UV printing requires that the printing equipment is installed with a matching UV curing device, when the substrate through the UV curing device, the UV light emitted by the UV lamp will be irradiated to the surface of the substrate, so as to achieve the purpose of curing UV ink (or UV varnish). So, how do you get good [UV curing] results? Please look below:
First, UV lamp surface temperature control
In general, the surface temperature of the UV lamp should be controlled at 200 ° C. If the surface temperature of the UV lamp is too high, it will shorten the service life of the UV lamp, make the UV lamp expand and deform, produce “self-fog” phenomenon, and even cause the reflective aluminum plate of the UV lamp shade to melt and deform. However, the surface temperature of the UV lamp should not be too low, when the surface temperature of some UV lamps is lower than 170 ° C, the ultraviolet radiation energy will decrease, resulting in the increase of the current of the UV lamp, and it is easy to burn the transformer or capacitor due to current overload over a long time. In order to prevent the occurrence of a series of adverse problems caused by the excessive surface temperature of the UV lamp, the following measures can be taken.
(1) The use of [UV-LED light source], which can emit high-purity monochromatic ultraviolet light with a wavelength of 365nm by converting light energy, which belongs to a cold light source. When the surface temperature of the UV lamp rises, the radiation energy of this light source can be highly concentrated in the ultraviolet light band that plays a curing role, and the curing effect is comparable to that of high-pressure mercury lamps.
(2) The reflector is installed so that the ultraviolet radiation energy emitted by the UV lamp is concentrated on the surface of the substrate, so as to make full use of it and achieve the purpose of reducing the surface temperature of the UV lamp.
(3) UV cooling device using air cooling and water cooling at the same time. First, by installing water jacket, water cooling method is used to maintain the appropriate working temperature of UV lamp; Secondly, the ambient temperature is cooled by air cooling to ensure the appropriate printing temperature and does not damage the surrounding parts. The air cooling method needs to use the air pump and the appropriate air system, and ensure that the fan power is consistent with the UV lamp power, and the exhaust air volume is generally calculated according to the following formula: exhaust air volume (m3/h) =150 (m3/h•kW) ×UV lamp power (kW). Whether the air cooling effect is effective needs to be judged by whether the exhaust pipe is damaged, air leakage, deformation or whether the tuyere has obstructions, etc., and the special exhaust pipe with high temperature resistance is used in actual production.
Second, the substrate surface temperature control
Even if the surface temperature of the UV lamp is kept within a reasonable range, the substrate of some materials will be embrittlement or deformation, and in serious cases, it will damage the surrounding parts and cause a fire.
Therefore, when the substrate is too thin or the temperature resistance is too low, it is first necessary to determine whether it can meet the requirements of UV printing production through a light solid test; For substrates that are not affected by temperature, UV radiation heat can be fully utilized to accelerate the curing speed. It can be seen that the surface temperature of the substrate is not the lower the better, but should be controlled within a reasonable range. Effective measures to reduce the substrate surface temperature are as follows.
(1) The use of optical plates to isolate the radiation energy of the UV lamp and the substrate, this method is usually used for UV printing of easily deformed substrates.
(2) Add a water cooling device at the cardboard holder. The common method is to improve the internal structure of the cardboard and inject cold water. On the one hand, this method can avoid overheating of the substrate surface, and on the other hand, it does not affect the coating temperature, and the use effect is good.
Auvcure is a professional manufacturer of all kinds of UVLED point light source, [UVLED line light source], UVLED surface light source and [UV curing machine], and can provide solutions and customization according to the actual needs of customers. The company has Japanese production technology, products are exported to South Korea, Japan, the United States, Brazil and other places. Welcome friends from all walks of life exchange guidance. If you want to know more about [UV light fixed machine] relevant information, welcome to online consultation customer service or call the company’s service hotline for consultation, we will be happy to provide you with quality service! Some of the information/pictures in this article are from the Internet, only for the purpose of sharing new information in the industry, not for commercial use. If any rights are involved, please inform us immediately, and we will delete it immediately. Thank you.
