The non-drying label printing ink of three big reasons and solutions
a, lower the surface tension of the membrane material
root cause: under normal circumstances, in order to guarantee the normal printing, the surface tension of the film class material must be above 38 dyne. In order to make the printing ink adhesion, must be 42 dyne.
solution: if off the ink in the printing process happening, can use the dyne pen test the surface tension value of the material. If less than the above standard, the proposal chooses online corona or coating of bottom oil way to increase the surface tension of the thin film material, easy to achieve better actual effect printing ink adhesion. If there were no conditions by using this two ways to solve the above problem, also can choose low surface printing ink to try to solve.
2, UV curing poor
root cause: it has to do with the UV printing ink curing actual effect has great relevance. If the output power of the UV lamp is not enough, or printing speed too fast, will appear & other; Fake dry & throughout; Condition, this kind of situation is very easy to cause the ink. The so-called & other; Fake dry & throughout; Is refers to the surface of printing ink is drying/curing, but inside is not completely drying/curing. Here should be a special show that this kind of situation caused by the drop in the large area of printing ink develops in field pattern. This is because of the large amount of field pattern in ink, ink layer inside is not so easy to cure completely. In addition, sometimes at the same time, printing printing ink is only one color ink is relatively obvious, the most commonly used is black out ink printing ink.
solution: check the UV lamp is beyond the service life of rating, if out of life, must be changing a bulb. If UV lamp in the normal use of time, so the output power of the UV lamp is not enough, it should be moderately can improve the output power of the UV lamp, or reduce the rate of printing.
3, printing ink additives too much
root cause: the temperature will affect the consistency of printing ink and viscosity. The temperature is relatively cold winter in the northern region. Printing process will encounter in the printing ink thicken, viscous and bad ink problem. So many operators can choose to add ink oil way to improve the mobility of printing inks. But oil ink dosage used wrong, it is very easy to cause the ink.
solution: normally, add ink 3% ~ 5%.