Because of the wide range of uses and low input screen printing process, other printing methods are difficult to print substrates, the use of screen printing, so the screening process has been developed rapidly in recent decades. Bringing such excellent features of the screen printing process, in addition to the diversity of printing equipment, there is multi-functional, multi-purpose photo emulsions. Therefore, the correct choice and use of photo emulsion than the choice of other printing methods (gravure, letterpress, lithographic, flexographic) is more important. The selection and use of photo emulsion screen printing ink and other types of ink are the same with pigments, resins, solvents, additives mixed, and ground.
1. According to the drying method can be divided into.
Steam drying type - through the solvent evaporation to make the ink into a film adhesion method.
Oxidation polymerization type - through the oxidation reaction to make the ink into a film adhesion method.
Two-liquid reaction type - through the two-component chemical reaction so that the ink into the film adhesion method.
Ultraviolet curing type - the chemical reaction caused by ultraviolet light irradiation makes the ink form a film adhesion method.
Different drying methods of photo emulsion can bring different gloss, different resistance (mechanical resistance, chemical resistance, weather resistance) of the printed ink film, the use of different drying equipment, resulting in different costs, so users need to choose carefully.
2. According to photo emulsion linkage material type can also be divided into a variety of types, but different ink manufacturers choose different resins, which can be broadly divided into epoxy resin class, polyurethane class, polyester class, vinyl glass, acrylic glass, rubber class, etc. Only clear substrates of different materials can choose different resin types of ink, in order to avoid the consequences of bad adhesion caused by ink errors. Not clear material substrates, it is best to determine the choice of ink after the printing test.
3. Different types of ink using their manufacturer to provide matching thinner, mainly because a variety of thinner to a variety of different resin types of ink have different solvency, in order to avoid adverse printing effects.