chapter 5 fabric stiffness and drape -...
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CHAPTER 5
FABRIC STIFFNESS AND DRAPE
5.1 INTRODUCTION
This chapter discusses the fabric stiffness and drape for commercial
fabrics by a simple method utilizing small strips of fabric samples.
5.2 MATERIALS AND METHODS
The materials have already been described in chapter 3. The
method used for measurement has been described in the above chapter. Figure
5.1 shows the instrument used for measuring drape angle.
Figure 5.1 Drape tester
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5.3 RESULTS AND DISCUSSION
That 5 cm strip length is sufficient for the measurement of
drape angles is evident from the Table 5.1. For the eleven samples included in
Group 2, the drape angles were measured and the values are given in Table.
The drape was normally measured by taking 30 cm of samples and these are
also given in the Table 5.1.
Table 5.1 Drape of fabrics
CFF Drape angle measured
by 5 cm strip length
Drape by 30 cm
sample (%)
2 32 52
1 55 43
0.5 65 32
0.969 62 35
1 51 48
0.5 65 30
1.188 31 52
1.5 55 46
1.25 52 42
1.5 55 38
1.25 60 37
It is evident that there is a good correlation between the two
methods i.e., 5 cm strip and 30 cm circular sample. The correlation between
CFF and drape angle is 0.718 and is highly significant. Values of drape angle
for 48 fabrics are given in Table 5.2.
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Table 5.2 Drape angle of fabrics
Drape angle Flexural rigidity (mg.cm) Fabric
No. Warp Weft Warp Weft
1 51 44 82 160
2 57 68 79 50
3 48 45 121 150
4 68 65 59 56
5 67 64 59 65
6 72 59 50 98
7 68 43 52 122
8 62 68 88 71
9 15 19 702 672
10 52 41 140 204
11 62 64 46 36
12 72 64 40 48
13 69 64 41 54
14 62 77 55 24
15 71 70 72 41
16 68 68 72 67
17 29 44 154 104
18 54 58 110 70
19 62 73 92 46
20 57 59 85 67
21 52 65 70 45
22 65 67 74 53
23 66 72 80 64
24 78 76 13 14
25 76 72 18 15
26 76 72 17 14
27 77 70 14 10
28 59 56 150 74
29 59 62 55 80
30 53 60 160 66
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Table 5.2 (Continued)
Drape angle Flexural rigidity (mg.cm) Fabric
No. Warp Weft Warp Weft
31 60 52 46 43
32 33 16 51 67
33 67 68 40 45
34 64 73 64 73
35 35 41 43 55
36 70 68 202 260
37 79 78 159 261
38 81 78 214 153
39 75 77 156 323
40 79 82 300 173
41 48 67 145 160
42 65 57 216 244
43 38 61 170 243
44 66 67 113 2633
45 67 67 106 158
46 72 68 115 72
47 57 58 589 539
48 71 67 133 118
It is clear that 5 cm strip length is sufficient to measure drape when
the drape angle is high. Flexural rigidity values are also given in Table 5.2.
Higher drape angle is associated with lower flexural rigidity.
5.4 CONCLUSION
The new tester is simple and requires only 5 cm strip. The drape
angle can measured from one measurement. An excellent correlation between
the drape measured by conventional method and 5 cm strip has been obtained.