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UV curing light source has no thermal radiation and higher safety. In addition to generating ultraviolet radiation, gas discharge light sources also generate a large amount of visible and near-infrared heat loss during the discharge process. In order to maintain the vapor pressure of the discharge material inside the lamp, the surface temperature of the UV LED curing light source is very high (the surface temperature of the discharge tube reaches 700-900 ℃). During floor construction, especially in indoor environments, volatile flammable and explosive gases may be generated, which can easily cause safety accidents such as combustion or explosion when exposed to high temperatures such as mercury lamps. But it is a 'cold light source' that emits light without infrared radiation, and the heat generated by the chip is exported from the back substrate through a heat dissipation structure design and cooled by reasonable cooling facilities. Therefore, the surface temperature of the ultraviolet curing light source is low, and there will be no heat accumulation on the illuminated surface, which can avoid such accidents.

So far, the center wavelength emitted by UV-LEDs with high radiation efficiency is above 365nm. Therefore, when selecting a coating formula that matches the curing system, it is necessary to choose a photoinitiator with a large absorption spectrum at long wavelengths. The most commonly used curing system using mercury lamps is photoinitiator 1173 (2-hydroxy-methylphenylpropan-1-one). The absorption spectrum of the initiator has a large absorption peak at around 300nm in short wavelength, but the absorption rate is very low near 380nm in long wavelength. Therefore, initiators are not suitable for curing systems. When using a curing system, a photoinitiator with a longer absorption spectrum should be selected, such as photoinitiator 819 phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide.

The 'effective UV utilization efficiency' can be used to evaluate the compatibility between the curing system and the photoinitiator. This parameter comprehensively considers the radiation efficiency and the absorption spectrum of the photoinitiator, without taking into account the actual power of the UV curing light source, which helps to objectively evaluate the overall efficiency of the application system. It can be used not only for curing systems, but also for other UV applications.

Of course, the efficiency of photoinitiators in UV curing reactions can also affect the overall efficiency evaluation, but the proposal of effective utilization efficiency provides a reference for the selection of schemes related to photoinitiators. The comparison between different photoinitiators requires more quantitative determination of their absorption spectra, which requires further research work.

Curing, as an efficient and environmentally friendly green technology, has been rapidly developed and promoted in recent years. Especially with the growth of China's economy, there is a huge market potential for the application of ultraviolet curing light sources for curing. Under this development trend, there is an urgent need to develop a high-power ultraviolet LED curing light source curing system to meet the application requirements. In response to the technical difficulties in high-power module packaging, a sandwich packaging structure using copper plates and AlN plates has been invented, which effectively improves the heat dissipation performance of high-power LED modules, enhances the current carrying capacity of the modules, and designs and develops ultraviolet LED light curing systems with kilowatt level or above.