Application of pearlescent pigments in gravure printing

Pearlescent pigments have been available for more than 70 years and have a long history in the printing industry. Pearlescent pigments have been widely used in paper printing, different types of printing processes and products, such as lithography and gravure printing.

    The products are mainly used in paper printing such as soap packaging paper, cigarette case, cigarette holder, greeting card, wallpaper, food packaging paper, etc.; film printing, such as PET, PE, OPP, PS, etc., because pearlescent pigments are widely used, now mainly introduce pearlescent The use of pigments in gravure printing.

    In gravure printing, pearl powder can be directly added to the printing and diluted into the agent. The amount of pearl powder used can be added according to the customer's requirements. Up to 30% can be added. The printing manufacturer can purchase the pearlescent pigment and mix it directly into the printing agent.

    Pearl powder is an insoluble pigment. It needs to rely on a very good dilute agent to make the pearl powder all wet and dissolve, and the effect can be perfect after printing.

    1. Mixing of pearl powder and thinner

    Pearl powder is a kind of crystal powder. When it is blended with a thinner, if it is improperly treated, it is easy to bond into a spherical shape, which leads to the formation of pinholes in printing and poor printing gloss. Therefore, it is very important to use a good dilute. In order to prevent the pearlescent pigments from sticking to each other and to form a small spherical shape, the desired pearlescent powder must be weighed first, and then slowly added with a thinning agent to ensure uniformity of the pearlescent powder in the thinner, such as printing viscosity is too high, Add some diluent as appropriate.

    If a color pearl effect is required, a 0.5-1% ordinary color ink can be added to the adjusted pearl powder to achieve a colored pearlescent effect.

    Pearlescent ink sometimes shows deposition during use. It uses a circulating cylinder to operate at low speed to keep the pearl powder flowing. At the same time, the ink pump is used to guide the ink to the ink tray for printing. The remaining pearl ink is then used by the pipeline. Flowing back into the ink tank, this device prevents the precipitation of pearl powder while maintaining color stability. The depth of engraving of the plate roll also has a lot to do with the printing effect. If anti-settling agent is added to prevent precipitation, the ink concentration will increase, the fluidity will be reduced, and the printing requirements will not be met. This problem is worthy of the use of the manufacturer.

    2. Selection of pearl powder

    As mentioned above, the size of the pearl powder has a great relationship with the depth of the printing plate. If the depth of the plate is not enough, only the ink will be transferred during printing, and the pearl powder will remain in the ink tank. , resulting in more and more serious precipitation and common ups and downs.

    Before ordering pearlescent pigments, you must understand the pearlescent effect of the product to determine which type of pearlescent powder is most suitable.