Images_Digital_Edition_April_2020

www.images-magazine.com APRIL 2020 images 45 TIPS & TECHNIQUES Water-based printing is not more or less difficult to perform, it simply uses a different set of techniques is the perfect place to start – it will give you exposure to the ink system without the added complication of opacity and flash cure and pick-off. For the ink kitchen, you’ll need a clean and well-lit area with work surfaces that are easy to clean, and a set of digital scales with increments of 0.1g for measuring the small amounts of pigment that you’ll be using. A good storage system for the new pigments and the newly mixed inks is a must, and segregating the water-based and plastisol inks is a necessity. Managing the system How to manage this new system should be considered right at the beginning of the process. This will allow you to get started using water-based ink and not be confused by all the different types available. Most systems operate a base and pigment concentrate system; this means you can create different ink types by just swapping out the base binder. Stick to a core of around 18 pigment colours and, with a recipe system, you can then recreate Pantone colours. Now for the disclaimer: different substrates can affect the colour of the print – water-based discharge uses the shirt to achieve its opacity; high solids acrylic water-based uses the base primer screen; and normal water-based can change hue according to the colour of the substrate! It is always recommended to perform a swatch test before the job goes to press. This should be done using the correct mesh and the correct substrate, with or without a primer screen. Printing with water-based ink does not use a different skill set to the one you are already using. Yes, the ink needs a little more care to prevent evaporation and the clean-up is a little more time-consuming, but it soon becomes part of the routine and the task of cleaning with warm water is nowhere near as bad as breathing in the fumes from solvent ink-remover. On the press the most important thing is the flood. Keep the image wet and you will soon start to lose the panic of ‘Quick, quick, quick, it’s drying in!’ Modern water-based inks can be left flooded for much longer now and I have been able to get 30 minutes from some brands without any blocking in the mesh. Curing water-based ink is not quite as simple as solvent-based curing. With plastisol, you must simply ensure the entire ink film reaches the required temperature, whereas with water- based you must first drive out all of the water and then the chemical binders in the ink can start to do their job. This requires a longer cure – the temperature is important, but even more important is the time. Most water-based inks require at least two minutes inside the dryer, which must be accurate and reliable, as deviations in temperature can be catastrophic to the wash test result. Wash test, I hear you say – what is that? Yes, you must perform a wash test on all inks to ensure you have the correct cure. It is not the customer who complains about a print washing out that you should fear, it is the customer who does not complain but instead tells everyone not to use you because your prints end up in the bottom of the washing machine. Once you’ve nailed the practical side of adding water-based inks to your repertoire, you’ll quickly realise that some simply stunning results can be achieved with them. The iguana print, shown here, used 120 mesh counts with a variety of water-based inks including discharge and high solids, and even some special-effects. This was printed slowly and calmly during a recent seminar in Mexico – the temperature was in the high 20s and we experienced no clogging of the mesh. My final advice on whether to take the plunge into water-based printing is to just do it! Plan the ink room, educate yourself with your chosen ink brand, and have fun. 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 the industry. He is the owner and consultant at Palmprint Consultants, offering practical help and assistance to garment decorators all over the globe. www.palmprintuk.com Water-based discharge printing removes the dye from a shirt to reveal the natural colour of the fibres; these can then be re-coloured using the pigments in the ink Water-based prints generally need at least two minutes in the dryer A white shirt job is the perfect place to start your water-based printing adventure