There are several main factors that affect the degree of ink drying on flex printing machine

(1) Ink layer thickness

This has a direct relationship with the selected anilox roller. The more the amount of ink transferred by the anilox roller, the longer it takes for the ink to dry. This effect may be less noticeable at low speed printing, but it will be manifested during high speed printing. This will lead to a series of problems such as smashing the product color and cracking the ink layer. This will directly affect the production efficiency of the product, and the advantage of high efficiency of flexographic preprinting production will be lost.

(2) Printing machine drying performance

Flexo preprinting is divided into two types: unit type and CI type. The drying methods of the two types of printing machines vary greatly. The unit type flexo printing machine is an drying unit for each color group, and the spacing between the color group and the color group is large; the CI flex printing machine has a small spacing between the color group and the color group. The surface is dried for the next color group to complete the overprinting, and after all the inks are printed, all the inks are thoroughly dried in the main oven.

For this reason, under the same speed conditions, the time required for the CI flexo ink to dry between the colors is very small. When the multicolor overprinting is performed, if the front color ink is not well dried, the back color ink will appear when the color is overprinted. When the front color ink is taken away, it is a problem of poor overprinting or cross color.

(3) Drying performance of the ink

The printing suitability of the ink should match the printing machine, especially the running speed of the printing machine. Otherwise, the drying speed of the ink will be too fast, which will easily cause the dry plate problem. If the ink drying speed is too slow, the paste problem will be caused. Although there are printing auxiliaries such as quick-drying agents, slow-drying agents, and pH stabilizers, excessive use of printing auxiliaries tends to cause other printing problems. It is recommended to improve ink printing suitability through ink suppliers, supplemented by printing auxiliaries.

With many years of experience, DH (see DH product) has developed a variety of efficient drying ovens for unit or CI flexo presses. Combined with hot air recovery, air volume adjustment and other functions, it can maximize drying efficiency and reduce energy consumption.