A dispersed mixture of pigments
A dispersed mixture of pigments in a carrier fluid or a solution of an ink in which the final product is a fluid, paste or powder that must be placed on a surface and dried. Writing, marking, drawing and printing compounds are transferred in various ways on paper, metal, plastic, wood, glass, fabric or other materials.
Most of the inks are responsible for conveying information or content, decorating and beautifying or even protection.
Printing ink can be divided based on composition and texture, application, as well as final applications and the type of drying method. The compound composition and texture can be one of the following types: oily compound or pasty compound.
- Solvent compound
- liquid compound (ethylene compound)
- Special compounds
The applications of these inks are in various printing methods, such as relief printing, offset lithography, flexographic or flexible printing, gravure printing, silk screen printing, stencil printing, reproduction, electrostatic printing, and jet printing. The final or intended uses of composites printed in newspapers and magazines, books, advertising and commercial materials, cardboard printing, box printing, paper envelopes, packaging papers, labels, metal containers, plastic containers, plastic films, foils, coatings and sulfones , food packaging materials, sanitary papers or fabrics.
Different drying methods are: drying by oxidation, evaporation, appearance, deposition, polymerization, chemical drying, gelatinization, cold drying, and fast drying compound, growing compounds with ultraviolet rays based on photopolymerization of single members or monomers. It is momentary and instantaneous by the energetic source. If the ink is dried using ultraviolet rays, in addition to reducing pollution in the form of conventional drying methods, the energy consumption is up to 20% of the total energy required to perform the drying method with thermal ovens, which was previously used in printing on paper. and metal were used, decreases.
Ingredients or compound compounds of printing
Inks are a chemical compound that, depending on the printing process, have different fluid properties, which can be in liquid or solid and powder form, and this fluidity depends on the type and ingredients of the inks, which are 4 The main material consists of:
1- Pigment :Pigments are one of the main ingredients in determining the color of composites. These colored grains, combined with resin and solvent, move on the surface in a liquid form, and these pigments made of organic compounds lose their proper chemical structure due to heat and pressure. and should provide suitable environmental conditions for them.
2- Resin: Resin is a chemical substance that, by combining pigment, causes it to move smoothly on the surface and also causes it to stick to the printing surface.
3- Solvents: Solvents are liquid compounds or substances such as water, oils, alcohol, etc., in which the combination of resin and pigment dissolves and dilutes the compound so that the print can be transferred.
4- Additives: Additives are substances such as antifoams, fillers, etc., each of which adds a special feature to be used for different purposes in printing.
The shine and gloss of printing inksدرخشش یا براقی مرکبهای چاپ
The gloss of the printing ink is a measure of its ability to reflect the light shining on it, and it largely depends on whetheThe choice of compound solvent is also important in controlling its brightness. Because it can affect the dispersion of pigments. It is possible to keep the percentage of resin in the composite constant and as a result, the viscosity of the composite printer as well as the characteristics of the composite silane can be controlled. If the solvent is not a true solvent, the compound will have a poor fluidity and as a result will have a negative effect on its gloss.r the ink can create a smooth and even layer on the printable surface and cover its irregularities and imperfections. or not When the ink penetrates into the printable layer, its brightness and shine will decrease. The amount of luster of the printing compound depends on the nature of its color materials, the dimensions of its particles, its shape and surface characteristics, as well as the amount of resin in it and its ability to form a continuous layer on the printable surface. In general, the higher the composite resin and the higher its amount compared to the coloring matter inside the composite, the greater the shine of the composite. The choice of resin can also have an important effect on the gloss of the composite. In fact, the resin changes the ability of the carrier fluid to disperse the pigments, and the better the dispersion of the pigments, the better the gloss of the composite. Also, by increasing the thickness of the composite layers, the surface defects of the printed material will be covered more and the composite surface will be smoother and more shiny.
The choice of compound solvent is also important in controlling its brightness. Because it can affect the dispersion of pigments. It is possible to keep the percentage of resin in the composite constant and as a result, the viscosity of the composite printer as well as the characteristics of the composite silane can be controlled. If the solvent is not a true solvent, the compound will have a poor fluidity and as a result will have a negative effect on its gloss..
Accurate control of ink drying is also one of the factors that must be controlled to achieve the best amount of gloss because if the solvents evaporate too quickly, the ink flow on the printable surface will weaken and its gloss will decrease. On the other hand, if the drying of the ink is very slow and the paper also has an absorbent surface, excessive penetration will take place and as a result, the shine of the ink will decrease.
Additives such as plasticizers can also improve the gloss of the compound by increasing its fluidity and creating a smoother layer for it. Waxes, which are widely used in printing compounds, reduce the gloss of the ink, because they create a non-uniform surface for the upper surfaces of the printed ink layer, which scatters the light incident on it. and creates a matte payment in it.