Optimized UV LED curing in inkjet printing applications

 
Based on proven ease of use and process efficiency, UV LED technology is a superior choice for industrial UV inkjet printing. The objective of this work was to improve surface curing of UV inks. In order to achieve this aim, the effect of intensity and wavelength of the radiation on the curing process was evaluated. Furthermore, curing with different combinations of UV LEDs with emissions at 300nm, 365nm, 390nm, and 420nm was examined. The choice of wavelengths has a crucial impact on process speed and product quality. Conversions of samples cured with 300nm LEDs were about 64% higher than those for samples cured with nearly 15-fold more powerful 420nm LEDs. Highest conversions were achieved by combining 300nm and 390nm LEDs. Abrasion resistance of the print can be increased by 60% by combining 300nm and 390nm wavelengths instead of using only 390nm LEDs with comparable light intensity.