Ultraviolet curing equipment is an ultraviolet emitting device specially designed for curing light curing coatings. It can cure coatings composed of prepolymers of free polymerizable unsaturated groups, ethylene molecules that can dissolve them, and photosensitizers (photosensitizers). Generally, unsaturated polymers with photosensitizers are used. Light-curing coatings such as ester resins, unsaturated alkyd resins, and modified epoxy resins. This coating curing equipment has the following characteristics:
1. Disadvantages
Considering the transmittance of light energy, it is only suitable for transparent or translucent light-curing coatings, and other coatings cannot use this curing equipment. Energy efficiency is low. Due to the short curing time, the input power of the ultraviolet bulb is large, and the output power of the ultraviolet light is small, so a large amount of heat loss is generated. Generally, only 20% of the power of the UV bulb is converted to ultraviolet light, 10% visible light, and 70% of infrared and heat energy. Generally, the temperature of the mercury lamp tube wall can reach about 600°C.
The shape of the coated object is required to be simple, and it is not suitable for curing the coated object that is prone to irradiating shadows. Although the aluminum plate can reflect more than 90% of the ultraviolet rays and reduce the shadow to a minimum, the shadowed object cannot be used.
Ultraviolet light bulbs emit strong ultraviolet rays, which can damage the skin and cause eye pain when irradiated directly on the human body. Therefore, this should be paid attention to when designing an ultraviolet irradiation device, and the operator should wear protective glasses. In addition, the ozone generated by the ultraviolet light bulb will corrode the surrounding equipment, and the ozone also has an adverse effect on the human respiratory system. Therefore, it must be considered in the design of the equipment.
The service life of the UV lamp is generally (1500~2000) hours, and the amount of UV light will be reduced by (15~20)% near the later stage, so the reflector should be cleaned regularly.
2. Advantages
Because it is cured at room temperature, objects with poor heat resistance and objects with large heat capacity can be used. UV-curable coatings are essentially UV-cured and do not need to be heated directly. The infrared rays other than the ultraviolet rays emitted from the ultraviolet bulb will increase the temperature of the curing chamber and the temperature of the workpiece. At this time, the temperature of the workpiece can be controlled below 80°C by adopting appropriate measures. Therefore, paper, plastic, wood, etc. can be cured in a short time. The curing of workpieces with large heat capacity is even more energy-saving.
The curing time is generally less than 20s, which reduces the footprint and energy consumption of the equipment.
Ultraviolet light irradiation equipment is relatively simple, and investment and maintenance costs are cheap.
