Optimized UV protecting coatings by combination of organic and inorganic UV absorbers

Abstract The ultraviolet (UV) protection of organic and biological materials against photodestruction is of high practical interest. Since protective coatings containing individual organic or inorganic UV absorbers contain absorption bands in different wavelengths regions below 400 nm, a combination of both types of absorbers can improve the UV protection functionality. Nowadays, the recent sol–gel technique enables the preparation of coatings from inorganic UV absorbers like TiO 2 combined with embedded organic UV absorbers. The absorption behavior of these hybrid coatings on glass was investigated as function of layer thickness and concentration for two different organic UV absorbers (based on benztriazol and phenylacrylate). The optimization of the coating composition is supported by model calculations of the transmission spectra and allows the preparation of coatings with nearly perfect light absorption at λ

[1]  David Stroud,et al.  The effective medium approximations : Some recent developments , 1998 .

[2]  B. Mahltig,et al.  Modified Silica Sol Coatings for Water-Repellent Textiles , 2003 .

[3]  D. Kundu,et al.  UV absorbing transparent sol-gel derived coatings on glass , 2003 .

[4]  M. E. D. Zaniquelli,et al.  Aluminium-doped zinc oxide films prepared by an inorganic sol–gel route , 2004 .

[5]  O. S. Heavens,et al.  Optical Properties of Thin Solid Films , 2011 .

[6]  Xiao Hu,et al.  Influence of titanium content and temperature on optical and mechanical properties of sol–gel derived TiO2/γ-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane hybrid organic–inorganic films , 2003 .

[7]  C. Trapalis,et al.  Optical properties of SiO2-TiO2 sol-gel thin films , 2004 .

[8]  C. Brinker,et al.  Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing , 1990 .

[9]  H. Inoue,et al.  Optical properties of quinizarin doped SiO2–TiO2 gel , 1999 .

[10]  I. Eleftheriadis,et al.  UV-absorbers in the dyeing of polyester with disperse dyes , 2004 .

[11]  Helmut Luther,et al.  New UV Absorbers for Cosmetic Sunscreens – A Breakthrough for the Photoprotection of Human Skin , 2004 .

[12]  C. Rottman,et al.  Advanced Sunscreens: UV Absorbers Encapsulated in Sol-Gel Glass Microcapsules , 2003 .

[13]  J. Xin,et al.  Low Temperature Sol-Gel Processed Photocatalytic Titania Coating , 2004 .

[14]  A. Djurišić,et al.  Modeling the optical constants of organic thin films: application to 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) , 2000 .

[15]  T. Fritz,et al.  Correct interpretation of spectral interference measurements of weakly absorbing films of micrometer thickness. , 2004, Optics letters.

[16]  T. Fritz,et al.  Precise determination of the complex optical constant of mica. , 2004, Applied optics.

[17]  Noh,et al.  Self-consistency conditions for the effective-medium approximation in composite materials. , 1991, Physical review. B, Condensed matter.

[18]  Hyunmi Lee,et al.  UV absorber aftertreatment to improve lightfastness of natural dyes on protein fibres , 2001 .

[19]  B. Mahltig,et al.  Light Fading and Wash Fastness of Dyed Nanosol-Coated Textiles , 2004 .