Printing industry diy pearl powder application

The printing industry is one of the main areas of diy pearl powder applications, including pearlescent ink printing products, including packaging, publications, home decoration materials or clothing, and even ceramics and home appliances. People's aesthetic experience naturally accepts and affirms this effect. This is the main reason why pearlescent pigments are used to improve product quality and decorate life.

Pearl printing can be performed in the main printing methods such as offset printing, gravure printing, flexo printing and silk screen printing. Through the other surface finishing methods, the above light and sweeping gold can also obtain a unique gloss effect. According to the specific process requirements and the characteristics of the pearlescent pigments, the inks are adjusted accordingly to achieve a satisfactory pearlescent effect. In addition, care should be taken to coordinate the relevant process parameters.

Compared with traditional pigments, pearlescent pigments have great differences in chemical composition and structure, as follows:

(1) The material content is relatively large: in the case of offset printing, the granularity of ordinary pigments is generally 0.02 to 0.08 μm, the carbon black is 0.2 to 0.7 μm, and the size of pearlescent pigments used for printing is 5 μm to 25 Micron is much higher than the former. Larger grain sizes present certain difficulties in printing transfer.

(2) Flaky structure: This structure is determined by the shape of the mica core and is also the basis for expressing the pearlescent effect. But it is inconvenient for the transfer of printing. In the preparation of the ink, it is particularly impossible to apply high speed, large shearing force or excessive rolling operation, otherwise the pigment will be destroyed.

(III) Surface morphology: The microscopic surface of the pearlescent pigment is composed of many grooves, so that it has a relatively high surface energy.

In order to avoid the above-mentioned features causing trouble in actual printing, Kuncai has summarized some practical and effective experiences on the basis of years of research for printing inks and printing manufacturers:

Pre-wetting of the pigment: The pigment should be wetted before it is mixed into the ink. The solvent used for wetting should be compatible with the ink system. Good wetting allows the pigment to be evenly dispersed into the ink, which is the basis for high quality pearlescent printing. Wetting also overcomes the "dusting" phenomenon of dry powders during dispersion.

Dispersion of pigments in ink: pearlescent pigments have good dispersing ability. Generally, low-speed stirring can be used in low-viscosity inks. Try to avoid the use of equipment such as three-roller, high-speed mixer or ball/bead mill, which causes the pigment to break. For tarnishing, it is recommended to mix the pigments in the final stage of ink production. When using a disperser or a high speed mixer, the mixing time per batch should be kept constant and shortest.

Use a good transparency ink medium: whether it is ink color or binder, transparency is an important factor affecting the pearl luster of the ink.

The distribution characteristics of the pigment determine the effect: the more the pearlescent pigment is distributed in the printed coating, the better the uniformity, the better the pearlescent effect; the other is also important: only when the pigment chip is aligned with the surface of the substrate Get the ideal pearlescent effect.