# Effect of Hybrid Knitted Structure on Clothing Pressure
## 3 Results and Discussion  
### Tensile Properties  
Figure 3 shows the force-strain diagrams acquired from the inlay yarn and base knitted fabrics in warp direction. As depicted in the diagram, these fabric structures exhibited a varied range of elastic properties. Single pique exhibited the lowest strain as the force approached 100 N which was the maximum force in our study. However, according to the findings from other studies, this might not always be true when different yarn types were involved [12,27,28]. In our study, single jersey was stretchier than single pique and displayed a moderate level of strain at 100 N among all fabrics. The mock rib structures showed the highest levels of strain, with the 2 \(\times\) 2 mock rib demonstrating a greater strain level than the 1 \(\times\) 1 mock rib at 100 N. This is because of the accordion-like rib structure formed by the successive stitches in the weft direction. The increased alternating width of the columns in the face and back loops of the 2 \(\times\) 2 mock rib enhances the fabric's stretchability without adding spandex [29, 30, 31, 32]. The commercial sleeve made from a warp-knitted fabric exhibited the highest degree of stretch among the fabrics at 100 N, which can be ascribed to its warp-knitted structure and higher proportion of spandex used in its construction [33]. The results showed that the force-strain curve for the inlay yarn did not reach 100 N due to its exceptionally high stretch, which might have hit the max displacement range for the instrument. Figure 4 illustrates the comparison of elastic properties before and after inserting inlays in weft and warp directions. The inlays were not applied to the commercial sleeve because it was a warp knit unlike other experimental sleeves, and it served as a reference for our prototypes. There were noticeable changes in elastic properties of fabrics after inlay insertion. Single jersey structure showed contrasting behavior to other fabrics in force-strain curves, where the strain decreased as the force approached 100 N, after inlay yarn insertion in weft and warp directions (Figure 4a,b). The single pique structure showed an increase in strain at 100 N, after the inlay yarn was inserted, in both weft and warp directions. The mock rib structures exhibited increased strain at 100 N in the weft direction after inlay yarn insertion (Figure 4e,g), while in the warp direction, the total strain level at 100 N remained the same (Figure 4f,h). Figure 3: Force–strain diagram of fabric structures, single pique, single jersey, 1 \(\times\) 1 mock rib, 2 \(\times\) 2 mock rib, fabric of commercial sleeve in warp direction and inlaid yarn. Adding inlay yarn produced a stretchier fabric at 100 N in the weft and warp direction for single pique, and specifically in weft direction for mock rib structures. Based on the elastic properties results from our study and previous research, inlay yarn insertion has a greater impact on elastic properties in the weft direction than in the warp direction [3]. For further analysis, we measured the stretch modulus up to a strain level of 50% that is reported as a critical strain range in elbow bending which aligns with the range of skin stretch [34]. Figure 5a,b demonstrate that inlay yarn insertion improved fabric stability in the weft direction by increasing the stretch modulus across all weft-knitted fabrics which are displayed in front of each diagram.