The Preparation Of SiO₂ Colloidal Microspheres And Its Application Of Structural Coloration On Textile By Self-assembly

Different from the traditional textile coloring technology, without dyes and pigments,structural colors produce the color by the selective reflection of light through dispersion,scattering, interference and diffraction, which have the characteristics of high brightness, high saturation, permanent color and iridescent effect etc. As a kind of typical bionic coloration ways,photonic crystals attract attention by domestic and foreign scholars in dyeing and finishing industry. In the work, we were focus on the fabrication of three-dimensional SiO₂ photonic crystals on textile fabric by self-assembly with colloidal spheres, the beautiful structural colors with vivid effect were obtained by controlling the self-assembly factors and the textile substrates,which provide theoretical support and practical experience on the fabrication of photonic crystal structural colors on textile fabrics.The major work could be summarized as the following four aspects: 1. The monodispersed SiO₂ microspheres were prepared by St?ber method, and the influences of TEOS, NH3 and H2 O concentrations on the effects of the diameter and monodispersity of SiO₂ microspheres were studied by the laser particle analyzer, TEM and FESEM; 2. The gravitational sedimentation and vertical deposition method were used to construct SiO₂ photonic crystals on textile fabrics, and the self-assembly factors（like relative humidity, assembly temperature, concentration of microspheres, assembly solvents） on the effects of SiO₂ photonic crystal structures and the structural colors were investigated; 3. With the different specifications of polyester and silk fabrics as the substrates, the influences of fabric structures on the effects of self-assembly were investigated; 4. With the chitosan quaternary ammonium salt as the finishing agent to treat the fabrics after self-assembly, the method to improve the fastness of Si O₂ photonic crystal on textiles was developed.The result shows that: 1. The St?ber method were used to prepare the monodispersed SiO₂ microspheres in the diameter of 180-380 nm through controlling the concentrations of TEOS,NH3 and H2 O. The size of SiO₂ microspheres increase with the increasing of TEOS, NH3 and H2 O concentrations; 2. During the self-assembly, the high quality face-centered cubic（FCC）arrayed SiO₂ photonic crystals were constructed on the polyester and silk fabrics at the temperature of 25 ℃, RH at 60%, the mass fraction at 1.5% and 2.0%., respectively. During the gravitational sedimentation self-assembly, SiO₂ microspheres were self-assembled on the surfaceof fabric surface by gravity force and obtained one-sided structural colors. While, during the vertical deposition self-assembly, SiO₂ microspheres were self-assembled on the surface of fabric surface from top to down by capillary force, and obtained two-sided structural colors; 3. It is thought that the fabrics with smooth and flat surface, ordered and dense yarn construction are more suitable used as substrates. Compared with silk fabrics, on the premise of the same or similar structure, polyester fabrics are advantageous to fabricate regular photonic crystals due to the hydrophobicity and stiffness; 4. The SiO₂ photonic crystals on the textile substrates could display brilliant structural colors, and with the increase of viewing angles and the diameters of colloidal microspheres, the structural colors blue shift, otherwise, turn to red shift. The color fastness of SiO₂ photonic crystal structural colors were improved after the treatment with chitosan quaternary ammonium salt solution.