermal printing head is the central element, which can be simply considered as a print head with a pin cushion. The distance between the heating elements (needles) defines the print resolution. Today, 300 dpi (dots per inch) is standard, and even font sizes of 0.5 mm are possible.
The heating elements are very quickly heated up and cooled down again. The ink is applied to the print medium where the heating element comes into contact with the ink ribbon: smear-proof, insensitive to alkalines and acids, as well as resistant to temperatures up to 150 °C.
The advantages of this system, which operates with a fixed ink colour, are quite clear: low purchase costs, compact and mobile, always available.
Thermal transfer printing is used nowadays to print labels and shrink tubing. In this case, generally flat roll materials are processed. The flat material can be simply transported and processed in the printer.
The roll material is primary suitable for mass processing of marking materials. The roll material is not flexible enough for small series, because the roll has to be changed each time the size or type is changed. To also be able to use the advan- tages of thermal transfer printing for these types of applications, Phoenix Contact developed the “Thermomark card”, which processes two card formats:
• Material in the 75 x 120 mm format for marking materials with raised contour – for example to label terminals • Flat material in the 115 x 165 mm format as punched version to mark conductors, cables, and equipment at a favourable price
Before starting, the material is placed in the adapter magazine. In just 8 seconds, a card with up to 120 markings is com- pletely printed.
Conclusion
Professional marking systems for the industrial environment operate with quite different materials, which fulfil different requirements depending on the application. Software programs form the basis for simple and direct input or for user-friendly transfer of labelling data from a CAE system. In each case, software, printing system, and marking materials form a closed system, in which all of the parameters are harmonized and coordinated with one another. Users not only save time and money, they also profit over the long term from high-quality marking.
Phoenix Contact For all the most up to date news and products visit
www.thepanelbuilder.co.uk May 2012
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21