The use of UV inks in the label printing industry seems to be the consensus in the industry. Whether it is a flexo label or a embossed label, UV ink is used in ink selection. Moreover, when the printing material is extended from the coated paper to the plastic film, it seems that there is no choice but to use the UV ink due to the adhesion of the ink film to the non-absorbent material. Even if it is just the beginning of the label printing industry, the choice of UV ink. Alkali resistance of pigments: Pigments are materials that impart color characteristics to the ink and meet the color requirements of printing. Since the resin of the aqueous ink is mostly alkali-soluble, the viscosity and pH of the ink are precisely controlled, and the pH is generally controlled between 8.0 and 9.5. When the pH is higher than 9.5, the alkalinity is too strong, the viscosity of the ink will decrease, the monotonic speed will be slow, and the water resistance will be deteriorated; when the pH is lower than 8.0, the alkalinity will be too weak, and the viscosity of the ink will rise. The ink is easy to monotonous and will form defects such as dirty plate, paste and blistering. Therefore, pigments with excellent alkali resistance must be used when selecting pigments. Relative density of pigments: When the relative densities of pigments for aqueous inks are very different from each other, pigments with relatively low density are simply floating on them. For example, ink-green inks are often co-colored with pigments such as carbon black and phthalocyanine blue lead chrome. The phenomenon of floating color, hair flowering, sedimentation, etc.; when the relative density of the pigment is too large, the stability of the aqueous ink is damaged due to its simple deposition and agglomeration, such as iron red, chrome yellow, etc., often because the agglomeration cannot be stirred. Before printing, workers should use Dyne or Dyne to check the surface tension of the film material. The film material must have a surface tension of at least 42 dynes/cm 2 if good UV ink adhesion is to be ensured. If the surface tension of the film material does not meet the requirements before printing, the ink adhesion will be poor. Article source address: http:// Swivel bar stools STARWAY INTERNATIONAL HOME-LIVING CO., LTD , https://www.starwayfurniture.com