Lightfast ink grade and lightfastness test method
Lightfast ink level The lightfastness level is generally divided into 8 levels, with 1 being the worst and 8 being the best. Most printing buyers in Europe require the red and yellow four-color inks to have a lightfastness of 5 or above, and the black and blue inks need to be 7 or above; most of the inks used in Asia follow the Japanese hue, but most of them None of the more lightfast pigments are used, so the yellow and red lightfastness grades are only about 3, but grade 3 is only a general grade. Strictly speaking, it does not meet the lightfastness requirements of Europe, America and other places. In summary, the more vivid colors such as fluorescent ink, yellow, light blue, gold red, orange, pink, purple, green lotus and other hue inks, the light fastness is mostly below level 3; especially with transparent dilute ink The light color inks formulated are extremely lightfast. Lightfastness test method The traditional lightfastness level test method uses blue wool fade as an indicator, so it is necessary to compare the gray proofing ruler and the blue fabric with a visual inspection. It is difficult to have print data support. Recently, the standards of American printing buyers use Lab and xenon light boxes to measure the fading of simulated prints after one year. In addition, the hue of the previous lightfast inks was not bright enough to keep up with Pantone's hue, while the new lightfast varieties are brightly colored and can be adjusted to the colors of the Pantone color book. The users of the system make it easier to formulate lightfast inks. Huai 'an Bst Trade Co., LTD , https://www.bstoral.com