1. Composition of Ink The pigment is a color, black, or white highly dispersed powder material that is insoluble in water and organic solvents and plays a role of displaying color in the ink.
According to the source and chemical composition of pigment components, organic pigments and inorganic pigments can be divided into two categories: inorganic pigments are composed of non-ferrous metal oxides or some metal-insoluble metal salts, and inorganic pigments can be further divided into natural inorganic pigments (minerals). Pigments) and artificial inorganic pigments; organic pigments refer to colored organic compounds, which can also be divided into natural and synthetic categories according to their sources. Nowadays, organic inks for printing are basically synthetic organic pigments with complete colors and superior performance to inorganic pigments.
The requirements for ink pigments during printing are high, especially the color purity, dispersion, lightfastness, transparency, and the like. Normally, the hue of the pigment of the color ink is required to be close to the spectral color, the saturation is as large as possible, and the pigment transparency of the three primary color inks (cyan, magenta, and yellow) must be high, otherwise the quality of the printed matter will be greatly affected. Regardless of the kind of pigment, it must have good water resistance, can be quickly and uniformly combined with the binder, and has good acid and alkali resistance, alcohol resistance, heat resistance and other properties.
The binder is a chemical substance that acts as a dispersing pigment, imparts proper viscosity, flowability and transferability to the ink, and fixes the pigment on the surface of the print by filming after printing, commonly known as a varnish. The binder can be made using various materials such as dried vegetable oils, mineral oils, solvents and water, and various synthetic resins. The flowability, viscosity, neutral acid value, shade of color, water resistance, and properties of printed materials during the use of the ink are all determined by the binder. The same pigment can use different binders to make different types of ink; the same kind. Because of the use of different pigments, the connecting material is still made of the same type of ink, because the connecting material does not have to change the fundamental performance of the ink, so the quality of the ink is not only related to the pigment itself, but also depends on the connection. material.
The filler is a white transparent, translucent or opaque powdery substance that acts as a filling. Appropriate use of some pigment fillers, can reduce the amount of pigment to reduce costs, but also can adjust the ink dilute, fluidity, but also can improve the flexibility of the ink formulation design.
Additives are materials that are added to improve the ink's own performance during ink manufacturing or printing. When the ink according to the basic formula still cannot meet the requirements for use in certain characteristics, or when the requirements for printing use cannot be met due to changes in conditions, a small amount of additional material must be added to solve the problem.
2, the type of ink According to different methods, the ink can be divided into different types. Commonly used are flexographic printing inks, lithographic printing inks, gravure printing inks, screen stencil printing inks, special functional inks, and the like.
Toppan printing inks can be divided into lead-printing inks, lead-printing inks (copper inks), lead-printing plastic inks, rubber letterpress plastic inks (flexible plastic inks), letterpress inks, letterpress printing inks, etc. according to different characteristics. . This type of ink is basically a penetrating dry type ink. In the printing process, it is necessary to pay attention to the occurrence of ill-adherence such as poor adhesion, powdering, and contamination.
Lithographic printing inks include various offset inks, lithographic iron inks, lithographic photosensitive inks, offset thermosetting inks, and the like. Lithographic printing inks require high color strength and water resistance, and have good flowability and drying speed.
Intaglio printing inks include various gravure inks, engraved gravure inks, gravure plastic film inks, and the like.
Silk screen printing inks include screen printing inks, screen plastic inks, oil-type inks, water-type inks, and the like.
In addition to the above-mentioned several commonly used inks, there is also an ink that can play a special effect, such as micro-particle ink, gold and silver ink, fluorescent ink, magnetic ink, security ink, conductive ink, carbon ink, monitoring ink, Temperature indication ink, color ink, edible ink, etc.
Third, the ink Ink is a kind of fluid substance that is uniformly dispersed in the connecting material, such as pigment particles, fillers, and additional materials, and has a certain viscosity.