Infrared radiators can be roughly divided into short-wave (0.8-1.4um), medium-wave (1.5-3.0um) and long-wave (3.0-10um) according to the wavelength. Since the infrared absorption of water mainly has two strong peaks at 3.0um and 4.5um, it is better to use medium wave and long wave. However, long-wave infrared (common ceramic or stainless steel heating tube) has several major disadvantages compared to medium-wave infrared (resistance wire transparent quartz tube): slow reaction speed, poor penetration, and lower power density. Therefore, the medium wave radiator is the best choice. In addition, the medium wave lamp tube can have a gold-plated reflective layer, and its reflection efficiency is higher than that of the general aluminum metal reflector, and it will not be oxidized in a high temperature environment, and there is no concern about the reflectivity reduction caused by dust. Of course, the thermal efficiency of the midwave tube is much better. At the same time, the temperature control is much better due to the fast reaction speed.

However, in some fast drying parts that require high energy density, shortwave infrared still has certain applications. Because its power density can be very large, and the response speed is very fast. These are the things that medium wave lamps cannot do. Although the wavelength of the shortwave lamp does not match the absorption of water and polymer materials, the air temperature near the shortwave lamp is very high. If the distance between the heated material such as paper and the lamp is very close, hot air can also be effective Heating effect. The result is also good. However, for inks and papers that are sensitive to high temperatures, shortwave lamps are not suitable.

In the drying application of water-based inks and coatings, medium wave and short wave infrared drying are both available options. In most cases, medium-wave infrared is the best choice.