Critical Control Points, Part 3

Discover the drawbacks of high-temperature flashing and why you should verify platen location from press to press.

In this final installment of my series on critical control points, I will focus on two production issues that all garment printers should be aware of. In the first part, I'll discuss the importance of temperature control when flashing-curing prints. Then I'll wrap up by highlighting a platen-alignment issue that might be present in your operation if you use more than one carousel press. Flashing temperatures Flashing temperatures often are allowed to stray from their optimum settings in the heat of a busy production schedule. When it seems there aren't enough hours in the day to knock out the volume of prints required, flash-temperatures inevitably tend to rise and problems begin to show. Most printers decorate garments with a "more is better" mentality. They figure that if they turn up the temperature of the flash-curing unit, they can print faster and meet the day's production quotas for the facility or that press. But in the long run, altering standard flash settings will lead to more troubles than benefits. The optimum setting for most flash units is one in which the underbase being flashed just reaches the temperature where it is dry enough to overprint with a minimal amount of after-flash tack. This setting changes depending on several variables, including the type of flash unit you are using, the type and amount of ink you are attempting to flash cure, and the distance of the flash unit's heat source from the surface of the ink film. Few printers place the required amount of emphasis on flash curing. They simply see it as a minor step in the printing process. But if the correct flashing parameters are not maintained during production, the problems that can emerge may include decreased productivity, increased reject rates, and intercoat-adhesion issues that surface when the printed garments are subjected to wash testing. Many printers set the flash unit at its highest output level--more than 1000

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