The tensile strength is the measure of maximum force that fabric can bear or support, elongate before it breaks. For determining tensile strength ISO 13934-1 test methods mentioned the strip test. The specimen used in this test is usually a 2 inch wide piece of fabric prepared by initially cutting the material to a width of about 2.5 inch and removing threads from both edges until the width has been reduced to 2 inch. The test length should be 8 inch between the jaws and so enough extra length must be allowed for gripping in the jaws. Under optimum conditions, the specimen will be mounted centrally. Security gripped along the full width to prevent slipping. The load is applied uniformly across the full specimen width. If a test specimen breaks within 0.25 inch of the line of contact of either of pairs of jaws at a load substantial less than the average of normal breaks, the results shall be recorded [5].

Tearing resistance is one of the important properties of a textile fabric. The tear strength of a fabric indicates its resistance to tearing force. For Elmendorf tear resistance testing, at first we took specimen 100 mm × 75 mm. The template was placed on the specimen and cut according to the template. A slit was created at the middle point at the specimen which range was 20 mm. In the test the Elmendorf continuous to tear the fabric from the end of the slit to the opposite edge a distance of 43 mm. Pendulum lever mechanism was used here [6].

Rubbing fastness is the resistance to fading of dyed textiles when rubbed against a rough surface. This test determines the fastness of dyestuff to either wet or dry rubbing. For rubbing fastness testing (Figure 3) test specimen 15 cm × 5 cm was placed on the base of the crock meter. Square of white test cloth (5 cm × 5 cm) of cotton desized, bleached but without finish was attached to the finger of the crock meter. This finger was used in rubbing action on the sample specimen i.e. rubbing 10 cm long to and fro 10 times at 10 seconds. 20 rubs in 10 s and finger pressure on the specimen was 9 N. For testing dry and wet rubbing separate specimen was used. Three specimens for dry rubbing and three specimens for wet

rubbing for warp direction similarly three for dry and three for wet rubbing for weft direction for both fabric. Change in color in the specimen and staining in the white cloth was determined by grey scale [7].

The specification of the crock meter was Brand: James Heal; Origin: UK; Model: 670HD Crock Meter; Volts: N/A; Phase: N/A; Amps: N/A; Frequency: N/A; S/N: 670/15/1431.

For this test four specimens each 5 inch × 5 inch were cut from the fabric. A seam allowance of 12 mm was marked on the back of each square. In two of the samples the seam was marked parallel to the warp direction and in the other two parallel to the weft direction. The samples were then folded face to face and a seam was sewn on the marked line. This gave two specimens with the seam parallel to the warp and two with the seam parallel to the weft. Each specimen was turned inside out and 6 mm cut off each end of it thus removing any sewing distortion. The fabric tubes made were then mounted on rubber tubes so that the length of tube showing at each end was the same. Each of the loose ends was taped with poly (vinyl chloride) (PVC) tape so that 6 mm of the rubber tube was left exposed. All four specimens were then placed in one pilling box. The samples were then tumbled together in a cork-lined box as. The usual number of revolutions used in the test was 18,000 which take 5 hrs [8].

The specification of the machine was Brand: James Heal; Origin: UK; Model: 1516 ORBITOR; Volts: 110-230 V; Frequency: 50/60 Hz; Amp: 0.5 A; S/N: 1516/2/1014.

A specimen was cut from the fabrics with a template 2 inch long by 1 inch wide. It was carefully creased by folding in half placing it between two glass plates and adding a 2 kg weight.

After 1 min the weight was removed and the specimen transferred to the fabrics clamp on the instrument and allowed to recover from crease. As it recovers, the dial shown in Figure 4 of the instrument was rotated to keep the free

edge of the specimen in line with the knife edge. At the end of the time period allowed for recovery, usually 1 min the recovery angle in degrees was read on the engraved scale. Warp and weft way recovery were reported separately to the nearest degree from the mean values of ten tests in each direction [9].

Drape is the property of fabric which indicates the ability of a fabric to assume a graceful appearance in use. It is the opposite characteristically feature of stiffness of the fabric. In this testing process a circular specimen about 10 inch in diameter was supported on a circular disk (see Figure 5) about 5 inch diameter and the unsupported area drape over the edge. The fabric will assume some folded configuration and the shape of the project area will not be circular. The drape was then measured in terms of drape co-efficient F considering areas. Drape co-efficient is the ratio of projected area of the draped specimen to its undraped of the area of the supporting disk. Thus, F = (As – Ad)/(AD – Ad), where AD is the area of the specimen, Ad is the area of the supporting disk and As is the actual projected area of the specimen [10].

The specification of the machine is Model: Drape Tester; Brand: James Heal; Origin: UK.

