TIPS & TECHNIQUES 104 images JANUARY 2020 sorting and organising workflow greatly decrease the time required to image a screen. Some units even have a built- in exposure unit so the screen can be imaged and exposed in one operation. Wax systems These use a solid block of UV-blocking ink and melt it down to a liquid that passes through the print head. This can give resolution up to and above 85lpi with virtually no dot gain as the ink solidifies on contact with the cold screen. These systems are very popular and have revolutionised many print shops with their accuracy and high image resolution. The removal of the film process, along with no need for glass or vacuum, has eliminated the risk of contaminants such as dust and other particles getting onto the film. This greatly reduces, and in most cases eliminates, the ‘pin-hole’ phenomenon that has plagued all printers, whereby the shadows of small biscuit crumbs and dog hairs that were not part of the original design somehow make their way onto your lovingly prepared screens. Laser exposure systems These are the emerging technology. This process is in widespread use in the graphics industry, Tony Palmer has been in the garment decoration industry for over 30 years and is now an independent print consultant working closely with print shops to get the most from existing processes and techniques. Tony is passionate about keeping and enhancing production skill levels within in the industry. He is the owner and consultant at Palmprint Consultants, offering practical help and assistance to garment decorators all over the globe. and the units are now becoming affordable for the garment industry. The process is almost opposite to what we currently associate with making a screen. Traditionally we print or create a shadow (reversed) image and shine UV rays onto light-sensitive emulsion. Where light hits the emulsion it becomes water- resistant and where light is blocked (by the shadow image) the emulsion stays water-soluble. Laser systems use only UV light in the shape of a targeted wavelength laser that can shine UV light in only the places where we need it and turn it off in the places that do not need exposing, all in super-high speed and giving high-resolution images. The major advantages of this system are the complete lack of consumables – no ink, no wax, no film – and the fact it doesn’t require a separate exposure process. With the laser head’s long (10,000 hours) lifespan, these systems also promise an excellent return on investment, especially if you image two screens at once. Revolutionary introduction All systems have small advantages and disadvantages. For example, each emulsion has a specific wavelength that must be compatible with the exposure system you are using, and the surface of the emulsion must also be receptive to the inkjet brand’s ink to avoid any spread of images. Long periods of inactivity can also risk the usability of some print heads. The Douthitt system is a wax printer system that delivers high accuracy and image resolution With the laser head’s long lifespan, these systems promise an excellent return on investment Nevertheless, the introduction of CTS has revolutionised screen- making departments. The repeatability of images without the distortion associated with film, and the computer-placed positioning of images using a clamping system along with the removal of any contaminants on a carrier film, have all greatly improved the consistency of one of the most important parts of the garment decoration process. The throughput of a print shop’s stencil department is critical to the business’s commercial success – if it is too slow and can’t keep up with the presses it can easily lead to a bottleneck. The predictable and consistent imaging of stencils is an important part of this process. A system that can eliminate downtime due to faster set-up times can make any investment worthwhile in itself. We only make money when the squeegees are moving, so the less time spent setting up a job and the more time spent printing is always a positive move. The MHM Spyder from MHM Di rect GB is specifically designed for use with MHM automatic presses Saati’s 6060 VF direct laser CTS system