Study On The Inorganic UV-Shied Finishing Of The Cotton Fabric

In the recent years, due to the increasingly use of solutions of fluorocarbons and freon, the ozonosphere of the atmosphere of the earth has been severely destroyed so that the amount of the UV that reaches the surface of the earth has been keeping increasing, which is more and more seriously affecting the health of the human beings. It is estimated by some experts that by the end of the 21^st century, the incidence of dermatosis will be the first one among all kinds of the diseases and will be the biggest enemy that threatens peoples' health. Cotton fabric, which is used to make clothes worn in summer, appeals to people for its characteristics of being hygroscopic, ventilative, anti-static, comfortable. As a matter of fact, its ability to resisting UV is relatively poor and is one kiang of the material that UV radiation can most easily go through. Therefore, we should waste no time in exploring some methods to make effective UV Shield finishing for the cotton fabric.Because the existing commonly used organic UV absorbents more or less have toxicity and irritant effect, they are limited to further popularization and application. Compared with them, nanometer new type inorganic UV shield agent not only has no side or toxic effect on people but also is a broad-spectrum shield agent which has higher chemical stability, heat stability and has a broader study-perspective. However, inorganic UV shield agent does not dissolve in water and to the natural fabrics like cotton lacks affinity, it is necessary theta before using it we should first change it into relatively stable rough-dispersoid: emulsion or suspended body, and then transfer the UV shield agent to the fabric by way of dip roll.In this thesis, I, through analyzing the anti-UV functioning mechanism of the nanometer power, select nanometer (Rutile)TiO2, ZnO as the UV shield agent. Given that water will be the finishing medium of the fabric, I, after heaving determined distilled water to be the dispersed phase, study the dispersing activity of the nanometer powder in the water. I use some methods such as the subsiding experiment, Zeta potential testing and so on to explore ultrasonic vibration and pH value's effects on nanometer-particle—water-dispersoid. According to the nanometer powder's dispersing mechanism and theory in the medium, I select the carbonxylate polyelectrolyte, which has the function of electrosteric stabilization, as the dispersant. On the basis of having studied the dispersant's effect on the surface electronic nature of the nanometer powder by way of Zeta potential, I primarily determine the dispersing art of anti-UV nanometer powder. I apply Laser Size Analyzer and SEM to explore the dispersing performance of the nanometer powder suspended liquid made under this art and obtain a fine dispersing effect In order to examine the anti-UV performance of the suspendedliquid of nanometer powder after having implemented simple dip-roll finishing to the cotton textile, I use UV Transmittance Analyzer to test the anti-UV ability of the textile. According to the UV transmittance curve, I can see that the protecting area of TiO2 and that of ZnO is slightly different; to make it more specific, TiO2's anti-UVB ability is better, while ZnO's anti-UVA ability is better. Given that the dispersants selected by this subject can make TiO2 and ZnO have relatively similar surface electric nature and the dispersants are o little difference, I try combiningly using TiO2 and ZnO so as to obtain better anti-UV effect in view of this, I use the transmittance of UVA and UVB as the index to make orthogonal experiments of the mixing rate of the nanometer powder, the dose of the dispersants and the pH value of the suspended liquid to determine the best combining formula which can make the cotton textile after finishing have the fine anti-UV effect both on the UVA and UVB area.The functional finishing fabrics should not only have the fine anti-UV performance but also should be washfast and have fine wearability. Thereof, this subject after having analyzed the performance of...