UV absorber is one of many additives. One of its functions is to prevent ultraviolet rays from harming products. Ultraviolet absorbers are also used in various aspects by various manufacturers. Especially in summer, the ultraviolet rays in the air increase exponentially, which has a certain impact on our lives and items. We want to protect ourselves from the sun, so items and products naturally need protection. Otherwise, ultraviolet rays will cause damage to the molecular structure of the product, causing the product to accelerate fading, yellowing, and aging, seriously affecting the use of the product. At this time, ultraviolet absorbers are very important. . Although UV absorbers can solve the problem very well, there are many types on the market and the choices are multi-faceted. It does not mean that one UV absorber can be suitable for all products.
So, how to choose the right UV absorber for your product? ? First of all, you should have a basic understanding of UV absorbers.
Definition: UV absorbers are currently the most widely used type of light stabilizers. According to their structure, Divided into salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, triazines, etc. The most widely used compounds in industry are benzophenones and benzotriazoles. Quenchers are mainly metal complexes, such as divalent nickel complexes, etc., which are often used together with ultraviolet absorbers to have a synergistic effect.
Function:
UV absorber is a light stabilizer that can absorb sunlight and The ultraviolet part of the fluorescent light source does not change itself.
Since sunlight contains a large amount of ultraviolet light that is harmful to colored objects, its wavelength is approximately 290-460 nanometers. These harmful ultraviolet lights pass through chemical Redox reaction causes the color molecules of the product to eventually decompose and fade, causing the product to age.
Methods to prevent harmful ultraviolet light from damaging colors include physical Yes, there are also chemical ones.
Here we only briefly introduce the chemical method, that is: using ultraviolet absorption The agent effectively prevents or weakens the damage to the color of the protected object.
UV absorbers should meet the following conditions:
① Can strongly absorb ultraviolet rays (especially the wavelength of 290-nm )
②Thermal stability is good, even during processing Changes due to heat, low thermal volatility
③Good chemical stability and will not interact with the material components in the product Adverse reactions
④Good miscibility, can be evenly dispersed in the material, not Frost spray, no bleeding
⑤The absorber itself has good photochemical stability, does not decompose, and does not Color change
⑥Colorless, non-toxic, odorless
⑦Washing resistance
⑧Insoluble, or difficult to dissolve in water.
UV absorbers are used in plastics, coatings, dyes, and automobile windshields Glass, cosmetics, drugs, sunscreen, etc.
Generally speaking:
The application effect of triazine UV absorbers is significantly better than that of benzotriazole UV absorbers. In addition to excellent UV absorption properties, triazine light stabilizers also have other characteristics. Triazine UV absorbers can be widely used in polymers and have excellent thermal stability, making them have better processing stability. It has good chemical resistance and acid resistance, making it suitable for agricultural use. In practical applications, triazine UV absorbers and hindered amine light stabilizers have a good synergistic effect. When the two are used together, they have better effects than when they are used alone.
