What is UV Absorber?

UV Absorbers are used in coatings to protect surfaces and reduce the harmful effects of the sun. The addition of these products to surfaces increases the resistance to ultraviolet radiation and preserves the color brightness of the surface, extending the life of the polymer and therefore the end products. UV Absorbers should not be confused with blockers. In addition, instead of blocking the light, they sacrifice themselves to preserve the polymers on the surface they protect.

This is why they are used to combat UV rays coming to the surface from the sun. Because these additives have a tendency to attract UV rays. They prevent UV rays from reaching the substrate of the coatings. At this point, UV Absorbers do not allow sunlight to reach the polymer and instead protect the coating by absorbing UV rays.

Since the energy emitted by UV rays does not disappear, the rays absorbed by UV Absorbers have to go somewhere. Therefore, UV Absorbers convert the energy from UV rays into heat and radiate the absorbed heat. In this way, UV Absorbers safely release UV rays without damaging the material they are protecting.

The amount of product needed depends on the concentration of the UV absorber and the thickness of the surface. The relationship between UV Absorber concentration and surface thickness is not linear. More than the required amount reduces the effectiveness of the material. Thicker materials may need higher concentrations than anticipated. Formulators need to do extensive testing to find the concentration that should prevent photodegradation.

These tests are important to find the right UV Absorber. Not all products absorb the full UV wavelength spectrum. These products are not transparent. This is usually because they absorb UV rays, not light. UV Absorbers at a wavelength of 400nm block blue light waves. This is to avoid making the underlying material appear yellow.

Although wear is very slow, UV absorbers will wear out over time while other forms of UV protection will renew themselves. To avoid problems with UV damage to the material, reapplication of the coating with UV Absorbers should be done periodically or another form of protection should be sought. Alternatively, UV Absorbers can be used for short-term solutions such as disposable products or products that are only regularly exposed to the sun.

What is a UV Absorber used for?

UV Absorbers are added to formulations because ultraviolet rays damage the chemical bonding structures of polymeric materials. Any surface exposed to the sun's ultraviolet light for long periods of time is seriously damaged. UV Absorber materials are critical to produce products that can perform well even when exposed to UV rays for long periods of time. The use of these additives offers many benefits for products that need to stand in the sun and maintain their integrity at the same time.

These UV Absorbers work by absorbing high energy UV rays and releasing them at a lower energy level which is less harmful to the polymer. To combat the destructive effect of UV rays, in the early days of long-term outdoor applications, either polymers with intrinsic resistance to degradation or auxiliary additives such as carbon black or titanium dioxide, which are preferably used to absorb or reflect UV rays, should be chosen.

What are the Types of UV Absorbers?

• Benzotriazoles
• Benzophenones
• Hydroxybenzoates