UV glazing actually has many factors. Due to different substrates, different types of inks, different glazing methods and equipment, and different characteristics and requirements of printing products, the composition of UV varnishes is different, so they appear. Coating failure and imagination are not the same, this section will be the most widely used paper coating glazing analysis, for reference.
First, the brightness is not good, poor gloss
1, the phenomenon of failure
1 Varnishes have low viscosity and the coating is too thin.
2 paper is rough, poor smoothness, absorption is too strong.
3 The anilox roller is thin, and the coating roller has less oil supply.
4 Ethanol and other non-reactive solvents are excessively diluted.
5 Print surface ink does not dry.
6 ink repels varnish, causing hair and unevenness.
7UV Varnish is poor in quality and its brightness is not good.
8 Low temperature and high humidity.
9 aging of the light source, varnish curing is not complete.
10UV Varnish is mixed with impurities and is not clean.
2, elimination method
1 Appropriately increase the viscosity of UV varnish, increase the coating amount, and do not affect the evenness and smoothness of coating.
2 The paper is too thick and should be coated with a water-based primer or a solvent-based primer.
3UV before the ink needs to be fully dried.
4 If the cause of the ink is to cause oil-repelling, hair growth or affect the adhesion of varnish and ink, it should be coated with a primer.
5 The UV varnish must be fully cured. Replace the lamp if it is found to be aging.
6 The addition of non-reactive diluents (such as ethanol, ethyl acetate, toluene, etc.) should be minimized so as not to affect the complete curing of the UV varnish.
7 Select UV light oil with good leveling and high gloss.