Ink does not light discoloration and fading under the tag printing ink reason sunlight exposure, it will be different degrees of color and brightness changes, the absolute light without changing the color of the ink is not, in strong sunlight effect, all the ink colors will produce different degrees of change. This change can be divided into two types. 1. Fading: In the role of solar ultraviolet ink poor light, lost its bright color logo printing plant in Dongguan, lighter colors become gray. Especially in light color and four-color ink printing when registering yellow and red two colors fade faster than blue and ink fade slowly. 2. color: black ink and print fade contrary, under the effect of daylight color change was darker, and the color is changed, people called this change color. Test exposure time there are many ways, the following describes two commonly used methods: 1, continuous foot ladder test method: using a continuous-foot ladder attached to the PS version dense strip, graded exposure (to start from 80s, every time plus 20S, five times, until the 160s), normal development after reunification, the strip and the PS version use the sun to find out through a predetermined series of Dongguan packaging logo printed on the manual, that is the version of the correct exposure. 2, outlets wedge test method: the copy density test strip attached PS version of the small strip, graded exposure, the normal development of Dongguan clothing tag printing, to find light and dark tone that withered relatively complete network-level exposure time It is the optimal exposure time. In general, positive PS plate should be able to restore the 2% -97% of the network, if the light tone dot loss is relatively small, darkened more white spots lay dead, indicating lack of exposure time; if black specks lost more , while white spots lay dead less, indicating overexposure. Tag printing plant in Dongguan, beyond printing (certified), tag printing from Dongguan City, often beyond packaging products factory provided. Dongguan Chang-ping beyond packaging products plant (www.dgcyp.com) Dongguan, Guangdong, printing paper leaders, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In all walks of life beyond the printing leadership with the staff warmly welcomed the inquiry negotiations to create a better future beyond printing.