Azabenzotriazol containing ultraviolet absorber and preparation method thereof

Abstract

The invention discloses an azabenzotriazol containing ultraviolet absorber the molecular structure of which comprises both a benzotriazole structure and an azacycle structure. Particularly, the invention also discloses the preparation method of the absorber, which comprises the following steps in sequence: 1) carrying out a diazotization reaction on o-nitroaniline derivatives and getting a diazotization solution; 2) carrying out coupling reaction on diazonium salt of the o-nitroaniline derivatives and derivatives of pyrazolone or pyridone and getting a coupling product; and 3) carrying out reduction reaction on the coupling product to finally obtain the azabenzotriazol containing ultraviolet absorber. The molar extinction coefficient of the ultraviolet absorber disclosed by the invention is evidently lower than that of other azabenzotriazol containing ultraviolet absorber with a similar structure.

Description

technical field The invention relates to a nitrogen-containing heterocyclic benzotriazole type ultraviolet absorber and a preparation method thereof. Background technique Ultraviolet (UV) rays, invisible rays located in the high-energy region of sunlight, are one of the main "organism killers". The long-wave ultraviolet UV-A (315-400nm) and medium-wave ultraviolet UV-B (280-315nm) in sunlight can penetrate the atmosphere and affect the ecological environment of the earth. Its harmfulness lies in that long-term irradiation of ultraviolet rays on organic substrates can cause photochemical reactions, change the chemical structure of the substrate and affect its performance. For example, ultraviolet rays can damage proteins and DNA, and induce human eye and skin lesions; ultraviolet rays can cause photooxidative degradation of polymer materials and damage material properties; ultraviolet rays can also cause photofading of dyes (pigments) and change their color. Considering the...

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Problems solved by technology

However, the existing benzotriazole ultraviolet absorbers specifically belong to the benzene ring type benzotriazole ultraviolet absorber, and when this type of absorber is applied in the field of textile protection, there is still the defect that the ultraviolet protection ability is relatively weak and the dosage is too large How to develop UV absorbers with stronger UV absorption capacity has always been one of the urgent problems in the field of photoprotection.

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