Fastness to washing is one of the important dyeing properties to the customer. For testing washing fastness cut out a specimen of 10 cm × 4 cm and make sure all colors were included (if necessary use additional specimen) in it, sewing it along all four edges with the same size of multi-fibre fabric (Figure 6). This was the composite test specimen. The composite specimen was tested in a wash wheel or an equivalent apparatus at 95˚C ± 20˚C for 30 minutes using the ECE color fastness test detergent 77 (ISO std. Soap) 5 g/l and 2 g/l soda ash with 10 steel balls to give a liquor ratio of 50:1 [11].

The color intensities of 100% cotton 2/1 S twill and 3/1 S twill woven fabrics are

measured and compared by using a UV VIS-NIR reflective spectrometer (Spectra Flash SF 600 X, USA), over the range of 360 nm to 700 nm [12].

The results show that the warp-wise tensile strength (Table 1) of 2/1 twill woven fabric is more than the warp-wise tensile strength of 3/1 twill woven fabric. And also weft-wise tensile strength (Table 2) of 2/1 twill woven is more than the weft-wise tensile strength of 3/1 twill woven fabric. The tensile strength of a fabric varies with: 1) EPI variation; 2) PPI variation; 3) Count variation and also depends on the construction of the fabric.

Tear strength is the resistance of the fabric against tearing or force required to propagate the tear once it is initiated. After completing test the following results are found.

From Figure 7 it is seen that tearing Strength test for Twill 2/1 (warp Way) are 1.191 lbf and 1.256 lbf whereas 3/1 twill (Warp Way) are 1.388 lbf and 1.519 lbf∙2/1 twill has lower strength than 3/1 twill due to lose constructions and fewer interlacing, where the yarns can easily move and bunch together, 3/1 twill weave shows higher resistance to the applied force than 2/1 Twill weave.

A fastness is a place, such as a castle, which is considered safe because it is difficult to reach or easy to defend against attack. This test is designed to determine

the degree of color which may be transferred from the surface of a colored fabric to a specify test cloth for rubbing (which could be dry and wet).

After testing color fastness to rubbing we have found the following results:

Dry rubbing fastness results (Figure 8) of 3/1 twill and 2/1 twill in both warp direction and weft direction are same (Figure 8(a) and Figure 8(b)) and wet rubbing fastness (Figure 9) results of 2/1 twill and 3/1 twill in both warp and weft direction are slightly changed. From Figure 9(a) & Figure 9(b), it is found that wet rubbing for 3/1 twill in both warp and weft direction fair and moderate respectively. But it for 2/1 twill are good to moderate fair respectively.

Pilling is a fabric surface fault characterized by little pills of entangled fiber clinging to the cloth surface & giving the garments an unsightly appearance.

It is seen from Figure 10 that pill rating for both samples (2/1 twill & 3/1) are same. Their moderate pilling behavior due to less interlacement of the weaves the migratory tendency of the fibers is comparatively high. As a result, it is found that 2/1 twill fabric and 3/1 twill fabric is same resistance to pill formation.

Crease recovery is determined depending upon the recovery angle. If the angle is 0˚ then recovery is zero and if the angle is 180˚ then recovery is full.

Here the recovery angle (shown in Figure 11) for the 3/1 twill woven fabric in warp way is 105.2˚ and in weft way is 79.6˚ (from Table 3). The recovery angle

for 2/1 twill woven fabric in warp way is 84.9˚ and in weft way is 52.8˚ (from Table 4).

As warp yarn is characterized by various treatments such as sizing, so it achieved higher tensile strength than weft yarn. For this reason its recovery behavior is better than weft yarn.

The crease recovery of 3/1 and 2/1 twill fabrics in warp way is greater than the weft way. Because with the increase in the yarn linear density, yarn becomes coarser. For this reason the number of the fibers in the cross-section increases and correspondingly elasticity decrease and the crease recovery becomes harder.

The draping quality of fabric is affected by the stiffness of the Fabric. Here, Drape Co-efficiency of 3/1 twill is greater than 2/1 twill (see Table 5) because of the 3/1 twill less interlacement than 2/1 twill.

The results show (Figure 12) that color staining on Acetate, Cotton, Acrylic and Wool fiber for 2/1 twill is higher than 3/1 twill fabric (Figure 12). And Color staining on Polyester for 2/1 twill is lower than 3/1 twill fabric.

Color strength of samples (Figure 13) 2/1 Twill & 3/1 Twill woven fabrics are measured through K/S value. When reflectance is more, absorbance is more, indicates the more K/S value. K/S value was measured in 360 - 700 nm wave length. For 2/1 Twill woven fabric value of K/S is 3.616 at 360 nm and 0.483 at 700 nm. For 3/1 Twill woven fabric value of K/S is 3.635 at 360 nm and 0.492 at 700 nm wave length.