Textiles are suitable microbial growth environments which causes disease transmission, stink, colorful spots and fabric strength reduction. So, a lot of orts have been made to increase the resistivity of textiles against the rapid growth of microorganisms such as bacteria. This research focuses on the antimicrobial of cotton fabrics using colloidal aqueous of nano particles of silver. Initially, in dry-pad method, the concentration of silver nano particles must be measured for antimicrobial of textile against 3 bacteria of Staphylococcus aureus, Esherichia coli and Pseudomonas aeruginosa. Different conditions of stirring illustrates that using ultrasonic and mechanical agitator gives better results in antimicrobial properties of samples. Due to the difficulties of adding a new route to the finishing process of cotton textiles, efforts have been made to combine the dry-pad and antimicrobial route with the common finishing and printing. For this purpose two materials of Fixapret ECO as a crosslinker and Cellofix ME as a component of resin have been used in anti wrinkle finishing. The waterproof material was fluorocarbon type. In printing route, silver nano particles must be added to printing paste or must be applied on textile by the use of binder. The properties of textile have been investigated by measuring the resistivity of sample against bacteria, mechanical strength, abrasion and washing stability. The results showed that treated samples by dry-pad method has the best resistivity against bacteria and temperature increase will cause enhancement in resistivity. In this method, due to the lack of a retentivity of material to maintain the silver nano particles, the abrasion and washing stability will reduce which will increase by temperature increment. The antimicrobial properties will increase by the use of anti wrinkle materials, due to the release of formaldehyde and it will enhance with the increment in the concentration of this material. The resistivity against bacteria in this method is less than that of dry-pad method. Due to the physical restraint of silver nano particles in textile, after abrasion and washing treatment, decrease in antimicrobial properties was seen. In printing method, the fabric surface is coated with binder which will reduce the contact of bacteria with silver nano particles, so, the antimicrobial properties was reduced. .
