What is ink emulsification? When printing, the ink will be emulsified. What's the matter?

Generally speaking, the emulsification of ink is mainly aimed at offset printing ink, and its unique printing method requires ink to have both hydrophilic and hydrophobic characteristics.

1. What is emulsification? The process of dispersing liquid in immiscible liquid in the form of tiny droplets is called emulsification, and this system is called "emulsification".

Characteristics of ink emulsification:

① Ink emulsification is inevitable. In water-based offset printing, wetting liquid and ink coexist and are immiscible with each other. In the printing process, ink and wetting liquid always contact each other. There are four ways of rolling or extruding ink and wetting liquid:

(2) Ink emulsification is indispensable: in offset printing, the viscosity of emulsified ink is slightly reduced, and the fluidity is improved, which is beneficial to ink transfer. There is water in offset printing, except that some of it volatilizes in the air and some of it enters the paper, and other water should also go somewhere.

If there is no emulsification, excess water will form water droplets attached to the surface of ink, resulting in local ink-free, pen-missing or white spots in graphics and text; Some water drops go up against the ink roller, and the water accumulates more and more, forming a hydrophilic layer on the surface of the ink roller, which leads to ink roller deinking. If there is no emulsification, tiny ink drops will also exist on the water roller, and more and more ink drops will roll up against the water roller, which will reduce the water transfer performance and pollute the wetting liquid. If there is no emulsification, the ink transfer performance will be poor, which will affect the printing quality.

2. Ink-ink balance: At a certain printing speed and pressure, adjust the supply of wetting liquid to make the volume ratio of wetting liquid in emulsified ink be between 15%-26%, and form W/O emulsified ink with slight water-in-oil degree, which can compete with the ink quantity on the printing plate with the least ink supply balance.