The high percentage of disulfide crosslinkings in the exocytic layer, fatty acids and the presence of scales on the surface of wool fibers, weakens the dimensional stability of the fabric and problems such as felt and shrinkage, and therefore this is a serious problem for the garment industry. Conventional methods of modifying the wool surface to prepare it for the next steps, such as dyeing, mainly use materials that are polluting the environment. There are also many wet finishings in the wool industry that require a large amount of water and chemicals and then drying processes. In addition, these finishings are uneven and cause serious damage to the fabric. Therefore, the use of dry surface modification methods that prevent pollutants from entering the environment is being considered today. In this regard, in recent years, plasma and ozone methods have been used to improve the surface of fibers in woolen fabrics. In this project, for the first time, an attempt has been made to use a combination of plasma and ozonation operations to modify the surface of the wool fabric, which in addition to high efficiency, minimizes physical and chemical damage to the wool. Hence, three main phases were proposed in this project. In the first phase, the optimal conditions for ozone operation and in the second phase, the optimal conditions for plasma operation were investigated to obtain the best possible surface modification. In the final phase, the plasma and ozone operations were combined under the optimal conditions. The effect of plasma, ozone, and plasma-ozone operations on the surface modification of woolen fabric was studied by eva‎luating the parameters of whitish-yellow index, dehydration, felt shrinkage, strength, SEM images and dyeing behavior with three uniform dye acids, milling and supermilling. The results of the first phase show that the plasma operation in 2.5 minutes, in addition to increasing the strength, creates a favorable shrinkage. In the second phase, it was found that with 15 minutes of ozone treatment on the wool sample, shrinkage decreased and whiteness increased. After modifying the surface of the woolen fabric with 2.5 minutes of plasma operation and 15 minutes of ozone operation, it was observed that because the operation was limited to the surface, the percentage of strength reduction is acceptable. On the other hand, by removing the lipid layer on the surface of wool fibers using this operation, in addition to improving wettability, a significant reduction in the percentage of wool felt shrinkage was observed. Finally, it can be concluded that it is possible to replace this combined method with chemical methods to perform continuous operations with reduced time and energy. The results of plasma-ozone-treated wool dyeing behavior showed that its dyeing speed in dyeing with uniform acid dye, milling, and supermilling has increased compared to the control sample, which can be related to the oxidation and cleavage of disulfide bonds in dye penetration caused by this operation. On the other hand, the results of the study of changes in color absorption of plasma-ozone-treated samples indicate that this operation did not affect the color absorption of wool samples. Similar results were observed in reducing the dyeing temperature of this sample with milling and supermilling dyes. In general, no change in abrasion fastness, wash fastness and optical fastness of wool was observed by plasma-ozone operation.

اكبر خدامي. هاله خليلي

محمدعلي الشريف

فرزانه علي حسيني. حسين ايزدان