Since screen printing has a very wide range of applications, the requirements for screen printing inks are also relatively strict. Therefore, in order to meet the different requirements of printed products for inks, the following tests should be conducted on screen printing inks.
① Adhesion Tests are conducted to determine the degree of adhesion of inks on different materials.
② Flexibility Tests are conducted to test the adhesion strength of inks to substrate materials.
③ Kneading resistance Kneading resistance is mainly a strong test on the printed surface of materials such as cloth, paper, and film to test the degree of adhesion and firmness of inks to the substrate materials.
④ Abrasion resistance After the printed surface of cotton cloth is exposed to sunlight, the cotton cloth is rubbed a certain number of times to test the degree of contamination of the cotton cloth.
⑤ Weather resistance Weather resistance also includes light resistance. Weather resistance usually places the printed material outdoors for tests such as wind, sun, and rain to test the discoloration and fading degree of the printed material pigment and the decomposition and discoloration degree of the printing ink film.
⑥ Heat resistance and cold resistance Because some printed products need to be used at different temperatures. Therefore, some printed materials need to be processed at high temperature after printing, while some printed materials need to be processed at low temperature after printing. Heat resistance and cold resistance experiments are used to test the degree of change of ink at different temperatures.
⑦ Hot water resistance The hot water resistance test usually adds a certain amount of warm water to the printed surface per unit area and stirs it for a certain period of time to test the degree of water pollution. In particular, the degree to which the pigment in the ink is soluble in water is observed to determine whether the ink is suitable for printing on edible utensils and toys.
⑧ Oil resistance Oil resistance refers to the adaptability to grease, machine oil, etc., which is different from solvent resistance.