The Effects Of Machine Washing On Appearance And Tactile Comfort Of Worsted Woven Wool Fabrics

In this paper, sixteen thin worsted woven wool fabrics which were put into three categories (shrink-proof wool fabrics, wool-polyester blends and ordinary wool fabrics) were washed by washing machine according to national washing standards and home laundering. The appearance of flatness and size changes were measured after washing and the appearance of fabrics were given a quantitative research and analysis. The fabric prickle and handle were tested before and after washing and the differences between pre-washed. The fabric prickle and handle of the three different categories were compared and analyzed and the effects of different water temperature on appearance and tactile comfort of thin worsted woven wool fabrics were studied.Firstly, sixteen popular thin worsted woven wool fabrics which were classified as three categories were chosen to make the study. They were washed in reference to 8B program of GB/T 8629-2001 "Textile experimental family washing and drying procedures" and home laundering.Secondly, appearance of flatness of washed wool fabrics were evaluated according to AATCC appearance samples. It was found that smoothness appearance of shrink-proof wool fabrics and wool-polyester blends had reached more than 3.5 degree and ordinary wool fabrics were located between score 3 to 3.5. It meant that flatness of washed shrink-proof wool fabrics and wool-polyester blends were better than ordinary wool fabrics. And the results also showed that under the same other washing conditions, smoothness appearance of wool fabrics washed with the water temperature of 20℃were better than that of 40℃.By measuring the number and the diameter of the hairiness on the surface of the fabrics yarn, combined with subjective assessment of forearm experiments the effects of machine washing on prickle of worsted woven wool fabrics were studied. It was found that in the same washing conditions, the prickle results of shrink-proof fabrics were the largest, between 2.8-3.2, while prickle evaluation of the wool-polyester blends and ordinary worsted woven wool fabrics were close,between 2.4-2.8. There were significant impacts of washing process on prickle of thin worsted woven wool fabrics and prickle was markedly enhanced after washing. But there were no significant differences of prickle of fabrics washed in water temperature of 20℃and 40℃. By correlation analysis, it was found that the correlation coefficients between the hairiness proportion with 19μm diameter and the fabric prickle was the largest. Finally, handle properties of thin worsted woven wool fabrics both before and after washing were tested by KES-F. The results showed that in the same washing conditions, the bending rigidity and surface roughness of shrink-proof fabrics were the largest which meant that the biggest ability to resist deformation, the hardest feeling and the roughest surface. And the bending, shear and the surface roughness of ordinary wool fabrics were the smallest, indicating the most prone to deformation, the softest feeling and smoothest surface. Compared with pre-washed, the bending rigidity B, compression linearity LC, the friction coefficient of mean difference MMD, the surface roughness SMD, shear rigidity G and tensile linearity LT of the washed fabrics were significantly reduced. But the bending moment hysterics 2HB, compression reversibility RC, shear-lag moment 2HG and stretching RT before and after washing were no significant differences. Comparing the handle of fabrics washed in the two water temperature of 20℃and 40℃, there were no markedly differences which showed that the two water temperatures had no significant impacts on fabrics’handle.