What are the main components of ink?

Ink consists of pigments, binders, fillers, additives, etc.

(1) Pigment

Pigment plays a role in color development in ink, and it has a direct impact on some characteristics of ink. Pigments are colored, black or white powders with high dispersity that are insoluble in water and organic solvents. According to their origin and chemical composition, they are divided into two categories: organic pigments and inorganic pigments.

①Inorganic pigments are oxides of non-ferrous metals, or some metal insoluble metal salts. Inorganic pigments are divided into natural inorganic pigments and artificial inorganic pigments. Natural inorganic pigments are mineral pigments.

②Organic pigments are colored organic compounds, which are also divided into two categories: natural and synthetic. Nowadays, synthetic organic pigments are commonly used. There are many varieties of organic pigments, and the colors are relatively complete, and their performance is better than that of inorganic pigments.

Dyestuffs are organic compounds, which are soluble in water and sometimes in organic solvents. Insoluble colored precipitates, called lake pigments, can be prepared from certain dyes for the manufacture of printing inks.

The pigments used in printing inks have high requirements, especially color, dispersion, light resistance, transparency, etc. The color pigments are required to have a hue close to the spectral color, and the saturation should be as large as possible. The three primary color inks are magenta, cyan and yellow. The transparency of the pigment must be high. All pigments must not only be water resistant, but also quickly and evenly combine with the binder. The oil absorption capacity of the pigment should not be too large. The pigment should preferably have alkali resistance, acid resistance, alcohol resistance and potential resistance.

(2) connecting material

The binder is the main component of the ink, which plays the role of dispersing the pigment, giving the ink proper adhesion, fluidity and transfer performance, and fixing the pigment on the surface of the printed matter through film formation after printing. The connecting material is commonly known as varnish.

The binder can be made of various substances, such as various dry vegetable oils, most of which can be used to make binders for inks, mineral oil can also be made into binders, solvents and water , and various synthetic resins can be used to make connecting material.

The rheology, viscosity, neutrality, acid value, color, water resistance and printing performance of the ink mainly depend on the binder. The same pigment can be made into different types of ink by using different binders; and the same binder. , using different paints. The ink produced is still the same type of ink, because it cannot change the fundamental properties of the ink, so the quality of the ink depends mainly on the binder, except for the pigment.

(3) Packing

Fillers are white, transparent, translucent or opaque powdery substances. It mainly plays the role of filling, filling the pigment part, and using some fillers appropriately can not only reduce the amount of pigment, reduce the cost, but also adjust the properties of the ink, such as thinness, fluidity, etc., and also improve the flexibility of formula design.

(4) Additional materials

Additives are some materials that are added to improve the performance of the ink itself in ink manufacturing and printing. When the ink prepared according to the basic composition still cannot meet the requirements in some characteristics, or cannot meet the requirements of printing due to the change of conditions, a small amount of auxiliary materials must be added to solve the problem.

There are many additives, such as: desiccant, anti-drying agent, diluent, detackifier, plasticizer, manufacture of wax for ink and so on.