What is the use of studing textile technology? is there any job opportunity for it?

Sure, its the study of fabrics used for clothing, sails, pool covers, fabric shades, umbrellas etc etc. It has an enormous job potential if thats what you are intersted in. Nylon and Kevlar are two mainstream fabric materials that have come out of the industry in the last 50 years. Lately, lighter, stronger wicking sythetic fabrics have been developed for sports, and the newest one that is still trying to gain foothold is a fabric with silver woven in to destroy smells and bactieria that cause it. To me it would be a cool industry. Probably alot of chemestry involved.