UV Printer Light Source System

It consists of a UV lamp tube, lampshade, transformer (ballast), and capacitor (trigger).
1. Currently, there are two types of UV lamps on the market: high-pressure mercury lamps and metal halide lamps. Domestic equipment generally uses high-pressure mercury lamps, while some imported equipment uses metal halide lamps.
1. Selection of UV lamp power.
(1) The power of a UV lamp is the radiation energy of the UV lamp, also known as penetration. Firstly, it must meet the requirements for the spectral wavelength and power density of UV ink (varnish) absorption. If the power of the UV lamp is insufficient, even if the lighting time is longer and the number of times it passes through the UV curing device is more, the product cannot achieve complete curing. On the contrary, it can also cause the surface of UV ink (varnish) to age, seal, become brittle, and at the same time, the adhesion of ink (varnish) is also poor, which will result in poor interlayer adhesion of overprinting. Because low-power UV light cannot penetrate the bottom of the ink layer, the bottom is not cured or not fully cured.
(2) The power of UV lamps generally needs to meet the requirement of 80-120W/cm, but the higher the power, the greater the heat. Therefore, the power should be selected based on the different curing materials and curing speed.
(3) The maximum lifespan of UV lamps is generally 800-1000 hours, and they should be replaced immediately after reaching it, as the intensity of the ultraviolet light emitted by UV lamps during this period weakens, which can affect the curing effect. At the same time, it is recommended to clean the surface of the lamp tube and the reflector plate on the surface of the reflector with anhydrous ethanol at an appropriate time during the use period, depending on the production environment (dust content in the air), and then turn the UV lamp tube 90 °. This is beneficial for all UV rays to effectively radiate onto UV ink or varnish, ensuring a certain degree of penetration.
2. The types of reflective covers include focused, non focused, and multi sided reflective. Generally, the focus type is used. The structural feature of this reflector is that the reflected UV light energy is concentrated, and the efficiency of photocuring is high, which is conducive to the solidification of thick ink layers and can completely solidify the deep layers of ink. In this regard, attention should be paid to the material selection and shape of the reflector.
(1) The selection of materials must be made of aluminum, rather than iron or stainless steel to save costs, as stainless steel plates will turn black at high temperatures. After turning black, they will not only not reflect light but also absorb light. The best reflective effect is the mirror aluminum oxide plate, which can have a reflectivity of over 80%, greatly improving the utilization rate of ultraviolet radiation.
(2) The shape of the shape reflector is to ensure that UV light can be gathered together, so the shape of a semicircle arc is the best choice. Also pay attention to the installation position of the UV lamp tube to ensure it is at the focal point. In addition, the reflective cover is an important channel for UV lamp heat dissipation, so the outer side of the aluminum cover should be processed into a heat sink to increase the heat dissipation area. The reflector plays a very important role in UV curing devices. Some manufacturers often overlook its role and use alternative products to serve as reflective covers, or even do not install reflective covers, resulting in 40% -50% of UV lamp energy being wasted in vain. And some manufacturers' response is to blindly increase the power of UV lamps, which not only fails to fundamentally solve the problem, but also causes greater energy waste.
3. The selection of transformer must match the power of the UV lamp. That is, the transformer must have sufficient output voltage to ensure that the UV lamp can work at full power. If the output voltage is too high, it will cause the lamp tube to burn out; The output voltage is too low, and the lamp cannot operate at full power, resulting in insufficient UV output intensity.
4. The selection of capacitor capacitance should be matched with the lamp tube and transformer. Select the withstand voltage level of the capacitor used based on the output voltage of the transformer. If selected improperly, it will cause capacitor breakdown and affect the normal operation of the UV curing device.