Dimensional change
The dimensional change of knitted specimens was shown in Fig. 3. ‘PF’ was reduced by 34 % in course-wise and 6 % in wale-wise compared to ‘P’. The wales of ‘PF’ are drawn closer together by floats because the loop of miss stitches tends to display faint horizontal lines; consequently, course-wise reducing occurred. The high stretch of material added to reducing along with the structural and characteristics of material both led to reducing in wale-wise. ‘PT’ was observed 25 % increasing in course-wise and 28 % reducing in wale-wise. Spencer (2001) mentioned that tuck loops reduce fabric length because the higher yarn tension and held loops pull on yarn from adjacent loops. Course-wise increasing occurred because tuck loops also pull the held loops downwards and spread outwards; consequently, the dimensional change of ‘PT’ in this study and Spencer’s description about tuck stitch coincides. The dimensional change in ‘PFT’ showed an 11 % increase course-wise and 30 % reduction wale-wise. The combing of knit structure provides greater fabric stability both wale-wise and course-wise.
Figures 4 and 5 show knit specimen changes in weight and thickness. The heavier weight of knit specimen was, the thicker its thickness was in descending order ‘PF’, ‘PFT’, ‘PT’, ‘P’. Thickness and weight of specimen were influenced by density change caused by reducing and increasing fabric size. Thus, high density caused by floating in course-wise causes more knitted fabric weight gain than by loop overlapping.
Stretch properties
Figure 6 indicated that the stretch value decreased in all structure and direction except wale-wise of ‘PF’ compared to ‘P’. Course-wise, ‘PF’ showed a sharp decrease (67 %) while ‘PT’ showed a 7 % relatively small decrease. It seems that the material effect by stretch properties added to the reducing cause by yarn floating in ‘PF’. Stretch properties of yarn restricted increasing in ‘PT’. Wale-wise indicated a 29 % ‘PF’ increase versus a 32 % ‘PT’ decrease to show that the tuck stitch structure which held the loops reduced the stretch value. There was a value decrease 34 % in course-wise and 24 % in wale-wise each for ‘PFT’. The stretch value in course-wise is influenced by yarn floating rather than loop overlapping while stretch value in wale-wise is caused by loop overlapping versus yarn floating.
There was no significant value change on knit structure and direction in elastic recovery (Fig. 7a, b). The recovery value gap among knitted specimens was lower at 1 h than at 60 s. The stitch loops bent and restricted by the external force loop of stitch take on a form of stability and shape retention in over time.
Correlation with clothing pressure, fabric size and stretch properties
Figure 8 shows the clothing pressure on each specimen knit structure. The clothing pressure value of ‘PF’ was higher 60 % than that of ‘P’; however, the clothing pressure value of ‘PT’ was higher 9 % than ‘P’. The degree of clothing pressure vertically exerted on the body depends on course-wise dimensional changes of knitted fabrics. The result measure value of clothing pressure of ‘PFT’ was 21.96 mmHg which is higher 37 % than ‘P’ due to the combined fabric structure with yarn floating and overlapping.
Figure 3 shows the clothing pressure and the size of knitted specimen; in addition, a reduced size led to a consistently higher course-wise clothing pressure. A similar trend was also found in correlation with clothing pressure and stretch of knitted specimen (Fig. 6). The observed clothing pressure value of knitted specimen having lower stretch ratio was also higher course-wise; however, there was no significant tendency between clothing pressure and stretch ratio in wale-wise.
The correlation with clothing pressure and elastic recovery ratio (Fig. 7a, b) indicated no distinct difference recovery ratio among knit structures compared to clothing pressure value. Further research with a higher stretch knitted fabric than used this study should be used to define the relationship between clothing pressure and the elastic recovery of high stretch knitted fabric.