Pearlescent ink features and printing precautions

Pearlescent ink features

(1) Pigment vulnerability

Pearlescent pigments are made of titanium dioxide (or other metal oxides) coated with mica. They have a flake-like structure and are very fragile and can easily be destroyed.

(2) Large particle size

The commonly used mica titanium pearlescent pigments have a size of 25 μm and a thickness of 0.2-0.5 μm.

(3) The effect of transparency on pearlescent effect The pearlescent effect of pearlescent ink mainly comes from the refraction and interference of incident light. If the transparency of the ink layer is low, the originally abundant light will be absorbed and lost. Therefore, when selecting the ink binder or varnish, choose a material with good transparency.

Use caution

(1) Suitable for the printing of solid patches

Due to the large particle size of the pearlescent ink pigments, the number of ink particles carried by the dots is small. For example, a 2% dot can only carry one pigment particle, and it is difficult to ensure the reproduction of small dots. Therefore, the pearlescent ink is not suitable for printing. Mesh tune products are best used for the printing of field patches.

(2) The back of the dirty phenomenon

The printing of pearlescent inks is particularly prone to back-face smudging. This is mainly due to the large size of the pearlescent pigment particles. In order to increase their fluidity, a large amount of binders have been added, thus making the ink thinner and the drying time longer. Can take the following measures to control and solve: First, strictly control the workshop temperature, humidity, temperature control at about 200C, humidity control at about 55%. The second is to keep the amount of water as small as possible while ensuring the balance of water and ink. The third is to spray powder in the delivery section, but it should be noted that the amount of dusting can not be too large, otherwise it will affect the gloss of pearl ink. In addition, it is best not to use dry oil to increase the drying speed of pearlescent ink. If it is necessary to use it, use dry white oil because red dry oil will affect the appearance of pearlescent effect. Dry oil should not exceed 2%.