How to solve the problem of slow solidification of uv ink?

   If the uv ink can be fixed well, it will dry from the inside to the outside. In this case,

although the ink surface can resist static pressure after solidification, the ink layer

cannot withstand friction. Ordinary ink is mainly dried by chemical reaction.

The oxidation and high polymerization of ink turpentine are enhanced by desiccant,

which is an important component of ink. If the UV ink is not dry enough to resist

the pressure of the next printing color, the paper cannot print the second color.

Worst of all, if the ink takes a long time to dry, the medium containing rosin will

penetrate into the paper too much and the ink film lacks the ability to bind the pigment,

which may cause white deterioration. Operators should know that this kind of trouble is

very complicated, and it is based on unbalanced factors such as ink, paper,

and printing conditions.

1. Temperature, since drying is a kind of chemical reaction, temperature can affect its

drying speed. Control the temperature of the paper or printing room, if it is under

abnormal conditions. From 60°F v less than 0°F is ideal.

2. Desiccant, if the amount of desiccant in the UV ink is not enough, pay attention to

its characteristics and amount, and add some desiccant to the ink. But adding

too much desiccant is not recommended.

3. Control the wetting water, too much wetting water will cause this trouble.

4. The humidity of the paper, too much moisture on the paper will slow down

the drying speed. In this case, a stronger desiccant is best.

5. The PH value of the sink, too much acidity (low PH) in the wetting water will reduce

the activity of the desiccant. A suitable range of pH is from 5.0 to 6.0. At a minimum,

the pH should remain above 4.5.

6. The PH value of the paper. For the same reason as above, it is very dangerous if

the PH value of the paper is too low. When the pH of the paper is too low,

such as below 4.5 for non-powdered paper and below 6.0 for powdered paper,

it is necessary to use a strong desiccant or a larger amount of ordinary desiccant than usual.

7. The composition of the sink liquid. It is known that some synthetic chemicals in

the sink liquid can have adverse effects on the drying speed.

8. Add varnish, if you find trouble after finishing all printing colors,

you have to use varnish to print again.