Deodorization Of Cotton Socks By Sol-Gel Finishing And Its Characterization Approaches

Cotton socks are popular with customers for their natural properties and comfortableness. However, they are always in the muggy, anoxic and dump surroundings, where the bacterial metabolism is quickly reproduced and consumed long-chain fatty acids to give off a terrible smell. What are the specific compositions of socks' smell is still on the controversial. Moreover, there is no accepted characterization approach of deodorization effects in China.In this paper sol-gel is used to finish cotton socks. The finished socks can release negative oxygen ions by rubbing during the wearing. The negative oxygen ions can create an oxygen-rich condition in the shoes, which inhibiting the bacterial metabolism. In order to select the best process, the cotton socks are finished under different conditions of sol, pickup, curing temperature and time. The testing device of negative oxygen ions assembled by ourselves is used to test the samples' release amount of negative oxygen ions. The optimized conditions as follows:silica sol(n water:n KH-560= 20:1) 20 g/L, pickup 70%, predrying at 80℃for 20 min, curing at 120℃for 3 min. One pair cotton socks finished by this process can release more than 1000 ions/cm3 of negative oxygen ions. It can be seen in the photos of the germiculture in agar medium that the amount of bacteria in unfinished sock is larger than that of the finished one.GC-MS, HPLC, Halimeter, kitagawa precision gas detector tubes (ammonia and acetic acid type) are used to analysis the components of socks' smell. Testing results show that the amount of VSC in one pair of smelled socks is below 0.15 ppm, the amount of acetic acid is below 1 ppm, and the amount of ammonia is from 0.9 ppm to 10 ppm.Three characterization approaches of deodorization effects are built in this paper: gas detector tubes analysis, silver nitrate color change analysis and release amount of negative oxygen ions analysis. The results show that the gas detector tubes analysis and silver nitrate color change analysis can characterize the deodorization effects after the socks have been worn. But the gas detector tubes analysis must change the type of gas detector tubes for different target gas. And the silver nitrate color change analysis is suitable only for white socks. However, the release amount of negative oxygen ions analysis can characterize the deodorization effects of cotton socks without wearing. Compared to the traditional smell test, it is more objective and acceptable. Therefore, the release amount of negative oxygen ions analysis is the appropriate approach to characterize the deodorization effects of the sol-gel finished cotton socks.