For making sure that the UV ink is completely cured by the UV lamp, there’re four detection methods.
The pencil hardness is included in the technical conditions of all UV inks tests. According to this requirement, we can use pencil hardness equipment to test. If it meets the requirements (usually 3-4 hours), it proves that the ink has been fully cured.
There are also solvent resistance items in the technical conditions of UV ink. After the ink is completely cured, the internal molecular structure will change, and the conversion to the double bond will complete the conversion to high curing, and then the ink will form a tight coating. According to the performance of solvent resistance, drop the propionic acid solution on the surface for 2 minutes. While If there is no change, it proves that the ink has been completely cured by exposure to UV lamps.
It is derived from the painting detection method. Choose 500g weight, put a few cotton fibers on UV-cured surface, keep pressing by 2 to 3 minutes, then remove it. If the cotton fiber does not stick to the surface, it means it is fully cured.
The fully cured UV ink has a bright surface looking, no lint phenomenon, no phantom on the edge. It is also one of the important characteristics for knowing that the ink is completely cured by the UV lamp.
In addition, your experience learning from the ink industry, working environment, conditions, equipment integration, application during production, they are valuable technical wealth. Combine your usual experience with test results, It will be more accurate to determine whether it is fully cured.