How does the film material and UV ink do not match?

The UV ink printed on the surface of the film material is more likely to fall off than the UV ink printed on the surface of the paper, mainly because the surface tension of the film material is relatively low, and the UV ink is difficult to firmly adhere to the surface thereof. In general, the surface tension of the film material must be more than 38mN/m in order to firmly bond with the UV ink.

Solution: Before the film material is shipped from the factory, the material supplier must apply corona and coating treatments to increase its surface tension.

Compared to these two treatment methods, the cost of corona treatment is lower, but the stability of the treatment effect is poor, and the corona treatment effect will gradually weaken with the extension of time, especially when the film material is in a relatively high humidity environment. The corona treatment weakened faster when stored. Therefore, in the actual printing process, in order to achieve a good printing effect, it is recommended to perform on-line corona treatment of the film material to be corona treated. Although the cost of the coating treatment is high, the treatment effect is stable and the surface tension is not affected by the time.