June '16

For the Business of Apparel Decorating

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2 0 1 6 J U N E P R I N T W E A R || 57 fabrics, ink manufacturers have intro- duced the high-solids line of chemistry. Fabrics are now being finished with soft- eners that are moisture wicking, anti-mi- crobial, highly stretchable, and designed to retain or release heat. PVC-free inks require strong bleed resistance, stretchability, high opac- ity, adhesion to a variety of fabrics, and color matching systems, and all while still maintaining a soft hand. High-solids water-based ink systems are very different from traditional soft-bases and discharge ink systems. High-solids water-based inks use acrylic resin, which produces very opaque colors. Printing now resembles that of traditional plasti- to a discharge base or color prior to print- ing. The powder needs to dissolve and be dispersed thoroughly into the ink. Once printed, the garment must pass through a forced air dryer, evaporating out all water to allow the chemical bleaching to occur. The result is the raw cotton color, which is somewhere between a vanilla and a brown paper bag color. There are several factors to take into con- sideration when using discharge inks. First is whether to use a zinc formaldehyde or a non-formaldehyde discharge agent. The formaldehyde in the activator can cause some skin irritations, although the formal- dehyde is easily removed once the garment has been washed prior to wearing for the first time. Regardless, this is an important factor to consider. Non-formaldehyde products are usually required when print- ing on youth garments, or when specified by retailers. Secondly, garment selection is critical. Garments must be 100 percent cotton and dyed with a reactive dye. Not all cotton gar- ments will produce great results. Most man- ufacturers have charts that will outline how well the garment discharges. Certain colors like royal blue, Kelly green, and purple do not yield optimal results, while colors like black, red, and navy do extremely well. Lastly, which ink system will achieve the best desired results? Discharge activator can be added to a clear base, and soft bases can be printed on top of the discharged under- lay. Another option is to add activator di- rectly into each of the ink colors. Each color is then discharged independently from the other colors in the graphic. This typically reduces the color count by one or more screens. Some manufacturers even produce an RFU ink that can be used as a soft base or can have activator added to make it a dis- charge ink. HIGH-SOLIDS SYSTEMS As the era of 100 percent cotton garments has shifted to the new age of performance sols as the inks actually bridge fibers or sit on top of the fabric instead of penetrating into the fibers. Due to the nature of the product, each color has to be flashed be- fore printing the next color to avoid "pick up" of the color on the following screens. The downside is that larger-format ma- chines are required with this system due to the increased number of flashes during production. Most systems have high-opacity whites, high-opacity bases, and bleed-blocker bases. Some manufacturers carry RFU colors and others have pigment and base systems. There are also a wide variety of additives that can be added to create different characteristics. For instance,

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