A Printable Ultraviolet Radiation Dosimeter

Abstract

The present invention relates to a device formed by printing a substance that is sensitive to exposure to ultraviolet radiation on any substrate, which acts as functional ink and then as a dosimeter for ultraviolet radiation (UV-A, UV-B or UV-C). A conventional printer is used for printing, but with the UV-radiation-sensitive substance instead of ink, on paper, adhesive labels, polymer, fabric, or other substrate which can immobilize the active substance used. After being printed with the active substance, the substrate, cut into a specific shape, is then used as a UV dosimeter, for personal or environmental monitoring, if the substance used as ink is luminescent and the intensity of the emitted luminescence decreases appropriately according to the UV-radiation dose received, such as the lanthanide complexes, or other substance that results in a compound that is sensitive to UV radiation, or any type of luminescent substance which changes with UV radiation, and is dispersed in a solvent enabling it to be used as an ink substitute in the printer, or pure, or also when the ink changes colour according to the UV-radiation dose received. The printed substrate may have a specified area that is protected from radiation exposure to be used as reference to evaluate the dose of UV radiation. In the case of a luminescent substance, the accumulated dose may be read by placing the substrate, following exposure, into a reader which measures luminescence intensity at a wavelength range corresponding to the characteristic emission of the substance used. The accumulated dose may be measured by comparing luminescence from the exposed portion of the substrate to that of the non-exposed portion. The relative measurement can be converted into dose. In the case of a substance which changes colour according to the UV-radiation dose received, the reading can be visual, qualitative by comparing the colour of the exposed area to the non-exposed area, or quantitative by placing the substrate into a reflectance or absorption reader for the corresponding spectral region, following calibration using values which correspond to each accumulated-dose range. Besides allowing the received and accumulated radiation dose to be determined, the same system may, optionally, enable visual monitoring for detecting a permitted UV-radiation-dose limit, for use in controlling industrial processes or preventing individual overexposure.