Phenomenon: the ink is wrong, the amount of resin in the ink is too small; the plastic is not handled well; the film is brittle and hard.
Treatment method: Change the ink for printing the film, and use resin diluent when adjusting the ink; the resin, solvent, and pigment system used for reprocessing should have greater softness on the surface of the film, and it is also related to the adaptability of the film to the ink, that is, it is related to the film. It is related to the greater adsorption of ink on the surface. As far as ink is concerned, polyamide resin and other resins have better affinity for film, but due to the different properties of pigments, the degree of weakening of this effect varies. The treatment of the surface of the film is to overcome its smooth and non-linear defects, so as to increase the adsorption of ink. Long processing time, many times, good adhesion, good processing effect, stronger voltage, better impact effect. The voltage is at least 9000 volts, preferably 12000~15000 volts. The surface can be treated to more than 38 dynes/cm², or add some wax to the blown plastic.
Phenomenon: Tiny holes appear on the printed matter, especially the larger area of the pattern.
Reasons: First, when printing, the ink becomes a very thin transparent layer, and you can see the online line of the plate roller, and the printed product has pinholes (trachoma) of the same size, which is uniform and common in printed products, which is called mechanical pinholes. The second is that due to the ink leveling and poor wetting of the substrate, there are messy pinholes on the printed matter, which are called chemical pinholes.
Treatment method: For mechanical pinholes, it can be solved by appropriately increasing the viscosity of the ink or making the ink dry slowly. For chemical pinholes, when adjusting the ink, do not remove the viscosity too short, so as to ensure the adhesion and leveling of the ink. Therefore, it can be corrected by adding polyamide resin oil or other substances that increase humidity during thinning.