September '17

For the Business of Apparel Decorating

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2 0 1 7 S E P T E M B E R P R I N T W E A R || 51 Over-print colors: Whatever the ink is, the overprint colors must match the flash and cure profile of the underbase in order to be effective. It doesn't make sense to under cure the overprint colors or over cure the underbase white. A low-cure, low-bleed system is recommended for polyester garments. This ensures the ink will perform as needed without shrinking the garment or fail- ing in durability tests. Low-cure mixing systems, low-cure premixed athletic colors, along with low-cure general purpose whites will allow the printer to print a multitude of fabrics through the same dryer at the same time. No more scheduling around problem fabrics or changing out inks in the middle of a production run. Every type of print is brought into the same temperature range to allow for better production flow and scheduling. PRODUCTION Color rotation: On dark shirts, utilizing the dark to light color rule is the first consideration when printing wet-on-wet. However, other factors may apply. Important Pantone colors or dominant colors in the design may be moved be- fore a flash, or closer to the end of the rotation to avoid pick up or color shift. Smoothing stations: Most underbase grays and athletic whites respond well to smoothing stations. This station may be as simple as a fully exposed solid screen that is printed in the cooling station after a flash. The heat from the flash units, along with the pressure of the squeegee mimics a transfer press. The result is a smooth surface for subsequent colors to be printed upon. Other options for a smoothing station would be a "Hot Head" iron or a heated roller. Flashing: Flash-cure unit settings are very important in the printing of ath- letic goods. The unit should be set to flash with the lowest temperature pos- sible to maintain a production speed. Underbase gray inks tend to flash dry within two seconds at a 180 degrees F surface temperature, whereas the white inks will need three to four seconds with a surface temperature of 180–215 degrees F. Many printers seem mystified on the definition of what constitutes a gelled surface. Once the ink is dry to the touch, it is gelled. If the surface is tacky, it does not mean that the surface is under flashed. In contrast, it is more likely the result of over flashing. It is advisable to use as little flashing as possible; becoming dependent on flash units can wreak havoc on sensitive fabrics. Curing: Obtaining the cure profile of the ink from the manufacturer is of utmost importance. Know the target temperature for all the inks being used before starting the production run. Make sure the cure profiles match between underbases and overprint colors, then set the dryer to hit that mark without over curing. Inks designed to cure low will fail at high temperatures. Next, verify the oven temperature. The best way to verify if the ink reaches the correct curing temperature is to use a thermo probe, also known as a donut probe. To use this equipment, simply: • Place crosshairs of the thermo-probe into the wet ink • Record the temperature in 5 second intervals • Mark corresponding dots onto a temp/time sheet • Connect the dots to view the "cure curve" Monitoring each of these areas and keeping a standard operating procedure in each department will result in consistent and repeatable quality for the ath- letic printer. Remember, each of the areas affect and support the others. This "chain of events" is truly only as strong as its weakest link. Welcome to the PRODUCT HIGHLIGHTS section where each month we offer you resources to enrich and expand your business with great services and products from our advertisers.

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