UV radiation – Increased protection
As you know, ultraviolet radiation comes from the Sun. It is just one of the many electromagnetic rays emitted by the Sun. The range of ultraviolet radiation is from 400 to 100 nm and was determined by the International Commission on Illumination (CIE), which specified three types of UV radiation: UV A, UV B, UV C. UV A radiation is absorbed by oxygen in the atmosphere layers located at an altitude of over 96 kilometers. UV B radiation is absorbed by the stratospheric ozone layer as well as water vapor and carbon dioxide. Only UV C radiation reaches the Earth’s surface.
Degradation of threads under the influence of UV radiation
by absorbing energy leads to:
- lowering thread strength
- reducing the resistance of the thread to friction
- loss of thread colors
GRAFF garments with increased resistance to solar radiation use appropriate coloring substances that behave like photocatalysts to minimize the effects of fading of the fabric or loss of it’s strength.
While testing the resistance of the fabric to UV radiation, the following points were taken into consideration:
- intensity of radiation
- exposure time