Pearlescent ink features and printing considerations

First, pearlescent ink has the following characteristics:

(1) Large pigment particle size

The commonly used mica titanium pearlescent pigment has a size of 25 μm and a thickness of 0.2 to 0.5 μm.

(2) Transparency affects pearlescent effect The pearlescent effect of pearlescent ink is mainly due to the refraction and interference of incident light. If the transparency of the ink layer is low, the original abundant light will be absorbed and lost. Therefore, when using ink binder or varnish, choose a material with good transparency.

(3) Pigment is fragile

Pearlescent pigments are made of titanium dioxide (or other metal oxides) coated with mica. They are in the form of flakes and are very fragile and easily destroyed.

Second, the issues that need attention in printing:

(1) The back is dirty

When the pearlescent ink is printed, the back surface is particularly prone to sticking. This is mainly due to the large size of the pearlescent pigment particles. In order to increase the fluidity, a large amount of binder is added, so that the ink becomes thinner and the drying time is lengthened. The following measures can be taken to control and solve: First, strictly control the temperature and humidity of the workshop, the temperature is controlled at about 200C, and the humidity is controlled at about 55%. The second is to keep the amount of water as small as possible while ensuring the balance of ink and water. The third is to spray the right amount in the delivery section, but pay attention to the amount of powder spray can not be too large, otherwise it will affect the gloss of pearlescent ink. In addition, it is best not to use dry oil to improve the drying speed of pearlescent ink. If it is necessary to use, use white dry oil, because red dry oil will affect the appearance of pearlescent effect, the amount of dry oil should not exceed 2%.

(2) Suitable for printing on solid color blocks

Due to the large particle size of the pearlescent ink pigment, the ink particles carried on the dots are less. For example, a 2% dot can only carry one pigment particle, and it is difficult to ensure the reproduction of small dots. Therefore, the pearl ink is not suitable for printing. Mesh adjustment products, preferably used in solid color blocks