UV Technology

Introduction

In the process of UV drying , ultraviolet light interacts with chemical specifically designed to dry ink and paint more quickly and cheaply than conventional drying systems. UV technology has been developed over 30 years ago especially for the printing industry and the wood industry, but today is also used in various areas such as the automotive industry.

Ultraviolet light

Ultraviolet radiation (so-called UV or ultraviolet rays or ultraviolet light) is an electromagnetic radiation, belonging to the electromagnetic spectrum, which emits a shorter wavelength than that of visible light but longer than X-rays. The name means “beyond violet” (from Latin ultra, “beyond”) because the spectrum consists of electromagnetic waves with higher frequencies than those that humans identify as the colour violet, being the one with the shortest wavelength.

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Ultraviolet light can be divided into two ranges: near UV spectral range (380-200 nm) and far-UV spectral range (200-10 nm). When considering the effect of UV radiation on human health, the range of UV wavelengths is typically divided UV-A (400-315 nm), UV-B (315-280 nm) and UV-C (280-100 nm). The Sun emits ultraviolet light at all three bands UV-A, UV-B and UV-C but, due to the absorption by the first Ozone layer of the atmosphere, about 99% of ultraviolet rays that reach the earth’s surface is UV-A. Almost 100% of the UV-C rays and 95% of UV-B rays is filtered by Earth’s atmosphere.

For further information about traditional UV lamps visit the related product page:

UV lamps

The benefits of UV-based products (paints and inks)

The advantages of using inks/UV based paints are numerous, among which we can highlight:

  • Stain and water saving products: paints/water-based inks contain 60 to 70% of the total volume of water (which is then to be lost to evaporation in the drying process.), while the UV-based products can be used to 100% since the process of drying  does not occur by evaporation but by polymerization (change of state similar to crystallization), then you save water and increase the efficiency of use of the dye.
  • Reduce environmental impact: paint/water-based inks generally contain about 5%  of VOC (volatile organic compounds) that are released into the environment when printing or during maintenance/cleaning of the machines. Those do not contain UV-based, so using them helps to reduce the environmental impact.
  • Saving energy consumption: based on the applications, the use of paints/UV inks can result in savings of energy by 75% compared to the one used to dry a surface treated with the same paint/water-based ink.

The UV curing process

The UV drying process requires first of all a light source that directs its light on a painted surface; the layer of color (paint or ink that is) is composed of a product called photo-initiator, which has the fundamental task of absorbing UV energy from the light and trigger a chemical reaction, that within a few fractions of a second, converts the layer from liquid to solid.  The composition of this particular product is made up of monomers and oligomers: the first are low molecular weight materials and have the task of creating physical links due to the curing of the paint (or ink) during exposure to UV rays; the monomers also act as diluent in some products which are generally used to correct the viscosity of the product which lies on the surface, so they are also called reactive diluents. In contrast, oligomers tend to have a very high molecular weight, and are generally responsible for determining the degree of finish of the painted surface, such as flexibility, subtlety, etc.

UV QBe and environment

Environmental sustainability. Energy efficiency. Ecology. SPM has the ideas and technologies to transform words into deeds. Here’s how the SPM products contribute to reduce environmental impact:

  • Dimension and weight: our products are designed and improved over time to try to minimize the overall weight and size, to ensure an affordable, easy to transport and install, less weight means less fuel consumption for transport.
  • Function Stand-by Up to 10%: we have optimized our electronic control to ensure stability of the lamp signal at low power, in order to save energy when not in use and be more responsive to restart.
  • Continuously adjustable power: thanks to the closed loop control, we were able to make extremely fine adjustment of power, in order to optimize the power just as the user wants to calibrate.
  • Increased lamp life due to the command square wave: was chosen this type of signal because, the various tests performed in our laboratory, revealed that this waveform was the most efficient way to control incandescent lamp UV, so we optimized our electronic in order to obtain a stable result, which is translated into longer life of the lamps, greater energy and continuity of work.

For further information about UV QBe electronic power supply visit the related page:

UV QBe electronic power supply

Advantages of ROI and energy savings

Below are shown schematically the main benefits, grouped into three categories,resulting from the use of a QBe power supply series. For more information please contact us using the contact details in the relevant section.

UV Radiation

There are no “dark periods”: higher yield of the lamp  at the same power supplied, compared to a conventional power supply or greater saving due to less frequent lamp changes.

UV drying system:

  • Compact size: allows easy installation and also saves space in the cabinet.
  • Flexibility of use: suitable for lamps of different size.
  • Also available with water cooling: cooling systems adaptable to existing lamps (industrial graphics industry).
  • Easy wiring: over three-phase power, are only three control signals and the lamp outuput.
  • Security: protection against short circuits integrated.
  • Integrated Modbus module: ability to control the power supply modules without additional PLC
  • Adaptive input voltage: 400 to 480 V power supply, ensuring a constant light output. If necessary, plug in DC.
  • Reactivity: faster response for monitoring the current supplied to the lamp.
  • Closed loop control:built-in sensors for monitoring the current supplied to the lamp.

Energy saving:

  • Reducing power dispersed: at the same power supplied to the lamp, savings in power consumption.
  • Cos φ costant: this parameter is almost equal to 1 then it means that almost all of the required power to the network ends up on the lamp, reducing energy waste
  • Stand-by function:the device is able to reduce power by up to 10% in times of no work, it saves energy when not needed, helping to reduce the environmental impact.