There are eight factors that directly affect the slow drying of printed labels, here Label Source explains as below：

1.Ambient temperature: Low ambient temperature or high humidity will slow down the drying of ink.

2.Ink properties: Generally speaking, inks made with organic pigments dry slower than those made with inorganic pigments, thinner binders dry slower than thicker binders, and inks with higher oil content dry slower than those with lower oil content.

3.Diluents and thinners: Both diluents and thinners have the property of inhibiting ink drying, so they should be added in small amounts.

4.Paper properties and structure: If the paper is acidic, the ink dries slowly. A rough paper surface, loose structure, high permeability, and low sizing will promote ink drying, while the opposite will slow down the drying process.

5.pH value of dampening solution: Low pH value of dampening solution: The concentration of hydrogen ions (H+) in the dampening solution is very high, which will cause a displacement reaction with the metal salts in the drying oil, thereby inhibiting the drying of ink on the paper surface.

6.Printing Moisture: In the label printing process, if the printing plate has too much moisture, it will not only cause the paper to absorb too much water and swell, but it will also form water-in-oil emulsion ink, thus affecting the drying of the print.

7.Adding too much desiccant: Adding too much desiccant will make the ink coarse, the printing plate dirty and blurry, the halftone dots enlarged and deformed, with fuzz and barbs, and the print difficult to dry.

8.Over-stacking of printed sheets: If the printed sheets are large and the paper surface is smooth, and the stack of paper is too high, it will be difficult for the air to come into contact with the printing ink, which will inevitably cause the ink to dry slowly.

Label Source is a high-tech enterprise specializing in the development and production of Inline Flexo Press and Full-Rotary CI Letterpress Label Printing Machines, as well as full-servo roll-to-roll single-color, two-color, and multi-color multi-functional precision screen printing equipment. The company integrates R&D, production, sales, maintenance, technical support, and upgrades for self-adhesive label printing machines, serving customers both domestically and internationally with professional ethics and dedication.