The upgrading of photo-curing coating technology promotes the in-depth research and development of LED curing equipment

China Coatings Online News Information:
photo-curing coating technology upgrade to promote LED curing equipment research and development in-depth
to UV anti-fouling floor paint as an example, its reference formula as shown in Table 2. The light trigger 1173 is used in the formula, in conjunction with the medium pressure mercury lamp, can achieve a better curing effect, its effective UV utilization efficiency is 0.058, and the center wavelength of 380nm UV-LED and the light trigger effective UV utilization efficiency is only 0.014, only 1/4 of the medium pressure mercury lamp. If light trigger 819 is used, the effective UV utilization efficiency with UV-LED can reach 1.118, which is much greater than 0.226 with medium pressure mercury lamp. Therefore, the light trigger 819 and UV-LED match better.
Of course, the efficiency of light trigger in UV curing reaction will also affect the evaluation of overall efficiency, but the effective UV utilization efficiency is proposed, which provides a reference for the choice of UV light source and light trigger. The comparison between different light triggers requires more quantitative determination of the absorption spectrum of various light triggers, which needs further research.
4, high-efficiency high-power UV LED photo-curing system
In order to meet the lighting needs of high-power UV light sources in optical curing industry applications, we have researched and developed a high-power UV LED photo-curing system above the kilowatt level in view of the difficulties of existing high-power LED packaging technology. The LED curing system uses a sandwich package structure of copper plate and aluminum nitride plate, which is connected directly to the copper plate as an electrode, and AlN board as an insulated thermal guide plate, which achieves a high power density package structure.
photo-curing coating technology upgrade to promote LED curing equipment research and development in-depth
Figure 3 floor coating LED UV curing system and its light source module
using copper plate electrodes instead of thin film circuit board connection, can increase the current load capacity of LED module by more than 10 times, solve the problem of limited flow of printed circuit board film, increase the drive current of LED module, the package power per unit area to 20 to 500W/cm2. In the high-power integrated package, it provides more choices for the series and concatenated combination of LED chips, and can design parameters such as voltage and current of luminaires more reasonably, reducing the design requirements for driving power supplies.
AlN board as an insulation layer between the positive and negative electrodes of the copper plate, the electrode of the copper plate and the radiator, can not only achieve good insulation effect, but also ensure the efficient export of chip heat, thereby improving the thermal properties of the LED module. Moreover, alN plate surface does not need to be coated with metal film, the production process is simple, can effectively improve the yield of finished products, reduce manufacturing costs.
addition, the LED module package uses homemade, high-efficiency thermal conductive adhesive as a bonding material. The thermal conductivity of the thermal conduction glue can reach more than 120W/(m.K), which ensures thermal conduction between the chip and substrate, copper plate and AlN board, reduces the internal thermal resistance of the package structure, and further optimizes the thermal performance of the LED module.
3 is a self-developed floor coating LED UV curing system and light source module photos. The input power density of this mobile UV curing system reaches 200W/cm2, the total power is 14kW, the structure is small, the operation is convenient, the construction is simple, can be well applied to a variety of different floor curing treatment.
5, conclusion
UV curing as an efficient and environmentally friendly green technology, in recent years has been rapidly developed and popularized. Especially with the growth of China's economy, UV curing applications have great market potential. In this trend, it is urgent to develop high-power UV LED photo-curing system to meet the needs of applications. In view of the technical difficulties existing in the high-power LED module package, a sandwich package structure using copper plate and AlN board has been invented, which effectively improves the thermal performance of the high-power LED module, improves the load-carrying capacity of the module, and designs and develops a UV LED photo-curing system above the kilowatt level.